William H. Crosby

Intraluminal biopsy of the small intestine; the intestinal biopsy capsule.

Summary1. An instrument for obtaining intraluminal biopsies of the intestinal mucosa has been described. It consists of a capsule containing a rotating knife which is spring-activated and triggered by suction. The suction first draws a bit of mucosa into the capsule before the knife is sprung. The capsule is held captive by a polyethylene tube 2 mm. in diameter, which also serves to transmit suction and to retrieve the capsule.2. Although the instrument was devised for jejunal biopsy it can be used to obtain specimens from any site between the oropharynx and the ileocecal valve.3. The method is safe and reliable. It is technically uncomplicated and it imposes a minimum of hardship on the subject.

The Absorption of Nonferrous Metals in Iron Deficiency

Abstract : The intestinal absorption of cobalt and manganese was increased in rats rendered iron deficient by bleeding and diet. The intestinal absorption of cesium, magnesium, mercury, calcium, and copper was not increased in rats consuming an iron-deficient diet but was unchanged in bled rats. (Author)

A cause of the thrombocytopenia and leukopenia that occur in dogs during deep hypothermia.

A previous report from this laboratory (1) presented the results of hematologic studies in nine dogs cooled below 200 C. During induction of hypothermia the animals showed a marked rise in red cell count, hemoglobin, and hematocrit, together with a nearly complete disappearance of white cells and platelets. On rewarming, the values all returned to normal. A number of studies have been carried out to learn more about the mechanism of these changes. The present paper describes some of the studies dealing especially with the changes in platelets and white cells. The experiments were performed on a group of 22 adult mongrel dogs. Hypothermia was induced by a method of surface cooling previously reported (2). Each dog was anesthetized with intravenous thiopental. An endotracheal catheter was inserted and connected to an automatic respirator utilizing room air. Thermo-couples in the rectum and esophagus permitted continuous temperature recordings by a Brown potentiometer. A continuous three limb lead electrocardiogram and aortic blood pressure were also recorded. The animal was placed in an ice bath at 40 C. and cooled until ven-tricular fibrillation occurred or the rectal temperature reached 170 C. The heart was defibrillated electrically. Each experiment, from the onset of hypothermia until rewarming had raised the body temperature to approximately 30° C., occupied approximately five hours. Platelet counts were carried out by the method of Brecher and Cronkite (3) using phase microscopy. Two pipettes were filled and two chambers for each pipette were counted and the average was taken as the result for each determination. By this technique, the normal range for platelet counts in dogs is 200,000 to 350,000 per cu. mm. Leukocyte counts were carried out by the standard hemocytometer technique using 1: 20 dilution. Both sides of two hemocytometer chambers were counted. Hemoglobin concentration was measured by the cyanmethemoglobin method (4). Hematocrit was measured in capillary tubes after high-speed centrifuga-tion (5). Protocol 1: Bone marrow aspirations and biopsies were carried out from the ribs and tibias of three dogs before, during, and after hypothermia. Protocol 2: Studies with radioactive platelets were carried out in dogs using a donor (Dog A) and a recipient (Dog B). Two mc. of Pa (NaHP0O, Abbott) was injected into Dog A. One week later, Dog A was bled by cardiac puncture, and 500 ml. of blood was drawn into a plastic bag containing disodium versinate solution. Simultaneously 500 ml. of blood was taken from …

Hemolytic anemia after open-heart repair of ostium-primum defects.

DESTRUCTION of red cells by mechanical battering during circulation may result in hemolytic reactions, with hemoglobinemia and, if severe enough, hemoglobinuria. Prolonged, strenuous exertion has provoked the syndrome,1 , 2 and it has recently occurred in two other situations associated with cardiovascular surgery: after the insertion of a lucite ball-valve prosthesis within the thoracic aorta3; and as a complication of cardiac repair after open-heart surgery.4 The purpose of this report is to present 2 further cases of the second syndrome illustrating two degrees of severity of hemolytic disease. Case Reports Case 1. A 17-year-old boy was admitted to Walter Reed General .xa0.xa0.

Regulation of the Intestinal Absorption of Iron by the Rate of Erythropoiesis

PREVIOUS experimental work suggests that the utibation of iron for erythropoiesis is more important than the state of iron stores in the regulation of gastrointestinal absorption of iron. This has been demonstrated by: (I) increased absorption of iron in the iron-loaded animal following acute blood loss despite the presence of excess iron stores (Bothwell, Pirzio-Biroli and Finch, 1958; Weintraub, Conrad and Crosby, 1964a); (2) fdure of the direct reduction of iron by partial hepatectomy to stimulate increased absorption of iron (Weintraub et al., 1964a); (3) increased absorption of iron in experimentally induced haemolytic anaemia in animals with normal to increased iron stores (Bothwell et al., 1958; Chapelle, Gabrio, Stevens and Finch, 1955) ; and (4) before iron absorption is increased following acute haemorrhage there is a 4-5 day lag (Bothwell et al., 1958; Hahn, Bale, Ross, Balfour and Whipple, 1943) which has been demonstrated to correlate with onset of an increased plasma iron turnover (Weintraub et al., 1964b). To confirm the role of erythropoiesis one must also demonstrate that states in which erythropoiesis is depressed and the iron stores are normal or decreased are associated with a decreased iron absorption. The present experiments attempt to demonstrate this phenomenon using animals with physiologically induced polycythaemia. Reduction of the atmospheric pressure increases the rate of erythropoiesis, and polycythaemia results. If after this state has been attained the animals are returned to normal atmospheric pressure the stimulus to erythropoiesis is removed. The increased red-cell mass which is now no longer needed acts to depress erythropoiesis (Huff, Lawrence, Siri, Wasserman and Hennessy, 195 I ; Reynafarje, Lozano and Valdivieso, 1959; Weintraub, Gordon and Camiscoli, 1963). During this stage we performed our studies.

Measurement of Total Body Iron59 in Animals Using Whole-Body Liquid Scintillation Detectors

Summary Iron absorption and total body retention was measured in rats using radio-iron59 and a whole-body liquid scintillation counter. Whole-body liquid scintillation counting provides an efficient and reliable method of assaying small quantities of γ-emitting nuclides in live animals and biologic specimens.

Absorption of hemoglobin iron by the rat.

Summary In the rat the absorption of a test dose of hemoglobin or hemin iron59 was significantly less than a comparable dose of iron59 as FeSO4. That this is of physiologic significance was demonstrated by producing a state of iron deficiency in animals raised on a diet with hemoglobin as the only source of iron, These findings are in contrast to recent observations in man and suggest a difference between species as well as a difference in the epithelial cells”ability to sequester iron as the salt or in the heme ring.

Iron Absorption: The Effect of an Iron-Deficient Diet

A diet deficient in iron causes a rapid, marked increase in iron absorption in rats. The increased absorption occurs in the absence of a significant change in iron stores as judged by the effect of an equivalent change in stores produced by phlebotomy, and in the absence of increased erythropoietic activity as judged by the rate of removal of iron-59 from the plasma.

The Effect of Dextran on Platelet Factor 3 Activity: In Vitro and In Vivo Studies

Intravenous infusions of one liter of low molecular weight and standard clinical dextran in normal adult subjects resulted in a significant alteration of platelet function as characterized by marked depression of platelet factor 3 (PF 3) activity. Disruption of the abnormal platelets by sonic oscillation corrected the defect, indicating that dextran coating of the platelets inhibited the release of PF 3 activity. These findings were confirmed by in vitro studies.

Red‐Cell Lipids in Various Abnormalities of the Human Red Cell

THE structure of red cells is sometimes obviously implicated in red-cell diseases, as in spherocytosis and sickle-cell anaemia. In other diseases other faults of red-cell structures may be implicit: the red cells may appear normal but provc incapable ofnormal survival; the marrow may be malfunctioiial as in leukaemia and polycythaemia Vera ; nutritional needs may iiiterfere with red-cell production; or environmental factors may damage the red cells after they have been properly constructed. The lipids of the human red cell are primarily structural, and they are coiiccntratcd at the surface of the cell in the so-called surface menibrane or red-cell envelope (Ponder, 1954). The present study was undertaken to learn if the red cells in various haematological disorders dcnionstrate any abnormality in the quantity or proportions of structural lipids.