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In this work, the structural, electronic and optical properties of germanene and ZnSe substrate nanocomposites have been investigated using first-principles calculations. We found that the large direct-gap ZnSe semiconductors and zero-gap germanene form a typical orbital hybridization heterostructure with a strong binding energy, which shows a moderate direct band gap of 0.503 eV in the most stable pattern. Furthermore, the heterostructure undergoes semiconductor-to-metal band gap transition when subjected to external out-of-plane electric field. We also found that applying external strain and compressing the interlayer distance are two simple ways of tuning the electronic structure. An unexpected indirect-direct band gap transition is also observed in the AAII pattern via adjusting the interlayer distance. Quite interestingly, the calculated results exhibit that the germanene/ZnSe heterobilayer structure has perfect optical absorption in the solar spectrum as well as the infrared and UV light zones, which is superior to that of the individual ZnSe substrate and germanene. The staggered interfacial gap and tunability of the energy band structure via interlayer distance and external electric field and strain thus make the germanene/ZnSe heterostructure a promising candidate for field effect transistors (FETs) and nanoelectronic applications.
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Acetylcholinesterase (AChE, EC 3.1.1.7) is a key enzyme in terminating synaptic transmission. We knocked down the expression of Csace1 or Csace2 using chemically synthesized small interfering RNAs (siRNAs) designed from divergent regions. The mRNA abundance of the two ace genes was reduced to 50-70% of control levels. The enzyme activities were decreased to 40-70%. Silencing of Csace1 or Csace2 resulted in a ~25% mortality rate. Knockdown of Csace1 had major effects on larval growth inhibition and resulted in reduced larval weight and length, malformation and motor disability, whereas silencing of Csace2 had only minor effects. These results suggested that both AChE-1 and AChE-2 have important roles in maintaining life in this insect and indicated that AChE-1 might have nontypical functions in regulating larval growth and motor ability.
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Acetilcolinesterase/genética , Mariposas/genética , Atividade Motora/genética , Interferência de RNA , Acetilcolinesterase/metabolismo , Animais , Técnicas de Silenciamento de Genes , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , RNA Interferente PequenoRESUMO
The article "MOTS-c accelerates bone fracture healing by stimulating osteogenesis of bone marrow mesenchymal stem cells via positively regulating FOXF1 to activate the TGF-ß pathway, by F.-B. Weng, L.-F. Zhu, J.-X. Zhou, Y. Shan, Z.-G. Tian, L.-W. Yang, published in Eur Rev Med Pharmacol Sci 2019; 23 (24): 10623-10630-DOI: 10.26355/eurrev_201912_19759-PMID: 31858528" has been withdrawn from the authors due to inaccuracies during the process of organizing the images. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/19759.
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OBJECTIVE: To elucidate the function of MOTS-c in accelerating bone fracture healing by inducing BMSCs differentiation into osteoblasts, as well as its potential mechanism. MATERIALS AND METHODS: Primary BMSCs were extracted from rats and induced for osteogenesis. The highest dose of MOTS-c that did not affect BMSCs proliferation was determined by CCK-8 assay. After 7-day osteogenesis, the relative levels of ALP, Bglap, and Runx2 in MOTS-c-treated BMSCs influenced by FOXF1 were examined. ALP staining and alizarin red S staining in BMSCs were performed as well. The interaction between FOXF1 and TGF-ß was analyzed by ChIP assay. At last, rescue experiments were performed to uncover the role of FOXF1/TGF-ß axis in MOTS-c-induced osteogenesis. RESULTS: 1 µM MOTS-c was the highest dose that did not affect BMSCs proliferation. MOTS-c treatment upregulated the relative levels of ALP, Bglap, and Runx2, and stimulated mineralization ability in BMSCs, which were attenuated by the silence of FOXF1. TGF-ß was proved to interact with FOXF1, and its level was positively mediated by FOXF1. The silence of FOXF1 attenuated the accelerated osteogenesis and TGF-ß upregulation in BMSCs because of MOTS-c induction, and these trends were further reversed by the overexpression of TGF-ß. CONCLUSIONS: MOTS-c treatment markedly induces osteogenesis in BMSCs. During MOTS-c-induced osteogenic progression, the upregulated FOXF1 triggers the activation of TGF-ß pathway, thus accelerating bone fracture healing.
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Consolidação da Fratura , Regulação da Expressão Gênica/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Proteínas Mitocondriais/farmacologia , Osteogênese/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Células Cultivadas , Regulação para Baixo , Consolidação da Fratura/genética , Consolidação da Fratura/imunologia , Regulação da Expressão Gênica/imunologia , Inativação Gênica , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , Osteogênese/imunologia , Cultura Primária de Células , Ratos , Transdução de Sinais , Fator de Crescimento Transformador beta/genética , Regulação para CimaRESUMO
AIM: Early prosthodontic treatment for cases of ectodermal dysplasia (ED) is usually difficult because of oligodontia, undeveloped alveolar ridges, and the young age of the patients. Although some cases of prosthetic management of ED patients have been reported in the literature, there have been few cases about prosthetic treatment in children younger than 5 years of age. CASE REPORT: This case report presents early prosthetic oral rehabilitation of 2 twin sisters with ectodermal dysplasia and severe hypodontia in the primary dentition. Fixed partial dentures with bands retained on deciduous molars were fabricated when the girls were 3 years old. New flexible removable partial dentures were made when the girls turned 6 years to accommodate the ongoing alveolar development. After the dental treatment, the two girls' aesthetics, phonetics, and chewing functions all improved significantly, which in turn raised the girls' self-esteem and increased their overall quality of life. CONCLUSION: These two cases demonstrated that properly timed and managed early prosthodontic intervention can improve the overall life quality of young patients with ectodermal dysplasia.
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Anodontia , Prótese Parcial Removível , Displasia Ectodérmica , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Prostodontia , Qualidade de Vida , Adulto JovemRESUMO
OBJECTIVE: To screen the gene mutation in beta and gamma subunits of the epithelial sodium channel (ENaC) of a Chinese family, some of whose members are clinically diagnosed as suffering from Liddle syndrome. METHODS: Twelve family members were recruited to the study. Among them, two brothers had been clinically diagnosed as suffering from Liddle syndrome. Peripheral blood samples were collected from all members of the family and total genomic DNA was prepared for genetic analysis. Polymerase chain reaction (PCR) was used for amplifying the last exon of beta (codon 513-673) and gamma (codon 503-632) subunits of the ENaC gene. PCR products were purified and subjected to a direct DNA sequence analysis. RESULTS: Genetic analysis of the beta ENaC gene revealed a missense mutation of CCC to CTC at codon 616 in four middle-aged men of the second generation and one young woman of the third generation. There was no mutation of the gamma ENaC gene in any of the individuals examined. CONCLUSION: Through direct DNA sequencing analysis, we diagnosed the disease present in five members of a Chinese family as Liddle syndrome, and excluded it in some other young offspring suffering from the monogenic disease. Our results provide further evidence that Pro616 is a critical amino acid that has a key role in the inhibition of sodium channel activity.
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Aldosterona/metabolismo , Hipertensão/genética , Hipopotassemia/genética , Renina/sangue , Canais de Sódio/genética , Adolescente , Adulto , Idoso , Sequência de Bases/genética , Criança , DNA/genética , Canais Epiteliais de Sódio , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Linhagem , Isoformas de Proteínas/genética , SíndromeRESUMO
The total detectable rate of Helicobacter pylori (HP) of 485 patients suffering from gastric diseases was 59.6%. The HP in gastric mucosa of chronic atrophic gastritis (CAG) patients was separated from the cell culture in vitro and transferred successively. The mice were perfused with exciccate alum, and the rabbits with aspirin to injure their gastric mucosa, then HP was perfused. Result showed that the change of experimental animals was identical with that of CAG patients by means of bacteriological and pathological examination. It revealed that HP was in agreement with Robert Koch's three principles about pathogenic bacteria. According to the bacterial infectious hypothesis of CAG, 53 Chinese medicinal herbs and prescriptions were investigated with bacteriostatic test. Panax notogenseng and Magnolia officinalis were discovered to be sensitive, Prunus mume and Corydalis yanhusuo were moderate sensitive, and Coptis chinensis and Rheum palmatum highly sensitive to HP. Decoction of Clearing up the Heat and Relieving the Blood Stasis and No.2 recipe of Huowei were used to treat 70 CAG patients with Stomach Heat Syndrome. The effective rate of gastroscopic examination was 85.7%, that of pathological study was 80%. In comparing with the group of Shanjiu Weitai, there was significant difference between the traditional Chinese medicine treated group and Shanjiu Weitai control group, the former being markedly better.
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Medicamentos de Ervas Chinesas/uso terapêutico , Gastrite Atrófica/microbiologia , Gastrite Atrófica/prevenção & controle , Infecções por Helicobacter , Helicobacter pylori , Adolescente , Adulto , Idoso , Animais , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Gastrite Atrófica/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , CoelhosRESUMO
A proof of concept integrating binary p-n heterojunctions into a semiconductor hybrid photocatalyst is demonstrated by non-covalent doping of graphite-like carbon nitride (g-C3N4) with ultrathin GO and MoS2 nanosheets using a facile sonochemical method. In this unique ternary hybrid, the layered MoS2 and GO nanosheets with a large surface area enhance light absorption to generate more photoelectrons. On account of the coupling between MoS2 and GO with g-C3N4, the ternary hybrid possesses binary p-n heterojunctions at the g-C3N4/MoS2 and g-C3N4/GO interfaces. The space charge layers created by the p-n heterojunctions not only enhance photogeneration, but also promote charge separation and transfer of electron-hole pairs. In addition, the ultrathin MoS2 and GO with high mobility act as electron mediators to facilitate separation of photogenerated electron-hole pairs at each p-n heterojunction. As a result, the ternary hybrid photocatalyst exhibits improved photoelectrochemical and photocatalytic activity under visible light irradiation compared to other reference materials. The results provide new insights into the large-scale production of semiconductor photocatalysts.
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From the perspective of bond relaxation and bond vibration, we have formulated the Raman phonon relaxation of graphene, under the stimuli of the number-of-layers, the uni-axial strain, the pressure, and the temperature, in terms of the response of the length and strength of the representative bond of the entire specimen to the applied stimuli. Theoretical unification of the measurements clarifies that: (i) the opposite trends of the Raman shifts, which are due to the number-of-layers reduction, of the G-peak shift and arises from the vibration of a pair of atoms, while the D- and the 2D-peak shifts involve the z-neighbor of a specific atom; (ii) the tensile strain-induced phonon softening and phonon-band splitting arise from the asymmetric response of the C(3v) bond geometry to the C(2v) uni-axial bond elongation; (iii) the thermal softening of the phonons originates from bond expansion and weakening; and (iv) the pressure stiffening of the phonons results from bond compression and work hardening. Reproduction of the measurements has led to quantitative information about the referential frequencies from which the Raman frequencies shift as well as the length, energy, force constant, Debye temperature, compressibility and elastic modulus of the C-C bond in graphene, which is of instrumental importance in the understanding of the unusual behavior of graphene.
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Carbono/química , Grafite/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Análise Espectral Raman/métodos , Sítios de Ligação , Força Compressiva , Elasticidade , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração , Temperatura de TransiçãoRESUMO
Lanthanide (Ln3+) doped KGdF4 (Ln=Yb3+, Er3+, Ho3+, Tm3+) nanocrystals with a mean diameter of approximately 12 nm were synthesized by a hydrothermal method using oleic acid as a stabilizing agent at 180 °C. The nanocrystals crystallize in the cubic phase as α-NaGdF4. When excited by a 980 nm laser, these Ln3+ doped nanocrystals exhibit multicolor up-conversion (UC) emissions in red, yellow, blue and white. The calculated color coordinates demonstrate that white UC emission (CIE-X=0.352, CIE-Y=0.347) can be obtained by varying the dopant concentrations in the Yb3+/Ho3+/Tm3+ triply-doped nanocrystals to yield different RGB emission intensities. The measured field dependence of magnetization (M-H curves) of the KGdF4 nanocrystals shows their paramagnetic characteristics that can be ascribed to the non-interacting localized nature of the magnetic moment of Gd3+ ions. Moreover, low temperature thermal treatment can enhance UC properties, magnetization and magnetic mass susceptibility of Ln3+ doped KGdF4 nanocrystals. The multifunctional Ln3+ doped KGdF4 nanocrystals have potential applications in color displays, bioseparation, and optical-magnetic dual modal nanoprobes in biomedical imaging.
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Elementos da Série dos Lantanídeos/química , Magnetismo , Nanopartículas/química , Gadolínio/química , Hólmio/química , Nanopartículas/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Túlio/química , Difração de Raios X , Itérbio/químicaRESUMO
Highly ordered NiO coated Si nanowire array films are fabricated as electrodes for a high performance lithium ion battery via depositing Ni on electroless-etched Si nanowires and subsequently annealing. The structures and morphologies of as-prepared films are characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. When the potential window versus lithium was controlled, the coated NiO can be selected to be electrochemically active to store and release Li+ ions, while highly conductive crystalline Si cores function as nothing more than a stable mechanical support and an efficient electrical conducting pathway. The hybrid nanowire array films exhibit superior cyclic stability and reversible capacity compared to that of NiO nanostructured films. Owing to the ease of large-scale fabrication and superior electrochemical performance, these hybrid nanowire array films will be promising anode materials for high performance lithium-ion batteries.
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Fontes de Energia Elétrica , Eletrodos , Lítio/química , Membranas Artificiais , Nanoestruturas/química , Níquel/química , Silício/química , Cristalização/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Íons , Nanoestruturas/ultraestrutura , Nanotecnologia/instrumentação , Tamanho da PartículaRESUMO
An analytical form connecting the energy shift of Raman modes directly to the bonding identities (order, nature, length, energy) of a specimen and the response of the bonding identities to the applied stimuli of temperature and pressure was presented for a deeper understanding of the atomistic origin of the ZnO Raman shift. Theoretical reproduction based on the BOLS correlation theory [Sun, C. Q. Prog. Solid State Chem. 2007, 35, 1] and the local bond average (LBA) approach [Sun, C. Q. Prog. Mater. Sci. 2009, 54, 179] of the measurements revealed that the thermally softened ZnO Raman modes arise from bond expansion and bond weakening due to vibration and that the pressure-stiffened Raman modes result from bond compression and bond strengthening due to mechanical work hardening. The developed approach could be useful in generalizing the lattice dynamics directly to the process of vibration and relaxation of a representative bond of the specimen under external stimuli.
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The objective of this study was to determine the effects of the naked plasmid DNA encoding vascular endothelial growth factor (VEGF) on the survival of random flaps on rats. Thirty Sprague-Dawley rats whose random flaps were elevated on the back were randomised into three groups of 10 animals each. In the experimental group, the naked plasmid DNA encoding VEGF was injected directly into the panniculus carnosus of the flap. In the two control groups, either control plasmid DNA or physiologic saline was injected. After 7 days, the flaps were evaluated with the following devices: RT-PCR for the expression of VEGF gene, immunohistochemistry for the expression of VEGF protein, histology for vascular density, single photon emission computerised tomography for RBC in the flap, and image analysis for flap survival area. Notably increased expressions of VEGF mRNA and VEGF protein were found in the treatment group. Vascular density was markedly more increased in the treatment group than those in the two control groups (P < 0.01). Compared with the two control groups, the flap treated with VEGF plasmid DNA showed a more significantly enhanced tissue viability: 87 +/- 5 versus 47 +/- 6% for the control plasmid DNA group and 46 +/- 5% for the saline group (P < 0.01). Our results indicated that the VEGF gene therapy was able to enhance the survival of random pattern flaps by inducing angiogenesis.
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Terapia Genética/métodos , Retalhos Cirúrgicos/irrigação sanguínea , Fatores de Crescimento do Endotélio Vascular/genética , Animais , Modelos Animais de Doenças , Feminino , Expressão Gênica , Sobrevivência de Enxerto , Injeções Intramusculares , Neovascularização Fisiológica , Plasmídeos , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Tomografia Computadorizada de Emissão de Fóton Único , Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
OBJECTIVE: This study showed that the creep value of gallium alloy is higher than that of amalgam,but it was within the limits permitted by ISO.It was suggested that the poor handing characteristics of gallium alloy may make it difficult to use in clinic.So,if gallium alloy could use in the clinic or not,according to it's clinical handling characteristic.
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This paper described how to use hemorheology to observe the oral and maxillofacial inflammation.60 cases were reported,and 60 normal cases as control group.It revealed that etap of the oral maxillofacial inflammation were much higher than that of normal person(P<0.01),etab,etab-1/H,ESR,FA of the oral maxillofacial inflammation were higher than that of normal person(P<0.05).Because the disease belongs to the spectrum of blood stasis.The treatment method of the promoting blood circulation and removing blood stasis can be used in additional to the normal remedy.
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The adhesion of plaque on dental restorative between gallium alloy and amalgam alloy were compared.The results showed that plaque index and plaque account of gallium alloy was higher than those of amalgam,there was statistically significance(P<0.01).It was possible that secondary caries of gallium alloy's restorative may be higher than those of amalgam.One the other hand,the surface of restorative polished was necessary to improve the adhesion of plaque and to prevent the secondary caries.
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In this study we used light cured resin,opaque resin and composite resin/masking agent to bond 24 teeth in vitro and then we tested their bonding stress.We also used these three materials to treat 240 tetracycline stained teeth in clinic.After half a year,one year,two years follow-up we found:in vitro study,the highest stress of composite resin is 144.3kG/cm(2).There is no significant difference in statistics among these three materials if we used the masking agent or opaque resin or not.In clinical follow-up,there is no significant difference in shed,partial shed,margin stain,gingival inflammation,and unsatisfied rate in three groups.The author believed the masking agent or opaque resin has no influence on the stress of resin restoration.So when we treated tetracycline stained teeth,we could choose it to increase aesthetic feeling.
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Undecaprenyl pyrophosphate synthase (UPPs) catalyzes condensation of eight molecules of isopentenyl pyrophosphate with farnesyl pyrophosphate to yield C(55)-undecaprenyl pyrophosphate. We have mutated the aspartates and glutamates in the five conserved regions (I to V) of UPPs protein sequence to evaluate their effects on substrate binding and catalysis. The mutant enzymes including D26A, E73A, D150A, D190A, E198A, E213A, D218A, and D223A were expressed and purified to great homogeneity. Kinetic analyses of these mutant enzymes indicated that the substitution of D26 in region I with alanine resulted in a 10(3)-fold decrease of k(cat) value compared to wild-type UPPs. Its IPP K(m) value has only minor change. The mutagenesis of D150A has caused a much lower IPP affinity with IPP K(m) value 50-fold larger than that of wild-type UPPs but did not affect the FPP K(m) and the k(cat). The E213A mutant UPPs has a 70-fold increased IPP K(m) value and has a 100-fold decreased k(cat) value compared to wild-type. These results suggest that D26 of region I is critical for catalysis and D150 in region IV plays a significant role of IPP binding. The E213 residue in region V is also important in IPP binding as well as catalysis. Other mutant UPPs enzymes in this study have shown no significant change (<5-fold) of k(cat) with exception of E73A and D218A. Both enzymes have 10-fold lower k(cat) value relative to wild-type UPPs.
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Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Ácido Aspártico/genética , Sequência Conservada/genética , Escherichia coli/enzimologia , Escherichia coli/genética , Ácido Glutâmico/genética , Mutagênese Sítio-Dirigida , Alquil e Aril Transferases/biossíntese , Alquil e Aril Transferases/isolamento & purificação , Sequência de Aminoácidos , Sítios de Ligação/genética , Catálise , Cinética , Dados de Sequência Molecular , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Especificidade por Substrato/genéticaRESUMO
A new chiral ligand 6, 6'-dihydroxy-5, 5'-biquinoline (BIQOL, 2) was prepared via Cu2+ mediated coupling. The resolution was carried out by separating the corresponding ditrifluomethanesulfonate on chiral column. When applied to the enantioselective addition of diethylzinc to aromatic aldehydes, this ligand induced the reaction with enantioselectivity equivalent to that induced by BINOL. The effects of solvent and reaction temperature on enantioselectivity were also studied.