Hematopoietic Tissues

HEMATOPOIETIC TISSUES OLIVER P. JONES, PH.D. GROWTH OP LYMPH NODES, THYMUS AND SPLEEN, AND OUTPUT OF TH0RAcIc Duct LYMPHOCYTES IN THE NORMAL RAT. W. 0. Rcinhardt.’ Anat. Rec. 197-2.11, 2946. The results of studying growth of lymphoid tissues in 474 rats from birth to 19 months of age are very interesting, but most important for the hematologist are the data collected on the output of lymphocytes. Thoracic and cervical lymph ducts in 33 adult female rats were cannulated for varying periods and the lymph collected for cell count and volume studies. The total number of lymphocytes delivered to the blood stream per hour is about 9 million. This means that approximately io per cent of the total lymphocytes in the blood stream are replaced hourly. The entire lymphocyte population in the blood is replaced 2.05 times per day and the average life span of a lymphocyte in the blood stream is 12. hours. In this connection, it should be noted that following transfusions of cells labeled with acriflavine hydrochloride lymphocytes were found chiefly in the bone marrow (Farr: Anat. Rec. 94: 460, 1946). BLOOD TRANSFUSIONS AND BLOOD SUBSTITUTES EUGENE L. LOZNER, M.D. AMINO ACIDS IN THE PRODUCTION OF PLASMA PROTEIN AND NITROGEN BALANCE. S. C. Madden and G. H. Whipple.’ Am. J. M. Sc. iiz.’ 149-56, 1946. It is obvious from this and previous reports of Madden and his various co-workers that the ten essential amino acids may be given by mouth, vein, subcutaneously, or intraperitoneally and may maintain nitrogen and weight equilibrium in the dog. The observations reported herein include those on 3 patients in which amino acids were given intravenously, subcutaneously, and orally with favorable clinical results. Madden feels that amino acid mixtures are better tolerated parenterally and more palatable orally than protein hydrolysates. However, he points out that amino acids offer practical problems in large scale production and as yet are expensive. At the present moment they cannot be considered a significant therapeutic agent except in research laboratories. STUDIES ON TRAUMATIC SHOCK: V. THE TREATMENT OF CLINICAL SHOCK WITH GELATIN. E. I. Et’ans and H. S. Rafal.’ Ann. Surg. Ill.’ 478-94, 1945. Evans and Rafal in this article provide additional data in support of the increasingly evident conclusion that gelatin is a very useful substitute for plasma in situations where decreased plasma volume is present or is imminent. They have used both ‘lightly and heavily” degraded gelatin in traumatic shock and burn shock, and in these situations the lightly degraded gelatin appeared to be superior in that it was retained longer in the blood stream. They discuss the advantages and disadvantages briefly, and it may be well to repeat the disadvantages here. These consist of pseudo-agglutination of the red cells complicating blood grouping and cross matching (this may now be abolished by using a drop of i per cent glycine in the erythrocyto-serum-gelatin suspension); high viscosity which renders the gelatin solutions impossible to administer when cold (a 6 per cent gelatin solution must be kept at approximately 35#{176} C.); and the fact that gelatin does not supply any oxygen-carrying capacity, which may be important both in proper management in shock due to trauma and in burns. Thus, they point out that gelatin (as well as plasma) cannot be used as a true substitute for whole blood. This reviewer desires to call attention to two additional disadvantages, one the nutritional inferiority of gelatin as a protein and the other the fact that these gelatin solutions require especially careful preparation in order to produce a nonpyrogenic and uniform material. 358 For personal use only. on October 29, 2017. by guest www.bloodjournal.org From