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1.
Anim Cogn ; 26(4): 1353-1368, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37219737

RESUMEN

Comparing oneself to others is a key process in humans that allows individuals to gauge their performances and abilities and thus develop and calibrate their self-image. Little is known about its evolutionary foundations. A key feature of social comparison is the sensitivity to other individuals' performance. Recent studies on primates produced equivocal results, leading us to distinguish between a 'strong' variant of the social comparison hypothesis formulated for humans and a 'weak' variant found in non-human primates that would comprise some elements of human social comparison. Here, we focus on corvids that are distantly related to primates and renowned for their socio-cognitive skills. We were interested in whether crows' task performances were influenced (i) by the presence of a conspecific co-actor performing the same discrimination task and (ii) by the simulated acoustic cues of a putative co-actor performing better or worse than themselves. Crows reached a learning criterion quicker when tested simultaneously as compared to when tested alone, indicating a facilitating effect of social context. The performance of a putative co-actor influenced their performance: crows were better at discriminating familiar images when their co-actor was better than they were. Standard extremity (how pronounced the difference was between the performance of the subject and that of the co-actor), and category membership (affiliation status and sex), of the putative co-actors had no effect on their performance. Our findings are in line with the 'weak' variant of social comparison and indicate that elements of human social comparison can be found outside of primates.


Asunto(s)
Cuervos , Humanos , Animales , Comparación Social , Señales (Psicología) , Evolución Biológica , Primates
2.
Z Rheumatol ; 77(7): 633-636, 2018 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-30066026

RESUMEN

Chronic infantile neurological cutaneous and articular syndrome (CINCA) is a disorder with a defect in the CIAS1 (NLRP3) gene and the altered gene product cryopyrin leads to inflammasome activation with increased IL-1beta synthesis. The activation pathway of the transcription factor NF-κB is also affected, which plays a role in angiogenesis. With respect to the angiogenesis stimulating ability of prostaglandin E1, we treated a female patient with CINCA syndrome and conventionally non-responsive skin ulcers with prostaglandin E1 infusions (6 µg/kg bw/24 h/5 day) followed by wound healing lasting over 3 weeks. After 1 year of periodic infusions, the skin defects were permanently closed.


Asunto(s)
Alprostadil , Síndromes Periódicos Asociados a Criopirina , Úlcera Cutánea , Alprostadil/uso terapéutico , Síndromes Periódicos Asociados a Criopirina/complicaciones , Femenino , Humanos , Inflamasomas , Interleucina-1beta , Úlcera Cutánea/complicaciones , Úlcera Cutánea/tratamiento farmacológico
3.
Genet Mol Res ; 16(2)2017 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-28613375

RESUMEN

Mycophenolate mofetil (MMF) is a prodrug active only after its hydrolysis to mycophenolic acid (MPA). The UGT1A9 enzyme is of special interest since it is the main enzyme involved in the glucuronidation of MPA. Single nucleotide polymorphisms (SNPs) in the UGT1A9 gene may be responsible for individual differences in the pharmacokinetics of MMF. Expression levels and the activity of UGT1A9 may depend on the presence of some SNPs located in the gene promoter region (-2152C>T and -275T>A), as well as changes in the coding region (c.98T>C). The objective of this study was to evaluate the effect of allelic variants of the UGT1A9 c.98T>C polymorphism (rs72551330; g. 87289T>C) on MMF metabolism in renal transplant patients. MPA and MPA 7-O glucuronide (MPAG) levels were determined on plasma samples of kidney transplant patients (N = 39) by high-performance liquid chromatography using ultraviolet detection. DNA was isolated from leukocytes and stored at -20°C. The presence of SNPs was investigated using polymerase chain reaction, followed by amplicon sequencing. The analysis of the UGT1A9 c.98T>C polymorphism revealed that all study patients presented the TT genotype. Diverse MPA and MPAG plasma concentrations were detected, including therapeutic, subtherapeutic, and toxic levels. A standardized molecular method permitted identification of UGT1A9 c.98T>C polymorphism genotypes in the examined renal transplant patients. All individuals of the study group presented the same genotype (c.98TT) for that polymorphism. Thereby, no association between the c.98T>C polymorphism and MPA and MPAG plasma levels could be evaluated, despite different levels of these compounds being observed.


Asunto(s)
Glucurónidos/sangre , Glucuronosiltransferasa/genética , Rechazo de Injerto/sangre , Trasplante de Riñón/efectos adversos , Ácido Micofenólico/análogos & derivados , Polimorfismo de Nucleótido Simple , Adulto , Femenino , Glucurónidos/genética , Rechazo de Injerto/genética , Humanos , Masculino , Persona de Mediana Edad , Ácido Micofenólico/sangre , UDP Glucuronosiltransferasa 1A9
4.
Soft Matter ; 13(1): 170-180, 2016 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-27453506

RESUMEN

We investigate the drainage dynamics of thin liquid foam films containing PNiPAM microgel suspensions with two cross-linking densities (1.5 and 5 mol% BIS) and at two microgel concentrations (0.1 and 1% wt). For this purpose, we use a thin-film pressure balance apparatus that can apply a controlled and sudden hydrostatic pressure on a film, and record the subsequent film thinning as a function of time. Once the film thickness has reached a stationary value, we test the adhesion between the interfaces of the film by reducing the pressure and measuring the angle between the film and the meniscus. This angle increases on reduction of pressure for adhesive films, which resists the separation of their interfaces. Non-adhesive films separate easily, and the meniscus angle stays constant. At a low microgel concentration, the more densely cross-linked microgels (5 mol% BIS) tend to drain into more adhesive films than the more loosely cross-linked particles (1.5 mol% BIS). The adhesion results from particles that bridge the two air-water interfaces of the film and are shared between them. In these cases, the film, which is initially stabilized by a bilayer of microgel particles, rearrange to a state where the microgels bridge the interfaces. These results are discussed and compared with previous studies at a low concentration of microgels, which have shown that emulsions stabilized with densely cross-linked microgels are more adhesive and less resistant to mechanical stresses than those obtained with lower cross-linking densities. In addition, micron-scale depleted zones with no microgels are observed in the films stabilized with the 5 mol% BIS particles, which eventually lead to the rupture of the films. At 1% wt, the films drain slowly, are not adhesive and have the thickness of a bilayer of microgel; while at 0.1% wt, the films have the thickness of a monolayer of microgel, are adhesive and show bridging. From the thin liquid foam film thicknesses we extract a rough estimation of the radii of adsorbed particles in the thick films before applying the pressure. Our results are consistent with particles being adsorbed in a spread conformation for the 0.1% wt sample and in a compressed conformation for the 1% wt sample. In line with previous studies on emulsions, we conclude that a larger surface coverage may reduce rearrangements, thus preventing bridging.

5.
Bioresour Technol ; 393: 130091, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37995874

RESUMEN

Recently, numerous experimental studies have been undertaken to understand the interactions between different feedstocks in anaerobic digestion. They have unveiled the potential of blending substrates in the process. Nevertheless, these experiments are time-intensive, prompting the exploration of various optimization approaches. Notably, genetic algorithms have gained interest due to their population-based structures allowing them to efficiently yield multiple Pareto-optimal solutions in a single run. This study uses a simplified static anaerobic co-digestion model as the fitness function for a multi-objective optimization. The optimization aims to achieve a methane production set-point while reducing the output ammonia nitrogen and increasing the recipe' profitability. Thus, the study employs genetic algorithms to identify Pareto fronts and constraints confined the solution space within feasible boundaries. It also underscores the influence of economic considerations on the viable solution space. Ultimately, the optimal feed recipe not only ensures stable operations within the digester but also enhances associated profits.


Asunto(s)
Reactores Biológicos , Metano , Anaerobiosis , Modelos Teóricos , Algoritmos
6.
Sci Rep ; 14(1): 3378, 2024 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336814

RESUMEN

This study evaluates the ideal pH for anti-erosion and anti-adherent efficacy of fluoride and stannous solutions (sodium fluoride (SF), amine fluoride (AF), sodium monofluorophosphate (SMFP), stannous fluoride (SnF2) with 500 ppm fluoride concentration each and stannous chloride (SnCl2, 1563 ppm stannous)). In vitro, solutions were tested at pH 4.5 and 5.5. The main in situ experiments were carried out at the pH of 4.5: For pellicle formation 6 volunteers wore bovine enamel slabs intraorally for 1 min, rinsed with 8 ml solution for 1 min and continued for up to 30 min/8 h. Physiological pellicle samples served as controls. After incubation in HCl (2.0, 2.3) for 2 min mineral release was determined photometrically. Bacterial counts on 8 h biofilms were determined by fluorescence microscopy (BacLight™ and DAPI with Concanavalin A). Modification of the pellicle ultrastructure was examined by TEM. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney-U tests with Bonferroni-correction (p < 0.05). SnF2 showed a significant erosion protection. AF, SnF2, and SnCl2 were most anti-adherent. SnF2 and SnCl2 caused a pronounced basal pellicle with stannous precipitates. Compared to other fluoride monosubstances, stannous ions offer greater protection against erosive acidic attacks. Stannous ions act as crucial co-factor in this process.


Asunto(s)
Fluoruros , Erosión de los Dientes , Animales , Bovinos , Humanos , Fluoruros/farmacología , Erosión de los Dientes/prevención & control , Compuestos de Estaño , Fluoruro de Sodio/farmacología , Fluoruro de Sodio/química , Concentración de Iones de Hidrógeno
7.
Genet Mol Res ; 12(3): 3983-91, 2013 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-23479153

RESUMEN

We evaluated the response of individuals with metabolic syndrome to lifestyle modification intervention and examined the influence of the 48867A>C (Asp358Ala) IL6R (rs2228145) polymorphism on this response. Participants were randomly divided into two groups: NI, nutritional intervention; NIE, nutritional intervention and exercise practice. Intervention lasted three months and participants completed a comprehensive evaluation and had blood collected for biochemical measurements. Eighty-two sedentary individuals with at least three criteria for metabolic syndrome were included. Comparing metabolic syndrome parameters before and after intervention, a reduction of waist circumference was observed, although significant only for AA and AC genotypes. Also, a decrease in triglyceride levels was observed (significant for AA genotype individuals; for the AC genotype, only in the NIE group). Significant reduction of fasting glucose level was observed in all AA genotype individuals; for the AC genotype, only in the NI group. Systolic blood pressure showed significant reduction in AA and AC genotype individuals. After three months of lifestyle modification intervention, improvement in some of the metabolic syndrome parameters was observed, some associated with the IL6R genotype. At enrollment, participants with genotypes AA and AC showed more severe conditions regarding metabolic syndrome inclusion criteria, supporting previous reports that the A allele is a genetic risk factor. These individuals, however, had a better response to intervention compared to individuals with the CC genotype, suggesting that nutritional control and exercise practice could prevent risks associated with metabolic syndrome more efficiently in individuals bearing the A allele.


Asunto(s)
Síndrome Metabólico/terapia , Polimorfismo de Nucleótido Simple , Receptores de Interleucina-6/genética , Adulto , Alelos , Glucemia/metabolismo , Presión Sanguínea/genética , Brasil , HDL-Colesterol/sangre , Femenino , Estudios de Seguimiento , Frecuencia de los Genes , Genotipo , Humanos , Estilo de Vida , Masculino , Síndrome Metabólico/genética , Persona de Mediana Edad , Receptores de Interleucina-6/metabolismo , Triglicéridos/sangre , Circunferencia de la Cintura
8.
Phys Rev Lett ; 108(5): 057002, 2012 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-22400953

RESUMEN

We report the characterization of a two-qubit processor implemented with two capacitively coupled tunable superconducting qubits of the transmon type, each qubit having its own nondestructive single-shot readout. The fixed capacitive coupling yields the sqrt[iSWAP] two-qubit gate for a suitable interaction time. We reconstruct by state tomography the coherent dynamics of the two-bit register as a function of the interaction time, observe a violation of the Bell inequality by 22 standard deviations after correcting readout errors, and measure by quantum process tomography a gate fidelity of 90%.

9.
Eur Phys J E Soft Matter ; 35(4): 9708, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22534979

RESUMEN

We produce cellular material based on the formulation of model emulsions whose drop size and composition may be continuously tuned. The obtained solid foams are characterized by narrow cell and pore size distributions in direct relation with the emulsion structure. The mechanical properties are examined, by varying independently the cell size and the foam density, and compared to theoretical predictions. Surprisingly, at constant density, Young's modulus depends on the cell size. We believe that this observation results from the heterogeneous nature of the solid material constituting the cell walls and propose a mean-field approach that allows describing the experimental data. We discuss the possible origin of the heterogeneity and suggest that the presence of an excess of surfactant close to the interface results in a softer polymer layer near the surface and a harder layer in the bulk.


Asunto(s)
Emulsiones/química , Modelos Químicos , Polímeros/química , Tensoactivos/química , Simulación por Computador , Módulo de Elasticidad , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Propiedades de Superficie
10.
Nat Nanotechnol ; 17(10): 1072-1077, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36138200

RESUMEN

Semiconductor spin qubits based on spin-orbit states are responsive to electric field excitations, allowing for practical, fast and potentially scalable qubit control. Spin electric susceptibility, however, renders these qubits generally vulnerable to electrical noise, which limits their coherence time. Here we report on a spin-orbit qubit consisting of a single hole electrostatically confined in a natural silicon metal-oxide-semiconductor device. By varying the magnetic field orientation, we reveal the existence of operation sweet spots where the impact of charge noise is minimized while preserving an efficient electric-dipole spin control. We correspondingly observe an extension of the Hahn-echo coherence time up to 88 µs, exceeding by an order of magnitude existing values reported for hole spin qubits, and approaching the state-of-the-art for electron spin qubits with synthetic spin-orbit coupling in isotopically purified silicon. Our finding enhances the prospects of silicon-based hole spin qubits for scalable quantum information processing.

11.
Phys Rev Lett ; 107(25): 256804, 2011 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-22243102

RESUMEN

We demonstrate a hybrid architecture consisting of a quantum dot circuit coupled to a single mode of the electromagnetic field. We use single wall carbon nanotube based circuits inserted in superconducting microwave cavities. By probing the nanotube dot using a dispersive readout in the Coulomb blockade and the Kondo regime, we determine an electron-photon coupling strength which should enable circuit QED experiments with more complex quantum dot circuits.

12.
Sci Rep ; 11(1): 3008, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33542341

RESUMEN

Inflammatory cardiomyopathy diagnosed by endomyocardial biopsy (EMB) is common in non-ischemic heart failure (HF) and might be associated with adverse outcome. We aimed to identify markers predicting myocardial inflammation in HF. We screened 517 patients with symptomatic non-ischemic HF who underwent EMB; 397 patients (median age 54 [IQR 43/64], 28.7% females) were included in this study. 230 patients were diagnosed with myocardial inflammation, defined as ≥ 7.0 CD3+ lymphocytes/mm2 and/or ≥ 35.0 Mac1 macrophages/mm2 and were compared to 167 inflammation negative patients. Patients with myocardial inflammation were more often smokers (52.4% vs. 39.8%, p = 0.013) and had higher C-reactive protein (CRP) levels (5.4 mg/dl vs. 3.7 mg/dl, p = 0.003). In logistic regression models CRP ≥ 8.15 mg/dl (OR 1.985 [95%CI 1.160-3.397]; p = 0.012) and Troponin I (TnI) ≥ 136.5 pg/ml (OR 3.011 [1.215-7.464]; p = 0.017) were independently associated with myocardial inflammation, whereas no association was found for elevated brain natriuretic peptide (OR 1.811 [0.873-3.757]; p = 0.111). In prognostic performance calculation the highest positive predictive value (90%) was detected for the combination of Global longitudinal strain (GLS) ≥ -13.95% and TnI ≥ 136.5 pg/ml (0.90 (0.74-0.96)). Elevated CRP, TnI and GLS in combination with TnI can be useful to detect myocardial inflammation. Smoking seems to predispose for myocardial inflammation.


Asunto(s)
Proteína C-Reactiva/genética , Glutaminasa/sangre , Insuficiencia Cardíaca/sangre , Inflamación/sangre , Troponina I/sangre , Adulto , Biomarcadores/sangre , Femenino , Predisposición Genética a la Enfermedad , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/patología , Humanos , Inflamación/genética , Inflamación/patología , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/genética , Infarto del Miocardio/patología , Miocardio/metabolismo , Miocardio/patología , Valor Predictivo de las Pruebas , Pronóstico , Medición de Riesgo , Fumar/efectos adversos , Troponina I/genética
13.
Br J Dermatol ; 162(1): 64-73, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19712116

RESUMEN

Background Lupus erythematosus tumidus (LET) is a rare disease which was first described in 1909 but has not always been considered as a separate entity of cutaneous lupus erythematosus (CLE) in the international literature. Objectives To compare characteristic features of different subtypes of CLE and to analyse whether LET can be distinguished as a separate entity in the classification system of the disease. Methods The study involved 44 patients with CLE, including 24 patients with LET, 12 with discoid lupus erythematosus (DLE) and eight with subacute CLE (SCLE), from two centres in Germany. A core set questionnaire and an SPSS database were designed to enable a consistent statistical analysis. Results Location of skin lesions did not differ significantly between the CLE subtypes; however, the activity score was significantly lower in LET than in DLE (P < 0.01), and the damage score was significantly lower in LET than in SCLE (P < 0.01) and DLE (P < 0.01). Photosensitivity and antinuclear antibodies were confirmed to be different in LET compared with SCLE and DLE but without statistical significance. Moreover, histological analysis of skin biopsy specimens showed that abundant mucin deposition is significantly more present in LET compared with SCLE (P < 0.01) and DLE (P < 0.01) while prominent interface dermatitis and alteration of hair follicles were absent in LET. Conclusions Several significant differences were found between LET and other subtypes of CLE with regard to clinical, histological and laboratory parameters. These data strongly indicate that LET should be defined as a separate entity in the classification of CLE.


Asunto(s)
Lupus Eritematoso Cutáneo/clasificación , Adulto , Edad de Inicio , Anciano , Anticuerpos Antinucleares/análisis , Femenino , Alemania , Humanos , Lupus Eritematoso Cutáneo/inmunología , Lupus Eritematoso Cutáneo/patología , Lupus Eritematoso Discoide/clasificación , Lupus Eritematoso Discoide/inmunología , Lupus Eritematoso Discoide/patología , Masculino , Persona de Mediana Edad , Mucinas/análisis , Trastornos por Fotosensibilidad/etiología , Adulto Joven
14.
Eur Surg Res ; 45(3-4): 350-5, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21099224

RESUMEN

BACKGROUND: Since the rate of histologically 'negative' appendices still ranges between 15 and 20%, appendicitis in 'borderline' cases remains a challenging disease. As previously described, cell adhesion molecule expression correlates with different stages of appendicitis. Therefore, it was of interest to determine whether the 'negative' appendix correlated with the absence of E-selectin or vascular cell adhesion molecule-1 (VCAM-1). METHODS: Nineteen grossly normal appendices from a series of 120 appendectomy specimens from patients with suspected appendicitis were analysed in frozen sections for the expression of E-selectin and VCAM-1. As control, 5 normal appendices were stained. RESULTS: This study showed a coexpression of E-selectin and VCAM-1 in endothelial cells in early and recurrent appendicitis. In patients with symptoms for less than 6 h, only E-selectin was detected. Cases with fibrosis and luminal obliteration were only positive for VCAM-1. In cases of early appendicitis with symptoms of less than 6 h duration, a discordance between histological and immunohistochemical results was found. CONCLUSIONS: This report indicates that E-selectin and VCAM-1 expression could be useful parameters in the diagnosis of appendicitis in borderline cases.


Asunto(s)
Apendicitis/diagnóstico , Apendicitis/metabolismo , Selectina E/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismo , Apendicectomía , Apendicitis/patología , Apendicitis/cirugía , Apéndice/metabolismo , Apéndice/patología , Estudios de Casos y Controles , Células Endoteliales/metabolismo , Células Endoteliales/patología , Secciones por Congelación , Inmunohistoquímica , Proyectos Piloto , Recurrencia , Estudios Retrospectivos , Factores de Tiempo
15.
Carbohydr Polym ; 243: 116411, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32532384

RESUMEN

Porous materials were produced based on high internal phase emulsions (HIPE) formulation stabilized by modified cellulose nanocrystals (CNCs). CNCs were first modified with bromoisobutyryl bromide and used as Pickering emulsion stabilizers to formulate highly concentrated inverse emulsions. Solid foams with an open porosity were successively produced by free radical polymerization of styrene/divinylbenzene continuous phase. The final materials were characterized regarding their cell size distribution, porosity and mechanical properties and then compared with well-known styrene/DVB polyHIPE stabilized either with usual surfactants or solid particles.

16.
Oper Dent ; 45(6): E289-E307, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-33215202

RESUMEN

CLINICAL RELEVANCE: Bleaching performed at home while under the supervision of a dentist provides greater color alteration compared with whitening strips when evaluated with a spectrophotometer, although the color alteration was undetectable by unaided human eyes. SUMMARY: Objective: A systematic review and meta-analysis were performed to answer the following research question: Does the use of whitening strips (WS) lead to an equivalent color change compared with supervised dental bleaching in patients with permanent dentition?Methods: A search was performed on August 10, 2017 (updated on March 22, 2019), in PubMed, the Brazilian Library in Dentistry, Latin American and Caribbean Health Sciences Literature database, Cochrane Library, Scopus, Web of Science, and SIGLE, without restrictions regarding date or language. Abstracts from the International Association for Dental Research, unpublished and ongoing trial registries, dissertations, and theses were also searched. Only randomized clinical trials (parallel or split mouth) in patients with permanent dentition that compared WS with dentist-supervised dental bleaching performed at home (AH) or in office (IO) were included. The risk of bias (RoB) was evaluated using the Cochrane Collaboration tool. A meta-analysis with subgroup analysis (low and high peroxide concentration) was conducted for color change ΔE* (spectrophotometer) and ΔSGU (shade guide units), risk and intensity of tooth sensitivity (TS), gingival irritation (GI), and patient satisfaction using a random effects model. Heterogeneity was assessed with the Cochrane Q test and I2 statistics. GRADE (Grading of Recommendations, Assessment, Development and Evaluation) was used to assess the quality of the evidence.Results: After the removal of duplicates, followed by title and abstract screening, 20 studies remained. Only two studies were considered to have a low RoB; 11 had a high RoB, and seven had an unclear RoB. For WS versus IO, data were not available for the meta-analysis. For WS versus AH bleaching, a significant difference in ΔE* favoring the AH group was observed (standardized mean difference [SMD] = -0.50, 95% confidence interval [CI] -0.79 to 0.21), but the risk (risk ratio = 0.78, 95% CI 0.65 to 0.93) and intensity of TS (SMD = -0.30, 95% CI -0.56 to -0.04) were lower in the WS group. Color change in ΔSGU, risk and intensity of GI, and patient satisfaction were not significantly different between groups (p>0.20). The quality of evidence for ΔE*, risk and intensity of TS, and intensity of GI were graded as moderate.Conclusion: Although the risk and intensity of TS were lower in the WS group, dentist-supervised at-home bleaching led to a better color change when measured with a spectrophotometer, although the color alteration was undetectable by unaided human eyes.


Asunto(s)
Sensibilidad de la Dentina , Blanqueadores Dentales , Blanqueamiento de Dientes , Brasil , Sensibilidad de la Dentina/inducido químicamente , Humanos , Peróxido de Hidrógeno/uso terapéutico , Peróxidos , Blanqueadores Dentales/uso terapéutico
17.
Genet Mol Res ; 7(4): 1259-66, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19065761

RESUMEN

Orthodontic appliances are usually made of stainless steel, which contains metals such as nickel, chromium and iron that have been associated with DNA damage. The aim of the present study was to determine the genetic toxicity associated with orthodontic fixed appliances in twenty healthy patients (16 +/- 2.5 years) undergoing orthodontic treatment (fixed appliances - basic composition: stainless steel alloy), using the micronucleus (MN) and comet (CA) assays in buccal cells. Primary DNA damage level, as assessed by the CA, was low either before the beginning (1.5 +/- 1.05 damage index - DI) or 10 days after the placement of the orthodontic appliance (2.5 +/- 3.08 DI) and did not change significantly between these time points (p= 0.0913). Conversely, there was a significant increase in MN frequency 30 days after the beginning of the treatment (p= 0.0236). In this study, the MN assay was shown to be more sensitive than the CA. Other investigations are necessary in order to assess the genotoxic potential of orthodontic fixed appliances associated with long-term studies concerning these effects in orthodontic patients.


Asunto(s)
Metales Pesados/toxicidad , Mutágenos/toxicidad , Aparatos Ortodóncicos/efectos adversos , Adolescente , Cromo/análisis , Cromo/toxicidad , Ensayo Cometa , Daño del ADN , Femenino , Humanos , Hierro/análisis , Hierro/toxicidad , Masculino , Metales Pesados/análisis , Pruebas de Micronúcleos , Mucosa Bucal/efectos de los fármacos , Mucosa Bucal/patología , Pruebas de Mutagenicidad , Mutágenos/análisis , Níquel/análisis , Níquel/toxicidad
18.
RSC Adv ; 8(10): 5586-5595, 2018 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-35542449

RESUMEN

Polymeric nanocarriers are promising entities for cancer diagnosis and therapy. The aim of such nanocarriers is to selectively accumulate in cancerous tissue that is difficult to visualize or treat. The passive accumulation of a nanocarrier in a tumor through extravasation is often attributed to the enhanced permeation and retention (EPR) effect and the size and shape of the nanocarrier. However, the tumor microenvironment is very heterogeneous and the intratumoral pressure is usually high, leading to different opinions about how the EPR of nanocarriers through the irregular vasculature of a tumor leads to accumulation. In order to investigate this topic, we studied methods for the determination of pharmacokinetic parameters, biodistribution and the tumor uptake of nanocarriers. More specifically, we used non-invasive quantitative Single-Photon Emission Computed Tomography/Computed Tomography (qSPECT/CT) imaging of hyperbranched polyglycerols (HPGs) to explore the specific biodistribution and tumor uptake of six model nanocarriers in Rag2m mice. We were interested to see if a distinct molecular weight (MW) of nanocarriers (HPG 25, 50, 100, 200, 300, 500 kDa) is favoured by the tumor. To trace the model nanocarriers, HPGs were covalently linked to the strong chelator desferrioxamine (DFO), and radiolabeled with the gamma emitter 67Ga (EC = 100%, E γ = 185 keV (21.4%), 300 keV (16.6%), half-life = 3.26 d). Without the need for blood collection, but instead using qSPECT/CT imaging inside the heart, the blood circulation half-lives of the 67Ga labeled HPGs were determined and increased from 9.9 ± 2.9 to 47.8 ± 7.9 hours with increasing polymer MW. Total tumor accumulation correlated positively with the circulation time of the HPGs. Comparing the tumor-to-blood ratio dynamically revealed how blood and tumor concentrations of the nanocarrier change over time and when equilibrium is reached. The time of equilibrium is size-dependent and increases with molecular weight. Furthermore, the data indicate that for larger MWs, nanocarrier uptake and retention by the tumor is size independent. Further studies are necessary to advance our understanding of the interplay between MW and nanoparticle accumulation in tumors.

19.
J Hand Surg Eur Vol ; 40(7): 700-4, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25588666

RESUMEN

UNLABELLED: Surgical adhesives are useful supplements in surgery, but their benefit in tendon repair is uncertain. The purpose of this study was to evaluate the effect of BioGlue™ on strength of flexor tendon repair. A total of 60 porcine flexor tendons were divided into three groups. In group one, a conventional core and peripheral suture repair was used. In group two, a core suture and BioGlue™ were used. In group three, a conventional core and peripheral suture repair and BioGlue™ were used. We performed static and cyclic axial load testing and measured diameter of the repair site. We found that BioGlue™ did not improve the tensile strength when added to a core and peripheral suture and that there was an increase in bulk at the repair site. We conclude that BioGlue™ application cannot replace a peripheral suture as tensile strength significantly decreases without a peripheral suture, and it does not benefit a tendon already repaired with a core and peripheral suture. LEVEL OF EVIDENCE: n/a.


Asunto(s)
Proteínas , Traumatismos de los Tendones/cirugía , Tendones/cirugía , Resistencia a la Tracción , Adhesivos Tisulares , Animales , Modelos Animales , Técnicas de Sutura , Porcinos
20.
J Phys Condens Matter ; 24(45): 455901, 2012 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-23060596

RESUMEN

Bismuth sodium titanate (Bi(0.5)Na(0.5))TiO(3) (BNT) is considered to be one of the most promising lead-free alternatives to piezoelectric lead zirconate titanate (PZT). However, the effect of dopants on the material has so far received little attention from an atomic point of view. In this study we investigated the effects of cobalt-doping on the formation of additional phases and determined the preferred lattice site of cobalt in BNT. The latter was achieved by comparing the measured x-ray absorption near-edge structure (XANES) spectra to numerically calculated spectra of cobalt on various lattice sites in BNT. (Bi(0.5)Na(0.5))TiO(3) + x mol% Co (x = 0.0, 0.5, 1.0, 2.6) was synthesized via solid state reaction. As revealed by SEM backscattering images, a secondary phase formed in all doped specimens. Using both XRD and SEM-EDX, it was identified as Co(2)TiO(4) for dopant levels >0.5 mol%. In addition, a certain amount of cobalt was incorporated into BNT, as shown by electron probe microanalysis. This amount increased with increasing dopant levels, suggesting that an equilibrium forms together with the secondary phase. The XANES experiments revealed that cobalt occupies the octahedral B-site in the BNT perovskite lattice, substituting Ti and promoting the formation of oxygen vacancies in the material.

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