Magnetic deflection of neutral sodium-doped ammonia clusters.

We describe the setup and the performance of a new pulsed Stern-Gerlach deflector and present results for small sodium-doped ammonia clusters Na(NH3)n (n = 1-4) in a molecular beam. NaNH3 shows the expected deflection of a spin ½ system, while all lager clusters show much smaller deflections. Experimental deflection ratios are compared with the values calculated from molecular dynamics simulations. The comparison reveals that intracluster spin relaxation in NaNH3 takes place on a time scale significantly longer than 200 µs. Assuming that intracluster relaxation is the cause of the reduced deflection, relaxation times seem to be on the order of 200 µs for all larger clusters Na(NH3)n (n = 2-4). Our work is a first attempt to understand the magnetic properties of isolated, weakly-bound clusters with relevance to the variety of diamagnetic and paramagnetic species expected in solvated electron systems.

Incomplete revascularization in multivessel percutaneous transluminal coronary angioplasty: the role for stress thallium-201 imaging.

Evaluation of patients with multivessel coronary disease for percutaneous transluminal coronary angioplasty raises the question: Is incomplete revascularization an acceptable procedure in these patients, or does complete revascularization need to be performed, as in coronary artery bypass grafting? To provide an answer the present study utilized exercise thallium imaging as a guide to the performance of angioplasty in 85 patients with multivessel coronary disease. Preangioplasty exercise thallium imaging helped to identify the primary stenosis ("culprit lesion") in 93% of patients. Two weeks to 1 month after dilation of this lesion, repeat thallium imaging identified two patient groups: Group 1, 47 patients with no evidence of ischemia in a second vascular distribution and Group 2, 38 patients with evidence of further angioplasty. In Group 2 47% of patients had angioplasty of a second vessel and 79% required multivessel angioplasty at 1 year follow-up. In contrast, only six Group 1 patients (13%) required angioplasty of a second vessel at 1 year. Thus, incomplete revascularization may be an acceptable approach in many patients with multivessel coronary disease. Stress thallium-201 imaging may be a useful technique in the evaluation and management of these patients.

Pelger-Huet anomaly of granulocytes in a patient with tuberculosis.

The association of abnormal granulocyte nuclear formation and tuberculosis was first reported by Pelger in 1928. Huet, however, concluded this defect was hereditary, and the association of Pelger-Huet anomaly (PHA) of granulocytes and tuberculosis was obscured for many years. We report the second patient in the English literature with severe tuberculous infection and PHA, further substantiating the diagnostic and prognostic importance of PHA and tuberculosis.