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1.
Magn Reson Med ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38968132

ABSTRACT

PURPOSE: To reduce the ringing artifacts of the motion-resolved images in free-breathing dynamic pulmonary MRI. METHODS: A golden-step based interleaving (GSI) technique was proposed to reduce ringing artifacts induced by diaphragm drifting. The pulmonary MRI data were acquired using a superior-inferior navigated 3D radial UTE sequence in an interleaved manner during free breathing. Successive interleaves were acquired in an incoherent fashion along the polar direction. Four-dimensional images were reconstructed from the motion-resolved k-space data obtained by retrospectively binning. The reconstruction algorithms included standard nonuniform fast Fourier transform (NUFFT), Voronoi-density-compensated NUFFT, extra-dimensional UTE, and motion-state weighted motion-compensation reconstruction. The proposed interleaving technique was compared with a conventional sequential interleaving (SeqI) technique on a phantom and eight subjects. RESULTS: The quantified ringing artifacts level in the motion-resolved image is positively correlated with the quantified nonuniformity level of the corresponding k-space. The nonuniformity levels of the end-expiratory and end-inspiratory k-space binned from GSI data (0.34 ± 0.07, 0.33 ± 0.05) are significantly lower with statistical significance (p < 0.05) than that binned from SeqI data (0.44 ± 0.11, 0.42 ± 0.12). Ringing artifacts are substantially reduced in the dynamic images of eight subjects acquired using the proposed technique in comparison with that acquired using the conventional SeqI technique. CONCLUSION: Ringing artifacts in the motion-resolved images induced by diaphragm drifting can be reduced using the proposed GSI technique for free-breathing dynamic pulmonary MRI. This technique has the potential to reduce ringing artifacts in free-breathing liver and kidney MRI based on full-echo interleaved 3D radial acquisition.

2.
Mikrochim Acta ; 191(8): 466, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39017814

ABSTRACT

The CRISPR/Cas13 nucleases have been widely documented for nucleic acid detection. Understanding the intricacies of CRISPR/Cas13's reaction components is pivotal for harnessing its full potential for biosensing applications. Herein, we report on the influence of CRISPR/Cas13a reaction components on its trans-cleavage activity and the development of an on-chip total internal reflection fluorescence microscopy (TIRFM)-powered RNA sensing system. We used SARS-CoV-2 synthetic RNA and pseudovirus as a model system. Our results show that optimizing Mg2+ concentration, reporter length, and crRNA combination significantly improves the detection sensitivity. Under optimized conditions, we detected 100 fM unamplified SARS-CoV-2 synthetic RNA using a microtiter plate reader. To further improve sensitivity and provide a new amplification-free RNA sensing toolbox, we developed a TIRFM-based amplification-free RNA sensing system. We were able to detect RNA down to 100 aM. Furthermore, the TIRM-based detection system developed in this study is 1000-fold more sensitive than the off-coverslip assay. The possible clinical applicability of the system was demonstrated by detecting SARS-CoV-2 pseudovirus RNA. Our proposed sensing system has the potential to detect any target RNA with slight modifications to the existing setup, providing a universal RNA detection platform.


Subject(s)
CRISPR-Cas Systems , RNA, Viral , SARS-CoV-2 , SARS-CoV-2/genetics , RNA, Viral/analysis , RNA, Viral/genetics , Humans , COVID-19/diagnosis , COVID-19/virology , Biosensing Techniques/methods , CRISPR-Associated Proteins , Microscopy, Fluorescence , Lab-On-A-Chip Devices , Limit of Detection , Magnesium/chemistry , COVID-19 Nucleic Acid Testing/methods
3.
Sci Rep ; 14(1): 15646, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38977703

ABSTRACT

Gamma knife radiosurgery (GKRS) is recommended as the first-line treatment for brain metastases of lung adenocarcinoma (LUAD) in many guidelines, but its specific mechanism is unclear. We aimed to study the changes in the proteome of brain metastases of LUAD in response to the hyperacute phase of GKRS and further explore the mechanism of differentially expressed proteins (DEPs). Cancer tissues were collected from a clinical trial for neoadjuvant stereotactic radiosurgery before surgical resection of large brain metastases (ChiCTR2000038995). Five brain metastasis tissues of LUAD were collected within 24 h after GKRS. Five brain metastasis tissues without radiotherapy were collected as control samples. Proteomics analysis showed that 163 proteins were upregulated and 25 proteins were downregulated. GO and KEGG enrichment analyses showed that the DEPs were closely related to ribosomes. Fifty-three of 70 ribosomal proteins were significantly overexpressed, while none of them were underexpressed. The risk score constructed from 7 upregulated ribosomal proteins (RPL4, RPS19, RPS16, RPLP0, RPS2, RPS26 and RPS25) was an independent risk factor for the survival time of LUAD patients. Overexpression of ribosomal proteins may represent a desperate response to lethal radiotherapy. We propose that targeted inhibition of these ribosomal proteins may enhance the efficacy of GKRS.


Subject(s)
Adenocarcinoma of Lung , Brain Neoplasms , Lung Neoplasms , Proteomics , Radiosurgery , Ribosomal Proteins , Humans , Ribosomal Proteins/metabolism , Radiosurgery/methods , Brain Neoplasms/secondary , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Brain Neoplasms/radiotherapy , Male , Female , Proteomics/methods , Adenocarcinoma of Lung/metabolism , Adenocarcinoma of Lung/pathology , Adenocarcinoma of Lung/mortality , Adenocarcinoma of Lung/surgery , Adenocarcinoma of Lung/radiotherapy , Lung Neoplasms/pathology , Lung Neoplasms/metabolism , Lung Neoplasms/radiotherapy , Middle Aged , Aged , Gene Expression Regulation, Neoplastic , Proteome/metabolism
4.
Transl Cancer Res ; 13(6): 2938-2949, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38988911

ABSTRACT

Background: Laryngeal squamous cell carcinoma (LSCC) prognosis has not improved significantly in the past few decades, and more effective treatments are needed to be explored. Ferroptosis is a newly discovered kind of regulated cell death in recent years, which is related to tumor immunity and can used to treat tumors. Therefore, the prognostic value of ferroptosis-related genes in laryngeal cancer needs further clarification. Methods: In this study, the mRNA expression profile data of LSCC were downloaded from the public database. After identifying ferroptosis-related differentially expressed genes (FDGs), we explored the role of these genes through functional enrichment analysis. FDGs with prognostic significance were identified by univariate Cox and least absolute shrinkage and selection operator (LASSO) regression analyses. By calculating the risk score, we constructed a prognostic model. Kaplan-Meier (K-M) analysis, the receiver operating characteristic (ROC) curves, and the nomogram were utilized to investigate this model. Public databases and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to verify the expression of model genes. Results: The model consisting of four FDGs was acknowledged to be a self-determining predictor of prognosis. The K-M survival curves and the ROC curves confirmed the model's predictive ability. The C index (0.805) indicates that the nomogram has a good predictive ability. In vitro studies have confirmed the differential expression of the four FDGs. Conclusions: We identified a novel ferroptosis-related gene signature for predicting prognosis in LSCC.

5.
J Phys Chem Lett ; 15(27): 6974-6985, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38941557

ABSTRACT

Synaptic transistors have been proposed to implement neuron activation functions of neural networks (NNs). While promising to enable compact, fast, inexpensive, and energy-efficient dedicated NN circuits, they also have limitations compared to digital NNs (realized as codes for digital processors), including shape choices of the activation function using particular types of transistor implementation, and instabilities due to noise and other factors present in analog circuits. We present a computational study of the effects of these factors on NN performance and find that, while accuracy competitive with traditional NNs can be realized for many applications, there is high sensitivity to the instability in the shape of the activation function, suggesting that, when highly accurate NNs are required, high-precision circuitry should be developed beyond what has been reported for synaptic transistors to date.

6.
Epilepsy Behav ; 157: 109870, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38870867

ABSTRACT

OBJECTIVE: To evaluate the incidence and the independent risk factors of SRS-related epilepsy in patients with supratentorial brain metastases (st-BMs), providing evidences for prevention or reduction secondary epilepsy after SRS. METHODS: Patients with st-BMs from four gamma knife centers who developed secondary epilepsy after SRS were retrospectively studied between January 1, 2017 and June 31, 2023. The incidence and clinical characteristics of the patients with secondary epilepsy were analyzed. The predictive role of baseline clinical-demographic variables was evaluated according to univariate and multivariate logistic regression model. The impact of secondary epilepsy on patients' OS was evaluated as well by log-rank test. RESULTS: 11.3 % (126/1120) of the patients with totally 158 st-BMs experienced secondary epilepsy after SRS in median 21 days. 61.9 % (78/126) of the patients experienced simple partial seizures. 91.3 % (115/126) patients achieved good seizure control after received 1-2 kinds of AEDs for median 90 days, while 7.1 % (9/126) of the patients suffered from refractory epilepsy. Patients had higher risk of secondary epilepsy if the tumor located in cortex and/or hippocampus, peri-tumor edema larger than 20.3 cm3 before SRS, had epilepsy history, and failed to receive bevacizumab prior to SRS. There was no difference in the OS of patients who experience secondary epilepsy or not after SRS. CONCLUSIONS: The incidence of SRS-related secondary epilepsy is 11.3 % in patients with st-BMs in this retrospective study. The risk of secondary epilepsy is higher in patients with st-BM located in cortex and/or hippocampus area, peri-tumor edema larger than 20.3 cm3 before SRS, and epilepsy history. Bevacizumab is suggested prior to SRS therapy, as it could be used for the control of peri-tumor edema and SRS-related damage, hence reduce the risk of secondary epilepsy. However, whether or not patients suffered from secondary epilepsy after SRS does not affect their OS.

7.
J Immunother Cancer ; 12(6)2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38871480

ABSTRACT

BACKGROUND: The sustained effectiveness of anti-programmed cell death protein-1/programmed death-ligand 1 treatment is limited to a subgroup of patients with advanced nasopharyngeal carcinoma (NPC), and the specific biomarker determining the response to immunotherapy in NPC remains uncertain. METHODS: We assessed the associations between pre-immunotherapy and post-immunotherapy serum lipoproteins and survival in a training cohort (N=160) and corroborated these findings in a validation cohort (N=100). Animal studies were performed to explore the underlying mechanisms. Additionally, the relationship between high-density lipoprotein-cholesterol (HDL-C) levels and M1/M2-like macrophages, as well as activated CD8+T cells in tumor tissues from patients with NPC who received immunotherapy, was investigated. RESULTS: The lipoproteins cholesterol, HDL-C, low-density lipoprotein-cholesterol, triglycerides, apolipoprotein A-1 (ApoA1), and apolipoprotein B, were significantly altered after immunotherapy. Patients with higher baseline HDL-C or ApoA1, or those with increased HDL-C or ApoA1 after immunotherapy had longer progression-free survival, a finding verified in the validation cohort (p<0.05). Multivariate analysis revealed that baseline HDL-C and elevated HDL-C post-immunotherapy were independent predictors of superior PFS (p<0.05). Furthermore, we discovered that L-4F, an ApoA1 mimetic, could inhibit tumor growth in NPC xenografts. This effect was associated with L-4F's ability to polarize M2-like macrophages towards an M1-like phenotype via the activation of mitogen-activated protein kinase (MAPK) p38 and nuclear factor-κB (NF-κB) p65, thereby alleviating immunosuppression in the tumor microenvironment. Importantly, in patients with NPC with high plasma HDL-C levels, the number of M2-like macrophages was significantly decreased, while M1-like macrophages and activated CD8+T cells were notably increased in those with high HDL-C levels. CONCLUSION: Higher baseline HDL-C levels or an increase in HDL-C post-immunotherapy can enhance immunotherapeutic responses in patients with NPC by reprogramming M2-like macrophages towards the M1 phenotype. This suggests a potential role for prospectively exploring ApoA1 mimetics as adjuvant agents in combination with immunotherapy.


Subject(s)
Cholesterol, HDL , Immunotherapy , Nasopharyngeal Carcinoma , Tumor-Associated Macrophages , Humans , Nasopharyngeal Carcinoma/immunology , Nasopharyngeal Carcinoma/pathology , Nasopharyngeal Carcinoma/therapy , Nasopharyngeal Carcinoma/drug therapy , Tumor-Associated Macrophages/immunology , Tumor-Associated Macrophages/metabolism , Immunotherapy/methods , Animals , Female , Male , Cholesterol, HDL/metabolism , Cholesterol, HDL/blood , Mice , Middle Aged , Phenotype , Tumor Microenvironment , Nasopharyngeal Neoplasms/immunology , Nasopharyngeal Neoplasms/pathology , Nasopharyngeal Neoplasms/therapy , Nasopharyngeal Neoplasms/drug therapy , Adult
8.
J Chem Phys ; 160(23)2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38884408

ABSTRACT

The orientation and rearrangement of water on a gold electrode significantly influences its physicochemical heterogeneous performance. Despite numerous experimental and theoretical studies aimed at uncovering the structural characteristics of interfacial water, the orientational behavior resulting from electrode-induced rearrangements remains a subject of ongoing debate. Here, we employed molecular dynamics simulations to investigate the adaptive structure and dynamics properties of interfacial water on Au(111) and Au(100) surfaces by considering a polarizable model for Au atoms in comparison with the non-polarizable model. Compared to the nonpolarizable systems, the polarization effect can enhance the interaction between water molecules and the gold surface. Unexpectedly, the rotational dynamics directly associated with the orientational behavior of water adjacent to the gold surface is accelerated, thereby reducing the hydrogen bond lifetime. The underlying mechanism for this anomalous phenomenon originates from the polarization effect, which induces the attraction of the positive hydrogen atoms to the surface by the negative image charge. This leads to a change in orientation that disrupts the hydrogen bonds in the first water layer and subsequently accelerates reorientation dynamics of water molecules adjacent to the gold surface. These results shed light on the intricate interplay between polarization effects and water molecule dynamics on metal surfaces, establishing the foundation for the rational regulation of the orientation of interfacial water.

9.
Surgery ; 176(2): 379-385, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38762380

ABSTRACT

BACKGROUND: Sepsis, characterized by dysregulated host responses to infection, remains a critical global health concern, with high morbidity and mortality rates. The gastrointestinal tract assumes a pivotal role in sepsis due to its dual functionality as a protective barrier against injurious agents and as a regulator of motility. Dexmedetomidine, an α2-adrenergic agonist commonly employed in critical care settings, exhibits promise in influencing the maintenance of intestinal barrier integrity during sepsis. However, its impact on intestinal motility, a crucial component of intestinal function, remains incompletely understood. METHODS: In this study, we investigated dexmedetomidine's multifaceted effects on intestinal barrier function and motility during sepsis using both in vitro and in vivo models. Sepsis was induced in Sprague-Dawley rats via cecal ligation and puncture. Rats were treated with dexmedetomidine post-cecal ligation and puncture, and various parameters were assessed to elucidate dexmedetomidine's impact. RESULTS: Our findings revealed a dichotomous influence of dexmedetomidine on intestinal physiology. In septic rats, dexmedetomidine administration resulted in improved intestinal barrier integrity, as evidenced by reduced mucosal hyper-permeability and morphological alterations. However, a contrasting effect was observed on intestinal motility, as dexmedetomidine treatment inhibited both the frequency and amplitude of contractions in isolated intestinal strips and decreased the distance of ink migration in vivo. Additionally, dexmedetomidine suppressed the secretion of pro-motility hormones while having no influence on hormones that inhibit intestinal peristalsis. CONCLUSION: The study revealed that during sepsis, dexmedetomidine exhibited protective effects on barrier integrity, although concurrently it hindered intestinal motility, partly attributed to its modulation of pro-motility hormone secretion. These findings underscore the necessity of a comprehensive understanding of dexmedetomidine's impact on multiple facets of gastrointestinal physiology in sepsis management, offering potential implications for therapeutic strategies and patient care.


Subject(s)
Dexmedetomidine , Gastrointestinal Motility , Rats, Sprague-Dawley , Sepsis , Dexmedetomidine/pharmacology , Dexmedetomidine/therapeutic use , Animals , Sepsis/drug therapy , Gastrointestinal Motility/drug effects , Rats , Male , Adrenergic alpha-2 Receptor Agonists/pharmacology , Adrenergic alpha-2 Receptor Agonists/therapeutic use , Intestinal Mucosa/drug effects , Intestinal Mucosa/pathology , Disease Models, Animal , Permeability/drug effects
10.
Nat Commun ; 15(1): 4508, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38802455

ABSTRACT

Distributed energy systems encompass a diverse range of generation and storage solutions on the user side, where decentralized management schemes to maximize the overall social welfare are preferred considering their dispersed ownership. However, either security or privacy problems occur in recently proposed schemes. Here we report a decentralized framework leveraging the strengths of blockchain and parallelizable mathematical algorithms to overcome these potential drawbacks. The system owners bid cost functions and operating constraints through masked but coupled management subproblems, which are redistributed by the blockchain to be verifiably solved by competent peers. Such processes are iteratively executed as decisions and shadow prices are exchanged among participants, until an equilibrium is reached. The interactive framework ensures decentralized, privacy-preserving, and secure management of multiple energy sources, and reduces the total cost by 3.0 ~ 7.5% in the test system. Our results benefit the energy prosumers and promote a more active and competitive power grid.

11.
J Nephrol ; 37(4): 1063-1075, 2024 May.
Article in English | MEDLINE | ID: mdl-38594600

ABSTRACT

BACKGROUND: Nutcracker syndrome is a disease characterized by complex symptoms, making its diagnosis challenging and often delayed, often resulting in a painful experience for the patients. OBJECTIVE: This study aimed to investigate the pathogenesis of nutcracker syndrome through the perspective of hemodynamics by simulating blood flow with varying compression degrees of the left renal vein. METHODS: 3D patient-specific vascular models of the abdominal aorta, superior mesenteric artery and left renal vein were constructed based on CT images of patients suspected of having nutcracker syndrome. A hemodynamic simulation was then conducted using computational fluid dynamics to identify the correlation between alterations in hemodynamic parameters and varying degrees of compression. RESULTS: The study indicated the presence of an evident gradient in velocity distribution over the left renal vein with relatively high degrees of stenosis (α ≤ 50°), with maximum velocity in the central region of the stenosis. Additionally, when the compression degree of the left renal vein increases, the pressure distribution of the left renal vein presents an increasing number of gradient layers. Furthermore, the wall shear stress shows a correlation with the variation of blood flow velocity, i.e., the increase of wall shear stress correlates with the acceleration of the blood flow velocity. CONCLUSIONS: Using computational fluid dynamics as a non-invasive instrument to obtain the hemodynamic characteristics of nutcracker syndrome is feasible and could provide insights into the pathological mechanisms of the nutcracker syndrome supporting clinicians in diagnosis.


Subject(s)
Hemodynamics , Renal Nutcracker Syndrome , Renal Veins , Humans , Renal Nutcracker Syndrome/physiopathology , Renal Nutcracker Syndrome/diagnostic imaging , Renal Veins/physiopathology , Renal Veins/diagnostic imaging , Blood Flow Velocity , Aorta, Abdominal/physiopathology , Aorta, Abdominal/diagnostic imaging , Mesenteric Artery, Superior/physiopathology , Mesenteric Artery, Superior/diagnostic imaging , Models, Cardiovascular , Hydrodynamics , Male , Female , Adult , Patient-Specific Modeling , Stress, Mechanical , Imaging, Three-Dimensional , Computer Simulation
12.
Neurosurg Rev ; 47(1): 137, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38564039

ABSTRACT

Despite 2-staged stereotactic radiosurgery (2-SSRS) has been reported to provide patients with improved survival and limited toxicity, 2-SSRS for brainstem metastases (BSM) larger than 2 cm3 remains challenging. We tried to find out the effectiveness and safety of 2-SSRS plus bevacizumab therapy for BSMs over 2 cm3 and prognostic factors that related to the tumor local control. Patients that received 2-SSRS plus bevacizumab therapy from four gamma knife center were retrospectively studied from Jan 2014 to December 2023. Patients' domestic characteristics and the tumor features were evaluated before and after the treatment. Cox regression model was used to find out prognostic factors for tumor local control. 53 patients with 63 lesions received the therapy. The median peri-tumor edema volume greatly reduced at the end of therapy (P < 0.01), the median tumor volume dramatically reduced (P < 0.01) and patients' KPS score improved significantly (P < 0.05) 3 months after the therapy. Patients' median OS was 12.8 months. The tumor local control rate at 3, 6, and 12 months was 98.4%, 93.4%, and 85.2%. The incidence side effects were mainly oral and nasal hemorrhage (5.7%, 3/53), and radiation necrosis (13.2%, 7/53). Patients with primary lung adenocarcinoma, therapeutic dose over 12 Gy at second-stage SRS, primary peri-tumor edema volume less than 2.3 cm³, primary tumor volume less than 3.7 cm³ would enjoy longer tumor local control. These results suggested that 2-SSRS plus bevacizumab therapy was effective and safe for BSMs over 2 cm3. However, it is important for patients with BSM to receive early diagnosis and treatment to achieve good tumor local control.


Subject(s)
Brain Stem , Neoplasms , Humans , Bevacizumab/therapeutic use , Retrospective Studies , Edema
13.
Cerebellum ; 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38558026

ABSTRACT

Repetitive transcranial magnetic stimulation (rTMS), a noninvasive neuroregulatory technique used to treat neurodegenerative diseases, holds promise for spinocerebellar ataxia type 3 (SCA3) treatment, although its efficacy and mechanisms remain unclear. This study aims to observe the short-term impact of cerebellar rTMS on motor function in SCA3 patients and utilize resting-state functional magnetic resonance imaging (RS-fMRI) to assess potential therapeutic mechanisms. Twenty-two SCA3 patients were randomly assigned to receive actual rTMS (AC group, n = 11, three men and eight women; age 32-55 years) or sham rTMS (SH group, n = 11, three men and eight women; age 26-58 years). Both groups underwent cerebellar rTMS or sham rTMS daily for 15 days. The primary outcome measured was the ICARS scores and parameters for regional brain activity. Compared to baseline, ICARS scores decreased more significantly in the AC group than in the SH group after the 15-day intervention. Imaging indicators revealed increased Amplitude of Low Frequency Fluctuation (ALFF) values in the posterior cerebellar lobe and cerebellar tonsil following AC stimulation. This study suggests that rTMS enhances motor functions in SCA3 patients by modulating the excitability of specific brain regions and associated pathways, reinforcing the potential clinical utility of rTMS in SCA3 treatment. The Chinese Clinical Trial Registry identifier is ChiCTR1800020133.

14.
Article in English | MEDLINE | ID: mdl-38668737

ABSTRACT

As transient electronics continue to advance, the demand for new materials has given rise to the exploration of conducting polymer (CP)-based electronic materials. The big challenge lies in balancing conductivity while introducing controlled degradable properties into CP-based transient materials. In response to this, we present in this work a concept of using conducting polymers attached to an enzymatically biodegradable biopolymer to create transient polymer electronics materials. Specifically, poly(3-hexyl thiophene) (P3HT) is covalently grafted onto biopolymer gelatin, affording graft copolymer gelatin-graft-poly(3-hexyl thiophene) (termed Gel-g-P3HT). The thin films of Gel-g-P3HT that were produced by optimized processing solvent (THF/H2O cosolvent) showed enhanced π-π stacking domains of P3HT, resulting in semiconducting thin films with good electroactivity. Due to the presence of amide bonds in the gelatin backbone, Gel-g-P3HT underwent degradation over a period of 5 days, resulting in the formation of amphiphilic micellar nanoparticles that are biocompatible and nontoxic. The potential of these conductive and degradable graft copolymers was demonstrated in a pressure sensor. This research paves the way for developing biocompatible and enzymatically degradable polymer materials based on P3HT, enabling the next generation of transient polymer electronics for diverse applications, such as skin, implantable, and environmental electronics.

15.
J Chem Phys ; 160(15)2024 Apr 21.
Article in English | MEDLINE | ID: mdl-38624109

ABSTRACT

A diabatic potential energy matrix (DPEM) for the two lowest states of BeH2+ has been constructed using the combined-hyperbolic-inverse-power-representation (CHIPR) method. By imposing symmetry constraints on the coefficients of polynomials, the complete nuclear permutation inversion symmetry is correctly preserved in the CHIPR functional form. The symmetrized CHIPR functional form is then used in the diabatization by ansatz procedure. The ab initio energies are reproduced with satisfactory accuracy. In addition, the CHIPR-based DPEM also reproduces the local topology of a conical intersection. Future work will focus on a complete four-state diabatic representation with emphasis on the long-range interactions and spin-orbit couplings, which will enable accurate quantum scattering calculations for the Be+(2P) + H2 → BeH+(X1Σ+) + H(2S) reaction.

16.
Circulation ; 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38660786

ABSTRACT

BACKGROUND: Dysregulated metabolism of bioactive sphingolipids, including ceramides and sphingosine-1-phosphate, has been implicated in cardiovascular disease, although the specific species, disease contexts, and cellular roles are not completely understood. Sphingolipids are produced by the serine palmitoyltransferase enzyme, canonically composed of 2 subunits, SPTLC1 (serine palmitoyltransferase long chain base subunit 1) and SPTLC2 (serine palmitoyltransferase long chain base subunit 2). Noncanonical sphingolipids are produced by a more recently described subunit, SPTLC3 (serine palmitoyltransferase long chain base subunit 3). METHODS: The noncanonical (d16) and canonical (d18) sphingolipidome profiles in cardiac tissues of patients with end-stage ischemic cardiomyopathy and in mice with ischemic cardiomyopathy were analyzed by targeted lipidomics. Regulation of SPTLC3 by HIF1α under ischemic conditions was determined with chromatin immunoprecipitation. Transcriptomics, lipidomics, metabolomics, echocardiography, mitochondrial electron transport chain, mitochondrial membrane fluidity, and mitochondrial membrane potential were assessed in the cSPTLC3KO transgenic mice we generated. Furthermore, morphological and functional studies were performed on cSPTLC3KO mice subjected to permanent nonreperfused myocardial infarction. RESULTS: Herein, we report that SPTLC3 is induced in both human and mouse models of ischemic cardiomyopathy and leads to production of atypical sphingolipids bearing 16-carbon sphingoid bases, resulting in broad changes in cell sphingolipid composition. This induction is in part attributable to transcriptional regulation by HIF1α under ischemic conditions. Furthermore, cardiomyocyte-specific depletion of SPTLC3 in mice attenuates oxidative stress, fibrosis, and hypertrophy in chronic ischemia, and mice demonstrate improved cardiac function and increased survival along with increased ketone and glucose substrate metabolism utilization. Depletion of SPTLC3 mechanistically alters the membrane environment and subunit composition of mitochondrial complex I of the electron transport chain, decreasing its activity. CONCLUSIONS: Our findings suggest a novel essential role for SPTLC3 in electron transport chain function and a contribution to ischemic injury by regulating complex I activity.

17.
Front Microbiol ; 15: 1345231, 2024.
Article in English | MEDLINE | ID: mdl-38426066

ABSTRACT

Introduction: The artificial cultivation of morels has been a global research focus owing to production variability. Understanding the microbial ecology in cultivated soil is essential to increase morel yield and alleviate pathogen harm. Methods: A total of nine Morchella cultivation experiments in four soil field types, forest, paddy, greenhouse, and orchard in Shanghai city were performed to determine the potential ecological relationship between Morchella growth and soil microbial ecology. Results: Generally, significant variation was observed in the soil microbial diversity and composition between the different experimental field types. The niche width analysis indicated that the bacterial habitat niche breadth was significantly greater than the fungal community width, which was further confirmed by a null model that revealed that homogeneous selection could explain 46.26 and 53.64% of the variance in the bacterial and fungal assemblies, respectively. Moreover, the neutral community model revealed that stochastic processes dominate the bacterial community in forests and paddies and both the bacterial and fungal communities in orchard crops, whereas deterministic processes mostly govern the fungal community in forests and paddies and both the bacterial and the fungal communities in greenhouses. Furthermore, co-occurrence patterns were constructed, and the results demonstrated that the dynamics of the soil microbial community are related to fluctuations in soil physicochemical characteristics, especially soil potassium. Importantly, structural equation modeling further demonstrated that the experimental soil type significantly affects the potassium content of the soil, which can directly or indirectly promote Morchella yield by inhibiting soil fungal richness. Discussion: This was the first study to predict morel yield through soil potassium fertilizer and soil fungal community richness, which provides new insights into deciphering the importance of microbial ecology in morel agroecosystems.

18.
Cancer Cell Int ; 24(1): 91, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38429830

ABSTRACT

BACKGROUND: Circular RNAs (circRNAs) belong to a class of covalently closed single stranded RNAs that have been implicated in cancer progression. Former investigations showed that hsa-circ-0013561 is abnormally expressed in head and neck squamous cell carcinoma (HNSCC). Nevertheless, the role of hsa-circ-0013561 during the progress of HNSCC still unclear. METHODS: Present study applied FISH and qRT-PCR to examine hsa-circ-0013561 expression in HNSCC cells and tissue samples. Dual-luciferase reporter assay was employed to identify downstream targets of hsa-circ-0013561. Transwell migration, 5-ethynyl-2'-deoxyuridine incorporation, CCK8 and colony formation assays were utilized to test cell migration and proliferation. A mouse tumor xenograft model was utilized to determine the hsa-circ-0013561 roles in HNSCC progression and metastasis in vivo. RESULTS: We found that hsa-circ-0013561 was upregulated in HNSCC tissue samples. hsa-circ-0013561 downregulation inhibited HNSCC cell proliferation and migration to promote apoptosis and G1 cell cycle arrest. The dual-luciferase reporter assay revealed that miR-7-5p and PDK3 are hsa-circ-0013561 downstream targets. PDK3 overexpression or miR-7-5p suppression reversed the hsa-circ-0013561-induced silencing effects on HNSCC cell proliferation and migration. PDK3 overexpression reversed miR-7-5p-induced effects on HNSCC cell proliferation and migration. CONCLUSION: The findings suggest that hsa-circ-0013561 downregulation inhibits HNSCC metastasis and progression through PDK3 expression and miR-7-5p binding modulation.

19.
Dalton Trans ; 53(14): 6215-6223, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38483279

ABSTRACT

The synthesis of cyclic carbonates through cycloaddition reactions between epoxides and carbon dioxide (CO2) is an important industrial process. Metal-Organic Frameworks (MOFs) have functional and ordered pore structures, making them attractive catalysts for converting gas molecules into valuable products. One approach to enhance the catalytic activity of MOFs in CO2 cycloaddition reactions is to create open metal sites within MOFs. In this study, the amino-functionalized rare earth Gd-MOF (Gd-TPTC-NH2) and its ionic liquid composite catalysts (Gd-TPTC-NH-[BMIM]Br) were synthesized using 2'-amino-[1,1':4',1''-terphenyl]-3,3'',5,5''-tetracarboxylic acid (H4TPTC-NH2) as the ligand. The catalytic performance of these two catalysts was observed in the cycloaddition reaction of CO2 and epoxides. Under the optimized reaction conditions, Gd-TPTC-NH-[BMIM]Br can effectively catalyze the cycloaddition reaction of a variety of epoxide substrates with good to excellent yields of cyclic carbonate products. Comparatively, epichlorohydrin and epibromohydrin, which possess halogen substituents, promote higher yields of cyclic carbonates due to the electron-withdrawing nature of Cl and Br substituents. Additionally, the Gd-TPTC-NH-[BMIM]Br catalyst demonstrated good recyclability and reproducibility, maintaining its catalytic activity without any changes in its structure or properties after five reuse cycles.

20.
Cell Death Dis ; 15(3): 237, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38555280

ABSTRACT

End-stage nasopharyngeal carcinoma (NPC) has unsatisfactory survival. The limited benefit of chemotherapy and the scarcity of targeted drugs are major challenges in NPC. New approaches to treat late-stage NPC are urgently required. In this study, we explored whether the dual PI3K/mTOR inhibitor, PQR309, exerted a favorable antineoplastic effect and sensitized the response to gemcitabine in NPC. We observed that PI3K expression was positive and elevated in 14 NPC cell lines compared with that in normal nasopharygeal cell lines. Patients with NPC with higher PI3K levels displayed poorer prognosis. We subsequently showed that PQR309 alone effectively decreased the viability, invasiveness, and migratory capability of NPC cells and neoplasm development in mice xenograft models, and dose-dependently induced apoptosis. More importantly, PQR309 remarkably strengthened the anti-NPC function of gemcitabine both in vivo and in vitro. Mechanistically, PQR309 sensitized NPC to gemcitabine by increasing caspase pathway-dependent apoptosis, blocking GSK-3ß and STAT3/HSP60 signaling, and ablating epithelial-mesenchyme transition. Thus, targeting PI3K/mTOR using PQR309 might represent a treatment option to promote the response to gemcitabine in NPC, and provides a theoretical foundation for the study of targeted drugs combined with chemotherapy for NPC.


Subject(s)
Nasopharyngeal Neoplasms , Phosphatidylinositol 3-Kinases , STAT3 Transcription Factor , Humans , Animals , Mice , Nasopharyngeal Carcinoma/drug therapy , Nasopharyngeal Carcinoma/metabolism , Glycogen Synthase Kinase 3 beta/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Gemcitabine , Signal Transduction , TOR Serine-Threonine Kinases/metabolism , Protein Kinase Inhibitors/pharmacology , Phosphoinositide-3 Kinase Inhibitors/pharmacology , MTOR Inhibitors , Angiogenesis Inhibitors/pharmacology , Nasopharyngeal Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation , Apoptosis , Proto-Oncogene Proteins c-akt/metabolism
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