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1.
Proc Natl Acad Sci U S A ; 119(49): e2215028119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36442122

RESUMO

The climbing microrobots have attracted growing attention due to their promising applications in exploration and monitoring of complex, unstructured environments. Soft climbing microrobots based on muscle-like actuators could offer excellent flexibility, adaptability, and mechanical robustness. Despite the remarkable progress in this area, the development of soft microrobots capable of climbing on flat/curved surfaces and transitioning between two different surfaces remains elusive, especially in open spaces. In this study, we address these challenges by developing voltage-driven soft small-scale actuators with customized 3D configurations and active stiffness adjusting. Combination of programmed strain distributions in liquid crystal elastomers (LCEs) and buckling-driven 3D assembly, guided by mechanics modeling, allows for voltage-driven, complex 3D-to-3D shape morphing (bending angle > 200°) at millimeter scales (from 1 to 10 mm), which is unachievable previously. These soft actuators enable development of morphable electroadhesive footpads that can conform to different curved surfaces and stiffness-variable smart joints that allow different locomotion gaits in a single microrobot. By integrating such morphable footpads and smart joints with a deformable body, we report a multigait, soft microrobot (length from 6 to 90 mm, and mass from 0.2 to 3 g) capable of climbing on surfaces with diverse shapes (e.g., flat plane, cylinder, wavy surface, wedge-shaped groove, and sphere) and transitioning between two distinct surfaces. We demonstrate that the microrobot could navigate from one surface to another, recording two corresponding ceilings when carrying an integrated microcamera. The developed soft microrobot can also flip over a barrier, survive extreme compression, and climb bamboo and leaf.


Assuntos
Elastômeros , Cristais Líquidos , Membrana Celular , Extremidades , Marcha
2.
Environ Res ; 223: 115409, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36746203

RESUMO

An important way to promote the environmental industry's goal of carbon reduction is to promote the recycling of resources. Membrane separation technology has unique advantages in resource recovery and advanced treatment of industrial wastewater. However, the great promise of traditional organic membrane is hampered by challenges associated with organic solvent tolerance, lack of oxidation resistance, and serious membrane fouling control. Moreover, the high concentrations of organic matter and inorganic salts in the membrane filtration concentrate also hinder the wider application of the membrane separation technology. The emerging cost-effective graphene oxide (GO)-based membrane with excellent resistance to organic solvents and oxidants, more hydrophilicity, lower membrane fouling, better separation performance has been expected to contribute more in industrial wastewater treatment. Herein, we provide comprehensive insights into the preparation and characteristic of GO membranes, as well as current research status and problems related to its future application in industrial wastewater treatment. Finally, concluding remarks and future perspectives have been deduced and recommended for the GO membrane separation technology application for industrial wastewater treatment, which leads to realizing sustainable wastewater recycling and a nearly "zero discharge" water treatment process.


Assuntos
Grafite , Purificação da Água , Águas Residuárias , Membranas Artificiais
3.
Cytokine ; 137: 155352, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33128918

RESUMO

OBJECTIVE: Temporomandibular joint osteoarthritis (TMJOA) is a common degenerative disease in jaw joint, accompanied by articular cartilage destruction. Differentiation of stem cells to cartilage has important therapeutic implications in TMJ cartilage repair. Previous studies revealed that lncRNA XIST participated in various biological processes. However, the effect of XIST on chondrogenic differentiation of synovium-derived mesenchymal stem cells (SMSCs) remains unclear. Our study aimed to investigate the function of XIST in chondrogenic differentiation of human SMSCs from TMJ. METHODS: Alcian blue staining was performed to determine proteoglycan in SMSCs. qPCR, western blotting and immunofluorescence assays were allowed to assess sex determining region Y-box 9 (SOX9), Collagen type II alpha 1 chain (COL2A1) and Aggrecan (ACAN) expression. The direct interaction between miR-27b-3p and XIST or ADAMTS-5 was confirmed by dual luciferase reporter assay or RNA immunoprecipitation (RIP) assay. RESULTS: XIST was remarkably down-regulated in chondrogenic differentiation of SMSCs. Functional analysis demonstrated that XIST silencing promoted chondrogenic differentiation of SMSCs. Dual luciferase reporter and RIP assays identified that XIST acted as a sponge for miR-27b-3p. Moreover, XIST regulated ADAMTS-5 expression by directly binding miR-27b-3p. More importantly, miR-27b-3p/ADAMTS-5 rescued the effects of XIST on chondrogenic differentiation of SMSCs. CONCLUSION: The results suggest that XIST modulates SMSCs chondrogenic differentiation via the miR-27b-3p/ADAMTS-5 axis, which provides new targets for TMJOA treatment.


Assuntos
Proteína ADAMTS5/genética , Diferenciação Celular/genética , Condrogênese/genética , Células-Tronco Mesenquimais/metabolismo , RNA Longo não Codificante/genética , Articulação Temporomandibular/metabolismo , Proteína ADAMTS5/metabolismo , Sequência de Bases , Western Blotting , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Regulação da Expressão Gênica , Humanos , MicroRNAs/genética , Microscopia de Fluorescência , Osteoartrite/genética , Osteoartrite/metabolismo , Osteoartrite/terapia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Membrana Sinovial/citologia
4.
BMC Infect Dis ; 20(1): 271, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32264839

RESUMO

BACKGROUND: Hand, foot, and mouth disease (HFMD) is a common infectious disease occurring in children under 5 years of age worldwide, and Enterovirus A71 (EV-A71) and Coxsackievirus A16 (CVA-16) are identified as the predominant pathogens. In recent years, Coxsackievirus A6 (CVA-6) and Coxsackievirus A10 (CVA-10) have played more and more important role in a series of HFMD outbreaks. This study aimed to understand the epidemic characteristics associated with HFMD outbreak in Guangzhou, 2018. METHODS: The clinical and laboratory data of 1220 enterovirus-associated HFMD patients in 2018 were analysed in this study. Molecular diagnostic methods were performed to identify its serotypes. Phylogenetic analyses were depicted based on the complete VP1 gene. RESULTS: There were 21 enterovirus serotypes detected in Guangzhou in 2018. Three serotypes of enterovirus, CVA-6 (364/1220, 29.8%), CVA-10 (305/1220, 25.0%), and CVA-16 (397/1220, 32.5%), were identified as the causative pathogens and accounted for 87.3% among all 1220 HFMD patients. In different seasons, CVA-6 was the predominant pathogen of HFMD during autumn, and CVA-10 as well as CVA-16 were more prevalent in summer. Patients infected by CVA-6, CVA-10 or CVA-16 showed similar clinical features and laboratory characteristics, and the ratios of severe HFMD were 5.8, 5.9, and 1.5% in the three serotypes. Phylogenetic analyses of VP1 sequences showed that the CVA-6, CVA-10, and CVA-16 sequences belonged to the sub-genogroup E2, genogroup E, and genogroup B1, respectively. CONCLUSIONS: CVA-6, CVA-10, and CVA-16 were the predominant and co-circulated serotypes in Guangzhou China, 2018, which should be the new target for prevention and control of HFMD. Our findings provide useful information for diagnosis, treatment, and prevention of HFMD.


Assuntos
Enterovirus Humano A/classificação , Enterovirus Humano A/genética , Epidemias , Doença de Mão, Pé e Boca/epidemiologia , Sequência de Bases/genética , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , China/epidemiologia , Feminino , Genótipo , Doença de Mão, Pé e Boca/virologia , Humanos , Lactente , Masculino , Filogenia , Prevalência , Estações do Ano , Sorogrupo
5.
Environ Sci Technol ; 53(3): 1501-1508, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30592608

RESUMO

Graphene oxide (GO) membranes have the potential to be next-generation membranes. However, the GO layer easily swells in water and risks shedding during the long-term filtration. Organic GO interlayer organic cross-linking agent was not resistant to oxidation, which limits the application scope of GO membrane. In this study, an inorganic cross-linked GO membrane was prepared via the reaction of sodium tetraborate and GO hydroxyl groups, and a -B-O-C- cross-linking bond was detected by X-ray photoelectron spectroscopy (XPS). Additionally, a new atomic force microscope scratch method to evaluate the cross-linking force of a nanoscale GO layer was proposed. It showed that the critical destructive load of the inorganic cross-linked GO membrane increased from 8 to 80 nN, which was a 10-fold increase from that of the nonlinked sample. During the NaOH/sodium dodecyl sulfate (SDS) destructive wash tests, morphology, flux and retention rate of inorganic cross-linked GO remained stable while the comparative membranes showed significant destruction. At the same time, based on the better oxidation resistance, organic membrane fouling was effectively controlled by the introduction of trace ·OH radicals. This study provides a new perspective for GO membrane preparation, interlayer cross-linking force testing and membrane fouling control.


Assuntos
Grafite , Boratos , Filtração , Membranas Artificiais , Óxidos
6.
Molecules ; 24(7)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30987040

RESUMO

A phytochemical investigation of the roots of Swietenia macrophylla led to the isolation of seven polyacetylenes, including five new compounds (1-5) and two known ones (6-7). Their structures were elucidated by extensive spectroscopic analysis and detailed comparison with reported data. All the isolates were tested for their cytotoxicity against the human hepatocellular carcinoma cell line BEL-7402, human myeloid leukemia cell line K562, and human gastric carcinoma cell line SGC-7901. Compounds 1 and 6 showed moderate cytotoxicity against the above three human cancer cell lines with IC50 values ranging from 14.3 to 45.4 µM. Compound 4 displayed cytotoxicity against the K562 and SGC-7901 cancer cell lines with IC50 values of 26.2 ± 0.4 and 21.9 ± 0.3 µM, respectively.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Meliaceae/química , Raízes de Plantas/química , Polímero Poliacetilênico/farmacologia , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Células K562 , Polímero Poliacetilênico/química
7.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(3): 379-382, 2019 Jun 30.
Artigo em Zh | MEDLINE | ID: mdl-31282333

RESUMO

Objective To compare the impacts of different nostril on nasotracheal intubation with video laryngoscopy.Methods Totally 120 ASA grade I maxillofacial surgery patients were equally randomized into two groups:group A(left nostril)and group B(right nostril).After rapid induction of anesthesia,the nasal intubation was completed by Tosight video laryngoscope,and the success rate of the first attempt of the tube passing through the nasal cavity was recorded and compared between these two groups.In addition,time of tube through nasal cavity,time of glottis exposure,total intubation time,intubation success rate,and nasal bleeding were recorded.Results The success rate of the first attempt of tube passing through the nasal cavity was not significantly different between groups A and B(84.7% vs. 81.7%;χ 2=0.202,P=0.653).The time of tube passing through nasal cavity [(7.3±4.6)s vs.(7.5±4.1)s;t=-0.223,P=0.824] and the time of glottic exposure [(6.6±1.4)s vs.(6.7±1.4)s;t=-0.348,P=0.728] had no significant differences between two groups.The success rates of first intubation attempt were 100% in both groups.The total intubation time was(35.1±9.2)s in group A and(34.0±7.8)s in group B(t=0.663,P=0.509).Intubation-related epistaxis was found in 16 cases(27.1%)in group A and in 17 cases(28.3%)in group B(χ 2 =0.022,P=0.882).Conclusion Different nasal approaches have no effect on nasal intubation.


Assuntos
Intubação Intratraqueal/métodos , Laringoscopia , Cavidade Nasal , Glote , Humanos , Laringoscópios , Procedimentos Cirúrgicos Bucais
8.
Pharm Res ; 36(1): 20, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30511187

RESUMO

PURPOSE: The pH-responsive copolymer micelles are widely used as carriers in drug delivery system, but there are few micro-level mechanistically explorations on the pH-triggered drug release. Here we elucidate the relationship between drug release behavior of four/six-arms star copolymer micelles and the copolymer structures. METHOD: The net cumulative drug release percentage (En) was taken as the dependent variables, block unit autocorrelation descriptors as independent variables. The quantitative structure-property relationship models of drug release from block copolymers were developed at pH 7.4 and 5.0 of two periods (stage I: 0~12 h, stage II: 12~96 h). RESULTS: The models built are of good fitting ability, internal predictive ability, stability and statistically significance. Drug diffusion is mainly influenced by the intra-block force, and micellar erosion by inter-block force. At pH 5.0, lowest unoccupied molecular orbital energy of copolymer unit is the main factor influencing the En. Stage I of drug release is affected by hydrophobic property and stage II by regional polar of copolymer molecules. CONCLUSION: The models present good performance, factors affecting drug release behavior at different pH conditions can offer guidance for the design of copolymer structures to control the drug release behavior of micelles in a targeted and quantitatively way.


Assuntos
Micelas , Polímeros/química , Portadores de Fármacos , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Relação Quantitativa Estrutura-Atividade
9.
BMC Psychiatry ; 18(1): 345, 2018 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-30342524

RESUMO

BACKGROUND: Tooth loss is suggested to be associated with an increased risk of dementia in many studies. But the relationship between tooth loss and dementia is not yet fully understood. This systematic review and meta-analysis aimed to determine the relative effect of tooth loss on dementia risk. METHODS: An electronic search of PubMed, Scopus, Embase, and Web of Knowledge was conducted in March 2018 to identify relevant observational studies with the English language restriction. Studies were included if they assessed the relationship between tooth loss and risk of dementia. Study quality was detected by the modified Downs and Black scale. Odds risks (ORs) were pooled using a random-effects model in the crude model. RESULTS: The literature search initially yielded 1574 articles, and 21 observational studies published between 1994 and 2017 were finally included for the analyses. The crude results with random-effects model showed that patients with multiple tooth loss had higher incidence of dementia (OR 2.62, 95% CI 1.90-3.61, P < 0.001, I2 = 90.40%). The association remained noted when only adjusted results were pooled from 18 studies (OR 1.55, 95% CI 1.41-1.70, P = 0.13, I2 = 28.00%). Meta-regression analysis showed that study design explained about 16.52% of heterogeneity in the crude model. The overall quality rating scores of studies ranged from 11 to 16. CONCLUSIONS: Findings from this review evidenced that tooth loss is positively associated with an increased risk of dementia in adults. Future well-designed longitudinal researches examining the direct and indirect relationship between tooth loss and dementia risk are encouraged.


Assuntos
Demência/etiologia , Perda de Dente/psicologia , Adulto , Idoso , Demência/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Razão de Chances , Análise de Regressão , Fatores de Risco
10.
Int J Med Sci ; 15(2): 129-141, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29333097

RESUMO

Purpose: To establish small-sized superparamagnetic polymeric micelles for magnetic resonance and fluorescent dual-modal imaging, we investigated the feasibility of MR imaging (MRI) and macrophage-targeted in vitro. Methods: A new class of superparamagnetic iron oxide nanoparticles (SPIONs) and Nile red-co-loaded mPEG-Lys3-CA4-NR/SPION polymeric micelles was synthesized to label Raw264.7 cells. The physical characteristics of the polymeric micelles were assessed, the T2 relaxation rate was calculated, and the effect of labeling on the cell viability and cytotoxicity was also determined in vitro. In addition, further evaluation of the application potential of the micelles was conducted via in vitro MRI. Results: The diameter of the mPEG-Lys3-CA4-NR/SPION polymeric micelles was 33.8 ± 5.8 nm on average. Compared with the hydrophilic SPIO, mPEG-Lys3-CA4-NR/SPION micelles increased transversely (r2), leading to a notably high r2 from 1.908 µg/mL-1S-1 up to 5.032 µg/mL-1S-1, making the mPEG-Lys3-CA4-NR/SPION micelles a highly sensitive MRI T2 contrast agent, as further demonstrated by in vitro MRI. The results of Confocal Laser Scanning Microscopy (CLSM) and Prussian blue staining of Raw264.7 after incubation with micelle-containing medium indicated that the cellular uptake efficiency is high. Conclusion: We successfully synthesized dual-modal MR and fluorescence imaging mPEG-Lys3-CA4-NR/SPION polymeric micelles with an ultra-small size and high MRI sensitivity, which were effectively and quickly uptaken into Raw 264.7 cells. mPEG-Lys3-CA4-NR/SPION polymeric micelles might become a new MR lymphography contrast agent, with high effectiveness and high MRI sensitivity.


Assuntos
Meios de Contraste/química , Macrófagos/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Micelas , Polímeros/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/farmacologia , Compostos Férricos/química , Corantes Fluorescentes/química , Espectroscopia de Ressonância Magnética , Nanopartículas de Magnetita/química , Camundongos , Oxazinas/química , Tamanho da Partícula , Polímeros/síntese química , Células RAW 264.7
11.
Biomed Environ Sci ; 29(8): 594-598, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27660224

RESUMO

We used Smo siRNA to inhibit hedgehog signaling pathway in embryonic day (E) 13 palatal shelves in organ culture. SiRNA 4 was chosen as the most efficient from four synthesized Smo siRNAs. Palatal shelf fusion rate of 4 µg/mL cyclopamine group was the lowest and significantly lower than that of blank control group (P<0.05), and that of siRNA 4 group was also lower than that of blank control group (P=0.183). At 48 h after transfection, Smo protein level of siRNA 4 group was 64.8% lower than that of blank control group (P<0.05), and Gli1 protein level of 4 µg/mL cyclopamine group was 68.9% lower than that of blank control group (P<0.05). Hedgehog signaling pathway inhibition decreased palatal fusion in organ culture, probably owing to downregulation of Smo and Gli1 proteins.


Assuntos
Proteínas Hedgehog/metabolismo , Palato/embriologia , RNA Interferente Pequeno/genética , Transdução de Sinais , Animais , Proteínas Hedgehog/genética , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Palato/metabolismo , RNA Interferente Pequeno/metabolismo , Proteína Gli2 com Dedos de Zinco , Proteína Gli3 com Dedos de Zinco
12.
Beijing Da Xue Xue Bao Yi Xue Ban ; 48(1): 10-5, 2016 Feb 18.
Artigo em Zh | MEDLINE | ID: mdl-26885902

RESUMO

OBJECTIVE: To investigate the potential association between FADS1 rs174537 polymorphism and serum proteins in patients with aggressive periodontitis, which may provide benefits for diagnosis and treatment of aggressive periodontitis. METHODS: A total of 353 patients with aggressive periodontitis (group AgP) and 125 matched controls (group HP) were recruited in the study. Genotyping of FADS1 rs174537 and serum biochemical indexes were tested at the study's start. The relationships between the levels of TP, GLB, ALB, A/G and genotyping were analyzed. RESULTS: (1) The detection rate of allele G in group AgP was higher than that in group HP(68.1% vs. 61.2%, P=0.046,OR=1.35,95% CI 1.00-1.83); the detection rate of genotype GG in group AgP was higher than in group HP(45.5% vs. 34.4%,P=0.029, OR=1.60, 95% CI 1.05-2.44). (2) In group AgP, the patients with GG genotype exhibited significantly lower TP, GLB than the patients with GT+TT genotype [(77.08 ± 7.88) g/L vs. (79.00 ± 4.66) g/L, P=0.007; (28.17 ± 7.63) g/L vs.(29.88 ± 3.49) g/L,P=0.007) and the higher A/G(1.72 ± 0.22 vs.1.67 ± 0.22, P=0.040), but there was no significant difference in ALB between the patients with GG genotype and the patients with GT+TT genotype. In group HP, there were no significant differences in TP, GLB, A/G and ALB between individuals with genotype GT+TT and with genotype GG. (3)Compared with individuals with genotype GT+TT in group HP, the AgP patients with genotype GT+TT exhibited significantly higher TP, GLB [(79.00 ± 4.66) g/L vs. (75.20 ± 4.53) g/L, P<0.01; (29.88 ± 3.49) g/L vs.(26.55 ± 2.94) g/L, P<0.01) and the lower A/G(1.67 ± 0.22 vs. 1.88 ± 0.30, P<0.01), but there was no significant difference in ALB. There were no significant differences in TP, GLB, A/G and ALB the between the AgP patients with genotype GG and the healthy subjects with the same genotype either. CONCLUSION: FADS1 rs174537 polymorphism is associated with aggressive periodontitis. The patients with genotype GG in group AgP had relatively lower TP,GLB and higher A/G. Genotype GG might be a risk indicator for aggressive periodontitis by reducing host defense capability and contributing to inflammatory response in the occurrence and development of aggressive periodontitis.


Assuntos
Periodontite Agressiva/genética , Proteínas Sanguíneas/metabolismo , Ácidos Graxos Dessaturases/genética , Alelos , Estudos de Casos e Controles , Dessaturase de Ácido Graxo Delta-5 , Genótipo , Humanos , Polimorfismo Genético , Fatores de Risco
13.
Anal Chem ; 87(21): 11105-12, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26461918

RESUMO

Human enterovirus 71 (EV71) is one of the pathogens that causes hand, foot, and mouth disease (HFMD), which generally leads to neurological diseases and fatal complications among children. Since the early clinical symptoms from EV71 infection are very similar to those from Coxsackievirus B3 (CVB3) infection, a robust and sensitive detection method that can be used to distinguish EV71 and CVB3 is urgently needed for prompting medical treatment of related diseases. Herein, based on immunomagnetic nanobeads and fluorescent semiconductor CdSe quantum dots (QDs), a method for simultaneous point-of-care detection of EV71 and CVB3 is proposed. The synchronous detection of EV71 and CVB3 virions was achieved within 45 min with high specificity and repeatability. The limits of detection are 858 copies/500 µL for EV71 and 809 copies/500 µL for CVB3.This proposed method was further validated with 20 human throat swab samples obtained from EV71 or CVB3 positive cases, with results 93.3% consistent with those by the real-time PCR method, demonstrating the potential of this method for clinical quantification of EV71 and CVB3. The method may also facilitate the prevention and treatment of the diseases.


Assuntos
Enterovirus Humano A/isolamento & purificação , Enterovirus Humano B/isolamento & purificação , Sistemas Automatizados de Assistência Junto ao Leito , Pontos Quânticos , Espectrometria de Fluorescência
14.
Environ Sci Technol ; 49(4): 2341-9, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25594559

RESUMO

Using a CH4-based membrane biofilm reactor (MBfR), we studied perchlorate (ClO4(-)) reduction by a biofilm performing anaerobic methane oxidation coupled to denitrification (ANMO-D). We focused on the effects of nitrate (NO3(-)) and nitrite (NO2(-)) surface loadings on ClO4(-) reduction and on the biofilm community's mechanism for ClO4(-) reduction. The ANMO-D biofilm reduced up to 5 mg/L of ClO4(-) to a nondetectable level using CH4 as the only electron donor and carbon source when CH4 delivery was not limiting; NO3(-) was completely reduced as well when its surface loading was ≤ 0.32 g N/m(2)-d. When CH4 delivery was limiting, NO3(-) inhibited ClO4(-) reduction by competing for the scarce electron donor. NO2(-) inhibited ClO4(-) reduction when its surface loading was ≥ 0.10 g N/m(2)-d, probably because of cellular toxicity. Although Archaea were present through all stages, Bacteria dominated the ClO4(-)-reducing ANMO-D biofilm, and gene copies of the particulate methane mono-oxygenase (pMMO) correlated to the increase of respiratory gene copies. These pieces of evidence support that ClO4(-) reduction by the MBfR biofilm involved chlorite (ClO2(-)) dismutation to generate the O2 needed as a cosubstrate for the mono-oxygenation of CH4.


Assuntos
Reatores Biológicos , Metano/química , Consórcios Microbianos/fisiologia , Percloratos/química , Anaerobiose , Archaea/genética , Archaea/metabolismo , Bactérias/genética , Bactérias/metabolismo , Biofilmes , Reatores Biológicos/microbiologia , Carbono/química , Desnitrificação , Elétrons , Regulação da Expressão Gênica , Membranas Artificiais , Metano/metabolismo , Nitratos/metabolismo , Oxirredução , Percloratos/metabolismo , Permeabilidade , RNA Ribossômico 16S
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 47(1): 27-31, 2015 Feb 18.
Artigo em Zh | MEDLINE | ID: mdl-25686324

RESUMO

OBJECTIVE: To evaluate the feasibility of full-mouth debridement (subgingival scaling and root planning, SRP) by 2 times within 1 week and compare the clinical effects of different sequences of debridement-antibiotic usage in patients with severe chronic periodontitis (CP). METHODS: A double-blinded, placebo-controlled, randomized clinical trial was conducted in 30 severe CP patients (14 males and 16 females, 40.5 ± 8.4 years old on average from 35 to 60) receiving 3 different sequences of debridement-antibiotictherapy: Group A, antibiotic usage (metronidazole, MTZ, 0.2 g, tid, 7 d; amoxicillin, AMX 0.5 g, tid, 7 d) was started together with SRP (completed by 2 times in 7 d); Group B, antibiotic usage (MTZ 0.2 g, tid, 7 d; AMX 0.5 g, tid, 7 d) was started 1 d after SRP(completed by 2 times in 7 d); Group C, SRP alone[probing depth (PD), bleeding index (BI) and tooth mobility] was examined. The average full-mouth probing depth, the average full-mouth proximal probing depth (pPD), the percentage of sites with PD>5 mm (PD>5 mm%), the percentage of sites with proximal PD>5 mm (pPD>5 mm%), the average bleeding index (BI) and the percentage of sites with bleeding on probing (BOP%) were calculated. Clinical examinations were performed at baseline and 2 months post therapy. RESULTS: (1) Compared with baseline conditions, all the subjects showed clinical improvements in all the parameters evaluated 2 months post therapy, P<0.05. (2) Significant difference were observed in the average PD changes between Group A [(2.15 ± 0.42) mm], Group B [(1.76 ± 0.29) mm] and Group C [(1.57 ± 0.33) mm], P<0.05. No significant difference was observed in the average PD changes between Group B and Group C, P=0.354. Significant differences were observed in the average pPD changes between Group A [(2.45 ± 0.43)mm] and Group C[(1.90 ± 0.48) mm], P<0.05. No significant difference was observed in BI and BOP% changes between Group A,Group B and Group C. CONCLUSION: For patients with severe chronic periodontitis, it is safe and feasible to receive full-mouth SRP by 2 times within 1 week. The short-term (2 months) advantages in PD changes are observed in patients receiving SRP and antibiotic usage at the same time comparing with patients using antibiotics after SRP or SRP alone.


Assuntos
Antibacterianos/administração & dosagem , Periodontite Crônica/tratamento farmacológico , Periodontite Crônica/cirurgia , Desbridamento , Adulto , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Terapia Combinada , Raspagem Dentária , Quimioterapia Combinada , Feminino , Humanos , Masculino , Metronidazol/uso terapêutico , Pessoa de Meia-Idade
16.
J Exp Biol ; 217(Pt 10): 1656-66, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24829323

RESUMO

Although the functional properties of shark skin have been of considerable interest to both biologists and engineers because of the complex hydrodynamic effects of surface roughness, no study to date has successfully fabricated a flexible biomimetic shark skin that allows detailed study of hydrodynamic function. We present the first study of the design, fabrication and hydrodynamic testing of a synthetic, flexible, shark skin membrane. A three-dimensional (3D) model of shark skin denticles was constructed using micro-CT imaging of the skin of the shortfin mako (Isurus oxyrinchus). Using 3D printing, thousands of rigid synthetic shark denticles were placed on flexible membranes in a controlled, linear-arrayed pattern. This flexible 3D printed shark skin model was then tested in water using a robotic flapping device that allowed us to either hold the models in a stationary position or move them dynamically at their self-propelled swimming speed. Compared with a smooth control model without denticles, the 3D printed shark skin showed increased swimming speed with reduced energy consumption under certain motion programs. For example, at a heave frequency of 1.5 Hz and an amplitude of ± 1 cm, swimming speed increased by 6.6% and the energy cost-of-transport was reduced by 5.9%. In addition, a leading-edge vortex with greater vorticity than the smooth control was generated by the 3D printed shark skin, which may explain the increased swimming speeds. The ability to fabricate synthetic biomimetic shark skin opens up a wide array of possible manipulations of surface roughness parameters, and the ability to examine the hydrodynamic consequences of diverse skin denticle shapes present in different shark species.


Assuntos
Materiais Biomiméticos/química , Tubarões/anatomia & histologia , Pele/ultraestrutura , Animais , Biomimética/métodos , Hidrodinâmica , Masculino , Modelos Anatômicos , Pele/anatomia & histologia , Natação
17.
Beijing Da Xue Xue Bao Yi Xue Ban ; 46(1): 35-8, 2014 Feb 18.
Artigo em Zh | MEDLINE | ID: mdl-24535344

RESUMO

OBJECTIVE: To retrospectively evaluate the efficiency of dental treatment under general anesthesia (GA) in child patients, and analyze the related factors. METHODS: The records of patients treated under GA in the Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, between Aug 2008 and Jun 2012 were collected and analyzed. Two hundred and twenty eight records were found, of which 111 patients under 18 years old who were recalled more than 3 months after GA were selected randomly. The unplanned treatments including caries, failed restoration, root canal treatment and space maintenance fall-off etc. were recorded and analyzed. The survival rate and median survival time of the teeth were calculated, and a multivariate analysis was performed by Cox proportional hazard model. RESULTS: Totally, there were 1 415 teeth treated under GA. The median survival time was 825 days, 77.0% of the teeth were present during their recall period. The median time of the first unplanned treatment was 215 days, and the failed restoration was the main reason for the unplanned treatment. Other factors such as the age at treatment, gender, total number of decayed teeth, reason for GA, and living place were found unassociated with the survival rate. CONCLUSION: The effect of dental treatment under GA is satisfied. Regular dental visit after GA is very important for children's dental health.


Assuntos
Anestesia Dentária , Anestesia Geral , Assistência Odontológica para Crianças , Criança , Cárie Dentária , Humanos , Estudos Retrospectivos , Tratamento do Canal Radicular
18.
Clin Transl Gastroenterol ; 15(1): e00652, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37795904

RESUMO

INTRODUCTION: Colonoscopy is currently considered as one of the principal techniques to diagnose the colorectal diseases. Admittedly, qualified bowel preparation before colonoscopy is a premise for high-quality examination. Lower quality bowel preparation might seriously impede visualization of the intestinal mucosa, resulting in missed and misdiagnosed intestinal lesions. Therefore, it is necessary to choose the appropriate oral laxative based on the guarantee of safety and efficacy. METHODS: This prospective randomized controlled study was conducted to compare lactulose oral solution and polyethylene glycol (PEG) electrolyte powder for bowel preparation using the following indicators: Boston Bowel Preparation Scale, Bowel Bubble Score, detection rate of adenoma and lesion, patients' satisfaction, and adverse effects. Our study investigated the suitability of 2 bowel preparation reagents for patients with different body mass indices mainly based on body mass index (BMI). RESULTS: In the lactulose group, there was a significant improvement in the quality of bowel preparation compared with those in the PEG group ( P < 0.05), especially in people with normal BMI and higher BMI. Compared with the PEG group, individuals in the lactulose group had a significantly higher adenoma detection rate (50% vs 33.5%, P < 0.05) and taste scores (8.82 vs 6.69, P < 0.05), as well as significantly fewer adverse reactions (6.5% vs 32.5%, P < 0.05). DISCUSSION: Lactulose oral solution is superior to PEG in bowel preparation quality and taste, especially in normal BMI and higher BMI groups. It can be used clinically as a potential and promising bowel preparation agent in the future. Clinical Trial registration number: ChiCTR2100054318.


Assuntos
Adenoma , Polietilenoglicóis , Humanos , Polietilenoglicóis/efeitos adversos , Lactulose/efeitos adversos , Catárticos/efeitos adversos , Índice de Massa Corporal , Estudos Prospectivos , Colonoscopia/métodos
19.
Int J Biol Macromol ; 273(Pt 2): 132811, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38825282

RESUMO

Atmospheric drying method for fabricating aerogels is considered the most promising way for casting aerogels on a large scale. However, the organic solvent exchange, remaining environmental pollution risk, is a crucial step in mitigating the impact of surface tension during the atmospheric drying process, especially for wet gel formed through the alkoxy-derived sol-gel process, such as melamine-formaldehyde resin (MF) aerogel. Herein, a tough polymer-assisted in situ polymerization was proposed to fabricate MF resin aerogel with a combination of mechanical toughness and strength, enabling it to withstand the capillary force during water evaporation. The monolithic MF resin aerogel through the sol-gel method can be directly prepared without additional network strengthening or organic solvent exchange. The resulting MF resin aerogel exhibits a homogeneous as well as hierarchical structure with macropores and mesopores (~6 µm and ~5 nm), high compressive modulus of 31.8 MPa, self-extinguishing property, and high-temperature thermal insulation with 97 % heat decrease for butane flame combustion. This work presents a straightforward and environmentally friendly method for fabricating MF resin aerogels with nanostructures and excellent performance in open conditions, exhibiting various applications.


Assuntos
Retardadores de Chama , Géis , Triazinas , Triazinas/química , Géis/química , Pressão , Solventes/química , Resinas Sintéticas/química , Dessecação/métodos , Porosidade , Polimerização
20.
Hepatogastroenterology ; 60(122): 301-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23160168

RESUMO

BACKGROUND/AIMS: Standard dose therapy with pegylated interferon α-2a (Peg-IFNα-2a) and ribavirin is not suitable for all patients because of the side effects. This study aims to evaluate the virological responses of low-dose but long-course Peg-IFNα-2a therapy compared with standard therapy. METHODOLOGY: Ninety patients with chronic hepatitis C were divided into three groups according to their tolerance to Peg-IFNα-2a. The courses of treatment were 96 or 48 weeks respectively in patients with HCV genotypes 1b or 2a in the 67.5 µg and 90 µg groups, and were 48 or 24 weeks in the 180 µg groups. Serum HCV RNA was quantified to determine RVR, EVR, SVR and ETR. RESULTS: There were no statistical differences in HCV RNA load, HCV genotype at the baseline of the three groups (p>0.05). The rates of RVR, EVR, SVR and ETR (no significant differences in each group), were 63.04%, 82.61%, 71.74% and 85.87% in all 92 patients. Genotype 1b (95% CI=11.97-82.89; p=0.0075) and RVR (95% CI=0.12-0.53; p<0.001) were important predictors of SVR. CONCLUSIONS: Patients with low-dose but long-course Peg-IFNα-2a therapy had similar virological responses compared to those with standard therapy. HCV genotype and RVR were independent predictors of SVR.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adulto , Idoso , Genótipo , Hepatite C/classificação , Hepatite C Crônica/virologia , Humanos , Pessoa de Meia-Idade , RNA Viral/sangue , Proteínas Recombinantes/uso terapêutico
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