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1.
Sci Total Environ ; 938: 173521, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38802012

RESUMO

Forests are experiencing increasingly severe drought stress worldwide. Although most studies have quantified how tree growth was affected by extreme droughts, how trees recover from different drought intensities are still poorly understood for different species. We used a network of tree-ring data comprising 731 Quercus mongolica trees across 29 sites, 312 Larix olgensis Henry trees from 13 sites, and 818 Larix principis-rupprechtii trees from 34 sites, covering most of their distribution range in northern China, to compare the influences of drought intensity on post-drought recovery. The results showed that summer droughts had strong negative influences on tree growth. Post-drought growth varied with drought intensity for the three species. Larix species exhibited strong legacy effects after severe droughts, which is related to the lack of compensatory growth. In contrast, the compensatory growth of Q. mongolica reduced drought legacy effect. However, the compensatory growth of Q. mongolica gradually weaken with increasing drought intensity and disappeared during severe drought. Our findings indicated that influence of drought on Q. mongolica growth mainly shown in drought years, but Larix species suffered from long-term drought legacy effects, implying Q. mongolica rapidly recovered from droughts but Larix species need several years to recover from droughts, thus the two genera have different recovery strategy.


Assuntos
Secas , Florestas , Larix , Quercus , Larix/fisiologia , Quercus/fisiologia , Quercus/crescimento & desenvolvimento , China , Árvores/fisiologia , Resistência à Seca
2.
Eur J Med Res ; 29(1): 275, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38720374

RESUMO

BACKGROUND: Large skin lesions of the upper extremity tend to be ''long and narrow'' in shape, and the currently used repair and reconstruction protocols still have some drawbacks, including difficulty in closure of the donor area, poor cosmetic appearance of the donor and recipient areas, and low flap survival rates. The ilioinguinal flap has been more widely used for repair and reconstruction of various complex conditions. In order to improve the versatility of the flap design and to achieve better aesthetic results, we report a study on the improved design of Compound SCIP flap for repairing "long and narrow" large skin defects of the upper extremity by using a modified design of the ilioinguinal flap for the procurement of perforating blood vessels and flap excision. METHODS: From April 2005 to August 2015, a total of 12 patients underwent this modified design procedure, in which the anterior branch of the fourth lumbar artery or the posterior intercostal artery was selected to provide blood supply for the perforator flap together with the superficial branch of the superficial iliac artery to meet the blood supply needs of the flap for the one-time repair of a large "long and narrow" skin defect in the upper limb. Patient demographics, flap characteristics, and associated complications were retrospectively analyzed. RESULTS: 3 females and 9 males were included in this study, the mean age of the patients was 31.7 years (range, 22-44 years), the mean follow-up period was 15.3 ± 5.6 months (range, 7-24 months), and all patients had complete closure of the defect site and donor area, and all flaps survived. CONCLUSIONS: The Compound SCIP flap presents some advantages in repairing 'long and narrow' skin defects in the upper limb. While ensuring the survival rate of the elongated ilioinguinal flap, it amplifies the benefits of the ilioinguinal flap and enhances skin utilization. This can serve as a beneficial choice for repairing 'long and narrow' skin defects in the upper limb.


Assuntos
Procedimentos de Cirurgia Plástica , Extremidade Superior , Humanos , Feminino , Masculino , Adulto , Procedimentos de Cirurgia Plástica/métodos , Extremidade Superior/cirurgia , Pessoa de Meia-Idade , Retalhos Cirúrgicos , Estudos Retrospectivos , Retalho Perfurante , Idoso , Adulto Jovem , Pele
3.
Int J Mol Sci ; 24(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37108294

RESUMO

This study investigates the synthesis of a new compound, PYR26, and the multi-target mechanism of PYR26 inhibiting the proliferation of HepG2 human hepatocellular carcinoma cells. PYR26 significantly inhibits the growth of HepG2 cells (p < 0.0001) and this inhibition has a concentration effect. There was no significant change in ROS release from HepG2 cells after PYR26 treatment. The mRNA expressions of CDK4, c-Met and Bak genes in HepG2 cells were significantly inhibited (p < 0.05), while mRNA expression of pro-apoptotic factors such as caspase-3 and Cyt c was significantly increased (p < 0.01). The expression of PI3K, CDK4 and pERK proteins decreased. The expression level of caspase-3 protein was increased. PI3K is a kind of intracellular phosphatidylinositol kinase. PI3K signaling pathway is involved in signal transduction of a variety of growth factors, cytokines and extracellular matrix and plays an important role in preventing cell apoptosis, promoting cell survival and influencing cell glucose metabolism. CDK4 is a catalytic subunit of the protein kinase complex and is important for G1 phase progression of the cell cycle. PERK refers to phosphorylated activated ERK, which is translocated from cytoplasm to the nucleus after activation, and then participates in various biological reactions such as cell proliferation and differentiation, cell morphology maintenance, cytoskeleton construction, cell apoptosis and cell canceration. Compared with the model group and the positive control group, the tumor volume of the nude mice in the low-concentration PYR26 group, the medium-concentration group and the high-concentration group was smaller, and the organ volume was smaller than that in the model group and the positive control group. The tumor inhibition rates of low-concentration group PYR26, medium-concentration group and high-concentration group reached 50.46%, 80.66% and 74.59%, respectively. The results showed that PYR26 inhibited the proliferation of HepG2 cells and induced apoptosis of HepG2 cells by down-regulating c-Met, CDK4 and Bak, up-regulating the mRNA expression of caspase-3 and Cyt c genes, down-regulating PI3K, pERK and CDK4 proteins and up-regulating the protein level of caspase-3. In a certain range, with the increase in PYR26 concentration, the tumor growth was slower and the tumor volume was smaller. Preliminary results showed that PYR26 also had an inhibitory effect on the tumors of Hepa1-6 tumor-bearing mice. These results suggest that PYR26 has an inhibitory effect on the growth of liver cancer cells, therefore it has potential to be developed into a new anti-liver cancer drug.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Caspase 3/genética , Caspase 3/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Camundongos Nus , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Células Hep G2 , Apoptose , Proliferação de Células , RNA Mensageiro
4.
Artigo em Inglês | MEDLINE | ID: mdl-36981695

RESUMO

PM2.5 is the main cause of haze pollution, and studying its spatio-temporal distribution and driving factors can provide a scientific basis for prevention and control policies. Therefore, this study uses air quality monitoring information and socioeconomic data before and during the COVID-19 outbreak in 18 prefecture-level cities in Henan Province from 2017 to 2020, using spatial autocorrelation analysis, ArcGIS mapping, and the spatial autocorrelation analysis. ArcGIS mapping and the Durbin model were used to reveal the characteristics of PM2.5 pollution in Henan Province in terms of spatial and temporal distribution characteristics and analyze its causes. The results show that: (1) The annual average PM2.5 concentration in Henan Province fluctuates, but decreases from 2017 to 2020, and is higher in the north and lower in the south. (2) The PM2.5 concentrations in Henan Province in 2017-2020 are positively autocorrelated spatially, with an obvious spatial spillover effect. Areas characterized by a high concentration saw an increase between 2017 and 2019, and a decrease in 2020; values in low-concentration areas remained stable, and the spatial range showed a decreasing trend. (3) The coefficients of socio-economic factors that increased the PM2.5 concentration were construction output value > industrial electricity consumption > energy intensity; those with negative effects were: environmental regulation > green space coverage ratio > population density. Lastly, PM2.5 concentrations were negatively correlated with precipitation and temperature, and positively correlated with humidity. Traffic and production restrictions during the COVID-19 epidemic also improved air quality.


Assuntos
Poluição do Ar , COVID-19 , Epidemias , Material Particulado , Humanos , Poluição do Ar/análise , China/epidemiologia , Cidades , COVID-19/epidemiologia , Monitoramento Ambiental/métodos , Material Particulado/análise , Fatores Socioeconômicos , Análise Espaço-Temporal
5.
Sci Total Environ ; 848: 157808, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-35932855

RESUMO

Forests are facing climate changes such as warmer temperatures, accelerated snowmelt, increased drought, as well as changing diurnal temperature ranges (DTR) and cloud cover regimes. How tree growth is influenced by the changes in daily to monthly temperatures and its associations with droughts has been extensively investigated, however, few studies have focused on how changes in sub-daily temperatures i.e., DTR, influence tree growth during drought events. Here, we used a network of Larix principis-rupprechtii tree-ring data from 1989 to 2018, covering most of the distribution of planted larch across North China, to investigate how DTR, cloud cover and their interactions influence the relationship between drought stress and tree growth. DTR showed a negative correlation with larch growth in 95 % of sites (rmean = -0.30, significant in 42 % of sites). Cloud cover was positively correlated with growth in 87 % of sites (rmean = 0.13, significant in 5 % of sites). Enhanced tree growth was found at lower DTR in the absence of severe drought. Our findings highlight that in the absence of severe droughts, reduced DTR benefits tree growth, while increased cloud cover tended to benefit tree growth only during severe drought periods. Given how DTR influences drought impacts on tree growth, net tree growth was found to be larger in regions with smaller DTR.


Assuntos
Larix , China , Mudança Climática , Secas , Florestas , Temperatura , Árvores
6.
Artigo em Inglês | MEDLINE | ID: mdl-35522016

RESUMO

OBJECTIVES: The paediatric tracheobronchial inflammatory myofibroblastic tumour (IMT) is a rare disease. Whether limited surgical resection is a feasible surgical approach for these patients remains controversial. The objectives of this study were to report the long-term prognosis after limited surgical resections on paediatric tracheobronchial IMT and provide a surgical management strategy for this rare disease. METHODS: Paediatric tracheobronchial IMT patients who underwent limited surgical resection from 2012 to 2020 were enrolled in this study. The clinical characteristics, course of treatment and long-term outcomes of all participants were collated. We presented the accumulated data and analysed the feasibility of limited surgical resection on the paediatric tracheobronchial IMT. RESULTS: A total of 9 children with tracheobronchial IMTs were enrolled in our study. Cough and shortness of breath were the most common symptoms. All 9 participants underwent surgical treatment, including 2 tracheal reconstructions, 4 carinal reconstructions and 3 bronchial sleeve resections. Among the participants, 6/9 (66%) were positive for the anaplastic lymphoma receptor tyrosine kinase gene in terms of immunohistochemistry. None of the participants died of short-term complications. The follow-up period was 5.4 (range, 1.1-9.3) years, during which all participants remained well. CONCLUSIONS: Limited surgical resection is preferred for paediatrics with tracheobronchial IMTs. Meanwhile, patients with complete resection have an excellent long-term prognosis.


Assuntos
Granuloma de Células Plasmáticas , Neoplasias , Pediatria , Brônquios , Criança , Humanos , Pneumonectomia , Doenças Raras
7.
Chem Biodivers ; 19(6): e202200189, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35510593

RESUMO

A series of novel quinazolinone hydrazide derivatives were designed and synthesized as EGFR inhibitors. The results indicated that most of the aimed compounds had potential anti-tumor cell proliferation and EGFR inhibitory activities. In the comprehensive analysis of all the tested compounds, the target compound 9c showed the best anti-tumor cell proliferation activity, (IC50 =1.31 µM for MCF-7, IC50 =1.89 µM for HepG2, IC50 =2.10 µM for SGC), and IC50 =0.59 µM for the EGFR inhibitory activity. Docking results showed that compound 9c could ideally insert the active site and interact with the critical amino acid residues (Val702, Lys721, Met769, Asp831) in the active site.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/química , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB , Humanos , Hidrazinas/farmacologia , Simulação de Acoplamento Molecular , Estrutura Molecular , Inibidores de Proteínas Quinases/química , Quinazolinonas/química , Relação Estrutura-Atividade
8.
Molecules ; 27(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35268655

RESUMO

In this paper, we report the design, synthesis and biological evaluation of a novel S-allyl-l-cysteine (SAC) and gallic acid conjugate S-(4-fluorobenzyl)-N-(3,4,5-trimethoxybenzoyl)-l-cysteinate (MTC). We evaluate the effects on ischemia-reperfusion-induced PC12 cells, primary neurons in neonatal rats, and cerebral ischemic neuronal damage in rats, and the results showed that MTC increased SOD, CAT, GPx activity and decreased LDH release. PI3K and p-AKT protein levels were significantly increased by activating PI3K/AKT pathway. Mitochondrial pro-apoptotic proteins Bax and Bim levels were reduced while anti-apoptotic protein Bcl-2 levels were increased. The levels of cleaved caspase-9 and cleaved caspase-3 were also reduced in the plasma. The endoplasmic reticulum stress (ERS) was decreased, which in turns the survival rate of nerve cells was increased, so that the ischemic injury of neurons was protected accordingly. MTC activated the MEK-ERK signaling pathway and promoted axonal regeneration in primary neurons of the neonatal rat. The pretreatment of MEK-ERK pathway inhibitor PD98059 and PI3K/AKT pathway inhibitor LY294002 partially attenuated the protective effect of MTC. Using a MCAO rat model indicated that MTC could reduce cerebral ischemia-reperfusion injury and decrease the expression of proinflammatory factors. The neuroprotective effect of MTC may be due to inhibition of the over-activation of the TREK-1 channel and reduction of the current density of the TREK1 channel. These results suggested that MTC has a protective effect on neuronal injury induced by ischemia reperfusion, so it may have the potential to become a new type of neuro-ischemic drug candidate.


Assuntos
Fosfatidilinositol 3-Quinases
9.
Curr Top Med Chem ; 22(7): 550-560, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35168506

RESUMO

Human carbonic anhydrase (CA) IX is a tumor-associated protein since it is scarcely present in normal tissues but highly overexpressed in a large number of solid tumors, where it actively contributes to survival and metastatic spread of tumor cells. A variety of approaches and design strategies were reported that afford CA IX/XII specific inhibitors and avoid the compromising effects of isoforms-promiscuous compounds. CA IX inhibitors hybrids/conjugates have become an important scaffold to design therapeutic agents with both CA inhibition and anti-cancer effects. In this review, we firstly present an overview of the role of CA IX in hypoxic tumors physiopathology, then provide a comprehensive update on the rational design and synthesis of small molecule CA IX inhibitors discovered since 2019. Also, their structure-activity relationship analysis studies are covered. A brief description of applications for CA IX inhibition in other therapeutic areas is also provided.


Assuntos
Antineoplásicos , Neoplasias , Antígenos de Neoplasias/metabolismo , Antígenos de Neoplasias/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Anidrase Carbônica IX/metabolismo , Inibidores da Anidrase Carbônica/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Relação Estrutura-Atividade
10.
Crit Rev Anal Chem ; 52(2): 250-274, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32715731

RESUMO

Mercury is a highly toxic and non-essential element that is found in every corner of the globe. The small amount of mercury produced by various pathways eventually enters freshwater and marine ecosystems, circulating through the food chain (especially fish) and causing various environmental problems in aspects including plants, animals, and human. There are several traditional quantitative methods developed for mercury ions (II) analysis in water samples. However, due to the complexity of the detection process, high cost and strong technical expertise, it is difficult to detect mercury ions in real-time. Therefore, in recent years, a large number of researchers have developed small-molecule fluorescent probes for Hg ions detection. Fluorimetry has the advantages of convenient detection, short response time, high sensitivity and good selectivity. This review summarized the small-molecule fluorescent probes for mercuric ion detection developed in recent years according to the chemical structural classification, compared their performances and elaborated the mechanism. We hope that the review will help the researches for the designs of metal ions fluorescent probes and their applications with certain reference value.


Assuntos
Mercúrio , Animais , Ecossistema , Corantes Fluorescentes/química , Humanos , Íons/análise , Mercúrio/análise , Mercúrio/química
11.
Sensors (Basel) ; 21(19)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34640646

RESUMO

Hypochlorous acid (HOCl) generates from the reaction between hydrogen peroxide and chloride ions via myeloperoxidase (MPO)-mediated in vivo. As very important reactive oxygen species (ROS), hypochlorous acid (HOCl)/hypochlorite (OCl-) play a crucial role in a variety of physiological and pathological processes. However, excessive or misplaced production of HOCl/OCl- can cause variety of tissue damage and human diseases. Therefore, rapid, sensitive, and selective detection of OCl- is very important. In recent years, the fluorescent probe method for detecting hypochlorous acid has been developed rapidly due to its simple operation, low toxicity, high sensitivity, and high selectivity. In this review, the progress of recently discovered fluorescent probes for the detection of hypochlorous acid was summarized with the aim to provide useful information for further design of better fluorescent probes.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Humanos , Peróxido de Hidrogênio , Peroxidase
12.
Sci Adv ; 7(44): eabj0200, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34705507

RESUMO

Grid cells and theta oscillations are fundamental constituents of the brain's navigation system and have been described in the entorhinal cortex (EC). Recent fMRI studies reveal that the ventromedial prefrontal cortex (vmPFC) contains grid-like representations. However, the neural mechanisms underlying human vmPFC grid-like representations and their interactions with EC grid activity have remained unknown. We conducted intracranial electroencephalography (iEEG) recordings from epilepsy patients during a virtual spatial navigation task. Oscillatory theta power in the vmPFC exhibited a sixfold rotational symmetry that was coordinated with grid-like representations in the EC. We found that synchronous theta oscillations occurred between these regions that predicted navigational performance. Analysis of information transfer revealed a unidirectional signal from vmPFC to EC during memory retrieval. Together, this study provides insights into the previously unknown neural signature and functional role of grid-like representations outside the EC and their synchronization with the entorhinal grid during human spatial navigation.

13.
Bioorg Chem ; 116: 105342, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34536928

RESUMO

Thiazolidinedione (TZD) is a novel peroxides proliferator activated receptor γ (PPARγ) agonist with many side effects. Herein, we developed a series of novel TZD analogues as partial agonists targeting PPARγ. The study of anti-hyperglycemic activity and anti-inflammatory activity enabled us to identify a novel compound, 4 g, which quickly recover the blood glucose of mice at the concentration of 100 mg/kg, and show similar anti-inflammatory activity to ibuprofen at the concentration of 20 mg/kg. The competitive binding assay confirmed direct binding of 4 g to the LBD of PPARγ with IC50 being 1790 nM, and dose-dependently increased the transcriptional activity of PPARγ. Besides, through computer-aided drug design software simulation docking, it was found that compound 4 g showed the best binding ability to target protein PPARγ. Furthermore, because of the introduction of benzene containing group at N3 position, the stability of H12 in the active pocket is reduced and the stability of H3 and ß-fold is increased, showing the characteristics of some PPARγ agonists, based on the docking model analysis. Together, these results suggest that 4 g is a promising PPARγ agonist that deserves further investigation.


Assuntos
Desenho de Fármacos , PPAR gama/agonistas , Tiazolidinedionas/farmacologia , Relação Dose-Resposta a Droga , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Software , Relação Estrutura-Atividade , Tiazolidinedionas/síntese química , Tiazolidinedionas/química
14.
Materials (Basel) ; 14(11)2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067370

RESUMO

In this study, the hydrated sodium aluminosilicate material was synthesized by one-step hydrothermal alkaline desilication using fly ash (FA) as raw material. The synthesized materials were characterized by XRD, XRF, FT-IR and SEM. The characterization results showed that the alkali-soluble desilication successfully had synthesized the sodium aluminosilicate crystalline (N-A-S-H) phase of sodalite-type (SOD), and the modified material had good ionic affinity and adsorption capacity. In order to figure out the suitability of SOD as an adsorbent for the removal of ammonium and phosphorus from wastewater, the effects of material dosing, contact time, ambient pH and initial solute concentration on the simultaneous removal of ammonium and phosphorus are investigated by intermittent adsorption tests. Under the optimal adsorption conditions, the removal rate of ammonium was 73.3%, the removal rate of phosphate was 85.8% and the unit adsorption capacity reached 9.15 mg/L and 2.14 mg/L, respectively. Adsorption kinetic studies showed that the adsorption of ammonium and phosphorus by SOD was consistent with a quasi-secondary kinetic model. The adsorption isotherm analysis showed that the equilibrium data were in good agreement with the Langmuir and Freundlich model. According to thermodynamic calculations, the adsorption of ammonium and phosphorus was found to be a heat-absorbing and spontaneous process. Therefore, the preparation of SOD by modified FA has good adsorption properties as adsorbent and has excellent potential for application in the removal of contaminants from wastewater.

15.
Curr Med Chem ; 28(34): 6977-6989, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33797359

RESUMO

Focal Adhesion Kinase (FAK) is a non-receptor tyrosine kinase involved in the process of cell proliferation, survival, migration, and invasion. It has become a promising therapeutic target for the treatment of human metastatic cancers due to its overexpression and/or activation in multiple cancer types. Since FAK is emerging as a potential cancer target because of its overexpression at both the transcriptional and translational level in cancer, different types of FAK inhibitors with diversified scaffolds have been discovered in the past few years. In this review, the progress of recently discovered small molecule FAK inhibitors was summarized. Major efforts have been focused on the rational design and synthesis of small molecule FAK inhibitors, and their structure-activity relationship (SAR) analysis wasalso discussed. Among them, while type I inhibitors remain as the major focuses, type II inhibitors and novel allosteric FAK inhibitors (type III inhibitors) have been developed to improve both potency and selectivity. Meanwhile, novel strategies, such as targeting FAK using inhibitors of protein-protein interactions, were also discovered. Lastly, some insights and perspectives on the future development of FAK inhibitors as anticancer therapeutics have been provided.


Assuntos
Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Neoplasias , Inibidores de Proteínas Quinases , Proliferação de Células , Humanos , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Relação Estrutura-Atividade
16.
Expert Rev Med Devices ; 18(1): 107-120, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33305643

RESUMO

Background: Based on our Phantom study on transcranial direct current stimulation (tDCS), we hypothesized that EEG band power and field confinement would be greater following left dorsolateral prefrontal cortex (DLPFC - F3) tDCS using circular vs. rectangular electrodes.Methods: Double-blind-randomized trial comparing tDCS with anode over left DLPFC (groups: rectangular electrodes, circular electrodes, sham) and 2 active subgroup references (right shoulder vs. right DLPFC).Results: Twenty-four randomized participants were assessed. We indeed found higher average EEG power spectral density (PSD) across bands for circular vs. rectangular electrodes, largely confined to F3 and there was a significant increase at AF3 for low alpha (p = 0.037). Significant differences included: increased PSD in low beta (p = 0.024) and theta bands (p = 0.021) at F3, and in theta (p = 0.036) at FC5 for the right DLPFC vs. shoulder with no coherence changes. We found PSD differences between active vs. sham tDCS at Fz for alpha (p = 0.043), delta (p = 0.036), high delta (p = 0.030); and at FC1 for alpha (p = 0.031), with coherence differences for F3-Fz in beta (p = 0.044), theta (p = 0.044), delta (p = 0.037) and high delta (p = 0.009).Conclusion: This pilot study despite low statistical power given its small sample size shows that active left DLPFC tDCS modulates EEG frontocentrally and suggests that electrode shapes/reference locations affect its neurophysiological effects, such as increased low alpha power at AF3 using circular vs. rectangular electrodes. Further research with more participants is warranted.


Assuntos
Eletroencefalografia , Voluntários Saudáveis , Estimulação Transcraniana por Corrente Contínua , Adulto , Método Duplo-Cego , Eletrodos , Feminino , Humanos , Masculino , Projetos Piloto , Córtex Pré-Frontal/diagnóstico por imagem , Estimulação Transcraniana por Corrente Contínua/efeitos adversos , Adulto Jovem
17.
Front Hum Neurosci ; 13: 388, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31736732

RESUMO

BACKGROUND: Transcranial direct current stimulation (tDCS) modulates neural networks. Computer simulations, while used to identify how currents behave within tissues of different conductivity properties, still need to be complemented by physical models. OBJECTIVE/HYPOTHESIS: To better understand tDCS effects on biology-mimicking tissues by developing and testing the feasibility of a high-fidelity 3D head phantom model that has sensing capabilities at different compartmental levels. METHODS: Models obtained from MRI images generated 3D printed molds. Agar phantoms were fabricated, and 18 monitoring electrodes were placed on specific phantom brain areas. RESULTS: When using rectangular electrodes, the measured and simulated voltages at the monitoring electrodes agreed reasonably well, except at excitation locations. The electric field distribution in different phantom layers appeared better confined with circular electrodes compared to rectangular electrodes. CONCLUSION: The high-fidelity 3D head model was found to be feasible and comparable with computer-based electrical simulations, with high correlation between simulated and measured brain voltages. This feasibility study supports testing to further assess the reliability of this model.

18.
Curr Top Med Chem ; 19(15): 1276-1288, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31526339

RESUMO

C-Met, also referred to as Hepatocyte Growth Factor Receptor (HGFR), is a heterodimeric receptor tyrosine kinase. It has been determined that c-Met gene mutations, overexpression, and amplification also occur in a variety of human tumor types, and these events are closely related to the aberrant activation of the HGF/c-Met signaling pathway. Meanwhile, high c-Met expression is closely associated with poor prognosis in cancer patients. The c-Met kinase has emerged as an attractive target for developing antitumor agents. In this review, we cover the recent advances on the small molecule c-Met inhibitors discovered from 2018 until now, with a main focus on the rational design, synthesis and structureactivity relationship analysis.


Assuntos
Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas c-met/metabolismo , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química
19.
ACS Appl Mater Interfaces ; 11(23): 20678-20688, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31081332

RESUMO

Responsive nanocarriers with biocompatibility and precise drug releasing capability have emerged as a prospective candidate for anticancer treatment. However, the challenges imposed by the complicated preparation process and limited loading capacities have seriously impeded the development of novel multifunctional drug delivery systems. Here, we developed a novel and dual-responsive nanocarrier based on a nanoscale ZIF-8 core and an organosilica shell containing disulfide bridges in its frameworks through a facile and efficient strategy. The prepared ZIF-8@DOX@organosilica nanoparticles (ZDOS NPs) exhibited a well-defined structure and excellent doxorubicin (DOX) loading capability (41.2%) with pH and redox dual-sensitive release properties. The degradation of the organosilica shell was observed after 12 h incubation with a 10 mM reducing agent. Confocal imaging and flow cytometry analysis further proved that the nanocarriers can efficiently enter cells and complete intracellular DOX release under the low pH and high glutathione concentrations, which resulted in an enhanced cytotoxicity of DOX for cancer cells. Meanwhile, subcellular localization experiments revealed that the ZDOS NPs entered cells mainly by endocytosis and then escaped from lysosomes into the cytosol. Moreover, in vivo assays also demonstrated that the ZDOS NPs exhibited negligible systemic toxicity and significantly enhanced anticancer efficiencies compared with free DOX. In summary, our prepared pH and redox dual-responsive nanocarriers provide a potential platform for controlled release and cancer treatment.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Estruturas Metalorgânicas/química , Nanopartículas/química , Dióxido de Silício/química , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Citometria de Fluxo , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Bioorg Med Chem ; 27(8): 1509-1516, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30846404

RESUMO

A series of rhodanine derivatives RB1-RB23 were synthesized through a two-round screening. Their Mycobacterial tuberculosis (Mtb) InhA inhibitory activity and Mtb growth blocking capability were evaluated. The most potent hit compound RB23 indicated comparable InhA inhibiton (IC50 = 2.55 µM) with the positive control Triclosan (IC50 = 6.14 µM) and Isoniazid (IC50 = 8.29 µM). Its improved growth-blocking effect on Mtb and low toxicity were attractive for further development. The docking simulation revealed the possible binding pattern of this series and picked the key interacted residues as Ser20, Phe149, Lys165 and Thr196. The 3D-QSAR model visualized the SAR discussion and hinted new information. Modifying the surroundings near rhodanine moiety might be promising attempts in later investigations.


Assuntos
Proteínas de Bactérias/metabolismo , Oxirredutases/metabolismo , Rodanina/química , Antituberculosos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Sítios de Ligação , Avaliação Pré-Clínica de Medicamentos , Isoniazida/farmacologia , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/metabolismo , Oxirredutases/antagonistas & inibidores , Estrutura Terciária de Proteína , Relação Quantitativa Estrutura-Atividade , Rodanina/metabolismo , Rodanina/farmacologia
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