Hirotsugu Tabata

Production of B cell stimulatory factor-2/interleukin-6 activity by human endothelial cells

The effect of culture supernatants of endothelial cell (EC) lines on the immunoglobulin-M(IgM) synthesis by human B cell line, SKW6-CL4 cells, was investigated. Supernatants of human EC stimulated IgM synthesis, as high as 6-fold, but supernatants of bovine EC did not. This enhancing activity was completely blocked by addition of anti-human B cell stimulatory factor-2/interleukin-6 (BSF-2/IL-6) antibody. These data suggest that human EC might participate in the human antibody production system by producing soluble factor, BSF-2/IL-6.

Angioscopic identification of coronary thrombus in patients with postinfarction angina

OBJECTIVES The purpose of this study was to determine the prevalence of intracoronary thrombus and associated anatomic abnormalities in patients with postinfarction angina using coronary angioscopy and angiography. BACKGROUND Postinfarction angina, previously studied by angiographic methods only, identifies patients at high risk for sudden death, recurrent angina and refractory angina. The recent development of coronary angioscopy, which permits direct observation of a thrombus or atheroma and is especially used for the detection of intraluminal changes, encourages a reexamination of the pathogenesis of postinfarction angina. METHODS Fifty-one consecutive patients with a diagnosis of acute myocardial infarction underwent cardiac catheterization. Coronary angiography followed immediately by coronary angioscopy was performed in 17 patients with and 34 without postinfarction angina during the same period of time (10.2 +/- 3.7 or 15.7 +/- 5.5 days [mean +/- SD]) after the onset of acute myocardial infarction. RESULTS The frequency of thrombus, as observed by angioscopy, was significantly higher in patients with than without postinfarction angina (17 of 17 vs. 5 of 34, respectively, p < 0.01). There were no significant differences between groups with respect to degree of stenosis in the infarct-related artery, number of vessels with significant stenosis, presence of collateral flow, type of therapy and risk factors. CONCLUSIONS Infarct-related artery thrombus is universally present in postinfarction angina and may be the primary pathogenic factor. Angioscopy is much more sensitive than coronary angiography for the detection of coronary thrombus.

Inhibitory effect of human recombinant interleukin-1 α and β on growth of human vascular endothelial cells

Abstract Endothelial cell growth factor(ECGF) is a potent polypeptyde mitogen which stimulates the growth of endothelial cells. The mitogenic effect of ECGF was inhibited by addition of recombinant interleukin-1 (rIL-1) α or β in a concentration dependent manner. The morphological change was not observed distinctly. In the condition without ECGF, both types of rIL-1 enhanced [3H] -thymidine uptake slightly, but failed to increase cell numbers. These data suggest the possibility that the effect of rIL-1 on EC is modulated by the presence of ECGF.

Expression of TLiSA1 on T cells from patients with rheumatoid arthritis and systemic lupus erythematosus

The expression of a new activation antigen, T cell lineage specific activation antigen (TLiSA1) on peripheral blood T cells from 16 rheumatoid arthritis (RA) and 8 systemic lupus erythematosus (SLE) patients and synovial fluid T cells from RA patients was determined in the context of T cell activation. The percentages of TLiSA1 positive T cells from inactive (4.6 +/- 5.2, mean +/- SE) or active RA (19.3 +/- 8.6) or inactive (1.7 +/- 2.1) or active SLE (8.7 +/- 2.7) were significantly increased compared with that of normal controls (0.7 +/- 0.4) (P less than 0.01). All patients with vasculitis showed relatively high positive percentages. The mean fluorocytometric intensity of TLiSA1 positive T cells from RA and SLE patients was significantly higher than that from normals. Percentages of TLiSA1 positive T cells from synovial fluids (21.8 +/- 4.9%) were significantly increased compared with those from peripheral blood of the same patients, indicating the local activation of T cells in patients with RA. An increase in the expression of TLiSA1 with no increase in the expression of the very late activating antigen 1 (VLA-1) was found in peripheral blood from RA, suggesting a difference in the stage of T cell activation in RA. In RA, there was a clinical correlation with levels of TLiSA1 expression on peripheral T cells. After stimulation with PHA, TLiSA1 positive percentages were increased on Day 2 and continued to increase through 5 days of culture. The maximum expression was obtained on Day 5. An increased number of TLiSA1 positive T cells belonged to OKT8. These results suggest that there is the systemic and the local activation of T cells in RA, following antigen stimulation, or a generalized nonspecific activation of immune system that could provide a means to monitor the abnormal immunologic activity in RA.

Stimulatory effect of CD5 antibody on B cells from patients with rheumatoid arthritis.

In order to clarify the role of CD5 antigen on B cell in autoimmunity, we examined B cells from patients with rheumatoid arthritis (RA). The percentages of CD5 positive B cells were increased in peripheral blood from RA compared with normal. Normal and RA B cells were stimulated with two kinds of monoclonal antibodies to CD5 (Leu-1, SL-1) which recognize different epitopes. RA B cells proliferated and secreted IgM by CD5 antibody stimulation in combination with IL-1. Our observations imply that CD5 positive B cells in RA are in their differentiation stage and that CD5 antigen might be one of the triggers to activate CD5 positive B cells in vivo to produce autoantibody.

Primary sarcoma of pulmonary artery resembling large pulmonary thrombus: diagnostic utility of different imaging modalities

A 70-year-old woman was hospitalized due to a 2-year history of dyspnoea and weight loss. A transthoracic echocardiogram showed a large ‘thrombus-like’ mass occupying the right ventricular outflow tract and the main pulmonary trunk ( Panel A ; see Supplementary material online, Movie S1 ). The Doppler study …

Primary Mural Endocarditis Without Valvular Involvement

Primary mural endocarditis is an extremely rare infection in which nonvalvular endocardial involvement is seen without any cardiac structural abnormalities such as ventricular septal defects. The rapid and precise diagnosis of this disease remains challenging. We present 2 cases (67‐ and 47‐year‐old male patients) of pathologically confirmed primary mural endocarditis that could have been detected by initial transthoracic echocardiography in the emergency department. Transthoracic echocardiography and transesophageal echocardiography play critical roles in the early recognition and confirmation of primary mural endocarditis.

Successful diagnosis of an atypical prosthetic vascular graft infection without perivascular abscess: luminal vegetation as the hidden septic source.

A 62-year-old woman with a vascular prosthesis for a common hepatic artery aneurysm (3 years ago) was hospitalized because of a 2-week history of lumbago and fever. Six months previously, she was hospitalized at another medical facility for 1 month because of a fever of unknown pathogenesis. Laboratory examination revealed moderate inflammation with an elevated C-reactive protein level of 6.5 mg/dL and a white blood cell count of 7070/mm3. Initial 8-row multi-detector computed tomography (CT) with contrast agent in the emergency department did not show any focus for the origin of the fever. She was referred to the orthopedic surgery department, and MRI of the pelvis revealed inflammation of the left sacroiliac joint (Figure 1). Her first 2 sets of blood cultures were positive for Streptococcus anginosus . Intravenous administration of ampicillin/cloxacillin sodium was started. She was then transferred to the cardiology department for the evaluation of septicemia, which could have been caused by infectious endocarditis. A transthoracic echocardiogram showed severe aortic regurgitation, which was not seen at the time of previous surgery for the vascular prosthesis (Figure 2A). However, a transesophageal echocardiogram only detected a small degenerative change in the right coronary cusp of the aortic valve, which could be healed …

Synchronicity of echocardiography and cardiac nuclear medicine in mid-ventricular ballooning syndrome: paired ‘ring signs’ on polar maps

A 74-year-old woman was hospitalized for chest pain. A coronary angiogram showed no organic stenosis in the coronary arteries. However, a left ventriculogram showed akinesis in the middle portion of the left ventricle (Supplementary data online, Movie S1 ). A transthoracic echocardiography (TTE) was performed, and two-dimensional longitudinal strain images obtained on the apical four-chamber view, …

‘Honeycomb appearance’ on three-dimensional transthoracic echocardiography as the landmark of left ventricular non-compaction: two case reports

IntroductionLeft ventricular non-compaction is a rare congenital heart disease, and is most commonly diagnosed via two-dimensional echocardiography according to echocardiographic criteria. Recently, transthoracic three-dimensional echocardiography has become available in the clinical setting.Case presentationWe present two isolated cases of left ventricular non-compaction from Japan (in an 84-year-old woman and 47-year-old man) that were confirmed by two-dimensional echocardiography, contrast-enhanced two-dimensional echocardiography, three-dimensional echocardiography and cardiac magnetic resonance imaging. In both cases, three-dimensional echocardiography successfully demonstrated the trabecular meshwork of the left ventricle, referred to as a ‘honeycomb appearance’.ConclusionsThree-dimensional echocardiography has the advantage of visualizing an en-face view of the trabecular meshwork, which is not possible with two-dimensional echocardiography. We further emphasize the clinical utility of three-dimensional echocardiography, which is not limited to just the observation of the trabeculations and inter-trabecular recesses, but can also visualize the trabecular meshwork with a ‘honeycomb appearance’.