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LKB1 is a significant tumor suppressor and epigenetic regulator playing a vital role in different types of cancers. SHMT1 and GLDC are two critical genes of the epigenetic pathway influenced by LKB1. As epigenetic is the major cause of AML pathogenesis, this study aimed at investigating LKB1, SHMT1, and GLDC gene expression levels in acute myeloid leukemia patients. The present study was conducted on LKB1, SHMT1, and GLDC gene expression levels in 60 de novo AML samples and 30 normal controls using real-time RT-PCR. The results showed that LKB1 and SHMT1 have respectively a significantly lower (P < 0.05) and higher (P < 0.05) expression level than that of normal controls. Furthermore, the correlation between LKB1 with SHMT1 and GLDC was significant and positive (P value: 0.015, r: 0.299). Positive findings confirm that metabolic pathways alongside the LKB1 association drive the epigenetic axis and its substrate production. Therefore, it can be concluded that the newly-discovered pathway in the pathogenesis of this disease provides new insights into the design of therapeutic targets.  相似文献   
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In this study, a novel Mn(iii)–Schiff base complex was synthesized and characterized. The structure of this complex was determined to be a deformed octahedral coordination sphere by single-crystal X-ray diffraction analysis. The Mn(iii)–Schiff base complex was supported on silica-coated iron magnetic nanoparticles via axial coordination by one-step complex anchoring to produce a heterogenized nanocatalyst. After this, the complex was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), and powder X-ray diffraction (XRD). Moreover, atomic absorption spectroscopy was used to determine the amount of the loaded metal. The heterogenized nanocatalyst effectively catalyzed the oxidation of a broad range of sulfides and alkenes with H2O2 in the presence of a glassy carbon electrode, applying voltage to the reaction mixture. The results showed that the application of a potential to the reaction mixture could significantly decrease the reaction time when compared with the case of similar chemical oxidation reactions. In addition, an excellent value of turnover frequency (17 750 h−1) was achieved for the electrochemical oxidation of styrene. Moreover, the nanocatalyst showed good recoverability without significant loss of its activity within six successive runs in the electrochemical oxidation of methyl phenyl sulfide and cyclooctene. The electrochemical properties and stability of Fe3O4@SiO2-[MnL(OAc)] were investigated by cyclic voltammetry measurements and chronoamperometry technique.

A Mn–Schiff base complex supported on silica-coated iron magnetic nanoparticles was used for the electrochemical oxidation of sulfides and alkenes.  相似文献   
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Background and aimsThere is some promising evidence regarding the beneficial effect of coconut oil on cardiometabolic risk factors. This study aimed to assess the effects of virgin coconut oil (VCO) consumption on metabolic syndrome (MetS) components, as well as, asymmetric dimethylarginine (ADMA) in adults with MetS.Methods and resultsIn this randomized controlled trial, 48 subjects, aged 20–50 years, with MetS were allocated into two groups; the intervention group was given 30 ml of VCO per day to substitute the same amounts of fat in their usual diet for four weeks. The control group was advised to follow their usual diet. VCO consumption significantly reduced serum levels of triglyceride (TG) (P = 0.001), very low-density lipoprotein (VLDL) (P = 0.001), and fasting blood sugar (FBS) (P = 0.015) compared to the control group. The levels of high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and total cholesterol (TC) were significantly increased in the VCO group when compared to the control group (P = 0.001). Circulatory ADMA also increased in the VCO group compared to the control group (P = 0.003). No significant differences were observed in the LDL-C/HDL-C ratio, anthropometric parameters, and blood pressure measurements between the two groups at the end of the study (P > 0.05).ConclusionVCO consumption increased the values of HDL-C while reduced TG and FBS levels. Blood pressure and waist circumference did not change. However, levels of TC, LDL-C, and ADMA elevated by VCO consumption. Caution is warranted until the results of further studies become available to explain the long-term effects of VCO consumption.Registration numberIRCT20131125015536N11.  相似文献   
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The reason why RBE for cell killing fell to less than unity (1.0) with very high-LET heavy-ions ((40)Ar: 1,640 keV/microm; (56)Fe: 780, 1,200, 2,000 keV/microm) was explored by evaluating the fraction of non-hit cell (time-lapse observation) and cells undergoing interphase death (calculation based on our previous data). CHO cells were exposed to 4 Gy (30% survival dose) of Ar (1,640 keV/microm) or Fe-ions (2,000 keV/microm). About 20% of all cells were judged to be non-hit, and about 10% cells survived radiation damage. About 70% cells died after dividing at least once (reproductive death) or without dividing (interphase death). RBE for reproductive (RBE[R]) and interphase (RBE[I]) death showed a similar LET dependence with maximum around 200 keV/microm. In this LET region, at 30% survival level, about 10% non-survivors underwent interphase death. The corresponding value for very high-LET Fe-ions (2,000 keV/microm) was not particularly high (approximately 15%), whereas that for X-rays was less than 3%. However, reproductive death (67%) predominated over interphase death (33%) even in regard to rather severely damaged cells (1% survival level) after exposure to Fe-ions (2,000 keV/microm). These indicate that interphase death is a type of cell death characteristic for the cells exposed to high-LET radiation and is not caused by "cellular over kill effect". Both NHF37 (non-hit fraction at 37% survival) and inactivation cross-section for reproductive death (sigma[R]) began to increase when LET exceeded 100 keV/microm. The exclusion of non-hit fraction in the calculation of surviving fraction partially prevented the fall of RBE[R] when LET exceeded 200 keV/microm. On the other hand, the mean number of lethal damage per unit dose (NLD/Gy) showed the same LET-dependent pattern as RBE[R]. These suggest that the increase in non-hit fraction and sigma[R] with an increasing LET is caused by enhanced clustering of ionization and DNA damage which lowers the energy efficiency for producing damage and RBE.  相似文献   
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Purpose The dosimetric features of an unflattened 6-MV photon beam of an Elekta SL-25 linac was calculated by the Monte Carlo (MC) method. Material and methods The head of the Elekta SL-25 linac was simulated using the MCNP4C MC code. The accuracy of the model was evaluated using measured dosimetric features, including depth dose values and dose profiles in a water phantom. The flattening filter was then removed, and beam dosimetric properties were calculated by the MC method and compared with those of the flattened photon beam. Results Our results showed a significant (twofold) increase in the dose rate for all field sizes. Also, the photon beam spectra for an unflattened beam were softer, which led to a steeper reduction in depth doses. The decrease in the out-of-field dose and increase in the contamination electrons and a buildup region dose were the other consequences of removing the flattening filter. Conclusion Our study revealed that, for recent radiotherapy techniques, the use of multileaf collimators for beam shaping removing the flattening filter could offer some advantages, including an increased dose rate and decreased out-of-field dose.  相似文献   
7.
Development of all CD4 T lineages requires nuclear factor TOX   总被引:1,自引:0,他引:1  
CD8(+) cytotoxic and CD4(+) helper/inducer T cells develop from common thymocyte precursors that express both CD4 and CD8 molecules. Upon T cell receptor signaling, these cells initiate a differentiation program that includes complex changes in CD4 and CD8 expression, allowing identification of transitional intermediates in this developmental pathway. Little is known about regulation of these early transitions or their specific importance to CD4 and CD8 T cell development. Here, we show a severe block at the CD4(lo)CD8(lo) transitional stage of positive selection caused by loss of the nuclear HMG box protein TOX. As a result, CD4 lineage T cells, including regulatory T and CD1d-dependent natural killer T cells, fail to develop. In contrast, functional CD8(+) T cells develop in TOX-deficient mice. Our data suggest that TOX-dependent transition to the CD4(+)CD8(lo) stage is required for continued development of class II major histocompatibility complex-specific T cells, regardless of ultimate lineage fate.  相似文献   
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Objective

To provide a low-cost and simple model of culturally-appropriate and low cost facilities for improvement of physical activity for girls and their mothers through an after-school program and to determine the changes in anthropometric indexes after this trial.

Methods

This national study was conducted in 2006-2007 in 7 provinces with different socioeconomic situations in Iran. Female students who studied in the 7th through 10th grade and their mothers were selected by random cluster sampling. In each province, 24 sessions of after-school aerobic physical activity were held for 90 minutes, two days a week, and 3 months long at school sites in the afternoon.

Findings

The study comprised 410 participants (204 mothers and 206 daughters), with a mean age of 15.86±1.01 and 40.71±6.3 years in girls and their mothers, respectively. The results of the focus group discussions showed that in general, both mothers and daughters were satisfied from the program and found it feasible and successful. After the trial, the indexes of generalized and abdominal obesity improved significantly both in girls and in their mothers (P-value <0.0001 for weight, body mass index and waist circumference).

Conclusion

Our findings may provide a low-cost and simple effective model of motivation for physical activity with targeted interventions for girls and their mothers. We suggest that the success of this trial might be a result of bonding and accompaniment of mothers and daughters. Such model can be integrated in the existing health and education systems to increase the physical activity level.  相似文献   
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