Mesoscale DNA feature in antibody-coding sequence facilitates somatic hypermutation.

Somatic hypermutation (SHM), initiated by activation-induced cytidine deaminase (AID), generates mutations in the antibody-coding sequence to allow affinity maturation. Why these mutations intrinsically focus on the three nonconsecutive complementarity-determining regions (CDRs) remains enigmatic. Here, we found that predisposition mutagenesis depends on the single-strand (ss) DNA substrate flexibility determined by the mesoscale sequence surrounding AID deaminase motifs. Mesoscale DNA sequences containing flexible pyrimidine-pyrimidine bases bind effectively to the positively charged surface patches of AID, resulting in preferential deamination activities. The CDR hypermutability is mimicable in in vitro deaminase assays and is evolutionarily conserved among species using SHM as a major diversification strategy. We demonstrated that mesoscale sequence alterations tune the in vivo mutability and promote mutations in an otherwise cold region in mice. Our results show a non-coding role of antibody-coding sequence in directing hypermutation, paving the way for the synthetic design of humanized animal models for optimal antibody discovery and explaining the AID mutagenesis pattern in lymphoma.

MSGCL: inferring miRNA-disease associations based on multi-view self-supervised graph structure contrastive learning.

Potential miRNA-disease associations (MDA) play an important role in the discovery of complex human disease etiology. Therefore, MDA prediction is an attractive research topic in the field of biomedical machine learning. Recently, several models have been proposed for this task, but their performance limited by over-reliance on relevant network information with noisy graph structure connections. However, the application of self-supervised graph structure learning to MDA tasks remains unexplored. Our study is the first to use multi-view self-supervised contrastive learning (MSGCL) for MDA prediction. Specifically, we generated a learner view without association labels of miRNAs and diseases as input, and utilized the known association network to generate an anchor view that provides guiding signals for the learner view. The graph structure was optimized by designing a contrastive loss to maximize the consistency between the anchor and learner views. Our model is similar to a pre-trained model that continuously optimizes upstream tasks for high-quality association graph topology, thereby enhancing the latent representation of association predictions. The experimental results show that our proposed method outperforms state-of-the-art methods by 2.79$\%$ and 3.20$\%$ in area under the receiver operating characteristic curve (AUC) and area under the precision/recall curve (AUPR), respectively.

Bile exosomal miR-182/183-5p increases cholangiocarcinoma stemness and progression by targeting HPGD and increasing PGE2 generation.

BACKGROUND AIMS: Cholangiocarcinoma (CCA) is a highly lethal malignancy originating from the biliary ducts. Current CCA diagnostic and prognostic assessments cannot satisfy the clinical requirement. Bile detection is rarely performed, and herein, we aim to estimate the clinical significance of bile liquid biopsy by assessing bile exosomal concentrations and components. APPROACH RESULTS: Exosomes in bile and sera from CCA, pancreatic cancer, and common bile duct stone were identified and quantified by transmission electronmicroscopy, nanoparticle tracking analysis, and nanoFCM. Exosomal components were assessed by liquid chromatography with tandem mass spectrometry and microRNA sequencing (miRNA-seq). Bile exosomal concentration in different diseases had no significant difference, but miR-182-5p and miR-183-5p were ectopically upregulated in CCA bile exosomes. High miR-182/183-5p in both CCA tissues and bile indicates a poor prognosis. Bile exosomal miR-182/183-5p is secreted by CCA cells and can be absorbed by biliary epithelium or CCA cells. With xenografts in humanized mice, we showed that bile exosomal miR-182/183-5p promotes CCA proliferation, invasion, and epithelial-mesenchymal transition (EMT) by targeting hydroxyprostaglandin dehydrogenase in CCA cells and mast cells (MCs), and increasing prostaglandin E2 generation, which stimulates PTGER1 and increases CCA stemness. In single-cell mRNA-seq, hydroxyprostaglandin dehydrogenase is predominantly expressed in MCs. miR-182/183-5p prompts MC to release VEGF-A release from MC by increasing VEGF-A expression, which facilitates angiogenesis. CONCLUSIONS: CCA cells secret exosomal miR-182/183-5p into bile, which targets hydroxyprostaglandin dehydrogenase in CCA cells and MCs and increases prostaglandin E2 and VEGF-A release. Prostaglandin E2 promotes stemness by activating PTGER1. Our results reveal a type of CCA self-driven progression dependent on bile exosomal miR-182/183-5p and MCs, which is a new interplay pattern of CCA and bile.

PTPN9 dephosphorylates FGFR2 pY656/657 through interaction with ACAP1 and ameliorates pemigatinib effect in cholangiocarcinoma.

ABSTRACT AND AIM: Cholangiocarcinoma (CCA) is a highly aggressive and lethal cancer that originates from the biliary epithelium. Systemic treatment options for CCA are currently limited, and the first targeted drug of CCA, pemigatinib, emerged in 2020 for CCA treatment by inhibiting FGFR2 phosphorylation. However, the regulatory mechanism of FGFR2 phosphorylation is not fully elucidated. APPROACH AND RESULTS: Here we screened the FGFR2-interacting proteins and showed that protein tyrosine phosphatase (PTP) N9 interacts with FGFR2 and negatively regulates FGFR2 pY656/657 . Using phosphatase activity assays and modeling the FGFR2-PTPN9 complex structure, we identified FGFR2 pY656/657 as a substrate of PTPN9, and found that sec. 14p domain of PTPN9 interacts with FGFR2 through ACAP1 mediation. Coexpression of PTPN9 and ACAP1 indicates a favorable prognosis for CCA. In addition, we identified key amino acids and motifs involved in the sec. 14p-APCP1-FGFR2 interaction, including the "YRETRRKE" motif of sec. 14p, Y471 of PTPN9, as well as the PH and Arf-GAP domain of ACAP1. Moreover, we discovered that the FGFR2 I654V substitution can decrease PTPN9-FGFR2 interaction and thereby reduce the effectiveness of pemigatinib treatment. Using a series of in vitro and in vivo experiments including patient-derived xenografts (PDX), we showed that PTPN9 synergistically enhances pemigatinib effectiveness and suppresses CCA proliferation, migration, and invasion by inhibiting FGFR2 pY656/657 . CONCLUSIONS: Our study identifies PTPN9 as a negative regulator of FGFR2 phosphorylation and a synergistic factor for pemigatinib treatment. The molecular mechanism, oncogenic function, and clinical significance of the PTPN9-ACAP1-FGFR2 complex are revealed, providing more evidence for CCA precision treatment.

Enhanced Recognition of a Herbal Compound Epiberberine by a DNA Quadruplex-Duplex Structure.

The small molecule epiberberine (EPI) is a natural alkaloid with versatile bioactivities against several diseases including cancer and bacterial infection. EPI can induce the formation of a unique binding pocket at the 5' side of a human telomeric G-quadruplex (HTG) sequence with four telomeric repeats (Q4), resulting in a nanomolar binding affinity (KD approximately 26 nM) with significant fluorescence enhancement upon binding. It is important to understand (1) how EPI binding affects HTG structural stability and (2) how enhanced EPI binding may be achieved through the engineering of the DNA binding pocket. In this work, the EPI-binding-induced HTG structure stabilization effect was probed by a peptide nucleic acid (PNA) invasion assay in combination with a series of biophysical techniques. We show that the PNA invasion-based method may be useful for the characterization of compounds binding to DNA (and RNA) structures under physiological conditions without the need to vary the solution temperature or buffer components, which are typically needed for structural stability characterization. Importantly, the combination of theoretical modeling and experimental quantification allows us to successfully engineer Q4 derivative Q4-ds-A by a simple extension of a duplex structure to Q4 at the 5' end. Q4-ds-A is an excellent EPI binder with a KD of 8 nM, with the binding enhancement achieved through the preformation of a binding pocket and a reduced dissociation rate. The tight binding of Q4 and Q4-ds-A with EPI allows us to develop a novel magnetic bead-based affinity purification system to effectively extract EPI from Rhizoma coptidis (Huang Lian) extracts.

Linear-Array Endoscopic Ultrasound and Narrow-Band Imaging Measure the Invasion Depth of Nonpedunculated Rectal Lesions With Comparable Accuracy Based on a Randomized Controlled Trial.

INTRODUCTION: Linear-array endoscopic ultrasound (EUS) and narrow-band imaging (NBI) are both used to estimate the invasion depth of nonpedunculated rectal lesions (NPRLs). However, it is unclear which procedure is more accurate. This randomized controlled trial aimed to compare the diagnostic accuracy of linear EUS and NBI for estimating the invasion depth of NPRLs. METHODS: This study is a single-center, randomized, tandem trial. Eligible patients with NPRLs were randomly assigned to A group (assessment with EUS followed by NBI) or B group (assessment with NBI followed by EUS). The invasion depth of each lesion was independently measured by each procedure and categorized as mucosal to slight submucosal (M-SM s , invasion depth <1,000 µm) or deep submucosal (SM d , invasion depth ≥1,000 µm) invasion, with postoperative pathology as the standard of measurement. The primary outcome was diagnostic accuracy, and secondary outcomes included sensitivity, specificity, and procedure time. RESULTS: Eighty-six patients with NPRLs were enrolled, and 79 patients were finally analyzed, including 39 cases in the A group and 40 cases in the B group. Comparable diagnostic accuracies were observed between EUS and NBI (96.2% vs 93.7%, P = 0.625). EUS identified lesions with deep submucosal invasion with 81.8% sensitivity while that of NBI was 63.6% ( P = 0.500). The specificity of both EUS and NBI was 98.5%. The procedure time was also similar between EUS and NBI (5.90 ± 3.44 vs 6.4 ± 3.94 minutes, P = 0.450). Furthermore, the combined use of EUS and NBI did not improve diagnostic accuracy compared with EUS or NBI alone (94.9% vs 96.2% vs 93.7%, P = 0.333). DISCUSSION: Linear EUS and NBI measure the invasion depth of NPRLs with comparable accuracy. The combination of the 2 methods does not improve the diagnostic accuracy. Single NBI should be preferred, considering its simplicity and convenience in clinical practice.

Polystyrene-Based Matrix to Enhance the Fluorescence of Aggregation-Induced Emission Luminogen for Fluorescence-Guided Surgery.

Achieving ultrabright fluorogens is a key issue for fluorescence-guided surgery (FGS). Fluorogens with aggregation-induced emission (AIEgens) are potential agents for FGS on the benefit of the bright fluorescence in physiological conditions. Herein, the fluorescence brightness of AIEgen is further improved by preparing the nanoparticle using a polystyrene-based matrix and utilizing it for tumor FGS with a high signal-to-background ratio. After encapsulating AIEgen into polystyrene-poly (ethylene glycol) (PS-PEG), the fluorescence intensity of the prepared AIE@PS-PEG nanoparticles is multiple times that of nanoparticles in 1, 2-distearoyl-sn-glycero-3-phosphoethanolamine-poly (ethylene glycol) (DSPE-PEG), a commonly used polymer matrix for nanoparticle preparation. Molecular dynamics simulations suggest that higher free energy is required for the outer rings of AIEgen to rotate in polystyrene than in the DSPE, indicating that the benzene rings in polystyrene can restrict the intramolecular motions of AIEgen better than the alkyl chain in DSPE-PEG. Fluorescence correlation microscopy detections suggest that the triplet excited state of AIEgens is less in PS-PEG than in DSPE-PEG. The restricted intramolecular motions and suppressed triplet excited state result in ultrabright AIE@PS-PEG nanoparticles, which are more conducive to illuminating tumor tissues in the intestine for FGS. The illumination of metastatic tumors in lungs by AIE@PS-PEG nanoparticles is also tried.

Structures of the ADGRG2-Gs complex in apo and ligand-bound forms.

Adhesion G protein-coupled receptors are elusive in terms of their structural information and ligands. Here, we solved the cryogenic-electron microscopy (cryo-EM) structure of apo-ADGRG2, an essential membrane receptor for maintaining male fertility, in complex with a Gs trimer. Whereas the formations of two kinks were determinants of the active state, identification of a potential ligand-binding pocket in ADGRG2 facilitated the screening and identification of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate and deoxycorticosterone as potential ligands of ADGRG2. The cryo-EM structures of DHEA-ADGRG2-Gs provided interaction details for DHEA within the seven transmembrane domains of ADGRG2. Collectively, our data provide a structural basis for the activation and signaling of ADGRG2, as well as characterization of steroid hormones as ADGRG2 ligands, which might be used as useful tools for further functional studies of the orphan ADGRG2.

Striatonigrostriatal connectivity-based cross-species parcellation of human and macaque substantia nigra.

Anatomical and functional heterogeneous substantia nigra (SN) has been extensively studied in humans and animals like rhesus monkeys given its crucial role in modulating a broad range of behaviors. Increasingly important cross-species research of SN may require connectionally homogeneous and homologous subregions of SN as objective and stable starting points from which the evolutionary characteristics of brain could be inspected. However, existing atlases of SN were all inaccurate mappings as a cross-species connectome atlas due to inadequate homology constraint during their constructions, and arbitrary paired use of these atlases might cause unreliable findings. In this study, a reliable blind-source cross-species parcellation of SN was developed based on the following rationale: striatonigrostriatal circuits form major structure of nigral connectivity; different nigral components have unique striatonigrostriatal connectivity; and inter-species corresponding human and macaque nigral components have similar striatonigrostriatal connectivity. Specifically, all voxels in human and macaque SN were grouped together and then classified based on inter-species identically characterized striatonigrostriatal connectivity attributes. Our results delineated a pars compacta-pars reticulate-like parcellation and further demonstrated its reliability by illustrating best-matched whole-brain structural and functional connectivity profiles of inter-species corresponding nigral subregions. Detailed inter-species and inter-regional differences in multi-aspect connectivities of these nigral subregions were inspected. It is expected that this cross-species connectome atlas of SN can offer biologically reliable cornerstones and important information to facilitate future cross-species research.

Baicalin inhibits hepatocellular carcinoma cell growth and metastasis by suppressing ROCK1 signaling.

Hepatocellular carcinoma (HCC) is a common malignancy affecting many people worldwide. Baicalin is a flavonoid extracted from the dried root of Scutellaria baicalensis Georgi. It can effectively inhibit the occurrence and development of HCC. Nonetheless, the mechanism through which Baicalin inhibits HCC growth and metastasis remain unknown. This work discovered that Baicalin inhibited HCC cell proliferation, invasion, metastasis while inducing cell cycle arrest at the G0/G1 phase and apoptosis. In vivo HCC xenograft results indicated that Baicalin inhibited HCC growth. Western blotting analysis indicated that Baicalin suppressed the expressions of ROCK1, p-GSK-3ß, and ß-catenin, whereas it up-regulated the expressions of GSK-3ß and p-ß-catenin. Baicalin also reduced the expressions of Bcl-2, C-myc, Cyclin D1, MMP-9, and VEGFA, while increasing the expression of Bax. Molecular docking revealed that Baicalin docked in the binding site of the ROCK1 agonist, with a binding energy of -9 kcal/mol between the two. In addition, lentivirus-mediated suppression of ROCK1 expression improved the inhibitory effect of Baicalin on the proliferation, invasion, and metastasis of HCC and the expression of proteins associated with ROCK1/GSK-3ß/ß-catenin signaling pathway. Moreover, restoring ROCK1 expression decreased the anti-HCC efficacy of Baicalin. These findings suggest that Baicalin may decrease HCC proliferation and metastasis by suppressing ROCK1/GSK-3ß/ß-catenin signaling.

The role of HPV status in patients with overlapping grey zone cancer in oral cavity and oropharynx.

PURPOSE: We aimed to explore the clinicodemographic characteristics and prognosis of grey zone squamous cell cancer (GZSCC) located in the overlapping or ambiguous area of oral cavity and oropharynx and to identify valuable factors that would improve its differential diagnosis and prognosis. METHODS: Information of GZSCC patients in the Surveillance, Epidemiology, and End Results (SEER) database were compared to patients with oral cavity (OCSCC) and oropharyngeal (OPSCC) squamous cell carcinomas with corresponding HPV status, respectively. Kaplan-Meier method with log-rank test and multivariate Cox regression analysis were applied to assess associations between clinical characteristics and overall survival (OS). A predictive model integrating age, gender, marital status, HPV status and staging variables was conducted to classify GZSCC patients into three risk groups and verified internally by tenfold cross validation. RESULTS: A total of 3318 GZSCC, 10792 OPSCC and 6656 OCSCC patients were identified. HPV-positive GZSCC patients had the best 5-year OS as HPV-positive OPSCC (81% vs. 82%). However, the 5-year OS of HPV-negative/unknown GZSCC (43%/42%) were the worst among all groups, indicating that HPV status and the overlapping nature of tumors were valuable prognostic predictors in GZSCC patients. Compared with the strategy of dividing GZSCC into two groups by HPV status, the predictive model integrating more variables could additionally identify a unique high-risk GZSCC group with the lowest OS rate. CONCLUSIONS: GZSCC patients had distinct clinical characteristics and prognosis compared with OPSCC and OCSCC, integrating HPV status and other clinical factors could help distinguish GZSCC and predict their prognosis.

Evaluation of a novel disposable esophagogastroduodenoscopy system in emergency, bedside, and intraoperative settings: Pilot study (with videos).

OBJECTIVES: The disposable esophagogastroduodenoscopy (EGD) system is a novel endoscopic device which is highly portable and is designed to eliminate the risk of cross-infection caused by reusable EGD. This study aimed to investigate the feasibility and safety of disposable EGD in emergency, bedside, and intraoperative settings. METHODS: This was a prospective, single-center, noncomparative study. Disposable EGD was used for emergency, bedside, and intraoperative endoscopies in 30 patients. The primary end-point was the technical success rate of the disposable EGD. Secondary end-points included technical performance indicators including clinical operability, image quality score, procedure time, the incidence of device malfunction and/or failure, and the incidence of adverse events. RESULTS: A total of 30 patients underwent diagnosis and/or treatment with disposable EGD. Therapeutic EGD was performed on 13/30 patients, including hemostasis (n = 3), foreign body retrieval (n = 6), nasoenteric tube placement (n = 3), and percutaneous endoscopic gastrostomy (n = 1). The technical success rate was 100%: all procedures and indicated interventions were completed without changing to a conventional upper endoscope. The mean image quality score obtained immediately after procedure completion was 3.72 ± 0.56. The mean (± SD) procedure time was 7.4 (± 7.6) min. There were no device malfunctions or failures, device-related adverse events, or overall adverse events. CONCLUSION: The disposable EGD may be a feasible alternative to the traditional EGD in emergency, bedside, and intraoperative settings. Preliminary data show that it is a safe and effective tool for diagnosis and treatment in emergency and bedside upper gastrointestinal cases. TRIAL REGISTRATION: Chinese Clinical Trial Registry (Trial ID: ChiCTR2100051452, https://www.chictr.org.cn/showprojen.aspx?proj=134284).

Supra-Cyanines: Ultrabright Cyanine-Based Fluorescent Supramolecular Materials in Solution and in the Solid State.

Fluorescent materials with high brightness play a crucial role in the advancement of various technologies such as bioimaging, photonics, and OLEDs. While significant efforts are dedicated to designing new organic dyes with improved performance, enhancing the brightness of existing dyes holds equal importance. In this study, we present a simple supramolecular strategy to develop ultrabright cyanine-based fluorescent materials by addressing long-standing challenges associated with cyanine dyes, including undesired cis-trans photoisomerization and aggregation-caused quenching. Supra-cyanines are obtained by incorporating cyanine moieties in a cyclic peptide-based supramolecular scaffold, and exhibit high fluorescence quantum yields (up to 50 %) in both solution and in the solid state. These findings offer a versatile approach for constructing highly emissive cyanine-based supramolecular materials.

Modified Cap-Assisted Endoscopic Mucosal Resection Versus Endoscopic Submucosal Dissection for the Treatment of Rectal Neuroendocrine Tumors ≤10 mm: A Randomized Noninferiority Trial.

INTRODUCTION: Although recent guidelines recommend endoscopic resection of rectal neuroendocrine tumors (NET) ≤10 mm, there is no consensus on which endoscopic modality should be performed. We aimed to compare the safety and efficacy of modified cap-assisted endoscopic mucosal resection (mEMR-C) and endoscopic submucosal dissection (ESD) methods for the treatment of rectal NET ≤10 mm. METHODS: A randomized noninferiority trial comparing mEMR-C and ESD was conducted. The primary outcome was the histological complete resection rate; the secondary outcomes included en bloc resection rate, operation time, complications, and so on. Subgroup analyses and follow-up were also performed. RESULTS: Ninety patients were enrolled, and 79 patients with pathologically confirmed rectal NET were finally analyzed, including 38 cases of mEMR-C and 41 cases of ESD. Histological complete resection rate was 97.4% in the mEMR-C group and 92.7% in the ESD group. The noninferiority of mEMR-C compared with that of ESD was confirmed because the absolute difference was 4.7% (2-sided 90% confidence interval, -3.3% to 12.2%; P = 0.616). En bloc resection and successful removal of rectal NET were achieved in all patients. Advantages of mEMR-C over ESD included shorter operation time (8.89 ± 4.58 vs 24.8 ± 9.14 minutes, P < 0.05) and lower hospitalization cost ($2,233.76 ± $717.70 vs $2,987.27 ± $871.81, P < 0.05). Postoperative complications were recorded in 4 patients who received mEMR-C and 2 patients in the ESD group (11.5% vs 4.9%, P = 0.509), which were all well managed using endoscopy. Similar findings were observed when subgroup analysis was performed. DISCUSSION: mEMR-C is noninferior to ESD with a similar complete resection rate. In addition, mEMR-C had shorter procedure duration time and lower hospitalization costs. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03982264.

Occult lymph node metastasis in the contralateral neck of oropharyngeal squamous cell carcinoma: a meta-analysis and literature review.

PURPOSE: The purpose of this study was to determine whether contralateral cervical lymph node dissection is needed in patients with oropharyngeal squamous cell carcinoma (OPSCC) with contralateral cervical cN0. METHODS: We searched the PubMed, Web of Science, Embase, Chinese Biomedical Literature Database (CBM) and Cochrane Library databases up to August 14, 2021 for studies examining the contralateral neck occult metastasis rate of patients with ipsilateral clinical neck-negative (cN0) OPSCC and the contralateral neck occult metastasis rate of patients with ipsilateral clinical neck-positive (cN1, cN2a, cN2b) OPSCC. This rate is used to determine whether patients with contralateral cN0 OPSCC need contralateral cervical lymph node dissection. RESULTS: A total of 14 articles, including 532 cases, were included in the analysis. When studying the rate of ipsilateral cervical occult metastasis in patients with ipsilateral cN0, 163 cases were included in 11 studies. The results showed that the rate of contralateral cervical occult lymph node metastasis in patients with ipsilateral cN0 was 0.6816% (95% CI 0.0000-4.4880 (P = 0.3005)). In the study of ipsilateral cN+ (cN1, cN2a, cN2b), a total of 369 cases of 10 articles were included in the analysis. The results showed that the rate of contralateral cervical occult lymph node metastasis in patients with ipsilateral cN+ was 11.4920% [95% CI 7.8944-15.5223 (P = 0.0000)]. CONCLUSION: For cancer treatment, the ultimate goal is to achieve the best control of cancer and the lowest complications. It seems unnecessary to intervene in the contralateral neck of patients with OPSCC with ipsilateral cN0. For OPSCC with ipsilateral cN+ , this index is a factor that cannot be ignored when making clinical decisions.

Two-Stage Segmentation Framework Based on Distance Transformation.

With the rise of deep learning, using deep learning to segment lesions and assist in diagnosis has become an effective means to promote clinical medical analysis. However, the partial volume effect of organ tissues leads to unclear and blurred edges of ROI in medical images, making it challenging to achieve high-accuracy segmentation of lesions or organs. In this paper, we assume that the distance map obtained by performing distance transformation on the ROI edge can be used as a weight map to make the network pay more attention to the learning of the ROI edge region. To this end, we design a novel framework to flexibly embed the distance map into the two-stage network to improve left atrium MRI segmentation performance. Furthermore, a series of distance map generation methods are proposed and studied to reasonably explore how to express the weight of assisting network learning. We conduct thorough experiments to verify the effectiveness of the proposed segmentation framework, and experimental results demonstrate that our hypothesis is feasible.

Cutting environmental footprints of maize systems in China through Nutrient Expert management.

Excessive fertilizer consumption, poor management, and intense pollution currently restrict sustainable agriculture in China. To address these problems, two 9-year experiments involving typical maize production systems in Northcentral China (summer maize) and Northeast China (spring maize) were conducted to evaluate the effectiveness of Nutrient Expert (NE) management, a Nutrient Decision Support System which combines 4 R nutrient management with improved varieties and optimized plant density, on reducing carbon (C) and nitrogen (N) footprints. The mean grain yields under NE were 7.4 and 11.5 tons ha-1, which were 3.9% and 6.9% higher than those of local farmers' practices (FP) in the summer and spring maize systems, respectively; the N-derived (affected by N fertilization) yield accounted for 21.7% and 73.5% of the total yield under NE, respectively. Compared with FP, NE achieved 21.8% and 16.0% lower reactive nitrogen (Nr) losses, 18.4% and 20.9% lower greenhouse gas (GHG) emissions, 24.8% and 21.4% smaller N footprints (9.1 and 2.3 kg N ton-1 grain), and 21.5% and 26.0% smaller C footprints (436 and 206 kg CO2 eq ton-1 grain) in summer and spring maize, respectively. NE reduced the N-derived N and C footprints by 30.3% and 27.2% in summer maize and 22.9% and 28.0% in spring maize, respectively, as a result of greater yields and optimal N management. Moreover, compared with summer maize, spring maize showed significantly smaller N-derived N (12.6-fold) and C (7.2-fold) footprints. The results demonstrated the ability of long-term NE management to sustain maize yields, reduce Nr losses and GHG emissions, and cut C and N footprints, indicating its potential suitability as an alternative management for sustainable agriculture. Moreover, the summer maize system still had considerable potential for environmental footprints reduction even when current NE management practices were adopted.

Peptide-Drug Conjugate-Based Nanocombination Actualizes Breast Cancer Treatment by Maytansinoid and Photothermia with the Assistance of Fluorescent and Photoacoustic Images.

To develop a highly efficient strategy against tumors, here, a nanocombination (PDC/P@HCuS) was designed and constructed to actualize chemo-phototherapy with the assistance of fluorescence (FL) and photoacoustic (PA) images. First, a type of organic-inorganic hybrid nanosystem (P@HCuS) was engineered by coupling the fluorescence-labeled amphiphilic fPEDC copolymer on the surface of hollow mesoporous copper sulfide nanoparticle (HCuS), in which HCuS was used as a photothermal and PA agent; fPEDC as a stabilizer, chromophore, and redox/pH-sensitive gatekeeper; and both of them as drug carriers. Then, a peptide-drug conjugate (cRGD-SMCC-DM1, PDC), as a molecular targeted maytansinoid, was loaded inside of P@HCuS to form PDC/P@HCuS. Next, the PDC/P@HCuS was investigated carefully with or without near-infrared (NIR) laser irradiation. In vitro, the nanocombination exhibited stimuli-responsive drug release, obvious cellular uptake, strong cytotoxicity to tumor cells, significant impact on cell cycle, and cytoskeleton and cellular proteomics as well as evident permeability into the tumor sphere, most of which could be boosted by NIR laser irradiation. In vivo, the nanocombinaiton exerted good FL/PA imaging features and photothermal efficiency, achieved the best antitumor efficacy in the presence of NIR laser irradiation, and showed excellent biosafety. Together, it demonstrated that the PDC/P@HCuS, representing a chemo-phototherapy based on a nanocombination associated with peptide-drug conjugate, could achieve the highly efficient antitumor effect.

Estimation of nitrogen supply for winter wheat production through a long-term field trial in China.

Excessive synthetic nitrogen (N) applications, high mineral N accumulation and low N use efficiency (NUE) are current issues in intensively cultivated winter wheat production system impeding the sustainable development of agriculture in China. To solve these problems, soil accumulated N in the top 1 m of the soil profile before sowing (Nsoil), returned straw-N from the previous maize crop (Nstraw) and fertilizer N application (Nfertilizer) should be comprehensively considered N supply sources in N management. As such, the objective of this research was to determine the optimal total N supply (TNsupply) level needed to meet crop requirements while minimizing environmental impacts. A 9-year on-farm experiment was conducted in accordance with a split-plot design involving two different fertilizer management systems (main treatments) and three N application strategies (sub treatments). Extensive TNsupply levels (ranging from 61 kg ha-1 to 813 kg ha-1) were detected, and relative yield (RY), N input and N output in response to the TNsupply were measured. The relationships between TNsupply and RY, N input, and N output strongly fit linear-plateau, linear, and linear-plateau models, respectively. The minimum TNsupply levels needed to achieve the maximum RY and N output were 325 and 392 kg ha-1, respectively. On the basis of N supply capacity, the TNsupply was removed from the growing system by 61% (N input). As the N input increased past 209 kg ha-1, the NUE declined, at which point the TNsupply reached 433 kg ha-1. Therefore, the suitable TNsupply should range from 325 kg ha-1 (ensuring a total N supply for high yield and N uptake) to 433 kg ha-1 (obtaining a relatively higher NUE and less N loss to the environment). The TNsupply was highlighted to be an indicator for use in N management recommendations. Considering the average high N accumulation in winter wheat production systems, N management should essentially take into account the consumption of Nsoil, the levels of Nstraw and the minimum application of Nfertilizer to obtain high yields while minimizing environmental impacts under suitable TNsupply levels.

Biochemical characterization of G64W mutant of acidic beta-crystallin 4.

Crystallins are structural proteins in the lens that last a lifetime with little turnover. Deviant in crystallins can cause rare but severe visual impairment, namely, congenital cataracts. It is reported that several mutations in the acidic ß-crystallin 4 (CRYBA4) are related to congenital cataracts. However, the pathogenesis of these mutants is not well understood at molecular level. Here we evaluate the biochemical properties of wild type CRYBA4 (CRYBA4WT) and a pathogenic G64W mutant (CRYBA4G64W) including protein folding, polymerization state and protein stability. Furthermore, we explore the differences in their interactions with α-crystallin A (CRYAA) and basic ß-crystallin 1 (CRYBB1) via yeast two-hybrid and pull-down assay in vitro, through which we find that G64W mutation leads to protein misfolding, decreases protein stability, blocks its interaction with CRYBB1 but maintains its interaction with CRYAA. Our results deepen our understanding of the pathogenesis of congenital cataracts.