[Surgical treatment for infective endocarditis with multiple embolic complications].

A 59-year-old man was transferred to our hospital because of severe right leg pain, dyspnea and anuria. Due to severe cyanosis of the legs below the knees and severe hyperkalemia, he had undergone embolectomy of the right femoral artery and hemodialysis. Medical treatment for infective endocarditis was started after the first operation, because transesophageal echo cardiography revealed severe aortic regurgitation and massive vegetation of the aortic valve. Amputation of the right leg below the knee and of the left leg below the Lisfranc joint was performed after 19 days and aortic valve replacement with patch closure of a perivalvular abscess was performed one month after the first operation. The post-operative course was uneventful. He was weaned from hemodialysis and the follow-up echocardiographic study revealed no vegetation.

Do structural changes of T cell receptor complex occur in tumor-bearing state?

T cells in tumor-bearing mice and cancer patients were recently shown to be devoid of CD3-zeta chain, a signal-transducing invariant chain in T cell receptor (TCR) complex, and p56lck tyrosine kinase. In the present study, we investigated the structure and function of TCR complex in T cells from BALB/c mice bearing CSA1M fibrosarcoma. The expressions of TCR chains and p56lck in a T cell-enriched population from spleen were analyzed. Almost complete loss of CD3-zeta and p56lck was observed in the preparation from tumor-bearing mice as assessed by immunoblotting analysis using whole cell lysates, whereas the amounts of other TCR chains were relatively unchanged. However, these changes were due to the increase of contaminating Mac-1+ cells in the spleen of tumor-bearing mice because: 1) the removal of Mac-1+ cells led to the restoration of CD3-zeta and p56lck; and 2) CD3-zeta was clearly present when the preparation was solubilized with ionic detergent. Fc receptor gamma chain detected in the preparation from tumor-bearing mice disappeared along with the removal of Mac-1+ cells. These observations were further supported by the finding that addition of Mac-1+ cells from tumor-bearing mice to normal T cells resulted in loss of CD3-zeta, leaving CD3-epsilon largely intact. When T cells from tumor-bearing mice were highly purified by depletion of Mac-1+ cells, these T cells contained normal amounts of CD3-zeta at mRNA, protein, and surface levels, and expressed the properly assembled TCR complex on their cell surface. Moreover, stimulation of the TCR in these T cells by anti-TCR antibodies resulted in a comparable Ca2+ mobilization to that observed in normal T cells. These results suggest that no structural changes occur in TCR complex in our tumor-bearing mice, and that complete depletion of Mac-1+ cells in important to assess the structure of TCR complex.

Transesophageal echocardiographically detected atherosclerotic aortic debris in a patient with systemic embolism following coronary angiography.

Transesophageal echocardiography (TEE) has enabled detection of the cardiac source of systemic emboli. We report the case of a patient who manifested systemic, multiple embolization in the kidney, skin, and upper gastrointestinal tract following coronary angiography. TEE allowed visualization of the atherosclerotic debris in the thoracic aorta. The clinical picture of the patient was consistent with that of cholesterol embolism. We recommend that patients with extensive atherosclerotic disease should undergo TEE before cardiac catheterization or other invasive procedures involving the aorta are carried out.