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T Hase

Publications and source records attributed to T Hase.

At least 19 recordsLinked to original sources
PubMed2005

Tenascin-C regulates proliferation and migration of cultured astrocytes in a scratch wound assay.

Tenascin-C (TNC), an extracellular matrix glycoprotein, is involved in tissue morphogenesis like embryogenesis, wound healing or tumorigenesis. Astrocytes are known to play major roles in wound healing in the CNS. To elucidate the roles of TNC in wound closure by astrocytes, we have examined the morphological changes of cultured astrocytes in a scratch wound assay and measured the content of soluble TNC released into the medium. We have also localized the expression of TNC mRNA, TNC, glial fibrillary acidic protein (GFAP), vimentin and integrin beta1. After wounding, glial cells rapidly released the largest TNC isoform and proliferated in the border zones. Subsequently, they became polarized with unidirectional processes and finally migrated toward the denuded area. The proliferating border zone cells and pre-migratory cells intensely expressed TNC mRNA, TNC-, vimentin-, GFAP- and integrin beta1-like immunoreactivity, while the migratory cells showed generally reduced expression except the front. Exogenous TNC enhanced cell proliferation and migration, while functional blocking with anti-TNC or anti-integrin beta1 antibody reduced both of them. These results suggest that mechanical injury induces boundary astrocytes to produce and release TNC that promotes cell proliferation and migration via integrin beta1 in an autocrine/paracrine fashion.

Animals↗
PubMed2005

Expression of peroxisome proliferator-activated receptor-gamma in renal ischemia-reperfusion injury.

The pathogenesis of ischemia-reperfusion injury is known to involve cytokines and particularly surface adhesion molecules, the expression of which initiates the attachment of inflammatory cells. Peroxisome proliferator-activated receptor (PPAR)-gamma is considered an important immunomodulatory factor as well as a fatty acid regulator. In this study, we researched the expression of PPAR-gamma in renal ischemia-reperfusion injury of the rat. The right kidney was harvested and left renal artery and vein were clamped under laparotomy. The kidney was reperfused after 90 minutes of ischemia, and rats were sacrificed at 0, 1.5, 3, 5, 12, and 24 hours after reperfusion. PPAR-gamma expression was analyzed by immunohistochemical staining using monoclonal antibody. In normal kidney, PPAR-gamma staining was weak on endothelial cells, including mesangial cells. On the other hand, PPAR-gamma staining was weak on interstitial cells and strong on collecting ducts of medulla. From 1.5 to 5 hours after reperfusion, PPAR-gamma staining was strong on endothelial cells, moderate on interstitial cells, and strong on collecting ducts. Twelve hours after reperfusion, PPAR-gamma staining was weak on endothelial cells, moderate on interstitial cells, and strong on collecting ducts. PPAR-gamma is induced on collecting ducts, interstitial cells, and endothelial cells in a rat model having renal ischemia-reperfusion injury.

Animals↗
PubMed2004

The expression of cyclooxygenases and lipoxygenases in renal ischemia-reperfusion injury.

Recent studies of ischemia-reperfusion (I/R) injury have focused on the function of neutrophils as well as the actions of inflammatory cytokines. However, few reports address cyclooxygenases (COXs) and lipoxygenases (LOXs). We researched the expression of COXs (COX-1 and COX-2) and LOXs (5-LOX and 12-LOX) in rat renal I/R injury. The right kidney of male Lewis rats was excised, and the left renal artery and vein clamped for a 90-minute ischemia time. Rats were humanely killed at 0, 1.5, 3, 5, and 12 hours after reperfusion. COX and LOX expressions were studied using immunohistostaining. COX-2 and LOX expressions were observed only on endothelial cells of normal kidney. From 1.5 to 5 hours after reperfusion, COX-2 and LOXs expressions gradually intensified on endothelial cells. COX-2 and LOXs expression were most intense on endothelial cells at 5 hours after reperfusion. Twelve hours after reperfusion, necrosis extended throughout the ischemic kidney and nearly all the tubular epithelial cells were destroyed. Thus, at 12 hours after reperfusion, COX-2 and LOXs expressions on endothelial cells became weaker. However, COX-1 expression was not different at every time after reperfusion. COX-2 and LOXs were expressed in a rat model showing renal I/R injury. Several hours after the maximum of COX-2 and LOXs expressions, the maximal renal I/R injury was observed. These results suggest a relationship between COX-2 and LOXs expressions and renal I/R injury.

Animals↗
PubMed2003

Cyclooxygenase-1 and -2 in human testicular tumours.

In this study, we investigated the expression of cyclooxygenase (COX)-1 and -2 in human testicular cancer (TC) and normal testis (NT) tissues, as well as the effects of COX ligands on viability and proliferation. Tumour specimens were obtained from 72 patients with TC and 20 patients with NT. RT-PCR and immunohistochemical methods were used to determine COX expression. While COX expression was not noted in any of the NT tissues, a marked expression was observed in the TC samples. The extent and intensity of immunoreactive COX-1 and -2 polypeptides in the TC tissues was statistically greater than the expression in the NT tissues. The synthetic COX inhibitors inhibited the growth of the TC cells. Both COX-1 and COX-2 are induced in testicular cancer, and these results indicate that both COX-1 and COX-2 are essential for the growth of TC cells.

Adult↗
PubMed2002

Accelerated reaction by loop-mediated isothermal amplification using loop primers.

Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid amplification method that amplifies DNA with high specificity, efficiency and rapidity under isothermal conditions using a set of four specially designed primers and a DNA polymerase with strand displacement activity. We have developed a method that accelerates the LAMP reaction by using additional primers, termed loop primers. Loop primers hybridize to the stem-loops, except for the loops that are hybridized by the inner primers, and prime strand displacement DNA synthesis. Although both inner and loop primers react via the loops, they do so by different mechanisms. The LAMP method presented here uses loop primers to achieve reaction times of less than half that of the original LAMP method. Since the total time of analysis including detection is less than 1h, this new method should facilitate genetic analysis, including genetic diagnosis in the clinical laboratory.

Base Sequence↗
PubMed2002

Autoimmune thyroid disease accompanied by recurring episodes of painful thyroid ameliorated by thyroidectomy.

A 71-yr-old female initially presented with clinical and biochemical hyperthyroidism with high TSH binding inhibitory immunoglobulin (TBII) and anti-thyroid peroxidase antibody (TPOAb) titers. Histological findings of the thyroid revealed hyperplasia with a focal germinal center, indicating Graves' disease and mild focal chronic thyroiditis. Four episodes of painful and tender thyroid occurred over the next 2 yr accompanied by acute inflammatory reactions. The first episode that developed while the patient was in a hyperthyroid state was soon followed by hypothyroidism associated with further increases in anti-thyroglobulin antibody (TGAb) and TPOAb titers. The subsequent 3 episodes occurred during the hypothyroid state, when the TGAb titer progressively increased with each episode. We performed subtotal thyroidectomy to prevent further episodes. Specimens obtained at thyroidectomy showed that extreme fibrosis had replaced the thyroid parenchyma with collapsed follicles and moderate lymphocyte infiltration. No further episodes occurred after thyroidectomy, and during a 3-yr follow-up period, TBII and thyroid-stimulating antibody (TSAb) disappeared and TGAb and TPOAb titers decreased. This case report provides further evidence supporting the notion that thyroid epithelial destruction progresses during relatively short periods of recurrent painful thyroid and that thyroidectomy helps patients affected by this condition that are unresponsive to other treatment strategies.

Aged↗
PubMed2002

Beneficial effects of tea catechins on diet-induced obesity: stimulation of lipid catabolism in the liver.

OBJECTIVE: Obesity has increased at an alarming rate in recent years and is now a worldwide health problem. We investigated the effects of long-term feeding with tea catechins, which are naturally occurring polyphenolic compounds widely consumed in Asian countries, on the development of obesity in C57BL/6J mice. DESIGN: We measured body weight, adipose tissue mass and liver fat content in mice fed diets containing either low-fat (5% triglyceride (TG)), high-fat (30% TG), or high-fat supplemented with 0.1-0.5% (w/w) tea catechins for 11 months. The beta-oxidation activities and related mRNA levels were measured after 1 month of feeding. RESULTS: Supplementation with tea catechins resulted in a significant reduction of high-fat diet-induced body weight gain, visceral and liver fat accumulation, and the development of hyperinsulinemia and hyperleptinemia. Feeding with tea catechins for 1 month significantly increased acyl-CoA oxidase and medium chain acyl-CoA dehydrogenase mRNA expression as well as beta-oxidation activity in the liver. CONCLUSION: The stimulation of hepatic lipid metabolism might be a factor responsible for the anti-obesity effects of tea catechins. The present results suggest that long-term consumption of tea catechins is beneficial for the suppression of diet-induced obesity, and it may reduce the risk of associated diseases including diabetes and coronary heart disease.

Adipose Tissue↗
PubMed2001

Passive monitoring method for 3-ethenylpyridine: a marker for environmental tobacco smoke.

A new method was developed to assess environmental tobacco smoke in air. The method is based on passive sampling and subsequent measurement of the concentration of 3-ethenylpyridine, a vapor-phase compound specific to tobacco smoke. Air samples were collected using a 3M organic vapor monitor. Tests were carried out in a dynamic chamber to determine the sampling rate (25.7 cm3/min). 3-Ethenylpyridine was desorbed from the sampler with 1 mL of pyridine/toluene mixture. 3-Ethenylpyridine was quantified by gas chromatography/mass spectrometry. The limit of detection was 0.01 microgram/sample, corresponding to a concentration of 0.27 microgram/m3 air calculated for a sampling period of 24 h. Field measurements were carried out to test the performance of the method. Mean concentrations ranging from 1.3 to 5.3 micrograms/m3 were measured for 3-ethenylpyridine in smoking environments, but no 3-ethenylpyridine was detected in nonsmoking environments. Active sampling using charcoal tubes was used as a reference method in the chamber tests and field measurements. Individual exposures can be easily and accurately measured by means of the passive sampler. Because of simple sample treatment, the method is also well-suited for large-scale monitoring of environmental tobacco smoke.

Air Pollutants↗
PubMed2001

Attractin/mahogany/zitter plays a critical role in myelination of the central nervous system.

The rat zitter (zi) mutation induces hypomyelination and vacuolation in the central nervous system (CNS), which result in early-onset tremor and progressive flaccid paresis. By positional cloning, we found a marked decrease in Attractin (Atrn) mRNA in the brain of the zi/zi rat and identified zi as an 8-bp deletion at a splice donor site of Atrn. Atrn has been known to play multiple roles in regulating physiological processes that are involved in monocyte-T cell interaction, agouti-related hair pigmentation, and control of energy homeostasis. Rat Atrn gene encoded two isoforms, a secreted and a membrane form, as a result of alternative splicing. The zi mutation at the Atrn locus darkened coat color when introduced into agouti rats, as also described in mahogany (mg) mice, carrying the homozygous mutation at the Atrn locus. Transgenic rescue experiments showed that the membrane-type Atrn complemented both neurological alteration and abnormal pigmentation in zi/zi rats, but that the secreted-type Atrn complemented neither mutant phenotype. Furthermore, we discovered that mg mice exhibited hypomyelination and vacuolation in the CNS associated with body tremor. We conclude from these results that the membrane Atrn has a critical role in normal myelination in the CNS and would provide insights into the physiology of myelination as well as the etiology of myelin diseases.

Agouti Signaling Protein↗
PubMed2001

Abundant expression of uncoupling protein-2 in the small intestine: up-regulation by dietary fish oil and fibrates.

Mitochondrial uncoupling protein-2 (UCP-2) is widely expressed in various mammalian tissues, although its physiological functions are not well understood. We examined the effects of dietary fish oil on UCP-2 expression in the rat small intestine, in which UCP-2 mRNA levels are higher than in other organs. Feeding with fish oil (20%) up-regulated UCP-2 mRNA within 6 days in the small intestine as well as the liver, compared to feeding with soybean oil. This was mimicked by feeding with agonists for peroxisome proliferator-activated receptor alpha (PPARalpha) such as fenofibrate and bezafibrate, but not the PPARgamma agonist troglitazone. The bezafibrate-induced increase in UCP-2 expression was found within 2 days in the small intestine, but only after 6 days in the liver. The up-regulation of UCP-2 was also found in cultured intestinal epithelial cells (IEC-6) treated for 24 h with various long-chain fatty acids and PPARalpha agonists. These results indicated that intestinal UCP-2 is up-regulated through direct activation of PPARalpha by dietary fatty acids.

Animals↗
PubMed2001

The 70-kDa major DNA-compacting protein of the chloroplast nucleoid is sulfite reductase.

The chloroplast nucleoid is a complex of chloroplast DNA and various, mostly uncharacterized proteins. An abundant 70-kDa protein of the isolated nucleoids of pea chloroplasts was identified as sulfite reductase by N-terminal sequence analysis as well as immunoblot analysis, spectrophotometry and enzyme activity analysis. Recombinant maize sulfite reductase was indeed able to compact chloroplast DNA and to form nucleoid-like particles in vitro. The role of sulfite reductase in the structural organization of the nucleoid is discussed.

Amino Acid Sequence↗
PubMed2001

Techniques available for the management of massive sacrococcygeal teratomas.

An infant born in the 34th week of gestation weighing 5,355 g with a massive sacrococcygeal (SC) tumor was delivered by elective cesarean section. An ultrasonographic examination showed solid and cystic components in the tumor. Resection was successfully undertaken with insertion of a Nélaton catheter into the rectum to avoid unnecessary impairment of the viscera. The tumor weighed 2,380 g, measured 25 x 14 x 11 cm, and was clinicopathologically diagnosed to be a SC teratoma. This experience and other publications show that several considerations including control of hemorrhage and coagulopathies, visceral protection, and avoidance of wound infection are necessary to facilitate the surgical management of massive SC tumors. Several suggestions are made concerning the pre- and intraoperative management of this rare tumor.

Female↗
PubMed2001

Sulfated polysaccharides, but not cellulose, increase colonic mucus in rats with loperamide-induced constipation.

Colonic mucus is decreased in a rat model of spastic constipation, and some types of water-insoluble dietary fiber increase colonic mucus when consumed by rats for several weeks. However, little is known about the effect of water-soluble dietary fiber on the colonic mucus. The aim of the present study was to investigate the effect of various types of water-soluble dietary fiber on colonic mucus in a rat model of spastic constipation. Oral administration of 1.5 mg/day of carrageenan and chondroitin sulfate increased the fecal excretion, epithelial mucin production, thickness of the mucous layer, and amount of luminal mucus in loperamide-administered rats. Sodium alginate, 5 mg/day, thickened the mucus layer at the fecal surface. Cellulose, 5 mg/day, increased the fecal excretion but not the colonic mucus. Carrageenan, chondroitin sulfate, and sodium alginate, but not cellulose, increased colonic mucus in the rat model of spastic constipation.

Alginates↗
PubMed2001

Structure of the electron transfer complex between ferredoxin and ferredoxin-NADP(+) reductase.

All oxygenic photosynthetically derived reducing equivalents are utilized by combinations of a single multifuctional electron carrier protein, ferredoxin (Fd), and several Fd-dependent oxidoreductases. We report the first crystal structure of the complex between maize leaf Fd and Fd-NADP(+) oxidoreductase (FNR). The redox centers in the complex--the 2Fe-2S cluster of Fd and flavin adenine dinucleotide (FAD) of FNR--are in close proximity; the shortest distance is 6.0 A. The intermolecular interactions in the complex are mainly electrostatic, occurring through salt bridges, and the interface near the prosthetic groups is hydrophobic. NMR experiments on the complex in solution confirmed the FNR recognition sites on Fd that are identified in the crystal structure. Interestingly, the structures of Fd and FNR in the complex and in the free state differ in several ways. For example, in the active site of FNR, Fd binding induces the formation of a new hydrogen bond between side chains of Glu 312 and Ser 96 of FNR. We propose that this type of molecular communication not only determines the optimal orientation of the two proteins for electron transfer, but also contributes to the modulation of the enzymatic properties of FNR.

Binding Sites↗
PubMed2001

Solubilization of phytosterols in diacylglycerol versus triacylglycerol improves the serum cholesterol-lowering effect.

OBJECTIVE: This study was performed to investigate the difference in the serum-cholesterol- and triglyceride-lowering activities between phytosterols dissolved in diacylglycerol (PS/DG) and dispersed in triacylglycerol (PS/TG). The effects of the solvent on the concentrations of serum beta-sitosterol and campesterol were examined. DESIGN: The study had a randomised crossover design. SUBJECTS: Twelve healthy normocholesterolemic or moderately hypercholesterolemic men aged 29-50 y participated in this study. INTERVENTIONS: For 2 weeks before the test period (designated as the control period), all subjects consumed control mayonnaise (PS free) daily with supper and were randomly assigned to two groups for the 2 week test period; one group was given mayonnaise containing PS (500 mg/day) dissolved in DG (10 g/day), and the other mayonnaise containing PS (500 mg/day) dispersed in TG (10 g/day). After a wash out period consuming control PS-free mayonnaise for 4 weeks, the groups were reversed for 2 weeks. RESULTS: PS/TG feeding had no effect on the serum cholesterol level. In contrast, PS/DG feeding significantly reduced the total and LDL cholesterol levels from the initial value of 5.57 to 5.31 mmol/l (4.7%; P<0.05) and from 3.69 to 3.39 mmol/l (7.6%; P<0.05), respectively. Moreover, the degree of total cholesterol reduction induced by PS/DG feeding in the test period was significantly greater than that induced by PS/TG feeding (P<0.05). In addition, the serum beta-sitosterol and campesterol concentrations did not change during the PS/TG or PS/DG feeding periods. CONCLUSIONS: Dissolution of PS in DG had a better serum cholesterol lowering effect than dissolution in TG. SPONSORSHIP: Kao Corporation.

Adult↗
PubMed2001

Are tobacco use and urine pH indicated as risk factors for bladder carcinoma?

BACKGROUND: Many case-control and cohort studies have shown a positive relationship between bladder carcinoma and tobacco use. Recently, urine pH has been reported to influence aromatic amine carcinogenesis, which have been implicated as potent carcinogens in bladder carcinoma patients. Herein the correlation between bladder carcinoma, tobacco use and urine pH is reported. METHOD: One hundred and forty-one patients with bladder carcinoma and 128 patients with benign prostatic hyperplasia or urolithiasis as controls were selected. All patients were admitted to Osaka City University Hospital for the purpose of surgical treatment. Urine pH was checked by a test tape. RESULTS: Of the patients with bladder carcinoma, 106 were smokers and 35 were non-smokers. In contrast, the number of smokers in the control group was 76 and that of non-smokers was 52. The odds ratio in the bladder carcinoma group calculated for the smoker patients was 2.07, showing a significant correlation between bladder carcinoma and tobacco use. Regarding urine pH, acidic urine was found in 126 patients in the bladder carcinoma group and in 116 patients in the control group. The odds ratio in the bladder carcinoma group for acidic urine was 0.87, showing no significant relationship between bladder carcinoma and urine pH. CONCLUSION: The study found a positive relationship between bladder carcinoma and tobacco use; however, it could not establish a clear relationship between bladder carcinoma and urine pH, even in the smoker group.

Aged↗