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Huang CC, Shih MJ, Tsai YH, Chang YC, Tsao TC, Hsu KH. Effects of inverse ratio ventilation versus positive end-expiratory pressure on gas exchange and gastric intramucosal PCO(2) and pH under constant mean airway pressure in acute respiratory distress syndrome. Anesthesiology 2001; 95:1182-8. [PMID: 11684988 DOI: 10.1097/00000542-200111000-00023] [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: 11/25/2022]
Abstract
BACKGROUND In patients with acute respiratory distress syndrome, whether inverse ratio ventilation differs from high positive end-expiratory pressure (PEEP) for gas exchange under a similar mean airway pressure has not been adequately examined. The authors used arterial oxygenation, gastric intramucosal partial pressure of carbon dioxide (PiCO(2)), and pH (pHi) to assess whether pressure-controlled inverse ratio ventilation (PC-IRV) offers more benefits than pressure-controlled ventilation (PCV) with PEEP. METHODS Seventeen acute respiratory distress syndrome patients were enrolled and underwent mechanical ventilation with a PCV inspiratory-to-expiratory ratio of 1:2, followed by PC-IRV 1:1 initially. Then, they were randomly assigned to receive PC-IRV 2:1, then 4:1 or 4:1, and then 2:1, alternately. The baseline setting of PCV 1:2 was repeated between the settings of PC-IRV 2:1 and 4:1. Mean airway pressure and tidal volume were kept constant by adjusting the levels of peak inspiratory pressure and applied PEEP. In each ventilatory mode, hemodynamics, pulmonary mechanics, arterial and mixed venous blood gas analysis, PiCO(2), and pHi were measured after a 1-h period of stabilization. RESULTS With a constant mean airway pressure, PC-IRV 2:1 and 4:1 decreased arterial and mixed venous oxygenation as compared with baseline PCV 1:2. Neither the global oxygenation indices with oxygen delivery and uptake nor PiCO(2) and pHi were improved by PC-IRV. During PC-IRV, applied PEEP was lower, and auto-PEEP was higher. CONCLUSION When substituting inverse ratio ventilation for applied PEEP to keep mean airway pressure constant, PC-IRV does not contribute more to better gas exchange and gastric intramucosal PiCO(2) and pHi than does PCV 1:2 for acute respiratory distress syndrome patients, regardless of the inspiratory-to-expiratory ratios.
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Lee IH, Soong BW, Lu YC, Chang YC. Dentatorubropallidoluysian atrophy in Chinese. ARCHIVES OF NEUROLOGY 2001; 58:1905-8. [PMID: 11709002 DOI: 10.1001/archneur.58.11.1905] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Dentatorubropallidoluysian atrophy (DRPLA) is a rare, autosomal dominant neurodegenerative disease characterized by a range of clinical manifestations, including cerebellar ataxia, epilepsy, myoclonus, choreoathetosis, and dementia. Outside the Japanese population, the prevalence is extremely low worldwide. The reason for different ethnic prevalences of DRPLA is unclear. A previous assumption was that large normal alleles contribute to generation of expanded alleles and the relative frequencies of DRPLA. OBJECTIVES To describe the clinical, radiological, and genetic features of the first reported Chinese family with DRPLA, to our knowledge, and to compare the size distribution of normal alleles at the DRPLA locus in healthy Chinese individuals with that of other ethnic groups. PATIENTS AND METHODS Of 80 Chinese kindreds with autosomally dominant spinocerebellar ataxias, 1 pedigree with 2 affected patients was found by polymerase chain reaction to carry the characteristic DRPLA mutation. The allele frequencies of different CAG repeat lengths at the DRPLA locus in 225 healthy Chinese individuals were also analyzed and compared with Japanese, white, and African American distributions. RESULTS The clinical presentations of the 2 Chinese patients affected with DRPLA are similar to those described in Japanese patients, except that the affected father exhibited myoclonus but not chorea. Although the normal DRPLA allele size is distributed similarly in Chinese and Japanese populations, DRPLA in Chinese individuals is rare. Thus far, to our knowledge, only 1 intermediate-sized allele containing more than 30 CAG repeats has been reported among healthy Chinese individuals, in contrast to 3 among Japanese populations. CONCLUSION The ethnic prevalence of DRPLA seems to be correlated with the prevalence of intermediate-sized alleles in individual populations.
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Chang YC, Yang SF, Hsieh YS. Regulation of matrix metalloproteinase-2 production by cytokines and pharmacological agents in human pulp cell cultures. J Endod 2001; 27:679-82. [PMID: 11716080 DOI: 10.1097/00004770-200111000-00007] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Type IV matrix metalloproteinases (MMPs) are members of the family of MMPs and are thought to play an important role in degradation of extracellular components. Human pulp cells can secrete and produce these enzymes. Recent evidence shows that MMPs may play a role in pulpal inflammation. To date little is known regarding the regulation of MMPs in human pulp cell cultures. The purpose of this study was to determine the effects of cytokines (interleukin-1 and transforming growth factor-beta (TGF-beta), protein synthesis inhibitor cycloheximide (CD), and protein kinase C inhibitors (H7 and Go6976) on the secretion and production of MMPs by human pulp cell cultures using gelatin zymography. The main gelatinase secreted by human pulp cells migrated at 72 kDa and represented MMP-2. Minor gelatinolytic bands were also observed at 92 kDa regions that correspond to MMP-9. After an 8-day culture period TGF-beta, CD, H7, and Go6976 were found to depress MMP-2 production. The inhibition decreased in an order of CD > H7 > TGF-beta > Go6976. IL-1 was found to elevate MMP-2 production. Human pulp cells, however treated with either cytokines or pharmacological agents had no effect on the pattern of MMP-9 produced or secreted in either cell extracts or conditioned medium fractions. These observations suggest that the cytokines and pharmacological agents can regulate MMP-2 produced by human pulp cells. Inflammatory cytokines stimulate the production of elevated levels of MMP-2 and MMP-2 might play a role in pulpal inflammation. In addition agents that target protein synthesis or the protein kinase C pathway in human pulp cells inhibit MMP-2 production, and such inhibition may contribute to the pathogenesis of pulpal inflammation. Such inhibition might contribute to therapeutic efficacy.
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Hsu MM, Chou YY, Chang YC, Chou TC, Wong CS. An analysis of excitatory amino acids, nitric oxide, and prostaglandin E2 in the cerebrospinal fluid of pregnant women: the effect on labor pain. Anesth Analg 2001; 93:1293-6. [PMID: 11682417 DOI: 10.1097/00000539-200111000-00053] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
UNLABELLED It is still unclear which neurotransmitters are involved in labor pain. We measured the concentrations of excitatory amino acids, nitric oxide, and prostaglandin E2 in the cerebrospinal fluid (CSF) of pregnant women, particularly in those with labor pain. The patients included in the study consisted of women who underwent cesarean delivery either with labor pain (Labor Pain group, n = 40) or without labor pain (Nonlabor Pain group, n = 58). All patients received spinal anesthesia (intrathecal injection of 10-12 mg of bupivacaine) for the operation, and 2 mL of CSF was collected before bupivacaine injection. Concentrations of aspartate and glutamate (0.50 +/- 0.06 microM and 0.79 +/- 0.10 microM, respectively) were significantly larger in the Labor Pain group than in the Nonlabor Pain group (0.35 +/- 0.03 microM and 0.54 +/- 0.04 microM, P < 0.05). There were no significant differences in the concentrations of nitric oxide and prostaglandin E2 between the groups. A positive correlation was found between CSF concentrations of excitatory amino acids and labor pain. IMPLICATIONS The excitatory amino acids, aspartate and glutamate, play a role in labor pain. N-methyl-D-aspartate receptor antagonists may be useful for labor pain and postlabor uterine contraction pain relief.
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Hong FE, Tsai YT, Chang YC, Ko BT. Linking two alkyne-bridged dicobalt complexes via a urea-based ligand: synthesis and spectroscopic and structural characterization of [[Co(2)(CO)(6)(mu-HC identical with C-)]-CH(2)NH](2)C=O. Inorg Chem 2001; 40:5487-8. [PMID: 11599944 DOI: 10.1021/ic010071e] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Lin GR, Chang YC. Equivalent-Time Electro-Optic Sampling by use of a Picosecond Laser with a Voltage-Controlled Optoelectronic Pulse-Delay Tuning Circuit. APPLIED OPTICS 2001; 40:5530-5538. [PMID: 18364840 DOI: 10.1364/ao.40.005530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We demonstrate a delay-line-free electro-optic sampling (EOS) system by using a novel ultrafast laser with a voltage-controlled pulse-delay tuning circuit (PDTC). The digital PDTC was designed as a substitute for a conventional optomechanical delay line in the EOS system, which facilitates the theoretical phase-tuning range of 4pi. The maximum delay time, tuning gain, and resolution of the PDTC are 3.6 ns (1.8 periods), 0.54 ns/V, and 0.2 ps, respectively. Arbitrary waveforms generated from microwave synthesizers, electrical pulse generators, and frequency prescalars are successfully sampled by use of this system, with a less than 8% deviation in the results.
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Chang YC, Huang FM, Tai KW, Chou MY. The effect of sodium hypochlorite and chlorhexidine on cultured human periodontal ligament cells. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 2001; 92:446-50. [PMID: 11598582 DOI: 10.1067/moe.2001.116812] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The objective of this study was to examine the effects of sodium hypochlorite (NaOCl) and chlorhexidine (CHx) on cultured human periodontal ligament (PDL) cells in vitro. STUDY DESIGN The effects of irrigation solutions on human PDL cells were evaluated by propidium iodide fluorescence cytotoxicity assay, protein synthesis assay, and mitochondrial activity. RESULTS Both NaOCl and CHx were cytotoxic to human PDL cells in a concentration- and contact time-dependent manner. In addition, CHx inhibited protein synthesis in human PDL cells. Although NaOCl displayed cellular cytotoxicity, it showed no protein inhibition in the PDL cells. Furthermore, both NaOCl and CHx exhibited an inhibitory effect on mitochondrial activity on human PDL cells. CONCLUSIONS This study suggests that these irrigation fluids may cause detrimental effects on vital tissues. Its clinical significance, however, needs to be evaluated further because concentration used, exposure time to the agent, and exposure surface area are important factors affecting the resulting effect.
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Tung IC, Wu WC, Kao YH, Chang YC, Chung CH, Hu DN. The effect of combined 5-fluorouracil and dexamethasone on cultured human retinal pigment epithelial cells. Kaohsiung J Med Sci 2001; 17:524-9. [PMID: 11831116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
This study was designed to investigate the inhibitory effect of 5-fluorouracil (5-FU) and dexamethasone (DEX) on the proliferation of human retinal pigment epithelial (RPE) cells in vitro. The human RPE cells (R-50 cell line) were cultured and exposed to various concentrations of combined 5-FU (0, 250, 500, 1000, 2000 ng/ml) and DEX (0, 1, 10, 100, 200 micrograms/ml). The cells were incubated for 96 hr and the medium was changed every 48 hr to replenish the drug action. Cell viability was assessed using cell counting and trypan blue exclusion method. Tetrazolium salt, which can be metabolized by mitochondrial dehydrogenase to form a formazan dye, was used to assay cell proliferation. Treatment with 5-FU alone inhibited cell proliferation in a dose-dependent manner. The concentration of 5-FU that inhibited growth by 50% (IC50) was found to be 704.12 ng/ml. There was a bimodal effect of DEX on RPE cells--stimulation at low concentrations (1, 10 micrograms/ml) and inhibition at high concentrations (100, 200 micrograms/ml). When the two drugs were combined, there was additive inhibition in the concentration of 200 micrograms/ml of DEX. These results indicate that a combination of 5-FU and DEX is no more effective in the inhibition of human RPE cells, except in combination with high concentrations of DEX (> or = 200 micrograms/ml).
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Lane HY, Jann MW, Chang YC, Chiu CC, Huang MC, Lee SH, Chang WH. Repeated ingestion of grapefruit juice does not alter clozapine's steady-state plasma levels, effectiveness, and tolerability. J Clin Psychiatry 2001; 62:812-7. [PMID: 11816871 DOI: 10.4088/jcp.v62n1010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Grapefruit juice can inhibit the gastrointestinal activity of cytochrome P450 (CYP) 3A4, while its effect on CYP1A2 remains controversial. Several grapefruit juice bioflavonoids also modulate the activity of the drug transporter P-glycoprotein in the gut and in the blood-brain barrier. Both CYP1A2 and CYP3A4 are involved in clozapine metabolism. This study investigated the effects of repeated ingestion of grapefruit juice on multiple-dose pharmacokinetics and pharmacodynamics of clozapine in schizophrenic patients. METHOD Clozapine therapy was initiated for fifteen treatment-resistant schizophrenic inpatients (DSM-IV criteria). The doses were individually titrated from day -35 to day -15 and then kept unchanged from day -14 to day 49. Regular-strength grapefruit juice (250 mL) was coadministered b.i.d. with each clozapine dose from day 15 to day 28. Plasma levels of clozapine and its main metabolites (norclozapine and clozapine N-oxide) were obtained, and clinical efficacy and safety assessments were completed prior to juice administration (days 0, 7, and 14), during the coadministration (days 17, 21, and 28), and after cessation of the juice (days 35, 42, and 49). RESULTS After reaching steady states, plasma concentrations of clozapine and its metabolites and Positive and Negative Syndrome Scale scores were not significantly altered by the effect of grapefruit juice ingestion. The Clinical Global Impressions scale scores, Calgary Depression Scale scores, and side effect profiles (by the Extrapyramidal Symptom Rating Scale, the UKU Side Effect Rating Scale, and thorough examinations including electrocardiography and electroencephalography) also remained constant during the study. CONCLUSION Consumption of regular-strength grapefruit juice, 250 mL b.i.d., for 14 days did not significantly impact clozapine metabolism, clinical efficacy, or tolerability. One reason is that enzymes other than CYP3A4 also mediate clozapine disposition. Also, grapefruit juice inhibits CYP3A4 in the gut, but not in the liver. The preliminary results also suggest that clozapine is unlikely to be a P-glycoprotein substrate. Further rigorous studies are necessary to reconfirm these findings.
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Chen RC, Tsai SY, Chang YC, Liou HH. Seizure frequency affects event-related potentials (P300) in epilepsy. J Clin Neurosci 2001; 8:442-6. [PMID: 11535014 DOI: 10.1054/jocn.2000.0908] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
To analyse the effect of epilepsy an P300 event-related potentials we studied 27 patients with idiopathic generalized epilepsy (IGE), 13 patients with temporal lobe epilepsy (TLE) and 60 normal controls. The prolongation of P300 latencies was highly cor related with increasing age in controls but not epileptic patients. The age-corrected P300 latency used in this study was actual P300 latency-predicted P300 latency (predicted P300 (msec)=306.20+0.79 age, P=0.001, R2=0.32). By using ANOVA analysis, the age-corrected latencies of P300 were significantly longer in TLE patients (19.72+/-47.82 msec, mean+/-SD) than in IGE patients (10.97+/-36.97 msec) and controls (0.23+/-20.28 msec). Likewise, significantly prolonged P300 latencies were seen in the epileptic patients with a seizure frequency more than 400 times (37.21+/-47.50 msec). The multivariate-adjusted odds ratio for those who had TLE was 10.97 (95% CI=3.99 - 30.14 ) in the prolonged latencies of P300 compared with that of IGE patients. The odds ratio of longer latencies of P300 was 7.43 (95% CI=2.75 - 20.08) among those who had a high seizure frequency (> or =400 times) compared with those who had a low seizure frequency. No interaction between TLE and high frequency of attacks was found. The age at onset of seizure and duration of illness was not associated with P300 latency prolongation. From the above results, we might infer that the seizure type of TLE and a high frequency of seizure are two major independent precipitate factors for abnormal latencies of P300 in the epileptic patients.
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Chang YC, Hu CC, Tseng TH, Tai KW, Lii CK, Chou MY. Synergistic effects of nicotine on arecoline-induced cytotoxicity in human buccal mucosal fibroblasts. J Oral Pathol Med 2001; 30:458-64. [PMID: 11545236 DOI: 10.1034/j.1600-0714.2001.030008458.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Areca quid chewing has been linked to oral submucous fibrosis and oral cancer. Arecoline, a major areca nut alkaloid, is considered to be the most important etiologic factor in the areca nut. In order to elucidate the pathobiological effects of arecoline, cytotoxicity assays, cellular glutathione S-transferase (GST) activity and lipid peroxidation assay were employed to investigate cultured human buccal mucosal fibroblasts. To date, there is a large proportion of areca quid chewers who are also smokers. Furthermore, nicotine, the major product of cigarette smoking, was added to test how it modulated the cytotoxicity of arecoline. At a concentration higher than 50 microg/ml, arecoline was shown to be cytotoxic to human buccal fibroblasts in a dose-dependent manner by the alamar blue dye colorimetric assay (P<0.05). In addition, arecoline significantly decreased GST activity in a dose-dependent manner (P<0.05). At concentrations of 100 microg/ml and 400 microg/ml, arecoline reduced GST activity about 21% and 46%, respectively, during a 24 h incubation period. However, arecoline at any test dose did not increase lipid peroxidation in the present human buccal fibroblast test system. The addition of extracellular nicotine acted synergistically on the arecoline-induced cytotoxicity. Arecoline at a concentration of 50 microg/ml caused about 30% of cell death over the 24 h incubation period. However, 2.5 mM nicotine enhanced the cytotoxic response and caused about 50% of cell death on 50 microg/ml arecoline-induced cytotoxicity. Taken together, arecoline may render human buccal mucosal fibroblasts more vulnerable to other reactive agents in cigarettes via GST reduction. The compounds of tobacco products may act synergistically in the pathogenesis of oral mucosal lesions in areca quid chewers. The data presented here may partly explain why patients who combined the habits of areca quid chewing and cigarette smoking are at greater risk of contracting oral cancer.
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Tai KW, Huang FM, Chang YC. Cytotoxic evaluation of root canal filling materials on primary human oral fibroblast cultures and a permanent hamster cell line. J Endod 2001; 27:571-3. [PMID: 11556560 DOI: 10.1097/00004770-200109000-00004] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To date there has been very little data on the cytotoxic response of different cell lines to root canal sealers. The objective of this study was to determine the cytocompatibility of three different extracts of root canal sealers and to compare the cytotoxic response of these materials on two different primary human oral fibroblasts (derived from gingiva and buccal mucosa) and one permanent hamster cell line (V79 cells). Cytotoxicity was judged using an assay of tetrazolium bromide reduction. The results showed that root canal sealers (AH plus, Canals, and N2) were cytotoxic to primary human oral fibroblast cultures and V79 cells. It was found that N2 was the most toxic root canal sealer among those tested in all cultures. The toxicity decreased in an order of N2 > AH plus approximately = Canals. The sensitivity of toxicity depended on the materials tested and the cell culture system used.
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Abstract
BACKGROUND A stainless-sheathed, straight needle with a hook near the top of the inner needle was designed to facilitate hepatic resections. METHODS First, using this needle, two rows of interlocking mattress sutures were made along the division line; then, hepatic transection was performed between these rows by electrocautery or forceps. RESULTS Since 1997, we have performed this kind of hepatic resections in 43 cases, including 9 right lobectomies, 5 bisegmentectomies, 7 segmentectomies, 4 subsegmentectomies, 2 partial hepatectomies, 15 left lateral segmentectomies, and 1 hepatorrhaphy. In most cases, intraoperative hemorrhage was minimal. Neither specified inflow nor backflow control procedures were needed. CONCLUSION Use of this needle may reduce the difficulty of the technique and blood loss for right hepatic lobectomy, left lateral segmentectomy, and some segmental or partial hepatectomy procedures.
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Huang FM, Tai KW, Hu CC, Chang YC. Cytotoxic effects of denture base materials on a permanent human oral epithelial cell line and on primary human oral fibroblasts in vitro. INT J PROSTHODONT 2001; 14:439-43. [PMID: 12066639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
PURPOSE The objective of this study was to determine the cytocompatibility of three different extracts of denture base resins and to compare the cytotoxic effect of these materials on a human oral epithelial KB cell line and primary human oral fibroblasts derived from buccal mucosa. MATERIALS AND METHODS Set specimens from a heat-cured resin, a self-cured resin, and a light-cured resin were eluted with culture medium for 1, 3, and 5 days. Cytotoxicity was judged using tetrazolium bromide reduction assay. RESULTS The eluates from self-cured, heat-cured, and light-cured denture base resins were cytotoxic to primary human buccal fibroblast cultures and KB cells. Self-cured resin was the most toxic denture base material among the chemicals tested in all cultures. The cytotoxicity decreased in the order of self-cured resin > heat-cured resin > light-cured resin for KB cells. The rank for buccal fibroblast cells was self-cured resin > heat-cured resin > light-cured resin. CONCLUSION The influence of the cytotoxicity depended on the materials tested and the cell culture system used. The use of both permanent and primary cells is recommended for a better screening of the cytotoxic effects of denture base resins.
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Yao WJ, Chang TT, Wang ST, Chow NH, Lin PW, Chang YC, Tu DG, Chiu NT. Clinicopathologic correlation of serum tissue polypeptide specific antigen in hepatocellular carcinoma. Oncology 2001; 61:64-70. [PMID: 11474251 DOI: 10.1159/000055355] [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: 11/19/2022]
Abstract
OBJECTIVE Recently, tissue polypeptide specific antigen (TPS) has been introduced as a cell proliferation marker. Little is known about its clinical significance in hepatocellular carcinoma (HCC). This study aimed to clarify serum TPS levels and tumor invasiveness of HCC. METHODS Serum TPS levels were determined with a monoclonal TPS IRMA assay in 69 patients with HCC. A correlation between serum TPS levels and clinical, biochemical, and pathological features was sought and compared with that of alpha-fetoprotein (AFP). In 57 healthy subjects, 56 patients with biopsy-proven chronic hepatitis and in 49 patients with liver cirrhosis, serum TPS levels were assayed and compared. RESULTS Serum TPS levels were significantly correlated with glutamic oxalacetic transaminase (p < 0.0001), glutamic pyruvic transaminase (p < 0.001), and lactate dehydrogenase (p = 0.027). There tended to be a positive relationship between serum TPS levels and tumor size, histological differentiation, capsular invasion, portal invasion, and clinical staging, although it did not reach statistical significance. A significant correlation, however, was observed between AFP and tumor size (p = 0.01), number (p = 0.042), histological grading (p = 0.028), portal invasion (p = 0.009), and clinical staging (p = 0.03). Patients with HCC had significantly higher TPS than healthy subjects (p < 0.001). However, there was substantial overlap between patients with HCC, chronic hepatitis, and liver cirrhosis. CONCLUSIONS Our data suggest that serum TPS is not significantly related to tumor invasiveness in patients with HCC. Serum TPS levels are affected by the proliferative activity of the underlying chronic liver disease, which is frequently associated with HCC in Chinese patients. As a cell proliferation marker, serum TPS should be interpreted cautiously in the presence of chronic liver disease.
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Wen ZH, Wong CS, Lin CR, Chou AK, Tan PH, Chang YC, Kao CH, Cheng TJ, Yang LC. Changes in the levels of nitric oxide synthase and protein kinase C gamma following kainic acid receptor activation in the rat spinal cord. Neurosci Lett 2001; 309:25-8. [PMID: 11489538 DOI: 10.1016/s0304-3940(01)02014-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this study, we evaluated the levels of nitric oxide synthase, both neuronal and induced (nNOS and iNOS, respectively), cyclooxygenase-1 and 2 (COX-1 and COX-2) and protein kinase C gamma (PKCgamma) and correlated these with algogenic behavior following spinal kainic acid (KA) receptor activation in rats. Thirty adult male Sprague-Dawley rats were randomly assigned into six groups (n=5). Groups A, B, and C received 0.5 g kainic acid intrathecally and were analyzed at 3, 6, 24 h after injection, respectively. Groups D, E, and F received saline and were analyzed at 3, 6, 24 h after injection, respectively. We observed for behavioral changes in the rats following intrathecal KA injection and analyzed the protein levels of NOS, COX and PKCgamma by Western blotting techniques. Importantly, we clarified the potential roles of PKCgamma in the regulation of nNOS and COX-2 following intrathecal injection with KA in the rat spinal cord. COX-2 protein was detected but not significantly changed in the lumbosacral spinal cord at 3, 6, and 24 h following intrathecal KA injection (P>0.05). In contrast, nNOS protein was detected at higher levels in comparison with normal spinal cord at 6 and 24 h after intrathecal administration of KA (P<0.05). PKCgamma also increased significantly at 3, 6, and 24 h after intrathecal KA injection when compared with the baseline level (P<0.05). On the other hand, COX-1 and iNOS were not detected in either normal or KA treated spinal cords. These results provide strong in vivo evidence to support the idea that nNOS but not COX-2, plays an important role in spinal KA receptor activation. Furthermore, up-regulation of PKCgamma is involved in KA induced algogenic behavior in rats.
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Yu LR, Shao XX, Jiang WL, Xu D, Chang YC, Xu YH, Xia QC. Proteome alterations in human hepatoma cells transfected with antisense epidermal growth factor receptor sequence. Electrophoresis 2001; 22:3001-8. [PMID: 11565794 DOI: 10.1002/1522-2683(200108)22:14<3001::aid-elps3001>3.0.co;2-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The epidermal growth factor (EGF) is a member of the growth factor superfamily that can stimulate the proliferation of many types of cells. Overexpression of EGF receptor (EGFR) was observed in many types of cancer cells. Anti-EGFR antibodies or antisense nucleic acid sequences of EGFR can suppress the growth of hepatoma cells. In order to further investigate the proteome alterations associated with malignant growth of the human hepatoma cells and the influence of EGFR signal pathway on the cellular proteome, we have comparatively analyzed the proteomes of human hepatoma cells transfected with antisense EGFR sequence (cell strain JX-1) and its control cells (cell strain JX-0) by two-dimensional (2-D) gel electrophoresis and mass spectrometry. Image analysis of silver-stained 2-D gels revealed that 40 protein spots showed significant expression changes in JX-1 cells compared to JX-0 cells. Three of them, including the tumor suppressor protein maspin, changed with tendency to the normal levels. Two protein spots were identified as HSP27 in the same gel, and one of them had a reduced level in JX-1 cells. The apparent alterations of HSP27 in expression level might be the results from their differential chemical modifications, suggesting the effect of dynamic post-translational modifications of proteins on the growth of hepatoma cells. Other proteins such as glutathione peroxidase (GPX-1) and 14-3-3-sigma also exhibited altered expression in JX-1 cells, and their functional implications are discussed.
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MESH Headings
- Amino Acid Sequence
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/pathology
- Electrophoresis, Gel, Two-Dimensional
- ErbB Receptors/genetics
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic/genetics
- Heat-Shock Proteins/analysis
- Heat-Shock Proteins/biosynthesis
- Heat-Shock Proteins/genetics
- Humans
- Liver Neoplasms/genetics
- Liver Neoplasms/metabolism
- Liver Neoplasms/pathology
- Molecular Sequence Data
- Neoplasm Proteins/analysis
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/genetics
- Oligodeoxyribonucleotides, Antisense/genetics
- Peptide Mapping
- Proteome
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
- Subtraction Technique
- Transfection
- Tumor Cells, Cultured/metabolism
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Chang YC, Guo NW, Wang ST, Huang CC, Tsai JJ. Working memory of school-aged children with a history of febrile convulsions: a population study. Neurology 2001; 57:37-42. [PMID: 11445625 DOI: 10.1212/wnl.57.1.37] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE A prospective, population-based, case-control study was performed to ascertain whether febrile convulsion (FC) in early childhood is associated with specific working memory characteristics in school age. METHODS From a population survey of 4,340 live-birth newborns in Tainan City, Taiwan, 103 children with confirmed FC by age 3 years were followed-up until they were at least 6 years old. Three analogous searching tasks dissociating the mnemonic and executive aspects of performances were administered to 87 of these school-aged children and to 87 randomly selected age-matched control subjects to assess the learning, spatial, and sequential working memory. RESULTS The FC group performed significantly and consistently better than control subjects on all but one working memory measure, jumping errors. Multivariate analysis using linear regression revealed that the onset of FC before age 1 year was the only significant risk factor for deficits in mnemonic function. Prior neurodevelopmental delay was the only significant risk factor for deficits in executive function. Factors such as socioeconomic status, family predisposition for seizures, complex FC, recurrent FC, and subsequent unprovoked seizures were not risk factors for working memory deficits. CONCLUSION The authors found that school-aged children with a history of FC demonstrated significantly better mnemonic capacity, more flexible mental processing, and higher impulsivity than their age-matched control subjects. The underlying mechanism for the facilitated working memory function in children with a history of FC needs further delineation.
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Hung WS, Fang CL, Su CH, Lai WF, Chang YC, Tsai YH. Cytotoxicity and immunogenicity of SACCHACHITIN and its mechanism of action on skin wound healing. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 2001; 56:93-100. [PMID: 11309795 DOI: 10.1002/1097-4636(200107)56:1<93::aid-jbm1072>3.0.co;2-b] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
SACCHACHITIN membrane, a weavable skin substitute made from the residual fruiting body of Ganoderma tsugae, has been demonstrated to promote skin wound healing. Prior to its clinical application, it is critical to learn more about any possible cytotoxicity, immunogenicity, or allergy response, and at least some of its mechanism(s) of action(s). In the present studies, it has been found that SACCHACHITIN suspension at less than 0.05% shows no cytotoxicity to the primary culture of rat fibroblasts. However, at higher concentrations (> or = 0.1%), it does reduce the growth of fibroblasts, based on MTT assays. This might be caused by positive charges on chitin molecules that are too strong, and may be harmful to the cell membrane. SACCHACHITIN showed no immunogenicity after it was inoculated into rats three times; however, the unmodified, purified rabbit type I and type II collagens did. Subcutaneous injection of SACCHACHITIN suspension into rats showed no gross allergic responses on skin. Nevertheless, it did cause local acute inflammation, as observed by histological investigation. This is similar to what occurred in the wound site covered with SACCHACHITIN membrane. The chemotactic effect of SACCHACHITIN was exhibited in both intact and wounded skin tissues. This may be one of the initial beneficial effects of SACCHACHITIN membrane to wound healing. The rapid acute inflammatory process was followed by the appearance of angiogenesis and granulation tissue formation, which occurred earlier than it normally would. Coverage of the wound area with SACCHACHITIN membrane also induced an earlier formation of scar tissue to replace the granulation tissue. A 1.5 x 1.5 cm(2) wound area covered by SACCHACHITIN completely healed by 21 days, while that covered with cotton gauze did not. Therefore, SACCHACHITIN is a safe biomaterial for use as a wound dressing for skin healing. Its promoting action for wound healing might be due to its chemotactic effect for inflammatory cells. This, in turn, may facilitate subsequent angiogenesis, granulation tissue formation, and faster new tissue formation, leading to faster wound healing.
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Chang YC, Okeke BC, Hatsu M, Takamizawa K. In vitro dehalogenation of tetrachloroethylene (PCE) by cell-free extracts of Clostridium bifermentans DPH-1. BIORESOURCE TECHNOLOGY 2001; 78:141-147. [PMID: 11333032 DOI: 10.1016/s0960-8524(01)00005-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Cell-free extracts of Clostridium bifermentans DPH-1 catalyzed tetrachloroethylene (PCE) dechlorination. PCE degradation was stimulated by addition of a variety of electron donors. Ethanol (0.61 mM) was the most effective electron donor for PCE dechlorination. Maximum activity was recorded at 30 degrees C and pH 7.5. Addition of NADH as a cofactor stimulated enzymatic activity but the activity was not stimulated by addition of metal ions. When the cell-free enzyme extract was incubated in the presence of titanium citrate as a reducing agent, the dehalogenase was rapidly inactivated by propyl iodide (0.5 mM). The activity of propyliodide-reacted enzyme was restored by illumination with a 250 W lamp. The dehalogenase activity was also inhibited by cyanide. The substrate spectrum of activity included trichloroethylene (TCE), cis-1,2-dichloroethylene (cDCE), trans-dichloroethylene, 1,1-dichloroethylene, 1,2-dichloroethane, and 1,1,2-trichloroethane. The highest rate of degradation of the chlorinated aliphatic compounds was achieved with PCE, and PCE was principally degraded via TCE to cDCE. Results indicate that the dehalogenase could play a vital role in the breakdown of PCE as well as a variety of other chlorinated aliphatic compounds.
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Peng NH, Mao HC, Chen YC, Chang YC. [Effects of light intensity on the physiological parameters of the premature infant]. HU LI YAN JIU = NURSING RESEARCH 2001; 9:333-343. [PMID: 17953077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This study attempts to find out the effects of light intensity on premature infants' physiological parameters. The research method adopted utilized a quasiexperimental repeated measures design. Thirty-five premature infants born in no more than thirty seven gestation weeks and with birth weight less than 2500g were targeted. The first step was to examine the original arrangement of the blankets over the incubators, the second step was to investigate the effect of placing blankets on the top of the incubator and draped down the top 1/3 of the sides. The third step was conducted without blankets. Factors including light intensity and volume in the incubator and heart rate, respiration rate, and blood oxygen saturation of the premature infants were recorded in all three steps. During the experimental period, no nursing treatment or interventions were allowed. Instruments used in the study included a photometer, a phonometer, a V8 camera, a heart rate monitor, a respiration monitor, and a blood oxygen saturation monitor. The study was conducted in the NICUs in three district hospitals in northern Taiwan. To analyze the data, descriptive statistics and the General Estimation Equation (GEE) were applied. The study shows: (1) Light intensity had a significant statistical relationship with the premature infants' physiological parameters (p = .00). (2) The heart rate and respiration rate increased and the blood oxygen saturation decreased as the intensity of light went up. (3) Placing a blanket over the top and sides of the incubator effectively reduces light levels inside (p = .00). The results of this study suggest a treatment principle for premature infants and provide a basis further research.
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Tsai HF, Fujii I, Watanabe A, Wheeler MH, Chang YC, Yasuoka Y, Ebizuka Y, Kwon-Chung KJ. Pentaketide melanin biosynthesis in Aspergillus fumigatus requires chain-length shortening of a heptaketide precursor. J Biol Chem 2001; 276:29292-8. [PMID: 11350964 DOI: 10.1074/jbc.m101998200] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chain lengths and cyclization patterns of microbial polyketides are generally determined by polyketide synthases alone. Fungal polyketide melanins are often derived from a pentaketide 1,8-dihydroxynaphthalene, and pentaketide synthases are used for synthesis of the upstream pentaketide precursor, 1,3,6,8-tetrahydroxynaphthalene (1,3,6,8-THN). However, Aspergillus fumigatus, a human fungal pathogen, uses a heptaketide synthase (Alb1p) to synthesize its conidial pigment through a pentaketide pathway similar to that which produces 1,8-dihydroxynaphthalene-melanin. In this study we demonstrate that a novel protein, Ayg1p, is involved in the formation of 1,3,6,8-THN by chain-length shortening of a heptaketide precursor in A. fumigatus. Deletion of the ayg1 gene prevented the accumulation of 1,3,6,8-THN suggesting the involvement of ayg1 in 1,3,6,8-THN production. Genetic analyses of double-gene deletants suggested that Ayg1p catalyzes a novel biosynthetic step downstream of Alb1p and upstream of Arp2p (1,3,6,8-THN reductase). Further genetic and biochemical analyses of the reconstituted strains carrying alb1, ayg1, or alb1 + ayg1 indicated that Ayg1p is essential for synthesis of 1,3,6,8-THN in addition to Alb1p. Cell-free enzyme assays, using the crude Ayg1p protein extract, revealed that Ayg1p enzymatically shortened the heptaketide product of Alb1p to 1,3,6,8-THN. Thus, the protein Ayg1p facilitates the participation of a heptaketide synthase in a pentaketide pathway via a novel polyketide-shortening mechanism in A. fumigatus.
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Okeke BC, Chang YC, Hatsu M, Suzuki T, Takamizawa K. Purification, cloning, and sequencing of an enzyme mediating the reductive dechlorination of tetrachloroethylene (PCE) from Clostridium bifermentans DPH-1. Can J Microbiol 2001; 47:448-56. [PMID: 11400736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
An enzyme mediating the reductive dechlorination of tetrachloroethylene (PCE) from cell-free extracts of Clostridium bifermentans DPH-1 was purified, cloned, and sequenced. The enzyme catalyzed the reductive dechlorination of PCE to cis-1,2-dichloroethylene via trichloroethylene, at a Vmax and Km of 73 nmol/mg protein and 12 microM, respectively. Maximal activity was recorded at 35 degrees C and pH 7.5. Enzymatic activity was independent of metal ions but was oxygen sensitive. A mixture of propyl iodide and titanium citrate caused a light-reversible inhibition of enzymatic activity suggesting the involvement of a corrinoid cofactor. The molecular mass of the native enzyme was estimated to be approximately 70 kDa. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrix-assisted laser desorption ionization-time of flight/mass spectrometry (MALDI-TOF/MS) revealed molecular masses of approximately 35 kDa and 35.7 kDa, respectively. A broad spectrum of chlorinated aliphatic compounds (PCE, trichloroethylene, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, 1,1-dichloroethylene, 1,2-dichloropropane, and 1,1,2-trichloroethane) was degraded. With degenerate primers designed from the N-terminal sequence (27 amino acid residues), a partial sequence (81 bp) of the encoding gene was amplified by polymerase chain reaction (PCR) and sequenced. Southern analysis of C. bifermentans genomic DNA using the PCR product as a probe revealed restriction fragment bands. A 5.0 kb ClaI fragment, harboring the relevant gene (designated pceC) was cloned (pDEHAL5) and the complete nucleotide sequence of pceC was determined. The gene showed homology mainly with microbial membrane proteins and no homology with any known dehalogenase, suggesting a distinct PCE dehalogenase.
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Montigny WJ, Houchens CR, Illenye S, Gilbert J, Coonrod E, Chang YC, Heintz NH. Condensation by DNA looping facilitates transfer of large DNA molecules into mammalian cells. Nucleic Acids Res 2001; 29:1982-8. [PMID: 11328883 PMCID: PMC37261 DOI: 10.1093/nar/29.9.1982] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Experimental studies of complete mammalian genes and other genetic domains are impeded by the difficulty of introducing large DNA molecules into cells in culture. Previously we have shown that GST-Z2, a protein that contains three zinc fingers and a proline-rich multimerization domain from the polydactyl zinc finger protein RIP60 fused to glutathione S-transferase (GST), mediates DNA binding and looping in vitro. Atomic force microscopy showed that GST-Z2 is able to condense 130-150 kb bacterial artificial chromosomes (BACs) into protein-DNA complexes containing multiple DNA loops. Condensation of the DNA loops onto the Z2 protein-BAC DNA core complexes with cationic lipid resulted in particles that were readily transferred into multiple cell types in culture. Transfer of total genomic linear DNA containing amplified DHFR genes into DHFR(-) cells by GST-Z2 resulted in a 10-fold higher transformation rate than calcium phosphate co-precipitation. Chinese hamster ovarian cells transfected with a BAC containing the human TP53 gene locus expressed p53, showing native promoter elements are active after GST-Z2-mediated gene transfer. Because DNA condensation by GST-Z2 does not require the introduction of specific recognition sequences into the DNA substrate, condensation by the Z2 domain of RIP60 may be used in conjunction with a variety of other agents to provide a flexible and efficient non-viral platform for the delivery of large genes into mammalian cells.
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