734 results on '"C. Chien"'
Search Results
652. A universal hybrid decision tree classifier design for human activity classification.
- Author
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Chien C and Pottie GJ
- Subjects
- Accelerometry methods, Female, Humans, Male, Predictive Value of Tests, Models, Theoretical, Motor Activity physiology, Software
- Abstract
A system that reliably classifies daily life activities can contribute to more effective and economical treatments for patients with chronic conditions or undergoing rehabilitative therapy. We propose a universal hybrid decision tree classifier for this purpose. The tree classifier can flexibly implement different decision rules at its internal nodes, and can be adapted from a population-based model when supplemented by training data for individuals. The system was tested using seven subjects each monitored by 14 triaxial accelerometers. Each subject performed fourteen different activities typical of daily life. Using leave-one-out cross validation, our decision tree produced average classification accuracies of 89.9%. In contrast, the MATLAB personalized tree classifiers using Gini's diversity index as the split criterion followed by optimally tuning the thresholds for each subject yielded 69.2%.
- Published
- 2012
- Full Text
- View/download PDF
653. Estimation of accelerometer orientation for activity recognition.
- Author
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Friedman A, Hajj Chehade N, Chien C, and Pottie G
- Subjects
- Actigraphy methods, Calibration, Computer Simulation, Equipment Design, Equipment Failure Analysis, Humans, Monitoring, Ambulatory methods, Reproducibility of Results, Sensitivity and Specificity, Accelerometry, Actigraphy instrumentation, Models, Biological, Monitoring, Ambulatory instrumentation, Movement physiology, Orientation physiology, Pattern Recognition, Automated methods
- Abstract
Tri-axial accelerometers have been widely used for human activity recognition and classification. A main challenge in accelerometer-based activity recognition is the system dependence on the orientation of the accelerometer. This paper presents an approach for overcoming this challenge by calibrating the accelerometer orientation using pre-defined activities alongside automated correction algorithms. This method includes manipulation of data via rotation matrices estimated from the pre-defined activities. The system is subsequently tested with real data where sensors were placed in the wrong orientation. A control set of correctly oriented sensors were also placed for validation purposes. We show that our approach improves the accuracy from 38% to 92% for the wrongly oriented sensors, when the control sensors achieve 95%. A GUI was also created in order to make the tool easily available to other researchers.
- Published
- 2012
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654. Disseminated asymptomatic yellowish papules on the face, trunk and limbs in a 3-year-old boy.
- Author
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Ching-Fu H, Bai-Yao W, Wei-Ming W, and Chien-Ping C
- Subjects
- Child, Preschool, Humans, Male, Sebaceous Gland Diseases blood, Sebaceous Gland Diseases diagnosis, Skin Diseases blood, Xanthomatosis blood, Extremities pathology, Face pathology, Skin Diseases diagnosis, Xanthomatosis diagnosis
- Published
- 2011
- Full Text
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655. A new surgical approach to Dupuytren's disease.
- Author
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Edmunds I and Chien C
- Subjects
- Adult, Aged, Aged, 80 and over, Dermatologic Surgical Procedures, Fasciotomy, Female, Fingers physiopathology, Fingers surgery, Follow-Up Studies, Humans, Male, Middle Aged, Postoperative Complications etiology, Postoperative Complications physiopathology, Postoperative Complications surgery, Prospective Studies, Range of Motion, Articular physiology, Reoperation, Surgical Flaps, Dupuytren Contracture surgery, Suture Techniques
- Abstract
We present a new surgical approach for Dupuytren's disease which overcomes some of the problems seen with traditional approaches. The approach is simple but allows full exposure and accommodates all options for closure. It comprises transverse incisions at the skin creases of the digit joined by oblique incisions at 45°. The transverse incisions can be extended to the mid-axial line for improved exposure and skin release and to lateralize the apices of the scar. After excision of the disease and correction of the contracture the wound can be assessed and closed primarily, with advancement flaps or skin grafts, or left partially open. This study includes surgery on 105 rays in 75 patients with excellent results in 80 rays, good results in 20 rays, fair results in four rays and a poor result in one ray. There was only one significant complication.
- Published
- 2011
- Full Text
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656. Markedly elevated serum calcitonin concentrations associated with initial presentation but not the recurrent presentation of medullary thyroid carcinoma.
- Author
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Bodenner D, Nalley C, Chien C, Clarke B, Spring PM, and Stack BC
- Subjects
- Aged, Biopsy, Fine-Needle, Carcinoma, Medullary surgery, Chromogranin A chemistry, Disease Progression, Fatal Outcome, Gene Expression Regulation, Neoplastic, Humans, Immunohistochemistry methods, Male, Neoplasm Metastasis, Thyroid Neoplasms surgery, Calcitonin blood, Carcinoma, Medullary blood, Carcinoma, Medullary diagnosis, Thyroid Neoplasms blood, Thyroid Neoplasms diagnosis
- Published
- 2010
- Full Text
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657. Chemical genetics strategy identifies an HCV NS5A inhibitor with a potent clinical effect.
- Author
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Gao M, Nettles RE, Belema M, Snyder LB, Nguyen VN, Fridell RA, Serrano-Wu MH, Langley DR, Sun JH, O'Boyle DR 2nd, Lemm JA, Wang C, Knipe JO, Chien C, Colonno RJ, Grasela DM, Meanwell NA, and Hamann LG
- Subjects
- Adolescent, Adult, Animals, Antiviral Agents blood, Antiviral Agents chemistry, Antiviral Agents therapeutic use, Carbamates, Cell Line, Chlorocebus aethiops, Drug Resistance, Viral, Female, Genotype, HeLa Cells, Hepatitis C drug therapy, Hepatitis C virology, Humans, Imidazoles blood, Imidazoles chemistry, Inhibitory Concentration 50, Male, Middle Aged, Pyrrolidines, Time Factors, Valine analogs & derivatives, Vero Cells, Viral Load drug effects, Young Adult, Antiviral Agents pharmacology, Hepacivirus drug effects, Imidazoles pharmacology, Viral Nonstructural Proteins antagonists & inhibitors
- Abstract
The worldwide prevalence of chronic hepatitis C virus (HCV) infection is estimated to be approaching 200 million people. Current therapy relies upon a combination of pegylated interferon-alpha and ribavirin, a poorly tolerated regimen typically associated with less than 50% sustained virological response rate in those infected with genotype 1 virus. The development of direct-acting antiviral agents to treat HCV has focused predominantly on inhibitors of the viral enzymes NS3 protease and the RNA-dependent RNA polymerase NS5B. Here we describe the profile of BMS-790052, a small molecule inhibitor of the HCV NS5A protein that exhibits picomolar half-maximum effective concentrations (EC(50)) towards replicons expressing a broad range of HCV genotypes and the JFH-1 genotype 2a infectious virus in cell culture. In a phase I clinical trial in patients chronically infected with HCV, administration of a single 100-mg dose of BMS-790052 was associated with a 3.3 log(10) reduction in mean viral load measured 24 h post-dose that was sustained for an additional 120 h in two patients infected with genotype 1b virus. Genotypic analysis of samples taken at baseline, 24 and 144 h post-dose revealed that the major HCV variants observed had substitutions at amino-acid positions identified using the in vitro replicon system. These results provide the first clinical validation of an inhibitor of HCV NS5A, a protein with no known enzymatic function, as an approach to the suppression of virus replication that offers potential as part of a therapeutic regimen based on combinations of HCV inhibitors.
- Published
- 2010
- Full Text
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658. Statin therapy in patients with diastolic heart failure.
- Author
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Tehrani F, Morrissey R, Phan A, Chien C, and Schwarz ER
- Subjects
- Aged, Aged, 80 and over, Female, Heart Failure, Diastolic mortality, Heart Failure, Diastolic physiopathology, Hospital Mortality, Hospitalization statistics & numerical data, Humans, Male, Proportional Hazards Models, Statistics, Nonparametric, Survival Rate, Treatment Outcome, Heart Failure, Diastolic drug therapy, Hydroxymethylglutaryl-CoA Reductase Inhibitors therapeutic use
- Abstract
Background: There is controversy regarding the potential effects of statin therapy on mortality in patients with heart failure. The present study analyzed the possible effects of statin therapy on morbidity and mortality in patients with diastolic heart failure over long-term follow-up., Hypothesis: To evaluate potential effect of statin therapy on hospitalization rate and mortality in patients with diastolic heart failure., Methods: Patients with preserved left ventricular ejection fraction (> or =50%), hospitalized for clinical symptoms of heart failure were evaluated. Patients on statin therapy started at or prior to their first heart failure admission represented group 1 and patients without statin therapy represented group 2. The effects of statins on hospitalization rates and mortality were assessed during a 5 year follow-up., Results: A total of 270 patients (group 1 n = 81; group 2 n = 189) were followed over 5 years. Patients on statins demonstrated improved survival compared to patients without statin therapy (hazard ratio [HR] = 0.65, 95% confidence interval [CI]: 0.45-0.95, P = .029). The survival benefit was maintained after adjusting for differences in baseline characteristics, comorbidities, and other medications. There was no significant difference in the mean cardiovascular hospitalization rate (3.0 +/- 3.2 vs 3.8 +/- 4.7, P = .23) and in overall hospitalization rate (7.1 +/- 6.3 vs 7.8 +/- 7.7, P = .52) between groups 1 and 2, respectively., Conclusion: Statin therapy appears to be associated with improved survival in patients with diastolic heart failure., (Copyright 2009 Wiley Periodicals, Inc.)
- Published
- 2010
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659. Analysis of a switch from enfuvirtide to raltegravir in patients with undetectable viral load: efficacy and quality of life at 24 weeks.
- Author
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Sayana S, Prosser P, Ricaurte JC, Sanchez S, Hamwi G, Hershey-Weber J, Chien C, Easley A, Nguyen T, Wilson L, and Khanlou H
- Subjects
- Adult, Drug Administration Schedule, Enfuvirtide, Female, HIV Envelope Protein gp41 therapeutic use, HIV Fusion Inhibitors administration & dosage, HIV Fusion Inhibitors therapeutic use, HIV Infections virology, HIV Integrase Inhibitors administration & dosage, HIV Integrase Inhibitors therapeutic use, HIV-1 physiology, Humans, Male, Middle Aged, Peptide Fragments therapeutic use, Pyrrolidinones therapeutic use, Raltegravir Potassium, Surveys and Questionnaires, Time Factors, Treatment Outcome, HIV Envelope Protein gp41 administration & dosage, HIV Infections drug therapy, HIV-1 drug effects, Peptide Fragments administration & dosage, Pyrrolidinones administration & dosage, Quality of Life, Viral Load
- Published
- 2009
- Full Text
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660. The impact of methanogenesis on flow and transport in coarse sand.
- Author
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Ye S, Sleep BE, and Chien C
- Subjects
- Bacteria, Anaerobic physiology, Biodegradation, Environmental, Biofilms growth & development, Chlorine metabolism, Electrons, Solvents metabolism, Water chemistry, Water Movements, Water Pollutants, Chemical metabolism, Water Purification, Bacteria, Anaerobic metabolism, Methane biosynthesis, Silicon Dioxide
- Abstract
The effects of biofilm growth and methane gas generation on water flow in porous media were investigated in an anaerobic two-dimensional sand-filled cell. Inoculation of the lower portion of the cell with a methanogenic culture and addition of methanol to the bottom of the cell led to biomass growth and formation of a gas phase. Biomass distributions in the water and on the sand in the cell were measured by protein analysis. The biofilm distribution on sand was observed by confocal laser scanning microscopy. The formation, migration, distribution and saturation of gases in the cell were visualized by the charge-coupled device (CCD) camera. The effects of biofilm and gas generation on water flow were separated by performing one tracer test in the presence of both biofilm and a gas phase and a second tracer test after removal of the gas phase through water flushing. The results of tracer tests demonstrated that flow and transport in the two-dimensional cell were significantly affected by both gas generation and biofilm growth. Gas generated at the bottom of the cell in the biologically active zone moved upwards in discrete fingers, so that gas phase saturations (gas-filled fraction of void space) in the biologically active zone at the bottom of the cell did not exceed 40-50%, while gas accumulation at the top of the cell produced gas phase saturations as high as 80%. The greatest reductions in water phase permeability, based on measurements of reductions in water phase saturations, occurred near the top of the box as a result of the gas accumulation. In contrast the greatest reductions in permeability due to biofilm growth, based on measurements of biofilm thickness, occurred in the most biologically active zone at the bottom of the cell, where gas phase saturations were approximately 40-50%, but permeability reductions due to biofilm growth were estimated to be 80-95%.
- Published
- 2009
- Full Text
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661. The prognostic value of anemia in patients with diastolic heart failure.
- Author
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Tehrani F, Phan A, Morrissey R, Chien C, Rafique A, and Schwarz ER
- Subjects
- Aged, Aged, 80 and over, Anemia blood, Anemia mortality, Female, Heart Failure, Diastolic mortality, Heart Failure, Diastolic physiopathology, Hemoglobins metabolism, Hospitalization, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Prognosis, Proportional Hazards Models, Retrospective Studies, Risk Assessment, Risk Factors, Stroke Volume, Time Factors, Ventricular Function, Left, Anemia etiology, Heart Failure, Diastolic complications
- Abstract
Anemia is prevalent in heart-failure patients, and it has been associated with increased mortality rates. In a retrospective study, we evaluated the effects of anemia on long-term survival in patients who experienced purely diastolic heart failure.Heart-failure patients with preserved systolic function (left ventricular ejection fraction, > or =0.50) were evaluated retrospectively. Of 294 patients, 162 had anemia (group 1) and 132 had no anemia (group 2) upon baseline examination. Anemia was defined as a hemoglobin level below 12 g/dL in women and below 13 g/dL in men. Multivariate Cox proportional hazards regression was conducted in order to test whether hemoglobin levels were an independent predictor of 5-year hospitalization and mortality rates in patients with diastolic heart failure. A P value less than 0.05 was considered statistically significant.Group 1 patients had a shorter mean survival time (37.8 +/- 1.8 vs 44.9 +/- 1.8 mo, P = 0.01); however, there was no significant difference between the groups in hospitalization rate (7.2 +/- 7.1 vs 7.5 +/- 6.3, P = 0.677). In a subgroup analysis, anemia was a significant predictor of higher mortality rates in elderly patients (age, >75 yr) who had diastolic heart failure (P = 0.018).We found that anemia is associated with increased long-term mortality rates in patients who have diastolic heart failure. In addition, anemia appears to be an independent predictor of worse outcomes in elderly heart-failure patients.
- Published
- 2009
662. A positive modulator of K Ca 2 and K Ca 3 channels, 4,5-dichloro-1,3-diethyl-1,3-dihydro-benzoimidazol-2-one (NS4591), inhibits bladder afferent firing in vitro and bladder overactivity in vivo.
- Author
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Hougaard C, Fraser MO, Chien C, Bookout A, Katofiasc M, Jensen BS, Rode F, Bitsch-Nørhave J, Teuber L, Thor KB, Strøbaek D, Burgard EC, and Rønn LC
- Subjects
- Action Potentials drug effects, Action Potentials physiology, Animals, Calcium Chloride pharmacology, Cell Line, Cell Membrane drug effects, Cell Membrane physiology, Chloride Channels drug effects, Female, Ganglia, Spinal drug effects, Ganglia, Spinal physiology, Humans, Kidney, Magnesium Chloride pharmacology, Neurons drug effects, Potassium pharmacology, Potassium Channels drug effects, Potassium Channels physiology, Rats, Rats, Sprague-Dawley, Small-Conductance Calcium-Activated Potassium Channels drug effects, Urinary Bladder drug effects, Urination drug effects, Urination physiology, Afferent Pathways drug effects, Benzimidazoles pharmacology, Chloride Channels physiology, Neurons physiology, Small-Conductance Calcium-Activated Potassium Channels physiology, Urinary Bladder innervation, Urinary Bladder physiology
- Abstract
Calcium-activated potassium channels are attractive targets for the development of therapeutics for overactive bladder. In the current study, we addressed the role of calcium-activated potassium channels of small (SK; K(Ca)2) and intermediate (IK; K(Ca)3) conductance in bladder function pharmacologically. We identified and characterized a novel positive modulator of SK/IK channels, 4,5-dichloro-1,3-diethyl-1,3-dihydro-benzoimidazol-2-one (NS4591). In whole-cell patch-clamp experiments, NS4591 doubled IK-mediated currents at a concentration of 45 +/- 6 nM(n = 16), whereas 530 +/- 100 nM (n = 7) was required for doubling of SK3-mediated currents. In acutely dissociated bladder primary afferent neurons, the presence of SK channels was verified using apamin and 1-ethyl-2-benzimidazolinone. In these neurons, NS4591 (10 microM) inhibited the number of action potentials generated by suprathreshold depolarizing pulses. NS4591 also reduced carbachol-induced twitches in rat bladder detrusor rings in an apamin-sensitive manner. In vivo, NS4591 (30 mg/kg) inhibited bladder overactivity in rats and cats induced by capsaicin and acetic acid, respectively. In conclusion, the present study supports the involvement of calcium-activated potassium channels in bladder function and identifies NS4591 as a potent modulator of IK and SK channels that is effective in animal models of bladder overactivity.
- Published
- 2009
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663. Structure and bioactivity of the polysaccharides in medicinal plant Dendrobium huoshanense.
- Author
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Hsieh YS, Chien C, Liao SK, Liao SF, Hung WT, Yang WB, Lin CC, Cheng TJ, Chang CC, Fang JM, and Wong CH
- Subjects
- Animals, Arabinose analysis, Carbohydrate Sequence, Cell Proliferation drug effects, Cell Wall chemistry, Chemical Fractionation, Cytokines biosynthesis, Medicine, Chinese Traditional, Mice, Molecular Sequence Data, Pectins analysis, Pentoses analysis, Plant Leaves chemistry, Plant Stems chemistry, Polysaccharides isolation & purification, Polysaccharides pharmacology, Spleen cytology, Spleen immunology, Spleen metabolism, Xylans analysis, Dendrobium chemistry, Plants, Medicinal chemistry, Polysaccharides chemistry
- Abstract
Detailed structures of the active polysaccharides extracted from the leaf and stem cell walls and mucilage of Dendrobium huoshanense are determined by using various techniques, including chromatographic, spectroscopic, chemical, and enzymatic methods. The mucilage polysaccharide exhibits specific functions in activating murine splenocytes to produce several cytokines including IFN-gamma, IL-10, IL-6, and IL-1alpha, as well as hematopoietic growth factors GM-CSF and G-CSF. However, the deacetylated mucilage obtained from an alkaline treatment fails to induce cytokine production. The structure and bioactivity of mucilage components are validated by further fractionation. This is the first study that provides clear evidence for the structure and activity relationship of the polysaccharide in D. huoshanense.
- Published
- 2008
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664. Long-term effects of antihypertensive drugs on the risk of new-onset diabetes in elderly Taiwanese hypertensives.
- Author
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Liou YS, Ma T, Tien L, Chien C, Chou P, and Jong GP
- Subjects
- Adrenergic beta-Antagonists adverse effects, Adrenergic beta-Antagonists therapeutic use, Age of Onset, Aged, Aged, 80 and over, Angiotensin II Type 1 Receptor Blockers adverse effects, Angiotensin II Type 1 Receptor Blockers therapeutic use, Angiotensin-Converting Enzyme Inhibitors adverse effects, Angiotensin-Converting Enzyme Inhibitors therapeutic use, Antihypertensive Agents therapeutic use, Calcium Channel Blockers adverse effects, Calcium Channel Blockers therapeutic use, Diabetes Mellitus diagnosis, Diuretics adverse effects, Diuretics therapeutic use, Female, Humans, Hypertension drug therapy, Male, Retrospective Studies, Risk Factors, Taiwan, Time Factors, Antihypertensive Agents adverse effects, Diabetes Mellitus chemically induced, Hypertension complications
- Abstract
Antihypertensive drugs have been linked to new-onset diabetes (NOD); however, the effects of these drugs on the development of NOD in elderly Taiwanese hypertensive patients have not been well determined. We examined the association between antihypertensive drug therapy and the risk of NOD in a population-based study. The sample consisted of 8,638 elderly hypertensive patients. The data were obtained from claim forms provided to the central region branch of the Bureau of National Health Insurance in Taiwan from January 2001 to December 2006. Prescriptions for antihypertensive drugs before the index date were retrieved from a prescription database. We estimated the odds ratios (ORs) of NOD associated with antihypertensive drug use; nondiabetic subjects served as the reference group. The risk of NOD was higher among users of diuretics (OR, 1.12; 95% confidence interval [CI], 1.04-1.21), and beta-blockers (OR, 1.11; 95% CI, 1.02-1.20) than among nonusers. Patients who take angiotensin-converting enzyme (ACE) inhibitors (OR, 0.90; 95% CI, 0.82-0.98) or alpha-blockers (OR, 0.88; 95% CI, 0.78-0.99) are at a lower risk of developing NOD than nonusers. Angiotensin receptor blockers, calcium channel blockers, and vasodilators were not associated with risk of NOD. The results suggest that elderly hypertensive patients who take ACE inhibitors or alpha-blockers are at lower risk of NOD. Diuretics and beta-blockers were associated with a significant increase in the risk of NOD.
- Published
- 2008
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665. Comparison of the Short-Form Survey 12 and the MacNew Heart Disease Health-Related Quality of Life Survey among patients with cardiac disease.
- Author
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Sansgiry SS, Chien C, Jayawant SS, and Raju A
- Subjects
- Adult, Aged, Aged, 80 and over, Cross-Sectional Studies, Female, Heart Diseases psychology, Humans, Male, Middle Aged, Health Status Indicators, Health Surveys, Heart Diseases epidemiology, Quality of Life psychology
- Abstract
Background: Health-related quality of life (HRQL) is an important outcome, especially for chronic diseases with no cure such as cardiovascular diseases., Objective: To investigate the comparability of 2 HRQL instruments, the Short Form-12 (SF-12) survey and the MacNew Heart Disease HRQL survey (MacNew) in patients with cardiac diseases., Methods: A nonexperimental cross-sectional study was conducted in a lipid clinic in the Houston metropolitan area. Patients with a prior cardiac disease were requested to complete the SF-12 and the MacNew scales while waiting to see the physician during their regular clinic visit. Cronbach's alpha values were estimated to evaluate internal consistency. Spearman's correlation was performed to examine the correlation between the SF-12 and the MacNew scale domains., Results: A total of 118 patients were enrolled in this study. High Cronbach's alpha (from 0.89 to 0.94) were observed from all component scores in the MacNew scales. Physical component scores from the SF-12 and from the MacNew were highly correlated (r = 0.74; p < 0.001), as were the mental component score from the SF-12 and the emotional component score from the MacNew (r = 0.68; p < 0.001)., Conclusions: The SF-12 and the MacNew appeared to be strongly correlated to each other for predicting a patient's HRQL in patients with a cardiac disease.
- Published
- 2008
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666. Nosocomial acinetobacter genomic species 13 TU endocarditis following an endoscopic procedure.
- Author
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Yu-Hsien L, Te-Li C, Chien-Pei C, and Chen-Chi T
- Subjects
- Acinetobacter Infections diagnosis, Acinetobacter Infections drug therapy, Acinetobacter baumannii pathogenicity, Acinetobacter calcoaceticus pathogenicity, Aged, Anti-Bacterial Agents therapeutic use, Cross Infection diagnosis, Cross Infection drug therapy, Endocarditis, Bacterial diagnosis, Endocarditis, Bacterial drug therapy, Endocardium microbiology, Humans, Male, Acinetobacter Infections etiology, Cross Infection etiology, Endocarditis, Bacterial etiology, Endoscopy, Gastrointestinal adverse effects
- Abstract
We report a rare case of prosthetic valve endocarditis caused by Acinetobacter genomic species 13 TU. This patient had rheumatic heart disease and received prosthetic mitral valve replacement eleven years previously. He was admitted due to tarry stool. Endoscopic procedure showed two gastric ulcers and some mucous breaks at the distal esophagus. He had a fever on the eleventh hospital day. Persistent Acinetobacter bacteremia was noted with conjunctiva hemorrhage. The pathogen was identified as Acinetobacter genomic species 13 TU by PCR-based method. According to his whole course of disease, the most possible portal of entry was via the endoscopic procedure.
- Published
- 2008
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667. Microbial diversity of soil bacteria in agricultural field contaminated with heavy metals.
- Author
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Chien C, Kuo Y, Chen C, Hung C, Yeh C, and Yeh W
- Subjects
- Bacteria genetics, Bacteria growth & development, Cadmium analysis, Cadmium toxicity, DNA, Bacterial chemistry, DNA, Bacterial genetics, Drug Resistance, Bacterial, Metals, Heavy toxicity, Molecular Sequence Data, Myxococcales drug effects, Myxococcales genetics, Myxococcales growth & development, Polymerase Chain Reaction, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Sphingomonas drug effects, Sphingomonas genetics, Sphingomonas growth & development, Bacteria drug effects, Biodiversity, Metals, Heavy analysis, Soil analysis, Soil Microbiology
- Abstract
In this study we evaluated the bacterial diversity in a soil sample from a site next to a chemical industrial factory previously contaminated with heavy metals. Analysis of 16S rDNA sequences amplified from DNA directly extracted from the soil revealed 17 different bacterial types (genera and/or species). They included Polyangium spp., Sphingomonas spp., Variovorax spp., Hafina spp., Clostridia, Acidobacteria, the enterics and some uncultured strains. Microbes able to tolerate high concentrations of cadmium (500 micromol/L and above) were also isolated from the soil. These isolates included strains of Acinetobacter (strain CD06), Enterobacter sp. (strains CD01, CD03, CD04 and CD08) (similar strains also identified in culture-independent approach) and a strain of Stenotrophomonas sp. The results indicated that the species identified from direct analysis of 16S rDNA of the soil can be quite different from those strains obtained from enrichment cultures and the microbial activities for heavy metal resistance might be more appropriately addressed by the actual isolates.
- Published
- 2008
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668. Advances in computed tomography-based evaluation of coronary arteries: a review of coronary artery imaging with multidetector spiral computed tomography.
- Author
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Chien C, Feng YF, and Arora RR
- Subjects
- Humans, Stents, Coronary Angiography, Coronary Artery Disease diagnostic imaging, Coronary Stenosis diagnostic imaging, Coronary Vessels pathology, Tomography, Spiral Computed
- Abstract
Noninvasive imaging of coronary arteries with computed tomography (CT) has become increasingly accurate with the technological advances in multidetector CT (MDCT). The authors review the utility of MDCT in quantitative and qualitative evaluations of coronary stenosis, plaques, bypass grafts, and stents. Recent studies demonstrate a high accuracy of MDCT in locating significant coronary stenosis, which may allow CT angiography to become an important screening tool for coronary artery disease in selected patient populations. Although factors such as arrhythmias, heart rate, calcifications, and patients' ability to hold their breath may limit the patient population that will ultimately benefit from this technology, MDCT coronary angiography has significant clinical potential. Studies are still needed to clarify the clinical role for CT angiography, but advances in this noninvasive technology are impressive and hold promise for clinical utility.
- Published
- 2007
669. In vitro metabolism of the epoxide substructure of cryptophycins by cytosolic glutathione S-transferase: species differences and stereoselectivity.
- Author
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Cannady EA, Chien C, Jones TM, and Borel AG
- Subjects
- Animals, Chromatography, Liquid, Cytosol metabolism, Dinitrochlorobenzene metabolism, Dogs, Epoxide Hydrolases metabolism, Humans, Mass Spectrometry, Molecular Structure, Species Specificity, Depsipeptides chemistry, Depsipeptides metabolism, Epoxy Compounds metabolism, Glutathione Transferase metabolism
- Abstract
The enzyme kinetics of the glutathione (GSH) conjugation of cryptophycin 52 (C52, R-stereoisomer) and cryptophycin 53 (C53, S-stereoisomer) by cytosolic glutathione S-transferases (cGSTs) from human, rat, mouse, dog and monkey liver were studied. Vmax, Km, and CLint values for glutathione conjugation of C52 (R-stereoisomer) were 0.10 +/- 0.01 nmol min-1 mg-1, 3.24 +/- 0.23 microM, and (3.15 +/- 0.09) x 10(-2) ml min-1 mg-1, respectively, in human cytosol. Due to limited solubility relative to the Km, only CLint values were determined in rat ((7.76 +/- 0.10) x 10-2 ml min-1 mg-1) and mouse ((7.61 +/- 0.50) x 10(-2) ml min-1 mg-1) cytosol. Enzyme kinetic parameters could not be determined for C53 (S-stereoisomer). Microsomal GSH conjugation in human, rat, and mouse was attributed to cytosolic contamination. No GSH conjugation was seen in any biological matrix from dog or monkey. There was little GSH conjugation of C53 by cytosol or microsomes from any species. The metabolism of C52 and C53 by epoxide hydrolase was also investigated. No diol product was observed in any biological matrix from any species. Thus, cGSTs are primarily responsible for C52 metabolism.
- Published
- 2006
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670. The safety and efficacy of dose-sparing intradermal administration of influenza vaccine in human immunodeficiency virus-positive patients.
- Author
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Khanlou H, Sanchez S, Babaie M, Chien C, Hamwi G, Ricaurte JC, Stein T, Bhatti L, Denouden P, and Farthing C
- Subjects
- Adult, Aged, Ambulatory Care Facilities, Antibodies, Viral blood, California epidemiology, Female, Humans, Influenza, Human immunology, Injections, Intradermal, Injections, Intramuscular, Male, Middle Aged, HIV Infections epidemiology, Influenza A virus immunology, Influenza B virus immunology, Influenza Vaccines administration & dosage, Influenza, Human prevention & control
- Published
- 2006
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671. Pre-clinical in vitro and in vivo studies to examine the potential use of photodynamic therapy in the treatment of osteomyelitis.
- Author
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Bisland SK, Chien C, Wilson BC, and Burch S
- Subjects
- Aminolevulinic Acid radiation effects, Animals, Biofilms growth & development, Cell Survival drug effects, Cell Survival radiation effects, Disease Models, Animal, Drug Evaluation, Preclinical, Female, Implants, Experimental microbiology, In Vitro Techniques, Luminescent Measurements, Methylene Blue chemistry, Osteomyelitis microbiology, Photosensitizing Agents radiation effects, Rats, Rats, Sprague-Dawley, Staphylococcus aureus drug effects, Staphylococcus aureus physiology, Staphylococcus aureus radiation effects, Aminolevulinic Acid therapeutic use, Light, Osteomyelitis drug therapy, Photochemotherapy, Photosensitizing Agents therapeutic use
- Abstract
Osteomyelitis can lead to severe morbidity and even death resulting from an acute or chronic inflammation of the bone and contiguous structures due to fungal or bacterial infection. Incidence approximates 1 in 1000 neonates and 1 in 5000 children in the United States annually and increases up to 0.36% and 16% in adults with diabetes or sickle cell anaemia, respectively. Current regimens of treatment include antibiotics and/or surgery. However, the increasing number of antibiotic resistant pathogens suggests that alternate strategies are required. We are investigating photodynamic therapy (PDT) as one such alternate treatment for osteomyelitis using a bioluminescent strain of biofilm-producing staphylococcus aureus (S. aureus) grown onto kirschner wires (K-wire). S. aureus-coated K-wires were exposed to methylene blue (MB) or 5-aminolevulinic acid (ALA)-mediated PDT either in vitro or following implant into the tibial medullary cavity of Sprague-Dawley rats. The progression of S. aureus biofilm was monitored non-invasively using bioluminescence and expressed as a percentage of the signal for each sample immediately prior to treatment. S. aureus infections were subject to PDT 10 days post inoculation. Treatment comprised administration of ALA (300 mg kg(-1)) intraperitoneally followed 4 h later by light (635 +/- 10 nm; 75 J cm(-2)) delivered transcutaneously via an optical fiber placed onto the tibia and resulted in significant delay in bacterial growth. In vitro, MB and ALA displayed similar cell kill with > or =4 log(10) cell kill. In vivo, ALA-mediated PDT inhibited biofilm implants in bone. These results confirm that MB or ALA-mediated PDT have potential to treat S. aureus cultures grown in vitro or in vivo using an animal model of osteomyelitis.
- Published
- 2006
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672. Contrast-enhanced in vivo imaging of breast and prostate cancer cells by MRI.
- Author
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Rodriguez O, Fricke S, Chien C, Dettin L, VanMeter J, Shapiro E, Dai HN, Casimiro M, Ileva L, Dagata J, Johnson MD, Lisanti MP, Koretsky A, and Albanese C
- Subjects
- Animals, Breast Neoplasms metabolism, Breast Neoplasms ultrastructure, Cell Line, Tumor, Estrogens metabolism, Humans, Male, Mice, Microscopy, Atomic Force, Microscopy, Electron, Transmission, Neoplasm Transplantation, Prostatic Neoplasms ultrastructure, Proto-Oncogene Proteins c-myc metabolism, Rats, Vascular Endothelial Growth Factor A metabolism, Breast Neoplasms pathology, Contrast Media analysis, Image Enhancement methods, Magnetic Resonance Imaging methods, Prostatic Neoplasms pathology
- Abstract
The development of effective cancer therapies has been hampered, in part, by the inability to noninvasively follow tumor progression from the initial cancerous lesion through to metastasis. We have previously shown that superparamagnetic iron oxide particles can be used as magnetic resonance imaging contrast agents to label embryonic, mesenchymal and hematopoietic stem cells in vivo. Improving the capacity to non-invasively image cancer progression is an appealing method that could be useful for assessing the efficacy of anticancer therapies. We have established that human prostate (LNCaP, DU145, PC3), rodent prostate (TRAMPC1, YPEN-1), human breast (MDA-MB-231) and mouse mammary (Myc/VEGF) cancer cell lines were readily labeled by fluorescent superparamagnetic sub-micron particles of iron oxide (MPIOs). The MPIOs were essentially inert with respect to cell proliferation and tumor formation. Fluorescence stereomicroscopy and three dimensional magnetic resonance imaging (MRI) determined that subcutaneous, intramuscular or orthotopically implanted labeled cancer cells could be imaged, in vivo, despite in some cases being undetectable by manual palpation. The MPIO-labeled cancer cells could also be imaged, in vivo, at least 6 weeks after implantation. The fluorescent MPIOs further allowed for the ex vivo identification of tumors cells from histological sections. This study demonstrates the feasibility of using fluorescent MPIOs in prostate and breast cancer cell lines as both a negative contrast agent for in vivo MRI as well as a fluorescent tumor marker for optical imaging in vivo and ex vivo.
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- 2006
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673. A study on the clinical effects of physical therapy and acupuncture to treat spontaneous frozen shoulder.
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Ma T, Kao MJ, Lin IH, Chiu YL, Chien C, Ho TJ, Chu BC, and Chang YH
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- Bursitis physiopathology, Combined Modality Therapy, Female, Humans, Integrative Medicine methods, Male, Middle Aged, Quality of Life, Range of Motion, Articular, Surveys and Questionnaires, Treatment Outcome, Acupuncture Therapy methods, Bursitis therapy, Physical Therapy Modalities
- Abstract
The integration of traditional Chinese and Western medicine and their clinical effects have been widely evaluated. Many studies have shown that using a combination of these two remedies has resulted in better outcomes than using only one of them. Acupuncture is a traditional Chinese medical technique, which plays an important role in enforcing pain control, prevention and functional improvement. In 1979, the World Health Organization (WHO) journal introduced acupuncture as a remedy for 43 diseases, including frozen shoulder. This study aims to assess the therapeutic outcomes of combining acupuncture and physical therapy to treat frozen shoulder, and hopes to establish an evidence-based study of the integration of acupuncture and western medicine in the future. A total of 75 frozen shoulder patients treated in a medical center were recruited for the study between January 2002 and December 2002. The average age of these patients was 54.8 years. The average duration of the condition was 25.8 weeks before treatment. Of the 75 patients, 30 were treated by physical therapy, 30 by acupuncture and 15 by both remedies. Before the treatment began, all patients were evaluated by assessing static pain scale, motion pain scale, active and passive ROM (range of motion) and quality of life scale sheet SF-36 (Short Form-36). The outcome was evaluated by follow-up assessments conducted at the 2nd week and 4th week of treatment sessions. All patients showed improvement in quality of life (Short Form-36). Pain was controlled better by acupuncture while ROM improved following physical therapy. However, patients treated by both methods had the best outcome. The integration of acupuncture and physical therapy to treat frozen shoulder leads to a better outcome than using only one method. The author suggests that an evidence-based foundation of the integration of Chinese and Western medicine should be established in the future, to encourage the integration of Chinese and Western medicine.
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- 2006
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674. Antidepressant use and breast cancer risk.
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Chien C, Li CI, Heckbert SR, Malone KE, Boudreau DM, and Daling JR
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- Aged, Case-Control Studies, Female, Humans, Receptors, Estrogen analysis, Receptors, Progesterone analysis, Risk Factors, Selective Serotonin Reuptake Inhibitors adverse effects, Antidepressive Agents adverse effects, Breast Neoplasms chemically induced
- Abstract
Background: Antidepressants are among the most commonly prescribed drugs in the United States. Laboratory studies suggest that because certain antidepressants increase prolactin levels that they may also increase breast cancer risk. However, human studies evaluating use of antidepressants in relation to breast cancer risk have yielded inconsistent results., Methods: A population-based case-control study consisting of 975 breast cancer cases 65-79 years of age diagnosed from 1997-1999 and 1007 age and residence-matched controls was conducted in western Washington State. Detailed information on antidepressant use was obtained through structured in-person interviews. Logistic regression was performed to analyze the relationship between antidepressant use and breast cancer risk., Results: Overall, there was no association between ever use of antidepressants and breast cancer risk (odds ratio [OR] = 1.2, 95% confidence interval [95% CI]: 0.9-1.6). When evaluated separately, tricyclic antidepressants (TCA), selective serotonin reuptake inhibitors (SSRI), and triazolopyridines were each not associated with breast cancer risk. However, risk varied by hormone receptor status. Compared to never users, ever users of SSRIs had elevated risks of progesterone receptor (PR) negative and estrogen receptor (ER) positive/PR-negative breast cancers (OR = 1.8, 95% CI: 1.1-3.6 and OR = 2.0, 95% CI: 1.1-3.8, respectively), but not of tumors with other hormone receptor profiles., Conclusions: Based on these results and those of previous studies, there is limited evidence that any type of antidepressant use is associated with breast cancer risk overall. SSRIs may elevate risks of PR- and ER+/PR- tumors, though further studies are needed to confirm these associations.
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- 2006
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675. Reducing the expression of glutathione transferase D mRNA in Drosophila melanogaster exposed to phenol and aniline.
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Ding K, Chien Y, and Chien C
- Subjects
- Animals, Cytosol metabolism, Down-Regulation, Drosophila Proteins genetics, Drosophila melanogaster enzymology, Glutathione Transferase genetics, Isoenzymes genetics, Isoenzymes metabolism, RNA, Messenger analysis, RNA, Messenger metabolism, Aniline Compounds toxicity, Carcinogens toxicity, Drosophila Proteins metabolism, Drosophila melanogaster drug effects, Glutathione Transferase metabolism, Phenol toxicity
- Abstract
Phenol and aniline are toxic to animals. The purpose of the present study was to examine the expression of glutathione transferase D mRNA in fruit flies altered by long-term exposure to phenol and aniline. Changes in the amount of mRNA were measured by a semiquantitative reverse-transcription polymerase chain reaction assay. The level of each glutathione transferase D mRNA expressed in the phenol-treated and aniline-treated strains of adult fruit flies differed after chemical treatment. Aniline was more potent than phenol in suppressing the expression of cytosolic glutathione transferase D mRNA. Aniline reduced the level of glutathione transferase mRNA expressed in the aniline-treated strain to less than a 0.5 fraction as compared to that measured in the wild-type strain. But phenol was only able to suppress the GstD7 and GstD4 mRNAs expressed in the phenol-treated strain. Neither aniline nor phenol reduced the expression of microsomal glutathione transferase mRNA in fruit flies., ((c) 2005 Wiley Periodicals, Inc.)
- Published
- 2005
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676. Differences in colorectal carcinoma stage and survival by race and ethnicity.
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Chien C, Morimoto LM, Tom J, and Li CI
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- Aged, Colorectal Neoplasms therapy, Female, Humans, Male, Middle Aged, Neoplasm Staging, Registries, SEER Program, Survival Rate, United States epidemiology, Black or African American statistics & numerical data, Asian statistics & numerical data, Colorectal Neoplasms ethnology, Colorectal Neoplasms mortality, Hispanic or Latino statistics & numerical data, Indians, North American statistics & numerical data, White People statistics & numerical data
- Abstract
Background: In the United States, blacks with colorectal carcinoma (CRC) presented with more advanced-stage disease and had higher mortality rates compared with non-Hispanic whites. Data regarding other races/ethnicities were limited, especially for Asian/Pacific Islander and Hispanic white subgroups., Methods: Using data from 11 population-based cancer registries that participate in the Surveillance, Epidemiology and End Results program, the authors evaluated the relation among 18 different races/ethnicities and disease stage and mortality rates among 154,103 subjects diagnosed with CRC from 1988 to 2000., Results: Compared with non-Hispanic whites, blacks, American Indians, Chinese, Filipinos, Koreans, Hawaiians, Mexicans, South/Central Americans, and Puerto Ricans were 10-60% more likely to be diagnosed with Stage III or IV CRC. Alternatively, Japanese had a 20% lower risk of advanced-stage CRC. With respect to mortality rates, blacks, American Indians, Hawaiians, and Mexicans had a 20-30% greater risk of mortality, whereas Chinese, Japanese, and Indians/Pakistanis had a 10-40 % lower risk., Conclusions: The authors observed numerous racial/ethnic disparities in the risks of advanced-stage cancer and mortality among patients with CRC, and there was considerable variation in these risks across Asian/Pacific Islander and Hispanic white subgroups. Although the etiology of these disparities was multifactorial, developing screening and treatment programs that target racial/ethnic populations with elevated risks of poor CRC outcomes may be an important means of reducing these disparities., ((c) 2005 American Cancer Society.)
- Published
- 2005
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677. Maternal fluoxetine infusion does not alter fetal endocrine and biophysical circadian rhythms in pregnant sheep.
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Morrison JL, Rurak DW, Chien C, Kennaway DJ, Gruber N, McMillen IC, and Riggs KW
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- Animals, Blood Pressure, Electrocardiography, Female, Fluoxetine administration & dosage, Heart Rate, Infusions, Intravenous, Injections, Intravenous, Maternal-Fetal Exchange, Melatonin blood, Pregnancy, Prolactin blood, Respiration, Selective Serotonin Reuptake Inhibitors administration & dosage, Sheep, Circadian Rhythm drug effects, Fluoxetine pharmacology, Pregnancy, Animal physiology, Selective Serotonin Reuptake Inhibitors pharmacology
- Abstract
Objective: Depression during pregnancy is frequently treated with the selective serotonin reuptake inhibitor (SSRI), fluoxetine (FX), commonly known as Prozac (Eli Lilly & Co, Indianapolis, IN). FX potentiates serotoninergic neurotransmission and serotonin has been implicated in the regulation of circadian rhythms. We have therefore investigated the effect of chronic administration of FX on maternal and fetal circadian rhythms in sheep., Methods: Following an initial bolus dose of 70 mg FX, an 8-day continuous infusion of FX (n = 11, 98.5 microg/kg x d) was performed. Controls (n = 13) were treated with sterile water vehicle only. Maternal and fetal plasma melatonin and prolactin concentrations were determined every 3 hours for 24 hours and then every 6 hours for 24 hours beginning on the fourth day of infusion., Results: FX treatment did not alter either the basal or circadian rhythms of either maternal or fetal plasma melatonin and prolactin concentrations. Fetal cardiovascular and behavioral state parameters were measured continuously. While the incidence of low-voltage (LV) electrocortical (ECOG) activity was significantly reduced in fetuses in the FX group, there was no effect of FX on the diurnal rhythms in fetal arterial pressure, heart rate, breathing movements, or behavioral state., Conclusion: These results show that maternal FX treatment does not result in significant alterations in maternal and fetal hormonal and behavioral circadian rhythms.
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- 2005
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678. Chronic maternal fluoxetine infusion in pregnant sheep: effects on the maternal and fetal hypothalamic-pituitary-adrenal axes.
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Morrison JL, Riggs KW, Chien C, Gruber N, McMillen IC, and Rurak DW
- Subjects
- Adrenocorticotropic Hormone blood, Animals, Antidepressive Agents, Second-Generation blood, Carbon Dioxide blood, Female, Fetus drug effects, Fluoxetine blood, Gestational Age, Hydrocortisone blood, Hypothalamo-Hypophyseal System embryology, Oxygen blood, Pituitary-Adrenal System embryology, Pregnancy, Sheep, Antidepressive Agents, Second-Generation pharmacology, Fluoxetine pharmacology, Hypothalamo-Hypophyseal System drug effects, Pituitary-Adrenal System drug effects
- Abstract
Depression during pregnancy is frequently treated with the selective serotonin reuptake inhibitor, fluoxetine (FX). FX increases serotonergic neurotransmission and serotonin plays a role in the regulation of the hypothalamic-pituitary-adrenal (HPA) axis. We have therefore investigated the effect of chronic administration of FX to the pregnant ewe on the maternal and fetal HPA axes. Nineteen late-gestation sheep were surgically prepared for chronic study of the fetus. FX (n = 7, 98.5 microg/kg/d) or sterile water (control, n = 8) was administered to the ewe for 8 d by constant rate i.v. infusion with an initial FX bolus dose of 70 mg. Maternal and fetal plasma ACTH and cortisol concentrations were determined at 0700 h each day. Maternal plasma ACTH concentrations fell on infusion d 2, but no changes were observed in maternal plasma cortisol concentrations. Fetal plasma ACTH concentrations increased on infusion d 7, and fetal plasma cortisol concentrations increased on infusion d 6, 7, and 8 in the FX group. In addition, the regression coefficient for the relationship between fetal ACTH and cortisol levels was significantly greater in the FX group compared with the control group. Thus, maternal FX treatment increased fetal plasma cortisol concentration. These results are of particular interest in the context that exposure of the fetus to excess glucocorticoids at critical windows during development has been shown to increase the risk of poor health outcomes in later life.
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- 2004
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679. Managing innovation: university-industry partnerships and the licensing of the Harvard mouse.
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Blaug S, Chien C, and Shuster MJ
- Subjects
- Animals, Animals, Genetically Modified, Financing, Government, Mice, Mice, Transgenic, National Institutes of Health (U.S.), Oncogenes genetics, Research Support as Topic, United States, Cooperative Behavior, Industry, Patents as Topic, Technology Transfer, Universities
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- 2004
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680. Short-term use of umbilical artery catheters may not be associated with increased risk for thrombosis.
- Author
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Coleman MM, Spear ML, Finkelstein M, Leef KH, Pearlman SA, Chien C, Taylor SM, and McKenzie SE
- Subjects
- Antithrombin III analysis, Cerebral Hemorrhage, Female, Humans, Infant, Newborn, Infant, Premature, Infant, Premature, Diseases diagnostic imaging, Male, Peptide Fragments analysis, Peptide Hydrolases analysis, Platelet Count, Prospective Studies, Prothrombin analysis, Risk Factors, Thrombosis diagnostic imaging, Ultrasonography, Doppler, Umbilical Arteries diagnostic imaging, Catheterization, Peripheral adverse effects, Catheters, Indwelling adverse effects, Infant, Premature, Diseases etiology, Thrombosis etiology
- Abstract
Objective: Umbilical arterial catheters (UACs) have rare but serious complications related to thrombus formation. Two specific serum markers of thrombogenesis--prothrombin fragment (F1.2) and thrombin-antithrombin (TAT)--can be assayed and correlated with abdominal ultrasound visualization of UAC thrombosis. Levels of these markers of thrombogenesis have not been studied in infants with UACs. The objective of this study was to determine F1.2 and TAT levels longitudinally and compare the levels with platelet counts and ultrasound evidence of thrombi during the first week of life in infants with UACs., Methods: This study was conducted as a prospective, nonblinded, observational study performed between June 2001 and January 2002 at Christiana Care Hospital, a level III neonatal intensive care unit. Infants with a UAC in place in the first 24 hours of life were studied. All received equal amounts of heparin in the UAC. F1.2, TAT, platelet counts, and abdominal aorta ultrasounds were examined every other day starting within 24 hours of life. Studies were not done when the UAC was removed within the 5-day study period. Enzyme-linked immunosorbent assay for TAT and F1.2 was performed using a commercially available kit from Enzyngost. Data were analyzed with repeated measures analysis of variance evaluating TAT, F1.2, and platelet count over time., Results: Thirty-three patients were investigated (mean +/- standard deviation; gestational age: 27.4 +/- 3.5 weeks; birth weight: 1139 +/- 729 g). A total of 66 measurements of TAT, F1.2, and platelet counts were obtained. Sixty-one abdominal ultrasounds were performed; only 1 study was positive for UAC thrombus. There was no significant difference between F1.2 and TAT over time during the study period. Platelet counts seemed to fall over the 5-day study period, although this decrease did not reach statistical significance., Conclusion: Indwelling UACs in sick infants may not carry an increased risk of thrombosis during the first 5 days of use.
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- 2004
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681. Staminane- and isopimarane-type diterpenes from Orthosiphon stamineus of Taiwan and their nitric oxide inhibitory activity.
- Author
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Nguyen MT, Awale S, Tezuka Y, Chien-Hsiung C, and Kadota S
- Subjects
- Abietanes chemistry, Abietanes pharmacology, Cells, Cultured, Diterpenes chemistry, Diterpenes pharmacology, Inhibitory Concentration 50, Macrophages drug effects, Molecular Structure, Taiwan, omega-N-Methylarginine pharmacology, Abietanes isolation & purification, Diterpenes isolation & purification, Nitric Oxide antagonists & inhibitors, Orthosiphon chemistry, Plants, Medicinal chemistry
- Abstract
From the MeOH extract of Taiwanese Orthosiphon stamineus, two new staminane-type diterpenes, staminols C (1) and D (2), and three new isopimarane-type diterpenes, orthosiphonone C (3) and D (4) and 14-deoxo-14-O-acetylorthosiphol Y (5), have been isolated together with 16 known diterpenes, orthosiphols A, B, D, K, M, N, O, X, and Y, nororthosiphonolide A, neoorthosiphol B, orthosiphonone A, secoorthosiphols B and C, 3-O-deacetylorthosiphol I, and 2-O-deacetylorthosiphol J. Their structures were determined on the basis of the spectroscopic data. All the newly isolated diterpenes exhibited dose-dependent inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated macrophage-like J774.1 cells, and 2-O-deacetylorthosiphonone A showed the most potent activity, with an IC(50) value of 35.0 microM, comparable to that of the positive control N(G)-monomethyl-L-arginine (L-NMMA; IC(50), 35.7 microM).
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- 2004
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682. Dynamic evaluation of [18F]-FDG uptake in the rat brain by microPET imaging.
- Author
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Chen YY, Chien C, Lee TW, Fu YK, Kuo TS, and Jaw FS
- Abstract
This study aims to acquire the functional image of the rat brain, small animal positron emission tomography (microPET) with high resolution and sensitivity is adopted to assess the metabolic activity corresponding to the neuronal activity induced by the electrical stimulation of the rat tail using [18F] fluorodeoxyglucose (FDG) as the radiotracer. The microPET imaging technology can provide anatomical and functional information on neuronal activity used to analyze responses in pathway sequence relationships between the thalamus and the cerebral cortex.
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- 2004
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683. PU.1 supports proliferation of immature erythroid progenitors.
- Author
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Fisher RC, Slayton WB, Chien C, Guthrie SM, Bray C, and Scott EW
- Subjects
- Animals, Biomarkers analysis, Cell Division, Cells, Cultured, DNA-Binding Proteins metabolism, Embryo, Mammalian immunology, Embryo, Mammalian metabolism, Erythroid Precursor Cells immunology, Erythroid Precursor Cells metabolism, Gene Expression Profiling, Granulocyte-Macrophage Colony-Stimulating Factor metabolism, Green Fluorescent Proteins, Interleukin-3 metabolism, Intracellular Signaling Peptides and Proteins, Luminescent Proteins metabolism, Mice, Mice, Knockout, Oligonucleotide Array Sequence Analysis, Protein Tyrosine Phosphatase, Non-Receptor Type 6, Protein Tyrosine Phosphatases metabolism, Proto-Oncogene Proteins genetics, Receptors, Erythropoietin, Recombinant Fusion Proteins metabolism, STAT5 Transcription Factor, Stem Cell Factor metabolism, Thrombopoietin metabolism, Trans-Activators genetics, Embryo, Mammalian cytology, Erythroid Precursor Cells cytology, Erythropoiesis physiology, Erythropoietin metabolism, Milk Proteins, Proto-Oncogene Proteins metabolism, Trans-Activators metabolism
- Abstract
Despite normal levels of erythropoiesis in PU.1(-/-) embryos, PU.1(-/-) fetal hematopoietic progenitors are unable to establish sustained erythropoiesis in the adult bone marrow. This study demonstrates that PU.1(-/-) fetal erythroid progenitors are synergistically expanded by TPO plus SCF, but not combinations of EPO plus SCF, IL-3 or GM-CSF. The EPO defect is not corrected by a constitutively active variant of EPOR. Microarray analysis identified several candidate PU.1 target genes known to affect cytokine signaling and gene regulation in the erythroid lineage. These data suggest that PU.1 plays an important role in regulating the proliferation of immature erythroid progenitors.
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- 2004
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684. Paresthesias developing in an elderly patient after chronic usage of nitrofurantoin and vitamin B6.
- Author
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Lacerna RA and Chien C
- Subjects
- Aged, Drug Interactions, Female, Humans, Urinary Tract Infections drug therapy, Anti-Infective Agents, Urinary adverse effects, Nitrofurantoin adverse effects, Paresthesia chemically induced, Vitamin B 6 adverse effects
- Published
- 2003
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685. Induction of glutathione S-transferases activities in Drosophila melanogaster exposed to phenol.
- Author
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Shen S, Chien Y, and Chien C
- Subjects
- Animals, Base Sequence, Benzene toxicity, Chromatography, Affinity, Dose-Response Relationship, Drug, Drosophila melanogaster genetics, Enzyme Induction drug effects, Glutathione Transferase genetics, Glutathione Transferase isolation & purification, Glutathione Transferase metabolism, Molecular Sequence Data, Phenol chemistry, Phenol toxicity, RNA, Messenger biosynthesis, RNA, Messenger genetics, Reverse Transcriptase Polymerase Chain Reaction, Sequence Homology, Nucleic Acid, Drosophila melanogaster drug effects, Drosophila melanogaster enzymology, Glutathione Transferase biosynthesis, Phenol pharmacology
- Abstract
Studying the toxic effects of long-term exposing fruit flies to phenol is the object of this study. The induction of the glutathione S-transferases enzymatic activities, the change in the amount of mRNA related to phenol exposure, the change in survival rate of adult fruit flies, and the chemical interaction between phenol and benzene were the problems to be investigated. Glutathione S-transferases were separated by affinity chromatography and the mRNAs levels were quantified by reverse-transcription polymerase chain reaction. Long-term feeding phenol to wild type fruit flies had caused some toxic effects included increasing the resistance to phenol toxicity, lowering the benzene toxicity, and induction of glutathione S-transferases enzymatic activities. But no significant change in the amount of glutathione S-transferases GstD1 and GstD5 mRNAs had occurred. From these results, we concluded that fruit flies could develop resistance to phenol by decreasing its toxicity; phenol was a inducer of glutathione S-transferases; phenol could increase the glutathione S-transferases enzymatic activities by increasing the amount of proteins; phenol exposure could decrease the benzene toxicity; no new glutathione S-transferase isozyme subunit was induced; and the level of GstD1 and GstD5 mRNAs did not significantly increase in phenol-treated strain., (Copyright 2003 Wiley-Liss, Inc.)
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- 2003
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686. Unintentional ingestion of over the counter medications in children less than 5 years old.
- Author
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Chien C, Marriott JL, Ashby K, and Ozanne-Smith J
- Subjects
- Age Distribution, Child, Preschool, Female, Hospitalization statistics & numerical data, Humans, Infant, Male, Victoria epidemiology, Nonprescription Drugs, Poisoning epidemiology
- Abstract
Objective: Childhood ingestion of medications remains a substantial problem. Medication available over the counter (OTC) is widely used and has significant toxicity. The present study aims to investigate the nature and extent of unintentional ingestion of OTC medication in children < 5 years old in Victoria, Australia, during the period 1996-2000, in order to highlight critical factors., Methods: Numbers of enquiries relating to unintentional ingestion of OTC medication in children < 5 years old and medication types were obtained from the Victorian Poisons Information Centre for 1998-2000. Emergency Department presentations involving poisoning of children < 5 years old, the medication types and subsequent admissions were obtained from the Victorian Emergency Minimum Dataset for 1996-2000., Results: Numbers of enquiries and Emergency Department attendances for poisoning were substantially higher for OTC medication than for prescription medication; however, a lower proportion of cases involving ingestion of OTC medication (24.8%) required hospital admission during the study period compared with cases involving ingestion of prescription medications (33.8%). Overall, the peak incidence was at 2 years of age, with a slight male over-representation. Paracetamol and cough/cold preparations were the most common agents., Conclusions: The causes of unintentional ingestion of OTC medications by children might include lack of child-resistant closure (CRC), inadequate design of CRC, attitudes concerning the toxicity of OTC medications, or lack of vigilance by parents and carers in the storage and administration of OTC medications. Consideration should be given to restricting sales of toxic OTC medications to pharmacies, and increasing counselling of consumers concerning the toxicity and safe storage of OTC medications and the correct usage of CRC. The adequacy of CRC design and OTC medications warranting CRC should be reviewed by the relevant authorities.
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- 2003
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687. Risk of hepatocellular carcinoma and habits of alcohol drinking, betel quid chewing and cigarette smoking: a cohort of 2416 HBsAg-seropositive and 9421 HBsAg-seronegative male residents in Taiwan.
- Author
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Wang LY, You SL, Lu SN, Ho HC, Wu MH, Sun CA, Yang HI, and Chien-Jen C
- Subjects
- Adult, Aged, Carcinoma, Hepatocellular ethnology, Cohort Studies, Humans, Liver Neoplasms ethnology, Male, Mastication, Middle Aged, Risk Factors, Taiwan epidemiology, Taiwan ethnology, Alcohol Drinking adverse effects, Areca adverse effects, Carcinoma, Hepatocellular epidemiology, Carcinoma, Hepatocellular etiology, Hepatitis B, Chronic complications, Liver Neoplasms epidemiology, Liver Neoplasms etiology, Smoking adverse effects
- Abstract
Objectives: Hepatitis B virus (HBV) is a major cause of hepatocellular carcinoma (HCC) in the world. The specific aim of this study is to assess the associations between the risk of HCC and habits of alcohol drinking, betel quid chewing and cigarette smoking among subjects with and without chronic HBV infection., Methods: A total of 11,837 male residents in Taiwan were recruited in this community-based cohort study. Hepatitis B surface antigen (HBsAg) and antibody against hepatitis C virus (anti-HCV) in serum were determined by enzyme immunoassay, and the habits of alcohol drinking, betel quid chewing and cigarette smoking were collected through standardized personal interview according to a structured questionnaire. During the follow-up period of 91,885 person-years, 115 incident HCC cases were identified through data linkage with national cancer registry profile. The relative risk (RR) of developing HCC for habits of various substance use and chronic HBV infection were estimated by Cox's proportional hazards regression analyses., Results: Significantly increased HCC risk was observed for seropositives of HBsAg or anti-HCV, alcohol drinkers, betel quid chewers and cigarette smokers. There was a significant dose-response relationship between the risk of HCC and the number of habits of substance use. The highest multivariate-adjusted HCC risk was observed among HBsAg-seropositive substance users (RRs: 17.9-26.9), followed by HBsAg-seropositive non-users (RRs: 13.1-19.2), HBsAg-seronegative substance users (RRs: 1.6-2.7) and HBsAg-seronegative non-users (referent with RR = 1). The multivariate-adjusted relative HCC risks for habits of use of various substances were more profound among HBsAg-seronegatives than HBsAg-seropositive ones., Conclusion: Habitual alcohol drinking, betel quid chewing and cigarette smoking are associated with an increased risk of HCC. Abstinence from substance use is important for the prevention of HCC in areas where chronic HBV infection is endemic.
- Published
- 2003
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688. Effect of maternal fluoxetine administration on uterine blood flow, fetal blood gas status, and growth.
- Author
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Morrison JL, Chien C, Riggs KW, Gruber N, and Rurak D
- Subjects
- Acid-Base Equilibrium, Animals, Antidepressive Agents, Second-Generation administration & dosage, Antidepressive Agents, Second-Generation therapeutic use, Blood Gas Analysis, Blood Glucose metabolism, Blood Pressure, Depression drug therapy, Female, Fetus physiology, Fluoxetine administration & dosage, Fluoxetine therapeutic use, Heart Rate, Humans, Lactic Acid blood, Pregnancy, Pregnancy Complications drug therapy, Pregnancy Outcome, Regional Blood Flow drug effects, Selective Serotonin Reuptake Inhibitors administration & dosage, Selective Serotonin Reuptake Inhibitors pharmacology, Selective Serotonin Reuptake Inhibitors therapeutic use, Sheep, Antidepressive Agents, Second-Generation pharmacology, Embryonic and Fetal Development drug effects, Fetus drug effects, Fluoxetine pharmacology, Uterus blood supply
- Abstract
Clinical depression, diagnosed in 5-15% of women during pregnancy, increases the risk of negative pregnancy outcomes including an increased incidence of low birth weight newborns and preterm delivery. Fluoxetine, a selective serotonin reuptake inhibitor, is often prescribed to treat depression due to its efficacy, high margin of safety, and mild side effects. However, fluoxetine initially increases plasma serotonin concentration, and serotonin causes uterine vasoconstriction in sheep, which could result in fetal hypoxemia. To assess fetal fluoxetine effects, late-gestation pregnant sheep were surgically prepared for the measurement of blood gases, heart rate, blood pressure, and uterine artery blood flow (n = 29). Ewes received a 70-mg bolus i.v. infusion of fluoxetine over 2 min in 10 mL of sterile water followed by continuous infusion at a rate of 100 microg/min for 8 d (n = 14), or continuous infusion of sterile water (n = 15). Transient decreases in uterine artery blood flow, fetal PO(2), and oxygen saturation were observed within the first 15 min after fluoxetine exposure, which did not return to normal values by 24 h. Fetal pH decreased and PCO(2) increased over the first 4 h with a return to normal by 24 h. However, there were no differences in uterine artery blood flow, blood gas status, or cardiovascular measures between the control and fluoxetine group over the rest of the 8-d infusion period. Thus, fluoxetine exposure during pregnancy has transient effects on fetal status that may be of developmental consequence if they occur repetitively.
- Published
- 2002
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689. Fetal behavioural state changes following maternal fluoxetine infusion in sheep.
- Author
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Morrison JL, Chien C, Gruber N, Rurak D, and Riggs W
- Subjects
- Animals, Antidepressive Agents, Second-Generation blood, Behavior, Animal drug effects, Carbon Dioxide blood, Electrooculography drug effects, Eye Movements drug effects, Female, Fluoxetine blood, Oxygen blood, Pregnancy, Pregnancy Outcome, Respiration drug effects, Sheep, Sleep drug effects, Uterus blood supply, Antidepressive Agents, Second-Generation pharmacology, Fetus drug effects, Fluoxetine pharmacology
- Abstract
Clinical depression is diagnosed in 5-15% of women during pregnancy, increasing the risk of negative outcomes. Fluoxetine (FX), a selective serotonin reuptake inhibitor, is prescribed during pregnancy. In adults, FX alters sleep patterns with single doses decreasing total sleep time and rapid eye movement sleep. The effects of FX on sleep in the fetus are unknown. However, 5-hydroxytryptophan, the precursor of serotonin, has been reported to prolong high-voltage (HV) electrocortical (ECoG) activity and increase the incidence of fetal breathing movements (FBM) in the sheep fetus. We hypothesize that FX exposure will decrease the incidence of LV ECoG in the fetus. Twenty-one pregnant sheep were surgically prepared for chronic study of blood gases, ECoG activity, eye movements and FBM. After 3 days of recovery, ewes received a 70-mg bolus i.v. infusion of FX or sterile water followed by continuous infusion at a rate of 0.036 mg/min for 8 days. The incidence of low-voltage (LV) ECoG decreased from 54+/-4% on the preinfusion day to 45+/-5% on infusion day 1 in the FX group and remained decreased throughout the infusion period. In addition, the incidence of both eye movements and FBM was decreased on infusion day 1 compared to preinfusion day in the FX group. HV ECoG increased from 39+/-3% on preinfusion day to 68+/-14% on FX infusion day 1 and remained elevated throughout the infusion period. These data show that maternal FX administration alters fetal behavioural state.
- Published
- 2001
- Full Text
- View/download PDF
690. Mechanisms of bradykinin-mediated Ca(2+) signalling in canine cultured corneal epithelial cells.
- Author
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Huang SC, Chien C, Hsiao L, Wang C, Chiu C, Liang K, and Yang C
- Subjects
- Animals, Calcium metabolism, Calcium Channel Blockers pharmacology, Cells, Cultured, Cholera Toxin pharmacology, Dogs, Enzyme Inhibitors pharmacology, Estrenes pharmacology, Imidazoles pharmacology, Pertussis Toxin, Pyrrolidinones pharmacology, Thapsigargin pharmacology, Type C Phospholipases antagonists & inhibitors, Virulence Factors, Bordetella pharmacology, Bradykinin pharmacology, Calcium Signaling, Epithelium, Corneal metabolism
- Abstract
Experiments were designed to differentiate the mechanisms of bradykinin receptors mediating the changes in intracellular Ca(2+) concentration ([Ca(2+)](i)) in canine cultured corneal epithelial cells (CECs). Bradykinin and Lys-bradykinin caused an initial transient peak of [Ca(2+)](i) in a concentration-dependent manner, with half-maximal stimulation (pEC(50)) obtained at 6.9 and 7.1, respectively. Pretreatment of CECs with pertussis toxin (PTX) or cholera toxin (CTX) for 24 h did not affect the bradykinin-induced [Ca(2+)](i) changes. Application of Ca(2+) channel blockers, diltiazem and Ni(2+), inhibited the bradykinin-induced Ca(2+) mobilization, indicating that Ca(2+) influx was required for the bradykinin-induced responses. Addition of thapsigargin (TG), which is known to deplete intracellular Ca(2+) stores, transiently increased [Ca(2+)](i) in Ca(2+)-free buffer, and subsequently induced Ca(2+) influx when Ca(2+) was readded to this buffer. Pretreatment of CECs with TG completely abolished bradykinin-induced initial transient [Ca(2+)](i), but had slight effect on bradykinin-induced Ca(2+) influx. Pretreatment of CECs with 1-[beta-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl]-1H-imidazole (SKF96365) and 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122) inhibited the bradykinin-induced Ca(2+) release and Ca(2+) influx, consistent with the inhibition of receptor-gated Ca(2+) channels and phospholipase C (PLC) in CECs, respectively. These results demonstrate that bradykinin directly stimulates B(2) receptors and subsequently Ca(2+) mobilization via a PTX-insensitive G protein in canine CECs. These results suggest that bradykinin-induced Ca(2+) influx into the cells is not due to depletion of these Ca(2+) stores, as prior depletion of these pools by TG has no effect on the bradykinin-induced Ca(2+) influx that is dependent on extracellular Ca(2+) in CECs.
- Published
- 2001
- Full Text
- View/download PDF
691. A preliminary study on comparison and fusion of metabolic images of PET with anatomic images of CT and MRI.
- Author
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Zhu Z and Chien C
- Subjects
- Carcinoma, Squamous Cell diagnosis, Carcinoma, Squamous Cell metabolism, Follow-Up Studies, Humans, Image Processing, Computer-Assisted, Epilepsy diagnosis, Epilepsy metabolism, Lung Neoplasms diagnosis, Lung Neoplasms metabolism, Magnetic Resonance Imaging, Tomography, Emission-Computed, Tomography, X-Ray Computed
- Abstract
Objective: To compare and match metabolic images of PET with anatomic images of CT and MRI., Methods: The CT or MRI images of the patients were obtained through a photo scanner, andthen transferred to the remote workstation of PET scanner with a floppy disk. A fusion method was developed to match the 2-dimensional CT or MRI slices with the correlative slices of 3-dimensional volume PET images., Results: Twenty-nine metabolically changed foci were accurately localized in 21 epilepsy patients' MRI images, while MRI alone had only 6 true positive findings. In 53 cancer or suspicious cancer patients, 53 positive lesions detected by PET were compared and matched with the corresponding lesions in CT or MRI images, in which 10 lesions were missed. On the other hand, 23 lesions detected from the patients' CT or MRI images were negative or with low uptake in the PET images, and they were finally proved as benign., Conclusions: Comparing and matching metabolic images with anatomic images helped obtain a full understanding about the lesion and its peripheral structures. The fusion method was simple, practical and useful for localizing metabolically changed lesions.
- Published
- 2001
692. Morphological, immunohistochemical and quantitative studies of murine brain mast cells after mating.
- Author
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Yang M, Chien C, and Lu K
- Subjects
- Animals, Cell Count, Cell Size, Female, Gonadotropin-Releasing Hormone physiology, Male, Mast Cells cytology, Mice, Mice, Inbred ICR, Microscopy, Electron, Neuroimmunomodulation physiology, Neurosecretory Systems cytology, Neurosecretory Systems physiology, Copulation physiology, Mast Cells chemistry, Mast Cells physiology, Thalamus cytology
- Abstract
The mast cell is one of the immune cells, and can be triggered behaviorally to increase in the CNS of the sexually active dove. In the present study, we used ICR mice to investigate the number of brain mast cells in mated (one male with three female mice), non-mated (housed with female mice, but no mating) and control (four male mice housed together in one cage) male mice. We found that at least 40% of mated male mice had significant more mast cells than the maximum value seen in the controls, and that a significant correlation existed between the distribution index of mast cells and the postcoitum date. These mast cells were especially numerous in the thalamus and velum interpositum (VIP). Morphological observations showed that the increased mast cells were ultrastructurally similar to those in the controls, and displayed gonadotropin-releasing hormone (GnRH)-like immunoreactivity. Based on the facts that the number of brain mast cells in the male mice increased significantly after mating and that the change in the distribution of mast cells in the VIP and the thalamic parenchyma correlated well with time postcoitum, we speculate that, after mating, mast cells may migrate from the VIP to the thalamic parenchyma along the vascular tree of the brain. These results strongly suggest that mast cells are involved in the interaction among the immune, endocrine, and nervous systems in the mated male mouse brain.
- Published
- 1999
- Full Text
- View/download PDF
693. Taurine-sulfur assimilation and taurine-pyruvate aminotransferase activity in anaerobic bacteria.
- Author
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Chien C, Leadbetter ER, and Godchaux W
- Abstract
We demonstrated the ability of strictly fermentative, as well as facultatively fermentative, bacteria to assimilate sulfonate sulfur for growth. Taurine (2-aminoethanesulfonate) can be utilized by Clostridium pasteurianum C1 but does not support fermentative growth of two Klebsiella spp. and two different Clostridium spp. However, the latter are able to assimilate the sulfur of a variety of other sulfonates (e.g., cysteate, 3-sulfopyruvate, and 3-sulfolactate) anaerobically. A novel taurine-pyruvate aminotransferase activity was detected in cell extracts of C. pasteurianum C1 grown with taurine as the sole sulfur source. This activity was not detected in extracts of other bacteria examined, in C. pasteurianum C1 grown with sulfate or sulfite as the sulfur source, or in a Klebsiella isolate assimilating taurine-sulfur by aerobic respiration. More common aminotransferase activities (e.g., with aspartate or glutamate as the amino donor and pyruvate, oxalacetate, or (alpha)-ketoglutarate as the amino acceptor) were present, no matter what sulfur source was used for growth. Partial characterization of the taurine-pyruvate aminotransferase revealed an optimal temperature of 37(deg)C and a broad optimal pH range of 7.5 to 9.5.
- Published
- 1997
- Full Text
- View/download PDF
694. Automated analysis of protein NMR assignments using methods from artificial intelligence.
- Author
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Zimmerman DE, Kulikowski CA, Huang Y, Feng W, Tashiro M, Shimotakahara S, Chien C, Powers R, and Montelione GT
- Subjects
- Automation, Expert Systems, Magnetic Resonance Spectroscopy methods, Protein Conformation
- Abstract
An expert system for determining resonance assignments from NMR spectra of proteins is described. Given the amino acid sequence, a two-dimensional 15N-1H heteronuclear correlation spectrum and seven to eight three-dimensional triple-resonance NMR spectra for seven proteins, AUTOASSIGN obtained an average of 98% of sequence-specific spin-system assignments with an error rate of less than 0.5%. Execution times on a Sparc 10 workstation varied from 16 seconds for smaller proteins with simple spectra to one to nine minutes for medium size proteins exhibiting numerous extra spin systems attributed to conformational isomerization. AUTOASSIGN combines symbolic constraint satisfaction methods with a domain-specific knowledge base to exploit the logical structure of the sequential assignment problem, the specific features of the various NMR experiments, and the expected chemical shift frequencies of different amino acids. The current implementation specializes in the analysis of data derived from the most sensitive of the currently available triple-resonance experiments. Potential extensions of the system for analysis of additional types of protein NMR data are also discussed.
- Published
- 1997
- Full Text
- View/download PDF
695. Nonmonotonic superconducting transitions in mesoscopic Al structures induced by radio-frequency radiation.
- Author
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Strunk C, Bruyndoncx V V, Van Haesendonck C, Moshchalkov VV, Bruynseraede Y, Burk B, Chien C, and Chandrasekhar V V
- Published
- 1996
- Full Text
- View/download PDF
696. Control of bright picosecond X-ray emission from intense subpicosecond laser-plasma interactions.
- Author
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Workman J, Maksimchuk A, Liu X, Ellenberger U, Coe JS, Chien C, and Umstadter D
- Published
- 1995
- Full Text
- View/download PDF
697. Separation of multiple forms of acidic glutathione S-transferase isozymes in a susceptible and a resistant strain of house fly, Musca domestica (L.).
- Author
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Chien C, Motoyama N, and Dauterman WC
- Subjects
- Animals, Chromatography, Affinity, Glutathione Transferase metabolism, Insecticide Resistance, Isoenzymes metabolism, Kinetics, Glutathione Transferase isolation & purification, Houseflies enzymology, Isoenzymes isolation & purification
- Abstract
The acidic glutathione S-transferases from a CSMA (susceptible) strain and a Cornell-R (resistant) strain of houseflies were purified and separated utilizing affinity chromatography followed by chromatofocusing. Nine fractions were isolated from each house fly strain. Fraction 1 had the highest 1-chloro-2,4-dinitrobenzene vs. 1,2-dichloro-4-nitrobenzene ratio (CDNB/DCNB ratio) in both strains and the ratio of all the other fractions tended to decrease as the isoelectrical points decreased except for fractions 4 and 9. Most fractions from the CSMA strain had higher CDNB conjugation activities than the fractions from the Cornell-R strain, but all the fractions from the CSMA strain had lower DCNB conjugation activities than fractions from the Cornell-R strain. Steady-state kinetics of all the fractions were examined. The Km values obtained from both strains ranged from 0.36 to 1.12 mM, while the Vmax value ranged from 3.0 to 32.6 mumol/min/mg. In the 100,000 g supernatant, the CDNB specific activities in the CSMA strain was about 1/3 of the activity in the Cornell-R strain but it was about 1.5-fold following affinity chromatography. The specific activity for DCNB measured in the CSMA strain was only 1/5 of the activities of the Cornell-R strain in the 100,000 g supernatant, but was about the same after affinity chromatography. The difference was due to the selectivity of the affinity column used in the current study.
- Published
- 1995
- Full Text
- View/download PDF
698. Immunological comparison of cytosolic glutathione S-transferases between rat and two strains of houseflies.
- Author
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Chien C, Motoyama N, and Dauterman WC
- Subjects
- Animals, Blotting, Western, Cross Reactions, Cytosol enzymology, Electrophoresis, Polyacrylamide Gel, Glutathione Transferase chemistry, Glutathione Transferase metabolism, Isoenzymes immunology, Male, Rats, Glutathione Transferase immunology, Houseflies enzymology, Liver enzymology
- Abstract
Five different antisera, which include three antisera raised against rat liver glutathione S-transferases (GST), one antiserum raised against human pi GST, and one antiserum raised against housefly GST1, were used to examine their cross-reactivity with different classes of GST subunits isolated from rat liver and the housefly. Two classes of rat liver GSTs, alpha and mu, were isolated from rat liver and two classes of housefly GSTs, GST1 and GST2, were isolated from both CSMA and Cornell-R strains. Antiserum against GST 3-3 was the most reactive antiserum and reacted not only with the mu class of GSTs but also with the GST1 class from both CSMA and Cornell-R strains. Antiserum against human pi GST and antiserum against housefly GST1 had weak immunological reactivity toward the GST1 class from both strains of housefly. Antiserum against GST 4-4 and antiserum against GST 1-1 had no immunological reactivity toward any class of GSTs from housefly. None of the five antisera had any immunological cross-reactivity toward subunit 2 of the alpha class of rat GST and the GST2 class of housefly GSTs from both strains.
- Published
- 1994
- Full Text
- View/download PDF
699. Exclusive production of K+K- pi + pi - in photon-photon collisions.
- Author
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Aihara H, Alston-Garnjost M, Armitage JC, Bakken JA, Barbaro-Galtieri A, Barker AR, Barnes AV, Barnett BA, Bengtsson H, Bintinger DL, Blumenfeld BJ, Bobbink GJ, Bross AD, Buchanan CD, Buijs A, Cain MP, Caldwell DO, Chamberlain O, Chien C, Clark AR, Cordier A, Dahl OI, Day CT, Derby KA, van Driel MA, Eberhard PH, Eisner AM, Erné FC, Fancher DL, Fujii H, Fujii T, Gabioud B, Gary JW, Gorn W, Hadley NJ, Hauptman JM, Hofmann W, Huth JE, Hylen J, Joshi UP, Kamae T, Kaye HS, Kees KH, Kenney RW, Kerth LT, Ko W, Koda RI, Kofler RR, Kwong KK, Lander RL, Langeveld WG, Layter JG, Linde FL, Lindsey CS, Loken SC, Lu A, Lu X, Lynch GR, Madansky L, Madaras RJ, Maeshima K, Magnuson BD, Marx JN, and Maruyama K
- Published
- 1985
- Full Text
- View/download PDF
700. Bone morphogenesis in implants of insoluble bone gelatin.
- Author
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Urist MR, Iwata H, Ceccotti PL, Dorfman RL, Boyd SD, McDowell RM, and Chien C
- Subjects
- Animals, Bone Matrix metabolism, Bone Matrix transplantation, Bone and Bones analysis, Chlorides, Edetic Acid, Hot Temperature, Hydrolysis, Lithium, Microbial Collagenase metabolism, Muscles, Pepsin A metabolism, Protein Denaturation, Rats, Sodium Hydroxide, Solubility, Transplantation, Homologous, Water, Gelatin isolation & purification, Gelatin metabolism, Morphogenesis, Osteogenesis
- Abstract
Insoluble bone gelatin with inclusions of insoluble noncollagenous protein produces new bone when implanted in muscle in allogeneic rats. The implanted residue provides the milieu for expression of bone morphogenetic potential of migratory mesenchymal cells. Neutral buffer solutions activate endogenous enzymes that degrade components essential for cell interactions and differentiation of bone. Chloroform-methanol either denatures or extracts constituents responsible for degradation. Insoluble bone gelatin produces new bone after extraction at 2 degrees with neutral salts, 0.5 M EDTA, 0.1 M Tris.HCl, 4 M urea, 0.5 M hydroxylamine, and 10 M KCNS, as well as after limited digestion with pepsin or collagenase, but not after extraction with 5 M guanidine, 7 M urea, water saturated with phenol, or after alkali hydrolysis with 0.1 N NaOH. The specific activity of cell populations interacting with insoluble bone gelatin suggests that a chemical bond between collagen and a noncollagenous protein or part of a protein, cleaved by a neutral proteinase, controls the bone morphogenetic reaction.
- Published
- 1973
- Full Text
- View/download PDF
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