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1.
J Nanobiotechnology ; 22(1): 123, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38504272

RESUMO

BACKGROUND: Photodynamic therapy (PDT) efficacy of bismuth sulfide (Bi2S3) semiconductor has been severely restricted by its electron-hole pairs (e--h+) separation inefficiency and oxygen (O2) deficiency in tumors, which greatly hinders reactive oxygen species (ROS) generation and further clinical application of Bi2S3 nanoparticles (NPs) in biomedicine. RESULTS: Herein, novel Bi2S3/titanium carbide (Ti3C2) two-dimensional nano-heterostructures (NHs) are designed to realize multimode PDT of synchronous O2 self-supply and ROS generation combined with highly efficient photothermal tumor elimination for hypoxic tumor therapy. Bi2S3/Ti3C2 NHs were synthesized via the in situ synthesis method starting from Ti3C2 nanosheets (NSs), a classical type of MXene nanostructure. Compared to simple Bi2S3 NPs, Bi2S3/Ti3C2 NHs significantly extend the absorption to the near-infrared (NIR) region and enhance the photocatalytic activity owing to the improved photogenerated carrier separation, where the hole on the valence band (VB) of Bi2S3 can react with water to supply O2 for the electron on the Ti3C2 NSs to generate ·O2- and ·OH through electron transfer. Furthermore, they also achieve 1O2 generation through energy transfer due to O2 self-supply. After the modification of triphenylphosphium bromide (TPP) on Bi2S3/Ti3C2 NHs, systematic in vitro and in vivo evaluations were conducted, revealing that the synergistic-therapeutic outcome of this nanoplatform enables complete eradication of the U251 tumors without recurrence by NIR laser irradiation, and it can be used for computed tomography (CT) imaging because of the strong X-ray attenuation ability. CONCLUSION: This work expands the phototherapeutic effect of Bi2S3-based nanoplatforms, providing a new strategy for hypoxic tumor theranostics.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Brometos/uso terapêutico , Terapia Fototérmica , Espécies Reativas de Oxigênio , Titânio/farmacologia , Neoplasias/tratamento farmacológico , Oxigênio , Hipóxia/tratamento farmacológico , Raios Infravermelhos , Linhagem Celular Tumoral
2.
Food Chem X ; 21: 101141, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38304045

RESUMO

Aroma is a key criterion in evaluating aromatic coconut water. A comparison regarding key aroma compounds and sensory correlations was made between Thailand Aromatic Green Dwarf (THD) and Cocos nucifera L. cv. Wenye No. 4 coconut water using E-nose and GC × GC-O-TOF-MS combined with chemometrics. Twenty-one volatile components of coconut water were identified by GC × GC-O-TOF-MS, and 5 key aroma compounds were analyzed by relative odor activity value and aroma extract dilution analysis. Moreover, the combination of the E-nose with orthogonal partial least squares was highly effective in discriminating between the two coconut water samples and screened the key sensors responsible for this differentiation. Additionally, the correlation between volatile compounds and sensory properties was established using partial least squares. The key aroma compounds of coconut water exhibited positive correlations with the corresponding sensory properties.

3.
Macromol Biosci ; 24(2): e2300282, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37580865

RESUMO

Antibacterial hydrogel has emerged as an excellent candidate for wound dressing with the ability to eliminate infection and promote wound healing. Herein, a dynamic hydrogel is developed by Schiff base reaction of mixed charged polypeptides and oxidized dextran (ODex). Specifically, biodegradable polypeptides of 1-(propylthio)acetic acid-3-butylimidazole-modified poly(L-lysine) (PLL-PBIM) and adipate dihydrazide-modified poly(L-glutamic acid) (PLG-ADH) are achieved with tunable substitution and charge. By mixing with ODex, charged polypeptides of PLL-PBIM and PLG-ADH led to an injectable and self-healing hydrogel in seconds. The injectable and self-healing performances of the hydrogels are ascribed to the reversible imine and hydrazone bonds formed between polypeptides and ODex. The positively charged hydrogels exhibited over 95% antibacterial activity against E. coli and S. aureus. An optimized balancing of PLG-ADH and PLL-PBIM significantly reduced the hemolysis rate and cytotoxicity of hydrogels. Therefore, the dynamic hydrogel with excellent biocompatibility and inherently antibacterial ability can have potential application for wound dressing.


Assuntos
Adesivos , Hidrogéis , Hidrogéis/farmacologia , Hidrogéis/química , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química , Bandagens , Peptídeos
4.
Front Genet ; 13: 895200, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812755

RESUMO

Background: Immune-related long non-coding RNAs (irlncRNAs) might remodel the tumor immune microenvironment by changing the inherent properties of tumor cells and the expression of immune genes, which have been used to predict the efficacy of immunotherapy and the prognosis of various tumors. However, the value of irlncRNAs in breast cancer (BRCA) remains unclear. Materials and Methods: Initially, transcriptome data and immune-related gene sets were downloaded from The Cancer Genome Atlas (TCGA) database. The irlncRNAs were extracted from the Immunology Database and Analysis Portal (ImmPort) database. Differently expressed irlncRNAs (DEirlncRNAs) were further identified by utilizing the limma R package. Then, univariate and multivariate Cox regression analyses were conducted to select the DEirlncRNAs associated with the prognosis of BRCA patients. In addition, the univariate and least absolute shrinkage and selection operator (LASSO) Cox regression analyses were performed to determine the DEirlncRNA pairs with the independent prediction capability of prognosis in BRCA patients. Finally, the chosen DEirlncRNA pair would be evaluated in terms of survival time, clinicopathological characteristics, tumor-infiltrating immune cells, immune checkpoints (ICs), signaling pathways, and potential small-molecule drugs. Results: A total of 21 DEirlncRNA pairs were extracted, and among them, lncRNA MIR4435-2HG and lncRNA U62317.1 were chosen to establish a risk signature that served as an independent prognostic biomarker in BRCA patients. Patients in the high-risk group had a worse prognosis than those in the low-risk group, and they also had an abundance of infiltration of CD4+ T and CD8+ T cells to enhance the immune response to tumor cells. Furthermore, the risk signature showed a strong correlation with ICs, signaling pathways, and potential small-molecule drugs. Conclusion: Our research revealed that the risk signature independent of specific DEirlncRNA pair expression was closely associated with the prognosis and tumor immune microenvironment in BRCA patients and had the potential to function as an independent prognostic biomarker and a predictor of immunotherapy for BRCA patients, which would provide new insights for BRCA accurate treatment.

5.
Opt Express ; 29(20): 31010-31025, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615203

RESUMO

Topological photonics is a hot topic in recent years. We combine it with the quantum optics and explore the dynamics of two quantum dots (QDs) separated by the finite coupled-cavity arrays (CCAs). The finite CCAs possessing the alternating hopping strengths will lead to the existence of the topological protected edge modes, also called zero energy modes, when the boundaries leave the weak hopping at two ends. Due to the two edge modes, i.e., symmetric and antisymmetric, with nearly degenerate frequencies, the dynamics of two QDs coupled to the cavities at both ends exhibit complicated behaviors. When the CCAs are composed of a large number of cavities, there are two kinds of phenomena: if the coupling between QDs and cavity is weak, two edge modes will cancel each other out and isolate two QDs deeply; if the coupling between QDs and cavities is large compared with hopping strength, the edge mode disappears and two QDs can be connected through extend modes. Importantly, when the CCAs are formed by a small number of cavities, energy can be transferred to each other between two QDs through the edge modes. Such energy transfer is topologically protected, and the period is long and easily controlled. We also investigate the effects of topologically protected quantum entangled states on such system and find that the quantum entanglement can be well kept or generated for appropriate choices of system parameters and initial states. The investigations enrich the manifestation of topological physics and are helpful to apply the topological protection to quantum computation and quantum communication.

6.
Opt Express ; 29(11): 16182-16196, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34154187

RESUMO

The chiral interaction between light and matter is mainly caused by the spin-momentum locking and makes the chiral quantum optics enter a vigorous development stage. Here, we explore the condition of the perfect chiral interaction between an atom possessing circular dipole and the surface plasmon polariton (SPP) mode. The realization of the perfect chiral interaction must satisfy the following two conditions at the same time. First, the SPP mode should possess the transverse circular polarization; and second, the atom decays mainly into the SPP mode, while the decay through other channel can be ignored. In this paper, we adopt a simple but effective structure to satisfy both of requirements, which is the sandwiched waveguide made of metal. We found that the transverse circular polarization of SPP mode might be achieved within the structure possessing multiple interfaces instead of the interface separating two semi-infinite materials. In our model, the decay rate into SPP mode overwhelms that through traveling wave, which provides higher quantum efficiency. What's more, we found that only the symmetric TM-polarized SPP mode might get the transverse circular polarization. For the sandwiched structure containing metal, the existence of two SPP modes weakens the overall chiral interaction. However, the structure containing left-handed materials (LHMs), which can only support one symmetric TM-polarized SPP mode, can get the nearly perfect chiral interaction. We measure the chiral interaction through the decay rate, radiation field distribution and the unidirectional rate through the energy flux. Our work provides a reference for exploring the perfect chiral interaction in more complex structures and has potential and wide applicability to other optical processes.

7.
Int J Food Microbiol ; 160(3): 245-51, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23290231

RESUMO

AphA is a small PadR-family DNA-binding regulator in vibrios. AphA has been shown to be involved in transcriptional auto-repression, intestinal colonization and lethality in mice, biofilm formation, and quorum sensing in Vibrio cholerae. The AphA protein of Vibrio parahaemolyticus has 85% identity to that of V. cholerae with the same number of amino acids. In this work, the aphA null mutant was constructed from a wild-type pandemic strain of V. parahaemolyticus for characterization of the phenotypic changes. AphA is required for biofilm formation in V. parahaemolyticus, and a decreased production of biofilm exopolysaccharide matrix in the aphA mutant relative to the wild-type parent strain accounts for its reduced biofilm formation. AphA is also necessary for the optimal swimming and swarming motility of V. parahaemolyticus. In addition, AphA is essential for lethality in mice and cytotoxic activity, but the aphA deletion did not have effect on enterotoxicity.


Assuntos
Biofilmes , Transativadores/genética , Transativadores/metabolismo , Vibrioses/microbiologia , Vibrio parahaemolyticus/fisiologia , Virulência/genética , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Hemólise/genética , Camundongos , Dados de Sequência Molecular , Mutação , Coelhos , Alinhamento de Sequência , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/patogenicidade
8.
Fitoterapia ; 78(1): 12-5, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17084991

RESUMO

The effects of Dioscorea opposita (huai shan yao, HSY) on dexamethasone-induced insulin resistance were investigated in vitro and in vivo. D. opposita extract reduced significantly the blood insulin and glucose levels in dexamethasone-induced diabetic rats. In vitro, HSY significantly enhanced insulin-stimulated glucose uptake in 3T3-L1 adipocytes. Moreover, HSY increase the mRNA expression of GLUT4 glucose transporter in 3T3-L1 adipocytes. These data suggest that D. opposita has insulin sensitivity that is associated with the regulation of GLUT4 expression.


Assuntos
Dioscorea , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Fitoterapia , Extratos Vegetais/farmacologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Administração Oral , Animais , Glicemia/metabolismo , Dexametasona , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Feminino , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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