Divalent cation regulation of the surface orientation of platelet membrane glycoprotein IIb. Correlation with fibrinogen binding function and definition of a novel variant of Glanzmann's thrombasthenia

An antiplatelet monoclonal antibody, PMI-1, reacts with glycoproteins (GP) GPIIb, free GPIIb, and the GPIIb-IIIa complex. This antibody binds to 40,900 sites per platelet, with a Kd = 0.95 microM, and its binding is inhibited by the presence of magnesium or calcium in the suspending medium (50% suppression at approximately 0.5 mM divalent cation). Regulation of the PMI-1 epitope is independent of disassembly of the GPIIb-IIIa heterodimer, because it occurred at 22 degrees C and in response to mM magnesium as well as calcium. PMI-1 binding inversely correlated with fibrinogen binding. In addition, we identified a variant of Glanzmann's thrombasthenia with near-normal platelet content of the GPIIb-IIIa heterodimer as judged by crossed immunoelectrophoresis and surface labeling. Binding of PMI-1 to these patients' platelets was not dependent on reduction of the divalent cation concentration. These data suggest that the surface orientation of GPIIb is important in the capacity of platelets to bind fibrinogen.

[Venous emergencies. Personal experience and viewpoint]

Based on a casuistic report of 226 cases, the authors propose a classification of venous emergencies, including acute deep thrombo-phlebites (with their anatomo-clinical and topographical varieties), the complications of varicose disease, venous traumatism and anorectal venous thrombosis. The authors touch on problems associated with clinical and paraclinical diagnosis, prophylaxis and active surgical therapy, respectively thrombectomy, ligation of the long saphenofemoral junction, the treatment of varico-phlebitis and urgent traumatic lesions, the thrombectomy and radical cure of haemorrhoids. The coupling of any of these affections presents a potential of great seriousness, sometimes a major vital risk which necessitates immediate therapeutic intervention. The classification of the idea of "venous emergency" in comparison with that of "arterial emergency", is outlined, and the authors mention that a surgical treatment in these affections is to be preferred.

Cryopreservation of human bone marrow cells by a modification of the two-step cooling technique

The first attempt to freeze human bone marrow cells with a two-step cooling method is reported. A simple and reliable way of obtaining stable first-step subzero freezing baths is described. One-milliliter samples each containing 20 X 10(6) bone marrow cells and 10% Me2SO were frozen in polypropylene cryotubes. Using these experimental conditions, the optimal freezing temperature was found to be in the range of -36 to 37.5 degrees C for BM progenitor cell (GM-CFC, CFUE, and BFUE) survival. Such temperatures were easily obtained in stable sludges of anisole or K2CO3 eutectic solution in water. The optimal holding time was 20 min before plunging tubes into liquid nitrogen. Similar or improved progenitor cell recoveries were observed compared with the conventional cooling technique. Adaptation of this two-step technique for the freezing of large volumes of BM cells for autografting is under investigation.

Purification and cryopreservation of granulomonocytic colony forming cells (GM-CFC) from the blood of patients with chronic granulocytic leukemia (CGL) for autologous transplantation

A simple density-cut separation technique is described for obtaining GM-CFC concentrates from the peripheral blood of patients with chronic granulocytic leukemia (CGL) for autografting at the acute blastic phase of the disease. Large numbers of granulomonocytic colony forming cells (GM-CFC) were recovered from a single procedure (68.4 X 10(6) GM-CFC). The cryopreservation of these concentrates in liquid nitrogen allowed the recovery of 46.6 +/- 33.8% viable GM-CFC. An improved yield of GM-CFC was obtained by avoiding washing the cells (65.2 +/- 41.1%). The separation technique resulted in a concentrated suspension of progenitors in a small volume of medium (mean = 15 ml) allowing a great reduction in the amount of the cryoprotective agent injected into the patient at autografting. Preliminary data obtained in 4 patients transfused in blastic crisis after chemotherapy, with or without TBI, indicated the capacity of stored concentrates to repopulate these patients.

Diabetic lymphangiopathy. An optical and electron microscopic study

The lymphatic capillaries in the tegument of the dorsal side of the leg in patients with diabetes mellitus, and especially in those with clinically manifested macroangiopathy, present morphopathological modifications at the level of the endothelium and the basal membrane. Ultrastructurally, the modifications appear as dilatations of the intercellular space, dislocation or desquamation of the endothelium, an exaggerated growth of the micropinocytic vesicles, the appearance of the intracellular vacuoles and of the lysosomes. These modifications point to an increase in the endothelium permeability, which is an important phenomenon in the diabetic microangiopathy.

[Duodenogastric reflux after vagotomy and pyloroplasty (author's transl)]

In 27 patients after selective or truncal vagotomy and pyloroplasty the occurrence of duodenogastric reflux was checked by two methods, by the measurement of Bromsulphalein (BSP)-concentration in the gastric aspirate after BSP was given intravenously and by instillation of a barium meal in the second part of the duodenum followed by upper GI-series. In 20 of 23 patients reflux was recorded radiologically, in 18 of 27 patients reflux was shown by the BSP-Method. Proven bile reflux was associated with major postoperative discomfort, such as epigastric fullness, nausea and epigastric pain, it was also associated with gastritis as shown by microscopic examination of biopsies taken from the antrum. It is recommended to consider duodenogastric reflux as a possible reason for patients complaints after vagotomy and pyloroplasty. To avoid those complaints the preference of proximal gastric vagotomy without pyloroplasty is supported, if preoperative gastric emptying is not impaired.

[Occlusion of the renal artery by intra-arterial injection of thrombin in a case of inoperable renal tumour (author's transl)]

In a 53-year-old man with an inoperable metastasizing renal carcinoma embolic occlusion of the renal circulation was achieved by injection of thrombin (600 NIH units) through a balloon catheter into the renal artery. With short-term administration of analgesics and under anti-biotic cover the post-embolic course ran without complications. The general condition of the patient is good and macrohaematuria had, at the time of the report, not recurred for two months.

[The distribution of Sn2+ after application as a complex (author's transl)]

On animal experiments was shown that Sn2+ after i.v. application with 113Sn as radioactiv indicator was deposited in the skeleton. Experiments were done with citrat-, tartrat-, pyrophosphat-, phosphat- and Sn2+/HCl-complexes. The importance of the results for the use of Sn2+-solutions in Nuclear Medicine for men are discussed.