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Lu MZ, Lan HL, Wang FF, Chang SJ, Wang YJ. Cell encapsulation with alginate and alpha-phenoxycinnamylidene-acetylated poly(allylamine). Biotechnol Bioeng 2000; 70:479-83. [PMID: 11042543 DOI: 10.1002/1097-0290(20001205)70:5<479::aid-bit1>3.0.co;2-e] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In general, microcapsules prepared from alginate and polycations lack mechanical strength because the interaction between alginate and polycations is ionic instead of covalent, which represents a much stronger bond. To increase the mechanical strength of the capsule, we prepared photosensitive microcapsules that could form covalent bonds between polymers in the capsular membrane by light irradiation. Two types of photosensitive poly(allylamine), with 5% and 10% of amino groups modified by alpha-phenoxycinnamylidene acetylchloride, were synthesized. Both photopolymers exhibited an absorption maximum at 325 nm and were capable of crosslinking upon light exposure. These photosensitive polymers were used for the preparation of microcapsules. The capsules formed from this photosensitive poly(allylamine) and alginate were strengthened significantly by light irradiation. Only 28% of the microcapsules prepared from the 5%-modified photopolymer fractured after 48 h of shaking at 150 rpm. This fracture percentage is much lower when compared with the 60% of capsules fractured when prepared from the untreated poly(allylamine). By using poly(allylamine) at 10% modification, the mechanical strength was improved only slightly, with 26% of capsules fractured. Analysis of the permeability test indicated that the photo-crosslinked capsular membrane was freely permeable to cytochrome c and myoglobin, but less permeable to serum albumin. The encapsulation method was used to entrap and culture IW32 mouse leukemia cells. The cells proliferated to a density of about 1.1 x 10(7) cells/mL in the capsules after 7 days of cultivation. Concurrently, the concentration of erythropoietin in the microcapsules increased to 800 mU/mL. This new encapsulation technique has great potential in the application of a bioindustrial cell-culturing process.
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Hwang SL, Yang YH, Lieu AS, Chuang MC, Chang SJ, Chang YY, Lin HJ, Howng SL. The conditional survival statistics for survivors with primary supratentorial astrocytic tumors. J Neurooncol 2000; 50:257-64. [PMID: 11263506 DOI: 10.1023/a:1006484220764] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Relative survival rates can offer a general description of tumor outcome and, traditionally, are used for surveillance and comparison purposes. However, they are not informative for individual tumor survivors. Conditional survival estimates can calculate the probability of surviving next some years given survival to a specific period of time after craniotomy for individual tumor survivors. However, clinically, they have not been used for predicting the tumor outcome. METHODS We calculated conditional probabilities of survival within 6 years after craniotomy in 112 patients with primary supratentorial astrocytic tumors and evaluated factors affecting the survival time more than 2 years after craniotomy. RESULTS Our data showed that the conditional probability of survival can predict yearly survival rate when patients survive for a specific period of time. The conditional survival rates within 6 years after craniotomy were always higher than those evaluated by relative survival rates. Overall, the longer the patients survived, the higher the conditional probabilities of surviving sixth year postoperatively were. CONCLUSION Our study demonstrates the conditional probabilities of survival have good availability and are important estimates for individual tumor survivors.
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Chang SJ, Leung CS, Wong KW, Sum J. A local training and pruning approach for neural networks. Int J Neural Syst 2000; 10:425-38. [PMID: 11307857 DOI: 10.1142/s0129065700000430] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The training of neural networks using the extended Kalman filter (EKF) algorithm is plagued by the drawback of high computational complexity and storage requirement that may become prohibitive even for networks of moderate size. In this paper, we present a local EKF training and pruning approach that can solve this problem. In particular, the by-products obtained along with the local EKF training can be utilized to measure the importance of the network weights. Comparing with the original global approach, the proposed local EKF training and pruning approach results in a much lower computational complexity and storage requirement. Hence, it is more practical in solving real world problems. The performance of the proposed algorithm is demonstrated on one medium- and one large-scale problems, namely, sunspot data prediction and handwritten digit recognition.
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Greenberg DP, Wong VK, Partridge S, Chang SJ, Jing J, Howe BJ, Ward JI. Immunogenicity of a Haemophilus influenzae type b-tetanus toxoid conjugate vaccine when mixed with a diphtheria-tetanus-acellular pertussis-hepatitis B combination vaccine. Pediatr Infect Dis J 2000; 19:1135-40. [PMID: 11144372 DOI: 10.1097/00006454-200012000-00003] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Combination vaccines are urgently needed to reduce the number of injections given to young children. The aim of the study was to evaluate the safety and immunogenicity of a combination vaccine that contains diphtheria and tetanus toxoids and acellular pertussis antigens (DTaP), recombinant hepatitis B surface antigen (HepB) and Haemophilus influenzae type b (Hib) polysaccharide conjugated to tetanus toxoid (PRP-T). METHODS Four hundred five infants were randomized equally to three groups and immunized at 2, 4 and 6 months of age with: (1) DTaP/HepB vaccine used to reconstitute lyophilized PRP-T vaccine and administered as a single injection; (2) DTaP/HepB vaccine and PRP-T vaccine administered as two separate injections; or (3) DTaP, HepB and PRP-T vaccines administered as three separate injections. Safety was closely monitored, and blood specimens were obtained to assess antibody responses to each vaccine antigen. RESULTS All study vaccines were well-tolerated, and the rates of systemic and injection site reactions were similar between groups. After the third dose the geometric mean antibody concentrations to Hib were significantly lower in subjects in Group 1 (1.63 microg/ml) compared with subjects in Groups 2 and 3 (6.26 and 6.15 microg/ml, respectively; P < 0.0001). Subjects with antibody concentrations <1.0 microg/ml after the third dose responded well to a booster dose of Hib conjugate vaccine given at 11 to 15 months of age (41 of 44 with anti-PRP > or = 1.0 microg/ml). Differences between groups for antibody responses to the other vaccine components were not clinically significant. CONCLUSIONS Infants given a combined DTaP/ HepB/PRP-T vaccine experienced a significantly lower antibody response to the PRP-T component than infants given PRP-T vaccine as a separate injection. However, the immune response to a booster dose of Hib conjugate vaccine indicated the presence of immunologic memory.
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Jeon BH, Kim CS, Kim HS, Park JB, Nam KY, Chang SJ. Effect of Korean red ginseng on blood pressure and nitric oxide production. Acta Pharmacol Sin 2000; 21:1095-100. [PMID: 11603282] [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] Open
Abstract
AIM To investigate the effect of crude saponin and nonsaponin fraction of Korean red ginseng (KRG) on the blood pressure and nitric oxide (NO) production in the conscious rats and cultured endothelial cell line, ECV 304 cells. METHODS Systolic blood pressure and heart rate were monitored in the conscious rats. Nitric oxide levels and the expression of nitric oxide synthase were measured by a spectrophotometric assay using Griess reagents and Western blotting, respectively. Nitric-oxide synthase activity was measured based on the conversion rate of [3H]arginine to [3H]citrulline. RESULTS Systolic blood pressure was decreased by crude saponin (100 mg/kg, i.v.) of KRG in the conscious control and one-kidney, one-clip Goldblatt hypertensive (1K, 1C-GBH) rats. The hypotensive effect induced by crude saponin of KRG reached maximum at 2-4 min and slowly recovered after 20 min to the initial level in both groups. Crude saponin of KRG induced tachycardia in the conscious rats but induced bradycardia in the anesthetized rats. In contrast to crude saponin of KRG, hypotensive effect induced by saponin-free fraction was minimal. Nitric oxide concentrations were increased by the treatment of crude saponin in conscious rats as well as in the cultured ECV 304 cells. The protein expression level of endothelial constitutive nitric-oxide synthase (eNOS) in the aorta of rats was not increased by crude saponin (100 mg/kg, i.p. for 3 d). However, nitric-oxide synthase activity was increased by crude saponin of KRG in the aortic homogenate of rats. CONCLUSION The hypotensive effect of red ginseng is mainly due to saponin fraction of KRG in the conscious rats, and this effect may be due to an increase in the nitric-oxide production by KRG.
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Abstract
The presence of human papillomavirus DNA in cholesteatoma may have some role in the development of middle ear cholesteatoma as well as in papilloma. In the present study, polymerase chain reaction and in situ hybridization with human papillomavirus (HPV)-6 and -11 DNA probes were used to detect the presence of HPV DNA in 32 human middle ear cholesteatomas. Only one specimen contained HPV-6 DNA. Although its occurrence may have been coincidental, it is also possible that the hyperproliferative epithelium of cholesteatomas might have some relationship with HPV infections.
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Jeon BH, Kim CS, Park KS, Lee JW, Park JB, Kim KJ, Kim SH, Chang SJ, Nam KY. Effect of Korea red ginseng on the blood pressure in conscious hypertensive rats. GENERAL PHARMACOLOGY 2000; 35:135-41. [PMID: 11744235 DOI: 10.1016/s0306-3623(01)00096-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The change of blood pressure and heart rate after intravenous injection of Korea red ginseng (KRG) were studied in the conscious normotensive and one-kidney, one-clip Goldblatt hypertensive (1K, 1C-GBH) rats. Crude saponin (CS) of KRG (50, 100 mg/kg i.v.) induced a hypotensive effect and bradycardia in a dose-dependent manner in the anesthetized rats. On the other hand, CS of KRG (100 mg/kg) induced a hypotensive effect and reflex tachycardia in the conscious rats. Saponin-free fraction (SFF) of KRG did not affect them in the anesthetized normotensive rats (P>.05). The maximal hypotensive effect by CS of KRG in the conscious 1K, 1C-GBH hypertensive rats and L-nitroarginine methyl ester (L-NAME, 40 mg/kg)-treated conscious hypertensive rats was not different from that of conscious normotensive rats (Delta 31.6+/-6.3, Delta 27.5+/-5.8 vs. Delta 26.7+/-4.3 mmHg, P>.05). However, pretreatment of L-NAME significantly inhibited the reflex tachycardia by CS of KRG (70.8+/-7.0 vs. 30.6+/-15.0 bpm, P<.05). Hemolysate-sensitive nitric oxide (NO) current by the CS of KRG was greater than that of the SFF of KRG (651.9+/-128.2 pA for CS and 164.9+/-92.5 pA for SFF, P<.001). These findings suggest that KRG has a hypotensive effect and its effect may be due to saponin fraction of KRG in the conscious rats. The releasing effect of NO of KRG, like NO donor, may be partly contributed to the hypotensive effect of KRG.
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Chang SJ. Vitamin B6 antagonists alter the function and ultrastructure of mice endothelial cells. J Nutr Sci Vitaminol (Tokyo) 2000; 46:149-53. [PMID: 11185649 DOI: 10.3177/jnsv.46.149] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Vitamin B6, is necessary for normal membrane function and stability. Here we studied both the function and ultrastructure of aortic and arterial endothelial cells (ECs) in vitamin B6 deficient mice induced by vitamin B6 antagonists, 4-deoxypyridoxine x HCl (dPN x HCl), and isonicotinylhydrazide (INH). Mice were fed with normal laboratory chow and divided into three groups according to their drinking water. Mice in group I had distilled water and served as a control; group II had 0.1 mg dPN x HCl/mL H2O; and group III had 0.4 mg INH/mL H2O. After 5 mo, plasma concentrations of B6 vitamers pyridoxal-5'-phosphate (PLP) and pyridoxal (PL) were analyzed by HPLC. With the arachidonic acid (AA) as a precursor, prostacyclin (PGI2) production from ECs assayed by thin-layer chromatography (TLC) was used as an indicator of endothelial function. Aorta and arteriole from foot pad were removed, stained with osmium tetraoxide, and examined under transmission electron microscopy (TEM) to study the ultrastructure of ECs. The results showed that plasma concentrations of PLP, PL, and total B6 were the lowest for mice fed with INH. followed by that with dPN x HCl, compared with that of control. PGI2 production was paralleled with the plasma vitamin B6 status, with the lowest level for INH, followed by the dPN-treated group. Abnormalities in the ultrastructure of ECs were found in both dPN x HCl and INH groups, including cells detached from underlying elastic tissue, with prominent pinocytotic vesicles and swelling and/or indistinct cristae of mitochondria. These results suggest that vitamin B6 antagonists induce a deficient status that alters the function and the ultrastructure of ECs detrimental to vascular disease.
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Keller M, Deveikis A, Cutillar-Garcia M, Gagajena A, Elkins K, Plaeger S, Bryson Y, Kaplan A, Zangwill K, Chang SJ. Pneumococcal and influenza immunization and human immunodeficiency virus load in children. Pediatr Infect Dis J 2000; 19:613-8. [PMID: 10917218 DOI: 10.1097/00006454-200007000-00006] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE HIV-infected children receiving influenza vaccine, pneumococcal vaccine and both vaccines concurrently were studied to examine the effect of immunization on plasma HIV viral load. METHODS Thirteen children received immunizations: pneumococcal vaccine, 5; pneumococcal and influenza vaccines, 7; and influenza vaccine, 1. Most patients (12 of 13) were receiving combination reverse transcriptase inhibitor antiretroviral therapy without protease inhibitors at the time of immunization. Baseline plasma HIV RNA was determined 1 month prior (11 of 13), 2 weeks prior (12 of 13) and on the day of immunization (12 of 13). Plasma HIV RNA was assayed at 2 weeks (11 of 13), 4 weeks (12 of 13) and 3 months (5 of 13) after immunization. T cell activation markers (HLA-DR+, CD38+ and CD45RO+, CD28+) were examined for both CD4+ and CD8+ lymphocytes on the day of immunization and 2 weeks after immunization for 11 children. RESULTS Only one child developed a >0.5-log increase in viral load at any time after immunization. There was no correlation between an increase in viral load and antibody response to pneumococcal vaccine. At least one activation marker increased (> 10%) for two children receiving pneumococcal vaccine and two children receiving pneumococcal and influenza vaccines. One of these children experienced an increase in viral load. CONCLUSION Immunization with pneumococcal and influenza vaccines, alone or in combination, is rarely associated with a significant increase in HIV plasma RNA in children receiving combination antiretroviral therapy.
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Chang SJ, Ma ZH, Wang XF, Li L, Zhou GH. [High-level expression of BYDV GAV coat protein gene in Escherichia coli]. SHENG WU GONG CHENG XUE BAO = CHINESE JOURNAL OF BIOTECHNOLOGY 2000; 16:400-2. [PMID: 11059290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The IPTG-inducible expression vector containing the BYDV GAV coat protein gene was constructed and transferred into E. coli BL21(DE3). High-level expression of the specific protein was achieved by IPTG induction. The results of SDS-PAGE and Western blotting show that the expression product which accumulates 19.5% of the total cellular proteins estimated by scanning is 24 kD BYDV GAV coat protein plus eleven amino acids of pET-5a.
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Chen MR, Chang SJ, Huang H, Chen JY. A protein kinase activity associated with Epstein-Barr virus BGLF4 phosphorylates the viral early antigen EA-D in vitro. J Virol 2000; 74:3093-104. [PMID: 10708424 PMCID: PMC111808 DOI: 10.1128/jvi.74.7.3093-3104.2000] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Epstein-Barr virus (EBV) open reading frame BGLF4 was identified as a potential Ser/Thr protein kinase gene through the recognition of amino acid sequence motifs characteristic of conserved regions within the catalytic domains of protein kinases. In order to investigate this potential kinase activity, BGLF4 was expressed in Escherichia coli and the purified protein was used to generate a specific antiserum. Recombinant vaccinia virus vTF7-3, which expresses the T7 RNA polymerase, was used to infect 293 and 293T cells after transient transfection with a plasmid containing BGLF4 under the control of the T7 promoter. Autophosphorylation of the BGLF4 protein was demonstrated using the specific antiserum in an immune complex kinase assay. In addition, EBNA-1-tagged BGLF4 and EBNA-1 monoclonal antibody 5C11 were used to demonstrate the specificity of the kinase activity and to locate BGLF4 in the cytoplasm of transfected cells. Manganese ions were found to be essential for autophosphorylation of BGLF4, and magnesium can stimulate the activity. BGLF4 can utilize GTP, in addition to ATP, as a phosphate donor in this assay. BGLF4 can phosphorylate histone and casein in vitro. Among the potential viral protein substrates we examined, the EBV early antigen (EA-D, BMRF1), a DNA polymerase accessory factor and an important transactivator during lytic infection, was found to be phosphorylated by BGLF4 in vitro. Amino acids 1 to 26 of BGLF4, but not the predicted conserved catalytic domain, were found to be essential for autophosphorylation of BGLF4.
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Abstract
Alpha-tocopherol is known to inhibit platelet aggregation but the mechanism responsible for this has not been elucidated. Glycoprotein IIb (GPIIb) is the alpha-subunit of the platelet membrane protein GPIIb/IIIa, which functions as a specific receptor for platelet aggregation. Human erythroleukemia (HEL) cells are megakaryocytelike and express the megakaryocyte-specific GPIIb gene. To understand the molecular mechanism of alpha-tocopherol on antiaggregation, we analyzed the effect of physiologically relevant concentrations of alpha-tocopherol on the expression of human GPIIb promoter in HEL cells. The enhancement of tetradecanoylphoerbol-12,13-acetate (TPA)-mediated transient and optimal expression of plasmids was achieved by adding 10(-7)-M TPA in the medium 24 h before lipofection. Transient expression of GPIIb promoter was determined in transfected cells pretreated with various concentrations of alpha-tocopherol. Our data shows that the GPIIb promoter activity was downregulated to 55, 23, 27, 20, and 15% in the presence of 10, 20, 40, 80, and 120 microg/ml of alpha-tocopherol, respectively, as compared with that in the absence of alpha-tocopherol. The downregulation of alpha-tocopherol on the TPA-mediated GPIIb promoter activity may result in a reduction of GPIIb protein expression and thus contribute to antiplatelet aggregation.
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Lu FM, Yuan HS, Hsu YC, Chang SJ, Chak KF. Hierarchical order of critical residues on the immunity-determining region of the Im7 protein which confer specific immunity to its cognate colicin. Biochem Biophys Res Commun 1999; 264:69-75. [PMID: 10527843 DOI: 10.1006/bbrc.1999.1424] [Citation(s) in RCA: 5] [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
The directed mutagenesis study of the Im7 protein of colicin E7 revealed that three residues, D31, D35, and E39, located in the loop 1 and helix 2 regions of the protein were critical for initiating the complex formation with its cognate colicin E7. Interestingly, the importance of these three critical residues in conferring specific immunity to its own colicin was exhibited in a hierarchical order, respectively. Moreover, we found that existence of the three critical residues was common among the DNase-type Im proteins. Most likely the three residues of the DNase-type immunity proteins are critical for initiating the unique protein-protein interactions with their cognate colicin. In addition, replacement of the helix 2 of Im7 by the corresponding region of Im8 produced a phenotype of the mutant protein very similar to that of Im8. This result suggests that the DNase-type Im proteins indeed share a "homologous-structural framework" and evolution of the Im proteins may be engendered by minor amino acid changes in this specific immunity-determining region without causing structural alteration of the proteins.
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Chao WY, Wang CF, Chang SJ. Ventilation tube in adults with middle-ear effusion. THE JOURNAL OF OTOLARYNGOLOGY 1999; 28:278-81. [PMID: 10579158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
OBJECTIVE This study was conducted to analyze the data concerning otitis media with effusion (OME) to configure its etiology, symptomatology, and outcome in adults. METHOD A retrospective study of 198 consecutive cases (260 ears) of OME was conducted between July 1988 and June 1996. All of the patients were older than 16 years and were diagnosed for the first time. Tympanograms, initial symptoms, underlying diseases, extrusion of the ventilation tube, and recurrence rate of effusion were analyzed. RESULTS Sinusitis was usually seen in patients 16 to 29 and over 60 years old, whereas nasopharyngeal carcinoma was prevalent in patients 30 to 59 years old. Ear stuffiness (75.3%) was the most prevalent initial symptom, followed by hearing impairment (74.2%). One hundred seventy-five ears from 132 patients had been followed up for more than 2 years. In four ears, ventilation tubes were removed by instrument; the ventilation tubes in the remaining 171 ears of 128 patients extruded spontaneously within 20 months (8.6 months on average). Recurrence of effusion within 2 years was noted in 78.8% (78/99 ears) of patients with head and neck tumours and in 27.3% (12/44 ears) of patients with sinusitis. CONCLUSION Nasopharyngeal carcinoma and sinusitis were the main etiologies of OME in adults. In addition to treatment of sinusitis, nasopharyngeal check-up is mandatory in adults with OME.
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Chou HY, Peng TY, Chang SJ, Hsu YL, Wu JL. Effect of heavy metal stressors and salinity shock on the susceptibility of grouper (Epinephelus sp.) to infectious pancreatic necrosis virus. Virus Res 1999; 63:121-9. [PMID: 10509723 DOI: 10.1016/s0168-1702(99)00065-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In the present study, attempts were made to clarify the effect of heavy metal stressors and salinity shock on the disease susceptibility of grouper fry (Epinephelus sp.) to infectious pancreatic necrosis virus (IPNV) infection. Zinc, cadmium and copper (5 ppm ZnCl2, 3 ppm CdCl2 and 1 ppm CuCl2) were used to treat groupers before and after virus infection. Cumulative mortalities in the experimental groups were 96-100% within 42 days. Only 5-15% mortalities were observed in most of the groups that were exposed to either heavy metals or virus infection alone. Subsequently, virus was re-isolated from the experimentally infected groupers, and copper concentration was measured in fish that had been exposed to CuCl2. We also investigated the effect of salinity shock (i.e. an abrupt change of salinity level from 33 ppt to either 40 ppt or 20 ppt) on susceptibility of grouper to IPNV. Similar results were obtained, mortalities of groupers in the experimental groups reached 80-100%. The results of the present study suggest that an IPN virus with only low pathogenicity could cause high mortality in groupers when combined with environmental stress.
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Chang SJ, Chang JG, Chen CJ, Wang JC, Ou TT, Chang KL, Ko YC. Identification of a new single nucleotide substitution on the hypoxanthine-guanine phosphoribosyltransferase gene (HPRT(Tsou) from a Taiwanese aboriginal family with severe gout. J Rheumatol 1999; 26:1802-7. [PMID: 10451080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
OBJECTIVE A new single nucleotide change of the hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene on coding region has been identified from a Taiwanese aboriginal family with gout. The mutation was used to screen 27 members of the family, 22 Tsou, 70 Atayal, and 76 Bunun children, the elders for whom had been found to have a high prevalence of gout. METHODS An entire peptide of HPRT coding region was directly sequenced from the cDNA of a patient with severe gout, and by using polymerase chain reaction and restriction fragment length polymorphism to screen the other participants. RESULTS A new nucleotide change located at nucleotide 152 (G to A transition) was found that predicted an arginine to glutamine substitution at amino acid 51. This variant was named HPRT(Tsou), and was found in 3 women and 3 men among the patient's 7 siblings, 2 boys and 2 girls among the 8 children of the siblings, and one female Tsou (4.5%, 1/22) and one female Atayal (1.4%, 1/70). The serum uric acid concentration among male HPRT(Tsou) carriers in the patient's family was significantly higher than among those who had at least one HPRT gene that did not have HPRT(Tsou). CONCLUSION We found that the HPRT(Tsou) gene variant is partially responsible for the hyperuricemia in an aboriginal population in Taiwan known for a high incidence of gout.
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Chang CJ, Lin CH, Lee CT, Chang SJ, Ko YC, Liu HW. Hepatitis C virus infection among short-term intravenous drug users in southern Taiwan. Eur J Epidemiol 1999; 15:597-601. [PMID: 10543348 DOI: 10.1023/a:1007662315835] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The purpose of this study was to determine the correlation between the prevalence of hepatitis C virus (HCV) infection with duration of drug use and other risk factors among drug users. This survey covered 899 male drug users from Kaohsiung Narcotic Abstention Institute and Kaohsiung prison. The prevalence of positive anti-HCV was 67.2% among intravenous drug users (IVDU) and 14.7% among non-intravenous drug users (non-IVDU). Among intravenous (IV) drug users, age and duration of drug use were independently related to HCV seropositivity. Seroprevalence rate for HCV in the IVDU group increased with increasing duration of injection use within the first seven years of drug use. However, the steepest trajectory in seroprevalence of HCV infection occurred within the first four months. Due to the high rate of HCV infection among drug users, investigation of risk behaviors should be routine in such a group. A high frequency of HCV infection was also found among short-term injectors, which indicated that early risk reduction intervention was an important measure in moderating HCV infection.
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Chang SJ. Adequacy of maternal pyridoxine supplementation during pregnancy in relation to the vitamin B6 status and growth of neonates at birth. J Nutr Sci Vitaminol (Tokyo) 1999; 45:449-58. [PMID: 10575635 DOI: 10.3177/jnsv.45.449] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
To evaluate the adequacy of maternal pyridoxine supplementation during pregnancy for both maternal and neonatal status at birth, vitamin B6 status, assessed by plasma pyridoxal phosphate (PLP), pyridoxal (PL) and total aldehyde vitamer (PLP + PL) concentrations, and the growth of neonates, including weight, length, head and chest circumferences, were examined for 209 neonates whose mothers were supplemented with 0, 1, 2 or 3 mg pyridoxine.HCl (PN.HCl)/d during pregnancy. Maternal PN.HCl supplementations were positively correlated to both maternal (r = 0.62) and cord (r = 0.78) plasma PLP concentrations (p < 0.0001). Mothers supplemented with 2 or 3 mg/d PN.HCl had significantly higher plasma concentrations of PLP and total B6 aldehyde vitamer in maternal and cord blood compared with those receiving 0 or 1 mg PN.HCl/d. A growth benefit for neonates whose mothers had maternal and cord plasma PLP concentrations > or = 40 nM was revealed by the maternal supplementation of 2 mg PN.HCl/d during pregnancy. Thus, in healthy pregnant women, according to our study, a daily supplement of 2 mg PN.HCl provides the adequacy of maternal and neonatal vitamin B6 status and the satisfactory growth of neonates at birth.
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Chang SJ, Chuang HJ, Chen HH. Vitamin B6 down-regulates the expression of human GPIIb gene. J Nutr Sci Vitaminol (Tokyo) 1999; 45:471-9. [PMID: 10575637 DOI: 10.3177/jnsv.45.471] [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: 11/27/2022]
Abstract
Glycoprotein IIb (GPIIb) is the alpha-subunit of the platelet membrane receptor GPIIb/IIIa, which plays a major role in platelet aggregation. Vitamin B6 has been reported to be an antiaggregative agent, although its mechanism is not well known. To understand the molecular mechanism of vitamin B6 on antiaggregation, we analyzed the effects of various forms of vitamin B6 on the expression of human GPIIb promoter using chloramphenicol acetyl transferase (CAT) as the reporter gene. The GPIIb promoter region was amplified by polymerase chain reaction (PCR), cloned into pBLCAT3 to drive the CAT reporter gene and transfected into human erythroleukemia (HEL) cells. Transient expression of the GPIIb promoter was determined after transfected cells were treated with 1 microM pyridoxine (PN), pyridoxal (PL), pyridoxal-5-phosphate (PLP), or 4-deoxypyridoxine (4-dex) for 48 h. Our results show that the GPIIb promoter activity was down-regulated to 54, 35 and 63% in the presence of PN, PL and PLP, respectively, as compared to an untreated control whose promoter activity was 100%. However, no adverse effect on GPIIb promoter was detected by 4-dex, which is an antagonist of vitamin B6. The down-regulation effect of vitamin B6 on GPIIb promoter activity may lead to a reduction of GPIIb protein expression and thus be detrimental to platelet aggregation.
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Chang SJ, Lee CH, Wang YJ. Microcapsules prepared from alginate and a photosensitive poly(L-lysine). JOURNAL OF BIOMATERIALS SCIENCE. POLYMER EDITION 1999; 10:531-42. [PMID: 10357264 DOI: 10.1163/156856299x00469] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A photosensitive polymer, alpha-phenylcinnamylideneacetylated poly(L-lysine), was synthesized and characterized. This photosensitive poly(L-lysine) had 10% of its lysine residues reacted with alpha-phenylcinnamylidene acetyl group and displayed an absorption maximum at 329 nm. The photosensitive poly(L-lysine) was used for the preparation of microcapsules. The capsules formed from this photosensitive poly(L-lysine) and alginate were strengthened significantly by light irradiation. The photo cross-linked capsular membrane was permeable to proteins with mass transfer rate in the descending order: cytochrome C, myoglobin. and serum albumin. GH3 (a rat pituitary tumor cell line) cells were encapsulated and cultured with this microencapsulation system. The cells proliferated to a density of about 4 x 10(5) cells ml(-1) in the capsules after 6 days cultivation.
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Chang SJ, Kuo SM, Lan JW, Wang YJ. Amination of polycarbonate surface and its application for cell attachment. ARTIFICIAL CELLS, BLOOD SUBSTITUTES, AND IMMOBILIZATION BIOTECHNOLOGY 1999; 27:229-44. [PMID: 10226686 DOI: 10.3109/10731199909117696] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The polycarbonate sheet was modified with ammonia gaseous plasma and characterized by the contact angle measurement and ESCA analysis. The contact angles decreased significantly from 77 degrees to about 20 degrees-40 degrees, indicate that the polycarbonate sheet become more hydrophilic after plasma treatment. The ESCA analysis results showed that the hydrophilicity was mainly derived from the amino groups on the modified surface. In this study, a flow-chamber system was also constructed to evaluate the 3T3 fibroblast cells attachment phenomena on these modified sheets. Before the experimental run, the parameters of inoculated cell number and cell passage were examined previously. The results revealed that these two parameters are independent in shear experiment. And besides, 3-hours plating time has the better adhering fraction. The experimental results showed that the 3T3 fibroblast cells adhesion strength increased significantly on the plasma modified sheet.
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Abstract
Although stroke is a great public health challenge in Korea, there have have been few epidemiologic studies of the risk factors stroke. A case-control study was performed to evaluate the risk factors for hemorrhagic stroke in Wonju, Korea. Ninety-five subarachnoid hemorrhage (SAH) and 102 intracerebral hemorrhage (ICH) patients aged 21-86 years, and 267 controls were recruited among the inpatients of Wonju Christian Hospital during 1994-1995. Information was gathered through interview and examinations. After adjustment for age and sex, family and past history of hypertension, drinking habits, age of menarche, height, weight, body mass index, waist and hip circumference, earlobe crease, prothrombin time, white blood cell count, hemoglobin, and total cholesterol were all found to be significantly associated with both SAH and ICH. The risk factor significantly associated only with ICH was smoking habits. In multiple logistics analyses, the independent risk factors for SAH and ICH were the same. Those included family and past history of hypertension, age of menarche, earlobe crease, prothrombin time, white blood cell count, hemoglobin and total cholesterol. In general, the risk factors for SAH and ICH were similar with each other, except smoking habits. Risk factors found in this study congruent with previous studies were family and past history of hypertension, drinking habits, body mass index, prothrombin time, white blood cell count, and hemoglobin. Those incongruent or rather newly found were age of menarche, a big physique, earlobe crease, and total cholesterol.
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Abstract
A flat depressed early colon cancer (FDEC) is characterized by non-polypoid growth pattern, no association of adenomatous tissues and a tendency of even small lesions toward submucosal invasion and lymph node metastasis. It supports de novo carcinogenesis of colorectal cancer, although most colorectal cancers arise in pre-existing adenoma (adenoma-carcinoma sequence). There have been few reports of small depressed cancers because of the difficulty in colonoscopic detection and the rapid development to ulcerating advanced cancers. We report a case of flat depressed early colon cancer confined to mucosa detected by indigo carmine contrast colonoscopy.
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Chang SJ, Ko YC, Wang TN, Chang FT, Cinkotai FF, Chen CJ. High prevalence of gout and related risk factors in Taiwan's Aborigines. J Rheumatol Suppl 1997; 24:1364-9. [PMID: 9228138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To estimate the prevalence of gout and to examine its risk factors among Taiwan's Aborigines compared with non-Aborigines. METHODS Data were collected from persons older than 40 years living in 3 aboriginal and 2 non-aboriginal districts in Taiwan by a community survey. Cases of gout were identified from self-reporting of a doctor's diagnosis based on clinical criteria. Baseline variables and biochemical data were examined as risk factors for the development of gout. RESULTS The prevalence of gout history was found to be 15.2% (25/165) and 4.8% (11/231) among aboriginal men and women, respectively, compared with a prevalence rate of 0.3% among non-Aborigines. A logistic regression model showed that aboriginal men older than 60 years with hyperuricemia were more severely affected by gout than any other group (p < 0.05). CONCLUSION A high prevalence of gout among Taiwanese Aborigines was observed in this study and race was the most significant risk factor associated with the disease.
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Chao WY, Tseng HZ, Chang SJ. Eustachian tube dysfunction in the pathogenesis of cholesteatoma: clinical considerations. THE JOURNAL OF OTOLARYNGOLOGY 1996; 25:334-8. [PMID: 8902694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE This study was conducted to gain insight into the surgical management of cholesteatomas to prevent postoperative retraction of the tympanic membrane. DESIGN A retrospective chart review of patients presenting between July 1988 and July 1992 was conducted. METHOD Clinical observations were made on 85 ears from 81 patients who had tympanoplasty with mastoidectomy for middle ear cholesteatoma, with ossicular reconstruction if necessary, with a subsequent follow-up period of 36 to 84 months (mean, 60 +/- 13 months). RESULTS The tympanic membrane in several cases became gradually retracted postoperatively; retraction generally commenced along the margin of the cartilage used for repairing the scutum defect, and was noted as early as 9 months, and after 5 years' follow-up, in as much as 66% in the 44 ears operated. CONCLUSIONS Eustachian tube dysfunction was common postoperatively in cholesteatomatous ears; however, whether it was the etiology or the sequela of a cholesteatoma could not be deduced. Since a retraction pocket in the tympanic membrane can develop into a cholesteatoma, it may account for some cases with recurrence of cholesteatoma postoperatively. Therefore, the cartilage/perichondrium composite graft for repairing the bone defect should be as large as possible.
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