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1.
Phys Rev Lett ; 128(22): 220503, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35714245

RESUMO

We describe and analyze algorithms for classically simulating measurement of an n-qubit quantum state in the standard basis, that is, sampling a bit string from the probability distribution determined by the Born rule. Our algorithms reduce the sampling task to computing poly(n) amplitudes of n-qubit states; unlike previously known techniques they do not require computation of marginal probabilities. Two classes of quantum states are considered: output states of polynomial-size quantum circuits, and ground states of local Hamiltonians with an inverse polynomial spectral gap. We show that our algorithms can significantly accelerate quantum circuit simulations based on tensor network contraction or low-rank stabilizer decompositions. As another striking consequence we obtain the first efficient classical simulation algorithm for measurement-based quantum computation with the surface code resource state on any planar graph and any schedule of measurements.

2.
Regen Ther ; 19: 122-130, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35229010

RESUMO

BACKGROUND: Periodontitis is a common chronic oral disease among the world. Periodontal ligament stem cells (PDLSCs) has been proved to be a promising tool for the treatment of periodontitis due to their capability of generating periodontal tissues. Circ_0087960 and KDM5B have been shown to participate in the process of osteogenic differentiation with unclear function and mechanism. METHODS: Circ_0087960 and KDM5B expressions were detected during the osteogenic induction of PDLSCs. The functions of circ_0087960 and KDM5B were validated by manipulating their expression with shRNA. ChIP and luciferase reporter assays were used to prove the KDM5B-based osteogenic gene regulation. Co-IP assay was used to determine the interaction between SKP2 and KDM5B. In vivo ubiquitination assay was used to test the modification of KDM5B by SKP2. RNA pull-down was used to demonstrate the interaction between circ_0087960 and KDM5B. RESULTS: Circ_0087960 and KDM5B were found to be upregulated in the osteogenic differentiation of PDLSCs and promote the expression of related genes. KDM5B could directly bind and promote the expression of Runx2, ALP and OCN. KDM5B protein level in PDLSCs was controlled by SKP2-mediated protein ubiquitination and degradation. Circ_0087960 was identified to bind to KDM5B protein and protect it against SKP2-induced protein degradation, leading to the upregulation of osteogenic genes. CONCLUSION: Circ_0087960 and KDM5B could be applied as promising therapeutic methods to stimulate the osteogenic differentiation of PDLSCs, expanding their capability in the treatment of periodontitis.

3.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 39(1): 94-98, 2021 Feb 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33723943

RESUMO

Resolution of inflammation plays an important part in maintaining homeostasis. It is an actively programmed progress involving multiple immune cells and mediators. Specialized pro-resolving mediators (SPMs) derived from Ω-3 polyunsaturated fatty acids include resolvins, protectins and maresins, and they exert abilities in the resolution of inflammation, host defense, organ protection, and tissue generation. Periodontitis is an inflammatory and destructive disease in the periodontal tissue initiated by dental plaque. Inadequate proinflammatory or proresolving responses, or the imbalance between the two, may contribute to the pathogenesis of the disease. Studies have shown that activating specialized receptors SPMs displayed multiple biological effects towards periodontitis, including resolution of inflammation, alveolar bone protection, periodontal tissue regeneration, and pathogen resistance. Thus, the relationship between SPM and periodontitis and the potentials and challenges in SPM application were reviewed.


Assuntos
Ácidos Graxos Ômega-3 , Periodontite , Homeostase , Humanos , Inflamação , Mediadores da Inflamação
4.
Dent Mater J ; 39(6): 933-940, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33028784

RESUMO

Apigenin is a type of flavonols that exhibits anti-caries properties. Bacterial adherence is the initial step in the forming of a stable biofilm that leads to caries. Bacterial adherence is affected by surface characteristics, including hydrophobicity and bacterial aggregation. However, the effect of apigenin on surface characteristics of cariogenic bacteria has not been reported. We aimed to examine the effects of apigenin on adherence and biofilm formation of Streptococcus mutans UA159. Hydrophobicity and bacterial aggregation, pac and gbpC gene expressions, and cytotoxicity on human dental pulp cells were also determined. Apigenin significantly inhibited the adherence and biofilm formation of S. mutans. Hydrophobicity decreased, whereas the aggregation rate was significantly increased compared with the control. Apigenin significantly suppressed pac and gbpC gene expressions. Apigenin exhibited acceptable biocompatibility on hDPCs. Thus, apigeinin may affect adherence and biofilm formation by altering the surface properties of S. mutans without obvious adverse effect on hDPCs.


Assuntos
Cárie Dentária , Streptococcus mutans , Apigenina/farmacologia , Biofilmes , Cariostáticos , Cárie Dentária/prevenção & controle , Humanos
5.
J Diabetes Investig ; 9(5): 1041-1051, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29427460

RESUMO

AIMS/OBJECTIVE: The present study aimed to explore the effects of micro-ribonucleic acid-365 (miR-365) on apoptosis of retinal neurons by targeting insulin-like growth factor-1 (IGF-1) in diabetes mellitus rats. MATERIALS AND METHODS: High glucose-induced retinal neurons were assigned into the blank (with no plasmid transfection), negative control (with plasmid transfection), anti-miR-365 (transfected miR-365 antagomir), transfected IGF-1 short hairpin RNA plasmid (sh-IGF-1) and transfected miR-365 antagomir and IGF-1 shRNA plasmid (anti-miR-365 + sh-IGF-1) groups. Proliferation and apoptosis of retinal neurons were detected by 5-ethynyl-2'-deoxyuridine assay and Hoechst 33342 staining, respectively. Expressions of miR-365, IGF-1, Bcl-2-associated X protein (Bax) and Bcl-2 were determined by reverse transcription quantitative polymerase chain reaction and western blotting. A control group contained 10 healthy rats. Terminal deoxynucleotidyl transferase dUTP nick-end labeling staining was used to evaluate apoptosis of retinal neurons in rats. RESULTS: In the anti-miR-365 group, the apoptosis rate and Bax expression were reduced in comparison with the negative control and blank groups, whereas the sh-IGF-1 and anti-miR-365 + sh-IGF-1 groups presented an opposite trend. Compared with the normal group, expressions of miR-365 and Bax were increased, and expressions of IGF-1 and Bcl-2 were decreased, with more apoptotic cells in diabetes mellitus rat models. The sh-IGF-1 group had lower Bax expression, and higher expressions of IGF-1 and Bcl-2 with fewer apoptotic cells. Additionally, Bax expression was upregulated, expressions of IGF-1 and Bcl-2 were downregulated, and apoptotic cells were higher in the anti-miR-365 + sh-IGF-1 groups than the anti-miR-365 group. CONCLUSION: The results of the present study suggest that suppressed miR-365 increases the IGF-1 expression, leading to anti-apoptotic effects on retinal neurons in diabetic rats.


Assuntos
Apoptose/fisiologia , Diabetes Mellitus Experimental/terapia , Marcação de Genes/métodos , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , MicroRNAs/antagonistas & inibidores , Neurônios Retinianos/fisiologia , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Relação Dose-Resposta a Droga , Fator de Crescimento Insulin-Like I/biossíntese , Fator de Crescimento Insulin-Like I/genética , Masculino , MicroRNAs/biossíntese , MicroRNAs/genética , RNA Interferente Pequeno/administração & dosagem , Ratos , Ratos Sprague-Dawley , Neurônios Retinianos/efeitos dos fármacos
6.
Eur J Oral Sci ; 122(4): 286-92, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24965668

RESUMO

The aim of this study was to investigate the effects of different direct current intensities on dentine bonding effectiveness of Clearfil S(3) Bond and on cell viability of human dental pulp cells (HDPCs). Thirty-five-third molars were sectioned and ground to provide flat surfaces. Clearfil S(3) Bond was applied under different current conditions for 30 s and then resin composite was built up. Specimens were processed for microtensile bond strength (µTBS) testing and for nanoleakage investigation using scanning electron microscopy. Primary HDPCs isolated from premolars were stimulated with different intensities of electric current for 30 s. Then, cell viability was tested using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Specimens bonded with application of electrical current intensities of 50, 60, 70, and 90 µA exhibited a significant increase in immediate µTBS compared with all other groups. Bonded interfaces prepared using electrically assisted current application showed reduced interfacial nanoleakage upon scanning electron microscopy. Electric current application, from 20 to 70 µA, had no effect on the viability of HDPCs. This study provides further evidence for its future clinical use.


Assuntos
Colagem Dentária/métodos , Adesivos Dentinários/química , Dentina/ultraestrutura , Eletricidade , Cimentos de Resina/química , Adolescente , Técnicas de Cultura de Células , Proliferação de Células , Sobrevivência Celular/fisiologia , Células Cultivadas , Corantes , Resinas Compostas/química , Infiltração Dentária/classificação , Materiais Dentários/química , Polpa Dentária/citologia , Estimulação Elétrica , Técnicas Eletroquímicas , Humanos , Microscopia Eletrônica de Varredura , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração , Sais de Tetrazólio , Tiazóis , Fatores de Tempo
7.
Stem Cells ; 32(7): 1943-55, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24510807

RESUMO

Sirtuin 6 (SIRT6) is a NAD-dependent deacetylase involved in lifespan regulation. To evaluate the effect of SIRT6 on osteogenesis, rat bone marrow mesenchymal stem cells (rBMSCs) with enhanced or reduced SIRT6 function were developed. We observed that SIRT6 knockdown significantly reduced the mRNA levels of several key osteogenic markers in vitro, including alkaline phosphatase (ALP), Runt-related transcription factor 2 (RUNX2), and osteocalcin, while overexpression of SIRT6 enhanced their expression. Additionally, SIRT6 knockdown activated nuclear factor-κB (NF-κB) transcriptional activity and upregulated the expression of acetyl-NF-κB p65 (Lys310). The decreased osteogenic differentiation ability of rBMSCs could be partially rescued by the addition of NF-κB inhibitor BAY 11-7082. Furthermore, SIRT6 overexpression in rBMSCs combined with the use of collagen/chitosan/hydroxyapatite scaffold could significantly boost new bone formation in rat cranial critical-sized defects, as determined by microcomputed tomography and histological examination. These data confirm that SIRT6 is mainly located in the nuclei of rBMSCs and plays an essential role in their normal osteogenic differentiation, partly by suppressing NF-κB signaling.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/fisiologia , NF-kappa B/metabolismo , Sirtuínas/fisiologia , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Regeneração Óssea , Adesão Celular , Núcleo Celular/enzimologia , Proliferação de Células , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Expressão Gênica , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais , Osteocalcina/genética , Osteocalcina/metabolismo , Osteogênese , Ratos Sprague-Dawley , Transdução de Sinais
8.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 31(5): 453-6, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24298792

RESUMO

OBJECTIVE: To evaluate the effect of an arginine-containing antihypersensitivity polishing paste on Streptococcus mutans (S. mutans) adhesion to treated dentin. METHODS: Dentin discs were treated with acid to expose dentin tubules, and then polished with either pumice or a polishing paste containing arginine. The surface roughness of the treated dentin was measured. The effects of dentin treatment on S. mutans adhesion and glucosyltransferase (GTFs) gene expression were also evaluated. RESULTS: The surface roughness decreased after polishing with both pumice and arginine-containing polishing paste. Moreover, the polishing paste affected gtfB and gtfC expressions. CONCLUSION: The arginine-containing polishing paste affects S. mutans adhesion, as well as gtfB and gtfC expressions. The polishing paste may be used to prevent caries in exposed dentin areas.


Assuntos
Arginina , Aderência Bacteriana , Streptococcus mutans , Dentina , Humanos , Pomadas , Silicatos , Cremes Dentais
9.
J Dent ; 41(7): 619-27, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23643848

RESUMO

OBJECTIVES: To evaluate the influence of desensitising paste containing 8% arginine and calcium carbonate (Ar-Ca) on biofilm formation on dentine. METHODS: Dentine discs were cut from extracted third molars and divided into the following three groups: no treatment, pumice treatment and Ar-Ca treatment. Surface topography and roughness were examined using scanning electron microscopy (SEM) and non-contact 3D surface profiler. After sterilisation, samples were incubated with Streptococcus mutans (S. mutans) for 4 h, 24 h and 72 h. Bacterial adhesion and biofilm formation were analysed using SEM, whereas MTT and lactic acid production assays were used to analyse the metabolic activity of S. mutans. RESULTS: After polishing with either pumice or Ar-Ca, the surfaces of the samples became smoother than in the control group. The Ra values of the three experimental groups decreased significantly to 0.43 µm, 0.3 µm and 0.26 µm, respectively. Compared to the control group, fewer bacteria adhered to the dentine surface in the Ar-Ca group, while biofilm thickness decreased significantly for both groups after incubating for 24 h and 72 h. MTT and lactic acid production levers also showed a significant reduction in the Ar-Ca group. CONCLUSIONS: Ar-Ca appears to present antibiofilm efficacy and may provide a promising approach to combat bacterial infection in hypersensitive dentinal lesions. CLINICAL SIGNIFICANCE: As a clinical application of desensitising polishing paste, the paste containing 8% arginine and calcium carbonate could also inhibit the biofilm formation effectively.


Assuntos
Arginina/farmacologia , Biofilmes/efeitos dos fármacos , Carbonato de Cálcio/farmacologia , Dentifrícios/farmacologia , Dessensibilizantes Dentinários/farmacologia , Fluoretos/farmacologia , Fosfatos/farmacologia , Streptococcus mutans/efeitos dos fármacos , Adolescente , Adulto , Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Corantes , Profilaxia Dentária/métodos , Dentina/microbiologia , Dentina/ultraestrutura , Humanos , Imageamento Tridimensional/métodos , Ácido Láctico/metabolismo , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Silicatos/farmacologia , Streptococcus mutans/fisiologia , Sais de Tetrazólio , Tiazóis , Fatores de Tempo , Adulto Jovem
10.
Molecules ; 16(2): 1682-94, 2011 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21330957

RESUMO

A series of aldo-bis-indole derivatives (aldo-BINs) was prepared by aromatic C-alkylation reactions of aldoses and indole in acetic acid solution. Common monosaccharides such as glucose, mannose, galactose, fucose, xylose, rhamnose, ribose, arabinose and N-acetylglucosamine were smoothly derivatized to form the UV absorbing aldo-BINs. The use of a capillary electrophoretic method to separate these novel aldo-BIN derivatives was established. The capillary electrophoresis conditions were set by using borate buffer (100 mM) at high pH (pH 9.0). The limit of determination was assessed to be 25 nM. The enantioseparation of D, L-pairs of aldo-BINs based on chiral ligand-exchange capillary electrophoresis technology was also achieved by using modified hydroxypropyl-ß-cyclodextrin as the chiral selector in the presence of borate buffer. This aldose labeling method was applied successfully to the compositional and configurational analysis of saccharides, exemplified by a rapid and efficient method to simultaneously analyze the composition and configuration of saccharides from the medicinal herbs Cordyceps sinensis and Dendrobium huoshanense.


Assuntos
Boratos/química , Eletroforese Capilar/métodos , Indóis/química , Monossacarídeos/análise , Polissacarídeos/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Cordyceps/química , Ligantes , Estrutura Molecular , Extratos Vegetais/química , Estereoisomerismo
11.
J Lipid Res ; 52(3): 471-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21217100

RESUMO

A novel water-soluble polysaccharide fraction, CME-1, with a molecular mass of 27.6 kDa and containing mannose and galactose in a respective ratio of 4:6, was prepared from Cordyceps sinensis mycelia and identified by NMR and GC-MS. In the current study, we examined whether CME-1 has anti-inflammatory effects in RAW264.7 cells. The ability of CME-1 to inhibit H(2)O(2)-induced cell death in RAW264.7 cells was assessed by using an MTT assay and annexin V/propidium iodide double staining; we found that CME-1 protected cells against H(2)O(2)-induced injury. H(2)O(2)-induced intracellular oxidative stress and mitochondrial membrane depolarization were also diminished with CME-1 treatment. We evaluated the hydroxyl radical scavenging ability of CME-1 by using the DMPO-electron spin resonance technique, which indicated that CME-1 acts as an intracellular antioxidant in a concentration-dependent manner through a mechanism other than its scavenging activity. Activities of both neutral and acid sphingomyelinases (SMases) were assessed in vitro, and results showed that the CME-1 inhibited activities of both neutral and acid SMases in a concentration-dependent manner. CME-1 reduced H(2)O(2) treatment-elevated C16- and C18-ceramide levels measured by LC/MS/MS in RAW264.7 cells. Results suggest that CME-1 protects RAW264.7 cells against oxidative stress through inhibition of SMase activity and reduction of C16- and C18-ceramide levels.


Assuntos
Cordyceps/química , Citoproteção/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Micélio/química , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/farmacologia , Esfingomielina Fosfodiesterase/antagonistas & inibidores , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Ceramidas/metabolismo , Cordyceps/crescimento & desenvolvimento , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Peróxido de Hidrogênio/farmacologia , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Membranas Mitocondriais/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Solubilidade , Água/química
12.
Molecules ; 15(3): 1340-53, 2010 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20335985

RESUMO

A novel method for the conversion of unprotected and unmodified aldoses to aldo-imidazoles has been developed. Using iodine as a catalyst in acetic acid solution, a series of mono- and oligosaccharides, including those containing carboxyl and acetamido groups, undergo an oxidative condensation reaction with aromatic vicinal diamines at room temperature to give the corresponding aldo-imidazole products in high yields. No cleavage of the glycosidic bond occurs under the mild reaction conditions. The compositional analysis of saccharides is commonly realized by capillary electropheresis of the corresponding aldo-imidazole derivatives, which are easily synthesized by the reported iodine-promoted oxidative condensation. In addition, a series of aldo-imidazoles were determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to analyze molecular weight and ion intensity. The diamine-labeled saccharides showed enhanced signals in MALDI-TOF MS. The combined use of aldoimidazole derivatization and mass spectrometric analysis thus provides a rapid method for identification of saccharides, even when less than 1 pmol of saccharide is present in the sample. These results can be further applied to facilitate the isolation and analysis of novel saccharides.


Assuntos
Carboidratos/análise , Iodo/metabolismo , Naftalimidas/química , Catálise , Cromatografia Líquida de Alta Pressão , Eletroforese Capilar , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Oxirredução , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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