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991.
Miwa Fukuda Tomomi Sasaki Tomoko Hashimoto Hiroyuki Miyachi Minoru Waki Akira Asai Osamu Takikawa Osamu Ohno Kenji Matsuno 《Bioorganic & medicinal chemistry letters》2018,28(17):2846-2849
Kynurenine is biosynthesised from tryptophan catalysed by indoleamine 2,3-dioxygenase (IDO). The abrogation of kynurenine production is considered a promising therapeutic target for immunological cancer treatment. In the course of our IDO inhibitor programme, formal cyclisation of the isothiourea moiety of the IDO inhibitor 1 afforded the 5-Cl-benzimidazole derivative 2b-6, which inhibited both recombinant human IDO (rhIDO) activity and cellular kynurenine production. Further derivatisation of 2b-6 provided the potent inhibitor of cellular kynurenine production 2i (IC50?=?0.34?µM), which unexpectedly exerted little effect on the enzymatic activity of rhIDO. Elucidation of the mechanism of action revealed that compound 2i suppresses IDO expression at the protein level by inhibiting STAT1 expression in IFN-γ-treated A431 cells. The kynurenine-production inhibitor 2i is expected to be a promising starting point for a novel approach to immunological cancer treatment. 相似文献
992.
Background
High expectations regarding therapy are reported to have positive effects on future therapeutic course and related behavior. Some individuals are aware of feelings of comfort immediately after a relaxation therapy session.Methods
Heart rate variability biofeedback (HRV-BF) therapy using a relaxation technique called resonant breathing was administered to 44 family caregivers who felt burdened by their work caring for family members with cancer. We prospectively evaluated how the level of comfort participants were aware of immediately after an initial therapy session affected their expectations regarding the therapy, as well as future quality of life (QOL) and autonomic function. This study was a secondary analysis of a randomized, open-label study titled “Self-care system for family caregivers of cancer patients using resonant breathing with a portable home device”.Results
Among the participants, 56.8% were aware of a feeling of comfort immediately after an initial therapy session. Participants were then divided into two groups according to the presence or absence of their awareness of comfort. Expectation levels regarding the therapy were significantly increased in the awareness group after the therapy session (P?=?0.003). No main effect between groups was observed for heart rate variability (HRV) during therapy (P?=?0.949). Four weeks after the initial therapy session, QOL improved and HRV increased in the awareness group (P?<?0.001).Conclusions
Better outcomes in the awareness group were not associated with HRV during therapy. A feeling of comfort immediately after a therapy session may have positive effects on future QOL and autonomic function by raising participants’ expectations of the therapy.Trial registration
UMIN000021639. Registered 27 March 2016993.
This work focused on the characteristics of ethanol regulation from Monascus sp. NP1. in glucose liquid medium, a saccharification method using algae and bioethanol production from Cladophora glomerata by the fungus. The results showed that when the fungus was grown in glucose (2, 20, 40 and 50%) medium under 110 rpm rotary culture at 30 °C, the ethanol concentration at 120 h increased from 2 to 20% glucose, where it peaked. It then decreased gradually to 40%, with production stopping at 50% glucose. This result indicated the glucose regulation of ethanol production by the fungus. Ethanol present in 20% glucose medium was identified by retention time and co-injection with a standard to demonstrate that the product was ethanol. Its yield was 285 mM [13 g L?1 or 65 mg (g of glucose substrate)?1] with a low interference of by-products. Three-millimetre-long pieces of dried algae were cut and exposed to concentrations of 1, 2, 3, 4, 5 and 6 g in 65 mL of 0.3 N hydrochloric acid or sulfuric acid before autoclaving (121 °C, 15 psi, 15 min). The amount of reducing sugar was greater than that of the control (without acid treatment) and varied with the increasing quantity of algae. The best condition was sulfuric acid and 6 g dried algae. The type of acid appeared to affect saccharification. During 12 days of fermentation in algal extraction (2 g reducing sugar per millilitre algal extraction), the mould could produce twofold more ethanol yield [34–55 mg (100 g dried weight algae)?1] than the yeast, Saccharomyces cerevisiae TISTR 5049. 相似文献
994.
Kei Yabuki Joji Haratake Yojiro Tsuda Eisuke Shiba Hiroshi Harada Kenji Yorita Kazuyoshi Uchihashi Atsuji Matsuyama Keiji Hirata Masanori Hisaoka 《Biological trace element research》2018,185(1):36-47
Lanthanum (La) carbonate (LC) is one of the most potent phosphate binders that prevents the elevation of serum phosphate levels in patients with end-stage renal diseases undergoing dialysis. LC binds strongly to dietary phosphate and forms insoluble complexes that pass through the gastrointestinal tract. La deposition in patients treated with LC is a recently documented finding particularly observed in gastric mucosa. We herein describe the detailed gastric mucosal lesions in 45 LC-treated patients and address the potential underlying pathologic mechanism using oral LC administration in rats. Microscopically, La deposition, as shown by subepithelial collections of plump eosinophilic histiocytes or small foreign body granulomas containing coarse granular or amorphous inclusion bodies, was found in the gastric mucosa of 44 (97.8%) of the 45 dialysis patients in the study cohort, which was most frequently associated with foveolar hyperplasia (37.8%). Using oral administration of rats with 1000 mg/day LC for 2 or more weeks, La deposition was consistently detectable in the gastric mucosa but not in other organs examined. In addition, various histologic alterations such as glandular atrophy, stromal fibrosis, proliferation of mucous neck cells, intestinal metaplasia, squamous cell papilloma, erosion, and ulcer were demonstrated in the rat model. Thus, orally administered LC can induce mucosal injury, designated here as La gastropathy, which may alter the local environment and result in La deposition in the gastric mucosa, thereby potentially inducing abnormal cell proliferation or neoplastic lesions. 相似文献
995.
Masaru Sakurada Diego P. Morgavi Kenji Komatani Yoshifumi Tomita Ryoji Onodera 《Current microbiology》1997,35(1):48-51
An autolysis chitinase was purified from the cultural medium of the anaerobic fungus Piromyces communis OTS1 by ammonium sulfate precipitation, affinity chromatography with regenerated chitin, chromato-focusing, gel filtration,
and chromato-focusing again. The optimal pH and temperature were 6.0 and 50°C, respectively, for a 20-min assay. The chitinase
was stable from pH 6.0 to 8.0, but was unstable at 70°C for 20 min. The molecular mass of chitinase was estimated by SDS-PAGE
to be 44.9 kDa, and its pI was 4.4. The enzyme activity, which was of the ‘endo’ type, was inhibited by Hg2+ and allosamidin. The chitinase hydrolyzes chitin powder and fungal cell walls at a higher rate than an artificial chitin
substrate. It can be concluded that extracellular chitinase is similar to cytosolic chitinase, but they are not the same protein.
Received: 3 December 1996 / Accepted: 28 January 1997 相似文献
996.
Osada Kazumi; Komai Michio; Bryant Bruce P.; Suzuki Hitoshi; Goto Atsuko; Tsunoda Kenji; Kimura Shuichi; Furukawa Yuji 《Chemical senses》1997,22(3):249-255
Single-fiber preparations of the rat chorda tympani (CT) nervewere used to study the mechanism of action of capsaicin on salt-tastetransduction. Capsaicin selectively suppressed the responsesto NaCl of the CT nerve fibers (N-fibers) that are sodium-specific(insensitive or poorly sensitive to potassium). Among the morebroadly responsive, cation-sensitive fibers (E-fibers) thereare two subtypes, both of which responded to capsaicin but indifferent ways (enhanced type and suppressedtype). In both N- and E-fibers, 5% ethanol (the vehicle forcapsaicin) slightly reduced the response to 100 mM NaCl. Thesuppressive effect of capsaicin on the response of the N-typefibers to 100 mM NaCl was significantly stronger than the effectof 5% ethanol. The suppression lasted for at least 20 s afterthe simultaneous application of 100 p.p.m. capsaicin-100 mMNaCl. These results indicate that 100 p.p.m. capsaicin can modifythe response of CT fibers to NaCl. The observed effect of capsaicinon gustatory fibers could be the net result of opposite suppressiveand enhancing processes in the taste buds cells and excitedintra- or extragemmal trigeminal nerve endings. Chem. Senses22: 249255, 1997.
*These authors contributed equally to this study 相似文献
997.
998.
The production of IgA protease in twelve strains of Streptococcus sanguis isolated from patients with Behçet's disease (BD) was examined. Protease activity was detected in 10 out of 12 strains. The protease was purified from one representative strain, S. sanguis 113–20, by employing Rotofor and DEAE-Sephacel chromatography. The molecular mass of the purified protease was approximately 100 kDa, and it cleaved the proline-threonine site of the IgA. Both IgG and IgA titers against the cells (113–20) and the purified IgA protease in the sera of BD patients and healthy controls, 36 each, were assayed. The IgG titers against the cells and protease were not significant in the BD patients or controls, but the IgA titers against the cells and protease in the BD patients were significantly higher than those of the controls. These data indicate that the BD patients are infected with IgA protease-producing S. sanguis strains, which cause an increase of IgA titer against these organisms and IgA protease antigen. Since the organisms can proliferate in BD patients for a long period of time (years), it seems that IgA antibodies cannot effectively eliminate the organisms. 相似文献
999.
1000.
Kaori Ishida Takashi Murakami Akira Mizuno Mitsuru Iida Masamichi Kuwajima Kenji Shima 《Regulatory peptides》1997,70(2-3):179-182
The effects of leptin on insulin secretion from pancreatic islets of Sprague–Dawley rats were examined in vitro. In a basal glucose medium (5.5 mM), insulin secretion from isolated islets was significantly decreased after addition of a recombinant leptin (80 nM) (3.20±0.14 nmol/10 islets/h) compared with that before the addition (4.41±0.30 nmol/10 islets/h). Although significant leptin suppression of insulin secretion was not observed under a glucose-stimulated (11.1 mM) condition, these results suggest that a negative feedback system may exist between leptin and insulin, which increases the production of leptin from adipose tissues. 相似文献