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1.
Phytochemistry ; 217: 113900, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37898415

RESUMO

A phytochemical research on the twigs of Dichapetalum longipetalum (Turcz.) Engl. Resulted in five undescribed dichapetalin-type triterpenoids 1-5. Their chemical structures were determined by spectroscopic analysis of HR-ESIMS and NMR spectra and the absolute configuration of compound 1 was completely elucidated by single crystal X-ray crystallography. Through preliminary anti-inflammatory activity assessment, compound 1 exhibited inhibitory effect on LPS-induced NO production in RAW264.7 murine macrophages with an IC50 value of 2.09 µM.


Assuntos
Triterpenos , Animais , Camundongos , Triterpenos/farmacologia , Triterpenos/química , Macrófagos , Extratos Vegetais/química , Espectroscopia de Ressonância Magnética , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Estrutura Molecular
2.
Urol Int ; 107(9): 841-847, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37769625

RESUMO

BACKGROUND: Tertiary lymphoid structures (TLSs), as ectopic lymphoid-like tissues, are highly similar to secondary lymphoid organs and are not only involved in chronic inflammation and autoimmune responses but are also closely associated with tumor immunotherapy and prognosis. The complex composition of the urological tumor microenvironment not only varies greatly in response to immunotherapy, but the prognostic value of TLSs in different urological tumors remains controversial. SUMMARY: We searched PubMed, Web of Science, and other full-text database systems. TLSs, kidney cancer, uroepithelial cancer, bladder cancer, and prostate cancer as keywords, relevant literature was searched from the time the library was built to 2023. Systematically explore the role and mechanism of TLSs in urological tumors. It includes the characteristics of TLSs, the role and mechanism of TLSs in urological tumors, and the clinical significance of TLSs in urological tumors. KEY MESSAGES: The prognostic role of TLSs in different urological tumors was significantly different. It is not only related to its enrichment in the tumor but also highly correlated with the location of the tumor. In addition, autoimmune toxicity may be a potential barrier to its role in the formation of TLSs through induction. Therefore, studying the mechanisms of TLSs in autoimmune diseases may help in the development of antitumor target drugs.


Assuntos
Neoplasias Renais , Neoplasias da Próstata , Estruturas Linfoides Terciárias , Neoplasias da Bexiga Urinária , Neoplasias Urológicas , Masculino , Humanos , Prognóstico , Estruturas Linfoides Terciárias/patologia , Neoplasias Urológicas/terapia , Neoplasias da Bexiga Urinária/terapia , Neoplasias Renais/terapia , Microambiente Tumoral
3.
Chem Rev ; 122(3): 3820-3878, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-34939420

RESUMO

With the development of advanced electronic devices and electric power systems, polymer-based dielectric film capacitors with high energy storage capability have become particularly important. Compared with polymer nanocomposites with widespread attention, all-organic polymers are fundamental and have been proven to be more effective choices in the process of scalable, continuous, and large-scale industrial production, leading to many dielectric and energy storage applications. In the past decade, efforts have intensified in this field with great progress in newly discovered dielectric polymers, fundamental production technologies, and extension toward emerging computational strategies. This review summarizes the recent progress in the field of energy storage based on conventional as well as heat-resistant all-organic polymer materials with the focus on strategies to enhance the dielectric properties and energy storage performances. The key parameters of all-organic polymers, such as dielectric constant, dielectric loss, breakdown strength, energy density, and charge-discharge efficiency, have been thoroughly studied. In addition, the applications of computer-aided calculation including density functional theory, machine learning, and materials genome in rational design and performance prediction of polymer dielectrics are reviewed in detail. Based on a comprehensive understanding of recent developments, guidelines and prospects for the future development of all-organic polymer materials with dielectric and energy storage applications are proposed.

4.
Adv Mater ; 33(34): e2008267, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34240474

RESUMO

Recently, sensors that can imitate human skin have received extensive attention. Capacitive sensors have a simple structure, low loss, no temperature drift, and other excellent properties, and can be applied in the fields of robotics, human-machine interactions, medical care, and health monitoring. Polymer matrices are commonly employed in flexible capacitive sensors because of their high flexibility. However, their volume is almost unchanged when pressure is applied, and they are inherently viscoelastic. These shortcomings severely lead to high hysteresis and limit the improvement in sensitivity. Therefore, considerable efforts have been applied to improve the sensing performance by designing different microstructures of materials. Herein, two types of sensors based on the applied forces are discussed, including pressure sensors and strain sensors. Currently, five types of microstructures are commonly used in pressure sensors, while four are used in strain sensors. The advantages, disadvantages, and practical values of the different structures are systematically elaborated. Finally, future perspectives of microstructures for capacitive sensors are discussed, with the aim of providing a guide for designing advanced flexible and stretchable capacitive sensors via ingenious human-made microstructures.


Assuntos
Técnicas Biossensoriais/instrumentação , Dispositivos Eletrônicos Vestíveis , Animais , Capacitância Elétrica , Impedância Elétrica , Desenho de Equipamento , Humanos , Monitorização Ambulatorial/instrumentação , Polímeros , Pressão , Robótica , Pele , Temperatura , Têxteis , Interface Usuário-Computador
5.
Macromol Rapid Commun ; 42(12): e2100116, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33938056

RESUMO

Polymer-based film capacitors with high breakdown strength and excellent flexibility are crucial in the field of advanced electronic devices and electric power systems. Although massive works are carried to enhance the energy storage performances, it is still a great challenge to improve the energy density of polymer composites under the premise of large-scale industrial production. Herein, a general strategy is proposed to improve the intrinsic breakdown strength and energy storage performances by blending core-shell structured methyl methacrylate-butadiene-styrene (MBS) rubber particles into a polymer matrix. Good compatibility and uniform dispersion state of MBS particles are observed in the matrix. Polarizing microscopy images show that blended films exhibit clear reduction of crystalline grains with the addition of MBS particles. Accordingly, an increased breakdown strength of 515 MV m-1 and discharged energy density of 12.33 J cm-3 are observed in poly(vinylidene fluoride-co-hexafluoropropylene)-based composite films. Through comprehensive characterizations, it is believed that the superior energy storage performance of composite films is attributed to decreased crystalline grains, improved mechanical properties, and restriction on carrier motion. These results provide a novel design of dielectric polymers for high breakdown strength and discharged energy density applications.


Assuntos
Eletricidade , Polímeros
6.
J Nat Prod ; 84(5): 1556-1562, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33914536

RESUMO

Longipetalol A (1) is an unprecedented highly modified triterpenoid with a unique 1,2-seco-3-(2-oxo-phenylethyl)-17α-13,30-cyclodammarane skeleton, featuring an acetal-lactone fragment. It was isolated from Dichapetalum longipetalum along with two additional derivatives, namely, longipetalols B (2) and C (3). Their structures were elucidated using spectroscopic analyses combined with single-crystal X-ray diffraction. Compounds 1, 2, and 3 exhibited inhibitory effects on nitric oxide production in lipopolysaccharide-induced RAW264.7 macrophages.


Assuntos
Anti-Inflamatórios/farmacologia , Magnoliopsida/química , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , China , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Fitoquelatinas/isolamento & purificação , Fitoquelatinas/farmacologia , Células RAW 264.7 , Triterpenos/isolamento & purificação
7.
Fitoterapia ; 151: 104868, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33652077

RESUMO

Nine previously undescribed dichapetalin-type triterpenoids (1-9), along with 12 reported compounds (10-21), were isolated from the twigs of Dichapetalum gelonioides. Their chemical structures were mainly elucidated by comprehensive analysis of HRMS, 1D and 2D NMR spectroscopic data. The absolute configuration of compound 1 was further determined based on single-crystal X-ray diffraction. In addition, a part of compounds were evaluated the effects of inhibitory NO production in LPS-induced RAW264.7 macrophages.


Assuntos
Anti-Inflamatórios/farmacologia , Malpighiales/química , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , China , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Células RAW 264.7 , Triterpenos/isolamento & purificação
8.
Scand J Immunol ; 91(2): e12843, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31657484

RESUMO

Inflammatory bowel disease (IBD) is a chronic, non-specific, inflammatory gastrointestinal disease that mainly consists of Crohn's disease and ulcerative colitis. However, the aetiology and pathogenesis of IBD are still unclear. B10 (IL-10 producing regulatory B) cells, a subset of regulatory B cells, are known to contribute to intestinal homeostasis and the aberrant frequency of B10 cells is associated with IBD. We have recently reported that B10 cells can be induced by ManLAM (mannose-capped lipoarabinomannan), a major cell-wall lipoglycan of M tb (Mycobacterium tuberculosis). In the current study, the ManLAM-induced B10 cells were adoptively transferred into IL(interleukin)-10-/- mice and the roles of ManLAM-induced B10 cells were investigated in DSS (dextran sodium sulphate)-induced IBD model. ManLAM-induced B10 cells decrease colitis severity in the mice. The B10 cells downregulate Th1 polarization in spleen and MLNs (mesenteric lymph nodes) of DSS-treated mice. These results suggest that IL-10 production by ManLAM-treated B cells contributes to keeping the balance between CD4+ T cell subsets and protect mice from DSS-induced IBD.


Assuntos
Linfócitos B Reguladores/imunologia , Doenças Inflamatórias Intestinais/imunologia , Interleucina-10/metabolismo , Lipopolissacarídeos/metabolismo , Manose/metabolismo , Mycobacterium tuberculosis/metabolismo , Células Th1/imunologia , Animais , Sulfato de Dextrana , Modelos Animais de Doenças , Humanos , Tolerância Imunológica , Doenças Inflamatórias Intestinais/induzido quimicamente , Lipopolissacarídeos/imunologia , Manose/imunologia , Camundongos , Camundongos Knockout
9.
Artigo em Inglês | MEDLINE | ID: mdl-28993192

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

10.
Int J Clin Exp Pathol ; 10(8): 8686-8694, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31966726

RESUMO

Cancer-related systemic inflammation affects many aspects of malignancy. The platelet-to-lymphocyte ratio (PLR), an easily applicable inflammatory marker based on platelet and lymphocyte counts, is associated with the clinical outcome of some cancers. The present study aimed to investigate the prognostic significance of the preoperative PLR in a cohort of colorectal cancer (CRC) patients. A total of 138 patients with CRC were enrolled in this retrospective study. The optimal cutoff value for the PLR was calculated using receiver operating curve (ROC) analysis. The correlation of PLR with the clinicopathological characteristics of patients was explored. Cox proportional hazard analysis was applied to determine the independent prognostic effect of PLR. PLR of 248 yielded the most optimal predictive value for the prognosis of CRC [area under the curve (AUC) = 0.820]. High level of PLR was significantly associated with lymph node and distance metastasis (P<0.001 and = 0.003, respectively), vascular and perinural invasion (P<0.001), advanced TNM stage (P<0.001), and poor differentiation (P = 0.037). Furthermore, the univariable analysis showed a significant impact of increased PLR on OS (HR = 4.326, 95% CI: 2.903-6.445, P<0.001), while this association remained significant in multivariable analysis (adjusted HR = 4.605, 95% CI: 2.786-7.611, P<0.001). Our findings indicated that elevated preoperative PLR might have potential value in predicting poor outcome in patients with CRC.

11.
Electrophoresis ; 31(17): 2989-96, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20680970

RESUMO

A novel method of CE coupled with dual electrochemical detection has been developed for the determination of pathological metabolites of phenylalanine in urine samples. Factors influencing the separation and detection were examined and optimized. Five aromatic acid metabolites and a major coexisting interfering compound uric acid could be well separated within 23 min at a separation voltage of 16 kV using a 35 mmol/L SDS/60 mmol/L H(3)BO(3)-Na(2)B(4)O(7) running buffer (pH 8.2). Highly linear response was obtained for these five biomarker compounds over three orders of magnitude with detection limits ranging from 6.6 to 0.064 µg/mL (S/N=3). The average recovery and RSD were within the range of 92.6-121.0 and 1.0-12.0%, respectively. The proposed method has been used to detect the unconjugated aromatic acids simultaneously in urine samples with the advantages of obtaining more information about target analytes and avoiding redundant measurements and high assay cost, thus could find potential applications involving assays of biomarker compounds for the purpose of fast diagnose of some metabolic diseases including phenylketonuria.


Assuntos
Biomarcadores/urina , Eletroforese Capilar/métodos , Fenilacetatos/urina , Fenilcetonúrias , Ácidos Fenilpirúvicos/urina , Adulto , Eletrodos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Lactente , Modelos Lineares , Masculino , Fenilalanina/metabolismo , Fenilcetonúrias/diagnóstico , Fenilcetonúrias/urina , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Dodecilsulfato de Sódio
12.
Neurosci Bull ; 25(3): 131-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19448687

RESUMO

OBJECTIVE: This report aims to describe the oxidative damage profile in brain of presenilin1 and presenilin2 conditional double knockout mice (dKO) at both early and late age stages, and to discuss the correlation between oxidative stress and the Alzheimer-like phenotypes of dKO mice. METHODS: The protein level of Abeta(42) in dKO cortex and free 8-OHdG level in urine were measured by ELISA. Thiobarbituric acid method and spectrophotometric DNPH assay were used to determine the lipid peroxidation and protein oxidation in cortex, respectively. SOD and GSH-PX activities were assessed by SOD Assay Kit-WST and GSH-PX assay kit, separately. RESULTS: Significant decrease of Abeta(42) was verified in dKO cortex at 6 months as compared to control mice. Although lipid peroxidation (assessed by MDA) was increased only in dKO cortex at 3 months and protein oxidation (assessed by carbonyl groups) was basically unchanged in dKO cortex, ELISA analysis revealed that free 8-OHdG, which was an indicator of DNA lesion, was significantly decreased in urine of dKO mice from 3 months to 12 months. Activities of SOD and GSH-PX in dKO and control cortices showed no statistical difference except a significant increase of GSH-PX activity in dKO mice at 9 months. CONCLUSION: Oxidative damage, especially DNA lesion, was correlated with the neurodegenerative symptoms that appeared in dKO mice without the deposition of Abeta(42). Triggers of oxidative damage could be the inflammatory mediators released by activated microglia and astrocytes.


Assuntos
Doença de Alzheimer/fisiopatologia , Camundongos Knockout/fisiologia , Estresse Oxidativo/fisiologia , Presenilina-1/deficiência , Presenilina-2/deficiência , 8-Hidroxi-2'-Desoxiguanosina , Fatores Etários , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/urina , Animais , Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática/métodos , Glutationa/metabolismo , Hidrazinas/metabolismo , Peroxidação de Lipídeos/genética , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos CBA , Oxirredução , Fragmentos de Peptídeos/urina , Espectrofotometria Atômica/métodos , Superóxido Dismutase/metabolismo
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