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J A Ford

Publications and source records attributed to J A Ford.

At least 37 records · Page 2Linked to original sources

A possible relationship between high-extraction cereal and rickets and osteomalacia.

The evidence of the present study suggests a strong and possibly causal relationship between high-extraction cereal and rickets and osteomalacia. It seems likely that this occurs when vitamin-D status is border-line. The rachitogenic component of high-extraction cereal remains to be identified; dietary phytate now seems unlikely and phytate-derived polyphosphate esters or dietary phosphorus may be incriminated. The present study strongly indicates that Mellanby's original suggestion of an "anti-calcifying substance" in high-extraction cereal remains valid.

Adult↗

Prevention of vitamin-D deficiency in Asians.

Asian families living in Glasgow were studied between December, 1973, and June, 1974. One group of families served as a control; their mean serum-25-hydroxy-vitamin-D (25-hydroxy-cholecalciferol and 25-hydroxyergocalciferol) remained low, being 5-1 +/- 0-8 (S.E.M.) ng/ml at the end of the study. A second group was given 3000 units of vitamin D2 in a capsule weekly; this raised the mean concentration of 25-hydroxy-vitamin-D to 18-1 +/- 2-9 ng/ml. The variable effectiveness of this supplement was attributable to some subjects not taking the capsules regularly. The third group of families was provided with chupatty flour fortified with vitamin D(6000 units per kg). This increased mean serum-25-hydroxy-vitamin-D very uniformly to a mean value of 19-5 +/- 1-2 ng/ml. It is concluded that vitamin-D deficiency in Asian immigrants could be substantially reduced by fortification of chupatty flour with vitamin D.

Adolescent↗

Clinical and subclinical vitamin D deficiency in Bradford children.

A survey of the vitamin D status of Bradford schoolchildren was carried out in April 1973, employing conventional biochemistry, radiology, and measurement of 25-hydroxycholecalciferol levels. Biochemical evidence of rickets was present in 45% of the Asians. When re-examined in September, several children showed spontaneous biochemical resolution; nevertheless, radiological abnormalities were present in 12% of the original sample. No evidence of rickets was detected in the smaller White sample. Minor biochemical abnormalities were present in 9 of the 40 West Indian children. A study of admissions of Bradford hospitals in the 4 years 1969-1972 inclusive confirmed that clinical vitamin D deficiency was confined to Asians except for a few cases of infantile rickets in White children. The probability that one Asian child in 40 may require admission during the period from birth to adolescence emphasizes the urgent need for the introduction of prophylactic measures.

Adolescent↗

Cord gamma glutamyl transpeptidase activity and neonatal jaundice.

gamma Glutamyl transpeptidase (GGT) activity was measured in normal neonates and in maternal serum post partum. Levels were above the normal adult range (35I U/1) in all neonates and a significant correlation was bound between enzyme activity and bilirubin levels on day 7(P less than 0-005). The mean bilirubin level on days 4 and 7 was higher in babies with cord values less than 90 IU/1. In certain circumstances increased plasma GGT activity may serve as an index of enzyme induction. However, our results suggest that raised levels in the neonate may reflect hepatic microsomal damage with subsequent impairment of bilirubin conjugation. Further evaluative studies of cord GGT activity in neonates at risk, with a view to early prophylactic or therapeutic measures, are indicated.

Bilirubin↗

The insulin response to intravenous fructose in relation to blood glucose levels.

The insulinotropic action of intravenous fructose was examined in 24 subjects without known metabolic disease. When blood glucose values before the fructose infusion were at or below normal fasting levels, fructose elicited only a small plasma insulin response. In contrast, the insulin response was strikingly augmented when preinfusion blood glucose and plasma insulin levels were moderately elevated. The insulinotropic action of fructose appears closely related to the preinfusion blood glucose level. Fructose has little or no insulinotropic action in the absence of glucose but potentiates glucose-mediated insulin release. The insulinotropic potency of other glucose analogues in vivo may show a similar dependence on concomitant blood glucose levels.

Adult↗

Studies of vitamin D deficiency in man.

Highly sensitive assays have been developed that enable 25-hydroxycholecalciferol (25-hydroxyvitamin D3) and 25-hydroxyergocalciferol (25-hydroxyvitamin D2) to be measured in the same serum sample. With these assays it has been shown that endogenously produced cholecalciferol (vitamin D3) is important in man; the findings further emphasize the role of vitamin D metabolites as hormones rather than vitamins in the traditional sense. Dietary sources of vitamin D appear to be inadequate and vitamin D deficiency has been shown to the cause of rickets and osteomalacia in Asian immigrants to Britain. This condition may be readily treated with small doses of vitamin D. In addition, sub-clinical deficiency was found in the Asian community. In the elderly, also, vitamin D deficiency was established as an important cause of osteomalacia and again evidence for the existence of a sub-clinical deficiency state was found. It is therefore suggested that the present prophylactic practices should be reviewed. Secondary hyperparathyroidism (reflected by elevated concentrations of circulating immunoassayable parathyroid hormone) was shown to be the rule rather than the exception in vitamin D deficiency. Some patients, however, had failed to respond to a hypocalcaemic stimulus. In others, there were high concentrations of parathyroid hormone despite normal serum calcium concentrations. Thus the relationship between parathyroid hormone and metabolites of vitamin D may not be mediated through changes in serum calcium alone, and it is postulated that metabolites of vitamin D may directly affect the secretion of parathyroid hormone.

Adolescent↗