Biomedical subjects

A T Cheng

Publications and source records attributed to A T Cheng.

32 records · Page 2Linked to original sources

PubMed1997

Alcohol dehydrogenase and aldehyde dehydrogenase genotypes and alcoholism among Taiwanese aborigines.

Previous population association studies have indicated that certain alleles of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) genes may reduce the risk of alcoholism in Oriental populations. In this report we determined the genotypes for three genes, ADH2, ADH3, and ALDH2 among subjects with alcohol dependence (n = 159) and ethnically matched normal controls (n = 149) for the four largest aboriginal groups (Atayal, Ami, Bunun, and Paiwan) in Taiwan. The ethnicity matching used in this study was feasible because there are still few intergroup marriages between these aboriginal groups. On a group level, the rare frequencies of ALDH2*2, the inactive allele of ALDH2, among these aborigines may account partially for their vulnerability to alcohol use disorders. On an individual level, however, the genotypes controlling alcohol metabolism did not account for intragroup differences in vulnerability to alcoholism except in the case of ADH2 for the Ami ethnic group.

Adult↗

PubMed1997

Histopathologic changes after pericardial patch tracheoplasty.

Pericardial patch tracheoplasty has been used for surgical correction of long-segment congenital tracheal stenosis caused by complete tracheal rings in infants. The case histories of 2 infants with descriptions of the histopathologic changes in their respective tracheas are presented. Complete reepithelialization of the graft site with ciliated pseudostratified columnar epithelium was found, suggesting the likelihood of normal mucociliary flow in the trachea. The pericardial patches were replaced by mature scar tissue in the graft site, establishing a functional tracheal lumen. Wound healing in the trachea is reviewed. Obstruction by exuberant granulation tissue is an ongoing concern. Pericardium continues to be an important option as graft material for tracheal reconstruction in infants with long-segment congenital tracheal stenosis.

Abnormalities, Multiple↗

PubMed1997

Incidence of first onset alcoholism among Taiwanese aborigines.

BACKGROUND: An initial prevalence survey of mental disorders among 993 subjects aged 15 and above randomly drawn from four major Taiwanese aboriginal groups (the Atayal, Ami, Bunun and Paiwan) was conducted from 1986 to 1988. The incidence of alcoholism was investigated in a follow-up survey from 1990 to 1992. METHODS: Both surveys employed a semi-structured clinical interview with satisfactory reliability for case identification, and DSM-III-R as the diagnostic criteria for alcohol use disorders. The estimation of incidence rates of first onset alcoholism (alcohol abuse or dependence) was based on person-years at risk of 499 subjects who did not have any lifetime diagnosis of such morbidity at phase I. RESULTS: The follow-up rate was 99.6% and only four subjects among the survivors were not found. The age-standardized annual incidence rates of alcoholism ranged from 2.8 to 4.9% among the four aboriginal groups, and the rank order of rates was consistent with that of prevalences among these groups. The incidence rates of alcoholism were the highest among adolescents and young adults in men, and among the middle-aged in women. CONCLUSIONS: High rates of first onset alcoholism among the Taiwanese aborigines indicate an interaction of sociocultural and biological factors in the development of such morbidity.

Adolescent↗

PubMed1997

Personality disorder and suicide. A case-control study.

BACKGROUND: The relationships between personality disorders and suicide were investigated among two aboriginal groups and the Han Chinese in East Taiwan. METHOD: Biographical reconstructive interviews were conducted for consecutive suicides from each of the three ethnic groups (116 suicides in total), 113 of whom were matched with two controls for age, gender, and area of residence. RESULTS: In all three groups, a high proportion of suicides suffered from ICD-10 personality disorder before suicide (46.7-76.7%), and the most prevalent category was emotionally unstable personality disorder (F60.3) (26.7-56.7%). The risk for suicide was mainly significantly associated with F60.3, comorbidity among personality disorders, and comorbidity of personality disorder with other psychiatric disorders, particularly severe depression. CONCLUSION: The main category of personality disorder significantly associated with the risk of suicide is F60.3 in ICD-10. The risk is highest for a comorbidity of this category and severe depression.

Adult↗

PubMed1996

Alcoholism, hepatitis B and C viral infections, and impaired liver function among Taiwanese aboriginal groups.

Viral hepatitis and alcoholism prevail in four major Taiwanese aboriginal groups. To study the relative importance of the acquisition of hepatitis B virus or hepatitis C virus infection and alcoholism to the presence of impaired liver function in these groups, the authors conducted a semistructured clinical interview for alcoholism and test for seromarkers for viral hepatitis among 993 cohort members enrolled in 1990-1992 in an ongoing prospective study (Taiwan Aboriginal Study Project). The subjects' blood specimens were tested for serum alanine aminotransferase/aspartate aminotransferase levels and for the presence of hepatitis B surface antigen and anti-hepatitis C virus antibody. The prevalence of a combination of an alanine aminotransferase level of > 35 IU/liter and an aspartate aminotransferase level of > 40 IU/liter, implying impaired liver function or advanced liver disease, was 4.3% overall. Univariate and multiple logistic regression analysis showed that, rather than chronic hepatitis B virus infection, hepatitis C virus infection and alcoholism were the two dominant risk factors that signalled the risk of liver damage among these Taiwanese aborigines. In addition, these two contributing factors were able to act synergistically to cause impaired liver function.

Alcoholism↗

PubMed1996

Association of monoamine oxidase A alleles with alcoholism among male Chinese in Taiwan.

OBJECTIVE: The role of monoamine oxidase (MAO) in alcoholism was assessed by genetic association studies separately in five ethnic groups in Taiwan. METHOD: Restriction fragment length polymorphisms (RFLP) and dinucleotide repeat polymorphisms (DNRP) were used to determine MAOA and MAOB alleles in male alcoholic patients and nonalcoholic comparison subjects among Han Chinese and four aboriginal groups. RESULTS: Significant associations of alcohol dependence with MAOA alleles (RFLP and DNRP) were found among the Han Chinese, but not among the aboriginal groups. No significant association with MAOB DNRP alleles was found in any group. CONCLUSIONS: Genetic heterogeneity may underlie alcoholism among different ethnic groups in Taiwan, and MAOA mutations may play a role in susceptibility to alcoholism among Han Chinese.

Alcoholism↗

PubMed1996

Alcohol-metabolising genes and alcoholism among Taiwanese Han men: independent effect of ADH2, ADH3 and ALDH2.

BACKGROUND: Previous population association studies have indicated that certain alleles of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) may reduce the risk of alcoholism in Asian populations. The association of ALDH2 and ADH2 with the development of alcoholism was found to be independent of each other and has been replicated in different Asian populations, while the effect of ADH3 is less studied. METHOD: We genotyped the alcohol metabolism genes among Han men with alcohol dependence (n = 46) and their ethnically matched normal controls (n = 63) in Taiwan. Multiple logistic regression was then applied to assess the contribution of ADH3 to alcoholism by controlling the effect of ALDH2 and ADH2. RESULTS: The results of multivariate analyses demonstrated that the odds ratios for an increment of one allele of ADH2*1, ADH3*2 and ALDH2*1 in the development of alcoholism were 4.18, 3.82, and 6.89, respectively. CONCLUSIONS: These findings clearly indicate that all three alcohol-metabolising genes contribute to susceptibility to alcoholism.

Adult↗

PubMed1995

Mental illness and suicide. A case-control study in east Taiwan.

BACKGROUND: As part of the Taiwan Aboriginal Study Project, a case-control study of suicide among two aboriginal groups and the Han Chinese was carried out in East Taiwan. METHODS: Biographical reconstructive interviews were conducted for consecutive suicides from each of the three ethnic groups (a total of 116 suicides), 113 of whom were matched with two controls for age, sex, and area of residence. RESULTS: In all three groups, a high proportion of suicides suffered from mental illness before committing suicide (97% to 100%). The two most prevalent psychiatric disorders were depression and alcoholism, and the most common comorbid pattern was depression with substance use disorders. The risk for suicide was significantly associated with all of these psychiatric conditions, previous suicide attempts, and a family history of suicide and depression. Fifty-one percent of all suicides had consulted medical professionals in the previous month. CONCLUSION: Despite the widely different rates of depressive illness and alcoholism in different cultures previously reported, the psychiatric antecedents of suicide are the same in the West and the East.

Adolescent↗

PubMed1995

Development of a new scale for measuring acculturation: the Taiwan Aboriginal Acculturation Scale (TAAS).

As part of the Taiwan Aboriginal Study Project (TASP), a new acculturation scale (the Taiwan Aboriginal Acculturation Scale, or TAAS) has been developed among the aboriginal minorities of Austronesian origin in Taiwan. The design of the original 54 items was based on Milton Gordon's concept of assimilation in association with a careful consideration of cross-cultural validity. These items were administered to 144 subjects stratified by age and sex who were randomly sampled from four major Taiwanese aboriginal groups. Item analysis and factor analysis were applied to select an 18-item scale which has three subscales (factors): cultural assimilation, social assimilation, and social attitude. Results of validity and reliability studies of the TAAS were found to be acceptable. The development of TAAS demonstrates the applicability of the concept of acculturation as a process that involves changes both in attitude, and in behaviour, to non-western societies.

Acculturation↗

PubMed1995

Alcoholism among four aboriginal groups in Taiwan: high prevalences and their implications.

An epidemiological study of alcohol use disorders was conducted on population samples from four aboriginal groups in Taiwan (a total of 993 subjects). The survey involved ethnographic observation and a semistructured psychiatric interview. The interview covered a detailed symptom profile that allowed diagnoses to be made according to different diagnostic criteria. The lifetime prevalences of alcoholism according to the ICD-10 (research criteria) and the DSM-III-R criteria were found to be 42.2-54.7% and 44.2-55.5%, respectively, much higher than the rates found in an earlier study (0.11-0.16%) conducted 40 years ago. Men in all groups were found to have higher prevalences, a lower mean age at onset, and a longer mean duration (except in one group) of alcoholism than women. Differences in the distribution of sociodemographic correlates (age, sex, marital status, education, and ethnicity) of ICD-10 harmful use of alcohol and alcohol dependence were examined by case-control analysis with logistic regression. The lifetime prevalences of alcohol use disorders were higher than in recent epidemiological surveys conducted elsewhere. Possible biological and sociocultural explanations for the high prevalence of alcoholism among the study populations are discussed.

Acculturation↗

PubMed1992

Fine needle aspiration cytology: the Auckland experience.

Fine needle aspiration cytology is a widely recognized and yet sensitive technique which can provide diagnosis in lesions in the head and neck, enabling appropriate management plans for individual patients to be made. One hundred and eighty-seven fine needle aspirates from head and neck masses in 128 patients seen at Green Lane Hospital were studied. The ages ranged from 9 to 87 years with a median of 63 years. Ninety-five fine needle aspirates were of malignant lesions, mainly squamous cell carcinoma and lymphomas and 94 were nonmalignant. Comparisons were made between the fine needle aspirate cytology and the histological and clinical diagnosis. Overall, the sensitivity was 81%, specificity 89%, positive predictive value 91% and negative predictive value 78%. With respect to 72 lymph node aspirates there were no false positive values resulting in a sensitivity of 84%, specificity 100%, positive predictive value 100% and negative predictive value 65%. With respect to salivary gland lesions, there were no false positive or false negative fine needle aspirates. It was noted that diagnostic accuracy improved with experience and good communication between the cytopathologist and the clinician. Most of the non-diagnostic smears occurred during the early part of the study. The study confirms the useful application of fine needle aspiration cytology in managing head and neck disease appropriately.

Adolescent↗

PubMedDate not supplied

Inflammatory diseases of the ear.

The inflammatory diseases of external and middle ear are one of the commonest conditions encountered by the pediatric physician. Inner ear inflammations are less common and need special and urgent attention. Special management in each case requires detailed history, examination, necessary investigations and appropriate referral to otolaryngologist when necessary. The article is aimed to help formulate a plan in managing the inflammatory conditions of ear. Otalgia constitutes the most prominent of the symptoms in external and middle ear inflammations whereas vertigo, tinnitus and sensory hearing loss form the symptom complex for inner ear infections. It is necessary to understand the basic pathophysiology of the inflammatory condition to be able to institute a targetted treatment. The audiometry impedance studies, microbiology of discharge and occasionally ABR and CT scan from the mainstay of investigative workup. The treatment is specific and based on the precise diagnosis. It often requires the help of an otolaryngologist. Decisions may have to be made with regards to the need for any surgical intervention particularly in acute otitis media, an external canal abscess or an acute mastoiditis. A case of chronic otitis media with facial palsy or vertigo (labyrinthitis being a possibility) needs urgent intervention.

Child↗

PubMedDate not supplied

Middle ear effusion in children.

Acute otitis media (AOM) and otitis media with effusion (OME) in children can present with a variety of middle ear effusions (MEE). Even though the character of the effusion may vary, the underlying pathogenesis is often similar. In the last decade, there has been an abundance of new information in the fields of immunobiology and immunochemistry to explain the chronicity of MEE. There are also studies examining the efficacy of vaccination and immunoprophylaxis for recurrent AOM. Diagnosis of otitis media (OM) in a child can be difficult but good visualization by pneumatic otoscopy improves the accuracy of diagnosis of OME. The development of increasing bacterial resistance to antimicrobial therapy reinforces the need to be more rational in treating AOM and OME. The variability of the natural history and the long term sequelae of OME makes medical management more difficult. All children with chronic MEE should have audiologic evaluation. Surgery is recommended should the condition be refractory to medical therapy or if the complications of MEE develop.

Acute Disease↗

PubMedDate not supplied

In vitro antioxidant and photo-oxidant properties of dipyridamole.

The in vitro antioxidant and photo-oxidant activity of dipyridamole was studied by its effect on superoxide- and singlet oxygen-mediated photohemolysis and viability of neutrophils. Dipyridamole was found to be phototoxic when examined by the photohemolysis on human erythrocytes and on linoleic acid as lipid peroxidation model at concentrations above 3.0 x 10(-5) M. On the contrary, when lower concentrations (1.0 x 10(-5) to 1.0 x 10(-6) M) were used, dipyridamole showed a protector action against singlet oxygen-mediated photohemolysis by other phototoxic compounds like triamterene. This antioxidant property is proposed to result from quenching of triamterene mediated by fluorescence energy transfer. Auto-oxidation and fluorescence-energy transfer is clearly an important mechanism for protection for this drug.

Antioxidants↗