The assay of folic-acid activity of liver

Bennett, Myra C.; Berry, Valerie; Chanarin, I.; Ardeman, S.

doi:10.1136/jcp.17.1.27

Cited by 26 publications

(9 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Section: Discussionmentioning

confidence: 99%

“…Preliminary studies of methodology were carried out as described elsewhere (Bennett, Berry, Chanarin, and Ardeman, 1964). These showed that the maximum values were obtained in the case of human liver when 1 part of liver was homogenized and heated in 500 parts of 1% potassium ascorbate buffer at pH 6.…”

Section: -0 4-5 Preparation Of Liver Sample For Folate Assaymentioning

confidence: 99%

“…These tests are the urinary excretion of formiminoglutamic acid and the direct assay of the serum (or whole blood) concentration of various forms of folate by microbiological assay. Results with these tests have been reviewed in a recent symposium at the Royal Society of Medicine (Herbert, 1964;Chanarin, 1964).Abnormal results with both these tests are frequent in hospital patients who are haematologically normal, and it is uncertain whether these abnormal values indicate subclinical folate deficiency or merely the unsatisfactory nature of the tests. The purpose of this study was to correlate the results of these tests of folic-acid function with direct assay of the amount of folic acid in the tissues.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Hepatic Folate in Man

Chanarin¹,

Hutchinson²,

McLean³

et al. 1966

BMJ

Self Cite

View full text Add to dashboard Cite

Ionizing Radiation-Hems 2,249 persons were all exposed to 5 rads, and in practice their exposure was on average much lower, the exposed group would still be less than 20% of the minimum size (in man-years) to permit detection of radiation-induced leukaemia and an even smaller fraction of the size (in man-generations) required for detection of a mutation attributable to the increased radiation. Summary and ConclusionsIn order to detect radiation effects by a population study it is, of course, essential that the population be large enough for the radiation effects to be statistically significant. For exposure of man to low doses of radiation at low dose rates the minimum population size to permit detection of radiation-induced leukaemia is many tens of thousands of man-years; for detection of dominant mutations attributable to the increased radiation the necessary population (in man-generations), as estimated from mouse data, is even larger. Exposed populations which have been surveyed so far are smaller than the minimum theoretical size and would need to be studied for an impracticably long time before either a mutation attributable to the increased radiation at a single locus or radiation-induced leukaemia could be detected. Stevenson (1957), in his examination of this problem, also concluded that it appeared unlikely that populations could be found of sufficient size to permit detection of mutations induced by background radiation.In conclusion it should be emphasized that, in addition to the difficulty of fulfilling the requirement for a minimum population size, if a population study were undertaken to detect radiation effects additional practical problems are fikely to be encountered in setting up a satisfactory control population (Griinberg, 1964) Medicine (Herbert, 1964;Chanarin, 1964). Abnormal results with both these tests are frequent in hospital patients who are haematologically normal, and it is uncertain whether these abnormal values indicate subclinical folate deficiency or merely the unsatisfactory nature of the tests. The purpose of this study was to correlate the results of these tests of folic-acid function with direct assay of the amount of folic acid in the tissues. The liver is the most satisfactory tissue for this purpose, since it contains most of the folates in the body and is the site of the important synthetic reactions involving the folate coenzymes. Donaldson and Keresztesy (1959) have found that hepatic folate in the horse is 5-methyltetrahydropteroyl-monoglutamate. This paper also reports observations on the nature of the folate compounds in human liver. Materials and MethodsObservations were made on 26 patients admitted to the surgical wards with a variety of disorders (see Table), and who were all undergoing a laparotomy. The day before operation a blood sample was obtained for a full blood count, including enumeration of five-lobed neutrophils, and for the microbiological assay of the levels of serum folate and vitamin B12' Fifteen grammes of 1-histidine-mono-HCl was given orall...

show abstract

Section: Discussionmentioning

confidence: 99%

Section: -0 4-5 Preparation Of Liver Sample For Folate Assaymentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Hepatic Folate in Man

Chanarin¹,

Hutchinson²,

McLean³

et al. 1966

BMJ

Self Cite

View full text Add to dashboard Cite

show abstract

“…Though substances such as thymidine may replace the folate requirement for L. casei this is not an important factor in the assay of biological material and foodstuffs. Thus a folate-free diet results in almost complete dis-appearance of growth-promoting material from rat liver for L. casei, indicating that other substances are not present in such material in sufficient amount to overcome the need for folate (Bennett et al, 1964). The availability to man of the two forms of folate termed "free" and "polyglutamate" is not known.…”

Section: Discussionmentioning

confidence: 99%

Normal dietary folate, iron, and protein intake, with particular reference to pregnancy.

Chanarin¹,

Rothman²,

Perry³

et al. 1968

BMJ

Self Cite

View full text Add to dashboard Cite

“…The liver folic acid levels were assayed by the method of Bennett et a/. (9) by placing a portion of homogenized liver in media without folk acid to a standardized concentration of 10% (w/v). Commercially prepared Folic Acid Casei Medium was used (Difco Laboratories, Detroit, Mich.).…”

mentioning

confidence: 99%

Effects of Folic Acid Malnutrition on Rotaviral Infection in Mice

Morrey¹,

Sidwell²,

Noble³

et al. 1984

Experimental Biology and Medicine

View full text Add to dashboard Cite

A study was undertaken to determine if dietary deficiencies of folic acid would influence rotaviral diarrheal disease in infant mice. Female mice were fed diets containing essentially no folic acid, 25% of a normal quantity of folic acid, or a normally recommended quantity of folic acid, beginning at time of breeding and continuing through periods of gestation and lactation. Two-day-old infants from these dams were exposed to purified murine rotavirus or to sterile virus diluent and the severity of the rotaviral infection monitored. Infants from the low folk acid group had significantly lower folate levels in their livers, indicating a deficiency was achieved, and developed more severe disease manifestations than those infants from the dams receiving the normal folic acid levels in their diet. The infection enhancement was seen as increased incidences of diarrhea and a significantly greater number of mice exhibiting high intestinal rotaviral antigen titers. Serum rotavirus antibody titers were below detectable levels in a significant number of these same infants. 77

show abstract

The assay of folic-acid activity of liver

Cited by 26 publications

References 7 publications

Hepatic Folate in Man

Hepatic Folate in Man

Normal dietary folate, iron, and protein intake, with particular reference to pregnancy.

Effects of Folic Acid Malnutrition on Rotaviral Infection in Mice

Contact Info

Product

Resources

About