Biomedical subjects

M C Chou

Publications and source records attributed to M C Chou.

At least 19 recordsLinked to original sources

PubMed2006

Thallium-201 scan in evaluating thyroid nodules following equivocal fine-needle aspiration cytology.

UNLABELLED: The AIM of this prospective study was to evaluate the usefulness of the thallium-201 ( (201) Tl) thyroid scan in the detection of malignancy in cold thyroid nodules whose status was equivocal following palpation fine-needle aspiration cytology (FNAC). PATIENTS, METHODS: Fifty-one patients with clinically palpable solitary cold thyroid nodules classified as non-diagnostic or suspicious following biopsy underwent (201) Tl thyroid scans. Each scan was performed 15 min (early scan) and 3 h (delayed scan) after an intravenous administration of 74 MBq (201) Tl. Thallium uptake in the nodules was visually assessed and scored on a three point scale, with a grade of three defining malignancy. All patients underwent surgery and the histopathology of nodule tissues were compared with results of the scans. RESULTS: Fifty-one nodules were examined. Forty were benign and 11 were malignant. For early scans, the diagnostically relevant parameters were: sensitivity (100%), specificity (75%), and accuracy (80%). Corresponding findings for the delayed scan were: 91%, 98%, and 96%. CONCLUSION: The (201) Tl scan is useful for detecting malignancy in cold thyroid nodules classified as nondiagnostic or suspicious lesions by FNAC.

Biopsy, Fine-Needle↗

PubMed2005

Oral administration of paclitaxel affects the distribution and metabolism of 2-aminofluorene in various tissues of Sprague-Dawley rats.

To evaluate the question of whether or not paclitaxel affects the distribution and metabolism of chemical carcinogens such as 2-aminofluorene (AF) on Sprague-Dawley rats were examined. The AF, acetylated AF and AF metabolites were determined and examined by using high performance liquid chromatography. After having received AF only, AF with paclitaxel at the same time and paclitaxel pretreated for 24 h then treated with AF for 24 h, urine, stool and tissues such as liver, kidneys, stomach, colon, bladder and blood were collected and assayed for AF and its metabolites. Compared to the control group, paclitaxel caused an increase of the metabolites excreted in urine and stool. The major metabolite excreted in urine and stool was 9-OH-AAF. The liver is the major metabolism center and the major residual metabolite of AF in the liver was also 9-OH-AAF.

Acetylation↗

PubMed2002

Needlescopic thoracic sympathetic block by clipping for craniofacial hyperhidrosis: an analysis of 28 cases.

BACKGROUND: Endoscopic thoracic sympathectomy or sympathicotomy of the lower part of the stellate ganglion is an efficient method for the treatment of craniofacial hyperhidrosis, but postoperative compensatory sweating may be troublesome in some patients. Needlescopic thoracic sympathetic block by clipping may achieve a similar effect as well as providing a possible reverse operation for patients who suffer from intolerable postoperative compensatory sweating. METHODS: Between January 1998 and June 2000, we collected a total of 28 patients with craniofacial hyperhidrosis. There were 15 men and 13 women with a mean age of 39.2 years (ranges, 19-50). All patients were placed under single-lumen intubated anesthesia in a semisitting position. Two ports were needed. We used a 2-mm 0 degrees thoracoscope and endo clips to perform a sympathetic block by clipping the lower third of the stellate ganglion at the second intercostal space. RESULTS: The operation was usually accomplished within 20 min (ranges, 15-30). All patients were discharged within 4 h after the operation. There were no surgical complications or surgical mortality cases. All patients achieved improvement of craniofacial hyperhidrosis without recurrent symptoms after a mean of 25.3 months (range, 12-41) of follow-up. Twenty-five patients (85.7%) developed compensatory sweating of the trunk and lower limbs. One of these patients could not tolerate this postoperative sweating; he therefore underwent a reverse operation and obtained improvement of the compensatory sweating 18 days after removal of the endo clips. CONCLUSION: Needlescopic thoracic sympathetic block by clipping is a safe and effective method for the treatment of craniofacial hyperhidrosis; compensatory sweating may be improved after a reverse operation and removal of the endo clips.

Adult↗

PubMed2002

The effect of paclitaxel on gene expression and activity of arylamine N-acetyltransferase and DNA-2-aminofluorene adduct formation in human leukemia HL-60 cells.

N-Acetylation is recognized as the first step in arylamine metabolism. The enzyme responsible for N-acetylation is called arylamine N-acetyltransferase (NAT),which uses acetyl coenzyme A as the acetyl group donor. Paclitaxel has been shown to exhibit antineoplastic and anticancer activity. In this study, paclitaxel was selected to determine the inhibition of arylamine N-acetyltransferase activity, gene expression (NAT mRNA) and DNA-2-aminofluorene adduct formation in human leukemia HL-60 cell line. Paclitaxel (0.01-l microM) did decrease the level of NAT mRNA in a dose-dependent manner. The results demonstrated that paclitaxel inhibited NAT activity and DNA-2-aminofluorene adduct formation in human leukemia HL-60 cells in a dose-dependent manner. Using standard steady-state kinetic analysis, it was demonstrated that paclitaxel was a possible uncompetitive inhibitor to NAT activity in cytosols based on the decrease in apparent values of K(m) and V(max). This report is the first demonstration that paclitaxel affected human leukemia HL-60 cells NAT activity and DNA-2-aminofluorene adduct formation.

Acetylation↗

PubMed2001

Standing localized cluster in a continuum traffic model.

We study the emergence of standing localized cluster in a continuum traffic model. The local-density profile, local velocity profile, and the phase boundary are obtained. The effect of the on ramp is discussed. The indication of the boundary induced phase transition is also discussed.

Journal Article↗

PubMed2001

Factors associated with errors in death certificate completion. A national study in Taiwan.

To identify characteristics of certifying physicians and the deceased that are associated with errors in death certificate completion in Taiwan, we retrospectively reviewed 4123 systematically sampled death certificates issued in 1994. Multivariate analyses were used to assess the associations of various characteristics of the certifying physicians and the deceased with four types of error. Of the 4123 death certificates reviewed, 2525 (61%) were completed correctly. In 289 (7%), only the mechanism(s) of death was given (Major Error 1); in 146 (4%), multiple causal sequences were given in part I (Major Error 2); in 800 (19%), a single causal sequence was given but was not specific enough (Minor Error 1); and in 363 (9%), a single causal sequence was given but the order was incorrect (Minor Error 2). Multiple logistic regression analyses revealed that the probability of error in death certification increased as the age of the deceased increased, the age of the certifier decreased, and the level of the hospital decreased. These findings suggest that training in death certificate completion should focus on younger certifiers and those working at lower level teaching hospitals and nonteaching hospitals. Given the high rate of Minor Error 1, physicians should be reminded to state information as specifically as possible to render cause-of-death statistics more informative.

Adult↗

PubMed2001

Diversity in death certification: a case vignette approach.

Previous studies have revealed high rates of errors in death certification, but few have discussed the nature of these errors. To explore the diversity among physicians in death certification and its relationship with the complexity of the causal sequence of death, we asked 145 physicians attending a continuing medical education course to complete the cause-of-death section on dummy death certificates of four case vignettes. The difficulty in determining the causal sequence of death varied from relatively simple to complex. Variations in death certification were classified according to wording, diagnostic semantics, combinations of expressions, correctness of certification format, and concordance with the referent underlying cause of death (UCOD). Given the same case history information, physicians showed great variation in wording and diagnostic semantics in death certification. The rates of correct certification format and concordance with referent UCOD varied with the level of complexity of the causal sequence of death. The greatest source of diversity was choosing between an acute condition of a chronic disease and the chronic disease itself, and between competing prominent comorbidities. Experience in death certification was significantly associated with correct certification format but not with concordance with referent UCOD. Knowledge of death certification was not associated with correct certification format or concordance with referent UCOD. Our findings indicate that the traditional concept of UCOD tabulation and using a single standard ICD code in evaluating the quality of death certification oversimplifies a complex situation. Variations in death certification, especially the selection of UCOD, were due to differences in interpreting the information rather than differences in knowledge of death certification.

Acute Disease↗

PubMed2001

Association of risk-taking behaviors with adolescent childbearing.

BACKGROUND AND PURPOSE: Risk-taking behavior has been shown to be associated with adolescent pregnancy or childbearing. However, the specific risk-taking behavioral factors and the extent to which they are associated with adolescent childbearing is less clear. The purpose of this study was to determine the risk-taking behavioral factors associated with adolescent childbearing. METHODS: In this case-control study, 198 mothers aged from 16 to 19 years with first-born infants born in Taichung City in 1997 were enrolled. The controls were adolescents with no history of childbearing or pregnancy matched for age and residential neighborhood of each case. A self-administered structured questionnaire inquiring about a variety of risk-taking factors was used to gather relevant information. The logistic regression model was used for univariate, combination of variables, and multivariate analysis. RESULTS: Compared to controls, childbearing adolescents were more likely to have risk-taking behaviors including smoking, drinking, use of illegal substances, working at bars or nightclubs, and lack of use of contraception at first sexual intercourse. Logistic regression analysis for various combinations of risk-taking behaviors revealed that the more items of risk-taking behaviors adolescents had, the higher their risk of childbearing. Multiple logistic regression analysis showed that use of alcohol (adjusted OR = 1.9, 95% CI 1.1-3.1), working at sex-related workplace (adjusted OR = 4.7, 95% CI 2.4-9.3), and no use of contraceptive device at first intercourse (adjusted OR = 3.1, 95% CI 1.3-7.2), were significant risk factors for adolescent childbearing in subjects with previous sexual intercourse. CONCLUSION: Adolescent females who used alcohol, worked at bars or nightclubs or used no contraception at first intercourse were more prone to adolescent childbearing, and a combination of risk-taking behaviors could increase the risk of childbearing. These risk-taking factors should be taken into consideration in the development of prevention programs.

Adolescent↗

PubMed2001

Tamoxifen inhibits arylamine N-acetyltransferase activity and DNA-2-aminofluorene adduct in human leukemia HL-60 cells.

Genetic regulation of acetyl coenzyme A-dependent N-acetyltransferase (NAT)and O-acetyltransferase (OAT) activities may play an important role in the metabolic activation of arylamine chemicals and carcinogens. N-acetylation is thought to be the first step in arylamine metabolism. The enzyme responsible for N-acetylation is called NAT. In this study, synthetic non-steroidal antiestrogen tamoxifen was selected for determining the inhibition of arylamine NAT activity, gene expression (NAT mRNA) and DNA-2-aminofluorene adduct formation in human leukemia HL-60 cell line. The results demonstrated that tamoxifen did not affect the level of NAT mRNA in HL-60 cells. But the results also showed that NAT activity and 2-Aminofluorene-DNA adduct formation in HL-60 cells were inhibited and decreased by tamoxifen in a dose-dependent manner when the doses of tamoxifen up to 100 micro M. We also examined the standard steady-state kinetic analysis, and the data showed that tamoxifen may be an uncompetitive inhibitor to NAT activity in cytosols based on the decrease apparent values of Km and Vmax. This report is the first finding that tamoxifen inhibited human leukemia HL-60 cells NAT activity and DNA-2-aminofluorene on adduct formation.

2-Acetylaminofluorene↗

PubMed2000

Regional mortality from motor vehicle traffic injury: relationships among place-of-occurrence, place-of-death, and place-of-residence.

Regional mortality data, which are compiled according to place-of-residence of the decedent, are an important reference for regional health planning and resource allocation. However, it would be inappropriate to apply these data to studies of environmental risk factors if a large proportion of fatal motor vehicle traffic injuries (MVTI) in fact occur outside the resident county. The aim of this study was to determine the proportion and characteristics of residents of a rural area of Taiwan who died from MVTIs that occurred outside the county of residence. We also explored the relationships among the place-of-occurrence, place-of-death, and place-of-residence of these decedents. The families or neighbors of residents of Huatung Area (eastern Taiwan) who died from MVTIs in 1994 or 1995 were interviewed to identify the place-of-occurrence of the MVTI. Of the 882 Huatung Area residents who died as a result of an MVTI during the study period and for whom relevant data were available, the MVTI occurred outside the resident county in 207 (23%) cases. Residents whose MVTI occurred outside the county of residence were more likely to be youths (aged 15-24) or young adults (aged 25-44) and driving automobiles or trucks. Of the 866 cases in which the exact place was known, the place-of-occurrence and the place-of-death (recorded on the death certificate) were in the same county in 849 (98%). Because a high proportion of fatal MVTIs occurred outside the resident county, the mortality rate calculated according to place-of-residence does not accurately reflect the environmental risk factors in this area. The finding that the characteristics of those whose MVTI occurred outside the county differed from those decedents whose MVTI occurred within the county indicates that there are two target groups for prevention programs. In addition, at least in Huatung Area, the place-of-death recorded on the death certificate could serve as a surrogate for the place-of-occurrence in epidemiologic studies.

Accidents, Traffic↗

PubMed2000

Accuracy of cause-of-death coding in Taiwan: types of miscoding and effects on mortality statistics.

BACKGROUND: The objectives of this study were to assess the accuracy of cause-of-death coding, determine the extent to which coders follow the selection rules of coding set out in the International Classification of Diseases, 9th Revision (ICD-9), and the effects of miscoding on mortality statistics in Taiwan. METHOD: A systematic sample of 5621 death certificates was reviewed. The underlying cause of death (UCD) selected by the reviewer for each death certificate was compared with that selected by the original coder. The UCD was selected according to ACME (Automated Classification of Medical Entities) Decision Tables. RESULTS: The overall agreement rates between the reviewer and coders according to the three-digit and two-digit categories of ICD-9 were 80.9% and 83.9%, respectively. Good agreement was found for malignant neoplasms (kappa = 0.94) and injuries and poisoning (kappa = 0.97), but there was poor agreement for nephrotic diseases (kappa = 0.74), hypertension-related diseases (kappa = 0.74), and cerebral infarction (kappa = 0.77). Reasons for disagreements included disagreement in nomenclature (42.8%), inappropriate judgement of causal relationships (41.5%), and incorrect interpretation of Selection Rule 3 and Modification Rules (15.7%). CONCLUSION: This study showed various levels of agreement for different diseases between the reviewer and the original coders in selection of the UCD. Owing to the 'compensatory effect of errors', the national mortality statistics were not affected significantly. The national administration should undertake routine internal studies to control the quality of UCD coding practices.

Age Distribution↗

PubMed1999

Demographic characteristics of fathers of infants born to adolescent mothers in Taiwan.

It has been well accepted that effective programs for prevention of adolescent pregnancy should involve adolescent women and their partners. Using data from certificates of live births in Taichung County, Taiwan, in 1994, the demographic characteristics of fathers whose infants were born to adolescent women were compared with a matched group fathers whose infants were born to women aged > or =20 years. Most of the fathers of infants born to adolescent women were adults: 57% of the fathers of infants born to women aged < or =15 years were > or =30 years of age. Fathers of infants born to adolescent women had a lower educational level than that of matched fathers. These demographic characteristics of fathers should be carefully interpreted and taken into consideration in developing intervention programs.

Adolescent↗

PubMed1999

Relationship between pterygium/pinguecula and sunlight exposure among postmen in central Taiwan.

BACKGROUND: The purpose of this study was to investigate outdoor hazards and their relationship to conjunctival disorders experienced by postmen. METHODS: Three hundred and ninety-four employees (248 postmen and 146 officers) working in 11 post offices in central Taiwan were recruited and participated in the 1994 annual labor health examination. Pinguecula and pterygium were diagnosed by an ophthalmologist. Meanwhile, detailed personal and occupational information was obtained using a structured questionnaire. The cumulative occupational sunlight exposure was calculated for each postman by considering the duration of their employment as postmen, the average working hours per day and their spectacle use (sunglasses and eyeglasses). A logistic regression was used to analyze the relationship between cumulative occupational sunlight exposure and pinguecula. RESULTS: Among the postmen, the prevalences of pinguecula and pterygium were 62.9% and 7.3%, respectively. The outdoor nature of postal work was significantly associated with the occurrence of pinguecula as well as pterygium (p < 0.05). When the cumulative occupational sunlight exposure increased by one unit (one year x hour/day), the risks of developing pinguecula and pterygium were raised by 2.1% and 0.8%, respectively. CONCLUSIONS: The results indicate that conjunctival disorders were associated with the cumulative occupational sunlight exposure of postmen working outdoors. This study reinforces the importance of ocular protection from sunlight.

Adolescent↗

PubMed1998

Association of parental characteristics with adverse outcomes of adolescent pregnancy.

BACKGROUND: It is well-known that pregnancy in adolescence has an increased risk of adverse reproductive outcomes. It remains unclear whether this association is due mainly to the unfavourable sociodemographic status or due solely to biological immaturity of pregnant adolescents. OBJECTIVE: The purpose of this study was to determine the association of parental sociodemographic characteristics with the adverse outcomes of adolescent pregnancy. METHOD: Data from certificates of live births in Taichung County, Taiwan in 1994 of 7994 singleton, first-born babies whose mothers were 15-34 years of age were analysed. The relative risk of having adverse pregnancy outcomes for adolescent subgroups was obtained as compared with that among mothers 20-34 years of age with the same characteristics. The adjusted relative risk of having adverse pregnancy outcomes for each covariate was calculated by a multiple logistic regression analysis. RESULTS: Of 7994 babies born to mothers of 15-34 years of age, 8.3% were born to adolescent mothers. In all age groups, the younger adolescent mothers (15-17 years of age) had the highest percentage of both infants with low birth weight (10.6%) and preterm births (7.1 %). Younger adolescent mothers in almost all sociodemographic categories had higher risks of having both low-birth-weight and preterm births than those of older adolescent mothers. Multiple logistic regression analysis showed that a younger maternal age is the only significant risk factor for having infants with low birth weight (adjusted RR = 2.5, 95% Cl 1.8-4.5 and adjusted RR = 1.7, 95% Cl 1.2-2.6 for younger and older adolescent mothers, respectively) or preterm birth (adjusted RR = 1.9, 95% Cl 1.1-3.4 and adjusted RR = 1.5, 95% Cl 1.0-2.3 for younger and older adolescent mothers, respectively). CONCLUSIONS: Adolescent pregnancy carries an increased risk of having low-birth-weight and preterm births, and a younger maternal age is causally implicated.

Adolescent↗

PubMed1998

Trends in injury mortality among adolescents in Taiwan, 1965-94.

OBJECTIVES: To describe trends in injury mortality among adolescents in Taiwan for prioritising preventive interventions. METHODS: Adolescent injury mortality data for Taiwan were derived from official publications of vital statistics from 1965 to 1994 to determine trends by sex and cause of death. Simple linear regression was used to test the trends. RESULTS: The number of deaths due to injury among adolescents aged 10-19 years in Taiwan increased from 983 in 1965 to 1783 in 1994, an 81% increase. The injury mortality rate increased 42%, from 32.2 per 100,000 in 1965 to 45.6 per 100,000 in 1994. The proportion of injury deaths also increased, from 45.3% in 1965 to 72.8% in 1994. The trends in mortality from motor vehicle injury (MVI) among four demographic groups were all significantly positive (p < 0.001). The proportion of deaths due to MVI among injury was 14% in 1965 and increased to 63% in 1994. CONCLUSIONS: The increase in injury mortality rates among adolescents over the past three decades appears to be due largely to the increase in MVI mortality rates with males aged 15-19 years accounting for most of this increase. Priorities for adolescents in Taiwan are MVI (especially motorcyclists) and drownings.

Accidents↗

PubMed1998

Seasonal variation of chickenpox, mumps and rubella in Taiwanese children estimated by pediatric clinics.

To determine the seasonal variation of childhood infectious diseases in Taiwan, the incidence rates of chickenpox, mumps and rubella were studied by analyzing patient's records collected from pediatric clinics in northern, central, southern and eastern Taiwan from January 1, 1993 to December 31, 1993. The study revealed that a chickenpox outbreak was most likely to occur in autumn, followed by a second peak in spring, and the lowest rate in summer. In this study, the highest monthly incidence of chickenpox was 540 cases per 100,000 population. The highest incidence of mumps occurred in the spring, the second highest in autumn, and the lowest during summer. Cases of rubella occurred in the spring, summer and autumn, but not in the winter. The data on chickenpox from this study revealed a similar seasonal pattern every year to that of the Department of Health of the National Quarantine Service on Taiwan. The chickenpox virus is known to be relatively sensitive to elevations in ambient temperature and is characterized by its occurrence mainly in slightly humid seasons.

Chickenpox↗

PubMed1998

Factors related to adolescents' perceptions of treatment outcomes in an adolescent health clinic.

To determine factors related to adolescents' perceived treatment outcomes of their health problems in an adolescent health clinic located at a college hospital, 246 adolescent patients between the ages of 11 and 21 who visited the clinic twice or more during the period January 1994 to December 1995 were included in this study. Information concerning adolescents' sociodemographic characteristics, family function, office visits and health problems of first visits was collected by reviewing subjects' medical and other clinic-related records. In addition, a structured questionnaire was mailed to assess subjects' satisfaction with physicians and the environment and services provided by the clinic as well as their perceived treatment outcomes. 148 patients completed the questionnaire, a response rate of 60.2%. Most of the respondents were in late-stage adolescence (71.0%) and were in school (71.0%). About half of respondents had normal family function, while the other half had moderate or severe family dysfunction. Most of the health problems of respondents were acute (64.2%) and were biological (76.4%) conditions. Most of the respondents were satisfied with the various characteristics of physicians except confidentiality emphasized by the physicians, while many fewer respondents were satisfied with the environment and services provided by the clinic. Family function, physicians' respect toward the adolescents, and the adolescents' satisfaction with the services provided in general were the factors significantly related to adolescents' perceived treatment outcomes based on a stepwise, multiple logistic regression analysis. We conclude that efforts to provided could result in better adolescent perceived treatment outcomes.

Adolescent↗

PubMed1997

Molecular nature of a sperm acrosomal antigen recognized by HS-13 monoclonal antibody.

Among the numerous monoclonal antibodies generated against human sperm antigens, HS-13 monoclonal antibody was shown to react with an intra-acrosomal antigen from human, mouse and rat. In this study, HS-13 was used as the affinity ligand for the purification of the cognate antigen from human sperm by immunoaffinity chromatography. The purified cognate antigen from human sperm, designated as HSAg-13, was found to be a protein with a molecular weight of approximately 80 kDa on SDS-PAGE in the presence of reducing reagents. This monoclonal antibody was used as the probe to study the tissue distributions and developmental expression of the cognate antigen from human, mouse and rat by immunohistochemical assays. It was concluded that the antigen recognized by HS-13 antibody is highly sperm specific and found only in sperm and mature testis, but not in any other somatic tissues examined in human and mouse. The antigen was shown to be expressed at the postmeiotic stages of spermatogenesis in mouse and rat. By using indirect immunofluorescent staining assay, HS-13 was shown to react only with the methanol-fixed acrosome-intact sperm but not with the live sperm. Following calcium ionophore A23187 treatment, acrosome-reacted sperm showed either negative staining or residual staining in the equatorial region, suggesting the intra-acrosomal location of HSAg-13. The spontaneous acrosome reaction following overnight incubation in BWW medium resulted in a statistically significant decrease of antibody-stained human sperm. In view of excellent correlations for the scoring of acrosome-intact sperm with that of fluorescence-labeled Pisum sativum agglutinin (PSA) probe, HS-13 monoclonal antibody can be routinely used for monitoring sperm capacitation and acrosome reaction.

Acrosome↗