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91.
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Inflammation Research - Coronavirus disease 2019 (COVID-19) pandemic is still a world-class challenge. Inflammation, especially its severe form with excess release of pro-inflammatory cytokines...  相似文献   
93.

Background

Umbelliprenin is a natural compound, belonging to the class of sesquiterpene coumarins. Recently, umbelliprenin has attracted the researchers'' attention for its antitumor activities against skin tumors. Its effect on lung cancer is largely unknown. The aim of our study was to investigate the effects of this natural compound, which is expected to have low adverse effects, on lung cancer.

Methods

The QU-DB large cell and A549 adenocarcinoma lung cancer cell lines were treated with umbelliprenin. IC50 values were estimated using methyl thiazolely diphenyl-tetrazolium bromide (MTT) assay, in which a decrease in MTT reduction can occur as a result of cell death or cell proliferation inhibition. To quantify the rate of cell death at IC50 values, flow cytometry using Annexin V-FITC (for apoptotic cells), and propidium iodide (for necrotic cells) dyes were employed.

Results

Data from three independent MTT experiments in triplicate revealed that IC50 values for QU-DB and A549 were 47 ± 5.3 μM and 52 ± 1.97 μM, respectively. Annexin V/PI staining demonstrated that umbelliprenin treatment at IC50 induced 50% cell death in QU-DB cells, but produced no significant death in A549 cells until increasing the umbelliprenin concentration to IC80. The pattern of cell death was predominantly apoptosis in both cell lines. When peripheral blood mononuclear cells were treated with 50 μM and less concentrations of umbelliprenin, no suppressive effect was observed.

Conclusions

We found cytotoxic/anti-proliferative effects of umbelliprenin against two different types of lung cancer cell lines.  相似文献   
94.
A number of studies have suggested that environmental contamination with organochlorine pesticides may be related to risk of breast cancer. To investigate this association in a rural part of Australia, organochlorine contamination data from a breast milk organochlorine study conducted in the state of Victoria in 1993 were used. The state was divided into 11 statistical divisions. Standardized incidence ratios (SIRs) for the 11 regions were calculated using breast cancer incidence data from 1983 to 2002. During that time, 47,250 breast cancer cases occurred in Victoria, which had an average population of 2,147,409 women. The Ovens-Murray region, which was the region most contaminated with organochlorine pesticides, showed an elevated SIR of 1.10 (95%CI, 1.03–1.17), although two other regions with lower organochlorine contamination levels also had elevated SIRs. The rural part of the Ovens-Murray region, where the main pesticide use occurred, had the highest SIR, 1.15 (95%CI, 1.07–1.23). We did not find any significant correlation between organochlorine contamination and the age-standardized rate of breast cancer across all regions. But a positive dose-response relationship using an adjusted negative binomial model was detected for heptachlor epoxide. Our study may provide limited support for the role of environmental contamination with organochlorine pesticides in the development of breast cancer.  相似文献   
95.
The Groucho/Tle family of corepressor proteins is known to regulate multiple developmental pathways. Applying the dominant-negative effect of the short member Aes, we demonstrate here a critical role of this gene family also for ear development. Misexpression of Aes in medaka embryos resulted in reduced size or loss of otic vesicles, whereas overexpression of the full-length Groucho protein Tle4 gave the opposite phenotype. These results are in close agreement with phenotypes observed for eye formation, suggesting a similar role for Groucho/Tle proteins in the developmental pathways of both sensory organs. Furthermore, by using the heat-inducible HSE promoter, we observed reversible branching of the embryonic axis upon Aes misexpression, indicating a transient duplication of the organizer. Groucho proteins, therefore, are critical for organizer maintenance.  相似文献   
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In this work, the photocatalytic efficiency of Cu(ii)–vitamin C complex immobilized on titanium dioxide nanoparticles was exploited in the photo-assisted homocoupling reaction of aryl boronic acids under heterogeneous conditions. The homocoupling reaction affords the corresponding symmetrical biaryls in 50–97% yields at ambient temperature in the air under visible light irradiation without any need for any additive such as base or oxidant. This method tolerates various substituents on the aryl boronic acids such as halogen, carbonyl, and a nitro group. The light-dependent photocatalytic performance of the title catalyst evaluated by action spectra revealed a maximum apparent quantum efficiency (AQYs) at 410 nm demonstrating the visible-light-driven photocatalytic reaction. The as-prepared nano biophotocatalyst proved to be reusable at least six times without losing its activity. Thus this work exhibits a favorable method from the environmental and economic point of view which enables the industrially important reactions such as coupling reactions, to be carried out efficiently under photocatalytic and practically attainable conditions.

TiO2–ascorbic acid (AA)–Cu(ii), nanohybrid is active in the selective aerobic oxidative homocoupling of aryl boronic acids under heterogeneous conditions in air and visible light conditions.  相似文献   
100.

Background

The use of valid and reliable outcome rating scales is essential for evaluating the result of different treatments and interventions. The purposes of this study were to translate and culturally adapt the American Orthopaedic Foot and Ankle Society ankle–hindfoot scale (AOFAS-AHFS) into Persian languages and evaluate its psychometric properties.

Methods

Forward–backward translation and cultural adaptation method were used to develop Persian version of AOFAS-AHFS. From March to July 2016, one hundred consecutive patients with ankle and hindfoot injuries were included. Internal consistency and reproducibility were evaluated using Cronbach’s alpha, Spearman’s rank correlation coefficient and Intraclass correlation coefficient (ICC) respectively. Construct validity reported which compare the outcome rating scale measurements with Short Form-36 (SF-36), also convergent and discriminant validity evaluated using Spearman’s rank correlation coefficient.

Results

Mean age (SD) of the patients was 41.95 ± 13.45 years. Cronbach’s α coefficient, Spearman’s rho and ICC values were 0.71, 0.89 and 0.90 respectively. Total score of AOFAS-AHFS and SF-36 domains has a correlation ranged between 0.17–0.55. Spearman’s rank correlation coefficient of 0.4 was exceeded by all items with the exception of stability. The Spearman’s rank correlation between each item in functional subscales with its own subscales was higher than the correlation between these items and other subscales.

Conclusions

Persian version of AOFAS-AHFS provides additional reliable and valid instrument which can be used to assess broad range of patients with foot and ankle disorders that speaking in Persian. However, it seems that the original version of AOFAS-AHFS needs some revisions.  相似文献   
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