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Y Miyamoto

Publications and source records attributed to Y Miyamoto.

At least 127 records · Page 7Linked to original sources

[In vivo toxicity, and glutathione, ascorbic acid and copper level changes induced in mouse liver and kidney by copper(II) gluconate, a nutrient supplement].

While copper(II) gluconate (CuGL) is generally used as a nutrient supplement for infant foods and as an oral deodorant, little information is available regarding a toxic effect of CuGL on mammals. In this article, we examined in vivo induction of toxicity and change of level of glutathione and ascorbic acid, major biological antioxidants, lipid peroxide and copper (Cu) in liver and kidney 4 h after single intraperitoneal administration of CuGL at 0.05 and 0.10 mmol/kg to mice. Serum glutamic pyruvic transaminase (SGPT) activity, an indicator of hepatotoxicity, significantly increased compared to control in proportion to doses of CuGL. Hepatic level of glutathione measured as nonprotein sulfhydryl was not proportional to CuGL doses, but enhanced after dosing of 0.05 mmol/kg and lowered by 0.10 mmol/kg. Like SGPT activity, serum urea nitrogen (SUN) concentration, an indicator of nephrotoxicity, significantly increased in proportion to doses of CuGL. Renal glutathione level was not different from control after dosing of 0.05 mmol/kg and lowered by 0.10 mmol/kg. In both organs, relative organ weight and lipid peroxide level were not affected by the treatment with CuGL; ascorbic acid level was elevated after dosing of 0.05 mmol/kg and was not different from control after treatment with 0.10 mmol/kg; like SGPT activity and SUN concentration, Cu level significantly increased in proportion to doses of CuGL. These results suggest that in the liver and kidney after the treatment with CuGL Cu accumulated may induce toxicity, leading to level changes of glutathione and ascorbic acid and to no induction of oxidative damage.

Animals↗

Endothelial nitric oxide synthase gene mutation and human leukocyte antigen analyzed in three cases of familial vasospastic angina pectoris.

A 50-year-old woman with rest angina underwent cardiac catheterization; coronary angiography in the presence of acetylcholine revealed 99% coronary spasm of the proximal left anterior descending artery. The patient's 82-year-old mother was also admitted to hospital with rest angina. Her Holter electrocardiogram showed ST-segment elevation during the attack at rest and coronary angiography showed 99% spasm of the right coronary artery and 90% spasm of the left coronary artery. Both women complained of chest pain during the spasm, which was accompanied by ST-segment depression. The 62-year-old brother of the original patient was also found to have coronary spasm of the left coronary artery. Human leukocyte antigen was analyzed in the 2 women: A2, B51, CW1, DR8 and DQ1 were common factors. A Glu298Asp point mutation of the endothelial nitric oxide synthase gene was investigated in both parents, their 2 daughters and 2 sons, but was not detected in the 3 patients, and was detected only in the 90-year-old father who did not suffer from angina. Nor was the T-786-C mutation found in the 3 cases. Other causes of familial spasm need to be elucidated.

Aged↗

Identification of a taurine transport inhibitory substance in sesame seeds.

An ethanol extract from sesame seeds inhibited the taurine uptake in human intestinal epithelial Caco-2 cells. The uptake of such alpha-amino acids as leucine and glutamic acid was not inhibited by the extract, indicating that this inhibition is specific to the taurine uptake. The unknown inhibitor in the sesame extract was purifled by reversed-phase HPLC by monitoring the inhibitory effect on taurine uptake. The isolated substance was identified as lysophosphatidylcholine, linoleoyl (Lyso-PC), by NMR and MS analysis. Lyso-PC inhibited the taurine uptake in a dose-dependent manner with an IC50 value of approximately 200 microM. Although Lyso-PC is known to be a surface active and cell lytic compound, neither damage nor loss of integrity of the Caco2 cell monolayer was apparent after treating with 200 microM Lyso-PC. Inhibition was observed by incubating cells with Lyso-PC for only 1 min prior to the uptake experiments. These results suggest the direct effect of Lyso-PC on the cell membrane to be the main mechanism for this inhibition. Lyso-PC may play a role in the regulation of certain intestinal transporters.

Biological Transport, Active↗

Lack of association between T-786-->C mutation in the 5'-flanking region of the endothelial nitric oxide synthase gene and essential hypertension.

Accumulating evidence strongly suggests that an alteration in nitric oxide metabolism is involved in the pathogenesis of hypertension. We recently found 2 polymorphisms in the endothelial nitric oxide synthase (eNOS) gene, a Glu298Asp missense variant in exon 7 and a T-786-->C variant in the 5'-flanking region, which are not linked to each other. In our previous reports, we showed a positive association between the Glu298Asp variant and essential hypertension, myocardial infarction, and coronary spastic angina. We also revealed that the T-786-->C variant is strongly associated with coronary spastic angina and leads to the reduction of the eNOS gene promoter activity. To further investigate the genetic involvement of the eNOS gene in essential hypertension, we examined the frequency of T-786-->C variant in two independent populations of persons with essential hypertension in Kyoto (n=215) and Kumamoto (n=186) and compared the frequency with that in each age- and gender-matched control (233 controls in Kyoto and 223 controls in Kumamoto). In both groups, the frequency of T-786-->C variant was similar in patients with hypertension and normal controls. In conclusion, the T-786-->C variant was not positively associated with essential hypertension. Given the evidence of positive association of another polymorphism in the eNOS gene, the Glu298Asp polymorphism, with essential hypertension, special attention will be required to interpret the results of a case-control study for genetic risk factors.

Adult↗

Apoptosis and cell proliferation in rat hepatocytes induced by barbiturates.

To examine the effect on cell population in hepatocytes of phenobarbital (PB) and other barbiturates, PB, allobarbital (ALB), barbital sodium (BS) and barbituric acid (BA) were given orally to male rats for 7 consecutive days. Although there was no apparent change in non-promoting BA, hepatomegaly was induced by PB, BS and ALB, which are promoters of hepatocarcinogenesis. In PB- and BS-treated livers, hepatomegaly was attributable to hepatocyte proliferation and enzyme induction. In ALB-treated liver, it was attributable to enzyme induction. The level of cell proliferation was reduced to less than the control values following withdrawal of PB, ALB and BS. It seemed that the degree of suppression of cell proliferation following withdrawal of these compounds correlated to the degree of cell proliferation (PB>BS>ALB) during treatment. In PB-treated liver, apoptosis was induced during treatment, serving to eliminate the excess of hepatocytes. This suggests that short-term administration of PB neither induced suppression of apoptosis nor disturbed homeostasis of hepatocyte populations.

Animals↗

Generalized algorithm for the unified analysis and simultaneous evaluation of geometrical spin-redirection phase and Pancharatnam phase in a complex interferometric system.

To permit unified analysis and simultaneous evaluation of geometrical spin-redirection phase and Pancharatnam phase, the conventional 2 x 2 Jones matrix calculation is generalized and a new scheme of 3 x 3 matrix calculation is proposed. With the proposed algorithm one can trace the polarization state changes and the geometric phase shifts caused by beam propagation along an arbitrary optical path that involves both reflection and refraction at surfaces with Fresnel shift and birefringence.

Algorithms↗

Induction therapy for non-small cell lung cancer with involved mediastinal nodes in multiple stations.

BACKGROUND: Metastasis to multiple stations of mediastinal nodes is associated with a poor prognosis. OBJECTIVE: : We prospectively examined the efficacy of induction therapy plus surgery in patients with non-small cell lung cancer and metastases at multiple stations of mediastinal (N2) lymph nodes. METHODS: Among the 1,085 patients who underwent surgery for primary non-small cell lung carcinoma from 1985 to 1997, those with clinical N2 disease of involved multiple stations, defined as bulky, mediastinal, lymph node metastases on CT scans, received induction therapy, consisting of cisplatin-based chemotherapy and radiation of 40 Gy. RESULTS: Of the 88 eligible patients entered into the study, 51 (58%) had multiple stations of N2 nodes affected preoperatively, as demonstrated by pathologic examination. Neither operative mortality nor fatal, treatment-related complications occurred during hospitalization. Patients who underwent complete resection had significantly longer survivals than did those who underwent incomplete resection (p = 0. 001). Among patients who underwent complete resection, the survival rate for patients with pathologically downstaged disease was significantly higher than that for patients whose disease was not downstaged (p = 0.009). Among patients with multiple stations of pN2 nodes involved who had undergone complete resection, those who received induction therapy for bulky N2 disease had a significantly better prognosis than did those undergoing surgery alone for nonbulky N2 disease (p = 0.03). CONCLUSIONS: Induction therapy prolonged the survival of patients with non-small cell lung cancer and mediastinal nodes involved at multiple stations. Survival was better when complete resection and downstaging of the disease were achieved after induction therapy.

Adult↗

Lung cancer in women: sex-associated differences in survival of patients undergoing resection for lung cancer.

STUDY OBJECTIVES: The aim of this study was to analyze various characteristics and survival in female patients treated surgically for lung cancer. DESIGN: Retrospective clinical study. PATIENTS: From 1,242 consecutive cases of primary non-small cell lung cancer treated with pulmonary resection between June 1984 and December 1998, 337 female patients (27.1%) were chosen. RESULTS: Female patients had the following characteristics: a significantly younger age at onset (62.5 +/- 0.56 years vs 64.1 +/- 0.31 years for men), a higher frequency of adenocarcinoma (86.0% vs 48.3% for men), and smaller tumors (32.7 mm vs 38.3 mm in diameter for men). Peripheral tumors were significantly more common in women than men (71.8% vs 50.6%, respectively). Among 686 patients with a history of smoking, the women smoked significantly less often (12.8% vs 91.4% for men). Complete resection was achieved significantly less often in women (79.6% vs 85.2% for men); however, women having complete resection survived significantly longer than their male counterparts. Women with a postoperative negative carcinoembryonic antigen (CEA) had a significantly better prognosis than men; however, women with a postoperative positive CEA did not. Women > or = 60 years old survived significantly longer than their male counterparts, while women < 60 years old did not. CONCLUSIONS: Once the tumor was resected completely, women survived longer, partly due to the influence of life expectancy. However, the incidence of malignant effusion was higher and the rate of complete resection was lower in women.

Carcinoembryonic Antigen↗

Immunohistochemical analysis of apoptosis-related proteins in human embryonic and fetal pancreatic tissues.

BACKGROUND: The growth of both cancer cells and fetal tissue is rapid; however, cancer cells de-differentiate and proliferate in a disorderly manner, whereas fetal tissues differentiate and proliferate in an orderly manner. Thus, there may be both common and different factors that are involved in the process of the uncontrolled cell growth of pancreatic cancers and the development of the fetal pancreas. The common part of the mechanisms should be in the regulation of the cell cycle, resulting in rapid proliferation via such mechanisms as growth stimulation and avoidance of apoptosis. Therefore, in the current study we investigated the expression of apoptosis-related proteins in fetal pancreatic tissues. METHODS: Sixteen human embryonic and fetal pancreatic tissues obtained between 6 and 32 wk of gestation were used. We immunohistochemically examined the protein expression of Bcl-2, Bcl-XL, Mcl-1, and Bax. Further, the expression of insulin, glucagon, and proliferting cell nuclear antigen (PCNA), and TdT-mediated dUTP-biotin nick-end labeling (TUNEL) staining were examined. RESULTS: In embryonic and fetal pancreatic tissues, Bcl-2 was not detected in any type of pancreatic cell (acinar, ductal, or islet). Bcl-XL was expressed in all types of pancreatic cells throughout the gestation. Mcl-1 was expressed in all types of pancreatic components, and strongly expressed in the margin of the islets. Bax, a pro-apoptotic protein, was expressed in all components. PCNA was strongly expressed in the embryonic and fetal pancreas, especially in early stages of gestation; however, TUNEL staining was negative in all samples. At least one antiapoptotic protein was expressed in all types of pancreatic cells. CONCLUSION: The results of the current study indicate that active proliferation and avoidance of apoptosis take place in embryonic and fetal pancreatic tissues, which may be controlled by particular combinations of apoptosis-related proteins. Among these proteins, Bcl-XL and Mcl-1 may play an important role in the proliferation and differentiation of the embryonic and fetal pancreas.

Apoptosis↗

Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats 2). Testicular toxicity in rats treated orally with ethinylestradiol for 2 weeks.

Parameters of ethinylestradiol-induced testicular toxicity were evaluated with organ weight determination, histopathological examination and quantitative morphometry. Male Sprague-Dawley rats were administered ethinylestradiol orally at 3 or 10 mg/kg/day for 2 weeks and 3 mg/kg/day for 4 weeks. Final body weights in all treated groups were lower than in the respective control group. Decreased absolute and/or relative organ weights of epididymides, prostate, seminal vesicles and testes were observed in all treated groups. In the testes, apoptosis of round spermatids, atrophy of seminiferous tubules, exfoliation of spermatids or spermatocytes, and vacuolar degeneration of Sertoli cells were only observed with 4 weeks treatment. Apoptosis of pachytene spermatocytes and atrophy of Leydig cells were also more marked in the 4 week treated group than after 2 weeks. Therefore, degenerative histopathological changes in testes were more remarkable after 4 weeks treatment than in the 2 weeks treatment groups. However, retention of spermatids was less after 4 weeks treatment and the TUNEL index, calculated as the number of TUNEL-positive spermatocytes or spermatids, was increased in all treated groups. These results suggest that ethinylestradiol-induced testicular toxicity can be detected in male rats administered the compound for 2 weeks and that the TUNEL method for in situ detection of apoptosis is effective for evaluation of testicular toxicity.

Administration, Oral↗

Production of a new hybrid anthracycline 4-O-methylepelmycin by heterologous expression of dnrK in epelmycin-producing Streptomyces violaceus.

A new hybrid anthracycline antibiotic was produced by heterologous expression of dnrK encoding carminomycin 4-O-metyltransferase in an epelmycin-producing Streptomyces violaceus. pMK100 was constructed by insertion of Steptomyces peucetius dnrK gene in Steptomyces-expression vector pIJ6021 and introduced to the epelmycin producer. The transformant produced a hybrid anthracycline antibiotic together with host epelmycins when cultured in antibiotic production medium in the presence of thiostrepton. The hybrid anthracycline was determined to be 7-O-L-rhodosaminyl-4-O-methyl-epsilon-rhodomycinone (4-O-methylepelmycin D). However, the attempts on production of hybrid 4-O-methylaclarubicin and 4-O-methyl-1-deoxyobelmycin by the transformants of aclarubicin and 1-deoxyobelmycin producers with pMK 100 were unsuccessful.

Animals↗

Power Doppler sonography of breast masses: correlation of Doppler spectral parameters with tumor angiogenesis and histologic growth pattern.

The purpose of this study was to examine the relationship between spectral analysis on power Doppler sonography and microvessel density. Power Doppler sonography was performed in 71 patients with breast masses (36 invasive carcinomas and 35 benign lesions). Microvessel density was measured in surgical specimens from all breast carcinomas using anti-factor VIII-related antibody. Invasive carcinomas were divided into two groups according to their growth pattern (solid type, scirrhous type). The pulsatility index and resistive index were high in malignant tumors compared with those in benign lesions (P < 0.001). The maximum velocity had weak statistical significance (P < 0.05). Although the correlation of maximum velocity with microvessel density was strong in solid tumors (P < 0.001), the maximum intensity in scirrhous tumors had no correlation with microvessel density. In conclusion, solid tumors showed a tendency toward correlation of maximum velocity with microvessel density. High maximum velocity with high microvessel density suggests breast carcinoma and could be predictive of a poor prognosis in invasive breast carcinoma.

Adult↗

Auto-induction and growth stimulatory effect of betacellulin in human pancreatic cancer cells.

Betacellulin (BTC) was identified in mouse pancreatic beta cell tumors as a member of the epidermal growth factor (EGF) family, and was found to bind and activate the EGF receptor. BTC is also expressed in some human malignancies and may have an important role in tumor growth progression. We examined whether BTC and EGF have a growth stimulatory effect on human pancreatic cancer cell lines both in vitro and in vivo. We also investigated the BTC expression and autonomous induction of BTC in pancreatic cancer cells. in vitro, both BTC and EGF had almost the same proliferative effect on Panc-1, MIA PaCa-2 and AsPC-1. in vivo, in a Panc-1 inoculated athymic mice model, BTC-treated tumors grew approximately five times larger than in control. Immunocytochemistry showed that BTC expression occurred in three pancreatic cancer cell lines, with MIA PaCa-2 showing the strongest intensity. Semi-quantitative RT-PCR of MIA Paca-2 showed that mRNA levels of BTC gradually increased after treatment with 1 nM BTC. Immunocytochemistry also demonstrated that the intensity of BTC-like immunoreactivity was increased when treated with 1 nM BTC but was reduced after treatment with 100 nM of AG1478, an EGF receptor tyrosine kinase inhibitor. BTC has thus a significant growth stimulatory effect on pancreatic cancer cells and might function as an autocrine and paracrine growth factor. BTC expression in pancreatic cancer cells is, at least in part, controlled by an auto-induction mechanism.

Animals↗

In-flight cerebral oxygen status: continuous monitoring by near-infrared spectroscopy.

BACKGROUND: Little is known about the in-flight cerebral oxygen status (COS) of fighter pilots. The purpose of this study was to evaluate the COS of fighter pilots during an F-15DJ flight. METHODS: Three male F-15DJ fighter pilots volunteered to serve as test subjects during aerial gunnery training (AGT) missions. During the flight, the pilots' COS was continuously monitored from the right forehead using a NIRO-300G near-infrared spectrophotometer. This new instrument is capable of measuring the concentration changes in the brain of oxygenated hemoglobin (O2Hb), reduced hemoglobin (HHb), total hemoglobin (cHb, O2Hb + HHb), and the tissue oxygenation index (TOI, O2Hb/cHb). RESULTS: Continuous changes of COS within the brain were clearly demonstrated using NIRO-300G, the changes included reductions in O2Hb, cHb, and TOI with increased +Gz, in a mirror image fashion. The maximum decreased concentration of hemoglobin during flight ranged from 12.8 to 25.6 micromol x L(-1) (of brain tissue). CONCLUSIONS: We believe this study is the first monitoring of COS during F-15 actual flight. The monitoring of COS during F-15 flight showed that the effect of +Gz was to simultaneously lower blood flow in a mirror image fashion. Our results demonstrated that near-infrared spectroscopy (NIRO-300G) provides a reliable and sensitive method for the monitoring of pilots' COS during flight.

Acceleration↗

[Two cases of traumatic diaphragmatic hernia with atypical medical history].

We have recently experienced two cases of traumatic diaphragmatic hernia which has been repaired by surgery. The first case was a 58-year-old man who had suffered left upper abdominal injury with a branch in his childhood. Although he had never symptoms, chest X-ray showed abnormal shadow in the left lower lung field. Radiologic studies indicated that the great omentum was escaped into the thoracic cavity. On patient request, we performed primary repair of the diaphragmatic hernia on thoracotomy. The second case was a 56-year-old woman who had undergone a left nephrectomy for the left renal abscess. Seven months after the operation, she began to feel nausea and vomiting, and the symptom aggravated with time. Chest X-ray showed air bubbles in the left lower lung field. It proved to be a projection of the stomach into the thoracic cavity through the iatrogenic diaphragmatic injury. We successfully performed a repairment of the diaphragm with a mesh.

Female↗

A case of multiple myeloma which developed into multiple extramedullary involvement in the terminal stage.

A 69-year-old man with a diagnosis of multiple IgG class myeloma received combination chemotherapy. He achieved a partial response with an undetected M spike. However, he demonstrated new lytic bone lesions and multiple extramedullary involvement 10 months after the initial presentation. Polymerase chain reaction (PCR) analysis using a framework 3 (Fr3) V-region primer clarified a discrete band in the extramedullary tumor, while it yielded 4 bands including the same size as the extramedullary tumor produced in the bone marrow sample obtained before the chemotherapy. These findings suggest that a resistant and non-secretory clone was selected by the combination chemotherapy.

Aged↗

Genetic risk factors for coronary artery spasm: significance of endothelial nitric oxide synthase gene T-786-->C and missense Glu298Asp variants.

BACKGROUND: We recently identified two endothelial nitric oxide synthase (eNOS) gene polymorphisms, Glu298Asp and T-786-->C, which are independently associated with coronary spasm. eNOS gene intron 4b/a polymorphism is also reported to be involved in smoking-dependent coronary artery disease. The genetic linkage among these polymorphisms remains unknown. Also, it is unclear which variant is most responsible for coronary spasm. In the present study, we first examined the genetic linkage among these three variants. Next, we studied the risk factors of coronary spasm by using all significant genetic and conventional risk factors in a large-scale study. METHODS: The genotype and allele frequencies for the T-786-->C, intron 4b/a, and Glu298Asp variants were assessed in 423 randomly selected DNA samples to examine their genetic linkages. The relative capacities of all risk factors to predict coronary spasm were then analyzed using multiple logistic regression in 201 patients with coronary spasm and 345 volunteers. RESULTS: Comparison of allele frequencies revealed that the eNOS intron 4a allele was significantly linked to the T-786-->C mutation (P < 0.00001), whereas there was not a linkage between the intron 4a allele and the Glu298Asp variant (P = 0.1437) or between the Glu298Asp variant and the T-786-->C mutation (P = 0.1996). Multiple logistic regression revealed that the most predictive independent risk factor for coronary spasm was the T-786-->C mutation (P < 0.001), followed by cigarette smoking (P < 0.001), hypertension (P = 0.004), and the Glu298Asp variant (P = 0.028). CONCLUSIONS: We found that the T-786-->C mutation and the intron 4a allele are in linkage disequilibrium. We previously showed that the T-786-->C mutation reduced eNOS gene promoter activity. In that context, our results strongly suggest that the T-786-->C mutation underlies the functional characteristics of the intron 4a allele. Further, multiple logistic regression analysis revealed that the T-786-->C mutation is the most predictive risk factor for coronary spasm, followed by cigarette smoking. Given that those effects are potentially additive, patients carrying the eNOS gene variants should be strongly cautioned against smoking.

Adult↗

Expression of stromal cell-derived factor 1 and CXCR4 ligand receptor system in pancreatic cancer: a possible role for tumor progression.

To examine the expression of the stromal cell-derived factor 1 (SDF-1)/CXCR4 receptor ligand system in pancreatic cancer cells and endothelial cells, we performed immunohistochemical analysis for 52 pancreatic cancer tissue samples with anti-CXCR4 antibody and reverse transcription-PCR analysis for CXCR4 and SDF-1 in five pancreatic cancer cell lines (AsPC-1, BxPC-3, CFPAC-1, HPAC, and PANC-1), an endothelial cell line (HUVEC), and eight pancreatic cancer tissues. We then performed cell migration assay on AsPC-1 cells, HUVECs, and CFPAC-1 cells in the presence of SDF-1 or MRC-9 fibroblast cells. Immunoreactive CXCR4 was found mainly in pancreatic cancer cells and endothelial cells of relatively large vessels around a tumorous lesion. The immunopositive ratio in the pancreatic cancer was 71.2%. There was no statistically significant correlation with clinicopathological features. SDF-1 mRNA expressions were detected in all pancreatic cancer tissues but not in pancreatic cancer cell lines and HUVECs; meanwhile, CXCR4 mRNA was detected in all pancreatic cancer tissues, cancer cell lines, and HUVECs. The results indicate that the paracrine mechanism is involved in the SDF-1/CXCR4 receptor ligand system in pancreatic cancer. In vitro studies demonstrated that SDF-1 significantly increased the migration ability of AsPC-1 and HUVECs, and these effects were inhibited by CXCR4 antagonist T22, and that the coculture system with MRC-9 also increased the migration ability of CFPAC-1 cells, and this effect was significantly inhibited by T22. Our results suggested that the SDF-1/CXCR4 receptor ligand system may have a possible role in the pancreatic cancer progression through tumor cell migration and angiogenesis.

Adult↗