RESUMO
The Casparian strip (CS) is a cell wall modification made of lignin that functions as an apoplastic barrier in the root endodermis to restrict nutrient and water transport between the soil and stele. CS formation is affected by nutritional conditions, and its physiological roles have been discussed. This study found that low K condition affects CS permeability, lignin deposition, and MYB36 mRNA accumulation. To understand the mechanism underlying these findings, we focused on nitric oxide (NO). NO is known to act as a signaling molecule and participates in cell wall synthesis, especially for lignin composition. However, the mechanism by which NO affects lignin deposition and corrects CS formation in the plant roots remains unclear. Through combining fluorescent observation with histological stains, we demonstrated that the root endodermal cell lignification response to low-potassium (K) conditions is mediated by NO through the MYB36-associated lignin-polymerizing pathway. Furthermore, we discovered the noteworthy ability of NO to maintain nutrient homeostasis for adaptation to low K conditions by affecting the correct apoplastic barrier formation of CS. Collectively, our results suggest that NO is required for the lignification and apoplastic barrier formation in the root endodermis during adaptation to low K conditions, which revealing the novel physiological roles of CS under low nutrient conditions and making a significant contribution to CS biology.
Assuntos
Arabidopsis , Arabidopsis/genética , Óxido Nítrico/metabolismo , Lignina/metabolismo , Raízes de Plantas/metabolismo , Parede Celular/metabolismo , Diferenciação CelularRESUMO
Stimuli-responsive adhesives with on-demand adhesion capabilities are highly advantageous for facilitating wound healing. However, the triggering conditions of stimuli-responsive adhesives are cumbersome, even though some of them are detrimental to the adhesive and adjacent natural tissues. Herein, a novel stimuli-responsive adhesive called shear-stiffening adhesive (SSA) has been created by constructing a poly(diborosiloxane)-based silicone network for the first time, and SSA exhibits a rate-responsive adhesion behavior. Furthermore, we introduced bactericidal factors (PVP-I) into SSA and applied it as a wound dressing to promote the healing of infected wounds. Impressively, the wound dressing not only has excellent biocompatibility and long-term antibacterial properties but also performs well in accelerating wound healing. Therefore, this study provides a new strategy for the synthesis of intelligent adhesives with force rate response, which simplifies the triggering conditions by the force rate. Thus, SSA has great potential to be applied in wound management as an intelligent bioadhesive with on-demand adhesion performance.
Assuntos
Bandagens , Silicones , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Silicones/química , Adesivos/química , Adesivos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Camundongos , Adesivos Teciduais/química , Adesivos Teciduais/farmacologia , Humanos , Staphylococcus aureus/efeitos dos fármacosRESUMO
The accumulation of microplastics in agricultural soil brings unexpected adverse effects on crop growth and soil quality, which is threatening the sustainability of agriculture. Biochar is an emerging soil amendment material of interest as it can remediate soil pollutants. However, the mechanisms underlying biochar alleviated the toxic effects of microplastics in crops and soil were largely unknown. Using a common economic crop, peanut as targeted species, the present study evaluated the plant physiologica and molecular response and rhizosphere microbiome when facing microplastic contamination and biochar amendment. Transcriptome and microbiome analyses were conducted on peanut root and rhizosphere soil treated with CK (no microplastic and no biochar addition), MP (1.5% polystyrene microplastic addition) and MB (1.5% polystyrene microplastic+2% peanut shell biochar addition). The results indicated that microplastics had inhibitory effects on plant root development and rhizosphere bacterial diversity and function. However, biochar application could significantly promote the expressions of key genes associated with antioxidant activities, lignin synthesis, nitrogen transport and energy metabolism to alleviate the reactive oxygen species stress, root structure damage, nutrient transport limitation, and energy metabolism inhibition induced by microplastic contamination on the root. In addition, the peanut rhizosphere microbiome results showed that biochar application could restore the diversity and richness of microbial communities inhibited by microplastic contamination and promote nutrient availability of rhizosphere soil by regulating the abundance of nitrogen cycling-related and organic matter decomposition-related microbial communities. Consequently, the application of biochar could enhance root development by promoting oxidative stress resistance, nitrogen transport and energy metabolism and benefit the rhizosphere microecological environment for root development, thereby improved the plant-soil system health of microplastic-contaminated agroecosystem.
Assuntos
Microplásticos , Solo , Solo/química , Microplásticos/toxicidade , Plásticos , Rizosfera , Poliestirenos , Carvão Vegetal/farmacologia , Arachis , Nitrogênio/análise , Microbiologia do SoloRESUMO
Cerebrospinal fluid (CSF) rhinorrhea is one of the most common complications after trans-sphenoidal surgery. At present, transcranial or endoscopic surgery for CSF leakage requires general anesthesia to remove autologous fat or fascia to repair the leak, which is traumatic and costly. The authors present a case of a 25-year-old male patient with pituitary adenoma who experienced CSF rhinorrhea 10 days after undergoing endoscopic resection of the tumor. The authors innovatively sequential filled the leak with a gelatin sponge soaked in povidone-iodine solution and iodinated gauze under outpatient nasal endoscopy. The follow-up of 6 months showed no recurrence of CSF leakage. CSF leakage is the most common complication of trans-sphenoidal surgery. The authors suggest that for small cerebrospinal fluid leaks in the early stage after trans-sphenoidal surgery, the leakage should be first filled with gelatin sponge and iodoform gauze sequentially under outpatient nasal endoscopy, which may achieve a complete cure.
Assuntos
Rinorreia de Líquido Cefalorraquidiano , Endoscopia , Neoplasias Hipofisárias , Humanos , Masculino , Rinorreia de Líquido Cefalorraquidiano/cirurgia , Adulto , Neoplasias Hipofisárias/cirurgia , Endoscopia/métodos , Adenoma/cirurgia , Povidona-Iodo/uso terapêutico , Complicações Pós-Operatórias , Esponja de Gelatina Absorvível/uso terapêuticoRESUMO
BACKGROUND: The accumulation of microplastics in agricultural soil poses a threat to the sustainability of agriculture, impacting crop growth and soil health. Due to the geocarpy feature of peanut, geocarposphere soil environment is critical to pod development and its nutritional quality. While the effects of microplastics in the rhizosphere have been studied, their impact on peanut pod in the geocarposphere remains unknown. Biochar has emerged as a potential soil agent with the ability to remediate soil contamination. However, the mechanisms of biochar in mitigating the toxic effects of microplastics-contaminated geocarposphere soil on peanut pod development remain largely unexplored. RESULTS: We evaluated the peanut pod performance and microbiome when facing microplastics contamination and biochar amendment in geocarposphere soil. The results showed that microplastics present in geocarposphere soil could directly enter the peanut pod, cause pod developmental disorder and exert adverse effects on nutritional quality. Aberrant expression of key genes associated with amino acid metabolism, lipid synthesis, and auxin and ethylene signaling pathways were the underlying molecular mechanisms of microplastics-induced peanut pod developmental inhibition. However, these expression abnormalities could be reversed by biochar application. In addition, peanut geocarposphere microbiome results showed that biochar application could restore the diversity of microbial communities inhibited by microplastics contamination and promote the relative abundance of bacteria correlated with pathogen resistance and nitrogen cycle of geocarposphere soil, further promoting peanut pod development. CONCLUSION: This study demonstrated that biochar application is an effective strategy to mitigate the toxic effects of microplastics-contaminated geocarposphere soil on pod development and nutritional quality. © 2023 Society of Chemical Industry.
Assuntos
Arachis , Solo , Arachis/química , Solo/química , Microplásticos/metabolismo , Plásticos , Carvão Vegetal/metabolismoRESUMO
Reconstruction of large craniofacial defect after plexiform neurofibroma excision poses a continuous challenge for plastic surgeons, on account of characteristics of plexiform neurofibroma and patients' aesthetic requirements. Skin graft or free flap is hard to obtain satisfactory results or may pose technical challenges. In an attempt to provide the coverage with 'like tissue', we chose local tissue expansion technique. The expansion period was about an average of 3.4 months. We performed 19 expanded flaps located in the head, face, neck, forearm and superclavical regions to reconstruct the craniofacial defect and achieved satisfactory results. Preoperative endovascular embolism in some cases and several intraoperative hemostatic methods for all cases were undertaken to control the perioperative bleeding. For patients who request aesthetic results and are allowed two-staged operations, our method is viable.
Assuntos
Retalhos de Tecido Biológico , Neurofibroma Plexiforme , Procedimentos de Cirurgia Plástica , Humanos , Neurofibroma Plexiforme/cirurgia , Estética Dentária , Transplante de Pele/métodosRESUMO
BACKGROUND: E-cigarettes are commonly used in attempts to stop smoking, but evidence is limited regarding their effectiveness as compared with that of nicotine products approved as smoking-cessation treatments. METHODS: We randomly assigned adults attending U.K. National Health Service stop-smoking services to either nicotine-replacement products of their choice, including product combinations, provided for up to 3 months, or an e-cigarette starter pack (a second-generation refillable e-cigarette with one bottle of nicotine e-liquid [18 mg per milliliter]), with a recommendation to purchase further e-liquids of the flavor and strength of their choice. Treatment included weekly behavioral support for at least 4 weeks. The primary outcome was sustained abstinence for 1 year, which was validated biochemically at the final visit. Participants who were lost to follow-up or did not provide biochemical validation were considered to not be abstinent. Secondary outcomes included participant-reported treatment usage and respiratory symptoms. RESULTS: A total of 886 participants underwent randomization. The 1-year abstinence rate was 18.0% in the e-cigarette group, as compared with 9.9% in the nicotine-replacement group (relative risk, 1.83; 95% confidence interval [CI], 1.30 to 2.58; P<0.001). Among participants with 1-year abstinence, those in the e-cigarette group were more likely than those in the nicotine-replacement group to use their assigned product at 52 weeks (80% [63 of 79 participants] vs. 9% [4 of 44 participants]). Overall, throat or mouth irritation was reported more frequently in the e-cigarette group (65.3%, vs. 51.2% in the nicotine-replacement group) and nausea more frequently in the nicotine-replacement group (37.9%, vs. 31.3% in the e-cigarette group). The e-cigarette group reported greater declines in the incidence of cough and phlegm production from baseline to 52 weeks than did the nicotine-replacement group (relative risk for cough, 0.8; 95% CI, 0.6 to 0.9; relative risk for phlegm, 0.7; 95% CI, 0.6 to 0.9). There were no significant between-group differences in the incidence of wheezing or shortness of breath. CONCLUSIONS: E-cigarettes were more effective for smoking cessation than nicotine-replacement therapy, when both products were accompanied by behavioral support. (Funded by the National Institute for Health Research and Cancer Research UK; Current Controlled Trials number, ISRCTN60477608 .).
Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Abandono do Hábito de Fumar/métodos , Dispositivos para o Abandono do Uso de Tabaco , Tabagismo/terapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/administração & dosagem , Dispositivos para o Abandono do Uso de Tabaco/efeitos adversos , Resultado do Tratamento , Vaping/efeitos adversosRESUMO
Polymer-grafted hairy nanoparticles (HNPs) that combine the unique properties of inorganic nanoparticles (NPs) and polymers are attractive building blocks for the layer-by-layer assembly of functional hybrid materials, but the adsorption behaviors of HNPs on substrates remain unclear. This article describes a systematic study on the adsorption behaviors of charged polymer-grafted HNPs on oppositely charged substrates in different solvent media via a combination of experiments and simulations. It is shown in simulations that the adsorption process of HNPs is associated with the release of counterions around charged polymers on HNPs, thus resulting in a higher energy barrier of NP adsorption than bare NPs without charged polymer tethers. This energy barrier decreases with decreasing the dielectricity of solvents or ionization degree of grafted polymers or increasing ionic strength of the solution. Furthermore, the theoretical prediction is confirmed in experiments by using a model system of poly(acrylic acid)-grafted silica NPs and poly(diallyldimethylammonium chloride)-modified wafers. The work provides guidance for the electrostatic assembly of HNPs into functional hybrid composites with applications in membranes, optical devices, and biomedicines.
Assuntos
Nanopartículas , Polímeros , Adsorção , Nanopartículas/química , Polímeros/química , Eletricidade Estática , Propriedades de SuperfícieRESUMO
Helical polymers present some interesting and distinctive properties, and one of the most distinguished applications of them is the chiral recognition and resolution of enantiomers. In this work, star-shaped hybrid helical poly (phenyl isocyanide) (PPI) with polyhedral oligomeric silsesquioxanes (POSS) as the core was designed and synthesized by "grafting to" strategy. The homoarm star-shaped hybrid POSS-(PPI)8 was first obtained by the click reaction between azide-modified POSS (POSS-(N3 )8 ) and alkynyl-modified PPI (PPI-Alkynyl). The hybrid POSS-(PPI)8 was with predominated left-handed helical conformation and exhibited excellent ability in the enantioselective crystallization of racemic compounds. In the meantime, heteroarm star-shaped hybrid (PEG)4 -POSS-(PPI)4 was prepared by the click reaction of POSS-(N3 )8 with PPI-Alkynyl and alkynyl-modified poly (ethylene glycol) (PEG-Alkynyl). The hybrid (PEG)4 -POSS-(PPI)4 was amphiphilic, and it could self-assemble to form spherical micelles in aqueous solutions.
Assuntos
Micelas , Polímeros , Cristalização , Estereoisomerismo , ÁguaRESUMO
PURPOSE: To present our experience with pre-expanded medial upper arm flap in facial and neck reconstruction. PATIENTS AND METHODS: This was a retrospective study operated between January 1st, 2001 and January 1st, 2021, at the Plastic Surgery Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College. Staged face and/or neck reconstruction was performed. RESULTS: Forty-one patients were treated in our institution and thirty-eight patients (forty-three flaps) were included in this cohort as. They ranged from 6 to 44 years old. There was no total flap loss in the cohort. Partial flap necrosis was observed in the earlier patients (4 cases). CONCLUSION: Pre-expanded medial upper arm flap is well matched to the facial and neck skin in color, texture, and thickness. Considering the excellent aesthetic outcomes, this flap is a good alternative for selected patients with soft tissue defects of the head and neck.
Assuntos
Braço , Procedimentos de Cirurgia Plástica , Adolescente , Adulto , Braço/cirurgia , Criança , Estética Dentária , Humanos , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Retalhos Cirúrgicos/cirurgia , Adulto JovemRESUMO
The synthesis of optically pure polymers is one of the most challenging tasks in polymer chemistry. Herein, Novozym 435 (Lipase B from Candida antarctica, immobilized on Lewatit VP OC 1600)-catalyzed polycondensation between d-/l-aspartic acid (Asp) diester and diols for the preparation of helical chiral polyesters was reported. Compared with d-Asp diesters, the fast-reacting l-Asp diesters easily reacted with diols to provide a series of chiral polyesters containing N-substitutional l-Asp repeating units. Besides amino acid configuration, N-substituent side chains and the chain length of diols were also investigated and optimized. It was found that bulky acyl N-substitutional groups like N-Boc and N-Cbz were more favorable for this polymerization than small ones probably due to competitively binding of these small acyl groups into the active site of Novozym 435. The highest molecular weight can reach up to 39.5 × 103 g/mol (Mw, D = 1.64). Moreover, the slow-reacting d-Asp diesters were also successfully polymerized by modifying the substrate structure to create a "nonchiral" condensation environment artificially. These enantiocomplementary chiral polyesters are thermally stable and have specific helical structures, which was confirmed by circular dichroism (CD) spectra, scanning electron microscope (SEM), and molecular calculation.
Assuntos
Ácido Aspártico , Poliésteres , Basidiomycota , Catálise , Lipase , PolimerizaçãoRESUMO
BACKGROUND: The treatment of long-standing facial paralysis has always been a challenge for plastic surgery. The purpose of this study was to demonstrate that the free functional gracilis transfer innervated by the cross-facial nerve graft (CFNG) is still an ideal option, even though there are many new surgical options available. METHODS: A retrospective survey was made on 12 patients who received free functional gracilis transfer innervated by the CFNG. A modified version of the House-Brackmann scale was used to evaluate the movement of the corners of mouth after surgery. Patients were also asked about their satisfaction with the operation. In addition, an objective test was performed to assess the postoperative angle improvement by measuring the angle formed between the horizontal line of both corners of the lips and the vertical midline. RESULTS: All grafts survived well. No severe complication occurred. Three patients received further surgical operations for aesthetic reasons. The movement of the corners of mouth was classified as excellent in 8 cases, good in three cases, and fair in one cases. The static angle and dynamic angle of postoperation improved and the range of dynamic angle improvement was larger than that of static angle. CONCLUSION: Free functional gracilis transfer innervated by the CFNG is an ideal technique for facial paralysis. It can effectively improve the facial dynamic of the affected side.
Assuntos
Paralisia Facial , Músculo Grácil , Transferência de Nervo , Procedimentos de Cirurgia Plástica , Estética Dentária , Nervo Facial/cirurgia , Paralisia Facial/cirurgia , Humanos , Estudos Retrospectivos , SorrisoRESUMO
The thick and hard fruit shell of Fagopyrum tataricum (F. tataricum) represents a processing bottleneck. At the same time, soil salinization is one of the main problems faced by modern agricultural production. Bioinformatic analysis indicated that the F. tataricum transcription factor FtNAC16 could regulate the hull cracking of F. tataricum, and the function of this transcription factor was verified by genetic transformation of Arabidopsis thaliana (A. thaliana). Phenotypic observations of the wild-type (WT), OE-FtNAC16, nst1/3 and nst1/3-FtNAC16 plant lines confirmed that FtNAC16 negatively regulated pod cracking by downregulating lignin synthesis. Under salt stress, several physiological indicators (POD, GSH, Pro and MDA) were measured, A. thaliana leaves were stained with NBT (Nitroblue Tetrazolium) and DAB (3,3'-diaminobenzidine), and all genes encoding enzymes in the lignin synthesis pathway were analyzed. These experiments confirmed that FtNAC16 increased plant sensitivity by reducing the lignin content or changing the proportions of the lignin monomer. The results of this study may help to elucidate the possible association between changes in lignin monomer synthesis and salt stress and may also contribute to fully understanding the effects of FtNAC16 on plant growth and development, particularly regarding fruit pod cracking and environmental adaptability. In future studies, it may be useful to obtain suitable cracking varieties and salt-tolerant crops through molecular breeding.
Assuntos
Arabidopsis/fisiologia , Fagopyrum/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Salinidade , Tolerância ao Sal/genética , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , Lignina/biossíntese , Fenótipo , Filogenia , Desenvolvimento Vegetal , Estresse FisiológicoRESUMO
Exosomes are vesicles with sizes ranging from 30 to 150 nm. The analysis and detection of blood exosomes offers an effective route for cancer diagnosis, prognosis assessment, and therapeutic evaluation of diseases. Due to the difference in separation procedure, collection method and the usage of anticoagulants, serum and plasma samples show diversity test results. In order to evaluate the isolation effect of exosomes in serum and plasma samples, two commonly used exosomal isolation methods, ultracentrifugation and polymer-based precipitation kit, were used, respectively. And the isolation effects were evaluated by comparing the composition and abundant of proteins from isolated exosomes based on MS-based proteomics analysis. The results showed that the plasma exosomes extracted by ultracentrifugation identified more exosome biomarkers, and the concentrations of these biomarkers were higher than others. And plasma exosomes could be a better sample for blood-based proteomics research of exosomes. It would be more useful for future targeted biomarker discovery.
Assuntos
Proteínas Sanguíneas/análise , Exossomos/química , Proteômica/métodos , Ultracentrifugação/métodos , Proteínas Sanguíneas/química , Precipitação Química , Humanos , Polímeros , Proteoma/análise , Proteoma/química , Espectrometria de Massas em TandemRESUMO
Herein we demonstrated a novel lipase-catalyzed synthesis of isotactic D-/L-poly(aspartate-octanediol) ester containing long chain alcohols backbone and discovered their stereocomplex feature with an increased Tm for the first time. Simple design of monomer structures not only overcomes the inherent selectivity limitation of enzyme used, but also achieves totally isotactic polyester products. By crystallizing the mixed enantiopure isotactic polyesters in different solvents, the formation of amorphous mixture, homocrystallites or stereocomplex crystallites were observed, respectively. This study is expected to open up a new way to prepare various stereocomplex polyesters containing a long-chain aliphatic alcohol backbone and a wide variety of functional groups.
Assuntos
Álcoois/química , Poliésteres/química , Polímeros/química , Catálise , Cristalização , Etanol/química , Lipase/química , Poliésteres/síntese química , Poliésteres/farmacologia , Polímeros/síntese química , Polímeros/farmacologia , Solventes/química , Solventes/farmacologiaRESUMO
PURPOSE: Neurotrophin receptor-interacting MAGE homologue (Nrage) plays an important role in bone development and the metabolism of normal skeletal structures. Our previous study showed that Nrage inhibited the odontogenic differentiation of mouse dental pulp cells. However, the potential roles and mechanism of Nrage in regulating odontogenic differentiation are unknown. The aim of this study was to investigate the molecular mechanism of Nrage in odontogenic differentiation of mouse odontoblast-like cells. MATERIALS AND METHODS: Endogenous expression of Nrage was stably downregulated by lentivirus-mediated shRNA. Mineralized nodules formation was detected by alizarin red S staining. Dmp-1, Dspp, and ALP mRNA and protein levels were detected by qRT-PCR and western blotting, respectively. In addition, ALPase activity was detected. Confocal microscopy and co-immunoprecipitation (co-IP) were used to analyze the interactions between NRAGE and NF-κB signaling molecules. An IKK inhibitor was also used in the study. RESULTS: NRAGE expression in odontoblasts was downregulated during mouse first maxillary molar development. Moreover, NRAGE expression was downregulated during odontogenic differentiation of odontoblast-like cells. NRAGE knockdown significantly upregulated DMP1 and DSP expression, increased ALPase activity, and promoted mineralized nodule formation. In addition, NRAGE knockdown increased the translocation of NF-κB1 to the nucleus and phosphorylation levels of p65. Co-IP results showed that NRAGE bound to IKKß. Most importantly, the promoting effect of Nrage knockdown on odontoblastic differentiation was reduced after treatment with an IKK inhibitor. CONCLUSIONS: Our data confirmed that NRAGE is an important regulator of odontogenic differentiation of odontoblasts by inhibiting the NF-κB signaling pathway through binding to IKKß. ABBREVIATIONS: Nrage: neurotrophin receptor-interacting MAGE homologue; DSP: dentin sialophospho protein; DMP-1: dentin matrix protein-1; BMP: bone morphogenetic protein; Wnt: wingless; NF-κB: nuclear factor of activated B cells; DAPI: 4',6-diamidino-2-phenylindole; KO: knockout; DPCs: dental pulp cells; AA: ascorbic acid; ß-Gly: ß-glycerophosphate; Dex: dexamethasone; co-IP: co-immunoprecipitation; IκB: inhibitor of NF-κB; IKK: IκB kinase.
Assuntos
Diferenciação Celular , Técnicas de Silenciamento de Genes , NF-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Odontoblastos/citologia , Odontoblastos/metabolismo , Odontogênese , Transdução de Sinais , Fosfatase Alcalina/metabolismo , Animais , Biomarcadores/metabolismo , Calcificação Fisiológica , Diferenciação Celular/genética , Linhagem Celular , Regulação para Baixo/genética , Proteínas da Matriz Extracelular/metabolismo , Quinase I-kappa B/metabolismo , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/genética , Odontogênese/genética , Ligação ProteicaRESUMO
BACKGROUND: Audiovisual distraction, a non-pharmacological intervention, has been used to manage dental anxiety in prior clinical trials. AIM: Synthesize the available evidences to evaluate the efficacy of audiovisual distraction techniques on the management of dental anxiety in children. DESIGN: Electronic databases (PubMed, Cochrane Central Register of Controlled Trials, and Embase) were searched. We included randomized controlled trials (RCTs), and methodological quality of included trials was assessed using the Cochrane Collaboration's criteria. Information on reported anxiety, pain, behaviors, vital signs (including blood pressure, oxygen saturation, and pulse rate), and children satisfaction was analyzed. RESULTS: Nine studies were included for a systematic review, and none of them had low risk of bias. Significant differences in anxiety were found. According to the study, a majority of results indicated a significant difference in pain and behavior between the audiovisual and control group. Three studies reported children in the audiovisual group preferred usage of an audiovisual device for future dental visits. No significant differences could be found regarding blood pressure. CONCLUSIONS: There is some low-quality evidence suggesting that the usage of audiovisual distraction during dental treatment may relieve children's dental anxiety.
Assuntos
Recursos Audiovisuais , Ansiedade ao Tratamento Odontológico/terapia , Adolescente , Criança , Pré-Escolar , Humanos , Distorção da Percepção , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
The objective was to investigate whether a graphene coating could improve the surface bioactivity of a cobalt-chromium-molybdenum-based alloy (CoCrMo). Graphene was produced by chemical vapor deposition and transferred to the surface of the CoCrMo alloy using an improved wet transfer approach. The morphology of the samples was observed, and the adhesion force and stabilization of graphene coating were analyzed by a nanoscratch test and ultrasonication test. In an in vitro study, the adhesion and proliferation of bone marrow mesenchymal stem cells (BMSCs) cultured on the samples were quantified via an Alamar Blue assay and cell counting kit-8 (CCK-8) assay. The results showed that it is feasible to apply graphene to modify the surface of a CoCrMo alloy, and the enhancement of the adhesion and proliferation of BMSCs was also shown in the present study. In conclusion, graphene exhibits considerable potential for enhancing the surface bioactivity of CoCrMo alloy.
Assuntos
Células da Medula Óssea/citologia , Materiais Revestidos Biocompatíveis/química , Grafite/química , Células-Tronco Mesenquimais/citologia , Vitálio/química , Células da Medula Óssea/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Grafite/farmacologia , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacosRESUMO
Amino acids are attractive monomers for the large-scale preparation of chiral polyamides. For enzymatic polymerization of amino acids using protease in aqueous environment as the catalysis system, one main restriction is oligomer formation, usually along with other displayed advantages. Herein we developed an efficient solvent-free lipase-catalyzed polymerization of diethyl D- or L-aspartate, providing chiral D- and L-polyaspartates with an average degree of polymerization (DPavg) up to 60 and having about 96% ß-linkages. Additionally, their distinct chemical and physical properties were characterized by circular dichroism (CD) spectra, X-ray powder diffraction (XRD), microscopic observation, and thermal analysis. Poly(ß-D-AspEt) and Poly(ß-L-AspEt) showed vertically mirrored negative and positive CD signals, high crystallinity, and entirely different microscopic morphology. They are thermal stable while having different decomposition (Td), melting (Tm), and cold crystallization temperatures (Tcc), respectively. Our results also showed that the complexation of enantiopure D- and L-polyaspartates was not stereocomplex but homocomplex.
Assuntos
Ácido Aspártico/química , Lipase/metabolismo , Nylons/síntese química , Peptídeo Hidrolases/metabolismo , Peptídeos/química , Peptídeos/síntese química , Catálise , Dicroísmo Circular/métodos , Lipase/química , Polimerização , Polímeros/síntese química , Polímeros/química , Solventes/química , Difração de Raios X/métodosRESUMO
Nanocrystalline cellulose (NCC) with high surface area and high ordered crystalline structure was prepared from microcrystalline cellulose (MCC) under the hydrolysis of sodium hypochlorite. NCC was further reacted with 3,5-dimethylphenyl isocyanate to obtain the nanocellulose derivative, and then coated successfully on the surface of silica gel to a prepared NCC-coated chiral stationary phase (CSP) as a new kind of chiral separation material. Similarly, MCC derivative-coated CSP was also prepared as contrast. The chiral separation performance of NCC-based CSP was evaluated and compared with MCC-based CSP by high-performance liquid chromatography. Moreover, the effects of the alcohol modifiers, mobile phase additives, and flow rates on chiral separations were investigated in detail. The results showed that 10 chiral compounds were separated on NCC-based CSP with better peak shape and higher column efficiency than MCC-based CSP, which confirmed that NCC-based CSP was a promising packing material for the resolution of chiral compounds.Chirality 28:376-381, 2016. © 2016 Wiley Periodicals, Inc.