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This paper begins by exploring the challenge of event-triggered state estimations in nonlinear systems, grappling with packet dropout and correlated noise. A communication mechanism is introduced that determines whether to transmit measurement values based on whether event-triggered conditions are violated, thereby minimizing redundant communication data. In designing the filter, noise decorrelation is initially conducted, followed by the integration of the event-triggered mechanism and the unreliable network transmission system for state estimator development. Subsequently, by combining the three-degree spherical-radial cubature rule, the numerical implementation steps of the proposed state estimation framework are outlined. The performance estimation analysis highlights that by adjusting the event-triggered threshold appropriately, the estimation performance and transmission rate can be effectively balanced. It is established that when there is a lower bound on the packet dropout rate, the covariance matrix of the state estimation error remains bounded, and the stochastic stability of the state estimation error is also confirmed. Ultimately, the algorithm and conclusions that are proposed in this paper are validated through a simulation example of a target tracking system.
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In this paper, we consider the problem of asynchronous estimation in the presence of packet losses for the randomly sampling nonlinear system. Packet losses occur at the control input and at the measurement side. Firstly, the synchronization of the asynchronous sampling system is realized by weighting the state of the adjacent state update points. Secondly, the projection theorem is used to estimate the system state at the sampling time. Due to modeling errors and unmodeled dynamics, obtaining an accurate dynamic model is challenging. Therefore, observation inference based on interpolation techniques is proposed to solve the asynchronous estimation problem. Furthermore, the algorithm is extended to multi-sensor systems to obtain a distributed fusion estimator. Finally, simulation experiments are conducted to validate the effectiveness of the algorithm.
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CRISPR/Cas9-based gene therapy and photodynamic therapy both show promise for cancer treatment but still have their drawbacks limited by tumor microenvironment and long treatment duration. Herein, CRISPR/Cas9 genome editing and photodynamic strategy for a synergistic anti-tumor therapeutic modality is merged. Chlorophyll (Chl) extracted from natural green vegetables is encapsulated in Pluronic F127 (F127) micelles and Histidine-tagged Cas9 can be effectively chelated onto micelles via metal coordination by simple incubation, affording Cas9-Chl@F127 micelles. Mg2+ acts as an enzyme cofactor to correlatively enhance Cas9 gene-editing activity. Upon laser irradiation, Chl as an effective photosensitizer generates reactive oxygen species (ROS) to kill tumor cells. Meanwhile, CRISPR/Cas9, mediated by dual deliberately designed gRNAs of APE1 and NRF2, can reprogram the tumor microenvironment by increasing the intracellular oxygen accumulation and impairing the oxidative defense system of tumor cells. Cas9-Chl@F127 micelles can responsively release Cas9 in the presence of abundant ATP or low pH in tumor cells. In a murine tumor model, Cas9-Chl@F127 complexed with dual gRNAs including APE1 and NRF2 significantly inhibits the tumor growth. Taken together, Cas9-Chl@F127 micelles, representing the first Chl-based green biomaterial for the delivery of Cas9, show great promise for the synergistic anti-tumor treatment by PDT and gene editing.
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Neoplasias , Fotoquimioterapia , Ratones , Animales , Micelas , Edición Génica , Clorofila , Sistemas CRISPR-Cas/genética , Factor 2 Relacionado con NF-E2 , Neoplasias/genética , Neoplasias/terapiaRESUMEN
The use of orally-administered therapeutic proteins for treatment of inflammatory bowel disease (IBD) has been limited due to the harsh gastrointestinal environment and low bioavailability that affects delivery to diseased sites. Here, a nested delivery system, termed Gal-IL10-EVs (C/A) that protects interleukin 10 (IL-10) from degradation in the stomach and enables targeted delivery of IL-10 to inflammatory macrophages infiltrating the colonic lamina propria, is reported. Extracellular vesicles (EVs) carrying IL-10 are designed to be secreted from genetically engineered mammalian cells by a plasmid system, and EVs are subsequently modified with galactose, endowing the targeted IL-10 delivery to inflammatory macrophages. Chitosan/alginate (C/A) hydrogel coating on Gal-IL10-EVs enables protection from harsh conditions in the gastrointestinal tract and favorable delivery to the colonic lumen, where the C/A hydrogel coating is removed at the diseased sites. Gal-IL10-EVs control the production of reactive oxygen species (ROS) and inhibit the expression of proinflammatory cytokines. In a murine model of colitis, Gal-IL10-EVs (C/A) alleviate IBD symptoms including inflammatory responses and disrupt colonic barriers. Taken together, Gal-IL10-EVs (C/A) features biocompatibility, pH-responsive drug release, and macrophage-targeting as a therapeutic platform for oral delivery of bioactive proteins for treating intestinal diseases.
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Quitosano , Vesículas Extracelulares , Enfermedades Inflamatorias del Intestino , Ratones , Animales , Citocinas , Interleucina-10 , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/metabolismo , Vesículas Extracelulares/metabolismo , Hidrogeles , MamíferosRESUMEN
Cancer vaccines generally are limited by insufficient tumor-specific cellular immunogenicity. Herein, a potent "ABC" ternary membrane-derived vaccine system blended from antigen-presenting mature dendritic cell membranes ("A"), bacterial E. coli cytoplasmic membranes ("B"), and cancer cell membranes ("C") is developed using a block-copolymer micelle-enabled approach. The respective ABC membrane components provide for a source of cellular immune communication/activation and enhanced accumulation in lymph nodes (A), immunological adjuvant (B), and tumor antigens (C). The introduction of dendritic cell (DC) membranes enables multiple cell-to-cell communication and powerful immune activation. ABC activates dendritic cells and promotes T-cell activation and proliferation in vitro. In vivo, ABC is 14- and 304-fold more immunogenic than binary (BC) and single (C) membrane vaccines, and immunization with ABC enhances the frequency of tumor-specific cytotoxic T lymphocytes, leading to an 80% cure rate in tumor-bearing mice. In a surgical resection and recurrence model, ABC prevents recurrence with vaccination from autologous cancer membranes, and therapeutic effects are observed in a lung metastasis model even with heterologous cancer cell membranes. ABCs formed from human cancer patient-derived tumor cells activate human monocyte-derived dendritic cells (moDC). Taken together, the ternary ABC membrane system provides the needed functional components for personalized cancer immunotherapy.
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Vacunas contra el Cáncer , Neoplasias , Humanos , Animales , Ratones , Escherichia coli , Células Dendríticas , Neoplasias/tratamiento farmacológico , Linfocitos T Citotóxicos , Antígenos de Neoplasias , InmunoterapiaRESUMEN
Hypoxia is a remarkable trait of the tumor microenvironment (TME). When facing selective pressure, tumor cells show various adaptive characteristics, such as changes in the expression of cancer hallmarks (increased proliferation, suppressed apoptosis, immune evasion, and so on) and more frequent cell communication. Because of the adaptation of cancer cells to hypoxia, exploring the association between cell communication mediators and hypoxia has become increasingly important. Exosomes are important information carriers in cell-to-cell communication. Abundant evidence has proven that hypoxia effects in the TME are mediated by exosomes, with the occasional formation of feedback loops. In this review, we equally focus on the biogenesis and heterogeneity of cancer-derived exosomes and their functions under hypoxia and describe the known and potential mechanism ascribed to exosomes and hypoxia. Notably, we call attention to the size change of hypoxic cancer cell-derived exosomes, a characteristic long neglected, and propose some possible effects of this size change. Finally, jointly considering recent developments in the understanding of exosomes and tumors, we describe noteworthy problems in this field that urgently need to be solved for better research and clinical application.
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Exosomas/metabolismo , Hipoxia/metabolismo , Neoplasias/metabolismo , Neoplasias/patología , Microambiente Tumoral , Animales , Apoptosis , Transporte Biológico , Biomarcadores , Proliferación Celular , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Resistencia a Antineoplásicos , Metabolismo Energético , Regulación Neoplásica de la Expresión Génica , Humanos , Hipoxia/genética , Neoplasias/etiología , Neoplasias/terapia , Transducción de Señal , Microambiente Tumoral/genéticaRESUMEN
In the tumor microenvironment, there exist microorganisms that metabolize anticancer drugs, leading to chemotherapy failure. To solve this problem, herein, we develop antibiotic and anticancer drug co-delivery micelles, termed colistin crosslinked gemcitabine micelle (CCGM). A self-immolative linker enables colistin and gemcitabine to be released on demand without affecting their antibacterial and anticancer effects. Once CCGM is delivered to the tumor microenvironment, intracellular glutathione triggers the release of colistin and gemcitabine, inhibiting the growth of microbes in the tumor, thus eliminating the microbe-induced drug resistance of tumor.
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Antineoplásicos , Micelas , Colistina/farmacología , Resistencia a Antineoplásicos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Glutatión , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Línea Celular Tumoral , GemcitabinaRESUMEN
OBJECTIVE: Distal-less homeobox 6 (DLX6) has been reported to play important roles in the development of craniofacial structures, inner ear, limb, and brain. We found in our previous investigation that DLX6 was significantly highly expressed in oral cancer tissues in The Cancer Genome Atlas database. This study aimed to explore its roles and regulation mechanism in oral squamous cell carcinoma. MATERIALS AND METHODS: We analyzed the expression of DLX6 and its association with overall survival in OSCC by real-time quantitative PCR. Besides, clone formation, proliferation, and apoptosis were detected after knocking down DLX6 and microarray analysis was performed to explore the possible regulatory mechanism. RESULTS: DLX6 was overexpressed in oral cancer tissues and was associated with advance tumor stage and poor prognosis. In vitro studies have shown that DLX6 promotes proliferation and inhibits cell apoptosis in oral cancer cells. Microarray analysis along with Western blotting results indicated that DLX6 significantly associated with malignant tumors and may regulate OSCC cells proliferation through EGFR-CCND1 axis. CONCLUSION: DLX6 promotes cell proliferation and suppresses cell apoptosis in oral cancer cells. EGFR-CCND1 pathway might be the potential mechanism participating in the regulating axis.
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Neoplasias de Cabeza y Cuello , Proteínas de Homeodominio , Neoplasias de la Boca , Carcinoma de Células Escamosas de Cabeza y Cuello , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Neoplasias de la Boca/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/genéticaRESUMEN
The low mechanical efficiency of metal belt's continuously variable transmission (CVT) limits its application in new energy vehicles. To further improve CVT efficiency and reduce the energy consumption of electric vehicles (EVs) with CVT, this paper proposes a pure electric CVT configuration and a clamping force control strategy. The slip characteristics of CVT are obtained through a bench test, the dynamic model of CVT slip is established, and a clamping force fuzzy control strategy is designed. The strategy is studied by simulation under extreme conditions and standard driving cycles. The simulation results show that the proposed clamping force control strategy has good adaptability. Under extreme conditions, this strategy can ensure that CVT does not undergo macro slip, while reducing the clamping force by 12.86-21.65%. Energy consumption per 100 km is 14.90 kWh in NEDC, which is 6.67% lower compared with the traditional strategy. CVT average efficiency and average transmission efficiency increased by 3.71% and 6.40%. The research results demonstrate that adjusting the CVT clamping force through fuzzy control based on the slip rate can improve the CVT efficiency and energy economy of EVs, which provides a certain reference for CVT clamping force control strategy development and the application of CVT on EVs.
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Polymeric ultrafine fibrous membranes (UFMs) with high thermal stability and high whiteness are highly desired in modern optoelectronic applications. A series of fluoro-containing polyimide (FPI) UFMs with high whiteness, good thermal stability, and good hydrophobicity were prepared via a one-step electrospinning procedure from the organo-soluble FPI resins derived from a fluoro-containing dianhydride, 4,4'-(hexafluoroisopropylidene) diphthalic anhydride (6FDA), and various diamines containing either pendant trifluoromethyl (-CF3) groups or alicyclic units in the side chains. The obtained FPI UFMs, including FPI-1 from 6FDA and 3,5-diaminobenzotrifluoride (TFMDA), FPI-2 from 6FDA and 2'-trifluoromethyl-3,4'-oxydianiline (3FODA), FPI-3 from 6FDA and 1,4-bis[(4-amino-2-trifluoromethyl)phenoxy]benzene (6FAPB), FPI-4 from 4,4'-bis[(4-amino-2-trifluoromethyl)phenoxy]biphenyl (6FBAB), and FPI-5 from 6FDA and 4'-tert-butyl-cyclohexyl-3,5-diaminobenzoate (DABC) showed whiteness indices (WI) higher than 87.00 and optical reflectance values higher than 80% at the wavelength of 457 nm (R457), respectively. The FPI-5 UFM, especially, showed the highest WI of 92.88. Meanwhile, the prepared PI UFMs exhibited good hydrophobic features with water contact angles (WCA) higher than 105°. At last, the PI UFMs exhibited good thermal stability with glass transition temperatures (Tg) higher than 255 °C, and the 5% weight-loss temperatures (T5%) higher than 510 °C in nitrogen.
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Anhídridos , Polímeros , Anhídridos/química , Diaminas/química , Interacciones Hidrofóbicas e Hidrofílicas , Polímeros/química , Temperatura de TransiciónRESUMEN
The oxygen reduction reaction (ORR) is essential in many life processes and energy conversion systems. It is desirable to design transition metal molecular catalysts inspired by enzymatic oxygen activation/reduction processes as an alternative to noble-metal-Pt-based ORR electrocatalysts, especially in view point of fuel cell commercialization. We have fabricated bio-inspired molecular catalysts electrografted onto multiwalled carbon nanotubes (MWCNTs) in which 5,10,15,20-tetra(pentafluorophenyl) iron porphyrin (iron porphyrin FeF20 TPP) is coordinated with covalently electrografted axial ligands varying from thiophene to imidazole on the MWCNTs' surface. The catalysts' electrocatalytic activity varied with the axial coordination environment (i. e., S-thiophene, N-imidazole, and O-carboxylate); the imidazole-coordinated catalyst MWCNTs-Im-FeF20 TPP exhibited the highest ORR activity among the prepared catalysts. When MWCNT-Im-FeF20 TPP was loaded onto the cathode of a zinc-air battery, an open-cell voltage (OCV) of 1.35â V and a maximum power density (Pmax ) of 110â mW cm-2 were achieved; this was higher than those of MWCNTs-Thi-FeF20 TPP (OCV=1.30â V, Pmax =100â mW cm-2 ) and MWCNTs-Ox-FeF20 TPP (OCV=1.28â V, Pmax =86â mW cm-2 ) and comparable with a commercial Pt/C catalyst (OCV=1.45â V, Pmax =120â mW cm-2 ) under similar experimental conditions. This study provides a time-saving method to prepare covalently immobilized molecular electrocatalysts on carbon-based materials with structure-performance correlation that is also applicable to the design of other electrografted catalysts for energy conversion.
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Nanotubos de Carbono , Porfirinas , Hierro , Ligandos , Oxidación-Reducción , OxígenoRESUMEN
Long noncoding RNAs (lncRNAs) has been acknowledged in tumorigenesis gradually because of the great importance in different cancers. LncRNA nuclear enriched abundant transcript 1 (NEAT1) is a novel lncRNA and has been reported to promote multiple cancer progression. However, the biological roles of NEAT1 in hepatocellular carcinoma (HCC) is not cleared nowadays. In the present research, the level of NEAT1 was found to be upregulated in HCC by The Cancer Genome Atlas. In addition, NEAT1 expression is negatively correlated with the survival rate in HCC. Further investigation revealed that NEAT1 upregulation inhibited sorafenib efficacy and promoted autophagy. We found that NEAT1 could be a sponge for microRNA-204 (miR-204) and inhibits its level to upregulate ATG3 expression. In addition to the above, we demonstrated that miR-204 mimics also attenuated tumor autophagy. And rescue assays demonstrated that NEAT1 promotes HCC autophagy through modulating miR-204/ATG3 pathway. Collectively, this study first demonstrated that a novel NEAT1/miR-204/ATG3 signaling regulates HCC progression.
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Proteínas Relacionadas con la Autofagia/genética , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , MicroARNs/genética , ARN Largo no Codificante/genética , Enzimas Ubiquitina-Conjugadoras/genética , Autofagia/efectos de los fármacos , Carcinogénesis , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Sorafenib/farmacologíaRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC) is a significant clinical challenge, and the mechanisms underlying HCC pathogenesis remain incompletely understood. Colon cancer associated transcript 1 (CCAT1), is one novel long noncoding RNA (lncRNA) which is upregulated in HCC. Autophagy is a vital process in HCC progression, and it is unknown whether CCAT1 regulates autophagy in HCC. MATERIALS AND METHODS: Immunofluorescence staining and transmission electron microscopy were used to analyze autophagy activity. Luciferase assay was performed to confirm miRNA-181a-5p (miR-181a-5p) bind CCAT1 and ATG7. RESULTS: CCAT1 levels were higher in tissue and cell lines of HCC. In function research, we found that CCAT1 facilitates HCC cell autophagy and cell proliferation. Our results show that, mechanistically, CCAT1 promotes autophagy through functioning as a sponge for miR-181a-5p, and then regulating ATG7 expression. CONCLUSION: Our findings indicate CCAT1 may play a role in regulating autophagy by sponging miR-181a-5p in HCC.
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Proteína 7 Relacionada con la Autofagia/metabolismo , Autofagia/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Secuencia de Bases , Carcinoma Hepatocelular/ultraestructura , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/ultraestructura , ARN Largo no Codificante/genética , Regulación hacia Arriba/genéticaRESUMEN
BACKGROUND: Emerging evidence indicates that tumor cells release a large amount of exosomes loaded with cargos during tumorigenesis. Exosome secretion is a multi-step process regulated by certain related molecules. Long non-coding RNAs (lncRNAs) play an important role in hepatocellular carcinoma (HCC) progression. However, the role of lncRNA HOTAIR in regulating exosome secretion in HCC cells remains unclear. METHODS: We analyzed the relationship between HOTAIR expression and exosome secretion-related genes using gene set enrichment analysis (GSEA). Nanoparticle tracking analysis was performed to validate the effect of HOTAIR on exosome secretion. The transport of multivesicular bodies (MVBs) after overexpression of HOTAIR was detected by transmission electron microscopy and confocal microscopy analysis of cluster determinant 63 (CD63) with synaptosome associated protein 23 (SNAP23). The mechanism of HOTAIR's regulation of Ras-related protein Rab-35 (RAB35), vesicle associated membrane protein 3 (VAMP3), and SNAP23 was assessed using confocal co-localization analysis, phosphorylation assays, and rescue experiments. RESULTS: We found an enrichment of exosome secretion-related genes in the HOTAIR high expression group. HOTAIR promoted the release of exosomes by inducing MVB transport to the plasma membrane. HOTAIR regulated RAB35 expression and localization, which controlled the docking process. Moreover, HOTAIR facilitated the final step of fusion by influencing VAMP3 and SNAP23 colocalization. In addition, we validated that HOTAIR induced the phosphorylation of SNAP23 via mammalian target of rapamycin (mTOR) signaling. CONCLUSION: Our study demonstrated a novel function of lncRNA HOTAIR in promoting exosome secretion from HCC cells and provided a new understanding of lncRNAs in tumor cell biology.
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Carcinoma Hepatocelular/genética , Exosomas/metabolismo , Neoplasias Hepáticas/genética , Proteínas Qb-SNARE/metabolismo , Proteínas Qc-SNARE/metabolismo , ARN Largo no Codificante/genética , Proteínas de Unión al GTP rab/metabolismo , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Movimiento Celular , Progresión de la Enfermedad , Exosomas/genética , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Microscopía Confocal , Microscopía Electrónica de Transmisión , Fosforilación , Transporte de Proteínas , Proteínas Qb-SNARE/genética , Proteínas Qc-SNARE/genética , Transducción de Señal , Proteínas de Unión al GTP rab/genéticaRESUMEN
The oxygen reduction reaction (ORR) is one of the most important reactions in life processes and energy conversion systems. To alleviate global warming and the energy crisis, the development of high-performance electrocatalysts for the ORR for application in energy conversion and storage devices such as metal-air batteries and fuel cells is highly desirable. Inspired by the biological oxygen activation/reduction process associated with heme- and multicopper-containing metalloenzymes, iron and copper-based transition-metal complexes have been extensively explored as ORR electrocatalysts. Herein, an outline into recent progress on non-precious-metal electrocatalysts for the ORR is provided; these electrocatalysts do not require pyrolysis treatment, which is regarded as desirable from the viewpoint of bioinspired molecular catalyst design, focusing on iron/cobalt macrocycles (porphyrins, phthalocyanines, and corroles) and copper complexes in which the ORR activity is tuned by ligand variation/substitution, the method of catalyst immobilization, and the underlying supporting materials. Current challenges and exciting imminent developments in bioinspired ORR electrocatalysts are summarized and proposed.
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BACKGROUND: Anopheles sinensis is the primary vector of vivax malaria in China and its control is under great threat as the development of insecticide resistance. In contrast to physiological resistance, there is no report of behavioural modifications of resistant An. sinensis after long-term insecticide use, despite their huge potential impact on malaria transmission. METHODS: Larvae or pupae of An. sinensis were collected from Yuanyang, Bishan, and Wuhe counties from southwestern to eastern China. Resistance to deltamethrin was assayed using the standard World Health Organization (WHO) susceptibility test. The frequency distribution of the kdr allele of the para-type sodium channel gene was determined by polymerase chain reaction (PCR) amplification and DNA sequencing. Contact repellency to deltamethrin-impregnated bed nets was evaluated using a modified WHO cone bioassay. RESULTS: All contemporary field populations for all three geographic locations were resistant to deltamethrin, with mortality ranging from 6.00 to 26.79%. Three kdr genotypes with either an L1014F or L1014C substitution with frequencies of 76.10-100% were identified in the Bishan and Wuhe populations, but no kdr mutations were detected in the Yuanyang samples despite high phenotypic resistance. The susceptible mosquitoes exhibited significantly longer flying time and more takeoffs on deltamethrin-treated bed nets (DTN) than on untreated bed nets (UTN), suggestive of robust avoidance behaviour. However, no significant increases in the frequency of takeoffs or flying time were observed in deltamethrin-resistant An. sinensis populations when exposed on DTNs, regardless of the presence of a kdr mutation. Moreover, the first takeoff from DTNs by resistant mosquitoes significantly lagged behind compared to susceptible mosquitoes. CONCLUSION: The An. sinensis populations were highly resistant to deltamethrin and exhibited decreased avoidance behaviour. Behavioural modification significantly associated with deltamethrin resistance, but not directly related to the presence of kdr mutations, indicating that there are additional factors contributing to the changes.
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Anopheles/efectos de los fármacos , Proteínas de Insectos/genética , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Mosquitos Vectores/efectos de los fármacos , Piretrinas/farmacología , Animales , Anopheles/crecimiento & desarrollo , Anopheles/fisiología , Reacción de Prevención/efectos de los fármacos , Femenino , Genotipo , Proteínas de Insectos/metabolismo , Larva/efectos de los fármacos , Larva/fisiología , Malaria Vivax , Mosquitos Vectores/crecimiento & desarrollo , Mosquitos Vectores/fisiología , Pupa/efectos de los fármacos , Pupa/fisiologíaRESUMEN
Oxygen reduction reaction (ORR) catalyzed by a bio-inspired iron porphyrin bearing a hanging carboxylic acid group over the porphyrin ring, and a tethered axial imidazole ligand was studied by DFT calculations. BP86 free energy calculations of the redox potentials and pK a's of reaction components involved in the proton coupled electron transfer (PCET) reactions of the ferric-hydroxo and -superoxo complexes were performed based on Born-Haber thermodynamic cycle in conjunction with a continuum solvation model. The comparison was made with iron porphyrins that lack either in the hanging acid group or axial ligand, suggesting that H-bond interaction between the carboxylic acid and iron-bound hydroxo, aquo, superoxo, and peroxo ligands (de)stabilizes the Fe-O bonding, resulting in the increase in the reduction potential of the ferric complexes. The axial ligand interaction with the imidazole raises the affinity of the iron-bound superoxo and peroxo ligands for proton. In addition, a low-spin end-on ferric-hydroperoxo intermediate, a key precursor for O-O cleavage, can be stabilized in the presence of axial ligation. Thus, selective and efficient ORR of iron porphyrin can be achieved with the aid of the secondary coordination sphere and axial ligand interactions.
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Hierro/química , Metaloporfirinas/química , Oxígeno/química , Teoría Cuántica , Ligandos , Oxidación-ReducciónRESUMEN
Rab5a was reported to be overexpressed in human malignancy and associated with the malignant phenotype. To data, its expression pattern and biological function in hepatocellular carcinoma (HCC) have not been studied. We analyzed Rab5a protein expression in 98 cases of HCC tissues and four HCC cell lines. We found that Rab5a expression was upregulated in HCC tissues and cell lines. Rab5a overexpression correlated with TNM stage and nodal metastasis (p < 0.05). To confirm the biological function of Rab5a in HCC cell lines, Rab5a siRNA was employed in SK-Hep-1 cell line and plasmid transfection was performed in Huh7 cell line. CCK-8 assay showed that Rab5a depletion blocked cell growth rate while Rab5a overexpression facilitated proliferation. Transwell and migration assay showed that Rab5a positively regulated cell invasion and migration. To explore the molecular mechanism underlying the biological effects of Rab5a, we checked several signaling pathways and found that Rab5a overexpression upregulated cyclin D1, cyclin E expression, FAK (Tyr397), and AKT (Ser473) phosphorylation. Blockage of FAK using inhibitor PF573228 abolished the role of Rab5a on cyclin D1. In conclusion, Rab5a is overexpressed in human HCC and contributes to cancer cell proliferation and invasion through regulation of FAK and AKT signaling.
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Carcinoma Hepatocelular/genética , Proliferación Celular/genética , Quinasa 1 de Adhesión Focal/genética , Neoplasias Hepáticas/genética , Transducción de Señal/genética , Proteínas de Unión al GTP rab5/genética , Western Blotting , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular , Línea Celular Tumoral , Movimiento Celular/genética , Ciclina D1/genética , Ciclina D1/metabolismo , Quinasa 1 de Adhesión Focal/metabolismo , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Invasividad Neoplásica , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas de Unión al GTP rab5/metabolismoRESUMEN
Rab25 was reported to be associated with several human cancers and malignant biological behavior of cancer cells. The goal of the present study was to determine its expression pattern and biological function in human hepatocellular carcinoma (HCC). We examined Rab25 protein in 92 cases of HCC tissues and 3 HCC cell lines. The results showed that Rab25 was upregulated in HCC tissues and cells compared with normal liver tissues and cell line. Rab25 overexpression correlated with advanced tumor stage and nodal metastasis. Rab25 small interfering RNA (siRNA) was employed in Bel7402 and SK-Hep-1 cell lines. Cell Counting Kit-8 (CCK-8) assay and colony formation assay showed that Rab25 depletion blocked cell growth rate and inhibited colony formation ability. Transwell assay showed that Rab25 depletion negatively regulated the invading ability of HCC cells. To explore the possible mechanisms, we checked several signaling pathways and found that Rab25 depletion downregulated AKT phosphorylation. In addition, luciferase reporter assay showed that Rab25 depletion inhibited the Wnt signaling pathway and its target genes such as cyclin D1, c-myc, and MMP7. In conclusion, Rab25 is overexpressed in human HCC and contributes to cancer cell proliferation and invasion possibly through regulation of the Wnt signaling pathway.
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Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Proteínas de Neoplasias/fisiología , Transducción de Señal/genética , Proteínas de Unión al GTP rab/fisiología , División Celular , Línea Celular Tumoral , Femenino , Células Hep G2 , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Fosforilación , Procesamiento Proteico-Postraduccional , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/genética , Ensayo de Tumor de Célula Madre , Vía de Señalización Wnt/genética , Proteínas de Unión al GTP rab/biosíntesis , Proteínas de Unión al GTP rab/genéticaRESUMEN
Heat shock protein 70 (HSP70) and HSP70-peptide complexes (HSP70-PCs) have been implicated in the pathogenesis of multiple tumors in humans and have been experimentally shown to increase the proliferation of cell lines derived from hepatocellular carcinoma. The goal of this study was to elucidate the molecular mechanisms through which extracellular HSP70/HSP70-PCs stimulate the proliferation of hepatocellular carcinoma (HCC). The molecular mechanisms of HSP70/HSP70-PC action were studied in the human hepatocellular carcinoma cell lines HepG2 and Huh-7, as well as tumor tissue collected from patients with HCC (n = 95). We found that HSP70/HSP70-PCs can stimulate the proliferation of HepG2 cells and that this effect is blocked by knocking down TLR2 and TLR4 expression by RNA interference. A physical interaction between HSP70/HSP70-PCs and TLR2/4 was established using co-immunoprecipitation and pull-down assays. Pharmacological inhibition of different branches of the MAPK intracellular signaling pathway indicated that the extracellular HSP70/HSP70-PC effect was mediated by the JNK1/2 signaling pathway within the cell. We also studied TLR2 and TLR expression at the protein and messenger RNA (mRNA) level in tumor and non-tumor tissue in patients with HCC (n = 95), finding that TLR2 and 4 are increased in HCC tumor tissue and that the expression of TLR2 correlates with clinicopathologic features of HCC. Our data conclusively demonstrates that extracellular HSP70/HSP70-PCs can promote the proliferation of HCC cells through activation of TLR2 and TLR4 and subsequent activation of the intracellular JNK1/2/MAPK signaling pathway.