Biomedical subjects

Hisato Takatsu

Publications and source records attributed to Hisato Takatsu.

3 recordsLinked to original sources

PubMed2005

Assessment of arterial medial characteristics in human carotid arteries using integrated backscatter ultrasound and its histological implications.

Recently, ultrasound tissue characterization of the carotid arteries with an integrated backscatter (IB) analysis was shown to identify a high-risk group of atherosclerosis. To clarify whether IB ultrasound is useful in assessing arterial sclerosis as well as stiffness beta and whether IB values reflect the histological structure, we measured IB values of common carotid media in 52 subjects without coronary risk factors and in 10 patients with systemic sclerosis (SSc) in the clinical studies and 12 patients in the histological studies with a Philips Medical Systems Sonos 5500. IB values were correlated with age (r=0.69, P<0.0001), intima-media thickness (r=0.72, P<0.0001) and stiffness beta (r=0.80, P<0.0001) in the control subjects. IB values and stiffness beta in the SSc group were greater than in an age- and sex-matched control group (IB values: 9.6+/-2.7dB versus 16.1+/-1.8dB; stiffness beta: 11.5+/-4.5 versus 20.6+/-5.6, P<0.01). IB values of the media were correlated with the elastic fragmentation index (r=0.63, P=0.029) and the collagen fiber index (r=0.59, P=0.046). Measurements of IB values of carotid media are useful for non-invasively evaluating arterial sclerosis.

Adolescent↗

PubMed2003

Decrease of beta-cells and increase of alpha-cells in a diabetic patient with mitochondrial DNA 3243 (A-->G) mutation.

We report here a case of a 53-year-old woman with mitochondrial 3243 (A-->G) mutation diabetes. Diabetes mellitus was diagnosed at 39 years of age. At 50 years of age, cardiomyopathy and hypothyroidism were noted. At 53 years of age, the patient was admitted to our hospital for treatment of necrotic ulceration of toes. However, she died of massive heart failure. Pathological examination at autopsy showed a decrease in size, number, and acidophilicity of islets in the pancreas. Immunohistochemical stain revealed a decrease in the beta-cell population to 20.5+/-9.2% and a relative increase in alpha-cell population to 48.6+/-11.5%.

Cardiomyopathy, Dilated↗

PubMed2002

In vivo quantitative tissue characterization of human coronary arterial plaques by use of integrated backscatter intravascular ultrasound and comparison with angioscopic findings.

BACKGROUND: The purpose of the present study was to define whether integrated backscatter (IB) combined with conventional intravascular ultrasound (IVUS) makes tissue characterization of coronary arterial plaques possible. METHODS AND RESULTS: IB-IVUS was performed in coronary arteries (total 18 segments) of 9 patients at autopsy, and the findings were compared with the histology. RF signals, which were digitized at 2 GHz in 8-bit resolution, were obtained with an IVUS system with a 40-MHz catheter. IB values of the RF signal from the region of interest (ROI) (100-microm depth, 1.4 degrees per line) were calculated by use of a personal computer. IB values on the ROIs were divided into 5 categories, compared with each of the plaque histologies: category 1 (thrombus), -88 < IB < or = -80; category 2 (intimal hyperplasia or lipid core), -73 < IB < or = -63; category 3 (fibrous tissue), -63 < IB < or = -55; category 4 (mixed lesions), -55 < IB < or = -30; and category 5 (calcification), -30 < IB < or = -23. On the basis of these categories, we analyzed 5120 ROIs per segment in each ring-like arterial specimen. Color-coded maps of plaques were constructed by use of these IB data and conventional IVUS data, which reflected the plaque histology of autopsied coronary arteries well. Then, the same method was undertaken in 24 segments with plaque from 12 patients in vivo with angina pectoris. Comparisons between coronary angioscopy and IB-IVUS revealed that the surface color of plaques in angioscopy reflected the thickness of the fibrous cap rather than the size of the lipid core. CONCLUSIONS: IB-IVUS represents a new and useful tool for evaluating the tissue structure of human coronary arterial plaques.

Aged↗