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1.
Sci Total Environ ; 931: 172970, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38705293

RESUMO

Rivers in agricultural countries widely suffer from diffuse nitrate (NO3-) pollution. Although pollution sources and fates of riverine NO3- have been reported worldwide, the driving mechanisms of riverine NO3- pollution associated with mineral dissolution in piedmont zones remain unclear. This study combined hydrogeochemical compositions, stable isotopes (δ18O-NO3-, δ15N-NO3-, δ18O-H2O, and δ2H-H2O), and molecular bioinformation to determine the pollution sources, biogeochemical evolution, and natural attenuation of riverine NO3- in a typical piedmont zone (Qingshui River). High NO3- concentration (37.5 ± 9.44 mg/L) was mainly observed in the agricultural reaches of the river, with ~15.38 % of the samples exceeding the acceptable limit for drinking purpose (44 mg/L as NO3-) set by the World Health Organization. Ammonium inputs, microbial nitrification, and HNO3-induced calcite dissolution were the dominant driving factors that control riverine NO3- contamination in the piedmont zone. Approximately 99.4 % of riverine NO3- contents were derived from NH4+-containing pollutants, consisted of manure & domestic sewage (74.0 % ± 13.0 %), NH4+-synthetic fertilizer (16.1 % ± 8.99 %), and soil organic nitrogen (9.35 % ± 4.49 %). These NH4+-containing pollutants were converted to HNO3 (37.2 ± 9.38 mg/L) by nitrifying bacteria, and then the produced HNO3 preferentially participated in the carbonate (mainly calcite) dissolution, which accounted for 40.0 % ± 12.1 % of the total riverine Ca2+ + Mg2+, also resulting in the rapid release of NO3- into the river water. Thus, microbial nitrification could be a new and non-negligible contributor of riverine NO3- pollution, whereas the involvement of HNO3 in calcite dissolution acted as an accelerator of riverine NO3- pollution. However, denitrification had lesser contribution to natural attenuation for high NO3- pollution. The obtained results indicated that the mitigation of riverine NO3- pollution should focus on the management of ammonium discharges, and the HNO3-induced carbonate dissolution needs to be considered in comprehensively understanding riverine NO3- pollution in piedmont zones.


Assuntos
Compostos de Amônio , Carbonato de Cálcio , Monitoramento Ambiental , Nitratos , Nitrificação , Rios , Poluentes Químicos da Água , China , Rios/química , Nitratos/análise , Poluentes Químicos da Água/análise , Carbonato de Cálcio/química
2.
Food Chem ; 451: 139502, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38701732

RESUMO

In this study, the correlation between protein phosphorylation and deterioration in the quality of tilapia during storage in ice was examined by assessing changes in texture, water-holding capacity (WHC), and biochemical characteristics of myofibrillar protein throughout 7 days of storage. The hardness significantly decreased from 471.50 to 252.17 g, whereas cooking and drip losses significantly increased from 26.5% to 32.6% and 2.9% to 9.1%, respectively (P < 0.05). Myofibril fragmentation increased, while myofibrillar protein sulfhydryl content and Ca2+-ATPase activity decreased from 119.33 to 89.29 µmol/g prot and 0.85 to 0.46 µmolPi/mg prot/h, respectively (P < 0.05). Correlation analysis revealed that the myofibrillar protein phosphorylation level was positively correlated with hardness and Ca2+-ATPase activity but negatively correlated with WHC. Myofibrillar protein phosphorylation affects muscle contraction by influencing the dissociation of actomyosin, thereby regulating hardness and WHC. This study provides novel insights for the establishment of quality control strategies for tilapia storage based on protein phosphorylation.

3.
Heliyon ; 10(9): e30727, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38774095

RESUMO

Background: The FXYD domain-containing ion transport regulator 5 (FXYD5) gene is a cancer promoter. However, evidence for an association between FXYD5 and various types of cancer is still lacking. Using multi-omics bioinformatics, our study aimed to reveal the expression distribution, prognostic value, immune infiltration correlation, and molecular functions of FXYD5. Methods: Using pan-cancer multi-omics data (including The Cancer Genome Atlas, PrognoScan, Gene Expression Profiling Interactive Analysis, cBioPortal, Gene Expression Omnibus, TIMER and scTIME Portal), we assessed the differences in the expression and prognostic value of FXYD5 in malignant tumors. Furthermore, at the single-cell level, we analyze the expression distribution of FXYD5 across different cell types within the tumor microenvironment, and its relationship with the immune microenvironment. Finally, focusing on ovarian cancer, we conducted preliminary validation of the above findings using cell and molecular biology techniques. Results: Our results indicated that FXYD5 was up-regulated in various tumor types and was positively associated with tumor progression. We also revealed that FXYD5 was ubiquitously expressed in microenvironmental cells at the single-cell level, and its upregulation was associated with enhanced immune infiltration, cancer-associated fibroblast infiltration, and dysfunction of tumor-infiltrating cytotoxic T lymphocyte. Additionally, its expression was positively correlated with immune checkpoint genes, DNA mismatch repair genes, MSI (microsatellite instability) and TMB (tumor mutational burden) across various cancers. Its higher expression in cytotoxic T lymphocytes attenuated its ability to predict patient survival with PD-L1 (programmed death-ligand 1) blockade therapy, and FXYD5 was found to be a potential regulator of tumor immune escape and resistance to cancer immunotherapies. Based on GSEA (gene set enrichment analysis) and experimental verification, FXYD5 activated TGF-ß/SMAD signaling and drove EMT (epithelial-mesenchymal transition) to promote ovarian cancer progression. Conclusion: In summary, our study revealed that FXYD5-TGFß axis may coregulate the interaction between tumors, CAFs (carcinoma-associated fibroblasts) and immune cells to reshape the tumor immune microenvironment and promote tumorigenesis and tumor progression. Thus, FXYD5 could be used as an immune-related biomarker for diagnosing and predicting the prognosis of multiple cancer types. Therefore, our findings suggest that targeting FXYD5 in TME (tumor microenvironment) may be a promising therapeutic strategy.

4.
Front Microbiol ; 15: 1408926, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774502

RESUMO

Bidirectional trans-kingdom RNA silencing, a pivotal factor in plant-pathogen interactions, remains less explored in plant host-parasite dynamics. Here, using small RNA sequencing in melon root systems, we investigated microRNA (miRNA) expression variation in resistant and susceptible cultivars pre-and post-infection by the parasitic plant, broomrape. This approach revealed 979 known miRNAs and 110 novel miRNAs across 110 families. When comparing susceptible (F0) and resistant (R0) melon lines with broomrape infection (F25 and R25), 39 significantly differentially expressed miRNAs were observed in F25 vs. F0, 35 in R25 vs. R0, and 5 in R25 vs. F25. Notably, two miRNAs consistently exhibited differential expression across all comparisons, targeting genes linked to plant disease resistance. This suggests their pivotal role in melon's defense against broomrape. The target genes of these miRNAs were confirmed via degradome sequencing and validated by qRT-PCR, ensuring reliable sequencing outcomes. GO and KEGG analyses shed light on the molecular functions and pathways of these differential miRNAs. Furthermore, our study unveiled four trans-kingdom miRNAs, forming a foundation for exploring melon's resistance to broomrape.

5.
J Pineal Res ; 76(4): e12960, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38747028

RESUMO

Natural products, known for their environmental safety, are regarded as a significant basis for the modification and advancement of fungicides. Melatonin, as a low-cost natural indole, exhibits diverse biological functions, including antifungal activity. However, its potential as an antifungal agent has not been fully explored. In this study, a series of melatonin derivatives targeting the mitogen-activated protein kinase (Mps1) protein of fungal pathogens were synthesized based on properties of melatonin, among which the trifluoromethyl-substituted derivative Mt-23 exhibited antifungal activity against seven plant pathogenic fungi, and effectively reduced the severity of crop diseases, including rice blast, Fusarium head blight of wheat and gray mold of tomato. In particular, its EC50 (5.4 µM) against the rice blast fungus Magnaporthe oryzae is only one-fourth that of isoprothiolane (22 µM), a commercial fungicide. Comparative analyzes revealed that Mt-23 simultaneously targets the conserved protein kinase Mps1 and lipid protein Cap20. Surface plasmon resonance assays showed that Mt-23 directly binds to Mps1 and Cap20. In this study, we provide a strategy for developing antifungal agents by modifying melatonin, and the resultant melatonin derivative Mt-23 is a commercially valuable, eco-friendly and broad-spectrum antifungal agent to combat crop disease.


Assuntos
Antifúngicos , Melatonina , Melatonina/farmacologia , Melatonina/química , Melatonina/análogos & derivados , Antifúngicos/farmacologia , Antifúngicos/química , Doenças das Plantas/microbiologia , Proteínas Fúngicas/metabolismo , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Fungicidas Industriais/síntese química
6.
J Am Chem Soc ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747066

RESUMO

Ni-rich cathodes are some of the most promising candidates for advanced lithium-ion batteries, but their available capacities have been stagnant due to the intrinsic Li+ storage sites. Extending the voltage window down can induce the phase transition from O3 to 1T of LiNiO2-derived cathodes to accommodate excess Li+ and dramatically increase the capacity. By setting the discharge cutoff voltage of LiNi0.6Co0.2Mn0.2O2 to 1.4 V, we can reach an extremely high capacity of 393 mAh g-1 and an energy density of 1070 Wh kg-1 here. However, the phase transition causes fast capacity decay and related structural evolution is rarely understood, hindering the utilization of this feature. We find that the overlithiated phase transition is self-limiting, which will transform into solid-solution reaction with cycling and make the cathode degradation slow down. This is attributed to the migration of abundant transition metal ions into lithium layers induced by the overlithiation, allowing the intercalation of overstoichiometric Li+ into the crystal without the O3 framework change. Based on this, the wide-potential cycling stability is further improved via a facile charge-discharge protocol. This work provides deep insight into the overstoichiometric Li+ storage behaviors in conventional layered cathodes and opens a new avenue toward high-energy batteries.

7.
Chem Asian J ; : e202400443, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773630

RESUMO

Two polyhedral silver-thiolate clusters, [S@Ag16(Tab)10(MeCN)8](PF6)14 (Ag16) and [Ag12(Tab)6(DMF)12](PF6)12 (Ag12), were synthesized by using electroneutral Tab species as protective ligands (Tab = 4-(trimethylammonio)benzenethiolate, DMF = N,N-dimethylformamide, MeCN = acetonitrile). Ag16 has a decahedral shape composed of eight pentagon {Ag5} units and two square {Ag4} units. The structure of Ag12 is a cuboctahedron, a classical Archimedean structure composed of six triangular faces and eight square faces. The former configuration is discovered in silver-thiolate cluster for the first time, possibly benefited from the more flexible coordination between the Tab ligand and Ag+ facilitated by the electropositive -N(CH3)3 substituent group. Third-order nonlinear optical studies show that both clusters in DMF exhibit reverse saturate absorption response under the irradiation of 532 nm laser.

8.
World J Gastroenterol ; 30(18): 2440-2453, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38764767

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) with hepatic histological NAFLD activity score ≥ 4 and fibrosis stage F ≥ 2 is regarded as "at risk" non-alcoholic steatohepatitis (NASH). Based on an international consensus, NAFLD and NASH were renamed as metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH), respectively; hence, we introduced the term "high-risk MASH". Diagnostic values of seven non-invasive models, including FibroScan-aspartate transaminase (FAST), fibrosis-4 (FIB-4), aspartate transaminase to platelet ratio index (APRI), etc. for high-risk MASH have rarely been studied and compared in MASLD. AIM: To assess the clinical value of seven non-invasive models as alternatives to liver biopsy for diagnosing high-risk MASH. METHODS: A retrospective analysis was conducted on 309 patients diagnosed with NAFLD via liver biopsy at Beijing Ditan Hospital, between January 2012 and December 2020. After screening for MASLD and the exclusion criteria, 279 patients were included and categorized into high-risk and non-high-risk MASH groups. Utilizing threshold values of each model, sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV), were calculated. Receiver operating characteristic curves were constructed to evaluate their diagnostic efficacy based on the area under the curve (AUROC). RESULTS: MASLD diagnostic criteria were met by 99.4% patients with NAFLD. The MASLD population was analyzed in two cohorts: Overall population (279 patients) and the subgroup (117 patients) who underwent liver transient elastography (FibroScan). In the overall population, FIB-4 showed better diagnostic efficacy and higher PPV, with sensitivity, specificity, PPV, NPV, and AUROC of 26.9%, 95.2%, 73.5%, 72.2%, and 0.75. APRI, Forns index, and aspartate transaminase to alanine transaminase ratio (ARR) showed moderate diagnostic efficacy, whereas S index and gamma-glutamyl transpeptidase to platelet ratio (GPR) were relatively weaker. In the subgroup, FAST had the highest diagnostic efficacy, its sensitivity, specificity, PPV, NPV, and AUROC were 44.2%, 92.3%, 82.1%, 67.4%, and 0.82. The FIB-4 AUROC was 0.76. S index and GPR exhibited almost no diagnostic value for high-risk MASH. CONCLUSION: FAST and FIB-4 could replace liver biopsy as more effectively diagnostic methods for high-risk MASH compared to APRI, Forns index, ARR, S index, and GPR; FAST is superior to FIB-4.


Assuntos
Aspartato Aminotransferases , Técnicas de Imagem por Elasticidade , Fígado , Hepatopatia Gordurosa não Alcoólica , Valor Preditivo dos Testes , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Aspartato Aminotransferases/sangue , Técnicas de Imagem por Elasticidade/métodos , Fígado/patologia , Fígado/diagnóstico por imagem , Adulto , Biópsia , Curva ROC , Contagem de Plaquetas , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Idoso , Biomarcadores/sangue , Fatores de Risco , Medição de Risco/métodos
9.
J Colloid Interface Sci ; 669: 466-476, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38723535

RESUMO

Heterostructure engineering is considered a crucial strategy to modulate the intrinsic charge transfer behavior of materials, enhance catalytic activity, and optimize sulfur electrochemical processes. However, parsing the role of heterogeneous interface-structure-property relationships in heterostructures is still a key scientific issue to realize the efficient catalytic conversion of polysulfides. Based on this, molybdenum carbide (Mo2C) was successfully partial reduced to molybdenum metal (Mo) via a thermal reduction at high-temperature and the typical Mo-Mo2C-based Mott-Schottky heterostructures were simultaneously constructed, which realized the modulation of the electronic structure of Mo2C and optimized the conversion process of lithium polysulfides (LPS). Compared with single molybdenum carbide, the modulated molybdenum carbide acts as an electron donor with stronger Mo-S bonding strength as well as higher polysulfide adsorption energy, faster Li2S conversion kinetics, and greatly facilitates the adsorption → catalysis process of LPS. As a result, yolk-shell Mo-Mo2C heterostructure (C@Mo-Mo2C) exhibits excellent cycling performance as a sulfur host, with a discharge specific capacity of 488.41 mAh g-1 for C@Mo-Mo2C/S at 4 C and present an excellent high-rate cyclic performance accompanied by capacity decay rate of 0.08 % per cycle after 400 cycles at 2 C. Heterostructure-acting Mo2C electron distribution modulation engineering may contributes to the understanding of the structure-interface-property interaction law in heterostructures and further enables the efficient modulation of the chemical behavior of sulfur.

11.
J Cancer ; 15(10): 3199-3214, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706895

RESUMO

Backgrounds: Colorectal cancer (CRC) is a highly malignant gastrointestinal malignancy with a poor prognosis, which imposes a significant burden on patients and healthcare providers globally. Previous studies have established that genes related to glutamine metabolism play a crucial role in the development of CRC. However, no studies have yet explored the prognostic significance of these genes in CRC. Methods: CRC patient data were downloaded from The Cancer Genome Atlas (TCGA), while glutamine metabolism-related genes were obtained from the Molecular Signatures Database (MSigDB) database. Univariate COX regression analysis and LASSO Cox regression were utilized to identify 15 glutamine metabolism-related genes associated with CRC prognosis. The risk scores were calculated and stratified into high-risk and low-risk groups based on the median risk score. The model's efficacy was assessed using Kaplan-Meier survival analysis and receiver operating characteristic (ROC) curve analysis. Cox regression analysis was employed to determine the risk score as an independent prognostic factor for CRC. Differential immune cell infiltration between the high-risk and low-risk groups was assessed using the ssGSEA method. The clinical applicability of the model was validated by constructing nomograms based on age, gender, clinical staging, and risk scores. Immunohistochemistry (IHC) was used to detect the expression levels of core genes. Results: We identified 15 genes related to glutamine metabolism in CRC: NLGN1, RIMKLB, UCN, CALB1, SYT4, WNT3A, NRCAM, LRFN4, PHGDH, GRM1, CBLN1, NRG1, GLYATL1, CBLN2, and VWC2. Compared to the high-risk group, the low-risk group demonstrated longer overall survival (OS) for CRC. Clinical correlation analysis revealed a positive correlation between the risk score and the clinical stage and TNM stage of CRC. Immune correlation analysis indicated a predominance of Th2 cells in the low-risk group. The nomogram exhibited excellent discriminatory ability for OS in CRC. Immunohistochemistry revealed that the core gene CBLN1 was expressed at a lower level in CRC, while GLYATL1 was expressed at a higher level. Conclusions: In summary, we have successfully identified and comprehensively analyzed a gene signature associated with glutamine metabolism in CRC for the first time. This gene signature consistently and reliably predicts the prognosis of CRC patients, indicating its potential as a metabolic target for individuals with CRC.

12.
Cureus ; 16(4): e57503, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38707011

RESUMO

BACKGROUND: Life satisfaction is a comprehensive psychological index to measure a person's life quality. Previous studies have found that population sociological factors, physiological factors, psychological factors, and social factors all affect life satisfaction, but few studies have looked at the role of stable psychological factors, such as personality, in life satisfaction. Thus, this study combined previous research results and theories to study the current situation of college students' life satisfaction and its correlation with personality. OBJECTIVE: This study aims to comprehensively assess the life satisfaction levels among university students enrolled in a medical college in China, explore their correlation with various demographic factors and personality traits, identify potential areas for intervention, and provide recommendations for improving students' overall well-being and fostering the development of a positive and healthy personality. METHODS: A stratified cluster sampling method was used to select college students from a university. The questionnaire consists of general characteristics, a life satisfaction scale, and the Big Five Inventory. Descriptive statistical methods were conducted to describe the college students' life satisfaction status; an analysis of variance was performed to compare the score of life satisfaction among different demographic features; and the correlation between the score of life satisfaction and the Big Five Inventory was also analyzed. RESULTS: A total of 3116 subjects were included in this survey. The life satisfaction of females was higher than that of males in the dimensions of family, friends, school, and overall satisfaction (p<0.05). The life satisfaction of males in the self dimension was higher than that of females (p<0.05). The life satisfaction of different weight types had statistical significance in the life dimension (p<0.05). The life satisfaction of family, school, and overall well-being among smoking college students was lower than that of non-smoking college students (p<0.05). The life satisfaction of non-drinking college students in family, friends, life, school, and overall life satisfaction scores was higher than those of drinking college students (p<0.05). College students who get plenty of sleep a day (more than eight hours) scored higher life satisfaction scores in the self dimension than sleep-deprived college students (p<0.05). In addition to the family dimension, students taking long physical exercise breaks every day had higher life satisfaction scores in every dimension than students lacking physical exercise (p<0.05). The mean score of personality in the agreeableness and openness dimensions is the highest. Correlation analysis showed that the personality score in each dimension was positively correlated with the life satisfaction score in each dimension except for the neuroticism dimension of personality (p<0.05). CONCLUSION: The life satisfaction of college students is different for different lifestyles. The student management department should pay attention to the physical and mental health of college students with low life satisfaction and further find out the reasons for the difference in life satisfaction. Meanwhile, education should be strengthened for college students and encourage them to give up smoking and alcohol; strengthen physical training; and university education should strengthen the personality cultivation of college students.

13.
Asian Biomed (Res Rev News) ; 18(2): 61-68, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38708333

RESUMO

Background: The early diagnosis and treatment of cholangiocarcinoma may benefit from specific tumor markers to be used in clinical practice. Objectives: To investigate whether the pGCsiRNA-vascular endothelial growth factor (VEGF) can affect the onset and progression of cholangiocarcinoma and its possible mechanism using the targeted therapy of nude mouse model of cholangiocarcinoma with attenuated Salmonella carrying the plasmid pGCsiRNA-VEGF. Methods: The nude mouse model of cholangiocarcinoma was established by tail vein injection of QBC939 cells and given attenuated Salmonella carrying the plasmid pGCsiRNA-VEGF. One month later, the tumor volume of nude mice was observed, and the tumor growth curve was plotted. The harvested tumors were weighed and detected for tissue structural changes and cell death status by hematoxylin-eosin staining. The protein and mRNA expressions of VEGF, matrix metalloproteinase 2 (MMP2), and MMP9 were detected by Western blotting and PCR, respectively. Results: The tumor volume and weight of the pGCsiRNA-VEGF group were significantly smaller than those of the mock and the si-scramble groups (P < 0.05). The expressions of VEGF, MMP2, and MMP9 at the transcriptional and translational levels were inhibited by pGCsiRNA-VEGF. PGCsiRNA-VEGF promoted tissue apoptosis and destroyed the tissue structure. Conclusions: In vivo silencing of VEGF can affect cell survival and inhibit cell migration, invasion, and development, probably by enhancing apoptosis and inhibiting the expressions of MMP2 and MMP9.

14.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 40(4): 378-382, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38710522

RESUMO

One of the most prevalent malignancies in women is cervical cancer. Cervical cancer is mostly brought on by chronic high-risk human papillomavirus 16 (HPV16) and HPV18 infection. Currently, the widely used HPV vaccines are the bivalent Cervarix, the tetravalent Gardasil, and the 9-valent Gardasil-9.There are differences in T cell effector molecule changes, B cell antibody level, duration, age and the injection after vaccination of the three vaccines.


Assuntos
Linfócitos B , Vacinas contra Papillomavirus , Linfócitos T , Humanos , Vacinas contra Papillomavirus/imunologia , Vacinas contra Papillomavirus/administração & dosagem , Feminino , Linfócitos T/imunologia , Linfócitos B/imunologia , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Vacinação , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/virologia , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/imunologia , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/administração & dosagem , Papillomavirus Humano
15.
Angew Chem Int Ed Engl ; : e202403241, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710651

RESUMO

Exocytosis involving the fusion of intracellular vesicles with cell membrane, is thought to be modulated by the mechanical cues in the microenvironment. Single-cell electrochemistry can offer unique information about the quantification and kinetics of exocytotic events, however, the effects of mechanical force on vesicular release has been poorly explored. Herein, we developed a stretchable microelectrode with excellent electrochemical stability under mechanical deformation by microfabrication of functionalized poly(3,4-ethylenedioxythiophene) conductive ink, which achieved real-time quantitation of strain-induced vesicular exocytosis from a single cell for the first time. We found that mechanical strain could cause calcium influx via the activation of Piezo1 channel in chromaffin cell, initiating the vesicular exocytosis process. Interestingly, mechanical strain increases the amount of catecholamines release by accelerating the opening and prolonging the closing of fusion pore during exocytosis. This work is expected to provide a revealing insight on the regulatory effects of mechanical stimuli on vesicular exocytosis.

16.
Cardiovasc Diagn Ther ; 14(2): 251-263, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38716313

RESUMO

Background: The presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in myocardial autopsy tissues has been observed in certain individuals with coronavirus disease 2019 (COVID-19). However, the duration of cardiac involvement remains uncertain among recovered COVID-19 patients. Our study aims to evaluate the long-term persistence of SARS-CoV-2 within cardiac tissue. Methods: We prospectively and consecutively evaluated the patients undergoing mitral valve replacement (MVR) and left atrial (LA) volume reduction surgery from May 25 to June 10, 2023 at our center, who had been approximately 6 months of recovery after Omicron wave. Patients tested positive for SARS-CoV-2 upon admission were excluded. The surgical LA tissue was collected in RNA preservation solution and stored at -80 ℃ immediately. Then SARS-CoV-2, interleukin-6 (IL-6) and interleukin-1ß (IL-1ß) RNA expression in LA tissues were assessed through thrice-repeated reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analyses. Categorical variables were assessed using the Chi-square or Fisher's exact tests, and continuous variables was analyzed using the Mann-Whitney U test. Results: Nine of 41 patients were enrolled, all of whom tested negative for SARS-CoV-2 upon admission (two antigen and PCR tests). In four of nine patients, SARS-CoV-2 RNA was detected in their LA tissue, indicating viral colonization. Among the four positive cases, the IL-6 and IL-1ß relative expression levels in the LA tissue of one patient were increased approximately 55- and 110-fold, respectively, compared to those of SARS-CoV-2 (-) patients. Increased expression of IL-6 and IL-1ß were observed in the myocardium of this patient. Another patient demonstrated a remarkable 7-fold increase in both IL-6 and IL-1ß expression, surpassing that of SARS-CoV-2 (-) patients. Additionally, no other cardiac inflammation-related diseases or conditions were presented in these two patients. The IL-6 and IL-1ß expression levels of the remaining two patients were not significantly different from those of SARS-CoV-2 (-) patients. The relative expression levels of IL-6 and IL-1ß in cardiac tissues of all SARS-CoV-2 (-) patients were relatively low. Interestingly, despite abnormally elevated levels of IL-6 and IL-1ß within their cardiac tissue, two patients did not show a significant increase in serum IL-6 and IL-1ß levels when compared to other patients. Conclusions: Our research suggests that certain COVID-19-recovered patients have persistent colonization of SARS-CoV-2 in their cardiac tissue, accompanied by a local increase in inflammatory factors.

17.
ChemSusChem ; : e202400556, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728149

RESUMO

A photoactive covalent organic framework (COF) was built from metalloporphyrin and bipyridine monomers and single-atomic Pt sites were subsequently installed. Integrating photosensitizing metalloporphyrin and substrate-activating Pt(bpy) moieties in a single solid facilitates multielectron transfer and accelerates photocatalytic hydrogen evolution with a maximum production rate of 80.4 mmol h-1 gPt-1 and turnover frequency (TOF) of 15.7 h-1 observed. This work demonstrates that incorporation of single-atomic metal sites with photoactive COFs greatly enhances photocatalytic activity and provides an effective strategy for the design and construction of novel photocatalysts.

18.
Phytochemistry ; 223: 114121, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38697242

RESUMO

In this study, twenty-three ent-eudesmane sesquiterpenoids (1-23) including fifteen previously undescribed ones, named eutypelides A-O (1-15) were isolated from the marine-derived fungus Eutypella sp. F0219. Their planar structures and relative configurations were established by HR-ESIMS and extensive 1D and 2D NMR investigations. The absolute configurations of the previously undescribed compounds were determined by single-crystal X-ray diffraction analyses, modified Mosher's method, and ECD calculations. Structurally, eutypelide A (1) is a rare 1,10-seco-ent-eudesmane, whereas 2-15 are typically ent-eudesmanes with 6/6/-fused bicyclic carbon nucleus. The anti-neuroinflammatory activity of all isolated compounds (1-23) was accessed based on their ability to NO production in LPS-stimulated BV2 microglia cells. Compound 16 emerged as the most potent inhibitor. Further mechanistic investigation revealed that compound 16 modulated the inflammatory response by decreasing the protein levels of iNOS and increasing ARG 1 levels, thereby altering the iNOS/ARG 1 ratio and inhibiting macrophage polarization. qRT-PCR analysis showed that compound 16 reversed the LPS-induced upregulation of pro-inflammatory cytokines, including iNOS, TNF-α, IL-6, and IL-1ß, at both the transcriptional and translational levels. These effects were linked to the inhibition of the NF-κB pathway, a key regulator of inflammation. Our findings suggest that compound 16 may be a potential structure basis for developing neuroinflammation-related disease therapeutic agents.

19.
Abdom Radiol (NY) ; 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703190

RESUMO

PURPOSE: To develop a non-invasive auxiliary assessment method based on CT-derived extracellular volume (ECV) to predict the pathological grading (PG) of hepatocellular carcinoma (HCC). METHODS: The study retrospectively analyzed 238 patients who underwent HCC resection surgery between January 2013 and April 2023. Six machine learning algorithms were employed to construct predictive models for HCC PG: logistic regression, extreme gradient boosting, Light Gradient Boosting Machine (LightGBM), random forest, adaptive boosting, and Gaussian naive Bayes. Model performance was evaluated using receiver operating characteristic curve analysis, including area under the curve (AUC), sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and F1 score. Calibration plots were used for visual evaluation of model calibration. Clinical decision curve analysis was performed to assess potential clinical utility by calculating net benefit. RESULTS: 166 patients from Hospital A were allocated to the training set, while 72 patients from Hospital B (constituting 30.25% of the total sample) were assigned to the test set. The model achieved an AUC of 1.000 (95%CI: 1.000-1.000) in the training set and 0.927 (95%CI: 0.837-0.999) in the validation set, respectively. Ultimately, the model achieved an AUC of 0.909 (95%CI: 0.837-0.980) in the test set, with an accuracy of 0.778, sensitivity of 0.906, specificity of 0.789, negative predictive value of 0.556, and F1 score of 0.908. CONCLUSION: This study successfully developed and validated a non-invasive auxiliary assessment method based on CT-derived ECV to predict the HCC PG, providing important supplementary information for clinical decision-making.

20.
Environ Toxicol ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38708805

RESUMO

Small extracellular vesicles (sEVs) secreted by human umbilical cord have therapeutic effects on various degenerative diseases. However, the characteristics and potential functions of human umbilical cord mesenchymal stem cells (huMSCs)-derived sEVs, especially the role of premature ovarian failure (POF), are poorly understood. Here, we isolated and characterized huMSCs and their sEVs. huMSCs highly expressed CD73, CD90, and CD105. huMSC-sEVs showed typical exosomal features, highly expressing CD9, TSG101, and CD63. It was shown that huMSC-sEVs could be taken up by granulosa cells (GCs) and damaged ovarian tissue, which increased the levels of hormone secretion and reduced GCs apoptosis. We further confirmed that the levels of follicle-stimulating hormone in rat serum decreased dramatically, while the levels of estrogen (E2)and anti-mullerian hormone (AMH) increased significantly with the treatment of huMSC-sEVs. Meanwhile, huMSC-sEVs treatment greatly reduced cell apoptosis and autophagy, while increased the phosphorylation levels of p-PI3K and p-Akt. Therefore, treatment with huMSC-sEVs significantly inhibited GCs apoptosis, improved ovarian morphology, promoted follicular development, inhibited follicular over-atresia, and improved ovarian reserve capacity in POF rats. Our study verified that activation of PI3K/Akt signaling pathway and regulation of cellular autophagy, thus reducing GCs death, are the mechanisms by which huMSC-sEVs restore ovarian tissue function.

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