In the last few years, the CT scanner has been greatly improved in terms of the output of X-ray units, storage capacity and processing speed. A spiral volumetric CT scanner with slip-ring system has made it easier to reform three-dimensional (3D) images. Literature concerning the usefulness of 3D CT imaging itself in a clinical application is scarce. 3D-CT angiography by intravenous injection of contrast media must play an important role in the clinical use of the 3D CT. However, with regard to vascular disorders such as an aortic dissection, the problem of the possible visualization of a false lumen without blood flow can not as yet be considered to be settled. Even in 3D-CT angiography the problem of observing the inner space of a vessel remains unsolved, and it remains as a dead space. We have developed a new CT-endoscopy (CTES) technique ('92), which is an attempt to solve an unsolved problem, in collaboration with HITACHI Medical Corp., Japan. In this article the author explains the general concept of spiral volumetric CT, and fully describes some initial clinical experiences with the CTES method.

View full abstract

We have reported that the liver is closely associated with the hematolymphoid system and that the liver, as a lymphoid organ, may play an important role in the differentiation of lymphocytes and oral tolerance. To investigate the relevance of the liver to immunological tolerance, we compared the response pattern to Staphylococcus enterotoxin B (SEB) in intrahepatic lymphocytes (IHL) with those of spleen cells (SPC) and mesenteric lymph node cells (mLNC) during tolerance induction.
Tolerance was induced by i. v. injections of SEB in all three organs. IHL had a distinct pattern from the other cells in the induction of unresponsiveness to SEB. While SPC and mLNC have a proliferation phase before the reduction of DNA synthesis, IHL become tolerant immediately without this phase. When IHL became tolerant in the early period after SEB injection, their nylon-wool column non-adherent (NW-NA) IHL were not recovered from unresponsiveness in vitro in spite of the addition of irradiated normal SPC as accessory cells. NW-NA IHL did not secrete IL-2 during this process, indicating that NW-NA IHL were in a state of functional anergy soon after the i. v. administration of SEB. Phenotypic analysis revealed that the characteristic changes of IHL during the induction of unrespon-siveness might be associated with the kinetic modulation of CD 4⁺ Vβ 8⁺ T cells. These results suggest that the liver may hold a different mechanism for the induction of tolerance to SEB from that of SPC and mLNC.

View full abstract

Non-invasive recording of the late potential (LP) by signal-averaging technique is useful in predicting ventricular tachycardia (VT), especially in patients with myocardial infarction (MI). However, the rate of positive LP is LOW in anterior or anteroseptal MI, since the LP is masked by QRS complex. The purpose of the present study is first, to detect local conduction delay in initial portion of QRS complex and secondly, to evaluate the clinical significance of the initial delay in patients with MI. Eighty patients with MI were analyzed; AS: anteroseptal, n=18, including 6 VT, A: anterior, n=22, 7 VT, I: inferior, n=28, 9 VT, and P: posterior, n= 12, noVT. Twenty non-MI patients were used as normal controls (N). A signal processor (NEC 7 T 18) was used to record signal-averaged electrocardiograms and each 10 msec integral value of filtered QRS complex from the initial upstroke to the 60 msec point was automatically measured.
The integral values of groups AS and A were lower than those of groups I, P, and N. AS with VT showed a lower integral value than AS without VT, but no differences were observed between A with VT and A without VT.
We conclude that there is a much lower upstroke of signal-averaged initial QRS complex in patients with anteroseptal MI with VT, suggesting that the local conduction delay at the ventricular septum plays an important role in the mechanism of VT in these patients.

View full abstract

Because of the continued controversies about the nature of atypical endogenous psychoses and their relationship to typical endogenous psychoses such as schizophrenias or affective disorders, a visual evoked potential (VEP) study was performed on 11 patients with atypical endogenous psychosis, 6 schizophrenics (both medicated) and 11 normal controls to observe the characteristics of cerebral responsiveness in atypical endogenous psychoses.
VEPs were elicited by flashes. A modification of Kadobayashi's addition task method was employed as the mental task and the changes in P 100 amplitude of the VEPs at the time points of 1, 3, 5, 7, 9 and 11 minutes after the task were estimated from the amplitude ratios before and after the task.
A majority of the patients with atypical endogenous psychosis (73%) showed remarkable increases in VEP amplitude after the mental task, and the rest showed decreases regardless of the variety in their clinical features such as confusion, elation or depression, being in part consistent with the findings in bipolar affective disorders previously reported by this author and his colleagues. On the other hand, the schizophrenics all showed remarkable decreases in VEP amplititude after the task with a mean value of amplitude ratios of 65.1 ± 14.7.
In group comparisons between both disorders of the amplitude ratio at each time point within 11 minutes after the task and in their average, the differences reached a statistically significant level at all time points except 11 minutes after the task and in their average.
In the normal controls the amplitude changes were slight with a mean value of amplitude ratios of 95.1 ± 9.9. Between the normal controls and the schizophrenics, significant differences were found at all time points except 5 and 11 minutes after the task and in their average.
Patients with atypical endogenous psychosis showed higher incidences of the amplitude ratios deviating from the normal range than the normal controls. The differences were of statistical significance at all time points except 3 and 11 minutes after the task and except in their average.
From the viewpoint of the neurophysiological aspect of cerebral evoked potentials the author discussed the similarities of brain excitability in atypical endogenous psychoses and affective disorders.

View full abstract

To define the lower limit at which old age sets in the author examined life factors of such as religion, school career, family structure, working conditions, health conditions, income and life satisfaction as well as the quality of well-being (activity in daily life and health impairment in the modified Kaplan's Well-being scale) during the month of May 1995. A total of 273 subjects were randomly sampled from the inhabitants aged 50 years and over, in Shirahama-machi, Chiba Prefecture in uniform number of gender and cohort, and then cohort differences in the life factors and the quality of well-being and health impairment were statistically analyzed.
The cohort differences were found in the majority of items examined below and over 80 years in males and below and over 70 years in females. This result indicated that the lower limit of old age is 80 years in males and 70 years in females.

View full abstract