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Biomedical subjects

M Ueda

Publications and source records attributed to M Ueda.

At least 289 records · Page 16Linked to original sources

Mast cell chymase in pulmonary hypertension.

Mast cells are known to be involved in various types of tissue remodelling but their role in pulmonary hypertension is still poorly understood. Two subtypes of mast cells have recently been identified by demonstrating one protease, chymase. This enzyme might be implicated in vascular remodelling. The changes in mast cells in lung tissue from three patients with primary or secondary pulmonary hypertension were therefore investigated. Compared with tissue from four control subjects the number of mast cells in the three patients was markedly increased, which suggests that chymase containing mast cells are involved in tissue remodelling accompanied by fibrotic changes in primary and secondary pulmonary hypertension.

Adult↗

Mitochondrial injuries in rat lungs preserved for 17 h: An ultrastructural study.

Mitochondria of the small vasculature endothelial cells were examined in preserved rat lungs before and after reperfusion, and the ultrastructural changes were correlated with pulmonary function after reperfusion. Rat lungs were flushed with perfusate and prostaglandin E1 and divided into five groups (n = 5 in each group): group A, normal control group; group B, University of Wisconsin solution; group C, Euro-Collins solution; group D, ET-Kyoto solution, and group E, new ET-Kyoto solution. After preservation at 4 degrees C for 17 h, the left lungs were reperfused at 37 degrees C for 60 min. Tissue was sampled and mitochondria of the small vasculature endothelial cells were ultrastructurally analyzed by transmission electron microscopy before and after reperfusion. The ultrastructure of the mitochondria was well maintained in groups A, B and E before and after reperfusion. In group C, the number of severely degenerated mitochondria in the sectional area of 100 microm2 before reperfusion was 18.0 +/- 3.9, which was significantly larger than in the other groups (p < 0.01), and the total number of mitochondria significantly decreased with reperfusion (from 24.8 +/- 3.5 to 8.2 +/- 2.4, p < 0.05). In group C, the shunt fraction, mean pulmonary arterial pressure and the wet-dry ratio of the lung tissue after reperfusion C were significantly higher than in the other groups (p < 0.05; 76.3 +/- 1.5%, 54.8 +/- 4.2 mm Hg, and 20.6 +/- 2.5, respectively). A positive correlation was found between the percentage of the mitochondrial degeneration before reperfusion and the physiological parameters after reperfusion. Mitochondrial damage associated with cold ischemia is probably involved in lung injury caused by cold preservation and reperfusion.

Animals↗

Biological implications of growth factors on the mechanism of invasion in gynecological tumor cells.

We investigated the effects of epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) on migration, invasion and proteinase expression of gynecological cultured cancer cells (SKG-IIIb cervical squamous cell carcinoma, OMC-4 cervical adenocarcinoma, SNG-M endometrial adenocarcinoma and OMC-3 ovarian adenocarcinoma), and whether these growth factors affect thymidine phosphorylase/platelet-derived endothelial cell growth factor expression of tumor cells. Tumor cell migration along a gradient of substratum-bound fibronectin and invasion into reconstituted basement membrane were stimulated by 0.1-10 nM EGF and TGF-alpha in a concentration-dependent manner. The zymography of tumor-conditioned medium showed that the treatment of tumor cells with EGF and TGF-alpha resulted in the increase of type IV collagenases, stromelysin and urokinase-type plasminogen activator which was partly confirmed by immunoblot analysis. The expression of thymidine phosphorylase/platelet-derived endothelial cell growth factor which has angiogenic activity, was also upregulated by these growth factors. These results suggest that EGF and TGF-alpha act as positive regulators on the invasion process of gynecological tumor cells which may be associated with their stimulatory action on the motility of tumor cells, the expression of proteinases secreted by tumor cells and the angiogenic phenotype.

Adenocarcinoma↗

Central nervous system-mediated hyperglycemic effects of NIK-247, a cholinesterase inhibitor, and MKC-231, a choline uptake enhancer, in rats.

We investigated the effects of intracerebroventricular administration of NIK-247 (9-amino-2,3,5,6,7,8-hexahydro-1H-cyclo-penta(b)-quinoline monohydrate hydrochloride; a cholinesterase inhibitor) or MKC-231 (2-(2-oxypyrrolidin-1-yl)-N-(2,3-dimethyl-5,6,7,8-tetrahydrofur o[2,3-b]quinolin-4-yl) acetoamide; a choline uptake enhancer) on plasma glucose level in comparison with that of neostigmine administration in rats. The extents of NIK-247- and MKC-231-induced hyperglycemia were considerably less than that by neostigmine, suggesting that the potencies of the drugs to produce the peripheral hyperglycemia may be pharmacologically negligible.

Aminoquinolines↗

Establishment of SV40-tsA58 transgenic rats as a source of conditionally immortalized cell lines.

To isolate a variety of rat cell lines with differentiated functions, we established transgenic rat lines expressing the temperature-sensitive large T-antigen of simian virus 40 (SV40) tsA58 mutant under the control of the SV40 large T-antigen itself. We microinjected the DNA into 564 eggs of Wistar rat and 23 independent transgenic candidates were obtained. Ten pups died before weaning and eight transgenic rats could not transmit the transgene to the progeny. Finally, five lines of the transgenic rat were established. Although one line (#1511-6) had low reproductivity, the other four lines reproduced normally. Three out of the four lines (#1507-2, #1509-7, #1519-8) appeared normal but the other line had tumors in the brain and subcutaneous tissue at 3 weeks of age (#1511-6), and in the kidneys and subcutaneous tissue at 18 to 19-weeks of age (#1507-5). Fibroblast cells prepared from transgenic fetuses of lines #1507-5 and #1519-8 expressed the transgene and exhibited temperature-dependent growth. Both of the lines (#1507-5 and #1519-8) were successfully generated to be homozygous by sibling mating of transgenic offspring. These transgenic rat lines have bred through many generations and have been established to be a ready source of novel conditionally immortalized cell lines.

Animals↗

Incidence of skin cancers and precancerous lesions in Japanese--risk factors and prevention.

An examination of the occurrence of skin cancers and precancerous lesions among residents of Kasai City (34 degrees 56' N) since 1992, and of le-island (25 degrees 10' N) since 1993, has been conducted to characterize the prevalence and incidence of skin cancers in Japanese people and to evaluate risk and preventive factors. The mean prevalence of actinic keratosis (AK) in residents of Kasai City and le-island was 203.33 and 756.26, respectively, indicating that twice the dose of UVB radiation causes a 3-4 fold higher incidence of AK, although life styles, including types of occupations, differ in these two locations. Working outdoors, having skin type I and/or a history of severe sunburns during childhood were found to be important risk factors, while the use of cosmetics after 20 years of age was a protective factor, for AK and possibly for skin cancers. Further, sunscreen use among males over 60 years of age in Kasai City from 1994 through 1998 suggested that sunscreen use may reduce AK development in older people. Four and 12 cases of skin cancers were found in residents of Kasai City (from 1992 to 1997) and on le-island (from 1993 to 1998), respectively. These numbers are too small to establish the prevalence of skin cancer in Japanese, but indicate that people living in areas of higher ambient solar radiation have a higher incidence of skin cancer. This epidemiological study strongly indicates that sun protection is the major modality to reduce sun-induced cutaneous tumors in Japanese.

Adult↗

Successful transfer of localized autoimmunity with positively selected CD4+ cells to scid mice lacking functional B cells.

T-cell function of athymic BALB/c-nu/nu (nude) mice can be corrected by implantation of a embryonic rat thymus graft (TG) under the renal capsule (TG nude mice). However, multiple organ-localized autoimmune diseases, such as oophoritis, Sjögren's syndrome like disease and gastritis, develop spontaneously in TG nude mice. Transfer of spleen cells from TG nude mice with such diseases leads to multiple localized autoimmune lesions with appearance of the corresponding autoantibodies in the recipient C.B-17-scid (SCID) mice. In the present study, removal of CD90+ or CD4+, but not CD8+ cells eliminated the transfer activity. Positively selected CD4+ cells proved capable of inducing lesions without the appearance of organ-specific autoantibodies, although the grade of lesions was lower than that in recipient mice that received untreated or CD8-depleted spleen cells. Target organs demonstrating CD4+ cell infiltration, generally expressed major histocompatibility complex (MHC) class II antigen (Ia) on their parenchymal cells. Injection of sera from TG nude mice with autoantibodies to SCID mice did not induce any pathogenic features in the autoantibody-target organs, although deposition of immunoglobulins in the corresponding target organs was observed. In such cases, no Ia antigens were expressed on the parenchymal cells. The data thus indicate that effector CD4+ cells can induce autoimmunity without B-cell help but that cooperation with functional B cells induces more severe tissue damage.

Animals↗

Combined effects of ethanol and garlic on hepatic ethanol metabolism in mice.

The combined effects of ethanol and components in fresh garlic on ethanol metabolism were investigated in the livers of mice. Male, 11-wk-old C3H/HeNCrj mice were intragastrically administered 2 g ethanol/kg body weight after being administered fresh garlic juice for 8 d (garlic group), and changes in the concentrations of ethanol, acetaldehyde and acetate in the serum, and changes in the activity of hepatic enzymes related to ethanol metabolism in mice were examined. The increases in the concentrations of acetaldehyde and acetate in the serum after ethanol administration tended to be diminished following garlic administration. The microsomal ethanol-oxidizing system (MEOS) in the livers of the garlic groups was significantly lower than that of the control microsomes at 2 h after ethanol administration. It therefore seems that the decrease of MEOS in hepatic microsomes caused a smaller increase in the acetaldehyde concentration in the serum of the garlic groups because cytosolic alcohol dehydrogenase showed no significant difference between the control and garlic groups. After ethanol administration, the content of cytochrome P-450 in the hepatic microsomes of the control groups increased, while that of the garlic groups did not change although cytochrome P-450 (CYP) 2E1 and 1A2 in the hepatic microsomes of the garlic groups increased. These results indicate that the induction of isozymes of cytochrome P-450 other than CYP 2E1 and 1A2 was inhibited following garlic administration. Cytosolic high Km and total aldehyde dehydrogenase (AIDH) in the liver of the garlic groups tended to be lower than those activities of the control groups at 1 and 2 h after ethanol administration. It therefore seems that the decreases of AIDH in the hepatic cytosols diminished the increase of acetate in the serum of the garlic groups after ethanol administration. These results suggest that the ethanol metabolism in the mouse liver is controlled by components in fresh garlic juice.

Acetaldehyde↗

Trichofolliculoma of the upper lip: report of a case.

A trichofolliculoma occurring in the mid-philtrum of the upper lip of a 17-year-old boy is reported. It presented as an asymptomatic, 10 mm deep sinus and histology showed keratin-filled cysts or sinuses lined by stratified squamous epithelium.

Adolescent↗

Alveolar ridge augmentation by distraction osteogenesis using titanium implants: an experimental study.

The left mandibular premolars were extracted from five adult dogs. After twelve weeks, a box-shaped osteotomy of the alveolar bone was carried out and two 10 mm implants were placed 5 mm into the transport alveolar segment, leaving 5 mm exposed. The alveolar bone was vertically augmented 5 mm by screwing the implants. After distraction, the implants were left to integrate into the bone. Histological and radiographical evaluations showed the lifting of the transport segment and the development of new bone in the distraction area. Although integration of implants within both the transport segment and the regenerated bone was observed, two of the ten implants failed and partial bone resorption of the transport segment was noted.

Alveolar Process↗

Centrosomes, microtubules and cell migration.

Directed cell movement is an immensely complex process that depends on the co-operative interaction of numerous cellular components. Work over the past three decades has suggested that microtubules play an important role in the establishment and maintenance of the direction of cell migration. This chapter summarizes recent work from our laboratory designed to determine the roles of the microtubules and centrosome position relative to the direction of cell migration in a variety of cell types, and discusses these observations in the context of work from other laboratories. The results suggest that microtubules are required for stabilization of the direction of migration in many, but not all, cell types. For the centrosome to act as a stabilizer of cell migration requires that it is repositioned behind the leading edge. However, the process of repositioning does not precede the extension of a leading edge and the establishment of a new direction of cell migration. Rather, the centrosome follows the repositioning of the leading edge in response to other stimuli and, in doing so, stabilizes cell movement.

Animals↗

[Molecular alterations in Barrett's esophagus and adenocarcinoma].

Patients with Barrett's columnar-lined esophagus are at increased risk of developing esophageal adenocarcinoma, the incidence of which has increased rapidly especially in the USA. Although the number of patients with Barrett's adenocarcinoma is fewer in Japan than in the USA, all gastroenterologist should know its multistep carcinogenic process. Tumor suppressor genes (p53, p16), oncogenes (c-erbB-2, H-ras, K-ras, cyclin D1, src), and growth factor/receptor (TGF-alpha, EGFR) seem to cause the malignant transformation of Barrett's esophagus. Because detection of these molecular alterations is feasible, more accurate diagnosis of Barrett's esophageal biopsy specimens should be made by adding the molecular examination to the conventional pathologic examination.

Adenocarcinoma↗

[Onset of acute eosinophilic pneumonia after resumption of smoking].

We report a case of acute eosinophilic pneumonia (AEP) apparently caused by the resumption of smoking. A 38-year-old woman was admitted to our hospital because of dry cough, high fever and chest pain. Arterial blood gas analysis revealed pronounced hypoxemia and chest X-ray film disclosed diffuse bilateral infiltrate throughout all lung fields. Eosinophils (43.7%) were significantly increased in bronchoalveolar lavage fluid (BALF). The patient was treated with pulse therapy consisting of methylprednisolone and improved quickly. AEP was diagnosed on the basis of BALF findings and the patient's clinical course. Prior to and after her illness, the only noteworthy change in the patient's environmental setting or habits was the resumption of smoking, 3 days after which the symptoms had appeared. We reasoned that the onset of AEP in this patient was strongly related to the resumption of smoking.

Adult↗

[Risk factor of liver disorders caused by flutamide--statistical analysis using multivariate logistic regression analysis].

The antiandrogenic drug, flutamide (Odyne), is widely used in the treatment of carcinoma of prostate. It is well known that flutamide has adverse effects of liver disorders. To ascertain the risk of liver disorders before administering this drug, past history and lifestyle preferences were resurveyed in 123 patients who had been treated with flutamide. The results obtained were assessed in relation to the occurrence of liver disorders by multivariate logistic regression analysis. The incidence of liver disorders was 26% (33/123), with 64% of the disorders occurring within 9 months. The chi-square test for dependent variables revealed that three variables, i.e., body mass index, past history of liver disorders and elevated glutamic-pyruvic transaminase levels were significantly related to the incidence of liver disorders (p > 0.05). Multivariate analysis indicated that a history of liver disorders and elevated alanine aminotransferase (ALT) levels were related to a higher incidence of liver disorders. Elevated ALT levels were associated with a higher incidence of liver disorders and smoking was related to a lower incidence of the liver disorders.

Alanine Transaminase↗