A Method for Determining the Oxidation State of Uranium at Concentration as Low AS 1010M

ABSTRACTThis paper describes the development and testing of a chemical procedure for determining the tetravalent and hexava-lent states of uranium in aqueous media at concentration as low as 10−10M. Results show the U(IV) stability towards fast modifications of the pH of the solution with oxygen free hydrochloric acid. Some results on the oxidation kinetic of the uranium tetravalent state versus the HCl and uranium concentrations as well as the Fe(III) content are presented.

A study of gastric secretion induced by close arterial infusions of histamine in the dog

The effects of close arterial infusions of progressively increasing quantities of histamine into different regions of a denervated total stomach pouch were compared with the effects of infusions of histamine into the splenic vein in dogs under chloralose–urethane anesthesia. Infusions of 0.5 mg/h and 2.0 mg/h of histamine into the left gastric artery (lesser curvature of the stomach) were more effective than were the infusions of the same solutions into the gastrosplenic artery (greater curvature) as shown by the shorter latency to the appearance of free HCl and by a greater volume of secretion and total acid output per square centimeter of mucosa. Infusions of excessive quantities of histamine (32.0 mg/h) resulted in a reversible inhibition of HCl output as observed on the lesser curvature. The peptic activity of the gastric juice was low and decreased progressively with increasing amounts of infused histamine. Systemic blood histamine concentrations did not change during infusions of 0.5 mg/h or 2.0 mg/h of histamine into the gastric arteries or splenic vein; infusions of larger amounts of histamine (8.0 mg/h and 32.0 mg/h) resulted in a penetration of histamine into the general circulation and in systemic effects. These effects appeared earlier and with smaller quantities of histamine when the latter was infused into the portal vein close to the liver than when administered into the splenic vein as judged by the appearance of free hydrochloric acid in the gastric contents.

Impaired Response to Iron Dextran Infusion Due to Latent Vitamin B12 Deficiency without Achlorhydria

A case of severe iron-deficiency anaemia as a result of intractable menorrhagia is described. Following treatment with an iron dextran infusion, an impaired haematological response occurred; this was shown to be the result of vitamin B12 deficiency despite the presence of abundant free hydrochloric acid in the gastric juice. The severe anaemia (3.5 g. %) was corrected within 5 weeks by one iron dextran infusion and vitamin B12 therapy prior to hysterectomy.

A Case of Juvenile Pernicious Anemia: Study of the Effects of Folic Acid and Vitamin B12

Observations on a 4-year-old boy with Addisonian pernicious anemia have been presented. Noteworthy clinical features included the onset of glossitis at the age of 4 months, followed by anemia severe enough to require hospitalization at the age of 1 year. Relapse occurred in the absence of specific therapy with vitamin B12 and was completely unaffected by the administration of folic acid. Studies with radioactive vitamin B12 demonstrated that almost all of the compound administered by mouth was unabsorbed and was recovered in the stools. When the vitamin was given simultaneously with a concentrate of intrinsic factor, however, approximately 70 per cent was absorbed. Furthermore, the child’s gastric juice, when mixed with radioactive vitamin B12 and fed to an adult with pernicious anemia in relapse, failed to enhance the latter’s absorption of the vitamin. The failure of our patient to absorb the vitamin alone, but his ability to do so when it was administered with intrinsic factor concentrate, was also confirmed by the "Schilling test," in which a proportion of the absorbed radioactive vitamin was "flushed" into the urine by parenteral injection of one milligram of conventional vitamin B12. Of special interest was the occurrence in the urine of an unidentified derivative of tetrahydrofolic acid, derived from orally administered pteroylglutamic acid. The presence of this compound in the urine was demonstrated chromatographically when the patient was critically ill with his disease prior to treatment with vitamin B12. Subsequent to therapy with vitamin B12, while the administration of folic acid was continued, the abnormal metabolite of folic acid could not be found in the urine. Similarly, the administration of folic acid did not lead to the appearance of this metabolite in the urine at a time when, after more than two years without specific therapy, a hematological relapse occurred that was much less severe than that previously observed. The implications of these observations, with respect to the metabolic interrelationships of folic acid and vitamin B12, are discussed. Of further interest were the findings of strongly acid gastric juice containing much mucus and free hydrochloric acid. A fairly normal gastric mucosa was demonstrated by biopsy. The meaning of these unusual findings is discussed and an hypothesis to account for them is offered. The probable sequence of events in these patients from childhood to the development of anemia, usually in later life, is set forth.

Pernicious Anemia without Gastric Atrophy and in the Presence of Free Hydrochloric Acid

A case is described of Addisonian pernicious anemia in a girl aged 16 years, associated with a normal gastric mucosa and free hydrochloric acid in the stomach. Partial, but significant deficiency of intrinsic factor activity was demonstrated in her gastric juice by the use of Co56-labeled vitamin B12.

Some Aspects of the Metabolism of Antimegaloblastic Substances in Man

1. When the sera of pernicious anemia patients or controls were heated at 100 C. for 30 minutes, they developed the ability to support the growth of L. leichmannii by virtue of some substance other than vitamin B12. It seemed likely, however, that following the administration of the vitamin, such heating also liberated free B12 in the serum from a combined form. 2. The L. leichmannii assay did not appear to be satisfactory for showing possible difference in the levels of vitamin B12 in the urines or sera of pernicious anemia patients and controls. 3. Parenterally administered vitamin B12 did not cause any measurable rise in the serum level of folic acid or citrovorum factor in pernicious anemia patients or controls. 4. The synthetic folic acid conjugates pteroyldiglutamic acid and pteroyltriglutamic acid appeared in the sera and urines of pernicious anemia patients as pteroylglutamic acid or some related substance with folic acid activity for S. faecalis. 5. Orally administered citrovorum factor appeared to be largely converted by the gastric juice to folic acid if free hydrochloric acid was present. When administered parenterally, however, citrovorum factor was excreted in the urine largely unchanged.