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1.
Clin Oral Investig ; 25(4): 2419-2427, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32910263

RESUMO

OBJECTIVE: To translate and cross-culturally adapt the Malocclusion Impact Questionnaire (MIQ) into Chinese and to assess the psychometric properties of the Chinese version of the MIQ (MIQ/C) for use among adolescents with malocclusion in China. MATERIALS AND METHOD: First, the MIQ/C was developed according to international guidelines. Then, the MIQ/C was filled out by 536 adolescents between 10 and 16 years of age. This study used exploratory factor analysis (EFA), confirmatory factor analysis (CFA), convergent validity, internal consistency, and test-retest reliability to evaluate the psychometric properties of the MIQ/C. RESULTS: Following EFA, three domains were extracted, accounting for 65.950% of the total variance. The CFA results showed that the fit indices of each factor in the three-factor model all reached the standard (chi-square/DF = 2.591, GFI = 0.919, TLI = 0.926, CFI = 0.928, RMSEA = 0.076). The scale evidenced a good relationship with the two global questions, indicating good convergent validity. The Cronbach alpha value and the intraclass correlation coefficients (ICC) value of the MIQ/C were 0.929 and 0.893, respectively. CONCLUSION: The MIQ/C demonstrated good reliability and validity and can be further studied and applied in Chinese adolescents with malocclusion. CLINICAL RELEVANCE: The MIQ/C can be applied to assess the psychosocial impact of malocclusion among Chinese adolescents.


Assuntos
Má Oclusão , Adolescente , China , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
2.
Odontology ; 109(4): 895-903, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34086131

RESUMO

Pulp regeneration with stem cells is a promising alternative for treating periapical and pulp diseases of young permanent teeth. The aim of this study was to characterize decellularized dental pulp extracellular matrix (dECM) and investigate whether bone morphogenetic protein 4 (BMP4) regulates dental pulp stromal cells (DPSC)-mediated pulp regeneration combined with dECM. Dental pulp isolated from healthy third molars was decellularized with 10% sodium dodecyl sulfate (SDS) and Triton X-100. H&E staining, DAPI staining and electron microscopy were used to observe the dECM structure. The Cell Counting Kit-8 assay was used to analyse cell proliferation. Recombinant adenovirus was used to overexpress BMP4 in DPSCs. The cells were cultured in dECM and dECM + three-dimensional (3D) Vitrogel systems, and bone/dentin/angiogenesis marker expression was evaluated by real-time polymerase chain reaction (RT-PCR) and ALP staining. DPSCs mixed with dECM and BMP4 were transplanted into nude mice, and pulp-like tissue formation was evaluated. The expression of osteogenic and angioblastic genes was increased, and pulp-like tissue formed in vivo. Thus, dECM promotes DPSC proliferation, BMP4 and dECM together accelerate pulp-like tissue formation by DPSCs in vitro.


Assuntos
Polpa Dentária , Regeneração , Animais , Proteína Morfogenética Óssea 4 , Diferenciação Celular , Humanos , Camundongos , Camundongos Nus , Células Estromais
3.
J Clin Periodontol ; 47(10): 1201-1208, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32767566

RESUMO

AIM: Building on previous psychometric work, we aimed to further assess the minimally important difference (MID) of the Oral Health Impact Profile for Chronic Periodontitis (OHIP-CP). METHODS: In total, 240 consecutive patients with chronic periodontitis were recruited in the study. The OHIP-CP was completed at baseline and after six weeks. Methodology testing included the confirmatory factor analysis (CFA) and MID. Confirmatory factor analysis (CFA) was performed to assess the fit of the previously proposed three-factor model. The MID of this questionnaire was determined by applying anchor-based and distribution-based approaches. RESULTS: The CFA supported a three-factor model for the OHIP-CP with acceptable fit to the data. The fit indices were χ2 /df = 2.231, GFI = 0.935, TLI = 0.969 and CFI = 0.976, RMSEA = 0.076. The OHIP-CP scores showed significant improvements after treatment (p < .001). The anchor-based MIDs of OHIP-CP for "oral function restriction," "oral pain" and "psychological and social impact," and total score were 2, 1, 4 and 7 points, respectively. The effect sizes (ES) and standardized response mean (SRM) for the OHIP-CP were moderate to large. CONCLUSIONS: The MID of the OHIP-CP is recommended for interpreting clinically meaningful change in oral health-related quality of life (OHRQoL) over time.


Assuntos
Periodontite Crônica , Humanos , Saúde Bucal , Dor , Qualidade de Vida , Inquéritos e Questionários
4.
Clin Oral Investig ; 24(6): 1997-2004, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31435823

RESUMO

OBJECTIVE: To assess dental treatment under dental general anesthesia (DGA) among Chinese preschool children by investigating changes in their oral health-related quality of life (OHRQoL), the incidence of postoperative complications, and parental satisfaction. METHOD: A single-center prospective cohort study was conducted. A total of 190 children who received treatment for early childhood caries (ECC) under DGA were included. The primary outcome was a change in the children's OHRQoL at 1 month after the operation compared to that at baseline, which was measured by the Early Childhood Oral Health Impact Scale (ECOHIS). The secondary outcomes were the incidence of complications within 1 day after treatment and parental satisfaction with the DGA treatment. RESULTS: In total, 180 participants were successfully reevaluated after the operation, yielding a 94.7% follow-up response rate. The total ECOHIS score decreased by 76.3% (P < 0.01) after treatment, demonstrating a large effect. Approximately 74.4% of the children complained of at least one complication, including sleepiness (43.3%), emergence agitation (38.9%), nausea/vomiting (13.9%), dizziness (10.6%), and fever (3.3%), on the first day. Approximately 85.5% of the parents were satisfied with the DGA treatment. CONCLUSION: DGA treatment has a positive effect on Chinese preschool children's OHRQoL and is evaluated highly by their parents. CLINICAL RELEVANCE: Dental treatment under general anesthesia improved the OHRQoL of Chinese preschool children.


Assuntos
Anestesia Dentária , Cárie Dentária , Saúde Bucal , Qualidade de Vida , Anestesia Geral , Criança , Pré-Escolar , Assistência Odontológica , Cárie Dentária/epidemiologia , Humanos , Pais , Estudos Prospectivos , Inquéritos e Questionários
5.
Int J Paediatr Dent ; 30(1): 50-56, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31520572

RESUMO

BACKGROUND: The Caries Impacts and Experiences Questionnaire for Children (CARIES-QC) is a newly developed child-centred caries-specific quality of life measure. AIM: We aimed to translate and adapt the CARIES-QC into Chinese and to validate the Chinese version of the CARIES-QC (CARIES-QC/C). DESIGN: The CARIES-QC/C was first produced according to international guidelines. Then, the CARIES-QC/C was distributed to children with active dental caries to evaluate its psychometric properties. Reliability of the CARIES-QC/C was investigated by internal consistency and test-retest reliability. Cross-cultural validity and convergent validity were performed to analyse the validity of the CARIES-QC/C. Cross-cultural validity was investigated using confirmatory factor analysis (CFA). RESULTS: A total of 206 children were recruited. Cronbach's alpha value of the CARIES-QC/C was .942, and the intraclass correlation coefficient (ICC) of the measure was .830. The CARIES-QC/C had an acceptable fit to the data in the one-factor model as confirmed by the CFA. The model fit parameters were chi-square/DF = 2.15, RMSEA = 0.07, GFI = 0.92, CFI = 0.98, and TLI = 0.96. For the convergent validity of the CARIES-QC/C, the measure evidenced good relationship with the global question. CONCLUSION: The CARIES-QC/C displays good reliability and validity through strict performance tests. This measure may be used as an effective tool in future clinical trials.


Assuntos
Cárie Dentária , Traduções , Criança , Humanos , Qualidade de Vida , Reprodutibilidade dos Testes , Inquéritos e Questionários
6.
Int J Med Sci ; 16(4): 567-575, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31171908

RESUMO

Bone tissue engineering requires a combination of cells, efficient biochemical and physicochemical factors, and biocompatible scaffolds. In this study, we evaluated the potential use of injectable Matrigel as a scaffold for the delivery of rat dental follicle stem/precursor cells (rDFSCs) transduced by bone morphogenetic protein (BMP) 9 to enhance osteogenic differentiation in vitro and promote ectopic bone formation in vivo. Recombinant adenovirus was used to overexpress BMP9 in rDFSCs. Alkaline phosphatase activity was measured using a histochemical staining assay and a chemiluminescence assay kit. Quantitative real-time polymerase chain reaction was used to determine mRNA expression levels of bone-related genes including distal-less homeobox 5 (DLX5), osteopontin (OPN), osterix (Osx), and runt-related transcription factor 2 (Runx2). Matrix mineralization was examined by Alizarin Red S staining. rDFSCs proliferation was analyzed using the Cell Counting Kit-8 assay. Subcutaneous implantation of rDFSCs-containing Matrigel scaffolds was used, and micro-computed tomography analysis, histological evaluation, and trichrome staining of implants extracted at 6 weeks were performed. We found that BMP9 enhanced alkaline phosphatase activity and mineralization in rDFSCs. The expression of bone-related genes (DLX5, OPN, Osx, and Runx2) was also increased as a result of BMP9 stimulation. Micro-computed tomography analysis and histological evaluation revealed that the bone masses retrieved from BMP9-overexpressing rDFSCs were significantly more pronounced in those with than in those without Matrigel. Our results suggest that BMP9 effectively promote osteogenic differentiation of rDFSCs, and Matrigel facilitate BMP9-induced osteogenesis of rDFSCs in vivo.


Assuntos
Fator 2 de Diferenciação de Crescimento/genética , Osteogênese/efeitos dos fármacos , Transplante de Células-Tronco , Alicerces Teciduais , Animais , Diferenciação Celular/efeitos dos fármacos , Colágeno/farmacologia , Saco Dentário/citologia , Combinação de Medicamentos , Fator 2 de Diferenciação de Crescimento/farmacologia , Humanos , Laminina/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/genética , Proteoglicanas/farmacologia , Ratos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Engenharia Tecidual , Microtomografia por Raio-X
7.
BMC Oral Health ; 19(1): 216, 2019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31590650

RESUMO

BACKGROUND: The resin bond strength of sclerotic dentine is significantly lower than that of the normal dentine, which paused a challenge for bonding procedures clinically. The aim of this study was to compare the effects of different surface pretreatments on the micro-tensile bond strength and microstructure between sclerotic dentine and normal dentine. METHODS: Eighty teeth that were collected, forty premolars with typical wedge-shaped defects visually graded as class III were assigned as the sclerotic dentine group (SD), the other forty normal premolars with artificial wedge-shaped defects were assigned as the normal dentine group (ND). Each group was randomly subdivided into eight subgroups according to the solution used: 35% phosphoric acid, 15% EDTA, 5% or 10% NaClO. Then the dentine surface was examined using a scanning electron microscope (SEM). The lesions were restored using self-etching adhesive and the subsequent resin composite. The teeth were sectioned into sticks for the micro-tensile bond strength analysis, and the data were analysed using the SPSS17.0 software package (α = 0.05). RESULTS: First, for the ND groups, after pretreatment using 35% phosphoric acid, and 35% phosphoric acid + 5% or 10% sodium hypochlorite, the bonding strengths of the normal dentine were higher than that of the other groups (P < 0.05). Second, for the SD groups, after pretreatment using 35% phosphoric acid, 15% EDTA, and 35% phosphoric acid + 5% or 10% sodium hypochlorite, the bonding strengths of the sclerotic dentine were higher than that of the other groups (P < 0.05). Third, the bond strengths of the sclerotic dentine were lower than that of the normal dentine without any pretreatment (P < 0.05). After pretreatment using 35% phosphoric acid + 5% or 10% sodium hypochlorite, the bonding strengths of the sclerotic dentine were higher than that of the normal dentine (P < 0.05). SEM observation showed that the appearances of dentine surface were changed after pretreatment using the above solutions, with the reduced smear layer, opened small groove and increased dentinal tubules. CONCLUSION: Pretreatment of dentine using 35% phosphoric acid+ 5% or + 10% sodium hypochlorite changed the microstructure of the sclerotic dentine surface and subsequently increased the micro-tensile bond strength.


Assuntos
Colagem Dentária , Adesivos Dentinários , Dentina , Condicionamento Ácido do Dente , Resinas Compostas , Teste de Materiais , Microscopia Eletrônica de Varredura , Cimentos de Resina , Propriedades de Superfície , Resistência à Tração
8.
J Clin Periodontol ; 44(6): 591-600, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28278366

RESUMO

AIM: The aim of this study was to develop and validate the first condition-specific tool to assess oral health-related quality of life (OHRQoL) impairment in association with chronic periodontitis and to use it as an outcome measure in clinical trials. METHODS: Twenty-three potential items were developed using a combined method consisting of a literature review, semi-structured patient interviews (n = 20) and expert panel 1. Subsequently, item selection was carried out by means of qualitative content analysis and quantitative classical test theory (CTT) with 110 patients and expert panel 2. Consequently, 18 items were selected and included in the final oral health impact profile for chronic periodontitis (OHIP-CP) instrument. The validity and reliability of the OHIP-CP were then examined. RESULTS: A total of 238 patients participated in the validation phase of OHIP-CP. The final 18-item questionnaire was shown to have a three-domain structure. The three components "pain and functional limitation", "psychological discomfort" and "psychological disability and social handicap" explained 49.9%, 9.9%, and 6.2% of the variance, respectively, together accounting for 66.1% of the variance. In addition, the OHIP-CP was shown to be valid in distinguishing patients with varying severity of chronic periodontitis. For the convergent validity, the reported impact of chronic periodontitis based on the OHIP-CP significantly correlated with the global oral health rating. All of its three domains were found to have good levels of internal consistency with Cronbach's alpha >.7, and excellent test-retest reliability. CONCLUSION: The OHIP-CP is the first condition-specific OHRQoL instrument for patients with chronic periodontitis. This short, reliable and valid questionnaire may serve as a valuable tool in future clinical trials.


Assuntos
Periodontite Crônica/fisiopatologia , Periodontite Crônica/psicologia , Saúde Bucal , Qualidade de Vida , Adolescente , Adulto , Idoso , Assistência Odontológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Reprodutibilidade dos Testes , Perfil de Impacto da Doença , Inquéritos e Questionários , Adulto Jovem
9.
Drug Dev Ind Pharm ; 42(1): 91-98, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25853294

RESUMO

In this study, the PEGylated nanostructured lipid carriers (PEG-NLC) were constructed for the intravenous delivery of 17-allylamino-17-demethoxygeldanamycin (17AAG). 17AAG-PEG-NLC was successfully prepared by the method of emulsion evaporation at a high temperature and solidification at a low temperature using a mixture of glycerol monostearate and PEG2000-stearate as solid lipids, and medium-chain triglyceride as the liquid lipid. The results revealed that the morphology of the NLC was spheroidal. The particle size, zeta potential and entrapment efficiency for 17AAG-PEG-NLC were observed as 189.4 nm, -20.2 mV and 83.42%, respectively. X-ray diffraction analysis revealed that 17AAG existed as amorphous structures in the nanoparticles. In the in vitro release study, the 17AAG from 17AAG-PEG-NLC exhibited a biphasic release pattern with burst release initially and sustained release afterwards. In addition, 17AAG-PEG-NLC showed a significantly higher in vitro antitumor efficacy and longer retention time in vivo than 17AAG solution. These results indicated that 17AAG-PEG-NLC may offer a promising alternative to the current 17AAG formulations for the treatment of solid tumors.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Benzoquinonas/administração & dosagem , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Lactamas Macrocíclicas/administração & dosagem , Administração Intravenosa , Animais , Antibióticos Antineoplásicos/farmacocinética , Benzoquinonas/farmacocinética , Varredura Diferencial de Calorimetria , Avaliação Pré-Clínica de Medicamentos , Emulsões , Glicerol/química , Humanos , Lactamas Macrocíclicas/farmacocinética , Lipídeos/química , Células MCF-7 , Nanopartículas/química , Tamanho da Partícula , Polietilenoglicóis/química , Ratos , Ratos Sprague-Dawley , Solubilidade , Estearatos/química , Triglicerídeos/química , Difração de Raios X
10.
Qual Life Res ; 24(4): 1011-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25298052

RESUMO

OBJECTIVES: The aim of this study was to evaluate the reliability and validity of the Chinese version of the Oral Health Impact Profile for edentulous subjects (OHIP-EDENT-C). METHODS: After translation and cross-cultural adaptation following international guidelines, 162 complete denture wearers were recruited to complete the questionnaire. The reliability of the OHIP-EDENT-C was evaluated using internal consistency and test-retest methods. The validity of the OHIP-EDENT-C was analyzed by construct validity and convergent validity. Construct validity was determined based on factor analysis and convergent validity by analyzing the correlation between OHIP-EDENT-C subscale scores and the global question. RESULTS: Cronbach's alpha value (internal reliability) for the total OHIP-EDENT-C score was 0.972, and the intraclass correlation coefficient value (test-retest reliability) was 0.763 (similar to the original OHIP-EDENT). Construct validity was determined by factor analysis, extracting five factors, accounting for 74.31 % of the variance. All items had factor loadings above 0.40. In terms of convergent validity, the OHIP-EDENT-C subscale was significantly highly correlated to the global question. CONCLUSION: The results suggest that the OHIP-EDENT-C is a reliable and valid measure to evaluate OHRQoL for edentulous subjects in China.


Assuntos
Boca Edêntula/psicologia , Saúde Bucal , Qualidade de Vida , Inquéritos e Questionários , Idoso , Povo Asiático , China , Prótese Total , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Traduções
11.
Qual Life Res ; 24(6): 1465-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25381644

RESUMO

OBJECTIVES: The aim of this study was to validate the short form of the Dentine Hypersensitivity Experience Questionnaire (DHEQ-15) in Chinese patients with dentine hypersensitivity (DH). METHODS: In total, 200 patients with DH were recruited to complete the questionnaire. The reliability of the DHEQ-15 was evaluated using internal consistency and test-retest methods. The exploratory factor analysis (EFA) was conducted to identify domains of the DHEQ-15. Convergent validity was determined by analyzing the correlation between DHEQ-15 subscale scores and the global rating of oral health question. RESULTS: Cronbach's alpha value (internal reliability) for the total DHEQ-15 score was 0.934 (higher to the original DHEQ-15' 0.924), and the intraclass correlation coefficient value (test-retest reliability) was 0.894 (lower to the original DHEQ-15' 0.939). The EFA identified three components with eigenvalues >1, explaining 53.0, 17.1, and 12.3% of the variance, respectively, accounting for a total of 82.4% of the variance. The three components named 'restrictions' (three items), 'changes in eating habits' (six items), and 'emotions and identity' (six items). In terms of convergent validity, the DHEQ-15 subscale was significant highly negatively correlated to the global oral health rating. CONCLUSIONS: The results provide initial evidence that the DHEQ-15 can be properly used for assessment of patients with DH in China.


Assuntos
Sensibilidade da Dentina/psicologia , Inquéritos e Questionários/normas , Adulto , Idoso , China , Sensibilidade da Dentina/diagnóstico , Emoções , Análise Fatorial , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Saúde Bucal , Qualidade de Vida , Reprodutibilidade dos Testes , Adulto Jovem
12.
Int J Biol Macromol ; 264(Pt 2): 130821, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484816

RESUMO

Cellulose nanofibers (CNF) based films are promising packaging materials, but the lack of special functions (especially UV-shielding property) usually restrict their further applications. In this work, MXene was incorporated into the CNF film by a direct solvent volatilization induced film forming method to study its UV-shielding property for the first time, which avoided the using of a vacuum filtration equipment. The composite films containing glycerin could be folded repeatedly without breaking, showing good flexibility. The structure and properties of MXene/CNF composite films (CMF) were characterized systematically. The results showed that MXene distributed uniformly in the CNF film matrix and there was strong hydrogen bonding interaction between CNF and MXene. The tensile strength and Young's modulus of the composite films could reach 117.5 MPa and 2.23 GPa, which was 54.1 % and 59.2 % higher than those of pure CNF film, respectively. With the increase of MXene content, both the UVA and UVB shielding percentages increased significantly from 17.2 % and 25.5 % to 100.0 %, showing excellent UV-shielding property. Moreover, CMF exhibited a low oxygen permeability (OP) value of 0.39 cc µm d-1 m-2 kPa-1, a low water vapor permeability (WVP) value of 5.13 × 10-11 g-1s-1Pa-1 and a high antibacterial rate against E. coli (94.1 % at 24 h), showing potential application in the packaging field.


Assuntos
Celulose , Nanofibras , Nitritos , Elementos de Transição , Celulose/química , Nanofibras/química , Escherichia coli , Embalagem de Produtos
13.
Sci Total Environ ; 913: 169787, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38181941

RESUMO

Microplastics (MPs) and polyhalogenated carbazoles (PHCZs) are widely detected in the aquatic environment, and their ecological risks have become a research focus. Although there is an extensive co-distribution of MPs and PHCZs, their combined toxicity to aquatic organisms is still unclear. This study investigated the toxic effects of polystyrene microplastics (PS-MPs) and 3,6-dibromocarbazole (3,6-DBCZ) on zebrafish embryos by individual/combined exposure. This study showed that individual or combined exposure of PS-MPs (10 mg/L) and 3,6-DBCZ (0.5 mg/L) could significantly increase the rate of zebrafish embryo deformity, whereas no significant effect was observed on mortality and hatching rate. Furthermore, exposure to 3,6-DBCZ or PS-MPs increased reactive oxygen species (ROS) levels in zebrafish embryos, and the resulting oxidative stress induced apoptosis. Comparably, the levels of oxidative stress and apoptosis in zebrafish embryos were significantly reduced with the combined exposure of 3,6-DBCZ and PS-MPs. These observations suggest that the combined exposure of 3,6-DBCZ and PS-MPs has an antagonistic effect on oxidative stress and apoptosis. Fluorescence PS-MPs tracing and 3,6-DBCZ enrichment analysis showed that, with the protection of chorion, the entry of PS-MPs (5 and 50 µm) into the embryonic stage (55 hpf) of zebrafish was prevented. Moreover, after exposure for 96-144 hpf, PS-MPs served as a carrier to promote the 3,6-DBCZ accumulation and its dioxin-like toxicity in zebrafish larvae through ingestion. Compared with 5-µm PS-MPs, 50-µm PS-MPs promoted higher accumulation and dioxin-like toxicity of 3,6-DBCZ in zebrafish larvae. These findings provide that MPs can be used as an important carrier of PHCZs, influencing their toxicity and bioaccumulation in the organisms.


Assuntos
Dioxinas , Dibenzodioxinas Policloradas , Poluentes Químicos da Água , Animais , Peixe-Zebra , Poliestirenos/toxicidade , Microplásticos/toxicidade , Plásticos/toxicidade , Carbazóis/toxicidade , Larva , Poluentes Químicos da Água/toxicidade
14.
Sci Total Environ ; 915: 170094, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38224880

RESUMO

Microplastics derived from polyethylene (PE) mulch films are widely found in farmland soils and present considerable potential threats to agricultural soil ecosystems. However, the influence of microplastics derived from PE mulch films, especially those derived from farmland residual PE mulch films, on soil ecosystems remains unclear. In this study, we analyzed the bacterial communities attached to farmland residual transparent PE mulch film (FRMF) collected from peanut fields and the different ecological effects of unused PE mulch film-derived microplastics (MPs) and FRMF-derived microplastics (MPs-aged) on the soil and earthworm Metaphire guillelmi gut microbiota, functional traits, and co-occurrence patterns. The results showed that the assembly and functional patterns of the bacterial communities attached to the FRMF were clearly distinct from those in the surrounding farmland soil, and the FRMF enriched some potential plastic-degrading and pathogenic bacteria, such as Nocardioidaceae, Clostridiaceae, Micrococcaceae, and Mycobacteriaceae. MPs substantially influenced the assembly and functional traits of soil bacterial communities; however, they only significantly changed the functional traits of earthworm gut bacterial communities. MPs-aged considerably affected the assembly and functional traits of both soil and earthworm gut bacterial communities. Notably, MPs had a more remarkable effect on nitrogen-related functions than the MPs-aged in numbers for both soil and earthworm gut samples. Co-occurrence network analysis revealed that both MPs and MPs-aged enhanced the synergistic interactions among operational taxonomic units (OTUs) of the composition networks for all samples. For community functional networks, MPs and MPs-aged enhanced the antagonistic interactions for soil samples; however, they exhibited contrasting effects for earthworm gut samples, as MPs enhanced the synergistic interactions among the functional contents. These findings broaden and deepen our understanding of the effects of FRMF-derived microplastics on soil ecosystems, suggesting that the harmful effects of aged plastics on the ecological environment should be considered.


Assuntos
Microbioma Gastrointestinal , Oligoquetos , Animais , Solo , Fazendas , Microplásticos , Plásticos , Ecossistema , Polietileno
15.
Int J Biol Macromol ; 259(Pt 1): 128891, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38143065

RESUMO

The toxic volatile organic compounds (VOCs), especially formaldehyde (FA), released from decoration materials pose a great threat to human health. In this study, formaldehyde adsorption performance of the specially formulated nanocellulose/chitosan aerogel (CNFCA) was investigated in simulated atmosphere. The physicochemical property of the composite aerogel was characterized, which had a large specific surface area (153.67 m2/g), a rough surface and an ultra-thin and porous structure. The composite aerogel showed excellent adsorption capacity for the formaldehyde, its theoretical maximum adsorption capacity was as high as 83.89 mg/g, and the adsorption process was more in accordance with the pseudo-second-order kinetics. The chromogenic reaction between the 4-amino-3-benzo-5-mercapto-1,2,4-triazolium (AHMT) and CNFCA was found that the color of the composite aerogel was depended on the free formaldehyde concentration. Based on this phenomenon, a colorimetric card was proposed and built to detection the formaldehyde in the atmosphere. Moreover, the adsorption mechanism research was found that the CNFCA with a multilayer structure belonged to physicochemical complex adsorption.


Assuntos
Quitosana , Humanos , Adsorção , Atmosfera , Celulose , Formaldeído
16.
Microb Cell Fact ; 12: 57, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23758664

RESUMO

BACKGROUND: Polylactic acid (PLA), a biodegradable polymer, has the potential to replace (at least partially) traditional petroleum-based plastics, minimizing "white pollution". However, cost-effective production of optically pure L-lactic acid is needed to achieve the full potential of PLA. Currently, starch-based glucose is used for L-lactic acid fermentation by lactic acid bacteria. Due to its competition with food resources, an alternative non-food substrate such as cellulosic biomass is needed for L-lactic acid fermentation. Nevertheless, the substrate (sugar stream) derived from cellulosic biomass contains significant amounts of xylose, which is unfermentable by most lactic acid bacteria. However, the microorganisms that do ferment xylose usually carry out heterolactic acid fermentation. As a result, an alternative strain should be developed for homofermentative production of optically pure L-lactic acid using cellulosic biomass. RESULTS: In this study, an ethanologenic Escherichia coli strain, SZ470 (ΔfrdBC ΔldhA ΔackA ΔpflB ΔpdhR ::pflBp6-acEF-lpd ΔmgsA), was reengineered for homofermentative production of L-lactic acid from xylose (1.2 mole xylose = > 2 mole L-lactic acid), by deleting the alcohol dehydrogenase gene (adhE) and integrating the L-lactate dehydrogenase gene (ldhL) of Pediococcus acidilactici. The resulting strain, WL203, was metabolically evolved further through serial transfers in screw-cap tubes containing xylose, resulting in the strain WL204 with improved anaerobic cell growth. When tested in 70 g L-1 xylose fermentation (complex medium), WL204 produced 62 g L-1 L-lactic acid, with a maximum production rate of 1.631 g L-1 h-1 and a yield of 97% based on xylose metabolized. HPLC analysis using a chiral column showed that an L-lactic acid optical purity of 99.5% was achieved by WL204. CONCLUSIONS: These results demonstrated that WL204 has the potential for homofermentative production of L-lactic acid using cellulosic biomass derived substrates, which contain a significant amount of xylose.


Assuntos
Escherichia coli/metabolismo , Ácido Láctico/biossíntese , Xilose/metabolismo , Álcool Desidrogenase/deficiência , Álcool Desidrogenase/genética , Proteínas de Bactérias/genética , Biomassa , Fermentação , Engenharia Genética , L-Lactato Desidrogenase/genética , Ácido Láctico/síntese química , Pediococcus/enzimologia , Pediococcus/genética , Plasmídeos/genética , Plasmídeos/metabolismo , Poliésteres , Polímeros/síntese química , Estereoisomerismo
17.
J Hazard Mater ; 460: 132367, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37633013

RESUMO

Flumetsulam (FLU) is a new class of broad-spectrum herbicides. With the widespread use of plastic products, polyethylene (PE) microplastics (MPs) may remain in the soil. It is possible for these two novel contaminants to co-exist in the soil environment. In the present study, we used brown soil as the test soil and determined the toxicity of FLU at 0.05, 0.5 and 2.5 mg kg-1 alone and in combination with PE MPs (1%) on soil microorganisms. The obtained results demonstrated that the exposure of FLU and FLU+MPs had an inhibitory effect on the numbers of bacteria and fungi. In addition, FLU and FLU+MPs caused changes in the relevant functional bacterial genera, favored nitrogen fixation and denitrification, and promoted soil carbon fixation, but inhibited nitrification. Compared to FLU exposure alone, exposure to FLU+MPs gave rise to significant differences in soil bacterial community composition, but did not affect carbon and nitrogen cycling. The integrated biomarker response results indicated that the toxicity of FLU and FLU+MPs to soil microorganisms increased with increasing concentrations of FLU. The present experiment clarified the toxicological effects of co-exposure of FLU and MPs on microorganisms and filled the toxicological data gap of FLU.


Assuntos
Microplásticos , Polietileno , Polietileno/toxicidade , Plásticos , Microbiologia do Solo , Ciclo do Nitrogênio , Carbono , Solo , Expressão Gênica
18.
J Hazard Mater ; 455: 131603, 2023 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-37182465

RESUMO

Microplastics (MPs) may significantly affect the bioavailability of coexisting pollutants in soil by adsorption-desorption behavior. However, the mechanisms underlying these interaction remain unclear. Herein, the influence of unused polythylene mulch film-derived MPs (MFMPs) and farmland residual polyethylene mulch film-derived MPs (MFMPs-aged) on the adsorption-desorption behavior and bioavailability of atrazine (ATZ) in soil were investigated. The adsorption kinetics and the adsorption isotherms of ATZ on soil, MFMPs, and MFMPs-aged fitted well by the pseudo-second-order model and the Langmuir model, respectively. ATZ were easier to desorb from soil, MFMPs, and MFMPs-aged in the simulated earthworm digestive fluid than that in the CaCl2 solution. The adsorption and desorption capacities of MFMPs and MFMPs-aged for ATZ were higher than those of soil, especially for MFMPs-aged. The existence of MPs in soil strengthened the adsorption and desorption capacities of ATZ, and the strengthened effects were promoted by the addition amount and aging process of MPs. Moreover, the occurrence of MPs significantly increased the bioaccumulation of ATZ in earthworms, especially for MFMPs-aged. This study deepens the knowledge of the interaction mechanisms of mulch film-derived MPs and pesticide pollution.


Assuntos
Atrazina , Oligoquetos , Poluentes do Solo , Animais , Microplásticos/toxicidade , Polietileno , Plásticos , Bioacumulação , Poluentes do Solo/análise , Solo
19.
Eur J Oral Sci ; 120(3): 218-23, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22607338

RESUMO

The aim of this study was to evaluate the reliability and the validity of the Chinese version of the Dentine Hypersensitivity Experience Questionnaire (DHEQ). After translation and cross-cultural adaptation following international guidelines, 110 patients with dentine hypersensitivity were recruited to complete the questionnaire. The reliability of the Chinese version of the DHEQ was evaluated using internal consistency and test-retest methods. Construct validity was determined based on factor analysis, discriminative validity (by comparing the subscale scores difference in the degree of sensitivity being investigated), and convergent validity (by analyzing the correlation between DHEQ subscale scores and the global rating of oral health question). Cronbach's alpha value (internal reliability) for the total DHEQ score was 0.95 and the intraclass correlation coefficient (ICC) value (test-retest reliability) was 0.85. Construct validity was determined by factor analysis, extracting eight factors, accounting for 74% of the variance. All items had factor loadings of >0.40. In addition, the Chinese version of the DHEQ was found to be valid for distinguishing patients with varying degrees of dentine hypersensitivity. In terms of convergent validity, the impact scale was significantly highly correlated to the global oral health rating. The results suggest that the Chinese version of the DHEQ has satisfactory psychometric properties and is applicable for patients with dentine hypersensitivity in China.


Assuntos
Efeitos Psicossociais da Doença , Sensibilidade da Dentina/psicologia , Psicometria/métodos , Qualidade de Vida , China , Comparação Transcultural , Inquéritos de Saúde Bucal , Humanos , Saúde Bucal , Reprodutibilidade dos Testes , Perfil de Impacto da Doença , Inquéritos e Questionários
20.
Community Dent Oral Epidemiol ; 50(3): 171-179, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33876436

RESUMO

OBJECTIVES: To establish and validate a short form of the self-management ability questionnaire (SMAQ) for chronic periodontitis patients. METHODS: A total of 480 chronic periodontitis patients were recruited and divided randomly in into two groups: development group and validation group. The item reduction process of the SMAQ was based on item response theory (IRT) and classical test theory (CTT). The resulting short form of the SMAQ was then validated using exploratory factor analysis (EFA), confirmatory factor analysis (CFA), convergent validity, internal consistency and test-retest reliability. RESULTS: The item reduction process produced a 12-item short-form SMAQ (SMAQ-12). EFA results on the twelve items extracted three factors consistent with the original SMAQ and CFA results demonstrated acceptable goodness-of-fit indices of this three-factor structure. Moreover, the SMAQ-12 scores had high correlations with the original measure (rs ≥0.904), good internal consistency and test-retest reliability. CONCLUSIONS: The SMAQ-12 is an easy-to-use, reliable and valid measure for assessing self-management ability in patients with chronic periodontitis.


Assuntos
Periodontite Crônica , Autogestão , Periodontite Crônica/terapia , Análise Fatorial , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
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