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1.
J Exerc Sci Fit ; 22(4): 297-304, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38706951

RESUMO

Background: Probiotic supplementation has a positive effect on endurance exercise performance and body composition in athletes, but the underlying mechanisms remain unclear. Gut microbiota can provide measurable markers of immune function in athletes, and microbial composition analysis may be sensitive enough to detect stress and metabolic disorders caused by exercise. Methods: Nineteen healthy active amateur marathon runners (15 male and 4 female) with a mean age of 29.11 years volunteered to participate in this double-blind controlled study. Based on the performance of the Cooper 12-min running test (CRT), the participants were allocated into two groups to receive either a probiotic formulation comprising lactobacillus acidophilus and bifidobacterium longum (n = 10) or placebo containing maltodextrin (n = 9) for five weeks. Consistency of diet and exercise was ensured throughout the experimental period. Before and after the intervention, all participants were assessed for CRT, emotional stability and gastrointestinal symptoms, gut microbiota composition, body composition and magnetic resonance imaging (MRI) indicators of skeletal muscle microcirculation. Results: Compared to before the intervention, the probiotics group showed an increase in CRT score (2.88 ± 0.57 vs 3.01 ± 0.60 km, P<0.05), significant improvement in GSRS and GIQLI (9.20 ± 4.64 vs 7.40 ± 3.24, 118.90 ± 12.30 vs 127.50 ± 9.85, P<0.05), while these indicators remained unchanged in the control group, with a significant time-group interaction effect on gastrointestinal symptoms. Additionally, some MRI metabolic cycling indicators of the thigh skeletal muscle also changed in the probiotics group (P<0.05). Regarding microbiota abundance, the probiotics group exhibited a significant increase in the abundance of beneficial bacteria and a significant decrease in the abundance of harmful bacteria post-intervention (P<0.05). Conclusion: As a sports nutritional supplement, probiotics have the potential to improve athletic performance by optimizing the balance of gut microbiota, alleviating gastrointestinal symptoms.

2.
Zhongguo Zhong Yao Za Zhi ; 49(1): 123-129, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38403345

RESUMO

This study explored the preparation process of the placebo of Jiawei Ermiao Granules and evaluated the placebo effect, aiming to provide qualified placebo samples for clinical trials of Jiawei Ermiao Granules and a reference for the preparation and quality evaluation of placebos of traditional Chinese medicine granules. On the basis of the comprehensive analysis results of Jiawei Ermiao Granules, the orthogonal experiment was conducted to optimize the flavoring agents and colorants. After manual evaluation, the placebo formula was determined as dextrin 10 g, Codonopsis Radix extract 5.0 g, bitter melon extract 1.6 g, Mume Fructus extract 0.3 g, stevioside 0.1 g, sucrose octaacetate 0.004 g, indigo 0.004 g, lemon yellow 0.003 1 g, sunset yellow 0.001 8 g, bitter tea powder 0.001 8 g, caramel 0.001 3 g. Pilot trials were conducted on the placebo formula. The simulation effect of placebo was evaluated independently and comparatively, and the objectively evaluated by electronic nose and electronic tongue. The results showed that the independent manual evaluation of the placebo formula had higher error rate, and the placebo and Jiawei Ermiao Granules showed the similarity of 99.61% in the comparative manual evaluation. The smell similarity between the placebo and Jiawei Ermiao Granules was 99.19%, and the electronic tongue test showed little difference in the taste. In conclusion, the placebo prepared in this study shows a high similarity to Jiawei Ermiao Granules, which is not easy to break the blindness when being applied to clinical trials. This study provides a reference for the preparation and quality evaluation and promotes the large-scale production of placebos of traditional Chinese medicine granules, playing a role in improving the persuasiveness and acceptance of the efficacy of traditional Chinese medicines.


Assuntos
Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Paladar
3.
ESC Heart Fail ; 11(2): 1009-1021, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38234046

RESUMO

AIMS: Myocardial ischaemia-reperfusion injury (MIRI) contributes to serious myocardial injury and even death. Long non-coding RNAs (lncRNAs) have been reported to play pivotal roles in the occurrence and development of MIRI. Here, the detailed molecular mechanism of lncRNA SNHG1 in MIRI was explored. METHODS AND RESULTS: A cell model of MIRI was established through hypoxia/reoxygenation (H/R) stimulation. Cell viability and pyroptosis were evaluated utilizing MTT, PI staining, and flow cytometry. Interleukin (IL)-1ß and IL-18 secretion levels were examined by ELISA. The gene and protein expression were detected by RT-qPCR and western blot, respectively. Dual luciferase reporter gene, RIP and ChIP assays were performed to analyse the molecular interactions. The results showed that lncRNA SNHG1 overexpression alleviated H/R-induced HL-1 cell pyroptosis (all P < 0.05). LncRNA SNHG1 promoted KLF4 expression by sponging miR-137-3p. miR-137-3p silencing alleviated H/R-induced pyroptosis in HL-1 cells (all P < 0.05), which was abolished by KLF4 knockdown (all P < 0.05). KLF4 activated the AKT pathway by transcriptionally activating TRPV1 in HL-1 cells (all P < 0.05). TRPV1 knockdown reversed the alleviation of SNHG1 upregulation on H/R-induced pyroptosis in HL-1 cells (all P < 0.05). CONCLUSIONS: These results showed that lncRNA SNHG1 assuaged cardiomyocyte pyroptosis during MIRI progression by regulating the KLF4/TRPV1/AKT axis through sponging miR-137-3p. Our findings may provide novel therapeutic targets for MIRI.


Assuntos
MicroRNAs , Traumatismo por Reperfusão Miocárdica , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Traumatismo por Reperfusão Miocárdica/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , MicroRNAs/genética , Miocárdio/metabolismo , Hipóxia , Canais de Cátion TRPV
4.
Microbiol Spectr ; 11(3): e0073323, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37154775

RESUMO

As the α-subunit of the high-affinity receptor for the Fc portion of immunoglobulin E (FcεRIα), FcεRIα plays a central role in IgE-mediated allergic disorders and in the immunity and immunopathology of some parasitic infections. FcεRIα is specifically expressed on basophils and mast cells, but the mechanism that controls FcεRIα expression in these cells is poorly understood. In this study, we found that the natural antisense transcript (NAT) of FcεRIα (FCER1A-AS) is co-expressed with the sense transcript (FCER1A-S) in both interleukin (IL)-3-induced FcεRIα-expressing cells and in the high FcεRIα-expressing cell line MC/9. When FCER1A-AS is selectively knocked down by the CRISPR/RfxCas13d (CasRx) approach in MC/9 cells, the expression of both FCER1A-S mRNA and proteins is markedly decreased. Furthermore, FCER1A-AS deficiency was also found to be associated with a lack of FCER1A-S expression in vivo. Correspondingly, homozygous mice deficient in FCER1A-AS demonstrated a similar phenotype to FCER1A knockout mice in Schistosoma japonicum infection and in IgE-FcεRIα-mediated cutaneous anaphylaxis. Thus, we uncovered a novel pathway for the control of FcεRIα expression by its co-expressed natural antisense transcript. IMPORTANCE FcεRIα is responsible for high-affinity binding with the Fc portion of IgE, which is critical for IgE-dependent disease responses such as allergy responses and anti-parasite immunity. FcεRIα is expressed on a few cell types, including mast cells and basophils. Although the expression of FcεRIα is known to be promoted by the IL-3-GATA-2 pathway during its differentiation, the mechanism by which FcεRIα expression is maintained remains unknown. In this study, we discovered that a natural antisense transcript, FCER1A-AS, is co-expressed with the sense transcript. The presence of FCER1A-AS is essential for sense transcript expression in mast cells and basophils, but not for the differentiation of these cells through cis-regulation. Like FcεRIα knockout mice, mice lacking FCER1A-AS also exhibit reduced survival after Schistosoma japonicum infection and a lack of IgE-mediated cutaneous anaphylaxis. Thus, a novel pathway for regulating IgE-mediated allergic diseases through noncoding RNAs has been revealed.


Assuntos
Anafilaxia , RNA Antissenso , Receptores de IgE , Esquistossomose Japônica , Animais , Camundongos , Imunoglobulina E , Camundongos Knockout , Receptores de IgE/genética , Receptores de IgE/metabolismo , RNA Antissenso/genética , RNA Antissenso/metabolismo
5.
Appl Radiat Isot ; 189: 110446, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36099746

RESUMO

High energy over MeV bremsstrahlung sources that employ normal conducting radio frequency linear accelerators have expanding applications in industrial computerized tomography (CT) for non-destructive inspection and evaluation. The X-ray spot size that mainly affects the imaging quality is yet limited by the electron beam width in the high resolution CT systems. In a short exposure time, high beam power is required to generate sufficient photons to improve the signal to noise ratio of imaging. However, with ∼kW level of average beam power these linear accelerators usually have a beam spot size over 1 mm since the temperature rising due to the beam energy deposition in the target should be far below its melting point. We propose a concept of using a Rhodotron-based accelerator to provide high power electron beams in a long duration pulse and a rotating target to mitigate the overheating issue, such that the gap between micro-spot and high dose rate can be bridged in the high energy bremsstrahlung sources. This article presents an in-depth simulation work to discuss and evaluate this scheme of X-ray source. The simulations of beam dynamics in the accelerator and bremsstrahlung process in the target predict the generated X-rays with a spot size as small as 68 µm at full-width half-maximum and a dose rate as high as 4700 cGy/min from a 9 MeV electron beam interacting with a 1 mm thickness tantalum target. Further thermal analysis in the rotating target indicates a significant improvement of beam power handling in comparison with the conventional stationary one.

6.
Biomed Mater Eng ; 33(1): 65-76, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34366316

RESUMO

BACKGROUND: Cartilage tissue lacks the ability to heal. Cartilage tissue engineering using cell-free scaffolds has been increasingly used in recent years. OBJECTIVE: This study describes the use of a type I collagen scaffold combined with WNT5A plasmid to promote chondrocyte proliferation and differentiation in a rabbit osteochondral defect model. METHODS: Type I collagen was extracted and fabricated into a collagen scaffold. To improve gene transfection efficiency, a cationic chitosan derivative N,N,N-trimethyl chitosan chloride (TMC) vector was used. A solution of TMC/WNT5A complexes was adsorbed to the collagen scaffold to prepare a WNT5A scaffold. Osteochondral defects were created in the femoral condyles of rabbits. The rabbits were divided into defect, scaffold, and scaffold with WNT5A groups. At 6 and 12 weeks after creation of the osteochondral defects, samples were collected from all groups for macroscopic observation and gene expression analysis. RESULTS: Samples from the defect group exhibited incomplete cartilage repair, while those from the scaffold and scaffold with WNT5A groups exhibited "preliminary cartilage" covering the defect. Cartilage regeneration was superior in the scaffold with WNT5A group compared to the scaffold group. Safranin O staining revealed more proteoglycans in the scaffold and scaffold with WNT5A groups compared to the defect group. The expression levels of aggrecan, collagen type II, and SOX9 genes were significantly higher in the scaffold with WNT5A group compared to the other two groups. CONCLUSIONS: Type I collagen scaffold showed effective adsorption and guided the three-dimensional arrangement of stem cells. WNT5A plasmid promoted cartilage repair by stimulating the expression of aggrecan, type II collagen, and SOX9 genes and proteins, as well as inhibiting cartilage hypertrophy.


Assuntos
Cartilagem Articular , Engenharia Tecidual , Animais , Colágeno Tipo I , Plasmídeos , Coelhos , Alicerces Teciduais
7.
Rev Sci Instrum ; 92(1): 014705, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33514231

RESUMO

Wideband RF cavity beam position monitors (CBPM) have been increasingly employed for short bunch interval operations in several linear accelerators. At a few nanoseconds of bunch spacing, the loaded quality factor of the CBPM TM110 dipole eigenmode is required to be sufficiently low to minimize the signal interference between consecutive bunches. Moreover, the bunched beam also couples to several unwanted higher-order modes (HOM), such as the TM210 and TE111 eigenmodes, which also may result in an error of the bunch position measurement if no precautions are taken. In the fabrication phase of CBPMs, the mode coupling can alter the TM110 mode frequency and therefore causes an error in its tuning, e.g., 0.3% for a 4.875 GHz CBPM with QL = 22.5. This error needs to be identified so that the precise tuning is enabled since the dipole mode frequency becomes critical for the position evaluations as the signal processing is relatively phase-sensitive. This paper presents an approach to extract the pure unperturbed frequency of the dipole mode, not altered by the response to coupled HOMs. An analytic model based on the superposition law applied to electromagnetic fields has been developed to characterize the response of coupled HOMs in the S-parameter measurement. The model has been further verified with numerical simulation in the CST-Studio software by analyzing an approximate single-mode response CBPM. The correction method was applied on a wideband CBPM prototype for the pre-research plan of future high repetition rate hard XFEL at the Chinese Academy of Engineering Physics.

8.
Neuroreport ; 31(18): 1308-1314, 2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33165197

RESUMO

The role of norepinephrine of the hippocampal dentate gyrus in spatial learning and memory alteration induced by chronic restraint stress (CRS, 3 h/day, 6 weeks) was investigated in aged rats. Spatial learning and memory were assessed by the Morris water maze (MWM), and the extracellular concentration of norepinephrine and amplitude of field excitatory postsynaptic potential (fEPSP) were measured in the dentate gyrus during MWM test in freely-moving rats. Next, the involvement of ß-adrenoceptors in spatial learning and memory of CRS rats was examined by microinjection of its antagonist (propranolol) into the dentate gyrus. In addition, we observed the expression of brain-derived neurotrophic factor (BDNF) protein and activation of cAMP-response element binding protein (CREB) in the dentate gyrus. Compared with the control group, the basal level of norepinephrine, BDNF expression and CREB activation in the dentate gyrus were increased, and the spatial learning and memory abilities were enhanced in CRS rats. In the control group, the norepinephrine concentration and fEPSP amplitude in the dentate gyrus were increased on the second to fourth days of MWM test, and these responses were significantly enhanced in CRS rats. Furthermore, in CRS rats, propranolol significantly decreased the spatial learning and memory abilities, and attenuated the fEPSP response during MWM test, and the BDNF expression and CREB activation in the dentate gyrus. Our results suggest that norepinephrine activation of ß-adrenoceptors in the hippocampal dentate gyrus is involved in spatial learning and memory enhancement induced by CRS in aged rats, in part via modulations of synaptic efficiency and CREB-BDNF signaling pathway.


Assuntos
Giro Denteado/metabolismo , Potenciais Pós-Sinápticos Excitadores/fisiologia , Norepinefrina/metabolismo , Restrição Física , Aprendizagem Espacial/fisiologia , Memória Espacial/fisiologia , Estresse Psicológico/metabolismo , Antagonistas Adrenérgicos beta/farmacologia , Animais , Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Giro Denteado/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Camundongos , Teste do Labirinto Aquático de Morris , Propranolol/farmacologia , Ratos , Aprendizagem Espacial/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Estresse Psicológico/fisiopatologia
9.
Chin J Traumatol ; 23(6): 314-318, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32847694

RESUMO

In this paper, we review the results of previous studies and summarize the effects of various factors on the regulation of bone metabolism in traumatic bone infections. Infection-related bone destruction incorporates pathogens and iatrogenic factors in the process of bone resorption dominated by the skeletal and immune systems. The development of bone immunology has established a bridge of communication between the skeletal system and the immune system. Exploring the effects of pathogens, skeletal systems, immune systems, and antibacterials on bone repair in infectious conditions can help improve the treatment of these diseases.


Assuntos
Osso e Ossos/lesões , Osso e Ossos/metabolismo , Sistema Imunitário/imunologia , Osteíte/metabolismo , Osteíte/microbiologia , Infecções Estafilocócicas , Antibacterianos/administração & dosagem , Osso e Ossos/imunologia , Microambiente Celular , Humanos , Subpopulações de Linfócitos/imunologia , Osteíte/tratamento farmacológico , Osteíte/imunologia , Osteoblastos/fisiologia , Osteoclastos/fisiologia
10.
Regen Med ; 15(6): 1735-1747, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32811280

RESUMO

Aim: We aimed to evaluate the capacity of the bilayer polylactic-co-glycolic acid (PLGA)/TGF-ß3/adipose-derived mesenchymal stem cell (ADSC) construct used to repair cartilage defects and the role of ADSCs in the repair process in vivo. Materials & methods: Defects were created surgically on the femoropatellar groove of knee joints in 64 rabbits. All the rabbits were randomly divided into four groups: defect group, PLGA group, PLGA/TGF-ß3 group and PLGA/TGF-ß3/ADSC group. In vivo MRI and Prussian blue staining were applied. Quantitative real-time PCR and western blot methods were used to analyze the gene and protein expression. Results & conclusion: The result showed that TGF-ß3 could effectively stimulate the expressions of aggrecan, collagen type II and SRY-related HMG box 9 (SOX9). The bilayer PLGA/TGF-ß3/ADSC construct showed a promising repair effect.


Assuntos
Doenças das Cartilagens/terapia , Cartilagem Articular/fisiologia , Nanopartículas Magnéticas de Óxido de Ferro/química , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Fator de Crescimento Transformador beta3/metabolismo , Animais , Cartilagem Articular/lesões , Diferenciação Celular , Células Cultivadas , Bicamadas Lipídicas/química , Coelhos , Engenharia Tecidual , Alicerces Teciduais/química , Fator de Crescimento Transformador beta3/química
11.
Bioorg Chem ; 92: 103186, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31465967

RESUMO

Kidney-type glutaminase (KGA), catalyzing the hydrolysis of glutamine to glutamate for energy supply, is over-expressed in many cancers and has been regarded as a new therapeutic target for cancers. Physapubescin I was isolated from the fruits of the edible herb Physalis pubescens L., commonly named as "husk tomato or hairy groundcherry", and was predicted to be a potential KGA inhibitor through structure-based virtual ligand screening. Enzyme inhibition assays, microscale thermophoresis (MST) and cellular thermal shift assay (CETSA) experiments have demonstrated the high efficiency and specificity of physapubescin I targeting KGA. EdU proliferation, Hoechst 33258 staining and cytotoxicity assays indicated that physapubescin I could inhibit cancer cell proliferation and promote apoptosis more effectively than the known KGA inhibitor, BPTES. Knockdown of KGA by siRNA reduced the inhibition of physapubescin I to SW1990 cells. Meanwhile, physapubescin I impaired glutamine metabolism in SW1990 cells with increasing intracellular level of glutamine, and correspondingly decreasing glutamate and its downstream metabolites, which may account for its inhibition of cancer cell proliferation and proapoptosis. Physapubescin I also showed significant tumor growth inhibition and low toxicity in a SW1990 xenograft mouse model. Collectively, physapubescin I may serve as a potential drug candidate or lead compound for cancer therapy by targeting KGA.


Assuntos
Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/química , Glutaminase/antagonistas & inibidores , Solanum lycopersicum/química , Vitanolídeos/química , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Sítios de Ligação , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/farmacologia , Escherichia coli , Glutaminase/genética , Glutamina/metabolismo , Xenoenxertos/efeitos dos fármacos , Humanos , Rim/metabolismo , Ligantes , Masculino , Camundongos , Camundongos SCID , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Vitanolídeos/farmacologia
12.
ISA Trans ; 86: 181-191, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30409439

RESUMO

With increasing penetration of variable loads and intermittent distributed energy resources (DERs) with uncertainty and variability in distribution systems, the power system gradually inherits some features (e.g., lack of rotating inertia), which leads to the voltage instability in microgrids. As a means to provide stability support for smart grid against high penetration of intermittent DERs, inverter-based smart loads across the distribution grid has been suggested recently. Accordingly, this paper presents a delay-tolerant distributed voltage control scheme based on consensus protocol for multiple-cooperative smart loads through effective demand-side management in ac microgrids, in which the time-delay effect on transmission communication occurred in information exchanges is considered. The proposed distributed voltage control scheme always enables the output voltage of each smart load to be synchronized to their reference value, which improves the robustness of system stability against transmission communication delays. The Lyapunov-Krasovskii functions are employed to analyze the stability of our proposed distributed control scheme, then the delay-independent stability conditions are derived, which allows some large communication delays. Moreover, the sensitivity analysis is developed to show how the time delay affects system dynamics in order to validate the robustness of proposed delay-independent stability conditions. Furthermore, a sparse communication network is employed to implement the proposed distributed control protocols, which thus satisfies the plug-and-play requirement of smart microgrids. Finally, the simulation results of an ac microgrid in MATLAB/SimPowerSystems are presented to demonstrate the effectiveness of the proposed control methodology.

13.
Immunology ; 149(2): 238-51, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27315109

RESUMO

Aluminium hydroxide (alum), the most widely used adjuvant in human and animal vaccines, has long been known to promote T helper type 2 (Th2) responses and Th2-associated humoral responses, but the mechanisms have remained poorly understood. In this study, we explored whether alum is able to directly modulate antigen-presenting cells to enhance their potency for Th2 polarization. We found that alum treatment of dendritic cells failed to show any Th2-promoting activities. In contrast, alum was able to enhance the capacity of basophils to induce Th2 cells. When basophils from interleukin-4 (IL-4) knockout mice were examined, the intrinsic Th2-promoting activities by basophils were largely abrogated, but the alum-enhanced Th2-promoting activities on basophils were still detectable. More importantly, Th2-promoting adjuvant activities by alum found in IL-4 knockout mice were also largely reduced when basophils were depleted by antibody administration. Therefore, basophils can mediate Th2-promoting activities by alum both in vitro and in vivo through IL-4-independent mechanisms. Further studies revealed that secreted soluble molecules from alum-treated basophils were able to confer the Th2-promoting activities, and neutralization of thymic stromal lymphopoietin or IL-25 attenuated the IL-4-independent development of Th2 cells elicited by alum-treated basophils. Finally, alum was able to activate NACHT, LRR and PYD domains-containing protein 3 (NLRP3) inflammasome in murine basophils in the same way as alum in professional antigen-presenting cells, but NLRP3 was not required for Th2-promoting activities on basophils by alum in vitro. These results demonstrated that alum can enhance the capacities of basophils to polarize Th2 cells via IL-4- and NLRP3-independent pathways.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Compostos de Alúmen/administração & dosagem , Basófilos/imunologia , Células Dendríticas/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Células Th2/imunologia , Vacinas/imunologia , Animais , Apresentação de Antígeno , Diferenciação Celular , Células Cultivadas , Humanos , Inflamassomos/metabolismo , Interleucina-4/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout
14.
Biomaterials ; 32(34): 9059-67, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21880365

RESUMO

In vitro or in vivo bioimaging utilizing the upconversion (UC) luminescence of rare earth fluoride nanocrystals (NCs) has attracted much attention, especially for Yb(3+)/Tm(3+) doped NCs with a near-infrared (NIR) UC emission at 800 nm. Herein, water-soluble NaYF(4):Yb,Tm NCs with strong NIR UC emission were synthesized with a solvothermal method. In vitro and in vivo bioimaging and toxicity assessments were carried out with HeLa cell and Caenorhabditis elegans (C. elegans) cases, respectively. NaYF(4):Yb,Tm NCs afforded an efficient NIR image of the HeLa cells with an incubation concentration of 10 µg mL(-1), and CCK-8 assay revealed a low cytotoxicity. Fed with Escherichia coli (E. coli) and NCs together, the C. elegans showed a NIR image in the gut from the pharynx to the anus. Further, these NCs could be excreted out when those worms were then fed with only E. coli. Toxicity studies were further addressed with protein expression, life span, egg production, egg viability, and growth rate of the worms in comparison with those of the intact ones. The feeding of rare earth fluoride NCs with a dose of 100 µg does not arise obvious toxicity effect from the growth to procreation. The in vitro and in vivo studies confirm that NaYF(4):Yb,Tm NCs could be served as an excellent NIR emission bioprobe with low toxicity.


Assuntos
Fluoretos/análise , Nanopartículas/análise , Nanopartículas/toxicidade , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Túlio/análise , Itérbio/análise , Ítrio/análise , Animais , Caenorhabditis elegans/ultraestrutura , Sobrevivência Celular , Fluoretos/química , Fluoretos/toxicidade , Células HeLa , Humanos , Substâncias Luminescentes/análise , Substâncias Luminescentes/química , Substâncias Luminescentes/toxicidade , Nanopartículas/química , Nanopartículas/ultraestrutura , Túlio/química , Túlio/toxicidade , Itérbio/química , Itérbio/toxicidade , Ítrio/química , Ítrio/toxicidade
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