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Biomedical subjects

J Hegenauer

Publications and source records attributed to J Hegenauer.

28 records · Page 2Linked to original sources
PubMed1977

A hydrostatic device for tissue dehydration.

A simple device for mixing water and organic solvents can be easily constructed to dehydrate tissue for electron microscopy. The device utilizes hydrostatic leveling between a reservoir and a mixing chamber to produce a continuously increasing concentration of dehydrating solvent. The rate of dehydration may be regulated by geometry and/or outflow rate. A prototype model is described which compactly incorporates the solvent reservoirs and a tissue tray that can accommodate ten tissue specimens in stainless steel mesh baskets. The device can be fabricated cheaply and replaces manual dehydration.

Desiccation↗
PubMed1975

Effect of milk and casein on the absorption of supplemental iron in the mouse and chick.

Milk is an attractive vehicle for introducing iron supplements into iron-deficient infants and children. This study compares the effects of milk and caseins on the whole-body absorption of radioactive iron complexes in an attempt to resolve the controversy over whether milk and its constituent phosphoproteins seriously impair iron absorption. Evidence is presented to clarify the role of the calcium-casein micelles of cow's milk in binding iron donated by the ferric-nitrilotriacetate (NTA) complex. The absorption of iron from isolated Fe(III)-casein complexes was studied in mice as a function of the casein--to--Fe ratio and was compared with the absorption of Fe(III)-NTA at equivalent levels. Even at casein--to--Fe ratios higher than those found in conventional iron-supplemented cow's milk (10-15 mg Fe/qt; casein P:Fe congruent to 34), absorption of iron(III) from the casein or NTA complex was not significantly different. There was no significant difference in the absorption of iron administered to mice and chicks as ferrous ion, ferric-NTA, or ferric fructose; nonfat cow's milk did not inhibit the absorption of these iron compounds. For the chick, in fact, milk significantly enhanced the absorption of iron from the ferric-NTA chelate. In order to affect iron absorption significantly casein would have to be present considerably in excess of that found in conventionally supplemented cow's milk.

Absorption↗
PubMedDate not supplied

Tired blood and rusty livers.

Iron deficiency is one of the most serious nutritional problems confronting the United States and the world today. An understanding of the mechanisms operative in the control of uptake and utilization of iron is essential to develop suitable prophylactic and therapeutic strategies. Iron excess can also be a serious health hazard. Studies on Bantu siderosis, hemochromatosis and other overload pathologies also provide insight into the intake and storage of this metal. Several models for iron transport across the mucosal membrane are developed. The most satisfactory seems to involve chelation of the iron to provide solubility diffusion passively across the gut membrane, and equilibrium binding to various storage sites within the tissue. Both ferric and ferrous forms are available. The solution chemistry of iron governs its biological behavior. Low-molecular-weight compounds present in normal dietary foodstuffs, as well as those prepared synthetically, can enhance the uptake of oral iron. Suitable application of complexes of iron with fructose, nitrilotriacetate, citrate and other molecules should be efficacious in the treatment of iron deficiency anemia. Potential dangers of food fortification with iron are acknowledged, and application of immunoassay techniques for measuring circulating ferritin suggest it as a rapid and inexpensive monitor for overload.

Alcoholism↗