Biomedical subjects

T J Chen

Publications and source records attributed to T J Chen.

At least 19 recordsLinked to original sources

PubMed2006

The prescriptions frequencies and patterns of Chinese herbal medicine for allergic rhinitis in Taiwan.

BACKGROUND: The evaluation of Chinese herbal medicines (CHM) to allergic rhinitis (AR) by large-scale pharmaco-epidemiological study is not ease found, although CHM had been reported to have potential effect for AR in some clinical trials. AIMS OF THE STUDY: To explore the frequency and pattern of CHM prescriptions on AR, we have the study by analysing the population-based CHM database in Taiwan. METHODS: The way for this study was linked and processed the complete traditional Chinese medicine database for Taiwanese recorded in the year 2002. The diagnosis of AR was extracted with the only single ICD-9 Code of 477 to calculate the frequency and pattern of prescriptions. Association rule was applied to analyse co-prescription of CHM for patients with AR. RESULTS: In the year 2002, among the 22 520 776 valid beneficiaries of the National Health Insurance, Taiwan, 914 612 subjects (3.8% of the total valid beneficiaries) have diagnosed AR. There were 35.6% of AR patients been treated by CHM. The peak age of AR patients treated by CHM was at the first decade (0-10). For the AR patients, the most common Chinese herbal formula prescription was Shin-yi-qing-fei-tang, or Angelica dahurica (Bai-zhi) for the single Chinese herb. While for the combination treatments the most common prescription was the two formulae, Xiao-qing-long-tang and Shin-yi-san. CONCLUSIONS: Because of the high utilization rate of the CHM treatment for AR, a large-scale randomized trial warrants further research for its efficacy and safety.

Adolescent↗

PubMed2004

Induction of VX2 carcinoma in rabbit liver: comparison of two inoculation methods.

Direct injection of VX2 cell suspension into the liver is simple and widely used. Implantation of a fragment of VX2 tumour into the liver using a surgical technique has also been developed in the last decade. In this study, we compared these two methods in order to find a better modality for establishing VX2 liver mass. Forty rabbits, each weighing 2.8-3.2 kg, were divided into two groups, 20 rabbits in each. In Group 1, a tumour cell suspension containing 1 x 10(6) cells in a volume of 0.1 ml, was injected slowly into the liver parenchyma using a 27-gauge needle during laparotomy. In Group 2, a 1 mm(3) fragment of VX2 carcinoma was inoculated into the sub-capsule of the left anterior lobe of the liver. In Group 1, three rabbits showed no tumour growth and 10 rabbits showed evidence of leakage and tumour seeding outside of the liver. In Group 2, all but one rabbit showed tumour growth and none showed evidence of tumour seeding. The leakage rates were 50% and 0% for Group 1 and Group 2, respectively. Overall, the success inoculation rate was 35% for Group 1 and 95% for Group 2. In conclusion, to create the VX2 liver tumour model in rabbits, direct implantation of VX2 tumour fragment into the liver achieved better results than injecting cell suspension of VX2 tumour into the liver.

Animals↗

PubMed2003

Analysis of marker or complex chromosomal rearrangements present in pre- and post-natal karyotypes utilizing a combination of G-banding, spectral karyotyping and fluorescence in situ hybridization.

The significance of complex chromosomal rearrangements presents a diagnostic dilemma. In the past, the use of G-banding coupled with fluorescence in situ hybridization (FISH) has been the standard approach. The recent development of spectral karyotyping (SKY) and multicolor FISH (M-FISH) has resulted in an increased accuracy of identification of marker or other complex chromosomal rearrangements. However, owing to the additional cost and time associated with SKY or M-FISH, and the restricted availability of such imaging facilities in many centers, it is not feasible to perform these procedures routinely on every sample. In addition, the identification of an aberration by SKY or M-FISH will often require confirmation by FISH. A practical approach is needed to take advantage of the complementary strengths of each method. In our center we utilize an algorithm that dictates the use of routine G-banding for the initial preliminary evaluation of a patient, followed by SKY characterization if marker chromosomes or complex translocations are detected by the G-banding analysis. According to this algorithm, FISH is used to verify the results once the origin of the abnormal chromosome has been determined by SKY. To demonstrate the effectiveness of this algorithm, we have analyzed both amniocyte and lymphocyte slides, using a combination of G-banding, SKY, and FISH. Our results confirm that an algorithm which selectively uses SKY or M-FISH will provide an efficient and improved method for pre- and post-natal chromosomal analysis.

Algorithms↗

PubMed2003

Trends in prescribing proton pump inhibitors in Taiwan: 1997 - 2000.

OBJECTIVE: The prescribing of proton pump inhibitors (PPIs) had increased greatly in recent years worldwide. Aim of our study was to analyze the utilization patterns of PPIs within the National Health Insurance program in Taiwan from 1997 - 2000. MATERIAL AND METHOD: The systemic sampling data-sets from the National Health Insurance Research Database served as data sources. Units of measurement for PPIs were numbers of prescription items and defined daily doses (DDDs). To estimate the proportion of the population treated daily with PPIs, numbers of DDDs per 1,000 inhabitants per day were calculated. In order to realize the role of PPIs in treating Helicobacter pylori-related disorders, we also analyzed various combined prescriptions of PPIs with amoxicillin, clarithromycin, metronidazole, tetracycline and bismuth. RESULTS: In the study period, PPI prescriptions increased nearly 2-fold at the outpatient sector and more than 3-fold at the inpatient sector. Men received more PPI prescriptions, as a whole, than women. Most PPIs were prescribed at the outpatient sector: 93.9% in 1997, 92.3% in 1998, 90.4% in 1999 and 87.3% in 2000. The numbers of DDDs per 1,000 inhabitants per day for all kinds of PPIs were 0.59, 0.78, 1.07, and 1.13 from 1997 - 2000, respectively. While the percentage of monotherapy increased from 63.6% in 1997 to 75.5% in 2000, the combination therapies did not experience a rapid and sustained growth. Among the combination therapies, PPI + amoxicillin + metronidazole and PPI + amoxicillin were popular in 1997 and 1998, but triple therapy with PPI + amoxicillin + clarithromycin predominated in 1999 and 2000. CONCLUSIONS: Despite increasing use, prescribing volumes of PPIs in Taiwan were far fewer than those in other developed countries. Treatment of Helicobacter pylori-related disorders in Taiwan followed universal standard.

Adult↗

PubMed2001

Novel SNP at the common primer site of exon IIIa of FGFR2 gene causes error in molecular diagnosis of craniosynostosis syndrome.

Most mutations in Crouzon, Pfeiffer, and Apert syndromes are in the extracellular, third immunoglobulin-like domain and adjacent linker regions (exons IIIa and IIIc) of the fibroblast growth factor receptor 2 (FGFR2) gene. Using the published primers for PCR, a patient with Crouzon syndrome was found to be homozygous for a mutation that results in a Q289P amino acid substitution in FGFR2. Two additional patients; one with Apert syndrome and P253R mutation, the other with Pfeiffer syndrome and S267P mutation, also appeared to be homozygous. Using a new primer located 146 bp 5' of exon IIIa for PCR followed by sequencing revealed an A to G polymorphism at -62 [corrected] position of exon IIIa. All three patients were heterozygous for both the mutation and the polymorphism. These results indicate that the polymorphism and the mutation are not on the same chromosome. The single nucleotide polymorphism is located at the second to the last base of the 3' end of the published primer. This primer mismatch caused the failure of amplification of the normal chromosome and thus, the apparent homozygosity. The frequency of this novel polymorphism was determined to be 0.03 by studying 326 chromosomes from the general population. We propose that a new primer should be used for mutational analysis of exon IIIa of FGFR2 to avoid misdiagnosis caused by primer mismatch.

Base Sequence↗

PubMed2001

Severe lactic acidosis caused by a novel frame-shift mutation in mitochondrial-encoded cytochrome c oxidase subunit II.

We report the first frame-shift truncation mutation in a mitochondrial DNA (mtDNA)-encoded subunit II of cytochrome c oxidase (COXII). The mutation was identified by temporal temperature gradient gel electrophoresis (TTGE) followed by direct DNA sequencing in an infant who died at 12 days of age following a course of apnea, bradycardia, and severe lactic acidosis. The patient had a twin brother who died at two days of age of similar course. The mutation, 8042delAT, produced a truncated protein that was 72 amino acids shorter than the wild type protein. The mutant protein, missing one third of the amino acid residues at the C-terminal essential for hydrophilic interaction with cytochrome c, ligand binding to CuA and Mg, and the formation of proton and water channels, apparently has devastating effects on mitochondrial respiratory function.

Acidosis, Lactic↗

PubMed2001

Involvement of apoptosis during deciduomal regression in pseudopregnant hamsters effect of progesterone.

We determined whether fragmentation of genomic DNA, apoptosis, occurs during deciduomal regression in pseudopregnant hamsters and the effect of progesterone on the apoptotic processes. Artificially induced deciduoma were obtained on different days of pseudopregnancy and separated into mesometrial and antimesometrial tissues. The deciduomal cell cycle progression and population profiles of both sides were compared by flow cytometry. The proportion of sub-G1 peak, which was correlated with the apoptotic cells, were about 10% on day 8 and reached to 40% in both tissues on day 10. Exogenous progesterone treatment by daily injection (2 mg; s.c.) on and after day 8 reduced the percentage of low molecular weight DNA in both tissues on day 10 and day 12 as compared to the nontreated control one, respectively. The appearance of DNA ladder was also delayed at least 24 h by progesterone administration. The intensity of DNA fragmentation was more pronounced in antimesometrial deciduoma. In situ 3'-end labeling of apoptotic cells further substantiated the apoptotic process. The apoptotic cells first appeared in the luminal region in antimesometrial deciduoma on day 8 and spreaded all over the entire deciduomal tissue on day 10. Progesterone treatment stimulated deciduomal proliferating cell nuclear antigen (PCNA) expression, maintained deciduoma until day 14 and retarded the differentiation and regeneration of the uterine epithelium.

Animals↗

PubMed2001

p53 and p21 expression in precancerous lesions and carcinomas of the uterine cervix: overexpression of p53 predicts poor disease outcome.

OBJECTIVES: Abnormal expression of the p53 and p21(waf1/cip1) tumor suppressor genes has been observed in a variety of human tumors, but little is known about its expression during cervical tumorigenesis. To identify the potential implications of both genes in the development of cervical carcinoma and explore the clinical importance of changes in gene expression, we assessed the levels of both proteins in precancerous lesions and carcinomas of the cervix. METHODS: In our study, 10 low-grade squamous intraepithelial lesions (LSIL), 35 high-grade squamous intraepithelial lesions (HSIL), 12 microinvasive carcinomas, and 103 invasive carcinomas were evaluated. The expression of p53 and p21 was studied by immunohistochemistry using monoclonal antibodies specific for these proteins. RESULTS: p21 was expressed in all samples of normal epithelium, LSIL, and HSIL, and the mean values of expression were 50.3, 42.5, and 44.5%, respectively. Conversely, the expression of p21 was significantly reduced in microinvasive (30.7%) and invasive carcinomas (9.9%). p53 nuclear staining was not detected in normal epithelium samples or LSILs, while 4 (11.4%) of 35 HSILs, 1 (8.3%) of 12 microinvasive carcinomas, and 38 (36.9%) of 103 invasive carcinomas were positive for p53. Compared with the results of the control group, precancerous lesions, and microinvasive carcinoma, the mean value of p53 expression (4.8%) in invasive carcinoma was significantly higher. Furthermore, p53 overexpression was significantly associated with advanced stage of the tumor (P < 0.001) [16/67 (23.9%) stage I, 15/28 (53.6%) stage II, and 7/8 (87.5%) stage III/IV]. In univariate analysis, p53 overexpression was a significant predictor of poor survival, whereas it had no independent influence on overall survival using the Cox regression method. Our data also revealed that no association between p53 immunostaining and p21 expression was found. CONCLUSIONS: The trend of reduced p21 expression in microinvasive and invasive carcinomas suggests that p21 may play a tumor-suppressor function in neoplastic transformation in cervical epithelium and inactivation of p21 may be an early event in cervical carcinogenesis. Our results indicated that p53 overexpression was a significant predictor of poor disease outcome in univariate analysis. Moreover, significantly increased expression of p53 in advanced-stage cervical carcinoma implies that inactivation of p53 is associated with tumor progression. Finally, this study further supports the notion that induction of p21 expression can be regulated in a p53-independent manner.

Adult↗

PubMed2001

Molecular genetics of glycogen-storage disease type 1a in Chinese patients of Taiwan.

The mutation spectrum of the glucose 6-phosphatase (G6Pase) gene in Chinese patients with type 1a glycogen-storage disease of Taiwan was studied by PCR/RFLP, temporal temperature gradient gel electrophoresis, and direct DNA sequencing methods. In addition to the two most prevalent mutations, 727G --> T (44.4%) and R83H (36.1%), that were detected by RFLP analysis, five other mutations, 341delG, 933insAA, Q104X, I341N, and H119L were identified. The frameshift mutations (341delG and 933insAA) and the nonsense mutation (Q104X) that produce truncated proteins are predicted to be disease-causing. The missense mutation, I341N, occurring in the last transmembrane domain of the ER-bound enzyme, retains a small amount of residual activity of approximately 10%. Except for R83H, the mutations have been described only in Asians. H119L, however, is of particular interest because of the essential role of the catalytic histidine of phosphohydrolase. This amino acid is believed to be involved in the formation of the phosphoryl-enzyme intermediate during catalysis. The patient who was compound heterozygous for 727G --> T and H119L mutations had essentially no G6Pase activity in her liver biopsy. This observation is consistent with the importance of H119L in catalysis.

Base Sequence↗

PubMed2001

Concomitant prescription of non-steroidal anti-inflammatory drugs and antacids in the outpatient setting of a medical center in taiwan: a prescription database study.

OBJECTIVE: Although antacids were ineffective in preventing serious gastrointestinal complications caused by non-steroidal anti-inflammatory drugs (NSAIDs), many physicians in Taiwan still prescribe antacids concomitantly with NSAIDs. A survey of an outpatient prescription database was performed to measure the extent of such a combination and to explore its associated factors. METHODS: One month of the outpatient prescription data in the polyclinic of a medical center in Taiwan served to estimate the frequency of concomitant antacid prescription with NSAIDs. The age of patients, duration of NSAID prescriptions, concomitant prescription of corticosteroid or ulcer-healing drugs, and inter-departmental variations were compared between the NSAID prescriptions with and without antacids. RESULTS: Antacids were present in 87.3% of prescriptions with NSAIDs but only in 34.4% of prescriptions without NSAIDs (P<0.001). The prescription of antacids was significantly associated with the prescription of NSAIDs. The age of patients and duration of NSAID prescriptions did not influence the co-prescription of NSAIDs and antacids. Significant inter-departmental variations were noted in which the surgeons and orthopedic doctors tended to co-prescribe antacids with NSAIDs more often than the internists. CONCLUSION: The physicians in Taiwan tended to prescribe NSAIDs together with antacids. The rationality of this co-prescription deserves further investigation.

Academic Medical Centers↗

PubMed2001

An initial assessment of the feasibility and effectiveness of implementing diabetes shared care system in Taiwan--some experiences from I-Lan County.

Diabetes is the fifth leading cause of death in Taiwan and the burden of suffering is still increasing. Building a comprehensive and efficient health care system is crucial to improve the outcome of the diabetics. We implemented the first diabetes shared care system of Taiwan in I-Lan County since August 1996 under the support of Department of Health, the Executive Yuan. This county-wide system was named 'Lan-Yang Diabetes Shared Care System' by the regional steering committee. Regional guidelines for diabetes management were developed after extensive discussion. A multidisciplinary diabetes care team was organized through a training and certification process. Registered patients held diabetes passports to keep clinical record. Physicians of the system use shared referral protocols and sheets. By the end of June 1999, 99 medical professionals had completed their training for diabetes shared care and been certified. The shared care system awarded 26 clinics to hang the lamp signs with the system logo to make them distinguishable. Such clinics have now been available throughout 12 townships in I-Lan County. The number of registered patients carrying diabetes passport increased to 3484 and there was a community-based patient group in every township of I-Lan County. The amount of continuing diabetes clinical training delivered by the specialists to the primary care physicians and non-physician professionals increased to 1681 person-hours per year. The proportion of registered patients undertaking fundus examination within 1 year increased to 30.9%, checking urine micro-albumin to 28.0% and checking HbA(1c) 72.8%, respectively. Mean HbA(1c) value decreased from 8.7% in the first year to 7.9% in the third year. Our study showed that under the co-ordination by regional health bureau with integration of different levels of medical facilities, governmental sectors and non-governmental community resources, the diabetes shared care model is feasible in Taiwan. Through its implementation, quality of regional diabetes care has achieved preliminary improvement.

Delivery of Health Care↗

PubMed2001

Antibiotic usage in primary care units in Taiwan after the institution of national health insurance.

To understand antibiotic usage in primary care units in Taiwan after the institution of national health insurance, we collected all prescriptions for one week in March each year from 1996 to 1999 from out-patient clinics of randomly sampled public health stations located in various parts of Taiwan. We sampled 114 health stations with 40,891 patient-visits and 68,386 diagnoses made in 1996; 154 health stations were sampled with 53,992 patient-visits and 99,466 diagnoses in 1997; 166 health stations were sampled with 49,112 patient-visits and 96,161 diagnoses in 1998; and 162 health stations were sampled with 46,976 patient-visits and 93,641 diagnoses in 1999. The percentages of total patient-visits that resulted in antibiotic treatment were 14.2%, 12.5%, 14.1% and 13.0% in the four time periods, respectively. Among patient-visits, patient group under the age of 11 received the highest percentage of antibiotic treatment. Common cold was the most frequent diagnosis for which antibiotic was prescribed during the four time periods, accounting for 32.3% of total antibiotic prescriptions. Among patients with the diagnosis of common cold, 31.3% received antibiotic treatment, and the highest figure was among pediatric patients (<16 year of age). Penicillins, cephalosporins and macrolides were the most commonly prescribed classes of antibiotics. They accounted for 35.4%, 26.5% and 21.6% of all prescribed antibiotics in these four study periods. From this study, it was found that, after institution of the national health insurance system, antibiotics are still very commonly used in primary care units in Taiwan and still seem to be overused.

Adolescent↗

PubMed2001

Left atrial and ventricular ball thrombi complicating rheumatic heart disease with combined mitral and aortic stenosis.

A 42-year-old woman with chronic mitral stenosis was admitted for progressive dyspnea, palpitation, and weakness of lower extremities. Echocardiography revealed rheumatic, thickened, and stenotic mitral and aortic valves, and two free-floating ball thrombi were detected in the left atrium and ventricle, respectively. She died suddenly the next day, probably due to mitral or aortic outflow obstruction by the ball thrombi. We believe that the occurrence of free-floating ball thrombi in both the left atrium and left ventricle concomitantly has never been reported.

Aged↗

PubMed2001

Association analysis for dopamine D2 receptor Taq1 polymorphism with P300 event-related potential for normal young females.

P300 has been demonstrated abnormal for a variety of neuropsychiatric disorders, and heritability has been proposed. We analyzed the event-related potentials for three DRD2 genotype groups in 134 normal young females. The results demonstrate that there is no association for DRD2 genotype and P300 components. Our negative findings in normal subjects suggest association demonstrated for P300 latency and the DRD2 allele may be disease dependent.

Adult↗

PubMed2001

Administration of chinese herbal medicines facilitates the locomotor activity in dystrophin-deficient mice.

The purpose of this study was to access the effects of chinese herbal medicines on Duchenne muscular dystrophy (DMD). We use dystrophin-deficient mice (mdx), an animal model of DMD, to evaluate the effect of chinese herbal medicines on locomotor activity. The consumption of water for each mouse was controlled during the three-month experimental session. Each mouse was allowed to drink 3 ml water with or without herbal medicines daily for three months. The estimated intake of chinese herbal medicine in adult mdx mouse with 30 g weight is 100 mg/kg per day, close to a dose used in human. The locomotor activity of the mdx mice was measured every month. Monitoring the locomotor activity of mdx mice after three-month administration of chinese herbal medicines, the results showed that liu-wei-di-huang-wan (LDW) and san-lin-pai-tsu-san (SPS) can facilitate locomotor activity with the parameters of horizontal activity, total distance, number of movements, movement time, vertical activity, number of vertical movements, vertical movement time, stereotypy, number of stereotyped movements, and stereotyped movement time. These results suggest that either LDW or SPS can act as a potent herbal medicine for the pharmacological treatment of DMD patients.

Analysis of Variance↗

PubMed2001

Acute myocardial infarction after upper gastrointestinal gastroscopy.

We describe a patient with gastric ulcer confirmed by upper gastrointestinal endoscopy who developed an acute Q wave myocardial infarction involving both the anterior and inferior wall shortly after the procedure. This life-threatening complication of gastroendoscopy was clearly demonstrated through studies of electrocardiogram, cardiac enzymes, echocardiogram and cardiac catherterization. We suggest that preventive measures should be implemented so that endoscopy can be performed under optimal conditions, especially for elderly patients with history of heart disease.

Aged↗

PubMed2000

Evaluating the protective role of the olivocochlear bundle against acoustic overexposure in rats by using Fos immunohistochemistry.

Efferent inhibition on the cochlea is suggested as a possible function of the olivocochlear bundle (OCB). Substantial evidence supports the finding that the OCB may protect the inner ear from noise-induced damage. However, there is relatively less known about the effects of noise on the central auditory transmission compared to the effects on the periphery. In the present animal study, two experimental paradigms were designed to analyze the influence of OCB lesion on the central auditory transmission following acoustic overexposure. In order to evaluate the animal's auditory function, its hearing threshold and the tone-evoked Fos expression shown in auditory nuclei were examined. Fos is a protein product of proto-oncogene c-fos. Via appropriate acoustic stimulation, Fos expression reveals the activated neuronal elements along the ascending auditory pathway. Thus, in experiment 1, no exposure sound was introduced and therefore no significant differences were shown in hearing thresholds and Fos expression among all rats, regardless of the status of their OCB. This result indicates that, without acoustic overexposure, OCB lesion caused no significant effect on brainstem auditory transmission. In contrast, in experiment 2, rats were exposed to continuous 8 kHz tones at 85 dB sound pressure level (SPL). A significantly increasing threshold was observed in rats with OCB lesion following an exposure period of 5 or 10 days. In addition, Fos expression was invisible first in rats with OCB lesion following 5-day exposure and almost no Fos expression could be examined in all rats after 10-day exposure. Taken together, the present data demonstrate that damaging the OCB renders an animal more easily vulnerable to acoustic damage than that of rat with intact OCB, and then reduces its cochlear activities, which eventually leads to increasing difficulty to induce tone-evoked Fos expression along the ascending auditory pathway.

Animals↗

PubMed2000

Impaired vascular dynamics in normotensive diabetic rats induced by streptozotocin: tapered T-tube model analysis.

This study is to explore the changes of arterial mechanical properties in streptozotocin (STZ)-diabetic rats, based on the exponentially tapered T-tube model. Rats given STZ 65 mg kg(-1)i.v. are compared with untreated weight- and age-matched controls. A high-fidelity pressure sensor and electromagnetic flow probe measured pulsatile pressure and flow waves in the ascending aorta, respectively. Diabetic rats exhibit isobaric vasodilatation that is characterized by an increase in cardiac output and no significant changes in aortic pressure. Total peripheral resistance of diabetic rats is lower than that of weight- and age-matched controls. Diabetic rats have higher total peripheral compliance (2.86+/-0.70 microl mm Hg(-1)) than do weight- (1.77+/-0.34 microl mm Hg(-1)) and age-matched (1.87+/-0.69 microl mm Hg(-1)) controls. Aortic characteristic impedance is reduced from 0.017+/-0.003 mm Hg min kg ml(-1)in weight- and 0.020+/-0.004 mm Hg min kg ml(-1)in age-matched controls to 0.010+/-0.004 mm Hg min kg ml(-1)in diabetic rats. Moreover, diabetic rats show shorter wave transit time in lower body circulation (17.86+/-1.91 ms) than do weight- (20.45+/-1.91) and age-matched (23.05+/-2.04 ms) controls. Under isobaric vasodilatation, the decreased resistance and increased compliance in peripheral circulation suggest that the contractile dysfunction of the smooth muscle cells may occur in resistance arterioles in diabetes. With unaltered aortic pressure, an impairment in aortic distensibility of STZ-diabetic rats is manifest on the reduced wave transit time rather than on the diminished aortic characteristic impedance.

Animals↗