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1.
ACS Nano ; 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613506

RESUMO

A Na4MnV(PO4)3 (NMVP) cathode is regarded as a promising cathode candidate for sodium-ion batteries (SIBs). However, issues such as low electronic conductivity and partial cation dissolution contribute to high polarization and structure distortion. Herein, we engineered the local electron density and reaction kinetic properties of NMVP cathodes with varying oxygen vacancies by introducing varying amounts of Zr doping and carbon coating. The optimized sample exhibited a high-rate capacity of 71.8 mAh g-1 at 30 C (83.1% capacity retention after 1000 cycles) and excellent performance over a wide temperature range (84.1 mAh g-1 at 60 °C and 61.4 mAh g-1 at -30 °C). In situ X-ray diffraction technology confirmed a redox solid solution and a two-phase reaction mechanism, revealing minor changes in cell volume and slight strain variations after Zr doping, effectively suppressing the structural distortion. Theoretical calculations illustrated that Zr doping largely shrinks the band gap of NMVP, enriches local electron density, and slightly alters the local element distribution and bond lengths. Moreover, full-cells have shown high energy density (259.9 Wh kg-1) and outstanding cycling stability (200 cycles). The work provides fresh insights into the synergistic effect of strain suppressing and interface engineering in promoting the development of wide temperature range and long-calendar-life SIBs.

2.
Opt Express ; 32(6): 9958-9966, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571219

RESUMO

In this study, a three-dimensional (3D) laser micromachining system with an integrated sub-100 nm resolution in-situ measurement system was proposed. The system used the same femtosecond laser source for in-situ measurement and machining, avoiding errors between the measurement and the machining positions. It could measure the profile of surfaces with an inclination angle of less than 10°, and the measurement resolution was greater than 100 nm. Consequently, the precise and stable movement of the laser focus could be controlled, enabling highly stable 3D micromachining. The results showed that needed patterns could be machined on continuous surfaces using the proposed system. The proposed machining system is of great significance for broadening the application scenarios of laser machining.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38603469

RESUMO

The electrochemical interface formed between an electrode and an electrolyte significantly affects the rate and mechanism of the electrode reaction through its structure and properties, which vary across the interface. The scope of the interface has been expanded, along with the development of energy electrochemistry, where a solid-electrolyte interphase may form on the electrode and the active materials change properties near the surface region. Developing a comprehensive understanding of electrochemical interfaces and interphases necessitates three-dimensional spatial resolution characterization. Atomic force microscopy (AFM) offers advantages of imaging and long-range force measurements. Here we assess the capabilities of AFM by comparing the force curves of different regimes and various imaging modes for in situ characterizing of electrochemical interfaces and interphases. Selected examples of progress on work related to the structures and processes of electrode surfaces, electrical double layers, and lithium battery systems are subsequently illustrated. Finally, this review provides perspectives on the future development of electrochemical AFM.

4.
BMC Med ; 22(1): 146, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38561734

RESUMO

BACKGROUND: Childhoods in urban or rural environments may differentially affect the risk of neuropsychiatric disorders, possibly through memory processing and neural response to emotional stimuli. Genetic factors may not only influence individuals' choices of residence but also modulate how the living environment affects responses to episodic memory. METHODS: We investigated the effects of childhood urbanicity on episodic memory in 410 adults (discovery sample) and 72 adults (replication sample) with comparable socioeconomic statuses in Beijing, China, distinguishing between those with rural backgrounds (resided in rural areas before age 12 and relocated to urban areas at or after age 12) and urban backgrounds (resided in cities before age 12). We examined the effect of childhood urbanicity on brain function across encoding and retrieval sessions using an fMRI episodic memory paradigm involving the processing of neutral or aversive pictures. Moreover, genetic association analyses were conducted to understand the potential genetic underpinnings that might contribute to memory processing and neural mechanisms influenced by early-life urban or rural environments. RESULTS: Episodic memory retrieval accuracy for more difficult neutral stimuli was similar between those with urban and rural childhoods, whereas aversive stimuli elicited higher retrieval accuracy in the urban group (P = 0.023). For aversive stimuli, subjects with urban childhood had relatively decreased engagement of the striatum at encoding and decreased engagement of the hippocampus at retrieval. This more efficient striatal encoding of aversive stimuli in those with urban childhoods was associated with common variation in neurotrophic tyrosine kinase receptor type 2 (NTRK2) (right striatum: P = 1.58×10-6). These findings were confirmed in the replication sample. CONCLUSIONS: We suggest that this differential striatal processing of aversive stimuli observed in individuals with urban or rural childhoods may represent mechanisms by which childhood urbanicity may affect brain circuits, heightening behavioral responses to negative stressors associated with urban environments. NTRK2-associated neural processes in the striatum may play a role in these processes.


Assuntos
Memória Episódica , Adulto , Criança , Humanos , Mapeamento Encefálico , Emoções/fisiologia , Hipocampo , Imageamento por Ressonância Magnética , Receptor trkB
5.
Cell Prolif ; : e13614, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499435

RESUMO

Ex vivo red blood cell (RBC) production generates unsatisfactory erythroid cells. A deep exploration into terminally differentiated cells is required to understand the impairments for RBC generation and the underlying mechanisms. Here, we mapped an atlas of terminally differentiated cells from umbilical cord blood mononuclear cells (UCBMN) and pluripotent stem cells (PSC) and observed their dynamic regulation of erythropoiesis at single-cell resolution. Interestingly, we detected a few progenitor cells and non-erythroid cells from both origins. In PSC-derived erythropoiesis (PSCE), the expression of haemoglobin switch regulators (BCL11A and ZBTB7A) were significantly absent, which could be the restraint for its adult globin expression. We also found that PSCE were less active in stress erythropoiesis than in UCBMN-derived erythropoiesis (UCBE), and explored an agonist of stress erythropoiesis gene, TRIB3, could enhance the expression of adult globin in PSCE. Compared with UCBE, there was a lower expression of epigenetic-related proteins (e.g., CASPASE 3 and UBE2O) and transcription factors (e.g., FOXO3 and TAL1) in PSCE, which might restrict PSCE's enucleation. Moreover, we characterized a subpopulation with high proliferation capacity marked by CD99high in colony-forming unit-erythroid cells. Inhibition of CD99 reduced the proliferation of PSC-derived cells and facilitated erythroid maturation. Furthermore, CD99-CD99 mediated the interaction between macrophages and erythroid cells, illustrating a mechanism by which macrophages participate in erythropoiesis. This study provided a reference for improving ex vivo RBC generation.

6.
Fitoterapia ; 175: 105910, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38479619

RESUMO

Three new indole alkaloid derivatives, fissindoalkas A-C (1-3) together with one known biogenetically related polysubstituted indole alkaloid (4) were isolated from the roots of Fissistigma oldhamii (Hemsl.) Merr. The structures of compounds 1-4 were elucidated using comprehensive spectroscopic methods. The inhibitory activities of compounds 1-4 against nitric oxide (NO) production induced by lipopolysaccharide (LPS) were evaluated in vitro using mouse macrophage RAW264.7 cells. Compounds 2 and 3 showed potent inhibitory activities on NO production with IC50 values of 2.52 ± 0.18 and 2.33 ± 0.16 µM. These results indicate that the discovery of indole alkaloid derivatives, from the roots of F. oldhamii, which show significant anti-inflammatory properties, could be of great importance to the research and for the development of novel natural anti-inflammatory agents.

7.
Int J Rheum Dis ; 27(3): e15090, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38443978

RESUMO

OBJECTIVES: Steroid-induced osteonecrosis of the femoral head (SONFH) is characterized by impaired osteogenesis in bone marrow mesenchymal stem cells (BMSCs). This study investigates the role of lysine-specific demethylase 5A (KDM5A) in SONFH to identify potential therapeutic targets. METHODS: Human BMSCs were isolated and characterized for cell surface markers and differentiation capacity. A SONFH cell model was established using dexamethasone treatment. BMSCs were transfected with KDM5A overexpression vectors or si-KDM5A, and the expression of KDM5A, miR-107, runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), and osteopontin (OPN) was assessed. Alizarin red staining was used to observe mineralization nodules, while alkaline phosphatase activity and cell viability were measured. The enrichment of KDM5A and histone 3 lysine 4 trimethylation (H3K4me3) on the promoters of RUNX2, OCN, and OPN was analyzed. The binding between miR-107 and KDM5A 3'UTR was validated, and the combined effect of miR-107 overexpression and KDM5A overexpression on BMSC osteogenic differentiation was evaluated. RESULTS: KDM5A was upregulated in BMSCs from SONFH. Inhibition of KDM5A promoted osteogenic differentiation of BMSCs, associated with increased RUNX2, OCN, and OPN promoters. KDM5A bound to the promoters of RUNX2, OCN, and OPN, leading to reduced H3K4me3 levels and downregulation of their expression. Overexpression of miR-107 inhibited KDM5A and enhanced BMSC osteogenic differentiation. CONCLUSION: KDM5A negatively regulates BMSC osteogenic differentiation by modulating H3K4me3 levels on the promoters of key osteogenic genes. miR-107 overexpression counteracts the inhibitory effect of KDM5A on osteogenic differentiation. These findings highlight the potential of targeting the KDM5A/miR-107 axis for SONFH therapy.


Assuntos
Células-Tronco Mesenquimais , MicroRNAs , Humanos , Histonas , Subunidade alfa 1 de Fator de Ligação ao Core , Osteogênese , Cabeça do Fêmur , Lisina , MicroRNAs/genética , Proteína 2 de Ligação ao Retinoblastoma/genética
8.
Ann Surg Oncol ; 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38520581

RESUMO

BACKGROUND: Noninvasively and accurately predicting subcarinal lymph node metastasis (SLNM) for patients with non-small cell lung cancer (NSCLC) remains challenging. This study was designed to develop and validate a tumor and subcarinal lymph nodes (tumor-SLNs) dual-region computed tomography (CT) radiomics model for predicting SLNM in NSCLC. METHODS: This retrospective study included NSCLC patients who underwent lung resection and SLNs dissection between January 2017 and December 2020. The radiomic features of the tumor and SLNs were extracted from preoperative CT, respectively. Ninety machine learning (ML) models were developed based on tumor region, SLNs region, and tumor-SLNs dual-region. The model performance was assessed by the area under the curve (AUC) and validated internally by fivefold cross-validation. RESULTS: In total, 202 patients were included in this study. ML models based on dual-region radiomics showed good performance for SLNM prediction, with a median AUC of 0.794 (range, 0.686-0.880), which was superior to those of models based on tumor region (median AUC, 0.746; range, 0.630-0.811) and SLNs region (median AUC, 0.700; range, 0.610-0.842). The ML model, which is developed by using the naive Bayes algorithm and dual-region features, had the highest AUC of 0.880 (range of cross-validation, 0.825-0.937) among all ML models. The optimal logistic regression model was inferior to the optimal ML model for predicting SLNM, with an AUC of 0.727. CONCLUSIONS: The CT radiomics showed the potential for accurately predicting SLNM in NSCLC patients. The ML model with dual-region radiomic features has better performance than the logistic regression or single-region models.

9.
J Colloid Interface Sci ; 665: 188-203, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38522159

RESUMO

Anti-tumor therapies reliant on reactive oxygen species (ROS) as primary therapeutic agents face challenges due to a limited oxygen substrate. Photodynamic therapy (PDT) is particularly hindered by inherent hypoxia, while chemodynamic therapy (CDT) encounters obstacles from insufficient endogenous hydrogen peroxide (H2O2) levels. In this study, we engineered biodegradable tumor microenvironment (TME)-activated hollow mesoporous MnO2-based nanotheranostic agents, designated as HAMnO2A. This construct entails loading artemisinin (ART) into the cavity and surface modification with a mussel-inspired polymer ligand, namely hyaluronic acid-linked poly(ethylene glycol)-diethylenetriamine-conjugated (3,4-dihydroxyphenyl) acetic acid, and the photosensitizer Chlorin e6 (mPEG-HA-Dien-(Dhpa/Ce6)), facilitating dual-modal imaging-guided PDT/CDT synergistic therapy. In vitro experimentation revealed that HAMnO2A exhibited ideal physiological stability and enhanced cellular uptake capability via CD44-mediated endocytosis. Additionally, it was demonstrated that accelerated endo-lysosomal escape through the pH-dependent protonation of Dien. Within the acidic and highly glutathione (GSH)-rich TME, the active component of HAMnO2A, MnO2, underwent decomposition, liberating oxygen and releasing both Mn2+ and ART. This process alleviates hypoxia within the tumor region and initiates a Fenton-like reaction through the combination of ART and Mn2+, thereby enhancing the effectiveness of PDT and CDT by generating increased singlet oxygen (1O2) and hydroxyl radicals (•OH). Moreover, the presence of Mn2+ ions enabled the activation of T1-weighted magnetic resonance imaging. In vivo findings further validated that HAMnO2A displayed meaningful tumor-targeting capabilities, prolonged circulation time in the bloodstream, and outstanding efficacy in restraining tumor growth while inducing minimal damage to normal tissues. Hence, this nanoplatform serves as an efficient all-in-one solution by facilitating the integration of multiple functions, ultimately enhancing the effectiveness of tumor theranostics.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Compostos de Manganês/farmacologia , Compostos de Manganês/química , Microambiente Tumoral , Nanomedicina Teranóstica/métodos , Peróxido de Hidrogênio/química , Óxidos/química , Fármacos Fotossensibilizantes/química , Neoplasias/tratamento farmacológico , Oxigênio , Hipóxia/tratamento farmacológico , Linhagem Celular Tumoral , Nanopartículas/química
10.
Materials (Basel) ; 17(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38473496

RESUMO

To address the most significant environmental challenges, the quest for high-performance gas sensing materials is crucial. Among numerous two-dimensional materials, this study investigates the gas-sensitive capabilities of monolayer As, Sb, and Bi materials. To compare the gas detection abilities of these three materials, we employ first-principles calculations to comprehensively study the adsorption behavior of NO and NO2 gas molecules on the material surfaces. The results indicate that monolayer Bi material exhibits reasonable adsorption distances, substantial adsorption energies, and significant charge transfer for both NO and NO2 gases. Therefore, among the materials studied, it demonstrates the best gas detection capability. Furthermore, monolayer As and Sb materials exhibit remarkably high capacities for adsorbing NO and NO2 gas molecules, firmly interacting with the gas molecules. Gas adsorption induces changes in the material's work function, suggesting the potential application of these two materials as catalysts.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38450723

RESUMO

BACKGROUND: The effect of a healthy lifestyle on dementia associated with multimorbidity is not well understood. Our objective is to examine whether the adoption of a healthy lifestyle could potentially reduce the elevated risk of dementia in individuals with and without multimorbidity. METHODS: We utilized data from the UK Biobank cohort. A comprehensive healthy lifestyle score, ranging from 0 to 6, was generated. Cox proportional hazards models were used to examine the associations between multimorbidity, the healthy lifestyle score, and the incidence risk of dementia. RESULTS: Over a median follow-up period of 12.5 years, 5 852 all-cause dementia were recorded. Multimorbidity including cardiovascular, metabolic, neuropsychiatric, and inflammation-related diseases was associated with a higher risk of subsequent dementia. Each additional chronic disease was associated with a hazard ratio (HR) of 1.38 (95% CI: 1.33, 1.44). Compared to individuals without multimorbidity and a healthy lifestyle score of 5-6, patients with multimorbidity and a lifestyle score of 0-1 had a significantly higher risk of dementia (HR: 3.13; 95% CI: 2.64, 3.72), but the risk was markedly attenuated among those with multimorbidity and a lifestyle score of 5-6. Among patients with 3 or more diseases, the HR for dementia was 0.53 (95%CI: 0.42, 0.68) when comparing a lifestyle score of 5-6 to 0-1. And we observed more pronounced association between them among people younger than 60 years old. CONCLUSIONS: Adherence to a combination of healthy lifestyle factors, especially at a young age, was associated with a significantly lower risk of dementia among participants with multimorbidity.


Assuntos
Demência , Multimorbidade , Humanos , Estudos Prospectivos , Fatores de Risco , Estilo de Vida , Estilo de Vida Saudável , Demência/epidemiologia , Demência/etiologia
12.
Transl Res ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38494125

RESUMO

Hepatic ischemia reperfusion (I/R) injury is a common clinical complication. X-box binding protein 1 (XBP1), as a critical regulator of the endoplasmic reticulum stress, has been implicated in a variety of diseases. In this study, we aimed to investigate the effects and the underlying mechanism of XBP1 in the progression of hepatic I/R injury. Hepatocyte-specific XBP1 knockout mice, multiple viral delivery systems and specific pharmacological inhibitors were applied in vivo in a partial hepatic I/R injury mouse model and in vitro in a cell model of hypoxia-reoxygenation (H/R) injury. Mitophagy and autophagic flux were evaluated and fluorescence resonance energy transfer (FRET) as well as immunoprecipitation were performed. The results demonstrated that reperfusion for 6 h represented a critical timepoint in hepatic I/R injury and resulted in significant intracellular mitochondrial dysfunction; led to the breakdown of hepatocytes accompanied by the highest expression levels of XBP1. Hepatocyte-specific XBP1 knockout alleviated hepatic I/R injury via enhanced mitophagy, as demonstrated by the reduction in hepatocellular damage/necrosis and increased expression of mitophagy markers. Mechanistically, XBP1 interacted with FoxO1 directly and catalyzed the ubiquitination of FoxO1 for proteasomal degradation. Targeting XBP1 by genetic or pharmacological techniques potentiated the protein levels of FoxO1, further promoting the activity of the PINK1/Parkin signaling pathway, thus augmenting mitophagy and exerting hepatoprotective effects upon I/R injury. In conclusion, the inhibition of XBP1 potentiated FoxO1-mediated mitophagy in hepatic I/R injury. Specific genetic and pharmacological treatment targeting XBP1 in the perioperative 6 h prior to reperfusion exerted beneficial effects, thus providing a novel therapeutic approach.

13.
Cereb Cortex ; 34(3)2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38466117

RESUMO

Speech disorders are associated with different degrees of functional and structural abnormalities. However, the abnormalities associated with specific disorders, and the common abnormalities shown by all disorders, remain unclear. Herein, a meta-analysis was conducted to integrate the results of 70 studies that compared 1843 speech disorder patients (dysarthria, dysphonia, stuttering, and aphasia) to 1950 healthy controls in terms of brain activity, functional connectivity, gray matter, and white matter fractional anisotropy. The analysis revealed that compared to controls, the dysarthria group showed higher activity in the left superior temporal gyrus and lower activity in the left postcentral gyrus. The dysphonia group had higher activity in the right precentral and postcentral gyrus. The stuttering group had higher activity in the right inferior frontal gyrus and lower activity in the left inferior frontal gyrus. The aphasia group showed lower activity in the bilateral anterior cingulate gyrus and left superior frontal gyrus. Across the four disorders, there were concurrent lower activity, gray matter, and fractional anisotropy in motor and auditory cortices, and stronger connectivity between the default mode network and frontoparietal network. These findings enhance our understanding of the neural basis of speech disorders, potentially aiding clinical diagnosis and intervention.


Assuntos
Afasia , Córtex Auditivo , Disfonia , Gagueira , Humanos , Disartria , Funções Verossimilhança , Distúrbios da Fala
14.
Phytomedicine ; 128: 155431, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38537440

RESUMO

BACKGROUND: Non-small cell lung cancer (NSCLC) remains at the forefront of new cancer cases, and there is an urgent need to find new treatments or improve the efficacy of existing therapies. In addition to the application in the field of cerebrovascular diseases, recent studies have revealed that tanshinone IIA (Tan IIA) has anticancer activity in a variety of cancers. PURPOSE: To investigate the potential anticancer mechanism of Tan IIA and its impact on immunotherapy in NSCLC. METHODS: Cytotoxicity and colony formation assays were used to detect the Tan IIA inhibitory effect on NSCLC cells. This research clarified the mechanisms of Tan IIA in anti-tumor and programmed death-ligand 1 (PD-L1) regulation by using flow cytometry, transient transfection, western blotting and immunohistochemistry (IHC) methods. Besides, IHC was also used to analyze the nuclear factor of activated T cells 1 (NFAT2) expression in NSCLC clinical samples. Two animal models including xenograft mouse model and Lewis lung cancer model were used for evaluating tumor suppressive efficacy of Tan IIA. We also tested the efficacy of Tan IIA combined with programmed cell death protein 1 (PD-1) inhibitors in Lewis lung cancer model. RESULTS: Tan IIA exhibited good NSCLC inhibitory effect which was accompanied by endoplasmic reticulum (ER) stress response and increasing Ca2+ levels. Moreover, Tan IIA could suppress the NFAT2/ Myc proto oncogene protein (c-Myc) signaling, and it also was able to control the Jun Proto-Oncogene(c-Jun)/PD-L1 axis in NSCLC cells through the c-Jun N-terminal kinase (JNK) pathway. High NFAT2 levels were potential factors for poor prognosis in NSCLC patients. Finally, animal experiments data showed a stronger immune activation phenotype, when we performed treatment of Tan IIA combined with PD-1 monoclonal antibody. CONCLUSION: The findings of our research suggested a novel mechanism for Tan IIA to inhibit NSCLC, which could exert anti-cancer effects through the JNK/NFAT2/c-Myc pathway. Furthermore, Tan IIA could regulate tumor PD-L1 levels and has the potential to improve the efficacy of PD-1 inhibitors.

15.
Adv Mater ; : e2400648, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488330

RESUMO

The increasingly severe plastic pollution has urged an inevitable trend to develop biodegradable plastic products that can take over synthetic plastics. As one of the most abundant natural polymers, polysaccharides are an ideal candidate to substitute synthetic plastics. The rigidity of polysaccharide chains principally allows for high strength and stiffness of their materials, however, challenges the facile orientation in material processing. Here, a general hydrogen bond-mediated plasticization strategy to regulate isotropic sodium alginate (SA) chains to a highly ordered state is developed, and alginate plastics with high performances are fabricated. It is revealed that hydroxyl groups in glycerol modulate the viscoelasticity of SA solids by forming strong hydrogen bonds with SA chains, achieving a large stretchability at a high solid content. Highly orientated alginate films exhibit a superior tensile strength of 575 MPa and toughness of 60.7 MJ m-3, outperforming most regenerated biomass films. The high solid content and large stretchability mediated by strong hydrogen bonding ensure plastic molding of solid-like SA with high fidelity. This hydrogen bond-mediated plasticity provides a facile but effective method to justify the high performances of polysaccharide-based plastics.

16.
Front Med (Lausanne) ; 11: 1342344, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38449887

RESUMO

Background: Whether sarcopenic obesity had unfavorable effect on survival of peritoneal dialysis (PD) patients is unknown. We aimed to investigate the association between sarcopenic obesity and survival in PD patients. Methods: This was a prospective observational study. Eligible PD patients from November 2016 to December 2017 were enrolled and followed until August 31, 2023. Sarcopenia was defined following the recommendations of the Asian Working Group for Sarcopenia (AWGS) as low appendicular skeletal muscle mass index (ASMI) and handgrip strength (HGS). Obesity was defined using the percentage of body fat (PBF). Survival analysis was conducted using the Kaplan-Meier and log-rank test. The Cox regression and the cumulative incidence competing risk (CICR) analyzes were used to investigate the association between sarcopenic obesity and all-cause mortality. Results: A total of 223 patients were enrolled with 133 (59.6%) males, a median age of 57.5 (44.6, 65.7) years, a median dialysis vintage of 20.3 (6.4, 57.7) months and 48 (21.5%) who had comorbid diabetes mellitus. Among them, 46 (20.6%) patients were sarcopenic, and 25 (11.2%) patients were diagnosed with sarcopenic obesity. After followed up for 51.6 (25.6, 73.9) months, the Kaplan-Meier curve showed the sarcopenic obesity (log-rank = 13.527, p < 0.001) group had significant lower survival rate compared to the nonsarcopenic non-obesity group. For multivariate analysis, the CICR method showed patients with sarcopenic obesity had significantly higher mortality rate (HR: 2.190, 95% CI: 1.011-4.743, p = 0.047) compared to those with nonsarcopenic non-obesity. Conclusion: Sarcopenia is not uncommon in PD patients, with a considerable proportion having sarcopenic obesity. There is a significant association between sarcopenic obesity and an increased risk of mortality in PD patients.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38466070

RESUMO

Context: In the context of ulcerative coloproctitis (UC), a chronic and non-specific inflammatory condition of the colon and rectum with an elusive etiology, the therapeutic potential of G protein-coupled receptor 109a (GPR109a) has gained prominence. GPR109a is expressed in various cell types including colonic epithelium, adipocytes, neutrophils, and macrophages, positioning it as a promising candidate for pharmacological intervention in colitis. Objective: the mechanistic role of GPR109a in a mouse model of UC and to assess its capacity to mitigate the disease's progression. Design: The research team performed an animal study. Setting: Conducted by a research team in the biomedical setting of the People's Hospital of Dongxihu District in Wuhan, Hubei province of China. Animals: This animal study engaged 16 specific pathogen-free (SPF) male BALB/c mice, aged between 4 to 6 weeks and weighing 20-24 grams each. Outcome Measures: (1) analysis of rectal lesions via hematoxylin-eosin (HE) staining, (2) the use of transmission electron microscopy to examine suborganelle spatial relationships, (3) Western blot analysis to evaluate a spectrum of protein expressions such as phosphorylated IP3R, p-PERK, p-IRE-1α, mitofusins, NADPH oxidases, TNF-α, and IL-1ß, and (4) determination of intracellular calcium concentrations to gauge intestinal barrier function impairment involving specific calcium pathway signals. Results: Results from the study painted a picture of significant infiltration by inflammatory cells within the mucosal and submucosal layers, compounded by pronounced endoplasmic reticulum expansion. Abundant interfaces between the ER and the mitochondria formed multiple structures known as mitochondria-associated membranes or MAMs. When evaluated under calcium-rich conditions, the protein levels mentioned earlier were notably elevated in the GPR109a knockdown (KD) group versus the infection control (NC) counterparts. However, this differential expression disappeared under calcium-depleted conditions or when treated with 2-aminoethyl diphenyl borinate (2-APB). Additionally, fluorescence intensity assays showed marked suppression in the GPR109a-KD plus lipopolysaccharide (LPS) group compared to the control. Conclusions: Drawing these observations to a close, the study concluded that GPR109a has an inhibitory effect on the advancement of ulcerative coloproctitis in mice. This is mediated through the activation of a calcium-induced oxidative stress cascade within macrophages, delineating a promising therapeutic pathway for the management of this inflammatory disease.

18.
Acta Pharmacol Sin ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438580

RESUMO

Telomere repeat binding factor 2 (TRF2), a critical element of the shelterin complex, plays a vital role in the maintenance of genome integrity. TRF2 overexpression is found in a wide range of malignant cancers, whereas its down-regulation could cause cell death. Despite its potential role, the selectively small-molecule inhibitors of TRF2 and its therapeutic effects on liver cancer remain largely unknown. Our clinical data combined with bioinformatic analysis demonstrated that TRF2 is overexpressed in liver cancer and that high expression is associated with poor prognosis. Flavokavain B derivative FKB04 potently inhibited TRF2 expression in liver cancer cells while having limited effects on the other five shelterin subunits. Moreover, FKB04 treatment induced telomere shortening and increased the amounts of telomere-free ends, leading to the destruction of T-loop structure. Consequently, FKB04 promoted liver cancer cell senescence without modulating apoptosis levels. In corroboration with these findings, FKB04 inhibited tumor cell growth by promoting telomeric TRF2 deficiency-induced telomere shortening in a mouse xenograft tumor model, with no obvious side effects. These results demonstrate that TRF2 is a potential therapeutic target for liver cancer and suggest that FKB04 may be a selective small-molecule inhibitor of TRF2, showing promise in the treatment of liver cancer.

19.
Opt Express ; 32(4): 6748-6764, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439373

RESUMO

Data rate and security are essential performance metrics for passive optical networks (PON). However, existing optical access networks lack standardized metrics to evaluate rate and security performance uniformly. This paper introduces a high-speed and security joint optimization scheme for optical access networks using convex optimization. Evaluation metrics for data rate and security performance in PON are established. According to the evaluation metrics, the security optimization objective function Us, high-speed optimization objective function GMI, and high-speed security joint-optimization objective function Hs are established. An optimization problem is formulated to maximize weighted rate and security indicators, factoring in constraints such as maximum power, probability, amplifier capacity, normalized mutual information, and key and frame lengths. An alternating optimization method is applied to iteratively address sub-problems by exploiting successive convex approximations and differences of convex functions. This transforms non-convex sub-problems into convex optimizations. Experimental results highlight notable improvements in objective function values, confirming the effectiveness of the proposed high-speed security optimization algorithm for optical access networks.

20.
Neuroscience ; 544: 117-127, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38447688

RESUMO

Previous research has mapped out the brain regions that respond to semantic stimuli presented visually and auditorily, but there is debate about whether semantic representation is modality-specific (only written or only spoken) or modality-invariant (both written and spoken). The mechanism of semantic representation underlying native (L1) and second language (L2) comprehension in different modalities as well as how this mechanism is influenced by L2 proficiency, remains unclear. We used functional magnetic resonance imaging (fMRI) data from the OpenNEURO database to calculate neural pattern similarity across native and second languages (Spanish and English) for different input modalities (written and spoken) and learning sessions (before and after training). The correlations between behavioral performance and cross-language pattern similarity for L1 and L2 were also calculated. Spanish-English bilingual adolescents (N = 24; ages 16-17; 19 girls) participated in a 3-month English immersion after-school program. As L2 proficiency increased, greater cross-language pattern similarity between L1 and L2 spoken words was observed in the left pars triangularis. Cross-language pattern similarity between L1 and L2 written words was observed in the right anterior temporal lobe. Brain-behavior correlations indicated that increased cross-language pattern similarity between L1 and L2 written words in the right anterior temporal lobe was associated with L2 written word comprehension. This study identified an effective neurofunctional predictor related to L2 written word comprehension.


Assuntos
Multilinguismo , Feminino , Adolescente , Humanos , Idioma , Semântica , Encéfalo/diagnóstico por imagem , Língua
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