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Biomedical subjects

Y Fukuda

Publications and source records attributed to Y Fukuda.

At least 685 records · Page 38Linked to original sources
PubMed1990

Optic nerve regeneration by peripheral nerve transplant.

We studied the morphology of regenerated retinal ganglion cells and their axons in adult rodents after axotomy and autologous transplantation of the sciatic nerve. Regenerated ganglion cells, backlabeled with rhodamine dextran, were of similar size to or larger than those of intact cells in control animals. Dendrites and occasionally axons as well showed abnormal morphologies in most cells, though some cells appeared quite normal. Cross-sections of the regenerated axons, observed by electron microscopy, were always attached to either the Schwann cell cytoplasm or the basal lamina. The immunoreactive structures to anti-laminin antibody were quite irregular in the cross-sectioned graft and, compared with those of the intact sciatic nerve, they were generally smaller. Their appearance closely resembled that of the basal lamina in the graft observed by electron microscopy. These observations, taken together, suggest that the laminin-rich basal laminae of Schwann cells are essentially important for the regeneration of retinal axons in adult rodents.

Animals↗
PubMed1990

Role of elastic fiber degradation in emphysema-like lesions of pulmonary lymphangiomyomatosis.

To study the pulmonary structural remodeling in pulmonary lymphangiomyomatosis, electron microscopy and light and electron microscopic immunohistochemical observations for elastin and alpha 1-antitrypsin were performed on five open lung biopsy samples. Lung specimens showed emphysema-like changes in areas of abnormally accumulated smooth muscle cells. In the alveolar walls having accumulated smooth muscle cells, elastic fibers were decreased in number, disrupted, granular, and occasionally accumulated. Ultrastructurally, elastic fibers in areas of smooth muscle cell accumulation showed poorly outlined amorphous components and a few microfibrils, and occasionally showed electron-dense granular deposits in and around the amorphous components. Spiraling collagen fibrils were frequently found associated with these abnormal elastic fibers. Immunohistochemistry for elastin showed even staining of amorphous components of elastic fibers in the areas of smooth muscle cell accumulation. alpha 1-Antitrypsin was also detected evenly in amorphous components of elastic fibers in the areas of smooth muscle cell accumulation. It is proposed that the emphysema-like lesions of lymphangiomyomatosis are mediated by the degradation of elastic fibers, and these degraded elastic fibers are related to an imbalance of the elastase/alpha 1-antitrypsin system similar to the probable pathogenesis of emphysema.

Adult↗
PubMed1990

Alveolar soft-part sarcoma of the tongue. Report of a case.

A case of alveolar soft-part sarcoma (ASPS) of the tongue in a 19-year-old boy is presented. He underwent a hemiglossectomy and received chemotherapy and has been free of disease for 3 years. The origin of intracytoplasmic periodic acid-Shiff(PAS)-positive crystals found in the tumor and the histogenesis of ASPS are briefly discussed.

Adult↗
PubMed1990

Birth of normal calves resulting from bovine oocytes matured, fertilized, and cultured with cumulus cells in vitro up to the blastocyst stage.

Bovine oocytes matured in vitro were fertilized in high proportions (92% of matured oocytes) by sperm capacitated with Ca ionophore A23187. Eight percent of inseminated oocytes that were denuded 96 h after insemination developed to the morula stage when cultured for 6-120 h after insemination with cumulus cells from the original oocytes. Inseminated oocytes denuded 96 h after insemination developed to the blastocyst stage when cultured with or without cumulus cells or in the conditioned medium from 96 h to 168-216 h after insemination (9.0%, 8.1%, and 6.8% of inseminated oocytes respectively). Six frozen-thawed blastocysts were transferred nonsurgically to 3 recipients (2 embryos/recipient). Two of the 3 recipients became pregnant, with one delivering live twins at term. Seven fresh blastocysts were transferred nonsurgically to 6 recipients (1-2 embryos/recipient). Three of the 6 recipients became pregnant, with 2 delivering live calves.

Animals↗
PubMed1990

Cell proliferation during the process of bleomycin-induced pulmonary fibrosis in rats.

To elucidate the relationship between cell proliferation and structural remodeling in pulmonary fibrosis, light and electron microscopy with immunohistochemistry for bromodeoxyuridine (BrdU) and morphometry for BrdU-positive cells were performed following a single intratracheal instillation of bleomycin in rats. The results showed that terminal bronchiolar epithelial cells, Type II alveolar epithelial cells and interstitial cells began to proliferate 2 days after the injury. Then each cell type showed a different style of proliferation. Interstitial cells which were located in the interstitium and migrated into intraalveolar spaces proliferated, then produced intra-alveolar fibrosis. Terminal bronchiolar epithelial cells proliferated rapidly and formed alveolar bronchiolization with squamous metaplasia in areas where alveoli were severely damaged and intraalveolar fibrosis was formed, and thereafter the proliferation ceased within 2 weeks. The degree of proliferation of type II alveolar epithelial cells and interstitial cells was rather slight, but continued constantly until the later stage. In addition, intraalveolar macrophages were BrdU-positive from an early stage. Endothelial cell proliferation was observed in small vessels and alveolar capillaries at 1 week after bleomycin instillation. Rapidly proliferating bronchiolar epithelial cells which formed alveolar bronchiolization with squamous metaplasia were important in preventing the progress of intraalveolar fibrosis, because the proliferation of type II alveolar epithelial cells was limited.

Administration, Oral↗
PubMed1990

Proliferation and intracellular pH in cultured proximal tubular cells.

Renal proximal tubule (PT) cells from adult rats will maintain much of their functional characteristics in short-term primary culture [S. Larsson, A. Aperia, and C. Lechene. Am. J. Physiol. 251 (Cell Physiol. 20): C455-C464, 1986]. This study examines the growth regulation of these highly differentiated cells with particular reference to cell density, intracellular pH (pHi), and the expression of the Na(+)-H+ exchanger. PT cells were obtained from young adult rats and studied after 48 h in culture. The mitotic rate was determined as the labeling index (LI) after [3H]thymidine autoradiography, and pHi was determined by 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein quantitative fluorescence microscopy in single cells. Cells were grown either continuously in serum (S) or were serum deprived after 24 h (D). The cells were nonconfluent and grew in colonies. We defined the two peripheral layers of cells in a colony as peripheral (P) cells and the remaining cells as central (C). In C cells LI/h and pHi were in the range of what has been observed under in vivo conditions. In S condition LI/h was 2.2 +/- 0.3% and in D condition was 0.3 +/- 0.1%. LI was significantly higher in P than in C cells both under S (2.5 +/- 0.4-fold) and D conditions (5.6 +/- 0.8-fold). The rapidly growing P cells had a significantly lower pHi than the growth-retarded C cells both under S (7.25 +/- 0.02 vs. 7.30 +/- 0.01, P less than 0.05) and D conditions (7.21 +/- 0.02 vs. 7.28 +/- 0.01, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

A case of Takayasu's arteritis associated with membranoproliferative glomerulonephritis and nephrotic syndrome.

We describe a 57-year-old Japanese female who had Takayasu's arteritis associated with nephrotic syndrome due to membranoproliferative glomerulonephritis. Although a focal and segmental mesangial proliferative glomerulonephritis associated with Takayasu's arteritis has been described, membranoproliferative glomerulonephritis has not been reported previously in this condition.

Aortic Arch Syndromes↗
PubMed1990

Changes in vasopressin, atrial natriuretic factor, and water homeostasis in the early stage of bronchopulmonary dysplasia.

Arginine vasopressin (AVP), atrial natriuretic factor, and water balance were examined in the infants with or without bronchopulmonary dysplasia (BPD) during the first 4 wk of life. Fourteen premature infants, nine in the early stage of BPD secondary to respiratory distress syndrome (BPD infants) and five healty low birth wt infants (LBW infants), were the subjects of this study. The water and sodium balance, renal function, and plasma AVP and atrial natriuretic factor concentrations were determined during the first 4 wk of life. Plasma AVP and atrial natriuretic factor levels of BPD infants at the 4th wk of life were higher than those of LBW infants at the corresponding age. Urine osmolality was higher and free water clearance was lower in BPD infants at the 4th wk of life when compared with each parameter in LBW infants, respectively. Paco2 of BPD infants at the 4th wk of life was more elevated than that of LBW infants. These results suggest that elevated plasma AVP level may be related with pulmonary abnormalities and that atrial natriuretic factor may hence compensate the water retention resulted from the functionally activated AVP in the early stage of BPD.

Arginine Vasopressin↗
PubMed1990

Caroli's disease associated with liver cirrhosis. An autopsy case.

Caroli's disease is one of the rare congenital conditions associated with the cystic dilatation of intrahepatic bile ducts. This is a case report of a 41-year-old Japanese male who complained of jaundice and general fatigue at the age of 34 for the first time. He was clinically diagnosed as having Caroli's disease by physical examination and image analyses study. The patient died after seven years and three months from the onset of the disease on account of renal function impairment. An autopsy was performed, revealing cystic dilatation of the intrahepatic bile duct, associated with a cirrhotic liver and also evidence of portal hypertension, substantiated by esophageal varices and splenomegaly. The liver weighed approximately 2,200 g. A histological investigation revealed typical morphological evidence of cirrhotic glomerulopathy and tubular degeneration with the presence of calcium casts in the dilated tubuli. The lung revealed diffuse alveolar damage with partial organization associated with remarkable polymorphonuclear and macrophagic infiltration. In this paper, the pathogenesis of the cirrhotic change, biliary duct abnormality and potential malignant transformation in the liver are discussed in relation to Caroli's disease.

Adult↗
PubMed1990

[Study on small renal cell carcinoma diagnosed by ultrasonography].

Sixty-seven patients underwent a resection of renal cell carcinoma in our hospital between July 1984 and Mar. 1989. Out of them 31 patients with small renal cell carcinoma less than 4 cm in diameter were examined. The proportion of small renal cell carcinoma to all renal cell carcinoma was 36% (14 patients) in the first half period (July 1984-July 1987) and 61% (17 patients) in the last half (Aug. 1987-Mar. 1989), i.e. in total more than half of all the carcinomas. The patients diagnosed by ultrasonographic screening were 25 (80%) out of the 31 patients. The incidence of small renal cell carcinoma was 4 (0.06%) out of 6892 patients in our health check-up center and 6 (1.0%) out of 610 hemodialysis patients, and they were found by ultrasonic examination. The carcinoma was protruded from the renal contour in 24 patients (77%) and was inside the renal parenchyma (23%) in 7 patients. The carcinoma in the 24 patients was associated with the deformity of its outline. The patients with a positive IVP were 5 out of 31 patients and the carcinoma in 4 out of the 5 patients was inside the renal parenchyma. Of all patients with protrusion of te renal contour, only one patient was with a positive IVP. The above findings indicate that ultrasonic examination is a useful method for the early diagnosis of small renal cell carcinoma.

Adult↗
PubMed1990

Prevalence of Cryptosporidium infection among domestic cats in the Tokyo Metropolitan District, Japan.

From February, 1988 to February, 1989, an epidemiological survey for feline cryptosporidiosis was carried out on domestic cats that had been committed to the Tokyo Metropolitan Animal Protection Center by owners residing in the Tokyo Metropolitan District. Of a total of 608 cats, 23 (3.8%) were found to have Cryptosporidium oocysts. The percentage of cats positive for the infection ranged from 0 to 13.6% by month. The infection was found to be more common in "baby" and "young" cats than in "middle" and "old" ones. No significant difference in incidence was shown between the sexes. In each positive cat, no apparent clinical symptom such as diarrhea was found, and the size of the oocysts measured from 4.3 to 4.7 microns in diameter (small type).

Age Factors↗
PubMed1990

[Coronary artery bypass grafting with combined arterial grafts].

Coronary artery bypass grafting with combined arterial graft using the left internal mammary artery (IMA), right IMA, and the right gastroepiploic artery (GEA) was performed in 45 patients with saphenous vein graft (SVG) (29 patients) or without SVG (16 patients) from February 1989 to October 1989. The left IMA was used in all patients, the right IMA was used in 9 patients, and the GEA was used in 43 patients. Perioperative myocardial infarction was noted in two patients who had hospital deaths. Reopening the chest for postoperative bleeding was performed in two patients, and the cerebral accident was noted in one patient. Fourteen patients were operated on without the requirement for blood transfusion. Studied within 3 postoperative months, all arterial grafts were patent though the patency was 97.7% (43/44) in SVG. It is concluded that the combined arterial graft utilizing the IMAs and GEA can be used safely and effectively.

Adult↗
PubMed1990

[Analysis of pleural plaque found at lung cancer screening examination].

In the screening test of lung cancer, we found that there was a high prevalence of cases with pleural plaque recognized by chest X-ray film in inhabitants living in A town in Kumamoto Prefecture. We detected abnormal pleural plaque in 148 (41.5%) of 357 cases received lung cancer screening. These pleural plaques resulted in pleural thickening and calcification. Two or three mines of serpentine and an asbestos factory existed in this region from 1883 until 1970. Although twelve cases had a history of factory work, none had fibrous changes in the lung fields on chest X-ray films. It was considered that the pleural plaque probably resulted from exposure to low doses of asbestos in the atmosphere or contact with asbestos workers in their homes. The incidence of lung cancer in this region was not higher than that in other regions in Kumamoto Prefecture. There were no cases of malignant mesothelioma in our hospital during the past eleven years.

Adult↗
PubMed1990

Antihypertensive mechanism of action of the novel angiotensin converting enzyme inhibitor benazepril. Effect on isolated vascular preparations.

Benazepril (CGS 14824A HCl) is a new prodrug type angiotensin converting enzyme (ACE) inhibitor. The active form is considered to be benazeprilat, a diacid hydrolyzed compound. Benazepril and benazeprilat inhibited the contraction induced by exposure with angiotensin I, not angiotensin II, in the isolated rabbit aorta. The ACE inhibiting activity of benazeprilat was 1000 times more potent than that of benazepril in this experiment. Benazepril as well as benazeprilat and captopril exerted little influence on norepinephrine, serotonin and high K(+)-induced contraction or bradykinin-induced relaxation in isolated blood vessel preparations, thus angiotensin II synthesis inhibition seemed to be the main cause for its vasodilation. Benazepril, unlike benazeprilat or captopril showed considerable influence on prostaglandin (PG)-induced responses at higher concentrations. The vasocontraction induced by PGF2 alpha was competitively antagonized at 10(-5)-10(-4) mol/l, while vascular responses induced by PGE1, PGE2 or PGI2 was inhibited at 3 x 10(-4) mol/l of benazepril. Although these influences on PGs might not contribute much to its vasodilatory mechanism, the action seemed interesting in relation to cough induction, a known side effect of ACE inhibitors in the market. Benazepril has two asymmetric carbon atoms, thus four optical isomers are possible, SS (benazepril), SR (CGP 14'829A), RS (CGP 42'454A), RR (CGP 42'456A). The SS configuration was the most potent for antagonizing angiotensin I-induced vasocontraction, which seemed to be the best fitted for the ACE molecule.

Alprostadil↗
PubMed1990

[Upper airway: innervation and chemical regulation of respiration].

The general physiology of respiratory function of upper airway muscles is presented. Comparative aspects of upper airway structure and of breathing mechanism are discussed briefly. Contribution of upper airway inspiratory muscle activity and roles of muscle activity during post inspiratory phase are described. The activity of upper airway muscles or innervating cranial nerve motoneurons and their alteration by chemical stimuli are greatly modified by vagal pulmonary afferents. Functional significance of these changes during upper airway obstruction are discussed.

Animals↗