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Increasing the levels of antiapoptotic Bcl-2 proteins is an important way that cancer cells utilize to get out of apoptosis, underscoring their significance as promising targets for anticancer therapies. Lately, a primary compound 1 bearing thiazolidine-2,4-dione was discovered to exhibit comparable Mcl-1 inhibitory activity in comparison to WL-276. Herein, thirty-nine thiazolidine-2,4-dione analogs were yielded through incorporating different biphenyl moieties (R1), amino acid side chains (R2) and sulfonamides (R3) on 1. The findings indicated that certain compounds exhibited favorable inhibitory effects against Bcl-2/Mcl-1, while demonstrating limited or negligible binding affinity towards Bcl-xL. In particular, compounds 16 and 20 exhibited greater Bcl-2/Mcl-1 inhibition compared to AT-101, WL-276 and 1. Moreover, they demonstrated notable antiproliferative effects and significantly induced apoptosis in U937 cells. The western blot and co-immunoprecipitation assays confirmed that 20 could induce alterations in the expression of apoptosis-associated proteins to result in apoptosis through on-target Bcl-2 and Mcl-1 inhibition. In addition, 20 exhibited favorable stability profiles in both rat plasma and rat liver microsomes. In total, 20 could be used as a promising compound to discover Bcl-2/Mcl-1 dual inhibitors with favorable therapeutic properties.
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OBJECTIVE: This study aims to investigate the relationship between abnormal vaginal microecology and human papillomavirus (HPV) infection, as well as the squamous intraepithelial lesions (SIL) progression. METHODS: A total of 383 patients diagnosed with HPV infection in our hospital between March 2017 and February 2022 were selected as the experimental group. In addition, several volunteers (n = 898) who underwent physical examination during the same period were randomly selected as the control group. Subsequently, we conducted several investigations, such as HPV detection and gene typing, examined vaginal microecological imbalances, and performed cytological examinations to analyze the correlation between microecological changes, different types of HPV infection, and SIL progression. RESULTS: HPV detection primarily included single and high-risk types of HPV infections. Moreover, significant disparities in the vaginal microecological environment between patients with persistent HPV infection and the control group, as well as patients with low-grade and high-grade SIL (LSIL and HSIL), were observed. The regression analysis revealed a correlation between LSIL and microflora density, diversity, bacteriological vaginosis (BV), vulvovaginal candidiasis (VVC), trichomonas vaginalis (TV), sialidase, as well as Lactobacillus. In addition, we identified an association between HSIL and pH, flora density, diversity, BV, VVC, candida vaginitis (CV), leukocyte esterase, catalase, and Lactobacillus levels. CONCLUSION: These findings revealed a significant association between abnormal vaginal microecology and both HPV infection and the SIL progression.
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Candidíase Vulvovaginal , Infecções por Papillomavirus , Lesões Intraepiteliais Escamosas , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Infecções por Papillomavirus/diagnóstico , Esfregaço Vaginal , Vagina/patologia , Papillomaviridae/genética , Displasia do Colo do Útero/diagnósticoRESUMO
In recent years, significant advancements have been made in the research of photoswitchable probes. These probes undergo reversible structural and electronic changes upon light exposure, thus exhibiting vast potential in molecular detection, biological imaging, material science, and information storage. Through precisely engineered molecular structures, the photoswitchable probes can toggle between "on" and "off" states at specific wavelengths, enabling highly sensitive and selective detection of targeted analytes. This review systematically presents photoswitchable fluorescent and colorimetric probes built on various molecular photoswitches, primarily focusing on the types involving photoswitching in their detection and/or signal response processes. It begins with an analysis of various molecular photoswitches, including their photophysical properties, photoisomerization and photochromic mechanisms, and fundamental design concepts for constructing photoswitchable probes. The article then elaborates on the applications of these probes in detecting diverse targets, including cations, anions, small molecules, and biomacromolecules. Finally, it offers perspectives on the current state and future development of photoswitchable probes. This review aims to provide a clear introduction for researchers in the field and guidance for the design and application of new, efficient fluorescent and colorimetric probes.
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The association between admission heart rate (HR) and the mortality of critically ill patients with acute aortic dissection (AAD) remains unclear.The data were extracted from the Medical Information Mart for Intensive Care (MIMIC-III) database. Cox regression models and Kaplan-Meier (KM) survival curve were used to explore the association between admission HR and 90-day, 1-year, and 3-year mortality in patients with AAD. Sensitivity analyses were conducted to assess potential bias.A total of 374 eligible AAD patients were included and divided in 4 groups according to admission HR (HR ≤ 70, 71-80, 81-90, and > 90 beats per minute (bpm) ). The patients with AAD in the group with HR > 90 bpm had higher 90-day, 1-year, and 3-year mortality than those in the groups with HR ≤ 70, 71-80, and 81-90 bpm. After adjusting for age, sex, BMI, systolic blood pressure, diastolic blood pressure, SOFA score, SAPSII score, Stanford type, hypertension, coronary artery disease, liver disease, atrial fibrillation, valvular disease, intensive care unit mechanical ventilation, aortic surgery, and thoracic endovascular aortic repair, patients with admission HR > 90 bpm had a higher risk of 90-day, 1-year, and 3-year mortality [adjusted hazard ratio, 95% confidence interval, 5.14 (2.22-11.91) P < 0.001; 4.31 (2.10-8.84) P < 0.001; 3.01 (1.66-5.46) P < 0.001] than those with HR 81-90 bpm. The 90-day, 1-year, and 3-year mortality were similar among the groups with HR ≤ 70, 71-80, and 81-90 bpm.Admission HR > 90 bpm was independently associated with all-cause mortality in critically ill AAD patients, either type A or B aortic dissection.
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Dissecção Aórtica , Hipertensão , Humanos , Frequência Cardíaca , Estado Terminal , Unidades de Terapia Intensiva , Estudos RetrospectivosRESUMO
BACKGROUND: Deoxynivalenol (DON) produced during the onset of fusarium head blight not only affects the quality and safety of wheat but also causes serious harm to human and livestock health. However, due to the high stability of DON, it is difficult to eliminate it or reduce it naturally after it has been produced. Cold plasma technology is a non-thermophysical processing technology that has been widely used for microbial inactivation and mycotoxin degradation. In this study, the degradation efficiency of double dielectric barrier discharge (DDBD) cold plasma on DON in aqueous solution and wheat was studied; the structures of degradation products of DON and its pathway were clarified, and the effect of DDBD plasma on wheat quality was evaluated. RESULTS: Double dielectric barrier discharge cold plasma was used for efficient degradation of DON (0.5 ~ 5 µgmL^-1) solution and achieved a degradation rate of 98.94% within 25 min under the optimal conditions (voltage 100 V, frequency 200 Hz, duty cycle 80%). Furthermore, 10 degradation products (C15 H24 O5 , C15 H22 O6 , C15 H22 O9 , C16 H22 O7 , C15 H20 O7 , C15 H20 O9 , C15 H18 O8 , C15 H22 O5 , C16 H24 O5 , and C15 H18 O9 ) were identified by ultra-performance liquid chromatography-time of flight-mass spectrometry (UPLC-TOF-MS/MS) combined with Metabolitepilot and Peakview software. The degradation pathway of DON was obtained based on the chemical structures and accurate mass of these products. The DON degradation rate of 61% in wheat was achieved after treatment for 15 min, which slightly affects the moisture content, proteins, and wheat starch. CONCLUSION: Applying DDBD to wheat could effectively reduce the level of DON contamination, which provides a theoretical basis for applying cold plasma to the degradation of DON in wheat. © 2022 Society of Chemical Industry.
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Fusarium , Gases em Plasma , Humanos , Triticum/química , Espectrometria de Massas em Tandem , Contaminação de Alimentos/análise , Fusarium/metabolismoRESUMO
Endothelial progenitor cells (EPCs), which are precursors of endothelial cells (ECs), have the capacity to circulate, proliferate and differentiate into mature ECs. EPCs are primarily identified by the uptake of 1,1-dioctadecyl-3,3,3,3-tetramethylindocarbocyanine-labelled acetylated low-density lipoprotein (Dil-acLDL) and the binding of fluorescein-isothiocyanate (FITC)-conjugated Ulex europaeus agglutinin lectin (FITC-UEA-I). However, the cytoplasm and nucleus are usually stained by FITC-UEA-I via a typical method to double-stain late EPCs. It is necessary to explore a new method to improve the quality of fluorescence photomicrographs of late EPCs stained with FITC-UEA-I. Here, we described an updated protocol for double-staining late EPCs with Dil-acLDL and FITC-UEA-I, with the cells more optimally stained with FITC-UEA-I.
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Células Progenitoras Endoteliais , Coloração e RotulagemRESUMO
Differences of cytotoxicity associated with exposure to different extracts of atmospheric particulate matters (PMs) are still not well characterized by in vitro toxicoproteomics. In this study, in vitro cytotoxicity assays and toxicoproteomic analyses were carried out to investigate toxic effects of PM collected using polytetrafluoroethylene (PTFE) filters extracted with acetone for PM2.1 and water for PM2.1 and PM10 on A549 human lung epithelial cells. The cytotoxicity assays based on cell viability, cell apoptosis and reactive oxygen species generation indicated that PM2.1 extracted with acetone had the highest toxicity. iTRAQ labeling and LC-MS/MS analyses indicated that the number of differentially expressed proteins in A549 cells affected by PM2.1 extracted with acetone was noticeably higher than that of the other two groups. Hierarchical cluster analyses showed that the influences of the extracts of PM2.1 and PM10 using water on the proteome of A549 cells were similar, whereas significantly different from the effect of PM2.1 extracted with acetone. Pathways analyses indicated that PM2.1 extracted with acetone influenced the expression of proteins involved in 14 pathways including glycolysis/gluconeogenesis, pentose phosphate pathway, proteasome, etc. PM2.1 extracted with water affected the expression of proteins involved in 3 pathways including non-homologous end-joining, ribosome and endocytosis. However, PM10 extracted with water affected the expression of proteins involved in only spliceosome pathway. The extracts of PM using different extractants to detach PM from PTFE filters influenced the cytotoxic effects of PM and the proteome of A549 cells. Therefore, extractants should be assessed carefully before the investigations on cytotoxicity to improve the compatibility of experimental results among research teams.
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Poluentes Atmosféricos/toxicidade , Material Particulado/toxicidade , Células A549 , Acetona , Apoptose , Atmosfera/química , Sobrevivência Celular/efeitos dos fármacos , Citotoxinas/toxicidade , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Politetrafluoretileno , Proteoma/metabolismo , Proteômica/métodos , ÁguaRESUMO
In vitro toxicological assessment helps explore key fractions of particulate matter (PM) in association with the toxic mechanism. Previous studies mainly discussed the toxicity effects of the water-soluble and organic-soluble fractions of PM. However, the toxicity of insoluble fractions is relatively poorly understood, and the adsorption of proteins is rarely considered. In this work, the formation of protein corona on the surface of insoluble particles during incubation in a culture medium was investigated. It was found that highly abundant proteins in fetal bovine serum were the main components of the protein corona. The adsorbed proteins increased the dispersion stability of insoluble particles. Meanwhile, the leaching concentrations of some metal elements (e.g., Cu, Zn, and Pb) from PM increased in the presence of proteins. The toxicity effects and potential mechanisms of the PM insoluble particle-protein corona complex on macrophage cells RAW264.7 were discussed. The results revealed that the PM insoluble particle-protein corona complex could influence the phagosome pathway in RAW264.7 cells. Thus, it promoted the intracellular reactive oxygen species generation and induced a greater degree of cell differentiation, significantly altering cell morphology. Consequently, this work sheds new light on the combination of insoluble particles and protein corona in terms of PM cytotoxicity assessment.
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Chrysanthemum indicum Linnén (C. indicum), a medicinal and food herb with various bioactive components, may be of beneficial use in cosmetics and the treatment of skin-related diseases. However, to date, few studies have been reported on its potential preventive and therapeutic effects on skin cancer. Therefore, the present study aimed to investigate the effect and potential mechanism of action of supercritical carbon dioxide extract from C. indicum (CISCFE) on UV-induced skin cancer in a mouse model. Kunming mice were allocated randomly to five treatment groups: Sham, model, low concentration CISCFE, high concentration CISCFE and positive control nicotinamide groups. The dorsal skin of mice was irradiated with UV light for 31 weeks. Histopathological changes, ELISA assays, immunohistochemical analysis and western blotting were performed to investigate the potential therapeutic effects of CISCFE. The results showed that CISCFE alleviated skin oxidative and inflammatory damage in a UV-induced mouse model of skin cancer. Moreover, CISCFE suppressed abnormal activation of proto-oncogene c-Myc and the overexpression of Ki-67 and VEGF, and increased expression of the anti-oncogene PTEN, thereby reducing abnormal proliferation of the epidermis and blood vessels. Additionally, CISCFE increased the protein expression levels of NAD-dependent protein deacetylase sirtuin-1 (SIRT1), Kelch-like ECH associated protein 1 (Keap1) and inhibited the expression of nuclear factor 2 erythroid 2-related factor 2 (Nrf2), phosphorylated (p)-p62 (Ser 349), p-p65 and acetyl-p65 proteins in a UV-induced skin cancer mouse model. In summary, CISCFE exhibited potent anti-skin cancer activity, which may be attributed its potential effects on the p62/Keap1-Nrf2 and SIRT1/NF-κB pathways.
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BACKGROUND: Benzoxazine is one of the most important privileged scaffolds in medicinal chemistry. Compounds bearing benzoxazine moiety usually have a variety of biological activities, such as anti-inflammatory, anti-microbial, anti-tuberculosis, anti- oxidant and anti-cancer activities. The fascinating bioactivity profile of benzoxazine scaffold in various fields has prompted medicinal chemists to design and discover novel benzoxazine derivatives as potential therapeutic candidates with the desired biological properties. OBJECTIVE: This review aimed to provide a comprehensive elucidation on the recent advances of benzoxazine derivatives in medicinal chemistry. METHODS: We have searched the recent literature about benzoxazine derivatives from the online resources and databases, such as PubMed, SciFinder and Google Scholar. RESULTS: Many benzoxazine derivatives with a wide range of bioactivities, such as anti- microbial, anti-cancer, anti-tuberculosis, anti-oxidant and anti-inflammatory, were summed up. Many compounds displayed good biological activities. CONCLUSION: Benzoxazine is a versatile structure and building block in medicinal chemistry. Benzoxazine derivatives have gained considerable attention from medicinal chemists due to their various pharmacological properties and multiple modification sites. This review might help medicinal chemists to seek new drug candidates with better bioactivities and pharmacokinetics properties.
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Benzoxazinas , Química Farmacêutica , Humanos , Benzoxazinas/farmacologia , Anti-Inflamatórios/farmacologia , Relação Estrutura-AtividadeRESUMO
Dielectric barrier discharge (DBD) cold plasma, as a new nonthermal technology, has attracted increasing attention in pesticide degradation. In this study, DBD plasma was used to degrade carbendazim (MBC) in aqueous solution. Under the optimal conditions (160 kv, 50 Hz), MBC solution (0.5 µg/mL) was degraded by 89.04% after plasma treatment for 10 min. Four MBC degradation products were identified, one of which was a common oxidative degradation product (5-hydroxycarbendazim, m/z 208.07); the others were identified (m/z 118.06, m/z 132.08 and m/z 104.05) to have formed by the cleavage of the benzimidazole heterocyclic ring. The degradation pathways were obtained by analysis of degradation products at different treatment times. The toxicity of the degradation products was estimated based on the survival rate of yeast, indicating much lower toxicity levels compared to that of MBC. This study provides a theoretical basis for the application of DBD plasma in the degradation of benzimidazole pesticides in foods.
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Gases em Plasma , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Carbamatos/toxicidade , Benzimidazóis/toxicidade , Benzimidazóis/análiseRESUMO
Astaxanthin is a carotenoid species with the highest antioxidant capability. Its natural resource is very rare. The biosynthesis of astaxanthin from ß-carotene includes a hydroxylation step and a ketolation step, for which the corresponding enzymes have been characterized in a few species. However, the sequence of these two reactions is unclear, and may vary with different organisms. In this study, we aimed to elucidate this sequence in Synechocystis, which is an ideal cyanobacterial synthetic biology chassis. We first silenced the endogenous carotene oxygenase gene SyneCrtO to avoid its possible interference in the carotenoid metabolic network. We then introduced the ß-carotene ketolase gene from Haematococcus pluvialis (HpBKT) and the CrtZ-type carotene ß-hydroxylase gene from Pantoea agglomerans (PaCrtZ) to this δCrtO strain. Our pigment analysis demonstrated that both the endogenous CrtR-type carotene hydroxylase SyneCrtR and HpBKT have the preference to use ß-carotene as their substrate for hydroxylation and ketolation reactions to produce zeaxanthin and canthaxanthin, respectively. However, the endogenous SyneCrtR is not able to further catalyze the 3,3'-hydroxylation of canthaxanthin to generate astaxanthin. From our results, a higher accumulation of canthaxanthin and a much lower level of astaxanthin, as confirmed using liquid chromatography-tandem mass spectrometry analysis, were detected in our transgenic BKT+/CrtZ+/δCrtO cells. Therefore, we proposed that the bottleneck for the heterologous production of astaxanthin in Synechocystis might exist at the hydroxylation step, which requires a comprehensive screening or genetic engineering for the corresponding carotene hydroxylase to enable the industrial production of astaxanthin.
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Currently, heterocycles have occupied an important position in the fields of drug design. Among them, azaindole moiety is regarded as one privileged scaffold to develop therapeutic agents. Since two nitrogen atoms of azaindole increase the possibility to form hydrogen bonds in the adenosine triphosphate (ATP)-binding site, azaindole derivatives are important sources of kinase inhibitors. Moreover, some of them have been on the market or in clinical trials for the treatment of some kinase-related diseases (e.g., vemurafenib, pexidartinib, decernotinib). In this review, we focused on the recent development of azaindole derivatives as potential kinase inhibitors based on kinase targets, such as adaptor-associated kinase 1 (AAK1), anaplastic lymphoma kinase (ALK), AXL, cell division cycle 7 (Cdc7), cyclin-dependent kinases (CDKs), dual-specificity tyrosine (Y)-phosphorylation regulated kinase 1A (DYRK1A), fibroblast growth factor receptor 4 (FGFR4), phosphatidylinositol 3-kinase (PI3K) and proviral insertion site in moloney murine leukemia virus (PIM) kinases. Meanwhile, the structure-activity relationships (SARs) of most azaindole derivatives were also elucidated. In addition, the binding modes of some azaindoles complexed with kinases were also investigated during the SARs elucidation. This review may offer an insight for medicinal chemists to rationally design more potent kinase inhibitors bearing the azaindole scaffold.
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Desenho de Fármacos , Fosfatidilinositol 3-Quinases , Camundongos , Animais , Relação Estrutura-Atividade , Sítios de Ligação , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/químicaRESUMO
The static and dynamic compressions of closed-cell ethylene-vinyl acetate (EVA) foams with different densities were conducted under various strain rates. The stress-strain curves were processed to determine the corresponding curves of energy absorption per unit volume and energy absorption efficiency, and energy absorption diagrams were produced. The influences of density and strain rate on the elastic modulus, yield strength, energy absorption per unit volume, optimal strain, densification strain, and energy absorption diagrams were analyzed and discussed. The whole stress-strain curve can be fitted with the Rusch formula. The strain rate does not change the shape of stress-strain curve, and has little influence on the elastic modulus. There exists the optimal density of EVA foam corresponding to its maximum energy absorption efficiency. Under a fixed strain rate, the optical energy absorption per unit volume is proportional to the optical stress on the envelope line in the energy absorption diagrams of EVA foams with different densities. The change in strain rate leads to the envelope line in the energy absorption diagrams of EVA foams with a given density having the larger slope and a negative intercept where the optical energy absorption per unit volume relies linearly on the optical stress. The empirical formulas of elastic modulus, yield strength, optimal strain, and envelope lines and their slopes are derived from the tested results.
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Cimicifugae Rhizoma, a well-known botanical dietary supplement, has been the subject of intense interest due to its potential application for alleviating menopausal symptom. Although there are clinic data that the Cimicifuga extract should have hepatotoxicity, no evidence on the main chemical components has been reported. Cimicidol-3-O-ß -d-xyloside (CX) is one of the main triterpenoids of the rhizome. This work studies the toxicological effects of CX after oral administration (50 mg kg(-1) per day) over a 7-day period in female SD rats using metabonomic analyses of (1) H NMR spectra of urine, serum and liver tissue extracts. Histopathological studies of liver and analyses of blood biochemical parameter, such as alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, blood urea nitrogen and creatinine revealed that CX had no negative impacts on liver and kidney. However, the metabolic signature of (1) H NMR-based urinalysis of daily samples displayed an increment in the levels of taurine, trimethylamine-N-oxide (TMAO), betaine and acetate. Elevated serum levels of creatinine, glucose, alanine, TMAO and betaine and lower levels of lactate were observed. Metabolic profiling on aqueous soluble extracts of liver showed simultaneously increases in succinate, glycogen, choline, glycerophosphorylcholine, TMAO and betaine levels and reduction in valine, glucose and lactate levels. Nevertheless, no changes in any metabonomic level were found in lipid-soluble extracts of liver. These findings indicate that CX has a slight toxicity in liver and kidney via disturbance of the metabolisms of energy and amino acids. The present study provides a reasonable explanation for the clinical hepatotoxicity of Cimicifuga extract.
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Cimicifuga/química , Glicosídeos/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos , Animais , Feminino , Glicosídeos/administração & dosagem , Glicosídeos/química , Humanos , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Metaboloma , Metabolômica/instrumentação , Extratos Vegetais/química , Análise de Componente Principal , RatosRESUMO
A new design of linear piezoelectric actuator using "A-shaped" structure was proposed, designed, fabricated, and tested. By fusion design of the piezoelectric transducer and the mechanical structure, the proposed actuator only uses the first bending vibration of the center piezoelectric transducer to work. Frequency degeneration is no longer needed, which enables the actuator to adjust its structural parameters according to the application conditions. When applying an alternating voltage at resonance frequency, the center piezoelectric transducer will be stimulated in the first bending vibration. The vibration energy transmitted to the two driving arms generates alternating tilting movements with a phase difference of 180° between the two driving feet, which enables the actuator to push the linear guide when a vertical preload is applied. Under the preload of 120 N, the actuator gained a maximum thrust force of 9.8 N and a maximum output power of 0.62 W with a self-weight of 0.061 kg. The maximum output thrust density and the maximum output power density were 160.6 N/kg and 10.2 W/kg, respectively.
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Fenômenos Mecânicos , Transdutores , VibraçãoRESUMO
Laboratories use different strategies to sample and extract atmospheric particulate matter (PM), some of which can be very complicated. Due to the absence of a standard protocol, it is difficult to compare the results of PM toxicity assessment across different laboratories. Here, we proposed a novel PM sampling and cell exposure strategy based on agar membrane. The agar membrane, prepared by a simple freeze-drying method, has a relatively flat surface and porous interior. We demonstrated that the agar membrane was a reliable substitute material for PM sampling. Then the PM on the agar membranes was directly extracted with the culture medium by vortex method, and the PM on the polytetrafluoroethylene (PTFE) filters was extracted with water by the traditional ultrasonic method for comparison. The extraction efficiency was evaluated and in vitro cytotoxicity assays were carried out to investigate the toxic effects of PM extracted with two strategies on macrophage cells. The results showed that the PM extracted from agar membranes induced higher cytotoxicity and more differentially expressed proteins. Overall, the novel PM sampling-cell exposure strategy based on the agar membrane is easy to operate, biocompatible and comparable, and has low disturbance, could be an alternative sampling and extraction method for PM toxicity assessment.
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Poluentes Atmosféricos , Material Particulado , Ágar , Poluentes Atmosféricos/análise , Material Particulado/análise , ÁguaRESUMO
A theoretical model of the intermittent contact mechanism of linear piezoelectric actuator was proposed, in which the microscopic characteristics of the contact surfaces were taken into account. Greenwood-Williamson (GM) theory was involved for the first time to describe the microscopic characteristics of the contact surfaces in which the contact surfaces were considered as random rough surfaces that were composed of large amounts of asperities and the heights of the asperities conformed to a Gauss distribution. The developed theoretical model gives an insight into the influence of the microscopic properties, as well as the macroscopic and material properties on the output performance of the actuator, which may provide guidance for the design of such type of piezoelectric actuator. During the modeling, normal kinetic contact force, kinetic friction coefficient, friction force and steady-state output force of were obtained in sequence. And some simulations were carried out to analyze how factors such as the type of material, the roughness of the contact surface, the initial distance between the stator and the rotor, and the preload, et.al, affect the contact performance. A set of experiments were carried out to reveal the influence of surface roughness, material type and preload on the steady-state output thrust. The simulated results were found in good agreement with the experiment ones at most of the tested points. Finally, surface roughness of the stator and rotor were tested before and after the operation, which indicated that the rotor and stator had similar roughness after operation.
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Currently, the arise of drug resistance and undesirable off-target effects of anti-cancer agents are major challenges for cancer treatment, which energizes medicinal chemists to develop more anti-cancer agents with high efficiency and low toxicity continuously. Sulfonamide derivatives are a class of promising compounds with diverse biological activities including anti-cancer, and parts of them have been marketed for cancer therapy, such as Belinostat, ABT-199 and Amsacrine. In this review, we summed up the recent advances of sulfonamide derivatives as potential anti-cancer agents based on the anti-cancer targets, such as aromatase, carbonic anhydrase (CA), anti-apoptotic B-cell lymphoma-2 (Bcl-2) proteins, topoisomerase and phosphatidylinositol 3-kinase (PI3K), and elucidated the corresponding structure-activity relationships (SARs) of most sulfonamide derivatives. We hope this review could provide a clear insight for medicinal chemists in the rational design of more potent and bio-target specific anti-cancer agents.
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Antineoplásicos/farmacologia , Sulfonamidas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Sulfonamidas/síntese química , Sulfonamidas/químicaRESUMO
BACKGROUND: Non-small-cell lung cancer (NSCLC) accounts more than 80% of the lung cancer cases. Polysaccharides in rice bran and its fermentation products have been proven to suppress many cancers. However, the report on inhibiting NSCLC is few. In this paper, the polysaccharides with suppression activity to H1299 NSCLC in the fermentation products of full-fat rice bran and defatted rice bran were studied in vitro and in vivo. METHOD: Polysaccharides (GSRBPs) were extracted from Ganoderma sinense - full-fat rice bran (GS-FRB) and Ganoderma sinense - defatted rice bran (GS-DRB) fermentation products. The structure information of the GSRBPs was studied using HPLC analysis. The anti-tumor activities on H1299 NSCLC of GSRBPs in vitro study was performed using MTT method. The in vivo studies use BALB/c-nu nude mice as H1299 NSCLC bearing mice. RESULT: All the polysaccharides contained two fractions, GSFPS-1 and GSFPS-2. The molecular weight and the ratio of GSFPS-1 and GSFPS-2 were different in GS-FRB and GS-DRB. At the earlier state of fermentation, all polysaccharides were composed of D-glu, D-man, D-xyl and L-ara with certain molar ratios. But at the latter stage, polysaccharides in GS-FRB were composed of D-glu, D-man, D-xyl, L-ara and D-fru, while these in GS-DRB only composed of D-glu and D-man. In the in vitro study, the IC50 of RBS and GSRBPs was as GS-DRB-11 (40.62 µg/mL), GS-FRB-9 (43.82 µg/mL), GS-DRB-7 (48.08 µg/mL), RBS (49.56 µg/mL), GS-DRB-9 (49.91 µg/mL), GS-DRB-13 (51.89 µg/mL), GS-FRB-11 (53.75 µg/mL), GS-FRB-7 (56.84 µg/mL), GS-DRB-13 (60.63 µg/mL) from small to large. In the in vivo study, the H1299 NSCLC inhibition rate (InRa) of RBS and GSRBPs were GS-DRB-11 (86.81%) > GS-DRB-9 (86.01%) > GS-FRB-9 (84.88%) > GS-DRB-7 (82.21%) > GS-DRB-13 (78.04%) > RBS (76.06%) > GS-FRB-13 (65.44%) > GS-FRB-11 (64.70%) > GS-FRB-7 (27.87%). The GSFPS-2 area percent was negatively correlated to the IC50 and was positively correlated to the InRa. This means the GSFPS-2 had much higher anti-tumor activity than GSFPS-1. CONCLUSION: GSFPS-2 had higher anti-tumor activities, and the lipid in the rice bran has a decisive effect on the structures of polysaccharides produced by fermentation. Therefore, GSRBPs could be considered as potential novel agents to suppress H1299 non-small-cell lung cancer.