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1.
BMC Oral Health ; 22(1): 631, 2022 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-36550501

RESUMO

BACKGROUND: The purpose of this study was to evaluate the differences between buccolingual inclination (BI) of maxillary posterior teeth in patients with cleft lip and palate (CLP) and non-cleft palate with skeletal Class III malocclusion. We propose a method of maxillary expansion which is more suitable for patients with CLP. METHODS: For this retrospective study, 40 patients with CLP and 21 patients with skeletal Class III malocclusion were selected. The CLP group was divided into the unilateral cleft lip and palate (UCLP) and bilateral cleft lip and palate (BCLP) groups. The BI of the maxillary first premolar (BI4), maxillary second premolar (BI5) and first molar (BI6) were measured using cone-beam computed tomography, and the differences between them were compared and analyzed by Student's t-test. RESULTS: There were significant differences between cleft side BI4 and non-cleft side BI4 in the UCLP group, BI5 in the BCLP group, BI4 and BI5 in all CLP groups and the skeletal Class III malocclusion group. BI6 was similar across all three groups. CONCLUSIONS: The premolars of patients with CLP do not exhibit the same regularity as those with Class III malocclusion; this may be related to surgical scarring of the cleft palate. Greater attention should be paid to the correction of BI in the maxillary expansion of patients with CLP.


Assuntos
Fenda Labial , Fissura Palatina , Má Oclusão Classe III de Angle , Humanos , Fissura Palatina/diagnóstico por imagem , Fenda Labial/diagnóstico por imagem , Estudos Retrospectivos , Má Oclusão Classe III de Angle/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos
2.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(1): 112-119, 2022 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-35231972

RESUMO

Liposomes with precisely controlled composition are usually used as membrane model systems to investigate the fundamental interactions of membrane components under well-defined conditions. Hydration method is the most common method for liposome formation which is found to be influenced by composition of the medium. In this paper, the effects of small alcohol (ethanol) on the hydration of lipid molecules and the formation of liposomes were investigated, as well as its coexistence with sodium chloride. It was found that ethanol showed the opposite effect to that of sodium chloride on the hydration of lipid molecules and the formation of liposomes. The presence of ethanol promoted the formation of liposomes within a certain range of ethanol content, but that of sodium chloride suppressed the liposome formation. By investigating the fluorescence intensity and continuity of the swelled membranes as a function of contents of ethanol and sodium chloride, it was found that sodium chloride and ethanol showed the additive effect on the hydration of lipid molecules when they coexisted in the medium. The results may provide some reference for the efficient preparation of liposomes.


Assuntos
Etanol , Lipossomos , Etanol/farmacologia , Lipídeos
3.
Glob Chang Biol ; 26(6): 3356-3367, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32281177

RESUMO

Plastic pollution is a global concern given its prevalence in aquatic and terrestrial ecosystems. Studies have been conducted on the distribution and impact of plastic pollution in marine ecosystems, but little is known on terrestrial ecosystems. Plastic mulch has been widely used to increase crop yields worldwide, yet the impact of plastic residues in cropland soils to soil health and crop production in the long term remained unclear. In this paper, using a global meta-analysis, we found that the use of plastic mulch can indeed increase crop yields on average by 25%-42% in the immediate season due to the increase of soil temperature (+8%) and moisture (+17%). However, the unabated accumulation of film residues in the field negatively impacts its physicochemical properties linked to healthy soil and threatens food production in the long term. It has multiple negative impacts on plant growth including crop yield (at the mean rate of -3% for every additional 100 kg/ha of film residue), plant height (-2%) and root weight (-5%), and soil properties including soil water evaporation capacity (-2%), soil water infiltration rate (-8%), soil organic matter (-0.8%) and soil available phosphorus (-5%) based on meta-regression. Using a nationwide field survey of China, the largest user of plastic mulch worldwide, we found that plastic residue accumulation in cropland soils has reached 550,800 tonnes, with an estimated 6%-10% reduction in cotton yield in some polluted sites based on current level of plastic residue content. Immediate actions should be taken to ensure the recovery of plastic film mulch and limit further increase in film residue loading to maintain the sustainability of these croplands.


Assuntos
Agricultura , Plásticos , China , Produtos Agrícolas , Ecossistema , Abastecimento de Alimentos , Solo
4.
Int J Biol Macromol ; 255: 128254, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992922

RESUMO

Deacidification and strengthening play pivotal roles in the enduring conservation of aged paper. In this study, we innovatively propose the use of reduced cellulose nanofibrils (rCNFs) and aminopropyltriethoxysilane modified CaCO3 (APTES-CaCO3) for preserving aged paper. The sodium borohydride-mediated reduction of cellulose nanofibrils diminished the carboxylate content and O/C mass ratio in rCNFs, which in turn amplified the swelling of rCNFs and their crosslinking potential with paper fibers. By introducing amino groups to the CaCO3 surface, the dispersion property of APTES-CaCO3 in organic solvent was enhanced, as well as the deacidification ability and the retention on the paper. The distinct structures and attributes of rCNFs and APTES-CaCO3 were characterized by various techniques. Following the conservation application to aged paper using this system, a desired internal pH value of 8.31 and an alkaline reserve of 0.8056 mol/kg were achieved, alongside a 33.6 % elevation in the tensile index. The aging resistance of the treated paper was evaluated by dry heat and hygrothermal aging tests. The findings revealed that the treatment bestowed the treated paper with outstanding anti-aging properties, notably in terms of internal pH, alkaline reserve and mechanical robustness. Additionally, the paper's brightness was amplified, while its color alteration remained negligible.


Assuntos
Celulose , Nanofibras , Celulose/química , Nanofibras/química , Resistência à Tração , Propilaminas
5.
Int J Biol Macromol ; 162: 262-272, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32569688

RESUMO

The nano drug delivery system (NDDS) has been extensively investigated for cancer treatment because of its ability to enhance drug efficacy. However, there are only a few studies attempting NDDS for AZD9291 (Osimertinib). Here, we encapsulated AZD9291 in chitooligosaccharides (COS)-modified poly (lactic-co-glycolic acid) (PLGA) nanoparticles. COS, a cationic polymer, was used to develop positively charged nanoparticles with good biological affinity. The prepared AZD-PLGA-COS NPs exhibited a smaller particle size (176.6 ± 0.4 nm), a positively charged surface (+18.65 ± 0.38 mV), and an increased cellular uptake. The IC50 of H1975 cells was reduced by 45.90%, and the expression of p-EGFR, PARP, Bak, caspase-9, Bax, and Bcl-2 was regulated to promote cellular apoptosis. Furthermore, COS was found to inhibit the expression of immune checkpoint PD-L1. This study suggests that COS-modified PLGA nanoparticles with low toxicity and high encapsulation efficiency (EE) could potentially enhance drug efficacy.


Assuntos
Acrilamidas/farmacologia , Compostos de Anilina/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Quitina/análogos & derivados , Portadores de Fármacos/química , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Antígeno B7-H1/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quitina/química , Quitosana , Liberação Controlada de Fármacos , Receptores ErbB/metabolismo , Humanos , Concentração Inibidora 50 , Microscopia Eletrônica de Transmissão , Nanopartículas/toxicidade , Nanopartículas/ultraestrutura , Oligossacarídeos , Tamanho da Partícula , Poli(ADP-Ribose) Polimerase-1/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
6.
Metallomics ; 9(9): 1304-1315, 2017 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-28869270

RESUMO

Copper (Cu) was used in antiquity to prevent waterborne and food diseases because, as a broad-spectrum antimicrobial agent, it generates reactive oxygen species, ROS. New technologies incorporating Cu into low-cost biodegradable nanomaterials built on cellulose, known as cellulosic cupric nanoparticles or c-CuNPs, present novel approaches to deliver Cu in a controlled manner to control microbial growth. We challenged strains of Saccharomyces cerevisiae with soluble Cu and c-CuNPs to evaluate the potential of c-CuNPs as antifungal agents. Cells exposed to c-CuNPs demonstrated greater sensitivity to Cu than cells exposed to soluble Cu, although Cu-resistant strains were more tolerant than Cu-sensitive strains of c-CuNP exposure. At the same level of growth inhibition, 157 µM c-CuNPs led to the same internal Cu levels as did 400 µM CuSO4, offering evidence for alternative mechanisms of toxicity, perhaps through ß-arrestin dependent endocytosis, which was supported by flow cytometry and fluorescence microscopy of c-CuNPs distributed both on the cell surface and within the cytoplasm. Genes responsible for genetic variation in response to copper were mapped to the ZRT2 and the CUP1 loci. Through proteomic analyses, we found that the expression of other zinc (Zn) transporters increased in Cu-tolerant yeast compared to Cu-sensitive strains. Further, the addition of Zn at low levels increased the potency of c-CuNPs to inhibit even the most Cu-tolerant yeast. Through unbiased systems biological approaches, we identified Zn as a critical component of the yeast response to Cu and the addition of Zn increased the potency of the c-CuNPs.


Assuntos
Antifúngicos/toxicidade , Cobre/toxicidade , Nanopartículas Metálicas/toxicidade , Proteômica/métodos , Saccharomyces cerevisiae/efeitos dos fármacos , Antifúngicos/química , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Celulose/química , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Nanopartículas Metálicas/química , Metalotioneína/genética , Metalotioneína/metabolismo , Testes de Sensibilidade Microbiana , Proteoma/genética , Proteoma/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
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