Demonstration of reperfusion after thrombolysis with technetium-99m isonitrile myocardial imaging

Technetium-99m isonitrile myocardial perfusion imaging was employed in a patient undergoing thrombolytic therapy with recombinant tissue plasminogen activator for acute anteroseptal myocardial infarction. Technetium-99m isonitrile does not demonstrate significant myocardial redistribution after intravenous injection. The imaging agent was administered in the emergency room, prior to the initiation of thrombolytic therapy. The initial area at risk for infarction was visualized on images obtained after the patient had been effectively treated. Imaging performed 5 days later, after repeat injection of [99mTc]isonitrile, showed a smaller myocardial perfusion defect indicating salvage of myocardium. Thus, this technique offers promise as a noninvasive means of assessing the area at risk, the success of reperfusion, and the presence of salvaged myocardium, early in the course of acute myocardial infarction.     

In-111-labeled leukocyte scintigraphy in suspected orthopedic prosthesis infection: comparison with other imaging modalities

When infection of prosthetic orthopedic implants is suspected, optimal management requires accurate confirmation or exclusion of infection. The authors retrospectively studied 98 patients with possible infection who underwent scanning with indium-111-labeled white blood cells (WBCs) and subsequently underwent surgery within 14 days. At surgery, 50 patients had infections, as determined by means of culture or histologic results. The diagnostic accuracy of In-111 scanning was compared with that of plain radiography, arthrography, three-phase bone scanning, and various clinical and laboratory findings classically associated with infection. Positive findings on In-111 WBC scans and elevated erythrocyte sedimentation rates were found to be the most predictive variables in the diagnosis of septic prostheses (P less than or equal to .001 and P less than or equal to .002, respectively). Likelihood ratio analysis more clearly demonstrated the superiority of In-111 WBC scanning, with positive and negative scans yielding likelihood ratios of 5.0 and 0.16, respectively.     

Alcohol use among migrant laborers in western New York

A survey of alcohol use among 217 Black and Haitian migrant agricultural workers was conducted in 13 camps in three counties of upstate New York. The orienting hypothesis stated that older, unattached men account for much of the drinking on migrant camps and that older, unattached men have experienced a variety of personal troubles as a result of their drinking. The results of the survey were found to support the initial hypothesis. In camps composed primarily of family groups, social control mechanisms were found to be more highly developed than in camps composed primarily of unattached, isolated men. It was also found that this difference in degree of social control was reflected in differences of drinking behavior. It is suggested that the mechanization of agriculture has become a self-reinforcing process that results in a proportional increase in the use of the homeless and troubled as a source of low-cost agricultural labor.     

Cardiovascular risk factors in young snuff-users and cigarette smokers

We studied cardiovascular risk factors in 21 young men who were habitual snuff-users, and compared them with the same risk factors in 18 non-tobacco-users and 19 cigarette smokers of the same age and body mass index. Both snuff-users and smokers showed increased levels of alcohol and coffee consumption and a decreased level of physical exercise compared to non-users. Both groups of tobacco-users showed increased serum insulin levels compared to the control group at similar blood glucose concentrations. In contrast to the smokers, snuff-users showed no significant elevation of diastolic blood pressure, haemoglobin concentrations, white cell count, serum cholesterol or triglyceride levels. Snuff users had higher plasma fibrinogen levels than non-users (P = 0.07). The use of snuff by young men appears to have less impact than smoking on cardiovascular risk factors, with the possible exception of elevated serum insulin and plasma fibrinogen levels.     

Shwachman syndrome: Exocrine pancreatic dysfunction and variable phenotypic expression

BACKGROUND & AIMS: Shwachman syndrome is an inherited condition with multisystemic abnormalities, including exocrine pancreatic dysfunction. The aim of this study was to evaluate the occurrence and progression of features in a large cohort of patients. METHODS: Clinical records of 25 patients with Shwachman syndrome were reviewed. RESULTS: Mean birth weight (2.92 +/- 0.51 kg) was at the 25th percentile. However, by 6 months of age, mean heights and weights were less than the 5th percentile. After 6 months of age, growth velocity was normal. Severe fat maldigestion due to pancreatic insufficiency was present in early life (fecal fat, 26% +/- 17% of fat intake; age, < 2 years). Serial assessment of exocrine pancreatic function showed persistent deficits of enzyme secretion, but 45% of patients showed moderate age-related improvements leading to pancreatic sufficiency. Neutropenia was the most common hematologic abnormality (88%), but leukopenia, thrombocytopenia, and anemia were also frequently encountered. Patients with hypoplasia of all three bone marrow cellular lines (n = 11) had the worst prognosis; 5 patients died, 2 of sepsis and 3 of acute myelogenous leukemia. Other findings included hepatomegaly and/or abnormal liver function test results and skeletal abnormalities. CONCLUSIONS: A wide and varied spectrum of phenotypic abnormalities among patients with Shwachman syndrome is described. Pancreatic acinar dysfunction is an invariable abnormality. Patients with severe bone marrow involvement may have a guarded prognosis. (Gastroenterology 1996 Dec;111(6):1593-602)     

CD28 co-stimulation stabilizes the expression of the CD40 ligand on T cells

The ligand for CD40 (CD40L) is a protein which is expressed on CD4 T cells following their activation: CD40-CD40L interactions are absolutely required for the induction of T cell-dependent antibody responses, yet little is known about the mechanisms whereby CD40L+ primary T cells activate naive B cells, since the protein is only transiently expressed and is rapidly down-regulated following T cell-B cell contact. We show here, using a variety of assays, that co- stimulation of primary murine T cells via CD3 and CD28 stabilizes the expression of the CD40L protein. Firstly, T cells stimulated in this manner express higher levels of CD40L when activated in the presence of B cells, compared to CD3-activated T cells. Secondly, the CD40L expressed on CD28-co-stimulated T cells is more resistant to B cell- induced down-regulation. Finally, CD3/CD28-preactivated, rested T cells re-express higher levels of CD40L more rapidly following re-stimulation via CD3 than T cells preactivated via CD3 alone. CD3/CD28-preactivated T cells, but not CD3-activated cells, are competent to induce DNA synthesis in naive B cells, and this requires re-stimulation via CD3 and prolonged ligation of CD40. These data therefore reinforce the concept that naive T cells need to be activated initially by cognate interaction with B7-bearing antigen-presenting cells (such as dendritic cells), before becoming competent helper effector cells capable of driving B cells into proliferation via a CD40-dependent pathway.