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Cellulose nanocrystals (CNCs) are promising bio-derived nanomaterials for the bottom-up fabrication of biomedical constructs. In this report, dicarboxylic acid-functionalized CNC ...(DCC) was functionalized with arginylglycylaspartic acid (RGD) tripeptide as a motif for improved cell adhesion and targeting. The product (DCC-RGD) self-assembled into a more elongated nanofibrillar structure through lateral and end-to-end association. When added into poly(ethylene imine) (PEI)/pDNA polyplex solution, nanocelluloses interacted electrostatically with positively charged polyplexes without affecting their integrity. The constructs were tested for their potentials as non-viral transfection reagents. Cell viability and transfection efficiency of fibroblast NIH3T3 cells were monitored as a function of CNC concentration where, in general, viability increased as the CNC concentration increased, and transfection efficiency could be optimized. Using wild-type MDCK and αV-knockout MDCK cells, the construct was able to provide targeted uptake of polyplexes. The findings have potential applications, for example, cell-selective in vitro or ex vivo transfection of autologous mesenchymal stem cells for cell therapy, or bottom-up design of future innovative biomaterials.
We determine the reliability function of the exponential-server timing channel (ESTC) in the limit as the data rate approaches zero. The limit shows that at low rates, the ESTC is strictly more ...reliable than the Poisson channel without dark current, answering a question Arikan posed in these Transactions. The proof employs a distance metric over inputs to timing channels that parallels Euclidean and Hamming distance for conventional channels. A consequence of the proof is that bounded-distance decoding, with distance measured according to this metric, is exponentially optimum for the ESTC in the low-rate regime. We also prove the straight-line bound for the channel and a bound on the reliability of timing channels with general service distributions in the limit as the data rate approaches zero.
Results of the FUEL Trial Goldberg, David J; Zak, Victor; Goldstein, Bryan H ...
Circulation (New York, N.Y.),
2020-February-25, 2020-02-25, Letnik:
141, Številka:
8
Journal Article
Recenzirano
Odprti dostop
BACKGROUND:The Fontan operation creates a total cavopulmonary connection, a circulation in which the importance of pulmonary vascular resistance is magnified. Over time, this circulation leads to ...deterioration of cardiovascular efficiency associated with a decline in exercise performance. Rigorous clinical trials aimed at improving physiology and guiding pharmacotherapy are lacking.
METHODS:The FUEL trial (Fontan Udenafil Exercise Longitudinal) was a phase III clinical trial conducted at 30 centers. Participants were randomly assigned udenafil, 87.5 mg twice daily, or placebo in a 1:1 ratio. The primary outcome was the between-group difference in change in oxygen consumption at peak exercise. Secondary outcomes included between-group differences in changes in submaximal exercise at the ventilatory anaerobic threshold, the myocardial performance index, the natural log of the reactive hyperemia index, and serum brain-type natriuretic peptide.
RESULTS:Between 2017 and 2019, 30 clinical sites in North America and the Republic of Korea randomly assigned 400 participants with Fontan physiology. The mean age at randomization was 15.5±2 years; 60% of participants were male, and 81% were white. All 400 participants were included in the primary analysis with imputation of the 26-week end point for 21 participants with missing data (11 randomly assigned to udenafil and 10 to placebo). Among randomly assigned participants, peak oxygen consumption increased by 44±245 mL/min (2.8%) in the udenafil group and declined by 3.7±228 mL/min (–0.2%) in the placebo group (P=0.071). Analysis at ventilatory anaerobic threshold demonstrated improvements in the udenafil group versus the placebo group in oxygen consumption (+33±185 3.2% versus –9±193 –0.9% mL/min, P=0.012), ventilatory equivalents of carbon dioxide (–0.8 versus –0.06, P=0.014), and work rate (+3.8 versus +0.34 W, P=0.021). There was no difference in change of myocardial performance index, the natural log of the reactive hyperemia index, or serum brain-type natriuretic peptide level.
CONCLUSIONS:In the FUEL trial, treatment with udenafil (87.5 mg twice daily) was not associated with an improvement in oxygen consumption at peak exercise but was associated with improvements in multiple measures of exercise performance at the ventilatory anaerobic threshold.
CLINICAL TRIAL REGISTRATION:URLhttps://www.clinicaltrials.gov. Unique identifierNCT02741115.
Loss of integrity in nonlesional white matter occurs as a fundamental feature of multiple sclerosis in adults. The purpose of our study was to evaluate DTI-derived measures of white matter ...microstructure in children with MS compared with age- and sex-matched controls by using tract-based spatial statistics.
Fourteen consecutive pediatric patients with MS (11 female/3 male; mean age, 15.1 ± 1.6 years; age range, 12-17 years) and age- and sex-matched healthy subjects (11 female/3 male; mean age, 14.8 ± 1.7 years) were included in the study. After we obtained DTI sequences, data processing was performed by using tract-based spatial statistics.
Compared with healthy age- and sex-matched controls, children with multiple sclerosis showed a global decrease in mean fractional anisotropy (P ≤ .001), with a concomitant increase in mean (P < .001), radial (P < .05), and axial diffusivity (P < .001). The most pronounced fractional anisotropy value decrease in patients with MS was found in the splenium of the corpus callosum (P < .001). An additional decrease in fractional anisotropy was identified in the right temporal and right and left parietal regions (P < .001). Fractional anisotropy of the white matter skeleton was related to disease duration and may, therefore, serve as a diagnostic marker.
The microstructure of white matter is altered early in the disease course in childhood multiple sclerosis.
Purpose: There are reports of greater survival rates in nonsmall cell lung cancer (NSCLC) patients of female gender. The objective of this study was to evaluate the role of gender in survival of ...NSCLC patients treated surgically with curative intent (stage I/II).
Methods: In a retrospective cohort design, we screened 498 NSCLC patients submitted to thoracotomies at the hospital Sγo Lucas, in Porto Alegre, Brazil from 1990 to 2009. After exclusion of patients that did not fit to all the inclusion criteria, we analyzed survival rates of 385 subjects. Survival was analyzed using the Kaplan-Meier method. The Cox regression model was used to evaluate potential confounding factors.
Results: Survival rates at 5 and 10 years were 65.3% and 49.5% for women and 46.5% and 33.2% for men, respectively ( P = 0.006). Considering only stage I patients, the survival rates at 5 and 10 years were 76.2% and 55.1% for women and 50.7% and 35.4% for men, respectively ( P = 0.011). No significant differences in survival rates were found among stage II patients.
Conclusions: Our results show female gender as a possible protective factor for better survival of stage I NSCLC patients, but not among stage II patients. This study adds data to the knowledge that combined both genders survival rates for NSCLC is not an adequate prognosis.
The utility of auxetic materials in applications such as foams and composites is contingent upon the performance of these materials under cyclic loading. Recently, several textile materials (knitted, ...woven, and nonwoven fabrics) have been found to exhibit auxetic properties, either through design and/or the use of a postprocessing treatment. In the wake of these advancements, this research examines the reversibility of the out‐of‐plane auxetic response in previously studied polyester fiber needle‐punched nonwovens. Herein, a heat‐compressed nonwoven is strained cyclically to different levels, and the thickness is measured before and after straining. While axial extension is found to be elastic for up to 3% strain, thickness increases (auxetic responses) are almost completely reversible for 1% axial strain and highly reversible for 2% and 3% axial strain. Irreversible changes can be clearly observed starting at strains of 2% and larger, especially for a higher number of cycles. Combining these results with the previous understanding from microscopic and tomographic imaging, possible reversible (straightening of bent fibers and fiber bundles) and irreversible (slipping or breaking of fibers) structural deformations leading to thickness changes are identified. These processes influence the magnitude of the auxetic response within and beyond the elastic strain regime, respectively.
Reversibility of the out‐of‐plane auxetic response in polyester needle‐punched nonwovens is examined. Auxetic nonwovens are strained cyclically to different levels (n = 1, 2, 3, 5, 10 or 20% strain), and thickness is measured. It is found that average thickness changes are largely reversible for up to 3% strain. Reversible/irreversible structural changes are proposed to describe the behavior.
Raman scattering and polarization-dependent synchrotron radiation X-ray absorption, in combination, have been employed to examine the residual stress of undoped GaN epitaxial layers grown on Si by ...molecular beam epitaxy and Si-doped n-type GaN layers grown on sapphire by metalorganic chemical vapor deposition. Values of the lattice constant of different GaN films can be deduced from the interatomic distances in the second coordination shell around Ga by polarization-dependent extended X-ray absorption fine structure analysis and the strain of the films can be obtained. This result is further confirmed by Raman scattering spectra in which the phonon modes show a significant shift between different GaN epitaxial layers with different growth conditions.
Abstract
Purpose:
Radiology represents a highly relevant part of undergraduate medical education from preclinical studies to subinternship training. It is therefore important to establish a content ...base for teaching radiology in German Medical Faculties.
Materials and Methods:
The German Society of Radiology (DRG) developed a model curriculum for radiological teaching at German medical universities, which is presented in this article. There is also a European model curriculum for undergraduate teaching (U-level curriculum of the European Society of Radiology). In a modular concept, the students shall learn important radiological core principles in the realms of knowledge, skills and competences as well as core scientific competences in the imaging sciences.
Results:
The curriculum is divided into two modules. Module 1 includes principles of radiation biology, radiation protection and imaging technology, imaging anatomy as well as the risks and side effects of radiological methods, procedures and contrast media. This module is modality-oriented. Module 2 comprises radiological diagnostic decision-making and imaging-based interventional techniques for various disease entities. This module is organ system-oriented.
Conclusion:
The curriculum is meant as a living document to be amended and revised at regular intervals. The curriculum can be used as a basis for individual curricular development at German Medical Faculties. It can be integrated into traditional or reformed medical teaching curricula.
Key Points:
• Radiology is an integral and important part of medical education.
• The German Society of Radiology (DRG) developed a model curriculum for teaching radiology at German Medical Faculties to help students develop the ability to make medical decisions based on scientific knowledge and act accordingly.
• This curriculum can be used for individual curricular development at medical departments. It is divided into two modules with several chapters.
Citation Format:
• Ertl-Wagner B, Barkhausen J, Mahnken AH et al. White Paper: Radiological Curriculum for Undergraduate Medical Education in Germany. Fortschr Röntgenstr 2016; 188: 1017 – 1023
On-axis and vicinal GaN/AlN/6H-SiC structures grown under identical conditions have been studied by x-ray diffraction and transmission electron microscopy to demonstrate the distinctive features of ...vicinal surface epitaxy (VSE) of nitrides on SiC. In VSE, the epilayers are tilted from the substrate due to the out-of-plane lattice mismatch (Nagai tilts), and the in-plane mismatch strains are more relaxed. The majority of misfit dislocations (MDs) at the vicinal AlN/6H-SiC interface are found to be unpaired partial MDs that are geometrically necessary to correct the stacking sequences from 6H to 2H. This mechanism indicates that it is possible to develop "step-controlled-epitaxy" strategies to control strain relaxation by adjusting the substrate offcut angles.
Although clinical evidence of endotoxemia has been associated with the development of acute laminitis in hospitalized horses with gastrointestinal diseases and endotoxins have been detected in the ...circulation of horses with experimentally-induced laminitis, it is unclear what role, if any, endotoxins have play the pathogenesis of the disease. Therefore, in the present study we compared the effects of endotoxin infusion to that of intra-gastric administration of mixed carbohydrate (CHO) on clinical signs of laminitis, plasma concentrations of TNF-α and IL-10, and laminar tissue expression of 20 genes associated with inflammation. Horses were divided into 4 groups: Control (water placebo, n=7), endotoxin infusion (LPS, n=6), CHO/Developmental (30% decrease in central venous pressure, n=6) and CHO/Lame (Obel grade I laminitis, n=7). Horses in the LPS group developed clinical signs consistent with systemic inflammation, had rapid increases in plasma concentrations of both TNF-α and IL-10, and leukopenia, but did not have any changes in laminar tissue expression of the genes associated with inflammation. In contrast, horses administered CHO developed clinical signs consistent with systemic inflammation, had more delayed increases in TNF-α, IL-10 and total leukocyte counts, and had marked increases in laminar tissue expression of the genes associated with inflammation. Only the horses administered CHO developed clinical signs of laminitis, providing additional credence to the concept that factors other than endotoxin are responsible for the changes in laminar tissue gene expression that occur during the development of acute equine laminitis.
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