76
|
Tsao KC, Chan EC, Chang LY, Chang PY, Huang CG, Chen YP, Chang SC, Lin TY, Sun CF, Shih SR. Responses of IgM for enterovirus 71 infection. J Med Virol 2002; 68:574-80. [PMID: 12376966 DOI: 10.1002/jmv.10233] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A rapid serological assay was developed for detection of specific IgM to enterovirus 71, a human picornavirus that is usually associated with severe central nervous system complications. The sensitivity and specificity of this "in-house" mu-capture enzyme linked-immunosorbent assay was assessed by testing 213 serum samples. With the conventional virus culture as a standard method, the sensitivity and specificity were 91.5 and 93.1%, respectively, for this newly developed immunoassay. This method allows for detection of the IgM responses from the patients either infected by genotype B or genotype C of enterovirus 71. IgM can be detected as early as the second day from the onset of disease. IgM responses exhibit 100% positive rate from enterovirus 71-infected patients with complications, including encephalitis, meningitis, polio-like syndrome, pulmonary edema, and fatal cases. These findings suggest that detection of specific IgM by the use of enzyme linked-immunosorbent assay is a rapid and valuable way for the diagnosis of enterovirus 71 infection.
Collapse
|
77
|
McNamara MP, Bjornstad KA, Chang PY, Chou W, Lockett SJ, Blakely EA. Modulation of lens cell adhesion molecules by particle beams. Phys Med 2002; 17 Suppl 1:247-8. [PMID: 11776988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Cell adhesion molecules (CAMs) are proteins which anchor cells to each other and to the extracellular matrix (ECM), but whose functions also include signal transduction, differentiation, and apoptosis. We are testing a hypothesis that particle radiations modulate CAM expression and this contributes to radiation-induced lens opacification. We observed dose-dependent changes in the expression of beta 1-integrin and ICAM-1 in exponentially-growing and confluent cells of a differentiating human lens epithelial cell model after exposure to particle beams. Human lens epithelial (HLE) cells, less than 10 passages after their initial culture from fetal tissue, were grown on bovine corneal endothelial cell-derived ECM in medium containing 15% fetal bovine serum and supplemented with 5 ng/ml basic fibroblast growth factor (FGF-2). Multiple cell populations at three different stages of differentiation were prepared for experiment: cells in exponential growth, and cells at 5 and 10 days post-confluence. The differentiation status of cells was characterized morphologically by digital image analysis, and biochemically by Western blotting using lens epithelial and fiber cell-specific markers. Cultures were irradiated with single doses (4, 8 or 12 Gy) of 55 MeV protons and, along with unirradiated control samples, were fixed using -20 degrees C methanol at 6 hours after exposure. Replicate experiments and similar experiments with helium ions are in progress. The intracellular localization of beta 1-integrin and ICAM-1 was detected by immunofluorescence using monoclonal antibodies specific for each CAM. Cells known to express each CAM were also processed as positive controls. Both exponentially-growing and confluent, differentiating cells demonstrated a dramatic proton-dose-dependent modulation (upregulation for exponential cells, downregulation for confluent cells) and a change in the intracellular distribution of the beta 1-integrin, compared to unirradiated controls. In contrast, there was a dose-dependent increase in ICAM-1 immunofluorescence in confluent, but not exponentially-growing cells. These results suggest that proton irradiation downregulates beta 1-integrin and upregulates ICAM-1, potentially contributing to cell death or to aberrant differentiation via modulation of anchorage and/or signal transduction functions. Quantification of the expression levels of the CAMs by Western analysis is in progress.
Collapse
|
78
|
Chang PY, Kanazawa N, Lutze-Mann L, Winegar R. HZE particle radiation induces tissue-specific and p53-dependent mutagenesis in transgenic animals. Phys Med 2002; 17 Suppl 1:189-91. [PMID: 11776257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Transgenic animals, with the integrated target gene, provide a unique approach for measuring and characterizing mutations in any tissue of the animal. We are using the plasmid-based lacZ transgenic mice with different p53 genetic background to examine radiation-induced genetic damage resulting from exposure to heavy particle radiation. We measured lacZ mutation frequencies (MF) in the brain and spleen tissues at various times after exposing animals to an acute dose of 1 Gy of 1GeV/amu iron particles. MF in the spleen of p53+/+ animals increased up to 2.6-fold above spontaneous levels at 8 weeks post irradiation. In contrast, brain MF from the same animals increased 1.7-fold above controls in the same period. In the p53-/- animals, brain MF increased to 2.2-fold above spontaneous levels at 1 week after treatment, but returned to control levels thereafter. Radiation also induced alterations in the spectrum of mutants in both tissues, accompanied by changes in the frequency of mutants with deletions extending past the transgene into mouse genomic DNA. Our results indicate that the accumulation of transgene MF after radiation exposure is dependant on the tissue examined as well as the p53 genetic background of the animals.
Collapse
|
79
|
Wang CT, Grishanin R, Earles CA, Chang PY, Martin TF, Chapman ER, Jackson MB. Synaptotagmin modulation of fusion pore kinetics in regulated exocytosis of dense-core vesicles. Science 2001; 294:1111-5. [PMID: 11691996 DOI: 10.1126/science.1064002] [Citation(s) in RCA: 243] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
In the exocytosis of neurotransmitter, fusion pore opening represents the first instant of fluid contact between the vesicle lumen and extracellular space. The existence of the fusion pore has been established by electrical measurements, but its molecular composition is unknown. The possibility that synaptotagmin regulates fusion pores was investigated with amperometry to monitor exocytosis of single dense-core vesicles. Overexpression of synaptotagmin I prolonged the time from fusion pore opening to dilation, whereas synaptotagmin IV shortened this time. Both synaptotagmin isoforms reduced norepinephrine flux through open fusion pores. Thus, synaptotagmin interacts with fusion pores, possibly by associating with a core complex of membrane proteins and/or lipid.
Collapse
|
80
|
Chang PY, Chien YW, Huang FY, Chang NC, Perng DB. Computer-aided measurement and grading of cranial asymmetry in children with and without torticollis. CLINICAL ORTHODONTICS AND RESEARCH 2001; 4:200-5. [PMID: 11683809 DOI: 10.1034/j.1600-0544.2001.40404.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Our aim was to develop a simple, non-invasive method that could be used to objectively record cranial symmetry over time. We utilized this new method to investigate the relationship between torticollis and progressive plagiocephaly. From 1995 to 1999, the head shapes of 419 torticollis patients and 1 211 normal children were evaluated. We used Ezeform strip, a splint material, to make a permanent ring of the head circumference. Each head ring was recorded, scanned, and analyzed. An asymmetric index (AI) was designed. Double-blind comparisons of clinical assessment with AI values demonstrated a good agreement. Asymmetry of the cranium was found with similar frequency in torticollis and normal babies up to 12 months old. After 1 year of age, the deformity persists in patients with torticollis into their adolescence, while the normal group shows increased symmetry. This new recording system offers an objective and efficacious methods for following the natural history of cranial asymmetry.
Collapse
|
81
|
Chang PY, Luo S, Jiang T, Lee YT, Lu SC, Henry PD, Chen CH. Oxidized low-density lipoprotein downregulates endothelial basic fibroblast growth factor through a pertussis toxin-sensitive G-protein pathway: mediator role of platelet-activating factor-like phospholipids. Circulation 2001; 104:588-93. [PMID: 11479258 DOI: 10.1161/hc3101.092213] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Oxidized LDL (oxLDL) inhibits angiogenesis in part by downregulating endothelial basic fibroblast growth factor (bFGF). To determine the mechanism of the downregulation, we investigated the signal transduction pathway involving potential phospholipid mediators. METHODS AND RESULTS Cultured bovine aortic endothelial cells were incubated with PBS (lipoprotein-free control), LDL, or copper oxLDL under serum-free conditions. At 24 hours, oxLDL (50 microg/mL) decreased bFGF mRNA (Northern blot), bFGF protein (Western blot and ELISA), and concomitant DNA synthesis, all by 40% to 50% compared with PBS. LDL had no effect. Pretreating the cells with 100 ng/mL pertussis toxin (PTX) for 18 hours before oxLDL exposure almost completely blocked the inhibitory effects of oxLDL. In contrast, inhibiting other major cellular signal transduction pathways with PD-98059 (mitogen-activated protein kinase kinase inhibitor), HA-1004 (inhibitor of cGMP- and cAMP-dependent protein kinase), or Ro-31-8220 (protein kinase C inhibitor) or chelating intracellular Ca(2+) with BAPTA-AM failed to attenuate any of the oxLDL effects assayed. Addition to the cultures of WEB 2086, a specific antagonist of the PTX-sensitive G protein-coupled platelet-activating factor (PAF) receptor, blocked the action of oxLDL. Whereas PAF dispersed in the culture medium failed to produce oxLDL-like effects, degradation of PAF and PAF-like phospholipids accumulated in oxLDL with a recombinant human PAF acetylhydrolase eliminated the inhibitory effects of oxLDL on bFGF expression and DNA synthesis. CONCLUSIONS OxLDL suppresses endothelial bFGF expression and DNA synthesis through a PTX-sensitive heterotrimeric G-protein pathway involving mediator phospholipids similar, but not identical, to PAF.
Collapse
MESH Headings
- 1-Alkyl-2-acetylglycerophosphocholine Esterase
- Animals
- Azepines/pharmacology
- Blotting, Northern
- Blotting, Western
- Calcium-Calmodulin-Dependent Protein Kinases/antagonists & inhibitors
- Cattle
- Cells, Cultured
- Chelating Agents/pharmacology
- Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors
- Down-Regulation
- Egtazic Acid/analogs & derivatives
- Egtazic Acid/pharmacology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Enzyme Inhibitors/pharmacology
- Fibroblast Growth Factor 2/drug effects
- Fibroblast Growth Factor 2/genetics
- Fibroblast Growth Factor 2/metabolism
- Flavonoids/pharmacology
- GTP-Binding Proteins/metabolism
- Indoles/pharmacology
- Isoquinolines/pharmacology
- Lipoproteins, LDL/pharmacology
- Lipoproteins, LDL/physiology
- Pertussis Toxin
- Phospholipases A/pharmacology
- Platelet Activating Factor/physiology
- Protein Kinase C/antagonists & inhibitors
- RNA, Messenger/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Recombinant Proteins/pharmacology
- Signal Transduction
- Sulfonamides
- Triazoles/pharmacology
- Virulence Factors, Bordetella/pharmacology
Collapse
|
82
|
Manos EJ, Kim ML, Kassis J, Chang PY, Wells A, Jones DA. Dolichol-phosphate-mannose-3 (DPM3)/prostin-1 is a novel phospholipase C-gamma regulated gene negatively associated with prostate tumor invasion. Oncogene 2001; 20:2781-90. [PMID: 11420690 DOI: 10.1038/sj.onc.1204379] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2000] [Revised: 02/07/2001] [Accepted: 02/12/2001] [Indexed: 11/09/2022]
Abstract
The most ominous development in tumor progression is the transition to an invasive and metastatic phenotype. Little is known, however, about the molecular alterations that cause a tumor to become invasive. In view of this, we have used microarray expression analysis to evaluate the expression profiles of a unique panel of human DU145 prostate cancer sublines that vary in their invasive potential. The three DU145 sublines expressed epidermal growth factor (EGF) receptors that differed in their ability to activate phospholipase C-gamma (PLC gamma). Three-way analyses yielded 11 genes out of 4608 genes screened that associated directly or inversely with invasive potential. The gene whose expression correlated most strongly with lack of invasion was identified as a potential invasion suppressor and called prostin-1. Pharmacological inhibition of PLC gamma (U73122) confirmed that PLC gamma signaling suppressed prostin-1 in that U73122 treatment caused induction of prostin-1 in PLC gamma competent cells. The prostin-1 gene, conserved through phylogeny, is induced by androgen in LNCaP cells and encodes a 92 amino acid protein. The protein shares no extensive homologies with other known genes, yet was recently identified as a small stabilizer subunit of the dolichol-phosphate-mannose (DPM) synthase complex. That DPM3/prostin-1 might suppress tumor progression was supported by the finding that exogenous expression in COS cells leads to apoptosis. These findings support the use of model cell lines to identify putative tumor suppressors and promoters.
Collapse
|
83
|
Chang PY, Kanazawa N, Lutze-Mann L, Winegar RA. p53 deficiency alters the yield and spectrum of radiation-induced lacZ mutants in the brain of transgenic mice. Mutagenesis 2001; 16:7-15. [PMID: 11139594 DOI: 10.1093/mutage/16.1.7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Exposure to heavy particle radiation in the galacto-cosmic environment poses a significant risk in space exploration and the evaluation of radiation-induced genetic damage in tissues, especially in the central nervous system, is an important consideration in long-term manned space missions. We used a plasmid-based transgenic mouse model system, with the pUR288 lacZ transgene integrated in the genome of every cell of C57Bl/6(lacZ) mice, to evaluate the genetic damage induced by iron particle radiation. In order to examine the importance of genetic background on the radiation sensitivity of individuals, we cross-bred p53 wild-type lacZ transgenic mice with p53 nullizygous mice, producing lacZ transgenic mice that were either hemizygous or nullizygous for the p53 tumor suppressor gene. Animals were exposed to an acute dose of 1 Gy of iron particles and the lacZ mutation frequency (MF) in the brain was measured at time intervals from 1 to 16 weeks post-irradiation. Our results suggest that iron particles induced an increase in lacZ MF (2.4-fold increase in p53+/+ mice, 1.3-fold increase in p53+/- mice and 2.1-fold increase in p53-/- mice) and that this induction is both temporally regulated and p53 genotype dependent. Characterization of mutants based on their restriction patterns showed that the majority of the mutants arising spontaneously are derived from point mutations or small deletions in all three genotypes. Radiation induced alterations in the spectrum of deletion mutants and reorganization of the genome, as evidenced by the selection of mutants containing mouse genomic DNA. These observations are unique in that mutations in brain tissue after particle radiation exposure have never before been reported owing to technical limitations in most other mutation assays.
Collapse
|
84
|
Chang PY, Bjornstad K A, Chang E, McNamara M, Barcellos-Hoff MH, Lin SP, Aragon G, Polansky JR, Lui GM, Blakely EA. Particle irradiation induces FGF2 expression in normal human lens cells. Radiat Res 2000; 154:477-84. [PMID: 11025644 DOI: 10.1667/0033-7587(2000)154[0477:piifei]2.0.co;2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Particle Irradiation Induces FGF2 Expression in Normal Human Lens Cells. Particle radiations, including both proton and helium-ion beams, have been used to successfully treat choroidal melanoma, but with the complication of radiation-induced cataract. We have investigated a role for radiation-induced changes in the expression of basic fibroblast growth factor (FGF2) gene expression as part of the mechanism(s) underlying lens cell injury associated with cataract. Normal human lens epithelial (HLE) cells were cultured in vitro on extracellular matrix (ECM) originated from bovine corneal endothelial cells. This study reports evidence for rapid but transient induction of FGF2 transcripts, an increase of between 5- and 8-fold, within 0.5 h after exposure to particle radiation, followed by another wave of increased transcription at 2-3 h postirradiation. Immunofluorescence results confirm the enhanced levels of FGF2 protein rapidly after exposure to protons or helium ions, followed by another wave of increased activity unique to helium at 6 h postirradiation. This second wave of increased immunoreactivity was not observed in the proton-irradiated samples. Total FGF2 protein analysis after helium-ion exposures shows induced expression of three FGF2 isoforms, with an increase of up to 2-fold in the 18-kDa low-molecular-weight species. Studies of the effects of protons on individual FGF2 protein isoforms are in progress. Several mechanisms involving a role for FGF2 in radiation-induced cataract are discussed.
Collapse
|
85
|
Blakely EA, Bjornstad KA, Chang PY, McNamara MP, Chang E, Aragon G, Lin SP, Lui G, Polansky JR. Growth and differentiation of human lens epithelial cells in vitro on matrix. Invest Ophthalmol Vis Sci 2000; 41:3898-907. [PMID: 11053292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
PURPOSE To characterize the growth and maturation of nonimmortalized human lens epithelial (HLE) cells grown in vitro. METHODS HLE cells, established from 18-week prenatal lenses, were maintained on bovine corneal endothelial (BCE) extracellular matrix (ECM) in medium supplemented with basic fibroblast growth factor (FGF-2). The identity, growth, and differentiation of the cultures were characterized by karyotyping, cell morphology, and growth kinetics studies, reverse transcription-polymerase chain reaction (RT-PCR), immunofluorescence, and Western blot analysis. RESULTS HLE cells had a male, human diploid (2N = 46) karyotype. The population-doubling time of exponentially growing cells was 24 hours. After 15 days in culture, cell morphology changed, and lentoid formation was evident. Reverse transcription-polymerase chain reaction (RT-PCR) indicated expression of alphaA- and betaB2-crystallin, fibroblast growth factor receptor 1 (FGFR1), and major intrinsic protein (MIP26) in exponential growth. Western analyses of protein extracts show positive expression of three immunologically distinct classes of crystallin proteins (alphaA-, alphaB-, and betaB2-crystallin) with time in culture. By Western blot analysis, expression of p57(KIP2), a known marker of terminally differentiated fiber cells, was detectable in exponential cultures, and levels increased after confluence. MIP26 and gamma-crystallin protein expression was detected in confluent cultures, by using immunofluorescence, but not in exponentially growing cells. CONCLUSIONS HLE cells can be maintained for up to 4 months on ECM derived from BCE cells in medium containing FGF-2. With time in culture, the cells demonstrate morphologic characteristics of, and express protein markers for, lens fiber cell differentiation. This in vitro model will be useful for investigations of radiation-induced cataractogenesis and other studies of lens toxicity.
Collapse
MESH Headings
- Animals
- Aquaporins
- Blotting, Western
- Cattle
- Cell Differentiation
- Cells, Cultured
- Crystallins/genetics
- Crystallins/metabolism
- Cyclin-Dependent Kinase Inhibitor p57
- Endothelium, Corneal/cytology
- Epithelial Cells/cytology
- Epithelial Cells/metabolism
- Extracellular Matrix
- Eye Proteins/genetics
- Eye Proteins/metabolism
- Fibroblast Growth Factor 2/pharmacology
- Fluorescent Antibody Technique, Indirect
- Humans
- Karyotyping
- Lens, Crystalline/cytology
- Lens, Crystalline/metabolism
- Membrane Glycoproteins
- Microscopy, Fluorescence
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- RNA, Messenger/biosynthesis
- Receptor Protein-Tyrosine Kinases/genetics
- Receptor Protein-Tyrosine Kinases/metabolism
- Receptor, Fibroblast Growth Factor, Type 1
- Receptors, Fibroblast Growth Factor/genetics
- Receptors, Fibroblast Growth Factor/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
Collapse
|
86
|
Shi Y, Kanaani J, Menard-Rose V, Ma YH, Chang PY, Hanahan D, Tobin A, Grodsky G, Baekkeskov S. Increased expression of GAD65 and GABA in pancreatic beta-cells impairs first-phase insulin secretion. Am J Physiol Endocrinol Metab 2000; 279:E684-94. [PMID: 10950838 DOI: 10.1152/ajpendo.2000.279.3.e684] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The functional role of glutamate decarboxylase (GAD) and its product GABA in pancreatic islets has remained elusive. Mouse beta-cells express the larger isoform GAD67, whereas human islets express only the smaller isoform GAD65. We have generated two lines of transgenic mice expressing human GAD65 in pancreatic beta-cells (RIP7-hGAD65, Lines 1 and 2) to study the effect that GABA generated by this isoform has on islet cell function. The ascending order of hGAD65 expression and/or activity in beta-cells was Line 1 heterozygotes < Line 2 heterozygotes < Line 1 homozygotes. Line 1 heterozygotes have normal glucose tolerance, whereas Line 1 homozygotes and Line 2 heterozygotes exhibit impaired glucose tolerance and inhibition of insulin secretion in vivo in response to glucose. In addition, fasting levels of blood glucose are elevated and insulin is decreased in Line 1 homozygotes. Pancreas perfusion experiments suggest that GABA generated by GAD65 may function as a negative regulator of first-phase insulin secretion in response to glucose by affecting a step proximal to or at the K(ATP)(+) channel.
Collapse
|
87
|
Fang SB, Lee HC, Chang PY, Wang NL. Colonic perforation in two children with Campylobacter enterocolitis. Eur J Pediatr 2000; 159:714-5. [PMID: 11014478 DOI: 10.1007/s004310000508] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
88
|
Cherng JM, Lin CM, Lin CL, Huang SM, Chang HL, Lee CC, Chiang LC, Chang PY. Effects of VEGF121 and/or VEGF165 gene transfection on collateral circulation development. J Formos Med Assoc 2000; 99:603-11. [PMID: 10969502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
BACKGROUND AND PURPOSE Angiogenesis is regulated by various factors, including vascular endothelial growth factor (VEGF). Five isoforms of VEGF have been discovered: VEGF121, VEGF145, VEGF165, VEGF189, and VEGF206. The teleologic basis for the various VEGF isoforms remains unclear, but different VEGF isoforms may mediate distinct endothelial cell functions such as angiogenesis, vascular permeability, and differentiation. We sought to determine the effects of various VEGF isoforms on angiogenesis under ischemic conditions in rabbits. METHODS The effects of VEGF121 and/or VEGF165 gene transfection on collateral circulation development in ischemic rabbit hindlimb muscles were investigated by using naked plasmids encoding VEGF121 or VEGF165 (pVEGF121 or pVEGF165), either individually or in combination. pCMV beta was used as the control plasmid. The femoral artery on one side of New Zealand White rabbits was ligated. Ten days later, the ischemic muscles received direct intramuscular injection of pVEGF121 (500 micrograms), pVEGF165 (500 micrograms), or pVEGF121 (250 micrograms) + pVEGF165 (250 micrograms) in experimental groups, while pCMV beta (500 micrograms) was used in the control group. Therapeutic effects were evaluated 30 days later by anatomic and physiologic analysis. RESULTS Internal iliac angiography showed strong development of collateral circulation in all of the pVEGF-treated groups. In contrast, collateral arteries developed weakly in the control group. Combination treatment with both pVEGF121 and pVEGF165 did not result in additional improvement compared with pVEGF121 or pVEGF165 treatment alone (angiographic scores: pVEGF121 = 0.85 +/- 0.10; pVEGF165 = 0.81 +/- 0.11; pVEGF121 + pVEGF165 = 0.83 +/- 0.09; control = 0.53 +/- 0.09; p < 0.01). A favorable response in the development of circulation at the capillary level with pVEGF121 and/or pVEGF165 versus pCMV beta was also found. Blood pressure measurement and regional blood flow measurement using colored microspheres revealed similar results. CONCLUSIONS Our results show that direct intramuscular injection of naked DNA encoding VEGF121 or VEGF165, individually or in combination, is an effective method for gene transfer in an animal model of ischemic limbs and results in augmented collateral vascular development and tissue perfusion.
Collapse
|
89
|
Shih SR, Ho MS, Lin KH, Wu SL, Chen YT, Wu CN, Lin TY, Chang LY, Tsao KC, Ning HC, Chang PY, Jung SM, Hsueh C, Chang KS. Genetic analysis of enterovirus 71 isolated from fatal and non-fatal cases of hand, foot and mouth disease during an epidemic in Taiwan, 1998. Virus Res 2000; 68:127-36. [PMID: 10958984 DOI: 10.1016/s0168-1702(00)00162-3] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A large scale outbreak of hand-foot-and-mouth disease (HFMD) occurred in Taiwan in 1998, in which more than 80 children died of shock syndrome with pulmonary edema/hemorrhage. Enterovirus 71 was implicated as the cause of this outbreak. In order to understand the virological basis responsible for mortality on this scale, nucleotide sequences of VP1 that is important for serotypic specificity, and the 5'-non-coding region (5'-NCR) that is important for replication efficiency, were analyzed comparatively. Phylogenetic analysis of both VP1 and 5'-NCR of nine EV71 isolates derived from specimens of fatal patients and seven isolates derived from uncomplicated HFMD patients showed that all but one isolate fell into genotype B. The one distinct isolate from a case of uncomplicated HFMD belonged to genotype C that was clustered along with one isolate from Taiwan in 1986. Complete sequence analysis of two selected isolates, one from the spinal cord of a fatal case and one from the vesicle fluid of a patient with mild HFMD, confirmed a high degree (97-100%) of identity in nucleotide sequence throughout the entire genome, except focal regions of 3C and 3'-NCR where the nucleotide homology was 90-91%. The identity of the deduced amino acid sequence in the 3C region that encodes viral proteinase dropped further to 86%, a result of missense mutations at the first nucleotide position of many codons.
Collapse
|
90
|
Chang PY, Torous D, Lutze-Mann L, Winegar R. Impact of p53 status on heavy-ion radiation-induced micronuclei in circulating erythrocytes. Mutat Res 2000; 466:87-96. [PMID: 10751730 DOI: 10.1016/s1383-5718(00)00007-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Transgenic mice that differed in their p53 genetic status were exposed to an acute dose of highly charged and energetic (HZE) iron particle radiation. Micronuclei (MN) in two distinct populations of circulating peripheral blood erythrocytes, the immature reticulocytes (RETs) and the mature normochromatic erythrocytes (NCEs), were measured using a simple and efficient flow cytometric procedure. Our results show significant elevation in the frequency of micronucleated RETs (%MN-RETs) at 2 and 3 days post-radiation. At 3 days post-irradiation, the magnitude of the radiation-induced MN-RET was 2.3-fold higher in the irradiated p53 wild-type animals compared to the unirradiated controls, 2.5-fold higher in the p53 hemizygotes and 4.3-fold higher in the p53 nullizygotes. The persistence of this radiation-induced elevation of MN-RETs is dependent on the p53 genetic background of the animal. In the p53 wild-type and p53 hemizygotes, %MN-RETs returned to control levels by 9 days post-radiation. However, elevated levels of %MN-RETs in p53 nullizygous mice persisted beyond 56 days post-radiation. We also observed elevated MN-NCEs in the peripheral circulation after radiation, but the changes in radiation-induced levels of MN-NCEs appear dampened compared to those of the MN-RETs for all three strains of animals. These results suggest that the lack of p53 gene function may play a role in the iron particle radiation-induced genomic instability in stem cell populations in the hematopoietic system.
Collapse
|
91
|
Lee HC, Yeung CY, Chang PY, Sheu JC, Wang NL. Dilatation of the biliary tree in children: sonographic diagnosis and its clinical significance. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2000; 19:177-184. [PMID: 10709833 DOI: 10.7863/jum.2000.19.3.177] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We evaluated sonographically 162 children who met the criteria for biliary tract dilatation in the past 18 years. Of these, 131 patients were diagnosed as having anomalous dilatations of the biliary tree (including 112 with choledochal cysts and 19 with biliary duct dilatation and biliary atresia). Biliary tract dilatations in the other 31 patients were due to secondary causes or normal variants. All cases of intrahepatic biliary tree dilatation and those with both intra- and extrabiliary duct dilatations were anomalous. In 117 cases of extrahepatic biliary tract dilatation only, the mean diameter was widest in cases of choledochal cyst (21.4 +/- 12.1 mm, compared with cases of biliary tract dilatation with biliary atresia (10 +/- 2.4 mm), secondary biliary duct dilatation (8.5 +/- 1.5 mm), and normal variants (4.4 +/- 1.2 mm) (P < 0.001). Of the 43 infants with biliary tree dilatation, 24 (56%) had choledochal cysts and 19 (44%) had biliary tract dilatation associated with biliary atresia. Excluding cases associated with biliary atresia, the accuracy of diagnosing choledochal cysts in extrahepatic biliary tract dilatation was 71% and 97% using cutoffs of 7 mm and 10 mm as the minimum diameter, respectively.
Collapse
|
92
|
Wu TN, Shen CY, Lai JS, Goo CF, Ko KN, Chi HY, Chang PY, Liou SH. Effects of lead and noise exposures on hearing ability. ARCHIVES OF ENVIRONMENTAL HEALTH 2000; 55:109-14. [PMID: 10821511 DOI: 10.1080/00039890009603396] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Lead and noise, via different mechanisms, may damage hearing ability, and, in some cases, cause severe and irreversible damage. To explore possible independent and synergistic effects of lead and noise on auditory function, the authors conducted a cross-sectional study in two lead-battery manufacturing factories. Lead and noise were the two most common sources of occupational exposures in the factories. Blood lead level, ambient lead concentration, noise exposure level, and hearing thresholds of 339 lead-battery workers-including clerical and managerial staffs-were measured. The authors obtained demographics and working histories via an interview-based structured questionnaire. A total of 220 lead-battery workers were exposed to high levels of lead and noise; their average blood lead concentration was 56.9 microg/dl, and their average noise exposure level was 86.0 dBALeq. Multivariate analysis, in which possible risk factors of hearing ability were considered, demonstrated a significant correlation between a high, long-term lead exposure index (defined by duration of employment and ambient lead concentration) and decreased hearing ability. In contrast, such a correlation between short-term lead exposure (defined by blood lead level) and hearing ability was not significant. Furthermore, neither noise exposure level alone nor the interaction between noise exposure level and short- or long-term lead exposure was correlated significantly with hearing ability. The present study raises an important, but typically ignored, issue: lead exposure might precipitate a more severe auditory than noise-exposure effect. The preservation of workers' hearing ability requires that preventive measures be taken against noise exposure, which is as essential as measures taken against lead exposure.
Collapse
|
93
|
Wang JS, Lee HC, Sheu JC, Chang PY, Liang DC, Chen BF. Pancreatic tumors in children: report of three cases. ACTA PAEDIATRICA TAIWANICA = TAIWAN ER KE YI XUE HUI ZA ZHI 1999; 40:335-8. [PMID: 10910544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
From 1981 to 1996, we experienced 3 cases of pancreatic tumors in children--two pancreatoblastomas (PB) and one solid and cystic tumor (SCT). The ages were 1 month, 4 years, and 13 years of age respectively. The two cases of pancreatoblastoma initially presented as chronic diarrhea with failure to thrive, the other case presented with abdominal mass. All of them were studied by laboratory examination, ultrasonography, computed tomography and pathology. Increasing alpha- fetoprotein (AFP) levels were found in the 2 pancreatoblastoma cases, however, the level in the SCT case was normal. Abdominal sonography showed pancreatic masses with or without calcification, and the echogenicity may be solid and/or cystic. All patients underwent total excision of the tumors. We have reviewed the literature and find no pancreatoblastoma with chronic diarrhea was reported in young children, especially in neonate. Therefore, we suggest that young children presenting with an abdominal mass and/or weight loss should undergo imaging studies for the possibility of pancreatic tumors.
Collapse
|
94
|
Lin YH, Lee SC, Chang PY, Rajan PK, Sue SC, Wu WG. Heparin binding to cobra basic phospholipase A2 depends on heparin chain length and amino acid specificity. FEBS Lett 1999; 453:395-9. [PMID: 10405184 DOI: 10.1016/s0014-5793(99)00760-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Heparin is shown to bind specifically to the carboxy-terminal region of toxic type I phospholipase A2 from Naja nigricollis (N-PLA2) by competition assay using synthetic polypeptides and heparin affinity chromatography. The binding strength is seen to depend on heparin chain length and the presence of N-sulfate groups of heparin. It is observed that both electrostatic and non-electrostatic interactions are involved in the specific binding of heparin to the carboxy-terminus. When heparin's size is at least a decasaccharide, about two molecules of N-PLA2 bind to one molecule of heparin, as evidenced by the chemical estimate of protein to carbohydrate ratio in such N-PLA2/heparin complexes. Based on such a stoichiometric measurement and computer modeling of the N-PLA2/heparin complex, it is suggested that the binding sites of the two N-PLA2 molecules on one heparin molecule lie on the opposite sides of the heparin chain.
Collapse
|
95
|
Chu NF, Liou SH, Wu TN, Chang PY. Reappraisal of the relation between blood lead concentration and blood pressure among the general population in Taiwan. Occup Environ Med 1999; 56:30-3. [PMID: 10341743 PMCID: PMC1757651 DOI: 10.1136/oem.56.1.30] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES The relation between blood lead concentration (PbB) and blood pressure was examined in a Taiwan nationwide population survey of PbB from July 1993 to June 1994. METHODS After multistage sampling procedures, 2800 subjects (1471 males and 1329 females) with a mean (range) age of 44 (15-85) years were enrolled in this study. Anthropometric, blood pressure, and lifestyle factors were measured during household visits. The PbB was measured with a flameless atomic absorption spectrophotometer and all specimens were analysed in triplicate. RESULTS The mean (range) PbB among all study subjects was 6.5 (0.1-69.1) micrograms/dl; among males it was 7.3 (0.1-69.1) micrograms/dl and among females 5.7 (0.1-40.1) micrograms/dl). The mean (range) systolic blood pressure among all subjects was 123 (80-210) mm Hg, among males it was 127 (80-200) mm Hg and among females 119 (80-210) mm Hg. The diastolic blood pressure among all subjects was 78 (40-150) mm Hg; among males it was 80 (40-130) mm Hg; and among females 75 (40-150) mm Hg. Age, body height, body weight, and body mass index (BMI) were significantly correlated with systolic blood pressure or diastolic blood pressure in both sexes. The PbB (or the natural logarithmic transformed PbB) was not significantly correlated with blood pressure among males or females. After adjustment for the potential confounders of age, age2, BMI, milk intake, alcohol consumption, and cigarette smoking, systolic blood pressure was significantly associated with PbB among males with a regression coefficient (beta) of 0.185 (p = 0.015). No significant association between PbB and blood pressure was found among females. CONCLUSIONS From this study, only a weak association between systolic blood pressure and PbB was found among males. There was no strong evidence that PbB was a good predictor of blood pressure. However, the possibility that long term high body lead burden could cause high blood pressure could not be ruled out on the basis of this survey.
Collapse
|
96
|
Chen KT, Chen CJ, Chang PY, Morse DL. A nosocomial outbreak of malaria associated with contaminated catheters and contrast medium of a computed tomographic scanner. Infect Control Hosp Epidemiol 1999; 20:22-5. [PMID: 9927261 DOI: 10.1086/501557] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To identify the risk factors associated with an unexpected outbreak of malaria that occurred among seven patients in a general teaching hospital in Taipei in October 1995. DESIGN A three-stage case-control study was conducted to identify risk factors. PATIENTS We identified all 7 patients who were diagnosed as malaria cases and 69 controls from those undergoing computed tomography (CT) examination. METHODS Malaria was diagnosed by demonstrating the presence of Plasmodium falciparum on either thick or thin blood smears. Clinical characteristics and exposure information were collected from medical records and patient interviews. RESULTS The index case was infected by malaria when he visited Nigeria in early September and was diagnosed when he was hospitalized in hospital A in October. Among 10 patients examined with the Imatron scanner after the index case, all 6 who were injected with contrast medium were infected, but none of 4 examined without contrast medium were infected (P=.005). CONCLUSIONS This nosocomial outbreak of malaria was most likely due to transmission via a contaminated catheter and contrast medium used for CT scanning. Use of disposable catheters may avoid such nosocomial outbreaks in the future.
Collapse
|
97
|
Chu NF, Liou SH, Wu TN, Ko KN, Chang PY. Risk factors for high blood lead levels among the general population in Taiwan. Eur J Epidemiol 1998; 14:775-81. [PMID: 9928872 DOI: 10.1023/a:1007544205378] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE Environmental and occupational lead pollution is a common problem in both developing and industrialized countries. The purpose of this study is to evaluate the risk factors for high blood lead levels among the general population in Taiwan. METHODS After multi-stage sampling, we randomly selected 2803 subjects (1471 males and 1332 females) for this study. Univariate and multivariate logistic regression analyses were conducted to evaluate the risk of high blood lead. To control for differences in age and gender, all analyses were with age-adjusted and gender-stratified. RESULTS Among males, the mean age is 46 years (15 to 85 years), mean and median blood lead levels is 7.3 and 6.3 microg/dl, respectively. Among females, the mean age is 43 years (15 to 84 years), mean and median blood lead level is 5.7 and 4.8 microg/dl, respectively. Among males, the history of herbal drug use, drinking water from well or spring sources, and occupational lead exposure are significantly different between relatively high and normal blood lead level subjects. The history of occupational lead exposure, history of herbal drug use, and well or spring sources of drinking water are the major risk factors for high blood lead with odds ratio of 4.62 (95% CI: 2.82-7.55), 3.09 (95% CI: 1.60-5.97), 2.06 (95% CI: 1.13-3.76), and 2.37 (95% CI: 1.39-4.04), respectively. Among females, these characteristics remain important except the sources of drinking water. The history of herbal drug use and occupational lead exposure become the major risk factors for high blood lead with odds ratio of 2.94 (95% CI: 1.26-6.88) and 7.72 (95% CI: 3.51-16.99), respectively. In multivariate logistic regression analyses, we find that the risk factors for high blood lead in both genders include a history of herbal drug use and occupational lead exposure. Among males, the drinking water sources and factories in the neighboring areas are also significant factors for high blood lead. CONCLUSIONS For the goal of reducing prevalence of high blood lead by the year 2000, the improvement and monitoring of the working environment, the careful attention to herbal drug use and the lead-free drinking water sources should be executed as thoroughly as possible to reduce the probability of lead pollution.
Collapse
|
98
|
Abstract
From January 1990 to December 1995, a total of 22 patients with primary non-refluxing megaureter were treated in our hospital. The age distribution was 7 days to 8 years. The follow-up period was from 1 to 6 years. Nineteen of these 22 children underwent surgical intervention: 3 were operated upon at the time of diagnosis; the other 16 were initially treated conservatively, but underwent subsequent surgery due to impairment of renal function (13) or breakthrough infections (3). The failure rate for conservative management was about 84% (16/19): only 3 patients treated conservatively showed spontaneous resolution. The surgical success rate was 89.5% (17/19). The pathological change in the ureterovesical junction (UVJ) was adynamic in 13 cases and fibrotic in 6 (including 1 ectopic ureter). The postoperative complications were vesicoureteric reflux in 3 cases, with spontaneous resolution 6 months later, and UVJ stenosis in 1, which was resolved by reoperation. It is concluded that surgery is not necessary in every case, but still plays an important role in most cases. Early surgery can achieve good results and reduce renal damage.
Collapse
|
99
|
Lee MJ, Lee HC, Young W, Sheu JC, Chang PY, Wang NL. Conservative treatment of intra-abdominal abscess in children. ZHONGHUA MINGUO XIAO ER KE YI XUE HUI ZA ZHI [JOURNAL]. ZHONGHUA MINGUO XIAO ER KE YI XUE HUI 1998; 39:301-5. [PMID: 9823674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Fifty-three children under 18 years of age with sonogram-proved intra-abdominal abscess (IAA) were seen between July 1993 and June 1996 at the Department of Pediatrics of the Mackay Memorial Hospital, then were studied retrospectively. Following a course of conservative treatment and follow-up with serial sonographic studies, 42 (79.3%) patients responded favourably to antibiotics treatment without drainage procedure. The other 11 patients' condition deteriorated, and surgical intervention was performed. The gradual shrinkage and completely resolved periods of the abscesses averaged 27.9 days. The average duration of antibiotic treatment was 23.6 days, intravenously for average 12.2 days followed by oral treatment until the abscess was completely resolved (average 11.4 days). The intra-abdominal abscess recurred in 3 (5.7%) patients. The experience demonstrates that pediatric patients with an intra-abdominal abscess must be followed closely by sonography, and they can be managed successfully with appropriate antibiotics alone. Surgical intervention is still needed if symptoms and signs persist or deteriorate.
Collapse
|
100
|
Chen CP, Chern SR, Lin SP, Chang PY, Chang KM, Hsieh FJ. Concomitant chyloperitoneum and omental cysts presenting as fetal ascites with intra-abdominal cysts on prenatal ultrasound. Prenat Diagn 1998; 18:984-6. [PMID: 9793989 DOI: 10.1002/(sici)1097-0223(199809)18:9<984::aid-pd385>3.0.co;2-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|