576
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Kuzin II, Snyder JE, Ugine GD, Wu D, Lee S, Bushnell T, Insel RA, Young FM, Bottaro A. Tetracyclines inhibit activated B cell function. Int Immunol 2001; 13:921-31. [PMID: 11431422 DOI: 10.1093/intimm/13.7.921] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Tetracyclines have recently been shown to exert a number of pleiotropic anti-inflammatory and immunomodulatory activities, independent of their antibiotic properties. These include the ability to inhibit metalloproteinases (MP), a class of enzymes involved in crucial cellular functions such as the shedding of soluble mediators and their receptors from the cell surface, as well as interaction with, and remodeling of, the extracellular matrix. Here we report that doxycycline at therapeutic concentrations (1--5 microg/ml) significantly suppresses Ig secretion and class switching by in vitro activated murine B cells. Suppression of Ig secretion correlates with a decrease in levels of mRNA for the terminal B cell differentiation-associated genes Blimp-1 and mad-4, as well as to a reduction in expression of the plasma cell markers Syndecan-1 and J chain. Inhibition of class switching occurs at the recombination stage and is also induced by other MP inhibitors, including tetracycline analogs lacking antibiotic activity and the chemically unrelated hydroxamate KB8301. These novel, direct effects of MP inhibitors on B lymphocytes suggest an intrinsic role for MP in B cell activation and likely explain some of the observed in vivo immunomodulatory properties of tetracyclines. Moreover, these findings have significant implications for tetracycline therapy in Ig-mediated autoimmune or allergic diseases and raise questions about the use of doxycycline-inducible transgenic systems for the study of B cell function.
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577
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Wang X, Zuckerman B, Kaufman G, Wise P, Hill M, Niu T, Ryan L, Wu D, Xu X. Molecular epidemiology of preterm delivery: methodology and challenges. Paediatr Perinat Epidemiol 2001; 15 Suppl 2:63-77. [PMID: 11520401 DOI: 10.1046/j.1365-3016.2001.00009.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Preterm delivery (PTD) appears to be a complex trait determined by both genetic and environmental factors. Few studies have examined genetic influence on PTD. The overall goal of our study is to examine major candidate genes of PTD and to test gene-environment interactions. Our study includes 500 preterm trios, including 500 preterm babies and their parents and 500 maternal age-matched term controls. We will perform the transmission/disequilibrium test (TDT) on candidate genes thought to be important in each of the four biological pathways of PTD: (1) decidual chorioamionotic inflammation: interleukin 1 (IL-1), IL-6, and tumour necrosis factor (TNF); (2) maternal and fetal stress: corticotropin-releasing hormone (CRH); (3) uteroplacental vascular lesions: methylenetereahydrofolate reductase (MTHFR); and (4) susceptibility to environmental toxins: GSTM1, GSTT1, CYP1A1, CYP2D6, CYP2E1, NAT2, NQO1, ALDH2, and EPHX. We will also perform standard case-control analyses on the 500 preterm cases and 500 term controls to examine gene-environment interactions. The major environmental, nutritional and social factors as well as clinical variables known or suspected to be associated with PTD will be used to test for gene-environment interactions. This study integrates epidemiological and clinical data as well as genetic markers along major pathogenic pathways of PTD. The findings from this study should improve our understanding of genetic influences on PTD and gene-environment interactions.
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578
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Murdoch B, Gallacher L, Awaraji C, Hess DA, Keeney M, Jay K, Chadwick K, Fowley SR, Howson-Jan K, Chin Yee I, Wu D, Srour ED, Fellows F, Bhatia M. Circulating hematopoietic stem cells serve as novel targets for in utero gene therapy. FASEB J 2001; 15:1628-30. [PMID: 11427508 DOI: 10.1096/fj.00-0654fje] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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579
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Wang Z, Chen C, Niu T, Wu D, Yang J, Wang B, Fang Z, Yandava CN, Drazen JM, Weiss ST, Xu X. Association of asthma with beta(2)-adrenergic receptor gene polymorphism and cigarette smoking. Am J Respir Crit Care Med 2001; 163:1404-9. [PMID: 11371409 DOI: 10.1164/ajrccm.163.6.2001101] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Recent studies have suggested that two polymorphisms of the beta(2)-adrenergic receptor (beta(2)AR) gene at codons 16 (arginine to glycine) and 27 (glutamine to glutamate) affect an individual's airway responsiveness, or response to acute or chronic beta(2)-agonist therapy but are not risk factors for asthma. We hypothesize that there is an interaction effect on asthma between the beta(2)AR gene polymorphisms and cigarette smoking. A case-control study was conducted in 128 asthma cases and 136 control individuals identified from 10,014 studied subjects in rural Anqing, China. Allele-specific polymerase chain reaction (PCR) was used to genotype beta(2)AR gene polymorphisms. Multiple logistic regression was used to adjust for potential confounding factors. We found a marginally significant interaction between cigarette smoking and beta(2)AR-16 genotype after adjusting for important confounding factors (p = 0.06). Specifically, we found that compared with never-smoking Gly-16 homozygotes, those ever-smokers who are Arg-16 homozygotes had a significantly increased risk of asthma (odds ratio [OR] = 7.81; 95% confidence interval [CI]: 2.07 to 29.5). This association showed a clear dose-response relationship with the number of cigarettes smoked. However, there was no significant association of asthma with polymorphisms of the beta(2)AR at position 27 (OR = 1.38; 95% CI: 0.69 to 2.73). Our study suggests a gene-environment interaction between the Arg-16 genotype and ever cigarette smoking with respect to the susceptibility of an individual to asthma.
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580
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Vilalta A, Wu D, Margalith M, Hobart P. Rabbit EPO gene and cDNA: expression of rabbit EPO after intramuscular injection of pDNA. Biochem Biophys Res Commun 2001; 284:823-7. [PMID: 11396976 DOI: 10.1006/bbrc.2001.5028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Erythropoietin (EPO) cDNA was cloned from kidney total RNA of a NZW rabbit. The cDNA comprises a 588-bp open reading frame encoding a 195 amino acid protein with distinguishable regions of high of homology to other mammalian EPOs. Intramuscular injection of mice with a rabbit EPO expression plasmid resulted in a significant hematocrit increase. A rabbit genomic DNA fragment was also cloned using the rabbit EPO cDNA. This 4312-bp genomic DNA fragment contains sequences homologous to the mouse EPO promoter and hypoxia-responsive enhancer. In addition, the genomic DNA also presents a high degree of conservation to other regions involved in hypoxia response. Sequence divergence in the 3' UTR may indicate differences in regulation of mRNA stability or response to low oxygen tension.
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581
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Ling Z, Wu D, Zambre Y, Flamez D, Drucker DJ, Pipeleers DG, Schuit FC. Glucagon-like peptide 1 receptor signaling influences topography of islet cells in mice. Virchows Arch 2001; 438:382-7. [PMID: 11355173 DOI: 10.1007/s004280000374] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Glucagon-like peptide 1 (GLP-1) amplifies glucose-induced insulin release in vivo and in vitro. Activation of GLP-1 receptor (GLP-1R) signaling leads to differentiation of exocrine cells towards a beta-cell phenotype in vitro and stimulation of islet cell proliferation in vitro and in vivo, suggesting a potential role for GLP-1 in the modulation of islet growth and differentiation. To determine whether basal levels of GLP-1R signaling are essential for islet development, we examined islet cell composition and topography in GLP-1R-/- mice. Total beta-cell volume and number are not altered, but the topography of beta cells is markedly different in GLP-1R-/- mice compared with GLP-1R+/+ controls. The distribution of beta cells is shifted from large to small and medium-sized islets in the absence of GLP-1R signaling (large islets: 50 +/- 3% in GLP-1R+/+ vs 28 +/- 4% in GLP- 1R-/-, P < 0.01 and medium islets: 32 +/- 2% in GLP- 1R+/+ vs 48 +/- 3% in GLP-1R-/-, P < 0.001). Furthermore, GLP-1R-/- islets exhibit abnormalities in cell topography, with two to threefold more centrally located alpha cells detected in GLP-1R-/- islets. These alterations in alpha- and beta-cell topography indicate that basal levels of GLP-1 signaling in the normal rodent are involved in the normal cellular organization of the endocrine pancreas.
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582
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Yang M, Sang H, Rahman A, Wu D, Malik AB, Ye RD. Gα16Couples Chemoattractant Receptors to NF-κB Activation. THE JOURNAL OF IMMUNOLOGY 2001; 166:6885-92. [PMID: 11359849 DOI: 10.4049/jimmunol.166.11.6885] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The guanine nucleotide-binding regulatory protein alpha-subunit, Galpha(16), is primarily expressed in hemopoietic cells, and interacts with a large number of seven-membrane span receptors including chemoattractant receptors. We investigated the biological functions resulting from Galpha(16) coupling of chemoattractant receptors in a transfected cell model system. HeLa cells expressing a kappaB-driven luciferase reporter, Galpha(16), and the formyl peptide receptor responded to fMLP with a approximately 7- to 10-fold increase in luciferase activity. This response was accompanied by phosphorylation of IkappaBalpha and elevation of nuclear kappaB-DNA binding activity, indicating activation of NF-kappaB. In contrast to Galpha(16), expression of Galpha(q), Galpha(13), and Galpha(i2) resulted in a marginal increase in kappaB luciferase activity. A GTPase-deficient, constitutively active Galpha(16) mutant (Q212L) could replace agonist stimulation for activation of NF-kappaB. Furthermore, expression of Galpha(16) (Q212L) markedly enhanced TNF-alpha-induced kappaB reporter activity. The Galpha(16)-mediated NF-kappaB activation was paralleled by an increase in phospholipase C-beta activity, and was blocked by pharmacological inhibitors of protein kinase C (PKC) and by buffering of intracellular Ca(2+). The involvement of a conventional PKC isoform was confirmed by the finding that expression of PKCalpha enhanced the effect of Galpha(16), and a dominant negative PKCalpha partially blocked Galpha(16)-mediated NF-kappaB activation. In addition to formyl peptide receptor, Galpha(16) also enhanced NF-kappaB activation by the C5a and C3a receptors, and by CXC chemokine receptor 2 and CCR8. These results suggest a potential role of Galpha(16) in transcriptional regulation downstream of chemoattractant receptors.
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MESH Headings
- Active Transport, Cell Nucleus/genetics
- Amino Acid Substitution/genetics
- Cell Nucleus/genetics
- Cell Nucleus/metabolism
- Enzyme Activation/genetics
- GTP-Binding Protein alpha Subunits, Gq-G11
- Genes, Reporter
- Glutamine/genetics
- HeLa Cells
- Heterotrimeric GTP-Binding Proteins/biosynthesis
- Heterotrimeric GTP-Binding Proteins/genetics
- Heterotrimeric GTP-Binding Proteins/physiology
- Humans
- Isoenzymes/metabolism
- Isoenzymes/physiology
- Leucine/genetics
- Luciferases/genetics
- NF-kappa B/metabolism
- Phospholipase C beta
- Receptors, Chemokine/biosynthesis
- Receptors, Chemokine/genetics
- Receptors, Chemokine/metabolism
- Receptors, Formyl Peptide
- Receptors, Immunologic/biosynthesis
- Receptors, Immunologic/genetics
- Receptors, Peptide/biosynthesis
- Receptors, Peptide/genetics
- Signal Transduction/genetics
- Trans-Activators/genetics
- Trans-Activators/physiology
- Transfection/methods
- Type C Phospholipases/metabolism
- Type C Phospholipases/physiology
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583
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Yan F, Zhou K, Wu D, Yang J, Gong J, Shen J. [Evaluation of dynamic enhanced fast multiplanar spoiling gradient recalled(FMPSPGR) in the diagnosis of small hepatocellular carcinoma]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2001; 9:139-41. [PMID: 11412386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
OBJECTIVE To analyze the features of small hepotocellular carcinoma (SHCC) by spin echo (SE) sequence and dynamic enhanced FMPSPGR, and to compare the sensitivity for detecting and the accuracy for characterization, further to discuss the value of FMPSPGR in the diagnosis of SHCC. METHODS SE T(1)WI, T(2)WI and FMPSPGR dynamic imaging of the liver were performed for 58 patients with SHCC. The sensitivity for detecting and accuracy for characterization were statistically compared. RESULTS Seventy-two lesions were found in 58 patients. In the detection of SHCC, the order of the sensitivity was dynamic enhanced FMPSPGR>SE T(2)WI>no-enhanced FMPSPGR>SE T(1)WI. Dynamic enhanced FMPSPGR was significantly higher than any of the others. There was significant difference between no-enhanced FMPSPGR and SE T(2)WI, but not significant difference between T(2)WI and no-enhanced FMPSPGR. In the characterization of SHCC, the accuracy of pre- and post-contrast FMPSPGR was significantly higher than that of SE (T(1)WI+T(2)WI) with remarkable statistical difference. CONCLUSIONS FMPSPGR dynamic imaging is superior to SE in the detection and characterization of SHCC. The sensitivity for detecting and the accuracy for characterization will be improved when both FMPSPGR and SE are used.
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584
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Wu JH, Lee YT, Hsu HC, Hsieh LL, Wen MS, Chern MS, Wu D. Further characterization of apolipoprotein B genetic variations in Taiwanese. Hum Biol 2001; 73:451-60. [PMID: 11459425 DOI: 10.1353/hub.2001.0044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Apolipoprotein B (apoB, protein; APOB, gene) is the main protein component of low-density lipoprotein (LDL) and plays an important role in blood lipid metabolism. Previously, we have reported four APOB coding regions, 5' signal peptide, and 3' repeat sequence polymorphisms in our population. In this report, we further characterize other APOB genetic variations. The results illustrate that the mutation frequencies for Arg3500Gln (1/846 alleles), Arg4019Trp (2/786 alleles), -265 C/T promoter region (0/264 alleles), and intron 2 A/G (0/450 alleles) are very low. Our population showed a frequency of 68.9% for the B4311 Ser allele. The B4311 Asn allele was associated with a higher apoB level than the Ser group (p < 0.05) in normal controls. In the normal controls, a higher B4311 Asn/Asn genotype frequency was found in the group with total cholesterol (TC) > 200 mg/dL and apoB concentration > 85 mg/dL than in the group with a TC < 200 mg/dL and apoB < 85 mg/dL (p = 0.03 for TC comparison).
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585
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Wang H, Peng R, Wu D, Li S. [Serum glutathione S-transferase in bromobenzene-induced acute hepato-toxicity in mice]. WEI SHENG YAN JIU = JOURNAL OF HYGIENE RESEARCH 2001; 30:135-7. [PMID: 12525079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
The activity of serum glutathione S-transferase (GST) was tested in bromobenzene-induced acute hepatotoxicity in mice. The data showed that a lot of small local necrosis in liver biopsy was observed and serum GST activity was increased after 2 h of treatment with bromobenzene (150 mg/kg i.p.) in mice. Serum alanine transaminase (ALT) activity was also gradually enhanced after 8 hours of treatment. The most obvious changes were at 16 hours of bromobenzene treatment, and serum GST activity was firstly restored to normal level after 24 hours of treatment. There were good positive correlations between serum GST, ALT, as well as serum GST and the changes on liver biopsy. Evaluating analysis of the diagnosis test showed that the sensitivity, specificity and accuracy was 89%, 75% and 82% in serum GST test, and 39%, 92% and 64% in serum ALT test respectively. The ROC work curve also demonstrated that serum GST was more sensitive and specific than serum ALT.
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586
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Zhang B, Gao X, Wu D. [Developmental toxicity of Al(NO3)3 on rat embryos]. WEI SHENG YAN JIU = JOURNAL OF HYGIENE RESEARCH 2001; 30:139-41. [PMID: 12525081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
The developmental toxicity and its mechanism of Al(NO3)3 on embryos in SD rats were studied. On the 9.5th day of gestation, the embryos were incubated in a whole-embryo culture system with Al(NO3)3 at concentrations of Al3+ from 0.6 to 9.0 micrograms/ml in culture media for 48 hrs. Viable embryos were evaluated by Brown's morphological scoring system, and the diameter of yolk sac, crown-rump, head length and the dry weight of embryos were measured. There was a dose-dependent relations of decreasing embryo development with increasing concentrations of Al3+. Yolk sac diameter, head length, dry weight and heart, forelimb as well as neural tube scores decreased significantly at 1.2 micrograms/ml (P < 0.05). When embryos were exposed to Al3+ at > or = 3.0 micrograms/ml, the embryonic development and morphological differentiation were obviously inhibited(P < 0.05); meanwhile, the incidence of dysmorphogenesis significantly increased, including neural tube defects and dorsiflexion teratogenesis. The results suggested that aluminum might be a developmental toxicant and dysmorphogenesis agent.
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587
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Miyata M, Kim HT, Hashimoto K, Lee TK, Cho SY, Jiang H, Wu Y, Jun K, Wu D, Kano M, Shin HS. Deficient long-term synaptic depression in the rostral cerebellum correlated with impaired motor learning in phospholipase C beta4 mutant mice. Eur J Neurosci 2001; 13:1945-54. [PMID: 11403688 DOI: 10.1046/j.0953-816x.2001.01570.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Long-term depression (LTD) at parallel fibre-Purkinje cell synapse of the cerebellum is thought to be a cellular substrate for motor learning. LTD requires activation of metabotropic glutamate receptor subtype 1 (mGluR1) and its downstream signalling pathways, which invariably involves phospholipase Cbetas (PLCbetas). PLCbetas consist of four isoforms (PLCbeta1-4) among which PLCbeta4 is the major isoform in most Purkinje cells in the rostral cerebellum (lobule 1 to the rostral half of lobule 6). We studied mutant mice deficient in PLCbeta4, and found that LTD was deficient in the rostral but not in the caudal cerebellum of the mutant. Basic properties of parallel fibre-Purkinje cell synapses and voltage-gated Ca2+ channel currents appeared normal. The mGluR1-mediated Ca2+ release induced by repetitive parallel fibre stimulation was absent in the rostral cerebellum of the mutant, suggesting that their LTD lesion was due to the defect in the mGluR1-mediated signalling in Purkinje cells. Importantly, the eyeblink conditioning, a simple form of discrete motor learning, was severely impaired in PLCbeta4 mutant mice. Wild-type mice developed the conditioned eyeblink response, when pairs of the conditioned stimulus (tone) and the unconditioned stimulus (periorbital shock) were repeatedly applied. In contrast, PLCbeta4 mutant mice could not learn the association between the conditioned and unconditioned stimuli, although their behavioural responses to the tone or to the periorbital shock appeared normal. These results strongly suggest that PLCbeta4 is essential for LTD in the rostral cerebellum, which may be required for the acuisition of the conditioned eyeblink response.
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588
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Zhu K, Xu Y, Wu D, Xu X, Huang L. Allogeneic peripheral blood stem cell transplantation for leukemia. Chin Med J (Engl) 2001; 114:493-6. [PMID: 11780411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To observe engraftment kinetics, the incidence and severity of graft-versus-host disease (GVHD), and clinical outcome on 40 recipients undergoing allogeneic peripheral blood stem cell transplantation (allo-PBSCT). METHODS From June 1997 to May 1999, forty leukemia patients with a median age of 35 years underwent allo-PBSCT. PBSC were mobilized with G-CSF at a dose of 5 micrograms/kg s.c. every 12 hours for 5 days. A median of 7.7 (2.0-16.8) x 10(6) CD34+ cells/kg was infused into the recipients. Busulfan-cyclophosphamide (BU-CY) was used as the conditioning regimen. All patients received cyclosporine A and either methotrexate (n = 34) or methylprednisolone (n = 6) for GVHD prophylaxis. RESULTS Engraftment of neutrophils and platelets was achieved at a median of 13 days (9-28 days) and 12 days (7-60 days) respectively. Patients receiving > or = 4 x 10(6) CD34+ cells/kg or given G-CSF post transplant had significantly accelerated neutrophil and platelet engraftment. Acute GVHD occurred in 17 of 40 patients (42.5%), with grade II-IV acute GVHD in 10 patients (25%). Chronic GVHD developed in 21 (9 extensive, 12 limited) out of 30 evaluable patients (21/30, 70%) with a median follow up of 380 days (180-900 days). Transplant related mortality was 17.5% and the relapse rate was 10%. The probability of leukemia free survival at 3 years was 72.5%. CONCLUSION Allo-PBSCT can provide rapid hematopoietic reconstitution without an increased incidence of acute GVHD, but may be associated with a high risk of chronic GVHD.
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589
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Guan J, Bennet L, George S, Wu D, Waldvogel HJ, Gluckman PD, Faull RL, Crosier PS, Gunn AJ. Insulin-like growth factor-1 reduces postischemic white matter injury in fetal sheep. J Cereb Blood Flow Metab 2001; 21:493-502. [PMID: 11333359 DOI: 10.1097/00004647-200105000-00003] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Insulin-like growth factor-1 (IGF-1) is known to be important for oligodendrocyte survival and myelination. In the current study, the authors examined the hypothesis that exogenous IGF-1 could reduce postischemic white matter injury. Bilateral brain injury was induced in near-term fetal sheep by 30 minutes of reversible carotid artery occlusion. Ninety minutes after ischemia, either vehicle (n = 8) or a single dose of 3 microg IGF-1 (n = 9) was infused intracerebroventricularly over 1 hour. White matter changes were assessed after 4 days recovery in the parasagittal intragyral white matter and underlying corona radiata. Proteolipid protein (PLP) mRNA staining was used to identify bioactive oligodendrocytes. Glial fibrillary acidic protein (GFAP) and isolectin B-4 immunoreactivity were used to label astrocytes and microglia, respectively. Myelin basic protein (MBP) density and the area of the intragyral white matter tracts were determined by image analysis. Insulin-like growth factor-1 treatment was associated with significantly reduced loss of oligodendrocytes in the intragyral white matter (P < 0.05), with improved MBP density (P < 0.05), reduced tissue swelling, and increased numbers of GFAP and isolectin B-4 positive cells compared with vehicle treatment. After ischemia there was a close association of PLP mRNA labeled cells with reactive astrocytes and macrophages/microglia. In conclusion, IGF-1 can prevent delayed, postischemic oligodendrocyte cell loss and associated demyelination.
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590
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Lilja JF, Wu D, Reynolds RK, Lin J. Growth suppression activity of the PTEN tumor suppressor gene in human endometrial cancer cells. Anticancer Res 2001; 21:1969-74. [PMID: 11497285] [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
The AKT proteins are constitutively activated in several types of human cancers, which may play a role in carcinogenesis. In this study, we examined the activation of AKT in a panel of human endometrial cancer cell lines and tumor samples in this study. Two endometrial cancer cell lines, Ishikawa (ISK) and RL-95 and several tumor samples showed elevated levels of phosphorylated AKT PTEN, which is mutated in 45% of endometrial cancers, is a negative regulator of AKT. We examined the growth suppression activity of PTEN in ISK and KLE endometrial cancer cells. Expression of PTEN significantly suppressed the growth of both cell clines. In primary rat embryo fibroblasts, PTEN also inhibited malignant transformation mediated by ras and c-myc oncogenes. These two oncogenes are commonly mutated or amplified in endometrial cancer. These results suggest that PTEN may be a potent therapeutic agent for endometrial cancer.
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591
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Wu D, Luo S, Wang Y, Zhuang L, Chen Y, Peng C. Smads in human trophoblast cells: expression, regulation and role in TGF-beta-induced transcriptional activity. Mol Cell Endocrinol 2001; 175:111-21. [PMID: 11325521 DOI: 10.1016/s0303-7207(01)00397-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Smad proteins have recently been shown to be downstream signaling molecules that transduce TGF-beta signals from cell surface to the nucleus. To determine the mechanisms of TGF-beta action in human trophoblast cells, we investigated the expression and regulation of Smad2,3,4, and 7 mRNAs in a normal trophoblast cell line, NPC, and a cell line derived from choriocarcinoma, JEG-3. Messenger RNAs for Smad2,3,4 and 7 were detected in both NPC and JEG-3 cells. TGF-beta1 induced modest increases in Smad2 and Smad4 mRNA levels without affecting Smad3 mRNA expression in both cell lines. Significant increases in Smad7 mRNA levels in both NPC and JEG-3 cells following TGF-beta1 treatment were observed. TGF-beta1 also induced promoter activity of the Smad7 gene, indicating a direct effect at the level of gene transcription. The transcriptional activity of TGF-beta was examined in JEG-3 cells using two TGF-beta responsive reporter constructs, p3TP-Lux and pAR3-Lux. We found that Smad3 and to a lesser extent, Smad2 and Smad4, enhanced, while Smad7 inhibited, TGF-beta1-induced transcriptional activities. The basal and TGF-beta1-induced transcription can be blocked by overexpression of a dominant negative TGF-beta type II receptor. Taken together, these findings demonstrate that in human trophoblast cell lines, the Smad pathway involved in TGF-beta signal transduction is functional and that TGF-beta plays an autocrine role in regulating gene expression.
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592
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Wu D, Cederbaum AI. Removal of glutathione produces apoptosis and necrosis in HepG2 cells overexpressing CYP2E1. Alcohol Clin Exp Res 2001; 25:619-28. [PMID: 11329505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
BACKGROUND Previous studies have shown that addition of ethanol, iron, or arachidonic acid to HepG2 cells expressing CYP2E1 produced a loss in cell viability and caused apoptosis. These effects were enhanced when cellular reduced glutathione (GSH) levels were lowered by treatment with buthionine sulfoximine (BSO). Overexpression of CYP2E1 in HepG2 cells could produce toxicity even in the absence of added toxin after BSO treatment. Studies were carried out to characterize this CYP2E1-and BSO-dependent toxicity. METHODS HepG2 cells expressing CYP2E1 were treated with BSO for 1 to 4 days, and various parameters associated with apoptosis and cell viability were assayed. RESULTS Treatment of cells expressing CYP2E1 (E47 cells) with BSO resulted in apoptosis as well as necrosis. The apoptosis and necrosis were independent of each other. No toxicity was found with control HepG2 cells or HepG2 cells expressing CYP3A4 instead of CYP2E1 under these conditions. The antioxidant trolox partially prevented the apoptosis and necrosis, whereas diallylsulfide, a CYP2E1 inhibitor, was fully protective. The activity of caspase 3, but not caspases 1, 8, or 9, was increased in the BSO-treated E47 cells, and an inhibitor of caspase 3 prevented apoptosis. Damage to mitochondria appears to play a role in the CYP2E1- and BSO-dependent toxicity, because mitochondrial membrane potential was decreased and cyclosporin A, an inhibitor of the mitochondrial membrane permeability transition, prevented the apoptosis and the necrosis. The fall in membrane potential was prevented by trolox and diallylsulfide, suggesting damage to the mitochondria by CYP2E1-derived reactive oxygen species. CONCLUSIONS These results indicate the critical role of GSH in protecting against CYP2E1-mediated oxidative stress and that mitochondria may be a target for CYP2E1-derived reactive oxygen species, and suggest that interactions between CYP2E1, mitochondria, and altered GSH homeostasis may play a role in alcohol-induced liver injury.
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593
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Mao J, Wang J, Liu B, Pan W, Farr GH, Flynn C, Yuan H, Takada S, Kimelman D, Li L, Wu D. Low-density lipoprotein receptor-related protein-5 binds to Axin and regulates the canonical Wnt signaling pathway. Mol Cell 2001; 7:801-9. [PMID: 11336703 DOI: 10.1016/s1097-2765(01)00224-6] [Citation(s) in RCA: 630] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
To understand how the Wnt coreceptor LRP-5 is involved in transducing the canonical Wnt signals, we identified Axin as a protein that interacts with the intracellular domain of LRP-5. LRP-5, when expressed in fibroblast cells, showed no effect on the canonical Wnt signaling pathway by itself, but acted synergistically with Wnt. In contrast, LRP-5 mutants lacking the extracellular domain functioned as constitutively active forms that bind Axin and that induce LEF-1 activation by destabilizing Axin and stabilizing beta-catenin. Addition of Wnt caused the translocation of Axin to the membrane and enhanced the interaction between Axin and LRP-5. In addition, the LRP-5 sequences involved in interactions with Axin are required for LEF-1 activation. Thus, we conclude that the binding of Axin to LRP-5 is an important part of the Wnt signal transduction pathway.
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594
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Wu D, Cederbaum AI. Sodium salicylate increases CYP2E1 levels and enhances arachidonic acid toxicity in HepG2 cells and cultured rat hepatocytes. Mol Pharmacol 2001; 59:795-805. [PMID: 11259624 DOI: 10.1124/mol.59.4.795] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Sodium salicylate and acetylsalicylic acid are drugs used as anti-inflammatory agents. Salicylate prevents nuclear factor-kappa B activation and can cause apoptosis. However, salicylate, a substrate of CYP2E1, is also an antioxidant and can scavenge reactive oxygen species. Experiments were carried out to evaluate whether salicylate can modulate CYP2E1-dependent toxicity. Addition of a polyunsaturated fatty acid such as arachidonic acid (AA) to HepG2 cells resulted in loss of cell viability, especially in cells expressing CYP2E1 (E47 cells). Toxicity was enhanced by the addition of 1 to 10 mM salicylate to the E47 cells but not to control HepG2 cells or HepG2 cells expressing CYP3A4. Salicylate alone was not toxic, and the enhanced toxicity by AA in the presence of salicylate was prevented by diallyl sulfide, a CYP2E1 inhibitor, and by the antioxidant (+/-)6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid. Salicylate potentiated AA-induced lipid peroxidation in the E47 cells, a reaction blocked by diallyl sulfide. CYP2E1 levels were elevated by salicylate at concentrations (<5 mM), which did not increase CYP2E1 mRNA levels. This increase was associated with a decrease of CYP2E1 turnover by salicylate in the presence of cycloheximide. Salicylate also potentiated AA toxicity in hepatocytes isolated from pyrazole treated rats with high levels of CYP2E1 and from saline controls. In view of the potential role of CYP2E1 in contributing to alcohol-induced oxidative stress and liver injury, the potentiation of CYP2E1-dependent toxicity and the elevation of CYP2E1 levels by salicylate may be of clinical significance and merit caution in the use of salicylate and salicylate precursors such as acetylsalicylic acid with certain other drugs.
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595
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Wu D, Dai B, Pan W, Chen Z, Huang J, Tao J, Huang L, Mo C, Chen J, Zhao Y. [One stage otoplasty treatment for congenital malformations of the auricle and middle ear]. LIN CHUANG ER BI YAN HOU KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY 2001; 15:161-2. [PMID: 12541639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To investigate the application of one stage otoplasty for congenital atresia of the external acoustic canal and malformations of the middle ear and the auricle. METHOD Patients with the ear malformations were given surgical reconstruction of one stage otoplasty. The auricle was reconstructed with the rib which was encapsulated with the superthin temporal flap. According to the malformations of the middle ear in patients, I style tympanoplasty and III style tympanoplasty were carried out respectively. All patients were performed myringoplasty with temporal fascia and reconstructed the external acoustic canal with full thickness skin-grafting. RESULT A long term follow-up (4-6 years) demonstrated that 11 ears were survival of which 8 ears figuration were ideal. The hearing improvement was observed in all patients. CONCLUSION One stage otoplasty is effective for treatment of the congenital malformations of the external and middle ear.
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596
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Karanu FN, Murdoch B, Miyabayashi T, Ohno M, Koremoto M, Gallacher L, Wu D, Itoh A, Sakano S, Bhatia M. Human homologues of Delta-1 and Delta-4 function as mitogenic regulators of primitive human hematopoietic cells. Blood 2001; 97:1960-7. [PMID: 11264159 DOI: 10.1182/blood.v97.7.1960] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Delta-mediated Notch signaling controls cell fate decisions during invertebrate and murine development. However, in the human, functional roles for Delta have yet to be described. This study reports the characterization of Delta-1 and Delta-4 in the human. Human Delta-4 was found to be expressed in a wide range of adult and fetal tissues, including sites of hematopoiesis. Subsets of immature hematopoietic cells, along with stromal and endothelial cells that support hematopoiesis, were shown to express Notch and both Delta-1 and Delta-4. Soluble forms of human Delta-1 (h Delta-1) and h Delta-4 proteins were able to augment the proliferation of primitive human hematopoietic progenitors in vitro. Intravenous transplantation of treated cultures into immune-deficient mice revealed that h Delta-1 is capable of expanding pluripotent human hematopoietic repopulating cells detected in vivo. This study provides the first evidence for a role of Delta ligands as a mitogenic regulator of primitive hematopoietic cells in the human. (Blood. 2001;97:1960-1967)
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Adult
- Amino Acid Sequence
- Animals
- Blood Proteins/genetics
- Blood Proteins/physiology
- Calcium-Binding Proteins
- Cell Differentiation
- Cell Division/drug effects
- Cells, Cultured/drug effects
- Cells, Cultured/transplantation
- Fetal Blood/cytology
- Gene Expression Regulation, Developmental
- Graft Survival
- Growth Substances/genetics
- Growth Substances/physiology
- Hematopoietic Stem Cell Transplantation
- Hematopoietic Stem Cells/cytology
- Hematopoietic Stem Cells/drug effects
- Hematopoietic Stem Cells/metabolism
- Humans
- Infant, Newborn
- Intercellular Signaling Peptides and Proteins
- Intracellular Signaling Peptides and Proteins
- Membrane Proteins/biosynthesis
- Membrane Proteins/genetics
- Membrane Proteins/pharmacology
- Membrane Proteins/physiology
- Mice
- Mice, Inbred NOD
- Mice, SCID
- Mitosis/drug effects
- Mitosis/physiology
- Molecular Sequence Data
- Receptor, Notch1
- Receptor, Notch2
- Receptors, Cell Surface/biosynthesis
- Receptors, Cell Surface/genetics
- Recombinant Fusion Proteins/pharmacology
- Sequence Alignment
- Sequence Homology, Amino Acid
- Severe Combined Immunodeficiency/therapy
- Signal Transduction
- Solubility
- Transcription Factors
- Transplantation, Heterologous
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597
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Müller HG, Carey JR, Wu D, Liedo P, Vaupel JW. Reproductive potential predicts longevity of female Mediterranean fruitflies. Proc Biol Sci 2001; 268:445-50. [PMID: 11296855 PMCID: PMC1088626 DOI: 10.1098/rspb.2000.1370] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Reproduction exacts a price in terms of decreased survival. Our analysis of the interplay between age patterns of fecundity and mortality for individual female medflies (Ceratitis capitata) revealed that individual mortality is associated with the time-dynamics of the egg-laying trajectory. In a sample of 531 medflies, we found that each individual has a characteristic rate of decline in egg laying with age. This defines an individual's rate of reproductive exhaustion. This rate was shown to predict subsequent mortality The larger the remaining reproductive potential, the lower the subsequent mortality An increased mortality risk was seen in flies for which egg production declined rapidly early on, irrespective of the level of egg production. Thus, reproductive potential and lifetime are coupled in such a way that those flies which are able to profit most from an extended life span in terms of increased egg output are indeed likely to live longer.
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598
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Gu B, Wu D, Li M, Lü H. Potentiation of docetaxel antitumor activity by batimastat against mouse forestomach carcinoma. J Environ Pathol Toxicol Oncol 2001; 19:375-82. [PMID: 11213020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
Docetaxel is a chemical compound belonging to the taxoid class of anticancer agents. Batimastat (BB-94) is the first matrix metalloproteinase inhibitor entering clinical trials. To improve the treatment of tumors, we studied the combined effects of docetaxel and batimastat on mouse forestomach carcinoma (MFC), and compared them with doxorubicin. In vitro growth curve analysis, MTT assay, and clonogenic assay were used to determine the cytotoxic effect of docetaxel or/and BB-94 on MFC. They showed that docetaxel, but not BB-94, had a significant cytotoxicity and that the effect of docetaxel was not enhanced by BB-94. In an early stage MFC tumor model, an obvious antitumor effect of docetaxel or doxorubicin given iv at maximum tolerated dose (MTD) was observed. Tumor growth inhibition was greater for docetaxel + BB-94 (96.0%) than for doxorubicin + BB-94 (88.0%), docetaxel (89.0%), doxorubicin (68.0%), and BB-94 (33.0%). Docetaxel showed activity against advanced stage MFC tumor in a dose-dependent manner and was more effective at MTD than doxorubicin, with 4/5 regression, 46.5 days tumor growth delay, and 2.8 log10 tumor-cell kill. Our results suggest that docetaxel is an effective new cytotoxic drug against MFC tumor and that BB-94 enhances the antitumor activity of docetaxel in the dose and schedule used.
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599
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Guo YJ, Wu D, Chen RW, Sun SH. [Cloning, high level expression and purification of porcine IFN gamma]. SHENG WU GONG CHENG XUE BAO = CHINESE JOURNAL OF BIOTECHNOLOGY 2001; 17:183-6. [PMID: 11411228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Peripheral blood lymphocytes from a single swine were stimulated with Concavadin A for 17 h, and the total RNA was isolated from it. Then, the mRNA specific for porcine IFN gamma was amplified by reverse transcription polymerase chain reaction. After sequencing, the IFN gamma gene has been successfully inserted into vector pJLA-503 and highly expressed in E. coli. Recombinant porcine IFN gamma expressed as inclusion body, which was dissolved in 7 mol/L guanidine chloride and subsequently renatured by dilution in refolding buffer containing 0.5 mol/L L-arginine. In order to obtain pure protein, the renatured IFN gamma was purified by the chromatographies of SP-Sepharose FF and Sephacryl S-200 HR. As a result, the final pure product can been seen as a single band in SDS-PAGE, and the cytokine activity was verified by inhibiting the cytopathic effect.
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600
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Gu B, Wu D, Liang J. [Change of cone's motion perception in patients with primary open angle glaucoma]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 2001; 37:104-7. [PMID: 11864401] [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 assess the change of cone's motion perception in primary open angle glaucoma (POAG). METHODS Equi-luminance random dots moving test was used to determine the change of motion perception of blue, green and red cones in 51 eyes with POAG. To isolate the three kinds of cones, the blue, green and red visual targets were displayed on the yellow, purple and blue-green background respectively. RESULTS The direction discrimination thresholds of motion perception from blue, green and red cones were all damaged in POAG compared to that of the normal group, and among them the blue cone was the most obviously damaged. CONCLUSIONS These findings indicate that cone's motion perception, especially the blue cone's, may reveal pre-clinical visual nerve damage in POAG.
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