Impact evaluation of iron & iodine fortified salt.

As a novel approach to tackle the problems of iron deficiency anaemia and iodine deficiency disorders (IDDs), which often coexist, the National Institute of Nutrition has developed iron and iodine fortified common salt (double fortified salt-DFS) as a public health measure. This salt has undergone a battery of laboratory and field tests to evaluate its feasibility for use in a national programme. The DFS is designed to provide 1 mg of iron and 15 micrograms of iodine per gram of common salt. This was made possible by the inclusion of a polyphosphate stabilizer, sodium hexametaphosphate (SHMP) at 1 per cent level. The stability of iron and iodine was found to be good up to 6 months. However, the stability of iodine depended upon the quality of the salt used for fortification. The biological effects of long-term consumption of DFS were evaluated in experimental rats and in field trials. Both iron and iodine from the salt were found to be biologically available in regenerating haemoglobin and in increasing excretion of iodine in urine. When this salt was tested in tribal villages endemic for goitre and iron deficiency anaemia, the bioresponse was good with regard to the iodine status but was not uniform in all segments with regard to iron, probably due to confounding variables. In a study carried out in residential school children where such variables did not exist, DFS was found to have significant impact on haemoglobin status in anaemic children and improved their urinary iodine excretion. The consumption of DFS for 2 yr did not have any adverse effects in school children as well as in the tribal population. Parameters related to calcium homeostasis were not altered in children receiving DFS. Histopathological examination of tissues and radiological examination of bone did not reveal any abnormality in DFS fed rats. Similarly serum and urinary parameters related to calcium and phosphorus were not altered in DFS fed rats. Therefore, DFS is presented as a feasible and effective strategy to control the double deficiency of iron and iodine in our community.

Biological efficacy and plasma norethisterone levels of orally administered norethisterone enanthate in rat and hamster.

Norethisterone enanthate (NET-En) is a well known intramuscular contraceptive drug. The long acting nature of this preparation when administered orally was evaluated in female rats and hamsters using fertility inhibition test and from the plasma levels of norethisterone (NET). An oral dose of 20-60 mg NET-En was administered to random groups of six female rats and hamsters and were mated after five and ten days with males of proven fertility. The fertility inhibition rate was determined from vaginal delivery. A dose-dependent reduction in fertility was seen in rats 5 days after oral administration of NET-En. This effect was found to be less pronounced and not significant 10 days after administration of similar doses of NET-En. In hamsters, a similar but less pronounced effect was noted. The decrease in fertility was significant only at the 60 mg dose. The plasma levels of NET estimated by RIA over a period of 15 days, in a different set of treated rats, suggested rapid absorption of NET-En within a day, and drug concentration decreased slowly, the levels on the 4th day ranged from 0.9-2.3 with the 10 mg and 1.0-4.0 ng/ml with the 20 mg dose. Detection of adequate levels of NET in plasma during the estrous cycle in rats, and the fertility inhibition observed in female rats and at higher doses in hamsters, suggest that NET-En is orally active.

Protective effects of antioxidant enzymes and GSH in vivo on iron mediated lipid peroxidation in gastrointestinal tract of rat.

The protective mechanisms operating in the gastrointestinal (GI) tract to counteract the potential oxidizing effects of excess free iron, was tested in rats fed with excess iron. The activities of some antioxidant enzymes, the levels of GSH and the extent of lipid peroxidation at the site of iron absorption were measured. Based on the amount of thiobarbituric acid reactive substances (TBARS) produced, it could be deduced that the duodenal segment of GI tract is resistant to iron mediated lipid peroxidation. The duodenal function as judged from the activities of marker enzymes, namely, alkaline phosphatase and Lys-Ala-dipeptidyl aminopeptidase was normal. There was depletion of GSH possibly due to the increased activities of Cu, Zn SOD and catalase. However, the activity of Gpx was decreased in the Fe fed group. It was also observed that the ratios of SOD/Gpx and Cat/Gpx had significantly increased in the treated group whereas SOD/Cat remained constant suggesting that antioxidative enzymes play a key role in rendering the intestinal mucosal cells resistant to iron induced oxidative damage in rats.

A direct ELISA technique to detect antibodies against polioviruses.

A direct ELISA test was developed to detect circulating antibodies specific to poliovirus types 1, 2 and 3. Specificity of the test was established by using known polio negative and positive sera. The assay was compared with the standard microneutralization test using sera from polio and non polio cases vaccinated and unvaccinated subjects and standard positive sera obtained from WHO/EPI (Geneva). The reproducibility of the results was tested using different batches of the antigen prepared from Sabin strain of poliovirus supplied by ERC Bombay and from Sabin strain of virus obtained from WHO/EPI. ELISA was found to be as sensitive as microneutralization test in detecting seronegatives and was found to be specific to polio by giving negative results with non polio cases. ELISA is thus a rapid and simple method that may be useful for mapping seroepidemiology of poliomyelitis and as a tool for effective surveillance of the disease by offering rapid diagnosis in acute cases.

Evaluation of national nutritional anemia prophylaxis programme.

An evaluation of the National Nutritional Anemia Prophylaxis Program was carried out in Andhra Pradesh. About 8,000 respondents from about 5,754 households were interviewed and 487 pregnant women were covered for haemoglobin estimation in six selected districts. Nearly 19 per cent of the pregnant women had received folifer tablets, while about 1 per cent of child beneficiaries were receiving the tablets. The acceptance of the programme by the community appeared to be satisfactory. The reasons for poor coverage were reported to be inadequate and irregular supplies. Results indicated that the health functionaries were not properly oriented towards the programme, as many of them were not aware of all the beneficiaries under the programme. Chemical analysis of the tablets indicated that about 30 per cent of the tablet samples had iron content less than the expected levels, and none of them had expected levels of folic acid content.