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1.
Am J Respir Crit Care Med ; 204(8): 943-953, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34283704

RESUMO

Rationale: Previous cross-sectional studies have demonstrated that chest magnetic resonance imaging (MRI) is sensitive to detect early lung disease in infants and preschool children with cystic fibrosis (CF) without radiation exposure. However, the ability of MRI to detect the progression of lung disease and the impact of early diagnosis in preschool children with CF remains unknown. Objectives: To investigate the potential of MRI to detect progression of early lung disease and impact of early diagnosis by CF newborn screening (NBS) in preschool children with CF. Methods: An annual MRI was performed from diagnosis over 4 years in a cohort of 96 preschool children with CF (age, 0-4 yr) who received concurrent diagnoses on the basis of NBS (n = 28) or clinical symptoms (n = 68). MRI scans were evaluated using a dedicated morphofunctional score, and the relationship between longitudinal MRI score and respiratory symptoms, pulmonary exacerbations, upper airway microbiology, and mode of diagnosis was determined. Measurements and Main Results: The MRI global score increased in the total cohort of children with CF during preschool years (P < 0.001) and was associated with cough, pulmonary exacerbations (P < 0.0001), and the detection of Staphylococcus aureus and Haemophilus influenzae (P < 0.05). MRI-defined abnormalities in lung morphology-especially airway wall thickening/bronchiectasis-were lower in children with CF diagnosed by NBS than in children with clinically diagnosed CF throughout the observation period (P < 0.01). Conclusions: MRI detected progression of early lung disease and benefits of early diagnosis by NBS in preschool children with CF. These findings support MRI as a sensitive outcome measure for diagnostic monitoring and early intervention trials in preschool children with CF. Clinical trial registered with www.clinicaltrials.gov (NCT02270476).


Assuntos
Fibrose Cística/diagnóstico por imagem , Imageamento por Ressonância Magnética , Triagem Neonatal , Pré-Escolar , Fibrose Cística/fisiopatologia , Progressão da Doença , Diagnóstico Precoce , Feminino , Humanos , Lactente , Recém-Nascido , Modelos Lineares , Estudos Longitudinais , Masculino , Estudos Prospectivos
2.
Langmuir ; 36(45): 13448-13456, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33151688

RESUMO

This study reports on the potential-induced charge and mass transfer between an ultrathin polypyrrole (PPy) film and an electrolyte by simultaneous in situ X-ray reflectivity (XRR) and electrochemistry (EC) utilizing their sensitivity to electrons. An about 30 nm thin PPy film was deposited on a silicon single crystal by fast potential cycling, providing a dense film of an extraordinary small surface roughness. XRR was recorded from the PPy film in an aqueous 0.1 M perchloric acid at electric potentials between -0.2 V and +0.5 V vs Ag/AgCl. The PPy film shows typical reversible and linear changes in film thickness and electron density arising from the potential-dependent electrolyte incorporation. By introducing EC-XRR, a comprehensive analysis combining in situ XRR and EC, the net number of electrons passing through the PPy-electrolyte interface was deduced along with the potential-induced thickness variations, indicating a complex exchange mechanism. Evidently, along with the anion transfer, parallel charge compensation by protons and a volume and electron compensating counterflow of solvent molecules take place. Complementary time-dependent EC-XRR scans indicate that these exchange mechanisms are individual in two potential ranges. The low actuation along with a high pseudocapacitance suggest the fast potentiodynamically deposited PPy film as a promising supercapacitor material.

3.
J Chem Phys ; 152(7): 074705, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32087665

RESUMO

We have investigated the surface structure of a curved ZnO-crystal, going from the (0001)-facet at 0° miscut to the (101¯4)-facet at a miscut of 24.8° using scanning tunneling microscopy and low energy electron diffraction. We find that the surface separates locally into (0001)-terraces and (101¯4)-facets, where the ratio between the facets depends on the miscut angle. In X-ray photoemission spectroscopy (XPS) the intensity of an O 1s component scaling with the step density of the surface is observed. No other facets were observed and the surface maintains a high degree of order over all angles. Such a curved ZnO crystal can be used for systematic studies relating the step density to the chemical reactivity using XPS to probe the curved surface at different positions.

4.
Front Oncol ; 9: 805, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31555582

RESUMO

Dendritic cell (DC)-based vaccines pulsed with high hydrostatic pressure (HHP)-inactivated tumor cells have been demonstrated to be a promising immunotherapy for solid tumors. We focused on sole injection of tumor cells that were inactivated by HHP and their combination with local radiotherapy (RTx) for in vivo induction of anti-tumor immune responses. HHP-treatment of tumor cells resulted in pre-dominantly necrotic cells with degraded DNA. We confirmed that treatments at 200 MPa or higher completely inhibited the formation of tumor cell colonies in vitro. No tumor growth was seen in vivo after injection of HHP-treated tumor cells. Single vaccination with HHP-killed tumor cells combined with local RTx significantly retarded tumor growth and improved the survival as shown in B16-F10 and CT26 tumor models. In B16-F10 tumors that were irradiated with 2 × 5Gy and vaccinated once with HHP-killed tumor cells, the amount of natural killer (NK) cells, monocytes/macrophages, CD4+ T cells and NKT cells was significantly increased, while the amount of B cells was significantly decreased. In both models, a trend of increased CD8+ T cell infiltration was observed. Generally, in irradiated tumors high amounts of CD4+ and CD8+ T cells expressing PD-1 were found. We conclude that HHP generates inactivated tumor cells that can be used as a tumor vaccine. Moreover, we show for the first time that tumor cell-based vaccine acts synergistically with RTx to significantly retard tumor growth by generating a favorable anti-tumor immune microenvironment.

5.
Phys Rev Lett ; 123(24): 246001, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31922849

RESUMO

Bimetallic catalysts can undergo segregation or redistribution of the metals driven by oxidizing and reducing environments. Bragg coherent diffraction imaging (BCDI) was used to relate displacement fields to compositional distributions in crystalline Pt-Rh alloy nanoparticles. Three-dimensional images of internal composition showed that the radial distribution of compositions reverses partially between the surface shell and the core when gas flow changes between O_{2} and H_{2}. Our observation suggests that the elemental segregation of nanoparticle catalysts should be highly active during heterogeneous catalysis and can be a controlling factor in synthesis of electrocatalysts. In addition, our study exemplifies applications of BCDI for in situ 3D imaging of internal equilibrium compositions in other bimetallic alloy nanoparticles.

6.
PLoS One ; 10(6): e0129104, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26121653

RESUMO

OBJECTIVE: Emergency cervical cerclage is one of the treatment options for the reduction of preterm birth. The aim of this study is to assess neonatal outcome after cerclage with special focus on adverse effects in very low birth weight infants. STUDY DESIGN: Retrospective cohort study. Classification of cerclages in history-indicated (HIC, n = 38), ultrasound-indicated (UIC, n = 29) and emergency/ physical examination-indicated (PEIC, n = 33) cerclage. Descriptive analysis of pregnancy and neonatal outcome (admission to NICU, duration of hospitalization, respiratory outcome (intubation, CPAP, FiO2max), neonatal complications (ROP, IVH)). Statistical comparison of perinatal parameters and outcome of neonates <1500 g after cerclage with a birth weight matched control group. RESULTS: Neonates <1500 g after PEIC show significantly impaired outcome, i.e. prolonged respiratory support (total ventilation in days, CPAP, FiO2max) and higher rates of neonatal complications (IVH ≥ II, ROP ≥ 2). Placental pathologic evaluation revealed a significantly higher rate of chorioamnionitis (CAM) after PEIC. Neonates <1500 g after UIC or HIC show no significant difference in neonatal complications or CAM. CONCLUSIONS: In our study PEIC is associated with adverse neonatal outcome in infants <1500 g. The high incidence of CAM indicates a potential inflammatory factor in the pathogenesis. Large well-designed RCTs are required to give conclusive answers to the question whether to prolong or to deliver.


Assuntos
Cerclagem Cervical , Tratamento de Emergência , Resultado da Gravidez , Adulto , Parto Obstétrico , Feminino , Humanos , Recém-Nascido , Gravidez
7.
J Plast Reconstr Aesthet Surg ; 68(5): 729-35, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25656337

RESUMO

PURPOSE: Aim of this study was to measure the outcome of hamstring transfer for quadriceps reconstruction after soft tissue sarcoma resection and to identify risk factors influencing postoperative results. METHODS: 43 patients underwent hamstring transfer after sarcoma resection. Medical records were reviewed for surgical technique and complications. Physical examination included assessment of range of motion and muscle strength as well as plantar pressure distribution by computerized dynamometer and podometry, respectively. Additionally, patients' satisfaction, quality of life and karnofsky index were assessed. RESULTS: Sole biceps transfer was performed in 31 (74%) and combined biceps/semitendinosus or gracilis transfer in 12 patients (26%). In 91%of cases 3/4 or more of the quadriceps muscle had to be removed. Postoperative complications occurred in 16 patients (37%). 17 patients (40%) were available for physical examination. Mean follow-up was 61 months (22-107). Average knee flexion was 74° (35-110°). All patients had full knee extension. Average extension force was 44% (19-79%) and flexion-force 74% (55-100%) of the unaffected leg. Mean plantar pressure distribution was 119% (44-200%) on the forefoot and 107% (60-169%) on the heel. Average patient satisfaction score was 16 (9-25), quality of life assessment was 78 (54-92) and Karnofsky Index was 82% (70-90%). Besides patient's age and the extent of resection, the surgical technique had statistically significant influence on functional outcome and postoperative complications (p < 0.05). CONCLUSION: Hamstring transfer is feasible for quadriceps reconstruction after massive tumor resection from the thigh. In contrast to biceps alone, combined semitendinosus or gracilis transfer revealed comparable outcome but higher complication rates.


Assuntos
Joelho/cirurgia , Músculo Esquelético/transplante , Músculo Quadríceps/cirurgia , Sarcoma/cirurgia , Transferência Tendinosa/métodos , Tendões/transplante , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Instabilidade Articular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Força Muscular , Satisfação do Paciente , Qualidade de Vida , Amplitude de Movimento Articular , Procedimentos de Cirurgia Plástica/métodos , Coxa da Perna/cirurgia , Resultado do Tratamento
8.
Angew Chem Int Ed Engl ; 53(4): 1062-6, 2014 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-24311464

RESUMO

The superior physical properties of carbon nanotubes (CNTs) have led to their broad application. Intrinsically, CNTs tend to agglomerate from hydrophobic interactions, which is highly undesirable for solution processing and device fabrication. Commonly, a stabilizer consisting of organic surfactants or polymers is used to disperse CNTs. Recently, we synthesized nitrogen-doped carbon hollow nanospheres (25-90 nm), termed carbon "nanobubbles". They bear superior dispersability in water and distinctive graphitic order. Herein, we describe the nanobubble-assisted dispersion of CNTs in aqueous solution upon sonication. This process relies on the π-π interaction between the two aromatic carbon nanostructures, which can process their carbon mixture in water into conductive filter membranes, ink, and discs. This stabilization can be extended to other aromatic carbons. In addition, the π-π interaction may create a new type of carbon p-n junction that can be used to improve charge separation.


Assuntos
Carbono/química , Nanoestruturas/química , Coloides/química , Nitrogênio/química , Tamanho da Partícula , Propriedades de Superfície
9.
Transpl Int ; 26(5): 545-51, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23383606

RESUMO

Transient elastography (TE, Fibroscan) has been established as a noninvasive assessment tool of liver fibrosis. We evaluated potentials and limitations of TE for identifying renal allograft fibrosis. The technical possibility of kidney examination by TE was assessed in two 10-week-old German landrace pigs and kidney stiffness (KS) was evaluated in 164 renal transplant patients. KS could be determined in all animals at the pole and pars media (29 ± 10 kPa vs. 31 ± 17 kPa). In human renal allografts KS was successfully performed in 94.5% of the test series with reliable results in 72% of the measurements. Mean KS at the pole or pars media were comparable (35.0 ± 19.9 kPa vs. 33.2 ± 18.6 kPa). Significantly higher KS was detected in renal allografts with histologically confirmed advanced fibrosis. Body-mass-index, skin-allograft distance, and peri or intrarenal fluid accumulation were important confounders of successful KS measurements (BMI: r = -0.31; P < 0.001; distance: r = -0.50; P < 0.001). Notably, KS did not correlate with renal function. TE represents a noninvasive approach in selected transplant recipients to identify allografts with severe fibrosis. The heterogeneous kidney morphology and several other confounding factors negatively affect measurability of KS by TE. Further technical modifications are required to improve applicability of TE for kidney assessment.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Transplante de Rim , Rim/patologia , Adulto , Animais , Creatinina/sangue , Técnicas de Imagem por Elasticidade/estatística & dados numéricos , Feminino , Fibrose , Humanos , Rim/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Sus scrofa , Transplante Homólogo
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