Cognate antigen directs CD8+ T cell migration to vascularized transplants

The migration of effector or memory T cells to the graft is a critical event in the rejection of transplanted organs. The prevailing view is that the key steps involved in T cell migration - integrin-mediated firm adhesion followed by transendothelial migration - are dependent on the activation of Gαi-coupled chemokine receptors on T cells. In contrast to this view, we demonstrated in vivo that cognate antigen was necessary for the firm adhesion and transendothelial migration of CD8+ effector T cells specific to graft antigens and that both steps occurred independent of Gαi signaling. Presentation of cognate antigen by either graft endothelial cells or bone marrow-derived APCs that extend into the capillary lumen was sufficient for T cell migration. The adhesion and transmigration of antigen-nonspecific (bystander) effector T cells, on the other hand, remained dependent on Gαi, but required the presence of antigen-specific effector T cells. These findings underscore the primary role of cognate antigen presented by either endothelial cells or bone marrow-derived APCs in the migration of T cells across endothelial barriers and have important implications for the prevention and treatment of graft rejection.

The effect of sunlight on postoperative analgesic medication use: a prospective study of patients undergoing spinal surgery

OBJECTIVE

Exposure to natural sunlight has been associated with improvement in mood, reduced mortality among patients with cancer, and reduced length of hospitalization for patients who have experienced myocardial infarction. Our aim was to evaluate whether the amount of sunlight in a hospital room modifies a patient's psychosocial health, the quantity of analgesic medication used, and the pain medication cost.

METHODS

A prospective study of pain medication use was conducted in 89 patients undergoing elective cervical and lumbar spinal surgery where they were housed on either the "bright" or "dim" side of the same hospital unit. Analgesic medication was converted to standard morphine equivalents for interpatient comparison. The intensity of sunlight in each hospital room was measured daily and psychologic questionnaires were administered on the day after surgery and at discharge.

RESULTS

Patients staying on the bright side of the hospital unit were exposed to 46% higher-intensity sunlight on average (p = .005). Patients exposed to an increased intensity of sunlight experienced less perceived stress (p = .035), marginally less pain (p = .058), took 22% less analgesic medication per hour (p = .047), and had 21% less pain medication costs (p = .047). Age quartile was the only other variable found to be a predictor of analgesic use, with a significant negative correlation (p <.001). However, patients housed on the bright side of the hospital consistently used less analgesic medications in all age quartiles.

CONCLUSION

The exposure postoperatively of patients who have undergone spinal surgery to increased amounts of natural sunlight during their hospital recovery period may result in decreased stress, pain, analgesic medication use, and pain medication costs.

[One-year follow-up of a population of patients with angina. Factors influencing mortality and occurrence of cardiovascular events. Results of the ELAN study]

The ELAN (Etude longitudinale dans l'angor) study was carried out both to acquire better knowledge of the occurrence of major cardiovascular events (myocardial infarction, revascularization surgery, death) in patients followed up for angina pectoris, and to determine the factors influencing such events. A cohort of angina patients was formed in January 1997, and 3,284 patients were followed up by 488 French cardiologists during a one-year period. Of these 3,284 patients, 96 (29/1000) died; causes of death included underlying coronary heart disease in 31, sudden death in 8, other cardiac aetiologies in 35, and noncardiac causes in 22. Sixty-nine (21/1000) patients developed myocardial infarction, 240 (73/1000) underwent PTCA, and 119 (36/1000) underwent coronary bypass surgery. Factors associated with an increased risk of death were age, diabetes mellitus, heart failure and angina type, mixed and rest angina being associated with poorer prognosis compared to exertional angina. Infarction risk increased with age and a history of previous infarction. Analysis of therapeutic factors after adjustment for the above risk factors showed a beneficial effect of betablockers on both cardiovascular and all-cause mortality and of aspirin on all-cause mortality.

[Characteristics of a cohort of 4,000 French patients with angina. The ELAN study]

The ELAN (Etude Longitudinale dans l'ANgor) study was carried out to evaluate factors influencing the occurrence of death, myocardial infarction and revascularization procedures in patients with known angina pectoris. Analysis of baseline data collected in January 1997 involves 4,035 patients throughout France, which were recruited by 613 cardiologists practising on a private, hospital or mixed basis. The study population comprised 75% of men with a mean age of 65 years and 25% of women with a mean age of 70 years. Eighty eight percent of the patients had at least one cardiovascular risk factor, and nearly half of them had two or more factors; hypercholesterolemia and hypertension were the two most frequent ones. Reported cardiovascular past events included myocardial infarction in 47% of patients, PTCA in 33% and aorto-coronary bypass in 24%. Angina pectoris had been diagnosed within the previous year in 39% of patients. Exertional angina was the most common type (66%), with grade I/II angina being most frequently found (more than 70% of all cases). Management strategies are especially described for angina patients diagnosed within the previous year. More than half of the patients had undergone exercise testing within the previous 12 months, while scanning and coronary arteriography had been performed in 15% and 72%, respectively. Ninety five percent of patients were under antianginal drug therapy, with combined therapies being used in 58% of them. The most frequently prescribed drugs were betablockers (63%) and nitrates (53%). In 74% of patients, aspirin was given in addition to conventional antianginal agents. These data will be reviewed in a one-year cohort analysis as potential predictive factors for the occurrence of cardiovascular events.