Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
J Mol Model ; 30(9): 298, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39103652

RESUMO

CONTEXT: This study explores the interaction between particles in microplastic semi-coke water slurry at the molecular level using molecular simulation methods, specifically DFT calculations and MD simulations. In addition, the experiment of slurry preparation was carried out to study the viscosity and stability of the slurry. The electrostatic potential analysis shows that the interaction between microplastics and dispersant molecules occurs on atoms with large electronegativity or oxygen-containing functional groups, and the energy gap of frontier molecular orbitals indicated that PVC interacts most easily with the dispersant (0.39 eV), followed by PS (1.08 eV) and PET (3.65 eV). In addition, it is also noted that due to the steric hindrance effect, the adsorption energy was opposite to the DFT calculation results: PET was - 213.338 kcal/mol (NNO) which was highest, followed by PS (- 107.603 kcal/mol, NNO), and PVC (NNO) was lowest which was - 94.808 kcal/mol. And RDF shows similar results, which the probability of water molecules in the PET system was the highest, followed by PS, and finally, PVC. The MD results are consistent with the viscosity and stability characterization results of the slurry which PET has the lowest viscosity of 87.3 mPa·s. Finally, this study provides new ideas for the treatment of microplastics and the improvement of the performance of semi-coke water slurry and reveals the interaction mechanism between microplastics and semi-coke water slurry. METHODS: All calculations were performed using Materials Studio (MS) version 2020 software, BIOVIA Corporation. The DFT calculation was carried out through the DMol3 module. The DFT calculations include electron density, electrostatics, orbitals, and population analysis. In DMol3 module, the GGA-PBE function was selected to consider gradient changes in density in the simulated calculation. The DFT-D correction was selected, and all electrons were calculated by DNP for accurate core potentials and the DNP file was 4.4. MD simulation was performed through the Forcite module. MD simulation mainly focuses on relative concentration distribution analysis, radial distribution function, and adsorption energy calculation. All molecular geometry optimizations are performed in the Forcite module. In the molecular dynamic part, all simulations used PCFF forcefield. The NVT ensemble was adopted and using the Nosé thermostat.

2.
Heliyon ; 10(8): e29515, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38638982

RESUMO

Of all malignancies, pancreatic ductal adenocarcinoma (PDAC), constituting 90% of pancreatic cancers, has the worst prognosis. Glycolysis is overactive in PDAC patients and is associated with poor prognosis. Drugs that inhibit glycolysis as well as induce cell death need to be identified. However, glycolysis inhibitors often fail to induce cell death. We here found that FV-429, a derivative of the natural flavonoid wogonin, can induce mitochondrial apoptosis and inhibit glycolysis in PDAC in vivo and in vitro. In vitro, FV-429 inhibited intracellular ATP content, glucose uptake, and lactate generation, consequently leading to mitochondrial dysfunction and apoptosis in PDAC cells. Furthermore, it decreased the expression of PKM2 (a specific form of pyruvate kinase) through the ERK signaling pathway and enhanced PKM2 nuclear translocation. TEPP-46, the activator of PKM2, reversed FV-429-induced glycolysis inhibition and mitochondrial apoptosis in the PDAC cells. In addition, FV-429 exhibited significant tumor suppressor activity and high safety in BxPC-3 cell xenotransplantation models. These results thus demonstrated that FV-429 decreases PKM2 expression through the ERK signaling pathway and enhances PKM2 nuclear translocation, thereby resulting in glycolysis inhibition and mitochondrial apoptosis in PDAC in vitro and in vivo, which makes FV-429 a promising candidate for pancreatic cancer treatment.

3.
iScience ; 27(3): 109246, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439974

RESUMO

Prostate cancer (PCa) is a serious health concern for men due to its high incidence and mortality rate. The first therapy typically adopted is androgen deprivation therapy (ADT). However, patient response to ADT varies, and 20-30% of PCa cases develop into castration-resistant prostate cancer (CRPC). This article investigates the anti-PCa effect of a drug candidate named GL-V9 and highlights the significant mechanism involving the AKT-hexokinase II (HKII) pathway. In both androgen receptor (AR)-expressing 22RV1 cells and AR-negative PC3 cells, GL-V9 suppressed phosphorylated AKT and mitochondrial location of HKII. This led to glycolytic inhibition and mitochondrial pathway-mediated apoptosis. Additionally, GL-V9 inhibited AR activity in 22RV1 cells and disrupted the feedback activation of AKT signaling in condition of AR inhibition. This disruption greatly increased the anti-PCa efficacy of the AR antagonist bicalutamide. In conclusion, we present a novel anti-PCa candidate and combination drug strategies to combat CRPC by intervening in the AR-AKT-HKII signaling network.

4.
Food Chem Toxicol ; 169: 113450, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36208653

RESUMO

Prostate cancer (PCa) cells exploit cellular metabolic reprogramming as their survival advantage, especially aberrant lipid signaling and metabolism. Although recent studies deemed that PCa tends to rely on lipid fuel in comparison with aerobic glycolysis, the relationship between lipid metabolism and cancer growth remains unknown. We demonstrated that wogonin, a naturally occurring mono-flavonoid, could induce apoptosis of PCa cells in vivo and in vitro. Mechanistically, 100 µM wogonin significantly increased the expression of proteins related to the fatty acid synthesis and accumulation as a result of stimulation of AKT phosphorylation and nuclear accumulation of sterol regulatory element-binding protein 1 (SREBP1). The wogonin-induced up-regulation of fatty acid synthase (FASN) promoted fatty acid synthesis and storage, while increased oxidation in mitochondria driven by carnitine palmitoyl-transferase 1A (CPT1A) resulted in the loss of mitochondrial membrane potential and reactive oxygen species (ROS) accumulation, ultimately inducing apoptosis in DU145 and 22Rv1 cells. In vivo, 100 mg/kg of wogonin (i.v.) significantly repressed tumor growth without any obvious toxicity in the PCa xenograft model. In short, we proved that wogonin regulated the fatty acid metabolism and induced apoptosis by activating the AKT-SREBP1-FASN signaling network in human PCa cells, and it exhibited potent anti-tumor effects both in vivo and vitro. Thus it might be a promising candidate for the development of anti-cancer drugs.


Assuntos
Antineoplásicos , Apoptose , Ácido Graxo Sintase Tipo I , Ácidos Graxos , Flavanonas , Neoplasias da Próstata , Proteína de Ligação a Elemento Regulador de Esterol 1 , Humanos , Masculino , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ácido Graxo Sintase Tipo I/metabolismo , Ácidos Graxos/metabolismo , Flavanonas/farmacologia , Metabolismo dos Lipídeos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Carnitina O-Acetiltransferase/metabolismo
5.
ACS Appl Mater Interfaces ; 13(47): 56530-56543, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34758621

RESUMO

Gas barrier membranes with impressive moisture permeability are highly demanded in air or nature gas dehumidification. We report a novel approach using polyetheramine oligomers covalently grafted on the carbon nanotubes (CNTs) to engineer liquid-like CNT nanofluids (CNT NFs), which are incorporated into a polyimide matrix to enhance the gas barrier and moisture permeation properties. Benefiting from the featured liquid-like characteristic of CNT NFs, a strong interfacial compatibility between CNTs and the polyimide matrix is achieved, and thus, the resulting membranes exhibit high heat resistance and desirable mechanical strength as well as remarkable fracture toughness, beneficially to withstanding creep, impact, and stress fatigue in separation applications. Positron annihilation lifetime spectroscopy measurements indicate a significant decrease in fractional free volume within the resulting membranes, leading to greatly enhanced gas barrier properties while almost showing full retention of moisture permeability compared to that of the pristine membrane. For membranes with 10 wt % CNT NFs, the gas transmission rates, respectively, decrease 99.9% for CH4, 94.4% for CO2, 99.2% for N2, and 97.9% for O2 compared with that of the pristine membrane. Most importantly, with the increasing amount of CNT NFs, the hybrid membranes demonstrate a simultaneous increase of barrier performance and permselectivity for H2O/CH4, H2O/N2, H2O/CO2, and H2O/O2. All these results make these membranes potential candidates for high-pressure natural gas or hyperthermal air dehydration.

6.
J Antimicrob Chemother ; 76(7): 1898-1906, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-33792714

RESUMO

OBJECTIVES: With the goal of facilitating the use of HIV-TRePS to optimize therapy in settings with limited healthcare resources, we aimed to develop computational models to predict treatment responses accurately in the absence of commonly used baseline data. METHODS: Twelve sets of random forest models were trained using very large, global datasets to predict either the probability of virological response (classifier models) or the absolute change in viral load in response to a new regimen (absolute models) following virological failure. Two 'standard' models were developed with all baseline variables present and 10 others developed without HIV genotype, time on therapy, CD4 count or any combination of the above. RESULTS: The standard classifier models achieved an AUC of 0.89 in cross-validation and independent testing. Models with missing variables achieved AUC values of 0.78-0.90. The standard absolute models made predictions that correlated significantly with observed changes in viral load with a mean absolute error of 0.65 log10 copies HIV RNA/mL in cross-validation and 0.69 log10 copies HIV RNA/mL in independent testing. Models with missing variables achieved values of 0.65-0.75 log10 copies HIV RNA/mL. All models identified alternative regimens that were predicted to be effective for the vast majority of cases where the new regimen prescribed in the clinic failed. All models were significantly better predictors of treatment response than genotyping with rules-based interpretation. CONCLUSIONS: These latest models that predict treatment responses accurately, even when a number of baseline variables are not available, are a major advance with greatly enhanced potential benefit, particularly in resource-limited settings. The only obstacle to realizing this potential is the willingness of healthcare professions to use the system.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Atenção à Saúde , Genótipo , HIV/genética , Infecções por HIV/tratamento farmacológico , Humanos , RNA Viral , Carga Viral
7.
BMC Pregnancy Childbirth ; 19(1): 502, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842804

RESUMO

BACKGROUND: The aim of this study was to assess the feasibility, safety and outcome of the embolization of non-gonadal collateral supplying gestational sac (GS) in addition to uterine artery embolization (UAE), followed by hysteroscopic curettage for the management of cesarean scar pregnancy (CSP). METHODS: A retrospective study was undertaken from January 2012 to September 2018 in 24 CSP patients in whom non-gonadal collaterals supplying GS were identified by arterial angiography performed immediately after UAE. These patients underwent attempt collateral embolization in addition to UAE, followed by hysteroscopic curettage for the management of CSP. The 24 patients were divided into two groups based on whether they underwent technically successful collateral embolization (UAE-SCE group) or failed collateral embolization (UAE-FCE group) in addition to UAE. The baseline characteristics and clinical outcomes including time for serum ß-human chorionic gonadotropin (ß-hCG) levels normalization, blood loss, secondary anemia, and pelvic pain were compared between the two groups. The paired t test and Man Whitney test were used for comparisons of discrete and numerical variables, respectively. RESULTS: Collateral embolization was techinically successful in 16 (66.7%, 16/24) patients and failed in the other 8 (33.3%, 8/24) patients. There were no significant differences between the two groups in baseline characteristics. The mean blood loss and secondary anemia in the UAE-SCE group were significantly less than UAE-FCE group. No significant difference was found between the two groups in the mean time for ß-hCG levels normalization and pelvic pain. CONCLUSIONS: During the management of UAE combined with hysteroscopic curettage for CSP, additional embolization of non-gonadal collateral supplying GS during UAE is feasible and safe in patients with non-gonadal collateral supplying GS, and the additional embolization of the collateral may reduce blood bloss related to hysteroscopic curettage.


Assuntos
Curetagem/métodos , Saco Gestacional/irrigação sanguínea , Histeroscopia/métodos , Gravidez Ectópica/cirurgia , Embolização da Artéria Uterina/métodos , Adulto , Cesárea/efeitos adversos , Cicatriz/complicações , Circulação Colateral , Terapia Combinada , Estudos de Viabilidade , Feminino , Humanos , Gravidez , Gravidez Ectópica/etiologia , Estudos Retrospectivos , Resultado do Tratamento
8.
J Acquir Immune Defic Syndr ; 81(2): 207-215, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30865186

RESUMO

OBJECTIVE: Definitions of virological response vary from <50 up to 1000 copies of HIV-RNA/mL. Our previous models estimate the probability of HIV drug combinations reducing the viral load to <50 copies/mL, with no indication of whether higher thresholds of response may be achieved. Here, we describe the development of models that predict absolute viral load over time. METHODS: Two sets of random forest models were developed using 50,270 treatment change episodes from more than 20 countries. The models estimated viral load at different time points following the introduction of a new regimen from variables including baseline viral load, CD4 count, and treatment history. One set also used genotypes in their predictions. Independent data sets were used for evaluation. RESULTS: Both models achieved highly significant correlations between predicted and actual viral load changes (r = 0.67-0.68, mean absolute error of 0.73-0.74 log10 copies/mL). The models produced curves of virological response over time. Using failure definitions of <100, 400, or 1000 copies/mL, but not 50 copies/mL, both models were able to identify alternative regimens they predicted to be effective for the majority of cases where the new regimen prescribed in the clinic failed. CONCLUSIONS: These models could be useful for selecting the optimum combination therapy for patients requiring a change in therapy in settings using any definition of virological response. They also give an idea of the likely response curve over time. Given that genotypes are not required, these models could be a useful addition to the HIV-TRePS system for those in resource-limited settings.


Assuntos
Antirretrovirais/farmacologia , HIV/efeitos dos fármacos , Carga Viral/efeitos dos fármacos , Adulto , Antirretrovirais/uso terapêutico , Contagem de Linfócito CD4 , Quimioterapia Combinada , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Masculino , Modelos Estatísticos , RNA Viral/sangue
9.
J Antimicrob Chemother ; 69(4): 1104-10, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24275116

RESUMO

OBJECTIVES: The optimal individualized selection of antiretroviral drugs in resource-limited settings is challenging because of the limited availability of drugs and genotyping. Here we describe the development of the latest computational models to predict the response to combination antiretroviral therapy without a genotype, for potential use in such settings. METHODS: Random forest models were trained to predict the probability of a virological response to therapy (<50 copies HIV RNA/mL) following virological failure using the following data from 22,567 treatment-change episodes including 1090 from southern Africa: baseline viral load and CD4 cell count, treatment history, drugs in the new regimen, time to follow-up and follow-up viral load. The models were assessed during cross-validation and with an independent global test set of 1000 cases including 100 from southern Africa. The models' accuracy [area under the receiver-operating characteristic curve (AUC)] was evaluated and compared with genotyping using rules-based interpretation systems for those cases with genotypes available. RESULTS: The models achieved AUCs of 0.79-0.84 (mean 0.82) during cross-validation, 0.80 with the global test set and 0.78 with the southern African subset. The AUCs were significantly lower (0.56-0.57) for genotyping. CONCLUSIONS: The models predicted virological response to HIV therapy without a genotype as accurately as previous models that included a genotype. They were accurate for cases from southern Africa and significantly more accurate than genotyping. These models will be accessible via the online treatment support tool HIV-TRePS and have the potential to help optimize antiretroviral therapy in resource-limited settings where genotyping is not generally available.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Simulação por Computador , Infecções por HIV/tratamento farmacológico , HIV/efeitos dos fármacos , HIV/genética , Terapia de Salvação/métodos , Adulto , Feminino , Genótipo , Infecções por HIV/virologia , Humanos , Masculino , Prognóstico , Resultado do Tratamento
11.
Nicotine Tob Res ; 11(5): 475-80, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19346506

RESUMO

INTRODUCTION: A Society for Research on Nicotine and Tobacco working group recommended outcome measures for cessation-induction trials and aid-to-cessation trials. Cessation-induction trials aim to motivate unwilling quitters to make a quit attempt. Aid-to-cessation trials give either medication or behavioral interventions to increase the rate at which willing quitters succeed in their attempts. Nicotine-assisted reduction programs combine features of both types of interventions by giving nicotine replacement to unwilling quitters. Treatment can be prolonged more than a year, quit attempts can occur and succeed early or late in the program, and renewed quit attempts are an inherent part of the program. Conventional outcome measures are tied to a fixed but arbitrary point in follow-up and cannot capture the true outcome: Prolonged cessation anchored to the point at which a person makes a successful quit attempt. DISCUSSION: We propose that the outcome should be counted from the successful quit attempt that began during the treatment period and continues for a defined period, ideally 6 months. In particular, if a trial compared a short reduction program with a long reduction program, it would not be possible to obtain an unbiased assessment of the outcome of such a trial using a measure tied to a fixed point in follow-up. Floating prolonged abstinence could provide such an assessment and is suitable for either prolonged cessation-induction trial or combined cessation-induction and aid-to-cessation trials.


Assuntos
Avaliação de Resultados em Cuidados de Saúde/normas , Abandono do Hábito de Fumar/métodos , Prevenção do Hábito de Fumar , Síndrome de Abstinência a Substâncias , Humanos , Motivação , Nicotina/administração & dosagem , Abandono do Hábito de Fumar/psicologia , Fatores de Tempo
12.
BMJ ; 338: b1024, 2009 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-19342408

RESUMO

OBJECTIVE: To determine the effectiveness and safety of nicotine replacement therapy assisted reduction to stop smoking. DESIGN: Systematic review of randomised controlled trials. DATA SOURCES: Cochrane Library, Medline, Embase, CINAHL, PsychINFO, Science Citation Index, registries of ongoing trials, reference lists, the drug company that sponsored most of the trials, and clinical experts. Review methods Eligible studies were published or unpublished randomised controlled trials that enrolled smokers who declared no intention to quit smoking in the short term, and compared nicotine replacement therapy (with or without motivational support) with placebo, no treatment, other pharmacological therapy, or motivational support, and reported quit rates. Two reviewers independently applied eligibility criteria. One reviewer assessed study quality and extracted data and these processes were checked by a second reviewer. The primary outcome, six months sustained abstinence from smoking beginning during treatment, was assessed by individual patient data analysis. Other outcomes were cessation and reduction at end of follow-up, and adverse events. DATA SYNTHESIS: Seven placebo controlled randomised controlled trials were included (four used nicotine replacement therapy gum, two nicotine replacement therapy inhaler, and one free choice of therapy). They were reduction studies that reported smoking cessation as a secondary outcome. The trials enrolled a total of 2767 smokers, gave nicotine replacement therapy for 6-18 months, and lasted 12-26 months. 6.75% of smokers receiving nicotine replacement therapy attained sustained abstinence for six months, twice the rate of those receiving placebo (relative risk (fixed effects) 2.06, 95% confidence interval 1.34 to 3.15; (random effects) 1.99, 1.01 to 3.91; five trials). The number needed to treat was 29. All other cessation and reduction outcomes were significantly more likely in smokers given nicotine replacement therapy than those given placebo. There were no statistically significant differences in adverse events (death, odds ratio 1.00, 95% confidence interval 0.25 to 4.02; serious adverse events, 1.16, 0.79 to 1.50; and discontinuation because of adverse events, 1.25, 0.64 to 2.51) except nausea, which was more common with nicotine replacement therapy (8.7% v 5.3%; odds ratio 1.69, 95% confidence interval 1.21 to 2.36). CONCLUSIONS: Available trials indicate that nicotine replacement therapy is an effective intervention in achieving sustained smoking abstinence for smokers who have no intention or are unable to attempt an abrupt quit. Most of the evidence, however, comes from trials with regular behavioural support and monitoring and it is unclear whether using nicotine replacement therapy without regular contact would be as effective.


Assuntos
Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Abandono do Hábito de Fumar/métodos , Terapia Comportamental/métodos , Terapia Combinada , Feminino , Humanos , Masculino , Nicotina/efeitos adversos , Agonistas Nicotínicos/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA