Biomedical subjects

N A Tuan

Publications and source records attributed to N A Tuan.

4 recordsLinked to original sources

PubMed1994

Blood glucose distribution and prevalence of diabetes in Hanoi (Vietnam).

Few epidemiologic surveys have been performed to assess the prevalence of diabetes in representative samples, and few data are available on the epidemiologic features of diabetes in Southeast Asia. We report the results of a 1990 study performed in the Hanoi area (Vietnam) on 4,912 subjects (95.0% of the eligible population), aged 15 years or over, selected by a stratified random cluster procedure using the 1989 census list. A two-step design was used: 1) screening for diabetes by measuring capillary blood glucose (CBG) before dinner with a Glucometer II device; and 2) for subjects with a CBG measurement of > or = 105 mg/dl, a diagnostic test on the following morning, using a 75-g oral glucose tolerance test and World Health Organization criteria (93.9% of the positive screenees took this test). CBG values before dinner were unimodally distributed and skewed to the right, increasing with age in both sexes. Women had a significantly higher level of age-adjusted CBG than did men before dinner (p < 0.0001) as well as when fasting (p < 0.0001) and 2 hours after the oral glucose tolerance test (p = 0.013). The prevalence of diabetes was 1.2% (95% confidence interval (CI) 0.9-1.5) and of impaired glucose tolerance, 1.6% (95% CI 1.3-2.0). Women had a significantly higher age-adjusted prevalence of diabetes than did men (relative risk = 2.3; 95% CI 1.3-4.1). Of the 63 diabetic subjects, nine (14.3%) had been diagnosed before the study, only one was obviously insulin dependent, and only one was obese with a body mass index of > or = 27 kg/m2. The subjects living in the urban areas had higher levels of fasting and 2-hour CBG and a higher diabetes prevalence than did the rural inhabitants (relative risk = 1.3; 95% CI 1.04-3.23). Diabetes appears to be a rare disease in the Hanoi area (1.4% for subjects aged 30-64 years, after age standardization using the Segi distribution), affecting women two times as often as men. Typical insulin-dependent (type I) or obese non-insulin-dependent (type II) diabetes mellitus patients are uncommon.

Adolescent↗

PubMed1991

Differences in the complement activation induced by preformed and nascent immune complexes.

While preformed BSA-anti-BSA immune complexes (PIC) bind efficiently to human RBC after their interaction with human complement, nascent BSA-anti-BSA immune complexes (NIC) formed in the presence of complement do not bind to autologous RBC. The same results were obtained with tetanus toxoid-anti-tetanus toxoid PIC and NIC. In order to elucidate the causes of this marked difference between the RBC-binding properties of PIC and NIC, the profile of complement activation induced by them was compared using haemolytic assays and sensitive ELISA tests. BSA-anti-BSA NIC activated C1 more efficiently than PIC. This was reflected in a higher C4 content of the isolated NIC and higher C1 INH-C1s and lower C1q-fibronectin complex level in the NIC-treated serum as compared to the PIC-treated ones. Although isolated NIC contained more C3 than isolated PIC did, there was no significant difference in the AP activation. These findings suggest that the failure of NIC to bind to RBC is not due to a lack of C4-binding, or C3-binding and/or activation, but rather to the special structure of this type of complex.

Antigen-Antibody Complex↗

PubMed1989

Skin test responsiveness to a series of new tuberculins of children living in three Vietnamese cities.

A skin test survey was conducted among 1035 children aged 7-19 years living in three cities in Vietnam. Fifteen new tuberculins, including leprosin-A, were applied; an induration of 2 mm diameter or more was considered positive. Compared to some other tropical countries, low levels of sensitisation were recorded and remarkable regional differences were found. Positivity to any tuberculins (pooled data) among non-BCG-vaccinated children was significantly lower in Hanoi (13.1%) and HoChiMinh-City [HCMC] (15.5%) than in Nha Trang (25.7%) [p = 0.001 and p = 0.012, respectively]. The proportion of non-vaccinated children responding to Tuberculin ranged from 18.4% in Hanoi to 54.5% in Nha Trang. Leprosin-A elicited a response in 14.9% of the children in Nha Trang, but in very few of those in Hanoi (4.3%) or HCMC (3.0%). Thus, of the three cities studied, significant sensitisation to both M. tuberculosis and M. leprae was demonstrable only in Nha Trang. In Hanoi most of the response was to fast-growing species whilst in HCMC and Nha Trang it was mainly to slow-growing species. These results may account in part for the observed differences in the prevalence of tuberculosis and leprosy between the north and the south of Vietnam.

Adolescent↗

PubMedDate not supplied

Clinical evaluation of lentil lectin-reactive alpha-fetoprotein-L3 in histology-proven hepatocellular carcinoma.

INTRODUCTION: Serum alpha-fetoprotein (AFP) is a useful marker of hepatocellular carcinoma (HCC), although the serum AFP concentration is also increased in patients with chronic liver diseases (CLD). The analysis of AFP glycoforms has been known to be of diagnostic value. We applied the lectin-affinity electrophoresis and antibody-affinity blotting techniques to HCC patients in Vietnam in order to better understand the role of lentil lectin-affinity AFP-L3 in the diagnosis and differential diagnosis of HCC, and its relationship with the biological characteristics of HCC. METHODS: Lens culinaris agglutinin-reactive AFP (AFP-L3) was measured in 65 patients with histologically proven HCC and 25 patients with CLD. All patients had serum AFP levels above 54 ng/mL. AFP-L3 levels were determined by lectin affinity electrophoresis coupled with antibody-affinity blotting. The diagnosis of HCC was confirmed histologically by ultrasound-guided biopsy. RESULTS: The mean value of AFP-L3 in the HCC patients was 49.6 +/- 21.6%, which was significantly higher (p<0.001) than that in the 25 CLD patients (10.7 +/- 4.3%). When the cutoff level for AFP-L3 was set at 15% (mean +/- SD), the sensitivity was 96.9%, the specificity 92.0% and the accuracy 95.5% in the 65 HCC patients. There was no clear correlation between serum AFP level and AFP-L3 percentage (r=0.16). There was no correlation between AFP-L3 and the maximum diameter of HCC nodules (r=0.05). However, the mean AFP-L3 value was higher in moderately or poorly differentiated HCC than in well differentiated tumors (p<0.001). CONCLUSIONS: AFP-L3 is potentially a clinically useful marker for the differentiation of increased AFP levels in hepatocellular carcinoma and chronic liver diseases. The AFP-L3 percentage is closely related to HCC differentiation. We consider the analysis of AFP-L3 a useful adjunct in the diagnosis of HCC.

Adult↗