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71.
Molecular and Cellular Biochemistry - Glioma, as one of the most severe human malignancies, is defined as the Central Nervous System’s (CNS) tumors. Glioblastoma (GBM) in this regard, is the...  相似文献   
72.
Contradictory results were reported on the effect of fat mass- and obesity-associated (FTO) gene and anthropometric measurements on breast cancer (BC). This study aimed to assess the interactions between rs9939609 polymorphism of FTO gene, anthropometric indices and BC risk in Iranian women. This case-control study was performed on 540 women including 180 women with BC and 360 healthy women in Tehran, Iran. Physical activity and dietary intakes were assessed by validated questionnaires. Data on sociodemographic and pathologic factors of the participants as well as their blood samples were collected. The rs9939609 FTO gene polymorphism was genotyped using the tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR). No significant association was found between BC and risk allele of FTO rs9939609 polymorphism after adjustments for the confounders. However, there was a significant association between rs9939609 polymorphism risk allele and BC risk in females with overweight, even after adjusting for age, family history of BC, abortion, BMI and the number of pregnancies (P < .05). The association was disappeared after further adjustments for lifestyle factors including smoking, alcohol consumption, calorie and macronutrients intake, and physical activity. The FTO gene polymorphism was associated with the risk of BC in overweight individuals. This association was influenced by environmental factors including diet, alcohol consumption and smoking. Future studies are required to confirm the association between the FTO gene and BC in overweight females and to identify the underlying mechanisms.  相似文献   
73.
A novel series of hybrid arylisoxazole‐chromenone carboxamides were designed, synthesized, and evaluated for their cholinesterase (ChE) inhibitory activity based on the modified Ellman's method. Among synthesized compounds, 5‐(3‐nitrophenyl)‐N‐{4‐[(2‐oxo‐2H‐1‐benzopyran‐7‐yl)oxy]phenyl}‐1,2‐oxazole‐3‐carboxamide depicted the most acetylcholinesterase (AChE) inhibitory activity (IC50=1.23 μm ) and 5‐(3‐chlorophenyl)‐N‐{4‐[(2‐oxo‐2H‐1‐benzopyran‐7‐yl)oxy]phenyl}‐1,2‐oxazole‐3‐carboxamide was found to be the most potent butyrylcholinesterase (BChE) inhibitor (IC50=9.71 μm ). 5‐(3‐Nitrophenyl)‐N‐{4‐[(2‐oxo‐2H‐1‐benzopyran‐7‐yl)oxy]phenyl}‐1,2‐oxazole‐3‐carboxamide was further investigated for its BACE1 inhibitory activity as well as neuroprotectivity and metal chelating ability as important factors involved in onset and progress of Alzheimer's disease. It could inhibit BACE1 by 48.46 % at 50 μm . It also showed 6.4 % protection at 25 μm and satisfactory chelating ability toward Zn2+, Fe2+, and Cu2+ ions. Docking studies of 5‐(3‐nitrophenyl)‐N‐{4‐[(2‐oxo‐2H‐1‐benzopyran‐7‐yl)oxy]phenyl}‐1,2‐oxazole‐3‐carboxamide and 5‐(3‐chlorophenyl)‐N‐{4‐[(2‐oxo‐2H‐1‐benzopyran‐7‐yl)oxy]phenyl}‐1,2‐oxazole‐3‐carboxamide confirmed desired interactions with those amino acid residues of the AChE and BChE, respectively.  相似文献   
74.

Synbiotic (probiotic bacteria and prebiotic) has beneficial effects on the gastrointestinal tract. This study was designed to investigate the effect of synbiotic supplementation on the growth of mild to moderate failure to thrive (FTT) children. A randomized, triple-blind, placebo-controlled trial was conducted involving 80 children aged 2–5 years with mild to moderate FTT, who were assigned at random to receive synbiotic supplementation (109 colony-forming units) or placebo for 30 days. The weights, height, and BMI were recorded in a structured diary, and the questionnaires were completed to monitor the numbers of infection episodes, gastrointestinal problems, admission to hospital, and appetite improvement during the study. Sixty-nine children completed the study. There were no differences in the demographic characteristic between the two groups. The mean weight was similar at baseline. After 30 days of intervention, the mean weight of the participants in the synbiotic group increased significantly than those in the placebo group (600?±?37 vs. 74?±?32 g/month P 0.000). BMI changes in synbiotic and placebo group were 0.44 and 0.07 kg/m2, and that the differences among the two groups were significant.(P 0.045) Furthermore, the height increment in synbiotic and placebo group was 0.41 and 0.37 cm respectively with no significant difference (P 0.761). Administration of 30-day synbiotic supplementation may significantly improve weight and BMI in Iranian children with mild to moderate FTT, but there is no effect on the height in this study. Further studies should be designed to found out the effect of synbiotic on growth parameters in undernourished and well-nourished children.

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75.
Canonical Monte Carlo (CMC) simulations were carried out to investigate the behavior of CO2 and N2 mixtures upon adsorption on single walled carbon nanotubes (CNTs). In the simulation, all the particle–particle interactions between CO2, N and C were modeled using Lennard-Jones (LJ) potential. To provide deep insight into the effect of pore width, temperature, pressure and bulk composition on the adsorption behavior of CO2 /N2 mixtures, five different CNTs [(6,6), (7,7), (8,8) (9,9) and (10,10) CNT] with diameters ranging from 0.807 to 1.35 nm, three temperatures (300 323 and 343 K), six pressures (0.15, 2, 4, 6, 8 and 10 MPa), and three bulk mole compositions of carbon dioxide (0.3 0.5 and 0.7) were tested. The results from all the simulation conditions investigated in this work show that CNTs preferentially adsorb carbon dioxide relative to nitrogen in a binary mixture. The results are consistent with the hypothesis that stronger interaction of one component with the nanotube surface results in a higher adsorption capacity compared to the other component. An optimized pore size of D = 8.07 nm corresponding to (6, 6) CNT, at T = 300 K and P = 0.15 MPa at a bulk mole composition of yCO2 =0.3 was identified in which carbon nanotubes demonstrate the greatest selectivity for separation of carbon dioxide relative to nitrogen. In addition, it is worth pointing out that, under similar simulation conditions, CNTs exhibit higher selectivity compared to other carbon-based materials [carbon membrane polyimide (PI) and PI/multi-wall carbon nanotubes (MWCNTs)] for CO2 adsorption. As a prototype, the selectivity of an equimolar mixture of CO2 /N2 for adsorption on (6, 6) CNTs at 300 K and 0.15 MPa reaches 9.68, which is considerably larger than that reported in carbon membrane. Therefore, it can be concluded that carbon nanotubes can act as a capable adsorbent for adsorption/desorption of CO2 in comparison with other carbon-based materials in the literature.  相似文献   
76.
Changes in the copper (Cu) and zinc (Zn) concentrations have been reported previously in ischemic cardiomyopathy (ISCMP). Due to controversial results, the aims of this study were to compare levels of Cu, Zn, and Zn/Cu ratio of ISCMP patients with healthy volunteers and also to investigate the possible relationship between trace elements status in ISCMP patients with the severity of clinical disease based on the New York Heart Association (NYHA) classification. The subjects of this study consisted of 30 ISCMP and 27 healthy volunteers. ISCMP was diagnosed with a history of previous myocardial infarction and also coronary artery disease was confirmed by coronary angiography. Exclusion criteria were renal or hepatic insufficiency, alcohol usage, and intake of supplements containing Cu or Zn within 1 week. Cu and Zn levels have been assayed with atomic absorption spectrophotometry. Statistical analysis was performed with the SPSS 10 software using independent sample t test for comparing the levels of Cu and Zn between ISCMP and normal subjects. The mean Cu level of the ISCMP group (1.54 ± 0.52 mg/L) was significantly more than the Cu levels of the healthy volunteers (1.31 ± 0.24 mg/L; p = 0.048). The mean Zn levels of the ISCMP and healthy volunteers were 1.05 ± 0.28 and 1.12 ± 0.42, respectively, without any significant difference between groups. There was a trend for higher Cu level, lower Zn level, and lower Zn/Cu ratio in NYHA III patients in comparison with NYHA II group. Considering the results of this study, Cu may have a role in the development of ISCMP. Interventions such as administration of Cu chelators to relieve the symptoms or to decrease the progression of ISCMP is needed to be examined in large clinical trials. In this study, the Zn level of ISCMP patients was not significantly different in comparison with the healthy volunteers.  相似文献   
77.
This study was carried out to assess the dissipation of 17 selected polychlorinated biphenyl (PCBi) congeners in a transformer oil-contaminated soil using bioaugmentation with 2 PCB-degrading bacterial strains, i.e., Pseudomonas spp. S5 and Alcaligenes faecalis, assisted or not by the maize (Zea mays L.) plantation. After 5 and 10 weeks of treatment, the remaining concentrations of the target PCBi congeners in the soil were extracted and measured using GC-MS. Results showed that the bacterial augmentation treatments with Pseudomonas spp. S5 and A. faecalis led to 21.4% and 20.4% reduction in the total concentration of the target PCBs (ΣPCBi), respectively, compared to non-bioaugmented unplanted control soil. The ΣPCBi decreased by 35.8% in the non-bioaugmented planted soil compared with the control. The greatest degradation of the PCB congeners was observed over a 10-week period in the soil inoculated with Pseudomonas spp. S5 and cultivated with maize. Under this treatment, the ΣPCBi decreased from 357 to 119 ng g?1 (66.7% lower) and from 1091 to 520 ng g?1 (52.3% lower). Overall, the results suggested that the combined application of phytoremediation and bioaugmentation was an effective technique to remove PCBs and remediate transformer oil-contaminated soils.  相似文献   
78.
Chimeric antigen receptor (CAR) T-cell therapy is an immunotherapy approach that has played a tremendous role in the battle against cancer for years. Since the CAR T lymphocytes are unrestricted-major histocompatibility complex T lymphocytes, they could identify more targets than natural T cells, resulting in practical and widespread functions. The good prospects of CAR T-cell therapy in oncology can be additionally applied to treat other diseases such as autoimmune and infectious diseases. CAR-T cell-derived immunotherapy for autoimmune disorders can be allocated to CAR-Tregs and chimeric autoantibody receptor T cells. Other generations of CARs target human immunodeficiency virus (HIV) proteins. In this review, we summarize CAR-T cell therapies in autoimmune disorders and HIV infection.  相似文献   
79.
The relative contributions of natural and anthropogenic fluctuations are different in shaping habitat health status and natural benthic communities in tropical coastal water. Understanding responses of coastal benthic communities to these fluctuations are still equivocal and thus available data are inadequate. Here, multiple analytical approaches were used to address the significant risk factors and their impacts on coastal benthic habitat health through space and time. A total abundance of 1436 ± 612 individuals of 33 benthic species were counted and identified from 22 sampling stations across eight sampling periods over the two years of study. Bioassay results showed that the benthic community is moderately exposed to anthropogenic pollutants in Klang Strait coastal water. The results showed that there were no significant temporal changes of habitat health status and macrobenthic community structure; however, spatial changes were significant and synchronized with anthropogenic and natural fluctuations. This study demonstrates that Cd and Hg levels and sediment characteristics played the primary role in shaping the habitat health and macrobenthic assemblages, whereas the influence of other factors were insignificant.  相似文献   
80.

Aim

Evaluation of application of EPID for rapid QC testing of linear accelerator.

Background

Quality control of a linear accelerator device is a time and energy intensive process. In this study, attempts have been made to perform the linear accelerator quality control using electronic portal imaging device (EPID), which is mounted on most accelerators.

Materials and methods

First, quality control and dosimetry parameters of the device were determined and measured based on standard protocols to ensure full calibration of the accelerator. Then, various features of EPID including spatial resolution and contrast resolution, the effect of buildup region, dose response and image uniformity were evaluated. In the next step, consistent with the parameters of linear accelerator quality control including field size, field flatness and symmetry, the light field coincidence with X-ray field, mechanical stability and multileaf collimator position accuracy test, the output images of device were obtained.After feeding images to the MATLAB software, their pixel content was analyzed. All measurements of the three photon beams were repeated three times.

Results

The EPID image had a desirable resolution, contrast and uniformity and displayed high sensitivity to dose changes with linear dose response. Seven qualitative parameters of the linear accelerator were then controlled by EPID.

Conclusions

The results of the linear accelerator quality control using the EPID were consistent with practice. Quality control using the EPID was more convenient and faster than conventional methods.  相似文献   
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