Long-Term Clearance of [57Co]Cyanocobalamin in Vegans and Pernicious Anaemia

1980 ◽  
Vol 58 (1) ◽  
pp. 101-103 ◽  
Author(s):  
S. Amin ◽  
T. Spinks ◽  
A. Ranicar ◽  
M. D. Short ◽  
A. V. Hoffbrand

1. Whole-body counting has been used to monitor the clearance of [57Co]cyanocobalamin in normal subjects, vegans and patients with pernicious anaemia. After oral administration of 57Colabelled cyanocobalamin (1 μg/l μCi), subjects were counted for radioactivity monthly for a maximum period of 1 year. 2. The results obtained were consistent with a monoexponential clearance model and a least-squares fit showed that there was no significant difference between the mean clearance rates for the vegans and normal subjects. 3. The patients with pernicious anaemia cleared the vitamin significantly more quickly than the normal control subjects. 4. This may be due to failure to reabsorb biliary vitamin B12 in pernicious anaemia because of the absence of intrinsic factor.

Blood ◽  
1961 ◽  
Vol 18 (1) ◽  
pp. 95-101 ◽  
Author(s):  
P. G. REIZENSTEIN ◽  
EUGENE P. CRONKITE ◽  
S. H. COHN

Abstract A technic is described to measure directly the intestinal absorption of radiovitamin B12 by using a whole-body gamma spectrometer. A double tracer technic is used, and the amounts of free and intrinsic factor bound vitamin B12, respectively, retained in the body after final excretion of unabsorbed radioactivity, are measured. The results are in agreement with those previously obtained by other methods. The present method is simple and quantitative. The primary advantage of the whole-body counter for measuring absorption of Cobalt-labeled B12 is that it can measure less than 0.1 µc. with a high degree of accuracy. Whole-body counting substitutes a rapid and simple measurement for the difficult and tedious collection and radiochemical analysis of excreta.


1994 ◽  
Vol 71 (2) ◽  
pp. 203-207 ◽  
Author(s):  
D. G. Maxton ◽  
R. P. H. Thompson ◽  
R. C. Hider

The absorption of 59Fe from preparations of FeSO4 and the ferric hydroxypyranone complexes maltol and ethyl maltol was studied by whole-body counting in normal subjects and patients with Fe deficiency. Fe in the Fe3+ complexes was in general absorbed almost as well as Fe2+. It is concluded that the absorption of Fe3+ from hydroxypyranone complexes is much greater than that from simple Fe3+ salts; this may prove an efficient and less toxic form of Fe for the treatment of deficiency.


1972 ◽  
Vol 43 (2) ◽  
pp. 233-250 ◽  
Author(s):  
J. F. Adams ◽  
D. J. Clow ◽  
Sheila K. Ross ◽  
K. Boddy ◽  
Priscilla King ◽  
...  

1. The absorption of radioactive cobalamin was measured by a whole-body counting technique in control subjects and in patients with pernicious anaemia. 2. The absorption of cyanocobalamin by patients with pernicious anaemia was decreased by charcoal but not by bile or saliva. 3. The absorption of cyanocobalamin by control subjects was not affected by food but was significantly increased by pentagastrin. With pentagastrin the absorption of cyanocobalamin was significantly greater than that of hydroxocobalamin. The hog intrinsic factor-mediated absorption of cyanocobalamin by patients with pernicious anaemia was significantly depressed by pentagastrin. 4. The effect of increasing the mass of hog intrinsic factor concentrate on the absorption of cyanocobalamin by patients with pernicious anaemia could be described by a function relating the amount absorbed, the mass of intrinsic factor and two constants. The relationship implies that when the mass of intrinsic factor is small the amount of cyanocobalamin absorbed is directly proportional to the mass of intrinsic factor but that absorption approaches a saturation value with increasing mass of intrinsic factor. In physiological terms the function implies that absorption is proportional to the amount of cyanocobalamin attached to receptor sites but that cyanocobalamin attached to receptor sites may become detached and either reattached or lost to absorption. 5. With oral doses of 25 μg and 50 μg, control subjects absorbed more cyanocobalamin and hydroxocobalamin than patients with pernicious anaemia. At both dose levels control subjects absorbed more cyanocobalamin than hydroxocobalamin but no difference was observed in patients with pernicious anaemia. The intrinsic factor mechanism therefore influences amounts absorbed at such dose levels and appears to be a factor in the differences in absorption of cyanocobalamin and hydroxocobalamin. 6. The use of double-tracer techniques makes it possible for each subject to act as his own control in studies of vitamin B12 absorption. The value of this technique is stressed.


1985 ◽  
Vol 54 (3) ◽  
pp. 585-592 ◽  
Author(s):  
Susan J. Fairweather-Tail ◽  
A. J. A. Wright

1. The availability of iron, zinc and calcium in a diet containing 400 g ‘fibre-filler’ (a mixture of bran, fruit and nuts, used in the F-plan diet)/kg diet (HF diet) was measured by whole-body counting in rats, using 59Fe, 66Zn and 47Ca as extrinsic labels, and compared with a diet of similar mineral content but no ‘fibre-filler’ (LF diet). Absorption of Fe and Ca was significantly higher from the HF than from the LF diet but there was no difference in Zn availability between the two diets.2. The ability of rats given LF or HF diets for 3 or 28 d to absorb Fe, Zn and Ca was measured using ferrous sulphate, zinc chloride and calcium chloride in a cooked starch-sucrose (1: 1 w/w) paste, extrinsically-labelled with the appropriate isotope. There was no difference in Fe absorption between the HF- and LF-fed groups but both Zn and Ca absorption were higher in LF- than in HF-fed animals after 3 and 28 d.3. The mineral status of the animals given HF or LF diets for 28 d was examined, and there were no differences in blood haemoglobin, liver and bone Zn and plasma and bone Ca levels. The total liver Fe was significantly lower (P < 0.05) in the HF-fed animals.4. It was concluded that ‘fibre-filler’did not have an adverse effect on Fe, Zn or Ca metabolism in rats although the long-term effect on Fe status warrants more detailed investigation. Further work is required to extend these studies to man.


1977 ◽  
Vol 16 (04) ◽  
pp. 163-167
Author(s):  
K. Bakos ◽  
Věra Wernischová

SummaryWhole-body counting makes an important contribution of radioisotope techniques to ȁEin vivo“ absorption studies, in comparison with other methods. In a large number of subjects, the method was tested for its usefulness in the diagnosis of calcium malabsorption. The effects of drugs, of the calcium load in the gut and of the whole-body content of calcium on the absorption process were studied in a control group.


1976 ◽  
Vol 15 (05) ◽  
pp. 246-247
Author(s):  
S. C. Jain ◽  
G. C. Bhola ◽  
A. Nagaratnam ◽  
M. M. Gupta

SummaryIn the Marinelli chair, a geometry widely used in whole body counting, the lower part of the leg is seen quite inefficiently by the detector. The present paper describes an attempt to modify the standard chair geometry to minimise this limitation. The subject sits crossed-legged in the “Buddha Posture” in the standard chair. Studies with humanoid phantoms and a volunteer sitting in the Buddha posture show that this modification brings marked improvement over the Marinelli chair both from the point of view of sensitivity and uniformity of spatial response.


1989 ◽  
Vol 26 (6) ◽  
pp. 455-461 ◽  
Author(s):  
K. J. Nikula ◽  
S. A. Benjamin ◽  
G. M. Angleton ◽  
A. C. Lee

Gross and light microscopic features of transitional cell carcinomas (TCC) of the urinary tract were examined in Beagle dogs used for the study of the long-term effects of low-dose, whole-body, 60Co gamma radiation. Thirty-eight cases of TCC occurred among 990 dogs that were from 0 to 14 years of age. There was no conclusive evidence of a radiation effect. The 38 TCC were equally divided between male and female dogs, but there was a significant difference in the sex distribution of urethra-origin TCC. Eleven males had a primary urethral TCC compared to only two females. There was no significant difference between the urethra-origin and bladder-origin TCCs in the number of tumors that caused clinical signs, metastasized, or that contributed to the death of the dog. All cases of urethral TCC in male dogs occurred in the prostatic urethra. The majority of these cases were not recognized to be neoplasms at gross necropsy, but microscopic examination revealed the TCC. Our findings differ from previous reports stating that TCC occurs more frequently in female than male dogs, and they especially differ from reports claiming that urethra-origin TCC is predominately a disease of female dogs.


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