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1.
Integr Zool ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730493

RESUMO

Environmental DNA (eDNA) metabarcoding has emerged as a powerful, non-invasive tool for biodiversity assessments. However, the accuracy and limitations of these assessment techniques are highly dependent on the choice of primer pairs being used. Although several primer sets have been used in eDNA metabarcoding studies of amphibians, there are few comparisons of their reliability and efficiency. Here, we employed lab- and field-tested sets of publicly available and de novo-designed primers in amplifying 83 species of amphibian from all three orders (Anura, Caudata, and Gymnophiona) and 13 families present in China to evaluate the versatility and specificity of these primers sets in amphibian eDNA metabarcoding studies. Three pairs of primers were highly effective, as they could successfully amplify all the major clades of Chinese amphibians in our study. A few non-amphibian taxa were also amplified by these primers, which implies that further optimization of amphibian-specific primers is still needed. The simultaneous use of three primer sets can completely cover all the species obtained by conventional survey methods and has even effectively distinguished quite a number of species (n = 20) in the Wenshan National Nature Reserve. No single primer set could individually detect all of the species from the studied region, indicating that multiple primers might be necessary for a comprehensive survey of Chinese amphibians. Besides, seasonal variations in amphibian species composition were also revealed by eDNA metabarcoding, which was consistent with traditional survey methods. These results indicate that eDNA metabarcoding has the potential to be a powerful tool for studying spatial and temporal community changes in amphibian species richness.

2.
J Infect Dev Ctries ; 18(4): 618-626, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38728647

RESUMO

INTRODUCTION: Hepatitis B virus (HBV) infection is a global epidemic that can lead to several liver diseases, seriously affecting people's health. This study aimed to investigate the clinical potential of serum ß-klotho (KLB) as a promising biomarker in HBV-related liver diseases. METHODOLOGY: This study enrolled 30 patients with chronic hepatitis B (CHB), 35 with HBV-related cirrhosis, 66 with HBV-related hepatocellular carcinoma (HCC), and 48 healthy individuals. ELISA measured the levels of serum KLB in the four groups. We then compared the differences in serum KLB levels among the groups and analyzed the relationship between serum KLB and routine clinical parameters. RESULTS: The concentrations of serum KLB levels were increased sequentially among the healthy subjects, the HBV-related CHB group, the HBV-related cirrhosis group, and the HBV-related HCC group (p < 0.05). Expression of KLB was positively correlated with alpha-fetoprotein (AFP), total bilirubin, direct bilirubin, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl-transferase, alkaline phosphatase, total bile acid, serum markers for liver fibrosis, ascites, cirrhosis, splenomegaly, and model for end-stage liver disease sodium, while negatively correlated with platelet count, albumin, and prothrombin activity (p < 0.05). In addition, serum KLB has better sensitivity in diagnosing HCC than AFP, and serum KLB combined with AFP has higher sensitivity and specificity than AFP alone in diagnosing HCC. CONCLUSIONS: Serum KLB level is associated with the severity of HBV-related liver diseases and has important diagnostic value for HCC. Therefore, it could be a predictive biomarker for monitoring disease progression.


Assuntos
Biomarcadores , Carcinoma Hepatocelular , Hepatite B Crônica , Proteínas Klotho , Humanos , Masculino , Feminino , Biomarcadores/sangue , Pessoa de Meia-Idade , Adulto , Hepatite B Crônica/sangue , Hepatite B Crônica/complicações , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/virologia , Glucuronidase/sangue , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/virologia , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Cirrose Hepática/virologia , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Idoso
3.
J Dig Dis ; 25(3): 191-199, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38697920

RESUMO

OBJECTIVE: To compare the detection rate and diagnostic accuracy of cardia polyps using endoscopy with blue laser imaging (BLI) and white-light imaging (WLI). METHODS: Patients were randomly divided into the BLI group and WLI group according to the endoscopic procedures. BLI followed by WLI was conducted in the BLI group, whereas WLI followed by BLI examination was conducted in the WLI group. The number, size, microstructure, and microvascular patterns of cardia polyps detected were recorded. Biopsy of the polyps was then performed. RESULTS: The detection rate of cardia polyps in the BLI group was higher than that in the WLI group (7.87% vs 4.22%, P = 0.018). The rate of overlooked lesions in the BLI group was lower than in the WLI group (0.64% vs 3.38%, P = 0.003). The diagnostic coincidence rate between magnifying BLI and histopathology was 88.16%. The sensitivity, specificity, positive predictive value and negative predictive value for the diagnosis of neoplastic lesions by magnifying endoscopy with BLI were 90.91%, 87.69%, 55.56%, and 98.28%, respectively. The most remarkable patterns for predicting inflammatory polyps were the prolonged and fine network patterns (sensitivity 71.43%, specificity 93.75%). Small round combined with honeycomb patterns were the most common among fundic gland polyps (sensitivity 80.00%, specificity 98.48%). Neoplastic lesions presented as villous or ridge-like combined with core vascular or unclear pattern for both microvascular and microstructure patterns. CONCLUSION: BLI is more effective than WLI in the detection and diagnosis of cardia polyps, and magnifying endoscopy with BLI may help diagnose such lesions.


Assuntos
Cárdia , Estudos de Viabilidade , Neoplasias Gástricas , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Cárdia/patologia , Cárdia/diagnóstico por imagem , Adulto , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Idoso , Pólipos/diagnóstico por imagem , Pólipos/diagnóstico , Gastroscopia/métodos , Sensibilidade e Especificidade , Valor Preditivo dos Testes , Lasers
4.
ACS Nano ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717846

RESUMO

P3-layered transition oxide cathodes have garnered considerable attention owing to their high initial capacity, rapid Na+ kinetics, and less energy consumption during the synthesis process. Despite these merits, their practical application is hindered by the substantial capacity degradation resulting from unfavorable structural transformations, Mn dissolution and migration. In this study, we systematically investigated the failure mechanisms of P3 cathodes, encompassing Mn dissolution, migration, and the irreversible P3-O3' phase transition, culminating in severe structural collapse. To address these challenges, we proposed an interfacial spinel local interlocking strategy utilizing P3/spinel intergrowth oxide as a proof-of-concept material. As a result, P3/spinel intergrowth oxide cathodes demonstrated enhanced cycling performance. The effectiveness of suppressing Mn migration and maintaining local structure of interfacial spinel local interlocking strategy was validated through depth-etching X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and in situ synchrotron-based X-ray diffraction. This interfacial spinel local interlocking engineering strategy presents a promising avenue for the development of advanced cathode materials for sodium-ion batteries.

6.
Sci Adv ; 10(18): eadn3448, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701211

RESUMO

Despite the physiological and pathophysiological significance of microenvironmental gradients, e.g., for diseases such as cancer, tools for generating such gradients and analyzing their impact are lacking. Here, we present an integrated microfluidic-based workflow that mimics extracellular pH gradients characteristic of solid tumors while enabling high-resolution live imaging of, e.g., cell motility and chemotaxis, and preserving the capacity to capture the spatial transcriptome. Our microfluidic device generates a pH gradient that can be rapidly controlled to mimic spatiotemporal microenvironmental changes over cancer cells embedded in a 3D matrix. The device can be reopened allowing immunofluorescence analysis of selected phenotypes, as well as the transfer of cells and matrix to a Visium slide for spatially resolved analysis of transcriptional changes across the pH gradient. This workflow is easily adaptable to other gradients and multiple cell types and can therefore prove invaluable for integrated analysis of roles of microenvironmental gradients in biology.


Assuntos
Neoplasias , Fenótipo , Microambiente Tumoral , Humanos , Neoplasias/patologia , Neoplasias/metabolismo , Neoplasias/genética , Linhagem Celular Tumoral , Movimento Celular , Concentração de Íons de Hidrogênio , Quimiotaxia , Técnicas Analíticas Microfluídicas
7.
Phytochemistry ; 223: 114113, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38697241

RESUMO

Eleven undescribed cembrane-type diterpenoids, named litoamentenes A-K (1-11), were isolated from the soft coral Litophyton amentaceum collected from the South China Sea. Their structures were elucidated by extensive analysis of spectroscopic data, comparison with the literature data, single crystal X-ray diffraction, quantum chemical calculations and TDDFT-ECD calculations. This is the first systematic investigation of L. amentaceum. In particular, compounds 1-3 are cembrane-type norditerpenoids that lack isopropyl side chains. Compound 6 is a cembrane-type norditerpenoid without a methyl group at C-4, the first natural product identified with this carbon skeleton. Compounds 6, 9 and 10 showed modest cytotoxicity against several human cancer cell lines with IC50 values ranging from 3.99 to 14.56 µM.

8.
Cancer Lett ; 591: 216897, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38631664

RESUMO

Small extracellular vesicles (sEVs) residing at tumor tissues are valuable specimens for biopsy. Tumor heterogeneity is common across all cancer types, but the heterogeneity of tumor tissue-derived sEVs (Ti-sEVs) is undefined. This study aims to discover the spatial distributions of Ti-sEVs in oral squamous cell carcinoma (OSCC) tissues and explore how these vesicle distributions affect the patients' prognosis. Multi-regional sampling enabled us to uncover that Ti-sEVs' accumulation at peritumoral sites correlates with a higher disease-free survival rate, and conversely, sparse peritumoral Ti-sEVs tend to forecast a higher risk of relapse. Of those relapsed patients, Ti-sEVs strongly bind to extracellular matrix and subsequently degrade it for allowing themselves enter the bloodstream rather than staying in situ. In advanced OSCC patients, the quantity and spatial distribution of Ti-sEVs prior to anti-PD-1 treatment, as well as the temporal variance of Ti-sEVs before and after immunotherapy, strongly map the clinical response and can help to distinguish the patients with shrinking tumors from those with growing tumors. Our work elucidates the correlation of spatiotemporal features of Ti-sEVs with patients' therapeutic outcomes and exhibit the potential for using Ti-sEVs as a predictor to forecast prognosis and screen the responders to anti-PD-1 therapy.

9.
J Int Med Res ; 52(4): 3000605241244763, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38656272

RESUMO

A high systolic/diastolic (S/D) ratio of umbilical cord blood is a manifestation of intrauterine hypoxia. However, the clinical significance of a persistently decreased S/D ratio of umbilical cord blood has not been reported. We report eight cases of a persistently decreased S/D ratio of umbilical cord blood, with two cases of umbilical thrombus, five cases of excessive torsion, and one case of a true cord knot. Fetuses with a persistently decreased S/D ratio of umbilical cord blood may be at risk, and it may be an important indication of umbilical cord lesions.


Assuntos
Diástole , Sangue Fetal , Cordão Umbilical , Adulto , Feminino , Humanos , Masculino , Gravidez , Hipóxia Fetal/diagnóstico , Hipóxia Fetal/fisiopatologia , Sístole/fisiologia , Trombose/diagnóstico , Ultrassonografia Pré-Natal , Cordão Umbilical/patologia
10.
Signal Transduct Target Ther ; 9(1): 96, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38653754

RESUMO

The translocation of YAP from the cytoplasm to the nucleus is critical for its activation and plays a key role in tumor progression. However, the precise molecular mechanisms governing the nuclear import of YAP are not fully understood. In this study, we have uncovered a crucial role of SOX9 in the activation of YAP. SOX9 promotes the nuclear translocation of YAP by direct interaction. Importantly, we have identified that the binding between Asp-125 of SOX9 and Arg-124 of YAP is essential for SOX9-YAP interaction and subsequent nuclear entry of YAP. Additionally, we have discovered a novel asymmetrical dimethylation of YAP at Arg-124 (YAP-R124me2a) catalyzed by PRMT1. YAP-R124me2a enhances the interaction between YAP and SOX9 and is associated with poor prognosis in multiple cancers. Furthermore, we disrupted the interaction between SOX9 and YAP using a competitive peptide, S-A1, which mimics an α-helix of SOX9 containing Asp-125. S-A1 significantly inhibits YAP nuclear translocation and effectively suppresses tumor growth. This study provides the first evidence of SOX9 as a pivotal regulator driving YAP nuclear translocation and presents a potential therapeutic strategy for YAP-driven human cancers by targeting SOX9-YAP interaction.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Núcleo Celular , Fatores de Transcrição SOX9 , Fatores de Transcrição , Proteínas de Sinalização YAP , Humanos , Proteínas de Sinalização YAP/genética , Proteínas de Sinalização YAP/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/genética , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Transporte Ativo do Núcleo Celular/genética , Camundongos , Linhagem Celular Tumoral , Animais , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
11.
Cell Signal ; 120: 111187, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38648894

RESUMO

Hypobaric hypoxia, commonly experienced at elevated altitudes, presents significant physiological challenges. Our investigation is centered on the impact of the bromodomain protein 4 (BRD4) under these conditions, especially its interaction with the Wnt/ß-Catenin pathway and resultant effects on glycolytic inflammation and intestinal barrier stability. By combining transcriptome sequencing with bioinformatics, we identified BRD4's key role in hypoxia-related intestinal anomalies. Clinical parameters of altitude sickness patients, including serum BRD4 levels, inflammatory markers, and barrier integrity metrics, were scrutinized. In vitro studies using CCD 841 CoN cells depicted expression changes in BRD4, Interleukin (IL)-1ß, IL-6, and ß-Catenin. Transepithelial electrical resistance (TEER) and FD4 analyses assessed barrier resilience. Hypoxia-induced mouse models, analyzed via H&E staining and Western blot, provided insights into barrier and protein alterations. Under hypoxic conditions, marked BRD4 expression variations emerged. Elevated serum BRD4 in patients coincided with intensified Wnt signaling, inflammation, and barrier deterioration. In vitro, findings showed hypoxia-induced upregulation of BRD4 and inflammatory markers but a decline in Occludin and ZO1, affecting barrier strength-effects mitigated by BRD4 inhibition. Mouse models echoed these patterns, linking BRD4 upregulation in hypoxia to barrier perturbations. Hypobaric hypoxia-induced BRD4 upregulation disrupts the Wnt/ß-Catenin signaling, sparking glycolysis-fueled inflammation and weakening intestinal tight junctions and barrier degradation.

12.
Mol Biotechnol ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664305

RESUMO

This study aimed to investigate the mechanisms of LACTB2 in colorectal cancer (CRC). Microarrays and sequencing data of CRC were acquired from UCSC Xena, GTEx, Gene Expression Omnibus, and TCGA. Pooled analysis of the mRNA expression of LACTB2 in CRC was performed using Stata software. The protein expression of LACTB2 in CRC tissues was evaluated by immunohistochemistry. The relationship between immune cell infiltration and LACTB2 expression was investigated using CIBERSORT. The potential signaling pathways and biological mechanisms of LACTB2 were explored using GSEA, KEGG, and GO. Subsequently, further screening of small molecular compounds with potential therapeutic effects on CRC was conducted through the HERB database, followed by molecular docking studies of these compounds with the LACTB2 protein. The integration and analysis of expression data obtained from 2294 CRC samples and 1286 noncancerous colorectal samples showed that LACTB2 was highly expressed in CRC. Immunohistochemistry performed on in-house tissue samples confirmed that LACTB2 protein expression was upregulated in CRC. CIBERSORT revealed lower B cell infiltration levels in the high LACTB2 expression group than in the low expression group. GO, KEGG, and GSEA analyses showed that LACTB2 expression and genes positively correlating with it were mainly related to DNA synthesis and repair, mitochondrial translational elongation and translational termination, phosphorylation, and mTORC1 signaling. Finally, molecular docking simulations confirmed the ability of quercitin to target and bind to LACTB2. This is the first study to demonstrate that LACTB2 is upregulated in CRC. LACTB2 promotes colorectal tumorigenesis and tumor progression.

13.
Front Med (Lausanne) ; 11: 1337669, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38651056

RESUMO

The tracheal Y-shaped stent is mainly used for the treatment of critical patients with airway stenosis or esophagotracheal fistula near carina. A novel method for precise implantation of Y-shaped tracheal stents was developed using double-lumen endotracheal intubation and flexible bronchoscopy. This approach aims to address the limitations associated with X-ray or rigid bronchoscopy guidance, such as operational difficulties and the risk of inaccurate stent placement leading to implantation failure or suffocation. With this new technique, 13 tracheal Y-shaped stents were successfully implanted. This method shows promise in reducing the complexity of stent implantation and facilitating timely treatment for patients in need. Additionally, it has the potential to update current operating standards and guidelines for this procedure.

14.
Adv Sci (Weinh) ; : e2309461, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671588

RESUMO

Unlike bulky and rigid traditional power systems, 1D fiber batteries possess appealing features such as flexibility and adaptability, which are promising for use in wearable electronic devices. However, the performance and energy density fiber batteries are limited by the contradiction between ionic transfer and robust structure of fiber electrodes. Herein, these problems are addressed via polymer engineering to regulate the microenvironment in electrodes, realizing high-linear-capacity thick fiber electrodes with excellent cycling performance. The porosity of the electrodes is regulated using polymer crosslink networks designed with various components, and lithium-ion transfer is optimized through ether-abundant polymer chains. Furthermore, reinforced covalent bonding with carbon nanotube networks is established based on the modified functional groups of polymer networks. The multiscale optimizations of the porous structure, ionic transportation, and covalent bonding network enhance the lithium-ion dynamics property and structural stability. Therefore, ultrahigh linear-capacity fiber electrodes (17.8 mAh m-1) can be fabricated on a large scale and exhibit excellent stability (92.8% after 800 cycles), demonstrating obvious superiority among the reported fiber electrodes. Moreover, this study highlights the high effectiveness of polymer regulation in fiber electrodes and offers new avenues for designing next-generation wearable energy-storage systems.

15.
Pharmacol Res ; 203: 107168, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583689

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disease characterized by progressive loss of dopaminergic neurons in the substantia nigra and the aggregation of alpha-synuclein (α-syn). The central nervous system (CNS) has previously been considered as an immune-privileged area. However, studies have shown that the immune responses are involved in PD. The major histocompatibility complex (MHC) presents antigens from antigen-presenting cells (APCs) to T lymphocytes, immune responses will be induced. MHCs are expressed in microglia, astrocytes, and dopaminergic neurons. Single nucleotide polymorphisms in MHC are related to the risk of PD. The aggregated α-syn triggers the expression of MHCs by activating glia cells. CD4+ and CD8+ T lymphocytes responses and microglia activation are detected in brains of PD patients. In addiction immune responses further increase blood-brain barrier (BBB) permeability and T cell infiltration in PD. Thus, MHCs are involved in PD through participating in immune and inflammatory responses.


Assuntos
Complexo Principal de Histocompatibilidade , Doença de Parkinson , Humanos , Doença de Parkinson/imunologia , Doença de Parkinson/genética , Animais , Complexo Principal de Histocompatibilidade/imunologia , alfa-Sinucleína/imunologia , alfa-Sinucleína/metabolismo , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/metabolismo , Microglia/imunologia , Microglia/metabolismo
16.
Chemistry ; : e202304234, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644695

RESUMO

With both TEMPO and O2 (in air) as the homogeneous redox mediators, BiBrO as the heterogeneous semiconductor photocatalyst, the first example of semi-heterogeneous photocatalytic decarboxylative phosphorylation of N-arylglycines with diarylphosphine oxides was established. A series of α-amino phosphinoxides were efficiently synthesized.

18.
Huan Jing Ke Xue ; 45(5): 2891-2904, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629551

RESUMO

The increasing use of nitrogen fertilizers exerts extreme pressure on the environment (e.g., greenhouse gas emissions, GHGs) for winter wheat-summer maize rotation systems in the North China Plain. The application of controlled-release fertilizers is considered as an effective measure to improve crop yield and nitrogen fertilizer utilization efficiency. To explore the impact of one-time fertilization of controlled-release blended fertilizer on crop yield and GHGs of a wheat-maize rotation system, field experiments were carried out in Dezhou Modern Agricultural Science and Technology Park from 2020 to 2022. Five treatments were established for both winter wheat and summer maize, including no nitrogen control (CK), farmers' conventional nitrogen application (FFP), optimized nitrogen application (OPT), CRU1 (the blending ratio of coated urea and traditional urea on winter wheat and summer maize was 5:5 and 3:7, respectively), and CRU2 (the blending ratio of coated urea and traditional urea on winter wheat and summer maize was 7:3 and 5:5, respectively). The differences in yield, nitrogen fertilizer utilization efficiency, fertilization economic benefits, and GHGs among different treatments were compared and analyzed. The results showed that nitrogen application significantly increased the single season and annual crop yields of the wheat-maize rotation system (P < 0.05). Compared with those of FFP, the CRU1 and CRU2 treatments increased the yields of summer maize by 0.4% to 5.6%, winter wheat by -5.4% to 4.1%, and annual yields by -1.1% to 3.9% (P > 0.05). N recovery efficiency (NRE), N agronomic efficiency (NAE), and N partial factor productivity (NPFP) were increased by -8.6%-43.4%, 2.05-6.24 kg·kg-1, and 4.24-10.13 kg·kg-1, respectively. Annual net income increased by 0.2% to 6.3%. Nitrogen application significantly increased the annual emissions of soil N2O and CO2 in the rotation system (P < 0.05) but had no effect on the annual emissions of CH4 (except for in the FFP treatment in the first year). The annual total N2O emissions under the CRU1 and CRU2 treatments were significantly reduced by 23.4% to 30.2% compared to those under the FFP treatment (P < 0.05). Additionally, nitrogen application significantly increased the annual global warming potential (GWP) of the rotation system (P < 0.05), but the intensity of greenhouse gas emissions was reduced due to the increase in crop yields. Compared with that under FFP, the annual GWP under the CRU1 and CRU2 treatments decreased by 9.6% to 11.5% (P < 0.05), and the annual GHGs decreased by 11.2% to 13.8% (P > 0.05). In summary, the one-time application of controlled-release blended fertilizer had a positive role in improving crop yield and economic benefits, reducing nitrogen fertilizer input and labor costs, and GHGs, which is an effective nitrogen fertilizer management measure to promote cleaner production of food crops in the North China Plain.


Assuntos
Gases de Efeito Estufa , Fertilizantes , Triticum , Zea mays , Preparações de Ação Retardada , Óxido Nitroso/análise , Agricultura/métodos , Solo , China , Nitrogênio , Ureia
19.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1526-1539, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621936

RESUMO

This study aims to investigate the component variations and spatial distribution of ginsenosides in Panax quinquefolium roots during repeated steaming and drying. Ultra performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS/MS) was employed to identify the ginsenosides in the root extract. Matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI) was employed to visualize the spatial distribution and spatiotemporal changes of prototype ginsenosides and metabolites in P. quinquefolium roots. The UPLC results showed that 90 ginsenosides were identified during the steaming process of the roots, and polar ginsenosides were converted into low polar or non-polar ginsenosides. The content of prototype ginsenosides decreased, while that of rare ginsenosides increased, which included 20(S/R)-ginsenoside Rg_3, 20(S/R)-ginsenoside Rh_2, and ginsenosides Rk_1, Rg_5, Rs_5, and Rs_4. MALDI-MSI results showed that ginsenosides were mainly distributed in the epidermis and phloem. As the steaming times increased, ginsenosides were transported to the xylem and medulla. This study provides fundamental information for revealing the changes of biological activity and pharmacological effect of P. quinquefolium roots that are caused by repeated steaming and drying and gives a reference for expanding the application scope of this herbal medicine.


Assuntos
Ginsenosídeos , Panax , Ginsenosídeos/análise , Espectrometria de Massas em Tandem , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Panax/química , Cromatografia Líquida de Alta Pressão/métodos , Raízes de Plantas/química
20.
Chem Sci ; 15(14): 5192-5200, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38577355

RESUMO

Layered transition metal oxides (NaxTMO2) possess attractive features such as large specific capacity, high ionic conductivity, and a scalable synthesis process, making them a promising cathode candidate for sodium-ion batteries (SIBs). However, NaxTMO2 suffer from multiple phase transitions and Na+/vacancy ordering upon Na+ insertion/extraction, which is detrimental to their electrochemical performance. Herein, we developed a novel cathode material that exhibits an abnormal P2-type structure at a stoichiometric content of Na up to 1. The cathode material delivers a reversible capacity of 108 mA h g-1 at 0.2C and 97 mA h g-1 at 2C, retaining a capacity retention of 76.15% after 200 cycles within 2.0-4.3 V. In situ diffraction studies demonstrated that this material exhibits an absolute solid-solution reaction with a low volume change of 0.8% during cycling. This near-zero-strain characteristic enables a highly stabilized crystal structure for Na+ storage, contributing to a significant improvement in battery performance. Overall, this work presents a simple yet effective approach to realizing high Na content in P2-type layered oxides, offering new opportunities for high-performance SIB cathode materials.

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