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1.
Small ; : e2401767, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847563

RESUMO

Porous graphene, including 2D and 3D porous graphene, is widely researched recently. One of the most attractive features is the proper utilization of graphene defects, which combine the advantages of both graphene and porous materials, greatly enriching the applications of porous graphene in biology, chemistry, electronics, and other fields. In this review, the defects of graphene are first discussed to provide a comprehensive understanding of porous graphene. Then, the latest advancements in the preparation of 2D and 3D porous graphene are presented. The pros and cons of these preparation methods are discussed in detail, providing a direction for the fabrication of porous graphene. Moreover, various superior properties of porous graphene are described, laying the foundation for their promising applications. Owing to its abundant morphology, wide distribution of pore size, and remarkable properties benefited from porous structure, porous graphene can not only promote molecular diffusion and electron transfer but also expose more active sites. Consequently, a serious of applications containing gas sieving, liquid separation, sensors, and supercapacitors, are presented. Finally, the challenges confronted during preparation and characterization of porous graphene are discussed, offering guidance for the future development of porous graphene in fabrication, characterization, properties, and applications.

2.
Small ; 20(22): e2310002, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38109068

RESUMO

2D Ruddlesden-Popper phase layered perovskites (RPLPs) hold great promise for optoelectronic applications. In this study, a series of high-performance heterojunction phototransistors (HPTs) based on RPLPs with different organic spacer cations (namely butylammonium (BA+), cyclohexylammonium (CyHA+), phenethylammonium (PEA+), p-fluorophenylethylammonium (p-F-PEA+), and 2-thiophenethylammonium (2-ThEA+)) are fabricated successfully, in which high-mobility organic semiconductor 2,7-dioctyl[1]benzothieno[3,2-b]benzothiophene is adopted to form type II heterojunction channels with RPLPs. The 2-ThEA+-RPLP-based HPTs show the highest photosensitivity of 3.18 × 107 and the best detectivity of 9.00 × 1018 Jones, while the p-F-PEA+-RPLP-based ones exhibit the highest photoresponsivity of 5.51 × 106 A W-1 and external quantum efficiency of 1.32 × 109%, all of which are among the highest reported values to date. These heterojunction systems also mimicked several optically controllable fundamental characteristics of biological synapses, including excitatory postsynaptic current, paired-pulse facilitation, and the transition from short-term memory to long-term memory states. The device based on 2-ThEA+-RPLP film shows an ultra-high PPF index of 234%. Moreover, spacer engineering brought fine-tuned thin film microstructures and efficient charge transport/transfer, which contributes to the superior photodetection performance and synaptic functions of these RPLP-based HPTs. In-depth structure-property correlations between the organic spacer cations/RPLPs and thin film microstructure/device performance are systematically investigated.

3.
Phys Rev Lett ; 132(19): 197202, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38804947

RESUMO

The higher-order topological phases have attracted intense attention in the past years, which reveals various intriguing topological properties. Meanwhile, the enrichment of group symmetries with projective symmetry algebras redefines the fundamentals of topological matter and makes Stiefel-Whitney (SW) classes in classical wave systems possible. Here, we report the experimental realization of higher-order topological nodal loop semimetal in an acoustic system and obtain the inherent SW topological invariants. In stark contrast to higher-order topological semimetals relating to complex vector bundles, the hinge and surface states in the SW topological phase are protected by two distinctive SW topological charges relevant to real vector bundles. Our findings push forward the studies of SW class topology in classical wave systems, which also show possibilities in robust high-Q-resonance-based sensing and energy harvesting.

4.
Mol Cell Biochem ; 479(7): 1707-1720, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38822192

RESUMO

HOXC6 (Homeobox C6) and methyltransferase-like 3 (METTL3) have been shown to be involved in the progression of prostate cancer (PCa). However, whether HOXC6 performs oncogenic effects in PCa via METTL3-mediated N6-methyladenosine (m6A) modification is not yet reported. The Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, transwell, scratch, sphere formation assays were applied for cell growth, invasion, migration and stemness analyses. Glycolysis was evaluated by measuring glucose consumption, lactate generation and ATP/ADP ratio. The N6-methyladenine (m6A) modification profile was determined by RNA immunoprecipitation (Me-RIP) assay. The proteins that interact with PGK1 (phosphoglycerate kinase 1) were confirmed by Co-immunoprecipitation assay. Tumor formation experiments in mice were conducted for in vivo assay. PCa tissues and cells showed highly expressed HOXC6 and METTL3. Functionally, the silencing of HOXC6 or METTL3 suppresses PCa cell proliferation, invasion, migration, stemness, and glycolysis. Moreover, METTL3-induced HOXC6 m6A modification to stabilize its expression. In addition, the m6A reader IGF2BP2 directly recognized and bound to HOXC6 mRNA, and maintained its stability, and was involved in the regulation of HOXC6 expression by METTL3. Furthermore, IGF2BP2 knockdown impaired PCa cell proliferation, invasion, migration, stemness, and glycolysis by regulating HOXC6. Besides that HOXC6 interacted with the glycoytic enzyme PGK1 in PCa cells. In vivo assays further showed that METTL3 silencing reduced the expression of HOXC6 and PGK1, and impeded PCa growth. METTL3 promoted PCa progression by maintaining HOXC6 expression in an m6A-IGF2BP2-dependent mechanism.


Assuntos
Adenosina , Proteínas de Homeodomínio , Metiltransferases , Neoplasias da Próstata , Proteínas de Ligação a RNA , Metiltransferases/metabolismo , Metiltransferases/genética , Masculino , Humanos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Animais , Camundongos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Progressão da Doença , Fosfoglicerato Quinase/metabolismo , Fosfoglicerato Quinase/genética , Linhagem Celular Tumoral , Glicólise , Movimento Celular , Camundongos Nus
5.
BMC Cardiovasc Disord ; 24(1): 129, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424525

RESUMO

PURPOSE: This study was aimed to identify the risk factors that influence the mortality risk in patients with acute aortic dissection (AAD) within one year after discharge, and aimed to construct a predictive model for assessing mortality risk. METHODS: The study involved 320 adult patients obtained from the Medical Information Mart for Intensive Care (MIMIC) database. Logistic regression analysis was conducted to identify potential risk factors associated with mortality in AAD patients within one year after discharge and to develop a predictive model. The performance of the predictive model was assessed using the receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA). To further validate the findings, patient data from the First Affiliated Hospital of Guangxi Medical University (157 patients) were analyzed. RESULTS: Univariate and multivariate logistic regression analyses revealed that gender, length of hospital stay, highest blood urea nitrogen (BUN_max), use of adrenaline, and use of amiodarone were significant risk factors for mortality within one year after discharge (p < 0.05). The constructed model exhibited a consistency index (C-index) and an area under the ROC curve of 0.738. The calibration curve and DCA demonstrated that these indicators had a good degree of agreement and utility. The external validation results of the model also indicated good predictability (AUC = 0.700, p < 0.05). CONCLUSION: The personalized scoring prediction model constructed by gender, length of hospital stays, BUN_max levels, as well as the use of adrenaline and amiodarone, can effectively identify AAD patients with high mortality risk within one year after discharge.


Assuntos
Amiodarona , Dissecção Aórtica , Adulto , Humanos , Estudos Transversais , Alta do Paciente , China/epidemiologia , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/terapia , Epinefrina , Fatores de Risco , Estudos Retrospectivos
6.
Int Nurs Rev ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477788

RESUMO

AIM: To evaluate the mediating roles of occupational resilience and the moderationg role of perceived organizational support in the relationship between career calling and nurse burnout. BACKGROUND: Burnout is a frequent and serious problem in the field of nursing, and it poses a serious threat to both nurses' health and patient safety. Although many studies have described the links between burnout, career calling, and occupational resilience, little is known about the actual mechanisms between career calling and nurse burnout. METHODS: A cross-sectional study of 615 nurses in China was conducted using a convenience sampling method. The data were analyzed using descriptive statistics and Pearson correlation analysis. Hypotheses were tested using structural equation models and bootstrapping methods. STROBE guidelines were followed. RESULTS: Career calling was found to be negatively associated with nurse burnout, and occupational resilience mediated the relationship between career calling and burnout. Additionally, perceived organizational support was found to play a moderating role in the relationship between occupational resilience and burnout. CONCLUSION: Career calling can reduce burnout by increasing nurses' levels of occupational resilience, and perceived organizational support moderates this mechanism. Hence, policies focused on encouraging and sustaining career calling should be provided by nurse managers in order to enhance stress resistance and reduce burnout.

7.
Zhongguo Zhong Yao Za Zhi ; 49(2): 294-303, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403305

RESUMO

Lung cancer is the leading cause of cancer death, and its effective treatment is a difficult medical problem. Lung cancer belongs to the traditional Chinese medicine(TCM) disease categories of lung accumulation, lung amassment, and overstrain cough. Rich theoretical basis and practical experience have been accumulated in the TCM treatment of lung cancer. Astragali Radix is one of the representatives of Qi-tonifying drugs. It mainly treat the lung cancer with the syndrome of Qi deficiency and pathogen stagnation, following the principle of reinforcing healthy Qi and eliminating patgogenic Qi. Astragali Radix exerts a variety of pharmacological activities in the treatment of lung cancer, including inhibiting tumor cell proliferation and promoting tumor cell apoptosis, inhibiting tumor invasion and migration, regulating the tumor microenvironment, suppressing tumor angiogenesis, modulating autophagy, inducing macrophage polarization, enhancing immunity, inhibiting immune escape, and reversing cisplatin resistance. The active ingredients of Astragali Radix in treating lung cancer include polysaccharides, saponins, and flavonoids. This study reviewed the pharmacological activities and active ingredients of Astragali Radix in the treatment of lung cancer, providing a basis for the development and utilization of Astragali Radix resources and active ingredients and the research and development of anti-tumor drugs.


Assuntos
Astrágalo , Medicamentos de Ervas Chinesas , Neoplasias Pulmonares , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Medicina Tradicional Chinesa , Raízes de Plantas , Microambiente Tumoral
8.
Neurobiol Dis ; 186: 106263, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37591465

RESUMO

The R47H variant of triggering receptor expressed on myeloid cells 2 (TREM2) increases the risk of Alzheimer's disease (AD). To investigate potential mechanisms, we analyzed knockin mice expressing human TREM2-R47H from one mutant mouse Trem2 allele. TREM2-R47H mice showed increased seizure activity in response to an acute excitotoxin challenge, compared to wildtype controls or knockin mice expressing the common variant of human TREM2. TREM2-R47H also increased spontaneous thalamocortical epileptiform activity in App knockin mice expressing amyloid precursor proteins bearing autosomal dominant AD mutations and a humanized amyloid-ß sequence. In mice with or without such App modifications, TREM2-R47H increased the density of putative synapses in cortical regions without amyloid plaques. TREM2-R47H did not affect synaptic density in hippocampal regions with or without plaques. We conclude that TREM2-R47H increases AD-related network hyperexcitability and that it may do so, at least in part, by causing an imbalance in synaptic densities across brain regions.


Assuntos
Doença de Alzheimer , Humanos , Animais , Camundongos , Doença de Alzheimer/genética , Alelos , Convulsões , Peptídeos beta-Amiloides , Modelos Animais de Doenças , Placa Amiloide , Sinapses , Glicoproteínas de Membrana/genética , Receptores Imunológicos/genética
9.
Small ; 19(17): e2207876, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36703526

RESUMO

Covalent organic frameworks (COFs) are a unique new class of porous materials that arrange building units into periodic ordered frameworks through strong covalent bonds. Accompanied with structural rigidity and well-defined geometry, heteroacene-based COFs have natural advantages in constructing COFs with high stability and crystallinity. Heteroacene-based COFs usually have high physical and chemical properties, and their extended π-conjugation also leads to relatively low energy gap, effectively promoting π-electron delocalization between network units. Owing to excellent electron-withdrawing or -donating ability, heteroacene units have incomparable advantages in the preparation of donor-acceptor type COFs. Therefore, the physicochemical robust and fully conjugated heteroacene-based COFs solve the problem of traditional COFs lacking π-π interaction and chemical stability. In recent years, significant breakthroughs are made in this field, the choice of various linking modes and building blocks has fundamentally ensured the final applications of COFs. It is of great significance to summarize the heteroacene-based COFs for improving its complexity and controllability. This review first introduces the linkages in heteroacene-based COFs, including reversible and irreversible linkages. Subsequently, some representative building blocks are summarized, and their related applications are especially emphasized. Finally, conclusion and perspectives for future research on heteroacene-based COFs are presented.

10.
Small ; : e2308019, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057125

RESUMO

Covalent organic frameworks (COFs), a new class of crystalline materials connected by covalent bonds, have been developed rapidly in the past decades. However, the research on COFs is mainly focused on two-dimensional (2D) COFs, and the research on three-dimensional (3D) COFs is still in the initial stage. In 2D COFs, the covalent bonds exist only in the 2D flakes and can form 1D channels, which hinder the charge transport to some extent. In contrast, 3D COFs have a more complex pore structure and thus exhibit higher specific surface area and richer active sites, which greatly enhance the 3D charge carrier transport. Therefore, compared to 2D COFs, 3D COFs have stronger applicability in energy storage and conversion, sensing, and optoelectronics. In this review, it is first introduced the design principles for 3D COFs, and in particular summarize the development of conjugated building blocks in 3D COFs, with a special focus on their application in optoelectronics. Subsequently, the preparation of 3D COF powders and thin films and methods to improve the stability and functionalization of 3D COFs are summarized. Moreover, the applications of 3D COFs in electronics are outlined. Finally, conclusions and future research directions for 3D COFs are presented.

11.
Zhongguo Zhong Yao Za Zhi ; 48(22): 6003-6010, 2023 Nov.
Artigo em Zh | MEDLINE | ID: mdl-38114206

RESUMO

Angelicae Sinensis Radix is one of the main Chinese medicinal materials with both medicinal and edible values. It has the functions of tonifying and activating blood, regulating menstruation and relieving pain, and moistening intestines to relieve constipation. It is mainly produced in the southeastern Gansu province, and that produced in Minxian, Gansu is praised for the best quality. The chemical components of Angelicae Sinensis Radix mainly include volatile oils, organic acids, and polysaccharides, which have anti-inflammatory, pain-relieving, anti-tumor, anti-oxidation, immunomodulatory and other pharmacological effects. Therefore, this medicinal material is widely used in clinical practice. By reviewing the relevant literature, this study systematically introduced the research status about the chemical constituents and pharmacological effects of processed Angelicae Sinensis Radix products, aiming to provide a theoretical reference and support for the future research, development, and clinical application of related drugs.


Assuntos
Angelica sinensis , Medicamentos de Ervas Chinesas , Óleos Voláteis , Medicamentos de Ervas Chinesas/farmacologia , Anti-Inflamatórios , Dor
12.
Angew Chem Int Ed Engl ; 62(44): e202308921, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37668952

RESUMO

Covalent organic frameworks (COFs), as a burgeoning class of crystalline porous materials, have made significant progress in their application to optoelectronic devices such as field-effect transistors, memristors, and photodetectors. However, the insoluble features of microcrystalline two-dimensional (2D) COF powders limit development of their thin film devices. Additionally, the exploration of spin transport properties in this category of π-conjugated skeleton materials remains vacant thus far. Herein, an imine-linked 2D Py-Np COF nanocrystalline powder was synthesized by Schiff base condensation of 4,4',4'',4'''-(pyrene-1,3,6,8-tetrayl)tetraaniline and naphthalene-2,6-dicarbaldehyde. Then, we prepared a large-scale free-standing Py-Np COF film via a top-down strategy of chemically assisted acid exfoliation. Moreover, high-quality COF films acted as active layers were transferred onto ferromagnetic La0.67 Sr0.33 MnO3 (LSMO) electrodes for the first attempt to fabricate organic spin valves (OSVs) based on 2D COF materials. This COF-based OSV device with a configuration of LSMO/Py-Np COF/Co/Au demonstrated a remarkable magnetoresistance (MR) value up to -26.5 % at 30 K. Meanwhile, the MR behavior of the COF-based OSVs exhibited a highly temperature dependence and operational stability. This work highlights the enormous application prospects of 2D COFs in organic spintronics and provides a promising approach for developing electronic and spintronic devices based on acid-exfoliated COF thin films.

13.
Neuroendocrinology ; 112(10): 966-981, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34847556

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common reproductive and metabolic disorder characterized by high androgen levels. The aim of this study was to evaluate the effects of hyperandrogenism on the hypothalamus and subsequently on the food intake and obesity in females. METHODS: A dihydroxy testosterone (DHT)-induced rat model was established to recapitulate the hyperandrogenism features of PCOS patients. Body weight and food intake of the rats were recorded. The food intake of DHT-induced rats was restricted by pair feeding to exclude possible effects of weight gain on the hypothalamus. The expression levels of relevant proteins and mRNAs in the hypothalamus and primary hypothalamic neurons exposed to DHT were analyzed by Western blotting and RT-PCR, respectively. The leptin levels in the serum and cerebrospinal fluid (CSF) were measured, and leptin was injected via the intracerebroventricular (ICV) route to test the leptin sensitivity of the hypothalamus. RESULTS: The excessive prepuberty androgen levels in the DHT-induced rats markedly elevated food intake prior to weight gain. Consistent with this, the expression of neuropeptide Y and agouti-related peptide mRNAs was upregulated, which occurred prior to obesity and even with restricted food intake. In addition, the hypothalamic sensitivity to insulin and leptin was also impaired in the DHT-induced rats before obesity and with restricted food intake. DHT significantly reduced the leptin levels in the CSF, and ICV injection of leptin inhibited the DHT-induced increase in food intake. CONCLUSIONS: Androgen excess increased food intake in rats and promoted obesity by downregulating insulin and leptin signaling in the hypothalamus, most likely by suppressing leptin levels in the CSF.


Assuntos
Hiperandrogenismo , Síndrome do Ovário Policístico , Androgênios/metabolismo , Animais , Peso Corporal , Ingestão de Alimentos , Feminino , Humanos , Hipotálamo/metabolismo , Insulina/metabolismo , Leptina/metabolismo , Neuropeptídeo Y/metabolismo , Obesidade/induzido quimicamente , Obesidade/metabolismo , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/metabolismo , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais , Testosterona/metabolismo , Aumento de Peso
14.
J Am Soc Nephrol ; 32(3): 545-552, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33593824

RESUMO

BACKGROUND: Galactose-deficient IgA1 plays a key role in the pathogenesis of IgA nephropathy, the most common primary GN worldwide. Although serum levels of galactose-deficient IgA1 have a strong genetic component, the genetic link between this molecule and IgA nephropathy has not yet been clearly established. METHODS: To identify novel loci associated with galactose-deficient IgA1, we performed a quantitative genome-wide association study for serum galactose-deficient IgA1 levels, on the basis of two different genome-wide association study panels conducted in 1127 patients with IgA nephropathy. To test genetic associations with susceptibility to IgA nephropathy, we also enrolled 2352 patients with biopsy-diagnosed IgA nephropathy and 2632 healthy controls. Peripheral blood samples from 59 patients and 27 healthy controls were also collected for gene expression analysis. RESULTS: We discovered two loci, in C1GALT1 and GALNT12, that achieved genome-wide significance, explaining about 3.7% and 3.4% of variance in serum galactose-deficient IgA1 levels, respectively. We confirmed the previously reported association of C1GALT1 with serum galactose-deficient IgA1 levels, but with a different lead single-nucleotide polymorphism (rs10238682; ß=0.26, P=1.20×10-9); the locus we identified at GALNT12 (rs7856182; ß=0.73, P=2.38×10-9) was novel. Of more interest, we found that GALNT12 exhibits genetic interactions with C1GALT1 in both galactose-deficient IgA1 levels (P=1.40×10-2) and disease risk (P=6.55×10-3). GALNT12 mRNA expression in patients with IgA nephropathy was significantly lower compared with healthy controls. CONCLUSIONS: Our data identify GALNT12 as a novel gene associated with galactose-deficient IgA1 and suggest novel genetic interactions. These findings support a key role of genetically conferred dysregulation of galactose-deficient IgA1 in the development of IgA nephropathy.


Assuntos
Galactosiltransferases/genética , Glomerulonefrite por IGA/genética , Glomerulonefrite por IGA/imunologia , Imunoglobulina A/sangue , N-Acetilgalactosaminiltransferases/genética , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Epistasia Genética , Feminino , Galactose/química , Frequência do Gene , Estudo de Associação Genômica Ampla , Glomerulonefrite por IGA/enzimologia , Glicosilação , Humanos , Imunoglobulina A/química , Masculino , Herança Multifatorial , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , RNA Mensageiro/sangue , RNA Mensageiro/genética , Fatores de Risco
15.
Sensors (Basel) ; 23(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36616651

RESUMO

Automatic crack detection is always a challenging task due to the inherent complex backgrounds, uneven illumination, irregular patterns, and various types of noise interference. In this paper, we proposed a U-shaped encoder-decoder semantic segmentation network combining Unet and Resnet for pixel-level pavement crack image segmentation, which is called RUC-Net. We introduced the spatial-channel squeeze and excitation (scSE) attention module to improve the detection effect and used the focal loss function to deal with the class imbalance problem in the pavement crack segmentation task. We evaluated our methods using three public datasets, CFD, Crack500, and DeepCrack, and all achieved superior results to those of FCN, Unet, and SegNet. In addition, taking the CFD dataset as an example, we performed ablation studies and compared the differences of various scSE modules and their combinations in improving the performance of crack detection.


Assuntos
Iluminação , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador
16.
J Mol Cell Cardiol ; 159: 80-90, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34097926

RESUMO

Circular RNAs (circRNAs) are essential regulators associated with many cardiac conditions, including myocardial infarction (MI). This study aimed to explore circRNA expression during MI development in an animal model and in hypoxia/reoxygenation (H/R)-treated cardiomyocytes. Microarray and real-time quantitative PCR showed that the circRNA PVT1 (circPVT1) was expressed at high levels in MI tissues and H/R-triggered cardiomyocytes. Loss-of-function assays were utilized for examining the influence of circPVT1 on cardiac function and cardiomyocyte properties. Cardiac function was measured by echocardiography at 7 d after MI. Reduced circPVT1 expression significantly decreased MI-triggered myocardial infarct size by 60% and prevented MI-triggered reductions in fractional shortening (%FS) and ejection fraction (EF%). Results of LDH, CCK-8, EdU staining, colony formation assays, and flow cytometry showed that circPVT1 silencing restored cell viability and proliferation while decreased apoptosis. Mechanistic experiments indicated that microRNAs (miR)-125b and miR-200a associated with circPVT1. We demonstrated that circPVT1 functioned as a competitive endogenous RNA (ceRNA) to sponge both miR-125b and miR-200a. Gain-of-function assays showed that miR-125b and miR-200a upregulation partially eliminated the effects of circPVT1 on cardiomyocyte properties. In addition, we found that the previously reported p53/TRAF6, SIRT7, Keap1/Nrf2, and PDCD4 pathways were regulated by the circPVT1/miR-125b/miR-200a axis. In conclusion, our study suggests that circPVT1 protects the myocardium from MI and H/R injury by preventing miR-125b- and miR-200a-mediated apoptotic signaling.


Assuntos
MicroRNAs/genética , Interferência de RNA/fisiologia , RNA Circular/genética , RNA Longo não Codificante/genética , Traumatismo por Reperfusão/genética , Animais , Apoptose/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Transdução de Sinais/genética , Regulação para Cima/genética
17.
Small ; 17(47): e2100918, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34288393

RESUMO

Covalent-organic frameworks (COFs) are especially interesting and unique as their highly ordered topological structures entirely built from plentiful π-conjugated units through covalent bonds. Arranging tailorable organic building blocks into periodically reticular skeleton bestows predictable lattices and various properties upon COFs in respect of topology diagrams, pore size, properties of channel wall interfaces, etc. Indeed, these peculiar features in terms of crystallinity, conjugation degree, and topology diagrams fundamentally decide the applications of COFs including heterogeneous catalysis, energy conversion, proton conduction, light emission, and optoelectronic devices. Additionally, this research field has attracted widespread attention and is of importance with a major breakthrough in recent year. However, this research field is running with the lack of summaries about tailorable construction of 2D COFs for targeted functionalities. This review first covers some crucial polymeric strategies of preparing COFs, containing boron ester condensation, amine-aldehyde condensation, Knoevenagel condensation, trimerization reaction, Suzuki CC coupling reaction, and hybrid polycondensation. Subsequently, a summary is made of some representative building blocks, and then underlines how the electronic and molecular structures of building blocks can strongly influence the functional performance of COFs. Finally, conclusion and perspectives on 2D COFs for further study are proposed.

18.
Nanotechnology ; 32(29)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33711826

RESUMO

Doxorubicin (DOX) is a commonly used anticancer drug, but it is inefficient as a therapeutic due to a lack of targeting. Peptide-tuned self-assembly of DOX offers a strategy to improve targeting for greater efficacy. In this work, we designed and prepared an amphiphilic tumor cell-targeting peptide, P14 (AAAAFFFHHHGRGD), able to encapsulate DOX by self-assembly to form tumor cell-targeting and pH-sensitive nano-micelles. The results showed a critical P14-micelle concentration of 1.758 mg l-1and an average particle size of micelles of 121.64 nm, with entrapment and drug-loading efficiencies of 28.02% ± 1.35% and 12.06% ± 0.59%, respectively. The prepared micelles can release 73.52 ± 1.27% DOX within 24 h in pH 4.5 medium, and the drug cumulative release profile of micelles can be described by the first-order model. Compared with free DOX, the micelles exhibited an increased ability to inhibit tumor cell growth and cause tumor apoptosisin vitro, with IC50values of DOX and P14-DOX micelles against human breast cancer cells (MCF-7) of 0.91 ± 0.07 and 0.75 ± 0.06µg ml-1, respectively, and cellular apoptotic rates of DOX and P14-DOX micelles of 70.3% and 42.4%, respectively. Cellular uptake experiments revealed high concentrations of micelles around and inside MCF-7 cells, demonstrating that micelles can target tumor cells. These results indicate the excellent potential for the application of this amphiphilic peptide as a carrier for small-molecule drugs and suggest a strategy for the design of effective anti-tumor drugs.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos , Nanoestruturas/química , Peptídeos/metabolismo , Antibióticos Antineoplásicos/química , Apoptose/efeitos dos fármacos , Doxorrubicina/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Cinética , Células MCF-7 , Micelas , Terapia de Alvo Molecular , Nanoestruturas/ultraestrutura , Peptídeos/síntese química
19.
Proc Natl Acad Sci U S A ; 115(48): E11388-E11396, 2018 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30413620

RESUMO

Located within the brain's ventricles, the choroid plexus produces cerebrospinal fluid and forms an important barrier between the central nervous system and the blood. For unknown reasons, the choroid plexus produces high levels of the protein klotho. Here, we show that these levels naturally decline with aging. Depleting klotho selectively from the choroid plexus via targeted viral vector-induced knockout in Klothoflox/flox mice increased the expression of multiple proinflammatory factors and triggered macrophage infiltration of this structure in young mice, simulating changes in unmanipulated old mice. Wild-type mice infected with the same Cre recombinase-expressing virus did not show such alterations. Experimental depletion of klotho from the choroid plexus enhanced microglial activation in the hippocampus after peripheral injection of mice with lipopolysaccharide. In primary cultures, klotho suppressed thioredoxin-interacting protein-dependent activation of the NLRP3 inflammasome in macrophages by enhancing fibroblast growth factor 23 signaling. We conclude that klotho functions as a gatekeeper at the interface between the brain and immune system in the choroid plexus. Klotho depletion in aging or disease may weaken this barrier and promote immune-mediated neuropathogenesis.


Assuntos
Envelhecimento/imunologia , Encéfalo/imunologia , Plexo Corióideo/imunologia , Glucuronidase/imunologia , Envelhecimento/genética , Animais , Feminino , Glucuronidase/genética , Hipocampo/imunologia , Humanos , Proteínas Klotho , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia
20.
J Asian Nat Prod Res ; 23(3): 271-283, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32175779

RESUMO

Sixteen substituted 1-hydroxy-3-methylxanthones were synthesized in one step. The yields ranged from 33 to 76%. Then, the antitumor, antioxidant, anti-tyrosinase, anti-pancreatic lipase, and antifungal activities of compounds 1-16 were evaluated. Compounds 10-12 and 14 inhibited tyrosinase and pancreatic lipase activity to a certain extent, respectively. Compound 16 exhibited obvious cytotoxicity against fifteen cancer cells, moderate antioxidant activity, and moderate inhibitory activity against Candida albicans. In particular, compound 16 exhibited strong inhibitory activity against A-549 and A549/Taxol cells. These results demonstrated that compounds 10-12, 14, and 16 are promising leads for further structural modification.[Formula: see text].


Assuntos
Xantonas , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Estrutura Molecular , Monofenol Mono-Oxigenase , Relação Estrutura-Atividade , Xantonas/farmacologia
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