The DDR-related gene signature with cell cycle checkpoint function predicts prognosis, immune activity, and chemoradiotherapy response in lung adenocarcinoma

BACKGROUND

As a DNA surveillance mechanism, cell cycle checkpoint has recently been discovered to be closely associated with lung adenocarcinoma (LUAD) prognosis. It is also an essential link in the process of DNA damage repair (DDR) that confers resistance to radiotherapy. Whether genes that have both functions play a more crucial role in LUAD prognosis remains unclear.

METHODS

In this study, DDR-related genes with cell cycle checkpoint function (DCGs) were selected to investigate their effects on the prognosis of LUAD. The TCGA-LUAD cohort and two GEO external validation cohorts (GSE31210 and GSE42171) were performed to construct a prognosis model based on the least absolute shrinkage and selection operator (LASSO) regression. Patients were divided into high-risk and low-risk groups based on the model. Subsequently, the multivariate COX regression was used to construct a prognostic nomogram. The ssGSEA, CIBERSORT algorithm, TIMER tool, CMap database, and IC50 of chemotherapeutic agents were used to analyze immune activity and responsiveness to chemoradiotherapy.

RESULTS

4 DCGs were selected as prognostic signatures, and patients in the high-risk group had a lower overall survival (OS). The lower infiltration levels of immune cells and the higher expression levels of immune checkpoints appeared in the high-risk group. The damage repair pathways were upregulated, and chemotherapeutic agent sensitivity was poor in the high-risk group.

CONCLUSIONS

The 4-DCGs signature prognosis model we constructed could predict the survival rate, immune activity, and chemoradiotherapy responsiveness of LUAD patients.

[Atorvastatin inhibits malignant behaviors and induces apoptosis in human glioma cells by up-regulating miR-146a and inhibiting the PI3K/Akt signaling pathway]

OBJECTIVE

To explore the effect of atorvastatin (AVT) on biological behaviors and the miR-146a/PI3K/Akt signaling pathway in human glioma cells.

METHODS

Human glioma U251 cells were treated with 8.0 μmol/L AVT or transfected with a miR-146a inhibitor or a negative control fragment (miR-146a NC) prior to AVT treatment. RT-PCR was used to detect miR-146a expression in the cells, and the changes in cell proliferation rate, apoptosis, cell invasion and migration were detected using MTT assay, flow cytometry, and Transwell assay. Western blotting was performed to detect the changes in cellular expressions of proteins in the PI3K/Akt signaling pathway.

RESULTS

AVT treatment for 48 h resulted in significantly increased miR-146a expression and cell apoptosis (P < 0.01) and obviously lowered the cell proliferation rate, invasion index, migration index, and expressions of p-PI3K and p-Akt protein in U251 cells (P < 0.01). Compared with AVT treatment alone, transfection with miR-146a inhibitor prior to AVT treatment significantly reduced miR-146a expression and cell apoptosis (P < 0.01), increased the cell proliferation rate, promoted cell invasion and migration, and enhanced the expressions of p-PI3K and p-Akt proteins in the cells (P < 0.01); these effects were not observed following transfection with miR-146a NC group (P>0.05).

CONCLUSION

AVT can inhibit the proliferation, invasion and migration and promote apoptosis of human glioma cells possibly by up-regulating miR-146a expression and inhibiting the PI3K/Akt signaling pathway.

Electrically tunable spin-orbit interaction in an InAs nanosheet

We report an experimental study of the spin-orbit interaction (SOI) in an epitaxially grown free-standing InAs nanosheet in a dual-gate field-effect device. Gate-transfer characteristic measurements show that independent tuning of the carrier density in the nanosheet and the potential difference across the nanosheet can be efficiently achieved with the use of a dual gate. The quantum transport characteristics of the InAs nanosheet are investigated by magnetoconductance measurements at low temperatures. It is shown that the electron transport in the nanosheet can be tuned from the weak antilocalization to the weak localization and then back to the weak antilocalization regime with a voltage applied over the dual gate without a change in the carrier density. The spin-orbit length extracted from the magnetoconductance measurements at a constant carrier density exhibits a peak value at which the SOI of the Rashba type is suppressed and the spin relaxation due to the presence of an SOI of the Dresselhaus type in the nanosheet can be revealed. Energy band diagram simulations have also been carried out for the device under the experimental conditions and the physical insights into the experimental observations have been discussed in light of the results of simulations.

AB1335 BONE MARROW EDEMA SCORE IN HAND X-RAY FILM BY AI DEEP LEARNING ASSOCIATE WITH MRI BONE EDEMA IN RHEUMATOID ARTHRITIS

Background

Rapid radiographic progression (RRP) was reported to be one of clinical symptom in difficult to treat RA(D2T RA) (1). Eular recommendation for imaging showed BME is strong and independent prognostic factor for bone destruction(2). We reported bone marrow edema (BME) in MRI image was most associated with RRP compared with bone erosion, synovitis in Adalimumab add-on therapy in MTX-IR RA patients(3). To rescue RRP, early detection of BME is important although cost of MRI is expensive and hard to repeat.

Objectives

To investigate the score of BME in hand X ray film by deep learning between X ray film and MRI BME information can discriminate the differences between BME and non-BME images.

Methods

In this work, we use a neural network consisted of convolutional layers and fully connected layers to classify X-ray images (Figure 1) In this paper, the output is the socre of BME which ranges from 0 to1(threshold = 0.4). We also used an interpretation technique called the Grad-CAM for visual explanations. Hand MRI (1.5T) were used.

Figure 1.

The convolutional neural network design. A red block “Conv” means a convolutional block. It contains a 2D convolution layer, a leaky relu activation function, a maxpooling layer and a batch normalization layer. The numbers above each “Conv” block are (kernal size, kernal size, kernal number). A green block “FC” is a fully connection layer. The number above it is (neuron number). After the last Softmax layer, the output becomes the probability of BME which ranges from 0 to 1.

Results

Regarding data split, 104 images including 79 non-BME images and 25 BME images are used as a hold-out test set. The rest of the images (473 images) are used as training data and validation data. Five fold cross-validation is used for these 473images. For each fold, there are about 378 images including 297 non-BME images and 81 BME images in the training set. There are about 95 images including 74 non-BME images and 21 BME images in the validation set. In order to fully utilize every image and unify the distribution of the training set and the validation set, the ratio of non-BME and BME is controlled to be the same which is about 3.66:1. The five folds showed similar performance on the hold-out test set. AUC is the area under the ROC curve. As the result, AUC which indicates the general performance of this model, ranged from 0.88 to 0.91. The average precision was 63% and the average recall rate was 87%. In this experiment, the initialization seed will greatly influence the final result. For example, AUC can be reduced to 0.73 from 0.89 because of a different initialization seed. It perhaps results from the shortage of data, which can easily make the neural network drop into a local minimum.We also utilized Grad-cam to visualize the result. The result of Grad-cam shows the importance of each part to the final prediction(Figure 2).

Figure 2.

Result of Grad-cam. Numbers in the parenthesises are the possibilities of BME. The middle case is unexpected because red region is the surrounding of the hand. The left and right cases may indicate the evidence for prediction.

Conclusion

The preliminary result is much better than a random guess. According to this result, there should be a certain difference between BME and non-BME images. If it’s the characteristic of BME that domains this difference, our classification algorithm will be feasible for BME. Our future work is to justify the evidence of the predictions and improve performance.

References

[1]Nagy G et al. Eular definition of difficult- to - treat to rheumatoid arthritis. Ann Rheum Dis 2021;80:31-35

[2]Colebatch AN et al. Eular recommendation for the use of imaging of joints in the clinical management of rheumatoid arthritis. Ann Rheum Dis 2013;72: 804-814

[3]Katayama K et al. Bone marrow OEDEMA is more associated with rapid radiographic progression than in synovitis or bone erosion by using low field MRI in bio-naiive rheumatoid arthritis patients treated with adalimumab and methotrexate combination therapy. Ann Rheum Dis 2014, eular meeting SAT0100.

Disclosure of Interests

None declared

Fabrication and characterization of InSb nanosheet/hBN/graphite heterostructure devices

Semiconductor InSb nanosheet/hexagonal boron nitride (hBN)/graphite trilayers are fabricated, and single- and double-gate devices made from the trilayers are realized and characterized. The InSb nanosheets employed in the trilayer devices are epitaxially grown, free-standing, zincblende crystals and are in micrometer lateral sizes. The hBN and graphite flakes are obtained by exfoliation. Each trilayer is made by successively stacking an InSb nanosheet on an hBN flake and on a graphite flake using a home-made alignment stacking/transfer setup. The fabricated single- and double-gate devices are characterized by electrical and/or magnetotransport measurements. In all these devices, the graphite and hBN flakes are employed as the bottom gates and the gate dielectrics. The measurements of a fabricated single bottom-gate field-effect device show that the InSb nanosheet in the device has an electron field-effect mobility of ∼7300 cm²V^-1s^-1and a low gate hysteresis of ∼0.05 V at 1.9 K. The measurements of a double-gate Hall-bar device show that both the top and the bottom gate exhibit strong capacitive couplings to the InSb nanosheet channel and can thus tune the nanosheet channel conduction effectively. The electron Hall mobility in the InSb nanosheet of the Hall-bar device is extracted to be larger than 1.1 × 10⁴cm²V^-1s^-1at a sheet electron density of ∼6.1 × 10¹¹cm^-2and 1.9 K and, thus, the device exhibits well-defined Shubnikov-de Haas oscillations.

Anti-platelet Therapy Is Associated With Lower Risk of Dementia in Patients With Cerebral Small Vessel Disease

Introduction

Cerebral small vessel disease (CSVD) is common among older people and it could lead to dementia. Whether anti-platelet therapy (APT) could retard the cognitive decline of CSVD is unclear. The aim of the study was to evaluate, in newly diagnosed CSVD patients without dementia, the association between the APT and dementia during follow-up.

Methods

We conducted a nested case-control study within a CSVD cohort. Dementia cases, such as vascular dementia (VaD), Alzheimer’s disease (AD), and unspecified dementia (UD), were individually matched (1:1) to controls by age, sex, and follow-up time. Conditional logistic regression models were used to estimate the odds ratios (ORs) between APT and dementia.

Results

Of 9,991 patients in a cohort screened from January 2009 to December 2019 and followed-up until November 2020, 131 dementia cases were finally included and successfully matched to 131 controls. Among 262 patients with CSVD, the mean [standard deviation (SD)] age was 73.9 (7.9) years and 126 (48.1%) were men. The median [interquartile range (IQR)] follow-up periods were 4.73 (2.70–6.57) years in the control group and 2.94 (1.34–4.89) years in the case group. According to MRI at baseline, the case group showed higher CSVD burden in lacune(s) (p = 0.001), moderate-to-severe white matter hyperintensities (WMHs) (p = 0.015), enlarged perivascular spaces (EPVSs) in basal ganglia (p = 0.005), and brain atrophy (p &lt; 0.001). The APT was associated with the lower overall dementia risk and the matched OR was statistically significant (aOR 0.15, 95% CI 0.05–0.45, p = 0.001), and clopidogrel showed protective effects on overall dementia (aOR 0.30, 95% CI 0.14–0.62, p = 0.001).

Conclusion

Among newly diagnosed CSVD patients without dementia, APT was associated with a lower risk of dementia and clopidogrel might be an appropriate candidate in preventing dementia.

SET8 Inhibition Potentiates Radiotherapy by Suppressing DNA Damage Repair in Carcinomas

OBJECTIVE

SET8 is a member of the SET domain-containing family and the only known lysine methyltransferase (KMT) that monomethylates lysine 20 of histone H4 (H4K20me1). SET8 has been implicated in many essential cellular processes, including cell cycle regulation, DNA replication, DNA damage response, and carcinogenesis. There is no conclusive evidence, however, regarding the effect of SET8 on radiotherapy. In the current study we determined the efficacy of SET8 inhibition on radiotherapy of tumors and the underlying mechanism.

METHODS

First, we explored the radiotherapy benefit of the SET8 expression signature by analyzing clinical data. Then, we measured a series of biological endpoints, including the xenograft tumor growth in mice and apoptosis, frequency of micronuclei, and foci of 53BP1 and γ-H2AX in cells to detect the SET8 effects on radiosensitivity. RNA sequencing and subsequent experiments were exploited to verify the mechanism underlying the SET8 effects on radiotherapy.

RESULTS

Low expression of SET8 predicted a better benefit to radiotherapy in lung adenocarcinoma (LUAD) and invasive breast carcinoma (BRCA) patients. Furthermore, genetic deletion of SET8 significantly enhanced radiation treatment efficacy in a murine tumor model, and A549 and MCF7 cells; SET8 overexpression decreased the radiosensitivity. SET8 inhibition induced more apoptosis, the frequency of micronuclei, and blocked the kinetics process of DNA damage repair as 53BP1 and γ-H2AX foci remained in cells. Moreover, RNF8 was positively correlated with the SET8 impact on DNA damage repair.

CONCLUSION

Our results demonstrated that SET8 inhibition enhanced radiosensitivity by suppressing DNA damage repair, thus suggesting that SET8 potentiated radiotherapy of carcinomas. As new inhibitors of SET8 are synthesized and tested in preclinical and clinical settings, combining SET8 inhibitors with radiation warrants consideration for precise radiotherapy.

Research on Small Sample Dynamic Human Ear Recognition Based on Deep Learning

Due to the problem of insufficient dynamic human ear data, the Changchun University dynamic human ear (CCU-DE) database, which is a small sample human ear database, was developed in this study. The database fully considers the various complex situations and posture changes of human ear images, such as translation angle, rotation angle, illumination change, occlusion and interference, etc., making the research of dynamic human ear recognition closer to complex real-life situations, and increasing the applicability of human ear dynamic recognition. In order to test the practicability and effectiveness of the developed CCU-DE small sample database, we designed a dynamic human ear recognition system block diagram based on a deep learning model, which was pre-trained by a migration learning method. Aiming at multi-posture changes under different contrasts, translation and rotation motions, and with or without occlusion, simulation studies were conducted using the CCU-DE small sample database and different deep learning models, such as YOLOv3, YOLOv4, YOLOv5, Faster R-CNN, and SSD. The experimental results showed that the CCU-DE database can be well used for dynamic ear recognition, and it can be tested by using different deep learning models with higher test accuracy.

Suppressing Andreev Bound State Zero Bias Peaks Using a Strongly Dissipative Lead

Hybrid semiconductor-superconductor nanowires are predicted to host Majorana zero modes that induce zero-bias peaks (ZBPs) in tunneling conductance. ZBPs alone, however, are not sufficient evidence due to the ubiquitous presence of Andreev bound states. Here, we implement a strongly resistive normal lead in InAs-Al nanowire devices and show that most of the expected Andreev bound state-induced ZBPs can be suppressed, a phenomenon known as environmental Coulomb blockade. Our result is the first experimental demonstration of this dissipative interaction effect on Andreev bound states and can serve as a possible filter to narrow down the ZBP phase diagram in future Majorana searches.

A novel nomogram to predict overall survival in head and neck cancer survivors with radiation-induced brain necrosis

BACKGROUND AND PURPOSE

The study aimed to develop and validate a novel nomogram to predict overall survival in head and neck cancer survivors following the diagnosis of radiation-induced brain necrosis (RN).

MATERIALS AND METHODS

We included head and neck cancer survivors with RN from a radiation complications registry study. A total of 495 eligible patients were 7:3 randomly allocated to a training cohort and an internal validation cohort. The Least Absolute Shrinkage and Selection Operator (LASSO) regression was applied to select significant predictors of post-RN survival in the training cohort, and a multivariable Cox model was used to develop the nomogram. The performance of the nomogram was assessed using the internal validation cohort and externally validated using additional 88 RN patients.

RESULTS

We identified five predictors of post-RN survival using the training data: age, tumor progression before RN, lower cranial nerves injury, bilateral necrosis, and history of stroke. The nomogram showed favorable performance in the internal validation cohort (C-index 0.761, 95% CI 0.676 to 0.847) and in the external validation cohort (C-index 0.795, 95% CI 0.717 to 0.874). The decision curve analysis indicated that the nomogram was clinically useful when the probabilities of death ranging from 1% to 48% at 1 year, from 3% to 50% at 3 years, and exceeding 2% at 5 years after being diagnosed with RN.

CONCLUSION

In this LASSO-Cox model-based nomogram study, we developed and validated an easily applied model to predict overall survival in head and neck cancer survivors following an RN diagnosis.

Large-Composition-Range Pure-Phase Homogeneous InAs1-xSbx Nanowires

Narrow bandgap InAs_1-xSb_x nanowires show broad prospects for applications in wide spectrum infrared detectors, high-performance transistors, and quantum computation. Realizing such applications requires a fine control of the composition and crystal structure of nanowires. However, the fabrication of large-composition-range pure-phase homogeneous InAs_1-xSb_x nanowires remains a huge challenge. Here, we first report the growth of large-composition-range stemless InAs_1-xSb_x nanowires (0 ≤ x ≤ 0.63) on Si (111) substrates by molecular beam epitaxy. We find that pure-phase InAs_1-xSb_x nanowires can be successfully obtained by controlling the antimony content x, nanowire diameter, and nanowire growth direction. Detailed energy dispersive spectrum data show that the antimony is uniformly distributed along the axial and radial directions of InAs_1-xSb_x nanowires and no spontaneous core-shell nanostructures form in the nanowires. On the basis of field-effect measurements, we confirm that InAs_1-xSb_x nanowires exhibit good conductivity and their mobilities can reach 4200 cm² V^-1 s^-1 at 7 K. Our work lays the foundation for the development of InAs_1-xSb_x nanowire optoelectronic, electronic, and quantum devices.

Hypochloraemia following admission to hospital with heart failure is common and associated with an increased risk of readmission or death: a report from OPERA-HF

AIMS

Hypochloraemia is common in patients hospitalized with heart failure (HF) and associated with a high risk of adverse outcomes during admission and following discharge. We assessed the significance of changes in serum chloride concentrations in relation to serum sodium and bicarbonate concentrations during admission in a cohort of 1002 consecutive patients admitted with HF and enrolled into an observational study based at a single tertiary centre in the UK.

METHODS AND RESULTS

Hypochloraemia (<96 mmol/L), hyponatraemia (<135 mmol/L), and metabolic alkalosis (bicarbonate >32 mmol/L) were defined by local laboratory reference ranges. Outcomes assessed were all-cause mortality, all-cause mortality or all-cause readmission, and all-cause mortality or HF readmission. Cox regression and Kaplan-Meier curves were used to investigate associations with outcome. During a median follow-up of 856 days (interquartile range 272-1416), discharge hypochloraemia, regardless of serum sodium, or bicarbonate levels was associated with greater all-cause mortality [hazard ratio (HR) 1.44, 95% confidence interval (CI) 1.15-1.79; P = 0.001], all-cause mortality or all-cause readmission (HR 1.26, 95% CI 1.04-1.53; P = 0.02), and all-cause mortality or HF readmission (HR 1.41, 95% CI 1.14-1.74; P = 0.002) after multivariable adjustment. Patients with concurrent hypochloraemia and natraemia had lower haemoglobin and haematocrit, suggesting congestion; those with hypochloraemia and normal sodium levels had more metabolic alkalosis, suggesting decongestion.

CONCLUSION

Hypochloraemia is common at discharge after a hospitalization for HF and is associated with worse outcome subsequently. It is an easily measured clinical variables that is associated with morbidity or mortality of any cause.

China Registry Study on Cognitive Impairment in the Elderly: Protocol of a Prospective Cohort Study

Introduction: To develop appropriate strategies for early diagnosis and intervention of cognitive impairment, the identification of minimally invasive and cost-effective biomarkers for the early diagnosis of cognitive impairment is crucial and desirable. Therefore, the CHina registry study on cOgnitive imPairment in the Elderly (HOPE) study is designed to investigate the natural course of cognitive decline and explore the clinical, imaging, and biochemical markers for the detection and diagnosis of cognitive impairment on its earliest stage.

Methods: Approximately 5,000 Chinese elderly aged more than 50 years were recruited from Sun Yat-sen Memorial Hospital, Sun Yat-sen University in Guangzhou, China by the year 2024. All subjects were invited to complete the clinical assessment, neuropsychological assessment, the biological samples collection (blood and cerebrospinal fluid (CSF)], magnetic resonance imaging (MRI) examination, and optional amyloid and tau PET. The follow-up survey was conducted every 1 year to repeat these assessments for 20 years. To better clarify the relationship between potential risk factors and endpoint events [changes in cognitive score or incidence of mild cognitive impairment (MCI) and/or dementia], appropriate statistical methods were used to analyze the data, including but not limited to, such as linear mixed-effect model, competing risk model, or the least absolute shrinkage and selection operator model.

Significance: The CHina registry study on cOgnitive imPairment in the Elderly study is designed to explore the longitudinal changes in characteristics of participants with cognitive decline and to identify potential plasma and imaging biomarkers with cost-benefit and scalability advantages. The results will enable broader clinical access and efficient population screening and then improve the development of treatment and the quality of life for cognitive impairment at the early stage.

Trial registration number: NCT04360200.

Small-molecule inhibitors of P-Rex guanine-nucleotide exchange factors

P-Rex1 and P-Rex2 are guanine-nucleotide exchange factors (GEFs) that activate Rac small GTPases in response to the stimulation of G protein-coupled receptors and phosphoinositide 3-kinase. P-Rex Rac-GEFs regulate the morphology, adhesion and migration of various cell types, as well as reactive oxygen species production and cell cycle progression. P-Rex Rac-GEFs also have pathogenic roles in the initiation, progression or metastasis of several types of cancer. With one exception, all P-Rex functions are known or assumed to be mediated through their catalytic Rac-GEF activity. Thus, inhibitors of P-Rex Rac-GEF activity would be valuable research tools. We have generated a panel of small-molecule P-Rex inhibitors that target the interface between the catalytic DH domain of P-Rex Rac-GEFs and Rac. Our best-characterized compound, P-Rex inhibitor 1 (PREX-in1), blocks the Rac-GEF activity of full-length P-Rex1 and P-Rex2, and of their isolated catalytic domains, in vitro at low-micromolar concentration, without affecting the activities of several other Rho-GEFs. PREX-in1 blocks the P-Rex1 dependent spreading of PDGF-stimulated endothelial cells and the production of reactive oxygen species in fMLP-stimulated mouse neutrophils. Structure-function analysis revealed critical structural elements of PREX-in1, allowing us to develop derivatives with increased efficacy, the best with an IC₅₀ of 2 µM. In summary, we have developed PREX-in1 and derivative small-molecule compounds that will be useful laboratory research tools for the study of P-Rex function. These compounds may also be a good starting point for the future development of more sophisticated drug-like inhibitors aimed at targeting P-Rex Rac-GEFs in cancer.

Ursolic acid treats renal tubular epithelial cell damage induced by calcium oxalate monohydrate via inhibiting oxidative stress and inflammation

Ursolic acid (UA) has been proved to have antioxidant and anti-inflammatory effects. However, it is not clear whether it has a protective impact on kidney damage induced by crystals of calcium oxalate monohydrate (COM). This work aimed to make clear the potential mechanism of UA protecting COM-induced kidney damage. The results manifested that high- and low-dose UA reduced COM crystals in COM rats' kidney, down-regulated urea, creatinine, and neutrophil gelatinase-associated lipocalin (NGAL) levels in rat plasma, declined kidney tissue and HK-2 cell apoptosis, inhibited Bax expression but elevated Bcl-2 expression. Additionally, UA alleviated renal fibrosis in COM rats, repressed α-SMA and collagen I protein expressions in the kidney and COM rats' HK-2 cells, depressed COM-induced oxidative damage in vivo and in vitro via up-regulating Nrf2/HO-1 pathway, up-regulated SOD levels and reduced MDA levels, down-regulated TNF-α, IL-1β, and IL-6 levels in vivo and in vitro via suppressing activation of TLR4/NF-κB pathway. In summary, the results of this study suggest that COM-induced renal injury can be effectively improved via UA, providing powerful data support for the development of effective clinical drugs for renal injury in the future.

Blood-Brain Barrier Repair of Bevacizumab and Corticosteroid as Prediction of Clinical Improvement and Relapse Risk in Radiation-Induced Brain Necrosis: A Retrospective Observational Study

Background

Blood-brain barrier (BBB) disruption after endothelial damage is a crucial part of radiation-induced brain necrosis (RN), but little is known of BBB disruption quantification and its role in the evaluation of therapeutic effect and prognosis for drug treatment. In this retrospective study, BBB repair by bevacizumab and corticosteroid and the correlation between BBB permeability and treatment response and relapse were evaluated by dynamic contrast-enhanced MRI (DCE-MRI).

Methods

Forty-one patients with RN after radiotherapy for nasopharyngeal carcinoma (NPC) (28 treated with bevacizumab and 13 with corticosteroid), 12 patients with no RN after NPC radiotherapy, and 12 patients with no radiotherapy history were included as RN, non-RN, and normal groups, respectively. DCE-MRI assessed BBB permeability in white matter of bilateral temporal lobe. DCE parameters were compared at baseline among the three groups. DCE parameters after treatment were compared and correlated with RN volume decrease, neurological improvement, and relapse.

Results

The extent of BBB leakage at baseline increased from the normal group and non-RN group and to RN necrosis lesions, especially K ^trans (Kruskal-Wallis test, P < 0.001). In the RN group, bevacizumab-induced K ^trans and v _e decrease in radiation necrosis lesions (both P < 0.001), while corticosteroid showed no obvious effect on BBB. The treatment response rate of bevacizumab was significantly higher than that of corticosteroid [30/34 (88.2%) vs. 10/22 (45.4%), P < 0.001]. Spearman analysis showed baseline K ^trans, K _ep, and v _p positively correlated with RN volume decrease and improvement of cognition and quality of life in bevacizumab treatment. After a 6-month follow-up for treatment response cases, the relapse rate of bevacizumab and corticosteroid was 10/30 (33.3%) and 2/9 (22.2%), respectively, with no statistical difference. Post-bevacizumab K ^trans level predicted relapse in 6 months with AUC 0.745 (P < 0.05, 95% CI 0.546-0.943, sensitivity = 0.800, specificity = 0.631).

Conclusions

Bevacizumab improved BBB leakage in RN necrosis. DCE parameters may be useful to predict therapeutic effect and relapse after bevacizumab.

Bevacizumab Combined with Corticosteroids Does Not Improve the Clinical Outcome of Nasopharyngeal Carcinoma Patients With Radiation-Induced Brain Necrosis

Objective

Our aim was to compare the clinical outcomes of patients treated with bevacizumab combined with corticosteroids and those with bevacizumab monotherapy from a radiation-induced brain necrosis (RN) registry cohort (NCT03908502).

Methods

We utilized clinical data from a prospective RN registry cohort (NCT03908502) from July 2017 to June 2020. Patients were considered eligible if they had symptomatic RN after radiotherapy for nasopharyngeal carcinoma (NPC) and received bevacizumab (5 mg/kg, two to four cycles) with a minimum follow-up time of 3 months. The primary outcome was a 2-month response rate determined by MRI and clinical symptoms. Secondary outcomes included quality of life [evaluated by the abbreviated World Health Organization Quality of Life (WHOQOL-BREF) questionnaire] and cognitive function (evaluated by the Montreal Cognitive Assessment scale) at 2 months, RN recurrence during follow-up, and adverse events.

Results

A total of 123 patients (34 in the combined therapy group and 89 in the monotherapy group) were enrolled in our study with a median follow-up time of 0.97 year [interquartile range (IQR) = 0.35-2.60 years]. The clinical efficacy of RN did not differ significantly between patients in these two groups [odds ratio (OR) = 1.642, 95%CI = 0.584-4.614, p = 0.347]. Furthermore, bevacizumab combined with corticosteroids did not reduce recurrence compared with bevacizumab monotherapy [hazard ratio (HR) = 1.329, 95%CI = 0.849-2.079, p = 0.213]. The most common adverse events of bevacizumab were hypertension (17.89%), followed by nosebleed (8.13%) and fatigue (8.13%). There was no difference in grade 2 or more severe adverse events between the two groups (p = 0.811).

Interpretation

Our results showed that the treatment strategy of combining bevacizumab with corticosteroids did not lead to better clinical outcomes for RN patients with a background of radiotherapy for nasopharyngeal carcinoma.

miR-29b-3p Increases Radiosensitivity in Stemness Cancer Cells via Modulating Oncogenes Axis

Radioresistance conferred by cancer stem cells (CSCs) is the principal cause of the failure of cancer radiotherapy. Eradication of CSCs is a prime therapeutic target and a requirement for effective radiotherapy. Three dimensional (3D) cell-cultured model could mimic the morphology of cells in vivo and induce CSC properties. Emerging evidence suggests that microRNAs (miRNAs) play crucial roles in the regulation of radiosensitivity in cancers. In this study, we aim to investigate the effects of miRNAs on the radiosensitivity of 3D cultured stem-like cells. Using miRNA microarray analysis in 2D and 3D cell culture models, we found that the expression of miR-29b-3p was downregulated in 3D cultured A549 and MCF7 cells compared with monolayer (2D) cells. Clinic data analysis from The Cancer Genome Atlas database exhibited that miR-29b-3p high expression showed significant advantages in lung adenocarcinoma and breast invasive carcinoma patients’ prognosis. The subsequent experiments proved that miR-29b-3p overexpression decreased the radioresistance of cells in 3D culture and tumors in vivo through interfering kinetics process of DNA damage repair and inhibiting oncogenes RBL1, PIK3R1, AKT2, and Bcl-2. In addition, miR-29b-3p knockdown enhanced cancer cells invasion and migration capability. MiR-29b-3p overexpression decreased the stemness of 3D cultured cells. In conclusion, our results demonstrate that miR-29b-3p could be a sensitizer of radiation killing in CSC-like cells via inhibiting oncogenes expression. MiR-29b-3p could be a novel therapeutic candidate target for radiotherapy.

High-Performance Room-Temperature UV-IR Photodetector Based on the InAs Nanosheet and Its Wavelength- and Intensity-Dependent Negative Photoconductivity

Low-dimensional narrow-band-gap III-V semiconductors have great potential in high-performance electronics, photonics, and quantum devices. However, high-performance nanoscale infrared photodetectors based on isolated two-dimensional (2D) III-V compound semiconductors are still rare. In this work, we demonstrate a new type of photodetector based on the InAs nanosheet. The photodetector has high optoelectronic response in the ultraviolet-infrared band (325-2100 nm) at room temperature. The high-performance photodetector has very high responsivity (∼1231 A/W), EQE (2.2 × 10⁵ %), and detectivity (5.46 × 10¹⁰ Jones) to 700 nm light at low operating voltage (∼0.1 V). These results indicate that 2D InAs nanosheet devices have great potential in nano-optoelectronic devices and integrated optoelectronic devices. In addition, we observe for the first time that the InAs nanosheet devices have a negative photoconductivity (NPC) that is not only affected by the wavelength but also related to the optical power intensity of the light. After analyzing experimental data, we propose that the origin of the NPC may come from electron trapping, and two competing mechanisms of optical absorption and the photogating effect in the photoelectric response process cause the dependence on the light wavelength and optical power intensity.

Elucidation of SIRT-1/PGC-1α-associated mitochondrial dysfunction and autophagy in nonalcoholic fatty liver disease

Background

Nonalcoholic fatty liver disease (NAFLD) can lead to chronic liver diseases associated with mitochondrial damages. However, the exact mechanisms involved in the etiology of the disease are not clear.

Methods

To gain new insights, the changes affecting sirtuin 1 (SIRT-1) during liver fat accumulation was investigated in a NAFLD mouse model. In addition, the in vitro research investigated the regulation operated by SIRT-1 on mitochondrial structures, biogenesis, functions, and autophagy.

Results

In mice NAFLD, high-fat-diet (HFD) increased body weight gain, upregulated serum total cholesterol, triglycerides, aspartate aminotransferase, alanine aminotransferase, blood glucose, insulin levels, and liver malondialdehyde, and decreased liver superoxide dismutase activity. In liver, the levels of SIRT-1 and peroxisome proliferator-activated receptor-gamma coactivator -1α (PGC-1α) decreased. The expression of peroxisome proliferator-activated receptor-α and Beclin-1 proteins was also reduced, while p62/SQSTM1 expression increased. These results demonstrated SIRT-1 impairment in mouse NAFLD. In a well-established NAFLD cell model, exposure of the HepG2 hepatocyte cell line to oleic acid (OA) for 48 h caused viability reduction, apoptosis, lipid accumulation, and reactive oxygen species production. Disturbance of SIRT-1 expression affected mitochondria. Pre-treatment with Tenovin-6, a SIRT-1 inhibitor, aggravated the effect of OA on hepG2, while this effect was reversed by CAY10602, a SIRT-1 activator. Further investigation demonstrated that SIRT-1 activity was involved in mitochondrial biogenesis through PGC-1α and participated to the balance of autophagy regulatory proteins.

Conclusion

In conclusion, in high-fat conditions, SIRT-1 regulates multiple cellular properties by influencing on mitochondrial physiology and lipid autophagy via the PGC-1α pathway. The SIRT-1/PGC-1α pathway could be targeted to develop new NAFLD therapeutic strategies.

Effects of hsa_circ_0000711 expression level on proliferation and apoptosis of hepatoma cells

OBJECTIVE

To investigate the role of human serum albumin (hsa)_circular (circ)_0000711 in hepatocellular carcinoma (HCC). Circular ribonucleic acids (circRNAs) are proven in numerous studies to play crucial role in tumor biology, but their roles in HCC remain unknown to a great extent.

PATIENTS AND METHODS

The circRNA expression profile microarray was employed to screen differentially expressed circRNAs in tumor tissues and adjacent tissues from HCC patients, and Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR) assay was performed for further verification. Next, the target micro RNAs (miRNAs) and their messenger RNAs (mRNAs) of key circRNAs were predicted by bioinformatics software, and a circRNA-miRNA-mRNA regulatory network was constructed. Subsequently, KEGG and GO enrichment analyses were applied to predict the possible biological processes regulated by hsa_circ_0000711 and relevant signaling pathways. The miRNAs playing a key role in the circRNA-miRNA-mRNA regulatory network were then selected as the objects, and their direct binding to hsa_circ_0000711 was confirmed via luciferase reporter gene assay. Thereafter, hsa_circ_0000711 was overexpressed or knocked out, and the biological function of hsa_circ_0000711 was detected by cell counting kit-8 (CCK-8) assay, apoptosis detection, and 5-Ethynyl-2'-deoxyuridine (EdU) staining assay in vitro.

RESULTS

The results of expression profile screening revealed that there was a significant difference in the expression profile of circRNAs between tumor tissues and adjacent tissues in HCC patients. Based on the circRNA expression profile and RT-qPCR results, the expression level of hsa_circ_0000711 was overtly reduced in HCC tissues. In addition, miR-103a-3p had the highest eigenvector centrality in the circRNA-miRNA-mRNA regulatory network, suggesting that miR-103a-3p is a vital participant in the pathological mechanism of hsa_circ_0000711. The KEGG enrichment analysis results pointed out that the target genes regulated by hsa_circ_0000711 were clearly enriched in the tumor-associated signaling pathways. Besides, the results of GO enrichment analysis demonstrated that the biological processes regulated by hsa_circ_0000711 were mainly related to cell cycle regulation, so cell proliferation might be affected. The results of luciferase reporter gene and RT-qPCR assays showed that hsa_circ_0000711 directly bound to has-miR-103a-3p to serve as a molecular sponge. The results of CCK-8 and EdU staining assays revealed that the proliferation of hepatoma cells in hsa_circ_0000711 overexpression group was evidently enhanced. In addition, it was further found via flow cytometry that the apoptosis rate of cells was significantly raised in hsa_circ_0000711 low-expression group and dramatically declined in hsa_circ_0000711 overexpression group.

CONCLUSIONS

Overexpression of hsa_circ_0000711 promoted the proliferation and inhibited the apoptosis of hepatoma cells via targeting has-miR-103a-3p.

A highly tunable quadruple quantum dot in a narrow bandgap semiconductor InAs nanowire

Quantum dots (QDs) made from semiconductors are among the most promising platforms for the development of quantum computing and simulation chips, and they have the advantages of high density integration and compatibility with the standard semiconductor chip fabrication technology compared to other platforms. However, the development of a highly tunable semiconductor multiple QD system still remains a major challenge. Here, we demonstrate the realization of a highly tunable linear quadruple QD (QQD) in a narrow bandgap semiconductor InAs nanowire via a fine finger gate technique. The QQD is studied by electron transport measurements in the linear response regime. Characteristic two-dimensional charge stability diagrams containing four groups of resonant current lines of different slopes are obtained for the QQD. It is shown that these current lines arise from and can be individually assigned to resonant electron transport through the energy levels of different QDs. Benefitting from the excellent gate tunability, we also demonstrate the tuning of the QQD to regimes where the energy levels of two QDs, three QDs and all four QDs are energetically in resonance, respectively, with the Fermi level of the source and drain contacts. A capacitance network model is developed for the linear QQD and the simulated charge stability diagrams based on this model show good agreement with the experiments. Our work provides solid experimental evidence that narrow bandgap semiconductor nanowire multiple QDs could be used as a versatile platform to achieve integrated qubits for quantum computing and to perform quantum simulations of complex many-body systems.

Robust anomalous Hall effect and temperature-driven Lifshitz transition in Weyl semimetal Mn3Ge

Topological Weyl semimetals have attracted considerable interest because they manifest underlying physics and device potential in spintronics. Large anomalous Hall effect (AHE) in non-collinear antiferromagnets (AFMs) represents a striking Weyl phase, which is associated with Bloch-band topological features. In this work, we report robust AHE and Lifshitz transition in high-quality Weyl semimetal Mn3Ge thin film, comprising stacked Kagome lattice and chiral antiferromagnetism. We successfully achieved giant AHE in our Mn3Ge film, with a strong Berry curvature enhanced by the Weyl phase. The enormous coercive field HC in our AHE curve at 5 K reached an unprecedented 5.3 T among hexagonal Mn3X systems. Our results provide direct experimental evidence of an electronic topological transition in the chiral AFMs. The temperature was demonstrated to play an efficient role in tuning the carrier concentration, which could be quantitatively determined by the two-band model. The electronic band structure crosses the Fermi energy level and leads to the reversal of carrier type around 50 K. The results not only offer new functionality for effectively modulating the Fermi level location in topological Weyl semimetals but also present a promising route of manipulating the carrier concentration in antiferromagnetic spintronic devices.

ATM inhibition enhances cancer immunotherapy by promoting mtDNA leakage and cGAS/STING activation

Novel approaches are needed to boost the efficacy of immune checkpoint blockade (ICB) therapy. Ataxia telangiectasia mutated (ATM) protein plays a central role in sensing DNA double-stranded breaks (DSBs) and coordinating their repair. Recent data indicated that ATM might be a promising target to enhance ICB therapy. However, the molecular mechanism involved has not been clearly elucidated. Here, we show that ATM inhibition could potentiate ICB therapy by promoting cytoplasmic leakage of mitochondrial DNA (mtDNA) and activation of the cGAS/STING pathway. We show that genetic depletion of ATM in murine cancer cells delayed tumor growth in syngeneic mouse hosts in a T cell-dependent manner. Furthermore, chemical inhibition of ATM potentiated anti-PD-1 therapy of mouse tumors. ATM inhibition potently activated the cGAS/STING pathway and enhanced lymphocyte infiltration into the tumor microenvironment by downregulating mitochondrial transcription factor A (TFAM), which led to mtDNA leakage into the cytoplasm. Moreover, our analysis of data from a large patient cohort indicated that ATM mutations, especially nonsense mutations, predicted for clinical benefits of ICB therapy. Our study therefore provides strong evidence that ATM may serve as both a therapeutic target and a biomarker to enable ICB therapy.

A charge sensor integration to tunable double quantum dots on two neighboring InAs nanowires

A single quantum dot serving as a charge sensor is integrated to scalable double quantum dots using local top finger-gate techniques on two neighboring pure-phase InAs nanowires. The single dot built on one nanowire capacitively couples one of the double dots constructed on another nanowire via a metal bridge gate. The charge occupation states of double quantum dots can be accurately monitored by the sensor even in a few-electron regime in which transport tunneling current through the double dots vanishes. In the tunneling spectroscopy of double dots, electron inter dot tunneling process is absent; however, it can be illustrated by the sensor in terms of a transconductance line between the two closest triple points. Thus, tunnel coupling strength between the double dots is quantitatively extracted from the detectable charge transition. The highly tunable multiple quantum dots with integrated charge sensors on InAs nanowires could be an essential building block for quantum information processing technology.

Long noncoding RNA SNHG14 regulates ox-LDL-induced atherosclerosis cell proliferation and apoptosis by targeting miR-186-5p/WIPF2 axis

To investigate the role of small nucleolus RNA host gene 14 (SNHG14) in the progression of atherosclerosis (AS), bioinformatics analysis, and other relevant experiments (cell counting kit-8, flow cytometry, quantitative real-time polymerase chain reaction, luciferase reporter, RNA immunoprecipitation, RNA pull-down, and western blot assays) were done. The current study revealed that SNHG14 level was high in the serum of AS patients and oxidized low-density lipoprotein (ox-LDL)-induced AS cell lines. Besides, we found that SNHG14 accelerated cell proliferation while inhibited cell apoptosis in ox-LDL-induced AS cell lines. Next, SNHG14 was confirmed to be a sponge for miR-186-5p in AS cells, and it was validated that SNHG14 regulated AS cell proliferation and apoptosis by sponging miR-186-5p. Moreover, we uncovered that WAS-interacting protein family member 2 (WIPF2) was a downstream target of miR-186-5p in AS cells. Finally, it was demonstrated that miR-186-5p modulated AS cell proliferation and apoptosis via targeting WIPF2. To conclude, our research disclosed that SNHG14 affected ox-LDL-induced AS cell proliferation and apoptosis through miR-186-5p/WIPF2 axis, which may provide a theoretical basis for the treatment and diagnosis of AS.

Myricetin reduces cytotoxicity by suppressing hepcidin expression in MES23.5 cells

Multiple studies implicate iron accumulation in the substantia nigra in the degeneration of dopaminergic neurons in Parkinson’s disease. Indeed, slowing of iron accumulation in cells has been identified as the key point for delaying and treating Parkinson’s disease. Myricetin reportedly plays an important role in anti-oxidation, anti-apoptosis, anti-inflammation, and iron chelation. However, the mechanism underlying its neuroprotection remains unclear. In the present study, MES23.5 cells were treated with 1 × 10^–6 M myricetin for 1 hour, followed by co-treatment with 400 nM rotenone for 24 hours to establish an in vitro cell model of Parkinson’s disease. Our results revealed that myricetin alleviated rotenone-induced decreases in cell viability, suppressed the production of intracellular reactive oxygen species, and restored mitochondrial transmembrane potential. In addition, myricetin significantly suppressed rotenone-induced hepcidin gene transcription and partly relieved rotenone-induced inhibition of ferroportin 1 mRNA and protein levels. Furthermore, myricetin inhibited rotenone-induced phosphorylation of STAT3 and SMAD1 in MES23.5 cells. These findings suggest that myricetin protected rotenone-treated MES23.5 cells by potently inhibiting hepcidin expression to prevent iron accumulation, and this effect was mediated by alteration of STAT3 and SMAD1 signaling pathways.

Silver-assisted growth of high-quality InAs1- x Sb x nanowires by molecular-beam epitaxy

InAs_1-x Sb _x nanowires show promise for use in nanoelectronics, infrared optoelectronics and topological quantum computation. Such applications require a high degree of growth control over the growth direction, crystal quality and morphology of the nanowires. Here, we report on the silver-assisted growth of InAs_1-x Sb _x nanowires by molecular-beam epitaxy for the first time. We find that the growth parameters including growth temperature, indium flux and substrate play an important role in nanowire growth. Relatively high growth temperatures and low indium fluxes can suppress the growth of non-[111]-oriented nanowires on Si (111) substrates. Vertically aligned InAs_1-x Sb _x nanowires with high aspect ratios can be achieved on GaAs (111)B substrates. Detailed structural studies suggest that high-quality InAs_1-x Sb _x nanowires can be obtained by increasing antimony content. Silver-indium alloy segregation is found in ternary alloy InAs_1-x Sb _x nanowires, and it plays a key role in morphological evolution of the nanowires. Our work provides useful insights into the controllable growth of high-quality III-V semiconductor nanowires.

LncRNA MCM3AP-AS1 Promotes Cell Proliferation and Invasion Through Regulating miR-543-3p/SLC39A10/PTEN Axis in Prostate Cancer

Objective

Long-chain noncoding RNAs (lncRNAs) are key players in a wide range of biological processes, especially the pathogenesis and development of tumors. LncRNA MCM3AP-AS1 has been demonstrated to be involved in the invasion of various tumors including prostate cancer (PCa). However, its functions in PCa have not been fully elucidated.

Methods

qRT-PCR was conducted to measure the expression levels of lncRNA MCM3AP-AS1 and miR-543-3p in PCa tissue samples and cell lines. The expression levels of E-cadherin and SLC39A10 proteins were detected by Western blots. CCK-8 test, cell scratch test and trans-well test were used to evaluate the proliferation, invasion and migration abilities of PCa cells, respectively. Annexin V-FITC/PI experiments were carried out to determine the status of apoptosis. Bioinformatics analysis and Luciferase assay were used to explore the relationship between lncRNA MCM3AP-AS1, miR-543-3p and SLC39A10.

Results

In PCa tissue samples and cell lines, lncRNA MCM3AP-AS1 was up-regulated while miR-543-3p was down-regulated. Over-expression of MCM3AP-AS1 could promote the proliferation and invasion of PCa cells. Correlation analysis showed that the expression of MCM3AP-AS1 and miR-543-3p was significantly and inversely correlated. We further verified that miR-543-3p inhibitor was able to reverse si-MCM3AP-AS1-mediated inhibitory effects on the PCa cell proliferation, migration and invasion through regulating the downstream protein axis SLC39A10/PTEN/Akt. Finally, in vivo experiments indicated that knocking down of MCM3AP-AS1 could largely reduce tumor volumes, and decreased the ratio of Ki67-positive cells and the expression of SLC39A10 in tumor samples.

Conclusion

LncRNA MCM3AP-AS1 can promote the proliferation, migration and invasion abilities of PCa cells through regulating the miR-543-3p/SLC39A10/PTEN axis, which suggests that lncRNA MCM3AP-AS1 might be a potential target for prostate cancer therapy.

Effect of prolactin on penile erection: a cross-sectional study

Although elevated prolactin levels have been shown to inhibit penile erection, the relationship between prolactin and erection of the penile tip or base has not been extensively researched. We therefore investigated the prolactin's effects on erection of the penile tip and base, with a cross-sectional study of 135 patients with erectile dysfunction, based on scores of ≤21 on the International Index of Erectile Function-5. All patients were tested for nocturnal penile tumescence, blood pressure, serum glucose, total cholesterol, triglyceride, high-density lipoprotein, low-density lipoprotein, luteinizing hormone, follicle-stimulating hormone, prolactin, estradiol, testosterone, and progesterone. Univariate and multivariate analyses were used to assess the associations between prolactin levels and erection at the penile tip and base. We found no obvious relationship between erection time at penile tip and prolactin levels, but observed a negative correlation between base erection time and prolactin level (hazard ratio: −2.68; 95% confidence interval [CI]: −5.13–−0.22). With increasing prolactin concentration, multivariate analysis showed obvious reduction in base erection time among patients with normal Rigiscan results (hazard ratio: −3.10; 95% CI: −7.96–1.77; P < 0.05). Our data indicate that prolactin inhibits penile erection, particularly at the penile base. In addition, when the effective erection time of the penile base lasts longer than 10 min, prolactin has a more obvious inhibitory effect on penile base erection.

Enhancing the light emission of GaAs nanowires by pressure-modulated charge transfer

Strong non-radiative surface recombination in GaAs nanowires heavily blocks their applications as nanoscale optoelectronic devices. Pressure can effectively affect the surface recombination behaviors through tuning interactions between the surface of nanomaterials and the medium environment. Here, we report the pressure-induced light emission enhancement in GaAs nanowires via in situ high pressure photoluminescence measurements with nitrogen as the pressure transmitting medium. In the pressure range from 0 to 2.2 GPa, the photoluminescence intensity dramatically increases with increasing pressure. Above 2.2 GPa, the band gap transition from direct to indirect results in a sudden decrease in the photoluminescence intensity. Photoluminescence enhancement in GaAs nanowires also shows the pressure-dependent reversibility. The pressure-enhanced charge transfer effect between nitrogen molecules and the GaAs nanowire surface has been revealed according to first-principles calculations, which results in the reduction of surface states and the light-emission enhancement in GaAs NWs. Our study can provide a potential route for optimizing nanoscale functional devices.

Relationship between penile erection and the ratio of estradiol to testosterone: A retrospective study

Previous studies have found that the ratio of estradiol to testosterone (E2/T ratio) has a negative effect on sexual function, but the relationship between the E2/T ratio and erection of the penis is not clarified. We conducted a retrospective study of 183 patients with erectile dysfunction and 52 healthy men to investigate the relationship between penis base erection and tip erection. All participants underwent nocturnal penile tumescence tests and medical history checks and had relevant biochemical and endocrine indicators measured. The ratio of estradiol to testosterone was calculated. The relationship between E2/T ratio and erectile time of penile tip and penile base was determined by univariate analysis, multivariate analysis and stratification analysis. After adjusting for mixed factors, the results showed that the E2/T ratio had a more significant negative effect on the base of the penis compared with the tip of the penis (Hazard ratio: -4.34 95% CI: -6.52, -2.16 p = .0001). Moreover, when the effective erection time was ≥10 min, the negative effect of E2/T on penile root erection was more obvious (HR ratio: -4.46 95% CI: -6.50, -2.43 p < .0001). In summary, our study demonstrated a negative relationship between E2/T ratio and penile erection, particularly at the root of the penis.

In situ TEM observation of the vapor-solid-solid growth of <001[combining macron]> InAs nanowires

In situ transmission electron microscopy characterization is a powerful method in investigating the growth mechanism of catalyst-induced semiconductor nanowires. By providing direct evidence on the crystal growth at the atomic level, a real-time in situ heating investigation was carried out on Au-catalyzed <001[combining macron]> InAs nanowires. It was found that the Au catalyst maintained itself in the solid form during the nanowire growth, and maintained a fixed epitaxial relationship with its underlying InAs nanowire, indicating the vapor-solid-solid mechanism. Importantly, the growth of <001[combining macron]> InAs nanowires through a layer-by-layer manner at the catalyst/nanowire interface is evident. This study provides direct insights into the vapor-solid-solid growth and clarified the growth mechanism of <001[combining macron]> III-V nanowires, which provides pathways in controlling the growth of <001[combining macron]> semiconductor nanowires.

Foreign-catalyst-free GaSb nanowires directly grown on cleaved Si substrates by molecular-beam epitaxy

We have successfully fabricated foreign-catalyst-free GaSb nanowires directly on cleaved Si (111) substrates by molecular-beam epitaxy. We find that GaSb nanowires with the absence and presence of Ga droplets at the tip can be simultaneously obtained on cleaved Si substrates without Ga pre-deposition. Systematic morphological and structural studies verify that the two kinds of nanowires presented have different growth mechanisms, which are vapor-solid and vapor-liquid-solid mechanisms. The growth of GaSb nanowires can also be achieved on cleaved Si (110) and Si (100) substrates. The cleavage plane of the Si substrate has an obvious influence on the growth of the GaSb nanowires. The growth direction and crystal quality of catalyst-free nanowires are independent of the cleavage plane of the substrate. Our results may facilitate the understanding of the growth mechanism of III-V nanowires and the integration of foreign-catalyst-free GaSb nanowire-based devices with mature semiconductor technology.

Endogenous Retrovirus Activation as a Key Mechanism of Anti-Tumor Immune Response in Radiotherapy

The generation of DNA double-strand breaks has historically been taught as the mechanism through which radiotherapy kills cancer cells. Recently, radiation-induced cytosolic DNA release and activation of the cGAS/STING pathway, with ensuing induction of interferon secretion and immune activation, have been recognized as important mechanisms for radiation-mediated anti-tumor efficacy. Here we demonstrate that radiation-induced activation of endogenous retroviruses (ERVs) also plays a major role in regulating the anti-tumor immune response during irradiation. Radiation-induced ERV-associated dsRNA transcription and subsequent activation of the innate antiviral MDA5/MAVS/TBK1 pathway led to downstream transcription of interferon-stimulated genes. Additionally, genetic knockout of KAP1, a chromatin modulator responsible for suppressing ERV transcription sites within the genome, enhanced the effect of radiation-induced anti-tumor response in vivo in two different tumor models. This anti-tumor response was immune-mediated and required an intact host immune system. Our findings indicate that radiation-induced ERV-dsRNA expression and subsequent immune response play critical roles in clinical radiotherapy, and manipulation of epigenetic regulators and the dsRNA-sensing innate immunity pathway could be promising targets to enhance the efficacy of radiotherapy and cancer immunotherapy.

Effect of estradiol on penile erection: a cross-sectional study

Background

Past studies have shown that elevated estradiol levels could inhibit penile erection, but the relationship between estradiol and erection of the penile tip or base has not been extensively researched.

Methods

We therefore investigated estradiol's effects on the erection of the penile tip and base, with a cross-sectional study of 135 patients with erectile dysfunction (ED), based on scores of ≤21 according to the International Index of Erectile Function-5. All patients were tested for nocturnal penile tumescence, blood pressure (BP), serum glucose, total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PRL), progesterone (P), estradiol (E), and testosterone (T). Univariate and multivariate analyses were used to assess associations between estradiol levels and erection at the penile tip and base.

Results

We found no obvious relationship between erection time at penile tip and estradiol levels but did observe a negative correlation between base erection time and estradiol level [hazard ratio (HR): ‒0.11; 95% CI: ‒0.80-1.72]. With increasing estradiol concentration, multivariate analysis showed an obvious reduction in base erection time among patients with normal Rigiscan results (HR: ‒0.31; 95% CI: ‒1.63-1.29) (P<0.05) as estradiol concentration increased.

Conclusions

Our data indicate that estradiol inhibits penile erection, particularly at the penile base. Also, when the effective erection time of the penile base lasts longer than 10 min, estradiol has a more obvious inhibitory effect on penile base erection.

Autophagy regulates chemoresistance of gastric cancer stem cells via the Notch signaling pathway

OBJECTIVE

Gastric cancer is the most common gastrointestinal malignancy and the leading cause of cancer-related deaths in East Asia. Increasing evidence has revealed that autophagy is closely associated with tumor initiation and progression. The present work aimed to investigate the role of autophagy in adjuvant chemotherapy for gastric cancer.

MATERIALS AND METHODS

Gastric cancer stem cells (CSCs) were isolated from gastric cancer cell lines using the cell surface markers CD44 and CD54 and cultured in a three-dimensional cell culture system. Western blotting was used to detect their protein expression levels in gastric CSCs. In addition, the cells were treated with inhibitors to investigate the underlying mechanisms of autophagy.

RESULTS

After isolation of gastric CSCs expressing CD44 and CD54, Western blot analysis showed that the levels of the autophagic marker LC3II were markedly enhanced in CD44+CD54+ gastric CSCs. Moreover, the ratio of LC3II/LC3I protein levels was higher in CD44+CD54+ gastric CSCs than in non-CSCs. By contrast, both a chemotherapeutic agent (5-fluorouracil) and autophagy inhibitor (chloroquine) exhibited an inhibitory effect on the cell viability of gastric CSCs, and their combination further enhanced such inhibitory effects. Mechanistically, the addition of Notch inhibitor decreased the cell viability of gastric CSCs treated with 5-fluorouracil and chloroquine. In addition, 5-fluorouracil and chloroquine both increased the expression of Notch1 in gastric CSCs.

CONCLUSIONS

These findings show that autophagy regulated drug sensitivity of gastric cancer cells through the Notch signaling pathway.

Preliminary evaluation of GLP-1R PET in the diagnosis and risk stratification of pheochromocytomas

Noninvasive imaging methods for the diagnosis and risk stratification of pheochromocytomas (PHEOs) remain a great clinical challenge. The glucagon-like peptide-1 receptor (GLP-1R) has been validated to be overexpressed in PHEOs and therefore may be a reliable target for PHEOs. In this study, we firstly synthesized a novel radiotracer 68Ga-NOTA-MAL-Cys39-exendin-4 that specifically targets GLP-1R and evaluated the performance of GLP-1R PET for the diagnosis and risk stratification of PHEOs. Cys39-exendin-4 was conjugated to NOTA-MAL and then radiolabeled with 68Ga. The reaction was completed within 20 min with a yield of 91.6 ± 2.8%. In vitro cell uptake studies validated its high specificity. PET images showed promising tumor visualization with high uptake (1.88 ± 0.10 %ID/g for PC-12 poorly differentiated tumors and 1.09 ± 0.003 %ID/g for PC-12 highly differentiated tumors at 30min after injection). There was a significant difference in the uptake of 68Ga-NOTA-MAL-Cys39-exendin-4 between PC-12 poorly and highly differentiated tumors (p < 0.001), but no significant difference could be observed by 18F-FDG PET. Biodistribution results confirmed the findings of GLP-1R PET and demonstrated that 131I-MIBG couldn't be used for the risk stratification of PHEOs. Immunohistochemistry (IHC) staining revealed differences in GLP-1R expression between PC-12 poorly and highly differentiated tumor tissues. These results demonstrated that 68Ga-NOTA-MAL-Cys39-exendin-4 can specifically target GLP-1R with favorable pharmacokinetic properties. GLP-1R PET can be used for PHEOs detection and has potential for the risk stratification of PHEOs.

Vis-IR Wide-Spectrum Photodetector at Room Temperature Based on p-n Junction-Type GaAs1-xSbx/InAs Core-Shell Nanowire

Infrared (IR) detection at room temperature is very important in many fields. Nanoscale wide-spectrum photodetectors covering IR range are still rare, although they are desired in many applications, such as in integrated optoelectronic devices. Here, we report a new kind of photodetector based on p-n heterojunction-type GaAs_1-xSb_x/InAs core-shell nanowires. The photodetectors demonstrate high response to the lights ranging from visible light (488 nm) to short-wavelength IR (1800 nm) at room temperature under a very low bias voltage of 0.3 V. The high performance of the devices includes an ultralow dark current (32 pA at room temperature), a high response speed (0.45 ms) to 633 nm light, high responsivity to 1310 nm telecommunication light (0.12 A/W), high response even to 1800 nm light (on/off ratio of 2.5), etc. Besides, the devices also show excellent rectifying I-V characteristics (the current rectification ratio being ∼178 in a voltage range of ±0.3 V). These results suggest that the GaAs_1-xSb_x/InAs core-shell nanowire devices are promising for applications in nanoelectronic devices, optoelectronic devices, and integrated optoelectronic devices.

Effects of bisphenol A exposure on DNA integrity and protamination of mouse spermatozoa

BACKGROUND

Bisphenol A is widely used in the manufacture of polycarbonate plastics and has caused increasing concern over its potential adverse impacts on spermatogenesis. However, the effect of bisphenol A on spermiogenesis is yet to be explored.

OBJECTIVES

To evaluate whether bisphenol A has adverse effects on DNA integrity and protamination of spermatogenic cell.

MATERIALS AND METHODS

Newborn male mice were subcutaneously injected with bisphenol A (0.1, 5 mg/kg body weight, n = 15) or coin oil (control group, n = 20) daily from post-natal day 1 until 35. At post-natal day 70, epididymis caudal spermatozoa and testes were collected. Sperm count, sperm motility, and sperm morphology were analyzed. The sperm chromatin structure assay was performed to examine the sperm DNA fragmentation. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method was used to assess apoptosis of spermatogenic cells. The ultrastructural features of testicular sections were examined under a transmission electron microscope. Western blot and RT-PCR were used to detect the expression levels of transition protein (Tnp) 1 and Tnp2, protamine (Prm) 1 and Prm2 protein, and mRNA in mice testes.

RESULTS

Bisphenol A significantly reduced sperm counts, impaired sperm motility, and increased the percentage of malformed spermatozoa. Poor sperm chromatin integrity and increased TUNEL-positive spermatogenic cells were also observed in mice exposed to bisphenol A. Ultrastructural analysis of testes showed that bisphenol A exposure caused incomplete chromatin condensation, retention of residual cytoplasm, and abnormal acrosome formation. In addition, the relative expression levels of Tnp2 and Prm2 in mice testes decreased significantly in bisphenol A groups.

DISCUSSION AND CONCLUSION

Our findings identified that neonatal bisphenol A exposure may negatively contribute to the sperm quality in adult mice. Mechanistically, we showed that bisphenol A reduced sperm chromatin integrity along with increased DNA damage, which may be due to poor protamination of spermatozoa.

Activated Wnt/β-Catenin signaling contributes to E3 ubiquitin ligase EDD-conferred docetaxel resistance in prostate cancer

Docetaxel is commonly used to treat hormone-refractory prostate cancer (HRPC), but its clinical efficacy is limited by drug resistance, with the molecular mechanisms remaining elusive. The E3 ubiquitin ligase EDD modifies substrate proteins through ubiquitination and is involved in the regulation of cell proliferation and tumorigenesis. However, its role in docetaxel resistance of prostate cancer is unknown. Here, we show that EDD is upregulated in docetaxel-resistant HRPC cells, as well as in human HRPC treated with docetaxel chemotherapy. Functionally, EDD knockdown resensitizes HRPC cells to docetaxel in vitro and in vivo, and in reverse, EDD overexpression promotes docetaxel resistance. We further show that the Wnt/β-Catenin signaling is activated in docetaxel-resistant HRPC cells, which can be promoted by EDD. Finally, inhibiting Wnt signaling through β-Catenin knockdown remarkably attenuates EDD-mediated docetaxel resistance, suggesting that the activated Wnt/β-Catenin signaling is a key contributor to EDD-conferred docetaxel resistance in HRPC cells. Altogether, our study uncovers a positive role of EDD in docetaxel resistance in prostate cancer, and further links it with the regulation of Wnt/β-Catenin signaling.

Magnetic domains characterization of crystalline Fe3O4 under DC and AC magnetic field

Fe3O4 nanoparticles with crystallite sizes around 10 nm were synthesized by an emulsion method. X-ray diffractometer (XRD) shows that nanocrystalline Fe3O4 possesses face center cubic structure. The magnetic characteristics are investigated by magnetic force microscopy (MFM). Magnetic field directions were applied parallel and perpendicular to the Fe3O4 sample surface for magnetic measurements. Under the perpendicular magnetic field, the phase images of most magnetic nanoparticles exhibit bright or dark MFM contrast. In comparison, the parallel field phase images display a bright-dark dipole MFM contrast, with in-plane magnetic domain configurations. Furthermore, the investigation of strip domains inside Fe3O4 particles under altering magnetic fields indicates the existence of magnetic anisotropy energies, dipole energies as well as inter-grain coupling energies inside the clusters. This approach for probing magnetic responses on nanoscale magnetic domains can be further extended to the analysis of local physical features.

Simultaneously Enhanced Strength and Ductility of Al⁻Mg⁻Si Alloys during Aging Process Induced by Electro-Pulsing Treatment

Most methods used for strengthening metallic materials, such as thermal-mechanical treatment, will sacrifice the ductility. A novel technology, electric pulsing treatment (EPT), is applied to break this trade-off, which produces an Al–Mg–Si alloy with superior ductility and higher strength within only 560 ms. Systematic electron microscopy characterization and finite element simulation reveal that EPT promotes the formation of clusters Mg₂(Si,Cu)₃ and sub-grain boundaries. The results of quantitative calculation indicate that the dislocation entanglement is delayed due to the existence of clusters and longer dislocation glide distance, so that ultimate strength is fully improved. Moreover, the superior ductility is mainly governed by sub-grains which lead to higher mobile dislocation density, appearance of new crystal orientations, and prevention of crack propagation. Thereupon, this interesting finding paves the way in developing the Al–Mg–Si alloy with higher mechanical properties efficiently.

The targeting of MTDH by miR‑145‑5p or miR‑145‑3p is associated with prognosis and regulates the growth and metastasis of prostate cancer cells

Studies have rarely been conducted on the role of miRNAs in prostate cancer (PCa) cell progression by directly targeting MTDH, at least to the best of our knowledge. Thus, the present study aimed to identify miRNAs closely related with metadherin (MTDH) and to determine their roles in PCa. For this purpose, the expression levels of MTDH in PCa tissues and cell lines were examined by RT‑qPCR, immunohistochemistry and western blot analysis. By cell transfection, MTDH was either overexpressed in the normal prostate epithelial cell lines or silenced in tumor cell lines to determine cell viability, invasion and migration. Bioinformatics analysis, RT‑qPCR, western blot analysis, dual‑luciferase reporter assay and MTT assay were performed to identify direct the target of MTDH and to examine tumor cell viability. Rescue experiments using the PC‑3 and LNCaP cells were carried out by MTT assay, scratch wound assay, Transwell assay, RT‑qPCR and western blot analysis. Experiments were also conducted using 46 PCa human cancer and adjacent tissues, as wells as on 501 cases of PCa from the TCGA database. It was confirmed that the overexpression of MTDH was associated with a poor prognosis of patients. The overexpression of MTDH was found to promote the viability, invasion and migration of PCa cells. miR‑145‑5p and miR‑145‑3p identified from 16 miRNAs were found to be closely related to PCa and to be the targets of MTDH. Both these miRNAs were found to significantly suppress the growth and metastasis of PCa cells by negatively regulating the expression of MTDH. On the whole, the findings of this study demonstrate that MTDH functions as an oncogene in PCa and the inhibition of MTDH by miR‑145‑5p or miR‑145‑3p suppressed the growth and metastasis of PCa cells. The miR‑145‑5p/MTDH and miR‑145‑3p/MTDH pathways may thus become novel treatment targets for PCa.

Crossover from Coulomb blockade to ballistic transport in InAs nanowire devices

We report on the observation of a crossover from the single electron Coulomb blockade regime to the ballistic transport in individual InAs semiconducting nanowire devices. The InAs nanowires studied here were grown by molecular-beam epitaxy (MBE), which provides a clean system to study the intrinsic electrons transport in a quasi-one-dimensional system. Quantized conductance plateaus are observed for an InAs nanowire-based device by changing the Fermi level with a global back gate at low temperature, suggesting the ballistic transport of electrons. Further lowering the temperature, we observe the Coulomb blockade phenomenon with the formation of the quantum dot between the two normal metal contacts. By increasing the electron density, the characteristic Fabry-Pérot oscillations are observed, which further provides evidence for the ballistic nature of transport in the InAs nanowire device. Our observations indicate that high-quality InAs nanowires grown by MBE behave as clean quantum wires at low temperatures, which enables us to investigate novel phenomena in the quasi-one-dimensional system.

Dimension Engineering of High-Quality InAs Nanostructures on a Wafer Scale

Low-dimensional narrow-band-gap III-V semiconductors are key building blocks for the next generation of high-performance nanoelectronics, nanophotonics, and quantum devices. Realizing these various applications requires an efficient methodology that enables the material dimensional control during the synthesis process and the mass production of these materials with perfect crystallinity, reproducibility, low cost, and outstanding electronic and optoelectronic properties. Although advances in one- and two-dimensional narrow-band-gap III-V semiconductors synthesis, the progress toward reliable methods that can satisfy all of these requirements has been limited. Here, we demonstrate an approach that provides a precise control of the dimension of InAs from one-dimensional nanowires to wafer-scale free-standing two-dimensional nanosheets, which have a high degree of crystallinity and outstanding electrical and optical properties, using molecular-beam epitaxy by controlling catalyst alloy segregation. In our approach, two-dimensional InAs nanosheets can be obtained directly from one-dimensional InAs nanowires by silver-indium alloy segregation, which is much easier than the previously reported methods, such as the traditional buffering technique and select-area epitaxial growth. Detailed transmission electron microscopy investigations provide solid evidence that the catalyst alloy segregation is the origination of the InAs dimensional transformation from one-dimensional nanowires to two-dimensional nanosheets and even to three-dimensional complex crosses. Using this method, we find that the wafer-scale free-standing InAs nanosheets can be grown on various substrates including Si, MgO, sapphire, GaAs, etc. The InAs nanosheets grown at high temperature are pure-phase single crystals and have a high electron mobility and a long time-resolved terahertz kinetics lifetime. Our work will open up a conceptually new and general technology route toward the effective controlling of the dimension of the low-dimensional III-V semiconductors. It may also enable the low-cost fabrication of free-standing nanosheet-based devices on an industrial scale.