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T Sano

Publications and source records attributed to T Sano.

At least 325 records · Page 18Linked to original sources
PubMed1997

Impaired beta-cell function and deposition of fat droplets in the pancreas as a consequence of hypertriglyceridemia in OLETF rat, a model of spontaneous NIDDM.

Hypertriglyceridemia is known to be a feature of obesity-related NIDDM, but the patho-etiological significance of this association is obscure. The effects of triglycerides (TGs) on beta-cell function and morphological changes in pancreas were examined using in vivo and in vitro approaches in male OLETF rats at ages 6, 12, and 30 weeks, with their diabetes-resistant counterpart, LETO rats, as normal controls. The results showed that, in the fasting state, plasma TGs in OLETF rats were increased 2.5-fold at age 6 weeks, 3.3-fold at age 12 weeks, and 6.2-fold at age 30 weeks, compared with age-matched LETO rats. The TG content in islets from 12-week-old OLETF rats was significantly increased when compared with those from their age-matched counterparts, but this was not the case with the 6-week-old OLETF rats. Therefore, the islets from 6-week-old rats were cultured with either free fatty acids (FFAs; 1.0 mmol/l sodium oleate) or TG (5.0 mmol/l Intralipide) for 72 h. Several abnormalities in OLETF rats were evident, in contrast to the results from control LETO rats: 1) glucose-induced insulin secretion was more inhibited by either FFAs or TGs in the presence of 27.7 mmol/l glucose, a result associated, at least in part, with reduced glucokinase activity in the islets; 2) a marked elevation in TG content was found in the islets; and 3) the deposition of fat droplets in the enlarged islets, even in the beta-cells, was found by Oil Red O-insulin double staining at age 30 weeks. In conclusion, hypertriglyceridemia resulted in significant TG stores in the islets, which subsequently inhibited glucose-induced insulin secretion, at least in part, via reduced glucokinase activity in the islets. Fat droplets in islets, therefore, may play an important role in hastening the development of NIDDM in this rat model.

Animals↗
PubMed1997

Occurrence of dermatitis in rats fed a cholesterol diet containing field horsetail (Equisetum arvense L.).

The effects of dietary field horsetail (Equisetum arvense L.) powder on lipid components were studied in rats fed a 20% casein diet with or without cholesterol (0.5% cholesterol and 0.15% sodium cholate) for 14 days. The ingestion of 0.4% or 4% Equisetum arvense L. powder did not influence food intake or growth. However, a cholesterol diet with Equisetum arvense L. at 4% caused dermatitis at the neck, head and back in about 20-65% of the rats. This dermatitis was reversed when the diet was changed to commercial pellets. There were no apparent effects on serum or liver lipids in the rats fed Equisetum arvense L. irrespective of dietary cholesterol. Serum IgE levels measured by enzyme-linked immunoassay revealed that the induction of IgE may not necessarily be involved in the dermatitis caused by the intake of Equisetum arvense L. These results suggest that the ingestion of large amounts of Equisetum arvense L. as cooking material is not recommended for those with a cholesterol-rich diet.

Animals↗
PubMed1997

CD34 expression by inflammatory fibroid polyps of the stomach.

The phenotype of the proliferated spindled cells and the histogenesis of inflammatory fibroid polyp (IFP) have been a matter of debate. To clarify the immunohistochemical profile of the main cellular component, we reviewed histologically and studied immunohistochemically 11 cases (12 lesions) of IFP of the stomach. The lesions ranged in size from 0.4 to 3.0 cm (mean, 1.0 cm). All of the IFPs occurred in the antrum. Seven cases (63.6%) were accompanied by carcinoma or adenoma, which in two cases was present in covering epithelium. Grossly, eight IFPs were sessile, and four were polypoid. Microscopically, seven (58.3%) occupied both the mucosa and submucosa. Four (33.3%) were confined to the mucosa, and one was localized only in the submucosa. They were characterized by proliferation of relatively uniform spindled cells, often in a whorl-like arrangement around the blood vessels and glands. Eosinophilic and lymphocytic infiltration of varying degree was always present. The spindled cells in all of the IFPs were diffusely immunoreactive for vimentin and CD34. Seven (58.3%) were focally positive for histiocytic markers, such as KP1 and HAM56. Three (25%) showed focal immunoreactivity for alpha smooth muscle actin. Cytokeratin, desmin, S100 protein, Factor VIII RAG, and Ki-67 were negative in these spindled cells. The principle proliferating cells in IFPs in this study showed variable degrees of histiocytic and myofibroblastic lines of differentiation. Under the influence of some etiologic factors, the primitive, uncommitted spindled mesenchymal cells exhibiting CD34 immunoreactivity around the blood vessels and glands in the lower portion of mucosa and submucosa might play a role in development of IFP.

Actins↗
PubMed1997

Amylase concentration of drainage fluid after total gastrectomy.

BACKGROUND: Pancreatic fistula is a serious complication of total gastrectomy with splenectomy. The amylase content of drainage fluid was examined and its usefulness for predicting pancreatic complications after gastrectomy was evaluated. METHODS: The amylase concentration of the fluid in the peripancreatic drain was determined prospectively in 102 patients who underwent total gastrectomy in 1995. RESULTS: Pancreatic fistula developed in 13 patients, whose drainage fluid amylase levels on the first postoperative morning were significantly higher than those of patients without fistula formation. Among 27 patients with amylase levels exceeding 4000 units, eight later developed pancreatic fistula, while only five (7 per cent) of 68 with amylase levels below 4000 units did so. All complications were successfully managed and there were no deaths. CONCLUSION: Determination of drainage fluid amylase levels is a simple and useful method for the prediction of pancreatic fistula formation and may help to plan appropriate management.

Adult↗
PubMed1997

Giant plexiform schwannoma: a report of two cases with soft tissue and visceral involvement.

We report two cases of massive, solitary, plexiform schwannoma. One was a 9-cm subcutaneous lesion on the hip of a 72-year-old man who had become aware of the slow-growing tumor 50 years earlier; the other is the first reported plexiform schwannoma to arise in a visceral organ: it arose in the ascending colon of a 54-year-old man and exhibited a dumbbell configuration with submucosal and subserosal components. Neither patient had neurofibromatosis or schwannomatosis. Both tumors were well-circumscribed and multinodular, and both showed a plexiform architecture. Microscopically, the nodules were composed primarily of Antoni A tissue, replete with nuclear palisading and Verocay bodies. Examination by immunohistochemistry and electron microscopy demonstrated the features of well-differentiated Schwann cells; nodules were surrounded by attenuated, residual perineurium. Both patients followed a benign clinical course, without recurrence or metastasis. Neither the large tumor size nor the unusual locations affected the biologic behavior of these neoplasms. A massive plexiform schwannoma must be distinguished from a malignant peripheral nerve sheath tumor and from a plexiform neurofibroma, a tumor prone to malignant transformation.

Aged↗
PubMed1996

A phase I and II clinical trial of a newly developed ultrasound hyperthermia system with an improved planar transducer.

PURPOSE: The clinical usefulness of a newly developed ultrasound hyperthermia system was evaluated. METHODS AND MATERIALS: The hyperthermia system uses a modified planer transducer operated at frequencies of 0.5, 1.0, and 1.5 MHz. The transducer has a nonvibrating part at the center to reduce the central hot spot. Frequency sweeping technique is also used to eliminate the annular hot spot around the center. Thirty-eight tumors in 29 patients were examined in this study. In 35 tumors, hyperthermia was given in conjunction with irradiation and/or chemotherapy, and in the remaining 3 tumors, hyperthermia alone was given. In all, a total of 153 hyperthermia sessions were performed. RESULTS: The number of hyperthermia sessions per tumor ranged from 1 to 7 (mean, 4.0 +/- 1.3). The number of intratumor thermometry points per session ranged from 1 to 8 (mean, 4.3 +/- 1.5). The average intratumor temperature for tumors with a maximum depth of <3 cm, 3-6 cm, and >6 cm was 42.1 +/- 1.2, 41.7 +/- 1.4, and 39.9 +/- 2.0 degrees C, respectively. The percentage of monitored intratumor points with temperature exceeding 42 degrees C was 56 +/- 31%, 43 +/- 34%, and 21 +/- 24%, respectively. Of the 30 evaluable tumors treated with combined irradiation, 12 showed complete response, 14 partial response, and 4 no change. Observed complications included pain at the treatment site in 13 of the 153 treatment sessions and vesicle formation in 3 of the 38 treatment sites. No serious complication was seen. CONCLUSIONS: These results indicate that the newly developed ultrasound hyperthermia system is clinically useful for the treatment of localized superficial and subsurface tumors with a maximum tumor depth of no more than 6 cm.

Adult↗
PubMed1996

Prevention of adoptively transferred diabetes in nonobese diabetic mice with IL-10-transduced islet-specific Th1 lymphocytes. A gene therapy model for autoimmune diabetes.

Four pancreatic islet-specific CD4+ helper T (Th) 1 (Th1) clones and two Th1 clones transduced with an SRalpha promoter-linked murine IL-10 (mIL-10) cDNA of 2.0-6.0 x 10(6) cells were adoptively transferred to nonobese diabetic (NOD) mice at age 8 d. Cyclophosphamide (CY) was administered at age 37 d (plus CY), and the incidence of diabetes and the histological grade of insulitis were examined at age 47 d. After the adoptive transfer of IL-10-transduced Th1 cells, polymerase chain reaction (PCR) and reverse-transcription (RT)-PCR detected the neo gene and the retrovirus vector-mediated IL-10 mRNA in situ in recipient islets, respectively. RT-PCR detected the decrease of IFN-gamma mRNA relative to IL-10 mRNA in IL-10-transduced Th1 clones in vitro and also in recipient islets. All four wild type Th1 clones plus CY induced the insulitis grade of 2.75 and diabetes in 66% of recipient NOD mice. IL-10-transduced two Th1 clones plus CY induced periinsulitis with the grade of 1.43 and diabetes in 8.0%. The 1:1 mixture of wild type Th1 cells and IL-10-transduced Th1 cells plus CY induced periinsulitis with the grade of 1.85 and diabetes in 20%. The suppression of diabetes through decreasing IFN-gamma mRNA by the tissue-specific delivery of IL-10 to pancreatic islets with IL-10-transduced Th1 cells affords us the starting basis to develop the gene therapy for autoimmune diabetes.

Adoptive Transfer↗
PubMed1996

Induction and its spread of apoptosis in rat spinal cord after mechanical trauma.

This study was undertaken to examine the spinal cord of rats after trauma for the induction of apoptosis. DNA ladder formation was demonstrated by gel electrophoresis of the DNA obtained from the spinal cord at the site of injury after trauma from 12 h to 8 days and was most significant on Days 3 and 4. As for the longitudinal spread of the injury in the spinal cord, the ladder formation was observed in the two segments adjacent to the site of trauma 3 days after trauma. Histological examination using in situ end labeling also demonstrated the appearance of apoptosis. These results provide the evidence for the induction of apoptosis in the spinal cord after trauma in rats.

Animals↗
PubMed1996

Risk factors for lymph node metastasis from intramucosal gastric carcinoma.

BACKGROUND: Although regional lymph node metastasis from intramucosal early gastric carcinoma (EGC) is rare, it is very important to clarify the characteristics of patients having lymph nodal metastases in order to determine appropriate therapy. METHODS: The authors investigated 1196 patients with solitary intramucosal EGC who underwent resection at the National Cancer Center Hospital in Tokyo, with special reference to lymph node metastases. Eight clinicopathologic factors (age, sex, tumor: size, location, macroscopic type, histologic type, histologic ulceration of the tumor, and lymphatic vessel invasion) were investigated by univariate and multivariate analyses for their possible relationship to lymph node metastasis. RESULTS: Lymph node metastases were found in 43 patients (3.5%). Univariate analysis revealed that younger age (< 57 years), macroscopic depressed type, larger tumor size (> or= 30 mm), undifferentiated histologic type, histologic ulceration of the carcinoma, and lymphatic vessel invasion had a significant association with regional lymph node metastasis. Multivariate analysis revealed that lymphatic vessel invasion, histologic ulceration of the tumor, and larger size (> or = 30 mm) were independent risk factors for regional lymph node metastasis. The incidence of lymph node metastasis from intramucosal EGC negative for these 3 risk factors was only 0.36% (1 in 277 patients). CONCLUSIONS: Lymphadenectomy is unnecessary for patients with small intramucosal EGC with neither histologic ulceration of the tumor nor lymphatic vessel invasion because the incidence of regional lymph node metastasis is extremely low in those patients. The therapeutic options for such patients would be local resection or endoscopic resection.

Age Factors↗
PubMed1996

Effects of long-term enalapril treatment on persistent microalbuminuria in normotensive type 2 diabetic patients: results of a 4-year, prospective, randomized study.

The beneficial effect of long-term treatment with an angiotensin-converting enzyme (ACE) inhibitor on urinary microalbumin excretion (UAE) and renal function was investigated in a 4 year, randomized prospective study in normotensive patients with non-insulin-dependent (Type 2) diabetes mellitus. Sixty-two normotensive patients with Type 2 diabetes mellitus and microalbuminuria but normal renal function were randomized to receive either enalapril 5 mg day-1 or no treatment. In the enalapril-treated patients, UAE was reduced from 115.4 +/- 80.1 to 95.6 +/- 61.7 mg 24 h-1 after 12 months (p < 0.05) and to 75.3 +/- 44.8 mg 24 h-1 after 48 months (p < 0.001). In the untreated group, UAE increased slowly from 93.9 +/- 69.9 to 150.0 +/- 144.5 mg 24 h-1 after 48 months. No changes in creatinine clearance, blood pressure or HbA1C were seen in either group during the 4-year period. In normotensive Type 2 diabetic patients with early stage of diabetic microalbuminuria. This effect is long-lasting and probably independent of the antihypertensive action of the drug.

Aged↗
PubMed1996

Platelet kinetics after transfusion.

A kinetics model is proposed for platelet disposition after transfusion of platelets. In this model, transfusion of platelets and production of endogenous platelets contribute to an increase in the number of platelets in patients, and the life span and age of each platelet contribute to a decrease. The time course of the number of platelets after transfusion of platelets is theoretically described by this model to be a straight line followed by a concave curve. When the platelets have a life span without any variation, a linear pattern is observed in spite of their different ages at the transfusion. This model with a constant life span was applied to three patients receiving platelet transfusion, and the model parameters were calculated by curve fitting the observed platelet levels to the model using the nonlinear least-squares method. As a result, the life span, distribution volume per body weight, and endogenous platelet level (averages for three patients) were calculated as 6.29 d, 0.137 L kg-1, and 1.40 x 10(4) counts microL-1, respectively. The calculated platelet levels in individual patients were compared with the observed ones during the next transfusions, and the relative and absolute differences between calculated and observed values were 2.0 +/- 15.3% and -0.075 +/- 0.443 x 10(4) counts microL-1 (mean +/- SD, 15 observed points for three patients), respectively. These case studies suggest that the model could be clinically useful for individual platelet transfusion.

Adult↗
PubMed1996

Ectopic adrenocorticotropin syndrome associated with undifferentiated carcinoma of the colon showing multidirectional neuroendocrine, exocrine, and squamous differentiation.

We report a rare case of ectopic ACTH syndrome associated with undifferentiated carcinoma of the ascending colon. A 62-year-old woman developed hypokalaemia and metabolic alkalosis associated with markedly elevated serum cortisol and plasma ACTH levels. High-dose dexamethasone (8 mg/day) did not suppress increased urinary 17-hydroxycorticosteroid and 17-keto-steroid excretion. Barium enema and abdominal computerised tomography showed a Borrmann II type tumour in the ascending colon, multiple metastatic nodules in the liver and bilateral enlargement of the adrenal glands. Histological examination of the resected primary colon cancer and metastatic liver tumour showed undifferentiated carcinoma with areas of distinct neuroendocrine, exocrine, and squamous differentiation. ACTH production by the tumour was confirmed by radioimmunoassay and immunohistochemistry. This is a unique case report of carcinoma of the colon with distinct multidirectional differentiation causing ectopic ACTH syndrome.

ACTH Syndrome, Ectopic↗
PubMed1996

Two cases of lymphocytic hypophysitis presenting with diabetes insipidus: a variant of lymphocytic infundibulo-neurohypophysitis.

BACKGROUND: It has been thought that neurohypophysial involvement manifesting as central diabetes insipidus in lymphocytic hypophysitis is uncommon. Although cases with such an association have been reported recently with increasing frequency, the relationship with lymphocytic infundibular neurohypophysitis remains unclear. METHODS AND RESULTS: Two postmenopausal women who presented with diabetes insipidus are reported. Adenohypophysial function was normal in both cases, apart from growth hormone secretion. Magnetic resonance imaging revealed a sellar mass lesion mimicking pituitary adenoma, with loss of the hyperintense signal of the neurohypophysis in both cases and thickening of the stalk in one case. The lesion was located behind the residual adenohypophysis during transsphenoidal biopsy; however, histologic examination showed chronic inflammation of the adenohypophysis, findings identical to those of lymphocytic adenohypophysitis. Although the principal site of the inflammation was considered to be the neurohypophysial system, adenohypophysis was also involved in the lesion. We suggest that these cases represent a variant of lymphocytic infundibular neurohypophysitis. CONCLUSION: To avoid unnecessary surgical intervention, it is important to note that some variants of lymphocytic infundibulo-neurohypophysitis may form a mass lesion not localized in the neurohypophysial system but involving the adenohypophysis, thus resembling adenomas and other tumors.

Diabetes Insipidus↗