Biomedical subjects

W M Wan Nazaimoon

Publications and source records attributed to W M Wan Nazaimoon.

4 recordsLinked to original sources

PubMed1996

Effects of iodine deficiency on insulin-like growth factor-I, insulin-like growth factor-binding protein-3 levels and height attainment in malnourished children.

OBJECTIVE: The expression and synthesis of IGF-I and IGFBP-3 have been shown to be regulated by hormones and nutrition. We study the effects of malnutrition and iodine deficiency on these growth factors and the height attainment of a group of children. DESIGN: We measured serum IGF-I and IGFBP-3 levels in a group of Malaysian aborigine children from three jungle settlements; Sinderut and Pos Lanai are known for iodine deficiency and endemic goitre, and Gombak is an iodine replete area with better socioeconomic status. PATIENTS: A total of 246 children were studied, 188 in the age group 4-10 years and 88 in the age group 11-15 years. MEASUREMENTS: All children were assessed anthropometrically and height standard deviation score (SDS) were calculated using the CDC Anthropometric Software package. Malnutrition was confirmed clinically and according to the WHO definition of malnutrition. IGF-I and IGFBP-3 were determined by radioimmunoassay, and T4 and TSH by immunoradiometric assay. RESULTS: Based on the height SDS, Sinderut and Pos Lanai children were significantly more malnourished and stunted than the Gombak children P = 0.0001). T4 levels were significantly lower (P = 0.0001) amongst the 4-10-years old Sinderut (81 +/- 2 nmol/l) than in Pos Lanai (101 +/- 3 nmol/l) or Gombak (123 +/- 3 nmol/l) children. Similar findings were also seen in the older children; mean T4 levels of those from Sinderut and Pos Lanai (83 +/- 3 and 88 +/- 4 nmol/l respectively), were low (P = 0.0001) compared to Gombak (118 +/- 3 nmol/l). Conversely, TSH levels in both age groups of Sinderut children were significantly elevated (P = 0.0001) (3.5 +/- 0.2 and 3.9 +/- 0.3 mU/l respectively) compared to age-matched groups from Pos Lanal (2.1 +/- 0.1 and 2.2 +/- 0.2 mU/l respectively) and Gombak (1.5 +/- 0.1 and 1.5 +/- 0.2 mU/l respectively). IGF-I and IGFBP-3 correlated significantly with the height SDS of the children, In both the 4-10 (r = 0.400, P = 0.0001 and r = 0.365, P = 0.0001 respectively) and 11-15 years age groups (r = 0.324, P = 0.002 and r = 0.533, P = 0.0001 respectively). Correlation between IGFBP-3 and T4 levels was more significant in the younger children (r = 0.412, P = 0.0001). Association between IGF-I and T4 levels was significant only in the 4-10 years age group (r = 0.237, P = 0.001). CONCLUSIONS: Varying duration and degree of exposure to malnutrition and iodine deficiency resulted in different mean levels of T4, TSH, IGF-I and IGFBP-3 in the three areas. The strong positive associations between IGF-I and IGFBP-3 levels and height SDS suggest that these biochemical measurements are indeed useful indicators of growth and nutritional status in children. The significant correlations between T4 and IGFBP-3 and IGF-1 suggests the importance of thyroid hormones in regulating the synthesis of these growth factors. The age-related increase of these growth factors even amongst malnourished, iodine deficient children implies that age-matched reference ranges are essential for proper evaluation of laboratory results.

Adolescent↗

PubMed1994

Thyroid function and pubertal development in malnutrition.

Thyroid function and pubertal development of aborigines (Orang Asli) and Malays at different socioeconomic strata were assessed among 1136 subjects aged 7 years and above. Anthropometric measurements, goitre and pubertal staging were done. Serum thyroxine (T4), triiodothyronine (T3) and growth hormone were measured using radioimmunoassays (RIA) and serum thyroid stimulating hormone (TSH) by immunoradiometric assays (IRMA). It was found that serum T3 in children was significantly higher in Malays from rural areas, girls and children aged less than 13 years. However, in adults, T3 was significantly associated with anthropometric indices. On the contrary, serum T4 levels were higher among children from urban areas. In adults, serum T4 levels were significantly related to nutritional status and they increased according to the levels of social development, being lowest in remote areas and highest in urban areas. However, serum TSH levels were significantly higher in Orang Asli at all ages and among malnourished children. By using multiple regression, apart from age, gender and ethnicity, nutritional status was a significant predictor for T3 levels in children and adults. Presence of goitre was an important factor which determined the T4 levels in children and adults after controlling for other factors. It was also a predictor for TSH levels in children but not in adults. Fasting serum growth hormone (GH) levels were significantly higher among less privileged groups and decreased according to social development. Serum growth hormone was negatively correlated with anthropometric indices and had a significant association with malnutrition.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

Serum thyroid stimulating hormone (TSH) in malnutrition: preliminary results.

This is a report of a cross sectional study involving 3 groups of children, moderately malnourished (BMI < 15), mildly malnourished (BMI 15-18) and well nourished (BMI > 18) to determine the differences in hormonal and biochemical parameters between the groups. The children were of age range from 7-17 years old. The children were from the same area with exposure to the same food, drinking water and environment. There were significant differences in the nutritional indices between the three groups. No differences were observed in levels of triiodothyronine (T3), thyroxine (T4) and T3:T4 ratio. Significant difference however was found in the TSH levels using highly sensitive IRMA TSH assays. Moderately malnourished children had higher TSH levels (p < 0.05) compared to mildly malnourished and well-nourished children. No difference was found between the mildly malnourished and well-nourished groups. There were no significant differences in serum cortisols done at similar times, fasting growth hormone and calcium. Serum alanine transminase (ALT) however was higher in moderately malnourished than in well-nourished children. Thus using highly sensitive IRMA TSH assays, we were able to detect differences in TSH levels even though T3, T4 and T3:T4 ratio, cortisol, growth hormone and calcium were normal, implying in moderately malnourished children, a higher TSH drive to maintain euthyroid state.

Adolescent↗

PubMed1990

Development of an in-house radioimmunoassay for human growth hormone.

A simple and sensitive double-antibody radioimmunoassay for human growth hormone (HGH) was developed, optimised and validated. The anti-hGH sera raised in 2 rabbits were highly specific with low cross-reactions of 0.19% and 0.3% with human placental lactogen and 0.21% and 0.13% with human prolactin. The mean sensitivity of the assay determined from 28 assays was found to be 0.4 +/- 0.2 mIU/L. Mean recovery of added exogenous hGH was 98.8 +/- 6.8%. Linearity studies of samples diluted at 1:2, 1:4 and 1:8 gave values of 101.3 +/- 5.3%, 109.6 +/- 13.4% and 97.3 +/- 13% respectively of those expected. The reproducibility of the assay was good; within assay coefficient of variation for serum samples with GH concentrations of 2.7, 13.6 and 28.2 mU/l ranged from 5.1 to 8.3% while the inter-assay precision varied from 4.9 to 10.3%. The in-house assay showed good correlation (r = 0.96, p less than 0.001) with a commercial HGH RIA kit (Dainabot, Japan). A reference normal adult fasting GH level of less than 7 mIU/l was established from 95 samples assayed by this method.

Animals↗