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Biomedical subjects

T Kan

Publications and source records attributed to T Kan.

At least 37 records · Page 2Linked to original sources
PubMed1992

Antibacterial effect of bovine milk antibody against Escherichia coli in a mouse indigenous infection model.

A skim-milk fraction and a whey-protein concentrate (WPC) fraction were prepared from the cows that had been immunized with E. coli isolated from the mouse intestine. The antibacterial effect of these fractions against E. coli was examined. They contained antibody with a high affinity for E. coli strain 48, a representative strain in the mouse intestine, which is composed of a large amount of IgG and smaller amounts of IgA and IgM. Although these fractions showed no bactericidal or bacteriostatic activity against E. coli 48 directly in vitro, they exhibited strong agglutination and opsonization activities against the bacteria in vitro. The bacteria opsonized with the WPC fraction were taken up more effectively by liver macrophages in vivo, compared with unopsonized E. coli, after an intravenous injection into mice. Oral administration of the skim-milk fraction to mice significantly reduced the susceptibility to the lethal toxicity of 5-fluorouracil (5 FU). The increase in the population levels of E. coli in the intestinal tract after administration of 5 FU was inhibited by oral administration of the skim-milk fraction. These results strongly suggest that specific antibody may be effective in the prophylaxis against the indigenous infection with gram-negative bacteria such as E. coli after a period of chemotherapy in cancer patients.

Animals↗
PubMed1992

A noninvasive method of measuring Max(dP/dt) of the left ventricle by Doppler echocardiography.

Although slightly affected by alterations in preload, the maximum first derivative of left ventricular pressure with respect to time, Max(dP/dt), is widely regarded as a simple and convenient index of cardiac contractility for clinical use. The feasibility of noninvasive, hence repeatable, measurement of Max(dP/dt) will certainly lead to re-evaluation of its usefulness. Max(dP/dt) is given by the following equation: Max(dP/dt) = rho c Max(du/dt), where rho is the blood density, c the pulse wave velocity, and mu the flow velocity in the aorta. This equation has been previously validated in animal experiments and has now been applied to the clinical setting for the first time. In 20 patients without aortic stenosis, left ventricular pressure was measured with a catheter-tip micromanometer, aortic ejection flow velocity was measured by Doppler echocardiography, and pulse wave velocity by mechanocardiography or Doppler echocardiography. Then, delta c Max (du/dt was calculated from the measured data and compared with measured Max (dP/dt). A significant positive correlation was found between them (rho c Max (du/dt) = 0.96 x Max (dP/dt) + 6.52, r = 0.83, p < 0.001). In 11 patients with hypertension, rho c Max (du/dt) was obtained before and after long-term (average 13.1 months) treatment with antihypertensive drugs. In spite of the expected reduction in blood pressure and the regression of left ventricular mass, rho c Max (du/dt) remaioned unchanged. In 9 patients with dilated cardiomyopathy, the effects of beta 1-agonist were tested at the beginning of therapy (30 mg/day denopamine) and 6 months later. The increase in rho c Max (du/dt) observed 1 hour after oral administration of he drug had not changed significantly 6 months later. We conclude that the index rho c Max (du/dt), is useful in assessing the contractile state of the left ventricle noninvasively.

Antihypertensive Agents↗
PubMed1992

[An experimental pathologic study of acute small intestinal ischaemic in mongrel dogs--occluded proximal site of anterior mesenteric artery by balloon catheter].

We prepared experimental of small intestinal ischemia by occluding the inlet of the anterior mesenteric artery of adult mongrel dogs with balloon catheters. With these experimental models, the degree of tissue damage of the small intestinal mucosa, which became ischemic, was studied according to the different occlusion times of the anterior mesenteric artery (3, 5, 7, 10, 15 and 30 hours). As a result, ischemic mucosal lesions in the small intestine at an initial stage occurred on the antimesenteric side. In the gross findings of the mucosa when the occlusion time was within 5 hours, linear and spotted lesions appeared in a zone on the antimesenteric side. When the occlusion time was 7 hours or more, these lesions fused and the entire intestinal mucosa became a hemorrhagic lesion. By occluding the anterior mesenteric artery for 22-30 hours, all 6 experimental ischemic animals died.

Acute Disease↗
PubMed1992

[Pathological studies on microvasculature of arteriovenous malformation in the intestinal tract].

Intestinal arterio-venous malformation (AVM) is one of the uncommon causes of gastrointestinal hemorrhage and is usually difficult to diagnose before pathological study. Five operated cases with the AVM were presented. The vascular lesions were studied by barium-gelatin injection and routine histological procedures. The AVM lesion was detected in the proximal jejunum and in the distal ileum in each one case, respectively. In two other cases the AVM lesion was observed as a protruded tortuous vascular plexus in colonic mucosa. By the microangiographical study, it was confirmed that the main lesion of AVM was located in submucosal layer with complicating minute AVM in lamina propria of intestinal mucosa. In the mucosal lesion of AVM it was disclosed that arterialization of precapillary arterioles was a remarkable finding. Thickened intimal layer and duplication of internal elastic lamina were recognized in these arteriolar lesions. Two kinds of intestinal AVM were classified, one is located in the submucosal layer and another one is located in mucosal layer. It was suggested that a marked ectasia of mucosal vessels seemed to be a secondary change of the submucosal AVM. The pathogenesis of the mucosal AVM was discussed.

Adult↗
PubMed1990

[Noninvasive estimation of max (dP/dt) of the left ventricle based on maximum aortic flow acceleration as measured by pulsed Doppler echocardiography].

To obtain an index of left ventricular contractility, cardiac catheterization is necessary. In the present study, we ascertained whether max(dP/dt) could be obtained noninvasively in vivo based on the theoretical equation, max(dP/dt) not equal to rho cmax(du/dt), where rho is the density of blood, c is the pulse wave velocity of the aorta and max(du/dt) is the maximum acceleration of the aortic blood flow. This equation is based on the theory of pulse wave propagation, and was established in animal experiments. We further attempted to clarify the clinical usefulness of rho cmax(du/dt) by examining the effects of afterload and preload on rho cmax(du/dt). Twenty-seven patients without stenosis of their aortic valves and left ventricular outflow tracts were observed. During cardiac catheterization, we measured max(dP/dt) using a catheter-tip micromanometer, max (du/dt) using pulsed Doppler echocardiography and pulse wave velocity by simultaneously recording the femoral pulse wave and the carotid pulse wave. The measurements were performed at rest, before and after an increase in contractility with dobutamine administration, an increase in afterload with methoxamine administration and an increase in preload by leg elevation. There was good linear correlation (Y = 0.95X + 7.51, r = 0.84, p less than 0.0005) between max(dP/dt)[X] and rho cmax(du/dt)[Y] at rest. When the contractility was changed, rho cmax(du/dt) reflected changing of max(dP/dt). Moreover, when the afterload and preload were increased, the changing pattern of rho cmax(du/dt) was similar to that of max(dP/dt). Max(du/dt), index of cardiac performance previously proposed, showed a different changing pattern than max(dP/dt), indicating that max(du/dt) was influenced substantially by loading conditions. These results indicated that we can obtain max(dP/dt) noninvasively and reliably by measuring rho cmax(du/dt).

Aged↗
PubMed1989

[Radiological findings of cancerous invasion in colorectal cancer less than 3 cm in diameter].

131 colorectal cancers, less than 3 cm in diameter, experienced at Juntendo University Hospital in Oct. 1977 through Dec. 1988 were studied with respect to their radiological and macroscopic features. Macroscopic features of the cancers were classified into type a (a lesion with a long stalk), type b (a subpedunculated or sessile lesion), type c (a plaque-like lesion) and type d (a lesion with a depression). Type a is early cancer. An early cancer of type b was mostly demonstrated as a lobular pattern of tumor surface, and an advanced cancer as a nodular pattern. Type c less than 1 cm in diameter was seen a sm cancer. A sm cancer of type d was mostly demonstrated as a faint barium fleck of the depression, an advanced cancer as a mild barium fleck. By deformed colonic wall in profile view, an early cancer was mostly demonstrated as a thorn shape deformity, sm or pm cancer as an arch shaped deformity and a cancer with deeper cancerous invasion than pm as a trapezoid deformity.

Colorectal Neoplasms↗
PubMed1989

[Clinical pathological studies on colo-rectal cancer with a diameter of 1.5 cm or less].

This study was undertaken to investigate the average rate of carcinomatous occupation in 99 colorectal cancers with a diameter of 1.5 cm or less of each macroscopic form ("pedunculated", "tumor", plaque-like" and "central depression" type). The results were follows; The ratio carcinomatous occupation was low in "pedunculated" type in which "m" cancer was high in frequency . This ratio was high in "tumor" type a diameter of 1.0 cm or more in which "sm" cancer was high in frequency, showing that "tumor" type tend to invade from mucosal to submucosal layer. This ratio were high in "plaque-like" and "central depression" type in which "sm" and "pm" cancer were high in frequency, indicating that "plaque-like" and "central depression" type had little relation to adenoma.

Adenoma↗
PubMed1988

[An autopsy case of gastric metastasis simulating linitis plastica carcinoma from primary linitis plastica carcinoma of the rectum].

Cases of a metastatic involvement of the stomach from a colorectal cancer are extremely rare, and once such case, confirmed by autopsy, is reported. The patient, an 86-year-old woman, had a metastatic lesion of the stomach from a rectal cancer. The rectal cancer was a combined linitis plastica type and signet ring cell carcinoma, and the appearance of metastatic lesion of the stomach had simulated the linitis plastica type cancer. A metastatic involvement of the stomach presenting a linitis plastica type cancer from a breast cancer is well documented, but a linitis plastica type from a colorectal cancer has not been reported. This case is the first report concerning a gastric metastasis presenting linitis plastica type lesion from a colorectal cancer.

Adenocarcinoma, Scirrhous↗
PubMed1981

Effect of lactobacilli on urinary indican excretion in gnotobiotic rats and in man.

The effect of Lactobacillus species on urinary indican excretion in two types of gnotobiotic rats (GBH-9 and GB-5) and in man was studied. L. salivarius, L. plantarum and L. casei colonized in the cecum and colon of both types of rats at levels of 10(7) to 10(8) per gram of contents following one-dose oral administration and caused a significant reduction in urinary indican excretion, whereas two strains of L. acidophilus which colonized at low levels (10(4) to 10(5)/g) did not reduce indican excretion. Daily feeding of Lactobacillus concentrates caused a further significant reduction in indican excretion which was corrected by tryptophan intake, even in the case of L. acidophilus. There was a clear relationship between fecal lactobacillus counts and urinary indican. A significant reduction of indican secretion was obtained only when the fecal counts of lactobacilli exceeded 10(7).4/g in rats. L. casei also had an effect in man, reducing urinary excretion of indican and p-cresol. Reduction in indican excretion seems to be accompanied by decreasing fecal tryptophanase activity in rats and man. A negative correlation was also obtained between fecal resident lactobacilli and urinary indican in man (r = -0.532, n = 28, p less than 0.01). Subjects with lactobacilli at a level of 10(6)/g or more excreted less indican than those harboring the bacteria at levels below 10(5)/g.

Adult↗