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61.
Although fatigue is a common and distressing symptom in cancer survivors, the mechanism of fatigue is not fully understood. Therefore, this study aims to investigate the relation between the fatigue and mindfulness of breast cancer survivors using anxiety, depression, pain, loneliness, and sleep disturbance as mediators. Path analysis was performed to examine direct and indirect associations between mindfulness and fatigue. Participants were breast cancer survivors who visited a breast surgery department at a university hospital in Japan for hormonal therapy or regular check-ups after treatment. The questionnaire measured cancer-related-fatigue, mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance. Demographic and clinical characteristics were collected from medical records. Two-hundred and seventy-nine breast cancer survivors were registered, of which 259 answered the questionnaire. Ten respondents with incomplete questionnaire data were excluded, resulting in 249 participants for the analyses. Our final model fit the data well (goodness of fit index = .993; adjusted goodness of fit index = .966; comparative fit index = .999; root mean square error of approximation = .016). Mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance were related to fatigue, and mindfulness had the most influence on fatigue (β = − .52). Mindfulness affected fatigue not only directly but also indirectly through anxiety, depression, pain, loneliness, and sleep disturbance. The study model helps to explain the process by which mindfulness affects fatigue. Our results suggest that mindfulness has both direct and indirect effects on the fatigue of breast cancer survivors and that mindfulness can be used to more effectively reduce their fatigue. It also suggests that health care professionals should be aware of factors such as anxiety, depression, pain, loneliness, and sleep disturbance in their care for fatigue of breast cancer survivors. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN number. 000027720) on June 12, 2017.  相似文献   
62.
63.
Osmotic adjustment plays a fundamental role in water stress responses and growth in plants; however, the molecular mechanisms governing this process are not fully understood. Here, we demonstrated that the KUP potassium transporter family plays important roles in this process, under the control of abscisic acid (ABA) and auxin. We generated Arabidopsis thaliana multiple mutants for K+ uptake transporter 6 (KUP6), KUP8, KUP2/SHORT HYPOCOTYL3, and an ABA-responsive potassium efflux channel, guard cell outward rectifying K+ channel (GORK). The triple mutants, kup268 and kup68 gork, exhibited enhanced cell expansion, suggesting that these KUPs negatively regulate turgor-dependent growth. Potassium uptake experiments using 86radioactive rubidium ion (86Rb+) in the mutants indicated that these KUPs might be involved in potassium efflux in Arabidopsis roots. The mutants showed increased auxin responses and decreased sensitivity to an auxin inhibitor (1-N-naphthylphthalamic acid) and ABA in lateral root growth. During water deficit stress, kup68 gork impaired ABA-mediated stomatal closing, and kup268 and kup68 gork decreased survival of drought stress. The protein kinase SNF1-related protein kinases 2E (SRK2E), a key component of ABA signaling, interacted with and phosphorylated KUP6, suggesting that KUP functions are regulated directly via an ABA signaling complex. We propose that the KUP6 subfamily transporters act as key factors in osmotic adjustment by balancing potassium homeostasis in cell growth and drought stress responses.  相似文献   
64.
Treatment with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib and erlotinib, has achieved high clinical response rates in patients with non–small cell lung cancers (NSCLCs). However, over time, most tumors develop acquired resistance to EGFR-TKIs, which is associated with the secondary EGFR T790M resistance mutation in about half the cases. Currently there are no effective treatment options for patients with this resistance mutation. Here we identified two novel HLA-A*0201 (A2)-restricted T cell epitopes containing the mutated methionine residue of the EGFR T790M mutation, T790M-5 (MQLMPFGCLL) and T790M-7 (LIMQLMPFGCL), as potential targets for EGFR-TKI-resistant patients. When peripheral blood cells were repeatedly stimulated in vitro with these two peptides and assessed by antigen-specific IFN-γ secretion, T cell lines responsive to T790M-5 and T790M-7 were established in 5 of 6 (83%) and 3 of 6 (50%) healthy donors, respectively. Additionally, the T790M-5- and T790M-7-specific T cell lines displayed an MHC class I-restricted reactivity against NSCLC cell lines expressing both HLA-A2 and the T790M mutation. Interestingly, the NSCLC patients with antigen-specific T cell responses to these epitopes showed a significantly less frequency of EGFR-T790M mutation than those without them [1 of 7 (14%) vs 9 of 15 (60%); chi-squared test, p  =  0.0449], indicating the negative correlation between the immune responses to the EGFR-T790M-derived epitopes and the presence of EGFR-T790M mutation in NSCLC patients. This finding could possibly be explained by the hypothesis that immune responses to the mutated neo-antigens derived from T790M might prevent the emergence of tumor cell variants with the T790M resistance mutation in NSCLC patients during EGFR-TKI treatment. Together, our results suggest that the identified T cell epitopes might provide a novel immunotherapeutic approach for prevention and/or treatment of EGFR-TKI resistance with the secondary EGFR T790M resistance mutation in NSCLC patients.  相似文献   
65.
Artificial induction of active DNA demethylation appears to be a possible and useful strategy in molecular biology research and therapy development. Dimethyl sulfoxide (DMSO) was shown to cause phenotypic changes in embryonic stem cells altering the genome-wide DNA methylation profiles. Here we report that DMSO increases global and gene-specific DNA hydroxymethylation levels in pre-osteoblastic MC3T3-E1 cells. After 1 day, DMSO increased the expression of genes involved in DNA hydroxymethylation (TET) and nucleotide excision repair (GADD45) and decreased the expression of genes related to DNA methylation (Dnmt1, Dnmt3b, Hells). Already 12 hours after seeding, before first replication, DMSO increased the expression of the pro-apoptotic gene Fas and of the early osteoblastic factor Dlx5, which proved to be Tet1 dependent. At this time an increase of 5-methyl-cytosine hydroxylation (5-hmC) with a concomitant loss of methyl-cytosines on Fas and Dlx5 promoters as well as an increase in global 5-hmC and loss in global DNA methylation was observed. Time course-staining of nuclei suggested euchromatic localization of DMSO induced 5-hmC. As consequence of induced Fas expression, caspase 3/7 and 8 activities were increased indicating apoptosis. After 5 days, the effect of DMSO on promoter- and global methylation as well as on gene expression of Fas and Dlx5 and on caspases activities was reduced or reversed indicating down-regulation of apoptosis. At this time, up regulation of genes important for matrix synthesis suggests that DMSO via hydroxymethylation of the Fas promoter initially stimulates apoptosis in a subpopulation of the heterogeneous MC3T3-E1 cell line, leaving a cell population of extra-cellular matrix producing osteoblasts.  相似文献   
66.
Abstract

A simple classical model is used for the study of the structural transformations of ice under high pressures, such as ice VIII to VII and X, via classical molecular dynamics (MD) simulation. In the present MD simulation, pair potentials of a simple form between pair of atoms and a thee-body potential representing the H-O-H angle dependence, originally developed by Kawamura et al., were used. Starting with a stable ice VIII at low pressure and low temperature, we have carried out two different MD runs, one with increasing pressure keeping the temperature constant (simulation I) and the other with increasing temperature under constant pressure (simulation II). From these MD simulations we have obtained the structural transformations from ice VIII to VII for both simulations; the former was finally transformed into ice X for the simulation I. The present results are compatible with recent experiments on high pressure ices.  相似文献   
67.
The effect of insulin-like growth factor-1 (IGF-1) on the behavior of rabbit chondrocytes in cultured collagen (CL) gels initially seeded with 2 × 105 cells/ml was examined. On day 5, the frequency of migrating cells cultured in presence of 100 ng IGF-1/ml was 0.04, which was 54 % of the frequency in IGF-1-free culture. The presence of IGF-1 caused an increase in the frequency of dividing cells from 0.09 to 0.13. These results suggest that IGF-1 suppressed the migration of chondrocytes in the CL gels while stimulating cell division in the initial culture phase. The proteolytic migration of cells was thought to be suppressed by the down-regulation of membrane type 1 matrix metalloproteinase by IGF-1. This contributed to the formation of aggregates with spherical-shaped cells that produced collagen type II.  相似文献   
68.
Human acidic mammalian chitinase (hAMCase) was recently shown to be involved in the development of asthma, suggesting a possible application for hAMCase inhibitors as novel therapeutic agents for asthma. We therefore initiated drug discovery research into hAMCase using a combination of in silico methodologies and a hAMCase assay system. We first selected 23 candidate hAMCase inhibitors from a database of four million compounds using a multistep screening system combining Tripos Topomer Search technology, a docking calculation and two-dimensional molecular similarity analysis. We then measured hAMCase inhibitory activity of the selected compounds and identified seven compounds with IC50 values ?100 μM. A model describing the binding modes of these hit compounds to hAMCase was constructed, and we discuss the structure–activity relationships of the compounds we identified, suggested by the model and the actual inhibitory activities of the compounds.  相似文献   
69.
An enzyme which catalyzes the degradation of polyvinyl alcohol) (PVA) oxidized by secondary alcohol oxidase, in which hydroxyl groups of PVA are partially converted to carbonyl groups, has been purified from a fraction adsorbed on DEAE-Sephadex at pH 7.0 from PVA-degrading enzyme activities produced by a bacterial symbiotic mixed culture in a minimal medium containing PVA as a sole source of carbon and energy. The purified enzyme was electrophoretically homogeneous in the absence and presence of SDS.

The enzyme is a single polypeptide with a molecular weight of about 36,000 and has an isoelectric point of 5.1. The N- and C-terminal amino acid residues are both alanine. The enzyme is most active at pH 6.5 and at 40°C and is stable between pH 6.0 and 9.0 and at temperatures below 45°C. The enzyme is inhibited by Hg2+ and is restored by the addition of reduced glutathione, although p-chloromercuribenzoate has no effect.

The enzyme was active on oxidized PVA, but not on PVA and on various low molecular weight carbonyl compounds examined. The enzyme reaction on oxidized PVA resulted in a rapid decrease in viscosity, a fall of pH, and production of carboxylic acids. The enzyme, therefore, is considered to be an oxidized PVA hydrolase.

The enzyme shows a common antigenicity in immunodiffusion and neutralization reactions with antisera to an oxidized PVA hydrolase previously purified from another fraction adsorbed on SP-Sephadex at pH 7.0 from the PVA-degrading enzyme activities [Agric. Biol. Chem., 45, 63 (1981)]. The relations between these two oxidized PVA hydrolases are discussed.  相似文献   
70.
Shiromodiol-diacetate, shiromool, and shiromodiol-monoacetate are insect feeding inhibitors isolated from Parabenzoin trilobum Nakai. On the bases of chemical and spectral evidence we deduced that these compounds have the structure shown in I, XVIII, and XI, respectively.  相似文献   
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