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[PMID]:29374921
[Au] Autor:Xiao R; Huang YS; Lin GA; Yuan SA; Hu DS
[Ad] Endereço:Burn Center, the 159th Hospital of PLA, Zhumadian 463008, China.
[Ti] Título:[Effects of cardiac support on delayed resuscitation in extensively burned patients with shock].
[So] Source:Zhonghua Shao Shang Za Zhi;34(1):8-13, 2018 Jan 20.
[Is] ISSN:1009-2587
[Cp] País de publicação:China
[La] Idioma:chi
[Ab] Resumo:To explore the effects of cardiac support on delayed resuscitation in extensively burned patients with shock. Clinical data of 62 extensively burned patients with shock on admission, admitted to the 159th Hospital of PLA (hereinafter referred to as our hospital) from January 2012 to January 2017, were retrospectively analyzed. They were divided into cardiac support group ( =35) and control group ( =27) according to the use of deslanoside and ulinastatin. All patients were treated with routine fluid resuscitation based on the formula of the Third Military Medical University till post injury hour (PIH) 48. Patients in cardiac support group were given slow intravenous injection of deslanoside which was added in 20 mL 100 g/L glucose injection with first dose of 0.4 to 0.6 mg, 0.2 to 0.4 mg per 6 to 8 h, no more than 1.6 mg daily, and slow intravenous injection of 1×10(5)U ulinastatin which was added in 100 mL 50 g/L glucose injection, once per 12 h. Other treatments of patients in the two groups followed the same conventional procedures of our hospital. The following data of the two groups of patients were collected. (1) The data of urine volume per hour within PIH 48, heart rate, mean arterial pressure (MAP), central venous pressure (CVP), blood lactic acid, base excess, hematocrit, and albumin at PIH 48 were recorded. (2) The input volumes of electrolyte, colloid within the first and second 24 hours post burn and the total fluid input volumes within PIH 48 were recorded. (3) The data of creatine kinase, creatine kinase isoenzyme-MB, lactate dehydrogenase, total bile acid, alanine aminotransferase, aspartate aminotransferase, ß(2)-microglobulin, urea nitrogen, and creatinine at PIH 48 were recorded. (4) The complications including cardiac failure, pulmonary edema, pleural effusion, seroperitoneum, renal failure, sepsis, and death were also recorded. Data were processed with independent sample test, Fisher's exact test, Pearson chi-square test, or continuous correction chi-square test. (1) There were no statistically significant differences in urine volume within PIH 48, heart rate, MAP, CVP, hematocrit, or albumin at PIH 48 between the patients of two groups ( =0.150, 0.488, 0.805, 0.562, 1.742, 0.696, >0.05). While the levels of blood lactic acid and base excess were respectively (4.2±2.2) and (-4.3±2.0) mmol/L in patients of cardiac support group, which were significantly better than (5.9±1.7) and (-6.0±3.1) mmol/L in patients of control group ( =3.249, 2.480, <0.05 or <0.01). (2) There was no statistically significant difference in input volume of colloid within the first 24 hours post burn between the patients of two groups ( =0.642, >0.05). The input volume of electrolyte within the first 24 hours post burn, the input volumes of electrolyte and colloid within the second 24 hours post burn, and the total fluid input volume within PIH 48 of patients in cardiac support group were significantly less than those in control group ( =2.703, 4.223, 3.437, 2.515, <0.05 or <0.01). (3) The levels of creatine kinase, creatine kinase isoenzyme-MB, lactate dehydrogenase, total bile acid, alanine aminotransferase, aspartate aminotransferase, ß(2)-microglobulin, urea nitrogen, and creatinine of patients in cardiac support group at PIH 48 were significantly lower than those in control group ( =3.066, 3.963, 3.225, 2.943, 2.431, 3.084, 4.052, 2.915, 3.353, <0.05 or <0.01). (4) The occurrences of pleural effusion and seroperitoneum and mortality of patients in cardiac support group were significantly lower than those in control group ( (2)=5.514, 6.984, 4.798, <0.05 or <0.01). There were no statistically significant differences in cardiac failure, pulmonary edema, renal failure, and sepsis between the patients of two groups [ (2)=1.314 (sepsis), >0.05]. The cardiotonic and cardiac protection treatments in delayed resuscitation of extensively burned patients with shock contribute to improving the cellular anonic metabolism, reducing the volume of fluid resuscitation, and mitigating the ischemic and hypoxic damage to organs, so as to lay foundation for decreasing further complication incidences and mortality.
[Mh] Termos MeSH primário: Queimaduras
Ressuscitação
Choque
[Mh] Termos MeSH secundário: Coloides
Hidratação
Hematócrito
Seres Humanos
Edema Pulmonar
Estudos Retrospectivos
Sepse
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180306
[Lr] Data última revisão:
180306
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180129
[St] Status:MEDLINE
[do] DOI:10.3760/cma.j.issn.1009-2587.2018.01.003


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[PMID]:29478640
[Au] Autor:Guan Z; Tang XY; Nishimura T; Katou H; Liu HY; Qing J
[Ad] Endereço:Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China; Laboratory of Soil Physics and Soil Hydrology, Department of Biological and Environmental Engineering, Graduate School of Agricul
[Ti] Título:Surfactant-enhanced flushing enhances colloid transport and alters macroporosity in diesel-contaminated soil.
[So] Source:J Environ Sci (China);64:197-206, 2018 Feb.
[Is] ISSN:1001-0742
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Soil contamination by diesel has been often reported as a result of accidental spillage, leakage and inappropriate use. Surfactant-enhanced soil flushing is a common remediation technique for soils contaminated by hydrophobic organic chemicals. In this study, soil flushing with linear alkylbenzene sulfonates (LAS, an anionic surfactant) was conducted for intact columns (15cm in diameter and 12cm in length) of diesel-contaminated farmland purple soil aged for one year in the field. Dynamics of colloid concentration in column outflow during flushing, diesel removal rate and resulting soil macroporosity change by flushing were analyzed. Removal rate of n-alkanes (representing the diesel) varied with the depth of the topsoil in the range of 14%-96% while the n-alkanes present at low concentrations in the subsoil were completely removed by LAS-enhanced flushing. Much higher colloid concentrations and larger colloid sizes were observed during LAS flushing in column outflow compared to water flushing. The X-ray micro-computed tomography analysis of flushed and unflushed soil cores showed that the proportion of fine macropores (30-250µm in diameter) was reduced significantly by LAS flushing treatment. This phenomenon can be attributed to enhanced clogging of fine macropores by colloids which exhibited higher concentration due to better dispersion by LAS. It can be inferred from this study that the application of LAS-enhanced flushing technique in the purple soil region should be cautious regarding the possibility of rapid colloid-associated contaminant transport via preferential pathways in the subsurface and the clogging of water-conducting soil pores.
[Mh] Termos MeSH primário: Recuperação e Remediação Ambiental/métodos
Gasolina/análise
Poluição por Petróleo/análise
Poluentes do Solo/química
Tensoativos/química
[Mh] Termos MeSH secundário: Coloides/química
Porosidade
Solo/química
Poluentes do Solo/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids); 0 (Gasoline); 0 (Soil); 0 (Soil Pollutants); 0 (Surface-Active Agents)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180301
[Lr] Data última revisão:
180301
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180227
[St] Status:MEDLINE


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[PMID]:28470522
[Au] Autor:Christ B; Fey C; Cubukova A; Walles H; Dembski S; Metzger M
[Ad] Endereço:Translational Center Würzburg "Regenerative Therapies for Oncology and Musculosceletal Diseases", Branch of Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB, Würzburg, 97070, Germany.
[Ti] Título:Screening Applications to Test Cellular Fitness in Transwell Models After Nanoparticle Treatment.
[So] Source:Methods Mol Biol;1601:111-122, 2017.
[Is] ISSN:1940-6029
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Nanoparticles (NPs) in biotechnology hold great promise for revolutionizing medical treatments and therapies. In order to bring NPs into clinical application there is a number of preclinical in vitro and in vivo tests, which have to be applied before. The initial in vitro evaluation includes a detailed physicochemical characterization as well as biocompatibility tests, among others. For determination of biocompatibility at the cellular level, the correct choice of the in vitro assay as well as NP pretreatment is absolutely essential. There are a variety of assay technologies available that use standard plate readers to measure metabolic markers to estimate the number of viable cells in culture. Each cell viability assay has its own set of advantages and disadvantages. Regardless of the assay method chosen, the major factors critical for reproducibility and success include: (1) choosing the right assay after comparing optical NP properties with the read-out method of the assay, (2) verifying colloidal stability of NPs in cell culture media, (3) preparing a sterile and stable NP dispersion in cell culture media used in the assay, (4) using a tightly controlled and consistent cell model allowing appropriate characterization of NPs. This chapter will briefly summarize these different critical points, which can occur during biocompatibility screening applications of NPs.
[Mh] Termos MeSH primário: Sobrevivência Celular/efeitos dos fármacos
Teste de Materiais/métodos
Nanopartículas/química
Nanopartículas/toxicidade
[Mh] Termos MeSH secundário: Células CACO-2
Coloides/química
Meios de Cultura/química
Espectroscopia Dielétrica
Sistemas de Liberação de Medicamentos
Seres Humanos
Concentração de Íons de Hidrogênio
Tamanho da Partícula
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids); 0 (Culture Media)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180219
[Lr] Data última revisão:
180219
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE
[do] DOI:10.1007/978-1-4939-6960-9_10


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[PMID]:29378097
[Au] Autor:Shumakova; Shipelin VA; Sidorova YS; Trushina EN; Mustafina OK; Pridvorova SM; Gmoshinsky IV; Khotimchenko SA
[Ti] Título:[Toxicological evaluation of nanosized colloidal silver, stabilized with polyvinylpyrrolidone. I. Characterization of nanomaterial, integral, hematological parameters, level of thiol compounds and liver cell apoptosis].
[So] Source:Vopr Pitan;84(6):46-57, 2015.
[Is] ISSN:0042-8833
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:Nano-sized colloidal silver (NCS) is currently one of the most widely used nanomaterials in medicine and consumer's products. Nanoparticles (NPs) of silver, in addition to the direct exposition through products may expose human via various environmental objects. The aim of the study is to assess the safe doses of silver NP received orally. The investigated NCS contained silver NPs with diameter of 10­60 nm, predominantly with a nearly spherical form stabilized with polyvinylpyrrolidone (PVP). The experiment was performed during 92 days in 5 groups of male Wistar rats (n=15 in each group), receiving a balanced semisynthetic diet. Animal of group 1 (control) received vehicle (deionized water) intragastrically for 30 days and then with food, groups from 2nd to 4th ­ PVP and groups from 3rd to 5th NCS, in doses respectively, 0.1; 1.0 and 10 mg/kg body weight (b.w.) in terms of silver. The dose of PVP in groups from 2nd to 5th did not differ, amounting to 200 mg/kg b.w. During the experiment, the weight gain, skin condition, activity, stool, cognitive function were assessed. At the end of the feeding period weight of internal organs, intestinal wall permeability to protein macromolecules, liver thiols, standard values of blood erythrocytes, leukocytes and platelets, hepatocyte apoptosis by flow cytometry were studied. These results suggest that in terms of weight gain, lung relative mass, average erythrocyte volume, hemoglobin content and concentration in erythrocytes, the relative proportion of lymphocytes and neutrophils adverse changes have been observed at a dose of 10 mg NPs per kg of b.w. At lower levels of exposure (0.1 and 1.0 mg/kg b.w.) some specific changes were also observed (in terms of thiols pool in liver, cognitive function, relative abundance of monocytes, the number of dead hepatocytes), which, however, did not possess an unambiguous dependence on the dose. Possible mechanisms of the toxic action of the NCS have been discussed.
[Mh] Termos MeSH primário: Apoptose/efeitos dos fármacos
Hepatócitos/metabolismo
Fígado/metabolismo
Nanopartículas Metálicas/toxicidade
Povidona/análogos & derivados
Prata/toxicidade
Compostos de Sulfidrila/metabolismo
[Mh] Termos MeSH secundário: Animais
Coloides
Hepatócitos/patologia
Fígado/patologia
Masculino
Nanopartículas Metálicas/química
Povidona/química
Povidona/toxicidade
Ratos
Ratos Wistar
Prata/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids); 0 (Sulfhydryl Compounds); 25249-54-1 (polyvinylpolypyrrolidone); 3M4G523W1G (Silver); FZ989GH94E (Povidone)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180216
[Lr] Data última revisão:
180216
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180130
[St] Status:MEDLINE


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[PMID]:29301069
[Au] Autor:Li Q; Zhao Z
[Ad] Endereço:College of Light Industry and Food Engineering, Guangxi University , Nanning, Guangxi 530004, People's Republic of China.
[Ti] Título:Characterization of the Structural and Colloidal Properties of α-Lactalbumin/Chitosan Complexes as a Function of Heating.
[So] Source:J Agric Food Chem;66(4):972-978, 2018 Jan 31.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This research investigated the interaction between α-lactalbumin (α-la) and chitosan at different temperatures. Chitosan was added to α-la solution (5 g L ) to achieve different α-la/chitosan ratios (8:1, 5:1, and 2:1), which were then subjected to different heating temperatures (20, 70, and 90 °C). The results indicated that a low amount of chitosan (8:1) precipitated α-la molecules. Increasing chitosan to a ratio of 5:1 resulted in exposure of the internal structure of α-la, and those formed complexes had high turbidity and average size, which were decreased by an increasing temperature. A further increase of chitosan to a ratio of 2:1 protected the internal structure of α-la molecules. All samples exhibited a similar adsorption behavior at the air/water interface, but the presence of chitosan significantly increased film elasticity. The produced complexes can be regarded as functional ingredients, which can be used as an emulsifying agent and a delivery material to control the release of bioactive compounds.
[Mh] Termos MeSH primário: Quitosana/química
Coloides/química
Temperatura Alta
Lactalbumina/química
[Mh] Termos MeSH secundário: Adsorção
Precipitação Química
Difusão Dinâmica da Luz
Elasticidade
Indústria Alimentícia
Nefelometria e Turbidimetria
Soluções
Espectrometria de Fluorescência
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids); 0 (Solutions); 9012-76-4 (Chitosan); 9013-90-5 (Lactalbumin)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180105
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b04628


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[PMID]:29381975
[Au] Autor:Han JW; Oh AY; Seo KS; Na HS; Koo BW; Lee YJ
[Ad] Endereço:Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do.
[Ti] Título:Comparison of intraoperative basal fluid requirements in distal pancreatectomy: Laparotomy vs. laparoscopy: A retrospective cohort study.
[So] Source:Medicine (Baltimore);96(47):e8763, 2017 Nov.
[Is] ISSN:1536-5964
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:There has been recent progress in intraoperative fluid therapy. However, little is known about intraoperative fluid therapy in laparoscopic surgery. The purpose of this study is to determine whether there are differences in the basal fluid requirements during surgery between laparotomy and laparoscopic distal pancreatectomy.This retrospective cohort study analyzed the electronic medical records of 253 patients who underwent distal pancreatectomy via either laparotomy (73 patients) or laparoscopy (180 patients) between June 2006 and March 2016. The volume of intraoperative fluid administered, postoperative complications, length of hospital stay, and readmission rate were evaluated. The total volume of fluids was calculated as the sum of the volume of crystalloid plus the volume of colloid multiplied by 1.5 or 2.0.Patients who had laparotomy were older and had higher American Society of Anesthesiologists classes. Anesthesia time was longer and estimated blood loss was larger in laparotomy. More colloid (1.8 mL/kg per h vs. 1.2 mL/kg per h, P < .001) and more total calculated fluid (1.5 times: 11.7 mL/kg per h vs. 10.6 mL/kg per h, P = .002; 2.0 times: 12.6 mL/kg per h vs. 11.2 mL/kg per h, P = .001) were infused in laparotomy. Crystalloid (9.0 mL/kg per h vs. 8.9 mL/kg per h, P = .203) did not show significant difference. Postoperative complications were more frequent (63% vs. 45%, P = .008), the hospital stay was longer (18 days vs. 13.4 days, P < .001), and readmission rate was higher (15% vs. 5.6%, P = .02) in laparotomy. By logistic regression analysis, we could find that operation type (laparotomy vs. laparoscopy, odds ratio 1.900, 95% confidence interval 1.072-3.368) and operation time (P = .004) had effect on complications.In patients undergoing distal pancreatectomy, basal fluid requirements were larger in laparotomy compared with laparoscopy. Operation time and estimated blood loss had effects on fluid administration. Postoperative complications were more frequent in laparotomy but we could not find relationships with infused colloid or total calculated fluid volumes. Operation type (laparotomy vs. laparoscopy) and operation time were the only related factors to postoperative complications.
[Mh] Termos MeSH primário: Hidratação/estatística & dados numéricos
Cuidados Intraoperatórios/métodos
Laparoscopia/métodos
Laparotomia/métodos
Pancreatectomia/métodos
[Mh] Termos MeSH secundário: Idoso
Coloides/uso terapêutico
Feminino
Hidratação/métodos
Seres Humanos
Soluções Isotônicas/uso terapêutico
Tempo de Internação
Masculino
Meia-Idade
Duração da Cirurgia
Complicações Pós-Operatórias/etiologia
Estudos Retrospectivos
Resultado do Tratamento
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids); 0 (Isotonic Solutions); 0 (crystalloid solutions)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180208
[Lr] Data última revisão:
180208
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:180201
[St] Status:MEDLINE
[do] DOI:10.1097/MD.0000000000008763


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[PMID]:28743275
[Au] Autor:Li J; Zou S; Gao J; Liang J; Zhou H; Liang L; Wu W
[Ad] Endereço:School of Chemical Engineering & Pharmaceutics, Henan University of Science & Technology, Luo Yang, 471023, China. Lijunbo@haust.edu.cn.
[Ti] Título:Block copolymer conjugated Au-coated Fe O nanoparticles as vectors for enhancing colloidal stability and cellular uptake.
[So] Source:J Nanobiotechnology;15(1):56, 2017 Jul 25.
[Is] ISSN:1477-3155
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Polymer surface-modified inorganic nanoparticles (NPs) provide a multifunctional platform for assisting gene delivery. Rational structure design for enhancing colloidal stability and cellular uptake is an important strategy in the development of safe and highly efficient gene vectors. RESULTS: Heterogeneous Au-coated Fe O (Fe O @Au) NPs capped by polyethylene glycol-b-poly1-(3-aminopropyl)-3-(2-methacryloyloxy propylimidazolium bromine) (PEG-b-PAMPImB-Fe O @Au) were prepared for DNA loading and magnetofection assays. The Au outer shell of the NPs is an effective platform for maintaining the superparamagnetism of Fe O and for PEG-b-PAMPImB binding via Au-S covalent bonds. By forming an electrostatic complex with DNA at the inner PAMPImB shell, the magnetic nanoplexes offer steric protection from the outer corona PEG, thereby promoting high colloidal stability. Transfection efficiency assays in human esophageal cancer cells (EC109) show that the nanoplexes have high transfection efficiency at a short incubation time in the presence of an external magnetic field, due to increased cellular internalization via magnetic acceleration. Finally, after transfection with the magnetic nanoplexes EC109 cells acquire magnetic properties, thus allowing for selective separation of transfected cells. CONCLUSION: Precisely engineered architectures based on neutral-cationic block copolymer-conjugated heterogeneous NPs provide a valuable strategy for improving the applicability and efficacy of synthesized vectors.
[Mh] Termos MeSH primário: Ouro/química
Imidazóis/química
Nanopartículas de Magnetita/química
Polietilenoglicóis/química
[Mh] Termos MeSH secundário: Linhagem Celular Tumoral
Sobrevivência Celular
Coloides
DNA/administração & dosagem
DNA/química
Sistemas de Liberação de Medicamentos
Liberação Controlada de Fármacos
Seres Humanos
Nanopartículas de Magnetita/toxicidade
Tamanho da Partícula
Propriedades de Superfície
Transfecção/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids); 0 (Imidazoles); 0 (Magnetite Nanoparticles); 0 (polyethylene glycol-b-poly1-(3-aminopropyl)-3-(2-methacryloyloxy propylimidazolium bromine)); 30IQX730WE (Polyethylene Glycols); 7440-57-5 (Gold); 9007-49-2 (DNA)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180115
[Lr] Data última revisão:
180115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.1186/s12951-017-0290-5


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[PMID]:29257676
[Au] Autor:Oleshkevich E; Teixidor F; Rosell A; Viñas C
[Ad] Endereço:Institut de Ciència de Materials de Barcelona (ICMAB-CSIC) , Campus UAB, 08193 Bellaterra, Spain.
[Ti] Título:Merging Icosahedral Boron Clusters and Magnetic Nanoparticles: Aiming toward Multifunctional Nanohybrid Materials.
[So] Source:Inorg Chem;57(1):462-470, 2018 Jan 02.
[Is] ISSN:1520-510X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:All-inorganic-made nanohybrid icosahedral boron cluster magnetic nanoparticles have been prepared. These magnetic nanoparticles (MNPs) consist of a magnetic core and an inorganic carboranylphosphinate shell. The phosphinate is directly bonded to the iron atoms of the surface in a bidentated coordination mode. The nanoparticles have been characterized by TEM, X-ray powder diffraction, infrared spectroscopy, energy dispersive X-ray analysis, high resolution X-ray photoelectron spectroscopy, magnetometry measurements, and redox titration, among other techniques. These studies have led to a composition (1-OPH(O)-1,7-closo-C B H ) (2Fe O ·Fe O ) that implies a surface coverage of 61.3 ± 7.4% by the ligand. When these MNPs go through sterilization in one autoclave, the magnetic hysteresis studies suggest minimal change before and after sterilization; this could erroneously indicate that there have not been any changes in the MNP composition. However, the Fe titration demonstrates that after sterilization only 1/7 of the Fe is Fe , leading to a core formula of Fe O ·2Fe O with a concomitant loss of ligand to a final ratio of 1:70 (carborane: Fe), and a final coverage by the ligand of 11.2 ± 1.4%. These studies bring relevant information on the behavior of the widely used MNPs and clearly show how the sterilization process needed for biological tests may alter the composition of the core and the loading of a peripheral ligand. In the particular case reported here, the liberated ligand has not been oxidized nor altered through the sterilization process.
[Mh] Termos MeSH primário: Boro/química
Nanopartículas de Magnetita/química
[Mh] Termos MeSH secundário: Coloides/síntese química
Coloides/química
Hidrodinâmica
Estrutura Molecular
Tamanho da Partícula
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids); 0 (Magnetite Nanoparticles); N9E3X5056Q (Boron)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180109
[Lr] Data última revisão:
180109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171220
[St] Status:MEDLINE
[do] DOI:10.1021/acs.inorgchem.7b02691


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[PMID]:27776240
[Au] Autor:McNew CP; Kananizadeh N; Li Y; LeBoeuf EJ
[Ad] Endereço:Land, Air, and Water Resources, University of California Davis, Davis, CA 95616, USA; Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN 37235, USA.
[Ti] Título:The attachment of colloidal particles to environmentally relevant surfaces and the effect of particle shape.
[So] Source:Chemosphere;168:65-79, 2017 Feb.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Despite the prevalence of nonspherical colloidal particles, the role of particle shape in the transport of colloids is largely understudied. This study investigates the attachment of colloidal particles onto environmentally relevant surfaces while varying particle shape and ionic strength. Using quartz crystal microbalance and atomic force microscopy measurements, the role of particle shape was elucidated and possible mechanisms discussed. The attachment of both spherical and stretched polystyrene colloidal particles onto a smooth alginate-coated silica surface showed qualitative agreement with DLVO theory. Attachment onto a Harpeth humic acid (HHA) surface, however, significantly deviated from DLVO theory due to its high surface heterogeneity and extended confirmation from the silica surface. This extended confirmation provided increased potential for spherical particle entanglement, while the enlarged major axis of the stretched particles hindered their ability to attach. As ionic strength increased, the HHA layer condensed and provided less potential for spherical particle entanglement and therefore the selectivity for spherical particle attachment vanished. The findings presented in this study suggest that colloidal particle shape may play a complex and important role in predicting the transport of colloidal particles, especially in the presence of natural organic matter-coated surfaces.
[Mh] Termos MeSH primário: Coloides/química
Monitoramento Ambiental/métodos
Substâncias Húmicas/análise
[Mh] Termos MeSH secundário: Alginatos
Monitoramento Ambiental/instrumentação
Ácido Glucurônico
Ácidos Hexurônicos
Microscopia de Força Atômica/métodos
Microesferas
Modelos Teóricos
Concentração Osmolar
Tamanho da Partícula
Técnicas de Microbalança de Cristal de Quartzo/métodos
Dióxido de Silício
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alginates); 0 (Colloids); 0 (Hexuronic Acids); 0 (Humic Substances); 7631-86-9 (Silicon Dioxide); 8A5D83Q4RW (Glucuronic Acid); 8C3Z4148WZ (alginic acid)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:171212
[Lr] Data última revisão:
171212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161025
[St] Status:MEDLINE


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[PMID]:28869625
[Au] Autor:Nakonieczny DS; Paszenda ZK; Basiaga M; Radko T; Drewniak S; Podwórny J; Bogacz W
[Ad] Endereço:Department of Biomaterials and Medical Devices Engineering, Faculty of Biomedical Engineering, Silesian University of Technology, Zabrze, Poland.
[Ti] Título:Phase composition and morphology characteristics of ceria-stabilized zirconia powders obtained via sol-gel method with various pH conditions.
[So] Source:Acta Bioeng Biomech;19(2):21-30, 2017.
[Is] ISSN:1509-409X
[Cp] País de publicação:Poland
[La] Idioma:eng
[Ab] Resumo:PURPOSE: High purity, fine crystalline, degradation-free at low temperature powders have attracted special interest in CAD/CAM prosthetic dentistry full ceramic restorations. This study reports the preparation and characterisation of zirconia-ceria (0.9 ZrO2 0.1 CeO2) powders. Materials were obtained from zirconium-n-alkoxide and cerium nitrate hexahydrate in the pH 2-4 and 8-10. METHODS: Zirconia- ceria powders were obtained with the sol-gel method in a humid-free environment. Thermal analysis (TGA/DTA) of the as-prepared materials was made for an assessment of its behaviour at elevated temperatures. Specimens were dried at 80 °C and calcinated in two stages: at 300 °C with soaking time 2.5 h and 850 °C with holding time 2.5 h, in order to evaluate the phase transformations. Thermal analyses of the as-dried powders were made for an assessment of its thermal behaviour during heat treatment up to 1000 °C. By X-ray diffraction (XRD), polymorphs of ZrO2 were identified. Additionally, scanning electron microscopy (SEM) and laser particle size distribution (PSD) were involved for characterisation of morphology of the powders. RESULTS: A correlation between the pH of the colloidal system and the morphology of the as-obtained powders were found. Based on analysis (SEM, PSD), structures were identified known as soft and hard agglomerates. CONCLUSIONS: It can be stated that differences found between powder morphology were dependent on the value pH used, which can be crucial for powder densification during sintering and compacting green bodies which, as a consequence, may be crucial for the lifetime of zirconia prostheses. Correlations between phase composition and pH are difficult to grasp, and require further, more sophisticated, studies.
[Mh] Termos MeSH primário: Cério/química
Coloides/química
Materiais Dentários/síntese química
Excipientes/química
Nanocompostos/química
Nanocompostos/ultraestrutura
Zircônio/química
[Mh] Termos MeSH secundário: Concentração de Íons de Hidrogênio
Teste de Materiais
Tamanho da Partícula
Transição de Fase
Pós
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids); 0 (Dental Materials); 0 (Excipients); 0 (Powders); 30K4522N6T (Cerium); 619G5K328Y (ceric oxide); C6V6S92N3C (Zirconium); S38N85C5G0 (zirconium oxide)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170905
[St] Status:MEDLINE



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