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Jang TJ, Kim DI, Shin YM, Chang HK, Yang CH. p16(INK4a) Promoter hypermethylation of non-tumorous tissue adjacent to gastric cancer is correlated with glandular atrophy and chronic inflammation. Int J Cancer 2001; 93:629-34. [PMID: 11477571 DOI: 10.1002/ijc.1394] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The p16(INK4a) tumor suppressor gene can be inactivated by promoter region hypermethylation in many tumor types including gastric cancers. However, p16(INK4a) promoter hypermethylation in the surrounding non-tumorous tissues of gastric cancers has not been studied in detail. We therefore examined 46 gastric cancers, corresponding adjacent non-tumorous tissue samples and 8 gastric tissue samples of chronic gastritis by performing methylation-specific polymerase chain reaction, and we analyzed p16(INK4a) protein expression using immunohistochemistry and Western blot. p16(INK4a) promoter hypermethylation was observed in 43% of gastric cancers and 59% of adjacent non-tumorous tissues; however, none of the samples retrieved from the chronic gastritis patients displayed p16(INK4a) promoter hypermethylation. Gastric cancers showed an inverse correlation between vascular invasion and p16(INK4a) promoter hypermethylation, and adjacent non-tumorous tissues displayed a close association among the grade of chronic inflammation, presence of glandular atrophy and p16(INK4a) promoter hypermethylation. p16(INK4a) expression was markedly decreased in samples with p16(INK4a) promoter hypermethylation when compared with samples without p16(INK4a) promoter hypermethylation. These results suggest that p16(INK4a) promoter hypermethylation is an early and frequent event in gastric carcinogenesis and may serve as a new prognostic biomarker for the risk of gastric cancers.
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102
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Yang CH, Yang CH, Chuang LY, Truong TK. The application of the neural network on Morse code recognition for users with physical impairments. Proc Inst Mech Eng H 2001; 215:325-31. [PMID: 11436276 DOI: 10.1243/0954411011535920] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Morse code is a simple, speedy and low cost means of communication composed of a series of dots, dashes and space intervals. Each tone element (either a dot, dash or space interval) is transmitted by sending a signal for a defined length of time. This poses a challenge as the automatic recognition of Morse code is dependent upon maintaining a stable typing rate. In this paper, a suitable adaptive automatic recognition method, combining the least-mean-square (LMS) algorithm with a neural network, was applied to this problem. The method presented in this paper is divided into five modules: space recognition, tone recognition, learning process, adaptive processing and character recognition. Statistical analyses demonstrated that the proposed method elicited a better recognition rate in comparison with other methods in the literature.
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103
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Chu CY, Yang CH, Chiu HC. Inflammation of seborrheic keratoses due to docetaxel treatment. Acta Derm Venereol 2001; 81:316-7. [PMID: 11720193 DOI: 10.1080/00015550152573092] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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104
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Aubert D, Chen L, Moon YH, Martin D, Castle LA, Yang CH, Sung ZR. EMF1, a novel protein involved in the control of shoot architecture and flowering in Arabidopsis. THE PLANT CELL 2001; 13:1865-75. [PMID: 11487698 PMCID: PMC139134 DOI: 10.1105/tpc.010094] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2001] [Accepted: 05/29/2001] [Indexed: 05/17/2023]
Abstract
Shoot architecture and flowering time in angiosperms depend on the balanced expression of a large number of flowering time and flower meristem identity genes. Loss-of-function mutations in the Arabidopsis EMBRYONIC FLOWER (EMF) genes cause Arabidopsis to eliminate rosette shoot growth and transform the apical meristem from indeterminate to determinate growth by producing a single terminal flower on all nodes. We have identified the EMF1 gene by positional cloning. The deduced polypeptide has no homology with any protein of known function except a putative protein in the rice genome with which EMF1 shares common motifs that include nuclear localization signals, P-loop, and LXXLL elements. Alteration of EMF1 expression in transgenic plants caused progressive changes in flowering time, shoot determinacy, and inflorescence architecture. EMF1 and its related sequence may belong to a new class of proteins that function as transcriptional regulators of phase transition during shoot development.
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105
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Aubert D, Chen L, Moon YH, Martin D, Castle LA, Yang CH, Sung ZR. EMF1, a novel protein involved in the control of shoot architecture and flowering in Arabidopsis. THE PLANT CELL 2001. [PMID: 11487698 DOI: 10.1105/tpc.13.8.1865] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Shoot architecture and flowering time in angiosperms depend on the balanced expression of a large number of flowering time and flower meristem identity genes. Loss-of-function mutations in the Arabidopsis EMBRYONIC FLOWER (EMF) genes cause Arabidopsis to eliminate rosette shoot growth and transform the apical meristem from indeterminate to determinate growth by producing a single terminal flower on all nodes. We have identified the EMF1 gene by positional cloning. The deduced polypeptide has no homology with any protein of known function except a putative protein in the rice genome with which EMF1 shares common motifs that include nuclear localization signals, P-loop, and LXXLL elements. Alteration of EMF1 expression in transgenic plants caused progressive changes in flowering time, shoot determinacy, and inflorescence architecture. EMF1 and its related sequence may belong to a new class of proteins that function as transcriptional regulators of phase transition during shoot development.
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106
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Weng SF, Tai PM, Yang CH, Wu CD, Tsai WJ, Lin JW, Tseng YH. Characterization of stress-responsive genes, hrcA-grpE-dnaK-dnaJ, from phytopathogenic Xanthomonas campestris. Arch Microbiol 2001; 176:121-8. [PMID: 11479711 DOI: 10.1007/s002030100302] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2000] [Accepted: 05/07/2001] [Indexed: 11/29/2022]
Abstract
Sequencing of a 6.4-kb DNA fragment, cloned from the plant pathogenic bacterium Xanthomonas campestris pv. campestris 17 revealed five ORFs whose deduced amino acid sequences show strong similarities to the bacterial HrcA, GrpE, DnaK, DnaJ, and PdxK. The four heat shock genes are organized in the order hrcA-grpE-dnaK-dnaJ, a genome organization found in many gram-positive bacteria, but only in one gram-negative species (Xylella fastidiosa). These observations suggest that the HrcA-CIRCE system, comprising at least four genes arranged in this order, already existed for the regulation of stress responses before bacteria diverged into gram-negative and gram-positive groups. Primer-extension results suggested the presence of promoters at the regions upstream of grpE and dnaK. In the presence of stress, heat or ethanol (4%), the X. campestris pv. campestris 17 grpE and dnaK promoters were induced two- to three-fold over controls. Since the grpE and dnaK promoters possess E. coli sigma(32) promoter-like sequences, they are functional in E. coli, although at levels much lower than in X. campestris pv. campestris 17. Furthermore, expression of the X. campestris pv. campestris 17 dnaK promoter in E. coli was elevated by the cloned X. campestris sigma(32) gene, indicating that the cognate sigma(32) works more efficiently for the X. campestris promoters.
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MESH Headings
- Bacterial Proteins/genetics
- Base Sequence
- Cloning, Molecular
- DNA-Binding Proteins
- Escherichia coli/genetics
- Escherichia coli Proteins
- Gene Expression Regulation, Bacterial
- Gene Order/genetics
- Genes, Bacterial/genetics
- Genes, Reporter
- HSP40 Heat-Shock Proteins
- HSP70 Heat-Shock Proteins/genetics
- Heat-Shock Proteins/genetics
- Heat-Shock Response/genetics
- Hot Temperature
- Open Reading Frames/genetics
- Operon/genetics
- Promoter Regions, Genetic/genetics
- RNA, Bacterial/analysis
- RNA, Bacterial/genetics
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- Regulatory Sequences, Nucleic Acid
- Repressor Proteins/genetics
- Sequence Analysis, DNA
- Species Specificity
- Transcription Initiation Site
- Transcription, Genetic
- Xanthomonas campestris/genetics
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Ibekwe AM, Papiernik SK, Gan J, Yates SR, Yang CH, Crowley DE. Impact of fumigants on soil microbial communities. Appl Environ Microbiol 2001; 67:3245-57. [PMID: 11425748 PMCID: PMC93007 DOI: 10.1128/aem.67.7.3245-3257.2001] [Citation(s) in RCA: 198] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Agricultural soils are typically fumigated to provide effective control of nematodes, soilborne pathogens, and weeds in preparation for planting of high-value cash crops. The ability of soil microbial communities to recover after treatment with fumigants was examined using culture-dependent (Biolog) and culture-independent (phospholipid fatty acid [PLFA] analysis and denaturing gradient gel electrophoresis [DGGE] of 16S ribosomal DNA [rDNA] fragments amplified directly from soil DNA) approaches. Changes in soil microbial community structure were examined in a microcosm experiment following the application of methyl bromide (MeBr), methyl isothiocyanate, 1,3-dichloropropene (1,3-D), and chloropicrin. Variations among Biolog fingerprints showed that the effect of MeBr on heterotrophic microbial activities was most severe in the first week and that thereafter the effects of MeBr and the other fumigants were expressed at much lower levels. The results of PLFA analysis demonstrated a community shift in all treatments to a community dominated by gram-positive bacterial biomass. Different 16S rDNA profiles from fumigated soils were quantified by analyzing the DGGE band patterns. The Shannon-Weaver index of diversity, H, was calculated for each fumigated soil sample. High diversity indices were maintained between the control soil and the fumigant-treated soils, except for MeBr (H decreased from 1.14 to 0.13). After 12 weeks of incubation, H increased to 0.73 in the MeBr-treated samples. Sequence analysis of clones generated from unique bands showed the presence of taxonomically unique clones that had emerged from the MeBr-treated samples and were dominated by clones closely related to Bacillus spp. and Heliothrix oregonensis. Variations in the data were much higher in the Biolog assay than in the PLFA and DGGE assays, suggesting a high sensitivity of PLFA analysis and DGGE in monitoring the effects of fumigants on soil community composition and structure. Our results indicate that MeBr has the greatest impact on soil microbial communities and that 1,3-D has the least impact.
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Wu CH, Yang CH, Lee JN, Hsu SC, Tsai EM. Weekly and monthly regimens of paclitaxel and carboplatin in the management of advanced ovarian cancer. A preliminary report on side effects. Int J Gynecol Cancer 2001; 11:295-9. [PMID: 11520368 DOI: 10.1046/j.1525-1438.2001.011004295.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This preliminary study was carried out over 18 months to evaluate whether the side effects in patients with advanced ovarian cancer receiving chemotherapy using paclitaxel-carboplatin differed between weekly (98 cycles in 14 patients) and monthly (102 cycles in 15 patients) administrations. We used paclitaxel (60 mg/m2) and carboplatin (AUC of 2) in the weekly regimen and 175 mg/m2 of paclitaxel and carboplatin (AUC of 6) in the monthly regimen. All eligible patients received at least four cycles of treatment in both regimens. The results revealed significantly decreased hematological toxicity in weekly regimens relative to monthly ones, ie, 7.1% vs. 18.6% of anemia (> or = grade 2), 7.1% vs. 32.3% of grade 3/4 granulocytopenia, and 0% vs. 15.7% of >grade 2 thrombocytopenia. There was no significant difference in nonhematological toxicities between the two regimens. The incidence of unscheduled events was much less in the weekly regimen than in the monthly one; ie, delayed treatment (3 vs. 18 events), unanticipated hospitalizations (3 vs. 15 times), and supplemental support with G-CSF (7 vs. 33 times). Complete responses were observed in 6 of 14 patients in the weekly regimen and in five of 15 patients in the monthly regimen, while partial responses were seen in four and five patients in the weekly and monthly regimens, respectively. The present results demonstrate that the weekly regimen can achieve the benefits of tolerable toxicity with significantly reduced myelosuppression and improved cost-effectiveness in terms of unscheduled events.
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109
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Kim TD, Cho SE, Yang CH, Kim J. Analysis of Fc gammaRIII and IgG Fc polymorphism reveals functional and evolutionary implications of protein-protein interaction. J Mol Evol 2001; 53:1-9. [PMID: 11683317 DOI: 10.1007/s002390010186] [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: 10/20/2022]
Abstract
Fc gamma receptor III (Fc gammaRIII), a low-affinity receptor for the Fc portion of immunoglobulin G (IgG Fc), targets antigen-antibody complexes in a variety of effector cells of the immune system. We have investigated Fc gammaRIII and IgG Fc polymorphism and made comparative analysis of the functional and evolutionary implications of the interaction between these two molecules. Sequence analysis and comparison of the three-dimensional structure suggest that the C-terminal Ig domain of Fc gammaRIII is associated with the binding of IgG. The polymorphic residues of Fc gammaRIII are mainly located in the region of the C-terminal Ig domain that might be involved in IgG binding. Therefore, polymorphism and functional binding affinity seems to be related to each other as has been increasingly implicated in clinical observations. IgG Fcs, the natural ligand of Fc gammaRs, also exhibit significant polymorphism. Three regions have been identified where polymorphism frequently occurs: the putative FcR binding site, the linker region, and the intermolecular domain-domain interface of the second Ig domain. The putative Fc gammaR binding sites where polymorphic, and isotype-specific residues cluster are consistent with the regions that have been identified by mutagenesis and molecular modeling studies. The polymorphic residues of IgG Fc were mainly located in the molecular surface, which could be used in the recognition of other binding molecules. These observations suggest that polymorphic and isotype-specific residues in IgG Fc are closely related to their function and protein-protein interaction. Therefore, the colocalization of the polymorphic residues of Fc gammaRIII and IgG Fcs at their docking sites implies that the polymorphic residues would affect the IgG-Fc gammaRIII binding interactions to optimize their signaling through evolution.
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110
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Yang CH, Yang T. Somatic and Germline Mutation of Forensic DNA Markers. FORENSIC SCIENCE REVIEW 2001; 13:131-152. [PMID: 26256306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Somatic and germline mutations of forensic DNA markers DQA1, PM, STR, minisatellite DNA, and mtDNA are reviewed in this paper. DQA1 and PM are stable point substitution polymorphic loci in nuclear DNA (nucDNA); thus, somatic and germline mutations are rarely reported. STR loci somatic mutations are not found in normal cells but are very unstable in cancer cells. Germline mutations are detected in STR loci with a mutation rate of approximately 0.1%. Germline mutations of STR loci are nucleotide sequence, sex, and age dependent. Among the 13 CODIS core, TH01, TPOX, D16S539, and D3S1358 are more stable than others. Both somatic and germline mutations are found in minisatellite loci. Somatic mutations at mtDNA central region (CR) are detected in different tissues within the same individual, and the mutation rates are high in several cancer tissues. The intergenerational mutation rate of mtDNA CR is estimated to be 1/400 to 1/1200 per generation by phylogenetic analysis. The intergenerational mutation rate estimated by the recently developed pedigree method is higher, 14/1221 (1/87). This rate does not include the hot spot and heteroplasmic mutation. If substitution, heteroplasmic, and poly-C tract mutation are included, the mutation rate of mtDNA CR is 33/1590 (1/49) per generation. Proposals and practices on the interpretation of test data that may be associated with mutation are also discussed.
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111
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Cheng CT, Lo V, Chen J, Chen WC, Lin CY, Lin HC, Yang CH, Sheh L. Synthesis and DNA nicking studies of a novel cyclic peptide: cyclo[Lys-Trp-Lys-Ahx-]. Bioorg Med Chem 2001; 9:1493-8. [PMID: 11408167 DOI: 10.1016/s0968-0896(01)00043-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Two novel cyclic tetrapeptides: cyclo[Lys-Tyr-Lys-Ahx-] 7a and cyclo[Lys-Trp-Lys-Ahx-] 7b were synthesized by coupling protected amino acid in solution and the subsequent cyclization effected by the pentafluorophenyl ester method as described in previous papers. These cyclic peptides were designed and synthesized to study their interaction with DNA, based on previous reports that linear peptides Lys-Tyr-Lys and Lys-Trp-Lys could bind to various forms of DNA and cleaved supercoiled DNA at apurinic sites. Ethidium bromide displacement assay showed that the apparent DNA binding constant of linear Lys-Tyr-Lys and cyclic peptide 7a are far below 1 x 10(3) M(-1), whereas those of cyclic peptide 7b and linear Lys-Trp-Lys are 1.9 x 10(4) M(-1) and 9.5 x 10(3) M(-1), respectively. Kinetic studies using agarose gel electrophoresis showed that cyclic peptide 7b and Lys-Trp-Lys possessed DNA nicking activity on natural supercoiled phi X174 DNA with nicking rate of 50.7 and 75.6 pM min(-1) at 65 degrees C, respectively, whereas cyclic peptide 7a and linear Lys-Tyr-Lys were devoid of the corresponding activity. The DNA nicking rate increased significantly with increase in reaction temperature. At reaction temperatures lower than 65 degrees C, the DNA nicking rate of cyclic peptide 7b exceeded that of linear Lys-Trp-Lys. The addition of 1 microM ferrous ion did not give significant enhancement effect on the DNA nicking rate by the peptides. UV irradiation gave a marked rate enhancement on the DNA nicking rate of linear Lys-Trp-Lys and a moderate enhancement on the DNA nicking rate of cyclic peptide 7b.
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112
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Abstract
In this paper a novel algorithm for motion estimation of the endometrium in a sequence of ultrasonic images is presented. The algorithm used is based on the criterion that a pixel of a motion object at different times has a different gray value. The motion estimation includes motion frequency and thickness; the former one is determined by the detection of change of a pixel value in a sequence of images during a given time period, and the latter is the result of the object's dimension divided by its extended width. The algorithm has been tested on synthetic and real images, and the results are encouraging.
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113
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Yip HK, Wu CJ, Chang HW, Chen MC, Hang CL, Fang CY, Hsieh YK, Yang CH, Yeh KH, Fu M. Comparison of impact of primary percutaneous transluminal coronary angioplasty and primary stenting on short-term mortality in patients with cardiogenic shock and evaluation of prognostic determinants. Am J Cardiol 2001; 87:1184-8; A4. [PMID: 11356395 DOI: 10.1016/s0002-9149(01)01491-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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114
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Chou ML, Haung MD, Yang CH. EMF genes interact with late-flowering genes in regulating floral initiation genes during shoot development in Arabidopsis thaliana. PLANT & CELL PHYSIOLOGY 2001; 42:499-507. [PMID: 11382816 DOI: 10.1093/pcp/pce062] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
To investigate the mechanisms regulating the initiation of floral development in Arabidopsis, a construct containing beta-glucuronidase (GUS) gene driven by APETALA1 promoter (AP1::GUS) was introduced into emf fwa and emf ft double mutants. GUS activity was strongly detected on shoot meristem of emf1-1 single mutants harboring AP1::GUS construct just 5 d after germination. By contrast, GUS activity was undetectable on emf1-1 fwa-1, emf1-1 ft-1, emf2-1 fwa-1, emf2-3 fwa-1 and emf2-3 ft-1 double mutants harboring AP1::GUS construct 10 d after germination. GUS activity was only weakly detected on the apical meristem of 20-day-old emf1-1 fwa-1 and emf2-1 fwa-1 seedlings. During this time, only sessile leaves were produced. Further analysis indicated that AP1 was strongly expressed in 10-day-old emf1-1 and emf2-1 single mutants. Its expression was significantly reduced in all emf1-1 or emf2-1 late-flowering double mutants tested. Similar to AP1, the expression of LEAFY (LFY) was also high in emf1-1 and emf2-1 single mutants and reduced in emf1-1 or emf2-1 late-flowering double mutants. Our results indicate that the precocious expression of AP1 and LFY is dependent not only on the low EMF and FWA activities but also on the expression of most of the late-flowering genes such as FT, FCA, FE, CO and GI. These data also reveal that most late-flowering genes may function downstream of EMF or in pathways distinct from EMF to activate genes specified floral meristem identity during shoot maturation in Arabidopsis.
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115
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Yang CH, Murti A, Pfeffer SR, Kim JG, Donner DB, Pfeffer LM. Interferon alpha /beta promotes cell survival by activating nuclear factor kappa B through phosphatidylinositol 3-kinase and Akt. J Biol Chem 2001; 276:13756-61. [PMID: 11278812 DOI: 10.1074/jbc.m011006200] [Citation(s) in RCA: 169] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Interferons (IFNs) play critical roles in host defense by modulating gene expression via activation of signal transducer and activator of transcription (STAT) factors. IFN-alpha/beta also activates another transcription factor, nuclear factor kappaB (NF-kappaB), which protects cells against apoptotic stimuli. NF-kappaB activation requires the IFN-dependent association of STAT3 with the IFNAR1 chain of the IFN receptor. IFN-dependent NF-kappaB activation involves the sequential activation of a serine kinase cascade involving phosphatidylinositol 3-kinase (PI-3K) and Akt. Whereas constitutively active PI-3K and Akt induce NF-kappaB activation, Ly294002 (a PI-3K inhibitor), dominant-negative PI-3K, and kinase-dead Akt block IFN-dependent NF-kappaB activation. Moreover, dominant-negative PI-3K blocks IFN-promoted degradation of kappaBox alpha. Ly294002, a dominant-negative PI-3K construct, and kinase-dead Akt block IFN-promoted cell survival, enhancing apoptotic cell death. Therefore, STAT3, PI-3K, and Akt are components of an IFN signaling pathway that promotes cell survival through NF-kappaB activation.
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116
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Abstract
PURPOSE Ganciclovir (GCV) implants are highly effective in delaying the progression of cytomegalovirus (CMV) retinitis. Rhegmatogenous retinal detachments can occur in untreated eyes with CMV retinitis or in eyes treated with anti-CMV therapy, which may include placement of a GCV implant. The clinical management of CMV retinitis and associated retinal detachment often involves the concurrent use of silicone oil and GCV implants. The authors investigated the effect of silicone oil tamponade on intravitreal drug levels achieved with the GCV implant. METHODS The authors performed gas compression vitrectomy in the right eyes of 29 New Zealand white rabbits. They then inserted a 5-mg GCV implant into the vitreous cavity through an inferotemporal sclerotomy. Saline (1 cc), silicone oil 0.5 cc, or silicone oil 1.0 cc was then injected into the midvitreous cavity of 9, 8, and 12 rabbits, respectively. On postoperative days 21, 42, and 70, the rabbits were killed and the right eyes were immediately collected and stored at -70 degrees C until all samples were obtained. Vitreous was then isolated and drug levels were determined by high-pressure liquid chromatography. RESULTS Vitreous GCV levels at days 21 and 42 were similar in both the saline-filled and silicone oil-filled eyes. At day 70, GCV levels in both the saline- and silicone-filled eyes were statistically significantly lower than at day 21 (P < 0.05 for all groups). In addition, at day 70, GCV levels in the saline-filled eyes were significantly lower than in silicone-filled eyes (saline versus 0.5 cc oil, P = 0.01; saline versus 1 cc oil, P = 0.09). CONCLUSIONS Effective GCV levels are maintained in the aqueous phase of the vitreous cavity of eyes with silicone oil tamponade. Ganciclovir levels may be maintained longer in eyes with silicone oil tamponade than in those without. These results support the use of combined GCV implants and silicone oil tamponade in patients with CMV retinitis and associated retinal detachment.
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117
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Yang CH, Chung PC, Yang CH. Hand motion assessment and rehabilitation system. Biomed Mater Eng 2001; 10:131-9. [PMID: 11202143] [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]
Abstract
Along with the rapid development of information technology, computers play an increasingly prominent and important role. One current trend is to use computers as instruments for physical rehabilitation. In this study, we introduce a new hand motion assessment and rehabilitation system. This system assesses a user's grip strength and records the sudden changes in air pressure through a circuit and A/D adapter. A PC interface transforms and saves the data in a data record file. The data is then compiled and combined with a patient's case history and keyed into a database as reference for clinical use. The system is highly efficient, cheap and convenient to use. Doctors can use it to monitor and analyze the progress of a rehabilitation program.
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Kong LR, Tzeng DD, Yang CH. Generation of PCR-based DNA fragments for specific detection of Streptomyces saraceticus N45. PROCEEDINGS OF THE NATIONAL SCIENCE COUNCIL, REPUBLIC OF CHINA. PART B, LIFE SCIENCES 2001; 25:119-27. [PMID: 11370759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Streptomyces saraceticus strain N45, a saprophytic Gram-positive bacteria, has been shown to harbor high chitinase activity. Due to its potential use in biological control, the cloning of chitinase genes and the development of methods to quickly and precisely detect its presence have become necessary. In this study, PCR-based random amplified polymorphic DNA (RAPD) and PCR strategies were used to amplify random DNA fragments from the genome of S. saraceticus N45. Three amplified DNA fragments, 417, 523 and 655 bp in length, were further isolated, subcloned and sequenced. Nest primers were designed from terminal ends of these three fragments and used for further PCR reactions. A single specific band was produced from the genomic DNA of S. saraceticus N45 for each nest primer pair. These three single bands were S. saraceticus N45 specific and were not amplified from other species of Streptomyces or bacteria, such as Ralstonia solanacearum, Agrobacterium tumefaciens, E. coli, Bacillus subtilis and Xanthomonas campestris pv. campestris. Through detection of the coexistence of these three fragments in PCR reaction using DNA or bacterial cells directly, the presence of S. saraceticus N45 can be confirmed. Further Southern analysis indicated that these three DNA fragments were specifically present in the S. saraceticus N45 genome in a single copy manner, and therefore, that they can potentially be used as markers for identification of S. saraceticus N45.
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119
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Yang CH, Crowley DE, Borneman J, Keen NT. Microbial phyllosphere populations are more complex than previously realized. Proc Natl Acad Sci U S A 2001; 98:3889-94. [PMID: 11274410 PMCID: PMC31148 DOI: 10.1073/pnas.051633898] [Citation(s) in RCA: 191] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/29/2000] [Indexed: 11/18/2022] Open
Abstract
Phyllosphere microbial communities were evaluated on leaves of field-grown plant species by culture-dependent and -independent methods. Denaturing gradient gel electrophoresis (DGGE) with 16S rDNA primers generally indicated that microbial community structures were similar on different individuals of the same plant species, but unique on different plant species. Phyllosphere bacteria were identified from Citrus sinesis (cv. Valencia) by using DGGE analysis followed by cloning and sequencing of the dominant rDNA bands. Of the 17 unique sequences obtained, database queries showed only four strains that had been described previously as phyllosphere bacteria. Five of the 17 sequences had 16S similarities lower than 90% to database entries, suggesting that they represent previously undescribed species. In addition, three fungal species were also identified. Very different 16S rDNA DGGE banding profiles were obtained when replicate cv. Valencia leaf samples were cultured in BIOLOG EcoPlates for 4.5 days. All of these rDNA sequences had 97--100% similarity to those of known phyllosphere bacteria, but only two of them matched those identified by the culture independent DGGE analysis. Like other studied ecosystems, microbial phyllosphere communities therefore are more complex than previously thought, based on conventional culture-based methods.
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120
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Yang CH, Hwang JP, Tsai SJ, Liu CM. The clinical applications of Mini-Mental State Examination in geropsychiatric inpatients. Int J Psychiatry Med 2001; 30:277-85. [PMID: 11209994 DOI: 10.2190/fun0-jkq0-kl56-vc84] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE This study investigated the association between Mini-Mental State Examination (MMSE) scores and diagnosis, computerized tomographic scans or electroencephalogram findings in geropsychiatric inpatients (age > or = 65). METHOD We analyzed the MMSE records of patients sixty-five and older who had been hospitalized in our psychiatric ward during a nine-year period. Case data were collected by review of chart records. RESULTS In these patients, MMSE scores were significantly different among the seven diagnostic groups included. Demented patients had the lowest MMSE scores. Patients who had abnormal findings on computerized tomographic scans or electroencephalogram had lower MMSE than patients with normal findings. CONCLUSION Our findings suggest that the MMSE is a useful screening instrument for organicity in the geropsychiatric inpatients. However, because of the lower average MMSE score in geropsychiatric inpatients, the optimal cut-offpoint of MMSE for dementia should be lower than those used in other populations.
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Abstract
OBJECTIVE Both repetitive talk and behaviors (repetitive phenomena) are common in demented patients and are bothersome to their caregivers and families. The purpose of this preliminary report was to explore these repetitive phenomena in demented patients admitted to a geropsychiatric ward. METHOD The sample population consisted of 141 demented patients. Patients' caregivers were asked if patients had presented a repetitive fixed pattern of physical action or talk since the onset of dementia. RESULTS Of the 141 demented patients included in the study, seventy-nine had repetitive phenomena. Patients with these phenomena had various presentations and developed them in the early stage of dementia. CONCLUSIONS Repetitive phenomena are widespread in dementia, especially for older patients, and may be an early sign of dementia. The characteristics of repetitive phenomena and some likely underlying mechanisms are discussed.
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Lee YC, Chen YS, Yang CH, Tsai SJ. The correlations between the difficult temperament and subjective psychiatric symptoms in Chinese early adolescents. Child Psychiatry Hum Dev 2001; 31:129-37. [PMID: 11089301 DOI: 10.1023/a:1001996526248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This study was designed to assess the intercorrelations between difficult temperament factors and self-rating psychiatric symptoms in Chinese early adolescents. The study subjects completed the Chinese Adolescent Temperament Self-Rating Questionnaire and Brief Psychiatric Symptom Rating Scale. Results revealed that the group of subjects with two or more difficult temperament factors showed significantly higher scores in some of self-rating psychiatric symptoms. In addition to difficult temperament factors, low score of task orientation and tactile threshold also appeared to be risk factors for self perceived psychiatric symptoms in the Chinese adolescents.
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Perkins SL, Gallemore RP, Yang CH, Guo H, Ashton P, Jaffe GJ. Pharmacokinetics of the fluocinolone/5-fluorouracil codrug in the gas-filled eye. Retina 2001; 20:514-9. [PMID: 11039427 DOI: 10.1097/00006982-200009000-00013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To determine the effect of intraocular gas tamponade on drug levels achieved with the intravitreal sustained-release fluocinolone (FL)/5-fluorouracil (5-FU) codrug pellet. METHODS After insertion of a 10-mg codrug pellet into the right eyes of 43 New Zealand white rabbits, perfluoropropane (0.4 mL of 100% C3F8) or a control sham was then injected into the midvitreous cavity. On postoperative days 2, 4, 7, 21, and 42, aqueous samples were collected, the rabbits were killed, and the right eyes were enucleated. The vitreous and remaining codrug pellet were then isolated. Pellet and intravitreal drug levels were determined by high-pressure liquid chromatography. RESULTS No measurable drug levels were detected in any of the aqueous samples. Maximal gas expansion occurred by day 4 and partial resorption was observed by days 14 to 21. Vitreous FL and 5-FU levels during C3F8 expansion (day 2) were statistically significantly higher in the gas-filled eyes. On postoperative days 4, 7, 21, and 42, there were no statistically significant differences between FL and 5-FU drug levels in eyes containing C3F8 as compared with control eyes. Pellet codrug, FL, and 5-FU levels over time were similar in gas-filled and control eyes. CONCLUSIONS Intraocular gas tamponade does not significantly affect the sustained intravitreal drug levels achieved with the FL/5-FU codrug. If clinically efficacious, the FL/5-FU codrug formulation does not need to be altered to treat proliferative vitreoretinopathy in the presence of intraocular gas.
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Yeung L, Hung PT, Lin LL, Yang CH, Chiou GC. Effects of dopamine antagonists in human eye accommodation. J Ocul Pharmacol Ther 2001; 17:11-7. [PMID: 11322633 DOI: 10.1089/108076801750125595] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The purpose of this study was to evaluate the effects of dopamine antagonists in accommodation of the human eye. The dopamine antagonist drugs used in this experiment include 0.5% metoclopramide and 0.25% droperidol. Eighteen healthy subjects were enrolled; they were randomly assigned, in double-masked fashion, to receive topical administration of a single drop of either 0.5% metoclopramide or 0.25% droperidol in one eye, with the fellow eye receiving isotonic saline as control. The accommodative abilities of both eyes were measured before instillation, and also at 3 and 6 hr after instillation of drugs, respectively. We studied the latency of reaction, the rate of accommodation, the average accommodative power, the rate of recovering and the total recovering time as the five parameters for evaluating the accommodative ability of each eye. The results showed that there were significant changes in two parameters: the rate of accommodation and rate of recovering, whereas there were no significant changes in the other three parameters: latency of accommodation, average power of accommodation and total recovering time. In conclusion, the dopamine antagonists may have some effects on the rate of accommodation but not the degree of accommodation. Further studies with higher concentrations of these dopamine antagonists on dose-response relationships are needed before exact drug efficacy can be drawn.
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Kwon H, Park S, Lee S, Lee DK, Yang CH. Determination of binding constant of transcription factor AP-1 and DNA. Application of inhibitors. EUROPEAN JOURNAL OF BIOCHEMISTRY 2001; 268:565-72. [PMID: 11168395 DOI: 10.1046/j.1432-1327.2001.01897.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The equilibrium binding and association kinetics of the fos-jun dimer (basic and leucine zipper domain) to the AP-1 DNA were studied using a quantitative assay. The basic-region and leucine zipper (bZip) domain of c-fos was expressed as a fusion protein with glutathione S-transferase, and it was bound to glutathione-agarose. The GST-fused fos bZip region was allowed to form a heterodimer with the bZip domain of c-jun, to which radiolabeled AP-1 nucleotides were added. After thorough washing, the gel-bound radioactivity was counted. The binding and dissociation rate constants (k(1) and k-(1)) of the fos-jun dimer and DNA could be obtained from a time-course experiment. The association binding constant (K(1)) was determined using both a thermodynamic equation and kinetic parameters. Nordihydroguaiaretic acid (NDGA), momordin I, natural product inhibitors of the fos-jun/DNA complex formation, was applied to this jun-GST-fused fos system and it was found to decrease the apparent equilibrium binding of dimer and DNA. The thermodynamic constant of dimer and inhibitor binding was also determined.
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