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1.
J Adhes Dent ; 26: 147-170, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785223

RESUMO

PURPOSE: To systematically review in-vitro studies that evaluated the influence of erbium laser pretreatment on dentin shear bond strength (SBS) and bond failure modes. MATERIALS AND METHODS: Electronic databases (PubMed, Cochrane Central, Embase, and Web of Science) were searched. Only in-vitro studies involving erbium laser irradiation of the dentin surface and SBS testing of the bonded resin block were included. The three common modes of bond failure (1. adhesive, 2. cohesive, and 3. mixed) were observed and analyzed. The network meta-analysis (NMA) was performed by Stata 15.0 software, the risk of bias was evaluated, and the certainty of the evidence was assessed by the Confidence in Network Meta-analysis (CINeMA). RESULTS: Forty studies with nine pretreatments (1. blank group: BL; 2. phosphoric acid etch-and-rinse: ER; 3. self-etch adhesive: SE; 4. Er:YAG laser: EL; 5. Er,Cr:YSGG laser: ECL; 6. ER+EL; 7. ER+ECL; 8. SE+EL; 9. SE+ECL) were included in this analysis. The NMA of SBS showed that ER+EL [SMD = 0.32, 95% CI (0.11, 0.98)] had the highest SBS next to ER, especially when using one of the 3M ESPE adhesives, followed by EL, ECL, SE and SE+EL. The Ivoclar Vivadent adhesives significantly increased the SBS of the ECL [SMD = 0.37, 95% CI (0.16,0.90)] and was higher than ER+EL [SMD = 0.25,95% CI (0.07,0.85)]. Finally, the surface under the cumulative ranking curve (SUCRA) value indicated that ER+EL (SUCRA = 71.0%) and EL (SUCRA = 62.9%) were the best treatments for enhancing dentin SBS besides ER. ER+EL (SUCRA = 85.3%), ER (SUCRA = 83.7%) and ER (SUCRA = 84.3%) had the highest probability of occurring in adhesive, cohesive and mixed failure modes, respectively. CONCLUSION: Er:YAG and Er,Cr:YSGG lasers improved dentin SBS compared to the blank group, especially when the acid etch-and-rinse pretreatment was combined with Er:YAG laser. Shear bond strength and failure mode do not appear to be directly related.


Assuntos
Colagem Dentária , Dentina , Lasers de Estado Sólido , Resistência ao Cisalhamento , Colagem Dentária/métodos , Lasers de Estado Sólido/uso terapêutico , Humanos , Metanálise em Rede , Adesivos Dentinários/química , Condicionamento Ácido do Dente , Análise do Estresse Dentário
2.
J Dent ; 146: 105026, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38679134

RESUMO

OBJECTIVES: To analyze the role of oxidative stress (OS) biomarkers in peri­implant diseases using a systematic review and meta-analysis approach. DATE: The review incorporated cross-sectional studies, randomized controlled trials, and case-control trials to evaluate the differences in OS biomarkers of peri­implant disease. SOURCES: A comprehensive literature search was conducted in electronic databases such as PubMed, Scopus, Embase, Web of Science, and CNKI, and no restrictions were applied during the search process. STUDY SELECTION: A total of 452 studies were identified, of which 18 were eligible for inclusion. Risk of bias and sensitivity analysis were assessed using Egger's test and funnel plots. RESULTS: We found that the levels of glutathione peroxidase (GSH-Px) in the peri­implant sulcus fluid (PISF) of patients with peri­implant diseases were significantly reduced (SMD = -1.40; 95 % CI = 1.70, -1.11; p < 0.001), while the levels of total myeloperoxidase (MPO) and malondialdehyde (MDA) were significantly increased (SMD = 0.46; 95 % CI = 0.12, 0.80; p = 0.008; SMD = 0.28; 95 % CI = 0.01, 0.56; p = 0.043). However, there were no significant differences of MPO concentration (SMD = 0.38; 95 % CI = -0.39, 1.15; p = 0.331) and superoxide dismutase (SOD)(SMD = -0.43; 95 % CI = -1.94, 1.07; p = 0.572) in PISF between peri­implant disease group and control group. Similarly, salivary MPO did not show significant differences (SMD = 1.62; 95 % CI = -1.01, 4.24; p = 0.227). CONCLUSIONS: Our results supported that the level of local OS biomarkers was closely related to peri­implant diseases. GSH-Px, total MPO and MDA may be PISF biomarkers with good capability to monitor the development of peri­implant disease. CLINICAL SIGNIFICANCE: This study found significant differences in the levels of local OS biomarkers (GSH-Px, total MPO, and MDA) between patients with peri­implant diseases and healthy subjects, which may be ideal candidate biomarkers for predicting and diagnosing peri­implant diseases.


Assuntos
Biomarcadores , Implantes Dentários , Glutationa Peroxidase , Malondialdeído , Estresse Oxidativo , Peri-Implantite , Peroxidase , Humanos , Biomarcadores/análise , Peroxidase/análise , Malondialdeído/análise , Malondialdeído/metabolismo , Peri-Implantite/metabolismo , Glutationa Peroxidase/análise , Glutationa Peroxidase/metabolismo , Líquido do Sulco Gengival/química
3.
PLoS One ; 19(3): e0298918, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451964

RESUMO

This study, conducted in China in November 2020, was aimed at exploring the variations in growth traits among different provenances and families as well as to select elite materials of Juglans mandshurica. Thus, seeds of 44 families from six J. mandshurica provenances in Heilongjiang and Jilin provinces were sown in the nursery and then transplanted out in the field. At the age of 5 years, seven growth traits were assessed, and a comprehensive analysis was conducted as well as selection of provenance and families. Analysis of variance revealed statistically significant (P < 0.01) differences in seven growth traits among different provenances and families, thereby justifying the pursuit of further breeding endeavors. The genetic coefficient of variation (GCV) for all traits ranged from 5.44% (branch angle) to 21.95% (tree height) whereas the phenotypic coefficient of variation (PCV) ranged from 13.74% (tapering) to 38.50% (branch number per node), indicating considerable variability across the traits. Further, all the studied traits except stem straightness degree, branch angle and branch number per node, showed high heritability (Tree height, ground diameter, mean crown width and tapering, over 0.7±0.073), indicating that the variation in these traits is primarily driven by genetic factors. Correlation analysis revealed a strong positive correlation (r > 0.8) between tree height and ground diameter (r = 0.86), tree height and mean crown width (r = 0.82), and ground diameter and mean crown width (r = 0.83). This suggests that these relationships can be employed for more precise predictions of the growth and morphological characteristics of trees, as well as the selection of superior materials. There was a strong correlation between temperature factors and growth traits. Based on the comprehensive scores in this study, Sanchazi was selected as elite provenance. Using the top-percentile selection criteria, SC1, SC8, DJC15, and DQ18 were selected as elite families. These selected families exhibit genetic gains of over 10% in tree height, ground diameter and mean crown width, signifying their significant potential in forestry for enhancing timber production and reducing production cycles, thereby contributing to sustainable forest management. In this study, the growth traits of J. mandshurica were found to exhibit stable variation, and there were correlations between these traits. The selected elite provenance and families of J. mandshurica showed faster growth, which is advantageous for the subsequent breeding and promotion of improved J. mandshurica varieties.


Assuntos
Juglans , Juglans/genética , Melhoramento Vegetal , Árvores , Florestas , China
4.
BMC Oral Health ; 23(1): 973, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057755

RESUMO

AIM: To evaluate the effects of root canal treatment (RCT) and post-crown restoration on stress distribution in teeth with periapical bone defects using finite element analysis. METHODOLOGY: Finite element models of mandibular second premolars and those with periapical bone defects (spherical defects with diameters of 5, 10, 15, and 20 mm) were created using digital model design software. The corresponding RCT and post-crown restoration models were constructed based on the different sizes of periapical bone defect models. The von Mises stress and tooth displacement distributions were comprehensively analyzed in each model. RESULTS: Overall analysis of the models: RCT significantly increased the maximum von Mises stresses in teeth with periapical bone defects, while post-crown restoration greatly reduced the maximum von Mises stresses. RCT and post-crown restoration slightly reduced tooth displacement in the affected tooth. Internal analysis of tooth: RCT dramatically increased the maximum von Mises stress in all regions of the tooth, with the most pronounced increase in the coronal surface region. The post-crown restoration balances the internal stresses of the tooth and is most effective in periapical bone defect - 20-mm model. RCT and post-crown restoration slightly reduced the tooth displacement in all regions of the affected tooth. CONCLUSIONS: Root canal treatment seemed not to improve the biomechanical state of teeth with periapical bone defects. In contrast, post-crown restoration might effectively balance the stress concentrations caused by periapical bone defects, particularly extensive ones.


Assuntos
Periodontite Periapical , Coroa do Dente , Humanos , Análise de Elementos Finitos , Cavidade Pulpar , Coroas , Periodontite Periapical/terapia
5.
BMC Oral Health ; 23(1): 980, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066540

RESUMO

BACKGROUND: Apical periodontitis directly affects the stress state of the affected tooth owing to the destruction of the periapical bone. Understanding the mechanical of periapical bone defects/tooth is clinically meaningful. In this study, we evaluate the effect of periapical bone defects on the stress distribution in teeth with periapical periodontitis using finite element analysis. METHODS: Finite element models of normal mandibular second premolars and those with periapical bone defects (spherical defects with diameters of 5, 10, 15, and 20 mm) were created using a digital model design software. The edges of the mandible were fixed and the masticatory cycle was simplified as oblique loading (a 400 N force loaded obliquely at 45° to the long axis of the tooth body) to simulate the tooth stress state in occlusion and analyze the von Mises stress distribution and tooth displacement distribution in each model. RESULTS: Overall analysis of the models: Compared to that in the normal model, the maximum von Mises stresses in all the different periapical bone defect size models were slightly lower. In contrast, the maximum tooth displacement in the periapical bone defect model increased as the size of the periapical bone defect increased (2.11-120.1% of increase). Internal analysis of tooth: As the size of the periapical bone defect increased, the maximum von Mises stress in the coronal cervix of the tooth gradually increased (2.23-37.22% of increase). while the von Mises stress in the root apical region of the tooth showed a decreasing trend (41.48-99.70% of decrease). The maximum tooth displacement in all parts of the tooth showed an increasing trend as the size of the periapical bone defect increased. CONCLUSIONS: The presence of periapical bone defects was found to significantly affect the biomechanical response of the tooth, the effects of which became more pronounced as the size of the bone defect increased.


Assuntos
Periodontite Periapical , Software , Humanos , Análise de Elementos Finitos , Estresse Mecânico , Dente Pré-Molar , Análise do Estresse Dentário
6.
Int J Mol Sci ; 23(21)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36362393

RESUMO

Korean pine (Pinus koraiensis Sieb. et Zucc.), as the main tree species in northeast China, has important economic and ecological values. Currently, supplementary light has been widely used in plant cultivation projects. However, the studies about different supplementary light sources on the growth and development of Korean pine are few. In this study, the one with no supplementary light was used as the control, and two kinds of light sources were set up: light-emitting diode (LED) and incandescent lamp, to supplement light treatment of Korean pine. The spectrum and intensity of these two light sources were different. The results showed that the growth and physiological-biochemical indicators were significantly different under different supplementary light treatments. The biomass of supplementary light treatment was significantly lower than the control. Compared with the control, IAA and GA were lower, and JA, ABA, ZT, and ETH were higher under supplementary light conditions. Photosynthetic parameters in supplementary light conditions were significantly lower than the control. Supplemental light induces chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid accumulation. From RNA-seq data, differentially expressed genes (DEGs) were observed in all the comparison groups, and there were 487 common DEGs. The expression levels of DEGs encoding transcription factors were also changed. According to GO and KEGG analysis, the plant hormone signal transduction, circadian rhythm-plant, and flavonoid biosynthesis pathways were the most enriched. These results provided a theoretical basis for the response of Korean pine to different supplementary lights.


Assuntos
Pinus , Pinus/genética , Transcriptoma , Clorofila A , Perfilação da Expressão Gênica , Árvores/genética , China
7.
Int J Mol Sci ; 23(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36076949

RESUMO

Light is one of the most important environmental cues that affects plant development and regulates its behavior. Light stress directly inhibits physiological responses and plant tissue development and even induces mortality in plants. Korean pine (Pinus koraiensis) is an evergreen conifer species widely planted in northeast China that has important economic and ecological value. However, the effects of light stress on the growth and development of Korean pine are still unclear. In this study, the effects of different shading conditions on physiological indices, molecular mechanisms and metabolites of Korean pine were explored. The results showed that auxin, gibberellin and abscisic acid were significantly increased under all shading conditions compared with the control. The contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoid also increased as the shading degree increased. Moreover, a total of 8556, 3751 and 6990 differentially expressed genes (DEGs) were found between the control and HS (heavy shade), control and LS (light shade), LS vs. HS, respectively. Notably, most DEGs were assigned to pathways of phytohormone signaling, photosynthesis, carotenoid and flavonoid biosynthesis under light stress. The transcription factors MYB-related, AP2-ERF and bHLH specifically increased expression during light stress. A total of 911 metabolites were identified, and 243 differentially accumulated metabolites (DAMs) were detected, among which flavonoid biosynthesis (naringenin chalcone, dihydrokaempferol and kaempferol) metabolites were significantly different under light stress. These results will provide a theoretical basis for the response of P. koraiensis to different light stresses.


Assuntos
Pinus , Carotenoides/metabolismo , Clorofila A/metabolismo , Flavonoides/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Pinus/metabolismo , Transcriptoma
8.
Front Plant Sci ; 13: 931578, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845684

RESUMO

Juglans mandshurica is a native tree species in Northeast China. Due to habitat destruction and human disturbance, its population size has sharply decreased. Currently, information on molecular markers of J. mandshurica is limited and cannot meet the needs of germplasm resource evaluation and molecular marker-assisted breeding of J. mandshurica. Based on transcriptomic data from three tissues (leaves, bark, and fruit pericarp), we developed expressed sequence tag-simple sequence repeats (EST-SSRs) for J. mandshurica, and 15 polymorphic EST-SSR primers were initially selected. The average number of alleles (Na), expected heterozygosity (He), and the polymorphic information content (PIC) at different loci were 18.27, 0.670, and 0.797, respectively. Population genetic diversity analysis revealed that the average Na, He, and Shannon information indices (I) for 15 J. mandshurica populations were 6.993, 0.670, and 1.455, respectively. Among them, population Hunchun exhibited the highest genetic diversity (Na = 7.933, He = 0.723, and I = 1.617), while population Heihe exhibited the lowest genetic diversity (Na = 4.200, He = 0.605, and I = 1.158). STRUCTURE analysis, neighbor-joining method cluster analysis, and principal coordinate analysis showed that the 343 individuals of J. mandshurica from 15 populations were clustered into three categories. Category 1 (green) had 147 individuals from eight populations in Qingyuan, Caohekou, Jian, Ningan, Yongji, Baishishan, Helong, and Maoershan; category 2 (blue) had 81 individuals from three populations in Hulin, Boli, and Sanchazi; and category 3 (red) had 115 individuals from four populations in Heihe, Hunchun, Fangzheng, and Liangshui. Analysis of molecular variance (AMOVA) showed that genetic variations among and within individuals accounted for 16.22% and 21.10% of the total genetic variation, respectively, indicating that genetic variations within populations were greater than genetic variations among populations. The average genetic differentiation coefficient (Fst) and gene flow (Nm) between different populations were 0.109 and 4.063, respectively, implying moderate levels of genetic differentiation and gene flow. Based on the genetic diversity characteristics of different populations, we proposed various genetic conservation strategies for J. mandshurica.

9.
Gigascience ; 112022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35764602

RESUMO

BACKGROUND: Manchurian walnut (Juglans mandshurica Maxim.) is a tree with multiple industrial uses and medicinal properties in the Juglandaceae family (walnuts and hickories). J. mandshurica produces juglone, which is a toxic allelopathic agent and has potential utilization value. Furthermore, the seed of J. mandshurica is rich in various unsaturated fatty acids and has high nutritive value. FINDINGS: Here, we present a high-quality chromosome-scale reference genome assembly and annotation for J. mandshurica (n = 16) with a contig N50 of 21.4 Mb by combining PacBio high-fidelity reads with high-throughput chromosome conformation capture data. The assembled genome has an estimated sequence size of 548.7 Mb and consists of 657 contigs, 623 scaffolds, and 40,453 protein-coding genes. In total, 60.99% of the assembled genome consists of repetitive sequences. Sixteen super-scaffolds corresponding to the 16 chromosomes were assembled, with a scaffold N50 length of 33.7 Mb and a BUSCO complete gene percentage of 98.3%. J. mandshurica displays a close sequence relationship with Juglans cathayensis, with a divergence time of 13.8 million years ago. Combining the high-quality genome, transcriptome, and metabolomics data, we constructed a gene-to-metabolite network and identified 566 core and conserved differentially expressed genes, which may be involved in juglone biosynthesis. Five CYP450 genes were found that may contribute to juglone accumulation. NAC, bZip, NF-YA, and NF-YC are positively correlated with the juglone content. Some candidate regulators (e.g., FUS3, ABI3, LEC2, and WRI1 transcription factors) involved in the regulation of lipid biosynthesis were also identified. CONCLUSIONS: Our genomic data provide new insights into the evolution of the walnut genome and create a new platform for accelerating molecular breeding and improving the comprehensive utilization of these economically important tree species.


Assuntos
Juglans , Cromossomos , Genoma , Juglans/genética , Lipídeos , Naftoquinonas
10.
Cell Death Dis ; 12(7): 676, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226522

RESUMO

Growing evidence has indicated that circular RNAs (circRNAs) play a pivotal role as functional RNAs in diverse cancers. However, most circRNAs involved in esophageal squamous cell carcinoma (ESCC) remain undefined, and the underlying molecular mechanisms mediated by circRNAs are largely unclear. Here, we screened human circRNA expression profiles in ESCC tissues and found significantly increased expression of hsa_circ_0000277 (termed circPDE3B) in ESCC tissues and cell lines compared to the normal controls. Moreover, higher circPDE3B expression in patients with ESCC was correlated with advanced tumor-node-metastasis (TNM) stage and dismal prognosis. Functional experiments demonstrated that circPDE3B promoted the tumorigenesis and metastasis of ESCC cells in vitro and in vivo. Mechanistically, bioinformatics analysis, a dual-luciferase reporter assay, and anti-AGO2 RNA immunoprecipitation showed that circPDE3B could act as a competing endogenous RNA (ceRNA) by harboring miR-4766-5p to eliminate the inhibitory effect on the target gene laminin α1 (LAMA1). In addition, LAMA1 was significantly upregulated in ESCC tissues and was positively associated with the aggressive oncogenic phenotype. More importantly, rescue experiments revealed that the oncogenic role of circPDE3B in ESCC is partly dependent on the miR-4766-5p/LAMA1 axis. Furthermore, bioinformatics analysis combined with validation experiments showed that epithelial-mesenchymal transition (EMT) activation was involved in the oncogenic functions of the circPDE3B-miR-4766-5p/LAMA1 axis in ESCC. Taken together, we demonstrate for the first time that the circPDE3B/miR-4766-5p/LAMA1 axis functions as an oncogenic factor in promoting ESCC cell proliferation, migration, and invasion by inducing EMT, implying its potential prognostic and therapeutic significance in ESCC.


Assuntos
Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Laminina/metabolismo , MicroRNAs/metabolismo , RNA Circular/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Transição Epitelial-Mesenquimal , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Laminina/genética , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica , RNA Circular/genética , Transdução de Sinais
11.
ACS Omega ; 6(5): 3875-3883, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33585766

RESUMO

In the present work, an efficient and stable WO X /MCM-41 solid acid catalyst was prepared by the wet impregnation method. The characterization of powder X-ray diffraction, transmission electron microscopy, ultraviolet-visible, H2 temperature-programmed reduction, X-ray photoelectron spectroscopy, NH3 temperature-programmed desorption, and N2 adsorption-desorption isotherms confirmed that the impregnation amount and calcination temperature of WO X speciation affected the dispersity and acidity of the resulting catalyst. This WO X /MCM-41 solid acid catalyst was subsequently applied in the ketalization reaction of glycerol and acetone to produce solketal. By catalyst screening and reaction condition optimization, WO X /MCM-41 obtained by impregnating 20 wt % and calcining at 350 °C exhibited the highest solketal yield and catalytic stability.

12.
ACS Omega ; 5(33): 20784-20791, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32875212

RESUMO

This work presented the microfluidic preparation of zeolite film in a capillary microchannel with different length-to-diameter ratios. In the quartz capillary with an inner diameter of 0.53 and 0.32 mm, Zeolite Socony Mobil-5 (ZSM-5) film was prepared by a continuous flow hydrothermal method. Considering the chemically inert surface of quartz capillary and the difficulty of preparing uniform and continuous zeolite film by conventional static synthesis, the ZSM-5 seed layer was precoated as active sites to induce film growth. The parameters of length-to-diameter ratio, seed coating, feed flow rate, and synthesis time were investigated. It revealed that the crystallinity of the ZSM-5 film was significantly affected by the capillary length-to-diameter ratio and seed coating in this flow system. The film morphology and thickness could be precisely controlled by adjusting the feed flow rate and synthesis time. This hydrogen form of the ZSM-5 (HZSM-5) film capillary microreactor was applied in the ketalization reaction of glycerol with acetone to produce solketal. The single-pass yield of solketal could reach ∼30% under mild conditions. This work provided a convenient stratagem of preparing zeolite catalytic coating or other support coatings in closed microchannels with a high length-to-diameter ratio and the potential application in valuable transformation of biomass glycerol.

13.
Genes (Basel) ; 11(6)2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575537

RESUMO

Combining phenotypic and genetic characteristics in a genetic variation study is of paramount importance to effectively orient the selection of producers' elite trees in a seed orchard. In total, 28 phenotypic characteristics and 16 microsatellite loci were used to analyze the clonal genetic variation, to characterize the genetic diversity, and to refine the genetic classifications of 110 Pinus koraiensis clones grown in the Naozhi orchard in northeastern China. All clones were significantly different in most traits. Most of the phenotypic characteristics showed great genetic variation among clones, while the genotypic differentiation was weak between the selection sites of clones. The SSR markers showed a relatively high level of genetic diversity (Na = 4.67 ± 0.43, Ne = 2.916 ± 0.18, I = 1.15 ± 0.07, Ho = 0.69 ± 0.04, He = 0.62 ± 0.02, and mean polymorphic information content (PIC) of 0.574), with higher heterozygosity as an indication of a lower probability of inbreeding events in the orchard. Despite weak correlation coefficients between dissimilarity matrices (r(A/B), range equal to 0.022, p-value < 0.001), the genetic and phenotypic classifications congruently subdivided all the clones into three major groups. The patterns of phenotypic trait variations and genetic diversity are valuable to effectively select materials in breeding programs of P. koraiensis.


Assuntos
Variação Biológica da População/genética , Variação Genética/genética , Repetições de Microssatélites/genética , Pinus/genética , China , Genótipo , Heterozigoto , Fenótipo , Sementes/genética
14.
Insect Sci ; 24(4): 543-558, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26573759

RESUMO

Olfaction is primarily mediated by highly specified olfactory receptors (ORs). Here, we cloned and identified an olfactory receptor, named SlituOR1 (Genbank no. JN835269), from Spodoptera litura and found evidence that it is a candidate pheromone receptor. It exhibited male-biased expression in the antennae, where it was localized at the base of sensilla trichoidea, the antennal sensilla mainly responsive to pheromones in moths. Conserved orthologues of this receptor, found among known pheromone receptors within the Lepidoptera, and SlituOR1 were placed among a clade of candidate pheromone receptors in a phylogeny tree of insect OR gene sequences. SlituOR1 showed differential expression in S. litura populations attracted to traps baited with different ratios of the two sex pheromone components (9Z,11E)-tetradecadienyl acetate (Z9E11-14:OAc) and (9Z,12E)-tetradecadienyl acetate (Z9E12-14:OAc). Knocking down of SlituOR1 by RNA interference reduced the electroantennogram (EAG) response to Z9E11-14:OAc, and this result is consistent with the field trapping experiment. We infer that variation in transcription levels of olfactory receptors may modulate sex pheromone perception in male moths and could provide some of the flexibility required to maintain the functionality of communication with females when a population is adapting to a new niche and reproductive isolation becomes an advantage.


Assuntos
Sensilas/metabolismo , Atrativos Sexuais/farmacologia , Spodoptera/genética , Spodoptera/fisiologia , Animais , Antenas de Artrópodes/efeitos dos fármacos , Antenas de Artrópodes/metabolismo , Fenômenos Eletrofisiológicos , Feminino , Perfilação da Expressão Gênica , Proteínas de Insetos/genética , Masculino , Filogenia , Interferência de RNA , Receptores de Feromônios/genética , Sensilas/efeitos dos fármacos , Análise de Sequência de DNA , Atrativos Sexuais/química
15.
Sci Rep ; 6: 20672, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26857592

RESUMO

The assembly of a fluorescent pentiptycene-based ligand with copper ion resulted in the formation of a 3D porous metal-organic framework (UPC-21) based on well-known paddlewheel SBUs. UPC-21 exhibits selective adsorption of CO2 over CH4 and N2 at 273 K and 295 K, C2H2 over CH4 at 273 K. The most significant performance of UPC-21 is its highly efficient detection of NACs such as 4-NP, 1,4-DNB, NB, and 1,3-DNB with the calculated quenching constants, Ksv, being 3.097 × 10(6), 1.406 × 10(6), 4.420 × 10(5), and 1.498 × 10(5 )M(-1) for 4-NP, 1,4-DNB, NB, 1,3-DNB, respectively, which keeps a record on the fluorescence detection of NACs. This is the first porous Cu(II) MOF that exhibits fluorescent detection of NACs with high sensitivities.

16.
PLoS One ; 10(9): e0137588, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26340537

RESUMO

The α7nicotinic receptor (nAChR) is a major subtype of the nAChRs in the central nervous system, and the receptor plays an important role in brain function. In the dbSNP database, there are 55 single nucleotide polymorphisms (SNPs) that cause missense mutations of the human α7nAChR in the coding region. In this study, we tested the impact of 14 SNPs that cause missense mutations in the agonist binding site or the coupling region between binding site and channel gate on the receptor function. The wild type or mutant receptors were expressed or co-expressed in Xenopus oocytes, and the agonist-induced currents were tested using two-electrode voltage clamp. Our results demonstrated that 6 mutants were nonfunctional, 4 mutants had reduced current expression, and 1 mutants altered ACh and nicotine efficacy in the opposite direction, and one additional mutant had slightly reduced agonist sensitivity. Interestingly, the function of most of these nonfunctional mutants could be rescued by α7nAChR positive allosteric modulator PNU-120596 and agonist-PAM 4BP-TQS. Finally, when coexpressed with the wild type, the nonfunctional mutants could also influence the receptor function. These changes of the receptor properties by the mutations could potentially have an impact on the physiological function of the α7nAChR-mediated cholinergic synaptic transmission and anti-inflammatory effects in the human SNP carriers. Rescuing the nonfunctional mutants could provide a novel way to treat the related disorders.


Assuntos
Mutação de Sentido Incorreto , Oócitos/efeitos dos fármacos , Polimorfismo de Nucleotídeo Único , Receptor Nicotínico de Acetilcolina alfa7/genética , Acetilcolina/farmacologia , Regulação Alostérica , Animais , Relação Dose-Resposta a Droga , Expressão Gênica , Humanos , Isoxazóis/química , Isoxazóis/farmacologia , Modelos Moleculares , Nicotina/farmacologia , Agonistas Nicotínicos/química , Agonistas Nicotínicos/farmacologia , Oócitos/citologia , Oócitos/metabolismo , Técnicas de Patch-Clamp , Compostos de Fenilureia/química , Compostos de Fenilureia/farmacologia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Quinolinas/química , Quinolinas/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Transgenes , Xenopus laevis , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
17.
PLoS One ; 10(6): e0131407, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26126192

RESUMO

Olfaction is primarily mediated by highly specific olfactory receptors (ORs), a subfamily of which are the pheromone receptors that play a key role in sexual communication and can contribute to reproductive isolation. Here we cloned and identified an olfactory receptor, SlituOR3 (Genbank NO. JN835270), from Spodoptera litura, to be the candidate pheromone receptor. It exhibited male-biased expression in the antennae, where they were localized at the base of sensilla trichoidea. Conserved orthologues of these receptors were found amongst known pheromone receptors within the Lepidoptera, and SlituOR3 were placed amongst a clade of candidate pheromone receptors in a phylogeny tree of insect ORs. SlituOR3 is required for the EAG responses to both Z9E11-14:OAc and Z9E12-14:OAc SlituOR3 showed differential expression in S. litura populations attracted to traps baited with a series of sex pheromone blends composed of different ratios of (9Z,11E)-tetradecadienyl acetate (Z9E11-14:OAc) and (9Z,12E)-tetradecadienyl acetate (Z9E12-14:OAc). The changes in the expression level of SlitOR3 and antennal responses after SlitOR3 silencing suggested that SlitOR3 is required for the sex pheromone signaling. We infer that variation in transcription levels of olfactory receptors may modulate sex pheromone perception in male moths and could affect both of pest control and monitoring efficiency by pheromone application after long time mass trapping with one particular ratio of blend in the field.


Assuntos
Proteínas de Insetos/genética , Receptores Odorantes/genética , Receptores de Feromônios/genética , Spodoptera/genética , Sequência de Aminoácidos , Animais , Antenas de Artrópodes/fisiologia , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Feminino , Inativação Gênica , Genes de Insetos , Proteínas de Insetos/química , Proteínas de Insetos/fisiologia , Masculino , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Receptores Odorantes/química , Receptores Odorantes/fisiologia , Receptores de Feromônios/química , Receptores de Feromônios/fisiologia , Homologia de Sequência de Aminoácidos , Atrativos Sexuais/fisiologia , Spodoptera/fisiologia
18.
Nanoscale ; 4(18): 5646-50, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22869008

RESUMO

Plasmonic shaped AgX:Ag (X = Cl, Br) nanoparticles have been synthesized by a facile and versatile glycerol-mediated solution route. The as-prepared AgX:Ag nanoparticles exhibit regular shapes, i.e., cube-tetrapod-like AgCl:Ag nanoparticles and AgBr:Ag nanoplates. Compared with the pristine AgX, AgX:Ag nanocomposites display stronger absorption in the visible region due to the surface plasmon resonance of silver nanoparticles. The calculation of bandgaps and band positions indicates the as-achieved AgX:Ag nanoparticles can be used as a class of potential photocatalyst for the reduction of CO(2). For example, reduction of CO(2) under visible light irradiation with the assistance of the anisotropic AgX:Ag nanoparticles yields as much as 100 µmol methanol in the products. Furthermore, the AgX:Ag nanoparticles can maintain its structure and activity after 3 runs of reactions. Therefore, the present route opens an avenue to acquire plasmonic photocatalysts for conversion of CO(2) into useful organic compounds.


Assuntos
Dióxido de Carbono/química , Luz , Nanopartículas Metálicas/química , Metanol/química , Prata/química , Catálise , Glicerol/química , Oxirredução , Ressonância de Plasmônio de Superfície
19.
Inorg Chem ; 50(7): 2844-50, 2011 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-21361391

RESUMO

Li(8)ZrO(6) contains a high lithium content and may bear a great ability of CO(2) absorption, yet the reports about the properties of CO(2) absorption on Li(8)ZrO(6) are few to date for its difficulty in production. In this paper, high-purity Li(8)ZrO(6) is synthesized via a three-step calcination method combined with an effective lithium source and a suitable initial Li/Zr molar ratio. The produced Li(8)ZrO(6) possesses a great CO(2) absorption capacity of about 53.98 wt % at 998 K, which could be well-maintained in a wide range of CO(2) partial pressures of 0.1-1.0 bar although it decreased gradually during the multicycle process of CO(2) absorption-desorption in a 10% CO(2) feed stream because of the high working temperature. These properties imply that Li(8)ZrO(6) may be a new option for high-temperature CO(2) capture applied in industrial processes such as a steam methane reformer.

20.
Artigo em Inglês | MEDLINE | ID: mdl-20529716

RESUMO

In this paper we theoretically and experimentally present a nonresonant vibration energy harvesting device based on the shear mode of 0.71Pb(Mg(1/3)Nb(2/3))O3-0.29PbTiO3 single crystals. The electrical properties of the energy harvesting device were evaluated using an analytical method. Good consistency was obtained between the analytical and experimental results. Under a mass load of 200 g, a peak voltage of 11.3 V and maximum power of 0.70 mW were obtained at 500 Hz when connecting a matching load resistance of 91 komega. A high output could always be obtained within a very wide frequency range. The results demonstrate the potential of the device in energy harvesting applied to low-power portable electronics and wireless sensors.

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