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1.
J Chem Theory Comput ; 20(8): 3085-3095, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38568961

ABSTRACT

Ligand binding free energy simulations (LB-FES) that involve sampling of protein functional conformations have been longstanding challenges in research on molecular recognition. Particularly, modeling of the conformational transition pathway and design of the heuristic biasing mechanism are severe bottlenecks for the existing enhanced configurational sampling (ECS) methods. Inspired by the key role of hydration in regulating conformational dynamics of macromolecules, this report proposes a novel ECS approach that facilitates binding-associated structural dynamics by accelerated hydration transitions in combination with the λ-exchange of free energy perturbation (FEP). Two challenging protein-ligand binding processes involving large configurational transitions of the receptor are studied, with hydration transitions at binding sites accelerated by Hamiltonian-simulated annealing of the hydration layer. Without the need for pathway analysis or ad hoc barrier flattening potential, LB-FES were performed with FEP/λ-exchange molecular dynamics simulation at a minor overhead for annealing of the hydration layer. The LB-FES studies showed that the accelerated rehydration significantly enhances the collective conformational transitions of the receptor, and convergence of binding affinity calculations is obtained at a sweet-spot simulation time scale. Alchemical LB-FES with the proposed ECS strategy is free from the effort of trial and error for the setup and realizes efficient on-the-fly sampling for the collective functional response of the receptor and bound water and therefore presents a practical approach to high-throughput screening in drug discovery.


Subject(s)
Molecular Dynamics Simulation , Thermodynamics , Ligands , Protein Binding , Solvents/chemistry , Binding Sites , Water/chemistry , Protein Conformation , Proteins/chemistry
2.
Heliyon ; 10(8): e29681, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38665558

ABSTRACT

Objective: This study aims to investigate the effects of melatonin-induced upregulation of telomerase activity on mitochondrial metabolism and NLRP3 inflammasome activation in macrophages, with the ultimate goal of elucidating potential therapeutic implications for pneumonia treatment. Materials and methods: Macrophages were treated with melatonin to assess its impact on telomerase activity. Mitochondrial function was evaluated through the measurement of reactive oxygen species (ROS) levels and cellular energy production. NLRP3 inflammasome activation was assessed by examining the production of inflammatory cytokines, such as interleukin-1ß (IL-1ß). The expression levels of key proteins involved in mitochondrial metabolism and NLRP3 inflammasome signaling were also analyzed. Results: Our findings demonstrated that melatonin treatment significantly upregulated telomerase activity in macrophages. This was associated with a reduction in ROS levels and enhanced cellular energy production, indicating improved mitochondrial function. Moreover, melatonin treatment suppressed NLRP3 inflammasome activation, resulting in reduced secretion of IL-1ß. The expression levels of proteins involved in mitochondrial metabolism and NLRP3 inflammasome signaling were modulated by melatonin. Conclusion: These results suggest that melatonin-induced upregulation of telomerase activity can interfere with mitochondrial metabolism and inhibit NLRP3 inflammasome activation in macrophages. This indicates a potential therapeutic role for melatonin in the treatment of pneumonia. Understanding the molecular mechanisms underlying these effects may lead to the development of novel therapeutic strategies targeting mitochondria and NLRP3 inflammasome activation for the management of pneumonia. Further investigations are warranted to fully uncover the therapeutic potential of melatonin and its implications for pneumonia treatment.

3.
BMC Health Serv Res ; 24(1): 489, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38641797

ABSTRACT

OBJECTIVE: To understand the awareness and practice of diabetic kidney disease (DKD) or nephropathy screening among community-based patients with type 2 diabetes in six provinces and cities in China, and to analyse the related factors affecting screening practices. METHODS: From December 2021 to March 2022, a cross-sectional survey was conducted using a structured questionnaire in 6230 patients with type 2 diabetes aged 18 years and older. The content of the questionnaire includes three parts: the general situation of diabetic patients (gender, age, ethnicity, marriage, education, occupation, etc.), DKD screening practices, and the evaluation of DKD screening services. RESULTS: 89.70% of the patients had their fasting blood glucose measured every six months, 21.12% of the patients had their glycosylated hemoglobin measured every six months, and only 13.11% and 9.34% of the patients had a urine protein-creatinine ratio test and estimated glomerular filtration rate test every 12 months. The proportions of glycosylated hemoglobin, urine protein-creatinine ratio, and estimated glomerular filtration rate were relatively high in young, northern, highly educated, and long-duration type 2 diabetic patients. CONCLUSION: The results of this survey found that the proportion of urine protein-creatinine ratio testing, estimated glomerular filtration rate testing, and glycosylated hemoglobin testing in Chinese patients with type 2 diabetes was very low. Patients with type 2 diabetes in rural areas, southern areas, with low education level, and short course of disease have lower detection rates for DKD, and hence lower rates of prevention and treatment.


Subject(s)
Diabetes Mellitus, Type 2 , Diabetic Nephropathies , Humans , Diabetic Nephropathies/diagnosis , Diabetic Nephropathies/epidemiology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/epidemiology , Cross-Sectional Studies , Glycated Hemoglobin , Creatinine/urine , China/epidemiology
4.
Biomed Pharmacother ; 174: 116625, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38643543

ABSTRACT

AIMS: The purpose of this study was to explore the impacts of salidroside on vascular regeneration, vascular structural changes and long-term neurological recuperation following cerebral ischemia and its possible mechanism. MAIN METHODS: From Day 1 to Day 28, young male mice with middle cerebral artery blockage received daily doses of salidroside and measured neurological deficits. On the 7th day after stroke, the volume of cerebral infarction was determined using TTC and HE staining. Microvascular density, astrocyte coverage, angiogenesis and the expression of the Shh signaling pathway were detected by IF, qRTPCR and WB at 7, 14 and 28 days after stroke. Changes in blood flow, blood vessel density and diameter from stroke to 28 days were measured by the LSCI and TPMI. KEY FINDINGS: Compared with the dMACO group, the salidroside treatment group significantly promoted the recovery of neurological function. Salidroside was found to enhance cerebral blood flow perfusion and reduce the infarct on the 7th day after stroke. From the 7th to the 28th day after stroke, salidroside treatment boosted the expression of CD31, CD31+/BrdU+, and GFAP in the cortex around the infarction site. On the 14th day after stroke, salidroside significantly enhanced the width and density of blood vessels. Salidroside increased the expression of histones and genes in the Shh signaling pathway during treatment, and this effect was weakened by the Shh inhibitor Cyclopamine. SIGNIFICANCE: Salidroside can restore nerve function, improve cerebral blood flow, reduce cerebral infarction volume, increase microvessel density and promote angiogenesis via the Shh signaling pathway.

5.
Phytomedicine ; 129: 155597, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38643713

ABSTRACT

BACKGROUND: Sepsis-induced cardiac dysfunction (SICD) is a serious complication of sepsis that is associated with increased mortality. Ferroptosis has been reported in the SICD. TaoHe ChengQi decoction (THCQD), a classical traditional Chinese medicinal formula, has multiple beneficial pharmacological effects. The potential effects of THCQD on the SICD remain unknown. PURPOSE: To investigate the effect of THCQD on SICD and explore whether this effect is related to the regulation of myocardial ferroptosis through nuclear factor erythroid 2-related factor 2 (Nrf2) activation. METHODS: We induced sepsis in a mouse model using cecal ligation and puncture (CLP) and administered THCQD (2 and 4 g/kg) and dexamethasone (40 mg/kg). Mice mortality was recorded and survival curves were plotted. Echocardiography, hematoxylin and eosin staining, and analysis of serum myocardial injury markers and inflammatory factors were used to evaluate cardiac pathology. Myocardial ferroptosis was detected by quantifying specific biomarker content and protein levels. Through HPLC-Q-Exactive-MS analysis, we identified the components of the THCQD. Network pharmacology analysis and Cellular Thermal Shift Assay (CETSA) were utilized to predict the targets of THCQD for treating SICD. We detected the expression of Nrf2 using Western blotting or immunofluorescence. An RSL3-induced ferroptosis model was established using neonatal rat cardiomyocytes (NRCMs) to further explore the pharmacological mechanism of THCQD. In addition to measuring cell viability, we observed changes in NRCM mitochondria using electron microscopy and JC-1 staining. NRF2 inhibitor ML385 and Nrf2 knockout mice were used to validate whether THCQD exerted protective effects against SICD through Nrf2-mediated ferroptosis signaling. RESULTS: THCQD reduced mortality in septic mice, protected against CLP-induced myocardial injury, decreased systemic inflammatory response, and prevented myocardial ferroptosis. Network pharmacology analysis and CETSA experiments predicted that THCQD may protect against SICD by activating the Nrf2 signaling pathway. Western blotting and immunofluorescence showed that THCQD activated Nrf2 in cardiac tissue. THCQDs consistently mitigated RSL3-induced ferroptosis in NRCM, which is related to Nrf2. Furthermore, the pharmacological inhibition of Nrf2 and genetic Nrf2 knockout partially reversed the protective effects of THCQD on SICD and ferroptosis. CONCLUSION: The effect of THCQD on SICD was achieved by activating Nrf2 and its downstream pathways.

6.
Ecotoxicol Environ Saf ; 276: 116332, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38626608

ABSTRACT

According to the International Agency for Research on Cancer (IARC), aflatoxin B1 (AFB1) has been recognized as a major contaminant in food and animal feed and which is a common mycotoxin with high toxicity. Previous research has found that AFB1 inhibited zebrafish muscle development. However, the potential mechanism of AFB1 on fish muscle development is unknown, so it is necessary to conduct further investigation. In the present research, the primary myoblast of grass carp was used as a model, we treated myoblasts with AFB1 for 24 h. Our results found that 5 µM AFB1 significantly inhibited cell proliferation and migration (P < 0.05), and 10 µM AFB1 promoted lactate dehydrogenase (LDH) release (P < 0.05). Reactive oxygen species (ROS), protein carbonyl (PC) and malondialdehyde (MDA) levels were increased in 15, 5 and 10 µM AFB1 (P < 0.05), respectively. Catalase (CAT), glutathione peroxidase (GPx) and total superoxide dismutase (T-SOD) activities were decreased in 10, 10 and 15 µM AFB1 (P < 0.05), respectively. Furthermore, 15 µM AFB1 induced oxidative damage by Nrf2 pathway, also induced apoptosis in primary myoblast of grass carp. Meanwhile, 15 µM AFB1 decreased MyoD gene and protein expression (P < 0.05). Importantly, 15 µM AFB1 decreased the protein expression of collagen Ⅰ and fibronectin (P < 0.05), and increased the protein levels of urokinase plasminogen activator (uPA), matrix metalloproteinase 9 (MMP-9), matrix metalloproteinase 2 (MMP-2), and p38 mitogen-activated protein kinase (p38MAPK) (P < 0.05). As a result, our findings suggested that AFB1 damaged the cell morphology, induced oxidative damage and apoptosis, degraded ECM components, in turn inhibiting myoblast development by activating the p38MAPK/urokinase-type plasminogen activator (uPA)/matrix metalloproteinase (MMPs)/extracellular matrix (ECM) signaling pathway.

7.
Am J Emerg Med ; 80: 185-193, 2024 Apr 06.
Article in English | MEDLINE | ID: mdl-38626653

ABSTRACT

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) remains a significant cause of mortality and morbidity worldwide. Extracorporeal cardiopulmonary resuscitation (ECPR) is a potential intervention for OHCA, but its effectiveness compared to conventional cardiopulmonary resuscitation (CCPR) needs further evaluation. METHOD: We systematically searched PubMed, Embase, the Cochrane Library, Web of Science, and ClinicalTrials.gov for relevant studies from January 2010 to March 2023. Pooled meta-analysis was performed to investigate any potential association between ECPR and improved survival and neurological outcomes. RESULTS: This systematic review and meta-analysis included two randomized controlled trials enrolling 162 participants and 10 observational cohort studies enrolling 4507 participants. The pooled meta-analysis demonstrated that compared to CCRP, ECPR did not improve survival and neurological outcomes at 180 days following OHCA (RR: 3.39, 95% CI: 0.79 to 14.64; RR: 2.35, 95% CI: 0.97 to 5.67). While a beneficial effect of ECPR was obtained regarding 30-day survival and neurological outcomes. Furthermore, ECPR was associated with a higher risk of bleeding complications. Subgroup analysis showed that ECPR was prominently beneficial when exclusively initiated in the emergency department. Additional post-resuscitation treatments did not significantly impact the efficacy of ECPR on 180-day survival with favorable neurological outcomes. CONCLUSIONS: There is no high-quality evidence supporting the superiority of ECPR over CCPR in terms of survival and neurological outcomes in OHCA patients. However, due to the potential for bias, heterogeneity among studies, and inconsistency in practice, the non-significant results do not preclude the potential benefits of ECPR. Further high-quality research is warranted to optimize ECPR practice and provide more generalizable evidence. Clinical trial registration PROSPERO, https://www.crd.york.ac.uk/prospero/, registry number: CRD42023402211.

8.
Chemistry ; : e202401079, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38563628

ABSTRACT

The interactions between ether naphthotube and a series of dication guests in organic solution were investigated. It was found that ether naphthotube formed stable host-guest complexes selectively with these guests in a 1 : 1 stoichiometric ratio with association constants ranging from 102 to 106 M-1, which were confirmed by 1H-NMR spectra and ITC experiments. The host-guest interactions are driven by enthalpy change as the entropic factors are unfavorable. Positive correlations between ΔH and ΔS have been observed in the host-guest complexes. Furthermore, the para-substitution of the guests can significantly affect the binding affinities through a combination of field/inductive and resonance effects by following a linear free energy relationship. Based on the host-guest complexes composed of ether naphthotube and organic cations, two interlocked [2]rotaxanes were prepared by cationization reaction and Huisgen cycloaddition between the cations and the stopper components. The ether naphthotube-based host-guest complexes are useful for creating sophisticated interlocked molecules.

9.
J Agric Food Chem ; 72(15): 8460-8475, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38564364

ABSTRACT

Liver injury and progressive liver failure are severe life-threatening complications in sepsis, further worsening the disease and leading to death. Macrophages and their mediated inflammatory cytokine storm are critical regulators in the occurrence and progression of liver injury in sepsis, for which effective treatments are still lacking. l-Ascorbic acid 6-palmitate (L-AP), a food additive, can inhibit neuroinflammation by modulating the phenotype of the microglia, but its pharmacological action in septic liver damage has not been fully explored. We aimed to investigate L-AP's antisepticemia action and the possible pharmacological mechanisms in attenuating septic liver damage by modulating macrophage function. We observed that L-AP treatment significantly increased survival in cecal ligation and puncture-induced WT mice and attenuated hepatic inflammatory injury, including the histopathology of the liver tissues, hepatocyte apoptosis, and the liver enzyme levels in plasma, which were comparable to NLRP3-deficiency in septic mice. L-AP supplementation significantly attenuated the excessive inflammatory response in hepatic tissues of septic mice in vivo and in cultured macrophages challenged by both LPS and ATP in vitro, by reducing the levels of NLRP3, pro-IL-1ß, and pro-IL-18 mRNA expression, as well as the levels of proteins for p-I-κB-α, p-NF-κB-p65, NLRP3, cleaved-caspase-1, IL-1ß, and IL-18. Additionally, it impaired the inflammasome ASC spot activation and reduced the inflammatory factor contents, including IL-1ß and IL-18 in plasma/cultured superannuants. It also prevented the infiltration/migration of macrophages and their M1-like inflammatory polarization while improving their M2-like polarization. Overall, our findings revealed that L-AP protected against sepsis by reducing macrophage activation and inflammatory cytokine production by suppressing their activation in NF-κB and NLRP3 inflammasome signal pathways in septic liver.


Subject(s)
Inflammasomes , Sepsis , Mice , Animals , Inflammasomes/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , NF-kappa B/genetics , NF-kappa B/metabolism , Caspase 1/genetics , Caspase 1/metabolism , Interleukin-18 , Macrophage Activation , Signal Transduction , Liver/metabolism , Ascorbic Acid , Sepsis/complications , Sepsis/drug therapy , Lipopolysaccharides/pharmacology
10.
Int J Gen Med ; 17: 1213-1220, 2024.
Article in English | MEDLINE | ID: mdl-38562211

ABSTRACT

Background: Epidermal growth factor (EGF) is a potent pro-angiogenic molecule promoting the angiogenic phenotype of ankylosing spondylitis (AS). Studies demonstrated that EGF rs3756261 polymorphism was associated with the risk of inflammatory diseases, but not including AS. Methods: To investigate the association between EGF rs3756261 polymorphism and the risk of AS, we genotyped the EGF rs3756261 polymorphism in 208 patients with AS and 412 controls in a Chinese Han population using a custom-by-design 48-Plex SNP scanTM Kit. The serum EGF levels were measured using an enzyme-linked immunosorbent assay in 208 AS patients and 412 controls. Results: Our data indicated that EGF rs3756261 polymorphism was associated with an increased risk of AS in the Chinese Han population. Stratified analyses indicated that the EGF rs3756261 polymorphism elevated the risk of AS among the males, smokers, drinkers and those aged <30 years. In addition, the EGF rs3756261 polymorphism was related to increased CRP and HLA-B27 levels in AS patients. Next, we found that the average serum levels of EGF were significantly higher in AS patients compared with controls. Meanwhile, EGF serum levels were significantly higher in AG genotype carriers when compared with AA genotype carriers in AS patients. Conclusion: In conclusion, this study indicated that EGF rs3756261 polymorphism was associated with the risk of AS and EGF serum levels in a Chinese Han population.

12.
Front Microbiol ; 15: 1366021, 2024.
Article in English | MEDLINE | ID: mdl-38577687

ABSTRACT

4-Hydroxy-2,5-dimethyl-3 (2H)-furanone (HDMF) is widely used in the food industry as a spice and flavoring agent with high market demand. In this study, fructose-1,6-bisphosphate aldolase (FBA) and triose phosphate isomerase (TPI) were overexpressed in Zygosaccharomyces rouxii in the form of single and double genes, respectively, via electroporation. High-yield HDMF-engineered yeast strains were constructed by combining the analysis of gene expression levels obtained by real-time fluorescence quantitative PCR technology and HDMF production measured by HPLC. The results showed that there was a significant positive correlation between the production of HDMF and the expression levels of the FBA and TPI genes in yeast; the expression levels of the FBA and TPI genes were also positively correlated (p < 0.05). Compared with the wild type (WT), the engineered strains F10-D, T17-D, and TF15-A showed marked increases in HDMF production and FBA and TPI gene expression (p < 0.05) and exhibited great genetic stability with no obvious differences in biomass or colony morphology. In addition, the exogenous addition of d-fructose promoted the growth of Z. rouxii. Among the engineered strains, when fermented in YPD media supplemented with d-fructose for 5 days, TF15-A (overexpressing the FBA and TPI genes) generated the highest HDMF production of 13.39 mg/L, which is 1.91 times greater than that of the wild-type strain. The results above indicated that FBA and TPI, which are key enzymes involved in the process of HDMF biosynthesis by Z. rouxii, positively regulate the synthesis of HDMF at the transcriptional level. d-fructose can be used as a precursor for the biosynthesis of HDMF by engineered yeast in industrial production.

13.
Expert Opin Drug Saf ; 23(4): 497-511, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38556702

ABSTRACT

OBJECTIVES: To investigate the risk of hemorrhage associated with Immune Checkpoint Inhibitors (ICIs) and characterize its clinical features. METHODS: We systematically reviewed randomized clinical trials (RCTs) of hemorrhage related to ICIs and calculated odds ratios (ORs) with 95% confidence intervals (CIs). Pharmacovigilance studies were conducted by collecting ICIs-related hemorrhage cases from the FAERS database and assessing disproportionalities by reporting odds ratios (RORs) and information components (ICs). RESULTS: A total of 79 RCTs involving 45,100 patients were finally included in the systematic review, with four published RCTs (n = 1965) and 75 unpublished RCTs (n = 43135). The primary analysis showed no significant difference in ICIs compared to the control group (OR 1.18 [95% CI 1.00-1.38], p = 0.05). In subgroup analyses, anti-PD-L1 combined with anti-CTLA-4 increased the risk of hemorrhage (OR 1.95, p = 0.03), and anti-CTLA-4 increased the risk of hemorrhage in the gastrointestinal system (OR 2.23, p = 0.04). 3555 cases of hemorrhage from the FAERS database were included in the disproportionate analysis, and the result suggested that ICIs increased the risk of hemorrhage (IC025 = 0.23). CONCLUSION: Our study suggests that ICIs increase the risk of hemorrhage, and in particular, anti-CTLA-4 significantly increases the risk of hemorrhage in the gastrointestinal system.


Subject(s)
Immune Checkpoint Inhibitors , Pharmacovigilance , Humans , Databases, Factual , CTLA-4 Antigen , Hemorrhage
14.
ACR Open Rheumatol ; 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38563441

ABSTRACT

OBJECTIVE: Black groups have increased prevalence and accelerated pathogenicity of systemic lupus erythematosus (SLE) compared to other ethnic/racial groups. The microbiome and systemic microbial translocation are considered contributing factors to SLE disease pathogenesis. However, racial differences in the plasma microbiome and microbial translocation in lupus remain unknown. METHODS: In the current study, we investigated plasma levels of microbial translocation (lipopolysaccharide [LPS] and zonulin) and the plasma microbiome using microbial 16S RNA sequencing of Black and White patients with SLE and Black and White healthy controls. RESULTS: Plasma microbial translocation was increased in Black patients versus in White patients and in patients with SLE versus healthy controls regardless of race. Compared to sex, age, and disease status, race had the strongest association with plasma microbiome differences. Black groups (Black controls and Black patients) had lower α-diversity than White groups (White controls and White patients) and more distinct ß-diversity. Black and White patients demonstrated differences in plasma bacterial presence, including Staphylococcus and Burkholderia. Compared to White patients, Black patients had higher SLE Disease Activity Index (SLEDAI) scores and urinary protein levels as well as a trend for increased anti-double-stranded DNA (dsDNA) antibody levels consistent with the known increased severity of lupus in Black patients overall. Certain plasma bacteria at the genus level were identified that were associated with the SLEDAI score, urinary protein, and anti-dsDNA antibody levels. CONCLUSION: This study reveals racial differences in both quality and quantity of plasma microbial translocation and identified specific plasma microbiome differences associated with SLE disease pathogenesis. Thus, this study may provide new insights into future potential microbiome therapies on SLE pathogenesis.

15.
Pharmacology ; 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38657589

ABSTRACT

BACKGROUND: Acetaminophen is commonly used as an antipyretic and analgesic agent. Excessive APAP can induce liver toxicity, known as APAP induced liver injury (ALI). The metabolism and pathogenesis of APAP have been extensively studied in recent years, and many cellular processes such as autophagy, mitochondrial oxidative stress, mitochondrial dysfunction and liver regeneration have been identified to be involved in the pathogenesis of ALI. Caveolin-1 (CAV-1) as a scaffold protein has also been shown to be involved in the development of various diseases, especially liver disease and tumorigenesis. The role of CAV-1 in the development of liver disease and the association between them remains a challenging and uncharted territory. SUMMARY: In this review, we briefly explore the potential therapeutic effects of CAV-1 on APAP induced ALI through autophagy, oxidative stress, and lipid metabolism. Further research to better understand the mechanisms by which CAV-1 regulates liver injury will not only enhance our understanding of this important cellular process, but also help develop new therapies for human disease by targeting CAV-1 targets. KEY MESSAGES:  This review briefly summarizes the potential protective mechanisms of CAV-1 against liver injury caused by APAP.

16.
Angew Chem Int Ed Engl ; : e202405971, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38661248

ABSTRACT

Aqueous soluble and stable Cu(I) molecular catalysts featuring a catenane ligand composed of two dicationic, mutually repelling but mechanically interlocked macrocycles are reported. The ligand interlocking not only fine-tunes the coordination sphere and kinetically stabilizes the Cu(I) against air oxidation and disproportionation, but also buries the hydrophobic portions of the ligands and prevents their dissociation which are necessary for their good water solubility and a sustained activity. These catenane Cu(I) complexes can catalyze the oxidative C-C coupling of indoles and tetrahydroisoquinolines in water, using H2O2 as a green oxidant with a good substrate scope. The successful use of catenane ligands in exploiting aqueous Cu(I) catalysis thus highlights the many unexplored potential of mechanical bond as a design element for exploring transition metal catalysis under challenging conditions.

17.
Adv Mater ; : e2314274, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38647521

ABSTRACT

A gate stack that facilitates a high-quality interface and tight electrostatic control is crucial for realizing high-performance and low-power field-effect transistors (FETs). However, when constructing conventional metal-oxide-semiconductor structures with two-dimensional (2D) transition metal dichalcogenide channels, achieving these requirements becomes challenging due to inherent difficulties in obtaining high-quality gate dielectrics through native oxidation or film deposition. Here, we report a gate-dielectric-less device architecture of van der Waals Schottky gated metal-semiconductor FETs (vdW-SG MESFETs) using a molybdenum disulfide (MoS2) channel and surface-oxidized metal gates such as nickel and copper. Benefiting from the strong SG coupling, our MESFETs operate at remarkably low gate voltages, <0.5 V. Notably, they also exhibit Boltzmann-limited switching behavior featured by a subthreshold swing of ∼60 mV/dec and negligible hysteresis. These ideal FET characteristics are attributed to the formation of a Fermi-level (EF) pinning-free gate stack at the Schottky-Mott limit. Furthermore, we experimentally and theoretically confirm that EF depinning can be achieved by suppressing both metal-induced and disorder-induced gap states at the interface between the monolithic-oxide-gapped metal gate and the MoS2 channel. This work paves a new route for designing high-performance and energy-efficient 2D electronics. This article is protected by copyright. All rights reserved.

18.
Med Phys ; 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38648676

ABSTRACT

BACKGROUND: Liver lesions mainly occur inside the liver parenchyma, which are difficult to locate and have complicated relationships with essential vessels. Thus, preoperative planning is crucial for the resection of liver lesions. Accurate segmentation of the hepatic and portal veins (PVs) on computed tomography (CT) images is of great importance for preoperative planning. However, manually labeling the mask of vessels is laborious and time-consuming, and the labeling results of different clinicians are prone to inconsistencies. Hence, developing an automatic segmentation algorithm for hepatic and PVs on CT images has attracted the attention of researchers. Unfortunately, existing deep learning based automatic segmentation methods are prone to misclassifying peripheral vessels into wrong categories. PURPOSE: This study aims to provide a fully automatic and robust semantic segmentation algorithm for hepatic and PVs, guiding subsequent preoperative planning. In addition, to address the deficiency of the public dataset for hepatic and PV segmentation, we revise the annotations of the Medical Segmentation Decathlon (MSD) hepatic vessel segmentation dataset and add the masks of the hepatic veins (HVs) and PVs. METHODS: We proposed a structure with a dual-stream encoder combining convolution and Transformer block, named Dual-stream Hepatic Portal Vein segmentation Network, to extract local features and long-distance spatial information, thereby extracting anatomical information of hepatic and portal vein, avoiding misdivisions of adjacent peripheral vessels. Besides, a multi-scale feature fusion block based on dilated convolution is proposed to extract multi-scale features on expanded perception fields for local features, and a multi-level fusing attention module is introduced for efficient context information extraction. Paired t-test is conducted to evaluate the significant difference in dice between the proposed methods and the comparing methods. RESULTS: Two datasets are constructed from the original MSD dataset. For each dataset, 50 cases are randomly selected for model evaluation in the scheme of 5-fold cross-validation. The results show that our method outperforms the state-of-the-art Convolutional Neural Network-based and transformer-based methods. Specifically, for the first dataset, our model reaches 0.815, 0.830, and 0.807 at overall dice, precision, and sensitivity. The dice of the hepatic and PVs are 0.835 and 0.796, which also exceed the numeric result of the comparing methods. Almost all the p-values of paired t-tests on the proposed approach and comparing approaches are smaller than 0.05. On the second dataset, the proposed algorithm achieves 0.749, 0.762, 0.726, 0.835, and 0.796 for overall dice, precision, sensitivity, dice for HV, and dice for PV, among which the first four numeric results exceed comparing methods. CONCLUSIONS: The proposed method is effective in solving the problem of misclassifying interlaced peripheral veins for the HV and PV segmentation task and outperforming the comparing methods on the relabeled dataset.

19.
MethodsX ; 12: 102698, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38650998

ABSTRACT

BACKGROUND: Up to 20% of people with HIV (PWH) fail to recover their CD4+ T cell counts to levels similar to healthy controls after suppressive antiretroviral therapy (ART). Immune non-responders (INRs) are PWH on suppressive ART with CD4+ T cell counts lower than 350 cells/mL, whereas their CD8+ T cell counts are higher than healthy controls. We are the first group to report that increased anti-CD4 autoantibody IgGs in INRs are responsible for blunted CD4+ T cell reconstitution in PWH with ART and viral suppression through anti-CD4 IgG-induced antibody-mediated cytotoxicity (ADCC) against CD4+ T cells in vitro. Notably, anti-CD4 IgG-mediated poor CD4+ T cell recovery from suppressive ART is the only mechanism targeting CD4+ T cells, specifically. RESULTS: We provide a detailed one-by-one step protocol from antigen-specific antibody isolation using plasma samples, to ADCC assay. CONCLUSIONS: To promote reproducible research, a detailed protocol for isolating anti-CD4 IgG autoantibodies from plasma samples of PWH and evaluating ADCC effects is reported here.•Antigen-specific antibody isolation using human plasma samples•Antibody-mediated cytotoxicity (ADCC).

20.
J Colloid Interface Sci ; 667: 529-542, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38653074

ABSTRACT

Diabetic wounds are characterized by chronic trauma, with long-term non-healing attributed to persistent inflammation and recurrent bacterial infections. Exacerbation of the inflammatory response is largely due to increased levels of reactive oxygen species (ROS). In this study, catalase (CAT) was used as a biological template to synthesize nanozyme-supported natural enzymes (CAT-Mn(SH)x) using a biomimetic mineralization method. Subsequently, polymyxin B (CAT-Mn(SH)x@PMB) was immobilized on its surface through electrostatic assembly. CAT-Mn(SH)x@PMB demonstrates the ability for slow and sustained release of hydrogen sulfide (H2S). Finally, CAT-Mn(SH)x@PMB loaded microneedles (MNs) substrate were synthesized using polyvinyl alcohol (PVA) and hydroxyethyl methacrylate (HEMA), and named CAT-(MnSH)x@PMB-MNs. It exhibited enhanced enzyme and antioxidant activities, along with effective antibacterial properties. Validation findings indicate that it can up-regulate the level of M2 macrophages and reduce the level of pro-inflammatory cytokine tumor necrosis factor-α (TNF-α). Additionally, it promotes angiogenesis and rapid nerve regeneration, thereby facilitating wound healing through its dual anti-inflammatory and antibacterial effects. Hence,this study introduces a time-space tissue-penetrating and soluble microneedle patch with dual anti-inflammatory and antibacterial effects for the treatment of diabetic wounds.

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