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1.
Nanotechnology ; 35(11)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38081082

RESUMO

Colloidal gold nanorods (GNRs) have demonstrated their potential to absorb light within specific wavelength bands and induce photothermal effects. However, the unpredictability and lack of adjustability in the broadband spectrum formed by the self-assembly of gold nanospheres or the coupling of various sizes of GNRs have posed significant challenges. To address this, we have developed broadband GNRs (BGNRs) with a predictable and adjustable extinction band in the visible and near-infrared regions. The BGNRs were synthesized by simply mixing GNRs with different aspect ratios, allowing for control over the bandwidths and positions of the extinction bands. Subsequently, the BGNRs were coated with silica and underwent surface modification. The resulting BGNRs@SiO2were then mixed with either polydimethylsiloxane (PDMS) or polyvinylidene fluoride (PVDF) to create BGNRs@SiO2/PDMS (or PVDF) films. The BGNRs@SiO2/PDMS and BGNRs@SiO2/PVDF films both exhibit excellent photothermal performance properties. Additionally, the light absorption intensity of the BGNRs@SiO2/PVDF film linearly increases upon folding, leading to significantly enhanced photothermal performance after folding. This work demonstrates that plasmonic colloidal GNRs, without the need for coupling, can yield predictable and adjustable extinction bands. This finding holds great promise for future development and practical applications, particularly in the transfer of these properties to films.

2.
Int J Mol Sci ; 24(6)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36983022

RESUMO

The chronic wound represents a serious disease characterized by a failure to heal damaged skin and surrounding soft tissue. Mesenchymal stem cells (MSCs) derived from adipose tissue (ADSCs) are a promising therapeutic strategy, but their heterogeneity may result in varying or insufficient therapeutic capabilities. In this study, we discovered that all ADSCs populations expressed platelet-derived growth factor receptor ß (PDGFR-ß), while the expression level decreased dynamically with passages. Thus, using a CRISPRa-based system, we endogenously overexpressed PDGFR-ß in ADSCs. Moreover, a series of in vivo and in vitro experiments were conducted to determine the functional changes in PDGFR-ß activation ADSCs (AC-ADSCs) and to investigate the underlying mechanisms. With the activation of PDGFR-ß, AC-ADSCs exhibited enhanced migration, survival, and paracrine capacity relative to control ADSCs (CON-ADSCs). In addition, the secretion components of AC-ADSCs contained more pro-angiogenic factors and extracellular matrix-associated molecules, which promoted the function of endothelial cells (ECs) in vitro. Additionally, in in vivo transplantation experiments, the AC-ADSCs transplantation group demonstrated improved wound healing rates, stronger collagen deposition, and angiogenesis. Consequently, our findings revealed that PDGFR-ß overexpression enhanced the migration, survival, and paracrine capacity of ADSCs and improved therapeutic effects after transplantation to diabetic mice.


Assuntos
Diabetes Mellitus Experimental , Células-Tronco Mesenquimais , Camundongos , Animais , Células Endoteliais , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Experimental/metabolismo , Cicatrização , Células-Tronco Mesenquimais/metabolismo , Matriz Extracelular , Tecido Adiposo
3.
Sheng Li Xue Bao ; 74(3): 461-468, 2022 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-35770643

RESUMO

Histone methylation is one of the key post-translational modifications that plays a critical role in various heart diseases, including diabetic cardiomyopathy. A great deal of evidence has shown that histone methylation is closely related to hyperglycemia, insulin resistance, lipid and advanced glycation end products deposition, inflammatory and oxidative stress, endoplasmic reticulum stress and cell apoptosis, and these pathological factors play an important role in the pathogenesis of diabetic cardiomyopathy. In order to provide a novel theoretical basis and potential targets for the treatment of diabetic cardiomyopathy from the perspective of epigenetics, this review discussed and elucidated the association between histone methylation and the pathogenesis of diabetic cardiomyopathy in details.


Assuntos
Diabetes Mellitus , Cardiomiopatias Diabéticas , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/patologia , Histonas , Humanos , Metilação , Estresse Oxidativo , Processamento de Proteína Pós-Traducional
4.
Zhonghua Nan Ke Xue ; 28(5): 408-414, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-37477479

RESUMO

OBJECTIVE: To investigate the value of single-sperm sequencing technology in preimplantation genetic testing. METHODS: Haplotypes were constructed by single-sperm isolation combined with single-sperm sequencing for a patient with autosomal dominant polycystic kidney disease (ADPKD) caused by de novo mutation of the PKD1 gene c.3815T>G. 50. Single-sperm samples were isolated by mechanical braking, whole-genome amplification was performed, and mutation loci and their 187 upstream and downstream single nucleotide polymorphisms (SNP) were designed. The amplified products were verified for determination of the chromosome haplotypes carrying or not carrying pathogenic mutations. The embryos carrying pathogenic mutations were identified in 7 embryonic trophectoderm cell biopsy samples by high-throughput sequencing after whole-genome amplification. Available blastocysts were selected for embryo transfer, and amniotic fluid samples were collected at 18 weeks of gestation to determine whether the fetuses carried pathogenic mutations. RESULTS: A total of 30 SNPs were identified by single-sperm sequencing, and haplotypes were successfully constructed. Preimplantation haplotype analysis indicated that 5 embryos carried pathogenic mutations and 2 did not. mid-gestation amniotic fluid genetic testing revealed no PKD1 gene c.3815T>G mutation in the fetuses. CONCLUSION: SNPs can be identified by single-sperm sequencing in males carrying de novo pathogenic mutation, and haplotypes can be constructed by linkage analysis for preimplantation genetic testing of embryos.


Assuntos
Rim Policístico Autossômico Dominante , Diagnóstico Pré-Implantação , Gravidez , Feminino , Humanos , Masculino , Rim Policístico Autossômico Dominante/genética , Sêmen , Testes Genéticos , Mutação , Sequenciamento de Nucleotídeos em Larga Escala , Espermatozoides , Tecnologia
5.
J Am Chem Soc ; 143(16): 6025-6036, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33857372

RESUMO

Stimuli-responsive multifunctional mesoporous silica nanoparticles (MSNs) have been studied intensively during the past decade. A large variety of mesopore capping systems have been designed, initially to show that it could be done and later for biomedical applications such as drug delivery and imaging. On-command release of cargo molecules such as drugs from the pores can be activated by a variety of stimuli. This paper focuses on three noninvasive, biologically usable external stimuli: magnetism, ultrasound, and light. We survey the variety of MSNs that have been and are being used and assess capping designs and the advantages and drawbacks of the nanoplatforms' responses to the various stimuli. We discuss important recent advances, their basic mechanisms, and their requirements for stimulation. On the basis of our survey, we identify fundamental challenges and suggest future directions for research that will unleash the full potential of these fascinating nanosystems for clinical applications.


Assuntos
Luz , Campos Magnéticos , Nanoestruturas/química , Dióxido de Silício/química , Nanomedicina Teranóstica , Ondas Ultrassônicas , Portadores de Fármacos/química , Humanos , Nanopartículas Magnéticas de Óxido de Ferro/química , Porosidade
6.
Opt Express ; 29(5): 6407-6423, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33726162

RESUMO

Stationary source emissions of key industries, such as thermal power plants, have become the central consideration in environmental protection programs. Existing photoelectric sensors at stationary sources usually use a single wavelength laser to measure the total mass concentration of the particulate matter, bearing inherent errors due to the changing particle size distribution (PSD). However, the total mass concentration cannot comprehensively estimate the air pollution caused by the stationary sources. Therefore, it is required to measure both the mass concentration and PSD of the aerosols emitted by the stationary sources, based on which we can get a distributed mass concentration. To implement this, in this study, we designed a novel three-wavelength photoelectric sensor and tested its performance. Results showed that the prototype correctly determines the mean particle size and standard deviation of the PSDs and consequently adjusts the coefficient for measuring the mass concentration from light intensity, providing a comprehensive assessment of the pollutants.

7.
Phys Rev Lett ; 127(8): 086801, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34477399

RESUMO

In a closed system, it is well known that the time-reversal symmetry can lead to Kramers degeneracy and protect nontrivial topological states such as the quantum spin Hall insulator. In this Letter, we address the issue of whether these effects are stable against coupling to the environment, provided that both the environment and the coupling to the environment also respect time-reversal symmetry. By employing a non-Hermitian Hamiltonian with the Langevin noise term and utilizing the non-Hermitian linear response theory, we show that the spectral functions for Kramers degenerate states can be split by dissipation, and the backscattering between counterpropagating edge states can be induced by dissipation. The latter leads to the absence of accurate quantization of conductance in the case of the quantum spin Hall effect. As an example, we demonstrate this concretely with the Kane-Mele model. Our study can also include interacting topological phases protected by time-reversal symmetry.

8.
Pharmazie ; 76(2): 84-91, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33714284

RESUMO

Context: Daidzein is a secondary metabolite derived from plants, has a flavonoid structure and is known for its protective activity in gastrointestinal disorders. Objective: The current work determines the preventive effect of daidzein against injury in the esophagus mucosa induced by esophageal reflux (RE) in an animal model. Methods: Adult male Wistar rats were classified into six groups: normal control, ER + different doses of daidzein and ER + omeprazole. RE was induced in all animals except controls and supplemented with daidzein and standard drugs orally for 6 hours. Serum and tissue were used for further biochemical parameters. Results: Daidzein as a flavonoid has antioxidant properties and shows in vitro antioxidant activity. The outcomes also reveal an elevation in lipid peroxidation and a decline in the levels of sulphhydryl groups and glutathione, along with the depletion in the activities of enzymatic antioxidants in the oxidative stress state. In a dose-dependent manner daidzein and omeprazole amended all macroscopic and biochemical variations and protected against the raised level of hydrogen peroxide (H2O2), calcium and free iron levels in esophageal tissue induced during RE. It also improved the expression and level of proinflammatory cytokines. Conclusion: The finding reports that daidzein has a potential to show a shielding effect against esophagus damage induced by RE in rats, at least in part via alteration of inflammatory cytokines.


Assuntos
Anti-Inflamatórios/farmacologia , Citocinas/efeitos dos fármacos , Mucosa Esofágica/efeitos dos fármacos , Refluxo Gastroesofágico/tratamento farmacológico , Isoflavonas/farmacologia , Animais , Antioxidantes/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Claudina-4/metabolismo , Claudina-5/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Mucosa Esofágica/lesões , Esôfago/efeitos dos fármacos , Esôfago/metabolismo , Refluxo Gastroesofágico/induzido quimicamente , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Células RAW 264.7 , Ratos , Ratos Wistar
9.
Biochem Biophys Res Commun ; 522(3): 704-708, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-31787232

RESUMO

AMPK is generally a tumor suppressor. However, once cancer arises, AMPK becomes a tumor promoter instead, driving cancer development. For such AMPK-driven cancers, AMPK blockade may be a valuable therapeutic strategy. Here we show that AMPK is upregulated in a variety of hematological cancers and plays key roles in maintaining viability of tumor cells. Blockade of AMPK signaling by dorsomorphin markedly induces apoptosis in Jurkat, K562 cell lines as well as primary cancerous B cells. Mechanistically, dorsomorphin significantly upregulates the expression of BAD, a pro-apoptotic member of the Bcl-2 gene family involved in initiating apoptosis. Reduction of BAD expression by RNA interference prevents apoptosis in response to AMPK inhibition. Thus, our data found BAD integrates the pro-apoptotic effects of dorsomorphin and provided novel insights into the mechanisms by which AMPK facilitates survival signaling in hematologic tumor cells.


Assuntos
Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Leucemia/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Proteína de Morte Celular Associada a bcl/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Humanos , Células Jurkat , Células K562 , Leucemia/genética , Leucemia/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
10.
Phys Rev Lett ; 124(5): 050502, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32083915

RESUMO

We report the experimental implementation of discrete-time topological quantum walks of a Bose-Einstein condensate in momentum space. Introducing stroboscopic driving sequences to the generation of a momentum lattice, we show that the dynamics of atoms along the lattice is effectively governed by a periodically driven Su-Schrieffer-Heeger model, which is equivalent to a discrete-time topological quantum walk. We directly measure the underlying topological invariants through time-averaged mean chiral displacements, which are consistent with our experimental observation of topological phase transitions. We then observe interaction-induced localization in the quantum-walk dynamics, where atoms tend to populate a single momentum-lattice site under interactions that are nonlocal in momentum space. Our experiment opens up the avenue of investigating discrete-time topological quantum walks using cold atoms, where the many-body environment and tunable interactions offer exciting new possibilities.

11.
Phys Rev Lett ; 124(7): 070402, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32142332

RESUMO

We report the experimental observation of tunable, nonreciprocal quantum transport of a Bose-Einstein condensate in a momentum lattice. By implementing a dissipative Aharonov-Bohm (AB) ring in momentum space and sending atoms through it, we demonstrate a directional atom flow by measuring the momentum distribution of the condensate at different times. While the dissipative AB ring is characterized by the synthetic magnetic flux through the ring and the laser-induced loss on it, both the propagation direction and transport rate of the atom flow sensitively depend on these highly tunable parameters. We demonstrate that the nonreciprocity originates from the interplay of the synthetic magnetic flux and the laser-induced loss, which simultaneously breaks the inversion and the time-reversal symmetries. Our results open up the avenue for investigating nonreciprocal dynamics in cold atoms, and highlight the dissipative AB ring as a flexible building element for applications in quantum simulation and quantum information.

12.
Protein Expr Purif ; 174: 105678, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32446879

RESUMO

Dental plaque is a high-incidence health concern, and it is caused by Streptococcus mutans. Dextranase can specifically hydrolyze ɑ-1,6-glycosidic linkages in dextran. It is commonly used in the sugar industry, in the production of plasma substitutes, and the treatment and prevention of dental plaque. In this research work, we successfully cloned and expressed a cold-adapted dextranase from marine bacteria Catenovulum sp. DP03 in Escherichia coli. The recombinant dextranase named Cadex2870 contained a 2511 bp intact open reading frame and encoded 836 amino acids. The expression condition of recombinant strain was 0.1 mM isopropylthio-galactoside (IPTG), and the reduced temperature was 16 °C. The purified enzyme activity was 16.2 U/mg. The optimal temperature and pH of Cadex2870 were 45 °C and pH 8, and it also had catalytic activity at 0 °C. The hydrolysates of Cadex2870 hydrolysis Dextran T70 are maltose, maltotetraose, maltopentose, maltoheptaose and higher molecular weight maltooligosaccharides. Interestingly, 0.5% sodium benzoate, 2% xylitol, 0.5% sodium fluoride, 5% propanediol, 5% glycerin and 2% sorbitol can enhance stability Cadex2870, which are additives in mouthwashes. Additionally, Cadex2870 reduced the formation of dental plaque and effectively degraded formed plaque. Therefore, Cadex2870 shows great promise in commercial applications.


Assuntos
Alteromonadaceae , Organismos Aquáticos , Proteínas de Bactérias , Placa Dentária/tratamento farmacológico , Dextranase , Expressão Gênica , Streptococcus mutans/crescimento & desenvolvimento , Aclimatação , Alteromonadaceae/enzimologia , Alteromonadaceae/genética , Organismos Aquáticos/enzimologia , Organismos Aquáticos/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/farmacologia , Temperatura Baixa , Placa Dentária/microbiologia , Dextranase/biossíntese , Dextranase/genética , Dextranase/isolamento & purificação , Dextranase/farmacologia , Humanos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia
13.
Acta Biochim Biophys Sin (Shanghai) ; 52(5): 485-494, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32318691

RESUMO

Feedback regulation plays a pivotal role in determining the intensity and duration of TGF-ß signaling and subsequently affecting the pathophysiological roles of TGF-ß, including those in liver malignancy. KLF2, a member of the Krüppel-like factor (KLF) family transcription factors, has been implicated in impeding hepatocellular carcinoma (HCC) development. However, the underlying molecular mechanisms are not fully understood. In the present study, we found that TGF-ß stimulates the expression of KLF2 gene in several HCC cell lines. KLF2 protein is able to inhibit TGF-ß/Smad signaling in HCC cells as assessed by luciferase reporter assay. Further studies indicated that KLF2 inhibits the transcriptional activity of Smad2/3 and Smad4 and ameliorates TGF-ß-induced target gene expression, therefore creating a novel negative feedback loop in TGF-ß signaling. Functionally, stably expression of KLF2 in HCCLM3 cells attenuated TGF-ß-induced cancer cell motility in wound-healing and transwell assays by interfering with TGF-ß-mediated upregulation of MMP2. Together, our results revealed that KLF2 protein has a tumor-suppressive function in HCC through a negative feedback loop over TGF-ß signaling.


Assuntos
Carcinoma Hepatocelular/metabolismo , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição Kruppel-Like/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Humanos , Fatores de Transcrição Kruppel-Like/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas de Neoplasias/genética , Fator de Crescimento Transformador beta/genética
14.
Nano Lett ; 19(7): 4314-4320, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31184897

RESUMO

Nanoparticle assemblies have generated intense interest because of their novel optical, electronic, and magnetic properties that open up numerous opportunities in fundamental and applied nanophotonics, -electronics, and -magnetics. However, despite the great scientific and technological potential of these structures, it remains an outstanding challenge to reliably fabricate such assemblies with both nanometer-level structural control and precise spatial arrangements on a macroscopic scale. It is the combination of these two features that is key to realizing nanoparticle assemblies' potential, particular for device applications. To address this challenge, we propose a hierarchical assembly approach consisting of both template-particle and particle-particle interactions, whereby the former ensures precise addressability of assemblies on a surface and the latter provides nanometer-level structural control. Template-particle interactions are harnessed via chemical-pattern-directed assembly, and the particle-particle interactions are controlled using DNA-directed self-assembly. To demonstrate the potential of this hierarchical assembly approach, we demonstrate the fabrication of a particularly fascinating assembly: the nanoparticle heterodimer, which possesses a surprisingly rich set of plasmonic properties and is a promising candidate to enable a variety of imaging and sensing applications. Each heterodimer is placed on the surface at predetermined locations, and the precise control of the nanogaps is confirmed by far-field scattering measurements of individual dimers. We further demonstrate that the gap size can be effectively tuned by varying the DNA length. By correlating measured spectra with finite-difference time-domain (FDTD) simulations, we determine the gap sizes to be 4.2 and 5.0 nm-with subnm deviation-for the two DNA lengths investigated. This is one of the best gap uniformities ever demonstrated for surface-bound nanoparticle assemblies. The estimated surface-enhanced Raman scattering (SERS) enhancement factor of these heterodimers is on the order of 105-106 with high reproducibility and predictable polarization-dependence. This hierarchical fabrication technique-employing both template-particle and particle-particle interactions-constitutes a novel platform for the realization of functional nanoparticle assemblies on surfaces and thereby creates new opportunities to implement these structures in a variety of applications.

15.
Small ; 15(46): e1902647, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614073

RESUMO

Integrating multiple strategies of antibacterial mechanisms into one has been proven to have tremendous promise for improving antimicrobial efficiency. Hence, dual-valent platinum nanoparticles (dvPtNPs) with a zero-valent platinum core (Pt0 ) and bi-valent platinum shell (Pt2+ ions), combining photothermal and photodynamic therapy, together with "chemotherapy," emerge as spatiotemporally light-activatable platinum nano-antibiotics. Under near-infrared (NIR) exposure, the multiple antibacterial modes of dvPtNPs are triggered. The Pt0 core reveals significant hyperthermia via effective photothermal conversion while an immediate release of chemotherapeutic Pt2+ ions occurs through hyperthermia-initiated destabilization of metallic interactions, together with reactive oxygen species (ROS) level increase, thereby resulting in synergistic antibacterial effects. The precise cooperative effects between photothermal, photodynamic, and Pt2+ antibacterial effects are achieved on both Gram-negative Escherichia coli and Gram-positive methicillin-resistant Staphylococcus aureus, where bacterial viability and colony-forming units are significantly reduced. Moreover, similar results are observed in mice subcutaneous abscess models. Significantly, after NIR treatment, dvPtNP exhibits a more robust bacteria-killing efficiency than other PtNP groups, owing to its integration of dramatic damage to the bacterial membrane and DNA, and alteration to ATP and ROS metabolism. This study broadens the avenues for designing and synthesizing antibacterial materials with higher efficiency.


Assuntos
Antibacterianos/farmacologia , Luz , Nanopartículas/química , Platina/farmacologia , Animais , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Feminino , Nanopartículas Metálicas/ultraestrutura , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Células NIH 3T3
16.
Mar Drugs ; 17(10)2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31635432

RESUMO

Dextranase, a hydrolase that specifically hydrolyzes α-1,6-glucosidic bonds, has been used in the pharmaceutical, food, and biotechnology industries. In this study, the strain of Catenovulum agarivorans MNH15 was screened from marine samples. When the temperature, initial pH, NaCl concentration, and inducer concentration were 30 °C, 8.0, 5 g/L, and 8 g/L, respectively, it yielded more dextranase. The molecular weight of the dextranase was approximately 110 kDa. The maximum enzyme activity was achieved at 40 °C and a pH of 8.0. The enzyme was stable at 30 °C and a pH of 5-9. The metal ion Sr2+ enhanced its activity, whereas NH4+, Co2+, Cu2+, and Li+ had the opposite effect. The dextranase effectively inhibited the formation of biofilm by Streptococcus mutans. Moreover, sodium fluoride, xylitol, and sodium benzoate, all used in dental care products, had no significant effect on dextranase activity. In addition, high-performance liquid chromatography (HPLC) showed that dextran was mainly hydrolyzed to glucose, maltose, and maltoheptaose. The results indicated that dextranase has high application potential in dental products such as toothpaste and mouthwash.


Assuntos
Alteromonadaceae/metabolismo , Organismos Aquáticos/metabolismo , Placa Dentária/tratamento farmacológico , Dextranase/farmacologia , Biofilmes/efeitos dos fármacos , Dextranase/química , Dextranos/química , Glucanos/química , Glucanos/farmacologia , Glucose/química , Concentração de Íons de Hidrogênio , Hidrólise , Maltose/química , Peso Molecular , Antissépticos Bucais/química , Streptococcus mutans/efeitos dos fármacos , Dente/efeitos dos fármacos , Cremes Dentais/química
17.
Biochem Biophys Res Commun ; 501(1): 199-205, 2018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29709471

RESUMO

Circular RNAs (circRNAs) are noncoding RNAs that can function as miRNA sponges, post-transcriptionally regulating the expression of genes. Here, we report a novel positive function of mm9_circ_009056 during osteogenesis in regulating bone morphogenetic protein 7 (BMP7) through miR-22-3p. First, we found that calcitonin gene-related peptide (CGRP) had great osteogenesis function on MC3T3 cells. Then aberrant expression of mm9_circ_009056 were confirmed in CGRP-induced cells. Furthermore, the expression of mm9_circ_009056 was up-regulated in the CGRP-induced cells, whereas miR-22-3p was obviously decreased. Silencing of mm9_circ_009056 increased the expression of miR-22-3p and decreased the gene and protein levels of BMP7, RUNX2. Cells proliferation and growth were also inhibited following silengcing. The protein levels of BMP7 and RUNX2 decreased after mimics transfection and increased after inhibitors transfection. In summary, mm9_circ_009056 may function as a sponge for miR-22-3p to regulate osteogenesis in CGRP-induced cells.


Assuntos
Proteína Morfogenética Óssea 7/genética , Proteína Morfogenética Óssea 7/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/genética , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Osteogênese/genética , Osteogênese/fisiologia , RNA/genética , RNA/metabolismo , Células 3T3 , Animais , Proliferação de Células , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Expressão Gênica , Camundongos , Interferência de RNA , RNA Circular , RNA Interferente Pequeno/genética
18.
Nano Lett ; 17(12): 7196-7206, 2017 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-29111760

RESUMO

An extension of the Maxwell-Faraday law of electromagnetic induction to optical frequencies requires spatially appropriate materials and optical beams to create resonances and excitations with curl. Here we employ cylindrical vector beams with azimuthal polarization to create electric fields that selectively drive magnetic responses in dielectric core-metal nanoparticle "satellite" nanostructures. These optical frequency magnetic resonances are induced in materials that do not possess spin or orbital angular momentum. Multipole expansion analysis of the scattered fields obtained from electrodynamics simulations show that the excitation with azimuthally polarized beams selectively enhances magnetic vs electric dipole resonances by nearly 100-fold in experiments. Multipolar resonances (e.g., quadrupole and octupole) are enhanced 5-fold by focused azimuthally versus linearly polarized beams. We also selectively excite electric multipolar resonances in the same identical nanostructures with radially polarized light. This work opens new opportunities for spectroscopic investigation and control of "dark modes", Fano resonances, and magnetic modes in nanomaterials and engineered metamaterials.

19.
Biochem Biophys Res Commun ; 490(3): 827-833, 2017 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-28647364

RESUMO

Antibiotic resistance is becoming a global threat and overuse of antibiotics in aquaculture disease control worsens the situation. To reduce the risk of drug resistance developed in aquaculture, safer biocontrol programs are needed. Antivirulence therapy, with less chance for developing drug resistance, is a promising approach. To facilitate antivirulence inhibitor design against Vibrio anguillarum, a serious aquaculture pathogen, we present crystal structures for isochorismatase domains of AngB and VabB, which are required to synthesize siderophore, a critical virulence factor. Both structures are highly similar to known isochorismatases in fold and active site, therefore we conclude inhibitors for isochorismatases can be developed in a common framework. The structural information will improve design of virulence inhibitors against Vibrio anguillarum. We also firstly report that isochorismatase family could bind endogenous metabolite during the hetero-expression process, which is likely nicotinic acid, nicotinamide or pyrazinic acid, based on structural analysis and affinity prediction. Taken together, our results provide precise structural information of isochorismatase domains for antivirulence inhibitor design against Vibrio anguillarum.


Assuntos
Hidrolases/química , Vibrio/enzimologia , Sequência de Aminoácidos , Domínio Catalítico , Cristalografia por Raios X , Desenho de Fármacos , Humanos , Hidrolases/antagonistas & inibidores , Hidrolases/metabolismo , Modelos Moleculares , Conformação Proteica , Domínios Proteicos , Alinhamento de Sequência , Vibrio/química , Vibrio/metabolismo , Vibrioses/microbiologia
20.
Nano Lett ; 16(3): 1818-25, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26871607

RESUMO

We performed single particle deformation experiments on silica-coated gold nanorods under femtosecond (fs) illumination. Changes in the particle shape were analyzed by electron microscopy and associated changes in the plasmon resonance by electron energy loss spectroscopy. Silica-coated rods were found to be more stable compared to uncoated rods but could still be deformed via an intermediate bullet-like shape for silica shell thicknesses of 14 nm. Changes in the size ratio of the rods after fs-illumination resulted in blue-shifting of the longitudinal plasmon resonances. Two-dimensional spatial mapping of the plasmon resonances revealed that the flat side of the bullet-like particles showed a less pronounced longitudinal plasmonic electric field enhancement. These findings were confirmed by finite-difference time-domain (FDTD) simulations. Furthermore, at higher laser fluences size reduction of the particles was found as well as for particles that were not completely deformed yet.

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