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Biomedical subjects

T Shimamoto

Publications and source records attributed to T Shimamoto.

353 records · Page 20Linked to original sources
PubMedDate not supplied

Recent developments in the organic synthesis of lipid A in relation to biologic activities.

For elucidation of a relationship between chemical structure and biologic activity of lipid A, syntheses of 13 derivatives of glucosamine beta (1-6) disaccharide, which were acylated at 3, 4, and 6'-hydroxyl groups and/or phosphorylated at positions 1 and 4', were carried out. The results showed the importance of the presence of the phosphate group at either position 1 or 4' and of the beta-hydroxyl group in acyl function, particularly in N-linked fatty acids, for the exhibition of biologic activities characteristic of lipid A. New evidence on the positions of fatty acids in natural lipid A of Escherichia coli species obtained by means of 2D-H nuclear magnetic resonance was also demonstrated; the findings indicate that the 3'-hydroxyl group is acylated and the 6'-hydroxyl group in the molecule must be free.

Lipid A↗
PubMedDate not supplied

Small cell carcinoma of the bladder. Two cases diagnosed by urinary cytology.

BACKGROUND: Primary small cell carcinoma (SCC) of the bladder is a rare but important entity. We report two cases of SCC of the bladder diagnosed by urinary cytology. CASES: A 71-year-old male (case 1) and a 79-year-old female (case 2) presented with asymptomatic gross hematuria. Urinary cytology in case 1 showed the presence of a few undifferentiated malignant small cells and many transitional cell carcinoma (TCC) cells with a bloody and necrotic background. The former cells were small and round, with naked, hyperchromatic nuclei and finely granular chromatin. Pathologic diagnosis after total cystectomy was TCC > SCC > adenocarcinoma, T2M0N0. Urinary cytology of case 2 showed the presence of many undifferentiated malignant small cells and many TCC cells with or without squamous metaplasia. Cytologic features of the former cells were almost the same as those in case 1. Moreover, these cells were neuroendocrine marker positive by immunocytochemistry. Pathologic diagnosis after tumor resection was SCC and TCC > squamous cell carcinoma, T1b. CONCLUSION: The prognosis of primary SCC of the bladder is usually poor. Because our cases were found by urinary cytology at a relatively early stage, both have been well, without any evidence of recurrence, 30 and 25 months after surgery even without adjuvant therapy.

Aged↗
PubMedDate not supplied

Secular trends in atherosclerosis of coronary arteries and basal cerebral arteries in Japan. The Akita pathology study.

The atherosclerotic lesions of the coronary arteries and basal cerebral arteries in the circle of Willis were examined in the bodies of decreased men ages 30 and over who had been admitted to a local hospital in northeast Japan during 1966 to 1974 (243 men) and 1975 to 1984 (602 men). The autopsy rates during the two periods were 86% and 89%, respectively. The extent of atherosclerosis was determined blindly by one pathologist using a grading method of cross-sectional stenosis scoring for coronary arteries and Baker's method for basal cerebral arteries. The age-adjusted mean scores for atherosclerosis in the coronary arteries and basal cerebral arteries were 30% and 42% lower, respectively, in the 1975 to 1984 period than in the 1966 to 1974 period (p less than 0.001). There was also a fall in age-adjusted blood pressure levels at admission: 10 mm Hg for systolic and 4 mm Hg for diastolic blood pressure (p less than 0.001). The opposite trend was seen in mean serum cholesterol: a rise from 171 mg/dl to 177 mg/dl (p = 0.018). Linear regression analysis indicated that blood pressure was positively associated with both atherosclerosis scores, controlling for age and serum cholesterol in both time periods (p less than 0.001). The association of serum cholesterol with the atherosclerosis scores was positive in both periods and statistically significant in 1975 to 1984. Similar findings were obtained when the analyses were conducted for cardiovascular disease (myocardial infarction and stroke) and for noncardiovascular disease, separately.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

A collaborative study of stroke incidence in Japan: 1975-1979.

A Japan Collaborative Study of Stroke covering 20 regional and occupational population groups was conducted with the support of the Ministry of Health and Welfare. In this study 17,423 males and 16,856 females, aged 40 to 69, were followed up prospectively from 1975 to 1979. The average annual incidence of all types of stroke was 3.94 for men and 2.52 for women per 1,000 population. The incidence of cerebral hemorrhage for men and women stood at 1.26 and 0.59 and that of cerebral infarction at 1.87 and 1.10 respectively. The difference in incidence between the sexes was large particularly in the age range of 40-49. The incidence of all types of stroke, cerebral hemorrhage and cerebral infarction increased with age. The incidence of all strokes in Japan during the period 1975-1979 appears to have decreased in comparison with that in 1960-1969, but tended to be still higher than that in Western countries.

Adult↗
PubMedDate not supplied

Comparative report on endoscopic and surgical treatment for early gastric cancer in elderly patients.

Two cases of elderly patients with similar early gastric cancers who were submitted to endoscopic and surgical treatment are presented as examples. Considering older patients as a sole group in the decision-making process we discuss the pros and cons of each therapy supporting efficacy and opposing side effects in order to maintain a reasonable quality of life.

Adenocarcinoma↗
PubMedDate not supplied

The role of rat copulatory plug for fertilization.

To investigate the contribution of the rat copulatory plug (RCP) to fertilization we evaluated the following: 1) its role as a reservoir for spermatozoa, 2) its role in the prevention of the outflow of spermatozoa from the vagina, and 3) its importance in the process of the sperm into the uterus. Artificial inseminations with either fresh RCP or epididymal spermatozoal solutions or the postcoital removal of the RCP was performed in normal female rats in estrus and in pseudopregnant rats (following relaxation of the cervix by faradic stimulation). The pregnancy rates in the different groups indicated that only the third mechanism was important.

Animals↗