Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 58
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Biol Chem ; 299(6): 104814, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37178919

RESUMEN

Epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma (LUAD) patients often respond to EGFR tyrosine kinase inhibitors (TKIs) initially but eventually develop resistance to TKIs. The switch of EGFR downstream signaling from TKI-sensitive to TKI-insensitive is a critical mechanism-driving resistance to TKIs. Identification of potential therapies to target EGFR effectively is a potential strategy to treat TKI-resistant LUADs. In this study, we developed a small molecule diarylheptanoid 35d, a curcumin derivative, that effectively suppressed EGFR protein expression, killed multiple TKI-resistant LUAD cells in vitro, and suppressed tumor growth of EGFR-mutant LUAD xenografts with variant TKI-resistant mechanisms including EGFR C797S mutations in vivo. Mechanically, 35d triggers heat shock protein 70-mediated lysosomal pathway through transcriptional activation of several components in the pathway, such as HSPA1B, to induce EGFR protein degradation. Interestingly, higher HSPA1B expression in LUAD tumors associated with longer survival of EGFR-mutant, TKI-treated patients, suggesting the role of HSPA1B on retarding TKI resistance and providing a rationale for combining 35d with EGFR TKIs. Our data showed that combination of 35d significantly inhibits tumor reprogression on osimertinib and prolongs mice survival. Overall, our results suggest 35d as a promising lead compound to suppress EGFR expression and provide important insights into the development of combination therapies for TKI-resistant LUADs, which could have translational potential for the treatment of this deadly disease.


Asunto(s)
Adenocarcinoma del Pulmón , Diarilheptanoides , Resistencia a Antineoplásicos , Neoplasias Pulmonares , Animales , Humanos , Ratones , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Línea Celular Tumoral , Diarilheptanoides/farmacología , Receptores ErbB/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Lisosomas/metabolismo , Mutación , Inhibidores de Proteínas Quinasas/farmacología
2.
J Am Chem Soc ; 146(34): 24177-24187, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39140408

RESUMEN

Despite significant progress achieved in artificial self-sorting in solution, operating self-sorting in the body remains a considerable challenge. Here, we report an in vivo self-sorting peptide system via an in situ assembly evolution for combined cancer therapy. The peptide E3C16-SS-EIY consists of two disulfide-connected segments, E3C16SH and SHEIY, capable of independent assembly into twisted or flat nanoribbons. While E3C16-SS-EIY assembles into nanorods, exposure to glutathione (GSH) leads to the conversion of the peptide into E3C16SH and SHEIY, thus promoting in situ evolution from the nanorods into self-sorted nanoribbons. Furthermore, incorporation of two ligand moieties targeting antiapoptotic protein XIAP and organellar endoplasmic reticulum (ER) into the self-sorted nanoribbons allows for simultaneous inhibition of XIAP and accumulation surrounding ER. This leads to the cytotoxicity toward the cancer cells with elevated GSH levels, through activating caspase-dependent apoptosis and inducing ER dysfunction. In vivo self-sorting of E3C16-SS-EIY decorated with ligand moieties is thoroughly validated by tissue studies. Tumor-bearing mouse experiments confirm the therapeutic efficacy of the self-sorted assemblies for inhibiting tumor growth, with excellent biosafety. Our findings demonstrate an efficient approach to develop in vivo self-sorting systems and thereby facilitating in situ formulation of biomedical agents.


Asunto(s)
Péptidos , Humanos , Animales , Péptidos/química , Péptidos/farmacología , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Proteína Inhibidora de la Apoptosis Ligada a X/antagonistas & inhibidores , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo , Glutatión/química , Glutatión/metabolismo , Línea Celular Tumoral , Nanotubos/química
3.
J Am Chem Soc ; 146(31): 21348-21356, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-38905206

RESUMEN

Quantum dots (QDs) exhibit superior brightness and photochemical stability, making them the preferred option for highly sensitive single-molecule detection compared with fluorescent dyes or proteins. Nevertheless, their high surface energy leads to nonspecific adsorption and poor colloidal stability. In the past decades, we have found that QD-based fluorescent nanoparticles (FNs) can not only address these limitations but also enhance detection sensitivity. However, the photoluminescence quantum yield (PLQY) of FNs is significantly lower compared with that of original QDs. It is urgent to develop a strategy to solve the issue, aiming to further enhance detection sensitivity. In this study, we found that the decrease of PLQY of FNs prepared by free radical polymerization was attributed to two factors: (1) generation of defects that can cause nonradiative transitions resulting from QD-ligands desorption and QD-shell oxidation induced by free radicals; (2) self-absorption resulting from aggregation caused by incompatibility of QDs with polymers. Based on these, we proposed a multihierarchical regulation strategy that includes: (1) regulating QD-ligands; (2) precisely controlling free radical concentration; and (3) constructing cross-linked structures of polymer to improve compatibility and to reduce the formation of surface defects. It is crucial to emphasize that the simultaneous coordination of multiple factors is essential. Consequently, a world-record PLQY of 97.6% for FNs was achieved, breaking through the current bottleneck at 65%. The flexible application of this regulatory concept paves the way for the large-scale production of high-brightness QD-polymer complexes, enhancing their potential applications in sensitive biomedical detection.

4.
J Am Chem Soc ; 145(44): 24375-24385, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37883809

RESUMEN

Here, we develop a novel methodology for synthesizing chiral CdSe@ZnS quantum dots (QDs) with enhanced circularly polarized luminescence (CPL) by incorporating l-/d-histidine (l-/d-His) ligands during ZnS shell growth at the water/oil interface. The resulting chiral QDs exhibit exceptional absolute photoluminescence quantum yield of up to 67.2%, surpassing the reported limits of 40.0% for chiral inorganic QDs, along with absorption dissymmetry factor (|gabs|) and luminescence dissymmetry factor (|glum|) values of 10-2, exceeding the range of 10-5-10-3 and 10-4-10-2, respectively. Detailed investigations of the synthetic pathway reveal that the interface, as a binary synthetic environment, facilitates the coordinated ligand exchange and shell growth mediated by chiral His-Zn2+ coordination complexes, leading to a maximum fluorescent brightness and chiroptical activities. The growth process, regulated by the His-Zn2+ coordination complex, not only reduces trap states on the CdSe surface, thereby enhancing the fluorescence intensity, but also significantly promotes the orbital hybridization between QDs and chiral ligands, effectively overcoming the shielding effect of the wide bandgap shell and imparting pronounced chirality. The proposed growth pathway elucidates the origin of chirality and provides insights into the regulation of the CPL intensity in chiral QDs. Furthermore, the application of CPL QDs in multilevel anticounterfeiting systems overcomes the limitations of replication in achiral fluorescence materials and enhances the system's resistance to counterfeiting, thus opening new opportunities for chiral QDs in optical anticounterfeiting and intelligent information encryption.

5.
Anal Chem ; 95(42): 15540-15548, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37831785

RESUMEN

With the development of near-infrared II (NIR-II) fluorescence imaging, Ag2Se quantum dots (QDs) have become promising label candidates due to their negligible toxicity and narrow band gap. Despite their potential for gastrointestinal (GI) imaging, the application of Ag2Se QDs still presents significant challenges due to issues such as fluorescence extinction or poor stability in the complex digestive microenvironment. Herein, we have proposed a novel approach to the continuous production of Se precursors using glutathione (GSH) as the reductant under acidic conditions, realizing the continuous growth of water-dispersible Ag2Se QDs. The Ag2Se QDs emitting at 600-1100 nm have been successfully synthesized. Meanwhile, the silver-rich surface of the synthesized NIR-II Ag2Se QDs has been passivated well with the dense GSH, resulting in exceptional colloidal stability and photostability and endowing them with acid resistance. As a result, the obtained NIR-II Ag2Se QDs have exhibited remarkable stability in gastric acid, thus enabling their utilization for long-term real-time monitoring of GI peristalsis via NIR-II fluorescence imaging. Moreover, in contrast to conventional barium meal-based X-ray imaging, NIR-II fluorescence imaging with as-prepared NIR-II Ag2Se QDs can offer clearer visualization of fine intestinal structures, with a width as small as 1.07 mm. The developed strategy has offered a new opportunity for the synthesis of acid-resistant nanocrystals, and the acid-resistant, low-toxicity, and biocompatible NIR-II Ag2Se QDs synthesized in this work show a great promise for GI imaging and diagnosis of GI diseases in vivo.


Asunto(s)
Nanopartículas , Puntos Cuánticos , Puntos Cuánticos/toxicidad , Puntos Cuánticos/química , Nanopartículas/química , Fluorescencia , Plata/química
6.
Small ; 19(16): e2206272, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36683231

RESUMEN

The redox homeostasis in tumors enhances their antioxidant defense ability, limiting reactive oxygen species mediated tumor therapy efficacy. The development of strategies for specific and continuous disruption of the redox homeostasis in tumor cells facilitates the improvement of the cancer therapeutic effect by promoting the apoptosis of tumor cells. Herein, a responsively biodegradable targeting multifunctional integrated nanosphere (HDMn-QDs/PEG-FA) is designed to enhance the anti-tumor efficacy by triggering intratumoral cascade reactions to effectively disrupt intracellular redox homeostasis. Once HDMn-QDs/PEG-FA enters tumor cells, manganese dioxide (MnO2 ) shell on the surface of nanosphere consumes glutathione (GSH) to produce Mn2+ , enabling enhanced chemodynamic therapy (CDT) via a Fenton-like reaction and T1 -weighted magnetic resonance imaging. Meanwhile, the degradation of MnO2 can also cause the fluorescence recovery of quantum dots conjugated on the surface of the shell, realizing "turn-on" fluorescence imaging. In addition, the doxorubicin is released because of the cleavage of the embedded SS bond in the hybrid core framework by GSH. A superior synergistic therapeutic efficiency combined CDT and chemotherapy is shown by HDMn-QDs/PEG-FA in vivo. The tumor-inhibition rate reaches to 94.8% and does not cause normal tissue damage due to the good targeting and tumor microenvironment-specific response.


Asunto(s)
Nanopartículas , Nanosferas , Neoplasias , Humanos , Línea Celular Tumoral , Glutatión/química , Peróxido de Hidrógeno/metabolismo , Compuestos de Manganeso/química , Nanopartículas/química , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Oxidación-Reducción , Óxidos/química , Microambiente Tumoral
7.
J Chem Phys ; 159(6)2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37551805

RESUMEN

Clusters are considered to become increasingly significant for elaborating the nanocrystal's formation mechanism. However, capturing the clusters with high chemical potential is challenging because of the lack of effective strategies. In this work, the key role of ligand-solvent interaction has been revealed for the stabilization of clusters in silver telluride synthesis. The Flory interaction coefficient that comprehensively regards the temperature and dispersion, polarity, and hydrogen bonding of the solvent has been used to evaluate the ligand-solvent interaction and thus assist in the design of synthetic systems. Small silver telluride clusters have been successfully captured, and the composition of the smallest cluster is determined as Ag7Te8(SCy)2 (SCy represents the ligand). This work provides new insights into the design of cluster/nanocrystal synthesis systems and paves the way to revealing the mechanism of precursor-cluster-nanocrystal conversion.

8.
Traffic ; 21(1): 106-137, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31760668

RESUMEN

Many plasma membrane (PM) functions depend on the cholesterol concentration in the PM in strikingly nonlinear, cooperative ways: fully functional in the presence of physiological cholesterol levels (35~45 mol%), and nonfunctional below 25 mol% cholesterol; namely, still in the presence of high concentrations of cholesterol. This suggests the involvement of cholesterol-based complexes/domains formed cooperatively. In this review, by examining the results obtained by using fluorescent lipid analogs and avoiding the trap of circular logic, often found in the raft literature, we point out the fundamental similarities of liquid-ordered (Lo)-phase domains in giant unilamellar vesicles, Lo-phase-like domains formed at lower temperatures in giant PM vesicles, and detergent-resistant membranes: these domains are formed by cooperative interactions of cholesterol, saturated acyl chains, and unsaturated acyl chains, in the presence of >25 mol% cholesterol. The literature contains evidence, indicating that the domains formed by the same basic cooperative molecular interactions exist and play essential roles in signal transduction in the PM. Therefore, as a working definition, we propose that raft domains in the PM are liquid-like molecular complexes/domains formed by cooperative interactions of cholesterol with saturated acyl chains as well as unsaturated acyl chains, due to saturated acyl chains' weak multiple accommodating interactions with cholesterol and cholesterol's low miscibility with unsaturated acyl chains and TM proteins. Molecules move within raft domains and exchange with those in the bulk PM. We provide a logically established collection of fluorescent lipid probes that preferentially partition into raft and non-raft domains, as defined here, in the PM.


Asunto(s)
Colesterol , Microdominios de Membrana , Membrana Celular , Lípidos , Liposomas Unilamelares
9.
J Am Chem Soc ; 144(21): 9312-9323, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35587998

RESUMEN

Self-sorting is a common phenomenon in eukaryotic cells and represents one of the versatile strategies for the formation of advanced functional materials; however, developing artificial self-sorting assemblies within living cells remains challenging. Here, we report on the GSH-responsive in situ self-sorting peptide assemblies within cancer cells for simultaneous organelle targeting to promote combinatorial organelle dysfunction and thereby cell death. The self-sorting system was created via the design of two peptides E3C16E6 and EVMSeO derived from lipid-inspired peptide interdigitating amphiphiles and peptide bola-amphiphiles, respectively. The distinct organization patterns of the two peptides facilitate their GSH-induced self-sorting into isolated nanofibrils as a result of cleavage of disulfide-connected hydrophilic domains or reduction of selenoxide groups. The GSH-responsive in situ self-sorting in the peptide assemblies within HeLa cells was directly characterized by super-resolution structured illumination microscopy. Incorporation of the thiol and ER-targeting groups into the self-sorted assemblies endows their simultaneous targeting of endoplasmic reticulum and Golgi apparatus, thus leading to combinatorial organelle dysfunction and cell death. Our results demonstrate the establishment of the in situ self-sorting peptide assemblies within living cells, thus providing a unique platform for drug targeting delivery and an alternative strategy for modulating biological processes in the future.


Asunto(s)
Aparato de Golgi , Péptidos , Retículo Endoplásmico/metabolismo , Aparato de Golgi/metabolismo , Células HeLa , Humanos , Péptidos/química , Transporte de Proteínas
10.
Anal Chem ; 94(24): 8818-8826, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35686482

RESUMEN

Bacterial infectious diseases are common clinical diseases that seriously threaten human health, especially in countries and regions with poor environmental hygiene. Due to the lack of characteristic clinical symptoms and signs, it is a challenge to distinguish a bacterial infection from other infections, leading to misdiagnosis and antibiotic overuse. Therefore, there is an urgent need to develop a specific method for detection of bacterial infections. Herein, utilizing ultrabright fluorescent nanospheres (FNs) as reporters, immunochromatographic dyad test strips are developed for the early detection of bacterial infections and distinction of different stages of bacterial infectious diseases in clinical samples. C-reactive protein (CRP) and heparin-binding protein (HBP) are quantified and assayed because their levels in plasma are varied dynamically and asynchronously during the progression of the disease. The detection limits of CRP and HBP can reach as low as 0.51 and 0.65 ng/mL, respectively, due to the superior fluorescence intensity of each FN, which is 570 times stronger than that of a single quantum dot. The assay procedure can be achieved in 22 min, fully meeting the needs of rapid and ultrasensitive detection in the field. This constructed strip has been successfully used to profile the stage and severity of bacterial infections by monitoring the levels of CRP and HBP in human plasma samples, showing great potential as a point-of-care biosensor for clinical diagnosis. In addition to bacterial infections, the developed ultrabright FN-based point-of-care testing can be readily expanded for rapid, quantitative, and ultrasensitive detection of other trace substances in complex systems.


Asunto(s)
Infecciones Bacterianas , Técnicas Biosensibles , Enfermedades Transmisibles , Nanosferas , Puntos Cuánticos , Infecciones Bacterianas/diagnóstico , Técnicas Biosensibles/métodos , Proteína C-Reactiva/análisis , Humanos , Nanosferas/química , Puntos Cuánticos/química
11.
Chem Rev ; 120(3): 1936-1979, 2020 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-31951121

RESUMEN

Uncovering the mechanisms of virus infection and assembly is crucial for preventing the spread of viruses and treating viral disease. The technique of single-virus tracking (SVT), also known as single-virus tracing, allows one to follow individual viruses at different parts of their life cycle and thereby provides dynamic insights into fundamental processes of viruses occurring in live cells. SVT is typically based on fluorescence imaging and reveals insights into previously unreported infection mechanisms. In this review article, we provide the readers a broad overview of the SVT technique. We first summarize recent advances in SVT, from the choice of fluorescent labels and labeling strategies to imaging implementation and analytical methodologies. We then describe representative applications in detail to elucidate how SVT serves as a valuable tool in virological research. Finally, we present our perspectives regarding the future possibilities and challenges of SVT.


Asunto(s)
Virología/métodos , Virosis/virología , Animales , Humanos , Fenómenos Fisiológicos de los Virus
12.
Angew Chem Int Ed Engl ; 61(29): e202204518, 2022 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-35460326

RESUMEN

The formation of atherosclerotic plaques is the root cause of various cardiovascular diseases (CVDs). Effective CVD interventions thus call for precise identification of the plaques to aid clinical assessment, diagnosis, and treatment of such diseases. In this study, we introduce a dual-target sequentially activated fluorescence reporting system, termed in-sequence high-specificity dual-reporter unlocking (iSHERLOCK), to precisely identify the atherosclerotic plaques in vivo and ex vivo. ISHERLOCK was achieved by creating a three-in-one fluorescent probe that permits highly specific and sensitive detection of lipid droplets and hypochlorous acid via "off-on" and ratiometric readouts, respectively. Based on this format, the upregulated lipid accumulation and oxidative stress-the two hallmarks of atherosclerosis (AS)-were specifically measured in the atherosclerotic plaques, breaking through the barrier of precise tissue biopsy of AS and thus aiding effective CVD stewardship.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Aterosclerosis/diagnóstico por imagen , Fluorescencia , Colorantes Fluorescentes , Humanos , Placa Aterosclerótica/diagnóstico por imagen , Placa Aterosclerótica/patología
13.
J Am Chem Soc ; 143(32): 12867-12877, 2021 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-34353027

RESUMEN

Ag2Te is one of the most promising semiconductors with a narrow band gap and low toxicity; however, it remains a challenge to tune the emission of Ag2Te quantum dots (QDs) precisely and continuously in a wide range. Herein, Ag2Te QDs emitting from 950 to 2100 nm have been synthesized via trialkylphosphine-controlled growth. Trialkylphosphine has been found to induce the dissolution of small-sized Ag2Te QDs due to its stronger ability to coordinate to the Ag ion than that of 1-octanethiol, predicated by the density functional theory. By controlling this dissolution effect, the monomer supply kinetics can be regulated, achieving precise size control of Ag2Te QDs. This synthetic strategy results in state-of-the-art silver-based QDs with emission tunability. Only by taking advantage of such an ultrawide emission has the sizing curve of Ag2Te been obtained. Moreover, the absolute photoluminescence quantum yield of Ag2Te QDs can reach 12.0% due to their well-passivated Ag-enriched surface with a density of 5.0 ligands/nm2, facilitating noninvasive in vivo fluorescence imaging. The high brightness in the long-wavelength near-infrared (NIR) region makes the cerebral vasculature and the tiny vessel with a width of only 60 µm clearly discriminable. This work reveals a nonclassical growth mechanism of Ag2Te QDs, providing new insight into precisely controlling the size and corresponding photoluminescence properties of semiconductor nanocrystals. The ultrasmall, low-toxicity, emission-tunable, and bright NIR-II Ag2Te QDs synthesized in this work offer a tremendous promise for multicolor and deep-tissue in vivo fluorescence imaging.

14.
Nano Lett ; 19(11): 8002-8009, 2019 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-31626554

RESUMEN

Oncolytic adenovirus (OA) is an ideal candidate for clinical anticancer treatment, because it can specifically replicate in tumor cells with high titer. However, its systemic administration is still hindered, because of severely compromised antitumor efficacy. Herein, an engineered OA was innovatively developed by enwrapping OA with calcium and manganese carbonates (MnCaCs) biomineral shell, which could protect the virus from removal of the host immune system and prolong its in vivo circulation. Upon accumulating in tumor sites, MnCaCs readily dissolved under the acidic microenvironment, releasing Mn2+ that could convert endogenous H2O2 into oxygen (O2) and then enhance the duplication ability of OA, thus significantly increased the antitumor efficacy. Meanwhile, Mn2+ and the increased O2 individually endowed the T1 modal magnetic resonance imaging (MRI) and photoacoustic imaging (PAI) feasibility, providing real-time monitoring information for the therapy. This versatile engineered OA demonstrated its promise for visible and efficient oncolytic virotherapy by systemic administration.


Asunto(s)
Adenoviridae/química , Carbonato de Calcio/química , Carbonatos/química , Manganeso/química , Neoplasias/terapia , Viroterapia Oncolítica/métodos , Virus Oncolíticos/química , Adenoviridae/genética , Animales , Ingeniería Genética , Imagen por Resonancia Magnética , Ratones Endogámicos BALB C , Neoplasias/diagnóstico por imagen , Virus Oncolíticos/genética , Técnicas Fotoacústicas , Microambiente Tumoral
15.
Sensors (Basel) ; 18(8)2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30071646

RESUMEN

A fiber ring resonator (FRR) constructed using a Panda polarization-maintaining fiber does not effectively solve the problem of temperature-related polarization fluctuation, which considerably limits the detection accuracy of the resonant fiber optic gyro. The polarization-maintaining photonic crystal fiber (PM-PCF) can improve the thermal stability of the FRR. In this study, a structure that can simultaneously detect the polarization fluctuation of two FRRs is designed. We analyzed and verified the polarization phase shift errors of these two types of fibers, which are caused by the thermally induced birefringence changes. Theoretical simulation and experimental results confirm that a PM-PCF can be used to optimize the FRR, which can effectively suppress the polarization fluctuation.

16.
J Nanobiotechnology ; 15(1): 37, 2017 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-28477617

RESUMEN

BACKGROUND: Quantum dot (QD)-based single virus tracking has become a powerful tool for dissecting virus infection mechanism. However, only virus behaviors at the early stage of retrograde trafficking have been dynamically tracked so far. Monitoring of comprehensive virus retrograde transportation remains a challenge. RESULTS: Based on the superior fluorescence properties of QDs and their labeling of virus internal component, the dynamic interactions between baculoviruses and all key transportation-related cellular structures, including vesicles, acidic endosomes, actins, nuclear pores and nuclei, were visualized at the single-virus level. Detailed scenarios and dynamic information were provided for these critical interaction processes. CONCLUSIONS: A comprehensive model of baculovirus retrograde trafficking involving virus endocytosis, fusion with acidic endosome, translocation to nuclear periphery, internalization into nucleus, and arriving at the destination in nucleus was proposed. Thus the whole retrograde transportation of baculovirus in live host cells was elucidated at the single-virus level for the first time.


Asunto(s)
Baculoviridae/aislamiento & purificación , Baculoviridae/fisiología , Endosomas/virología , Colorantes Fluorescentes/análisis , Insectos/virología , Imagen Óptica , Puntos Cuánticos/análisis , Animales , Transporte Biológico , Línea Celular , Endocitosis , Fluorescencia , Microscopía Fluorescente , Internalización del Virus
17.
Hepatobiliary Pancreat Dis Int ; 16(5): 537-544, 2017 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-28992887

RESUMEN

BACKGROUND: Post-pancreaticoduodenectomy pancreatic fistula associated hemorrhage (PPFH) is one of the leading lethal complications. Our study was to analyze the risk factors and managements of hemorrhage associated with pancreatic fistula after pancreaticoduodenectomy, and to evaluate treatment options. METHOD: We analyzed 445 patients who underwent pancreaticoduodenectomy or pylorus-preserving pancreaticoduodenectomy and evaluated the relevance between clinical data and PPFH. RESULTS: The incidence of postoperative pancreatic fistula (POPF) was 27.42% (122/445), and the incidence of PPFH was 4.49% (20/445). Among the 20 patients with PPFH, 7 died and 13 were cured. Interventional angiographic therapy was performed for 10 patients and 5 were successfully treated. Relaparotomy was performed for 5 patients and 2 were successfully cured. Univariate logistic regression analysis indicated that several risk factors were related to PPFH: the nature of tumor (carcinoid/low-grade or high-grade malignancy), preoperative day 1 serum prealbumin, preoperative day 1 total bilirubin (TBIL), operative time, blood loss in the operation, operative method (vascular resection and revascularization), postoperative day 3 TBIL, biliary fistula, and the grade of POPF. The multivariate stepwise logistic regression analysis demonstrated that the nature of tumor and the grade of POPF were independently risk factors of PPFH. Receiver operating characteristic curve indicated that preoperative day 1 serum prealbumin level <173 mg/L and postoperative day 3 TBIL level ≥168 µmol/L were the risk factors of PPFH. CONCLUSIONS: The risk of PPFH was found to be increased with high potential malignancy and high grade of POPF. Angiography-embolization is one of the major and effective therapies for PPFH. Extraluminal-intraluminal PPFH is more serious and needs more aggressive treatments.


Asunto(s)
Hemorragia/etiología , Fístula Pancreática/complicaciones , Pancreaticoduodenectomía/efectos adversos , Adulto , Anciano , Embolización Terapéutica , Femenino , Hemorragia/terapia , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Prealbúmina/análisis , Factores de Riesgo
18.
Mol Cancer ; 14: 177, 2015 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-26438046

RESUMEN

BACKGROUND: Apoptosis-stimulating of p53 protein 2 (ASPP2) is one of the ASPP family members and it has been reported to be associated with human cancer. However, the role of it in pancreatic cancer is still not clear. METHODS: We analyzed the expression level of ASPP2 in cancer tissue samples with RT-qPCR, Western Blotting assay and immunohistochemistry staining. We studied the biological function of ASPP2 and its mechanism with gene overexpression and gene silencing technologies. We determined the sensitivity of pancreatic cells with differential ASPP2 level to gemcitabine and whether autophagy inhibition affected the gemcitabine resistance, both in vitro and in vivo. RESULTS: Expression of ASPP2 was downregulated in cancerous tissues in comparison with para-cancerous tissues. ASPP2 expression was linked to clinical outcomes in patients and down-regulation of ASPP2 increased cell proliferation, autophagic flux, the activity of AMP Kinase of pancreatic cancer cells and vice versa. Knockdown of ASPP2 results in increased resistance to gemcitabine, which was attributed to the enhanced autophagy. CONCLUSIONS: ASSP2 expression is lower in cancerous tissues and decreased ASPP2 lead to higher cancer cells proliferation and autophagic flux, which contribute to the gemcitabine resistance.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia/efectos de los fármacos , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamiento farmacológico , Adulto , Anciano , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Desoxicitidina/farmacología , Regulación hacia Abajo , Femenino , Humanos , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Neoplasias Pancreáticas/metabolismo , ARN Interferente Pequeño , Reacción en Cadena en Tiempo Real de la Polimerasa , Gemcitabina
19.
Biol Res ; 48: 23, 2015 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-25943891

RESUMEN

BACKGROUND: Hepcidin, encoding by HAMP gene, is the pivotal regulator of iron metabolism, controlling the systemic absorption and transportation of irons from intracellular stores. Abnormal levels of HAMP expression alter plasma iron parameters and lead to iron metabolism disorders. Therefore, it is an important goal to understand the mechanisms controlling HAMP gene expression. RESULTS: Overexpression of Sox2 decrease basal expression of HAMP or induced by IL-6 or BMP-2, whereas, knockdown of Sox2 can increase HAMP expression, furthermore, two potential Sox2-binding sites were identified within the human HAMP promoter. Indeed, luciferase experiments demonstrated that deletion of any Sox2-binding site impaired the negative regulation of Sox2 on HAMP promoter transcriptional activity in basal conditions. ChIP experiments showed that Sox2 could directly bind to these sites. Finally, we verified the role of Sox2 to negatively regulate HAMP expression in human primary hepatocytes. CONCLUSION: We found that Sox2 as a novel factor to bind with HAMP promoter to negatively regulate HAMP expression, which may be further implicated as a therapeutic option for the amelioration of HAMP-overexpression-related diseases, including iron deficiency anemia.


Asunto(s)
Regulación Neoplásica de la Expresión Génica/genética , Hepatocitos/metabolismo , Hepcidinas/genética , Factores de Transcripción SOXB1/genética , Anemia/genética , Anemia/metabolismo , Sitios de Unión , Proteína Morfogenética Ósea 2/metabolismo , Técnicas de Silenciamiento del Gen , Vectores Genéticos , Células Hep G2 , Hepcidinas/metabolismo , Humanos , Interleucina-6/metabolismo , Hierro/metabolismo , Luciferasas , Plásmidos/genética , Regiones Promotoras Genéticas/genética , Factores de Transcripción SOXB1/metabolismo
20.
Adv Healthc Mater ; : e2401836, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39015050

RESUMEN

Nanozymes, with their versatile composition and structural adaptability, present distinct advantages over natural enzymes including heightened stability, customizable catalytic activity, cost-effectiveness, and simplified synthesis process, making them as promising alternatives in various applications. Recent advancements in nanozyme research have shifted focus from serendipitous discovery toward a more systematic approach, leveraging machine learning, theoretical calculations, and mechanistic explorations to engineer nanomaterial structures with tailored catalytic functions. Despite its pivotal role, electron transfer, a fundamental process in catalysis, has often been overlooked in previous reviews. This review comprehensively summarizes recent strategies for modulating electron transfer processes to fine-tune the catalytic activity and specificity of nanozymes, including electron-hole separation and carrier transfer. Furthermore, the bioapplications of these engineered nanozymes, including antimicrobial treatments, cancer therapy, and biosensing are also introduced. Ultimately, this review aims to offer invaluable insights for the design and synthesis of nanozymes with enhanced performance, thereby advancing the field of nanozyme research.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA