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1.
Dev Cell ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38569547

RESUMO

The ability of cells to perceive and respond to mechanical cues is essential for numerous biological activities. Emerging evidence indicates important contributions of organelles to cellular mechanosensitivity and mechanotransduction. However, whether and how the endoplasmic reticulum (ER) senses and reacts to mechanical forces remains elusive. To fill the knowledge gap, after developing a light-inducible ER-specific mechanostimulator (LIMER), we identify that mechanostimulation of ER elicits a transient, rapid efflux of Ca2+ from ER in monkey kidney COS-7 cells, which is dependent on the cation channels transient receptor potential cation channel, subfamily V, member 1 (TRPV1) and polycystin-2 (PKD2) in an additive manner. This ER Ca2+ release can be repeatedly stimulated and tuned by varying the intensity and duration of force application. Moreover, ER-specific mechanostimulation inhibits ER-to-Golgi trafficking. Sustained mechanostimuli increase the levels of binding-immunoglobulin protein (BiP) expression and phosphorylated eIF2α, two markers for ER stress. Our results provide direct evidence for ER mechanosensitivity and tight mechanoregulation of ER functions, placing ER as an important player on the intricate map of cellular mechanotransduction.

2.
Int J Mol Sci ; 25(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38612541

RESUMO

Glycerol-3-phosphate acyltransferase (GPAT) catalyzes the first step in triacylglycerol synthesis. Understanding its substrate recognition mechanism may help to design drugs to regulate the production of glycerol lipids in cells. In this work, we investigate how the native substrate, glycerol-3-phosphate (G3P), and palmitoyl-coenzyme A (CoA) bind to the human GPAT isoform GPAT4 via molecular dynamics simulations (MD). As no experimentally resolved GPAT4 structure is available, the AlphaFold model is employed to construct the GPAT4-substrate complex model. Using another isoform, GPAT1, we demonstrate that once the ligand binding is properly addressed, the AlphaFold complex model can deliver similar results to the experimentally resolved structure in MD simulations. Following the validated protocol of complex construction, we perform MD simulations using the GPAT4-substrate complex. Our simulations reveal that R427 is an important residue in recognizing G3P via a stable salt bridge, but its motion can bring the ligand to different binding hotspots on GPAT4. Such high flexibility can be attributed to the flexible region that exists only on GPAT4 and not on GPAT1. Our study reveals the substrate recognition mechanism of GPAT4 and hence paves the way towards designing GPAT4 inhibitors.


Assuntos
Glicerol , Glicerofosfatos , Simulação de Dinâmica Molecular , Humanos , Ligantes , Glicerol-3-Fosfato O-Aciltransferase , Isoformas de Proteínas , Fosfatos
3.
J Nanobiotechnology ; 22(1): 161, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589895

RESUMO

Antibiotic resistance has garnered significant attention due to the scarcity of new antibiotics in development. Protoporphyrin IX (PpIX)-mediated photodynamic therapy shows promise as a novel antibacterial strategy, serving as an alternative to antibiotics. However, the poor solubility of PpIX and its tendency to aggregate greatly hinder its photodynamic efficacy. In this study, we demonstrate that alkylated EDTA derivatives (aEDTA), particularly C14-EDTA, can enhance the solubility of PpIX by facilitating its dispersion in aqueous solutions. The combination of C14-EDTA and PpIX exhibits potent antibacterial activity against Staphylococcus aureus (S. aureus) when exposed to LED light irradiation. Furthermore, this combination effectively eradicates S. aureus biofilms, which are known to be strongly resistant to antibiotics, and demonstrates high therapeutic efficacy in an animal model of infected ulcers. Mechanistic studies reveal that C14-EDTA can disrupt PpIX crystallization, increase bacterial membrane permeability and sequester divalent cations, thereby improving the accumulation of PpIX in bacteria. This, in turn, enhances reactive oxygen species (ROS) production and the antibacterial photodynamic activity. Overall, this effective strategy holds great promise in combating antibiotic-resistant strains.


Assuntos
Fotoquimioterapia , Staphylococcus aureus , Animais , Protoporfirinas/farmacologia , Ácido Edético/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química
4.
Proc Natl Acad Sci U S A ; 121(14): e2217019121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38547062

RESUMO

Mitochondria constantly fuse and divide for mitochondrial inheritance and functions. Here, we identified a distinct type of naturally occurring fission, tail-autotomy fission, wherein a tail-like thin tubule protrudes from the mitochondrial body and disconnects, resembling autotomy. Next, utilizing an optogenetic mitochondria-specific mechanostimulator, we revealed that mechanical tensile force drives tail-autotomy fission. This force-induced fission involves DRP1/MFF and endoplasmic reticulum tubule wrapping. It redistributes mitochondrial DNA, producing mitochondrial fragments with or without mitochondrial DNA for different fates. Moreover, tensile force can decouple outer and inner mitochondrial membranes, pulling out matrix-excluded tubule segments. Subsequent tail-autotomy fission separates the matrix-excluded tubule segments into matrix-excluded mitochondrial-derived vesicles (MDVs) which recruit Parkin and LC3B, indicating the unique role of tail-autotomy fission in segregating only outer membrane components for mitophagy. Sustained force promotes fission and MDV biogenesis more effectively than transient one. Our results uncover a mechanistically and functionally distinct type of fission and unveil the role of tensile forces in modulating fission and MDV biogenesis for quality control, underscoring the heterogeneity of fission and mechanoregulation of mitochondrial dynamics.


Assuntos
Proteínas de Membrana , Dinâmica Mitocondrial , Proteínas de Membrana/genética , Proteínas Mitocondriais/genética , Mitocôndrias/genética , DNA Mitocondrial , Controle de Qualidade , Dinaminas/genética
5.
Front Neurosci ; 18: 1361832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529265

RESUMO

Traumatic Brain Injury (TBI) is a prevalent form of neurological damage that may induce varying degrees of cognitive dysfunction in patients, consequently impacting their quality of life and social functioning. This article provides a mini review of the epidemiology in Chinese TBI patients and etiology of cognitive impairment. It analyzes the risk factors of cognitive impairment, discusses current management strategies for cognitive dysfunction in Chinese TBI patients, and summarizes the strengths and limitations of primary testing tools for TBI-related cognitive functions. Furthermore, the article offers a prospective analysis of future challenges and opportunities. Its objective is to contribute as a reference for the prevention and management of cognitive dysfunction in Chinese TBI patients.

6.
Biochar ; 6(1): 21, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38463456

RESUMO

One strategy to reduce CO2 emissions from cement production is to reduce the amount of Portland cement produced by replacing it with supplementary cementitious materials (SCMs). Biochar is a potential SCM that is an eco-friendly and stable porous pyrolytic material. However, the effects of biochar addition on the performances of Portland cement composites are not fully understood. This meta-analysis investigated the impact of biochar addition on the 7- and 28-day compressive strength of Portland cement composites based on 606 paired observations. Biochar feedstock type, pyrolysis conditions, pre-treatments and modifications, biochar dosage, and curing type all influenced the compressive strength of Portland cement composites. Biochars obtained from plant-based feedstocks (except rice and hardwood) improved the 28-day compressive strength of Portland cement composites by 3-13%. Biochars produced at pyrolysis temperatures higher than 450 °C, with a heating rate of around 10 C min-1, increased the 28-day compressive strength more effectively. Furthermore, the addition of biochar with small particle sizes increased the compressive strength of Portland cement composites by 2-7% compared to those without biochar addition. Biochar dosage of < 2.5% of the binder weight enhanced both compressive strengths, and common curing methods maintained the effect of biochar addition. However, when mixing the cement, adding fine and coarse aggregates such as sand and gravel affects the concrete and mortar's compressive strength, diminishing the effect of biochar addition and making the biochar effect nonsignificant. We concluded that appropriate biochar addition could maintain or enhance the mechanical performance of Portland cement composites, and future research should explore the mechanisms of biochar effects on the performance of cement composites. Supplementary Information: The online version contains supplementary material available at 10.1007/s42773-024-00309-2.

7.
J Opt Soc Am A Opt Image Sci Vis ; 41(2): 157-164, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437328

RESUMO

Feature point matching is one of the fundamental tasks in binocular vision. It directly affects the accuracy and quality of 3D reconstruction. This study proposes a directional region-based feature point matching algorithm based on the SURF algorithm to improve the accuracy of feature point matching. First, same-name points are selected as the matching reference points in the left and right images. Then, the SURF algorithm is used to extract feature points and construct the SURF feature point descriptors. During the matching process, the location relationship between the query feature point and the reference point in the left image is directed to determine the corresponding matching region in the right image. Then, the matching is completed within this region based on Euclidean distance. Finally, the grid-based motion statistics algorithm is used to eliminate mismatches. Experimental results show that the proposed algorithm can substantially improve the matching accuracy and the number of valid matched points, particularly in the presence of a large amount of noise and interference. It also exhibits good robustness and stability.

8.
Small ; : e2311930, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433391

RESUMO

Human health and the environment face significant challenges of air pollution, which is predominantly caused by PM2.5 or PM10 particles. Existing control methods often require elevated energy consumption or bulky high-voltage electrical equipment. To overcome these limitations, a self-powered, convenient, and compact direct current high-voltage triboelectric nanogenerator based on triboelectrification and electrostatic breakdown effects is proposed. By optimizing the structure-design of the direct current triboelectric nanogenerator and corresponding output voltage, it can easily achieve an output voltage of over 3 kV with a high charge density of 320 µC m-2 . A power management circuit is designed to overcome the influence of third domain self-breakdown, optimize 92.5% amplitude of voltage shake, and raise 5% charge utilization ratio. With a device size as tiny as 2.25 cm3 , it can continuously drive carbon nanowires to generate negative ions that settle dust within 300 s. This compact, simple, efficient, and safe high-voltage direct current triboelectric nanogenerator represents a promising sustainable solution. It offers efficient dust mitigation, fostering cleaner environments, and enhancing overall health.

9.
Front Endocrinol (Lausanne) ; 15: 1326112, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38390209

RESUMO

Background: Gallbladder neuroendocrine neoplasms (GB-NENs) are a rare malignant disease, with most cases diagnosed at advanced stages, often resulting in poor prognosis. However, studies regarding the prognosis of this condition and its comparison with gallbladder adenocarcinomas (GB-ADCs) have yet to yield convincing conclusions. Methods: We extracted cases of GB-NENs and GB-ADCs from the Surveillance, Epidemiology, and End Results (SEER) database in the United States. Firstly, we corrected differences in clinical characteristics between the two groups using propensity score matching (PSM). Subsequently, we visualized and compared the survival outcomes of the two groups using the Kaplan-Meier method. Next, we employed the least absolute shrinkage and selection operator (LASSO) regression and Cox regression to identify prognostic factors for GB-NENs and constructed two nomograms for predicting prognosis. These nomograms were validated with an internal validation dataset from the SEER database and an external validation dataset from a hospital. Finally, we categorized patients into high-risk and low-risk groups based on their overall survival (OS) scores. Results: A total of 7,105 patients were enrolled in the study, comprising 287 GB-NENs patients and, 6,818 GB-ADCs patients. There were substantial differences in clinical characteristics between patients, and GB-NENs exhibited a significantly better prognosis. Even after balancing these differences using PSM, the superior prognosis of GB-NENs remained evident. Independent prognostic factors selected through LASSO and Cox regression were age, histology type, first primary malignancy, tumor size, and surgery. Two nomograms for prognosis were developed based on these factors, and their performance was verified from three perspectives: discrimination, calibration, and clinical applicability using training, internal validation, and external validation datasets, all of which exhibited excellent validation results. Using a cutoff value of 166.5 for the OS nomogram score, patient mortality risk can be identified effectively. Conclusion: Patients with GB-NENs have a better overall prognosis compared to those with GB-ADCs. Nomograms for GB-NENs prognosis have been effectively established and validated, making them a valuable tool for assessing the risk of mortality in clinical practice.


Assuntos
Adenocarcinoma , Neoplasias da Vesícula Biliar , Neoplasias Gastrointestinais , Tumores Neuroendócrinos , Humanos , Estados Unidos , Prognóstico , Tumores Neuroendócrinos/diagnóstico , Medição de Risco , Adenocarcinoma/diagnóstico , Neoplasias da Vesícula Biliar/diagnóstico
10.
Sci Rep ; 14(1): 4374, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388766

RESUMO

The damage to the endocrine pancreas among patients with diseases of the exocrine pancreas (DP) leads to reduced glycemic deterioration, ultimately resulting in diabetes of the exocrine pancreas (DEP). The present research aims to investigate the mechanism responsible for glycemic deterioration in DP patients, and to identify useful biomarkers, with the ultimate goal of enhancing clinical practice awareness. Gene expression profiles of patients with DP in this study were acquired from the Gene Expression Omnibus database. The original study defines DP patients to belong in one of three categories: non-diabetic (ND), impaired glucose tolerance (IGT) and DEP, which correspond to normoglycemia, early and late glycemic deterioration, respectively. After ensuring quality control, the discovery cohort included 8 ND, 20 IGT, and 12 DEP, while the validation cohort included 27 ND, 15 IGT, and 20 DEP. Gene set enrichment analysis (GSEA) employed differentially expressed genes (DEGs), while immunocyte infiltration was determined using single sample gene set enrichment analysis (ssGSEA). Additionally, correlation analysis was conducted to establish the link between clinical characteristics and immunocyte infiltration. The least absolute shrinkage and selection operator regression and random forest combined to identify biomarkers indicating glycemic deterioration in DP patients. These biomarkers were further validated through independent cohorts and animal experiments. With glycemic deterioration, biological processes in the pancreatic islets such as nutrient metabolism and complex immune responses are disrupted in DP patients. The expression of ACOT4, B2M, and ACKR2 was upregulated, whereas the expression of CACNA1F was downregulated. Immunocyte infiltration in the islet microenvironment showed a significant positive correlation with the age, body mass index (BMI), HbA1c and glycemia at the 2-h of patients. It was a crucial factor in glycemic deterioration. Additionally, B2M demonstrated a significant positive correlation with immunocyte infiltration and clinical features. Quantitative real-time PCR (qRT-PCR) and western blotting confirmed the upregulation in B2M. Immunofluorescent staining suggested the alteration of B2M was mainly in the alpha cells and beta cells. Overall, the study showed that gradually increased immunocyte infiltration was a significant contributor to glycemic deterioration in patients with DP, and it also highlighted B2M as a biomarker.


Assuntos
Experimentação Animal , Intolerância à Glucose , Pâncreas Exócrino , Animais , Humanos , Complexo Antígeno-Anticorpo , Biomarcadores , Western Blotting
11.
Chin Neurosurg J ; 10(1): 4, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273380

RESUMO

BACKGROUND: Despite its prevalence, there is ongoing debate regarding the optimal management strategy for chronic subdural hematoma (CSDH), reflecting the variability in clinical presentation and treatment outcomes. This ambidirectional, nationwide, multicenter registry study aims to assess the efficacy and safety of multimodality treatment approaches for CSDH in the Chinese population. METHODS/DESIGN: A multicenter cohort of CSDH patients from 59 participating hospitals in mainland China was enrolled in this study. The treatment modalities encompassed a range of options and baseline demographics, clinical characteristics, radiographic findings, and surgical techniques were documented. Clinical outcomes, including hematoma resolution, recurrence rates, neurological status, and complications, were assessed at regular intervals during treatment, 3 months, 6 months, 1 year, and 2 years follow-up. RESULT: Between March 2022 and August 2023, a comprehensive cohort comprising 2173 individuals who met the criterion was assembled across 59 participating clinical sites. Of those patients, 81.1% were male, exhibiting an average age of 70.12 ± 14.53 years. A historical record of trauma was documented in 48.0% of cases, while headache constituted the predominant clinical presentation in 58.1% of patients. The foremost surgical modality employed was the burr hole (61.3%), with conservative management accounting for 25.6% of cases. Notably, a favorable clinical prognosis was observed in 88.9% of CSDH patients at 3 months, and the recurrence rate was found to be 2.4%. CONCLUSION: This registry study provides critical insights into the multimodality treatment of CSDH in China, offering a foundation for advancing clinical practices, optimizing patient management, and ultimately, improving the quality of life for individuals suffering from this challenging neurosurgical condition. TRIAL REGISTRATION: ChiCTR2200057179.

12.
Nanoscale ; 16(4): 1673-1684, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38189461

RESUMO

Addressing the challenges of chemodynamic therapies (CDTs) relying on Fenton reactions in malignant tumors is an active research area. Here, we report a method to develop pH-responsive hybrid nanoparticles for enhanced chemodynamic tumor treatment. Reactive CaO2 nanoparticles (core) are isolated by biocompatible ZIF-8 doped with Fe2+ (shell), and then encapsulated by macrophage membranes (symbolized as CaO2@Fe-ZIF-8@macrophage membrane or CFZM), thus endowed with high stability under normal physiological conditions. Our design features active tumor-homing by the macrophage-membrane coating, tumor microenvironment (TME)-responsive cargo release, and self-supplied hydrogen peroxide for promotion of the Fenton reaction. We demonstrate the improved delivery/tumor cell uptake of CFZM, the efficient production of toxic ˙OH with self-supplied H2O2 in CFZM, and high-efficacy tumor ablation on BALB/c mice bearing CT26 tumor cells. This offers a translational strategy to develop active tumor-targeting and TME-responsive nanotherapeutics with enhanced CDT against malignant tumors.


Assuntos
Nanopartículas , Neoplasias , Animais , Camundongos , Peróxido de Hidrogênio , Citoplasma , Macrófagos , Camundongos Endogâmicos BALB C , Microambiente Tumoral , Linhagem Celular Tumoral
13.
BMC Genomics ; 25(1): 1, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166541

RESUMO

BACKGROUND: There has been a significant surge in the global prevalence of diabetes mellitus (DM), which increases the susceptibility of individuals to ovarian cancer (OC). However, the relationship between DM and OC remains largely unexplored. The objective of this study is to provide preliminary insights into the shared molecular regulatory mechanisms and potential biomarkers between DM and OC. METHODS: Multiple datasets from the GEO database were utilized for bioinformatics analysis. Single cell datasets from the GEO database were analysed. Subsequently, immune cell infiltration analysis was performed on mRNA expression data. The intersection of these datasets yielded a set of common genes associated with both OC and DM. Using these overlapping genes and Cytoscape, a protein‒protein interaction (PPI) network was constructed, and 10 core targets were selected. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were then conducted on these core targets. Additionally, advanced bioinformatics analyses were conducted to construct a TF-mRNA-miRNA coregulatory network based on identified core targets. Furthermore, immunohistochemistry staining (IHC) and real-time quantitative PCR (RT-qPCR) were employed for the validation of the expression and biological functions of core proteins, including HSPAA1, HSPA8, SOD1, and transcription factors SREBF2 and GTAT2, in ovarian tumors. RESULTS: The immune cell infiltration analysis based on mRNA expression data for both DM and OC, as well as analysis using single-cell datasets, reveals significant differences in mononuclear cell levels. By intersecting the single-cell datasets, a total of 119 targets related to mononuclear cells in both OC and DM were identified. PPI network analysis further identified 10 hub genesincludingHSP90AA1, HSPA8, SNRPD2, UBA52, SOD1, RPL13A, RPSA, ITGAM, PPP1CC, and PSMA5, as potential targets of OC and DM. Enrichment analysis indicated that these genes are primarily associated with neutrophil degranulation, GDP-dissociation inhibitor activity, and the IL-17 signaling pathway, suggesting their involvement in the regulation of the tumor microenvironment. Furthermore, the TF-gene and miRNA-gene regulatory networks were validated using NetworkAnalyst. The identified TFs included SREBF2, GATA2, and SRF, while the miRNAs included miR-320a, miR-378a-3p, and miR-26a-5p. Simultaneously, IHC and RT-qPCR reveal differential expression of core targets in ovarian tumors after the onset of diabetes. RT-qPCR further revealed that SREBF2 and GATA2 may influence the expression of core proteins, including HSP90AA1, HSPA8, and SOD1. CONCLUSION: This study revealed the shared gene interaction network between OC and DM and predicted the TFs and miRNAs associated with core genes in monocytes. Our research findings contribute to identifying potential biological mechanisms underlying the relationship between OC and DM.


Assuntos
Diabetes Mellitus , MicroRNAs , Neoplasias Ovarianas , Humanos , Feminino , Superóxido Dismutase-1 , MicroRNAs/genética , Neoplasias Ovarianas/genética , Biologia Computacional , RNA Mensageiro , Redes Reguladoras de Genes , Microambiente Tumoral/genética
15.
Angew Chem Int Ed Engl ; 63(11): e202318989, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38221223

RESUMO

As bulky pollutants in industrial and agricultural wastewater, nitrate and formaldehyde pose serious threats to the human health and ecosystem. Current purification technologies including chemical and bio-/photo-/electro-chemical methods, are generally high-cost, time-consuming, or energy-intensive. Here, we report a novel formaldehyde-nitrate battery by pairing anodic formaldehyde oxidation with cathodic nitrate reduction, which simultaneously enables wastewater purification, electricity generation, and the production of high-value-added ammonia and formate. As a result, the formaldehyde-nitrate battery remarkably exhibits an open-circuit voltage of 0.75 V, a peak power density of 3.38 mW cm-2 and the yield rates of 32.7 mg h-1 cm-2 for ammonia and 889.4 mg h-1 cm-2 for formate. In a large-scale formaldehyde-nitrate battery (25 cm2 ), 99.9 % of nitrate and 99.8 % of formaldehyde are removed from simulated industrial wastewater and the electricity of 2.03 W⋅h per day is generated. Moreover, the design of such a multi-functional battery is universally applicable to the coupling of NO3 - or NO2 - reduction with various aldehyde oxidization, paving a new avenue for wastewater purification and chemical manufacturing.

16.
Anal Chem ; 96(3): 1073-1083, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38206976

RESUMO

The spatial distribution of lipidomes in tissues is of great importance in studies of living processes, diseases, and therapies. Mass spectrometry imaging (MSI) has become a critical technique for spatial lipidomics. However, MSI of low-abundance or poorly ionizable lipids is still challenging because of the ion suppression from high-abundance lipids. Here, a metal-organic framework (MOF) Zr6O4(OH)4(1,3,5-Tris(4-carboxyphenyl) benzene)2(triflate)6(Zr6OTf-BTB) was prepared and used for selective on-tissue adsorption of phospholipids to reduce ion suppression from them to poorly ionizable lipids. The results show that Zr6OTf-BTB with strong Lewis acidic sites and a large specific surface area (647.9 m2·g-1) could selectively adsorb phospholipids under 1% FA-MeOH. Adsorption efficiencies of phospholipids are 88.4-144.9 times higher than those of other neutral lipids. Moreover, the adsorption capacity and the adsorption kinetic rate constant of the new material to phospholipids are higher than those of Zr6-BTB (242.72 vs 73.96 mg·g-1, 0.0442 vs 0.0220 g·mg-1·min-1). A Zr6OTf-BTB sheet was prepared by a lamination technique for on-tissue phospholipid adsorption from brain tissue. Then, the tissue section on the Zr6OTf-BTB sheet was directly imaged via ambient liquid extraction-MSI with 1% FA-MeOH as the sampling solvent. The results showed that phospholipids could be 100% removed directly on tissue, and the detection coverage of the Zr6OTf-BTB-enhanced MSI method to ceramides (Cers) and hexosylceramides (HexCers) was increased by 5-26 times compared with direct tissue MSI (26 vs 1 and 17 vs 3). The new method provides an efficient and convenient way to eliminate the ion suppression from phospholipids in MSI, largely improving the detection coverage of low-abundance and poorly ionizable lipids.


Assuntos
Estruturas Metalorgânicas , Espectrometria de Massas/métodos , Fosfolipídeos , Diagnóstico por Imagem , Encéfalo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
17.
Neurosurgery ; 94(3): 497-507, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37796000

RESUMO

BACKGROUND AND OBJECTIVES: The focus on evidence-based neurosurgery has led to a considerable amount of neurosurgical evidence based on randomized controlled trials (RCTs) being published. Nevertheless, there has been no systematic appraisal of China's contribution to RCTs. Information about the changes in characteristics of Chinese neurosurgical RCTs before and during the COVID-19 pandemic is limited. This study aims to perform a detailed examination and comprehensive analysis of the characteristics of Chinese neurosurgical RCTs and to examine the differences before and during the COVID-19 pandemic. METHODS: We conducted a comprehensive database search including PubMed, Web of Science, Embase, and Cochrane Library up to March 2023, with a criterion of inclusion based on an impact factor above 0. We subsequently examined the design and quality parameters of the included RCTs and assessed the differences before and during the COVID-19 pandemic (based on follow-up ending before or after January 2020). Moreover, we investigated potential factors that may affect the quality and developmental trends of neurosurgical RCTs in China. RESULTS: The main focus of the 91 neurosurgical RCTs was vascular disease (47.3%) and trauma (18.7%). Over half of the trials used Consolidated Standards of Reporting Trial diagrams (69.2%), and the majority compared nonsurgical treatments (63.7%). Larger trials tended to have better quality scores, but those with significant efficacy were less likely to have power calculations. Over time, there was an increase in the use of Consolidated Standards of Reporting Trial diagrams and well-specified outcomes. The COVID-19 pandemic may have hindered the completion of neurosurgical RCTs in China, but it has had little impact on the design and quality so far. CONCLUSION: Chinese neurosurgeons have made significant progress in advancing neurosurgical RCTs despite challenges. However, shortcomings in sample size and power calculation need attention. Improving the rigor, rationality, and completeness of neurosurgical RCT design is crucial.


Assuntos
COVID-19 , Neurocirurgia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Procedimentos Neurocirúrgicos , Projetos de Pesquisa , COVID-19/epidemiologia
18.
Talanta ; 270: 125564, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38159350

RESUMO

Localization of lipidomes and tracking their spatial changes in tissues by mass spectrometry imaging (MSI) plays an important role in unveiling the mechanisms of living processes, diseases and therapeutic treatments. However, it is always challenging to achieve direct MSI of poorly-ionizable lipids, such as glycolipids and glycerolipids, due to the strong ion suppression and isobaric peaks interference from high-abundance phosphatidylcholines (PCs) in tissues. Here we developed a photocatalytic degradation-based ambient liquid extraction MSI method to largely enhance the detection coverage of poorly-ionizable lipids by rapid online removal of PCs in MSI. Phospholipids were found to be selectively photodegraded on TiO2 surface in acidic conditions in the presence of water under UV irradiation, while other poorly-ionizable lipids remained. Sulfate ion could largely improve the degradation efficiencies. Anatase nanoparticles-embedded TiO2 monolith was in-situ synthesized in the capillary of ambient liquid extraction system, and rapid online photodegradation of PCs was achieved during MSI with efficiency >80 %, largely reducing ion suppression. The pathway analysis showed that PC was oxidatively degraded starting from hydroxylation of C=C bonds. With intense UV irradiation, PCs were completely degraded into small molecules<200 Da without interference on the detection of endogenous lipids. With the new MSI method, detection coverage to cerebrosides, ceramides and diglycerides was enhanced by 2-9 times comparing with traditional MSI. Clearer localizations were observed for poorly-ionizable lipids via the new method than traditional method. Thus, this work provided a complementary MSI method for traditional MSI to address the issues on direct imaging of poorly ionizable lipids in ambient conditions.


Assuntos
Diagnóstico por Imagem , Lipidômica , Espectrometria de Massas/métodos , Glicolipídeos , Ceramidas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
19.
J Chromatogr A ; 1714: 464580, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38154349

RESUMO

It is important to recycle the bovine blood discarded at slaughter and develop it into high value-added bovine serum products. Biomimetic affinity chromatography (BiAC) resins have been developed to specifically purify bovine serum immunoglobulin G (Bs-IgG). The BiAC strategy was used to screen the resins with the best purification effect on Bs-IgG. Four resins with specificity for Bs-IgG adsorption were selected from 90 BiAC resins. Finally, BiAC-A5-87 was selected and used to purify Bs-IgG based on the results of SDS-PAGE and BCA protein quantification analysis. The adsorption capacity and purity of BiAC-A5-87 were 32.79 ± 3.57 mg/mL and 85.9 ± 1.21 % for Bs-IgG, respectively. The total protein recovery rate of Bs-IgG purified by BiAC-A5-87 was 89.78±3.52 %. The resin of BiAC-A5-87 column was recycled in 40 breakthrough cycles, and its Bs-IgG adsorption efficiency decreased by less than 10 %. After soaking BiAC-A5-87 in 1.0 moL NaOH solution for 64 h, its adsorption capacity for Bs-IgG was almost the same as that before soaking. The development of waste bovine serum not only realizes the utilization of blood resources and produces high economic benefits but also reduces the pollution of the environment.


Assuntos
Biomimética , Imunoglobulina G , Imunoglobulina G/metabolismo , Cromatografia de Afinidade/métodos , Soro/metabolismo , Adsorção
20.
Angew Chem Int Ed Engl ; 63(8): e202318967, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38153676

RESUMO

Lithium-mediated electrochemical nitrogen reduction reaction (Li-NRR) completely eschews the competitive hydrogen evolution reaction (HER) occurred in aqueous system, whereas the continuous deposition of lithium readily blocks the active sites and further reduces the reaction kinetics. Herein, we propose an innovative in situ Li migration strategy to realize that Li substitutes Mn sites in λ-MnO2 instead of evolving into the dead Li. Comprehensive characterizations corroborate that the intercalation of Li+ at high voltage breaks the structural integrity of MnO6 octahedron and further triggers unique Jahn-Teller distortions, which promotes the spin state regulation of Mn sites to generate the ameliorative eg orbital configuration and accelerates N≡N bond cleavage via eg -σ and eg -π* interaction. To this end, the resulted cationic disordered LiMnO4 delivers the recorded highest NH3 yield rate of 220 µg h-1 cm-2 and a Faradaic efficiency (FE) 83.80 % in organic electrolyte.

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