Antagonists targeting eEF2 kinase rescue multiple aspects of pathophysiology in Alzheimer’s disease model mice

It is imperative to develop novel therapeutic strategies for Alzheimer's disease (AD) and related dementia syndromes based on solid mechanistic studies. Maintenance of memory and synaptic plasticity relies on de novo protein synthesis, which is partially regulated by phosphorylation of eukaryotic elongation factor 2 (eEF2) via its kinase eEF2K. Abnormally increased eEF2 phosphorylation and impaired mRNA translation have been linked to AD. We recently reported that prenatal genetic suppression of eEF2K is able to prevent aging-related cognitive deficits in AD model mice, suggesting the therapeutic potential of targeting eEF2K/eEF2 signaling in AD. Here, we tested two structurally distinct small-molecule eEF2K inhibitors in two different lines of AD model mice after the onset of cognitive impairments. Our data revealed that treatment with eEF2K inhibitors improved AD-associated synaptic plasticity impairments and cognitive dysfunction, without altering brain amyloid β (Aβ) and tau pathology. Furthermore, eEF2K inhibition alleviated AD-associated defects in dendritic spine morphology, post-synaptic density formation, protein synthesis, and dendritic polyribosome assembly. Our results may offer critical therapeutic implications for AD, and the proof-of-principle study indicates translational implication of inhibiting eEF2K for AD and related dementia syndromes. Cover Image for this issue: https://doi.org/10.1111/jnc.15392.

Effect of the passive films on CaCO3 scale depositing on Q235 steel: Electrochemical and surface investigation

The deposition of the CaCO₃ scale in circulating cooling water is a common and serious concern in the industry, which hinders the heat transfer, reduces water flow and blocks membrane filters. This paper aims at studying the effect of the γ-Fe₂O₃, Fe₂(MoO₄)₃·γ-Fe₂O₃ and FePO₄·γ-Fe₂O₃ passive films on CaCO₃ scale deposition on Q235 steel by electrochemical methods, including linear sweep voltammetry (LSV), chronoamperometry and electrochemical impedance spectroscopy (EIS) tests. The scale and corrosion inhibition performance of the passive films was evaluated by the residual current density (i_r) and charge transfer resistance (R_ct) values. Electrochemical results suggested that the passive films could inhibit corrosion and reduce the CaCO₃ scale deposition on Q235 steel and the FePO₄·γ-Fe₂O₃ complex passive film showed the best anti-scaling effect. Scanning electron microscope (SEM) and X-ray diffractometer (XRD) tests showed that the passive films could lead to a decrease in the proportion of aragonite to calcite under cathodic water reduction conditions and the composition of the FePO₄·γ-Fe₂O₃ complex passive film could deform the CaCO₃ crystal.

P-OGC14 Global Level of Harm Upper Gastrointestinal (GLEOHUG) – a multinational gastric cancer cross- sectional appraisal

Background

Gastric cancer (GC) is the 5^th most common malignancy and remains one of the major causes of worldwide cancer-related deaths. COVID-19 pandemic has had a significant impact on the provision of cancer care. This study aims to overview the global standpoint of gastric cancer patients (GCP) during the first year of the pandemic.

Methods

The Upper Gastrointestinal Surgeons (TUGS), within its Global Level of Harm Project, designed an online cross-sectional survey to assess how gastric cancer patient’s management changed during the first year of the pandemic. The questionnaire included 33 questions about expertise, kind of health system, hospital organization and screening policies, personal protective equipment (PPE), change in patient’s characteristics, preoperative, operative and postoperative management of GCP.

Results

There were 209 participants from 178 centres & 50 countries). Results showed: most hospitals (88,18%) had restricted areas for COVID-19 patients; 53.58% of surgeons were redeployed; most frequent COVID-19 screening method was PCR (78,82%) & chest CT-scan (25,62%), and 55.98% lack full PPE. Preoperative management: 43.16% noted reduction in multidisciplinary teams (MDT) meetings; 28,42% increase in cT2 or higher GCP; 34,74% increase in metastatic (M1) GCP; 26,84% increase in patients receiving definitive palliative treatment; 23,68% note increase in frail patients; 50% increase in waiting list time; and 41,58% faced problems in the provision of oncological treatment. Operative management: 54,50% decrease in elective gastrectomies; 29,10% increase in urgent/semi-urgent gastrectomies; 37,04% decrease in the number of minimally-invasive gastrectomies (MIG); & 18,52% increase in the number of palliative surgeries. Postoperative management: 16,48% increase in the overall complication rate (OCR); 12,64% increase in the number of Clavien-Dindo 3 or higher complications; 8,13% increase in the leak rate; increase in pulmonary infections (26,79%) and bowel obstruction (2,39%); 44,51% note postoperative COVID-19; 15,38% increase in 30-days mortality; 23,08% mortality due to COVID-19 infection; 17,58% increase in the need for adjuvant treatment. Most patients were postoperatively assessed either through a face-to-face consultation or a hybrid approach.

Conclusions

COVID-19 pandemic has affected gastric cancer management by decreased frequency of MDT’s, higher clinical-stage migration and fuelled frailty. The pandemic increased waiting list time, the number of urgent and palliative surgeries, OCR, Clavie-Dindo 3 or higher complications, leak rate, and pulmonary infections. There was a noticeable high rate of postoperative COVID-19 infection and associated mortality. Further multicentric studies are warranted to affirm these findings.

ac4C acetylation of RUNX2 catalyzed by NAT10 spurs osteogenesis of BMSCs and prevents ovariectomy-induced bone loss

N-acetyltransferase 10 (NAT10) is the key enzyme for N4-acetylcytidine (ac4C) modification of mRNA, which participates in various cellular processes and is related to many diseases. Here, we explore the relationships among osteoblast differentiation, NAT10, and ac4C, and we found that NAT0 expression and the ac4C level of total RNA were decreased in the bone tissues of bilateral ovariectomized (OVX) mice and osteoporosis patients. Adenoviruses overexpressing NAT10 reversed bone loss, and Remodelin, an NAT10 inhibitor, enhanced the loss of bone mass in OVX mice. Moreover, bone marrow-derived mesenchymal stem cells (BMSCs) with low-level ac4C modification formed fewer calcium nodules in vitro with NAT10 silencing, whereas BMSCs with high-level ac4C modification formed more calcium nodules with NAT10 overexpression. Moreover, we demonstrated that the ac4C level of runt-related transcription factor 2 (RUNX2) mRNA was increased after BMSCs were cultured in osteogenic medium (OM) and decreased after NAT10 silencing. The RUNX2 mRNA half-life and protein expression decreased after silencing NAT10 in BMSCs. Therefore, NAT10-based ac4C modification promotes the osteogenic differentiation of BMSCs by regulating the RUNX2 ac4C level. Because abnormal levels of NAT10 are probably one of the mechanisms responsible for osteoporosis, NAT10 is a new potential therapeutic target for this disease.

Role of miR-27a in the regulation of cellular function via the inhibition of MAP2K4 in patients with asthma

Asthma is a respiratory disease with a clinically high incidence, and repeated attacks of asthma severely affect the quality of life and even pose a threat to health, leading to severe burdens on families and even the society. A thorough understanding of the pathogenesis of asthma is essential for the prevention and treatment of asthma. This study aimed to examine the effect of the microRNA miR-27a on asthma and its relationship with mitogen activated protein kinase 4 (MAP2K4). Patients with asthma admitted to our hospital from August 2016 to August 2018 and healthy participants in the same period were included in this prospective analysis. The mRNA expression levels of miR-27a and MAP2K4 in peripheral blood were determined. Airway smooth muscle cells (ASMCs) were used to study the effects of miR-27a and MAP2K4 on cell biological behavior. The relationship between miR-27a and MAP2K4 was verified using dual-luciferase reporter assay. miR-27a expression was increased and MAP2K4 mRNA expression was decreased in asthma (P < 0.05). Increasing miR-27a expression and inhibiting MAP2K4 expression could enhance the activity of ASMCs, whereas inhibiting miR-27a expression and increasing MAP2K4 expression had the opposite effect (P < 0.05). Dual-luciferase reporter assay results showed that the fluorescence activity of MAP2K4-wild type was inhibited by increased miR-27a expression (P < 0.05). miR-27a promotes the proliferation and invasion of ASMCs by targeting MAP2K4 and is involved in the occurrence of asthma.

LINC00205, a YY1-modulated lncRNA, serves as a sponge for miR-26a-5p facilitating the proliferation of hepatocellular carcinoma cells by elevating CDK6

OBJECTIVE

LINC00205, a bidirectional lncRNA, located at human chromosome 21q22.3, was recently characterized as an oncogenic molecule contributing to cell proliferation in several cancers, including hepatocellular carcinoma (HCC). In the present study, we aim to probe the new molecular mechanism for LINC00205 controlling the proliferation of HCC cells.

PATIENTS AND METHODS

The expression status of LINC00205, miR-26a-5p, as well as CDK6 in HCC tissues/cell lines was determined by quantitative real-time PCR (qPCR). The cell proliferative activity was measured by using the Cell Counting Kit (CCK)-8 assay. Flow cytometry was performed to analyze cell cycle progression and apoptosis induction. The interaction among LINC00205, miR-26a-5p and CDK6, as well as transcription efficiency of LINC00205 promoter were examined by Dual-Luciferase reporter assay. Western blot was conducted to evaluate the protein levels of CDK6 in SNU-449 cells. The direct interplay between YY1 and LINC00205 promoter was detected by ChIP-qPCR.

RESULTS

LINC00205 was strongly expressed in HCC tissues and cell lines. Elevated LINC00205 expression was positively associated with worse prognosis as well as pathological grade in HCC. Suppression of LINC00205 could impede the proliferation of HCC cells by triggering the G0/G1-phase cell cycle arrest and apoptosis in vitro. Mechanistically, we illustrated that LINC00205 could accelerate the proliferation of HCC cells by boosting CDK6 expression via sponging miR-26a-5p. Moreover, we unveiled that LINC00205 could be activated by transcription factor Yin Yang-1 (YY1) as its direct downstream target.

CONCLUSIONS

LINC00205, a novel YY1-modulated lncRNA, can facilitate the proliferation of HCC cells through YY1/miR-26a-5p/CDK6 pathway, and may serve as a promising diagnostic biomarker and therapeutic target for HCC.

Assessment of peripheral neuropathy in type 2 diabetes by diffusion tensor imaging: A case-control study

OBJECTIVES

This study aimed to evaluate diabetes peripheral neuropathy (DPN) by diffusion tensor imaging (DTI) and explore the correlation between DTI parameters and electrophysiological parameters.

METHODS

We examined tibial nerve (TN) and common peroneal nerve (CPN) of 32 DPN patients and 23 healthy controls using T1-weighted magnetic resonance imaging and DTI. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) of TN and CPN were measured and compared between groups. Spearman correlation coefficient was used to explore the relationship between DTI parameters and electrophysiology parameters in the DPN group. Diagnostic value was assessed by receiver operating characteristic (ROC) analysis.

RESULTS

In the DPN group, FA was decreased (p < 0.0001) and MD and RD were increased (p < 0.05, p < 0.001) in the TN and CPN compared with the values of healthy control group. Moreover, in the DPN group, FA was positively correlated with motor nerve conduction velocity (MCV) (p < 0.0001), and both MD and RD were negatively correlated with MCV (p < 0.05, p < 0.001). However, there was no correlation between AD and any electrophysiological parameters. Among all DTI parameters, FA displayed the best diagnostic accuracy, with an area under the ROC curve of 0.882 in TN and 0.917 in CPN.

CONCLUSION

FA and RD demonstrate appreciable diagnostic accuracy. Furthermore, they both have a moderate correlation with MCV.

MYOD1 c.365G&gt;T, p.L122R Variant Detection by Droplet Digital PCR (ddPCR)

Introduction/Objective

Rhabomyosarcomas (RMS) are a group of skeletal muscle tumors that include embryonal, alveolar, pleomorphic, spindle cell/sclerosing subtypes (SC/SRMS). Spindle cell RMS occurs in both adult and pediatric populations, and is associated with either more aggressive or better clinical outcomes respectively. A recurrent hotspot variant in MYOD1, p.L122R (NM_002478.4 c.365G&gt;T), has been described in SC/SRMS. The classification of this diagnosis is evolving, with VGLL2 and NCOA2 fusions defining the diagnosis in young children, and MYOD1 p.L122R defining the diagnosis in older children. The MYOD1 p.L122R variant seems to be associated with more aggressive disease, and may be increasingly used in risk stratification with intensification of treatment.

Methods/Case Report

A digital droplet PCR (ddPCR) assay was used to detect the MYOD1 p.L122R in DNA samples with RMS. Patients and controls were coded as positive or negative, and tested for association with clinical features and outcome.

Results (if a Case Study enter NA)

Known-positive cohort of samples was limited by the extreme rarity of this tumor. “Known-positive” status was established by confirmation of the variant with an external clinically-validated assay. The six known positive samples were assessed by ddPCR for the presence of MYOD1 L122R. The L122R variant was detected in all six variants for a sensitivity of 100%. DNA and/or TNA obtained from known wild-type FFPE and frozen material was assessed, for a total of nine unique samples (1 synthetic, 8 patient-derived). All 9 samples were wild- type, with no positive droplets detected, for a specificity of 100%.

Conclusion

Our MYOD1 c.365G&gt;T, p.L122R variant detection by droplet digital PCR (ddPCR) assay is a robust, reproducible, specific and sensitive method to detect the MYOD1 hotspot mutation.

Carbapenem-resistant Enterobacterales colonization and subsequent infection in a neonatal intensive care unit in Shanghai, China

Background

Colonization has been reported to play an important role in carbapenem-resistant Enterobacterales (CRE) infection; however, the extent to which carriers develop clinical CRE infection and related risk factors in neonatal intensive care unit (NICU) patients is unclear.

Aim

To investigate the frequency of CRE colonization and its contribution to infections in NICU patients.

Methods

CRE colonization screening and CRE infection surveillance were performed in the NICU in 2017 and 2018.

Findings

Among 1230 unique NICU patients who were screened for CRE colonization, 144 patients tested positive (11.7%, 144/1230), with 9.2% (110/1197) in the intestinal tract, which was higher than that in the upper respiratory tract (6.6%, 62/945) (P=0.026). Gestational age, low birth weight and prolonged hospitalization were risk factors for CRE colonization (all P<0.001). Diversilab homology monitoring found an overall 17.4% (25/144) risk of infection among patients colonized with CRE. For carbapenem-resistant Klebsiella pneumoniae (CR-KP) and carbapenem-resistant Escherichia coli (CR-ECO), the risks were 19.1% (21/110) and 13.8% (4/29), respectively. The independent risk factors for CR-KP clinical infection among CR-KP carriers were receiving mechanical ventilation (odds ratio (OR), 10.177; 95% confidence interval (CI), 2.667–38.830; P=0.013), a high level of neonatal nutritional risk assessment (OR, 0.251; 95% CI, 0.072–0.881; P=0.031) and a high neonatal acute physiology II (SNAP-II) score (OR, 0.256; 95% CI, 0.882–1.034; P=0.025).

Conclusions

The colonization of CRE may increase the incidence of corresponding CRE infection in NICU patients. Receiving mechanical ventilation, malnutrition and critical conditions with high SNAP-II scores were independent risk factors for subsequent CR-KP clinical infection.

Efficient passivation of n-type and p-type silicon surface defects by hydrogen sulfide gas reaction

An efficient surface defect passivation is observed by reacting clean Si in a dilute hydrogen sulfide-argon gas mixture (<5% H₂S in Ar) for both n-type and p-type Si wafers with planar and textured surfaces. Surface recombination velocities of 1.5 and 8 cm s^-1are achieved on n-type and p-type Si wafers, respectively, at an optimum reaction temperature of 550 °C that are comparable to the best surface passivation quality used in high efficiency Si solar cells. Surface chemical analysis using x-ray photoelectron spectroscopy shows that sulfur is primarily bonded in a sulfide environment, and synchrotron-based soft x-ray emission spectroscopy of the adsorbed sulfur atoms suggests the formation of S-Si bonds. The sulfur surface passivation layer is unstable in air, attributed to surface oxide formation and a simultaneous decrease of sulfide bonds. However, the passivation can be stabilized by a low-temperature (300 °C) deposited amorphous silicon nitride (a-Si:N_X:H) capping layer.

Micromagnetic simulation of microstructure effect for binary-main-phase Nd-Ce-Fe-B magnets

We investigate the magnetic properties of a chemically heterogeneous binary-main-phase (BMP) Nd-Ce-Fe-B magnet with a core-shell structure via micromagnetic simulation. It is found that the coercivity strongly depends on the shell thickness. The BMP magnet's coercivity initially increases and then decreases with increasing Nd-rich shell thickness, and so there is the optimal shell thickness which shows the maximum coercivity for any given Ce concentration. The simulation shows the significant difference in coercivity and maximum energy product between the BMP and single-main-phase magnets. Notably, the magnetization reversal mechanism of the BMP magnet is revealed in the simulation. Local reversals in the BMP magnet first occur in the Ce-rich shells, followed by the Nd-rich cores. Then, the magnetization in Ce-rich core/Nd-rich shell typed grains is switched after reversed magnetization of all the Nd-rich core/Ce-rich shell typed grains. The BMP magnet represents a further increased coercivity for a larger GB thickness, which can be well explained by a maximum stray field.

A genome-wide association study reveals additive and dominance effects on growth and fatness traits in large white pigs

The dominance effect is a kind of non-additive effect due to the interaction between alleles at the same locus. Quantitative traits such as growth traits in farm animals have been found to be influenced by dominance effects. However, dominance effects are usually ignored in the genome-wide association study (GWAS) of complex traits for farm animals. In this study, we performed GWAS and genetic parameters estimation for the two traits age at 100 kg (AGE) and backfat thickness at 100 kg (BF) of 3572 Large White pigs. The pigs were from three breeding farms of China and were genotyped by an in-house designed 50k SNP chip. Our results showed significant non-zero variance for the dominance effect of AGE, while the dominance effect of BF was not significant. Using a GWAS model accounting for both additive and dominance effects, we identified three additive and two dominance significant SNPs for the trait AGE. For the trait BF, three genome-wide significant additive SNPs were detected, but no significant SNP was found for the dominance effect. In total, six important functional genes (NPAS3, USP16, PARN, ARL15, GPC3, ABHD4) near significant SNPs were identified as candidate genes associated with AGE or BF. Notably, ARL15 and PARN were associated with AGE near the dominance association signals. Overall, the newly detected SNPs and newly identified candidate genes in our study added new information about the genetic architectures of growth and fatness traits in pigs, and have the potential to be applied to the pig breeding program in the future.

Design and Performance Evaluation of a Single-Phase Driven Ultrasonic Motor Using Bending-Bending Vibrations

An ultrasonic motor as a kind of smart material drive actuator has potential in robots, aerocraft, medical operations, etc. The size of the ultrasonic motor and complex circuit limits the further application of ultrasonic motors. In this paper, a single-phase driven ultrasonic motor using Bending-Bending vibrations is proposed, which has advantages in structure miniaturization and circuit simplification. Hybrid bending vibration modes were used, which were excited by only single-phase voltage. The working principle based on an oblique line trajectory is illustrated. The working bending vibration modes and resonance frequencies of the bending vibration modes were calculated by the finite element method to verify the feasibility of the proposed ultrasonic motor. Additionally, the output performance was evaluated by experiment. This paper provides a single-phase driven ultrasonic motor using Bending-Bending vibrations, which has advantages in structure miniaturization and circuit simplification.

Development and usage of the digital SAMG system

In order to reduce the work burden during the training and drilling of the severe accident and severe accident management guidelines, and improve the implementation efficiency of the guidelines, a method of digitizing the SAMG program files is proposed. A set of digital SAMG system supported by information technology and combined with software and hardware is developed to transform the manual processes of paper file browsing, data searching, logical judgment and auxiliary calculation into automatic and digital processes, which can be used for SAMG training and drilling, and also for verifying the SAMG execution process and the effectiveness of mitigation measures.

Brain-specific suppression of AMPKα2 isoform impairs cognition and hippocampal LTP by PERK-mediated eIF2α phosphorylation

The AMP-activated protein kinase (AMPK) is a molecular sensor to maintain energy homeostasis. The two isoforms of the AMPK catalytic subunit (AMPKα1 and α2) are both expressed in brains, but their roles in cognition are unknown. We generated conditional knockout mice in which brain AMPKα isoforms are selectively suppressed (AMPKα1/α2 cKO), and determined the isoform-specific effects in mice of either sex on cognition and synaptic plasticity. AMPKα2 cKO but not AMPKα1 cKO displayed impaired cognition and hippocampal late long-term potentiation (L-LTP). Further, AMPKα2 cKO mice exhibited decreased dendritic spine density and abnormal spine morphology in hippocampus. Electron microscope imaging demonstrated reduced postsynaptic density formation and fewer dendritic polyribosomes in hippocampi of AMPKα2 cKO mice. Biochemical studies revealed unexpected findings that repression of AMPKα2 resulted in increased phosphorylation of mRNA translational factor eIF2α and its kinase PERK. Importantly, L-LTP failure and cognitive impairments displayed in AMPKα2 cKO mice were alleviated by suppressing PERK activity pharmacologically or genetically. In summary, we demonstrate here that brain-specific suppression of AMPKα2 isoform impairs cognition and hippocampal LTP by PERK-mediated eIF2α phosphorylation, providing molecular mechanisms linking metabolism, protein synthesis, and cognition.

Hsa-miR-4730 as a new and potential diagnostic and prognostic indicators for pancreatic cancer

OBJECTIVE

Pancreatic cancer is a gastrointestinal tumor with the highest malignancy and few diagnostic and prognostic markers. Patients with disease have a 5-year survival rate that is not more than 10%. As a research hotspot in recent years, miRs (microRNAs) are differentially expressed in various tumors, so they can be used as the potential diagnostic and prognostic markers. In this study, differentially expressed miRs in patients with pancreatic cancer were screened out through the GEO chip, to provide potential markers for clinical practice. This study aimed to explore the expression and potential value of miR-4730 in pancreatic cancer.

PATIENTS AND METHODS

Differentially expressed miRs in pancreatic cancer were analyzed through logging in GEO DataSets to download GSE112264. Fifty patients with pancreatic cancer who were treated in our hospital from May 2012 to January 2014 (Group A), 50 patients with benign pancreatic lesions during the same period (Group B), and 50 healthy individuals undergoing physical examinations (Group C) were enrolled in this study. The expression of miR-4730 in the serum and the cancer tissue was detected by qRT-PCR. The correlation of miR-4730 with pathological data, and the diagnostic values of differential indicators in the data were analyzed. The patients were followed up for 5 years to observe the relationship between miR-4730 and their survival.

RESULTS

The analysis of the GEO chip showed 305 differentially expressed miRs, among which 225 were highly expressed and 80 were lowly expressed, with miR-4730 differentially expressed most. The expression of serum miR-4730 in Group A was significantly lower than that in Groups B and C (p<0.05), so miR-4730 had a diagnostic value. The expression of miR-4730 in the cancer tissue was significantly lower than that in the adjacent tissue. The correlation analysis showed that the expression of miR-4730 in the cancer tissue was positively correlated with that in the serum. Patients with low miR-4730 expression had poorly differentiated pancreatic cancer, and patients with stages III+IV of pancreatic cancer had higher incidences of lymphatic invasion and distal metastasis (p<0.05), so miR-4730 had a diagnostic value. The 3- and 5-year survival rates in the high miR-4730 expression group were higher than those in the low expression group (both p<0.05). TNM staging, lymphatic invasion, distal metastasis, and miR-4730 were independent prognostic factors for the 3- and 5-year survival of patients with pancreatic cancer.

CONCLUSIONS

For patients with pancreatic cancer, those with low miR-4730 expression have poor survival and prognoses, so miR-4730 can be used as a potential observational index for the prognosis and diagnosis of the disease.