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41.
Although 4-tert-butylphenol (4-t-BP) is a serious aquatic pollutant, its biodegradation in aquatic environments has not been well documented. In this study, 4-t-BP was obviously and repeatedly removed from water from four different environments in the presence of Spirodela polyrrhiza, giant duckweed, but 4-t-BP persisted in the environmental waters in the absence of S. polyrrhiza. Also, 4-t-BP was not removed from autoclaved pond water with sterilized S. polyrrhiza. These results suggest that the 4-t-BP removal from the environmental waters was caused by biodegradation stimulated by the presence of S. polyrrhiza rather than by uptake by the plant. Moreover, Sphingobium fuliginis OMI capable of utilizing 4-t-BP as a sole carbon and energy source was isolated from the S. polyrrhiza rhizosphere. Strain OMI degraded 4-t-BP via a meta-cleavage pathway, and also degraded a broad range of alkylphenols with linear or branched alkyl side chains containing two to nine carbon atoms. Root exudates of S. polyrrhiza stimulated 4-t-BP degradation and cell growth of strain OMI. Thus, the stimulating effects of S. polyrrhiza root exudates on 4-t-BP-degrading bacteria might have contributed to 4-t-BP removal in the environmental waters with S. polyrrhiza. These results demonstrate that the S. polyrrhiza–bacteria association may be applicable to the removal of highly persistent 4-t-BP from wastewaters or polluted aquatic environments.  相似文献   
42.
TNF activates three distinct intracellular signaling cascades leading to cell survival, caspase-8–mediated apoptosis, or receptor interacting protein kinase 3 (RIPK3)–dependent necrosis, also called necroptosis. Depending on the cellular context, one of these pathways is activated upon TNF challenge. When caspase-8 is activated, it drives the apoptosis cascade and blocks RIPK3-dependent necrosis. Here we report the biological event switching to activate necrosis over apoptosis. TAK1 kinase is normally transiently activated upon TNF stimulation. We found that prolonged and hyperactivation of TAK1 induced phosphorylation and activation of RIPK3, leading to necrosis without caspase activation. In addition, we also demonstrated that activation of RIPK1 and RIPK3 promoted TAK1 activation, suggesting a positive feedforward loop of RIPK1, RIPK3, and TAK1. Conversely, ablation of TAK1 caused caspase-dependent apoptosis, in which Ripk3 deletion did not block cell death either in vivo or in vitro. Our results reveal that TAK1 activation drives RIPK3-dependent necrosis and inhibits apoptosis. TAK1 acts as a switch between apoptosis and necrosis.  相似文献   
43.
In mammals, 5,8,11-eicosatrienoic acid (Mead acid, 20:3n − 9) is synthesized from oleic acid during a state of essential fatty acid deficiency (EFAD). Mead acid is thought to be produced by the same enzymes that synthesize arachidonic acid and eicosapentaenoic acid, but the genes and the pathways involved in the conversion of oleic acid to Mead acid have not been fully elucidated. The levels of polyunsaturated fatty acids in cultured cells are generally very low compared to those in mammalian tissues. In this study, we found that cultured cells, such as NIH3T3 and Hepa1–6 cells, have significant levels of Mead acid, indicating that cells in culture are in an EFAD state under normal culture conditions. We then examined the effect of siRNA-mediated knockdown of fatty acid desaturases and elongases on the level of Mead acid, and found that knockdown of Elovl5, Fads1, or Fads2 decreased the level of Mead acid. This and the measured levels of possible intermediate products for the synthesis of Mead acid such as 18:2n − 9, 20:1n − 9 and 20:2n − 9 in the knocked down cells indicate two pathways for the synthesis of Mead acid: pathway 1) 18:1n − 9 → (Fads2) → 18:2n − 9 → (Elovl5) → 20:2n − 9 → (Fads1) → 20:3n − 9 and pathway 2) 18:1n − 9 → (Elovl5) → 20:1n − 9 → (Fads2) → 20:2n − 9 → (Fads1) → 20:3n − 9.  相似文献   
44.

Background

Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults.

Methods

We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability).

Results and Discussion

Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults.

Conclusions

Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields.

Trial Registration

UMIN Clinical Trial Registry 000005618.  相似文献   
45.
Psoriasis is a persistent cutaneous disease characterized by skin inflammation and infiltration of immunocytes such as lymphocytes and monocytes/macrophages, concomitant with abnormal epidermal hyperproliferation. We previously showed that the serum level of macrophage migration inhibitory factor (MIF) and its production by peripheral blood mononuclear cells of patients with psoriasis were closely correlated with the severity of clinical symptoms; however, the precise role of MIF in psoriatic epidermis remains to be clarified. The current study was carried out to elucidate the possible involvement of MIF in psoriasis, using immunohistochemistry and in situ hybridization. In contrast to elevated serum MIF in psoriasis, MIF-positive staining in the lesional psoriatic epidermis was significantly decreased, as demonstrated by immunohistochemical analysis using an anti-MIF antibody. Consistent with this finding, we found, by in situ hybridization, that MIF mRNA concomitantly decreased in the psoriatic lesions. Although the reason for the different MIF levels in the psoriatic epidermis and in the circulation remains unknown, it is hypothesized that MIF, a potential growth factor, might be decreased in psoriatic lesions to counterregulate the abnormal epidermal proliferation caused by dysregulation of cytokines and growth factors.  相似文献   
46.
Despite the recent advances in the treatment of multiple myeloma (MM), MM patients with high-risk cytogenetic changes such as t(4;14) translocation or deletion of chromosome 17 still have extremely poor prognoses. With the goal of helping these high-risk MM patients, we previously developed a novel phthalimide derivative, TC11. Here we report the further characterization of TC11 including anti-myeloma effects in vitro and in vivo, a pharmacokinetic study in mice, and anti-osteoclastogenic activity. Intraperitoneal injections of TC11 significantly delayed the growth of subcutaneous tumors in human myeloma-bearing SCID mice. Immunohistochemical analyses showed that TC11 induced apoptosis of MM cells in vivo. In the pharmacokinetic analyses, the Cmax was 2.1 μM at 1 h after the injection of TC11, with 1.2 h as the half-life. TC11 significantly inhibited the differentiation and function of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated osteoclasts in mouse osteoclast cultures using M-CSF and RANKL. We also revealed that TC11 induced the apoptosis of myeloma cells accompanied by α-tubulin fragmentation. In addition, TC11 and lenalidomide, another phthalimide derivative, directly bound to nucleophosmin 1 (NPM1), whose role in MM is unknown. Thus, through multiple molecular interactions, TC11 is a potentially effective drug for high-risk MM patients with bone lesions. The present results suggest the possibility of the further development of novel thalidomide derivatives by drug designing.  相似文献   
47.
We assessed vaccine effectiveness (VE) against medically attended, laboratory-confirmed influenza in children 6 months to 15 years of age in 22 hospitals in Japan during the 2013–14 season. Our study was conducted according to a test-negative case-control design based on influenza rapid diagnostic test (IRDT) results. Outpatients who came to our clinics with a fever of 38°C or over and had undergone an IRDT were enrolled in this study. Patients with positive IRDT results were recorded as cases, and patients with negative results were recorded as controls. Between November 2013 and March 2014, a total of 4727 pediatric patients (6 months to 15 years of age) were enrolled: 876 were positive for influenza A, 66 for A(H1N1)pdm09 and in the other 810 the subtype was unknown; 1405 were positive for influenza B; and 2445 were negative for influenza. Overall VE was 46% (95% confidence interval [CI], 39–52). Adjusted VE against influenza A, influenza A(H1N1)pdm09, and influenza B was 63% (95% CI, 56–69), 77% (95% CI, 59–87), and 26% (95% CI, 14–36), respectively. Influenza vaccine was not effective against either influenza A or influenza B in infants 6 to 11 months of age. Two doses of influenza vaccine provided better protection against influenza A infection than a single dose did. VE against hospitalization influenza A infection was 76%. Influenza vaccine was effective against influenza A, especially against influenza A(H1N1)pdm09, but was much less effective against influenza B.  相似文献   
48.
Sugiyama Y  Kadota A 《Plant physiology》2011,155(3):1205-1213
Chloroplasts change their positions in the cell depending on the light conditions. In the dark, chloroplasts in fern prothallia locate along the anticlinal wall (dark position). However, chloroplasts become relocated to the periclinal wall (light position) when the light shines perpendicularly to the prothallia. Red light is effective in inducing this relocation in Adiantum capillus-veneris, and neochrome1 (neo1) has been identified as the red light receptor regulating this movement. Nevertheless, we found here that chloroplasts in neo1 mutants still become relocated from the dark position to the light position under red light. We tested four neo1 mutant alleles (neo1-1, neo1-2, neo1-3, and neo1-4), and all of them showed the red-light-induced chloroplast relocation. Furthermore, chloroplast light positioning under red light occurred also in Pteris vittata, another fern species naturally lacking the neo1-dependent phenomenon. The light positioning of chloroplasts occurred independently of the direction of red light, a response different to that of the neo1-dependent movement. Photosynthesis inhibitors 3-(3,4 dichlorophenyl)-1,1-dimethylurea or 2,5-dibromo-3-isopropyl-6-methyl-p-benzoquinone blocked this movement. Addition of sucrose (Suc) or glucose to the culture medium induced migration of the chloroplasts to the periclinal wall in darkness. Furthermore, Suc could override the effects of 3-(3,4 dichlorophenyl)-1,1-dimethylurea. Interestingly, the same light positioning was evident for nuclei under red light in the neo1 mutant. The nuclear light positioning was also induced in darkness with the addition of Suc or glucose. These results indicate that photosynthesis-dependent nondirectional movement contributes to the light positioning of these organelles in addition to the neo1-dependent directional movement toward light.  相似文献   
49.
Previous studies showed that biotin enhanced glucose-induced insulin secretion. Changes in the cytosolic ATP/ADP ratio in the pancreatic islets participate in the regulation of insulin secretion by glucose. In the present study we investigated whether biotin regulates the cytosolic ATP/ADP ratio in glucose-stimulated islets. When islets were stimulated with glucose plus biotin, the ATP/ADP ratio increased to approximately 160% of the ATP/ADP ratio in islets stimulated with glucose alone. The rate of glucose oxidation, assessed by CO(2) production, was also about 2-fold higher in islets treated with biotin. These increasing effects of biotin were proportional to the effects seen in insulin secretion. There are no previous reports of vitamins, such as biotin, directly affecting ATP synthesis. Our data indicate that biotin enhances ATP synthesis in islets following the increased rate of substrate oxidation in mitochondria and that, as a consequence of these events, glucose-induced insulin release is reinforced by biotin.  相似文献   
50.
AimsWe investigated the effects of globin digest (GD) and its active ingredient Trp-Thr-Gln-Arg (WTQR) on galactosamine/lipopolysaccharide (GalN/LPS)-induced liver injury in imprinting control region (ICR) mice.Main methodsThe effects of WTQR and GD on the liver injury were examined by measuring the survival rate, serum aminotransferase activities, hepatic components, antioxidant enzyme activities, histopathological analysis, serum levels and hepatic gene expression of tumor necrosis factor-alpha (TNF-α), macrophage inflammatory protein-2 (MIP-2), and nitric oxide (NO) or inducible nitric oxide synthase (iNOS), and nuclear factor-kappa B (NF-κB) p65 content in GalN/LPS-treated ICR mice. RAW264 mouse macrophages were used to confirm the anti-inflammatory effects of WTQR and GD on the macrophages.Key findingsWTQR and GD increased the survival rate, suppressed the serum aminotransferase activities, serum levels and hepatic gene expression of TNF-α, MIP-2, and NO or iNOS, and nuclear NF-κB p65 content in GalN/LPS-treated mice; decreased the oxidized glutathione content, increased the superoxide dismutase activity, and decreased the histopathological grade values of the hepatocyte necrosis and lobular inflammation in GalN/LPS-injured liver; and suppressed the release levels and gene expression of TNF-α, MIP-2, and NO or iNOS, and nuclear NF-κB p65 content in LPS-stimulated RAW264 macrophages. WTQR and GD may improve the antioxidant defense system and inflammatory status in GalN/LPS-injured liver.SignificanceThese findings indicate that WTQR and GD have hepatoprotective effects on GalN/LPS-induced liver injury in ICR mice.  相似文献   
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