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Biomedical subjects

S Takebayashi

Publications and source records attributed to S Takebayashi.

At least 217 records · Page 12Linked to original sources
PubMed1979

Mast cells in human aorta.

Aortic specimens from 111 autopsy and 23 surgical cases were examined by light and electron microscopy. Differential mast cell counts were made of three aortic segments (ascending, thoracic, and abdominal) and layers (intimal, medial, adventitial). The mast cell counts varied considerably from case to case and sector to sector and generally showed no correlation with age, sex, or atherosclerotic severity. However, intimal mast cells were fewer in number in areas of lipid accumulation than in areas of diffuse intimal thickening without lipid accumulation. The reduction in the number of intimal mast cells may play a part in the localization of atherosclerosis.

Adolescent↗
PubMed1979

Measurement of endothelial fibrinolytic activity in aorta and vena cava in rabbits: a fibrin-agar plate method.

The fibrin-agar plate method was used to estimate fibrinolytic activity from the luminal surfaces of aorta and vena cava with or without denudation of endothelium in rabbits. Diffuse endothelial denudation was accomplished by air-dry injury to the luminal surfaces for 24 hours prior to sacrifice. The segments individually obtained from the aorta and vena cava were immediately turned inside out in a cylindrical fashion and soaked in a vial containing plasminogen-rich solution. The vials were kept in a refrigerator at 4 degrees C for 4 hours. Five microliter of the solution was dropped on a fibrin-agar plate containing 0.08% fibrinogen (plasminogen free) and 1.4% agar in 0.01 M phosphate buffer with a pH of 7.4. A thrombin solution was then added to the plates, which were incubated for 18 hours at 37 degrees C in a moist chamber. The fibrinolytically digested areas revealed no comparative difference in fibrinolytic activity between the aorta and the vena cava either in the experimental or control group. However, a plasminogen activator was detected on the luminal surfaces of both the aorta and the vena cava with endothelial denudation as well as in normal controls. These results suggest that luminal fibrinolytic activity may be located not only in endothelial cells but possibly in other sources as well. Further examination of the interaction between the tissue activator and the inhibitor and determination of their localization are needed. Thrombogenesis may be an important factor in atherogenesis; in certain circumstances, detachment of the endothelial cells exposes underlying collagen fibrils and subsequently initiates the aggregation of platelets and cellular proliferation in the intima. There are, however, many unresolved questions concerning the precise mechanisms of development, resolution and organization of thrombi.

Animals↗
PubMed1978

Mitotic structure of aortic intimal cells induced by mechanical injury in swine.

Repair processes of the aortic wall have been studied electron microscopically after removal of the endothelium by an inflated balloon procedure in the thoracic aortae of swine. Initial responses after injury included a thrombotic reaction, the appearance of intimal cells over the denuded surface, and increased mitotic activity of medial cells adjacent to the dead cells by day 3. Cells which engaged in intimal thickening were classified as modified smooth muscle cells throughout the course of this investigation. Mitosis of intimal cells, which was initially observed at day 3, substantially increased at day 7 and decreased by day 14. Mitotic intimal cells contained the same cytoplasmic organelles as interphase modified smooth muscle cells. A detailed description of the paired cisternae as an ultrastructural feature of cell division of modified smooth muscle cells was provided. The paired cisternae were initially observed among the remnants of the nuclear envelope in late prophase; they remained at the periphery of the mitotic apparatus in meta- and anaphase, and finally attached themselves to the nuclear envelope of the daughter cells in late telophase.

Animals↗
PubMed1978

Aggravating factor in lupus nephritis; electron microscopic observation.

47 renal biopsies from 36 patients with SLE were examined in detail to compare with clinical courses and ultrastructural findings. Of 36 patients, 8 cases were free from renal involvement. The severity of electron dense deposits in glomeruli with lupus nephritis were generally well correlated with each clinical feature obtained. Moreover, mesangiocapillary cell proliferation was considered to be the main morphological promoting factor in poor prognosis of the lupus nephritis. Prominent circumferential subendothelial dense deposits were suggested to enhance to enhance the proliferation of mesangial cells, mostly with a mode of circumferential interposition. In each deposit with lapse of time and/or treatments, subepithelial deposits were gradually degraded to granular material but not lucent, though most subendothelial deposits rapidly disappeared without any remnant structure or with only a few flocculent materials. Mesangial deposits were mostly stabilized and rarely turned membranous.

Adolescent↗
PubMed1978

Isolated stenosis of the pulmonary artery branches--an autopsy case with review of the literatures.

A necropsy of a 21-year-old male with isolated stenosis of the pulmonary artery was presented. The pulmonary artery branches showed various fibrous thickening including atheromata and mural thrombi. Those findings appeared mostly in elastic and large muscular pulmonary arteries as well as in medium sized arteries, while the small arteries and arterioles remained in slight changes. Systemic large elastic arteries seemed to be small and showed atheromatous lesions similar to those of the main pulmonary arteries. Moreover, eight autopsy cases with pulmonary artery stenosis from the literature were shortly reviewed and some pathological findings as an aid for angiographic cardiovascular studies were discussed.

Adolescent↗
PubMed1976

Ultrastructural studies of experimental acute pancreatitis.

Acute pancreatitis was studied by electron microscopy after retrograde infusion of either trypsin, and/or beta-glucuronidase into the canine pancreatic duct. Marked changes were induced by the mixture of trypsin and beta-glucuronidase. (1) The acinar cells were initially excavated from the acinar lumen and formed cystic bodies in themselves. The cystic bodies were then disrupted at their marginal membranes, and the acinar cells were filled with a large amount of fibrillar materials which originated from the contents of the cystic bodies. At this time, the luminal margin of the acinar cells completely disappeared. (2) The cellular organellas and the intracellular fibrillar materials in the acinar cells were discharged into the interstitial space through the disrupted basal lamina. Infection in the pancreatic ductal system was considered to play an important role in the pathogenesis of acute hemorrhagic pancreatitis.

Acute Disease↗
PubMed1976

An autopsy case of Cronkhite-Canada syndrome.

An autopsy case of Cronkhite-Canada's syndrome characterized by diffuse gastrointestinal polyposis, alopetia, onychodystrophia and pigmentation of the skin is reported. The patient, 51 year-old-male, died with general weakness and pneumonia at 6 months after the first notice of alopetia anorexia and weight loss. Numerous and various sized polyps and polypoid lesions were revealed in the gastrointestinal tracts at the autopsy. The microscopic pictures of the lesions were composed of hyperplastic or papillary adenomatous polyps with hyperplasia of mucosa epithelium. In some of the lesions, the glands are cystically dilated containing mucous. Lymph vessels of thelamina propria and the submucosa benerked chronic inflammatory infiltrate was noted. The present report is described the histopathological findings of the gastrointestinal lesions with Cronkhite-Canada syndrome and discussed with literature.

Humans↗