The binding affinity-dependent inhibition of cell growth and viability by DNA sulfur-binding domains.

Increasing evidence suggests that DNA phosphorothioate (PT) modification serves several purposes in the bacterial host, and some restriction enzymes specifically target PT-DNA. PT-dependent restriction enzymes (PDREs) bind PT-DNA through their DNA sulfur binding domain (SBD) with dissociation constants (KD) of 5 nM~1 µM. Here, we report that SprMcrA, a PDRE, failed to dissociate from PT-DNA after cleavage due to high binding affinity, resulting in low DNA cleavage efficiency. Expression of SBDs in Escherichia coli cells with PT modification induced a drastic loss of cell viability at 25°C when both DNA strands of a PT site were bound, with one SBD on each DNA strand. However, at this temperature, SBD binding to only one PT DNA strand elicited a severe growth lag rather than lethality. This cell growth inhibition phenotype was alleviated by raising the growth temperature. An in vitro assay mimicking DNA replication and RNA transcription demonstrated that the bound SBD hindered the synthesis of new DNA and RNA when using PT-DNA as the template. Our findings suggest that DNA modification-targeting proteins might regulate cellular processes involved in DNA metabolism in addition to being components of restriction-modification systems and epigenetic readers.

Decreased brain iron deposition based on quantitative susceptibility mapping correlates with reduced neurodevelopmental status in children with autism spectrum disorder.

To investigate potential correlations between the susceptibility values of certain brain regions and the severity of disease or neurodevelopmental status in children with autism spectrum disorder (ASD), 18 ASD children and 15 healthy controls (HCs) were recruited. The neurodevelopmental status was assessed by the Gesell Developmental Schedules (GDS) and the severity of the disease was evaluated by the Autism Behavior Checklist (ABC). Eleven brain regions were selected as regions of interest and the susceptibility values were measured by quantitative susceptibility mapping. To evaluate the diagnostic capacity of susceptibility values in distinguishing ASD and HC, the receiver operating characteristic (ROC) curve was computed. Pearson and Spearman partial correlation analysis were used to depict the correlations between the susceptibility values, the ABC scores, and the GDS scores in the ASD group. ROC curves showed that the susceptibility values of the left and right frontal white matter had a larger area under the curve in the ASD group. The susceptibility value of the right globus pallidus was positively correlated with the GDS-fine motor scale score. These findings indicated that the susceptibility value of the right globus pallidus might be a viable imaging biomarker for evaluating the neurodevelopmental status of ASD children.

Characterization of a promiscuous DNA sulfur binding domain and application in site-directed RNA base editing.

Phosphorothioate (PT)-modification was discovered in prokaryotes and is involved in many biological functions such as restriction-modification systems. PT-modification can be recognized by the sulfur binding domains (SBDs) of PT-dependent restriction endonucleases, through coordination with the sulfur atom, accompanied by interactions with the DNA backbone and bases. The unique characteristics of PT recognition endow SBDs with the potential to be developed into gene-targeting tools, but previously reported SBDs display sequence-specificity for PT-DNA, which limits their applications. In this work, we identified a novel sequence-promiscuous SBDHga from Hahella ganghwensis. We solved the crystal structure of SBDHga complexed with PT-DNA substrate to 1.8 Å resolution and revealed the recognition mechanism. A shorter L4 loop of SBDHga interacts with the DNA backbone, in contrast with previously reported SBDs, which interact with DNA bases. Furthermore, we explored the feasibility of using SBDHga and a PT-oligonucleotide as targeting tools for site-directed adenosine-to-inosine (A-to-I) RNA editing. A GFP non-sense mutant RNA was repaired at about 60% by harnessing a chimeric SBD-hADAR2DD (deaminase domain of human adenosine deaminase acting on RNA), comparable with currently available RNA editing techniques. This work provides insights into understanding the mechanism of sequence-specificity for SBDs and for developing new tools for gene therapy.

The FBXW7-binding sites on FAM83D are potential targets for cancer therapy.

Increasing evidence shows the oncogenic function of FAM83D in human cancer, but how FAM83D exerts its oncogenic function remains largely unclear. Here, we investigated the importance of FAM83D/FBXW7 interaction in breast cancer (BC). We systematically mapped the FBXW7-binding sites on FAM83D through a comprehensive mutational analysis together with co-immunoprecipitation assay. Mutations at the FBXW7-binding sites on FAM83D led to that FAM83D lost its capability to promote the ubiquitination and proteasomal degradation of FBXW7; cell proliferation, migration, and invasion in vitro; and tumor growth and metastasis in vivo, indicating that the FBXW7-binding sites on FAM83D are essential for its oncogenic functions. A meta-evaluation of FAM83D revealed that the prognostic impact of FAM83D was independent on molecular subtypes. The higher expression of FAM83D has poorer prognosis. Moreover, high expression of FAM83D confers resistance to chemotherapy in BCs, which is experimentally validated in vitro. We conclude that identification of FBXW7-binding sites on FAM83D not only reveals the importance for FAM83D oncogenic function, but also provides valuable insights for drug target.

Iron/Molybdenum Sulfide Nanozyme Cocatalytic Fenton Reaction for Photothermal/Chemodynamic Efficient Wound Healing.

The issue of bacterial infectious diseases remains a significant concern worldwide, particularly due to the misuse of antibiotics, which has caused the emergence of antibiotic-resistant strains. Fortunately, the rapid development of nanomaterials has propelled significant progress in antimicrobial therapy, offering promising solutions. Among them, the utilization of nanoenzyme-based chemodynamic therapy (CDT) has become a highly hopeful approach to combating bacterial infectious diseases. Nevertheless, the application of CDT appears to be facing certain constraints for its low efficiency in the Fenton reaction at the infected site. In this study, we have successfully synthesized a versatile nanozyme, which was a composite of molybdenum sulfide (MoS2) and iron sulfide (FeS2), through the hydrothermal method. The results showed that iron/molybdenum sulfide nanozymes (Fe/Mo SNZs) with desirable peroxidase (POD) mimic activity can generate cytotoxic reactive oxygen species (ROS) by successfully triggering the Fenton reaction. The presence of MoS2 significantly accelerates the conversion of Fe2+/Fe3+ through a cocatalytic reaction that involves the participation of redox pairs of Mo4+/Mo6+, thereby enhancing the efficiency of CDT. Additionally, based on the excellent photothermal performance of Fe/Mo SNZs, a near-infrared (NIR) laser was used to induce localized temperature elevation for photothermal therapy (PTT) and enhance the POD-like nanoenzymatic activity. Notably, both in vitro and in vivo results demonstrated that Fe/Mo SNZs with good broad-spectrum antibacterial properties can help eradicate Gram-negative bacteria like Escherichia coli and Gram-positive bacteria like Staphylococcus aureus. The most exciting thing is that the synergistic PTT/CDT exhibited astonishing antibacterial ability and can achieve complete elimination of bacteria, which promoted wound healing after infection. Overall, this study presents a synergistic PTT/CDT strategy to address antibiotic resistance, providing avenues and directions for enhancing the efficacy of wound healing treatments and offering promising prospects for further clinical use in the near future.

Cobalt-Catalyzed Borylative Reduction of Azobenzenes to Hydrazobenzenes via a Diborylated-Hydrazine Intermediate.

Cobalt-catalyzed borylative reduction of azobenzenes using pinacolborane is developed. The simple cobalt chloride catalyst and reaction conditions make this protocol attractive for hydrazobenzene synthesis. This borylative reduction shows good functional group compatibility and can be readily scaled up to the gram scale. Preliminary mechanistic studies clarified the proton source of the hydrazine products. This cobalt-catalyzed azobenzene borylative reaction provides a practical protocol to prepare synthetically useful diborylated hydrazines.

Nintedanib could potentially lead to improvements in anti-melanoma differentiation-associated 5 dermatomyositis-associated interstitial lung disease.

OBJECTIVES: To determine the efficacy and safety of nintedanib in patients with anti-melanoma differentiation-associated gene 5 antibody positive dermatomyositis-associated interstitial lung disease (anti-MDA5+ DM-ILD). METHODS: The study was a retrospective cohort design that evaluated patients with anti-MDA5+ DM who either received or did not receive nintedanib. Clinical symptoms, laboratory tests, and survival were compared in the two groups using a propensity score-matched analysis. The primary endpoint was mortality, while adverse events were recorded descriptively. RESULTS: After propensity score matching, 14 patients who received nintedanib (nintedanib+ group) and matched 56 patients who did not receive nintedanib (nintedanib- group) were enrolled. Compared with the nintedanib- group, the nintedanib+ group had a lower incidence of heliotrope and arthritis, higher lymphocyte counts, lower serum ferritin levels, and greater 12-month survival (all p<0.005). Although lung function, HRCT score, and lung VAS were not statistically different between the two groups, the longitudinal study showed significant improvement in HRCT scores (p=0.028) and pulmonary VAS (p=0.019) in the nintedanib+ group. Adverse events occurred in 28.6% of patients, with the most common adverse event with nintedanib being diarrhoea. CONCLUSIONS: Nintedanib may be effective for improving clinical symptoms, laboratory parameters, lung lesions, and survival in anti-MDA5+ DM. Diarrhoea was the most common adverse event associated with nintedanib, although the drug was well tolerated by most patients.

Drug-coated balloon in the treatment of coronary artery de-novo large lesions angiography.

The superiority of drug-coated balloon (DCB) in treating small vessels, branching lesions, and high-risk bleeding lesions in coronary heart disease patients has been confirmed. However, its safety and efficacy in large vessels are still unclear. We aimed to investigate whether the efficacy of DCB in large vessels is not inferior to that of drug-eluting stent (DES). From November 2019 to April 2022, a total of 88 patients in our hospital who underwent coronary angiography for the first time and decided to receive DCB or DES treatment were selected. Indicators including late lumen loss (LLL), major adverse cardiovascular event (MACE) rate, major bleeding and all-cause mortality were evaluated at 9 months and 1-year post percutaneous coronary intervention (PCI) therapy. The primary endpoint of 9-month LLL was -0.07 in the DCB group and 0.19 mm in the DES group (p value＜0.001). 1-year cumulative MACE rates were similar in the DCB and DES groups (3.03% vs. 7.23%, P=0.519), TLR rates were similar (3.03% vs. 7.23%, P=0.519), Major bleeding was similar (3.03% vs. 5.45%, P=0.580), and 1 case of Cardiac death in DES group. For LLL, the DCB-only strategy was non-inferior to DES in treating de novo large lesions in the coronary arteries. Furthermore, the efficacy of DCB was comparable to DES at 1 year of follow-up for secondary clinical endpoints.

Serum uric acid predicts therapeutic response to midodrine hydrochloride in children with vasovagal syncope: a pilot study.

Serum uric acid (UA) level has been proven to be related to several cardiovascular and metabolic diseases. In the present study, we examined if baseline serum UA level could predict the therapeutic efficacy of midodrine hydrochloride on vasovagal syncope (VVS) in children. The pediatric VVS patients who received midodrine hydrochloride from November 2008 to October 2022 were enrolled. After a median treatment duration of 3 months, the therapeutic effect was evaluated. According to the patients' responses to midodrine hydrochloride, which was determined by the recurrence of syncope, they were divided into effective and ineffective groups. The baseline variables were explored using univariable and multivariate logistic analysis. The predictive efficacy was assessed by receiver operating characteristic curve (ROC), precision-recall curve (PR), Hosmer-Lemeshow test, calibration curve, and decision curve analysis (DCA). Totally, 53 participants were included in the study. Among the 51 patients who were successfully followed up, 29 (56.9%) responded to midodrine hydrochloride (effective group), and the other 22 (43.1%) failed to respond to midodrine hydrochloride (ineffective group). The participants in effective group had lower baseline serum UA level than those in ineffective group (276.5 ± 73 µmol/L vs. 332.7 ± 56 µmol/L, p = 0.004). Multivariable logistic analysis showed that serum UA was associated with the therapeutic response (odds ratio (OR): 0.985, 95% confidence interval (CI): 0.974-0.997, p = 0.01). ROC analysis indicated that using baseline serum UA < 299 µmol/L as a threshold value yielded a sensitivity of 77.3% and a specificity of 79.3% in predicting the treatment response to midodrine hydrochloride. The area under the PR curve was 0.833. Hosmer-Lemeshow test yielded a p value of 0.58, and calibration plot indicated that the model was well-fitted. DCA demonstrated that treatment decision depending on the baseline serum UA level resulted in a favorable net benefit.   Conclusion: This pilot study suggested that the baseline serum UA level could be taken as a predictor of therapeutic effect of midodrine hydrochloride on VVS in children. What is Known: • Empirical and unselected use of midodrine hydrochloride has an unfavorable therapeutic effect on VVS in children. Serum uric acid (UA) is closely linked to cardiovascular events. What is New: • A low baseline serum UA level successfully predicts the therapeutic effectiveness of midodrine hydrochloride on VVS in children.

Cyclic stretching combined with cell-cell adhesion is sufficient for inducing cell intercalation.

Although the important role of cell intercalation within a collective has long been recognized particularly for morphogenesis, the underlying mechanism remains poorly understood. Here we investigate the possibility that cellular responses to cyclic stretching play a major role in this process. By applying synchronized imaging and cyclic stretching to epithelial cells cultured on micropatterned polyacrylamide (PAA) substrates, we discovered that uniaxial cyclic stretching induces cell intercalation along with cell shape change and cell-cell interfacial remodeling. The process involved intermediate steps as previously reported for cell intercalation during embryonic morphogenesis, including the appearance of cell vertices, anisotropic vertex resolution, and directional expansion of cell-cell interface. Using mathematical modeling, we further found that cell shape change in conjunction with dynamic cell-cell adhesions was sufficient to account for the observations. Further investigation with small-molecule inhibitors indicated that disruption of myosin II activities suppressed cyclic stretching-induced intercalation while inhibiting the appearance of oriented vertices. Inhibition of Wnt signaling did not suppress stretch-induced cell shape change but disrupted cell intercalation and vertex resolution. Our results suggest that cyclic stretching, by inducing cell shape change and reorientation in the presence of dynamic cell-cell adhesions, can induce at least some aspects of cell intercalation and that this process is dependent in distinct ways on myosin II activities and Wnt signaling.

Nuclear Receptor NR1D1 Regulates Abdominal Aortic Aneurysm Development by Targeting the Mitochondrial Tricarboxylic Acid Cycle Enzyme Aconitase-2.

BACKGROUND: Metabolic disorder increases the risk of abdominal aortic aneurysm (AAA). NRs (nuclear receptors) have been increasingly recognized as important regulators of cell metabolism. However, the role of NRs in AAA development remains largely unknown. METHODS: We analyzed the expression profile of the NR superfamily in AAA tissues and identified NR1D1 (NR subfamily 1 group D member 1) as the most highly upregulated NR in AAA tissues. To examine the role of NR1D1 in AAA formation, we used vascular smooth muscle cell (VSMC)-specific, endothelial cell-specific, and myeloid cell-specific conditional Nr1d1 knockout mice in both AngII (angiotensin II)- and CaPO4-induced AAA models. RESULTS: Nr1d1 gene expression exhibited the highest fold change among all 49 NRs in AAA tissues, and NR1D1 protein was upregulated in both human and murine VSMCs from AAA tissues. The knockout of Nr1d1 in VSMCs but not endothelial cells and myeloid cells inhibited AAA formation in both AngII- and CaPO4-induced AAA models. Mechanistic studies identified ACO2 (aconitase-2), a key enzyme of the mitochondrial tricarboxylic acid cycle, as a direct target trans-repressed by NR1D1 that mediated the regulatory effects of NR1D1 on mitochondrial metabolism. NR1D1 deficiency restored the ACO2 dysregulation and mitochondrial dysfunction at the early stage of AngII infusion before AAA formation. Supplementation with αKG (α-ketoglutarate, a downstream metabolite of ACO2) was beneficial in preventing and treating AAA in mice in a manner that required NR1D1 in VSMCs. CONCLUSIONS: Our data define a previously unrecognized role of nuclear receptor NR1D1 in AAA pathogenesis and an undescribed NR1D1-ACO2 axis involved in regulating mitochondrial metabolism in VSMCs. It is important that our findings suggest αKG supplementation as an effective therapeutic approach for AAA treatment.

Silencing of CD147 inhibits cell proliferation, migration, invasion, lipid metabolism dysregulation and promotes apoptosis in lung adenocarcinoma via blocking the Rap1 signaling pathway.

OBJECTIVE: CD147 is an important glycoprotein that participates in the progression of diverse cancers. This study aims to explore the specific function of CD147 in lung adenocarcinoma (LUAD) and to reveal related downstream molecular mechanisms. METHODS: Followed by silencing of CD147, the viability, migration, invasion, and apoptosis of LUAD cells were measured by CCK8, wound healing, transwell assay, and flow cytometer, respectively. The expression of CD147 and two markers of lipid metabolism (FASN and ACOX1) were detected by qRT-PCR. A xenograft tumor model was constructed to investigate the function of CD147 in vivo. Then transcriptome sequencing was performed to explore the potential mechanisms. After measuring the expression of Rap1 and p-p38 MAPK/p38 MAPK by western blot, the changes of CD147 and lipid metabolism markers (FASN, ACOX1) was detected by Immunohistochemistry. Moreover, a Rap1 activator and a Rap1 inhibitor were applied for feedback functional experiments. RESULTS: CD147 was up-regulated in LUAD cells, and its silencing inhibited cell proliferation, migration, invasion, lipid metabolism dysregulation and promoted apoptosis, while overexpression of CD147 showed the opposite results. Silencing of CD147 also inhibited the growth of tumor xenografts in mice. Transcriptome sequencing revealed 834 up-regulated differentially expressed genes (DEGs) and 602 down-regulated DEGs. After functional enrichment, the Rap1 signaling pathway was selected as a potential target, which was then verified to be blocked by CD147 silencing. In addition, the treatment of Rap1 activator weakened the inhibiting effects of si-CD147 on the proliferation, migration, invasion, and lipid metabolism in LUAD cells, while the intervention of RAP1 inhibitor showed the opposite results. CONCLUSIONS: Silencing of CD147 inhibited the proliferation, migration, invasion, lipid metabolism dysregulation and promoted apoptosis of LUAD cells through blocking the Rap1 signaling pathway.

Stent Graft vs Drug-Coated Balloon in Endovascular Treatment of Complex Femoropopliteal Artery Lesions: A 2-Center Experience.

OBJECTIVE: Both stent grafts (SG) and drug-coated balloons (DCBs) have shown to be effective treatments for long and complex femoropopliteal (FP) lesions. However, there has not been a clinical trial comparing the 2 treatments directly. This study aims to compare the primary patency (PP) and clinical outcomes of SG and DCB for endovascular treatment of complex FP Trans-Atlantic Inter-Society Consensus (TASC) C/D lesions in patients. METHODS: From July 2013 to May 2019, a retrospective study was conducted at 2 medical centers to compare the clinical outcomes of Viabahn SG and DCB angioplasty in patients with TASC C/D FP lesions. The study used overlap weighting to adjust for differences in baseline characteristics and to reduce the impact of confounding factors and selection bias between the 2 groups. The primary endpoint was PP through 24 months, and the secondary endpoints included freedom from clinical-driven target lesion revascularization (CD-TLR), all-cause of death rate, and major amputation rate. RESULTS: A total of 161 limbs in 150 patients with TASC C/D FP lesions were treated either with Viabahn SGs (67 limbs, 65 patients) or DCBs (94 limbs, 85 patients). In the DCB group, 22 target vessels (23.4%) underwent directional atherectomy before DCB angioplasty and 37 target vessels (39.4%) underwent bail-out bare-metal stent implantation for early recoil or severe dissection. The SG group had significantly higher PP rates at both the 12 and 24 months than in the DCB group (75.8% vs 39.2%, p=0.02; 64.1% vs 31.9%, p=0.02), respectively. However, there were no significant differences between the 2 groups in terms of CD-TLR, death rate, and major amputation rate. According to the results of multivariate analysis, DCB angioplasty was the only independent predictor associated with restenosis (hazard ratio [HR]=0.264, 95% confidence interval [CI]=0.100-0.696, p=0.007). CONCLUSIONS: This study showed that SG was associated with a significantly higher PP rate in complex long FP lesions compared with DCB angioplasty. However, there was no significant difference in the freedom from CD-TLR and major amputation rate. It is important to follow the criteria for using SG strictly to avoid early restenosis, which can lead to acute thrombosis and severe limb ischemia. Closer monitoring is recommended for patients who undergo SG implantation. CLINICAL IMPACT: There has no head-to-head clinical trial that compares DCB and SG in complex long FP lesions. This study showed that SG following the criteria was associated with a significantly higher PP rate compared with DCB angioplasty. Closer monitoring is recommended for patients with SG to avoid acute thrombosis. Randomized controlled trials comparing SG and DCB are necessary.

A catalytic hairpin assembly-based Förster resonance energy transfer sensor for ratiometric detection of ochratoxin A in food samples.

Ochratoxin A (OTA) poses severe risks to the environment and human health, making the development of an accurate and sensitive analytical method for OTA detection essential. In this study, a catalytic hairpin assembly (CHA)-based Förster resonance energy transfer (FRET) aptasensor was developed to detect OTA using carbon quantum dots (CDs) and 6-carboxy-fluorescein (FAM) as dual signal readout. In the presence of OTA, the aptamer specifically interacted with OTA to release the helper DNA (HP), which could open the hairpin structure of FAM-labeled hairpin DNA 1 (H1-FAM) modified on the surface of gold nanoparticles (AuNPs). CHA between H1-FAM and hairpin H2 labeled with CDs (H2-CDs) can release HP for the next cycle, resulting in the occurrence of FRET with CDs as the energy donor and FAM as the energy acceptor. According to the ratio of FCDs/FFAM, the proposed aptasensor showed a wide linear range from 5.0 pg/mL to 3.0 ng/mL and a low detection limit of 1.5 pg/mL for OTA detection. Moreover, satisfactory results were obtained for OTA detection in rice, suggesting the potential application of this sensor in food safety analysis.

Unveiling breast cancer risk profiles: a survival clustering analysis empowered by an online web application.

Aim: To develop a shiny app for doctors to investigate breast cancer treatments through a new approach by incorporating unsupervised clustering and survival information. Materials & methods: Analysis is based on the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) dataset, which contains 1726 subjects and 22 variables. Cox regression was used to identify survival risk factors for K-means clustering. Logrank tests and C-statistics were compared across different cluster numbers and Kaplan-Meier plots were presented. Results & conclusion: Our study fills an existing void by introducing a unique combination of unsupervised learning techniques and survival information on the clinician side, demonstrating the potential of survival clustering as a valuable tool in uncovering hidden structures based on distinct risk profiles.

Design, synthesis, X-ray crystal structure, and antimicrobial evaluation of novel quinazolinone derivatives containing the 1,2,4-triazole Schiff base moiety and an isopropanol linker.

A series of novel quinazolinone derivatives (E1-E31) containing the 1,2,4-triazole Schiff base moiety and an isopropanol linker were designed, synthesized and assessed as antimicrobial agents in agriculture. All the target compounds were fully characterized by 1 H NMR, 13 C NMR, and high-resolution mass spectrometry (HRMS). Among them, the structure of compound E12 was further confirmed via single crystal X-ray diffraction method. The experimental results indicated that many compounds displayed good in vitro antibacterial efficacies against the tested phytopathogenic bacteria including Xanthomonas oryzae pv. oryzae (Xoo), Xanthomonas axonopodis pv. citri (Xac), and Ralstonia solanacearum (Rs). For example, compounds E3, E4, E10, E13, and E22 had EC50 (half-maximal effective concentration) values of 55.4, 39.5, 49.5, 53.5, and 57.4 µg/mL against Xoo, respectively, superior to the commercialized bactericide Bismerthiazol (94.5 µg/mL). In addition, the antibacterial efficacies of compounds E10 and E13 against Xac were about two times more effective than control Bismerthiazol, in terms of their EC50 values. Last, the antifungal assays showed that compounds E22 and E30 had the inhibition rates of 52.7% and 54.6% at 50 µg/mL against Gibberella zeae, respectively, higher than the commercialized fungicide Hymexazol (48.4%).

User Pairing for Delay-Limited NOMA-Based Satellite Networks with Deep Reinforcement Learning.

In this paper, we investigate a user pairing problem in power domain non-orthogonal multiple access (NOMA) scheme-aided satellite networks. In the considered scenario, different satellite applications are assumed with various delay quality-of-service (QoS) requirements, and the concept of effective capacity is employed to characterize the effect of delay QoS limitations on achieved performance. Based on this, our objective was to select users to form a NOMA user pair and utilize resource efficiently. To this end, a power allocation coefficient was firstly obtained by ensuring that the achieved capacity of users with sensitive delay QoS requirements was not less than that achieved with an orthogonal multiple access (OMA) scheme. Then, considering that user selection in a delay-limited NOMA-based satellite network is intractable and non-convex, a deep reinforcement learning (DRL) algorithm was employed for dynamic user selection. Specifically, channel conditions and delay QoS requirements of users were carefully selected as state, and a DRL algorithm was used to search for the optimal user who could achieve the maximum performance with the power allocation factor, to pair with the delay QoS-sensitive user to form a NOMA user pair for each state. Simulation results are provided to demonstrate that the proposed DRL-based user selection scheme can output the optimal action in each time slot and, thus, provide superior performance than that achieved with a random selection strategy and OMA scheme.

DaylilyNet: A Multi-Task Learning Method for Daylily Leaf Disease Detection.

Timely detection and management of daylily diseases are crucial to prevent yield reduction. However, detection models often struggle with handling the interference of complex backgrounds, leading to low accuracy, especially in detecting small targets. To address this problem, we propose DaylilyNet, an object detection algorithm that uses multi-task learning to optimize the detection process. By incorporating a semantic segmentation loss function, the model focuses its attention on diseased leaf regions, while a spatial global feature extractor enhances interactions between leaf and background areas. Additionally, a feature alignment module improves localization accuracy by mitigating feature misalignment. To investigate the impact of information loss on model detection performance, we created two datasets. One dataset, referred to as the 'sliding window dataset', was obtained by splitting the original-resolution images using a sliding window. The other dataset, known as the 'non-sliding window dataset', was obtained by downsampling the images. Experimental results in the 'sliding window dataset' and the 'non-sliding window dataset' demonstrate that DaylilyNet outperforms YOLOv5-L in mAP@0.5 by 5.2% and 4.0%, while reducing parameters and time cost. Compared to other models, our model maintains an advantage even in scenarios where there is missing information in the training dataset.

Fusion extracted features from deep learning for identification of multiple positioning errors in dental panoramic imaging.

BACKGROUND: Dental panoramic imaging plays a pivotal role in dentistry for diagnosis and treatment planning. However, correctly positioning patients can be challenging for technicians due to the complexity of the imaging equipment and variations in patient anatomy, leading to positioning errors. These errors can compromise image quality and potentially result in misdiagnoses. OBJECTIVE: This research aims to develop and validate a deep learning model capable of accurately and efficiently identifying multiple positioning errors in dental panoramic imaging. METHODS AND MATERIALS: This retrospective study used 552 panoramic images selected from a hospital Picture Archiving and Communication System (PACS). We defined six types of errors (E1-E6) namely, (1) slumped position, (2) chin tipped low, (3) open lip, (4) head turned to one side, (5) head tilted to one side, and (6) tongue against the palate. First, six Convolutional Neural Network (CNN) models were employed to extract image features, which were then fused using transfer learning. Next, a Support Vector Machine (SVM) was applied to create a classifier for multiple positioning errors, using the fused image features. Finally, the classifier performance was evaluated using 3 indices of precision, recall rate, and accuracy. RESULTS: Experimental results show that the fusion of image features with six binary SVM classifiers yielded high accuracy, recall rates, and precision. Specifically, the classifier achieved an accuracy of 0.832 for identifying multiple positioning errors. CONCLUSIONS: This study demonstrates that six SVM classifiers effectively identify multiple positioning errors in dental panoramic imaging. The fusion of extracted image features and the employment of SVM classifiers improve diagnostic precision, suggesting potential enhancements in dental imaging efficiency and diagnostic accuracy. Future research should consider larger datasets and explore real-time clinical application.

Human 2D Crypt Model for Assaying Intestinal Stem Cell Proliferation and Differentiation.

Intestine is a common site of adverse drug effects in clinical trials; thus, improved in vitro models for preclinical screening of pharmaceutical compounds are sought. A planar, self-renewing human intestinal monolayer platform based on primary adult gastrointestinal stem cells, termed the 2D crypt model, has been developed to screen for the effects of various compounds on the intestinal epithelium. The 2D crypt platform is based on a standard 12-well plate format and consists of cell culture inserts with a collagen film overlaying an impermeable film patterned with an array of micron-scale holes. This two-chamber format enables a gradient of growth factors to be applied such that the tissue self-organizes into spatially segregated stem and differentiated cell compartments. The patterned monolayer mimics a gut epithelium in possessing a stem cell niche, migrating proliferative and differentiated cells. Once established, the 2D crypts replicate many aspects of in vivo physiology, including cell migration, maturation, and apoptotic cell death. The planar geometry of the system simplifies dosing, sampling, and imaging during assay. An immunofluorescence-based assay was established to quantitatively assess cell density, proliferation, migration, viability, and the abundance and localization of postmitotic lineages as a function of time. The model was used to perform a small-scale screen of compounds, including signaling molecules, endogenous hormones/cytokines, and microbial metabolites, on tissue homeostasis. Hit compounds that significantly impacted proliferation and/or differentiation were readily identified. The 2D crypt platform represents a significant innovation in the development of microphysiological systems for emulating the gut epithelium for compound screens.