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1.
J Am Chem Soc ; 146(1): 101-105, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38150536

RESUMO

Metal organic frameworks (MOFs), a class of porous crystalline materials consisting of metal-based nodes and organic linkers, have emerged as a promising platform for photocatalysis due to their ultrahigh functional surface area, customizable topologies, and tunable energetics. While interesting photochemistry has been reported, the related photoinduced structural dynamics of MOFs remains unclear. The consensus is that the coordination bonds between MOF nodes and linkers are considered static during photoexcitation, while the open-metal sites on the nodes are taken as the key active sites for catalysis. In this work, through a complementary time-resolved visible and infrared (IR) spectroscopic investigation, along with computational studies, we report for the first time light-induced structural bond dissociation (COO-M) and reformation in an iron-oxo framework, MIL-101(Fe). The probed excited state displayed ligand-to-metal charge transfer (LMCT) characteristics and exhibited a ca. 30 µs lifetime. The incredibly long excited-state lifetime led us to probe potential structural rearrangements that facilitated charge separation in MIL-101(Fe). By probing the vibrational fingerprints of the carboxylate linker upon LMCT photoexcitation, we observed the reversible transition of the carboxylate-Fe bond from a bidentate bridging mode to a monodentate mode, indicating the partial dissociation of the carboxylate ligand. Importantly, the bidentate configuration is recovered on the same time scale of the excited state lifetimes as probed via visible transient absorption spectroscopy. The elucidated photoinduced configurational dynamics provides a foundation for an in-depth understanding of MOF-based photocatalytic mechanisms.

2.
J Am Chem Soc ; 146(7): 4309-4313, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38330249

RESUMO

To date, spectroscopic characterization of porphyrin-based metal organic frameworks (MOFs) has relied almost exclusively on ensemble techniques, which provide only structurally averaged insight into the functional properties of these promising photochemical platforms. This work employs time-resolved pump-probe microscopy to probe ultrafast dynamics in PCN-222 MOF single crystals. The simultaneous high spatial and temporal resolution of the technique enables the correlation of spectroscopic observables to both inter- and intracrystal structural heterogeneity. The pump-probe measurements show that significant differences in the excited state lifetime exist between individual PCN-222 crystals of an ensemble. On a single PCN-222 crystal, differences in excited state lifetime and photoluminescence quantum yield are found to correlate to microscale structural defects introduced at crystallization. Pump probe microscopy also enables the direct measurement of excited state transport. Imaging of exciton transport on individual MOF crystals reveals rapid, but subdiffusive exciton transport which slows on the 10s of ps time scale. Time-averaged exciton diffusion coefficients over the first 200 ps span a range of 0.27 to 1.0 cm2/s, indicating that excited states are rapidly transported through the porphyrin network of PCN-222 before being trapped. Together, these single-particle-resolved measurements provide important new insight into the role played by structural defects on the photochemical functionality of porphyrin-based MOFs.

3.
J Clin Biochem Nutr ; 73(2): 154-160, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37700851

RESUMO

MicroRNA (miR)-499a-5p has been reported to regulate the progression of various tumours. However, the role of miR-499a-5p in breast cancer is unclear. The purpose of this study was to investigate the role and mechanism of miR-499a-5p in breast cancer. The growth effect of miR-499a-5p on breast cancer cells was investigated by the CCK-8 assay, wound healing assay and Transwell invasion assay. The luciferase activity assay was used to verify the downstream targets of miR-499a-5p. The levels of GSH, MDA, and ROS were detected by kits. Quantitative real-time PCR and Western blot were used to determine the expression levels of TMEM189, COX-2, GPX4, and other related genes in cells. miR-499a-5p was down-regulated in MDA-MB-231 cells and was shown to reduced the viability, migration and invasion of MDA-MB-231 cells. Further studies revealed that TMEM189 is a target of miR-499a-5p. miR-499a-5p inhibited breast cancer cell growth by downregulating TMEM189. Furthermore, the down-regulation of TMEM189 promotes ferroptosis in breast cancer cells. The low expression of TMEM189 inhibited the development of breast cancer through the ferroptosis pathway. We have demonstrated for the first time that miR-499a-5p inhibits breast cancer progression by targeting the TMEM189-mediated ferroptosis pathway.

4.
Int J Syst Evol Microbiol ; 72(10)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36223175

RESUMO

A Gram-stain-negative, aerobic, rod-shaped bacterium (D1M17T) was isolated from the seawater surrounding scleractinian coral Acropora digitifera in Daya Bay, Shenzhen, PR China. Strain D1M17T grew with 0-10 % (w/v) NaCl (optimum, 3-4 %), at 15-37 °C (optimum, 28 °C) and at pH 4.5-8.5 (optimum, pH 7.0-7.5). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain D1M17T formed a lineage within the genus Aquimarina, family Flavobacteriaceae, and it was distinct from the most closely related species Aquimarina salinaria LMG 25375T, Aquimarina gracilis JCM 17453T and Aquimarina spongiae KCTC 22663T with 16S rRNA gene sequence similarities of 97.2, 97.2 and 97.1 %, respectively. The major respiratory quinone was MK-6. The predominant fatty acids (more than 10 %) were iso-C15 : 0 (28.8 %), iso-C17 : 0 3-OH (21.5 %) and iso-C15 : 1 G (13.1 %). The DNA G+C content of D1M17T was 34.4 mol%. The polar lipids in D1M17T comprised one phospholipid and five unknown polar lipids. Phenotypic characteristics (physiological, biochemical and chemotaxonomic) also supported the taxonomic novelty of this isolate. Thus, strain D1M17T is considered to represent a novel species within the genus Aquimarina, for which the name Aquimarina acroporae sp. nov. is proposed. The type strain is D1M17T (=KCTC 92172T= MCCC 1K07224T).


Assuntos
Antozoários , Flavobacteriaceae , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA , Cloreto de Sódio , Vitamina K 2/química
5.
Inorg Chem ; 61(22): 8585-8591, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35613459

RESUMO

Metal-organic frameworks (MOFs) have shown great success in aqueous-phase hydrolysis of nerve agents, with some even showing promise in the gas phase. However, both aqueous-phase reactivity and gas-phase reactivity are hindered because of the binding of the hydrolyzed products to the MOF nodes in a stable, bridging configuration, which limits turnover. Single transition-metal atoms in MOFs have been a growing field of interest for catalytic applications, and single atoms have been proposed to prevent the unwanted bridged conformation and increase catalytic turnover. To date, there has been little experimental evidence to support the hypothesis. Herein, we report two copper single atom-modified UiO-66 MOFs for nerve-agent simulant degradation. Despite the capping of highly active Zr4+ nodes with fewer Lewis acidic Cun+ atoms, the reactivity of both CuMOFs approaches that of native UiO-66 under aqueous conditions. Computational studies reveal that the Cu coordination environment impairs product inhibition with respect to the native MOF.


Assuntos
Estruturas Metalorgânicas , Agentes Neurotóxicos , Compostos Organometálicos , Cobre , Estruturas Metalorgânicas/química , Agentes Neurotóxicos/química , Ácidos Ftálicos
6.
BMC Med Imaging ; 22(1): 27, 2022 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-35151256

RESUMO

BACKGROUND: Microwave ablation (MWA) is a popular therapy for liver malignant tumor in recent years. Few studies have been conducted on its use in the treatment of hepatic alveolar echinococcosis (HAE). The study aims to evaluate the efficacy and safety of MWA in the treatment of HAE. METHODS: This study analyzed the data of 45 patients (mean age, 38 ± 2 years; 24 males) diagnosed with HAE and underwent MWA treatment between June 2014 to December 2019. The patients after MWA were examined by CT or MRI [follow-up: 32 months (IQR 23-48.5)] to determine whether the lesions were relapsed and to evaluate the therapeutic effect of MWA. The safety of MWA was evaluated by monitoring postoperative complications. Clinical data, such as patient demographics, imaging features of the lesions, relevant findings of laboratory tests before and after ablation, and information related to ablation, were collected and analyzed. Paired-sample t tests and paired-sample Wilcoxon signed-rank tests were used to compare relevant laboratory indicators before and after MWA. RESULTS: MWA was applied to 57 HAE lesions in 45 patients. The median size of lesions was 3.42 cm (IQR2.85-4.41). The rate of complete ablation was 100% (57/57). The median follow-up time was 32 months (IQR 23-48.5). The recurrence rate was 13% (6/45), and the median time of recurrence was 22 months. The rate of minor complications was 11.1% (5/45), and there were no major complications and deaths. Compared to preoperative, ALB, RBC, HBG, and PLT were decreased (p < 0.001); ALT, TB, DB, and WBC were increased (p < 0.001); and no statistically difference in PT, APTT, and INR (p > 0.05). CONCLUSIONS: MWA might be a safe and effective way to cure HAE. Meanwhile, it provides a new option and a new way of thinking about treatment for patients with HAE.


Assuntos
Ablação por Cateter/métodos , Equinococose Hepática/cirurgia , Ultrassonografia de Intervenção , Adulto , Ablação por Cateter/efeitos adversos , Equinococose Hepática/diagnóstico por imagem , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/cirurgia , Masculino , Micro-Ondas
7.
Int J Mol Sci ; 23(6)2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35328495

RESUMO

CONSTANS (CO) is an important regulator of photoperiodic flowering and functions at a key position in the flowering regulatory network. Here, two CO homologs, MiCOL16A and MiCOL16B, were isolated from "SiJiMi" mango to elucidate the mechanisms controlling mango flowering. The MiCOL16A and MiCOL16B genes were highly expressed in the leaves and expressed at low levels in the buds and flowers. The expression levels of MiCOL16A and MiCOL16B increased during the flowering induction period but decreased during the flower organ development and flowering periods. The MiCOL16A gene was expressed in accordance with the circadian rhythm, and MiCOL16B expression was affected by diurnal variation, albeit not regularly. Both the MiCOL16A and MiCOL16B proteins were localized in the nucleus of cells and exerted transcriptional activity through their MR domains in yeast. Overexpression of both the MiCOL16A and MiCOL16B genes significantly repressed flowering in Arabidopsis under short-day (SD) and long-day (LD) conditions because they repressed the expression of AtFT and AtSOC1. This research also revealed that overexpression of MiCOL16A and MiCOL16B improved the salt and drought tolerance of Arabidopsis, conferring longer roots and higher survival rates to overexpression lines under drought and salt stress. Together, our results demonstrated that MiCOL16A and MiCOL16B not only regulate flowering but also play a role in the abiotic stress response in mango.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Mangifera , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Ritmo Circadiano , Flores , Regulação da Expressão Gênica de Plantas , Mangifera/genética , Mangifera/metabolismo , Fotoperíodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
8.
Inorg Chem ; 60(21): 16378-16387, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34672622

RESUMO

Defect engineering in metal-organic frameworks (MOFs) has recently become an area of significant research due to the possibility of enhancing material properties such as internal surface area and catalytic activity while maintaining stable 3D structures. Through a modulator screening study, the model Zr4+ MOF, UiO-66, has been synthesized with control of particle sizes (100-1900 nm) and defect levels (2-24%). By relating these properties, two series were identified where one property remained constant, allowing for independent analysis of the defect level or particle size, which frequently change coincident with the modulator choice. The series were used to compare UiO-66 reactivity for the hydrolysis of a chemical warfare agent simulant, dimethyl 4-nitrophenylphosphate (DMNP). The rate of DMNP hydrolysis displayed high dependence on the external surface area, supporting a reaction dominated by surface interactions. Moderate to high concentrations of defects (14-24%) allow for the accessibility of some interior MOF nodes but do not substantially promote diffusion into the framework. Individual control of defect levels and particle sizes through modulator selection may provide useful materials for small molecular catalysis and provide a roadmap for similar engineering of other zirconium frameworks.

9.
Inorg Chem ; 60(14): 10439-10450, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34190552

RESUMO

The porphyrinic metal-organic framework, PCN-222, exhibits anisotropic growth behavior to form nanorods and microrods with aspect ratios 3 < x < 94. Control of microrod aspect ratios has been demonstrated through the identification of several factors that dictate crystal growth, particularly the concentrations of a ligand, a modulator, and an exogenous base. An increase in the local concentration of a deprotonated ligand, which is proportional to the nucleation rate, is associated with smaller crystals, while increased modulator concentration leads to longer microrods. Addition of a deprotonating agent not only contributes to higher aspect ratios but also results in an improvement to particle dispersity. Here, we report acid-base co-modulation methods with difluoroacetic acid and triethylamine to effectively tune PCN-222 aspect ratios. A series of mechanisms is identified for the growth of PCN-222: (1) ligand deprotonation, (2) nucleation, (3) oriented attachment, (4) Ostwald ripening, and (5) dissolution-recrystallization. Time trials of co-modulated samples revealed three separate ripening growth events, with each resulting in larger and more monodisperse crystals. With an understanding of these crystal growth factors and mechanisms, the highest aspect ratio, non-templated metal-organic frameworks were synthesized (94 ± 9).

10.
J Am Chem Soc ; 142(20): 9158-9162, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32392041

RESUMO

The plasmonic properties of silver nanoparticle (AgNP) arrays are directly controlled by AgNP size, shape, and spatial arrangement. Reported here is a strategy to prepare chiral AgNP arrays templated by two constitutionally isomeric aromatic peptide amphiphiles (APAs), KSC'EKS and C'EKSKS (KS = S-aroylthiooxime-modified lysine, C' = citrulline, and E = glutamic acid). In phosphate buffer, both APAs initially self-assembled into nanoribbons with a similar geometry. However, in the presence of silver ions and poly(sodium 4-styrenesulfonate) (PSSS), one of the nanoribbons (KSC'EKS) turned into nanohelices with a regular twisting pitch, while the other (C'EKSKS) remained as nanoribbons. Both were used as templates for synthesis of arrays of ∼8 nm AgNPs to understand how small changes in molecular structure affect the plasmonic properties of these chiral AgNP/APA hybrids. Both hybrids showed improved colloidal stability compared to pure AgNPs, and both showed enhanced sensitivity as surface-enhanced Raman spectroscopy (SERS) substrates for model analytes, with nanohelices showing better SERS performance compared to their nanoribbon counterparts and pure AgNPs.


Assuntos
Nanopartículas Metálicas/química , Peptídeos/síntese química , Prata/química , Estrutura Molecular , Tamanho da Partícula , Peptídeos/química , Propriedades de Superfície
11.
J Am Chem Soc ; 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33215496

RESUMO

Metal-organic frameworks (MOFs) are emerging as a promising platform for solar energy conversion applications. Their potential utilization as efficient chromophores in artificial photosynthesis is closely related to the understanding of light-harvesting and energy transfer processes that occur within these molecular scaffolds. Herein, we present the photophysical investigation of Ru(II), Ir(III), and Os(II) polypyridyl complexes incorporated into the backbone of UiO-67. In this work, we systematically study the effect of spin-orbit coupling on dipole-dipole energy transfer in MOFs using steady-state and time-resolved spectroscopic techniques. The results of our work indicate successful triplet-to-singlet energy transfer and a sizable increase in the transfer kinetics and critical distance, as direct consequences of strong spin-orbit couplings. Remarkably, the reported R0 value for OsDCBPY (R0 = 88 ± 10 Å) represents one of the largest Förster distances observed in an MOF. Collectively, this work contributes to the general knowledge of energy transfer in materials and provides groundwork for efficient utilization in artificial photosynthetic assemblies.

12.
Biomacromolecules ; 20(12): 4593-4601, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31696706

RESUMO

Eumelanin is a ubiquitous natural pigment that has a broad absorption across ultraviolet (UV, 100-400 nm) and visible wavelengths (400-700 nm) and can protect against radiation. Synthetic eumelanin with properties similar to natural eumelanin has been made using dopamine or dihydroxyindole. Here, we use solid-state nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy to elucidate the chemical structure of synthetic eumelanins (made from dopamine and l-3,4-dihydroxyphenylalanine precursors) and investigate how their structures change after intensive UVA (315-400 nm) exposure. We first confirm that polydopamine has indole units. Upon UV exposure, the pyrrole ring in this indole unit remains intact, and a fraction of the six-membered benzyl ring is broken and the indole potentially converted to furo[3,4-b]pyrrole. This change in the chemical structure is accompanied by a release of carbon dioxide. In addition, the sepia (natural) eumelanin used for comparison is more stable than the synthetic eumelanin. Understanding the UVA degradation mechanism of eumelanin will help reveal the role of eumelanin in skin cancer and in the design of more efficient UV stabilizers.


Assuntos
Melaninas/química , Processos Fotoquímicos , Raios Ultravioleta , Animais , Humanos , Melaninas/metabolismo , Neoplasias Cutâneas/metabolismo
13.
Chem Sci ; 14(18): 4672-4680, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37181771

RESUMO

Artificial photosynthesis is one of the most promising forms of renewable fuel production, due to the abundance of water, carbon dioxide, and sunlight. However, the water oxidation reaction remains a significant bottleneck due to the high thermodynamic and kinetic requirements of the four-electron process. While significant work has been done on the development of catalysts for water splitting, many of the catalysts reported to date operate at high overpotentials or with the use of sacrificial oxidants to drive the reaction. Here, we present a catalyst embedded metal-organic framework (MOF)/semiconductor composite that performs photoelectrochemical oxidation of water at a formal underpotential. Ru-UiO-67 (where Ru stands for the water oxidation catalyst [Ru(tpy)(dcbpy)OH2]2+ (tpy = 2,2':6',2''-terpyridine, dcbpy = 5,5-dicarboxy-2,2'-bipyridine)) has been previously shown to be active for water oxidation under both chemical and electrochemical conditions, but here we demonstrate, for the first time, incorporation of a light harvesting n-type semiconductor as a base photoelectrode. Ru-UiO-67/WO3 is active for photoelectrochemical water oxidation at a thermodynamic underpotential (η ≈ 200 mV; Eonset = 600 mV vs. NHE), and incorporation of a molecular catalyst onto the oxide layer increases efficiency of charge transport and separation over bare WO3. The charge-separation process was evaluated with ultrafast transient absorption spectroscopy (ufTA) and photocurrent density measurements. These studies suggest that a key contributor to the photocatalytic process involves a hole transfer from excited to Ru-UiO-67. To our knowledge, this is the first report of a MOF-based catalyst active for water oxidation at a thermodynamic underpotential, a key step towards light-driven water oxidation.

14.
Sci Total Environ ; 892: 164258, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37209734

RESUMO

Coral bleaching and coral reef degradation have been severely increased due to anthropogenic impacts, especially global warming. Studies have indicated the key role of host-microbiome symbiotic relationships for the coral holobiont health and development, although not all of the mechanisms of interaction have been fully explored. Here, we explore bacterial and metabolic shifts within coral holobionts under thermal stress, and its correlation with bleaching. Our results showed obvious signs of coral bleaching after 13 days of heating treatment, and a more-complex co-occurrence network was observed in the coral-associated bacterial community of the heating group. The bacterial community and metabolites changed significantly under thermal stress, and genera Flavobacterium, Shewanella and Psychrobacter increased from <0.1 % to 43.58 %, 6.95 % and 6.35 %, respectively. Bacteria potentially associated with stress tolerance, biofilm formation and mobile elements decreased from 80.93 %, 62.15 % and 49.27 % to 56.28 %, 28.41 % and 18.76 %, respectively. The differentially expressed metabolites of corals after heating treatment, such as Cer(d18:0/17:0), 1-Methyladenosine, Trp-P-1 and Marasmal, were associated with cell cycle regulation and antioxidant properties. Our results can contribute to our current understanding on the correlations between coral-symbiotic bacteria, metabolites and the coral physiological response to thermal stress. These new insights into the metabolomics of heat-stressed coral holobionts may expand our knowledge on the mechanisms underlying bleaching.


Assuntos
Antozoários , Microbiota , Animais , Branqueamento de Corais , Recifes de Corais , Antozoários/fisiologia , Resposta ao Choque Térmico , Bactérias , Simbiose
15.
Oncol Lett ; 25(1): 31, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36589663

RESUMO

Numerous studies have shown that the release of stress hormones resulting from repeated exposure to chronic psychological stress increases DNA damage and promotes tumorigenesis. However, the mechanisms that enable cancerous cells adapt to stress hormone-induced DNA damage and survive remain unclear. The present study aimed to investigate the impact of stress hormones on the survival of liver cancer cells and the underlying mechanism. HepG2 human liver cancer cells were treated with dexamethasone (DEX), epinephrine (EPI) and norepinephrine (NE) and subjected to the testing of DNA damage, cell survival and cell apoptosis by alkaline comet assay, CCK-8 viability assay and flow cytometry, respectively. The protein expression levels of DNA damage response factors were determined by western blotting analysis. The results revealed that treatment of HepG2 cells with DEX, EPI and NE induced DNA damage without affecting cell survival or inducing apoptosis. The protein levels of wild-type p53-induced phosphatase 1 (Wip1), a type 2C family serine/threonine phosphatase, were increased, and the dephosphorylation of DNA damage response factors, including phosphorylated (p-)ataxia-telangiectasia mutated and p-checkpoint kinase 2, occurred following treatment with DEX, EPI and NE. In addition, a cycloheximide chase assay was performed to explore the protein stability under treatment with stress hormones. Compared with vehicle-treated cells, Wip1 exhibited increased protein stability in stress hormone-treated HepG2 cells. Eventually, the depletion of Wip1 using small interfering RNA verified the role of Wip1 in the modulation of stress hormone-induced DNA damage. These findings suggest that cancerous cells likely adapt to stress hormone-induced DNA damage via Wip1 upregulation. The present study provides an insight into the underlying mechanism that links chronic psychological stress with tumor growth and progression.

16.
Front Med (Lausanne) ; 9: 879982, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572999

RESUMO

Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease with the high case-fatality rate, lacking effective therapies and vaccines. Inflammation-based indexes have been widely used to predict the prognosis of patients with cancers and some inflammatory diseases. In our study, we aim to explore the predictive value of the inflammation-based indexes in SFTS patients. Methods: We retrospectively analyzed 82 patients diagnosed with SFTS. The inflammation-based indexes, including neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), aggregate index of systemic inflammation (AISI) and C-reactive protein to albumin ratio (CAR), were compared between the survival and death patients. Receiver operating characteristic (ROC) curves were used to compare the predictive ability of MLR, AISI, and CAR. The survival analysis was based on the Kaplan-Meier (KM) method. Multivariate logistic regression analysis was used to analyze the independent risk factors of poor prognosis in patients with SFTS. Results: The CAR is higher in the death group while MLR and AISI were higher in the survival group. The ROC curve analysis indicated CAR exhibited more predictive value than the other indexes and the optimal cut-off value of CAR was equal to or greater than 0.14. KM survival curve showed that higher CAR was significantly correlated to the lower overall survival in SFTS patients. Multivariate logistic regression analysis indicated that CAR was an independent risk factor for poor prognosis in patients with SFTS. Conclusion: The CAR is an independent risk factor for death in patients with SFTS and could predict the poor prognosis of SFTS patients. It could be used as a biomarker to help physicians to monitor and treat patients more aggressively to improve clinical prognosis.

17.
Front Cell Dev Biol ; 10: 824938, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693941

RESUMO

Background: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world with high morbidity and mortality. Identifying specific molecular markers that can predict HCC prognosis is extremely important. MELK has been reported to play key roles in several types of human cancers and predict poor prognosis. This study was aimed to explore the impact of MELK on HCC. Methods: A pan-cancer analysis of MELK was conducted by The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) data. The prognosis of MELK in various cancers was analyzed in GEPIA. Then, a ceRNA network of MELK was constructed based on the comprehensive consideration of the expression analysis, the correlation analysis, and the survival analysis by R software. The correlation of MELK and immune cell infiltration was analyzed by TIMER and CIBERSORT. Then, the overall survival of differentially expressed immune cells was conducted. The correlation of MELK and immune checkpoints expression was analyzed by GEPIA. Results: MELK was overexpressed in 14 types of human cancers, and its expression was significantly higher than that in both unmatched and paired normal samples in HCC. Higher MELK expression was correlated with poorer survival and advanced clinical stage, topography (T) stage, and histological grade. The univariate and multivariate Cox regression analyses showed that MELK was an independent risk factor for poor prognosis in HCC. Then, we constructed a ceRNA network consisting of MELK, miR-101-3p, and two lncRNAs (SNHG1 and SNHG6) after evaluating the expression and impact on prognosis in HCC of these RNAs. TIMER and CIBERSORT databases indicated that MELK was correlated with various immune cells including B cells, CD8+ T cells, CD4+ T cells, macrophage, neutrophil, and dendritic cells in HCC. Of them, B cells, CD4+ T cells, macrophage, and neutrophil were related to the prognosis of HCC. In addition, MELK was significantly positively correlated with the immune checkpoint genes. Conclusions: MELK may be a novel potential biomarker for predicting prognosis and immunotherapy efficacy in patients with HCC. Our study may provide new molecular and therapeutic strategies for the treatment of HCC patients.

18.
J Gastrointest Surg ; 26(9): 1982-1997, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35680777

RESUMO

OBJECTIVES: To systematically evaluate the clinical efficacy of rectal nonsteroidal anti-inflammatory drugs (NSAIDs) alone or in combination with other agents for preventing pancreatitis after endoscopic retrograde cholangiopanography. METHODS: We carried out a literature search of random controlled trials (RCTs) on preventing post-operative pancreatitis by administration of the anti-inflammatory drugs, indomethacin and diclofenac, following endoscopic retrograde cholangiopancreatography (ERCP). The databases searched for relevant publications up to July 7, 2021, included PubMed, Cochrane Library, and Embase. We screened the literature according to inclusion criteria and analyzed the extracted data. The overall population and high-risk patient groups were analyzed, with the main outcome being the incidence of PEP. RESULTS: The search identified 32 RCTs that included 15019 patients with post-ERCP pancreatitis and 9 different interventions. The results of the overall population network meta-analysis showed that NSAIDs alone, high-dose NSAIDs, and a combination of NSAIDs significantly reduced the incidence of PEP compared with placebo. However, compared with placebo, there was no statistically significant difference between the two interventions (NSAIDs + standard hydration and high-dose NSAIDs). In addition, NSAIDs + sublingual nitrates were associated with a lower incidence of PEP compared to that observed with NSAIDs alone. Probability ranking results showed that NSAIDs + sublingual nitrate had the best effect, followed by NSAIDs + standard hydration, NSAIDs + melatonin, NSAIDs + aggressive hydration, NSAIDs + somatostatin, NSAIDs alone, NSAIDs + epinephrine, high-dose NSAIDs, and placebo. In the high-risk subgroup, the results of the network meta-analysis showed that NSAIDs alone, high-dose NSAIDs, and a combination of NSAIDs showed no statistically significant difference in their ability to reduce the incidence of PEP compared with placebo. Probability ranking results showed that NSAIDs + hydration had the best effect, followed by NSAIDs + sublingual nitroglycerin and NSAIDs + aggressive hydration. CONCLUSION: Of the nine interventions, NSAIDs + sublingual nitrates had considerably better efficacy than the other drugs for reducing the incidence of PEP in the overall population. In high-risk patients, NSAIDs + standard hydration may be the best preventive treatment; however, more randomized, controlled trials are needed to validate our results. TRIAL REGISTRATION: Name of the registry: PROSPERO-International prospective register of systematic reviews. Unique identifying number or registration ID: CRD42021282205.


Assuntos
Melatonina , Pancreatite , Administração Retal , Anti-Inflamatórios não Esteroides/uso terapêutico , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Diclofenaco/uso terapêutico , Epinefrina , Humanos , Indometacina , Metanálise em Rede , Nitratos , Nitroglicerina , Pancreatite/etiologia , Pancreatite/prevenção & controle , Somatostatina , Revisões Sistemáticas como Assunto
19.
Front Immunol ; 13: 1013248, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466855

RESUMO

Background: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world with high morbidity and mortality. Identifying an effective marker for predicting the prognosis and therapeutic response is extremely meaningful. Angiogenesis-related genes (ARGs) play important roles in the tumor progression and immune-suppressive microenvironment formation. Methods: The differential expressed ARGs associated with the prognosis of HCC were identified in the TCGA dataset. Univariate Cox and least absolute shrinkage selection operator (LASSO) regression were applied to construct a ARGs Scoring model. The prognostic value of the ARGs Scoring model was assessed by Cox regression, Kaplan-Meier (KM) and ROC curve analyses. Then the model was further validated in an external dataset, ICGC dataset. The patients were split into two groups based on the ARGs Score and the clinical features were compared. TIMER, CIBERSORT and xCell algorithms were utilized to analyze the correlation between the ARGs Score and tumor immune microenvironment (TIME). Furthermore, we analyzed the efficacy of the model in predicting the therapeutic response for immunotherapy, targeted therapy and TACE treatment in different cohorts. Results: A total of 97 differential expressed ARGs were identified relating to the prognosis of HCC patients from the TCGA dataset. Then the ARGs Scoring model based on a 9-gene signature was constructed using the Cox and LASSO regression analyses. Higher ARGs Score had a poor clinical outcome and was considered to be an independent prognostic predictor for HCC in the multivariate Cox analysis. The ARGs Score was related to the enrichment of various immune cells, such as CD4+ T cells, Treg, macrophage, neutrophil and dendritic cells, exhibiting a more immunosuppressive phenotype. Higher ARGs Score was correlated with higher expression of immune checkpoint genes and poor response to immunotherapy. Furthermore, higher ARGs Score indicated poor therapeutic response in the sorafenib and TACE treatment cohorts, individually. Conclusions: The ARGs Scoring model exhibited robust predictive value for the prognosis and TIME for HCC patients. Higher ARGs Score indicated poor therapeutic response of the immunotherapy, sorafenib and TACE treatment. The ARGs Scoring model could be used as a biomarker to help physicians to develop more individualized treatment for HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Sorafenibe , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Prognóstico , Microambiente Tumoral/genética
20.
Bioengineered ; 13(4): 8617-8630, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35322735

RESUMO

Hepatocellular carcinoma (HCC) is a common malignancy in the world, with high mortality and poor prognosis. Hepatitis B virus (HBV) is one of the key factors implicated in the occurrence of HCC. Increasing evidence suggests that miRNAs play important roles in the development and metastasis of HBV-associated HCC (HBV-HCC). Here, we performed CCK8 (Cell count kit-8), EdU (5-ethynyl-2'-deoxyuridine) incorporation assay, wound-healing assay, transwell assay to study the changes in the cellular phenotype. Luciferase reporter assay, RNA pull-down experiment, RT-qPCR and western blotting were employed to study molecular mechanism. In addition, we also constructed a mouse HCC xenograft model to verify the functional role of HMMR-AS1/miR-627-3p/HMGA2 signal axis in vivo. Our study demonstrated that HMMR-AS1 was highly expressed in HCC tissues and cell lines, suggesting its implication in the progression of HCC. In addition, in vitro experiments showed that high HMMR-AS1 expression facilitated the migration, invasion, and proliferation of HCC cells. We further revealed that HMMR-AS1 promoted the malignant phenotype of HCC cells by regulating miR-627-3p/HMGA2 axis. Together, our data suggest that HMMR-AS1 regulates HBV-HCC progression via miR-627-3p/HMGA2 axis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , RNA Longo não Codificante , Animais , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Proteínas da Matriz Extracelular , Vírus da Hepatite B/genética , Humanos , Receptores de Hialuronatos , Neoplasias Hepáticas/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Antissenso , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
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