Nanomaterials-assisted gene editing and synthetic biology for optimizing the treatment of pulmonary diseases.

The use of nanomaterials in gene editing and synthetic biology has emerged as a pivotal strategy in the pursuit of refined treatment methodologies for pulmonary disorders. This review discusses the utilization of nanomaterial-assisted gene editing tools and synthetic biology techniques to promote the development of more precise and efficient treatments for pulmonary diseases. First, we briefly outline the characterization of the respiratory system and succinctly describe the principal applications of diverse nanomaterials in lung ailment treatment. Second, we elaborate on gene-editing tools, their configurations, and assorted delivery methods, while delving into the present state of nanomaterial-facilitated gene-editing interventions for a spectrum of pulmonary diseases. Subsequently, we briefly expound on synthetic biology and its deployment in biomedicine, focusing on research advances in the diagnosis and treatment of pulmonary conditions against the backdrop of the coronavirus disease 2019 pandemic. Finally, we summarize the extant lacunae in current research and delineate prospects for advancement in this domain. This holistic approach augments the development of pioneering solutions in lung disease treatment, thereby endowing patients with more efficacious and personalized therapeutic alternatives.

Senolytic Therapy Enabled by Senescent Cell-Sensitive Biomimetic Melanin Nano-Senolytics.

Cellular senescence is a significant risk factor for aging and age-related diseases (ARD). The canonical senolytics Dasatinib and Quercetin (DQ) have shown promise in clearing senescent cells (SnCs); however, the lack of selectivity poses a challenge in achieving optimal outcomes. Despite the recent occurrence of nanomaterial-based approaches targeting SnCs, limited therapeutic effects, and potential toxicity still remain a major concern. Herein, a "double locks-like" nanoplatform is developed that integrated Galactan coating and mesoporous polydopamine to encase the senolytic drug DQ. By this way, DQ is only released in SnCs that are featured with higher levels of ß-galactosidase (ß-gal) and low PH. Additionally, the nanoparticles are equipped with 2,2,6,6-Tetramethylpiperidine-1-oxyl (Tempo) to gain enhanced photothermal converting potential. Consequently, the synthesized nanosenolytics demonstrate remarkable specificity and efficacy in eradicating SnCs, and accordingly reverse pulmonary fibrosis in mice without affecting normal tissues. Upon exposure of near-infrared (NIR) light, the nanoparticles demonstrate to efficiently remove senescent tumor cells inducted by chemotherapy, thereby hindering the outgrowth and metastasis or breast cancer. Collectively, the present study develops an "On/Off" switchable nanoplatform in response to SnCs, and produces a more safe, efficient, and feasible way to delay aging or alleviate age-associated diseases.

Curcumin alleviates bisphenol AF-induced oxidative stress and apoptosis in caprine endometrial epithelial cells via the Nrf2 signaling pathway.

Bisphenol AF (BPAF), a BPA-substitute, has been widely used in industrial compounds throughout the world. Several studies have shown that BPAF has endocrine interference and reproductive toxicity. However, the toxic effects of BPAF on pregnancy and placenta of goats are still unclear. Therefore, the objective of this study was to reveal the toxic effect of BPAF by using an in vitro culture model of caprine endometrial epithelial cells (EECs) and further attempted to alleviate the toxicity by curcumin pretreatment. The results showed that BPAF induces significant effects on EECs, including decreased cell viability and mitochondrial membrane potential (△ψm), elevating intracellular reactive oxygen species (ROS), promoting cell apoptosis through upregulating the expression of Bax, Cytochrome c, and downregulating the expression of Bcl-2. Meanwhile, BPAF induced dysregulation of oxidative stress by increasing the levels of malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) but decreasing the activities of superoxide dismutase (SOD). However, curcumin pretreatment could significantly attenuate BPAF-induced toxic effects in EECs. Further study revealed that BPAF treatment could activate mitogen-activated protein kinase (MAPK) pathway and nuclear factor-erythroid 2-related factor 2 (Nrf2) expression, but curcumin pretreatment significantly inhibited the activation of MAPK signal pathway and Nrf2 expression induced by BPAF. Overall, this study indicated that curcumin could prevent BPAF-induced EECs cytotoxicity, which provides a potential therapeutic strategy for female infertility associated with BPAF exposure.

The Contributions of Trace Elements on Molecular Subtype-Specific Colorectal Cancer.

Purpose: Although growing studies have reported the disturbances of trace elements (TEs) homeostasis was closely associated with the occurrence of colorectal cancer (CRC), the clinical value of TEs in CRC with different molecular subtypes was largely unknown. This study aimed to explore the correlation between KRAS mutations/MSI status and serum TEs levels in patients with CRC. Methods: The serum concentrations of 18 TEs were detected by inductively coupled plasma emission spectrometry (ICP-MS). MSI status (two mononucleotides: BAT25, BAT26, three dinucleotides: D2S123, D5S346, and D17S250), KRAS (G516T, G517A, G518C, G520T, G521A, G522C, and G532A) mutations were detected by the multiplex fluorescent PCR and the real-time fluorescent quantitative PCR, respectively. The correlations among KRAS mutations/MSI status, demographic and clinical characteristics, and TEs were analyzed by Spearman correlation analysis. Results: The propensity score matching (PSM) analysis was adopted to minimize differences between groups. Before PSM, 204 CRC patients were recruited in this study, including 123 KRAS-negative patients and 81 KRAS-positive patients according to the test results of KRAS mutations, and 165 MSS patients and 39 MSI patients based on MSI detection. After PSM, the serum concentration of Mn was significantly lower in CRC patients with KRAS mutations than those without KRAS mutations, and a significant negative correlation was observed between Mn and Pb in the KRAS-positive cases. CRC patients carrying MSI had a significantly lower level of Rb compared to MSS patients. Importantly, Rb was significantly positively correlated with Fe, Mn, Se, and Zn in patients with MSI. Collectively, all our data indicated that the occurrence of different molecular events might be accompanied by different alterations in types and levels of serum TEs. Conclusions: CRC patients with different molecular subtypes presented different alterations in types and levels of serum TEs. Mn was significantly negatively correlated with the KRAS mutations, and Rb was noticeably negatively correlated with the MSI status, indicating certain TEs might contribute to the pathogenesis of molecular subtype-specific colorectal cancer.

Procedure-related pain during CT-guided percutaneous transthoracic needle biopsies of lung lesions: a prospective study.

BACKGROUND: The existing data on the degree of pain in patients during CT-guided percutaneous transthoracic needle biopsy (PTNB) of lung lesions are limited and the factors related to pain are unclear. In this study, we aimed to evaluate the prevalence and severity of pain reported during PTNB and to identify factors associated with increased reported pain. METHODS: Patients who underwent PTNB from April 2022 to November 2022 were prospectively evaluated using the numeric rating scale, which assesses subjective pain based on a 0-10 scoring system (0 = no pain; 10 = the worst pain imaginable). The scale divides the scores into three categories: mild pain (1-3 points), moderate pain (4-6 points), and severe pain (7-10 points). Pain scores from 4 to 10 were considered significant pain. Demographic data of patients, lesion characteristics, biopsy variables, complications, the patient's subjective feelings, and pathological result data were analyzed by multivariable logistic regression analysis to identify variables associated with significant pain. RESULTS: We enrolled 215 participants who underwent 215 biopsy procedures (mean age: 64.5 ± 9.3 years, 123 were men). The mean procedure-related pain score was 2 ± 2. Overall, 20% (43/215) of participants reported no pain (score of 0), 67.9% (146/215) reported pain scores of 1-3, 11.2% (24/215) reported scores of 4-6, and 0.9% (2/215) reported scores of 7 or higher. Furthermore, non-significant pain (scores of 0-3) was reported during 87.9% (189/215) of the procedures. In the adjusted model, significant pain was positively associated with lesions ≥ 34 mm (p = 0.001, odds ratio [OR] = 6.90; 95% confidence interval [CI]: 2.18, 21.85), a needle-pleural angle ≥ 77° (p = 0.047, OR = 2.44; 95% CI: 1.01, 5.89), and a procedure time ≥ 26.5 min (p = 0.031, OR = 3.11; 95% CI: 1.11, 8.73). CONCLUSIONS: Most participants reported no pain or mild pain from CT-guided percutaneous transthoracic needle biopsies of lung lesions. However, those with a larger lesion, a greater needle-pleural angle, and a longer procedure time reported greater pain.

Revisiting the Hetero-Interface of Electrolyte/2D Materials in an Electric Double Layer Device.

Electric double layer (EDL) devices based on 2D materials have made great achievements for versatile electronic and opto-electronic applications; however, the ion dynamics and electric field distribution of the EDL at the electrolyte/2D material interface and their influence on the physical properties of 2D materials have not been clearly clarified. In this work, by using Kelvin probe force microscope and steady/transient optical techniques, the character of the EDL and its influence on the optical properties of monolayer transition metal dichalcogenides (TMDs) are probed. The potential drop, unscreened EDL potential distribution, and accumulated carriers at the electrolyte/TMD interface are revealed, which can be explained by nonlinear Thomas-Fermi theory. By monitoring the potential distribution along the channel, the evolution of the electric field-induced lateral junction in the TMD EDL transistor is accessed, giving rise to the better exploration of EDL device physics. More importantly, EDL gate-dependent carrier recombination and exciton-exciton annihilation in monolayer TMDs on lithium-ion solid state electrolyte (Li2 Al2 SiP2 TiO13 ) are evaluated for the first time, benefiting from the understanding of the interaction between ions, carriers, and excitons. The work will deepen the understanding of the EDL for the exploitation of functional device applications.

Correlation between Toll-like Receptor Gene Polymorphisms and Idiopathic Nephrotic Syndrome in Chinese Children.

OBJECTIVE: Idiopathic nephrotic syndrome (INS) is the most common glomerular disease in children. Toll-like receptors (TLRs) have been reported to be associated with response to steroid treatment in children with INS. Nevertheless, the correlation between TLR genes and the progression of INS has not yet been clarified. The present study aimed to investigate the association of single-nucleotide polymorphisms (SNPs) in TLR2, TLR4, and TLR9 with susceptibility to INS as well as the clinical phenotyping of steroid responsiveness in Chinese children with INS. METHODS: A total of 183 pediatric inpatients with INS were included and given standard steroid therapy. Based on their clinical response to steroids, the patients were classified into three groups: steroid-sensitive nephrotic syndrome (SSNS), steroid-dependent nephrotic syndrome (SDNS), and steroid-resistant nephrotic syndrome (SRNS). A total of 100 healthy children were employed as controls. The blood genome DNA was extracted from each participant. Six SNPs (rs11536889, rs1927914, rs7869402, rs11536891, rs352140, and rs3804099) in TLR2, TLR4, and TLR9 were selected and detected by multiplex polymerase chain reaction with next-generation sequencing to assess TLR gene polymorphisms. RESULTS: Among the 183 patients with INS, 89 (48.6%) had SSNS, 73 (39.9%) had SDNS, and 21 (11.5%) had SRNS. No significant difference was found in the genotype distribution between healthy children and patients with INS. However, the genotype and allele frequencies of TLR4 rs7869402 were significantly different between SRNS and SSNS. Compared with patients with the C allele and CC genotype, patients with the T allele and CT genotype had an increased risk of SRNS. CONCLUSION: TLR4 rs7869402 affected the steroid response in Chinese children with INS. It might be a predictor for the early detection of SRNS in this population.

Cell Membranes from Tumor-Tropic MSCs Screened by a Microfluidic Chip for Drug Nanoparticles Encapsulation and Cancer Targeted Therapy.

Nanoparticles (NPs)-based drug carriers are effective in reducing systemic toxicity and drug resistance for chemotherapy, and an emerging trend focuses on integrating cell membranes with nanomedicines for tumor targeting. Mesenchymal stem cells (MSCs) are promising candidates due to their unique tropism toward cancer cells, yet the tumor-tropic abilities can differ for MSCs sourced from different tissues. Here, a multichannel microfluidic chip to screen different sourced MSCs with the greatest tropism toward cervical cancer cells is developed. Based on this, the cell membranes from the chorionic plate-derived MSC are isolated and membrane-camouflaged platinum prodrug composite NPs for cervical cancer treatment are prepared. Results demonstrate that the composite NPs can effectively target tumor sites and have a therapeutic effect both in vitro and in vivo. It is believed that the present microfluidic platform is a powerful tool for cell screening and tumor-on-a-chip studies, and the derived nanodelivery system represents the great value of cell membrane-camouflaged nanomedicine for targeted cancer therapy.

Acute exposure of triclocarban affects early embryo development in mouse through disrupting maternal-to-zygotic transition and epigenetic modifications.

Triclocarban (TCC) is a broad-spectrum antibacterial agent used globally, and high concentrations of this harmful chemical exist in the environment. The human body is directly exposed to TCC through skin contact. Moreover, TCC is also absorbed through diet and inhaled through breathing, which results in its accumulation in the body. The safety profile of TCC and its potential impact on human health are still not completely clear; therefore, it becomes imperative to evaluate the reproductive toxicity of TCC. Here, we explored the effect of TCC on the early embryonic development of mice and its associated mechanisms. We found that acute exposure of TCC affected the early embryonic development of mice in a dose-dependent manner. Approximately 7600 differentially expressed genes (DEGs) were obtained by sequencing the transcriptome of 2-cell mouse embryos; of these, 3157 genes were upregulated and 4443 genes were downregulated in the TCC-treated embryos. GO and KEGG analysis revealed that the enriched genes were mainly involved in redox processes, RNA synthesis, DNA damage, apoptosis, mitochondria, endoplasmic reticulum, Golgi apparatus, cytoskeleton, peroxisome, RNA polymerase, and other components or processes. Moreover, the Venn analysis showed that the zygotic genome activation (ZGA) was affected and the degradation of maternal effector genes was inhibited. TCC induced changes in the epigenetic modification of 2-cell embryos. The level of DNA methylation increased significantly. Further, the levels of H3K27ac, H3K9ac, and H3K27me3 histone modifications decreased significantly, whereas those of H3K4me3 and H3K9me3 modifications increased significantly. Additionally, TCC induced oxidative stress and DNA damage in the 2-cell embryos. In conclusion, acute exposure of TCC affected early embryo development, destroyed early embryo gene expression, interfered with ZGA and maternal gene degradation, induced changes in epigenetic modification of early embryos, and led to oxidative stress and DNA damage in mouse early embryos.

Coxsackievirus A6 was the most common enterovirus serotype causing hand, foot, and mouth disease in Shiyan City, central China.

BACKGROUND: Hand, foot, and mouth disease (HFMD) has become one of the most common infectious diseases in China. Before 2016, the primary causal serotypes were enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16). Following the introduction of EV-A71 vaccines in China since 2016, the situation could change. CV-A6 has recently replaced EV-A71 and CV-A16 in some areas of China. However, the epidemiological characteristics of central China remain unknown. AIM: To investigate the clinical symptoms and pathogen spectrum of HFMD in Shiyan City, central China, in recent years. METHODS: The epidemiological, clinical, and laboratory data from HFMD cases reported to the Shiyan Center for Disease Control and Prevention between January 2016 and December 2020 were analyzed. 196 throat swab specimens were collected from hospitalized HFMD patients between January 2018 and December 2020. To detect and genotype enteroviruses, real-time reverse transcription-polymerase chain reaction and sequencing of the 5'-untranslated region were used. In Shiyan, 168 laboratory-confirmed HFMD cases were studied using a logistic regression model to determine the effect of predominant enterovirus serotypes. Based on the logistic regression model, the least absolute shrinkage and selection operator model was used to analyze the correlation between CV-A6 infection and various clinical characteristics in HFMD patients in Shiyan. RESULTS: From 2016 to 2020, 35840 HFMD cases were reported in Shiyan. The number of cases decreased by 48.4% from 2016 to 2017. Approximately 1.58-fold increases were found in 2018 and 2019 when compared to the previous year, respectively. In 2020, a decrease of about 85.5% was reported when compared to 2019. The most common serotypes shifted from EV-A71 and CV-A16 (about 60%-80% in 2016 and 2018) to others (more than 80.0% in 2017, 2019, and 2020). EV-A71 lost its dominance in 2017 in Shiyan. Among 196 confirmed HFMD cases, 85.7% tested positive for enterovirus, with CV-A6 being the most common serotype (121/168, 72.0%). The positive rates for CV-A16 and CV-A10 were 4.8% and 3.0%, respectively. There was no EV-A71 discovered. Infection with CV-A6 was linked to fever, myocardial damage, increased creatine kinase MB isoenzyme, and lactate dehydrogenase levels. CONCLUSION: CV-A6 was the most common enterovirus serotype in Shiyan City, replacing EV-A71 and CV-A16 as the HFMD pathogen. Developing vaccines against CV-A6 or multiple pathogens, as well as rising CV-A6 surveillance, will help prevent HFMD in central China.

Doxorubicin loaded hydrogel microparticles from microfluidics for local injection therapy of tumors.

Doxorubicin (DOX) is a powerful chemotherapy drug for cancer treatment, especially in patients with advanced cancer. However, clinical use of DOX remains challenging due to its widespread drug resistance and severe cardiotoxicity. Here, we developed a novel DOX-loaded natural hydrogel microparticle by using microfluidic electrospray technology. The designed carboxymethyl cellulose-based hydrogel microparticles were cross-linked by iron ions and showed a sustained drug release. The animal experiments revealed that DOX-loaded microparticles had good biocompatibility when locally injected into tumor-bearing mice, and could enhance the effect of chemotherapy and effectively inhibit tumor growth without obvious toxicity. These features indicated that the natural biomass-based hydrogel microparticles are highly promising for chemotherapy drugs delivery and provide a platform for local therapy.

Bromoacetic acid impairs mouse oocyte in vitro maturation through affecting cytoskeleton architecture and epigenetic modification.

As a major public health achievement, disinfection of drinking water significantly decreases outbreaks of waterborne disease, but produces drinking water disinfection by-products (DBPs) unfortunately. The haloacetic acids (HAAs) including bromoacetic acid (BAA), the second major class of DBPs, are considered as a global public health concern. BAA has been identified as cytotoxic, genotoxic, mutagenic, carcinogenic, and teratogenic in somatic cells. However, the toxic effects of BAA on oocyte maturation remain obscure. Herein, we documented that exposure to BAA compromised mouse oocyte maturation in vitro, causing blocked polar body extrusion (PBE). Meiotic progression analysis demonstrated that exposure to BAA induced the activated spindle assembly checkpoint (SAC) mediated metaphase I (MI) arrest in oocytes. Further study revealed that exposure to BAA resulted in the hyperacetylation of α-tubulin, disrupting spindle assembly and chromosome alignment, which is responsible for the activation of SAC. Besides, the organization of actin, the other major component of cytoskeleton in oocytes, was disturbed after BAA exposure. In addition, exposure to BAA altered the status of histone H3 methylation and 5 mC, indicative of the damaged epigenetic modifications. Moreover, we found that exposure to BAA induced DNA damage in a dose-dependent manner in oocytes. Collectively, our study evidenced that exposure to BAA intervened mouse oocyte maturation via disrupting cytoskeletal dynamics, damaging epigenetic modifications and inducing accumulation of DNA damage.

[Spatial Characterization of Stable Isotope Composition of Organic Carbon from Farmland Soils in Chongqing].

Soil was sampled from 182 profiles in typical farmlands of Chongqing and analyzed for the stable carbon isotope composition of organic matter (δ13CSOC). The results showed that the values of δ13CSOC for each soil profile were gradually increasing with increasing soil depth, and the mean values were (-23.63±1.53)‰, (-22.43±1.59)‰, and (-21.42±1.90)‰ for surface, middle, and bottom layers, respectively. The δ13CSOC values in the northeastern region of Chongqing tended to be more negative, whereas those in central Chongqing were less negative. Paddy fields showed the most negative values of δ13CSOC, followed by rice-upland rotating fields and upland fields, with the average being (-25.32±0.93)‰, (-23.17±1.37)‰, and (-24.75±1.28)‰ for the surface layers, respectively. For different soil types, the δ13C values in the surface layers were in the order of paddy soil

Functional movement screen dataset collected with two Azure Kinect depth sensors.

This paper presents a dataset for vision-based autonomous Functional Movement Screen (FMS) collected from 45 human subjects of different ages (18-59 years old) executing the following movements: deep squat, hurdle step, in-line lunge, shoulder mobility, active straight raise, trunk stability push-up and rotary stability. Specifically, shoulder mobility was performed only once by different subjects, while the other movements were repeated for three episodes each. Each episode was saved as one record and was annotated from 0 to 3 by three FMS experts. The main strength of our database is twofold. One is the multimodal data provided, including color images, depth images, quaternions, 3D human skeleton joints and 2D pixel trajectories of 32 joints. The other is the multiview data collected from the two synchronized Azure Kinect sensors in front of and on the side of the subjects. Finally, our dataset contains a total of 1812 recordings, with 3624 episodes. The size of the dataset is 190 GB. This dataset provides the opportunity for automatic action quality evaluation of FMS.

Upcycling waste polyvinyl chloride: One-pot synthesis of valuable carbon materials and pipeline-quality syngas via pyrolysis in a closed reactor.

Polyvinyl chloride (PVC) is one of the most commonly used plastics. The treatment and recycling of PVC waste is still challenging, due to its non-biodegradability, low thermal stability, high Cl content and low product value. In this study, a one-pot method was developed to upcycle PVC into valuable carbon materials, pipeline-quality pyrolysis gas and chlorides. The well-designed process included dechlorination by Cl-fixative (ZnO or KOH), carbonization of dechlorinated polyenes, and modification of carbon materials in sequence. ZnO and KOH converted 84.48% and 94.15% of total Cl into corresponding chlorides, respectively. CH4 and H2 accounted for 81.87-99.34 vol% of pyrolysis gas with higher heat values of 30.11-32.84 MJ m-3, which can be used as substitute natural gas. As high as 83.13% of the C element was converted into carbon materials. The morphology, structure and property of carbon materials can be modified by different Cl-fixatives. Millimeter-scale carbon spheres with mono-dispersity and porous carbon with a high specific surface area of 1922 m2 g-1 were obtained when ZnO and KOH were added, respectively. Moreover, the reaction mechanisms of PVC with Cl-fixatives were also deciphered through thermogravimetric analysis and thermodynamic simulation.

Exosomal hsa-miR-129-2 and hsa-miR-889 from a 6-microRNA Signature Might be a Potential Biomarker for Predicting the Prognosis of Papillary Thyroid Carcinoma.

BACKGROUND: Papillary thyroid carcinoma (PTC) is a subtype of thyroid cancer with increasing incidence over time. OBJECTIVE: This study aimed to build a risk score (RS) system for PTC patients. METHODS: PTC microRNA (miRNA) and messenger RNA (mRNA) expression data were extracted from The Cancer Genome Atlas (TCGA) database. The 491 PTC samples were randomly divided into training and validation sets. Using the limma software package, differentially expressed mRNAs (DEGs) and miRNAs (DEMs) between the tumor and control groups were screened. In order to construct an RS system, a survival package was used to select independent miRNAs related to prognosis. Enrichment analysis was performed, and a miRNA-mRNA co-expression network was constructed. High-throughput sequencing was also used to verify the prognostic miRNAs in exosomes. RESULTS: We found 1363 DEGs and 171 DEMs between the tumor and control groups. After identifying 26 DEMs significantly related to prognosis, 6 independent prognosis-associated miRNAs were selected to build an RS system. The areas under the curves of the overall survival rates of the training, validation, and entire sets were 0.847, 0.772, and 0.819, respectively. By conducting pathway analysis using the miRNA-mRNA co-expression network, one overlapping factor and five overlapping pathways were obtained. In addition, high-throughput sequencing revealed that the hsa-miR-129-2, hsa-miR-548j, hsa-miR-6734, and hsa-miR-889 expression levels in TCGA tumor tissues and exosomes were consistent, and those of hsa-miR-129-2 and hsa-miR- 889 between patients and controls were significantly different in exosomes. CONCLUSION: The six-miRNA RS system in exosomes may comprise independent signatures for predicting PTC patient prognosis.

NKG2D discriminates diverse ligands through selectively mechano-regulated ligand conformational changes.

Stimulatory immune receptor NKG2D binds diverse ligands to elicit differential anti-tumor and anti-virus immune responses. Two conflicting degeneracy recognition models based on static crystal structures and in-solution binding affinities have been considered for almost two decades. Whether and how NKG2D recognizes and discriminates diverse ligands still remain unclear. Using live-cell-based single-molecule biomechanical assay, we characterized the in situ binding kinetics of NKG2D interacting with different ligands in the absence or presence of mechanical force. We found that mechanical force application selectively prolonged NKG2D interaction lifetimes with the ligands MICA and MICB, but not with ULBPs, and that force-strengthened binding is much more pronounced for MICA than for other ligands. We also integrated steered molecular dynamics simulations and mutagenesis to reveal force-induced rotational conformational changes of MICA, involving formation of additional hydrogen bonds on its binding interface with NKG2D, impeding MICA dissociation under force. We further provided a kinetic triggering model to reveal that force-dependent affinity determines NKG2D ligand discrimination and its downstream NK cell activation. Together, our results demonstrate that NKG2D has a discrimination power to recognize different ligands, which depends on selective mechanical force-induced ligand conformational changes.

Comparison of Radiation Dose and Image Quality Between Split-Filter Twin Beam Dual-Energy Images and Single-Energy Images in Single-Source Contrast-Enhanced Chest Computed Tomography.

OBJECTIVE: To compare image quality and radiation dose of split-filter TwinBeam dual-energy (SF-TBDE) with those of single-energy images (SECT) in the contrast-enhanced chest computed tomography (CT). METHODS: Two hundred patients who underwent SF-TBDE (n = 100) and SECT (n = 100) contrast-enhanced chest scanning were retrospectively analyzed. The contrast-to-noise ratio (CNR) and figure of merit (FOM)-CNR of 5 structures (lung, aorta, pulmonary artery, thyroid, and erector spinae) were calculated and subjectively evaluated by 2 independent radiologists. Radiation dose was compared using volume CT dose index and size-specific dose estimate. RESULTS: The CNR and FOM-CNR of lung and erector spinae in SF-TBDE were higher than those of SECT (P < 0.001). The differences in the subjective image quality between the 2 groups were not significant (P = 0.244). Volume CT dose index and size-specific dose estimate of SF-TBDE were lower than those of SECT (6.60 ± 1.56 vs 7.81 ± 3.02 mGy, P = 0.001; 9.25 ± 1.60 vs. 10.55 ± 3.54; P = 0.001). CONCLUSIONS: The SF-TBDE CT can provide similar image quality at a lower radiation dose compared with SECT.

ReaxFF-MPNN machine learning potential: a combination of reactive force field and message passing neural networks.

Reactive force field (ReaxFF) is a powerful computational tool for exploring material properties. In this work, we proposed an enhanced reactive force field model, which uses message passing neural networks (MPNN) to compute the bond order and bond energies. MPNN are a variation of graph neural networks (GNN), which are derived from graph theory. In MPNN or GNN, molecular structures are treated as a graph and atoms and chemical bonds are represented by nodes and edges. The edge states correspond to the bond order in ReaxFF and are updated by message functions according to the message passing algorithms. The results are very encouraging; the investigation of the potential, such as the potential energy surface, reaction energies and equation of state, are greatly improved by this simple improvement. The new potential model, called reactive force field with message passing neural networks (ReaxFF-MPNN), is provided as an interface in an atomic simulation environment (ASE) with which the original ReaxFF and ReaxFF-MPNN potential models can do MD simulations and geometry optimizations within the ASE. Furthermore, machine learning, based on an active learning algorithm and gradient optimizer, is designed to train the model. We found that the active learning machine not only saves the manual work to collect the training data but is also much more effective than the general optimizer.