IRON ABSORPTION FROM THE GASTRO-INTESTINAL TRACT

1962 ◽  
Vol 40 (1) ◽  
pp. 17-24 ◽  
Author(s):  
Shirley Cantrill ◽  
RJ Walsh
Blood ◽  
1961 ◽  
Vol 18 (6) ◽  
pp. 727-736 ◽  
Author(s):  
GERALD A. MENDEL

Abstract (1) Evidence is presented that the augmentation of iron absorption from the gastro-intestinal tract produced by hypoxia can occur independently of acceleration of erythropoiesis. (2) It is demonstrated that the hormone erythropoietin is capable of enhancing iron absorption; and that this property of erythropoietin is indirect, being dependent on acceleration of erythropoiesis. (3) An experimental model for the study of those factors that affect iron absorption and are independent of increased red cell production is presented.


1943 ◽  
Vol 78 (3) ◽  
pp. 169-188 ◽  
Author(s):  
P. F. Hahn ◽  
W. F. Bale ◽  
J. F. Ross ◽  
W. M. Balfour ◽  
G. H. Whipple

Iron absorption is a function of the gastro-intestinal mucosal epithelium. The normal non-anemic dog absorbs little iron but chronic anemia due to blood loss brings about considerable absorption—perhaps 5 to 15 times normal. In general the same differences are observed in man (1). Sudden change from normal to severe anemia within 24 hours does not significantly increase iron absorption. As the days pass new hemoglobin is formed. The body iron stores are depleted and within 7 days iron absorption is active, even when the red cell hematocrit is rising. Anoxemia of 50 per cent normal oxygen concentration for 48 hours does not significantly enhance iron absorption. In this respect it resembles acute anemia. Ordinary doses of iron given 1 to 6 hours before radio-iron will cause some "mucosa block"—that is an intake of radio-iron less than anticipated. Many variables which modify peristalsis come into this reaction. Iron given by vein some days before the dose of radio-iron does not appear to inhibit iron absorption. Plasma radio-iron absorption curves vary greatly. The curves may show sharp peaks in 1 to 2 hours when the iron is given in an empty stomach but after 6 hours when the radio-iron is given with food. Duration time of curves also varies widely, the plasma iron returning to normal in 6 to 12 hours. Gastric, duodenal, or jejunal pouches all show very active absorption of iron. The plasma concentration peak may reach a maximum before the solution of iron is removed from the gastric pouch—another example of "mucosa block." Absorption and distribution of radio-iron in the body of growing pups give very suggestive experimental data. The spleen, heart, upper gastro-intestinal tract, marrow, and pancreas show more radio-iron than was expected. The term "physiological saturation" with iron may be applied to the gastro-intestinal mucosal epithelium and explain one phase of acceptance or refusal of ingested iron. Desaturation is a matter of days not hours, whereas saturation may take place within 1 to 2 hours. We believe this change is a part of the complex protein metabolism of the cell.


2014 ◽  
Vol 9 (3) ◽  
pp. 196-204 ◽  
Author(s):  
Lucia Montenegro ◽  
Giuseppe Losurdo ◽  
Raffaele Licinio ◽  
Maria Zamparella ◽  
Floriana Giorgio ◽  
...  

2021 ◽  
Vol 9 (5) ◽  
pp. 1013
Author(s):  
Karina Arellano-Ayala ◽  
Juhwan Lim ◽  
Subin Yeo ◽  
Jorge Enrique Vazquez Bucheli ◽  
Svetoslav Dimitrov Todorov ◽  
...  

Preservation of probiotics by lyophilization is considered a method of choice for developing stable products. However, both direct consumption and reconstitution of dehydrated probiotic preparations before application “compromise” the survival and functional characteristics of the microorganisms under the stress of the upper gastro-intestinal tract. We evaluated the impact of different food additives on the viability, mucin adhesion, and zeta potential of a freeze-dried putative probiotic, Lactiplantibacillus (Lp.) plantarum HAC03. HAC03-compatible ingredients for the formulation of ten rehydration mixtures could be selected. Elevated efficacy was achieved by the B-active formulation, a mixture of non-protein nitrogen compounds, sugars, and salts. The survival of Lp. plantarum HAC03 increased by 36.36% compared rehydration with distilled water (4.92%) after passing simulated gastro-intestinal stress conditions. Cell viability determined by plate counting was confirmed by flow cytometry. B-active formulation also influenced Lp. plantarum HAC03 functionality by increasing its adherence to a Caco-2 cell-line and by changing the bacterial surface charge, measured as zeta potential.Hydrophobicity, mucin adhesion and immunomodulatory properties of Lp. plantarum HAC03 were not affected by the B-active formulation. The rehydration medium also effectively protected Lp. plantarum ATCC14917, Lp. plantarum 299v, Latilactobacillus sakei (Lt.) HAC11, Lacticaseibacillus (Lc.) paracasei 532, Enterococcus faecium 200, and Lc. rhamnosus BFE5263.


Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1824
Author(s):  
Giorgia Corazzola ◽  
Matteo Baini ◽  
Carla Grattarola ◽  
Cristina Panti ◽  
Federica Marcer ◽  
...  

Organs and content of the gastro-intestinal tract (GIT) of marine mammals are relevant for a variety of investigations and provide data to researchers from different fields. Currently used protocols applied to the GIT for specific analysis limit the possibility to execute other investigations and important information could be lost. To ensure a proper sample collection and a multidisciplinary investigation of the GIT of marine mammals, a new multi-sieves tool and a specific protocol have been developed. This new device and approach allowed the simultaneous sampling of the GIT and its content for the main investigations concerned. The samples collected during these preliminary trials were suitable to perform all the different research procedures considered in this work. The obtained results show that with a few and easy procedural adjustments, a multidisciplinary sampling and evaluation of the GIT of marine mammals is possible. This will reduce the risk of losing important data aimed at understanding the cause of death of the animal, but also biology and ecology of marine mammals, and other important data for their conservation and habitats management.


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