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Biomedical subjects

J L Tsai

Publications and source records attributed to J L Tsai.

At least 19 recordsLinked to original sources
PubMed2002

The chelating treatment is not useful in human's intoxication with acute herbicidal organic arsenic.

The clinical manifestations of acute organic arsenic intoxication in humans have seldom been described and the associated treatment has been thought to be the same as that of acute inorganic arsenic intoxication. We have studied a collection of patients from 1996 to 2001 who called the Poison Control Center of Kaohsiung Medical University Hospital asking for information regarding acute organic arsenic intoxication. The 17 patients ranged in age from 23 to 64 years old, with 5 females and 12 males. The cause of arsenic ingestion was attempted suicide. Abdominal pain and vomiting were the main symptoms. There were no differences in results between patients treated with and those treated without chelating agents. We therefore believe that the results of acute organic intoxication are not same as acute inorganic intoxication and it is unnecessary to use chelating agents in such conditions.

Acute Disease↗
PubMed2002

Determination of urinary beryllium, arsenic, and selenium in steel production workers.

Some of the most pernicious dangers of pollution arise from the presence of traces of toxic elements in the environment. In this work, we report on the determination of beryllium, arsenic, and selenium in the urine of steel production and steel quality control (QC) workers, in comparison to healthy control subjects. The urine samples were digested by a microwave system. Graphite furnace and hydride atomic absorption was used for the quantitative measurements of Be and As and Se, respectively. A quality control method for these procedures was established with concurrent analysis of Standard Trace Metals 7879 Level II and NIST SRM 2670 (Toxic Elements in Freeze Dried Urine). The results show that the urinary levels of these elements in steel production (As, 38.1 +/- 28.7 microg/L; Be, 1.58 +/- 0.46 microg/L, and Se, 69.2 +/- 28.8 +/- g/L) and in quality control workers (As, 23.9 +/- 18.1 microg/L; Be, 1.58 +/- 0.46 microg/L, and Se, 54.8 +/- 25.1 microg/L) are significantly higher than in the controls (As, 10.3 +/- 8.7 microg/L; Be, 0.83 +/- 0.46 microg/L; and Se, 32.3 +/- 13.5 microg/L). The possible connection of these elements with the etiology of disease and the possible role of selenium as a protective agent against the oncogenic and teratogenic action of other substances is discussed. We suggest the need for improvement of environmental conditions in the workplace through better ventilation and industrial hygiene practices.

Arsenic↗
PubMed2001

Liquid crystalline polysiloxane polymer as stationary phase in gas chromatography capillary column for the separation of dioxin/furan compounds.

A side-chain liquid crystalline polysiloxane polymer (PS3DBDE1) with high purity and high isotropic transition temperature served as a stationary phase in an attempt to chromatographize the dioxin/furan compounds. The polymer was coated on the inner surface of a 0.25 mm I.D. capillary column by using the static coating method, forming a film with a thickness of df approximately 0.25 microm. A commercial standard solution (US EPA 1613 standard solution 1613CS4) containing polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) was used to test the chromatographic behavior of the laboratory-made capillary column. Two commercial capillary columns HP-5MS (Hewlett-Packard) and RTX-5MS (RTX) were chosen to compare their chromatographic behavior. The results show that by the use of PS3DBDE1 the isomeric pair compounds 1,2,3,4-TeCDD vs. 2,3,7,8-TeCDD and 1,2,3,4,7,8-HxCDD vs. 1,2,3,6,7,8-HxCDD and the same substituted-chlorine number compounds 1,2,3,4,6,7,8-HpCDF vs. 1,2.3,4,6,7,8-HpCDD and 1,2,3,4,6,7,8,9-OCDD vs. 1,2,3,4,6,7,8,9-OCDF had higher resolution than HP-5MS and RTX-5MS as suggested by the column makers.

Chromatography, Gas↗
PubMed2001

A pilot evaluation of tibia lead concentrations in Taiwan.

BACKGROUND: The aims of this study were to examine some of the factors that influence tibia lead concentrations, tibia lead x-ray fluorescence measurement uncertainty and blood lead concentrations, and to compare tibia lead concentrations in Taiwanese lead workers to those observed in lead workers from other countries. METHODS: A pilot evaluation of 43 adult lead workers who underwent measurements of tibia lead and blood lead concentrations. RESULTS: Mean and maximum tibia lead concentrations were 54 microg of Pb per g of bone mineral(microg/g) and 193 microg/g, respectively. Mean and maximum blood lead concentrations were 44 microg/dl and 92 microg/dl, respectively. CONCLUSION: Past occupational control of lead exposure in Taiwan, ROC, did not prevent these workers from accumulating tibia lead concentrations greater than those in similar workers elsewhere in the world.

Adolescent↗
PubMed2001

Relationship of young adult Chinese Americans with their parents: variation by migratory status and cultural orientation.

To examine whether Chinese and American cultural orientations mediate the association between migratory status and parent relationship, 122 American-born, 121 early-immigrant, and 110 late-immigrant Chinese young adults were measured on cultural orientation and parent relationship. The poorest relationships were found in the early-immigrant group. Cultural orientation mediated the difference in parent relationship between early and late immigrant groups, but not between early-immigrant and American-born groups. Implications of the findings for research and practice are discussed.

Adult↗
PubMed2001

Asian American college students as model minorities: an examination of their overall competence.

Educational success among Asian Americans has led to their being labeled the "model minority." At the University of California, Berkeley (UCB), Asian American students have higher grade point averages (GPAs) than Hispanic and African American but not White students, supporting the notion that Asian Americans are more successful compared with other racial minorities. However, success in the classroom does not implicate effective functioning in life, and nonacademic criteria ought to be considered in assessing the validity of the model minority image. Given the increasing diversification of the United States, cross-racial engagement may be an additional contributor to overall competence. This was empirically tested in a group of 642 undergraduates at UCB, including 291 Asian, 197 White, 20 African American, 67 Hispanic, and 56 multiracial students. Overall competence was operationalized by sense of coherence, that is, the extent to which the world is experienced as comprehensible, manageable, and meaningful (A. Antonovsky, 1979, 1987). As predicted, Asian Americans had significantly fewer numbers of cross-racial groups represented in their friendship network than did students of all other races. Lower cross-racial engagement and being Asian (as compared with White) were related to a lower sense of coherence, whereas lower GPA was not. Within the Asian American subsample, cross-racial engagement was again significantly associated with greater coherence, whereas GPA again was not. Thus, extending the definition of success to overall competence, these findings raise questions about the applicability of the model minority label to Asian Americans, despite their academic achievement. Future studies need to assess the reasons for their limited cross-racial engagement and lower sense of coherence and to examine means to assist the development of these strengths.

Achievement↗
PubMed2001

Cultural predictors of self-esteem: a study of Chinese American female and male young adults.

This study examined how specific domains of cultural orientation (language, social affiliation, and cultural pride) related to self-esteem for a sample of 174 Chinese American male and 179 Chinese American female college students. Participants completed measures of cultural orientation (General Ethnicity Questionnaire; J.L. Tsai, Y.W. Ying, & P.A. Lee, 2000) and self-esteem (M. Rosenberg, 1965). Cultural orientation significantly predicted self-esteem, above and beyond the contribution of age, gender, grade point average, and socioeconomic status. Specifically, proficiency in English and Chinese languages and pride in Chinese culture were positively correlated with self-esteem, whereas affiliation with Chinese people was negatively correlated with selfesteem. The cultural predictors of self-esteem differed for Chinese American men and women. Whereas self-esteem was mainly related to pride in Chinese culture for Chinese American women, self-esteem was mainly related to English and Chinese language proficiency for Chinese American men. Implications of these findings for understanding Asian Americans are discussed.

Adult↗
PubMed2001

A multichannel PC tachistoscope with high resolution and fast display change capability.

The number of channels that PC tachistoscopes can have has increased recently (Bokhorst, 1995; Myors, 1998); however, neither the quality of display nor speed of image switching has been improved. This article shows the capability of VESA's VBE 3.0 standard (1998) for increasing the number of channels of high-quality images. And the refresh rate can be set to the fastest cathode ray tube (CRT) scanning rate the monitor can tolerate in order to reduce the timing delay of changing display. A PCTSCOPE library was written in C to provide these capabilities, which is compatible with conventional DOS real mode. The PC tachistoscope can have numbers of channels with various resolutions and colors and different refresh rates. For example, 25 images with the resolution of 640 x 480 pixels and 256 colors can be loaded to video memory, and vertical refresh rate can be set to 180 Hz. It takes less than 6 msec to change the display among 25 channels in synchronizing with the start of the video scanning frame. In this library, the number of channels, the resolution of the images, and the speed of changing display all are improved. The multichannel PC tachistoscope with this technique is especially suitable for research requiring high-quality images and rapid successive presentation of stimuli.

Computer Storage Devices↗
PubMed2001

Molecular subtyping of Shigella flexneri 3a isolates by plasmid profile analysis and pulsed-field gel electrophoresis.

Twenty-two clinical isolates of Shigella flexneri 3a that were obtained from stool specimens from seven outbreaks of infection in northern Taiwan were subtyped and compared using plasmid profile analysis and pulsed-field gel electrophoresis (PFGE). Among 32 isolates, three distinct patterns were found by plasmid profile analysis and six by PFGE, with three different restriction enzymes, XbaI, SfiI, or NotI. Seven PFGE patterns were observed in a comparative analysis using a combination of these three enzymes. Isolates collected from the same outbreaks had the same PFGE combination patterns and were distinguishable from those obtained during other outbreaks. These findings suggest that PFGE may be the most powerful method of genotyping S. flexneri 3a in epidemiological studies.

Electrophoresis, Gel, Pulsed-Field↗
PubMed2001

Two episodes of ethylene oxide poisoning--a case report.

Ethylene oxide is used as a sterilizer, a solvent, a plasticizer and in the manufacture of special solvents, antifreeze, polyester resins and non-ionic surfactants. Its toxicity is caused by an alkylating reaction with most organic substances in the body. Four workers, without any protection, managed the leakage of ethylene oxide from the collecting tank improperly on July 29, 2000. In the same factory, the overflow of ethylene oxide in process resulted in leakage of ethylene oxide again on Aug. 7, 2000. Two workers were poisoned despite wearing full-face respirators with ethylene oxide approved canisters. In these two events, the workers all smelled an ether-like odor. Six workers experienced nausea, vomiting, chest tightness, shortness of breath, dizziness, cough and ocular irritation. One worker had transient loss of consciousness. Oxygen therapy and supportive care were used. Patients were discharged in stable condition. The permissible exposure limit of ethylene oxide in air is 1 ppm as an eight hour TWA. Above 50 ppm, the odor threshold, a positive-pressure supplied air respirator is needed to protect the worker. Full-face respirators with ethylene oxide approved canisters could not protect our cases who smelled the odor and were exposed to an unknown concentration. It is important to wear positive-pressure self-contained breathing apparatuses equipped with full facepieces to clean up the contamination area and rescue the patients.

Adult↗
PubMed2000

Qualitative determination of urinary morphine by capillary zone electrophoresis and ion trap mass spectrometry.

A rapid, sensitive method for the determination of morphine and amphetamine was developed using capillary zone electrophoresis coupled with electrospray interface (ESI), ion-trap tandem mass spectrometry (CE-ESI-MS2). Morphine and amphetamine were separated in 20 mM ammonium acetate buffer (pH 6.6) and detected by ion-trap mass detector in different analytical time segments (0-6.25 min for amphetamine and 6.25-12.0 min for morphine) in which the tune file for each compound was used separately. Molecular ions of morphine (m/z 286) and amphetamine (m/z 136) were detected at 5.77 and 6.83 min, respectively, while product ions of MS2 for each compound (m/z 229, 201 for morphine and m/z 119 for amphetamine) were detected almost exactly at the same time with their parent compounds. The limits of detection (LOD) for MS2 determination were 30 and 50 ng/mL for amphetamine and morphine, respectively, with an S/N ratio of 3. For more sensitive detection of morphine, the sample was injected for a longer time (i.e., 80 s) and hydrodynamically transported into a CE capillary for MS detection. Morphine and its product ion appear at 0.36 and 0.39 min on the ion chromatogram, respectively, with a five-fold increase of detection sensitivity (LOD, 10 ng/mL). The CE-MS system thus established was further applied for forensic urine samples screened as morphine-positive by fluorescence polarization immunoassay (FPIA). These results indicated the feasibility of CE-ESI-MS2 for confirmative testing of morphine in urine sample.

Amphetamine↗
PubMed2000

Autonomic, subjective, and expressive responses to emotional films in older and younger Chinese Americans and European Americans.

Previously, the authors found that during idiosyncratic emotional events (relived emotions, discussions about marital conflict), older European American adults demonstrated smaller changes in cardiovascular responding than their younger counterparts (R. W. Levenson, L. L. Carstensen, W. V. Friesen, & P. Ekman, 1991; R. W. Levenson, L. L. Carstensen, & J. M. Gottman, 1994). This study examined whether such differences held when the emotional events were standardized, and whether they extend to another cultural group. Forty-eight old (70-85 years) and 48 young (20-34 years) European Americans and Chinese Americans viewed sad and amusing film clips in the laboratory while their cardiovascular, subjective (online and retrospective), and behavioral responses were measured. Consistent with previous findings, older participants evidenced smaller changes in cardiovascular responding than did younger participants during the film clips. Consistent with earlier reports, old and young participants did not differ in most subjective and behavioral responses to the films. No cultural differences were found.

Adult↗
PubMed2000

The conception of depression in Chinese American college students.

The conception of depression in Chinese American college students was examined with the Center for Epidemiologic Studies--Depression Scale (CES-D). It was hypothesized that, because of their significant engagement with mainstream American culture, these students' conception of depression would better approximate White Americans' differentiated view (L. Radloff, 1977) than the general Chinese American community's integrated view (Y. Ying, 1988). A total of 353 bicultural Chinese American college students participated in the study. Consistent with the hypothesis, principal-components factor analysis with varimax rotation revealed a factor structure and loading similar to that found in White American adults. Confirmatory factor analysis also showed Chinese American college students to better approximate Radloff's differentiated model based on her White American samples than Ying's integrated model based on her Chinese American community sample. Implications of the findings and directions for future research are discussed.

Acculturation↗
PubMed2000

Absence of maternal A3243G mtDNA mutation and reversible hyperglycemia in a patient with MELAS syndrome.

We report the unusual features of a female patient who had MELAS-specific A3243G mutation in mitochondrial DNA (mtDNA) and diabetes mellitus (DM). The patient showed mitochondrial myopathy, encephalopathy, lactic acidosis, and deafness but lacked the stroke-like episode. Acute hyperglycemia was noted after one attack of status epilepticus. Molecular genetic analysis demonstrated a heteroplasmic A3243G point mutation in the mtDNAs of muscle, blood cells and hair follicles. Glucagon stimulation test exhibited marked depression of pancreatic beta-cell function. However, in a further study neither this mutation, nor MELAS syndrome or DM, was found in all of her maternal relatives. A series of follow-up studies for beta-cell function also showed gradual improvement. The pedigree study led us to believe that this A3243G mutation arose from the germ line cells or occurred later in somatic tissues of the patient. We also suggest that the A3243G mutation of mtDNA may elicit the pathogenesis of a subtype of DM. Nevertheless, environmental stress may be another important factor for provocation of the disease.

Adult↗
PubMed1999

Analysis of morphine and morphine-3beta-D glucuronide in human urine by capillary zone electrophoresis with minimal sample pretreatment.

The presence of two of the metabolites of heroin, free morphine and morphine 3-beta-D-glucuronide (MO3G) in acidified urine samples was simultaneously determined by capillary zone electrophoresis (CZE). In a run buffer containing 50 mM sodium borate and 250 mM boric acid (pH 8.6), free morphine migrates before a group of neutral compounds (peak N) in urine, which move with the velocity of electro-osmotic flow. In contrast, the glucuronidated form is negatively charged and migrates behind peak N. Both analytes can be precisely identified within their respective analytical window by their migration time with respect to peak N. The on-line multi-wavelengths scanning of the peak permits further confirmation. The detection sensitivity of both analytes was increased three-four fold if the samples were introduced with electro-injection as compared with hydrodynamic injection. Limits of detection (LOD) of free and conjugated morphine using electro-injection were 200 ng/mL and 500 ng/mL, respectively, determined at a 3:1 signal to noise ratio. A dramatic increase of free morphine was observed after acid hydrolysis of the urine concomitantly with the decrease of the glucuronidated form. We conclude that CZE is a rapid, simple, sensitive and useful screening technique for detection of heroin metabolites in the urine.

Calibration↗
PubMed1999

Determination of urinary arsenic, mercury, and selenium in steel production workers.

The fumes and dust of trace elements and their compounds are very toxic and have been related to an increase in the incidence of diseases. Occupational exposure to toxic metals and metalloids can be determined by means of workplace air measurements and biological monitoring. The aim of our investigation was to determine the concentrations of As, Hg, and Se in urine samples under routine clinical laboratory conditions. To assess the reliability of these methods, critical factors such as detection limit(s), calibration range(s), cost, accuracy, and precision were studied. The method was employed for the quantitative determination of arsenic, mercury, and selenium in urine samples from steel production and quality control workers and healthy unexposed controls. After pretreatment with acids, the samples were digested by means of a microwave oven. Arsenic was determined by hydride atomic absorption spectrometry and mercury was determined by cold vapor atomic absorption spectrometry, whereas selenium was determined by a graphite furnace atomic absorption spectrometry. The results indicate those urinary arsenic, mercury, and selenium levels of the exposed workers are significantly higher than those of the controls. The possibility that these elements are involved in the etiology of diseases is discussed and recommendations are made to improve workplace ventilation and industrial hygiene practices.

Arsenic↗
PubMed1999

Determinants of parental decisions on 'drop out' from cancer treatment for childhood cancer patients.

Little is known about the psychosocial process of parental decisions on 'drop out' from cancer treatment for paediatric patients in Taiwan. This study, based on structured in-depth interviews, attempted to document the determinants of parental decisions on drop out. A total of 19 parents of paediatric cancer patients who dropped out from a cancer treatment for at least a month within 3 years since first treatment were interviewed. Content analysis of qualitative data revealed six categories of determinants associated with parental decisions: suffering severe pain from medical treatments and adverse side-effects; desire for better and less painful treatments; adverse effect of other patients' experiences; searching for possible explanations for disease after prolonged denial of diagnosis; lack of empathy from health care professionals; and misinterpretation of improved prognostics. These findings reflected the deficiency of psychological and emotional support for parents from health care professionals prior to and during cancer treatment.

Adult↗