Born with low birth weight in rural Southern India: what are the metabolic consequences 20 years later?

OBJECTIVE

Low birth weight (LBW) is common in the Indian population and may represent an important predisposing factor for type 2 diabetes (T2D) and the metabolic syndrome. Intensive metabolic examinations in ethnic LBW Asian Indians have been almost exclusively performed in immigrants living outside India. Therefore, we aimed to study the metabolic impact of being born with LBW in a rural non-migrant Indian population.

SUBJECTS AND METHODS

One hundred and seventeen non-migrant, young healthy men were recruited from a birth cohort in a rural part of south India. The subjects comprised 61 LBW and 56 normal birth weight (NBW) men, with NBW men acting as controls. Subjects underwent a hyperinsulinaemic euglycaemic clamp, i.v. and oral glucose tolerance tests and a dual-energy X-ray absorptiometry scan. The parents' anthropometric status and metabolic parameters were assessed.

RESULTS

Men with LBW were shorter (167±6.4 vs 172±6.0 cm, P<0.0001), lighter (51.9±9 vs 55.4±7 kg, P=0.02) and had a reduced lean body mass (42.1±5.4 vs 45.0±4.5 kg, P=0.002) compared with NBW controls. After adjustment for height and weight, the LBW subjects had increased diastolic blood pressure (77±6 vs 75±6 mmHg, P=0.01). Five LBW subjects had impaired glucose tolerance. In vivo insulin secretion and peripheral insulin action were similar in both the groups. Mothers of the LBW subjects were 3 cm shorter than the control mothers.

CONCLUSION

Only subtle features of the metabolic syndrome and changes in body composition among LBW rural Indians were found. Whether other factors such as urbanisation and ageing may unmask more severe metabolic abnormalities may require a long-term follow-up.

Strategy use, recall, and recall organization in young, middle-aged, and elderly adults

The application and transfer of free recall study strategies were examined for young, middle-aged, and elderly adults. Subjects were either instructed to use clustering and imagery, instructed to use their own study strategies, or given standard free recall instructions. Subjects at all age levels showed high initial use of categorization and low initial use of imagery. Subject-reported imagery increased after training, but categorization was the only strategy associated with higher recall levels. Training produced increases in recall clustering that were apparent only on a transfer list. The results provided evidence that adult age differences in memory occur even when middle-aged and elderly adults show evidence of categorization in recall.

Caries levels in patients with juvenile periodontitis

The degree and distribution of tooth decay in a group of juvenile periodontitis ( JP ) patients were compared with tooth decay in an age- and sex-matched periodontally normal control group. The experimental group was comprised of 13 patients of no more than 20 years of age who were designated as localized juvenile periodontitis patients ( LJP ) according to the definition of Baer, and 10 patients of no more than 25 years of age who were designated as generalized juvenile periodontitis patients ( GJP ), as described by Manson and Lehner . Twenty-three age- and sex-matched patients with no periodontal disease served as the control group. Caries was evaluated by standard clinical and radiographic criteria and quantitated by decayed, missing, filled teeth and surfaces (DMFS). Decay was further categorized as active proximal decay and as total proximal decay, which included both active proximal caries and restored proximal surfaces. A Student's t test revealed no statistical differences between the LJP and GJP groups. Moreover, there was no difference in the number of missing or filled teeth in the JP group as compared to the control group. However, 17 of the 23 JP patients had no proximal decay, whereas all but two of the 23 control patients had some proximal decay. Moreover, in the JP group ( LJP and GJP ) the mean values for active proximal decay and total proximal decay were both significantly lower than those in the control group (P less than 0.001). Thus, a low number of proximal carious lesions were found in the presence of juvenile periodontitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Specific antibodies to hemoglobin A1 (anti-Glu) and hemoglobin S (anti-Val) in the guinea pig: immunologic and structural correlations

Like goats and sheep, guinea pigs can produce, in response to human sickle cell hemoglobin (beta6 Glu leads to Val), an antibody population (anti-Val) that will bind sickle cell hemoglobin but not normal hemoglobin HbA. Unlike goats and sheep, guinea pigs can produce in response to human hemoglobin A1 an antibody fraction, anti-Glu, that will not react with human sickle cell hemoglobin. These anti-Glu antibodies have been isolated by affinity chromatography and their specificity confirmed by fluorescence-quenching titrations. The sequence of the first 10 amino acids of the beta-chain of guinea pig hemoglobin has been determined. This sequence differs from those of both hemoglobin HbA and sickle cell hemoglobin by two residues, those at positions 5 and 6. This explains the similarity of the immunogenicity of this site on the two human hemoglobins when administered to guinea pigs. Both goats and sheep are identical to hemoglobin A1 at the beta-6 position.

Idiotypic cross-reactivity between antibodies of different specificities

Cross-idiotypic specificity has been demonstrated between antibody populations of different specificities using antibodies directed toward human sickle cell hemoglobin (HbS). A site-specific antibody directed toward the beta6-position of HbS, anti-Val, was used to elicit an anti-idiotypic response in rabbits. Using this anti-idiotypic serum, idiotypic cross-reactivity was demonstrated between antibody populations that bind to human adult hemoglobin (HbA). It was demonstrated that in the case of the goat antibodies, these idiotypically cross-reacting antibodies are directed towards the beta6-position of the hemoglobin molecule. However, they differ in their specificity, binding to this site on HbA, whereas anti-Val binds only to HbS. The sheep antibody populations directed toward HbS differ qualitatively from those of the goat. Using rabbit anti-idiotypic serum specific for sheep anti-Val, cross-reactivity could be demonstrated with antibodies directed toward the alpha-chain of the hemoglobin molecule, as well as the beta-chain. There was also a low level of cross-reactivity with antibodies from a goat immunized with HbA.