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1.
The influence of two peroxides (peroxydicarbonate/dilauroyl peroxide) with various concentrations (10–200 mmol/kg PP) and their effective opportunity to introduce long chain branched (LCB) were investigated. The dependence of a single and double extrusion step and the changes of the properties were studied. Experiments were carried out in a single screw extruder at 180°C for the first extrusion step (modification) and at 240°C for the second extrusion step (processing simulation). Melt flow rate and dynamic rheological properties were studied at a measuring temperature of 230°C. For the definitive determination of long chain branched polypropylene (LCB-PP) served the extensional rheology measurements. The mechanical properties were examined via tensile test and impact tensile test. Summarized, LCB (melt strength) could be observed via extensional rheology for all modified specimens and the mechanical properties were maintained or even improved for the modified samples. Particularly, samples containing dilauroyl peroxide display excellent mechanical properties in this study.  相似文献   
2.

1 Scope

During food processing, the Maillard reaction (МR) may occur, resulting in the formation of glycated proteins. Glycated proteins are of particular importance in food allergies because glycation may influence interactions with the immune system. This study compared native and extensively glycated milk allergen β‐lactoglobulin (BLG), in their interactions with cells crucially involved in allergy.

2 Methods and results

BLG was glycated in MR and characterized. Native and glycated BLG were tested in experiments of epithelial transport, uptake and degradation by DCs, T‐cell cytokine responses, and basophil cell degranulation using ELISA and flow cytometry. Glycation of BLG induced partial unfolding and reduced its intestinal epithelial transfer over a Caco‐2 monolayer. Uptake of glycated BLG by bone marrow–derived dendritic cells (BMDC) was increased, although both BLG forms entered BMDC via the same mechanism, receptor‐mediated endocytosis. Once inside the BMDC, glycated BLG was degraded faster, which might have led to observed lower cytokine production in BMDC/CD4+ T‐cells coculture. Finally, glycated BLG was less efficient in induction of degranulation of BLG‐specific IgE sensitized basophil cells.

3 Conclusions

This study suggests that glycation of BLG by MR significantly alters its fate in processes involved in immunogenicity and allergenicity, pointing out the importance of food processing in food allergy.  相似文献   
3.
The use of enzymes may improve the functional properties of various food ingredients. The aim of this study was to examine the effects of proteolytic contaminants in phenol oxidases on β-lactoglobulin (BLG). In the presence of Trametes versicolor laccase and Agaricus bisporus tyrosinase, both variants of BLG (A and B) underwent removal of a peptide from the N-terminus. The truncated forms were more susceptible to digestion by pepsin. The truncation of BLG resulted from contaminating proteases and not due to the action of phenol oxidases. The removal of N-terminal peptides proceeded quickly, while the rest of the globular protein remained resistant to proteolysis for up to 3 h. In the case of the application of enzymes in food bioprocessing, it may be important to carefully monitor the effects of contaminating proteases in enzyme preparations used.  相似文献   
4.
Electron densities in a plasma column may be estimated from measurements of phase shift in the radiation scattered at various angles.  相似文献   
5.
We report about the results on positioning of the ankle joint of a hemiplegic patient and of normal experimental subjects, using functional electrical stimulation (FES) of antagonistic muscle groups and position feedback. Such a controller is intended to be used as the execution level of a multilevel orthotic system. The synthesis of the controller has been made with the aid of the components of an analog hybrid computer. Experimental results show that the static and dynamic properties of regulated movements are not essentially inferior to the properties of voluntary movements. There are stated technological problems that will have to be solved before the controller can be clinically applied for rehabilitation purposes. At the present state of the art, the poor technology of FES, the unsolved problem of fatigue with FES muscles, size, price, and bad cosmetic effect prevent the position controller from being clinically applicable.  相似文献   
6.
β-Lactoglobulin (BLG) is an important nutrient of dairy products, but it represents a serious health risk in patients allergic to milk. Sour cherry (Prunus cerasus L.) extract (SCE) is frequently added as a natural food colour in composite foods, such as fruit yogurt, ice creams, frappés and milkshakes. The aim of this study was to investigate the potential of laccase to cross-link BLG in the presence of an SCE and to characterise the obtained products for their bioactivity.  相似文献   
7.
The still undiscovered fluid ferroelectric nematic phase is expected to exhibit a much faster and easier response to an external electric field compared to conventional ferroelectric smectic liquid crystals; therefore, the discovery of such a phase could open new avenues in electro‐optic device technology. Here, experimental evidence of a ferroelectric response to a switching electric field in a low molar mass nematic liquid crystal is reported and connected with field‐induced biaxiality. The fluid is made of bent‐core polar molecules and is nematic over a range of 120 °C. Combining repolarization current measurements, electro‐optical characterizations, X‐ray diffraction and computer simulations, ferroelectric switching is demonstrated and it is concluded that the response is due to field‐induced reorganization of polar cybotactic groups within the nematic phase. This work represents significant progress toward the realization of ferroelectric fluids that can be aligned at command with a simple electric field.  相似文献   
8.
We report an ultra-low-voltage RF receiver for applications in the 2.4 GHz band, designed in a 90 nm CMOS technology. The sliding-IF receiver prototype includes an LNA, an image-reject LC filter with single-ended to differential conversion, an RF mixer, an LC IF filter, a quadrature IF mixer, RF and IF LO buffers, and an I/Q baseband section with a VGA and a low-pass channel-select filter in each path, all integrated on-chip. It has a programmable overall gain of 30 dB, noise figure of 18 dB, out-of-channel IIP3 of -22 dBm. The 3.4 mm2 chip consumes 8.5 mW from a 0.5 V supply.  相似文献   
9.
The existence of a potential primary central nervous system lymphoma-specific genomic signature that differs from the systemic form of diffuse large B cell lymphoma (DLBCL) has been suggested, but is still controversial. We investigated 19 patients with primary DLBCL of central nervous system (DLBCL CNS) using the TruSeq Amplicon Cancer Panel (TSACP) for 48 cancer-related genes. Next generation sequencing (NGS) analyses have revealed that over 80% of potentially protein-changing mutations were located in eight genes (CTNNB1, PIK3CA, PTEN, ATM, KRAS, PTPN11, TP53 and JAK3), pointing to the potential role of these genes in lymphomagenesis. TP53 was the only gene harboring mutations in all 19 patients. In addition, the presence of mutated TP53 and ATM genes correlated with a higher total number of mutations in other analyzed genes. Furthermore, the presence of mutated ATM correlated with poorer event-free survival (EFS) (p = 0.036). The presence of the mutated SMO gene correlated with earlier disease relapse (p = 0.023), inferior event-free survival (p = 0.011) and overall survival (OS) (p = 0.017), while mutations in the PTEN gene were associated with inferior OS (p = 0.048). Our findings suggest that the TP53 and ATM genes could be involved in the molecular pathophysiology of primary DLBCL CNS, whereas mutations in the PTEN and SMO genes could affect survival regardless of the initial treatment approach.  相似文献   
10.
Crosslinking enzymes are frequently used in bioprocessing of dairy products. The aim of this study was to examine the effects of enzymatic crosslinking on IgE binding, allergenicity and digestion stability of β‐casein (CN). β‐CN was crosslinked by transglutaminase, tyrosinase, mushroom tyrosinase/caffeic acid and laccase/caffeic acid. The IgE binding to β‐CN was compared in vitro by CAP inhibition assay, ELISA inhibition as well as ex vivo by basophil activation assay. Crosslinked CNs were digested by simulated gastric fluid for 15 and 60 min and obtained digests analyzed for their ability to inhibit IgE binding by CAP inhibition assay and SDS‐PAGE. The ability of crosslinked CNs to activate basophils was significantly reduced in seven patients in the case of CN crosslinked by laccase and moderately reduced in the case of tyrosinase/caffeic acid crosslinked CN (in two cow's milk allergy patients tested with different allergen concentrations). The response to various crosslinked CNs differed individually among patients' sera tested by ELISA inhibition assay. The presence of caffeic acid hampered digestion by pepsin, and this effect was most pronounced for the tyrosinase/caffeic acid crosslinked CN. The laccase/caffeic acid and mushroom tyrosinase/caffeic acid had the highest potential in mitigating IgE binding and allergenicity of the β‐CN out of all investigated enzymes. The presence of a small phenolic compound also increased digestion stability of β‐CN.  相似文献   
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