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1.
Biomater Adv ; 151: 213477, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37244029

RESUMO

Intelligent drug-delivery systems are considered one of the most important techniques for improving cancer treatment using existing over-the-counter medicines. However, metallic materials are always accompanied by metabolism problems, whereas chemotherapy produces several side effects in humans. Carbon-based materials exhibit exceptional features such as bio-affinity and bio-degradability. Herein, hollow mesoporous carbon nanoparticles (HMCs) are reported as effective nanocarriers of anti-cancer small drug molecules. Near IR (NIR) sources, which can penetrate most organs, induce thermal effects via non-invasive pathways. NIR radiation not only provides thermal therapy but also is compatible with temperature-sensitive coated responsive polymer shells. The template method was used to synthesize HMCs with size 200 ± 50 nm, under various conditions, to obtain suitably sized and hollow structures for liver-cancer treatment. Additional pH/thermal-bi-responsive poly(N-isopropylacrylamide) (PNIPAM) shells were further coated onto the HMCs to produce multiple shells that could trigger swelling motions in PNIPAM@HMCs, as confirmed via small-angle X-ray scattering (SAXS). NIR results demonstrated an extreme increase to the ∆T of 8.7 and 14.2 °C for HMC and PNIPAM@HMCs, respectively. The SAXS spectra analyzed using SasView simulations demonstrated the multi-shell structures of synthesized HMCs and the release mechanism of PNIPAM@HMCs. Based on the model simulation of SAXS, the different rates of polymer swelling indicated the core shrinkage (229.7 to 134.2 Å) and shell expansion (324.3 to 514.3 Å) at 37 °C and 42 °C, respectively. In addition, the first-order, Higuchi, Korsmeyer-Peppas, and Weibull mathematical models were used to verify the drug-release kinetics, and the model with the highest R2 value was considered most suitable for further application. This paper presents the first SAXS study on PNIPAM@HMCs release kinetics and related mechanisms. This phenomenon indicates NIR-induced PNIPAM@HMCs as an effective strategy for cancer treatment via doxorubicin release.


Assuntos
Antineoplásicos , Nanopartículas , Humanos , Carbono/química , Liberação Controlada de Fármacos , Nanopartículas/química , Espalhamento a Baixo Ângulo , Difração de Raios X , Polímeros , Concentração de Íons de Hidrogênio
2.
Zool Stud ; 62: e7, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37223434

RESUMO

The family Fulgoridae belongs to the order Hemiptera, superfamily Fulgoridea, with approximately 770 described species worldwide. Their extraordinary appearance attracts the attention of both entomologists and the public. In addition to the evolutionary issue of their special appearance, certain species are also considered notorious pests (e.g., Lycorma delicatula). Several issues widely exist in previous taxonomic studies of lanternflies: (1) application of uncertain morphological characters leads to synonymy or misidentification; (2) descriptions of male genitalia are incomplete; (3) information of nymphal morphology is insufficient. Therefore, this study aims to provide a comprehensive taxonomic study of Fulgoridae from Taiwan. In this study, eight species in six genera from Taiwan were reported, of which Limois westwoodii was recorded for the first time from Taiwan. Lycorma olivacea was proposed as a new junior synonym of L. meliae. The fifth-instar nymph of Saiva formosana was described for the first time. Detailed descriptions of these lanternflies and an identification key to adults of Fulgoridae from Taiwan were also included.

3.
J Exp Med ; 220(8)2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37158982

RESUMO

Type I interferons are important antiviral cytokines, but prolonged interferon production is detrimental to the host. The TLR3-driven immune response is crucial for mammalian antiviral immunity, and its intracellular localization determines induction of type I interferons; however, the mechanism terminating TLR3 signaling remains obscure. Here, we show that the E3 ubiquitin ligase ZNRF1 controls TLR3 sorting into multivesicular bodies/lysosomes to terminate signaling and type I interferon production. Mechanistically, c-Src kinase activated by TLR3 engagement phosphorylates ZNRF1 at tyrosine 103, which mediates K63-linked ubiquitination of TLR3 at lysine 813 and promotes TLR3 lysosomal trafficking and degradation. ZNRF1-deficient mice and cells are resistant to infection by encephalomyocarditis virus and SARS-CoV-2 because of enhanced type I interferon production. However, Znrf1-/- mice have exacerbated lung barrier damage triggered by antiviral immunity, leading to enhanced susceptibility to respiratory bacterial superinfections. Our study highlights the c-Src-ZNRF1 axis as a negative feedback mechanism controlling TLR3 trafficking and the termination of TLR3 signaling.


Assuntos
COVID-19 , Interferon Tipo I , Animais , Camundongos , Antivirais , SARS-CoV-2 , Receptor 3 Toll-Like , Genes src
4.
Pharmaceutics ; 15(3)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36986601

RESUMO

Nanomedicine has garnered significant interest owing to advances in drug delivery, effectively demonstrated in the treatment of certain diseases. Here, smart supermagnetic nanocomposites based on iron oxide nanoparticles (MNPs) coated with Pluronic F127 (F127) were developed for the delivery of doxorubicin (DOX) to tumor tissues. The XRD patterns for all samples revealed peaks consistent with Fe3O4, as shown by their indices (220), (311), (400), (422), (511), and (440), demonstrating that the structure of Fe3O4 did not change after the coating process. After loading with DOX, the as-prepared smart nanocomposites demonstrated drug-loading efficiency and drug-loading capacity percentages of 45 ± 0.10 and 17 ± 0.58% for MNP-F127-2-DOX and 65 ± 0.12 and 13 ± 0.79% for MNP-F127-3-DOX, respectively. Moreover, a better DOX release rate was observed under acidic conditions, which may be credited to the pH sensitivity of the polymer. In vitro analysis demonstrated the survival rate of approximately 90% in HepG2 cells treated with PBS and MNP-F127-3 nanocomposites. Furthermore, after treatment with MNP-F127-3-DOX, the survival rate decreased, confirming cellular inhibition. Hence, the synthesized smart nanocomposites showed great promise for drug delivery in liver cancer treatment, overcoming the limitations of traditional therapies.

5.
Colloids Surf B Biointerfaces ; 222: 113129, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36610364

RESUMO

A new drug delivery system (DDS) type complexing magnetic nanoparticles (MNP) along with boron nanosheets (BNN) coated with a pH-responsive polymer-polyethylene glycol (PEG) for the manageable loading/release of the anti-cancerous drug, doxorubicin (DOX), was created (MNP-BNN-PEG-DOX). The X-ray diffraction patterns of the nanocomposites displayed wide diffraction peaks for BNN at 25.1° and 42.3°, belonging to the (002) and (100) planes, correspondingly. Additionally, the characteristic peaks of Fe3O4 appeared at 30.5°, 35.9°, 43.6°, 54.1°, 57.5°, and 63.2°, belonging to the (220), (311), (400), (422), (511), and (440) crystal planes, correspondingly. Moreover, the magnetic properties of the nanocomposites revealed that the MNP-BNN remained magnetic after coating with PEG. The saturation magnetization (Ms) of the uncoated-MNP-BNN and MNP-BNN-PEG-1 were 49.4 and 42.3 emu g-1, respectively. Both in vitro and in vivo analyses shown that DDS might inhibit tumor growth, provoke cancer cell apoptosis, and reduce the cytotoxic effects of DOX. In vivo analysis demonstrated that after treatment with phosphate-buffered saline (PBS), MNP-BNN-PEG-1, free DOX, and MNP-BNN-PEG-1-DOX, the average tumor growth and weight were 1906, 1997, 1188, and 1043 nm and 0.17, 0.20, 0.13, and 0.07 g, respectively. The MNP-BNN-PEG-DOX nanoparticles could be an effective treatment and potential alternative for liver cancer therapy.


Assuntos
Antineoplásicos , Neoplasias Hepáticas , Humanos , Doxorrubicina , Antineoplásicos/química , Sistemas de Liberação de Medicamentos , Neoplasias Hepáticas/tratamento farmacológico , Polietilenoglicóis/química , Concentração de Íons de Hidrogênio , Fenômenos Magnéticos , Portadores de Fármacos/química
6.
Int J Biol Macromol ; 228: 487-497, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36581030

RESUMO

Dual pH-sensitive smart nanocarriers based on silica nanoparticles (SNPs) extracted from rice husk ashes (RHAs) to effectively inhibit liver cancer cell proliferation were investigated. The SNPs were coated with chitosan (CH) and loaded with doxorubicin (DOX), then functionalized with cell membrane (CM) for homologous targeting ability. The FTIR spectra showed an absorption wave number at 1083 cm-1 which confirmed the existence of the SiOSi group, ratifying that the nanocarriers belong to silica species. The Korsmeyer-Peppas kinetic model reported R2 values of 0.996 and 0.931 for pH = 5.4 and pH = 7.4, respectively, demonstrating pH-responsive behavior of the nanocarriers. The cytotoxicity test confirmed that the HepG2 cell line treated with different SNP-CH-CM concentrations had no detectable significant cell toxicity, however, SNP-CH-DOX-CM induced greater cell death. In vivo tests revealed that SNP-CH-DOX-CM suppressed liver cancer growth in nude mice, demonstrating high pharmaceutical capability. Histological examination of vital organs showed that the targeted drug delivery system (DDS) had minor in vivo toxicity. In the light of its high treatment efficacy and minimal side effects, the investigated DDS is promising for the therapy of liver cancer.


Assuntos
Carcinoma Hepatocelular , Quitosana , Neoplasias Hepáticas , Nanopartículas , Oryza , Animais , Camundongos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Quitosana/química , Carcinoma Hepatocelular/tratamento farmacológico , Dióxido de Silício/química , Camundongos Nus , Sistemas de Liberação de Medicamentos , Doxorrubicina , Membrana Celular , Nanopartículas/química , Concentração de Íons de Hidrogênio , Portadores de Fármacos/química
7.
Colloids Surf B Biointerfaces ; 220: 112923, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36252536

RESUMO

In recent years, nanoscience has attracted considerable attention in the field of biomedicine. This involves the use of engineered nanomaterials as vital platforms for targeted drug delivery, diagnosis, imaging, and observation of therapeutic efficiency. This study explored the preparation, characterization, and applications of doxorubicin-loaded magnetic rice husk ash-derived SBA-15 (MIO@RHAS15-DOX nanocomposites) for drug delivery and in vitro/in vivo efficiency in the treatment of liver cancer. The small-angle XRD patterns of the MIO@RHAS15 nanocomposites demonstrated a core diffraction peak at 0.94°, with two noticeable peaks at 1.6° and 1.8°, representing (100), (110), and (200) crystalline planes, respectively, thereby indicating the existence of a well-defined mesostructure. A sharp melting endothermic peak (Tm) at 79 °C was observed for MIO@RHAS15 nanocomposites. The DOX release from MIO@RHAS15 followed the Higuchi model with the best correlation coefficient R2 value of 0.9799. The in vitro studies indicated a concentration dependent anticancer efficiency, with high cancer cells inhibition for MIO@RHAS15-DOX than free DOX. At the highest concentration of DOX (120 µg/mL), there was less than 25% and 15% cell viability after 24 h and 48 h, respectively. The in vivo studies demonstrated that the tumor sizes after treatment with PBS, MIO@RHAS15, free DOX, and MIO@RHS15-DOX were 1081, 904, 143, and 167 mm3, respectively. The in vivo animal test results depicted that the MIO@RHAS15-DOX nanocomposites were able to inhibit liver tumors in all tested mice. Therefore, the prepared nanocomposites possess a great potential for drug delivery application towards cancer treatment, thereby overcoming the limitations of traditional chemotherapy.


Assuntos
Antineoplásicos , Neoplasias Hepáticas , Nanocompostos , Oryza , Camundongos , Animais , Doxorrubicina , Nanocompostos/química , Neoplasias Hepáticas/tratamento farmacológico , Fenômenos Magnéticos
8.
Biomater Adv ; 140: 213070, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35961189

RESUMO

Microporous round cake-like (diameter: 900 ± 100 nm) MIL-125(Ti) carrier with a central metal (Ti) exhibiting bio-affinity and possessing a great potential to be used as drug release platform, has been synthesized in the present study. The thermal and pH responsiveness of drug delivery systems (DDS) are the most important parameters for drug release and can be provided through polymer coating techniques. The Pluronic F127 (F127) and chitosan (CH) monomers were inserted into the crystal lattice of MIL-125(Ti) carrier during the de novo synthesis process, which were subsequently loaded with doxorubicin (DOX). The results reveal particle size changes (ranged between 30 and 50 %) from the original size of the MIL-125(Ti) carrier in response to temperature and pH when the carrier reaches acid environment. The drug release profiles have been completed through self-design device, which provides for the real-time release in the DOX amounts via UV-Vis spectra. The kinetics analysis was used to evaluate the R2 values of first order, Higuchi, Korsmeyer-peppas, and Weibull fitting equations, where the Weibull fitting indicated the best R2. An increase by 59.3 % of DOX released under the acid status (pH = 5.4) was observed, indicating that the CH-MIL-125(Ti) carrier is temperature and pH responsive. Moreover, the lattice explosion resulting from the temperature increase in the range of 25-42 °C caused an increase in F127-MIL-125(Ti) by 30.8-38.3 %. The simulated SAXS/WAXS studies for the microstructures of MIL-125(Ti) based DDS at different temperatures after polymer coating (F127-MIL-125(Ti)) provide the possible mechanism of lattice explosion. As such, the responsive Ti-MOF has a highly potential for use in the applications of cancer treatment.


Assuntos
Quitosana , Titânio , Quitosana/química , Doxorrubicina/química , Liberação Controlada de Fármacos , Excipientes , Concentração de Íons de Hidrogênio , Polímeros/química , Espalhamento a Baixo Ângulo , Titânio/química , Difração de Raios X
9.
Colloids Surf B Biointerfaces ; 209(Pt 2): 112168, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34715504

RESUMO

The upsurge in cancer cases, such as liver cancer, has claimed millions of lives globally and has prompted the development of novel nanodrug delivery systems. These systems allow cancer drugs to be encapsulated in nanocarriers and delivered to tumor sites, and accordingly, help reduce side effects of the current chemotherapeutic treatments. Herein, we prepared nanocarriers comprising magnetic iron oxide (MIO) nanoparticles that were surface modified with crosslinked Pluronic F127 (PF127) and branched polyethylenimine (bPEI) to form MIOpoly nanocarriers. These nanocarriers were then loaded with doxorubicin (DOX) anticancer drug to form the MIOpoly-DOX complex. The nanocarriers were magnetite and possessed superparamagnetic properties. Small-angle neutron scattering (SANS) analysis indicated that the nanocarriers were thermoresponsive and spherically structured. The characteristic peaks at 1285, 1619, 2844, 2919, 2900, 2840, and 3426 cm-1, corresponding to those of CN, -NH2, -CH2, and OH-, confirmed the successful crosslinking, coating of PF127-bPEI polymers on the surface of MIO nanoparticles and DOX conjugation. The bioavailability of the nanocarriers indicated a more than 85% cell viability when using HepG2 liver cancer cells. A pH (54.8% release in 48 h; pH = 5.4) and temperature (51.0% release in 48 h; 42 °C)-dependent release of DOX was observed, displaying a Korsmeyer-Peppas kinetics model at low pH and Weibull model at high temperatures. The high DOX fluorescence observed for MIOpoly-DOX indicated a high cellular uptake enhanced by alternating magnetic field. These results suggest that MIOpoly synthesized using a combined approach of surface crosslinking and grafted with PF127-bPEI appear to offer promising properties as drug delivery system. Therefore, the nanocarriers developed in the study possess a great potential for targeted delivery and thereby circumventing the limitations of conventional chemotherapy.


Assuntos
Antineoplásicos , Nanopartículas , Antineoplásicos/farmacologia , Doxorrubicina , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Campos Magnéticos
10.
Biology (Basel) ; 10(7)2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34356533

RESUMO

The longan lanternfly Pyrops candelaria is a new invasive species on the main island of Taiwan. The introduction of an invasive species may negatively influence the native fauna, flora and environment. Thus, this study aimed to infer the invasion history, predict habitat suitability and potential expansion and assess the risk to crop cultivation areas in Taiwan. Genetic structures of P. candelaria from the main island of Taiwan and related regions were analyzed based on partial COI and ND2 sequences. Additionally, machine learning MaxEnt was utilized to study habitat suitability. The results suggested that the Taiwanese populations may originate from the Kinmen Islands and the plain areas of Taiwan are considered to have high habitat suitability. Furthermore, most of the cultivation areas of longan and pomelo crops showed high habitat suitability.

11.
Front Cell Dev Biol ; 9: 642625, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996800

RESUMO

Activation of the epidermal growth factor receptor (EGFR) is crucial for development, tissue homeostasis, and immunity. Dysregulation of EGFR signaling is associated with numerous diseases. EGFR ubiquitination and endosomal trafficking are key events that regulate the termination of EGFR signaling, but their underlying mechanisms remain obscure. Here, we reveal that ZNRF1, an E3 ubiquitin ligase, controls ligand-induced EGFR signaling via mediating receptor ubiquitination. Deletion of ZNRF1 inhibits endosome-to-lysosome sorting of EGFR, resulting in delayed receptor degradation and prolonged downstream signaling. We further demonstrate that ZNRF1 and Casitas B-lineage lymphoma (CBL), another E3 ubiquitin ligase responsible for EGFR ubiquitination, mediate ubiquitination at distinct lysine residues on EGFR. Furthermore, loss of ZNRF1 results in increased susceptibility to herpes simplex virus 1 (HSV-1) infection due to enhanced EGFR-dependent viral entry. Our findings identify ZNRF1 as a novel regulator of EGFR signaling, which together with CBL controls ligand-induced EGFR ubiquitination and lysosomal trafficking.

12.
J Pediatr Surg ; 56(7): 1227-1232, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33838896

RESUMO

BACKGROUND: Patients with neuroblastoma, a common childhood malignancy, often have poor prognosis. It is mandatory to develop an accurate and efficient diagnostic tool for neuroblastomas, so that the treatment can be started early. Graphene quantum dot (GQD), a nanomaterial, can be used to carry proteins, genetic materials, or drugs. GD2, a disialoganglioside, is a surface antigen expressed on neuroblastoma. This study investigated the in vivo targeting and imaging of neuroblastomas using GD2-targeting GQDs. METHODS: GQDs were synthesized and conjugated with anti-GD2 antibody (anti-GD2/GQDs). In vitro cytotoxicity of GQDs and anti-GD2/GQDs was studied in human neuroblastoma cells by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide)-based colorimetric assay. The tumor tracking and imaging of anti-GD2/GQDs in mice were investigated by in vivo imaging system (IVIS). RESULTS: Treatment with GQDs or anti-GD2/GQDs induced no or mild cytotoxicity in fibroblasts and neuroblastoma cells. After co-incubation, GQDs and anti-GD2/GQDs were located in the cytoplasm and nucleus of neuroblastoma cells, with GQDs showing a blue fluorescence and anti-GD2/GQDs an orange/red emission. The IVIS images demonstrated accumulation of the fluorescence of anti-GD2/GQDs in the subcutaneous tumors in mice 24 h after intravenous injection of anti-GD2/GQDs. CONCLUSIONS: Anti-GD2/GQDs may potentially be used for the targeting and imaging of neuroblastomas in vivo.


Assuntos
Grafite , Neuroblastoma , Pontos Quânticos , Animais , Criança , Diagnóstico por Imagem , Humanos , Camundongos , Neuroblastoma/diagnóstico por imagem
13.
J Hazard Mater ; 407: 124879, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33387972

RESUMO

The present study was conducted to determine the Cd distribution and speciation in contaminated paddy soils and rice kernels using XANES/EXAFS spectroscopy. The morphology and crystallization of rice and soils were investigated using FE-SEM and XRD techniques. The EXAFS spectra of Cd in soil and rice kernels showed that cadmium oxides (CdO) in soil and rice kernels formed Cd clusters with Cd-O bond distances of 2.35 Å and 2.25 Å (coordination numbers of 2.3 and 3.8), respectively. The XRD patterns show that silica oxide (SiO2, 2θ = 24.2) and aluminum oxide (Al2O3, 2θ = 35.7) were the main components detected. The FE-SEM analysis revealed that the surface characteristics and sizes of the rice kernels are smooth and uneven with particle sizes of 0.5-4 µm, while the soil particles are not uniform and aggregated. Furthermore, the distribution of toxic metals/metalloid (Cd, Pb, Cr, Ni, As, Cu, and Zn) accumulated in the contaminated paddy soils and rice crops were also examined. Interestingly, these results offered an insight into the accumulation mechanism and distribution of heavy metals in contaminated rice farming soils and rice crops.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Cádmio/análise , Metais Pesados/análise , Dióxido de Silício , Solo , Poluentes do Solo/análise
14.
Theranostics ; 10(20): 9200-9213, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32802187

RESUMO

Rationale: Autophagy is an essential, homeostatic process by which cells break down their own components, it also contributes to restricting bacterial infection in host defense systems; yet, how autophagy regulates viral infection remains inconclusive. Aichi virus (AiV), belonging to the genus Kobuvirus in the Picornaviridae family, causes acute gastroenteritis in human. The role of autophagy-mediated anti-viral activity on AiV infection was investigated in this study. Methods: The effect of autophagy-associated molecules in retinoic acid-inducible gene-I (RIG-I)-like receptor (RLR) antiviral signal axis was analyzed in AiV infected cells by using biochemistry and pharmacologic approaches. In addition, the AiV viral protein regulating autophagy-associated RLR activity was also evaluated. Results: In AiV-infected cells, autophagic flux including the formation of autophagic vacuoles, as well as degradation of microtubule-associated protein light chain 3 (LC3) and sequestosome-1 (SQSTM1/p62) were observed. Ectopic overexpression of LC3 and p62, but not Atg proteins, contributed to RLR antiviral signal axis, shRNA knockdown of LC3 and p62 led to a downregulation of antiviral inflammation. Moreover, AiV infection inhibited double-stranded RNA (dsRNA)-activated RLR activity by the viral protein 3C protease but not H42D, C143S protease dead mutants. AiV 3C protease caused the degradation of LC3 and p62, and also RLR signal proteins. Conclusion: This study reveals a possible mechanism of autophagy-associated proteins regulating virus replication. Maintaining a cellular level of LC3 and p62 during the viral infection period might help restrict virus replication. Although, AiV 3C protease dampens the LC3 and p62-mediated host antiviral machinery for AiV replication. Results obtained provide a better understanding of the molecular pathogenesis of AiV for developing methods of prevention and treatment.


Assuntos
Proteases Virais 3C/metabolismo , Antivirais/metabolismo , Kobuvirus/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteína Sequestossoma-1/metabolismo , Proteínas Virais/metabolismo , Células A549 , Animais , Autofagia/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Chlorocebus aethiops , Regulação para Baixo/fisiologia , Células HEK293 , Humanos , Células Vero , Replicação Viral/fisiologia
15.
J Hazard Mater ; 383: 121167, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31585329

RESUMO

The present study was conducted to determine the Cd distribution and speciation in contaminated paddy soils and rice kernels using XANES/EXAFS spectroscopy. The morphology and crystallization of rice and soils were investigated using FE-SEM and XRD techniques. The EXAFS spectra of Cd in soil and rice kernels showed that cadmium oxides (CdO) in soil and rice kernels formed Cd clusters with Cd-O bond distances of 2.35 Šand 2.83 Š(coordination numbers of 2.3 and 4.2), respectively. The XRD patterns show that silica oxide (SiO2, 2θ  = 24.2) and aluminum oxide (Al2O3, 2θ = 35.7) were the main components detected. The FE-SEM analysis revealed that the surface characteristics and sizes of the rice kernels are smooth and uneven with particle sizes of 0.5-4 µm, while the soil particles are not uniform and aggregated. Furthermore, the distribution of toxic metals/metalloid (Cd, Pb, Cr, Ni, As, Cu, and Zn) accumulated in the contaminated paddy soils and rice crops were also examined. Interestingly, these results offered an insight into the accumulation mechanism and distribution of heavy metals in contaminated rice farming soils and rice crops.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Cádmio/análise , Metais Pesados/análise , Dióxido de Silício , Solo , Poluentes do Solo/análise
16.
Neural Regen Res ; 13(9): 1585-1593, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30127119

RESUMO

Integrity of the blood-brain barrier structure is essential for maintaining the internal environment of the brain. Development of cerebral infarction and brain edema is strongly associated with blood-brain barrier leakage. Therefore, studies have suggested that protecting the blood-brain barrier may be an effective method for treating acute stroke. To examine this possibility, stroke model rats were established by middle cerebral artery occlusion and reperfusion. Remote ischemic postconditioning was immediately induced by three cycles of 10-minute ischemia/10-minute reperfusion of bilateral hind limbs at the beginning of middle cerebral artery occlusion reperfusion. Neurological function of rat models was evaluated using Zea Longa's method. Permeability of the blood-brain barrier was assessed by Evans blue leakage. Infarct volume and brain edema were evaluated using 2,3,5-triphenyltetrazolium chloride staining. Expression of matrix metalloproteinase-9 and claudin-5 mRNA was determined by real-time quantitative reverse transcription-polymerase chain reaction. Expression of matrix metalloproteinase-9 and claudin-5 protein was measured by western blot assay. The number of matrix metalloproteinase-9- and claudin-5-positive cells was analyzed using immunohistochemistry. Our results showed that remote ischemic postconditioning alleviated disruption of the blood-brain barrier, reduced infarct volume and edema, decreased expression of matrix metalloproteinase-9 mRNA and protein and the number of positive cells, increased expression of claudin-5 mRNA and protein and the number of positive cells, and remarkably improved neurological function. These findings confirm that by suppressing expression of matrix metalloproteinase-9 and claudin-5 induced by acute ischemia/reperfusion, remote ischemic postconditioning reduces blood-brain barrier injury, mitigates ischemic injury, and exerts protective effects on the brain.

17.
PeerJ ; 5: e3448, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28607841

RESUMO

Dengue virus types 1-4 (DENV-1-4) are positive-strand RNA viruses with an envelope that belongs to the Flaviviridae. DENV infection threatens human health worldwide. However, other than supportive treatments, no specific therapy is available for the infection. In order to discover novel medicine against DENV, we tested 59 crude extracts, without cytotoxicity, from 23 plants in vitro; immunofluorescence assay revealed that the methanol extracts of fruit, heartwood, leaves and stem from Ficus septica Burm. f. had a promising anti-DENV-1 and DENV-2 effect. However, infection with the non-envelope picornavirus, Aichi virus, was not inhibited by treatment with F. septica extracts. F. septica may be a candidate antiviral drug against an enveloped virus such as DENV.

18.
Nat Commun ; 8: 15502, 2017 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-28593998

RESUMO

Caveolin-1 (CAV1), the major constituent of caveolae, plays a pivotal role in various cellular biological functions, including cancer and inflammation. The ubiquitin/proteasomal pathway is known to contribute to the regulation of CAV1 expression, but the ubiquitin ligase responsible for CAV1 protein stability remains unidentified. Here we reveal that E3 ubiquitin ligase ZNRF1 modulates CAV1 protein stability to regulate Toll-like receptor (TLR) 4-triggered immune responses. We demonstrate that ZNRF1 physically interacts with CAV1 in response to lipopolysaccharide and mediates ubiquitination and degradation of CAV1. The ZNRF1-CAV1 axis regulates Akt-GSK3ß activity upon TLR4 activation, resulting in enhanced production of pro-inflammatory cytokines and inhibition of anti-inflammatory cytokine IL-10. Mice with deletion of ZNRF1 in their hematopoietic cells display increased resistance to endotoxic and polymicrobial septic shock due to attenuated inflammation. Our study defines ZNRF1 as a regulator of TLR4-induced inflammatory responses and reveals another mechanism for the regulation of TLR4 signalling through CAV1.


Assuntos
Caveolina 1/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Proteólise , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Sequência de Aminoácidos , Animais , Caveolina 1/química , Ceco/patologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Deleção de Genes , Glicogênio Sintase Quinase 3 beta/metabolismo , Mediadores da Inflamação/metabolismo , Ligadura , Lipopolissacarídeos , Lisina/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Punções , Células RAW 264.7 , Choque Séptico/imunologia , Choque Séptico/metabolismo , Choque Séptico/patologia , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Ubiquitina-Proteína Ligases/deficiência
19.
Tumour Biol ; 37(4): 4665-78, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26508031

RESUMO

Esculetin (6,7-dihydroxycoumarin), a derivative of coumarin compound, is found in traditional medicinal herbs. It has been shown that esculetin triggers diverse cellular signal transduction pathways leading to regulation of physiology in different models. However, whether esculetin affects Ca(2+) homeostasis in breast cancer cells has not been explored. This study examined the underlying mechanism of cytotoxicity induced by esculetin and established the relationship between Ca(2+) signaling and cytotoxicity in human breast cancer cells. The results showed that esculetin induced concentration-dependent rises in the intracellular Ca(2+) concentration ([Ca(2+)]i) in ZR-75-1 (but not in MCF-7 and MDA-MB-231) human breast cancer cells. In ZR-75-1 cells, this Ca(2+) signal response was reduced by removing extracellular Ca(2+) and was inhibited by the store-operated Ca(2+) channel blocker 2-aminoethoxydiphenyl borate (2-APB). In Ca(2+)-free medium, pre-treatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin (TG) abolished esculetin-induced [Ca(2+)]i rises. Conversely, incubation with esculetin abolished TG-induced [Ca(2+)]i rises. Esculetin induced cytotoxicity that involved apoptosis, as supported by the reduction of mitochondrial membrane potential and the release of cytochrome c and the proteolytic activation of caspase-9/caspase-3, which were partially reversed by pre-chelating cytosolic Ca(2+) with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA-AM). Moreover, esculetin increased the percentage of cells in G2/M phase and regulated the expressions of p53, p21, CDK1, and cyclin B1. Together, in ZR-75-1 cells, esculetin induced [Ca(2+)]i rises by releasing Ca(2+) from the ER and causing Ca(2+) influx through 2-APB-sensitive store-operated Ca(2+) entry. Furthermore, esculetin activated Ca(2+)-associated mitochondrial apoptotic pathways that involved G2/M cell cycle arrest. Graphical abstract The summary of esculetin-evoked [Ca(2+)]i rises and -activated Ca(2+)-associated mitochondrial apoptotic pathways that involved cell cycle arrest. The natural coumarin derivative esculetin caused Ca(2+) influx via 2-APB-sensitive store-operated Ca(2+) entry and induced Ca(2+) release from the endoplasmic reticulum. Moreover, esculetin activated the mitochondrial pathway of apoptosis in a Ca(2+)-associated manner that involved G2/M arrest.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Umbeliferonas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Cálcio , Sinalização do Cálcio , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular , Humanos , Concentração Inibidora 50 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias
20.
PLoS One ; 10(2): e0116158, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25646764

RESUMO

Human parechoviruses (HPeVs), members of the family Picornaviridae, are associated with severe human clinical conditions such as gastrointestinal disease, encephalitis, meningitis, respiratory disease and neonatal sepsis. A new contemporary strain of HPeV1, KVP6 (accession no. KC769584), was isolated from a clinical specimen. Full-genome alignment revealed that HPeV1 KVP6 shares high genome homology with the German strain of HPeV1, 7555312 (accession no. FM178558) and could be classified in the clade 1B group. An intertypic recombination was shown within the P2-P3 genome regions of HPeV1. Cell-type tropism test showed that T84 cells (colon carcinoma cells), A549 cells (lung carcinoma cells) and DBTRG-5MG cells (glioblastoma cells) were susceptible to HPeV1 infection, which might be relevant clinically. A facilitated cytopathic effect and increased viral titers were reached after serial viral passages in Vero cells, with viral genome mutation found in later passages. HPeV1 is sensitive to elevated temperature because 39C incubation impaired virion production. HPeV1 induced innate immunity with phosphorylation of interferon (IFN) regulatory transcription factor 3 and production of type I IFN in A549 but not T84 cells. Furthermore, type I IFN inhibited HPeV1 production in A549 cells but not T84 cells; T84 cells may be less responsive to type I IFN stimulation. Moreover, HPeV1-infected cells showed downregulated type I IFN activation, which indicated a type I IFN evasion mechanism. The characterization of the complete genome and infection features of HPeV1 provide comprehensive information about this newly isolated HPeV1 for further diagnosis, prevention or treatment strategies.


Assuntos
Antivirais/farmacologia , Genoma Viral/genética , Interferon Tipo I/farmacologia , Parechovirus/genética , Parechovirus/fisiologia , Infecções por Picornaviridae , Animais , Antivirais/metabolismo , Linhagem Celular , Genômica , Humanos , Interferon Tipo I/metabolismo , Cinética , Dados de Sequência Molecular , Parechovirus/efeitos dos fármacos , Transdução de Sinais , Temperatura , Tropismo Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
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