No abstract

The effects of platelet counts, hematocrit, and leukocyte counts were studied on the closure times of the Thrombostat 4000 (in-vitro bleeding time, IVBT). Closure times became longer with platelet counts <50 x 10'!L; an inverse linear correlation could be established. Hematocrit was also inversely correlated with the closure time. At constant platelet counts a hematocrit of 55% yielded an immediate closure of the filter, while with a hematocrit <15% no closure times could be measured. At constant platelet counts and hematocrits, nomonuclear and polymorphonuclear leukocytes also inDuenced closure times; increased counts resulted in shorter closure times. Leukocytes from a patient with chronic myelocytic leukemia had the same effects.

At the present time there is an enormously increasing demand for albumin. The most common procedure for the isolation of this plasma component is the cold ethanol technique developed by Cohn. Because this process necessarily isolates other blood components for which there is less demand in relation to albumin, albumin production is expensive. Therefore, we have developed a two-step fractionation for the isolation of albumin. It is basically a heat precipitation method with the albumin yield being about 90% of the original plasma albumin. In comparison to cold ethanol methods, it is considerably less expensive. Other blood components, e.g., clotting factors, immunoglobulins, may also be isolated. A nonmodified gamma-globulin for intravenous use is obtained by removing anti-complementary activity with hydroxyethyl starch. Additional fractionation steps are required to isolate these other components, but unlike in established methods, these are not necessary for the isolation of solely albumin.

Thrombosis of the left subclavian vein occurred in a 44-year-old man. It was found to be caused by an atypical thymus carcinoid of the anterior mediastinum without carcinoid syndrome. Primary resection was not possible, but it was removed after three cycles of neoadjuvant chemotherapy with doxorubicin, cisplatin, vincristine and cyclophosphamide. Increased concentrations of alkaline phosphatase and parathormone were then noted. Subtotal parathyroidectomy revealed hyperplastic parathyroids. A gastrinoma was suspected from a history of peptic ulcer for many years which had persisted despite a Billroth II gastric resection 10 years ago. Serum gastrin, analysis of gastric secretion and a secretin-stimulating test confirmed the diagnosis. Recurrent episodes of weakness and syncope, in the presence of low blood sugar levels and a positive C-peptide suppression test, were interpreted as due to an insulinoma. There was no evidence of increased hypophyseal or adrenal function. Finally, in the absence of a family history, multiple endocrine neoplasia type 1 (MEN 1) was diagnosed with co-existing primary hyperparathyroidism, gastrinoma, insulinoma and thymus carcinoid. Somatostatin-receptor scintigraphy provided localization of the MEN 1 with enrichment in the thorax and abdomen.

Human plasma may be separated into five fractions using the method described by Cohn in 1946. Although there are several drawbacks to alcohol precipitation, especially in albumin isolation, it is still used throughout the world. This paper describes an alternative procedure for albumin isolation from plasma or albumin-containing plasma fractions using a combined heat fraction/polyethylene glycol precipitation method. No polyethylene glycol is detected in the final product which is immunoelectrophoretically 100% pure, salt poor, heat resistant during pasteurization, and stable during long-term room temperature storage. The yield is at least 90% of the original plasma albumin. In comparison with the Cohn method, fractionation time and expense are significantly reduced.