Biomedical subjects

Y R Chen

Publications and source records attributed to Y R Chen.

At least 37 records · Page 2Linked to original sources

PubMed2000

Analysis of coptisine, berberine and palmatine in adulterated Chinese medicine by capillary electrophoresis-electrospray ion trap mass spectrometry.

Chinese medicine preparations contaminated with coptisine, berberine and palmatine were studied by capillary electrophoresis-electrospray ion trap mass spectrometry. The dubious adulterants were identified by their retention times, molecular ions and specific fragment ions produced from collision induced dissociation. The results showed that, in comparison with CE-UV and capillary electrophoresis-electrospray mass spectrometry (CE-ESI-MS), more reliable identification could be achieved with CE-ESI-MS-MS using ion trap mass spectrometry.

Berberine↗

PubMed2000

Butyrate-inducible elements in the human gamma-globin promoter.

OBJECTIVE: Several agents including hydroxyurea, erythropoietin and butyric acid have been shown to reactivate gamma gene expression during adult stage development by unknown molecular mechanisms. In addition to inhibiting the enzyme histone deacetylase, butyrate may modulate transcription factor binding to specific DNA sequences defined as butyrate response elements (BREs). The purpose of this study was to identify promoter sequences involved in gamma gene activation by butyrate using truncation mutants in stable cell lines. MATERIALS AND METHODS: A detailed analysis of Agamma gene activation in the presence of alpha-aminobutyric acid and sodium butyrate was completed in stable mouse erythroleukemia (MEL) cell pools established with seven Agamma promoter truncation mutants. Functional studies were performed in a transient assay system followed by gel mobility shift assays to define protein binding patterns and to demonstrate transcription factor interactions in the gamma promoter BRE. RESULTS: Agamma promoter analysis in stable MEL cell pools revealed BREs between nucleotide-141 and -201, and nucleotide-822 and -893 (gammaBRE). The gammaBRE required the minimal Agamma promoter (-201 to +36) to stimulate gene expression. We observed a 6.1-fold (p < 0.05) increase in CAT activity for the minimal Agamma promoter alone compared with an 11.5-fold (p < 0.05) increase when the gamma promoter was combined with the -822 to -893 fragment. Protein binding studies demonstrated altered protein-DNA interactions in the gammaBRE after butyrate induction. The pattern for binding observed suggest both negative- and positive-acting transcription factors may interact in this region. CONCLUSION: The data supports the -822 to -893 region as a DNA regulatory element that contributes to Agamma gene inducibility by butyrate.

Animals↗

PubMed2000

Two-dimensional visible/near-infrared correlation spectroscopy study of thermal treatment of chicken meats.

The thermal treatment of chicken meats was investigated by generalized 2D visible/NIR correlation spectroscopy. Synchronous 2D visible correlation analysis revealed that there are at least two bands around 445 and 560 nm, decreasing in intensity with cooking time. The corresponding asynchronous spectrum indicated that the spectral intensity reduction of the two bands occurs before the intensity variation of the 475, 520, and 585 nm bands. It suggested that the 445 and 560 nm bands be assigned to deoxymyoglobin and oxymyoglobin, respectively, and at least one of the 475, 520, and 585 nm bands assigned to the denatured species (metmyoglobin) of myoglobin. Also, the asynchronous 2D NIR correlation spectrum indicated that C-H fractions are easily oxidized. In addition, strong correlation peaks correlating the bands in the visible, SW-NIR, and NIR spectral regions were observed and discussed.

Animals↗

PubMed2000

Determination of sibship by PCR-amplified short tandem repeat analysis in Taiwan.

BACKGROUND: Sibship determination for any two persons whose parents have died is one of the most fundamental issues of personal identification, second only to those of a parent-child relationship. STUDY DESIGN AND METHODS: By automated fluorescence analysis of a PCR-amplified short tandem repeat (STR) system in conjunction with capillary electrophoresis, a panel of up to 15 polymorphic, autosomal, unlinked STR loci was used to investigate sibship index (SI) values in a cohort of 126 true sibling pairs. These SI values were then compared with those of 126 random pairs. RESULTS: The 15-loci STR panel provides a cumulative power of exclusion of 0. 9999997. Of the 126 random pairs, 124 (98.4%) had cumulative sibship indices (CSIs) of <1.0, and none had a CSI of >3.0 (median, 0.0101; range, 0.0000003-2.5376). In contrast, 107 (85%) of the 126 sibling pairs had a CSI of >100 (median, 5,579.9853; range, 0.0747-9,406,829, 249.8461). However, five pairs (4%) of the sibling group had a CSI of <3.0. True sibship was confirmed for this particular group by additional paternity testing and mitochondrial DNA sequence analysis. Among a total of 1890 observations (15 loci x 126 pairs), two alleles per locus were shared 760 times (40.21%) (mean, 6.03 loci; range, 1-10) in the sibling group, but only 192 times (10.16%) in the random group (mean, 1.52 loci; range, 1-5) (p<0.001). No alleles were shared 696 times (36.83%) in the unrelated pairs, as compared to 176 times (9.31%) in the sibling group (p<0.001). A polarized distribution was not noted in the sharing of single alleles in either the random or the sibling group: 1002 observations (53.02%) and 954 observations (50.48%), respectively. CONCLUSION: Highly polymorphic STR analysis can be discriminative in most sibship determinations, and the sharing of two alleles per locus is most informative in indicating sibship. Complementary mitochondrial DNA sequence analysis is mandatory in a few cases to exclude or establish true sibship when CSIs are equivocal and neither parent is available.

Alleles↗

PubMed2000

Application of endoscope in zygomatic fracture repair.

The endoscope has been used to visualise the upper face and brow in aesthetic facial surgery which is performed without a coronal incision. We applied these principles to repair zygomatic fractures with the aid of a 4 mm, 30 degree telescope inserted through a small temporal incision. Fracture sites at the zygomatic arch and the zygomaticofrontal suture were exposed and fixed with miniplates under endoscopic control. This technique was used in 15 consecutive patients including 2 with isolated zygomatic arch comminuted fractures and 13 having displaced zygomatic fractures with segmental, displaced zygomatic arch fractures. Nine patients were men and six patients were women with a mean age of 35 years. Three patients had associated mandibular fractures. The periods of follow-up ranged from 3 to 22 months. Two patients developed transient frontal nerve palsy which recovered within 2 months. One patient had mild temporal hollowing on the side of the facial fracture. All patients achieved the adequate anatomic reduction and satisfactory malar symmetry. There has been no case of chewing problems, cheek numbness or progressive enophthalmos developing postoperatively. Application of the endoscope in zygomatic fracture repair minimises the scalp scar, avoids forehead numbness, provides a comfortable postoperative recovery and shortens hospital stay. Careful preoperative evaluation and proper surgical technique are mandatory for achieving optimal results in selected patients.

Accidents, Traffic↗

PubMed2000

Economic feasibility analysis for an automated on-line poultry inspection technology.

On-line carcass inspection of chickens in the United States is currently done using visual (organoleptic) methods. Inspectors from the USDA Food Safety and Inspection Service (FSIS) inspect the viscera and carcass and, for older birds, the heads using a sequence of observations and palpations at a postmortem inspection station. The streamlined inspection system (SIS) and the new line speed inspection system (NELS) are the most prevalent visual inspection methods. The former has a line speed of 70 birds/min with two inspectors per line, and the latter has a line speed of 91 birds/min requiring three inspectors per line. Both inspection methods are labor intensive and prone to human error. In addition, the speed of the slaughter line is dictated by the number of birds per minute that can be inspected by FSIS inspectors. Ninety-one birds/min is currently the maximum visual inspection line speed allowed under current Federal regulations. This study evaluates the economic benefits of using automated inspection in place of visual inspection from the perspective of both the slaughter plant and FSIS. The results indicate that FSIS and slaughter plants would gain economic benefits by using automated inspection in place of visual inspection. The economic benefits to FSIS would accrue from labor savings, whereas the economic benefits to slaughter plants would accrue primarily from increased throughput from faster inspection line speeds.

Abattoirs↗

PubMed2000

Acute life-threatening injuries in facial fracture patients: a review of 1,025 patients.

BACKGROUND: The literature on facial fractures has emphasized obstruction of the airway as the most common associated life-threatening problem. Other life-threatening injuries associated with facial fractures are not as well documented. For this reason, we conducted a retrospective study involving 1,025 patients with facial fractures admitted to the trauma center at Chang Gung Memorial Hospital in Taiwan from January 1995 through December 1998. METHODS: This study identifies the incidence of facial fractures and establishes a management plan. Life-threatening injuries associated with facial fractures were those that warranted immediate invasive rescue procedures. RESULTS: Sixty-four (6.2%) of the patients with facial fractures required life-saving intervention; 21 patients had cerebral trauma prompting craniotomy, 19 had hemorrhagic shock, 17 had airway compromise, and 7 had pulmonary injury grave enough to necessitate tube thoracostomy. There were five mortalities, three due to cerebral trauma and two credited to hemorrhagic shock not identified until long after admission. CONCLUSION: These findings illustrate the need for prompt identification and proper management of the associated life-threatening injuries in facial fracture patients. Clinical assessment should begin with evaluation of cerebral trauma, followed by hemorrhagic shock, airway compromise, and hemopneumothorax. Proper management may require a multidisciplinary and coordinated team approach.

Acute Disease↗

PubMed2000

Interdental distraction osteogenesis and rapid orthodontic tooth movement: a novel approach to approximate a wide alveolar cleft or bony defect.

The closure of a wide alveolar cleft and fistula in cleft patients and the reconstruction of a maxillary dentoalveolar defect in traumatic patients are challenging for both orthodontists and surgeons. This is due to the difficulty in achieving complete closure by using local attached gingiva and the great volume of bone required for the graft. In this article, the authors propose using interdental distraction osteogenesis to create a segment of new alveolar bone and attached gingiva for the complete approximation of a wide alveolar cleft/fistula and the reconstruction of a maxillary dentoalveolar defect. They performed this procedure on one patient with a traumatic maxillary dentoalveolar defect and 10 patients with unilateral or bilateral cleft lips and palates who had varied dentoalveolar clefts/fistulas. Interdental and maxillary osteotomies were performed on one side of the dental arch by the cleft or defect. After a latency period of 3 days, the osteotomized distal segment of the dental arch was then distracted and transported toward the cleft or defect by using a toothborne intraoral distraction device. The alveoli and gingivae on both ends of the cleft or defect were approximated after distraction osteogenesis. The need for extensive alveolar bone grafting was eliminated. A segment of new edentulous alveolus and attached gingiva was created interdentally at a site distant to the cleft or defect. In the cleft patients, teeth were moved orthodontically into the regenerate (newly formed alveolar bone) dental crowding 1 week after distraction. The orthodontic tooth movement was rapidly completed in 3 months, and the edentulous space was eliminated. Interdental distraction osteogenesis minimizes an alveolar cleft/fistula and helps reconstruct a maxillary dentoalveolar defect by approximating the native alveoli and gingivae; it also creates new alveolar bone and gingiva for rapid orthodontic tooth movement.

Alveolar Process↗

PubMed2000

The course of the inferior alveolar nerve in the normal human mandibular ramus and in patients presenting for cosmetic reduction of the mandibular angles.

This study was undertaken to quantify the path of the inferior alveolar nerve in the normal human mandible and in the mandibles of patients presenting for cosmetic reduction of the mandibular angles. The goals were: (1) to provide normative information that would assist the surgeon in avoiding injury to the nerve during surgery; (2) to characterize gender differences in the normal population; and (3) to compare the course of the nerve in the normal population to its course in a group of patients who presented with a complaint of "square face." The study was based upon the computerized tomographic scans of 10 normal patients (six men, four women) and 8 patients (all women) complaining of "square face." Using AnalyzePC 2.5 imaging software, the mandibles were segmented and the position of the nerve was recorded within its osseous canal in the mandibular ramus on each axial slice in which it was identifiable. Distances were calculated between the nerve and the anterior, posterior, lateral, and medial cortices. The positions of the lateral ramus prominence and the lowest point on the sigmoid notch were also recorded. The position of the mental foramen was recorded in relation to the nearest tooth, and the three-dimensional surface distances from the foramen to the alveolar bone, the inferior border of the mandible, and the mandibular symphysis were determined. The distances from the entrance of the nerve into the mandible to the lateral ramus prominence and the lowest point on the sigmoid notch were calculated. Summary statistics were obtained, comparing differences in gender. The nerve was identifiable in each ramus over a mean distance of 12.7 mm. On average, the lateral ramus prominence was 0.3 mm higher on the caudad-cephalad axis than the point at which the nerve entered the bone, whereas the location of the lowest point on the sigmoid notch was 16.6 mm above the nerve. The average distances from the nerve to the anterior, posterior, medial, and lateral cortices were 11.6, 12.1, 1.8, and 4.7 mm, respectively. Gender differences were significant for all of these except the medial cortex to nerve distance. On average, the mental foramen exited the body of the mandible immediately below the second premolar and the average surface distances from the foramen to the symphysis, the most cephalad alveolar bone, and the inferior border of the body were 30.9, 14.2, and 19.3 mm, respectively. With regard to the patients presenting for mandibular angle reduction, there were a few statistically significant but small scalar differences from normal controls.

Adolescent↗

PubMed2000

The effect of hamulus fracture on the outcome of palatoplasty: a preliminary report of a prospective, alternating study.

OBJECTIVE: To determine whether, in performing palatoplasty, fracture of the pterygoid hamulus is beneficial, detrimental, or neutral with respect to intraoperative and perioperative complications, hearing outcome, and speech outcome. DESIGN: Prospective, alternating. SETTING: Institutional, tertiary cleft palate center, Chang Gung Memorial Hospital, Taipei, Taiwan. PARTICIPANTS: A total of 173 patients enrolled in the study, of whom 161 had charts available for analysis. INTERVENTIONS: During the performance of palatoplasty, 85 patients received hamulus fracture and 76 patients did not. All palatoplasties were performed by the same surgeon. MAIN OUTCOME MEASURES: (1) Surgical outcomes, including patient demographic data, palatoplasty type and duration, blood loss, incidences of oronasal fistulae, temporary mucosal dehiscence, and postoperative bleeding; (2) otolaryngological outcomes, including hearing results as judged by auditory brainstem response testing, myringotomy tube data describing rates of tube extrusion, and culture results from sampled effusions; and (3) preliminary speech outcomes as described by judgments of overall velopharyngeal function from perceptual speech samples. RESULTS: No statistically significant differences in any of the measured surgical, otolaryngological, or preliminary speech outcomes were found between the groups who did and did not receive hamulus fracture. CONCLUSIONS: On the basis of these results, we are unable to advocate the performance of hamulus fracture as an operative maneuver during the performance of primary palatoplasty. The historical rationale and theoretical advantage of this maneuver have not been demonstrated here nor have any detrimental effects of the maneuver been measured.

Chi-Square Distribution↗

PubMed2000

Major hematological diseases associated with cleft lip and palate.

OBJECTIVE: Cleft lip and palate is among the most common congenital anomalies. Its association with major blood disorders has rarely been reported. The purpose of this study was to report two patients who had major blood diseases associated with cleft lip and palate. PATIENTS AND RESULTS: From June 1995 to December 1997, there were 2700 patients with cleft lip, cleft palate, or both who received treatment at Chang Gung Memorial Hospital. Two of them were found to have major hematological disorders. In both cases, the disorder was detected by preoperative blood cell counts and white cell differentiation. Case 1 was a 21-year-old woman patient with repaired right cleft lip. She was admitted for alveolar bone grafting and closure of oronasal fistula. Abnormal presentation of blast cells was found, and subsequent bone marrow study confirmed acute lymphocytic leukemia. Case 2 was a 26-year-old man with left secondary cleft lip nasal deformity scheduled to receive staged reconstructive operations. An elevated platelet count was found and subsequently confirmed to represent essential thrombocytosis. In both cases, reconstructive operations for the cleft-related deformities were performed. CONCLUSIONS: Association of major hematological disorders and cleft lip, palate, or both is rare and is reported herein.

Adult↗

PubMed2000

The c-Jun N-terminal kinase pathway and apoptotic signaling (review).

The c-Jun N-terminal kinase (JNK) group of mitogen-activated protein kinases (MAPKs) is activated in mammalian cells by environmental stress, pro-inflammatory cytokines, and mitogenic stimuli. Biochemical and genetic studies demonstrate that JNK regulates the activities of many transcription factors, and that the JNK pathway is required for the regulation of inflammatory responses, cell proliferation, and apoptosis. The involvement of JNK in apoptotic cell death is particularly intriguing, and has been actively studied in recent years. An improved understanding of JNK-mediated apoptotic signaling may provide novel strategies in prevention and treatment of cancers.

Animals↗

PubMed2000

The Brief Psychiatric Rating Scale as an acute inpatient outcome measurement tool: a pilot study.

BACKGROUND: Recent guidelines for length of stay at psychiatric hospitals may have an unacceptable impact on patient outcome at discharge. A valid measurement tool is needed to evaluate significant patient change during brief hospitalization, typically 7 days, and to provide early prediction of unfavorable short-term outcome. This study examines the utility of the Brief Psychiatric Rating Scale (BPRS) as such a tool. METHOD: During a 2-month testing period, the BPRS was administered to 87 successive adults admitted to an acute general psychiatric inpatient unit at admission, 2 days, 7 days, and weekly thereafter until discharge. Total BPRS scores and 4 subscores were used in the data analysis, which included paired t tests and correlation analyses. RESULTS: Mean BPRS total scores demonstrate significant (p < .001) patient improvement at days 2, 7, and 14 of the hospital stay. Changes in subscores and their relationship to eventual outcome vary across diagnostic groups. CONCLUSION: The BPRS appears to be a useful inpatient outcome measure since it is capable of demonstrating significant change during brief stays of 1 week or less. Subscale scores may provide more specific prediction of change and may help clarify outcome in individual patients who show insignificant change by total score.

Adult↗

PubMed2000

Quantitative measurement on three-dimensional computed tomography: an experimental validation using phantom objects.

BACKGROUND: The use of 3-dimensional computed tomography (CT) imaging has been applied to the craniofacial region as well as to many other parts of the human body. Quantitative measurements have frequently been performed on the 3-dimensional images. However, critical validation of the measurement has been insufficient in the literature. This study was designed to evaluate the errors of the 3-dimensional measurements. METHODS: Four phantom objects, a cube, a sphere, a cylinder, and a life-size adult skull model, were scanned using standard CT acquisition protocol. The data were transferred, reformatted, and displayed on an IBM-compatible personal computer running AnalyzePC 2.5 software. Linear, area, and volume measurements were obtained using one of the two methods. The first was physical measurement of the phantom objects using a caliper for linear measurement and mathematical calculations for area and volume measurements. The second was done by computer measurement on 3-dimensional images using the AnalyzePC 2.5 program. Each measurement was performed twice. The differences were compared between the repeated measurements and between the two methods. RESULTS: The images were displayed according to standard 3-dimensional CT protocol. The differences between the measurements were insignificant and ranged from 0.00 to 2.57%. CONCLUSION: This study validated the accuracy of the quantitative measurements on 3-dimensional CT images.

Humans↗

PubMed2000

Isolation and characterization of phytochelatin synthase in rice seedlings.

Rice plants were treated with 50 microM copper sulfate to induce the synthesis of phytochelatins by means of a series of enzymatic reactions, including that of photochelatin synthase. Phytochelatin synthase extracted from 3-week-old rice seedlings was purified through a series of steps including precipitation with ice-chilled acetone, QAE A-50 anion exchange column, Amicon XM-50 ultrafiltration and Polybuffer Exchange (PBE) 94 chromato-focusing. This enzyme had a molecular mass of about 100 kDa with an isoelectric point of 4.0. The temperature and pH optima of this enzyme were 55 degrees C and pH 7.5, respectively. The enzyme was thermal tolerable and unstable under refrigeration at 4 or -20 degrees C. Cadmium was the most effective stimulator, followed by lead, copper, silver, cobalt and other divalent cations. Calcium and magnesium had no effect.

Acetone↗

PubMed2000

[Studies on metabolite of beta-elemene in rat bile].

AIM: To study the metabolite of beta-elemene in the bile of rat. METHODS: After i.v. 100 mg.kg-1 beta-elemene, the metabolite in rat bile was extracted by ether. Mass spectrometry, nuclear magnetic resonance, infrared spectrometry and ultraviolet spectrometry were used to analyze the metabolite of i.v. beta-elemene in rat bile. RESULTS: It was confirmed by nuclear magnetic resonance that the methyl of No. 11 carbon connecting with No. 10 carbon of a metabolite in rat bile was oxidized to be aldehyde. The molecular weight of the metabolite was 218 which detected by mass spectrometry. Infrared spectrometry and ultraviolet spectrometry proved that the aldehyde existed in the metabolite. The structure of the metabolite in bile of rat was identified, that was 1-methyl-1-ethenyl-2-isopropenyl-4-isopropenyl aldehydohexamethylene. CONCLUSION: The biotransformation of beta-elemene exists in vivo.

Animals↗

PubMed2000

Social support and life adjustment for teenagers with cleft lip and palate in Taiwan.

BACKGROUND: The teenage years (13-19 years) are a critical period for psychosocial development. Therefore, social support and life adjustment for teenagers with cleft lip/palate were chosen for investigation. METHODS: The sample survey included 101 cleft patients randomly selected from the Chang Gung Craniofacial Center, and 101 non-cleft controls selected from local middle and high schools for comparison. Questionnaires were used to evaluate the social support and life adjustment scales. Items of social support were subdivided into social activities, social service, and psychological support. Items of life adjustment were subdivided into social, psychological, and physical adjustments. RESULTS: The coefficients of alpha reliability were high at 0.9294 for social support, and 0.9389 for life adjustment. The results show that personal factors, family factors, and treatment status do not influence social support or life adjustment in either group; however, gender does. In the control group, non-cleft males had better social support and life adjustment than did females. Such a difference was not observed in the cleft group. Both groups received the same social support. The cleft teenagers have a significantly lower level of life adjustment. The association between the social support and life adjustment is high in both groups. CONCLUSION: The cleft group has a lower level of life adjustment. There is a positive relationship between social support and life adjustment. More social support is required for the cleft group in order to improve their level of life adjustment.

Adolescent↗

PubMed1999

Caspase-mediated cleavage and functional changes of hematopoietic progenitor kinase 1 (HPK1).

Activation of c-Jun N-terminal kinase (JNK) by Fas ligation is caspase-dependent, suggesting that caspases may regulate activators of the JNK pathway. Here, we report that an upstream activator of JNK, hematopoietic progenitor kinase 1 (HPK1), was cleaved during apoptosis. Cleavage of HPK1 was blocked by peptide inhibitors for caspases. HPK1 was efficiently processed by recombinant caspase 3 in vitro. A conserved caspase recognition site, DDVD (amino acids 382 - 385), was found in the HPK1 protein sequence. By testing HPK1 proteins with in vivo and in vitro cleavage assays, we showed that aspartic acid residue 385 is the target for caspases. HPK1 cleavage separated the amino N-terminal kinase domain from the carboxyl C-terminal regulatory domain, and enhanced HPK1 kinase activity. Unlike the full-length HPK1, the N-terminal cleaved product failed to bind adaptor molecules Grb2 (growth factor receptor-bound protein 2) and Crk (CT10 regulator of kinase). The C-terminal fragment, although having three proline-rich domains, bound to Grb2 and Crk less efficiently than the full-length HPK1 protein. Taken together, the cleavage of HPK1 by caspase profoundly changed its biochemical properties.

Apoptosis↗