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1.
Artigo em Inglês | MEDLINE | ID: mdl-38646899

RESUMO

INTRODUCTION: The phosphatidylinositol-3-kinase (PI3K) pathway is a crucial intracellular signaling pathway involved in cell growth, proliferation, survival, and metabolism, which is aberrant in almost all types of cancer. Extensive research is dedicated to elucidating the mechanisms of action and developing PI3K inhibitors. However, only a small portion of the research has been successfully translated into clinical applications. AREAS COVERED: In this review, we present an overview of the pivotal role that the PI3K pathway plays in tumor development. We discuss the current landscape of PI3K inhibitors in preclinical and clinical trials, address the mechanisms of resistance to PI3K inhibition along with their associated toxic effects, and highlight significant advancements in preclinical research of this field. EXPERT OPINION: Based on our study and comprehension of PI3K, we provide a recapitulation of the key lessons learned from the research process and propose potential measures for improvement that could prove valuable.

2.
J Cell Mol Med ; 28(8): e18270, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38568081

RESUMO

The objective of this study was to examine the association between the serum copper concentration and the prevalence of diabetes among US adults with hypertension using the data from the National Health and Nutrition Examination Survey (NHANES). The study population was selected from adults aged over 20 years old in the three survey cycles of NHANES from 2011 to 2016. Logistic regression model analyses were applied to determine the independent risky effect of copper to the prevalence of diabetes. Also, a restricted cubic spline (RCS) model was performed to explore the potential nonlinear association between serum copper concentration and the prevalence of diabetes. A total of 1786 subjects (742 cases and 1044 controls) were included, and 924 were men (51.7%), and 742 (41.5%) were diabetic. Compared with non-diabetic individuals, the concentration of serum copper in diabetic patients with hypertension was higher. After adjusting for age, sex, race, education, marital status, body mass index (BMI), family poverty income ratio (PIR), smoking, alcohol drinking, physical activity, systolic blood pressure (SBP), diastolic blood pressure (DBP), and hyperlipidemia, the highest quartile of serum copper concentration significantly increased the risk of diabetes as compared with the lowest quartile (OR: 1.38, 95% CI: 1.01-1.92, ptrend = 0.036). The results of RCS analysis showed significant non-linear relationship between serum copper concentration and prevalence of diabetes (p-non-linear = 0.010). This study finds that serum copper concentration are significantly associated with risk of diabetes in hypertensive patients, which suggests copper as an important risk factor of diabetes development.


Assuntos
Diabetes Mellitus , Hipertensão , Adulto , Masculino , Humanos , Feminino , Inquéritos Nutricionais , Cobre , Prevalência , Diabetes Mellitus/epidemiologia , Hipertensão/epidemiologia
3.
BMC Cardiovasc Disord ; 24(1): 191, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570824

RESUMO

AIM: To examine the prognostic value of superoxide dismutase (SOD) activity for monitoring reduced left ventricular ejection fraction(LVEF)in the patients with type 2 diabetes and acute coronary syndrome (ACS). METHODS: The population of this cross-sectional study included 2377 inpatients with type 2 diabetes who had an ACS admitted to the Shandong Provincial Hospital Affiliated to Shandong First Medical University from January 2016 to January 2021. RESULTS: Diabetic patients with ACS were divided into 2 subgroups based on LVEF. The mean SOD activity was significantly lower in patients with an LVEF ≤ 45% than in those with an LVEF > 45% (149.1 (146.4, 151.9) versus 161.9 (160.8, 163.0)). Using ROC statistic, a cut-off value of 148.8 U/ml indicated an LVEF ≤ 45% with a sensitivity of 51.6% and a specificity of 73.7%. SODs activity were found to be correlated with the levels of NT-proBNP, hs-cTnT, the inflammatory marker CRP and fibrinogen. Despite taking the lowest quartile as a reference (OR 0.368, 95% CI 0.493-0.825, P = 0.001) or examining 1 normalized unit increase (OR 0.651, 95% CI 0.482-0.880, P = 0.005), SOD activity was found to be a stronger predictor of reduced LVEF than CRP and fibrinogen, independent of confounding factors. CONCLUSIONS: Our cross-sectional study suggests that SOD activity might be a valuable and easily accessible tool for assessing and monitoring reduced LVEF in the diabetic patients with ACS.


Assuntos
Síndrome Coronariana Aguda , Diabetes Mellitus Tipo 2 , Disfunção Ventricular Esquerda , Humanos , Síndrome Coronariana Aguda/diagnóstico , Volume Sistólico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Biomarcadores , Estudos Transversais , Função Ventricular Esquerda , Disfunção Ventricular Esquerda/epidemiologia , Prognóstico , Superóxido Dismutase , Fibrinogênio
4.
Acad Radiol ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38653597

RESUMO

RATIONALE AND OBJECTIVES: To explore the feasibility of delta histogram parameters (including absolute delta histogram parameters (AdHP) and relative delta histogram parameters (RdHP)) in predicting the grade of meningioma and to further investigate whether delta histogram parameters correlate with the Ki-67 proliferation index. METHODS: 92 patients with meningioma who underwent MRI examination (including T1-weighted (T1) and contrast-enhanced T1-weighted images (T1C)) were enrolled in this retrospective study. A total of 46 low-grade cases formed the low-grade group (grade 1, LGM), and a total of 46 high-grade cases formed the high-grade group (38 grade 2, 8 grade 3, HGM). Histogram parameters (HP) of T1 and T1C were extracted. Subsequently, morphological MRI features, AdHP (AdHP=T1CHP-T1HP), and RdHP (RdHP=(T1CHP-T1HP)/T1HP) were recorded and compared, respectively. Binary logistic regression analysis was used to obtain combined performance of the significant parameters. Diagnostic performance was identified by ROC. Spearman's correlation coefficients were taken to assess the relationship between delta histogram parameters and the Ki-67 proliferation index. RESULTS: In morphological MRI features, HGM is more prone to lobulation and necrosis/cystic changes (all p < 0.05). In delta histogram parameters, HGM exhibits higher mean, Perc.01, Perc.25, Perc.50, Perc.75, Perc.99, SD, and variance of AdHP, maximum, mean, Perc.25, Perc.50, Perc.75, and Perc.99 of RdHP, compared to LGM (all p < 0.00357). The optimal predictive performance was obtained by combining morphological MRI features and delta histogram parameters with an AUC of 0.945. Significant correlations were observed between significant delta histogram parameters and the Ki-67 proliferation index (all p < 0.05). CONCLUSION: Delta histogram parameter is a promising potential biomarker, which may be helpful in noninvasive predicting the grade and proliferative activity of meningioma.

5.
J Med Chem ; 67(8): 6425-6455, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38613499

RESUMO

The RAS-RAF-MEK-ERK signaling cascade is abnormally activated in various tumors, playing a crucial role in mediating tumor progression. As the key component at the terminal stage of this cascade, ERK1/2 emerges as a potential antitumor target and offers a promising therapeutic strategy for tumors harboring BRAF or RAS mutations. Here, we identified 36c with a (thiophen-3-yl)aminopyrimidine scaffold as a potent ERK1/2 inhibitor through structure-guided optimization for hit 18. In preclinical studies, 36c showed powerful ERK1/2 inhibitory activities (ERK1/2 IC50 = 0.11/0.08 nM) and potent antitumor efficacy both in vitro and in vivo against triple-negative breast cancer and colorectal cancer models harboring BRAF and RAS mutations. 36c could directly inhibit ERK1/2, significantly block the phosphorylation expression of their downstream substrates p90RSK and c-Myc, and induce cell apoptosis and incomplete autophagy-related cell death. Taken together, this work provides a promising ERK1/2 lead compound for multiple tumor-treatment drug discovery.


Assuntos
Antineoplásicos , Inibidores de Proteínas Quinases , Pirimidinas , Humanos , Pirimidinas/farmacologia , Pirimidinas/síntese química , Pirimidinas/química , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/síntese química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Relação Estrutura-Atividade , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Tiofenos/farmacologia , Tiofenos/síntese química , Tiofenos/química , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Linhagem Celular Tumoral , Descoberta de Drogas , Apoptose/efeitos dos fármacos , Feminino , Camundongos Nus , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Endogâmicos BALB C
6.
Int Immunopharmacol ; 133: 112066, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615377

RESUMO

Acevaltrate is a natural product isolated from the roots of Valeriana glechomifolia F.G.Mey. (Valerianaceae) and has been shown to exhibit anti-cancer activity. However, the mechanism by which acevaltrate inhibits tumor growth is not fully understood. We here demonstrated the effect of acevaltrate on hypoxia-inducible factor-1α (HIF-1α) expression. Acevaltrate showed a potent inhibitory activity against HIF-1α induced by hypoxia in various cancer cells. This compound markedly decreased the hypoxia-induced accumulation of HIF-1α protein dose-dependently. Further analysis revealed that acevaltrate inhibited HIF-1α protein synthesis and promoted degradation of HIF-1α protein, without affecting the expression level of HIF-1α mRNA. Moreover, the phosphorylation levels of mammalian target of rapamycin (mTOR), ribosomal protein S6 kinase (p70S6K), and eIF4E binding protein-1 (4E-BP1) were significantly suppressed by acevaltrate. In addition, acevaltrate promoted apoptosis and inhibited proliferation, which was potentially mediated by suppression of HIF-1α. We also found that acevaltrate administration inhibited tumor growth in mouse xenograft model. Taken together, these results suggested that acevaltrate was a potent inhibitor of HIF-1α and provided a new insight into the mechanisms of acevaltrate against cancers.

7.
Eur J Radiol ; 175: 111444, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38531223

RESUMO

OBJECTIVE: To assess the prognostic value of pre- and post-therapeutic changes in extracellular volume (ECV) fraction of liver metastases (LMs) for treatment response (TR) and survival outcomes in colorectal cancer liver metastases (CRLM). METHODS: 186 LMs were confirmed by pathology or follow-up (Training: 130; Test: 56). We analyzed the changes in ECV fraction of LMs before and after 2 cycles of chemotherapy combined with bevacizumab. After 12 cycles, we evaluated the TR on LMs based on the RECIST v1.1. Relative changes in ECV fraction and Hounsfield Units (HU), defined as ΔECV and ΔHU, were associated with progression-free survival (PFS), overall survival (OS), and TR. We identified TR predictors with multivariate logistic regression and PFS, OS risk factors with COX analysis. RESULTS: 186 LMs were classified as TR lesions (TR+: 84) and non-TR lesions (TR-:102). ΔECV, ΔHUA-E, and texture could distinguish the TR of LMs in training and test set (P < 0.05). ΔECV [Odds ratio (OR): 1.03; 95% Confidence interval (CI): 1.02-1.05, P < 0.01] was an independent predictor of TR-. Area under the curve (AUC), sensitivity and specificity of TR model in training and test set were 0.87, 0.84, 90.14%, 90.32%, 72.88%, 64.00%, respectively. High CRD_score indicates that patients have shorter PFS [Hazard ratio (HR): 2.01; 95%CI: 1.02-3.98, P = 0.045)] and OS (HR: 1.89, 95%CI: 1.04-3.42, P = 0.038). CONCLUSION: ΔECV can be used as an independent predictor of TR of CRLM chemotherapy combined with bevacizumab.

8.
Lancet Digit Health ; 6(4): e261-e271, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519154

RESUMO

BACKGROUND: Artificial intelligence (AI) models in real-world implementation are scarce. Our study aimed to develop a CT angiography (CTA)-based AI model for intracranial aneurysm detection, assess how it helps clinicians improve diagnostic performance, and validate its application in real-world clinical implementation. METHODS: We developed a deep-learning model using 16 546 head and neck CTA examination images from 14 517 patients at eight Chinese hospitals. Using an adapted, stepwise implementation and evaluation, 120 certified clinicians from 15 geographically different hospitals were recruited. Initially, the AI model was externally validated with images of 900 digital subtraction angiography-verified CTA cases (examinations) and compared with the performance of 24 clinicians who each viewed 300 of these cases (stage 1). Next, as a further external validation a multi-reader multi-case study enrolled 48 clinicians to individually review 298 digital subtraction angiography-verified CTA cases (stage 2). The clinicians reviewed each CTA examination twice (ie, with and without the AI model), separated by a 4-week washout period. Then, a randomised open-label comparison study enrolled 48 clinicians to assess the acceptance and performance of this AI model (stage 3). Finally, the model was prospectively deployed and validated in 1562 real-world clinical CTA cases. FINDINGS: The AI model in the internal dataset achieved a patient-level diagnostic sensitivity of 0·957 (95% CI 0·939-0·971) and a higher patient-level diagnostic sensitivity than clinicians (0·943 [0·921-0·961] vs 0·658 [0·644-0·672]; p<0·0001) in the external dataset. In the multi-reader multi-case study, the AI-assisted strategy improved clinicians' diagnostic performance both on a per-patient basis (the area under the receiver operating characteristic curves [AUCs]; 0·795 [0·761-0·830] without AI vs 0·878 [0·850-0·906] with AI; p<0·0001) and a per-aneurysm basis (the area under the weighted alternative free-response receiver operating characteristic curves; 0·765 [0·732-0·799] vs 0·865 [0·839-0·891]; p<0·0001). Reading time decreased with the aid of the AI model (87·5 s vs 82·7 s, p<0·0001). In the randomised open-label comparison study, clinicians in the AI-assisted group had a high acceptance of the AI model (92·6% adoption rate), and a higher AUC when compared with the control group (0·858 [95% CI 0·850-0·866] vs 0·789 [0·780-0·799]; p<0·0001). In the prospective study, the AI model had a 0·51% (8/1570) error rate due to poor-quality CTA images and recognition failure. The model had a high negative predictive value of 0·998 (0·994-1·000) and significantly improved the diagnostic performance of clinicians; AUC improved from 0·787 (95% CI 0·766-0·808) to 0·909 (0·894-0·923; p<0·0001) and patient-level sensitivity improved from 0·590 (0·511-0·666) to 0·825 (0·759-0·880; p<0·0001). INTERPRETATION: This AI model demonstrated strong clinical potential for intracranial aneurysm detection with improved clinician diagnostic performance, high acceptance, and practical implementation in real-world clinical cases. FUNDING: National Natural Science Foundation of China. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Aprendizado Profundo , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Inteligência Artificial , Estudos Prospectivos , Angiografia Cerebral/métodos
9.
Neuroradiology ; 66(4): 531-541, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38400953

RESUMO

PURPOSE: To investigate the value of histogram analysis of postcontrast T1-weighted (T1C) and apparent diffusion coefficient (ADC) images in predicting the grade and proliferative activity of adult intracranial ependymomas. METHODS: Forty-seven adult intracranial ependymomas were enrolled and underwent histogram parameters extraction (including minimum, maximum, mean, 1st percentile (Perc.01), Perc.05, Perc.10, Perc.25, Perc.50, Perc.75, Perc.90, Perc.95, Perc.99, standard deviation (SD), variance, coefficient of variation (CV), skewness, kurtosis, and entropy of T1C and ADC) using FireVoxel software. Differences in histogram parameters between grade 2 and grade 3 adult intracranial ependymomas were compared. Receiver operating characteristic curves and logistic regression analyses were conducted to evaluate the diagnostic performance. Spearman's correlation analysis was used to evaluate the relationship between histogram parameters and Ki-67 proliferation index. RESULTS: Grade 3 intracranial ependymomas group showed significantly higher Perc.95, Perc.99, SD, variance, CV, and entropy of T1C; lower minimum, mean, Perc.01, Perc.05, Perc.10, Perc.25, Perc.50 of ADC; and higher CV and entropy of ADC than grade 2 intracranial ependymomas group (all p < 0.05). Entropy (T1C) and Perc.10 (ADC) had a higher diagnostic performance with AUCs of 0.805 and 0.827 among the histogram parameters of T1C and ADC, respectively. The diagnostic performance was improved by combining entropy (T1C) and Perc.10 (ADC), with an AUC of 0.857. Significant correlations were observed between significant histogram parameters of T1C (r = 0.296-0.417, p = 0.001-0.044) and ADC (r = -0.428-0.395, p = 0.003-0.038). CONCLUSION: Whole-tumor histogram analysis of T1C and ADC may be a promising approach for predicting the grade and proliferative activity of adult intracranial ependymomas.


Assuntos
Neoplasias Encefálicas , Ependimoma , Adulto , Humanos , Imagem de Difusão por Ressonância Magnética/métodos , Curva ROC , Neoplasias Encefálicas/patologia , Estudos Retrospectivos
10.
Heliyon ; 10(3): e25316, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38352755

RESUMO

Objectives: The correlation between exercise type and intensity and coronary artery inflammation in patients with stable coronary artery disease (CAD) is unknown. Therefore, this study assessed the relationship between coronary inflammation quantified by coronary computed tomography angiography (CCTA) and exercise intensity and pattern in patients with CAD. Materials and methods: Patients who underwent CCTA between 2019 and 2023 in the second hospital of Lanzhou University were retrospectively examined. We calculated the pericoronary fat attenuation index (FAI) on the right coronary artery (RCA) as a marker of coronary inflammation. We compared basic information, exercise status, and RCA-FAI values between the two groups, and described the relationship between different exercise durations and RCA-FAI using analysis of variance and restricted cubic splines. Results: In total, 1222 patients were included: 774 had no CAD and 448 patients had CAD. Sex (P = 0.016; odds ratio [OR]: 0.673), high-density lipoprotein (P = 0.006; OR: 0.601), low-density lipoprotein (P = 0.001; OR. 0.762), hypertension (P = 0.000; OR: 0.762), smoking (P = 0.005; OR: 0.670), and postprandial glucose (P = 0.030; OR: 0.812), household income (P = 0.038; OR:1.117), and body mass index (P = 0.000; OR:1.084) were the risk factors for elevated RCA-FAI values in the patients with coronary artery disease group. And when the exercise modality was running and aerobics, the correlation between RCA-FAI values and exercise time showed a "U"-shaped relationship. Follow-up revealed that short periods of high-intensity exercise resulted in lower RCA-FAI values. Conclusion: RCA-FAI was significantly associated with coronary artery inflammation. Although appropriate physical activity reduced the risk of pericoronary inflammation and coronary atherosclerosis, overly prolonged exercise could exacerbate the coronary inflammatory response and increase the likelihood of CAD.

12.
Sci Rep ; 14(1): 4801, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413783

RESUMO

An innovative energy-absorbing and bearing structure was proposed, which incorporated the coupling of glass microspheres with a metal tube. Glass microsphere-filled steel tube (GMFST) column, consisting of external steel tube and inner glass microspheres, was expected to give full play to the energy-absorbing and load-bearing capacities of the particle while restricting particle flow from collapsing, thereby enhancing the overall structural strength. Four groups of steel tubes and the GMFST specimens were designed and subjected to axial compression tests at four different loading rates to investigate the performance of the structure. These tests aimed to analyze the deformation mode, mechanical response, and energy absorption capacity of the GMFST columns under quasi-static to low-speed compression conditions. The results indicated that the deformation process and failure mode of GMFST columns were similar to those of hollow steel tubes, albeit with a different post-buckling mode. Filling the steel tubes with glass microspheres reduced the load fluctuation range, moderated load-displacement curves, and exhibited a strain rate strengthening effect. The GMFST columns demonstrated superior energy absorption capacity, with significant increases in crush force efficiency, the averaged crush force, and the total absorbed energy, particularly in terms of subsequent support capacity. The load-increasing reinforcement properties enabled GMFST columns to overcome the limitations associated with the unstable post-buckling path of energy­absorbing damping structure, exhibiting outstanding load-bearing performance and stability in the later stages. The results provided valuable guidelines for designing and engineering high-performance GMFST columns, serving as a new type of energy-absorbing and supporting structure.

14.
Biomed Pharmacother ; 171: 116161, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244330

RESUMO

Autoimmune hepatitis (AIH) is a progressive liver disease mediated by the immune system that involves an imbalance in pro-inflammatory and regulatory mechanisms including regulatory T cells (Tregs), T helper 17 (Th17) cells, Th1, macrophages, and many other immune cells. Current steroid therapy for AIH has significant systemic side effects and is poorly tolerated by some individuals. Therefore, there is an urgent need for alternative treatments. Maintaining homeostasis in macrophage differentiation and activation is crucial for regulating immune responses in hepatitis. In this study, we loaded small interfering RNA (siRNA) targeting receptor-interacting protein kinase 3 (RIPK3) into M2-type macrophage-derived exosomes (M2 Exos) to create functionalized exosomes called M2 Exos/siRIPK3. These exosomes demonstrated a natural ability to target the liver in mice, as they were efficiently taken up by hepatic macrophages and showed significant and stable accumulation. M2 Exos/siRIPK3 effectively mitigated immune-mediated hepatitis by suppressing the expression of RIPK3, resulting in a reduced release of pro-inflammatory cytokines and chemokines in both liver tissues and serum. Additionally, M2 Exos/siRIPK3 exhibited immunomodulatory effects, as its administration resulted in a decreased proportion of hepatic and splenic Th17 cells, along with an increased ratio of Tregs. Overall, this study suggests that loading small molecule drugs onto M2 Exos could be a promising approach for developing immunomodulators that specifically target liver macrophages to treat AIH. This strategy has the potential to provide a safer and more effective alternative to current therapy for AIH patients.


Assuntos
Exossomos , Hepatite Autoimune , Humanos , Animais , Camundongos , Exossomos/metabolismo , Macrófagos/metabolismo , Citocinas/metabolismo , RNA Interferente Pequeno/metabolismo , Imunoterapia
15.
Chemistry ; 30(11): e202303701, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38078510

RESUMO

Pyramidane molecules have attracted chemists for many decades due to their regular shape, high symmetry and their correspondence in the macroscopic world. Recently, experimental access to a number of examples has been reported, in particular the rarely reported square pyramidal bora[4]pyramidanes. To describe the bonding situation of the nonclassical structure of pyramidanes, we present solid-state Nuclear Magnetic Resonance (NMR) as a versatile tool for deciphering such bonding properties for three now accessible bora[4]pyramidane and dibora[5]pyramidane molecules. 11 B solid-state NMR spectra indicate that the apical boron nuclei in these compounds are strongly shielded (around -50 ppm vs. BF3 -Et2 O complex) and possess quadrupolar coupling constants of less than 0.9 MHz pointing to a rather high local symmetry. 13 C-11 B spin-spin coupling constants have been explored as a measure of the bond covalency in the borapyramidanes. While the carbon-boron bond to the -B(C6 F5 )2 substituents of the base serves as an example for a classical covalent 2-center-2-electron (2c-2e) sp2 -carbon-sp2 -boron σ-bond with 1 J(13 C-11 B) coupling constants in the order of 75 Hz, those of the boron(apical)-carbon(basal) bonds in the pyramid are too small to measure. These results suggest that these bonds have a strongly ionic character, which is also supported by quantum-chemical calculations.

16.
Angew Chem Int Ed Engl ; 63(10): e202318283, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38153170

RESUMO

Mesoionic polarization allows access to electron-rich olefins that have found application as organocatalysts, ligands, or nucleophiles. Herein, we report the synthesis and characterization of a series of 3-methylpyridinium-derived mesoionic olefins (py-mNHOs). We used a DFT-supported design concept, which showed that the introduction of aryl groups in the 1-, 2-, 4-, and 6-positions of the heterocyclic core allowed the kinetic stabilization of the novel mesoionic compounds. Tolman electronic parameters indicate that py-mNHOs are remarkably strong σ-donor ligands toward transition metals and main group Lewis acids. Additionally, they are among the strongest nucleophiles on the Mayr reactivity scale. In reactions of py-mNHOs with electron-poor π-systems, a gradual transition from the formation of zwitterionic adducts via stepwise to concerted 1,3-dipolar cycloadditions was observed experimentally and analyzed by quantum-chemical calculations.

17.
Sensors (Basel) ; 23(23)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38067978

RESUMO

In this work, a flexible electrochemical sensor was developed for the detection of organophosphorus pesticides (OPs). To fabricate the sensor, graphene was generated in situ by laser-induced graphene (LIG) technology on a flexible substrate of polyimide (PI) film to form a three-electrode array, and pralidoxime (PAM) chloride was used as the probe molecule. CeO2 was used to modify the working electrode to improve the sensitivity of the sensor because of its electrocatalytic effect on the oxidation of PAM, and the Ag/AgCl reference electrode was prepared by the drop coating method. The effects of the laser power, laser scanning speed, and CeO2 modification on the electrochemical properties of the sensor were studied in detail. The results prove that the sensor has good repeatability, stability, and anti-interference ability, and it shows an excellent linear response in the chlorpyrifos concentration range from 1.4 × 10-8 M to 1.12 × 10-7 M with the detection limit of 7.01 × 10-10 M.

18.
Lipids Health Dis ; 22(1): 190, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37946249

RESUMO

OBJECTIVE: To investigate the correlation between anthropometric indexes [cardiometabolic index (CMI), lipid accumulation products (LAP), waist triglyceride index (WTI), and body mass index (BMI)] and acute pancreatitis (AP) in a Chinese adult population. METHODOLOGY: The present investigation consisted of a prospective group including 117,326 subjects who were enrolled in the Kailuan investigation. The individuals were categorized into quartiles based on their baseline levels of CMI, LAP, and WIT. BMI was categorized into three distinctive groups: normal weight group (BMI < 24 kg/m2), overweight group (BMI 24-28 kg /m2), and obesity group (BMI ≥ 28 kg/m2). The data were subjected to analysis in order to investigate the correlation between these anthropometric indexes and the incidence of AP. Cox regression models were employed to assess the relative risk of AP while accounting for known risk factors through appropriate adjustments. OUTCOMES: Over the course of a median follow-up duration of 12.59 ± 0.98 years, we documented 401 incident AP cases. Incidence density and cumulative incidence rates of AP increased with the increase of CMI, LAP, and WTI. After multivariate adjustment, the fourth quartile of CMI, LAP, and WTI exhibited the greatest risk of AP [CMI: hazard ratio (HR) 1.93, 95% confidential interval (CI) (1.45-2.57); LAP: HR 2.00, 95% CI(1.49-2.68); WTI: HR 2.13,95% CI (1.59-2.83)]. In comparison to the normal weight group, the obesity group (BMI ≥ 28 kg/m2) had an elevated risk of AP (HR = 1.58, 95% CI: 1.21-2.05). Furthermore, the incremental effect of BMI combined with CMI on the prognostic value of AP was greater than that of BMI alone (the C statistics demonstrated a result of 0.607 versus 0.546; the integrated discrimination improvement revealed a result of 0.321%; net reclassification improvement was 1.975%). CONCLUSION: We found that CMI, LAP, and WTI were positively and independently connected to the risk of AP. Additionally, CMI demonstrates a superior prognostic capacity than other indexes in anticipating AP.


Assuntos
Doenças Cardiovasculares , Produto da Acumulação Lipídica , Pancreatite , Humanos , Adulto , Triglicerídeos , Estudos Prospectivos , Doença Aguda , Pancreatite/epidemiologia , Obesidade/epidemiologia , Fatores de Risco , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , China/epidemiologia
19.
Cell Prolif ; : e13570, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37905494

RESUMO

Lung cancer is the leading global cause of cancer-related death, however, resistance to chemotherapy drugs remains a huge barrier to effective treatment. The elevated recruitment of myeloid derived suppressor cells (MDSCs) to tumour after chemotherapy has been linked to resistance of chemotherapy drugs. Nevertheless, the specific mechanism remains unclear. oxPAPC is a bioactive principal component of minimally modified low-density lipoproteins and regulates inflammatory response. In this work, we found that cisplatin, oxaliplatin and ADM all increased oxPAPC release in tumour. Treating macrophages with oxPAPC in vitro stimulated the secretion of MCP-1 and LTB4, which strongly induced monocytes and neutrophils chemotaxis, respectively. Injection of oxPAPC in vivo significantly upregulated the percentage of MDSCs in tumour microenvironment (TME) of wild-type LL2 tumour-bearing mice, but not CCL2-/- mice and LTB4R-/- mice. Critically, oxPAPC acted as a pro-tumor factor in LL2 tumour model. Indeed, cisplatin increased oxPAPC level in tumour tissues of WT mice, CCL2-/- and LTB4R-/- mice, but caused increased infiltration of Ly6Chigh monocytes and neutrophils only in WT LL2-bearing mice. Collectively, our work demonstrates cisplatin treatment induces an overproduction of oxPAPC and thus recruits MDSCs infiltration to promote the tumour growth through the MCP-1/CCL2 and LTB4/LTB4R pathways, which may restrict the effect of multiple chemotherapy. This provides evidence for a potential strategy to enhance the efficacy of multiple chemotherapeutic drugs in the treatment of lung cancer by targeting oxPAPC.

20.
Phytother Res ; 37(10): 4755-4770, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37846157

RESUMO

Chronic social isolation (SI) stress, which became more prevalent during the COVID-19 pandemic, contributes to abnormal behavior, including mood changes and cognitive impairment. Known as a functional nutrient, betaine has potent antioxidant and anti-inflammatory properties in vivo. However, whether betaine can alleviate the abnormal behavior induced by chronic SI in mice remains unknown. In this study, we investigated the efficacy of betaine in the treatment of behavioral changes and its underlying mechanism. Three-week-old male mice were randomly housed for 8 weeks in either group housing (GH) or SI. The animals were divided into normal saline-treated GH, normal saline-treated SI, and betaine-treated SI groups in the sixth week. The cognitive and depression-like behavior was determined in the eighth week. We found that long-term betaine administration improved cognitive behavior in SI mice but failed to prevent depression-like behavior. Moreover, long-term betaine administration inhibited hippocampal microglia over-activation and polarized microglia toward the M2 phenotype, which effectively inhibited the expression of inflammatory factors in SI mice. Finally, the protective effect of betaine treatment in SI mice might not be due to altered activity of the hypothalamic-pituitary-adrenal axis. Collectively, our findings reveal that betaine can improve SI-induced cognitive impairment, thus providing an alternative natural source for the prevention of memory loss caused by SI or loneliness.


Assuntos
Betaína , Disfunção Cognitiva , Camundongos , Masculino , Animais , Humanos , Betaína/efeitos adversos , Betaína/metabolismo , Microglia , Sistema Hipotálamo-Hipofisário , Pandemias , Solução Salina/efeitos adversos , Solução Salina/metabolismo , Sistema Hipófise-Suprarrenal , Hipocampo , Isolamento Social/psicologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/induzido quimicamente
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