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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124974, 2025 Jan 05.
Article de Anglais | MEDLINE | ID: mdl-39151399

RÉSUMÉ

Alcoholic liver disease (ALD) is a chronic toxic liver injury caused by long-term heavy drinking. Due to the increasing incidence, ALD is becoming one of important medical tasks. Many studies have shown that the main mechanism of liver damage caused by large amounts of alcohol may be related to antioxidant stress. As an important antioxidant, cysteine (Cys) is involved in maintaining the normal redox balance and detoxifying metabolic function of the liver, which may be closely related to the pathogenesis of ALD. Therefore, it is necessary to develop a simple non-invasive method for rapid monitoring of Cys in liver. Thus, a near-infrared (NIR) fluorescent probe DCI-Ac-Cys which undergoes Cys triggered cascade reaction to form coumarin fluorophore is developed. Using the DCI-Ac-Cys, decreased Cys was observed in the liver of ALD mice. Importantly, different levels of Cys were monitored in the livers of ALD mice taking silybin and curcumin with the antioxidant effects, indicating the excellent therapeutic effect on ALD. This study provides the important references for the accurate diagnosis of ALD and the pharmacodynamic evaluation of silybin and curcumin in the treatment of ALD, and support new ideas for the pathogenesis of ALD.


Sujet(s)
Coumarines , Cystéine , Colorants fluorescents , Maladies alcooliques du foie , Animaux , Cystéine/analyse , Cystéine/métabolisme , Coumarines/composition chimique , Colorants fluorescents/composition chimique , Maladies alcooliques du foie/métabolisme , Maladies alcooliques du foie/anatomopathologie , Mâle , Foie/métabolisme , Foie/effets des médicaments et des substances chimiques , Foie/anatomopathologie , Souris , Souris de lignée C57BL , Spectroscopie proche infrarouge/méthodes , Curcumine/pharmacologie , Spectrométrie de fluorescence , Silibinine/pharmacologie , Silibinine/composition chimique
2.
Front Oncol ; 14: 1452282, 2024.
Article de Anglais | MEDLINE | ID: mdl-39314628

RÉSUMÉ

Background: High mobility group box 1 (HMGB1) and indoleamino-2, 3-dioxygenase (IDO) participate in the occurrence and development of esophageal squamous cell carcinoma (ESCC), regulate the tumor immune microenvironment, and are closely related to tumor growth and metastasis. However, the regulatory mechanism of serum HMGB1 and IDO has not been clarified and needs further exploration. Methods: Blood samples of 55 ESCC patients initially hospitalized in the Fourth Hospital of Hebei Medical University from August 2021 to January 2022 were selected as the ESCC group, and relevant clinical data were collected, and blood samples from 40 healthy people during the same period were selected as the control group. Serum HMGB1 and IDO levels were determined by ELISA, and lymphocyte subsets in peripheral blood of all subjects were detected by flow cytometry. The correlation between the expression levels of HMGB1 and IDO in ESCC cells was detected by Western blot. Results: Serum HMGB1 and IDO levels were significantly increased in ESCC patients, and with the progression of ESCC patients, serum HMGB1 and IDO levels were also gradually increased; serum HMGB1 was significantly correlated with IDO; serum HMGB1 and IDO combined with CEA and SCC-Ag were of high value in predicting the clinical progression of ESCC patients; the absolute counts of CD4+CD28+T cells and CD8+CD28+T cells in high HMGB1 group were significantly lower than those in low HMGB1 group, while the percentage of CD4+PD-1+T cells was significantly higher than that in low HMGB1 group; the percentage and absolute counts of CD4+CD28+T cells and the absolute counts of CD8+CD28+T cells in high IDO group were significantly lower than those in the low IDO group, while the percentage of CD8+PD-1+T cells was significantly higher than that in the low IDO group; increased serum HMGB1 and IDO expression levels were closely related to poor prognosis in ESCC patients; and HMGB1 may promote IDO expression by activating NF-κB signaling pathway. Conclusion: Serum HMGB1 and IDO have a synergistic effect, they inhibit immune function and promote tumor progression in ESCC patients, and also lead to poor prognosis.

3.
Heliyon ; 10(18): e37086, 2024 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-39315218

RÉSUMÉ

Background: AGBL2's role in tumorigenesis and cancer progression has been reported in several cancer studies, and it is closely associated with α-tubulin detyrosination. The roles of AGBL2 and α-tubulin detyrosination in renal cell carcinoma (RCC) pathogenesis remain unclear and require further investigation. Methods: In this study, we conducted an analysis of AGBL2 expression differences between renal clear cell carcinoma tissues and normal tissues using data from The Cancer Genome Atlas (TCGA). We performed a comprehensive prognostic analysis of AGBL2 in Kidney Renal Clear Cell Carcinoma (KIRC) using univariate and multivariate Cox regression. Based on the results of the Cox analysis, we constructed a prognostic model to assess its predictive capabilities. Receiver Operating Characteristic (ROC) analysis confirmed the diagnostic value of AGBL2 in renal cancer. We conducted further validation by analyzing cancer tissue samples and renal cancer cell lines, which confirmed the role of AGBL2 in promoting RCC cell proliferation and migration through in vitro experiments. Additionally, we verified the impact of AGBL2's detyrosination on α-tubulin using the tubulin carboxypeptidase (TCP) inhibitor parthenolide. Finally, we performed sequencing analysis on AGBL2 knockdown 786-O cells to investigate the correlation between AGBL2, immune infiltration, and AKT phosphorylation. Moreover, we experimentally demonstrated the enhancing effect of AGBL2 on AKT phosphorylation. Results: TCGA analysis revealed a significant increase in AGBL2 expression in RCC patients, which was correlated with poorer overall survival (OS), disease-specific survival (DSS), and progression-free intervals (PFI). According to the analysis results, we constructed column-line plots to predict the 1-, 3-, and 5-year survival outcomes in RCC patients. Additionally, the calibration plots assessing the model's performance exhibited favorable agreement with the predicted outcomes. And the ROC curves showed that AGBL2 showed good diagnostic performance in KIRC (AUC = 0.836)). Cell phenotyping assays revealed that AGBL2 knockdown in RCC cells significantly inhibited cell proliferation and migration. Conversely, overexpression of AGBL2 resulted in increased cell proliferation and migration in RCC cells. We observed that AGBL2 is predominantly located in the nucleus and can elevate the detyrosination level of α-tubulin in RCC cells. Moreover, the enhancement of RCC cell proliferation and migration by AGBL2 was partially inhibited after treatment with the TCP inhibitor parthenolide. Analysis of the sequencing data revealed that AGBL2 is associated with a diverse array of biological processes, encompassing signal transduction and immune infiltration. Interestingly, AGBL2 expression exhibited a negative correlation with the majority of immune cell infiltrations. Additionally, AGBL2 was found to enhance the phosphorylation of AKT in RCC cells. Conclusion: Our study suggests that AGBL2 fosters RCC cell proliferation and migration by enhancing α-tubulin detyrosination. Moreover, elevated AGBL2 expression increases phosphorylation of AKT in RCC cells.

4.
Ultrasonics ; 145: 107470, 2024 Sep 17.
Article de Anglais | MEDLINE | ID: mdl-39316886

RÉSUMÉ

The low transmission efficiency of ultrasonic waves in waveguides of a high acoustic impedance (referred to as dense materials), due to the impedance mismatch between the background media and the dense materials, poses a significant obstacle to practical applications of high-intensity focused ultrasound (HIFU) such as ultrasound therapy or medical imaging. To address this challenge, we present an inverse optimization scheme for fabrication of novel acoustic meta-lenses, enabling strengthened penetration and enhanced focusing of ultrasonic waves when the waves traverse barriers. Both simulation and experiment validate the effectiveness of the developed meta-lenses which are annexed to hemispherical plates, and demonstrate an enhanced transmission of the sound power by an order of magnitude compared to a scenario without the use of the meta-lens. The focal distance is reconfigurable by adjusting the geometric parameters of the meta-lenses. The proposed design philosophy is not restricted by the complexity of the target structures, and it allows the ultrasonic waves to pass through acoustic barriers with a non-uniform thickness yet maintaining efficient wave focusing. This study holds appealing applications in HIFU-enabled ultrasound imaging and therapy.

5.
World J Clin Cases ; 12(26): 5937-5945, 2024 Sep 16.
Article de Anglais | MEDLINE | ID: mdl-39286378

RÉSUMÉ

BACKGROUND: Although there is currently a wealth of evidence to indicate that maternal educational attainment is associated with gestational diabetes mellitus (GDM), the specific modifiable risk factors that mediate the causal relationship between these two variables have yet to be identified. AIM: To identify the specific modifiable risk factors that mediate the causal relationship between the level of maternal education and GDM. METHODS: Mendelian randomization (MR) was conducted using data from genome-wide association studies of European populations. We initially performed a two-sample MR analysis using data on genetic variants associated with the duration of education as instruments, and subsequently adopted a two-step MR approach using metabolic and lifestyle factors as mediators to examine the mechanisms underlying the relationship between the level of maternal education and risk of developing GDM. In addition, we calculated the proportions of total causal effects mediated by identified metabolic and lifestyle factors. RESULTS: A genetically predicted higher educational attainment was found to be associated with a lower risk of developing GDM (OR: 0.71, 95%CI: 0.60-0.84). Among the metabolic factors assessed, four emerged as potential mediators of the education-GDM association, which, ranked by mediated proportions, were as follows: Waist-to-hip-ratio (31.56%, 95%CI: 12.38%-50.70%), body mass index (19.20%, 95%CI: 12.03%-26.42%), high-density lipoprotein cholesterol (12.81%, 95%CI: 8.65%-17.05%), and apolipoprotein A-1 (7.70%, 95%CI: 4.32%-11.05%). These findings proved to be robust to sensitivity analyses. CONCLUSION: Our findings indicate a causal relationship between lower levels of maternal education and the risk of developing GDM can be partly explained by adverse metabolic profiles.

6.
Plant Physiol Biochem ; 216: 109127, 2024 Sep 13.
Article de Anglais | MEDLINE | ID: mdl-39284252

RÉSUMÉ

Rising atmospheric carbon dioxide (CO2) and soil heavy metal pollution affect crop safety and production. Exposure to elevated CO2 (ECO2) increases cadmium (Cd) uptake in some crops like wheat and rice, however, it remains unclear how ECO2 affects Cd uptake by Brassica napus. Here, we investigated the responses of B. napus seedlings exposed to ECO2 and Cd through analyses of physiology, transcriptome, metabolome, and rhizosphere microbes. Compared with Cd-stress alone (Cd50_ACO2), ECO2 boosted the uptake of Cd by B. napus roots by 38.78% under coupled stresses (Cd50_ECO2). The biomass and leaf chlorophyll a content increased by 38.49% and 79.66% respectively in Cd50_ECO2 relative to Cd50_ACO2. Activities of superoxide dismutase (SOD) and peroxidase (POD) enhanced by 8.42% and 185.01%, respectively, while glutathione (GSH) and ascorbic acid (AsA) contents increased by 16.44% and 52.48%, and abundances of rhizosphere microbes changed significantly under coupled stresses (Cd50_ECO2) relative to Cd-stress alone (Cd50_ACO2). Also, the upregulation of glutathione, glutathione transferase genes, and heavy metal ATPase expression promoted the detoxification effect of rapeseed on Cd. Changes in the expression of transcription factors like MAPK, WRKY, BAK1 and PR1, as well as changes in metabolic pathways like ß-alanine, may be involved in the regulatory mechanism of stress response. These findings provide new insights for studying the regulatory mechanism of rapeseed under ECO2 on soil Cd stress, and also provide a basis for further research on Cd tolerant rapeseed varieties in the future climate context.

7.
Exp Cell Res ; 442(2): 114252, 2024 Sep 10.
Article de Anglais | MEDLINE | ID: mdl-39260674

RÉSUMÉ

The present study aimed to explore the expression and regulatory role of FAM83D in the different developmental stages of esophageal squamous cell carcinoma (ESCC) to determine the effect of FAM83D on the proliferation, migration, and invasion of ESCC cells and to elucidate its underlying molecular mechanism. Immunohistochemistry (IHC) analysis revealed that the expression of FAM83D was obviously elevated in ESCC tissues compared to adjacent normal tissues. Furthermore, the FAM83D levels was positively correlated with tumor size, TNM stage, T stage, and N stage, while it was negatively correlated with FBXW7 expression, Karnofsky Performance Status (KPS) score, and survival rate. Subsequently, ESCC cell lines with low FAM83D expression were constructed using RNA interference technology to investigate the impact of FAM83D on the biological behavior of ESCC cells. Silencing of FAM83D inhibited the proliferation and migration of ESCC cells but promoted apoptosis. Furthermore, a reduction in FAM83D expression may also induce cell cycle arrest at the G0/G1 phase and regulate the expression of proteins related to epithelial-mesenchymal transition (EMT), the cell cycle, and apoptosis. Further research indicated that silencing FAM83D led to the upregulation of FBXW7 expression. These results suggested that FAM83D may exert its effects on ESCC by downregulating FBXW7. Additionally, using a 4NQO solution in the drinking water to establish an ESCC mouse model, IHC analysis revealed that FAM83D expression levels were positively correlated with the pathological grade of esophageal lesions in the mice and negatively correlated with the expression levels of FBXW7 and E-cadherin. The above results demonstrated that FAM83D may facilitate the progression of ESCC by negatively regulating FBXW7 expression and that FAM83D could represent a promising therapeutic target for ESCC.

8.
Int J Surg ; 2024 Sep 05.
Article de Anglais | MEDLINE | ID: mdl-39236098

RÉSUMÉ

BACKGROUND: Human umbilical cord mesenchymal stem cells derived extracellular vesicles (HUMSC-EVs) have drawn much interest in kidney transplantation, mainly because of their renoprotection by alleviating cell injury and stimulating tissue repair. Cellular senescence has been proven to play a dual regulatory role in kidney ischemia-reperfusion injury (IRI), and the regulation of HUMSC-EVs on tubular epithelial cell senescence may be a potential therapeutic target. MATERIALS AND METHODS: In vitro, the hypoxia-reoxygenation of human kidney-2 cells was used to simulate kidney IRI, and the regulation of HUMSC-EVs on human kidney-2 cells was detected. Transcriptome sequencing of human kidney-2 cells was used to explore the potential regulatory mechanism. In vivo, adult male mice were divided into five groups: control group, IRI group, HUMSC-EVs treatment group, senolytics treatment group (dasatinib + quercetin), and combined treatments group (HUMSC-EVs and senolytics). Kidney function, senescent features of tubular epithelial cells, acute kidney injury, and chronic interstitial fibrosis in mice were detected to explore the renoprotection effects of HUMSC-EVs. RESULTS: Kidney IRI significantly up-regulated expressions of LaminB1, p53, p21, p16, senescence-associated beta-galactosidase, and apoptosis of tubular epithelial cells. In the mouse kidney IRI model, kidney subcapsular injection of HUMSC-EVs significantly improved kidney function, reducing the senescent features of tubular epithelial cells and alleviating acute kidney injury and chronic interstitial fibrosis. HUMSC-EVs mainly achieved renoprotection by regulating Bax/Bcl-2-dependent apoptosis during acute kidney injury and mostly reduced tubular atrophy and kidney interstitial fibrosis by regulating Ras-pERK-Ets1-p53 pathway-dependent cell senescence. Oral administration of senolytics also alleviated kidney injury induced by IRI, while the combined treatments of HUMSC-EVs and senolytics had better renoprotection effects. CONCLUSIONS: The combination of HUMSC-EVs and senolytics alleviated acute kidney injury and chronic interstitial fibrosis by dynamic regulation of cell senescence and apoptosis, which provides a therapeutic potential strategy for organ preservation and tissue repair in kidney transplantation.

9.
Clin Genitourin Cancer ; 22(6): 102203, 2024 Aug 13.
Article de Anglais | MEDLINE | ID: mdl-39241310

RÉSUMÉ

PURPOSE: To investigate the safety and effectiveness of radiotherapy for advanced upper tract urothelial carcinoma (UTUC) patients intolerant to chemotherapy. METHODS: Data for 21 patients with advanced UTUC intolerant to chemotherapy were retrospectively collected. All patients were treated with conventionally fractionated radiotherapy (50-70 Gy/20-33 f) or partial-SABR boost to the lesions (50-60 Gy/20-25 f with tumor center boosted with 6-8 Gy/f, 3-5 f) for bulky tumors. RESULTS: The median age was 75 years (range, 58-87 years). Primary tumor resection was performed for all patients and none underwent metastatic resection. Seventeen (81%) patients had oligometastasis (1-5 metastases) at diagnosis. Eighteen (85.7%) received irradiation to all tumor lesions. Lymph node metastasis was predominant in the whole group (17/21). Other lesions were distributed as local recurrence (7/21), bone metastases (2/21) and abdominal wall/muscle (2/21). The median follow-up time was 38.5 months (interquartile range, 15.2-48.7 months). Rate of local control (LC), progression-free survival (PFS) and overall survival (OS) of the whole group at 1 year were 90%, 46.6%, and 80.4%, respectively. At 3 years, LC, PFS and OS were 65.6%, 26.6%, and 40.9%, respectively. Fourteen patients developed acute mild gastrointestinal toxicity, generally of grade 1-2; 8 patients developed acute grade 1-2 hematological toxicity, consisting mainly of anemia and leukopenia. No grade 3 or higher acute or late toxicities were observed. CONCLUSION: For patients with advanced UTUC who are not able to tolerate chemotherapy, radiotherapy is a safe treatment and can achieve good local tumor control.

10.
Mycoscience ; 65(3): 151-155, 2024.
Article de Anglais | MEDLINE | ID: mdl-39233760

RÉSUMÉ

The present study introduces a novel fungus, Cystoderma yongpingense, which was identified in the southwestern region of China. The new species is characterized by a pileus that ranges in color from light orange-red to orange-red; the pileus has a wrinkled surface and is accompanied by a persistent annulus that is membranous and floccose-scaly. Above the annulus, the color transitions from white to yellowish brown. This proposal is substantiated through analyses encompassing both morphological characteristics and phylogenetic relationships. The phylogenetic position of the newly discovered species has been further corroborated through comprehensive maximum likelihood and Bayesian sequence analyses of the ITS + nrLSU DNA regions. Additionally, the technical description of C. yongpingense is enhanced by detailed illustrations and comparative studies with species that are closely related.

11.
Polymers (Basel) ; 16(17)2024 Aug 27.
Article de Anglais | MEDLINE | ID: mdl-39274057

RÉSUMÉ

Temperature and pressure sensors currently encounter challenges such as slow response times, large sizes, and insufficient sensitivity. To address these issues, we developed tetraphenylethylene (TPE)-doped polyvinylidene fluoride (PVDF) nanofiber membranes using electrospinning, with process parameters optimized through a convolutional neural network (CNN). We systematically analyzed the effects of PVDF concentration, spinning voltage, tip-to-collector distance, and flow rate on fiber morphology and diameter. The CNN model achieved high predictive accuracy, resulting in uniform and smooth nanofibers under optimal conditions. Incorporating TPE enhanced the hydrophobicity and mechanical properties of the nanofibers. Additionally, the fluorescent properties of the TPE-doped nanofibers remained stable under UV exposure and exhibited significant linear responses to temperature and pressure variations. The nanofibers demonstrated a temperature sensitivity of -0.976 gray value/°C and pressure sensitivity with an increase in fluorescence intensity from 537 a.u. to 649 a.u. under 600 g pressure. These findings highlight the potential of TPE-doped PVDF nanofiber membranes for advanced temperature and pressure sensing applications.

12.
Heliyon ; 10(17): e36684, 2024 Sep 15.
Article de Anglais | MEDLINE | ID: mdl-39263146

RÉSUMÉ

Increasing evidence indicates that the remodeling of immune microenvironment heterogeneity influences pancreatic cancer development, as well as sensitivity to chemotherapy and immunotherapy. However, a gap remains in the exploration of the immunosenescence microenvironment in pancreatic cancer. In this study, we identified two immunosenescence-associated isoforms (IMSP1 and IMSP2), with consequential differences in prognosis and immune cell infiltration. We constructed the MLIRS score, a hazard score system with robust prognostic performance (area under the curve, AUC = 0.91), based on multiple machine learning algorithms (101 cross-validation methods). Patients in the high MLIRS score group had worse prognosis (P < 0.0001) and lower abundance of immune cell infiltration. Conversely, the low MLIRS score group showed better sensitivity to chemotherapy and immunotherapy. Additionally, our MLIRS system outperformed 68 other published signatures. We identified the immunosenescence microenvironmental windsock GLUT1 with certain co-expression properties with immunosenescence markers. We further demonstrated its positive modulation ability of proliferation, migration, and gemcitabine resistance in pancreatic cancer cells. To conclude, our study focused on training of composite machine learning algorithms in multiple datasets to develop a robust machine learning modeling system based on immunosenescence and to identify an immunosenescence-related microenvironment windsock, providing direction and guidance for clinical prediction and application.

13.
Adv Sci (Weinh) ; : e2407069, 2024 Sep 03.
Article de Anglais | MEDLINE | ID: mdl-39225567

RÉSUMÉ

Lipid metabolism reprogramming stands as a fundamental hallmark of cancer cells. Unraveling the core regulators of lipid biosynthesis holds the potential to find promising therapeutic targets in pancreatic ductal adenocarcinoma (PDAC). Here, it is demonstrated that platelet-derived growth factor C (PDGFC) orchestrated lipid metabolism, thereby facilitated the malignant progression of PDAC. Expression of PDGFC is upregulated in PDAC cohorts and is corelated with a poor prognosis. Aberrantly high expression of PDGFC promoted proliferation and metastasis of PDAC both in vitro and in vivo. Mechanistically, PDGFC accelerated the malignant progression of PDAC by upregulating fatty acid accumulation through sterol regulatory element-binding protein 1 (SREBP1), a key transcription factor in lipid metabolism. Remarkably, Betulin, an inhibitor of SREBP1, demonstrated the capability to inhibit proliferation and metastasis of PDAC cell lines, along with attenuating the process of liver metastasis in vivo. Overall, the study underscores the pivotal role of PDGFC-mediated lipid metabolism in PDAC progression, suggesting PDGFC as a potential biomarker for PDAC metastasis. Targeting PDGFC-induced lipid metabolism emerges as a promising therapeutic strategy for metastatic PDAC, with the potential to improve clinical outcomes.

14.
Int J Biol Macromol ; 278(Pt 1): 134686, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39142486

RÉSUMÉ

This study presents a thrombin-loaded cationized chitosan (TCCS) sponge with highly effective hemostatic and antibacterial activity. The TCCS sponge, prepared using a multistep method, features a porous structure, favorable mechanical properties, excellent water absorption ability, and shape recovery triggered by water or blood. The TCCS sponge exhibited strong antibacterial activity against Methicillin-resistant Staphylococcus aureus and Escherichia coli. Additionally, it demonstrated enhanced procoagulant and hemostatic efficacy in rat tail amputation and rat liver perforation wound models compared to commercial hemostats. Furthermore, the sponge exhibited favorable biocompatibility and biosafety. These findings suggest that the TCCS sponge has substantial potential for practical applications in managing severe hemorrhages and bacterial infections.


Sujet(s)
Antibactériens , Chitosane , Hémostase , Hémostatiques , Staphylococcus aureus résistant à la méticilline , Thrombine , Chitosane/composition chimique , Chitosane/pharmacologie , Animaux , Antibactériens/pharmacologie , Antibactériens/composition chimique , Rats , Hémostatiques/composition chimique , Hémostatiques/pharmacologie , Thrombine/pharmacologie , Hémostase/effets des médicaments et des substances chimiques , Staphylococcus aureus résistant à la méticilline/effets des médicaments et des substances chimiques , Cations/composition chimique , Escherichia coli/effets des médicaments et des substances chimiques , Mâle , Porosité
15.
Se Pu ; 42(9): 866-874, 2024 Sep.
Article de Chinois | MEDLINE | ID: mdl-39198945

RÉSUMÉ

Concerns over the emergence of steroid hormones as pollutants in water have grown. Steroid hormone compounds present challenges in the simultaneous detection of total residual hormones owing to their analogous structures and diverse types. In this study, we established a rapid and high-throughput continuous online method based on solid phase extraction (SPE) coupled with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the simultaneous determination of 61 hormone components, including 48 glucocorticoids, 1 mineralocorticoid, 4 androgens, and 8 progesterones, in water. Various SPE columns were investigated to assess their extraction efficiency for enriching and purifying target compounds in a large sample volume (1 L). An HC-C18 SPE column was selected because of its superior performance. Acetonitrile was used as a washing solution during SPE to ensure that the majority of the tested substances achieved recoveries exceeding 70% and effectively avoid interferences from water-soluble components. Various C8 and C18 columns were tested, and the optimal HPLC conditions for hormone retention were established. We systematically evaluated different UPLC columns and mobile phases, including methanol-water and acetonitrile-water systems with 0.1% formic acid added to the aqueous phase. The optimized UPLC conditions were as follows: BEH C18 column (100 mm×2.1 mm, 1.7 µm); column temperature, 40 ℃; flow rate, 0.3 mL/min; injection volume, 5 µL; mobile phase A: 0.1% formic acid aqueous phase; mobile phase B: acetonitrile. Gradient elution was performed as follows: 0-0.5 min, 30%B; 0.5-15.0 min, 30%B-75%B; 15.0-18.0 min, 75%B-98%B; 18.0-19.0 min, 98%B; 19.0-19.1 min, 98%B-30%B; 19.1-20.0 min, 30%B. Both positive- and negative-ion modes were explored in the UPLC-MS/MS experiment to obtain the full scan of the parent ions, and positive mode was finally selected for electrospray ionization (ESI). Two product ions exhibiting strong signals and minimal interference were selected for quantitative and qualitative ion analyses, using an external standard method for quantification. MS/MS was performed in positive-ion (ESI+) mode with multiple reaction monitoring (MRM) scanning. The MS/MS parameters were as follows: atomizing gas pressure, 379 kPa; curtain air pressure, 241 kPa; spray voltage, 5500 V; desolvation temperature, 550 ℃; collision exit voltage (CXP), 13 V; intake voltage (EP), 10 V; and residence time of each ion pair, 0.5 ms. Other instrument settings, such as the collision energy and declustering voltage, were also optimized. The 61 hormones exhibited excellent linear relationships within their corresponding concentration ranges, with correlation coefficients greater than 0.99. The method detection limits (MDLs) were in the range of 0.05-1.50 ng/L. The average recoveries of the 61 hormones across three spiked levels ranged from 62.3% to 125.2%, with relative standard deviations (RSDs, n=6) of 1.1%-10.5%. Using this method, we successfully detected 10 hormone components (cortisone, fluticasone propionate, ciclesonide, betamethasone dipropionate, clobetasone butyrate, diflucortolone valerate, halobetasol propionate, isoflupredone, difluprednate, and hydroxyprogesterone caproate) in various surface water and groundwater samples collected from the Taihu Basin region. The SPE-UPLC-MS/MS method presented in this paper is simple, highly sensitivity, and exceptionally accurate. Thus, it exhibits promising potential for tracing targeted hormone residues in water and will be of great value in monitoring and ensuring water safety. Finally, a regional analysis was conducted on the hormone levels in water, and suggestions were made for the targeted treatment of hormone residues in future sewage treatment processes.


Sujet(s)
Extraction en phase solide , Spectrométrie de masse en tandem , Polluants chimiques de l'eau , Spectrométrie de masse en tandem/méthodes , Chromatographie en phase liquide à haute performance/méthodes , Extraction en phase solide/méthodes , Polluants chimiques de l'eau/analyse , Hormones/analyse
16.
Natl Sci Rev ; 11(9): nwae019, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39144740

RÉSUMÉ

The current-carrying friction characteristics are crucial for the performance of a sliding electrical contact, which plays critical roles in numerous electrical machines and devices. However, these characteristics are influenced by multiple factors such as material surface quality, chemical reactions, and atmospheric environment, leading to a challenge for researchers to comprehensively consider these impacts. Structural superlubricity (SSL), a state of nearly zero friction and no wear between contact solid surfaces, provides an ideal experimental system for these studies. Here, with microscale graphite flakes on atomic-flattened Au surface under applied voltages, we observed two opposite friction phenomena, depending only on whether the edge of graphite flake was in contact with the Au substrate. When in contact the friction force would increase with an increasing voltage, otherwise, the friction force would decrease. Notably, when the voltage was turned off, the friction force quickly recovered to its original level, indicating the absence of wear. Through atmosphere control and molecular dynamics simulations, we revealed the mechanism to be the different roles played by the water molecules confined at the interface or adsorbed near the edges. Our experimental results demonstrate the remarkable tunable and robust frictional properties of SSL under an electrical field, providing an ideal system for the fundamental research of not only sliding electrical contacts, but also novel devices which demand tunable frictions.

17.
Molecules ; 29(15)2024 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-39125064

RÉSUMÉ

In the human body, carboxylesterases (CEs) play crucial roles in xenobiotic metabolism and lipid homeostasis. But abnormal expression of CEs is highly associated with some diseases, such as hyperlipidemia, diabetes, and liver cancer. Therefore, it is of great importance to develop an efficient tool for the accurate detection of CEs in living organisms. Herein, an innovative near-infrared (NIR) fluorescent probe, TTAP-AB, was designed for CE detection based on the aggregation-induced emission (AIE) mechanism. This probe exhibits rapid response (2 min), excellent sensitivity (limit of detection = 8.14 × 10-6 U/mL), and high selectivity to CEs. Additionally, owing to its good biocompatibility, the TTAP-AB probe enables the monitoring of dynamic changes in CE levels under drug-induced modulation in living cells and zebrafish. More importantly, the TTAP-AB probe was successfully employed to image liver tumors and assist in tumor resection through the real-time monitoring of CEs, indicating that TTAP-AB is promising to guide liver cancer surgery. Therefore, the TTAP-AB probe can not only enrich the strategies for CE detection in biological systems but also has great potential for some clinical imaging applications, including medical diagnosis, preclinical research, and imaging-guided surgery.


Sujet(s)
Carboxylic ester hydrolases , Colorants fluorescents , Danio zébré , Animaux , Colorants fluorescents/composition chimique , Souris , Humains , Carboxylic ester hydrolases/métabolisme , Imagerie optique/méthodes , Tumeurs du foie/métabolisme , Tumeurs du foie/imagerie diagnostique , Lignée cellulaire tumorale
18.
Langmuir ; 2024 Aug 16.
Article de Anglais | MEDLINE | ID: mdl-39148474

RÉSUMÉ

Dynamics of fluid transport in ultratight reservoirs such as organic-rich shales differ from those in high-permeable reservoirs due to the complex nature of fluid transport and fluid-solid interaction in nanopores. We present a multiphase multicomponent transport model for primary production and gas injection in shale, considering the dual-scale porosity and intricate fluid-solid interactions. The pore space in the shale matrix is divided into macropores and nanopores based on pore size distribution. We employ density functional theory (DFT) to account for fluid-solid interactions and to compute the inhomogeneous fluid density distribution and phase behavior within a dual-scale matrix. The calculated fluid thermodynamic properties and transmissibility values are then integrated into the multiphase multicomponent transport model grounded in Maxwell-Stefan theory to simulate primary oil production from and gas injection into organic-rich shales. Our findings highlight DFT's adeptness in detailing the complex fluid inhomogeneities within nanopores─a critical concept that a cubic equation of state does not capture. Fluids within pores are categorized into confined and bulk states, restricted by a threshold pore width of 30 nm. Different compositions of fluid mixtures are observed in macropores and nanopores: heavier hydrocarbon components preferentially accumulate in nanopores due to their strong fluid-solid interactions. We utilize the developed model to simulate hydrocarbon production from an organic-rich shale matrix as well as CO2 injection into the matrix. During primary hydrocarbon production, strong fluid-solid interactions in nanopores impede the mobility of heavy components in the near-wall region, leading to their confinement. Consequently, heavy components mostly remain within the nanopores in the shale matrix during primary hydrocarbon production. During the CO2 injection process, the injected CO2 alters fluid composition within macropores and nanopores, promoting fluid redistribution. Injected CO2 engages in competitive fluid-solid interactions against intermediate hydrocarbons, successfully displacing a considerable number of these hydrocarbons from the nanopores.

19.
Anal Chim Acta ; 1322: 343065, 2024 Sep 15.
Article de Anglais | MEDLINE | ID: mdl-39182991

RÉSUMÉ

Hydroxyl compounds are widely present in plants and play essential roles in plant growth and development. High-coverage detection of hydroxyl compounds is crucial for understanding the physiological processes of plants. Despite the prevalence of chemical derivatization-assisted liquid chromatography-high resolution mass spectrometry (CD-LC-HRMS) in high-coverage detection of compounds with diverse functional groups, the confident identification of these compounds after derivatization remains a significant challenge. Herein, a novel method was developed for the identification of pyridine (PY)-derivatized hydroxyl compounds by comparing the MS/MS similarity of derivatized and corresponding underivatized compounds. Fragmentation rules of standards were summarized, and theoretical calculations have demonstrated the MS/MS similarity of PY-derivatized hydroxyl compounds with their underivatized counterparts. The effectiveness of the developed method was demonstrated by identifying PY-derivatized authentic standards. A total of 90 hydroxyl compounds were putatively identified in maize using the proposed method. This method can significantly enhance ionization efficiency with minimal impact on the quality of the MS/MS spectra, enabling the effective utilization of mass spectra databases for the identification of hydroxyl compounds.


Sujet(s)
Pyridines , Spectrométrie de masse en tandem , Zea mays , Pyridines/composition chimique , Pyridines/analyse , Spectrométrie de masse en tandem/méthodes , Chromatographie en phase liquide/méthodes , Zea mays/composition chimique , Hydroxydes/composition chimique , Structure moléculaire ,
20.
J Food Sci ; 89(7): 4109-4122, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38957103

RÉSUMÉ

The elucidation of the interaction mechanism between phospholipids and milk proteins within emulsions is pivotal for comprehending the properties of infant formula fat globules. In this study, multispectral methods and molecular docking were employed to explore the relationship between phosphatidylcholine (PC) and whey protein isolate (WPI). Observations indicate that the binding constant, alongside thermodynamic parameters, diminishes as temperature ascends, hinting at a predominantly static quenching mechanism. Predominantly, van der Waals forces and hydrogen bonds constitute the core interactions between WPI and PC. This assertion is further substantiated by Fourier transform infrared spectroscopy, which verifies PC's influence on WPI's secondary structure. A detailed assessment of thermodynamic parameters coupled with molecular docking reveals that PC predominantly adheres to specific sites within α-lactalbumin, ß-lactoglobulin, and bovine serum albumin, propelled by a synergy of hydrophobic interactions, hydrogen bonding, and van der Waals forces, with binding energies noted at -5.59, -6.71, and -7.85 kcal/mol, respectively. An increment in PC concentration is observed to amplify the emulsification properties of WPI whilst concurrently diminishing the zeta potential. This study establishes a theoretical foundation for applying the PC-WPI interaction mechanism in food.


Sujet(s)
Liaison hydrogène , Interactions hydrophobes et hydrophiles , Simulation de docking moléculaire , Phosphatidylcholines , Thermodynamique , Protéines de lactosérum , Protéines de lactosérum/composition chimique , Phosphatidylcholines/composition chimique , Spectroscopie infrarouge à transformée de Fourier/méthodes , Lactoglobulines/composition chimique , Lactoglobulines/métabolisme , Émulsions/composition chimique , Lactalbumine/composition chimique , Lactalbumine/métabolisme , Sérumalbumine bovine/composition chimique , Préparation pour nourrissons/composition chimique
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