Epithelial-mesenchymal transition (EMT)-associated proteins play key roles in cancer progression and metastasis with the involvement of microRNAs (miRNAs). This study aims to assess the role of ...miR-506 working in tandem with LIM Homeobox 2 (LHX2) in EMT and metastasis through the Wnt/β-catenin signaling pathway in nasopharyngeal carcinoma (NPC).
Differentially expressed genes associated with NPC were screened using microarray analyses, from which LHX2 was identified. Next, the potential relationship between miR-506 and LHX2 was analyzed. In order to explore the effect of miR-506 or LHX2 on NPC cell proliferation, migration, invasion and apoptosis, serials of mimics, inhibitors or siRNA against LHX2 were transfected into NPC cells. Then, the expression patterns of LHX2, Wnt1, β-catenin, E-cadherin, Vimentin, TCF4 and Twist were determined to assess the influence of miR-506 or LHX2 on EMT as well as the relationship between the Wnt/β-catenin signaling pathway and TCF4. The tumorigenicity and lymph node metastasis (LNM) in xenograft tumors of nude mice were observed.
The has-miR-506-3p was identified as the down-regulated gene in NPC based on the microarray data while LHX2 was negatively regulated by miR-506. Over-expression of miR-506 or silencing of LHK2 inhibited NPC cell proliferation, migration, invasion, tumorigenicity and LNM but promoted apoptosis indicated by decreased Wnt1, β-catenin, Vimentin, TCF4 and Twist expressions along with increased E-cadherin expressions.
miR-506 inhibits tumor growth and metastasis in NPC via inhibition of Wnt/β-catenin signaling by down-regulating LHX2, accompanied by decreased TCF4. Taken together, miR-506 targeted-inhibition LHX2 presents a promising therapeutic strategy for the treatment of NPC.
ChiCTR1800018889 . Registered 15 October 2018.
Background: Motivation matters in medical students' academic performance. However, few studies have specifically examined how motivation and external environmental factors (e.g., institutions) affect ...medical students' performance with large-scale data sets. The roles of self-efficacy and learning engagement in the mechanisms that govern how motivation affects academic performance are still unclear.
Objective: This study aims to advance a comprehensive understanding about the relationships between medical students' motivation, self-efficacy, learning engagement, and academic performance in a nationwide survey, taking students' demographic factors and sociocultural environments into consideration.
Design: We collected data from 1930 medical students in China. We probed the relations between studying variables. We then performed structural equation model (SEM) analysis to examine the mediating roles of self-efficacy and learning engagement on the relationship between motivation and academic performance. We further carried out multiple-group SEM analyses to compare differences between males and females, and between students in key universities and colleges (KUCs) and non-key universities and colleges (NKUCs).
Results: Medical students in KUCs demonstrated significantly higher intrinsic motivation, better academic performance and lower extrinsic motivation than those in NKUCs. Male students reported higher intrinsic motivation but surprisingly lower academic performance than females. The total effect of intrinsic motivation on academic performance was larger than that of extrinsic motivation. There were significant indirect effects of either intrinsic or extrinsic motivation on academic performance through learning engagement. Besides, both intrinsic motivation and extrinsic motivation predicted self-efficacy; however, the direct effect of self-efficacy on academic performance was not significant.
Conclusions: This study provided researchers with a holistic picture of students' types of motivation in relation to academic performance. Findings from this study can help in rethinking the role of self-efficacy in medicine, in finding more effective interventions for promoting medical students' levels of motivation, and in developing motivation-related counselling methods for different groups of medical students.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The total cross section of the process μ−μ+→νμν¯μtt¯H has strong dependence on the CP phase ξ of the top Yukawa coupling, where the ratio of ξ=π and ξ=0 (SM) grows to 670 at s=30 TeV, 3400 at 100 ...TeV. We study the cause of the strong energy dependence and identify its origin as the (E/mW)2 growth of the weak boson fusion sub-amplitudes, WL−WL+→tt¯H, with the two W's are longitudinally polarized. We repeat the study in the SMEFT framework where EW gauge invariance is manifest and find that the highest energy cross section is reduced to a quarter of the complex top Yukawa model result, with the same energy power. By applying the Goldstone boson (GB) equivalence theorem, we identify the origin of this strong energy growth of the SMEFT amplitudes as associated with the dimension-6 π−π+ttH vertex, where π± denotes the GB of W±. We obtain the unitarity bound on the coefficient of the SMEFT operator by studying all 2→2 and 2→3 cross sections in the J=0 channel.
A chiral aluminum complex controlled, enantioselective nickel‐catalyzed domino reaction of aryl nitriles and alkynes proceeding by C−CN bond activation was developed. The reaction provides various ...indenes, bearing chiral all‐carbon quaternary centers, under mild reaction conditions in yields of 32 to 91 % and ee values within the 73–98 % range. The reaction mechanism and aspects of stereocontrol were investigated by DFT calculations.
Al takes control: A chiral aluminum complex controlled, enantioselective nickel‐catalyzed domino reaction of aryl nitriles and alkynes proceeding by C−CN bond activation was developed. The reaction provides various indenes, bearing chiral all‐carbon quaternary centers, under mild reaction conditions in good yields and with good ee values. The reaction mechanism and aspects of stereocontrol were investigated by DFT calculations.
A
bstract
We study consequences of CP violation in the
h
t
t
¯
Yukawa coupling through the process
e
+
e
−
→
h
125
t
t
¯
. The helicity amplitudes are calculated in the
t
t
¯
rest frame, where the ...initial
e
+
e
−
current and the final Higgs boson have the same three-momentum. CP-violating asymmetries appear not only in the azimuthal angle between the
e
+
e
−
plane and the
t
t
¯
plane about the Higgs momentum direction, but also in the correlated decay angular distributions of
t
and
t
¯
. Complete description of the production and decay angular distributions are obtained analytically, including both leptonic and hadronic decays of
t
and
t
¯
. We study the ultimate sensitivity to the CP-violating
h
t
t
¯
coupling at a few center-of-mass energies. Our analysis shows that the possibility of discovering CP-violating
h
t
t
¯
coupling improves significantly by studying
t
t
¯
decay angular correlations, and more importantly, by increasing its energy upgrade target from
s
=
500
GeV to 550 GeV.
Cisplatin-based chemotherapeutic regimens are the most frequently used adjuvant treatments for many types of cancer. However, the development of chemoresistance to cisplatin results in treatment ...failure. Despite the significant developments in understanding the mechanisms of cisplatin resistance, effective strategies to enhance the chemosensitivity of cisplatin are lacking. Phytochemicals are naturally occurring plant-based compounds that can augment the anti-cancer activity of cisplatin, with minimal side effects. Notably, some novel phytochemicals, such as curcumin, not only increase the efficacy of cisplatin but also decrease toxicity induced by cisplatin. However, the exact mechanisms underlying this process remain unclear. In this review, we discussed the progress made in utilizing phytochemicals to enhance the anti-cancer efficacy of cisplatin. We also presented some ideal phytochemicals as novel agents for counteracting cisplatin-induced organ damage.
Ribosomal deficits are documented in mild cognitive impairment (MCI), which often represents an early stage Alzheimer's disease (AD), as well as in advanced AD. The nucleolar rRNA genes (rDNA), ...transcription of which is critical for ribosomal biogenesis, are regulated by epigenetic silencing including promoter CpG methylation.
To assess whether CpG methylation of the rDNA promoter was dysregulated across the AD spectrum, we analyzed brain samples from 10 MCI-, 23 AD-, and, 24 age-matched control individuals using bisulfite mapping. The rDNA promoter became hypermethylated in cerebro-cortical samples from MCI and AD groups. In parietal cortex, the rDNA promoter was hypermethylated more in MCI than in advanced AD. The cytosine methylation of total genomic DNA was similar in AD, MCI, and control samples. Consistent with a notion that hypermethylation-mediated silencing of the nucleolar chromatin stabilizes rDNA loci, preventing their senescence-associated loss, genomic rDNA content was elevated in cerebrocortical samples from MCI and AD groups.
In conclusion, rDNA hypermethylation could be a new epigenetic marker of AD. Moreover, silencing of nucleolar chromatin may occur during early stages of AD pathology and play a role in AD-related ribosomal deficits and, ultimately, dementia.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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•The intrinsic or acquired resistance to cisplatin remains a major obstacle for cancer therapy.•STAT3 is important for mediating drug resistance in cancer treatment.•STAT3 inhibitors ...have the ability to enhance the anti-tumor efficacy of cisplatin.
Cisplatin is one of the most frequently used chemotherapeutic agents for treatment of a wide range of cancer types. Nevertheless, the intrinsic or acquired resistance to cisplatin remains a major obstacle for cancer therapy. There are a number of factors contributing to the onset of this phenotype resistance. Signal transducers and activators of transcription 3 (STAT3) is constitutively activated in many cancer types, and such hyperactivation is associated with a poor clinical prognosis. In addition, STAT3 inhibitors have shown the ability to enhance the anti-tumor efficacy of cisplatin. In this review, we summarized the current knowledge of the STAT3 pathway in cancer treatment and its contribution to cisplatin resistance. Moreover, this review focuses on targeting STAT3 inhibition to overcome cisplatin resistance.
Enrichments of emerging pollutants and drugs from various samples with complex matrices make it urgent and challenging to develop novel SPME coatings, and the flourishing materials with high ...enrichment capabilities provide good opportunities for it. This review summarizes the used materials for the fabrication of SPME coatings in the past five years, including carbon, polymer, metal organic frameworks (MOFs), covalent organic frameworks (COFs), ionic liquids (ILs), metal/metal oxide nanoparticles and silica. To obtain SPME coatings with excellent physical performance, anti-interference ability and high enrichment capability, suitable coating methods and supports are selected according to the properties of coating materials. In addition, the factors of coating materials and analytes influencing the enrichment effect are summarized and illustrated preliminarily, benefiting for further design of advanced coating materials with enhanced performance.
•A variety of new materials employed as novel fiber coatings have been summarized.•The coating methods have been reviewed according to the property of selected material.•The enrichment mechanisms of coating materials have been illustrated preliminarily.
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