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1.
Cell ; 187(1): 184-203.e28, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38181741

RESUMO

We performed comprehensive proteogenomic characterization of small cell lung cancer (SCLC) using paired tumors and adjacent lung tissues from 112 treatment-naive patients who underwent surgical resection. Integrated multi-omics analysis illustrated cancer biology downstream of genetic aberrations and highlighted oncogenic roles of FAT1 mutation, RB1 deletion, and chromosome 5q loss. Two prognostic biomarkers, HMGB3 and CASP10, were identified. Overexpression of HMGB3 promoted SCLC cell migration via transcriptional regulation of cell junction-related genes. Immune landscape characterization revealed an association between ZFHX3 mutation and high immune infiltration and underscored a potential immunosuppressive role of elevated DNA damage response activity via inhibition of the cGAS-STING pathway. Multi-omics clustering identified four subtypes with subtype-specific therapeutic vulnerabilities. Cell line and patient-derived xenograft-based drug tests validated the specific therapeutic responses predicted by multi-omics subtyping. This study provides a valuable resource as well as insights to better understand SCLC biology and improve clinical practice.


Assuntos
Neoplasias Pulmonares , Proteogenômica , Carcinoma de Pequenas Células do Pulmão , Humanos , Linhagem Celular , Neoplasias Pulmonares/química , Neoplasias Pulmonares/genética , Carcinoma de Pequenas Células do Pulmão/química , Carcinoma de Pequenas Células do Pulmão/genética , Xenoenxertos , Biomarcadores Tumorais/análise
2.
Small ; 20(15): e2306237, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009589

RESUMO

Manganese-based materials are regarded as the most prospective cathode materials because of their high natural abundance, low toxicity, and high specific capacity. Nevertheless, the low conductivity, poor cycling performance, and controversial energy storage mechanisms hinder their practical application. Here, the MnS0.5Se0.5 microspheres are synthesized by a two-step hydrothermal approach and employed as cathode materials for aqueous zinc-ion batteries (AZIBs) for the first time. Interestingly, in-depth ex situ tests and electrochemical kinetic analyses reveal that MnS0.5Se0.5 is first irreversibly converted into low-crystallinity ZnMnO3 and MnOx by in situ electrooxidation (MnS0.5Se0.5-EOP) during the first charging process, and then a reversible co-insertion/extraction of H+/Zn2+ occurs in the as-obtained MnS0.5Se0.5-EOP electrode during the subsequent discharging and charging processes. Benefiting from the increased surface area, shortened ion transport path, and stable lamellar microsphere structure, the MnS0.5Se0.5-EOP electrodes deliver high reversible capacity (272.8 mAh g-1 at 0.1 A g-1), excellent rate capability (91.8 mAh g-1 at 2 A g-1), and satisfactory cyclic stability (82.1% capacity retention after 500 cycles at 1 A g-1). This study not only provides a powerful impetus for developing new types of manganese-based chalcogenides, but also puts forward a novel perspective for exploring the intrinsic mechanisms of in situ electrooxidation behavior.

3.
Phys Chem Chem Phys ; 26(11): 8784-8793, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38420852

RESUMO

The homogeneous condensation of water vapor at ambient temperature is studied using molecular dynamics simulation. We reveal that there is a droplet size at the nanoscale where water droplets can be stabilized in the condensation process. Our simulations show that the growth of water droplets is dominated by collision and coagulation between small water droplets after nucleation. This process is found to be accompanied by exceptionally fast evaporation such that droplet growth is balanced by evaporation when water droplets grow to a critical size, approximately 12.5 Å in radius, reaching a stable size distribution. The extremely high evaporation rate is attributed to the curvature dependence of surface tension. Surface tension shows a significant decrease with decreasing droplet size below 20 Å, which causes the total free energy of nanoscaled water droplets to rise after collision and coagulation. Consequently, water droplets have to shrink via fast evaporation. The curvature dependence of surface tension is related to the dielectric ordering of water molecules near the surface of water droplets. Owing to fast evaporation, secondary condensation occurs, and many small water clusters form, ultimately exhibiting a bimodal distribution of water-droplet size.

4.
Acta Biochim Biophys Sin (Shanghai) ; 55(6): 948-955, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37249335

RESUMO

Small cell lung cancer (SCLC) accounts for approximately 15% of all lung cancer cases and features a strong predilection for early metastasis and extremely poor prognosis. Despite being highly sensitive to chemotherapy and/or radiotherapy initially, most SCLC patients develop therapeutic resistance within one year and die of distant metastases. Multiple studies have revealed the high heterogeneity and strong plasticity of SCLC associated with frequent metastases and early development of therapeutic resistance as well as poor clinical outcome. Importantly, different SCLC subtypes are associated with different therapeutic vulnerabilities, and the inflamed subtype tends to have the best response to immunotherapy, which highlights the importance of precision medicine in the clinic. Here, we review recent advances in SCLC heterogeneity and plasticity and their link to distant metastases and chemotherapy resistance. We hope that a better understanding of the molecular mechanisms underlying SCLC malignant progression will help to develop better intervention strategies for this deadly disease.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/patologia , Neoplasias Pulmonares/patologia
5.
Environ Monit Assess ; 195(12): 1423, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37934331

RESUMO

Industrial wastewater from drug production is one of the contributors to water pollution. For drug wastewater treatment, photodegradation-based chemical technology has gained more attention because of the drug's microbicidal nature and stability. A zinc-chromium-nickel trimetallic-layered double hydroxide compounding with graphene oxide catalyst (ZnCrNi/GO) was synthesized and exhibited a clustered crumb sheet morphology. The prepared catalyst was characterized by a scanning electron microscope (SEM) equipped with an energy-dispersive X-ray spectrometer (EDS), Fourier transform infrared (FTIR) spectra, and X-ray photoelectron spectroscopy (XPS). The results of material analysis established the crystallographic structures of catalysts and evidenced the successful synthesis. The ZnCrNi/GO nanohybrid revealed a higher activity of approximately 90% degradation of tolysin under high-pressure mercury lamp irradiation. The optimized condition of the catalyst dosage of 500 mg/L and the natural pH of the solution at 7.0 under the tylosin concentration of 10 mg/L with high photocatalytic efficiency was explored. In addition, the main reactive species involved in this photocatalysis degradation were explored as the active cavity h+ and ·O2- to a certain extent by the radical trapping experiments. Reuse experiments have shown that as-prepared catalysts possessed the properties of high efficiency and long-lasting catalytic performance, which could meet pharmaceutical wastewater treatment. A three-metal-layered double hydroxide composed by the metal of Ni, Zn, and Cr was synthesized and attached onto graphene oxide. The catalytic materials obtained in this way have a significant catalysis efficiency to tylosin with the likely degradation mechanism of the active cavity h+ and the oxidative capacity of hydroxyl radials.


Assuntos
Monitoramento Ambiental , Tilosina , Hidróxidos
6.
Funct Integr Genomics ; 23(1): 24, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36576616

RESUMO

Colorectal cancer (CRC) is one of the most common malignancies worldwide; however, the potentially possible molecular biological mechanism of CRC is still not completely comprehended. This study aimed to confirm candidate key hub genes involved in the growth and development of CRC and their connection with immune infiltration as well as the related pathways. Gene expression data were selected from the GEO dataset. Hub genes for CRC were identified on the basis of differential expression analysis, weighted gene co-expression network analysis (WGCNA), and LASSO regression. Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Gene Set Enrichment Analysis (GSEA) were applied to reveal possible functions of the differential genes. Single-sample GSEA (ssGSEA) was implemented to identify the relationship between immune cells infiltration and hub genes. Two hundred and sixty-two differentially expressed genes (DEGs) were identified. Three modules were acquired based on WGCNA, and the blue module presented the highest relevance with CRC. Ten hub genes (AQP8, B3GALT5, CDH3, CEMIP, CPM, FOXQ1, PLAC8, SCNN1B, SPINK5, and SST) were acquired with LASSO analysis as underlying biomarkers for CRC. Compared with normal tissues, CRC tissues presented significantly higher numbers of CD4 T cells, CD8 T cells, B cells, natural regulatory T (Treg) cells, and monocytes. The functional enrichment analyses demonstrated that hub genes were primarily enriched in metabolic process, inflammatory-related, and immune-related response. Ten hub genes were identified to be involved in the occurrence and development of CRC and may be deemed as novel biomarkers for clinical diagnosis and treatment.


Assuntos
Neoplasias Colorretais , Perfilação da Expressão Gênica , Humanos , Biomarcadores , Ontologia Genética , Aprendizado de Máquina , Neoplasias Colorretais/genética , Redes Reguladoras de Genes , Fatores de Transcrição Forkhead , Proteínas
7.
Colorectal Dis ; 24(11): 1273-1284, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35735261

RESUMO

AIM: The aim was to evaluate the efficacy of transanal drainage tube (TDT) placement for preventing anastomotic leakage after low anterior resection for rectal cancer. METHOD: PubMed, the Cochrane Central Register of Controlled Trials, Embase and ClinicalTrials.gov databases were searched up to October 2021. Studies comparing outcomes following low anterior resection with or without TDT were included. The primary outcomes measured were anastomotic leakage rate, reoperation rate and anastomotic bleed rate. RESULTS: Three randomized controlled trials (RCTs) and 16 observational studies (prospective or retrospective) involving 4560 patients satisfied the basic inclusion criteria. In RCTs, a TDT was associated with no statistically significant differences in anastomotic leakage (OR = 0.67, 95% CI 0.42-1.05, P = 0.08), reduction in reoperation (OR = 0.11, 95% CI 0.03-0.51, P = 0.004) and increased anastomotic bleeding rate (OR = 2.36, 95% CI 1.11-5.01, P = 0.03). In observational studies, a TDT was associated with significant reduction in anastomotic leak (OR = 0.44, 95% CI 0.30-0.64, P < 0.0001) and reoperation (OR = 0.47, 95% CI 0.33-0.69, P < 0.0001), with no statistically significant differences in anastomotic bleeding (OR = 1.30, 95% CI 0.20-8.30, P = 0.78). CONCLUSION: In RCTs, a TDT for rectal cancer was correlated with no detectable differences in anastomotic leakage and with an increased risk of anastomotic bleeding. In observational studies, a TDT was correlated with reduction in anastomotic leakage and no detectable differences in anastomotic bleeding. Both RCTs and observational studies demonstrated a comparable reduction in reoperation rate with TDT. These data in aggregate indicated that TDTs may not show superiority but emphasized differences between RCT and observational data.


Assuntos
Protectomia , Neoplasias Retais , Humanos , Fístula Anastomótica/etiologia , Fístula Anastomótica/prevenção & controle , Anastomose Cirúrgica/efeitos adversos , Neoplasias Retais/complicações , Protectomia/efeitos adversos , Drenagem , Estudos Retrospectivos
8.
J Chem Phys ; 157(21): 214703, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36511537

RESUMO

The rotational dynamics of water near the ice/water interface and its relation with the crystal growth of ice are investigated by using molecular dynamics simulations. We find that the dipole-moment profiles of water adjacent to interfaces display an oscillation behavior, which is in contrast to the monotonic decay near the free surface for water films. This dielectric oscillation phenomenon is associated with the strong response to hard solid/water interface. It significantly suppresses the dielectric relaxation and slows down the rotational diffusion near the interface compared to bulk water. We propose that the rotational diffusion determines the active degree of growth sites on interfaces, and its slowdown due to the interfacial dielectric oscillation contributes to reducing the growth rate of ice. With this idea, we predict the crystal growth rate of ice based on the modified Wilson-Frenkel model involving rotational dynamics. The theoretical result agrees well with the simulation.

9.
Int J Mol Sci ; 23(18)2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36142812

RESUMO

Pinellia ternata (Thunb.) Druce is a traditional medicinal plant containing a variety of alkaloids, which are important active ingredients. Brassinolide (BR) is a plant hormone that regulates plant response to environmental stress and promotes the accumulation of secondary metabolites in plants. However, the regulatory mechanism of BR-induced alkaloid accumulation in P. ternata is not clear. In this study, we investigated the effects of BR and BR biosynthesis inhibitor (propiconazole, Pcz) treatments on alkaloid biosynthesis in the bulbil of P. ternata. The results showed that total alkaloid content and bulbil yield was enhanced by 90.87% and 29.67% under BR treatment, respectively, compared to the control. We identified 818 (476 up-regulated and 342 down-regulated) and 697 (389 up-regulated and 308 down-regulated) DEGs in the BR-treated and Pcz-treated groups, respectively. Through this annotated data and the Kyoto encyclopedia of genes and genomes (KEGG), the expression patterns of unigenes involved in the ephedrine alkaloid, tropane, piperidine, pyridine alkaloid, indole alkaloid, and isoquinoline alkaloid biosynthesis were observed under BR and Pcz treatments. We identified 11, 8, 2, and 13 unigenes in the ephedrine alkaloid, tropane, piperidine, and pyridine alkaloid, indole alkaloid, and isoquinoline alkaloid biosynthesis, respectively. The expression levels of these unigenes were increased by BR treatment and were decreased by Pcz treatment, compared to the control. The results provided molecular insight into the study of the molecular mechanism of BR-promoted alkaloid biosynthesis.


Assuntos
Alcaloides , Pinellia , Alcaloides/metabolismo , Brassinosteroides , Efedrina , Perfilação da Expressão Gênica , Isoquinolinas/metabolismo , Pinellia/genética , Piperidinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Piridinas/metabolismo , Esteroides Heterocíclicos , Transcriptoma , Tropanos
10.
Int J Mol Sci ; 23(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36499701

RESUMO

Brassinolide (BR) is the "sixth class" plant hormone, which plays an important role in various physiological and biochemical processes of plants. The wide variety of functions of Pinellia ternata means that there is huge demand for it and thus it is in short supply. This paper mainly assessed the changes of yield and quality in P. ternata at different stages after BR treatments by principal component analysis, in order to improve the yield and quality of P. ternata and at the same time determine the best harvest time. The results showed that the tuber yield of P. ternata was significantly increased by BR treatments at different stages (except for the 15th day). After the 15th, 45th, 60th, 75th, 90th, and 105th day of treatments, the tuber yield of P. ternata reached peak values at 0.10 (0.65 g), 0.50 (1.97 g), 0.50 (1.98 g), 1.00 (2.37 g), 1.00 (2.84 g), and 2.00 mg/L (3.76 g) BR treatment, respectively. The optimal harvest time was the 75th day after 0.10, 0.50, and 1.00 mg/L BR treatments, which not only significantly improved the yield of P. ternata, but also retained high level of total alkaloids in the tubers (20.89, 5.37, and 13.44%) and bulbils (9.74, 20.42, and 13.62%), high total flavone content in the tubers (17.66, 16.26, and 12.74%) and bulbils (52.63, 12.79, and 38.69%), and high ß-sitosterol content in the tubers (25.26, 16.65, and 0.62%) of P. ternata, compared with the control, respectively.


Assuntos
Alcaloides , Pinellia , Pinellia/química , Análise de Componente Principal , Tubérculos/química , Reguladores de Crescimento de Plantas/análise , Alcaloides/análise
11.
Int J Mol Sci ; 23(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36361895

RESUMO

Low temperatures are often used to preserve fruits and vegetables. However, low-temperature storage also causes problems, such as chilling injury, nitrite accumulation, and browning aggravation in plants. This study investigated the effects of brassinolide (BR,1.0 mg L-1) solution soaking, storage temperatures (-2 ± 0.5 °C, 4 ± 0.5 °C, and 20 ± 1 °C), and their combinations on nitrite content, color change, and quality of stored Toona sinensis bud. The results showed that low temperature (LT, 4 ± 0.5 °C) and near freezing-point temperature (NFPT, -2 ± 0.5 °C) storage effectively inhibited the decay of T. sinensis bud compared to room temperature (20 ± 1 °C, the control). The combined treatments of BR with LT or NFPT reduced nitrite content and maintained the color and the contents of vitamin C, carotenoids, saponins, ß-sitosterol, polyphenol, anthocyanin, flavonoids, and alkaloids in T. sinensis bud. BR soaking delayed the occurrence of chilling injury during NFPT storage. Meanwhile, BR soaking enhanced the DPPH radical scavenging activity, ABTS activity, and FRAP content by increasing SOD and POD activity and the contents of proline, soluble, and glutathione, thus decreasing MDA and hydrogen peroxide content and the rate of superoxide radical production in T. sinensis bud during NFPT storage. This study provides a valuable strategy for postharvest T. sinensis bud in LT and NFPT storage. BR soaking extended the shelf life during LT storage and maintained a better appearance and nutritional quality during NFPT storage.


Assuntos
Nitritos , Toona , Temperatura , Nitritos/farmacologia , Congelamento , Frutas/química
12.
Langmuir ; 37(44): 13059-13066, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34709837

RESUMO

The slab-confined water at the nanoscale exhibits anomalous dielectric properties compared to bulk water, for example, significantly low dielectric constant. In this work, we study the dielectric properties of nanoscale water droplets at room temperature using molecular dynamics simulations. We find that the nanoscale water droplets feature weakly anisotropic dielectric constant: the radial component of dielectric constants is distinctly smaller than the tangential component although they both decrease with reducing droplet size in a similar way. Such dielectric behavior is closely related to the orientational preference of water molecules near the convex surface. The molecular dipole prefers to slightly orientate toward the interior of droplets in contrast to the out-of-plane preference for free-standing water films and slab-confined water, which suppresses the fluctuation of dipole moments in the radial direction. Meanwhile, it facilitates the formation of the open hydrogen-bond network in the surface layer and ultimately leads to the relatively weak suppression of tangential fluctuations. The differential suppression is responsible for the anisotropic dielectric constant of water droplets. This anisotropic characteristic is also found in dielectric relaxation: both the radial and the tangential relaxation are consistently slowed down upon approaching surface but the latter is universally slower.

13.
Phys Chem Chem Phys ; 22(8): 4815-4822, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32068220

RESUMO

Crystallization in highly supercooled Cu50Zr50 films close to the glass transition is studied by using molecular dynamics simulations. Spontaneous nucleation is observed at the simulation timescale in contrast to the bulk counterpart. We find that nucleation occurs at free surfaces owing to the partial wetting of the nucleus by melt. The anomalous wetting phenomenon is closely related to strong density layering arising from the surface: the high density associated with surface layering increases surface energy of supercooled melts, resulting in that one facet of the crystalline embryo is preferentially formed on the film surface. The surface-based embryo is then developed into a stable nucleus by bridging two surfaces of thin films. The kinetics and thermodynamics analyses based on the mean first-passage time method show that the nucleation process still follows the description of the classical nucleation theory despite extremely high supercoolings. In nucleating, the slow interface dynamics becomes dominant and induces a low nucleation rate although the nucleation barrier is very low. The subsequent crystal growth is found to proceed in a quasi-two-dimensional manner with a ramified interface morphology, which is analogous to percolative crystals predicted in glass-forming liquids.

14.
Biochem Biophys Res Commun ; 515(1): 214-221, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31146914

RESUMO

Small cell lung carcinoma (SCLC) is one of the deadliest cancer types, with a 5-year survival rate less than 10%. Kdm1a/Lsd1 has recently been implicated as a potential therapeutic target for SCLC. However, the underlying molecular mechanism by which Kdm1a promotes the oncogenesis of SCLC has not been fully understood. Kdm1a is significantly elevated in most human SCLC specimens, whereas Rest, a tumor suppressor and neuronal repressive transcriptional factor, is typically inactivated. Knock-out of Kdm1a (Kdm1a-KO) in mouse SCLC cell lines resulted in the suppression of cell growth and soft agar colony formation. RNA-Seq analysis of the Kdm1a-KO cells revealed significant repression of a program of neuroendocrine signature genes, and conversely, a significant upregulation of a network of genes capable of inhibiting tumor cell growth. Rest was identified among the top 10 upregulated genes in Kdm1a-KO cells. The treatment of the SCLC cells with Kdm1a demethylase inhibitors resulted in a dramatic up-regulation of Rest similar to the extent of that in Kdm1a-KO cells. Importantly, accompanying the restored expression of the SCLC signature genes, knock-out of Rest in Kdm1a-KO cells rescued the restricted cell growth and soft agar colony formation. Taken together, these novel findings show that Kdm1a is a key transcriptional repressor of Rest, and that suppression of SCLC progression by the targeted inhibition of Kdm1a depends on the reactivation of Rest, suggesting a new strategy for effective SCLC treatment by targeting the Kdm1a/Rest molecular pathway.


Assuntos
Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Histona Desmetilases/genética , Neoplasias Pulmonares/genética , Proteínas Repressoras/genética , Carcinoma de Pequenas Células do Pulmão/genética , Animais , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Estudos de Coortes , Progressão da Doença , Células HEK293 , Histona Desmetilases/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos Knockout , Proteínas Repressoras/metabolismo , Carcinoma de Pequenas Células do Pulmão/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia
15.
Biotechnol Appl Biochem ; 64(2): 153-164, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26790544

RESUMO

NS3 protease plays a vital role in the replication of the hepatitis C virus (HCV). BMS-605339 is a novel linear tetra-peptide α-ketoamide inhibitor of NS3 protease and shows specificity for HCV NS3 protease genotype 1a and genotype 1b. Mutation at the key site 168 of the HCV NS3 protease can induce resistance to BMS-605339, which greatly affects the antiviral therapy efficacy to hepatitis C. In the present study, we employed molecular dynamics simulations, free energy calculations, and free energy decomposition to explore the drug resistance mechanism of BMS-605339 due to the three representative mutations D168C/Y/V. The free energy decomposition analysis indicates that the decrease in the binding affinity is mainly attributed to the decrease in both van der Waals and electrostatic interactions. After detailed analysis of our calculated results, we observed that the break of the salt bridge between residues 155 and 168 caused by the mutations D168C/Y/V is the original reason for the decrease in the binding ability between BMS-605339 and the mutant NS3 proteases. The obtained results will reveal the drug resistance mechanism between BMS-605339 and the mutant NS3 proteases, and provide valuable clue for designing novel and more potent drugs to HCV NS3 protease.


Assuntos
Resistência a Medicamentos/genética , Hepatite C/tratamento farmacológico , Inibidores de Proteases/química , Proteínas não Estruturais Virais/genética , Antivirais/química , Antivirais/uso terapêutico , Biologia Computacional , Hepacivirus/efeitos dos fármacos , Hepacivirus/patogenicidade , Hepatite C/virologia , Humanos , Isoquinolinas/química , Isoquinolinas/uso terapêutico , Simulação de Dinâmica Molecular , Mutação , Inibidores de Proteases/uso terapêutico , Sulfonamidas/química , Sulfonamidas/uso terapêutico , Proteínas não Estruturais Virais/química
16.
Biochem Cell Biol ; 94(2): 147-58, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26836778

RESUMO

NS5B polymerase plays an important role in viral replication machinery. TMC647055 (TMC) is a novel and potent non-nucleoside inhibitor of the HCV NS5B polymerase. However, mutations that result in drug resistance to TMC have been reported. In this study, we used molecular dynamics (MD) simulations, binding free energy calculations, and free energy decomposition to investigate the drug resistance mechanism of HCV to TMC resulting from L392I, P495T, P495S, and P495L mutations in NS5B polymerase. From the calculated results we determined that the decrease in the binding affinity between TMC and NS5B(L392I) polymerase is mainly caused by the extra methyl group at the CB atom of Ile. The polarity of the side-chain of residue 495 has no distinct influence on residue 495 binding with TMC, whereas the smaller size of the side-chain of residue 495 causes a substantial decrease in the van der Walls interaction between TMC and residue 495. Moreover, the longer length of the side-chain of residue 495 has a significant effect on the electrostatic interaction between TMC and Arg-503. Finally, we performed the same calculations and detailed analysis on other 3 mutations (L392V, P495V, and P495I). The results further confirmed our conclusions. The computational results not only reveal the drug resistance mechanism between TMC647055 and NS5B polymerase, but also provide valuable information for the rational design of more potent non-nucleoside inhibitors targeting HCV NS5B polymerase.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Sulfonamidas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Modelos Moleculares , Mutação , Relação Estrutura-Atividade , Sulfonamidas/química , Termodinâmica , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo
17.
Int J Cancer ; 134(10): 2294-304, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24174333

RESUMO

Metastasis is the major cause for high mortality of lung cancer with the underlying mechanisms poorly understood. The scaffolding protein neural precursor cell expressed, developmentally down-regulated 9 (NEDD9) has been identified as a pro-metastasis gene in several types of cancers including melanoma and breast cancer. However, the exact role and related mechanism of NEDD9 in regulating lung cancer metastasis still remain largely unknown. Here, we demonstrate that NEDD9 knockdown significantly inhibits migration, invasion and metastasis of lung cancer cells in vitro and in vivo. The pro-metastasis role of Nedd9 in lung cancer is further supported by studies in mice models of spontaneous cancer metastasis. Moreover, we find that NEDD9 promotes lung cancer cell migration and invasion through the induction of epithelial-mesenchymal transition (EMT) potentially via focal adhesion kinase activation. More importantly, NEDD9 expression inversely correlates with E-cadherin expression in human lung cancer specimens, consistent with the findings from in vitro studies. Taken together, this study highlights that NEDD9 is an important mediator promotes lung cancer metastasis via EMT.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Transição Epitelial-Mesenquimal/genética , Neoplasias Pulmonares/genética , Fosfoproteínas/genética , Transcriptoma , Proteínas Quinases Ativadas por AMP , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Western Blotting , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proteína-Tirosina Quinases de Adesão Focal/genética , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Knockout , Camundongos Nus , Camundongos Transgênicos , Metástase Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Pharm Res ; 31(11): 3051-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24805280

RESUMO

PURPOSE: The acne skin is characteristic of a relatively lower pH microenvironment compared to the healthy skin. The aim of this work was to utilize such pH discrepancy as a site-specific trigger for on-demand topical adapalene delivery. METHODS: The anti-acne agent, adapalene, was encapsulated in acid-responsive polymer (Eudragit® EPO) nanocarriers via nanoprecipitation. The nanocarriers were characterized in terms of particle size, surface morphology, drug-carrier interaction, drug release and permeation. RESULTS: Adapalene experienced a rapid release at pH 4.0 in contrast to that at pH 5.0 and 6.0. The permeation study using silicone membrane revealed a significant higher drug flux from the nanocarrier (6.5 ± 0.6 µg.cm(-2).h(-1)) in comparison to that (3.9 ± 0.4 µg.cm(-2).h(-1)) in the control vehicle (Transcutol®). The in vitro pig skin tape stripping study showed that at 24 h post dose-application the nanocarrier delivered the same amount of drug to the stratum corneum as the positive control vehicle did. CONCLUSIONS: The acid-responsive nanocarriers hold promise for efficient adapalene delivery and thus improved acne therapy.


Assuntos
Ácidos/química , Portadores de Fármacos/química , Nanopartículas/química , Naftalenos/administração & dosagem , Naftalenos/química , Polímeros/química , Acne Vulgar/tratamento farmacológico , Adapaleno , Administração Cutânea , Animais , Portadores de Fármacos/administração & dosagem , Sistemas de Liberação de Medicamentos , Concentração de Íons de Hidrogênio , Nanopartículas/administração & dosagem , Polímeros/administração & dosagem , Pele/efeitos dos fármacos , Absorção Cutânea , Suínos
19.
Sci Rep ; 14(1): 5894, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467703

RESUMO

Global climate change associated with increased carbon emissions has become a global concern. Resource-based cities, by estimations, have emerged as major contributors to carbon emissions, accounting for approximately one-third of the national total. This underscores their pivotal role in the pursuit of carbon neutrality goals. Despite this, resource-based cities have long been neglected in current climate change mitigation policy discussions. Accordingly, using exploratory spatial data analysis and Geographical Weighted Regression method, this study investigates the determinants of carbon emissions and their spatial pattern in 113 resource-based cities in China. It can be concluded that: (1) The proportion of carbon emissions from resource-based cities in the national total has shown a marginal increase between 2003 and 2017, and the emissions from these cities have not yet reached their peak. (2) A relatively stable spatial pattern of "northeast high, southwest low" characterizes carbon emissions in resource-based cities, displaying significant spatial autocorrelation. (3) Population size, economic development level, carbon abatement technology, and the proportion of resource-based industries all contribute to the increase in carbon emissions in these cities, with carbon abatement technology playing a predominant role. (4) There is a spatial variation in the strength of the effects of the various influences.

20.
Sci Rep ; 14(1): 14219, 2024 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902308

RESUMO

A network meta-analysis of randomized controlled trials was conducted to compare and rank the effectiveness of various noninvasive brain stimulation (NIBS) for Parkinson's disease (PD). We searched PubMed, Web of Science, Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), Wanfang Database, China Science and Technology Journal Database (VIP), and Chinese Biomedical Literature Service System (SinoMed) databases from the date of database inception to April 30th, 2024. Two researchers independently screened studies of NIBS treatment in patients with PD based on inclusion and exclusion criteria. Two researchers independently performed data extraction of the included studies using an Excel spreadsheet and assessed the quality of the literature according to the Cochrane Risk of Bias Assessment Tool (RoB2). Network meta-analysis was performed in StataMP 17.0. A total of 28 studies involving 1628 PD patients were included. The results showed that HF-rTMS over the SMA (SMD = - 2.01; 95% CI [- 2.87, - 1.15]), HF-rTMS over the M1 and DLPFC (SMD = - 1.80; 95% CI [- 2.90, - 0.70]), HF-rTMS over the M1 (SMD = - 1.10; 95% CI [- 1.55, - 0.65]), a-tDCS over the DLPFC (SMD = - 1.08; 95% CI [- 1.90, - 0.27]), HF-rTMS over the M1 and PFC (SMD = - 0.92; 95% CI [- 1.71, - 0.14]), LF-rTMS over the M1 (SMD = - 0.72; 95% CI [- 1.17, - 0.28]), and HF-rTMS over the DLPFC (SMD = - 0.70; 95% CI [- 1.21, - 0.19]) were significantly improved motor function compared with sham stimulation. The SUCRA three highest ranked were HF-rTMS over the SMA (95.1%), HF-rTMS over the M1 and DLPFC (89.6%), and HF-rTMS over the M1 (73.0%). In terms of enhanced cognitive function, HF-rTMS over the DLPFC (SMD = 0.80; 95% CI [0.03,1.56]) was significantly better than sham stimulation. The SUCRA three most highly ranked were a-tDCS over the M1 (69.8%), c-tDCS over the DLPFC (66.9%), and iTBS over the DLPFC (65.3%). HF-rTMS over the M1 (SMD = - 1.43; 95% CI [- 2.26, - 0.61]) and HF-rTMS over the DLPFC (SMD = - 0.79; 95% CI [- 1.45, - 0.12)]) significantly improved depression. The SUCRA three highest ranked were HF-rTMS over the M1 (94.1%), LF-rTMS over the M1 (71.8%), and HF-rTMS over the DLPFC (69.0%). HF-rTMS over the SMA may be the best option for improving motor symptoms in PD patients. a-tDCS and HF-rTMS over the M1 may be the NIBS with the most significant effects on cognition and depression, separately.Trial registration: International Prospective Register of Systematic Review, PROSPERO (CRD42023456088).


Assuntos
Metanálise em Rede , Doença de Parkinson , Doença de Parkinson/terapia , Doença de Parkinson/fisiopatologia , Humanos , Estimulação Magnética Transcraniana/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
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