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Wang R, Zhang Y, Liang J, Li Y, Wang J. Heterotopic pregnancy: a case report of intrauterine hydatidiform mole with tubal pregnancy. J Int Med Res 2024; 52:3000605241258572. [PMID: 38869107 PMCID: PMC11179464 DOI: 10.1177/03000605241258572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 05/15/2024] [Indexed: 06/14/2024] Open
Abstract
We herein report a rare case of simultaneous intrauterine molar pregnancy and tubal pregnancy. A woman of childbearing age who had never been pregnant underwent an ultrasound examination 70 days after the onset of menopause. She had a history of ovulation induction. The ultrasound findings suggested a partial hydatidiform mole. She was then pathologically confirmed to have a complete hydatidiform mole after uterine suction dilation and curettage. On postoperative day 4, an ultrasound examination before discharge showed an inhomogeneous mass in the left adnexal region with mild lower abdominal pain. On postoperative day 17, the blood human chorionic gonadotropin level did not drop as expected, and a follow-up examination still indicated a mass in the left adnexal region. We were unable to rule out an ectopic hydatidiform mole. Hysteroscopy with laparoscopic exploration of the left adnexal mass and salpingotomy suggested a diagnosis of intrauterine hydatidiform mole combined with left tubal pregnancy.
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Cai W, Peng S, Tian Y, Bao Y, Liu Q, Dong Y, Liang Z, Liu Q, Ren Y, Ding P, Liu J, Xu T, Li Y. Hydrophobic core evolution of major histocompatibility complex class I chain-related protein A for dramatic enhancing binding affinity. Int J Biol Macromol 2024; 271:132588. [PMID: 38788878 DOI: 10.1016/j.ijbiomac.2024.132588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 05/19/2024] [Accepted: 05/21/2024] [Indexed: 05/26/2024]
Abstract
Interface residues at sites of protein-protein interaction (PPI) are the focus for affinity optimisation. However, protein hydrophobic cores (HCs) play critical roles and shape the protein surface. We hypothesise that manipulating protein HCs can enhance PPI interaction affinities. A cell stress molecule, major histocompatibility complex class I chain-related protein A (MICA), binds to the natural killer group 2D (NKG2D) homodimer to form three molecule interactions. MICA was used as a study subject to support our hypothesis. We redesigned MICA HCs by directed mutagenesis and isolated high-affinity variants through a newly designed partial-denature panning (PDP) method. A few mutations in MICA HCs increased the NKG2D-MICA interaction affinity by 325-5613-fold. Crystal structures of the NKG2D-MICA variant complexes indicated that mutagenesis of MICA HCs stabilised helical elements for decreasing intermolecular interactive free energy (ΔG) of the NKG2D-MICA heterotrimer. The repacking of MICA HC mutants maintained overall surface residues and the authentic binding specificity of MICA. In conclusion, this study provides a new method for MICA redesign and affinity optimisation through HC manipulation without mutating PPI interface residues. Our study introduces a novel approach to protein manipulation, potentially expanding the toolkit for protein affinity optimisation.
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Nguyen NT, Nguyen BPT, Ho TN, Tran CND, Tran THH, Nguyen HPH, Nguyen HP, Huynh NT, Li Y, Phan VHG, Thambi T. Orally ingestible medication utilizing layered double hydroxide nanoparticles strengthened alginate and hyaluronic acid-based hydrogel bead for bowel disease management. Int J Biol Macromol 2024; 269:132122. [PMID: 38718992 DOI: 10.1016/j.ijbiomac.2024.132122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 04/30/2024] [Accepted: 05/04/2024] [Indexed: 05/30/2024]
Abstract
In the treatment of bowel diseases such as ulcerative colitis through oral administration, an effective drug delivery system targeting the colon is crucial for enhancing efficacy and minimizing side effects of therapeutic agents. This study focuses on the development of a novel nanocomposite hydrogel bead comprising a synergistic blend of biological macromolecules, namely sodium alginate (ALG) and hyaluronic acid (HA), reinforced with layered double hydroxide nanoparticles (LDHs) for the oral delivery of dual therapeutics. The synthesized hydrogel bead exhibits significantly enhanced gel strength and controllable release of methylprednisolone (MP) and curcumin (CUR), serving as an anti-inflammatory drug and a mucosal healing agent, compared to native ALG or ALG/HA hydrogel beads without LDHs. The physicochemical properties of the synthesized LDHs and hydrogel beads were characterized using various techniques, including scanning electron microscopy, zeta potential measurement, transmission electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. In vitro release studies of MP and CUR under simulated gastrointestinal tract (GIT) conditions demonstrate the superior controlled release property of the nanocomposite hydrogel bead, particularly in minimizing premature drug release in the upper GIT environment while sustaining release of over 82 % of drugs in the colonic environment. Thus, the modularly engineered carrier designed for oral colon targeting holds promise as a potential candidate for the treatment of ulcerative colitis.
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Li Y, Wong M, Zhan L, Corke L, Brown MC, Cheng S, Khan K, Balatnaram K, Chowdhury M, Sabouhanian A, Herman J, Walia P, Strom E, Patel D, García-Pardo M, Schmid S, Eng L, Sacher AG, Leighl N, Bradbury PA, Shepherd FA, Shultz D, Liu G. Single organ metastatic sites in non-small cell lung cancer: Patient characteristics, treatment patterns and outcomes from a large retrospective Canadian cohort. Lung Cancer 2024; 192:107823. [PMID: 38763103 DOI: 10.1016/j.lungcan.2024.107823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 04/17/2024] [Accepted: 05/12/2024] [Indexed: 05/21/2024]
Abstract
BACKGROUND There is a paucity of information about the characteristics, treatment patterns, and outcomes of non-small cell lung cancer (NSCLC) patients with single organ metastasis (SOM). METHODS This retrospective cohort study includes all patients with a diagnosis of stage IV NSCLC diagnosed from 2014 to 2016 and treated at Princess Margaret Cancer Centre. We compared baseline characteristics and patterns of metastatic sites between patients with SOM versus multiple (M)OM. Additionally, we identified treatment modalities and outcomes for patients with SOM. Cox multivariable models (MVA) were utilized to evaluate differences in overall survival (OS) between the SOM and MOM cohorts. RESULTS Of 893 pts analyzed, 457 (51 %) had SOM, while 436 (49 %) had MOM at initial diagnosis. Demographics were comparable between the two groups. Brain was the most common site of metastasis for SOM patients. When compared to the MOM group, the SOM group had lower percentages of liver and adrenal metastases. Amongst SOM patients, 54 % received single modality treatment, and 20 % did not receive any treatment for their SOM. In MVA, patients with liver (HR 2.4), bone (HR 1.8), and pleural (HR 1.7) metastasis as their SOM site had the worst outcomes, with median OS of 6.8 months, 12.1 months, and 13.0 months respectively. Patients with SOM had a significantly improved median OS compared to those with MOM (15.9 months vs. 10.6 months; HR 0.56, 95 % CI 0.47-0.66, p < 0.001). CONCLUSION In NSCLC patients who presented with SOM, survival correlated with the initial organ involved and was better overall compared to patients with MOM. SOM NSCLC may benefit from specific management strategies and SOM patients could be considered as a specific subgroup for survival analyses in observational and non-randomized interventional studies. In clinical trials, SOM can be considered as a stratification factor in the future.
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Chang Y, Chen M, Yu C, Li Y, Chen L, Yan L. Direction and Residual Awareness Curriculum Learning Network for Rain Streaks Removal. IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 2024; 35:8414-8428. [PMID: 37018699 DOI: 10.1109/tnnls.2022.3227730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Single-image rain streaks' removal has attracted great attention in recent years. However, due to the highly visual similarity between the rain streaks and the line pattern image edges, the over-smoothing of image edges or residual rain streaks' phenomenon may unexpectedly occur in the deraining results. To overcome this problem, we propose a direction and residual awareness network within the curriculum learning paradigm for the rain streaks' removal. Specifically, we present a statistical analysis of the rain streaks on large-scale real rainy images and figure out that rain streaks in local patches possess principal directionality. This motivates us to design a direction-aware network for rain streaks' modeling, in which the principal directionality property endows us with the discriminative representation ability of better differing rain streaks from image edges. On the other hand, for image modeling, we are motivated by the iterative regularization in classical image processing and unfold it into a novel residual-aware block (RAB) to explicitly model the relationship between the image and the residual. The RAB adaptively learns balance parameters to selectively emphasize informative image features and better suppress the rain streaks. Finally, we formulate the rain streaks' removal problem into the curriculum learning paradigm which progressively learns the directionality of the rain streaks, rain streaks' appearance, and the image layer in a coarse-to-fine, easy-to-hard guidance manner. Solid experiments on extensive simulated and real benchmarks demonstrate the visual and quantitative improvement of the proposed method over the state-of-the-art methods.
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Xiong T, Li X, Ma Z, Liu K, Li Y, Li C, Luo F, Yang Z. Modulation in work function of CoTe as bifunctional electrocatalyst for rechargeable zinc air battery. J Colloid Interface Sci 2024; 672:170-178. [PMID: 38838626 DOI: 10.1016/j.jcis.2024.05.232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/29/2024] [Accepted: 05/31/2024] [Indexed: 06/07/2024]
Abstract
The sluggish kinetics and inferior stability of oxygen electrocatalyst in rechargeable zinc air battery (ZAB) hamper its industrialization. In this work, we activate cobalt telluride (CoTe) by introduction of metallic cobalt (Co) to modulate the work function to facilitate the electron transfer from Co to CoTe during oxygen catalysis; additionally, the three-dimensional porous carbon nanosheets (3DPC) are invited to reduce the resistance towards electrolyte/oxygen diffusion. Thereby, Co-CoTe@3DPC only demands 280 mV overpotential to reach 10 mA cm-2 under alkaline oxygen evolution reaction (OER) condition, relatively lower than commercial iridium oxides (IrO2); besides, the operando electrochemical impedance spectroscopy (EIS) indicates a better resistance towards surface reconstruction than Co@3DPC leading to a superior stability. A Pt-like oxygen reduction reaction (ORR) performance, half-wave potential associated with kinetic current density, is achieved for Co-CoTe@3DPC. A maximum power density of 203 mW cm-2 is achieved and sustains for 800 h. Furthermore, the all-solid-state ZAB offers 97 mW cm-2. Theoretical calculation suggests that the incorporation of metallic Co to CoTe maintains the superb ORR activity and promotes the OER catalysis.
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Li Y, Li J, Wang B, Jing Q, Zeng Y, Hou A, Wang Z, Liu A, Zhang J, Zhang Y, Zhang P, Jiang D, Liu B, Fan J, Zhang J, Li L, Su G, Yang M, Jiang W, Qu P, Zeng H, Li L, Qiu M, Ru L, Chen S, Zhou Y, Qiao S, Stone GW, Angiolillo DJ, Han Y. Extended Clopidogrel Monotherapy vs DAPT in Patients With Acute Coronary Syndromes at High Ischemic and Bleeding Risk: The OPT-BIRISK Randomized Clinical Trial. JAMA Cardiol 2024; 9:523-531. [PMID: 38630489 PMCID: PMC11024736 DOI: 10.1001/jamacardio.2024.0534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 02/02/2024] [Indexed: 04/20/2024]
Abstract
Importance Purinergic receptor P2Y12 (P2Y12) inhibitor monotherapy after a certain period of dual antiplatelet therapy (DAPT) may be an attractive option of maintenance antiplatelet treatment for patients undergoing percutaneous coronary intervention (PCI) who are at both high bleeding and ischemic risk (birisk). Objective To determine if extended P2Y12 inhibitor monotherapy with clopidogrel is superior to ongoing DAPT with aspirin and clopidogrel after 9 to 12 months of DAPT after PCI in birisk patients with acute coronary syndromes (ACS). Design, Setting, and Participants This was a multicenter, double-blind, placebo-controlled, randomized clinical trial including birisk patients with ACS who had completed 9 to 12 months of DAPT after drug-eluting stent implantation and were free from adverse events for at least 6 months at 101 China centers between February 2018 and December 2020. Study data were analyzed from April 2023 to May 2023. Interventions Patients were randomized either to clopidogrel plus placebo or clopidogrel plus aspirin for an additional 9 months. Main Outcomes and Measures The primary end point was Bleeding Academic Research Consortium (BARC) types 2, 3, or 5 bleeding 9 months after randomization. The key secondary end point was major adverse cardiac and cerebral events (MACCE; the composite of all-cause death, myocardial infarction, stroke or clinically driven revascularization). The primary end point was tested for superiority, and the MACCE end point was tested for sequential noninferiority and superiority. Results A total of 7758 patients (mean [SD] age, 64.8 [9.0] years; 4575 male [59.0%]) were included in this study. The primary end point of BARC types 2, 3, or 5 bleeding occurred in 95 of 3873 patients (2.5%) assigned to clopidogrel plus placebo and 127 of 3885 patients (3.3%) assigned to clopidogrel plus aspirin (hazard ratio [HR], 0.75; 95% CI, 0.57-0.97; difference, -0.8%; 95% CI, -1.6% to -0.1%; P = .03). The incidence of MACCE was 2.6% (101 of 3873 patients) in the clopidogrel plus placebo group and 3.5% (136 of 3885 patients) in the clopidogrel plus aspirin group (HR, 0.74; 95% CI, 0.57-0.96; difference, -0.9%; 95% CI, -1.7% to -0.1%; P < .001 for noninferiority; P = .02 for superiority). Conclusions and Relevance Among birisk patients with ACS who completed 9 to 12 months of DAPT after drug-eluting stent implantation and were free from adverse events for at least 6 months before randomization, an extended 9-month clopidogrel monotherapy regimen was superior to continuing DAPT with clopidogrel in reducing clinically relevant bleeding without increasing ischemic events. Trial Registration ClinicalTrials.gov Identifier: NCT03431142.
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Liu J, Li Y, Andersson HC, Upadia J. Subtelomeric microdeletion in chromosome 20p13 associated with short stature. Clin Case Rep 2024; 12:e8927. [PMID: 38863865 PMCID: PMC11164670 DOI: 10.1002/ccr3.8927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 04/25/2024] [Indexed: 06/13/2024] Open
Abstract
Key Clinical Message Among the total 10 reported cases with 20p13 microdeletion, including our patient, it is notable that 50% of patients presented a height below the 3rd percentile. We suggest that short stature is among the most common manifestations in patients with 20p13 subtelomeric microdeletion. Abstract Chromosome 20p13 microdeletion occurs rarely, with only 10 reported cases. We report a 16-year-old male with a 1.59 Mb terminal deletion in chromosome 20p13, who presented with proportionate short stature, mild language delay, mild learning disability, and delayed puberty. The clinical phenotype associated with this deletion can exhibit clinical variability. Our patient deviates from the typical developmental and intellectual phenotype seen in the 20p13 deletion, instead displaying mild speech delay, short stature, and delayed puberty. The CSNK2A1 deletion, leading to haploinsufficiency, might be the potential mechanism. And the prominence of his proportionate short stature provides a unique perspective to review the existing literature.
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Wu H, Zhang Z, Cao Y, Hu Y, Li Y, Zhang L, Cao X, Wen H, Zhang Y, Lv H, Jin X. A Self-Amplifying ROS-Responsive Nanoplatform for Simultaneous Cuproptosis and Cancer Immunotherapy. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2401047. [PMID: 38569217 DOI: 10.1002/advs.202401047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/21/2024] [Indexed: 04/05/2024]
Abstract
Cuproptosis is an emerging cell death pathway that depends on the intracellular Cu ions. Elesclomol (ES) as an efficient Cu ionophore can specifically transport Cu into mitochondria and trigger cuproptosis. However, ES can be rapidly removed and metabolized during intravenous administration, leading to a short half-life and limited tumor accumulation, which hampers its clinical application. Here, the study develops a reactive oxygen species (ROS)-responsive polymer (PCP) based on cinnamaldehyde (CA) and polyethylene glycol (PEG) to encapsulate ES-Cu compound (EC), forming ECPCP. ECPCP significantly prolongs the systemic circulation of EC and enhances its tumor accumulation. After cellular internalization, the PCP coating stimulatingly dissociates exposing to the high-level ROS, and releases ES and Cu, thereby triggering cell death via cuproptosis. Meanwhile, Cu2+-stimulated Fenton-like reaction together with CA-stimulated ROS production simultaneously breaks the redox homeostasis, which compensates for the insufficient oxidative stress treated with ES alone, in turn inducing immunogenic cell death of tumor cells, achieving simultaneous cuproptosis and immunotherapy. Furthermore, the excessive ROS accelerates the stimuli-dissociation of ECPCP, forming a positive feedback therapy loop against tumor self-alleviation. Therefore, ECPCP as a nanoplatform for cuproptosis and immunotherapy improves the dual antitumor mechanism of ES and provides a potential optimization for ES clinical application.
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Lin J, Chen X, Li Y, Yu L, Chen Y, Zhang B. A dual-targeting therapeutic nanobubble for imaging-guided atherosclerosis treatment. Mater Today Bio 2024; 26:101037. [PMID: 38586870 PMCID: PMC10995877 DOI: 10.1016/j.mtbio.2024.101037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 03/05/2024] [Accepted: 03/19/2024] [Indexed: 04/09/2024] Open
Abstract
Atherosclerosis is a cardiovascular disease that seriously endangers human health. Low shear stress (LSS) is recognized as a vital factor in causing chronic inflammatory and further inducing the occurrence and development of atherosclerosis. Targeting imaging and treatment are of substantial significance for the diagnosis and therapy of atherosclerosis. On this ground, a kind of ultrasound (US) imaging-guided therapeutic polymer nanobubbles (NBs) with dual targeting of magnetism and antibody was rationally designed and constructed for the efficiently treating LSS-mediated atherosclerosis. Under the combined targeting effect of an external magnetic field and antibodies, the drug-loaded therapeutic NBs can be effectively accumulated in the inflammatory area caused by LSS. Upon US irradiation, the NBs can be selectively disrupted, leading to the rapid release of the loaded drugs at the targeted site. Notably, the US irradiation generates a cavitation effect that induces repairable micro gaps in nearby cells, thereby enhancing the uptake of released drugs and further improving the therapeutic effect. The prominent US imaging, efficient anti-inflammatory effect and treatment outcome of LSS-mediated atherosclerosis had been verified in vivo on a surgically constructed LSS-atherosclerosis animal model. This work showcased the potential of the designed NBs with multifunctionality for in vivo imaging, dual-targeting, and drug delivery in the treatment of atherosclerosis.
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Chen W, Bai Y, Fang P, Chen J, Wang X, Li Y, Luo X, Xiao Z, Iyer R, Shan F, Yuan T, Wu M, Huang X, Fang D, Yang Q, Zhang Y. Body mass index’s effect on CRSwNP extends to pathological endotype and recurrence. Rhinology 2024; 62:370-382. [PMID: 38416065 DOI: 10.4193/rhin23.402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
BACKGROUND Elevated body mass index (BMI) has been recognized as an important contributor to corticosteroid insensitivity in chronic rhinosinusitis with nasal polyps (CRSwNP). We aimed to delineate the effects of elevated BMI on immunological endotype and recurrence in CRSwNP individuals. METHODOLOGY A total of 325 patients with CRSwNP undergoing FESS were recruited and stratified by BMI. H&E staining was employed for histological evaluation. Characteristics of inflammatory patterns were identified by immunohistochemical staining. The predictive factors for recurrence were determined and evaluated by multivariable logistic regression analysis and the receiver operating characteristic (ROC) curves across all subjects and by weight group. RESULTS In all patients with CRSwNP, 26.15% subjects were classified as overweight/obese group across BMI categories and exhibited a higher symptom burden. The upregulated eosinophil/neutrophil-dominant cellular endotype and amplified type 2/ type 3 coexisting inflammation was present in overweight/obese compared to underweight/normal weight controls. Additionally, a higher recurrent proportion was shown in overweight/obese patients than that in underweight/normal weight cohorts. Multivariable logistic regression analysis identified BMI as an independent predictor for recurrence. The predictive capacity of each conventional parameter (tissue eosinophil and CLCs count, and blood eosinophil percentage) alone or in combination was poor in overweight/obese subjects. CONCLUSIONS Overweight/obese CRSwNP stands for a unique phenotype and endotype. Conventional parameters predicting recurrence are compromised in overweight/obese CRSwNP, and there is an urgent need for novel biomarkers that predict recurrence for these patients.
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Li Y, Guo C, Chen Q, Su Y, Guo H, Liu R, Sun C, Chen D. Corrigendum to "Improvement of pneumonia by curcumin-loaded bionanosystems based on platycodon grandiflorum polysaccharides via calming cytokine storme" [Int. J. Biol. Macromol. Volume 202, 31 March 2022, pages 691-706. Int J Biol Macromol 2024; 270:132201. [PMID: 38761698 DOI: 10.1016/j.ijbiomac.2024.132201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2024]
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Jia Q, Li J, Guo X, Li Y, Wu Y, Peng Y, Fang Z, Zhang X. Neuroprotective effects of chaperone-mediated autophagy in neurodegenerative diseases. Neural Regen Res 2024; 19:1291-1298. [PMID: 37905878 DOI: 10.4103/1673-5374.385848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 07/17/2023] [Indexed: 11/02/2023] Open
Abstract
ABSTRACT Chaperone-mediated autophagy is one of three types of autophagy and is characterized by the selective degradation of proteins. Chaperone-mediated autophagy contributes to energy balance and helps maintain cellular homeostasis, while providing nutrients and support for cell survival. Chaperone-mediated autophagy activity can be detected in almost all cells, including neurons. Owing to the extreme sensitivity of neurons to their environmental changes, maintaining neuronal homeostasis is critical for neuronal growth and survival. Chaperone-mediated autophagy dysfunction is closely related to central nervous system diseases. It has been shown that neuronal damage and cell death are accompanied by chaperone-mediated autophagy dysfunction. Under certain conditions, regulation of chaperone-mediated autophagy activity attenuates neurotoxicity. In this paper, we review the changes in chaperone-mediated autophagy in neurodegenerative diseases, brain injury, glioma, and autoimmune diseases. We also summarize the most recent research progress on chaperone-mediated autophagy regulation and discuss the potential of chaperone-mediated autophagy as a therapeutic target for central nervous system diseases.
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Liu J, Fang X, Cao S, Shi Y, Li S, Liu H, Li Y, Xu S, Xia W. Associations of ambient temperature and total cloud cover during pregnancy with newborn vitamin D status. Public Health 2024; 231:179-186. [PMID: 38703492 DOI: 10.1016/j.puhe.2024.03.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 02/24/2024] [Accepted: 03/27/2024] [Indexed: 05/06/2024]
Abstract
OBJECTIVES We aimed to estimate the effects of temperature and total cloud cover before birth on newborn vitamin D status. STUDY DESIGN Prospective birth cohort. METHODS This study included 2055 mother-newborn pairs in Wuhan, Hubei province, China. The data of temperature and total cloud cover from 30 days before birth were collected, and cord blood 25-hydroxyvitamin D [25(OH)D] were determined. Restricted cubic spline regression models, multiple linear regression models, and logistic regression models were applied to estimate the associations. RESULTS A "J" shaped curve was observed between temperature and vitamin D status, and an inverse "J" shaped curve was observed between total cloud cover and vitamin D status. Compared to the fourth quartile (75-100th percentile, Q4) of average temperature (30 days before birth), the odds ratio (OR) for Q1 (0-25th percentile) associated with the vitamin D deficiency occurrence (<20 ng/mL) was 3.63 (95% CI, 1.54, 8.65). Compared to Q1 of the average total cloud cover (30 days before birth), the OR associated with the occurrence of vitamin D deficiency was 2.38 (95% CI, 1.63, 3.50) for the Q4. CONCLUSIONS Low temperature and high cloud cover before delivery were significantly associated with an increased probability of vitamin D deficiency in newborns. The findings suggested that pregnancy women lacking sufficient sunlight exposure still need vitamin D supplement to overcome the potential vitamin D deficiency status.
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Zhu C, Wang Y, Li Y, Wang T, Ye F, Su W, Chen T, Zhang C, Xiong L. Discovery of neuroprotective Agents: Potent, brain Penetrating, lipoic acid derivatives for the potential treatment of ischemic stroke by regulating oxidative stress and inflammation - a Preliminary study. Bioorg Chem 2024; 147:107339. [PMID: 38643566 DOI: 10.1016/j.bioorg.2024.107339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/02/2024] [Accepted: 04/04/2024] [Indexed: 04/23/2024]
Abstract
Stroke poses a serious risk to the physical and mental health of patients. Endogenous compounds are widely used to treat ischemic stroke. Lipoic acid, a naturally occurring (R)-5-(1,2-dithiolan-3-yl)pentanoic acid, has therapeutic potential for the treatment of ischemic stroke. However, the direct application of lipoic acid is limited by its relatively low efficacy and instability. Therefore, there is a need to modify the structure of lipoic acid to improve its pharmaceutical capabilities. Currently, 37 lipoic acid derivatives have been synthesized, and compound AA-9 demonstrated optimal therapeutic potential in an in vitro model of induced oxidative damage using tert-butyl hydroperoxide (t-BHP). In addition, in vitro experiments have shown that compound AA-9 has an excellent safety profile. Subsequently, the therapeutic effect of AA-9 was significant in the rat MCAO ischemic stroke model, which may be attributed to the antioxidant and anti-inflammatory effects of compound AA-9 by activating PGC-1α and inhibiting NLRP3. Notably, compound AA-9 exhibited higher stability and better bioavailability properties than ALA in plasma stability and pharmacokinetic properties. In conclusion, AA-9 may be a promising neuroprotective agent for the treatment of ischemic stroke and warrants further investigation.
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Li Y, Tong WD. Association between dietary protein intake and constipation: Data from the National Health and nutrition examination survey 2005-2010. Neurogastroenterol Motil 2024; 36:e14795. [PMID: 38651659 DOI: 10.1111/nmo.14795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 03/25/2024] [Accepted: 04/03/2024] [Indexed: 04/25/2024]
Abstract
BACKGROUND The association between dietary protein intake and constipation remains inconclusive. The aim of this study was to investigate whether dietary protein intake is associated with constipation. METHODS This cross-sectional study included 13,941 adults from the 2005 to 2010 National Health and Nutrition Examination Survey. A weighted logistic regression analysis was used to control for confounding factors. In addition, weighted interaction and stratified analyses were conducted to ascertain the potential modifying factors. RESULTS The prevalence of constipation was 7.5% when constipation was defined by stool consistency and 3.5% when constipation was defined by stool frequency. After adjusting for covariates, an increase in dietary protein intake of 10 g was not associated with constipation, as defined by stool frequency (OR = 0.94, 95% CI = 0.54, 1.62) or stool consistency (OR = 1.02, 95% CI = 0.75, 1.39). Subgroup analyses revealed that dietary protein intake was associated with an increase in constipation defined by stool consistency risk in participants who consumed a low amount of carbohydrates (OR = 1.08, 95% CI = 1.02-1.14 for every 10-g increase in protein intake), but a decrease in risk in participants in the moderate-carbohydrate group (OR = 0.94, 95% CI = 0.89-0.99 for every 10-g increase in protein intake), suggesting a significant interaction (p = 0.001). CONCLUSION & INFERENCES Dietary protein intake is not associated with stool consistency or frequency-defined constipation. However, the association between dietary protein intake and constipation defined by stool consistency in participants with a low carbohydrate intake differed from that in participants with a moderate carbohydrate intake.
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Liang Y, Wang F, Song Y, Tang C, Wu R, Feng Q, Han M, Li Y, Chen W, Zhang J, Jiang M, Wang Z. LC-MS based metabonomics study on protective mechanism of ESWW in cerebral ischemia via CYTC/Apaf-1/NDRG4 pathway. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2024; 128:155543. [PMID: 38657364 DOI: 10.1016/j.phymed.2024.155543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Revised: 03/07/2024] [Accepted: 03/16/2024] [Indexed: 04/26/2024]
Abstract
BACKGROUND Ershiwuwei Zhenzhu pills was originally recorded in the Tibetan medical book Si Bu Yi Dian in the 8th century AD and is now included in the Pharmacopoeia of the People's Republic of China (2020). The pills can calm the nerves and open the mind as well as treat cerebral ischemia reperfusion injury, stroke, hemiplegia. However, its quality standards have not yet been established, and the therapeutic effect on cerebral ischemia by regulating the mitochondrial apoptosis pathway has not been elucidated. STUDY DESIGN AND METHODS LC-MS was used to establish quality standards for Ershiwuwei Zhenzhu pills. Metabonomics, molecular docking, neuroethology, cerebral infarction ratio, pathological detection of diencephalon, cortex, and hippocampus, and molecular biology techniques were used to reveal the mechanism of the pills in regulating the mitochondrial apoptosis pathway to treat cerebral ischemia. RESULTS The contents of 20 chemical components in Ershiwuwei Zhenzhu pills from 12 batches and 8 manufacturers was determined for the first time. Eleven differential metabolites and three metabolic pathways, namely, fructose and mannose metabolism, glycerophospholipid metabolism, and purine metabolism, were identified by metabonomics. The pills improved the neuroethology abnormalities of MCAO rats and the pathological damage in the diencephalon and decreased the ratio of cerebral infarction. It also significantly reduced the mRNA expression of AIF, Apaf-1, cleared caspase8, CytC, and P53 mRNA in the brain tissue and the protein expression of Apaf-1 and CYTC and increased the protein expression of NDRG4. CONCLUSION In vitro quantitative analysis of the in vitro chemical components of Ershiwuwei Zhenzhu pills has laid the foundation for improving its quality control. The potential mechanism of the pills in treating cerebral ischemia may be related to the Apaf-1/CYTC/NDRG4 apoptosis pathway. This work provides guidance for clinical drug use for patients.
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Jiang S, Guo S, Huang Y, Xu J, Li Y, Zeng Y, Guo Y, Ouyang L, Zhu C, Zhao W, Zhang Q, Guo Q, Xin H, Xie Q. Interim analysis of the PARADISE study: Benefits of add-on peginterferon-α in NA-treated patients with CHB. Antiviral Res 2024; 226:105892. [PMID: 38663455 DOI: 10.1016/j.antiviral.2024.105892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 04/13/2024] [Accepted: 04/20/2024] [Indexed: 04/29/2024]
Abstract
This study aimed to investigate whether peginterferon-α (IFN) add-on nucleos(t)ide analogs(NAs) can further reduce hepatocellular carcinoma(HCC) risk compared with NAs monotherapy in NA-treated patients with chronic hepatitis B(CHB). In this multi-center randomized controlled trial "PARADISE study" (NCT05671315), CHB patients with intermediate to high risk of HCC after more than 24-week NAs pretreatment were recruited, randomized to two groups at a ratio of 1:2 and followed up for 240 weeks. NAs group maintained NAs monotherapy, while IFN + NAs group received IFN add-on NAs therapy for 48 weeks, then switched to NAs monotherapy. Totally, 196 patients were included in interim analysis (NAs group 68, IFN + NAs group 128). The 96-week cumulative HCC incidence was lower in IFN + NAs group than NAs group (0% vs. 4.5%, p < 0.05). Compared with NAs group, IFN + NAs group had significantly higher rates of HBsAg loss at week 48 and 96 (22.7% vs. 0%; 16.7% vs. 0%, both p < 0.05). A new scoring system was established to predict HBsAg decline >2log10 IU/ml, HBsAg <10 IU/ml or HBsAg loss at the end of 48-week IFN treatment. The area under ROC curve was 0.914, 0.922 or 0.905 in the original cohort (n = 128) and 0.896, 0.896 or 0.864 in the external validation cohort (n = 162) for the aforementioned three outcomes, respectively. IFN add-on NAs therapy may suggest the dual benefits of reducing HCC development and facilitating HBsAg loss among NA-treated CHB patients with intermediate to high risk of HCC. The new scoring system helps to make the most of IFN treatment for a higher cost-effectiveness in healthcare.
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Zhou L, Butler TA, Wang XH, Xi K, Tanzi EB, Glodzik L, Chiang GC, de Leon MJ, Li Y. Multimodal assessment of brain fluid clearance is associated with amyloid-beta deposition in humans. J Neuroradiol 2024; 51:101164. [PMID: 37907155 PMCID: PMC11058119 DOI: 10.1016/j.neurad.2023.10.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 10/09/2023] [Accepted: 10/28/2023] [Indexed: 11/02/2023]
Abstract
PURPOSE The present study investigates a multimodal imaging assessment of glymphatic function and its association with brain amyloid-beta deposition. METHODS Two brain CSF clearance measures (vCSF and DTI-ALPS) were derived from dynamic PET and MR diffusion tensor imaging (DTI) for 50 subjects, 24/50 were Aβ positive (Aβ+). T1W, T2W, DTI, T2FLAIR, and 11C-PiB and 18F-MK-6240 PET were acquired. Multivariate linear regression models were assessed with both vCSF and DTI-ALPS as independent variables and brain Aβ as the dependent variable. Three types of models were evaluated, including the vCSF-only model, the ALPS-only model and the vCSF+ALPS combined model. Models were applied to the whole group, and Aβ subgroups. All analyses were controlled for age, gender, and intracranial volume. RESULTS Sample demographics (N=50) include 20 males and 30 females with a mean age of 69.30 (sd=8.55). Our results show that the combination of vCSF and ALPS associates with Aβ deposition (p < 0.05, R2 = 0.575) better than either vCSF (p < 0.05, R2 = 0.431) or ALPS (p < 0.05, R2 = 0.372) alone in the Aβ+ group. We observed similar results in whole-group analyses (combined model: p < 0.05, R2 = 0.287; vCSF model: p <0.05, R2 = 0.175; ALPS model: p < 0.05, R2 = 0.196) with less significance. Our data also showed that vCSF has higher correlation (r = -0.548) in subjects with mild Aβ deposition and DTI-ALPS has higher correlation (r=-0.451) with severe Aβ deposition subjects. CONCLUSION The regression model with both vCSF and DTI-ALPS is better associated with brain Aβ deposition. These two independent brain clearance measures may better explain the variation in Aβ deposition than either term individually. Our results suggest that vCSF and DTI-ALPS reflect complementary aspects of brain clearance functions.
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95
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Qin M, Han S, Chen M, Li P, Wang Y, Niu W, Gao C, Wang H, Li Y. Biofilm formation of Hafnia paralvei induced by c-di-GMP through facilitating bcsB gene expression promotes spoilage of Yellow River carp (Cyprinus carpio). Food Microbiol 2024; 120:104482. [PMID: 38431313 DOI: 10.1016/j.fm.2024.104482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 01/26/2024] [Accepted: 01/29/2024] [Indexed: 03/05/2024]
Abstract
Hafnia paralvei, a Gram-negative foodborne pathogen, is found ubiquitously in various aquatic animals and seafoods, which can form biofilm as a dominant virulence factor that contributes to its pathogenesis. However, the biofilm formation mechanism of H. paralvei and its effect on food spoilage has not been fully characterized. Here we show that biofilm formation, is regulated by c-di-GMP which mediated by bcsB, can increase the spoilage ability of H. paralvei. We found that GTP was added exogenously to enhance the synthesis of c-di-GMP, which further promoted biofilm formation. The gene dgcC, one of 11 genes encoding GGDEF domain-containing proteins in H. paralvei, was significantly upregulated with GTP as substrate. The upregulation of dgcC contributes to a significant increase of c-di-GMP and the formation of biofilm. In addition, the overexpression of dgcC induced upregulation of bcsB, a reported effector protein encoding gene, which was further demonstrated that overexpression of bcsB can encourage the synthesis of bacterial cellulose and biofilm formation. The effect of biofilm formation induced by c-di-GMP on spoilage of Yellow River carp (Cyprinus carpio) was evaluated by sensory evaluation, the total viable count, and the total volatile basic nitrogen, which showed that biofilm formation can significantly increase the spoilage ability of H. paralvei on C. carpio. Our findings provide the regulation of c-di-GMP on expression of bcsB, that can contribute to biofilm formation and spoilage ability of H. paralvei, which is favor to understanding the pathogenesis of Hafnia paralvei and its role in food spoilage.
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Xiao J, Tan J, Guo R, Dai J, Xiu Z, Sun Y, Liu H, Li Y, Tong Y, Quan C. Deoxynivalenol Detoxification by a Novel Strain of Pichia kudriavzevii via Enzymatic Degradation and Cell Wall Adsorption. Appl Biochem Biotechnol 2024; 196:3102-3114. [PMID: 37624506 DOI: 10.1007/s12010-023-04712-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/16/2023] [Indexed: 08/26/2023]
Abstract
Deoxynivalenol (DON) is a mycotoxin that significantly threatens the food and feed industry. Corn steep liquor (CSL) is an acidic byproduct of the corn starch industry, and DON is concentrated in CSL once the material is contaminated. In this work, a Pichia kudriavzevii strain that could remove DON from CSL was isolated and characterized. The strain P. kudriavzevii E4-205 showed detoxifying activity in a pH range of 4.0~7.0 and temperature of 25~42 °C, and 39.4% DON was reduced by incubating this strain in CSL supernatant diluted by 2-fold (5 μg/mL DON) for 48 h at pH 5.0 and 30 °C. Further mechanism studies showed that P. kudriavzevii E4-205 could adsorb DON by the cell wall and degrade DON by intracellular enzymes with NADH as a cofactor. The degradation product was identified as 3,7,8,15-tetrahydroxyscirpene by liquid chromatography-tandem mass spectrometry. DON adsorption by inactivated cells was characterized, and the adsorption followed pseudo first-order kinetics. This study revealed a novel mechanism by which microbes degrade DON and might serve as a guide for the development of DON biological detoxification methods.
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Li Y, Li Y, Guo Y, Chen C, Yang L, Jiang Q, Ling P, Wang S, Li L, Fang J. Enzymatic modular synthesis of asymmetrically branched human milk oligosaccharides. Carbohydr Polym 2024; 333:121908. [PMID: 38494200 DOI: 10.1016/j.carbpol.2024.121908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 01/07/2024] [Accepted: 01/31/2024] [Indexed: 03/19/2024]
Abstract
Human milk oligosaccharides (HMOs) are intricate glycans that promote healthy growth of infants and have been incorporated into infant formula as food additives. Despite their importance, the limited availability of asymmetrically branched HMOs hinders the exploration of their structure and function relationships. Herein, we report an enzymatic modular strategy for the efficient synthesis of these HMOs. The key branching enzyme for the assembly of branched HMOs, human β1,6-N-acetylglucosaminyltransferase 2 (GCNT2), was successfully expressed in Pichia pastoris for the first time. Then, it was integrated with six other bacterial glycosyltransferases to establish seven glycosylation modules. Each module comprises a one-pot multi-enzyme (OPME) system for in-situ generation of costly sugar nucleotide donors, combined with a glycosyltransferase for specific glycosylation. This approach enabled the synthesis of 31 branched HMOs and 13 linear HMOs in a stepwise manner with well-programmed synthetic routes. The binding details of these HMOs with related glycan-binding proteins were subsequently elucidated using glycan microarray assays to provide insights into their biological functions. This comprehensive collection of synthetic HMOs not only serves as standards for HMOs structure identification in complex biological samples but also significantly enhances the fields of HMOs glycomics, opening new avenues for biomedical applications.
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Wang T, Wang J, Tang T, Li Q, Li Y, Song X. Surgery for adult head and neck rhabdomyosarcoma: A retrospective report from one institution. Int Forum Allergy Rhinol 2024; 14:1110-1114. [PMID: 38153372 DOI: 10.1002/alr.23313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/07/2023] [Accepted: 12/08/2023] [Indexed: 12/29/2023]
Abstract
KEY POINTS Surgery in adults with head and neck rhabdomyosarcoma does not improve survival rates. Surgery should be performed deliberately and focused on the timing of combined treatment modality. Adult head and neck rhabdomyosarcoma benefits from salvage surgery following chemoradiotherapy.
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Wu H, Zhou P, Song X, Sun W, Li Y, Song S, Zhang Y. Dynamics of solar-induced chlorophyll fluorescence (SIF) and its response to meteorological drought in the Yellow River Basin. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 360:121023. [PMID: 38733837 DOI: 10.1016/j.jenvman.2024.121023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 04/06/2024] [Accepted: 04/24/2024] [Indexed: 05/13/2024]
Abstract
Solar-induced chlorophyll fluorescence (SIF) has been used since its discovery to characterize vegetation photosynthesis and is an effective tool for monitoring vegetation dynamics. Its response to meteorological drought enhances our comprehension of the ecological consequences and adaptive mechanisms of plants facing water scarcity, informing more efficient resource management and efforts in mitigating climate change. This study investigates the spatial and temporal patterns of SIF and examines how vegetation SIF in the Yellow River Basin (YRB) responds to meteorological drought. The findings reveal a gradual southeast-to-northwest decline in SIF across the Yellow River Basin, with an overall increase-from 0.1083 W m-2μm-1sr-1 in 2001 to 0.1468 W m-2μm-1sr-1 in 2019. Approximately 96% of the YRB manifests an upward SIF trend, with 75% of these areas reaching statistical significance. The Standardized Precipitation Evapotranspiration Index (SPEI) at a time scale of 4 months (The SPEI-4), based on the Liang-Kleeman information flow method, is identified as the most suitable drought index, adeptly characterizing the causal relationship influencing SIF variations. As drought intensified, the SPEI-4 index markedly deviated from the baseline, resulting in a decrease in SIF values to their lowest value; subsequently, as drought lessened, it gravitated towards the baseline, and SIF values began to gradually increase, eventually recovering to near their annual maximum. The key finding is that the variability of SIF with SPEI is relatively pronounced in the early growing season, with forests demonstrating superior resilience compared to grasslands and croplands. The responsiveness of vegetation SIF to SPEI can facilitate the establishment of effective drought early warning systems and promote the rational planning of water resources, thereby mitigating the impacts of climate change.
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Zhang J, Hou C, Zhao TL, Shi K, Li Y, Wang Y, Zhou M, Sun X, Quan Y, Li Z, Yang Y, Fei C. 0.36BiScO 3-0.64PbTiO 3/Epoxy 1-3-2 High- Temperature Composite Ultrasonic Transducer for Nondestructive Testing Applications. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2024; 71:638-647. [PMID: 38648136 DOI: 10.1109/tuffc.2024.3388552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
The development of high-temperature nondestructive testing (NDT) requires ultrasonic transducers with good temperature resistance and high sensitivity for improved detection efficiency. Piezoelectric composite can improve the performance of transducers because of its high electromechanical coupling coefficient and adjustable acoustic impedance. In this study, 1-3-2 composites and 1-3-2 high-temperature composite ultrasonic transducers (HTCUTs) based on 0.36BiScO3-0.64PbTiO3 (BSPT), which is preferred piezoelectric materials at 200 ° C- 300 ° C, and high-temperature epoxy with a center frequency of 6 MHz were designed and fabricated. From 25 ° C to 250 ° C, 1-3-2 composites show a higher electromechanical coupling coefficient kt especially at high temperatures (~0.53 at 25 ° C and ~0.64 at 250 ° C) than monolithic BSPT (~0.5). The signal of the pulse-echo response of 1-3-2 HTCUTs is distinguishable up to 250 ° C and remains stable ( [Formula: see text] mV) below 150 ° C, exhibiting higher sensitivity (improved by 7 dB) than that of monolithic BSPT high-temperature ultrasonic transducers (HTUTs). Bandwidth has been greatly enhanced especially at high temperatures (~103% at 250 ° C) compared with that of monolithic BSPT HTUTs (~30% at 250 ° C). To verify the excellent performance, B-mode scanning imaging measurement of a stepped steel block and defect location detection of a steel block was performed, showing the potential for high-temperature NDT applications.
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