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M Sato

Publications and source records attributed to M Sato.

At least 559 records · Page 31Linked to original sources
PubMed2000

Long-term follow-up of obstructive sleep apnea syndrome following surgery in children and adults.

Obstructive sleep apnea syndrome (OSAS) is characterized by recurrent apneas during sleep, resulting in repetitive hypoxemia. The present study retrospectively analyzed subjective and objective assessments of the patients with OSAS in a relatively long-term follow-up. From February 1986 to August 1996, 53 patients received surgical treatment for OSAS and snoring. Thirty-seven (27 males and 10 females) out of 53 patients completed the questionnaire and postoperative sleep study was obtained in 6 patients. In 20 children (<15 years), snoring, sleep apnea, and daytime sleepiness completely disappeared in 12, 19, and 16, and improved in 8, 1, and 4, respectively. These findings confirm that tonsillectomy and/or adenoidectomy in children may be the first selection for treatment. In 17 adults, snoring, sleep apnea, and daytime sleepiness completely disappeared in 2, 5, and 8, improved in 11, 8, and 7, and was unchanged in 4, 4, and 1, respectively. The apnea index in adults was significantly decreased in both early and late postoperative periods. These results suggest that surgery is a satisfactory alternative for adult patients if performed accurate preoperative diagnosis of the localization of the airway collapse and careful long-term follow-up.

Adenoidectomy↗
PubMed2000

Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats 13). Effects of a single oral dose of cyclophosphamide.

As part of a collaborative effort to evaluate whether effects on male reproductive organs of chemicals can be detected within two-week in toxicity studies, eight-week-old male Sprague-Dawley rats were given a single oral administration of 100 mg/kg of Cyclophosphamide (Cp), and sacrificed at 1, 3, 7 and 14 days thereafter. The numbers of seminiferous epithelial cells were counted in the seminiferous tubules of stages II-III, V, VII and XII of the spermatogenic cycle. Animals showed decreased spermatogonia at Day 3, decreased spermatogonia and preleptotene spermatocytes at Day 7, and decreased spermatogonia and zygotene spermatocytes at Day 14. We also detected decrease of zygotene spermatocytes on careful routine/traditional histopathological examination at Day 14. These results suggest that the testicular toxicity of Cp can be detected within two weeks after treatment with a sufficient dose in rats.

Administration, Oral↗
PubMed2000

Radiation-induced diffuse brain injury in the neonatal rat model--radiation-induced apoptosis of oligodendrocytes.

The mechanism of radiation-induced diffuse brain injury was investigated using a model of delayed myelination in the irradiated neonatal rat brain in which the number of oligodendrocytes decreases without associated necrosis of the cerebral white matter. Immunohistochemical analysis using antibody against the large myelin-associated glycoprotein, a specific marker of oligodendrocytes at an early stage of development, showed that the number of the oligodendrocytes associated with myelination decreased in the irradiated hemisphere 1 day after irradiation and remained low until 5 days after irradiation. In situ terminal deoxynucleotidyl transferase-mediated nick end-labeling assay revealed that apoptosis mainly occurred in the cerebral white matter of the irradiated hemisphere. Three hours after irradiation, apoptotic cells were found in the subcortical white matter and the periventricular white matter. Six hours after irradiation, apoptotic cells were found in the internal capsule, and the numbers of apoptotic cells in the periventricular white matter and subcortical white matter increased. One day after irradiation, the number of apoptotic cells in the periventricular white matter decreased. Three days after irradiation, apoptotic cells were not observed in the cerebral white matter. These results suggest that the oligodendrocytes associated with myelination may be damaged via radiation-induced apoptosis, and depletion of the oligodendrocytes may cause delay of myelination.

Animals↗
PubMed2000

Comparison of CT findings with resected specimens after chemoembolization with iodized oil for hepatocellular carcinoma.

OBJECTIVE: We assessed the role of dynamic CT in the evaluation of the efficacy of transarterial chemoembolization with iodized oil for hepatocellular carcinoma. MATERIALS AND METHODS: We examined 41 hepatocellular carcinoma lesions (mean diameter, 5.0 cm) in 40 patients (mean age, 60.6 years) who underwent transarterial injection of iodized oil alone (n = 3) or emulsion of iodized oil and doxorubicin hydrochloride (n = 10) followed by gelatin sponge particles (n = 27) and subsequent hepatectomy. On dynamic CT performed within 3 weeks before oily transarterial chemoembolization and within 4 weeks before surgery, we calculated the rate of necrosis on the basis of the assumption that the portion that retained iodized oil represented necrosis. We also calculated the reduction rate of the tumor. CT findings were compared with pathologic findings of resected specimens. RESULTS: Pathologic specimens and the necrosis rate measured on CT showed a good correlation (r = 0.83) when the portion of tumor that retained iodized oil was considered necrosis. No correlation existed if the portion that retained iodized oil was considered viable. We noted no significant correlation (r = 0.38) between the reduction rate of the tumor and necrosis rate. Also, we noted no correlation (r = 0.52) between the interval between transarterial oily chemoembolization and surgery and the reduction rate of the tumor. CONCLUSION: CT is suitable for the evaluation of the efficacy of oily chemoembolization for hepatocellular carcinoma on the basis of the assumption that the portion of tumor that retains iodized oil is necrotic. The rate of tumor size reduction measured on CT did not correlate with the therapeutic effect of chemoembolization.

Aged↗
PubMed2000

Effects of saiko-ka-ryukotsu-borei-to on spontaneous locomotor activity in mice. Oriental Medicine Research Group.

The effects of the Japanese Kampo (herbal) medicine, Saiko-ka-ryukotsu-borei-to, on spontaneous locomotor activity were studied in mice. Saiko-ka-ryukotsu-borei-to (60 mg, 150 mg and 300 mg/kg/day) was administered for 14 consecutive days in the drinking water and spontaneous locomotor activity was measured for 60 min by a photocell ambulometer. Saiko-ka-ryukotsu-borei-to (60 mg/kg/day) significantly increased the total activity count on the 11th day after the start of administration when compared to vehicle control, whereas failed to significantly affect the activity on the 2nd, 5th, 8th and 14th days. A similar significant increase was also found with a higher dose (150 mg/kg/day) on the 8th day after the start of administration. However, the highest dose (300 mg/kg/day) did not significantly affect locomotor activity throughout the experimental period. We have previously reported that Saiko-ka-ryukotsu-borei-to, at a dose of 60 mg/kg/day, enhances escape attempts assessed by water-wheel rotations in a mouse model of despair, particularly on the 8th, 11th and 14th days after the start of chronic treatment. However, at higher doses (150 and 300 mg/kg/day), Saiko-ka-ryukotsu-borei-to decreases the escaped attempts on the 5th and 8th days after the treatment. It is therefore concluded that the previously reported changes in escape attempts of mice are not associated with the changes in their spontaneous locomotor activity.

Administration, Oral↗
PubMed2000

Gamma knife radiosurgery as a primary treatment for prolactinomas.

OBJECT: The purpose of this study was to estimate the efficacy of gamma knife radiosurgery (GKS) in controlling tumor growth and endocrinopathy associated with prolactinomas. METHODS: Between 1993 and 1997, 164 of 469 patients with pituitary adenomas treated by GKS harbored prolactinomas. The dose to the tumor margin ranged from 9 to 35 Gy (mean 31.2 Gy), and the visual pathways were exposed to a dose of less than 10 Gy. The mean tumor diameter was 13.4 mm. The mean follow-up time for 128 cases was 33.2 months (range 6-72 months). Tumor control was observed in all but two patients who underwent surgery 18 and 36 months, respectively, after GKS. Clinical cure was achieved in 67 cases. Clinical improvement was noted with a decrease in the hyperprolactinemia after GKS. Nonetheless, in 31 (29%) of 108 patients who were followed for more than 2 years no improvement in serum prolactin levels was demonstrated, although this could be normalized by bromocriptine administration after treatment. Nine infertile women became pregnant 2 to 13 months after GKS and all gave birth to normal children. There was no visual deterioration related to GKS. Five women experienced premature menopause. In these patients there was subtotal disappearance of the tumor and an empty sella developed. CONCLUSIONS: Gamma knife radiosurgery as a primary treatment for prolactinomas can be safe and effective both for controlling tumor growth and for normalization of prolactin hypersecretion. A higher margin dose (> or = 30 Gy) seemed to be associated with a better clinical outcome. Gamma knife radiosurgery may make prolactinomas more sensitive to the bromocriptine.

Humans↗
PubMed2000

Suppression of glycogen consumption during acute exercise by dietary branched-chain amino acids in rats.

The effects of a diet supplemented with branched-chain amino acids (BCAA; 4.8% or 6.2%) on BCAA catabolism and glycogen metabolism in rats were examined. Rats were fed a BCAA diet or control diet for 4 wk and part of the rats were subjected to exercise training during the experimental period. Feeding the BCAA diet increased serum BCAA concentrations and activity of the hepatic branched-chain alpha-keto acid dehydrogenase complex, the rate-limiting enzyme in the catabolism of BCAA, suggesting that dietary BCAA promotes BCAA catabolism. Although the serum glucose concentration and glycogen contents in the liver and gastrocnemius muscle of rested rats were not significantly affected by feeding of the BCAA diet, those in rats exhausted by acute exercise were 2-4-fold higher in rats fed the BCAA diet than in rats fed the control diet. The activity of pyruvate dehydrogenase complex in the liver and gastrocnemius muscle after acute exercise showed reverse trends; the complex activities (especially in liver) tended to be less in the BCAA diet group than in the control diet group. These results suggest that dietary BCAA spares glycogen stores in liver and skeletal muscle during exercise and that the decrease in pyruvate dehydrogenase complex activity in these tissues by dietary BCAA is involved in the mechanisms.

Amino Acids, Branched-Chain↗
PubMed2000

Tissue engineering in the twenty-first century.

In the 20th century, free tissue transfers have been successfully introduced using microvascular anastomosis techniques. Transplants not only include whole organs such as the kidney, liver and lung, but also bone, muscle and skin. However, there are a limited number of organs available for transplantation. This leads to the patient not only suffering from the malfunctioning tissue or organ, but also from the psychological trauma of an indefinite waiting period. The rapidly evolving field of tissue engineering is beginning to have an impact on free tissue transfers including organ. Small biopsy specimens can be grown into a large number of cells. These cultured cells can then be seeded onto biodegradable polymers, which serve several purposes. Firstly, the polymers function as a cell delivery system that enables the transplantation of a large numbers of cells into an organism. Secondly, they create a three-dimensional space for cell growth and serve as a template, thereby providing a structure for the extracellular matrix. These approaches have been demonstrated as practical strategies for the reconstruction of many tissues such as the liver, intestines, heart valve leaflets, bone and cartilage.

Animals↗
PubMed2000

Antitumor activity of alpha-galactosylceramide, KRN7000, in mice with the melanoma B16 hepatic metastasis and immunohistological study of tumor infiltrating cells.

Liver metastasis of primary tumors is clinically a major problem. We examined the antitumor activity of KRN7000, an alpha-galactosylceramide, in mice with liver metastasis of the B16 melanoma. KRN7000 significantly inhibited tumor growth in the liver, and its potency was similar to that of interleukin-12. The KRN7000 administration resulted in a high percentage of cured mice, which acquired tumor-specific immunity. To study what kinds of antitumor effector cells participated in killing tumor cells, we then performed immunohistological analysis of tumor-infiltrating cells, and found that KRN7000 induced marked invasion of NK1.1+ cells, CD8+ cells, and F4/80+ cells (macrophages) into B16 tumor nodules. In addition, it appeared that KRN7000-treated, liver-associated macrophages possessed strong lytic activity against tumor cells. These results suggest that NK cells, NK1.1+ T (NKT) cells, cytotoxic T lymphocytes, and macrophages play an important role in killing tumor cells in the liver, and that KRN7000 may be useful for the treatment of cancer liver metastasis.

Animals↗
PubMed2000

MDM2 expression is associated with progress of disease and WAF1 expression in resected lung cancer.

Although MDM2, p21/WAF1, and p53 are considered as regulating each other based on in vitro studies, the relation in human lung cancer is not fully understood. The expressions of these proteins were examined immunohistochemically in 112 resected non-small cell lung cancer specimens and the correlation between them were analyzed. MDM2 was expressed in 45% of all lung cancers. In advanced stage, MDM2-positive cases were observed more frequently than in early stage, showing significant difference. No significant difference was observed in the prognosis of the patients regardless of the expression of any protein. Although no correlation was observed between MDM2 expression and p53 expression, or between p21/WAF1 expression and p53 expression, MDM2 expression was strongly related with p21/WAF1 expression. Therefore, MDM2 expression may relate to the progress of the stage of lung cancer, and MDM2 expression and p21/WAF1 expression may be associated not through the p53-related pathway.

Adenocarcinoma↗
PubMed2000

Cell mechanics.

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Biomechanical Phenomena↗
PubMed2000

Sex-related differences in urinary excretion of egualen sodium in rats.

Egualen sodium (sodium 3-ethyl-7-isopropyl-1-azulenesulfonate 1/3 hydrate) is a new antiulcer drug. There has been no difference observed in absorption between male and female rats, the relative amount of metabolites in male plasma has been higher than that in females, and the excretion ratios of metabolites in males have been significantly higher than those in females. However, the plasma concentration profile of total radioactivity in males has been higher than that in females. To clarify this discrepancy, the renal clearances and plasma concentrations of the unchanged drug and its metabolites were determined. The renal clearance of the unchanged drug in males was 21 times lower than that in females, and the urinary excretions in males and females were 2.1 and 39.5% of dose, respectively. This indicates that the major factor in the sex-related difference observed in the plasma concentration of total radioactivity is due to the difference in the renal clearance of the unchanged drug between the sexes. The results of treatments with probenecid in normal and gonadectomized rats revealed that egualen sodium was mainly excreted into urine by secretion through the renal tubule. Furthermore, the results of treatments with testosterone in rats revealed that the excretion of egualen sodium was highly affected by androgens. These facts indicated that the sex-related difference observed in the plasma concentration of total radioactivity can be attributed to the inhibition of renal tubular secretion of the unchanged drug by androgens. This is the first example of sex-related differences in both metabolism and excretion.

Administration, Oral↗
PubMed2000

Analysis of hepatocellular carcinoma fed by internal thoracic artery

Purpose: The purpose of this study was to elucidate the clinical features of hepatocellular carcinoma (HCC) fed by the internal thoracic artery (ITA). Methods: In seven patients HCC fed by the ITA was confirmed by digital subtraction angiography. The number of previous transcatheter arterial embolization (TAE), the period from the first TAE to TAE of the ITA, tumor location, tumor size, and occlusion of the hepatic artery (HA) and other collateral vessels were explored in each case. Results: The HCCs were located in S4 of the liver (n = 5) and in S8 (n = 1) and were fed by the right ITA and one nodule in S2-3 was fed by the left ITA. Tumor size was 3-10 cm. The number of previous TAE of the HA ranged from 2 to 12. The period from the first TAE to TAE of the ITA was 3-53 months. Angiography of these patients showed occlusion of the HA in six cases, and of the extrahepatic collaterals including the inferior phrenic artery (IPA) in five cases, intercostal artery (ICA) in one case, and epicholedocal artery (EPA) in one case. Conclusion: The ITA often supplies HCC located in the anterior superior region of the liver under the diaphragm; there can be long-term survival with repeated TAE and occlusion of HA.

Journal Article↗
PubMed2000

[Adenocarcinoma of the ileal segment with transitional cell carcinoma of the bladder following ileocytoplasty: a case report].

A 67 year-old woman visited our hospital complaining of pollakisuria. She had undergone left nephrectomy and augmentation ileocystoplasty for tuberculous bladder atrophy 40 years previously. She underwent a total cystectomy and tubeless ureterocutaneostomy with a preoperative diagnosis of muscle-invading transitional cell carcinoma of the bladder. The pathological diagnosis was adenocarcinoma of the ileal segment and transitional cell carcinoma of the original bladder. This is the first case report of adenocarcinoma of the ileal segment and transitional cell carcinoma of the original bladder among 22 patients suffering from bladder cancer after ileocystoplasty.

Adenocarcinoma↗
PubMed2000

Uptakes and images of 38K in rabbit heart, kidney, and brain.

UNLABELLED: The purpose of this study was to evaluate the kinetics and image quality of positron-emitting 38K (half-life, 7.6 min) and high-resolution small-animal PET in the heart, kidney, and brain of rabbits. METHODS: Studies were performed with 18 closed-chest anesthetized rabbits at baseline and during infusions of adenosine (0.2 mg/kg/min) and propranolol (0.5-1.0 mg/kg intravenously) using high-resolution small-animal PET. 38K was injected intravenously and dynamic PET imaging of the heart, kidney, or brain was performed for 3 min. Colored microspheres were injected into the left ventricle to measure organ blood flow. Arterial blood was withdrawn directly from the femoral artery, and, after the animals were killed, 38K activities in each organ were measured directly with a well counter. Uptake of 38K was calculated by dividing the 38K activities in each organ by the integral of the input function. The extraction fraction of 38K was estimated by dividing the uptake of 38K in each organ by the organ blood flow, measured by microspheres. RESULTS: The left ventricular myocardium and kidney were clearly visualized, but there was no visual 38K uptake in the brain. For the heart, kidney, and brain, respectively, average blood flow was 2.91 +/- 1.29, 5.49 +/- 0.71, and 0.57 +/- 0.11 mL/min/g, and the extraction fraction of 38K at baseline was 0.55 +/- 0.13, 0.48 +/- 0.13, and 0.022 +/- 0004. The Renkin-Crone model fit the relation between myocardial extraction and flow under a wide range of myocardial blood flow (r = 0.89). CONCLUSION: 38K is a suitable tracer for noninvasively showing the potassium kinetics of the heart, kidney, and brain by PET imaging.

Animals↗
PubMed2000

[Expression of reactive oxygen-species related enzymes in endothelial cells stimulated with glycated lipoproteins].

Glycated lipoproteins, which elevate the blood in diabetic patients, cause direct attenuation of endothelial function. Increased glycation of apolipoproteins may play a trigger role in the accelerated development of atherosclerosis in the patient with diabetes. Here we assessed whether glycated lipoproteins affect on the endothelial function with particular emphasis on the role of reactive oxygen species in vitro. Incubation of human aortic endothelial cells(HAEC) with glycated LDL had little influence on the expression of antioxidant enzymes such as nitric oxide synthase(NOS), Cu2+Zn(2+)-superoxide dismutase (Cu2+Zn(2+)-SOD), catalase, and p22 phox in the cells. In contrast, exposure of glycated HDL induced a marked decrease of Cu2+Zn(2+)-SOD, catalase, and endothelial NOS as well as a slight increase of p22 phox in HAEC in term of both protein and mRNA expression, suggesting that increased formation of reactive oxygen species such as O2- and OH radical participate in the deterioration for the function of vascular endothelial cells in diabetic patients.

Arteriosclerosis↗