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S Takase

Publications and source records attributed to S Takase.

At least 127 records · Page 7Linked to original sources
PubMed1995

Dietary regulation of sucrase-isomaltase gene expression in rat jejunum.

We have previously demonstrated that intake of fat as well as carbohydrate affects the activity and immunoreactive amount of sucrase-isomaltase (S-I) in rat jejunum. To examine whether diet-related changes in sucrase and isomaltase activities are accompanied by the variations of sucrase-isomaltase mRNA levels, 7-week-old rats were fed either a high-long-chain triacylglycerols diet (73 energy% as corn oil), a high-medium-chain triacylglycerols (MCT) diet (66 energy% as MCT, 7 energy% as corn oil) or a high-carbohydrate diet (70 energy% as corn starch) for 7 days. Northern blot analysis revealed that S-I mRNA levels were abundant in the jejunum of rats fed the high-MCT diet; the levels were similar to those in the rats fed the high-carbohydrate diet. Force-feeding a high-sucrose diet (40 energy% as sucrose) brought about a parallel rise in both S-I mRNA and sodium/D-glucose cotransporter (SGLT1) mRNA levels within 12 h. Force-feeding the high-MCT diet also produced an elevation of S-I mRNA and SGLT1 mRNA. However, force-feeding a diet containing alpha-methylglucoside, a non-metabolizable but actively transported sugar, did not increase S-I mRNA or SGLT1 mRNA level; sucrase activity was nevertheless elevated by feeding alpha-methylglucoside diet. These results suggest that not only carbohydrate intake but also MCT intake might influence S-I mRNA and SGLT1 mRNA levels in the jejunum, presumably through common metabolite(s) of carbohydrates and MCT, and that carbohydrate may play another role in enhancement of the sucrase activity through modulation of translation and/or posttranslational modifications of the sucrase-isomaltase complex.

Animals↗
PubMed1995

Tau in cerebrospinal fluid: a potential diagnostic marker in Alzheimer's disease.

Cerebrospinal fluid from 70 patients with Alzheimer's disease (AD) and 96 patients with non-AD neurological diseases as well as 19 normal control subjects was surveyed by sandwich enzyme-linked immunosorbent assay to quantitate levels of the microtubule-associated protein tau in cerebrospinal fluid. The tau level was significantly increased in AD patients as compared with that in patients with non-AD neurological diseases and control subjects. Increased tau levels were found irrespective of age at onset, apolipoprotein E genotype, and clinical stage. Western blots of AD cerebrospinal fluid proteins revealed two to three tau-immunoreactive bands with an apparent molecular mass between 50 and 65 kd consistent with phosphorylated cerebrospinal fluid tau. Taken together, our results suggest that cerebrospinal fluid tau might reflect the progressive accumulation of altered tau due to the progressive death of neurons in the AD brain, and that the enzyme-linked immunosorbent assay of cerebrospinal fluid tau may prove to be a reliable and early diagnostic test for AD.

Adult↗
PubMed1995

Dietary maltitol increases calcium content and breaking force of femoral bone in ovariectomized rats.

Maltitol is a disaccharide alcohol generated by hydrogenation of maltose and exhibiting resistance to intestinal disaccharidases. We demonstrated previously that maltitol stimulates transepithelial transport of calcium in the ileum, accompanied by an elevation of intestinal calcium absorption as well as calcium retention in the body. In this study, we examined whether the maltitol-induced increase in intestinal calcium absorption leads to an alteration of the physical properties of bones in rats subjected to ovariectomy. We used this study as a simulation model for postmenopausal females who are at risk for osteoporosis. Following the intake of a low-calcium diet for 28 d ovariectomized rats were fed diets containing either 10% maltose (control) or 10% maltitol, together with increased amounts of calcium (0.3% in Experiment 1 and 1.2% in Experiment 2) for 21 d. Balance studies performed during the final 5-d (Experiment 1) or 2-d (Experiment 2) period of the experiments showed that maltitol increased intestinal calcium absorption and retention. The breaking force of femoral bones was significantly elevated (by 5-7%) in animals fed the maltitol diet compared with that in rats fed the maltose diet. The calcium content in the femoral bones as well as the mineral bone density of the tibial metaphysis was also elevated in rats fed the maltitol diet. These results indicate that maltitol stimulates the intestinal absorption of dietary calcium leading to an increase in calcium content in the bone, and coinciding with the elevation of the breaking strength of the bone in ovariectomized rats.

Analysis of Variance↗
PubMed1995

Unsaturated fatty acids regulate gene expression of cellular retinol-binding protein, type II in rat jejunum.

We have shown that cellular retinol-binding protein, type II (CRBP II) mRNA and its protein levels are elevated in the jejunum of rats fed a diet rich in long-chain triacylglycerols. In the present study, we explored which types of fatty acids modulate CRBP II gene expression. Rats previously fed a low fat, high starch diet were force-fed a basal fat-free diet or the diet supplemented with 0.21 mol/L of various fatty acids (i.e., caprylic, palmitic, stearic, oleic, linoleic and alpha-linolenic acids). Force-feeding a diet containing linoleic acid produced an elevation of CRBP II mRNA levels in rats in both a dose-dependent (0.053-0.21 mol/L) and time-dependent (up to 6 h) manner. Among fatty acids tested, all unsaturated fatty acids (oleic, linoleic and alpha-linolenic acids) were able to enhance CRBP II mRNA levels by 54-63% within 6 h, whereas a medium-chain fatty acid (caprylic acid) and a saturated fatty acid (stearic acid) elicited little effect on the CRBP II mRNA levels; palmitic acid produced only a small elevation (16%) of the CRBP II mRNA level. Transcripts of both retinoid X receptor alpha and peroxisome proliferator-activated receptor (PPAR), which are thought to interact as a heterodimer with the cis-element located in the CRBP II promoter and to be activated by 9-cis retinoic acid and long-chain fatty acids, respectively, were constitutively expressed in the rat jejunum.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Consumption of excess vitamin A, but not excess beta-carotene, causes accumulation of retinol that exceeds the binding capacity of cellular retinol-binding protein, type II in rat intestine.

We assessed the effects of excess dietary vitamin A or beta-carotene on the cellular retinol-binding protein, type II [CRBP(II)] level and activities of lecithin: retinol acyltransferase (LRAT) and acyl-CoA:retinol acyltransferase (ARAT) in rat intestine. Male rats were fed for 7 d diets containing amounts of retinyl acetate or beta-carotene that were 1 (control), 10, 100 and 1000 times the NRC recommended requirement. No responses of the jejunal CRBP(II) level to an intake of excess vitamin A or beta-carotene were observed. The unesterified retinol and retinyl palmitate concentrations in the jejunum were small in rats fed 10 times the vitamin A requirement but they were significantly greater in rats fed 100 and 1000 times the vitamin A requirement than in controls. The molar ratio of unesterified retinol/CRBP(II) was < 1 for the controls and the group fed 10 times the vitamin A requirement, but > 3 for the group fed 100 times the requirement and > 19 for the group fed 1000 times the requirement. The LRAT activity was significantly greater in rats fed 1000 times the vitamin A requirement compared with all other groups, but ARAT activity was unaffected. Consumption of excess beta-carotene did not alter LRAT or ARAT activity, and led to a very small deposition of unesterified retinol and retinyl palmitate in the jejunum. Because CRBP(II) may play an important role in preventing the toxic effect of unbound retinol in the small intestine, consumption of excess vitamin A in amounts < 10 times the NRC recommended requirement may not cause a disturbance of the absorptive cell function.(ABSTRACT TRUNCATED AT 250 WORDS)

Acyltransferases↗
PubMed1995

Diet-induced changes in gene expression of lactase in rat jejunum.

To explore the mechanisms by which jejunal lactase activity is modified by carbohydrate and/or fat intake, mRNA levels and the absolute synthesis rate of lactase-phlorizin hydrolase (LPH) were determined in 6-wk-old rats that were fed either low-starch diets containing long-chain triacylglycerol (LCT, 73% energy as corn oil) or medium-chain triacylglycerol (MCT, 66% energy as MCT, 7% energy as corn oil), or a high-starch diet (70% energy as cornstarch) for 7 days. LPH mRNA levels in the jejunum were similar between LCT-fed and MCT-fed rats, but animals fed the high-starch diet exhibited a greater (2x) LPH mRNA level than other groups. The absolute synthesis rate of LPH, estimated by the flooding dose technique using [3H]phenylalanine, was greater (2.4x) in rats fed the high-starch diet than in other groups. A short-term force-feeding experiment revealed that sucrose was able to evoke LPH mRNA levels within 12 h but that a nonmetabolizable sugar (alpha-methylglucoside) was unable to enhance it. By contrast, animals fed the high-LCT diet showed a lower (by 30%) lactase activity than rats fed the low-starch, high-MCT diet, which was accompanied by not only a reduction of immunoreactive LPH in brush-border membranes but also a reduction in lactase activity per unit weight of immunoreactive LPH. These results suggest that both gene expression and posttranslational events of LPH might be influenced by dietary manipulations; carbohydrate intake primarily increases LPH mRNA levels, and LCT accelerates inactivation and/or degradation of lactase.

Animals↗
PubMed1995

WS75624 A and B, new endothelin converting enzyme inhibitors isolated from Saccharothrix sp. No. 75624. I. Taxonomy, fermentation, isolation, physico-chemical properties and biological activities.

Novel endothelin converting enzyme (ECE) inhibitors, WS75624 A and B, have been isolated from the fermentation broth of Saccharothrix sp. No. 75624. These inhibitors were purified from an acetone extract of whole culture broth followed by HP-20 column chromatography, silica gel column chromatography and HPLC. WS75624 A and B showed highly potent ECE inhibitory activity, and both had IC50 values of 0.03 microgram/ml. WS75624 A and B also showed other metalloprotease (collagenase and neutral endopeptidase) inhibitory activity with IC50 values of 1 microgram/ml. Since large amount of WS75624 B was isolated, we tried in vivo evaluation using WS75624 B. WS75624 B inhibited big endothelin-induced pressor effect when administered to SD rat intravenously with big ET-1.

Animals↗
PubMed1995

A new aromatase inhibitor, FR901537. I. Taxonomy, fermentation, isolation, physiochemical characteristics and biological activities.

FR901537 is a new aromatase inhibitor produced by a bacterium Bacillus sp. No. 3072. Structural studies of FR901537 suggested that it was a novel naphthol derivative having pantetheine in its structure. FR901537 showed a potent inhibitory activity against aromatase from human placenta or rat ovary, but did not inhibit the activity of 11 beta-hydroxylase from bovine adrenal cortex. Lineweaver-Burk plot analysis revealed that FR901537 is a competitive inhibitor.

Animals↗
PubMed1995

[Cerebellin in the cerebellum in spinocerebellar degeneration].

To clarify the possible pathophysiological role of cerebellin in spinocerebellar degeneration, immunoreactive cerebellin was measured in the postmortem brain of 4 patients with spinocerebellar degeneration and 4 controls. Three other representative neuropeptides, corticotropin releasing hormone (CRH), neuropeptide Y and somatostatin, were also measured. Significant decreases in the concentration of immunoreactive cerebellin and immunoreactive CRH were found in the cerebellar hemisphere in spinocerebellar degeneration, suggesting an important pathophysiological role of cerebellin and CRH in this group of diseases. No such decreases were found in neuropeptide Y or somatostatin.

Adult↗
PubMed1995

[Retrospective analysis of postoperative chemotherapy with UFT against pancreatic cancer].

The retrospective study was carried out to evaluate the effect of UFT given orally in patients with histologically proven pancreatic cancer in our institutions for 6 years. The study regimen was designed as follows: 400 or 600 mg/body UFT per day after the patients having something solid evidences of tumor. For 6 years, 78 patients were entered in this protocol. Further details of the patients characteristics were as follows: head 47 (60.3%) cases, tail & body 31; resection cases 26 (33.3%), palliative 52; Stage IV 62 (79.5%) cases. Resection, P (peritoneal dissemination). H (liver metastasis) and T (tumor size) were statistically proven to be significant prognostic factors. The median survival time of UFT group was 204 days and that of non UFT group was 123 days. According to the retrospective analysis, there was a significant difference in the cumulative survival rate between UFT group and non UFT group with 1.98 of Hazard's proportional ratio (p = 0.009). However, further clinical investigations-prospective study are necessary to confirm these data.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

[Meningeal seeding of spinal cord glioblastoma multiforme without any signs of myelopathy].

An autopsy case of meningeal spreading of glioblastoma multiforme (GBM) probably originating in the cervical cord was reported. In contrast to autopsy findings, main symptoms were similar to subacute meningitis, and any signs of myelopathy could not be detected during the clinical course. The patient was a 22-year-old man who was hospitalized because of a 2-week history of progressive headache following cough and slight fever. Vomiting and somnolence, developing 5 days before admission, were improved the day after a lumbar puncture performed at another hospital. On admission, meningeal signs, mild right abducens palsy, and depressed deep tendon reflexes were detected. There was no muscle weakness, sensory loss, or Babinski sign. Lumbar puncture yielded CSF with an opening pressure of 280 mmH2O, 21 mononuclear cells/mm3, a protein level of 645 mg/dl, and a glucose level of 7 mg/dl. Cytology for malignancy and multiple cultures were negative. Brain CT scan showed mild hydrocephalus and swelling of the brainstem and cerebellum. Intravenous administration of antimicrobial drugs was started and ventriculoperitoneal shunt surgery was performed. During the third hospital week, however, meningeal signs progressed and somnolence reappeared, followed by progressive multiple cranial neuropathy and polyradiculopathy characterized by flaccid tetraparesis, muscle atrophy, and sensory impairment without a level. Babinski sign could not be detected. MRI revealed an intramedullary lesion in the lower cervical cord, swelling of the brainstem, cerebellum, spinal cord and nerve roots, and a diffuse or nodular thickning of leptomeninges. Repeated CSF cytology disclosed atypical cells. Examinations for extraneural malignancies were negative. During the 9th hospital week, flaccid tetraplegia progressed and stupor developed, and the patient died 2 weeks later. The pathological study was limited to the brain. The brain showed a diffuse opalescent thickening of the leptomeninges, especially over the ventral aspect of the brainstem and cerebellum, where the blood vesseles and cranial nerves were obscured. Histological examination revealed the appearance of GBM. The malignant cells filled the subarachnoid space, and to a variable extent penetrated the brainstem and cerebellum along perivascular spaces. Hypertrophied optic tracts and trigeminal nerves were also infiltrated by the cells. However, there were no mass lesions assumed to be primary ones anywhere in the cerebral parenchyma. Therefore, it was thought that GBM primarily growing in cervical cord metastasized to intracranial subarachnoid space by way of the cerebrospinal fluid pathway. Spinal cord GBM usually presents signs of myelopathy from the early stage. The present case was characterized by no signs of myelopathy during the clinical course. It is speculated that the intramedullary GBM, originating near the surface of cervical cord, had been rapidly disseminated into the subarachnoid space up to the intracranial cavity before myelopathy appeared, and caused cranial and spinal nerve roots dysfunction, which covered signs of myelopathy. Cord GBM should be always considered as a differential diagnesis in a case of subacute meningitis.

Adult↗
PubMed1994

Dietary fat regulates cellular retinol-binding protein II gene expression in rat jejunum.

Cellular retinol-binding protein II (CRBP II) is an abundant cytosolic protein of intestinal absorptive cells. In this study, we examined whether dietary fat modulates the expression of CRBP II in the small intestine. In the rats fed a diet rich in long-chain triacylglycerols (LCT), both CRBP II mRNA and CRBP II protein levels in the jejunum were more than two-fold greater than in the rats fed a low fat diet and a diet rich in medium-chain triacylglycerols (MCT). The mRNA abundance of a retinoid X receptor (RXR alpha), which is thought to interact with the cis-element located in the CRBP II promoter, was elevated in the jejunum of rats fed high-LCT and high-MCT diets as compared with that of animals fed a low-fat diet, but the levels of RXR alpha mRNA of the LCT diet group was similar to that of MCT diet group. These results suggest that the expression level of the CRBP II gene is not directly related to the RXR alpha expression, and that it might be modulated by long-chain fatty acids or their metabolites.

Animals↗
PubMed1994

Dietary carbohydrate and fat independently modulate disaccharidase activities in rat jejunum.

The role of carbohydrate and fat in diet-induced modifications of jejunal disaccharidase activities was evaluated with an isoenergic diet containing a nonmetabolizable sugar, alpha-methylglucoside. Rats previously fed a high fat, low starch diet or a high starch low fat diet were force-fed three times over 12 h isoenergic high fat diets with or without alpha-methylglucoside, or a low fat diet containing alpha-methylglucoside. Regardless of the previous diet fed, force-feeding the high fat, alpha-methylglucoside diet produced significantly greater sucrase and lactase activities in the upper jejunum than force-feeding the high fat diet without alpha-methylglucoside; comparable or only slightly greater sucrase and lactase activities were seen in the lower jejunum. The animals fed the low fat, alpha-methylglucoside diet exhibited significantly greater sucrase and lactase activities in the lower jejunum than did the rats fed the high fat, alpha-methylglucoside diet; a less marked difference (< 30%) was observed between these two groups for disaccharidase activities in the upper jejunum. The lower sucrase and lactase activities observed in the jejunum of animals force-fed the high fat diet after consuming the high starch, low fat diet were accompanied by greater trypsin activity in the lumen of the upper and lower jejunum, suggesting that proteolytic degradation of sucrase and lactase might be stimulated in rats fed the high fat diets. These results suggest that both dietary carbohydrate and dietary fat independently and by different mechanisms modulate jejunal disaccharidase activities.

Animals↗
PubMed1994

Effect of dietary fat content on microvillus in rat jejunum.

To examine whether dietary manipulation of isoenergic diets might affect microvillar structure of small intestinal epithelial cells, morphological parameters of enterocytes and microvilli in the mid-villus portion of jejunum were determined in the rats fed either high-starch (70 energy %), low-fat (7 energy %) diet or high-fat (73 energy %), low-starch (5 energy %) diet for 7 days. Feeding the high-fat diet produced an increase in the height of villus, in accordance with the elevated jejunal mucosal weight and total protein contents as compared with the high-starch diet. No appreciable change in crypt depth occurred. Scanning electron microscopy of jejunal epithelial cells revealed that the morphometrical parameters of the villus cells were unchanged by the diets, but the microvillar structure of each villus cell was influenced by the diets; the animals fed the high-fat diet exhibited a reduced length (28%) of microvillus with a slight increase (12%) in diameter, showing a significantly reduced surface area of microvilli per enterocyte. The reduction in microvillar surface area of animals fed the high-fat diet was accompanied by the decrease in total proteins of the brush border membranes as well as the decrease in the activities of microvillar stalked disaccharidases, i.e., sucrase-isomaltase and lactase. These results provide an evidence that dietary manipulation, even when diets are "complete" in terms of the content of energy, protein, and other micronutrients, can modify the microvillar structure of small intestinal epithelial cells, leading to alterations in the digestive/absorptive surface area of villus cells.

Animals↗
PubMed1994

Monostearoylglycerol-starch complex: its digestibility and effects on glycemic and lipogenic responses.

We examined whether a modification of a starch into an alpha-amylase resistant form can lead to a reduction of postprandial glucose and insulin responses, and consequently to a change of lipid metabolism in liver and adipose tissue. For this purpose, a processed starch was prepared using a cornstarch (70% amylose and 30% amylopectin) and monoacylglycerol (monostearate; MS), forming monostearate-starch complex (MS-treated cornstarch). When we determined in vitro hydrolysis of MS-treated cornstarch using alpha-amylase and intestinal microvillar alpha-glucosidases, the glucose production rate of the MS-treated cornstarch was slower than the non-treated cornstarch. Measurement of a transmural potential difference (delta PD) evoked by the MS-treated cornstarch in everted rat jejunum showed that the absorption rate of glucose released from the MS-treated cornstarch was also remarkably slower than that from the non-treated cornstarch. The postprandial plasma insulin response to the MS-treated cornstarch was reduced, although plasma glucose response was unchanged. In a feeding study, two groups of five or six male Wistar-strain rats were fed defined diets containing 61.1% MS-treated cornstarch or 58.2% non-treated cornstarch ad libitum for 14 days. Food intakes during the period were similar between the two groups. Feeding the MS-treated cornstarch resulted in a significantly lower maltase activity in upper jejunum than did the non-treated cornstarch feeding. The activities of lipogenic enzymes--fatty acid synthetase (FAS), malic enzyme (ME), and glucose-6-phosphate dehydrogenase (G-6-PDH)--significantly decreased in epididymal adipose tissue of rats fed the MS-treated cornstarch. In the liver, FAS activity was lower in the MS-treated cornstarch group. The results indicated that MS-treated cornstarch was digested less rapidly, and lowered blood insulin response, consequently leading to a declined lipogenesis of adipose tissue and liver. This study suggests that the rate of intestinal hydrolysis of starch is an important determinant of metabolic responses such as glycemic and lipogenic responses to diets.

Adipose Tissue↗
PubMed1994

FR901451, a novel inhibitor of human leukocyte elastase from Flexibacter sp. I. Producing organism, fermentation, isolation, physico-chemical and biological properties.

A novel human leukocyte elastase (HLE) inhibitor, FR901451 was discovered in the fermentation broth of a bacteria. The bacteria was identified as Flexibacter sp. No. 758. FR901451 has a molecular weight of 1269 and a molecular formula of C60H79N13O18. The mode of inhibition against HLE is competitive, with a Ki value of 9.8 x 10(-9) M.

Animals↗