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1.
Precis Clin Med ; 7(2): pbae013, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38946731

RESUMO

Background: Myeloid differentiation factor 88 (MyD88) is the core adaptor for Toll-like receptors defending against microbial invasion and initiating a downstream immune response during microbiota-host interaction. However, the role of MyD88 in the pathogenesis of inflammatory bowel disease is controversial. This study aims to investigate the impact of MyD88 on intestinal inflammation and the underlying mechanism. Methods: MyD88 knockout (MyD88-/-) mice and the MyD88 inhibitor (TJ-M2010-5) were used to investigate the impact of MyD88 on acute dextran sodium sulfate (DSS)-induced colitis. Disease activity index, colon length, histological score, and inflammatory cytokines were examined to evaluate the severity of colitis. RNA transcriptome analysis and 16S rDNA sequencing were used to detect the potential mechanism. Results: In an acute DSS-colitis model, the severity of colitis was not alleviated in MyD88-/- mice and TJ-M2010-5-treated mice, despite significantly lower levels of NF-κB activation being exhibited compared to control mice. Meanwhile, 16S rDNA sequencing and RNA transcriptome analysis revealed a higher abundance of intestinal Proteobacteria and an up-regulation of the nucleotide oligomerization domain-like receptors (NLRs) signaling pathway in colitis mice following MyD88 suppression. Further blockade of the NLRs signaling pathway or elimination of gut microbiota with broad-spectrum antibiotics in DSS-induced colitis mice treated with TJ-M2010-5 ameliorated the disease severity, which was not improved solely by MyD88 inhibition. After treatment with broad-spectrum antibiotics, downregulation of the NLR signaling pathway was observed. Conclusion: Our study suggests that the suppression of MyD88 might be associated with unfavorable changes in the composition of gut microbiota, leading to NLR-mediated immune activation and intestinal inflammation.

2.
Life Sci ; 351: 122812, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38862063

RESUMO

AIMS: Despite islet transplantation has proved a great potential to become the standard therapy for type 1 diabetes mellitus (T1DM), this approach remains limited by ischemia, hypoxia, and poor revascularization in early post-transplant period as well as inflammation and life-long host immune rejection. Here, we investigate the potential and mechanism of human amniotic mesenchymal stem cells (hAMSCs)-islet organoid to improve the efficiency of islet engraftment in immunocompetent T1DM mice. MAIN METHODS: We generated the hAMSC-islet organoid structure through culturing the mixture of hAMSCs and islets on 3-dimensional-agarose microwells. Flow cytometry, whole-body fluorescent imaging, immunofluorescence, Calcein-AM/PI staining, ELISA, and qPCR were used to assess the potential and mechanism of shielding hAMSCs to improve the efficiency of islet transplantation. KEY FINDINGS: Transplant of hAMSC-islet organoids results in remarkably better glycemic control, an enhanced glucose tolerance, and a higher ß cell mass in vivo compared with control islets. Our results show that hAMSCs shielding provides an immune privileged microenvironment for islets and promotes graft revascularization in vivo. In addition, hAMSC-islet organoids show higher viability and reduced dysfunction after exposure to hypoxia and inflammatory cytokines in vitro. Finally, our results show that shielding with hAMSCs leads to the activation of PKA-CREB-IRS2-PI3K and PKA-PDX1 signaling pathways, up-regulation of SIL1 mRNA levels, and down-regulation of MT1 mRNA levels in ß cells, which ultimately promotes the synthesis, folding and secretion of insulin, respectively. SIGNIFICANCE: hAMSC-islet organoids can evidently increase the efficiency of islet engraftment and might develop into a promising alternative for the clinical treatment of T1DM.


Assuntos
Âmnio , Diabetes Mellitus Experimental , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Organoides , Animais , Células-Tronco Mesenquimais/citologia , Camundongos , Humanos , Transplante das Ilhotas Pancreáticas/métodos , Diabetes Mellitus Experimental/terapia , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/citologia , Âmnio/citologia , Transplante de Células-Tronco Mesenquimais/métodos , Diabetes Mellitus Tipo 1/terapia , Camundongos Endogâmicos C57BL , Masculino
3.
Brain Behav Immun ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944162

RESUMO

The gut microbiota and neurological development of neonatal mice are susceptible to environmental factors that may lead to altered behavior into adulthood. However, the role that changed gut microbiota and neurodevelopment early in life play in this needs to be clarified. In this study, by modeling early-life environmental changes by cross-fostering BALB/c mice, we revealed the effects of the environment during the critical period of postnatal development on adult social behavior and their relationship with the gut microbiota and the nervous system. The neural projections exist between the ascending colon and oxytocin neurons in the paraventricular nuclei (PVN), peripheral oxytocin levels and PVN neuron numbers decreased after cross-fostering, and sex-specific alteration in gut microbiota and its metabolites may be involved in social impairments and immune imbalances brought by cross-fostering via the gut-brain axis. Our findings also suggest that social cognitive impairment may result from a combination of PVN oxytocinergic neurons, gut microbiota, and metabolites.

4.
J Pediatr Urol ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38944627

RESUMO

INTRODUCTION: Many pediatric urology conditions affect putatively normal tissues or appear too commonly to be based solely on specific DNA mutations. Understanding epigenetic mechanisms in pediatric urology, therefore, has many implications that can impact cell and tissue responses to settings, such as environmental and hormonal influences on urethral development, uropathogenic infections, obstructive stimuli, all of which originate externally or extracellularly. Indeed, the cell's response to external stimuli is often mediated epigenetically. In this commentary, we highlight work on the critical role that epigenetic machinery, such as DNA methyltransferases (DNMTs), Enhancer of Zeste Polycomb Repressive Complex 2 Subunit (EZH2), and others play in regulating gene expression and cellular functions in three urological contexts. DESIGN: Animal and cellular constructs were used to model clinical pediatric uropathology. The hypertrophy, trabeculation, and fibrosis of the chronically obstructed bladder was explored using smooth muscle cell models employing disorganised vs. normal extracellular matrix (ECM), as well as a new animal model of chronic obstructive bladder disease (COBD) which retains its pathologic features even after bladder de-obstruction. Cell models from human and murine hypospadias or genital tubercles (GT) were used to illustrate developmental responses and epigenetic dependency of key developmental genes. Finally, using bladder urothelial and organoid culture systems, we examined activity of epigenetic machinery in response to non uropathogenic vs. uropathogenic E.coli (UPEC). DNMT and EZH2 expression and function were interrogated in these model systems. RESULTS: Disordered ECM exerted a principal mitogenic and epigenetic role for on bladder smooth muscle both in vitro and in CODB in vivo. Key genes, e.g., BDNF and KCNB2 were under epigenetic regulation in actively evolving obstruction and COBD, though each condition showed distinct epigenetic responses. In models of hypospadias, estrogen strongly dysregulated WNT and Hox expression, which was normalized by epigenetic inhibition. Finally, DNA methylation machinery in the urothelium showed specific activation when challenged by uropathogenic E.coli. Similarly, UPEC induces hypermethylation and downregulation of the growth suppressor p16INK4A. Moreover, host cells exposed to UPEC produced secreted factors inducing epigenetic responses transmissible from one affected cell to another without ongoing bacterial presence. DISCUSSION: Microenvironmental influences altered epigenetic activity in the three described urologic contexts. Considering that many obstructed bladders continue to display abnormal architecture and dysfunction despite relief of obstruction similar to after resection of posterior valves or BPH, the epigenetic mechanisms described highlight novel approaches for understanding the underlying smooth muscle myopathy of this crucial clinical problem. Similarly, there is evidence for an epigenetic basis of xenoestrogen on development of hypospadias, and UTI-induced pan-urothelial alteration of epigenetic marks and propensity for subsequent (recurrent) UTI. The impact of mechanical, hormonal, infectious triggers on genitourinary epigenetic machinery activity invite novel avenues for targeting epigenetic modifications associated with these non-cancer diseases in urology. This includes the use of deactivated CRISPR-based technologies for precise epigenome targeting and editing. Overall, we underscore the importance of understanding epigenetic regulation in pediatric urology for the development of innovative therapeutic and management strategies.

5.
Curr Res Food Sci ; 8: 100782, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38939610

RESUMO

Discriminant analysis of similar food samples is an important aspect of achieving food quality control. The effective combination of Raman spectroscopy and machine learning algorithms has become an extremely attractive approach to develop intelligent discrimination techniques. Feature spectral analysis can help researchers gain a deeper understanding of the data patterns in food quality discrimination. Herein, this work takes the discrimination of three brands of dairy products as an example to investigate the Raman spectral feature based on the support vector machines (SVM), extreme learning machines (ELM) and convolutional neural network (CNN) algorithms. The results show that there are certain differences in the optimal spectral feature interval corresponding to different machine learning algorithms. Selecting the appropriate spectral feature interval can maintain high recognition accuracy and improve the computational efficiency of the algorithm. For example, the SVM algorithm has a recognition accuracy of 100% in the 890-980 cm-1, 1410-1500 cm-1 fusion spectral range, which takes about 200 s. The ELM algorithm also has a recognition accuracy of 100% in the 890-980 cm-1, 1410-1500 cm-1 fusion spectral range, which takes less than 0.3 s. The CNN algorithm has a recognition accuracy of 100% in the 890-980 cm-1, 1050-1180 cm-1, 1410-1500 cm-1 fusion spectral range, which takes about 80 s. In addition, by analyzing the distribution of spectral feature intervals based on Euclidean distance, the distribution of experimental samples based on feature spectra is visually displayed. Through the spectral feature analysis process of similar samples, a set of analysis strategies is provided to deeply reveal the data foundation of classification algorithms, which can provide reference for the analysis of relevant discriminative research patterns.

6.
Plant Cell Environ ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38863246

RESUMO

The shortage of decades-long continuous measurements of ecosystem processes limits our understanding of how changing climate impacts forest ecosystems. We used continuous eddy-covariance and hydrometeorological data over 2002-2022 from a young Douglas-fir stand on Vancouver Island, Canada to assess the long-term trend and interannual variability in evapotranspiration (ET) and transpiration (T). Collectively, annual T displayed a decreasing trend over the 21 years with a rate of 1% yr-1, which is attributed to the stomatal downregulation induced by rising atmospheric CO2 concentration. Similarly, annual ET also showed a decreasing trend since evaporation stayed relatively constant. Variability in detrended annual ET was mostly controlled by the average soil water storage during the growing season (May-October). Though the duration and intensity of the drought did not increase, the drought-induced decreases in T and ET showed an increasing trend. This pattern may reflect the changes in forest structure, related to the decline in the deciduous understory cover during the stand development. These results suggest that the water-saving effect of stomatal regulation and water-related factors mostly determined the trend and variability in ET, respectively. This may also imply an increase in the limitation of water availability on ET in young forests, associated with the structural and compositional changes related to forest growth.

7.
BMC Cancer ; 24(1): 714, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858644

RESUMO

BACKGROUND: Our study aims to explore the relationship, shared gene signature, and the underlying mechanisms that connect rheumatoid arthritis (RA) to colorectal cancer (CRC). METHODS: Mendelian randomization (MR) analysis was conducted to assess the causality between RA and CRC. Summary statistic data-based Mendelian randomization (SMR) leveraging eQTL data was employed to identify the CRC-related causal genes. Integrated analyses of single-cell RNA sequencing and bulk RNA sequencing were employed to comprehensively investigate the shared gene signature and potential mechanisms underlying the pathogenesis of both RA and CRC. Predictive analysis of the shared hub gene in CRC immunotherapy response was performed. Pan-cancer analyses were conducted to explore the potential role of MYO9A in 33 types of human tumors. RESULTS: MR analysis suggested that RA might be associated with a slight increased risk of CRC (Odds Ratio = 1.04, 95% Confidence Interval = 1.01-1.07, P = 0.005). SMR analysis combining transcriptome analyses identified MYO9A as a causal gene in CRC and a shared gene signature in both RA and CRC. MYO9A may contribute to tumor suppression, while downregulation of MYO9A may impact CRC tumorigenesis by disrupting epithelial polarity and architecture, resulting in a worse prognosis in CRC. Additionally, MYO9A shows promise as a powerful predictive biomarker for cancer prognosis and immunotherapy response in CRC. Pan-cancer analyses demonstrated MYO9A may have a protective role in the occurrence and progression of various human cancers. CONCLUSION: RA might be associated with a slight increased risk of CRC. MYO9A is a shared gene signature and a potential immune-related therapeutic target for both CRC and RA. Targeting the MYO9A-mediated loss of polarity and epithelial architecture could be a novel therapeutic approach for CRC.


Assuntos
Artrite Reumatoide , Neoplasias Colorretais , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Análise da Randomização Mendeliana , Miosinas/genética , Perfilação da Expressão Gênica , Transcriptoma , Locos de Características Quantitativas , Prognóstico , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , Multiômica
8.
Int J Surg ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833363

RESUMO

BACKGROUND: Tertiary lymphoid structures (TLSs) exert a crucial role in the tumor microenvironment (TME), impacting tumor development, immune escape, and drug resistance. Nonetheless, the heterogeneity of TLSs in colorectal cancer (CRC) and their impact on prognosis and treatment response remain unclear. METHODS: We collected genome, transcriptome, clinicopathological information, and digital pathology images from multiple sources. An unsupervised clustering algorithm was implemented to determine diverse TLS patterns in CRC based on the expression levels of 39 TLS signature genes (TSGs). Comprehensive explorations of heterogeneity encompassing mutation landscape, TME, biological characteristics, response to immunotherapy, and drug resistance were conducted using multi-omics data. TLSscore was then developed to quantitatively assess TLS patterns of individuals for further clinical applicability. RESULTS: Three distinct TLS patterns were identified in CRC. Cluster 1 exhibited upregulation of proliferation-related pathways, high metabolic activity, and intermediate prognosis, while Cluster 2 displayed activation of stromal and carcinogenic pathways and a worse prognosis. Both Cluster 1 and Cluster 2 may potentially benefit from adjuvant chemotherapy. Cluster 3, characterized by the activation of immune regulation and activation pathways, demonstrated a favorable prognosis and enhanced responsiveness to immunotherapy. We subsequently employed a regularization algorithm to construct the TLSscore based on 9 core genes. Patients with lower TLSscore trended to prolonged prognosis and a more prominent presence of TLSs, which may benefit from immunotherapy. Conversely, those with higher TLSscore exhibited increased benefits from adjuvant chemotherapy. CONCLUSIONS: We identified distinct TLS patterns in CRC and characterized their heterogeneity through multi-omics analyses. The TLSscore held promise for guiding clinical decision-making and further advancing the field of personalized medicine in CRC.

9.
J Colloid Interface Sci ; 672: 329-337, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38850860

RESUMO

Mussel-inspired polydopamine (PDA) coating has been utilized extensively as versatile deposition strategies that can functionalize surfaces of virtually all substrates. However, the strong adhesion, stability and intermolecular interaction of PDA make it inefficient in certain applications. Herein, a green and efficient photocatalytic method was reported to remove adhesion and degrade PDA by using TiO2-H2O2 as photocatalyst. The photodegradation process of the PDA spheres was first undergone nanoscale disassembly to form soluble PDA oligomers or well-dispersed nanoparticles. Most of the disassembled PDA can be photodegraded and finally mineralized to CO2 and H2O. Various PDA coated templates and PDA hollow structures can be photodegraded by this strategy. Such process provides a practical strategy for constructing the patterned and gradient surfaces by the "top-down" method under the control of light scope and intensity. This sequential degradation strategy is beneficial to achieve the decomposition of highly crosslinked polymers.

10.
Insights Imaging ; 15(1): 134, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837049

RESUMO

OBJECTIVE: To investigate whether intrauterine chilled saline can reduce endometrial impairment during US-guided percutaneous microwave ablation (PMWA) of adenomyosis. METHODS: An open-label, randomized trial was conducted with sixty symptomatic adenomyosis patients who were randomly assigned (1:1) to receive PMWA treatment assisted by intrauterine saline instillation (study group) or traditional PMWA treatment alone (control group). The primary endpoint was endometrial perfusion impairment grade on post-ablation contrast-enhanced MRI. The secondary endpoints were endometrial dehydration grade, ablation rate, and intra-ablation discomfort. RESULTS: The baseline characteristics of the two groups were similar. The incidence rates of endometrial perfusion impairment on MRI in the study and control groups were 6.7% (2/30) and 46.7% (14/30), respectively (p < 0.001). There were 28 (93.3%), 2 (6.7%), 0, and 0 patients in the study group and 16 (53.3%), 7 (23.3%), 5 (16.7%), and 2 (6.7%) in the control group (p < 0.001) who had grade 0, 1, 2, and 3 perfusion impairment, respectively. Additionally, there were 27 (90%), 3 (10%), and 0 patients in the study group and 19 (63.3%), 10 (33.3%), and 1 (3.3%) in the control group who had grade 0, 1, and 2 endometrial dehydration (p = 0.01). The ablation rates achieved in the study and control groups were 93.3 ± 17% (range: 69.2-139.6%) and 99.7 ± 15.7% (range: 71.5-129.8%), and they were not significantly different (p = 0.14). No significant difference was found in the intra-ablation discomfort. CONCLUSION: Intrauterine chilled saline can effectively reduce endometrial impairment after PMWA treatment for adenomyosis. CRITICAL RELEVANCE STATEMENT: This trial demonstrated that the instillation of intrauterine chilled saline reduced endometrial impairment on MRI during PMWA of adenomyosis. This approach allows more precise and safe ablation in clinical practice. KEY POINTS: Endometrial impairment occurs in the PMWA treatment of adenomyosis. Intrauterine chilled saline can reduce endometrial impairment during PMWA for adenomyosis. An intrauterine catheter is a practical endometrial protecting method during thermal ablation. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2100053582. Registered 24 November 2021, www.chictr.org.cn/showproj.html?proj=141090 .

11.
PhytoKeys ; 243: 9-14, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38912087

RESUMO

Based on a critical examination of type specimens, images of living plants, and the literature has shown Rhododendronoligocarpum to be conspecific with R.leishanicum. Although slight variations in corolla colour exist amongst different populations of R.oligocarpum, it does not serve as a key distinguishing trait. Therefore, we reduced R.oligocarpum to a synonym of R.leishanicum, and recommend placing it in Subsection Maculifera.

12.
J Immunother Cancer ; 12(6)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38908856

RESUMO

BACKGROUND: Tertiary lymphoid structures (TLSs) serve as organized lymphoid aggregates that influence immune responses within the tumor microenvironment. This study aims to investigate the characteristics and clinical significance of TLSs and tumor-infiltrating lymphocytes (TILs) in clear cell renal cell carcinoma (ccRCC). METHODS: TLSs and TILs were analyzed comprehensively in 754 ccRCC patients from 6 academic centers and 532 patients from The Cancer Genome Atlas. Integrated analysis was performed based on single-cell RNA-sequencing datasets from 21 ccRCC patients to investigate TLS heterogeneity in ccRCC. Immunohistochemistry and multiplex immunofluorescence were applied. Cox regression and Kaplan-Meier analyses were used to reveal the prognostic significance. RESULTS: The study demonstrated the existence of TLSs and TILs heterogeneities in the ccRCC microenvironment. TLSs were identified in 16% of the tumor tissues in 113 patients. High density (>0.6/mm2) and maturation of TLSs predicted good overall survival (OS) (p<0.01) in ccRCC patients. However, high infiltration (>151) of scattered TILs was an independent risk factor of poor ccRCC prognosis (HR=14.818, p<0.001). The presence of TLSs was correlated with improved progression-free survival (p=0.002) and responsiveness to therapy (p<0.001). Interestingly, the combination of age and TLSs abundance had an impact on OS (p<0.001). Higher senescence scores were detected in individuals with immature TLSs (p=0.003). CONCLUSIONS: The study revealed the contradictory features of intratumoral TLSs and TILs in the ccRCC microenvironment and their impact on clinical prognosis, suggesting that abundant and mature intratumoral TLSs were associated with decreased risks of postoperative ccRCC relapse and death as well as favorable therapeutic response. Distinct spatial distributions of immune infiltration could reflect effective antitumor or protumor immunity in ccRCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Linfócitos do Interstício Tumoral , Estruturas Linfoides Terciárias , Microambiente Tumoral , Humanos , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/mortalidade , Estruturas Linfoides Terciárias/imunologia , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Neoplasias Renais/genética , Feminino , Masculino , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Pessoa de Meia-Idade , Prognóstico , Estudos de Coortes , Idoso
13.
J Agric Food Chem ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916549

RESUMO

Di-2-ethylhexyl phthalate (DEHP) is frequently used as a plasticizer to enhance the plasticity and durability of agricultural products, which pose adverse effects to human health and the environment. Aquaporin 1 (AQP1) is a main water transport channel protein and is involved in the maintenance of intestinal integrity. However, the impact of DEHP exposure on gut health and its potential mechanisms remain elusive. Here, we determined that DEHP exposure induced a compromised duodenum structure, which was concomitant with mitochondrial structural injury of epithelial cells. Importantly, DEHP exposure caused duodenum inflammatory epithelial cell damage and strong inflammatory response accompanied by activating the TLR4/MyD88/NF-κB signaling pathway. Mechanistically, DEHP exposure directly inhibits the expression of AQP1 and thus leads to an inflammatory response, ultimately disrupting duodenum integrity and barrier function. Collectively, our findings uncover the role of AQP1 in phthalate-induced intestinal disorders, and AQP1 could be a promising therapeutic approach for treating patients with intestinal disorders or inflammatory diseases.

14.
Org Biomol Chem ; 22(25): 5093-5096, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38847222

RESUMO

A new method for the synthesis of terminal olefins was developed through the reaction of the Corey-Chaykovsky reagent (dimethyl-sulfonium methylide) with readily available esters. After the domino process of nucleophilic addition, elimination and rearrangement in one pot, the terminal olefins were synthesized in high yields (up to 84%) under mild conditions. The synthetic method was well tolerated by many functional groups and a new route for the synthesis of various terminal olefin derivatives is provided. In the end, a possible reaction mechanism is proposed, which is supported by DFT calculations.

15.
Langmuir ; 40(25): 13265-13275, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38857070

RESUMO

Artificial photoelectrochemistry (PEC) has emerged as a promising and efficient technology for the sustainable conversion of solar energy into chemicals. In this study, we present a refined PEC process that enables the highly selective and stable production of piperonal and other valuable aldehydes through the oxidation of the corresponding alcohols. By employing Fe2O3 or TiO2 as the photoanode material and 2,2,6,6-tetramethylpiperidinooxy (TEMPO) as a redox mediator in an H2O/acetonitrile solution, we achieve 100% selectivity and a >95% Faradaic efficiency for piperonal production from piperonyl alcohol (PA) oxidation. Remarkably, we reveal the enhancing effect on the PA oxidation reactivity of appropriate-amount water in the solvent as it plays a crucial role in inhibiting the photoelectron-hole recombination efficiency and facilitating charge transfer. Mechanistic analysis suggests that TEMPO-mediated PA oxidation involves the formation of •O2- radicals by the reduction of oxygen on the cathode, resulting in water as the sole byproduct. Furthermore, our PEC oxidation system exhibits applications on the 100%-selective production of various conjugated aldehydes, including 4-anisaldehyde, cuminaldehyde, and the vitamin B6 derivative. By implementing a TiO2//Fe2O3 dual-photoanode system, we achieve an enhanced piperonal production rate of 31.2 µmol h-1 cm-2 at 1.0 V vs Ag/Ag+ and demonstrate its stability over a 102 h cyclic test, ensuring near-quantitative yield. This research illuminates the potential of the PEC strategy as a generally applicable method for the efficient production of high-value aldehydes.

16.
Inorg Chem ; 63(24): 11459-11469, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38842950

RESUMO

The performance of covalent-organic frameworks (COFs) for the photocatalytic extraction of uranium is greatly limited by the number of adsorption sites. Herein, inspired by electronegative redox reactions, we designed a nitrogen-oxygen rich pyrazine connected COF (TQY-COF) with multiple redox sites as a platform for extracting uranium via combining superaffinity and enhanced photoinduction. The preorganized bisnitrogen-bisoxygen donor configuration on TQY-COF is entirely matched with the typical geometric coordination of hexavalent uranyl ions, which demonstrates high affinity (tetra-coordination). In addition, the presence of the carbonyl group and pyrazine ring effectively stores and controls electron flow, which efficaciously facilitates the separation of e-/h+ and enhances photocatalytic performance. The experimental results show that TQY-COF removes up to 99.8% of uranyl ions from actual uranium mine wastewater under the light conditions without a sacrificial agent, and the separation coefficient reaches 1.73 × 106 mL g-1 in the presence of multiple metal ions, which realizes the precise separation in the complex environment. Importantly, DFT calculations further elucidate the coordination mechanism of uranium and demonstrate the necessity of the presence of N/O atoms in the photocatalytic adsorption of uranium.

17.
Ying Yong Sheng Tai Xue Bao ; 35(4): 997-1006, 2024 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-38884234

RESUMO

Water use efficiency (WUE) is a key indicator for predicting the impacts of climate change on ecosystem carbon and water cycles. Most studies have explored the changes in the response environment of WUE at a particular scale. Few studies have examined how WUE responds to environments at multiple scales, thus limiting our in-depth understanding of the cross-scale carbon and water cycles. In this study, we measured photosynthesis and transpiration in situ periodically and continuously from June to October 2022 in a community dominated by Artemisia ordosica in Mu Us Sandy Land, and analyzed the seasonal variations in WUE at leaf, canopy, and ecosystem scales. The results showed there were significant seasonal variations in leaf water use efficiency (WUEL), canopy water use efficiency (WUET), and ecosystem water use efficiency (WUEE). WUEL was large in June and small in both August and September, ranging from 0.73-2.98 µmol·mmol-1. Both WUET and WUEE were lowest in June and highest in July and August, ranging from 0.10-7.00 and 0.06-6.25 µmol·mmol-1. WUEL was significantly negatively correlated with stomatal conductance. WUET was significantly positively correlated with canopy conduc-tance and soil water content, and negatively correlated with vapor pressure deficit (VPD). There was a significant positive correlation between WUEE and soil water content (SWC10) in 10 cm soil depth. The structural equation model showed that SWC10 and air temperature affected net photosynthetic rate and transpiration rate by modifying stomatal conductance, and thus affecting WUEL. VPD and SWC10 affected WUET by altering transpiration. SWC10, air temperature, and VPD affected WUEE by regulating ecosystem gross primary productivity. The modelling of carbon and water cycles should thoroughly consider the path and intensity of the effect of environmental factors on WUE at multiple scales.


Assuntos
Artemisia , Ecossistema , Fotossíntese , Folhas de Planta , Transpiração Vegetal , Água , Artemisia/metabolismo , Artemisia/crescimento & desenvolvimento , Artemisia/fisiologia , Água/metabolismo , Água/análise , China , Folhas de Planta/metabolismo , Folhas de Planta/química , Clima Desértico , Mudança Climática , Estações do Ano
18.
Anal Chem ; 96(24): 10013-10020, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38836548

RESUMO

Traditional methods for the detection of pathogenic bacteria are time-consuming, less efficient, and sensitive, which affects infection control and bungles illness. Therefore, developing a method to remedy these problems is very important in the clinic to diagnose the pathogenic diseases and guide the rational use of antibiotics. Here, microfluidic electrochemical integrated sensor (MEIS) has been investigated, functionally for rapid, efficient separation and sensitive detection of pathogenic bacteria. Three-dimensional macroporous PDMS and Au nanotube-based electrode are successfully assembled into the modeling microchip, playing the functions of "3D chaotic flow separator" and "electrochemical detector," respectively. The 3D chaotic flow separator enhances the turbulence of the fluid, achieving an excellent bacteria capture efficiency. Meanwhile, the electrochemical detector provides a quantitative signal through enzyme-linked immunoelectrochemistry with improved sensitivity. The microfluidic electrochemical integrated sensor could successfully isolate Candida albicans (C. albicans) in the range of 30-3,000,000 CFU in the saliva matrix with over 95% capture efficiency and sensitively detect C. albicans in 1 h in oral saliva samples. The integrated device demonstrates great potential in the diagnosis of oral candidiasis and is also applicable in the detection of other pathogenic bacteria.


Assuntos
Candida albicans , Técnicas Eletroquímicas , Candida albicans/isolamento & purificação , Técnicas Eletroquímicas/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Saliva/microbiologia , Saliva/química , Eletrodos , Humanos , Ouro/química
20.
Fitoterapia ; 177: 106057, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38844141

RESUMO

The pericarps of Zanthoxylum schinifolium Sieb. et Zucc were called "green huajiao", which were used as traditional folk medicine and popular seasoning in China. In this study, twenty-seven alkylamides, including a rare alkylamide containing two amide groups (1), an alkylamide with a furan ring (5), six new alkylamide analogues (2-4, 6-8), together with nineteen known alkylamides (9-27) were isolated from green huajiao. Their structures were elucidated by extensive spectroscopic analysis, including 1D, 2D NMR, HRESIMS, and UV spectra. Furthermore, compounds 5, 18, 21, and 22 exhibited weak protective activity for corticosterone-induced PC12 cells damage.

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