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621.
622.
Mesenchymal stem cells (MSC) are known for their vascular regeneration capacity by neoangiogenesis. Even though, several delivery approaches exist, particularly in the case of intravascular delivery, only limited number of cells reach the targeted tissue and are not able to remain on site. Applicated cells exhibit poor survival accompanied with a loss of functionality. Moreover, cell application techniques lead to cell death and impede the overall MSC function and survival. 3D cell spheroids mimic the physiological microenvironment, thus, overcoming these limitations. Therefore, in this study we aimed to evaluate and assess the feasibility of 3D MSCs spheroids for endovascular application, for treatment of ischemic peripheral vascular pathologies. Multicellular 3D MSC spheroids were generated at different cell seeding densities, labelled with ultra-small particles of iron oxide (USPIO) and investigated in vitro in terms of morphology, size distribution, mechanical stability as well as ex vivo with magnetic resonance imaging (MRI) to assess their trackability and distribution. Generated 3D spheroids were stable, viable, maintained stem cell phenotype and were easily trackable and visualized via MRI. MSC 3D spheroids are suitable candidates for endovascular delivery approaches in the context of ischemic peripheral vascular pathologies.  相似文献   
623.
Background. EarlyNutrition (www.project-earlynutrition.eu) is an international research project investigating the effects of early nutrition on metabolic programming.

Objective. To summarize, by performing a systematic review, current standards, recommendations, guidelines, and regulations (hereafter, referred to as documents) on the nutrition of children up to three years of age. Special emphasis was placed on long-term effects of early nutrition, such as the risk of cardiovascular disease, hypertension, overweight, obesity, metabolic syndrome, diabetes, or glucose intolerance.

Methods. MEDLINE, selected databases, and websites were searched for documents published between 2008 and January 2013.

Results. Forty two documents met the inclusion criteria. The strongest and most consistent evidence for a protective, long-term effect was documented for breastfeeding. Also, limiting the intake of sodium and rapidly absorbed carbohydrates, use of a specific meal pattern, reducing the consumption of saturated fatty acids by replacing them with polyunsaturated fatty acids, and lowering the intake of trans fatty acids, seems beneficial. Many documents did not evaluate long-term outcomes of interest to us, or reported insufficient or imprecise data. Inconsistency in recommendations for some outcomes and research gaps were identified.

Conclusions. Our findings may serve as a helpful tool in planning further research, preventive actions against important diet-related diseases, and guidelines improvement.  相似文献   

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The aim of this study as a part of the food traceability project “TRACE” funded by the EU was to investigate if honeys produced in regions with different climatic and geological characteristics could be discriminated on the basis of the isotopic data. The hydrogen, carbon, nitrogen and sulphur stable isotope ratios of 516 authentic honeys from 20 European regions are presented and discussed. As honey contains only small quantities of nitrogen and sulphur, the honey protein was precipitated in order to obtain measurable amounts of these elements. The mean hydrogen isotopic ratios of the honey protein were found to be significantly correlated with the mean hydrogen isotopic ratios of precipitation and groundwater in the production regions. Carbon isotopic ratios were influenced by climate. The sulphur stable isotope composition is clearly influenced by geographical location (sea spray effect) and surface geology of the production regions. The results show that the stable isotope ratios of the four bio-elements carbon, nitrogen, hydrogen and sulphur in honey protein can be applied to verify the origin of honey. Carbon and sulphur were identified by canonical discriminant analysis as providing the maximum discrimination between honey samples. For seven regions the percentage of correct classified samples is greater than 70%. It was concluded that the methodology in its current state can be used to provide reliable origin information.  相似文献   
627.
Radiation of tumor cells can lead to the selection and outgrowth of tumor escape variants. As radioresistant tumor cells are still sensitive to retargeting of T cells, it appears promising to combine radio- with immunotherapy keeping in mind that the radiation of tumors favors the local conditions for immunotherapy. However, radiation of solid tumors will not only hit the tumor cells but also the infiltrated immune cells. Therefore, we wanted to learn how radiation influences the functionality of T cells with respect to retargeting to tumor cells via a conventional bispecific T cell engager (BiTE) and our previously described modular BiTE format UNImAb. T cells were irradiated between 2 and 50 Gy. Low dose radiation of T cells up to about 20 Gy caused an increased release of the cytokines IL-2, TNF and interferon-γ and an improved capability to kill target cells. Although radiation with 50 Gy strongly reduced the function of the T cells, it did not completely abrogate the functionality of the T cells.  相似文献   
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629.
Background: Neuronal ischemia-reperfusion injury (IRI), such as it can occur in glaucoma or strokes, is associated with neuronal cell death and irreversible loss of function of the affected tissue. Hydrogen sulfide (H2S) is considered a potentially neuroprotective substance, but the most effective route of application and the underlying mechanism remain to be determined. Methods: Ischemia-reperfusion injury was induced in rats by a temporary increase in intraocular pressure (1 h). H2S was then applied by inhalation (80 ppm at 0, 1.5, and 3 h after reperfusion) or by intravenous administration of the slow-releasing H2S donor GYY 4137. After 24 h, the retinas were harvested for Western blotting, qPCR, and immunohistochemical staining. Retinal ganglion cell survival was evaluated 7 days after ischemia. Results: Both inhalative and intravenously delivered H2S reduced retinal ganglion cell death with a better result from inhalative application. H2S inhalation for 1.5 h, as well as GYY 4137 treatment, increased p38 phosphorylation. Both forms of application enhanced the extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation, and inhalation showed a significant increase at all three time points. H2S treatment also reduced apoptotic and inflammatory markers, such as caspase-3, intracellular adhesion molecule 1 (ICAM-1), vascular endothelial growth factor (VEGF), and inducible nitric oxide synthase (iNOS). The protective effect of H2S was partly abolished by the ERK1/2 inhibitor PD98059. Inhalative H2S also reduced the heat shock response including heme oxygenase (HO-1) and heat shock protein 70 (HSP-70) and the expression of radical scavengers such as superoxide dismutases (SOD1, SOD2) and catalase. Conclusion: Hydrogen sulfide acts, at least in part, via the mitogen-activated protein kinase (MAPK) ERK1/2 to reduce apoptosis and inflammation. Both inhalative H2S and intravenous GYY 4137 administrations can improve neuronal cell survival.  相似文献   
630.
Biomaterials such as seashells are intriguing due to their remarkable properties, including their hierarchical structure from the nanometer to the micro- or even macroscopic scale. Transferring this nanostructure to generate nanostructured polymers can improve their electrical conductivity. Here, we present the synthesis of polypyrrole using waste seashell powder as a template to prepare a polypyrrole/CaCO3 composite material. Various synthesis parameters were optimized to produce a composite material with an electrical conductivity of 2.1 × 10−4 ± 3.2 × 10−5 S/cm. This work presents the transformation of waste seashells into sustainable, electronically conductive materials and their application as an antistatic agent in polymers. The requirements of an antistatic material were met for a safety shoe sole.  相似文献   
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