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1.
Front Psychiatry ; 15: 1336233, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38563030

RESUMO

Background: People living with HIV (PLWH) exhibits an increased susceptibility to anxiety disorders, concomitant with heightened vulnerability to aberrant immune activation and inflammatory responses, and endocrine dysfunction. There exists a dearth of scholarly investigations pertaining to the neurological, immune, and endocrine dimensions of HIV-associated anxiety disorders. Method: This study aimed to compare a group of 16 individuals diagnosed with HIV-associated anxiety disorders (HIV ANXs) according to the Diagnostic and statistical manual of mental disorders (5th ed.), with a HIV individual control group (HIV control) of 49 PLWH without mental disorders. Muti-modal magnetic resonance was employed to assess the brain function and structure of both groups. Seed-based functional connectivity (FC) was used to assess the regional intrinsic brain activity and the influence of regional disturbances on FC with other brain regions. Peripheral blood cytokines and chemokines concentrations were measured using liquid chip and ELISA. Results: Amplitude of low-frequency fluctuations in the right inferior temporal gyrus (ITG) was increased. There is a significant decreased regional homogeneity in HIV ANXs in the right superior occipital gyrus (SOG). The right ITG and the right SOG were separately set as the seed brain region of interest (ROI 1 and ROI 2) to be analyzed the FC. FC decreased in HIV ANXs between ROI1 and the right middle occipital gyrus, the right SOG, FC between ROI2 and left ITG increased in HIV ANXs. No significant structural difference was found between two groups. Pro-inflammatory chemokines showed higher levels in the HIV ANXs. Pro-inflammatory cytokines, neurotrophic factors, and endocrine factors were significantly correlated with alterations in brain function. Conclusion: This study suggests that patients with HIV-associated anxiety disorders may exhibit abnormalities in neurologic, immune, and endocrine functioning. Consequently, it is imperative to implement additional screening and intervention measures for anxiety disorders among PLWH.

2.
Nano Lett ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598773

RESUMO

The practical application of microsized anodes is hindered by severe volume changes and fast capacity fading. Herein, we propose a gradient composite strategy and fabricate a silicon suboxide-based composite anode (d-SiO@SiOx/C@C) consisting of a disproportionated microsized SiO inner core, a homogeneous composite SiOx/C interlayer (x ≈ 1.5), and a highly graphitized carbon outer layer. The robust SiOx/C interlayer can realize a gradient abatement of stress and simultaneously connect the inner SiO core and carbon outer layer through covalent bonds. As a result, d-SiO@SiOx/C@C delivers a specific capacity of 1023 mAh/g after 300 cycles at 1 A/g with a retention of >90% and an average Coulombic efficiency of >99.7%. A full cell assembled with a LiNi0.8Co0.15Al0.05O2 cathode displays a remarkable specific energy density of 569 Wh/kg based on total active materials as well as excellent cycling stability. Our strategy provides a promising alternative for designing structurally and electrochemically stable microsized anodes with high capacity.

3.
Front Cell Infect Microbiol ; 14: 1344778, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601742

RESUMO

Background: People living with HIV (PLWH) fail to achieve normalization of CD4+ T cell counts and function, especially in immunological non-responders (INRs). The frequencies of Ki67+CD4+ T cells were inversely associated with CD4+ T cell counts in HIV infected patients. Early ART did not normalize CD4+ T cell proliferation. However, the features of the abnormal proliferation CD4+ T cell in INRs are far from known. Method: PLWH were divided into INRs (n= 16) and immunological responders (IRs, n= 53) groups. Mass cytometry was applied to peripheral blood T cells to profile the immune cells and liquid chip technique was used to measure plasma levels of cytokines and chemokines. Correlation analyses were conducted to evaluate associations between the degree of CD4+ T cell proliferation and immune function. Results: The percentage of Ki67+ CD4+ T cells were significant higher in INRs, and we defined these cells with significant higher level of Ki67, as over-proliferating cells. No significant difference of markers' expression (HLA-DR, CD38, CD57, PD-1, PD-L1, CD107a, perforin) was found between INRs and IRs. Compared with naïve CD4+ T cells in INRs, Ki67+ CD4+ T cells exhibited lower levels of CD57 and CD38. Whereas Ki67+ T cells exhibited higher levels of CD38 and CD57 and activation compared with differentiated mature central memory CD4+ T cells and effector memory CD4+ T cells. Ki67+ cells did not show higher levels of senescence and activation compared to certain Ki67- CD4+ central memory T cells in IRs. Furthermore, Ki67+ CD4+ Tcm cells exhibited positive correlations with pro-inflammatory cytokines. Conclusion: We proposed and validated the hypothesis of "pathological proliferation" in INRs: excessive proliferation of CD4+ T cells in INRs may be accompanied by aberrant activation, senescence and loss of immune function. Eventually, such over-proliferating but poor-quality cells in INRs result in incomplete recovery of both CD4+ T cell counts and function. An intervention that enhancing the proliferative capacity or functional ability or both of CD4+ T cell in INRs might therefore be beneficial.


Assuntos
Linfócitos T CD4-Positivos , Infecções por HIV , Humanos , Antígeno Ki-67 , Proliferação de Células , Citocinas
4.
J Environ Manage ; 357: 120776, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38579468

RESUMO

Hydro-Fluctuation Belt (HFB), a periodically exposed bank area formed by changes in water level fluctuations, is critical for damaging the reservoir wetland landscape and ecological balance. Thus, it is important to explore the mechanism of hydrological conditions on the plant-soil system of the HFB for protection of the reservoir wetland and landscape restoration. Here, we investigated the response of plant community characteristics and soil environment of the HFB of Tonghui River National Wetland Park (China), is a typical reservoir wetland, to the duration of inundation, as well as the correlation between the distribution of dominant plants and soil pH, nutrient contents, and enzyme activity by linear regression and canonical correlation analyses. The results show that as the duration of inundation decreases, the vegetation within the HFB is successional from annual or biennial herbs to perennial herbs and shrubs, with dominant plant species prominent and uneven distribution of species. Soil nutrient contents and enzyme activities of HFB decreased with increasing inundation duration. Dominant species of HFB plant community are related to soil environment, with water content, pH, urease, and available potassium being principle soil environmental factors affecting their distribution. When HFB was inundated for 0-30 days, soil pH was strongly acidic, with available potassium content above 150 mg kg-1 and higher urease activity, distributed with Arundo donax L., Polygonum perfoliatum L., Alternanthera philoxeroides (Mart.) Griseb., and Daucus carota L. communities. When inundated for 30-80 days, soil pH was acidic, with lower available potassium content (50-150 mg kg-1) and urease activity, distributed with Beckmannia syzigachne (Steud.) Fern.+ Polygonum lapathifolium L., Polygonum lapathifolium L., Medicago lupulina L. + Dysphania ambrosioides L. and Leptochloa panicea (Retz.) Ohwi communities. Using the constructed HFB plant-soil correlation model, changes in the wetland soil environment can be quickly judged by the succession of plant dominant species, which provides a simpler method for the monitoring of the soil environment in the reservoir wetland, and is of great significance for the scientific management and reasonable protection of the reservoir-type wetland ecosystem.


Assuntos
Ecossistema , Áreas Alagadas , Solo/química , Urease , Plantas , Água , Poaceae , China , Potássio
5.
Int J Nanomedicine ; 19: 3475-3495, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38623080

RESUMO

Purpose: Human umbilical cord mesenchymal stem cell (hucMSC)-derived small extracellular vesicles (sEVs) are natural nanocarriers with promising potential in treating liver fibrosis and have widespread applications in the fields of nanomedicine and regenerative medicine. However, the therapeutic efficacy of natural hucMSC-sEVs is currently limited owing to their non-specific distribution in vivo and partial removal by mononuclear macrophages following systemic delivery. Thus, the therapeutic efficacy can be improved through the development of engineered hucMSC-sEVs capable to overcome these limitations. Patients and Methods: To improve the anti-liver fibrosis efficacy of hucMSC-sEVs, we genetically engineered hucMSC-sEVs to overexpress the anti-fibrotic gene bone morphogenic protein 7 (BMP7) in parental cells. This was achieved using lentiviral transfection, following which BMP7-loaded hucMSC-sEVs were isolated through ultracentrifugation. First, the liver fibrosis was induced in C57BL/6J mice by intraperitoneal injection of 50% carbon tetrachloride (CCL4) twice a week for 8 weeks. These mice were subsequently treated with BMP7+sEVs via tail vein injection, and the anti-liver fibrosis effect of BMP7+sEVs was validated using small animal in vivo imaging, immunohistochemistry (IHC), tissue immunofluorescence, and enzyme-linked immunosorbent assay (ELISA). Finally, cell function studies were performed to confirm the in vivo results. Results: Liver imaging and liver histopathology confirmed that the engineered hucMSC-sEVs could reach the liver of mice and aggregate around activated hepatic stellate cells (aHSCs) with a significantly stronger anti-liver fibrosis effect of BMP7-loaded hucMSC-sEVs compared to those of blank or negative control-transfected hucMSC-sEVs. In vitro, BMP7-loaded hucMSC-sEVs promoted the phenotypic reversal of aHSCs and inhibited their proliferation to enhance the anti-fibrotic effects. Conclusion: These engineered BMP7-loaded hucMSC-sEVs offer a novel and promising strategy for the clinical treatment of liver fibrosis.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Animais , Camundongos , Humanos , Células Estreladas do Fígado/patologia , Camundongos Endogâmicos C57BL , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/terapia , Cirrose Hepática/metabolismo , Fibrose , Vesículas Extracelulares/patologia , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical , Proteína Morfogenética Óssea 7/genética , Proteína Morfogenética Óssea 7/metabolismo
6.
Bioresour Technol ; : 130704, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38636879

RESUMO

In this study, a SNAD-SBBR process was implemented to achieve ammonia removal and carbon reduction of mature landfill leachate under extremely low dissolved oxygen conditions (0.051 mg/L) for a continuous operation of 266 days. The process demonstrated excellent removal performance, with ammonia nitrogen removal efficiency reaching 100 %, total nitrogen removal efficiency reaching 87.56 %, and an average removal rate of 0.180 kg/(m3·d). The recalcitrant organic compound removal efficiency reached 34.96 %. Nitrogen mass balance analysis revealed that the Anammox process contributed to approximately 98.1 % of the nitrogen removal. Candidatus Kuenenia achieved a relative abundance of 1.49 % in the inner layer of the carrier. In the SNAD-SBBR system, the extremely low DO environment created by the highly efficient partial nitrification stage enabled the coexistence of AnAOB, denitrifying bacteria, and Nitrosomonas, synergistically achieving ammonia removal and carbon reduction. Overall, the SNAD-SBBR process exhibits low-cost and high-efficiency characteristics, holding tremendous potential for landfill leachate treatment.

7.
J Phys Chem Lett ; : 4669-4678, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651977

RESUMO

The Zn dendrite and hydrogen evolution reaction have been a "stubborn illness" for the life span of zinc anodes, which significantly hinders the development of aqueous zinc batteries (AZBs). Herein, considering the ingenious molecular structure, a multifunctional additive based on the synergistic regulation of cations and anions at the interface is designed to promote a dendrite-free and stable Zn anode. Theoretical calculations and characterization results verified that the electrostatic shield effect of the cation, the solvation sheath structure, and the bilayer structural solid electrolyte film (SEI) jointly account for the uniform Zn deposition and side reaction suppression. Ultimately, a remarkably high average Coulombic efficiency (CE) of 99.4% is achieved in the Zn||Cu cell for 300 cycles, and a steady charge/discharge cycling over 3000 and 300 h at 1.0 mA cm-2/1.0 mAh cm-2 and 10 mA cm-2/10 mAh cm-2 is obtained in the Zn||Zn cell. Furthermore, the assembled full battery demonstrates a prolonged cycle life of 2000 cycles.

8.
Transl Cancer Res ; 13(3): 1367-1381, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38617526

RESUMO

Background: Head and neck squamous cell carcinoma (HNSCC) is the most common type and accounts for 90% of all head and neck cancer cases. Despite advances in early diagnosis and treatment strategies-chemotherapy, surgical resection, and radiotherapy-5-year survival remains grim. For patients with early-stage HNSCC, accurately predicting clinical outcomes is challenging. Considering the pivotal role of the immune system in HNSCC, we developed a reliable immune-related gene signature (IRGS) and explored its predictive accuracy in patients with early-stage HNSCC. Methods: We examined immune gene expression profiles and clinical information from 230 early-stage HNSCC specimens, including 100 cases from The Cancer Genome Atlas (TCGA), 49 cases from the Gene Expression Omnibus (GEO; GSE65858), and 81 cases from an independent clinical cohort. The prognostic signature was constructed using Kaplan-Meier analysis and the least absolute shrinkage and selection operator (LASSO) Cox algorithm. We also explored the IRGS-related biological pathways and immune landscape using bioinformatics analysis. Results: A nine-immune-gene signature was generated to significantly stratify patients into high and low-risk groups. High risk patients exhibited shorter survival time [hazard ratio (HR) =13.795, 95% confidence interval (CI): 3.275-58.109, P<0.001]. The signature demonstrated robust prognostic ability in the training and validation sets and could independently predict overall survival (OS) and relapse-free survival (RFS). Subsequently, the receiver operating characteristic (ROC) curve and C-index confirmed the signature's predictive accuracy compared to clinical parameters. Additionally, cases classified as low risk showed more immune cell infiltration than high-risk cases. Conclusions: Our novel IRGS is a reliable and robust classifier for accurate patient stratification and prognostic evaluation. Future studies will attempt to affirm the signature's clinical application to early-stage HNSCC.

9.
Front Microbiol ; 15: 1361756, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38591034

RESUMO

Phyllosphere microbes residing on plant leaf surfaces for maintaining plant health have gained increasing recognition. However, in desert ecosystems, knowledge about the variety, composition, and coexistence patterns of microbial communities in the phyllosphere remains limited. This study, conducted across three basins (Turpan-TLF, Tarim-CL, and Dzungaria-MSW) and three seasons (spring, summer, and autumn) in Xinjiang, China, aimed to explore the diversity and composition of microbial communities in the phyllosphere, encompassing both bacteria and fungi in Alhagi sparsifolia. We also investigated the co-occurrence patterns, influencing factors, and underlying mechanisms driving these dynamics. Results indicate that phyllosphere bacteria exhibited lower diversity indices (ACE, Shannon, Simpson, Fisher phylogenetic diversity, and Richness) in spring compared to summer and autumn, while the Goods Coverage Index (GCI) was higher in spring. Conversely, diversity indices and GCI of phyllosphere fungi showed an opposite trend. Interestingly, the lowest level of multi-functionality and niche width in phyllosphere bacteria occurred in spring, while the highest level was observed in phyllosphere fungi. Furthermore, the study revealed that no significant differences in multi-functionality were found among the regions (CL, MSW, and TLF). Network analysis highlighted that during spring, phyllosphere bacteria exhibited the lowest number of nodes, edges, and average degree, while phyllosphere fungi had the highest. Surprisingly, the multi-functionality of both phyllosphere bacteria and fungi showed no significant correlation with climatic and environmental factors but displayed a significant association with the morphological characteristics and physicochemical properties of leaves. Structural Equation Model indicated that the morphological characteristics of leaves significantly influenced the multi-functionality of phyllosphere bacteria and fungi. However, the indirect and total effects of climate on multi-functionality were greater than the effects of physicochemical properties and morphological characteristics of leaves. These findings offer new insights into leaf phyllosphere microbial community structure, laying a theoretical foundation for vegetation restoration and rational plant resource utilization in desert ecosystems.

10.
Int J Nanomedicine ; 19: 2591-2610, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505167

RESUMO

Extracellular vesicles can transmit intercellular information and transport biomolecules to recipient cells during various pathophysiological processes in the organism. Animal cell exosomes have been identified as potential nanodrugs delivery vehicles, yet they have some shortcomings such as high immunogenicity, high cytotoxicity, and complicated preparation procedures. In addition to exosomes, plant-derived extracellular vesicles (PDVs), which carry a variety of active substances, are another promising nano-transport vehicles emerging in recent years due to their stable physicochemical properties, wide source, and low cost. This work briefly introduces the collection and characterization of PDVs, then focuses on the application of PDVs as natural or engineered drug carriers in biomedicine, and finally discusses the development and challenges of PDVs in future applications.


Assuntos
Exossomos , Vesículas Extracelulares , Animais , Sistemas de Liberação de Medicamentos/métodos , Portadores de Fármacos
11.
ACS Nano ; 18(13): 9511-9524, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38499440

RESUMO

Glioblastoma multiforme (GBM) is the most aggressive and lethal form of human brain tumors. Dismantling the suppressed immune microenvironment is an effective therapeutic strategy against GBM; however, GBM does not respond to exogenous immunotherapeutic agents due to low immunogenicity. Manipulating the mitochondrial electron transport chain (ETC) elevates the immunogenicity of GBM, rendering previously immune-evasive tumors highly susceptible to immune surveillance, thereby enhancing tumor immune responsiveness and subsequently activating both innate and adaptive immunity. Here, we report a nanomedicine-based immunotherapeutic approach that targets the mitochondria in GBM cells by utilizing a Trojan-inspired nanovector (ABBPN) that can cross the blood-brain barrier. We propose that the synthetic photosensitizer IrPS can alter mitochondrial electron flow and concurrently interfere with mitochondrial antioxidative mechanisms by delivering si-OGG1 to GBM cells. Our synthesized ABBPN coloaded with IrPS and si-OGG1 (ISA) disrupts mitochondrial electron flow, which inhibits ATP production and induces mitochondrial DNA oxidation, thereby recruiting immune cells and endogenously activating intracranial antitumor immune responses. The results of our study indicate that strategies targeting the mitochondrial ETC have the potential to treat tumors with limited immunogenicity.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/patologia , Barreira Hematoencefálica/patologia , Elétrons , Transporte Biológico , Neoplasias Encefálicas/genética , Mitocôndrias , Linhagem Celular Tumoral , Microambiente Tumoral
12.
Bioresour Technol ; 399: 130553, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460559

RESUMO

Considering the challenges associated with nitrogen removal from mature landfill leachate, a novel combined continuous-flow process integrating denitrification and partial nitrification-Anammox (PN/A) was developed using an internal circulation (IC) system and a biological aerated filter (BAF) biofilm reactor (IBBR). In this study, IBBR successfully operated for 343 days, and when influent NH4+-N concentration of mature landfill leachate reached 1258.1 mg/L, an impressive total nitrogen removal efficiency (TNRE) of 93.3 % was achieved, along with a nitrogen removal rate (NRR) of 1.13 kg N/(m3·d). The analysis of the microbial community revealed that Candidatus Kuenenia, the dominant genus responsible for anammox, accounted for 1.7 % (day 265). Additionally, Nitrosomonas, Thauera and Truepera were identified as key contributors to the efficient removal of nitrogen from mature landfill. As a novel nitrogen removal strategy, the practical application of the IBBR system offers novel perspectives on addressing mature landfill leachate.


Assuntos
Nitrificação , Poluentes Químicos da Água , Desnitrificação , Nitrogênio , Oxidação Anaeróbia da Amônia , Reatores Biológicos , Oxirredução , Esgotos
13.
Mol Plant ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38486452

RESUMO

Understanding the underlying mechanisms and links between genome evolution and adaptive innovations stands as a key goal in evolutionary studies. Poplars, among the world's most widely distributed and cultivated trees, exhibit extensive phenotypic diversity and environmental adaptability. In this study, we present a genus-level super-pangenome comprising 19 Populus genomes, revealing the likely pivotal role of private genes in facilitating local environmental and climate adaptation. Through the integration of pangenomes with transcriptomes, methylomes, and chromatin accessibility mapping, we unveil that the evolutionary trajectories of pangenes and duplicated genes are closely linked to local genomic landscapes of regulatory and epigenetic architectures, notably CG methylation in gene-body regions. Further comparative genomic analyses have enabled the identification of 142 202 structural variants across species that intersect with a significant number of genes and contribute substantially to both phenotypic and adaptive divergence. We have experimentally validated a ∼180-bp presence/absence variant affecting the expression of the CUC2 gene, crucial for leaf serration formation. Finally, we developed a user-friendly web-based tool encompassing the multi-omics resources associated with the Populus super-pangenome (http://www.populus-superpangenome.com). Together, the present pioneering super-pangenome resource in forest trees not only aids in the advancement of breeding efforts of this globally important tree genus but also offers valuable insights into potential avenues for comprehending tree biology.

14.
J Hazard Mater ; 470: 134102, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38554506

RESUMO

The inappropriate use of antibiotics is widely recognized as the primary driver of bacterial antibiotic resistance. However, less attention has been given to the potential induction of multidrug-resistant bacteria through exposure to disinfectants. In this study, Klebsiella pneumonia, an opportunistic pathogen commonly associated with hospital and community-acquired infection, was experimentally exposed to NaClO at both minimum inhibitory concentration (MIC) and sub-MIC levels over a period of 60 days. The result demonstrated that NaClO exposure led to enhanced resistance of K. pneumonia to both NaClO itself and five antibiotics (erythromycin, polymyxin B, gentamicin, tetracycline, and ciprofloxacin). Concurrently, the evolved resistant strains exhibited fitness costs, as evidenced by decreased growth rates. Whole population sequencing revealed that both concentrations of NaClO exposure caused genetic mutations in the genome of K. pneumonia. Some of these mutations were known to be associated with antibiotic resistance, while others had not previously been identified as such. In addition, 11 identified mutations were located in the virulence factors, demonstrating that NaClO exposure may also impact the pathogenicity of K. pneumoniae. Overall, this study highlights the potential for the widespread use of NaClO-containing disinfectants during the COVID-19 pandemic to contribute to the emergence of antibiotic-resistant bacteria. ENVIRONMENTAL IMPLICATION: Considering the potential hazardous effects of disinfectant residues on environment, organisms and biodiversity, the sharp rise in use of disinfectants during COVID-19 pandemic has been considered highly likely to cause worldwide secondary disasters in ecosystems and human health. This study demonstrated that NaClO exposure enhanced the resistance of K. pneumonia to both NaClO and five antibiotics (erythromycin, polymyxin B, gentamicin, tetracycline, and ciprofloxacin), highlighting the widespread use of NaClO-containing disinfectants during the COVID-19 pandemic may increase the emergence of antibiotic-resistant bacteria in the environment.


Assuntos
Antibacterianos , COVID-19 , Desinfetantes , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Antibacterianos/farmacologia , Humanos , Hipoclorito de Sódio/farmacologia , Farmacorresistência Bacteriana , SARS-CoV-2/efeitos dos fármacos , Mutação , Farmacorresistência Bacteriana Múltipla , Infecções por Klebsiella/tratamento farmacológico
15.
Anal Chim Acta ; 1297: 342351, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38438235

RESUMO

Cholesterol is an important lipid compound found in a variety of foods, and its level in human blood is closely related to human health. Therefore, development of rapid and accurate POCT (point-of-care testing) methods for cholesterol detection is crucial for assessing food quality and early diagnosis of diseases, in particular, in a resource-limited environment. In this study, a smartphone-assisted colorimetric biosensor is constructed based on platinum,phosphorus-codoped carbon nitride (PtCNP2) for the rapid detection of cholesterol. Phosphorus-doped carbon nitride is prepared by thermal annealing of urea and NH4PF6, into which platinum is atomically dispersed by thermal refluxing. The obtained PtCNP2 exhibits an excellent peroxidase-like activity under physiological pH, whereby colorless o-phenylenediamine (OPD) is oxidized to colored 2,3-diaminophenazine (DAP) in the presence of hydrogen peroxide (H2O2), which can be produced during the oxidation of cholesterol by cholesterol oxidase. A smartphone-assisted visual sensing system is then constructed based on the color recognition software, and rapid on-site detection of cholesterol is achieved by reading the RGB values. Meanwhile, the generated DAP shows an apparent fluorescence signal and can realize highly sensitive detection of cholesterol by the change of the fluorescence signal intensity. Such a cholesterol sensor exhibits a wide linear detection range of 0.5-600 µg mL-1 and a low detection limit of 59 ng mL-1. The practicality of the sensor is successfully demonstrated in the rapid detection of cholesterol in serum and food.


Assuntos
Colorimetria , Peróxido de Hidrogênio , Nitrilas , Humanos , Platina , Colesterol , Fósforo
16.
Ying Yong Sheng Tai Xue Bao ; 35(2): 289-297, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38523085

RESUMO

To explore potential responses of ecosystem carbon density to changes of community structure during natural regeneration of woody plants, we analyzed the relationships between ecosystem carbon density and its components, tree species diversity, structural diversity (CVDBH) and spatial structure parameters (mingling, aggregation, dominance, crowding) of Cunninghamia lanceolata forests with different sprouting densities (1154, 847 and 465 individuals·hm-2) at the early stage of succession in Baishanzu National Park. The results showed that tree species diversity (species richness index and Shannon diversity index) increased with the decrease of sprouting density of C. lanceolata. Among the stand structural parameters, CVDBH, stand density, and mingling increased with the decrease of sprouting density of C. lanceolata. The stand distribution pattern of different C. lanceolata densities was uniform, with sub-dominant stand growth status and relatively dense status. The carbon density of tree layer under high, medium, and low sprouting densities of C. lanceolata were 57.56, 56.12 and 46.54 t·hm-2, soil carbon density were 104.35, 122.71 and 142.00 t·hm-2, and the total carbon density of ecosystem were 164.59, 182.41 and 190.13 t·hm-2, respectively. There was little variation in carbon density of understory layer and litter layer among different treatments. The carbon density distribution characteristics of different C. lanceolata densities were following the order of soil layer (63.4%-74.7%) > tree layer (24.5%-35.0%) > understory layer and litter layer (0.8%-2.0%). The results of variance partitioning analysis indicated that the change of tree layer carbon density was mainly influenced by stand structure diversity, soil layer carbon density was influenced by both tree species diversity and stand structure diversity, while ecosystem carbon density was mainly influenced by tree species diversity. Stand spatial structure parameters had a relatively little effect on ecosystem carbon density and its components. The sprouting density of C. lanceolata significantly affected ecosystem carbon accumulation during the conversion from C. lanceolata plantations to natural forests. A lower remaining density of C. lanceolata (about 500 individuals·hm-2) was more conducive to forest carbon sequestration.


Assuntos
Cunninghamia , Ecossistema , Humanos , Carbono/química , Florestas , Árvores , Solo/química , China
17.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38474887

RESUMO

With the increasing use of open-source libraries and secondary development, software projects face security vulnerabilities. Existing studies on source code vulnerability detection rely on natural language processing techniques, but they overlook the intricate dependencies in programming languages. To address this, we propose a framework called Context and Multi-Features-based Vulnerability Detection (CMFVD). CMFVD integrates source code graphs and textual sequences, using a novel slicing method called Context Slicing to capture contextual information. The framework combines graph convolutional networks (GCNs) and bidirectional gated recurrent units (BGRUs) with attention mechanisms to extract local semantic and syntactic information. Experimental results on Software Assurance Reference Datasets (SARDs) demonstrate CMFVD's effectiveness, achieving the highest F1-score of 0.986 and outperforming other models. CMFVD offers a promising approach to identifying and rectifying security flaws in large-scale codebases.

18.
Curr Med Imaging ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454768

RESUMO

BACKGROUND: Pyogenic liver abscess (PLA) is a purulent disease caused by microbial contamination of liver parenchyma and includes amoebic liver abscess, fungal liver abscess, and the most common bacterial liver abscess. OBJECTIVE: Explore the efficacy of contrast-enhanced ultrasound (CEUS) via vessels and surgical drain guidance percutaneous catheter drainage (PCD) in the treatment of pyogenic liver abscesses (PLA). MATERIALS AND METHODS: A total of 86 PLA patients who underwent PCD treatment in our hospital from May 2018 to February 2023 were retrospectively selected. Of them, 41 patients were treated under intravenous CEUS guidance (Control group), and 45 patients were treated under CEUS via vessels and surgical drain guidance (study group). Perioperative characteristics, treatment effectiveness, and incidence of complications were analyzed and compared between groups. RESULTS AND DISCUSSION: The duration of surgery, drainage, white blood cell recovery, body temperature recovery, and hospitalization in the study group were longer than those in the control group (P<0.05). The total effective rate of the study group (95.56%) was higher than that of the control group (80.49%) (P<0.05). The incidence of complications in the study group (4.44%) was lower than that in the control group (19.51%) (P<0.05). CONCLUSION: Compared with intravenous CEUS alone, treatment under CEUS via vessels and surgical drains-guided PCD was associated with shorter surgical time, faster recovery, better treatment effect, lower risk of complications, and ensured treatment safety in PLA patients.

19.
Phys Chem Chem Phys ; 26(7): 6256-6264, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38305726

RESUMO

Finding materials with suitable thermal conductivity (κ) is crucial for improving energy efficiency, reducing carbon emissions, and achieving sustainability. Atomic substitution and structural adjustments are commonly used methods. By comparing the κ of two different structures of two-dimensional (2D) IIIA-nitrides and their corresponding carbides, we explored whether atomic substitution has the same impact on κ in different structures. All eight materials exhibit normal temperature dependence, with κ decreasing as the temperature rises. Both structures are single atomic layers of 2D materials, forming M-N bonds, with the difference being that H-MN consists of hexagonal rings, while T-MN consists of tetragonal and octagonal rings. 2D IIIA-nitrides provide a good illustration of the impact of atomic substitution and structure on κ. On a logarithmic scale of κ, it approximates two parallel lines, indicating that different structures exhibit similar trends of κ reduction under the same conditions of atomic substitution. We analyzed the mechanisms behind the decreasing trend in κ from a phonon mode perspective. The main reason for the decrease in κ is that heavier atoms lower lattice vibrations, reducing phonon frequencies. Electronegativity increases, altering bonding characteristics and increasing anharmonicity. Reduced symmetry in complex structures decreases phonon group velocities and enhances phonon anharmonicity, leading to decreased phonon lifetimes. It's noteworthy that we found that atomic substitution and structure significantly affect hydrodynamic phonon transport as well. Both complex structures and atomic substitution simultaneously reduce the effects of hydrodynamic phonon transport. By comparing the impact of κ on two different structures of 2D IIIA-nitrides and their corresponding carbides, we have deepened our understanding of phonon transport in 2D materials. Heavier atomic substitution and more complex structures result in reduced κ and decreased hydrodynamic phonon transport effects. This research is likely to have a significant impact on the study of micro- and nanoscale heat transfer, including the design of materials with specific heat transfer properties for future applications.

20.
J Sci Food Agric ; 104(7): 4425-4437, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38349056

RESUMO

BACKGROUND: Diminished ovarian reserve has a serious impact on female reproduction with an increasing incidence every year. An important cause of this is oxidative stress. Rubi fructus, a traditional medicinal and edible plant, has shown therapeutic effects against gynecological diseases. Vanillic acid, isoquercitrin, kaempferol-3-O-rutinoside, kaempferol-3-O-sophoroside, oleanolic acid, tormentic acid, tiliroside, and ellagic acid are the major bioactive components in R. fructus. However, studies involved in the effectiveness and mechanism of these components in oxidative stress-induced ovarian dysfunction are scarce. RESULTS: In this study, the protective mechanisms of the bioactive components were evaluated in human ovarian granulosa cells. Isoquercitrin was significantly superior to other bioactive components in relieving damage in human ovarian granulosa cells induced by 2,2-azobis (2-methylpropionamidine) dihydrochloride, considering enhanced cell viability, reduced reactive oxygen species accumulation, and improved mitochondrial membrane potential level. Isoquercitrin protected human ovarian granulosa cells from oxidative stress by regulating the enzyme activity of glutathione peroxidase, inhibiting cell apoptosis, improving the expression of genes related to oxidative stress, and ameliorating heme oxygenase 1 protein expression. CONCLUSION: Isoquercitrin, a bioactive component in R. fructus, has a significant protective effect on oxidative damage induced by 2,2-azobis (2-methylpropionamidine) dihydrochloride in human ovarian granulosa cells, providing evidence for its potential application in protecting ovarian function. © 2024 Society of Chemical Industry.


Assuntos
Antioxidantes , Estresse Oxidativo , Feminino , Humanos , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células da Granulosa/metabolismo , Apoptose
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