BACKGROUND: Stability in simulated gastric fluid is supposed to be an important parameter for the estimation of food allergenicity. In the present study, the digestive stability of allergenic protein ...tropomyosin (TM) and other food proteins from Grass prawn and Pacific white shrimp in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) digestion assay system was investigated and comparatively studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS‐PAGE), western blotting, and inhibition enzyme‐linked immunosorbent assay (ELISA). RESULTS: In the SGF system, proteins such as actin and myosin heavy chain (MHC) were rapidly degraded within a short period of time, while TM was relatively resistant to pepsin digestion. In the SIF system, MHC was also easily decomposed, while TM and actin were resistant to digestion. Western blotting using a specific polyclonal antibody against TM indicated that the degradation pattern of shrimp TM by SGF and SIF was almost unaffected by the presence of other myofibrillar proteins. Further study by IgE immunoblotting and inhibition ELISA using sera from crustacean‐allergic patients indicated that IgE binding of TM was decreased. CONCLUSION: Proteinase digestion is effective in reducing IgE binding of shrimp TM. It is also of interest to notice that Pacific white shrimp TM had higher digestion stability than Grass prawn TM. However, Pacific white shrimp TM revealed enhanced IgE binding over that of TM from Grass prawn and thus it is possibly more allergenic. Copyright
Introduction
Whether transplanted cardiac stem cells (CSCs) and mesenchymal stem cells (MSCs) improved ventricular fibrillation threshold (VFT) similarly is still unclear. We sought to compare the ...effects of the CSC and MSC transplantation on the electrophysiological characteristics and VFT in rats with myocardial infarction (MI).
Methods
MI was induced in 30 male Sprague–Dawley rats. Two weeks later, animals were randomized to receive 5 × 10
6
CSCs labeled with PKH26 in PBS or 5 × 10
6
MSCs labeled with PKH26 in phosphate buffer solution(PBS) or PBS alone injection into the infarcted anterior ventricular free wall. Six weeks after the injection, electrophysiological characteristics and VFT were measured. Labeled CSCs and MSCs were observed in 5 μm cryostat sections from each heart.
Results
Malignant ventricular arrhythmias were significantly (
P
= 0.0055) less inducible in the CSC group than the MSC group. The VFTs were improved in the CSC group compared with the MSC group. Labeled CSCs and MSCs were identified in the infarct zone and infarct marginal zone. Labeled CSCs expressed Connexin-43, von Willebrand factor, α-smooth muscle actin and α-sarcomeric actin,while the Labeled MSCs expressed von Willebrand factor, α-smooth muscle actin and α-sarcomeric actin in vivo.
Conclusions
After 6 weeks of cell transplantation, CSCs are superior to MSCs in modulating the electrophysiological abnormality and improving the VFT in rats with MI. CSCs and MSCs express markers that suggest muscle, endothelium and vascular smooth muscle phenotypes in vivo, but MSCs rarely express Connexin-43.
In this letter, a Ta 2 O 5 /a-IGZO thin film transistor (TFT) was directly stacked on a crystalline-Si interdigitated back contact (IBC) photovoltaic (PV) cell to create a self-powered solar switch. ...The a-IGZO TFT and IBC PV cell were integrated into a single chip without an external circuit. This device exhibits switching property induced by illumination. The results show that it can be switched even under a low solar illumination of 300 W/m 2 due to the low threshold voltage of the a-IGZO TFT (0.25 V). The ON/OFF current contrast ratio was measured to be ~20 under 1-sun illumination. The fabrication process and characteristics of this device make it suitable and practicable for use as a self-powered solar switch.
We report the adsorption of Au nanoparticles onto the surface of GaN nanowires (NWs) through photo-enhanced chemical reaction and the fabrication of GaN NW field emitters. With the adsorption of Au ...nanoparticles, it is found that threshold field and work function are reduced from 8.29 V/mm and 4.1 eV to 6.67 V/mm and 3.2 eV, respectively. These improvements could be attributed to the larger band distortion and more electrons accumulation so that more electrons could be emitted for the GaN NW field emitters with Au nanoparticles.
Si nanowire (NW)-based photovoltaic devices were fabricated using NWs grown at various temperatures. It was found that the average length and average diameter of the NWs increased as the growth ...temperature was increased from 450°C to 620°C. It was also found that the NWs became sparser with increasing growth temperature. The reflectance spectra and I-V characteristics indicate that the average reflectances were about 9%, 15%, and 18% and that the photovoltaic conversion efficiencies were 4.1%, 2.33%, and 1.87% for Si NWs grown at 450°C, 550°C, and 620°C, respectively. The experiment results show that the largest fill factor (74%) and external quantum efficiency (40%) (for a wavelength of 740 nm) were achieved for Si NWs grown at 450°C.
The concerted activity of intestinal microbes is crucial to the health and development of their host organisms. Investigation of microbial interactions in the gut should deepen our understanding of ...how these micro-ecosystems function. Due to advances in Next Generation Sequencing (NGS) technologies, various bioinformatic strategies have been proposed to investigate these microbial interactions. However, due to the complexity of the intestinal microbial community and difficulties in monitoring their interactions, at present there is a gap between the theory and biological application. In order to construct and validate microbial relationships, we first induce a community shift from simple to complex by manipulating artificial hibernation (AH) in the treefrog
. To monitor community growth and microbial interactions, we further performed a time-course screen using a 16S rRNA amplicon approach and a Lotka-Volterra model. Lotka-Volterra models, also known as
, predict the dynamics of microbial communities and how communities are structured and sustained. An interaction network of gut microbiota at the genus level in the treefrog was constructed using Metagenomic Microbial Interaction Simulator (MetaMIS) package. The interaction network obtained had 1,568 commensal, 1,737 amensal, 3,777 mutual, and 3,232 competitive relationships, e.g.,
has a commensal relationship with
. To validate the interacting relationships, the gut microbe composition was analyzed after probiotic trials using single strain (
, and
, respectively) and a combination of
, and
, because of the cooperative relationship among their respective genera identified in the interaction network. After a 2 week trial, we found via 16S rRNA amplicon analysis that the combination of cooperative microbes yielded significantly higher probiotic concentrations than single strains, and the immune response (interleukin-10 expression) also significantly changed in a manner consistent with improved probiotic effects. By taking advantage of microbial community shift from simple to complex, we thus constructed a reliable microbial interaction network, and validated it using probiotic strains as a test system.
BACKGROUND: China is the largest producer and consumer of aquatic products in the world; however, many people in China suffer from allergies upon consuming crab. Stability in simulated gastric fluid ...is regarded as an important parameter for the estimation of food allergenicity.RESULTS: The digestive stability of allergenic protein tropomyosin (TM) and other food proteins from Chinese mitten crab in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) digestion assay systems was investigated and compared by SDS-PAGE, western blot and inhibition ELISA. In the SGF system, proteins such as the original band of myosin heavy chain (MHC) and actin were rapidly degraded within a short period of time, while TM was relatively resistant to pepsin digestion. In the SIF system, MHC was easily decomposed, while TM and actin were similarly resistant to digestion. Further study by IgE immunoblotting and inhibition ELISA using sera from crab-allergic patients indicated that allergenicity of TM was partially decreased.CONCLUSION: Chinese mitten crab major allergen TM was resistant to pepsin while relatively susceptible to trypsin and chymotrypsin digestion. Both SDS-PAGE using purified TM and western blot using myofibrillar proteins indicated that the degradation pattern of TM by SGF and SIF was not affected by the presence of other myofibrillar proteins. Inhibition ELISA results revealed that proteinase digestion is effective in reducing the allergenicity of crab TM. Copyright
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