High levels of the shed form of L-selectin are present in patients with acute leukemia and inhibit blast cell adhesion to activated endothelium.

L-selectin is expressed by most leukocytes and mediates the initial step of adhesion to vascular endothelium. A feature of this adhesion receptor is to be shed from the cell surface. We report here the presence of high levels of the shed form of L-selectin (sL-selectin) in plasma from patients with acute leukemia.

[Prekallikrein deficiency: apropos of 2 cases].

An isolated, considerably prolonged aPTT (117 and 112 sec respectively; normal range 26-36 sec) was discovered during the preoperative workup in 2 patients aged 48 and 66 years. Both had a negative personal and family history for bleeding. Levels of the intrinsic coagulation factors which potentially cause a bleeding risk (VIII, IX, XI) were normal, and an inhibitor of the aPTT could not be detected.

[Visceral leishmaniasis (kala-azar) and HIV infection. Apropos of a case and literature review].

A 42 year old male Spanish patient who presented since one year a symptomatic stage IV C1,C2,D HIV infection (Pneumocystis carinii pneumonia, cerebral toxoplasmosis, esophageal candidiasis, Kaposi's sarcoma) became progressively asthenic with weight loss, diarrhea, fever and complained about bone pain. These symptoms could be attributed to visceral leishmaniasis. This novel opportunistic infection should be considered in the differential diagnosis of fever of unknown origin in HIV+ patients coming from or having travelled in endemic areas.

Phase I study of Brequinar sodium (NSC 368390) in patients with solid malignancies.

Brequinar sodium (DUP 785, NSC 368390) is a novel quinoline-carboxylic acid derivative that has been selected for clinical evaluation because of its broad spectrum of antitumor activity in animal models and its novel chemical structure. This compound inhibits the mitochondrial enzyme dihydroorotate dehydrogenase (DHO-DH), which catalyzes the conversion of dihydroorotate to orotate, leading to a blockage in the pyrimidine de novo biosynthesis. A total of 43 patients received 110 courses of Brequinar sodium by short-term intravenous (i.