Mechanisms of Calcium-induced Firmness in Fruits, Vegetables, and Mushrooms

Six fractions from mushrooms (MFs), as cytoplasmic proteins (F1), cell membrane proteins (F2), alkali-soluble cell wall glucans (F3a), cell wall proteins (F3b), cell wall beta-glucans (F4a), and chitin (F4b) and five fractions from both apples (AFs) and cucumbers (CFs), as cytoplasmic proteins (F1), cell membrane proteins (F2), cell wall proteins (F3), pectic substances (F4), and cellulose (F5) were extracted and analyzed for their neutral carbohydrates, proteins, aminosugar material, soluble phenolics, and pectic substances. The dominant compounds consisted of the following: proteins in MF1, proteins and neutral polysaccharides in MF2, neutral polysaccharides in MF3a, neutral polysaccharides in MF3b, neutral polysaccharides and chitinous material in MF4a, neutral polysaccharides and chitinous material in MF4b; pectic substances in AF1, AF2 and AF4, proteins in AF3, neutral polysaccharides in AF5; proteins in CF1, CF2, and CF3; pectic substances in CF4, and neutral polysaccharides in CF5. Experiments for binding calcium (CaCl2) to fraction solids were performed in 10 mM Tris-HCl buffer (pH 7.0). The calcium-binding capacity was obtained by both Ion Selective Electrode (ISE) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) measurements. The results indicated that calcium-binding capacity of fractions differed significantly in the order of MF1\u3eMF2\u3eMF3a ≥ MF3b≥MF4b~MF4a for mushroom fractions. AF2 and AF4 showed higher binding capacity than AF1 and AF5 for apple fractions. For cucumber, CF1, CF2, and CF4 showed higher binding capacity than CF3 and CF5. The results revealed that calcium was bound by all fractions, but those fractions dominantly composed of cytoplasmic proteins (MF1) and cell membrane proteins (MF2) in mushroom fractions, pectic substances (AF4) and cell membrane proteins (AF2) in apple fractions, cytoplasmic proteins (CF1), cell membrane proteins (CF2), and pectic substances (CF4) in cucumber fractions possessed higher capacities. The binding of calcium to the biopolymers was further investigated by Isothermal Titration Calorimetry (ITC) using pectin and bovine serum albumin (BSA). The results confirmed that interaction of calcium with pectic substances plays a primary role in firmness improvement. However, data also indicated that interactions between calcium and cytoplasmic and/ or membrane proteins may contribute to the firmness improvement in calcium-treated mushrooms, apples, and cucumbers

A Case of Cutaneous Nocardiosis with Involvement of the Trachea, Anterior Mediastinum and Sternum

Nocardiosis is a rare infectious disease due to Nocardia infections. In this report, we present a rare case of cutaneous nocardiosis with involvement of the trachea, anterior mediastinum and sternum. The strain of Nocardia has been isolated from bacterial culture of infected tissue. 16s rRNA sequencing confirmed that it contained the Nocardia genus. The patient was successfully treated with Co-SMZ

What Makes Video Ads Viral: Quantifying the Impact of Marketer- and User-Generated Content

Past research on viral advertising focuses on the direct impact of MGC (i.e. Marketer-Generated Content) on the content viral ability. However, it is not clear how this impact of MGC takes place through the mediating effect of UGC (i.e. User-Generated Content) in this process. In this study, we examine the mechanism that makes a video ad viral by taking into account the impact of both MGC (i.e. video content) and UGC (i.e. video comments) in YouTube. AMT (Amazon Mechanical Turk) and Text-Mining Method are combined to extract the characteristics embedded in MGC and UGC

Molecular characterization of cathepsin B from Clonorchis sinensis excretory/secretory products and assessment of its potential for serodiagnosis of clonorchiasis

<p>Abstract</p> <p>Background</p> <p>Cathepsin cysteine proteases play multiple roles in the life cycle of parasites such as food uptake, immune invasion and pathogenesis, making them valuable targets for diagnostic assays, vaccines and drugs. The purpose of this study was to identify a cathepsin B of <it>Clonorchis sinensis </it>(<it>Cs</it>CB) and to investigate its diagnostic value for human helminthiases.</p> <p>Results</p> <p>The predicted amino acid sequence of the cathepsin B of <it>C. sinensis </it>shared 63%, 52%, 50% identity with that of <it>Schistosoma japonicum</it>, <it>Homo sapiens </it>and <it>Fasciola hepatica</it>, respectively. Sequence encoding proenzyme of <it>Cs</it>CB was overexpressed in <it>Escherichia coli</it>. Reverse transcription PCR experiments revealed that <it>Cs</it>CB transcribed in both adult worm and metacercaria of <it>C. sinensis</it>. <it>Cs</it>CB was identified as a <it>C. sinensis </it>excretory/secretory product by immunoblot assay, which was consistent with immunohistochemical localization showing that <it>Cs</it>CB was especially expressed in the intestine of <it>C. sinensis </it>adults. Both ELISA and western blotting analysis showed recombinant <it>Cs</it>CB could react with human sera from clonorchiasis and other helminthiases.</p> <p>Conclusions</p> <p>Our findings revealed that secreted CsCB may play an important role in the biology of C. sinensis and could be a diagnostic candidate for helminthiases.</p

A PH Domain in ACAP1 Possesses Key Features of the BAR Domain in Promoting Membrane Curvature

SummaryThe BAR (Bin-Amphiphysin-Rvs) domain undergoes dimerization to produce a curved protein structure, which superimposes onto membrane through electrostatic interactions to sense and impart membrane curvature. In some cases, a BAR domain also possesses an amphipathic helix that inserts into the membrane to induce curvature. ACAP1 (Arfgap with Coil coil, Ankyrin repeat, and PH domain protein 1) contains a BAR domain. Here, we show that this BAR domain can neither bind membrane nor impart curvature, but instead requires a neighboring PH (Pleckstrin Homology) domain to achieve these functions. Specific residues within the PH domain are responsible for both membrane binding and curvature generation. The BAR domain adjacent to the PH domain instead interacts with the BAR domains of neighboring ACAP1 proteins to enable clustering at the membrane. Thus, we have uncovered the molecular basis for an unexpected and unconventional collaboration between PH and BAR domains in membrane bending

N6-(2-Hydroxyethyl) Adenosine From Cordyceps cicadae Ameliorates Renal Interstitial Fibrosis and Prevents Inflammation via TGF-β1/Smad and NF-κB Signaling Pathway

Renal interstitial fibrosis is characterized by inflammation and an excessive accumulation of extracellular matrix, which leads to end-stage renal failure. Our previous studies have shown that a natural product from Cordyceps cicadae can ameliorate chronic kidney diseases. N6-(2-Hydroxyethyl) adenosine (HEA), a physiologically active compound in C. cicadae, has been identified as a Ca2+ antagonist and an anti-inflammatory agent in pharmacological tests. However, its role in renal interstitial fibrosis and the underlying mechanism remains unclear. Here, unilateral ureteral obstruction (UUO) was used to induce renal interstitial fibrosis in male C57BL/6 mice. Different doses of HEA (2.5, 5, and 7.5 mg/kg) were given by intraperitoneal injection 24 h before UUO, and the treatment was continued for 14 days post-operatively. Histologic changes were examined by hematoxylin &amp; eosin, Masson’s trichrome, and picrosirius red stain. Quantitative real-time PCR analysis, enzyme-linked immunosorbent assays, immunohistochemistry, and western blot analysis were used to evaluate proteins levels. And the results showed that HEA significantly decreased UUO-induced renal tubular injury and fibrosis. In vivo, HEA apparently decreased UUO-induced inflammation and renal fibroblast activation by suppression of the NF-κB and TGF-β1/Smad signaling pathway. In vitro, HEA also obviously decreased lipopolysaccharide-induced inflammatory cytokine level in RAW 264.7 cells and TGF-β1-induced fibroblast activation in NRK-49F cells by modulating NF-κB and TGF-β1/Smad signaling. In general, our findings indicate that HEA has a beneficial effect on UUO-induced tubulointerstitial fibrosis by suppression of inflammatory and renal fibroblast activation, which may be a potential therapy in chronic conditions such as renal interstitial fibrosis

The alteration of the structure and macroscopic mechanical response of porcine patellar tendon by elastase digestion

Background: The treatment of patellar tendon injury has always been an unsolved problem, and mechanical characterization is very important for its repair and reconstruction. Elastin is a contributor to mechanics, but it is not clear how it affects the elasticity, viscoelastic properties, and structure of patellar tendon.Methods: The patellar tendons from six fresh adult experimental pigs were used in this study and they were made into 77 samples. The patellar tendon was specifically degraded by elastase, and the regional mechanical response and structural changes were investigated by: (1) Based on the previous study of elastase treatment conditions, the biochemical quantification of collagen, glycosaminoglycan and total protein was carried out; (2) The patellar tendon was divided into the proximal, central, and distal regions, and then the axial tensile test and stress relaxation test were performed before and after phosphate-buffered saline (PBS) or elastase treatment; (3) The dynamic constitutive model was established by the obtained mechanical data; (4) The structural relationship between elastin and collagen fibers was analyzed by two-photon microscopy and histology.Results: There was no statistical difference in mechanics between patellar tendon regions. Compared with those before elastase treatment, the low tensile modulus decreased by 75%–80%, the high tensile modulus decreased by 38%–47%, and the transition strain was prolonged after treatment. For viscoelastic behavior, the stress relaxation increased, the initial slope increased by 55%, the saturation slope increased by 44%, and the transition time increased by 25% after enzyme treatment. Elastin degradation made the collagen fibers of patellar tendon become disordered and looser, and the fiber wavelength increased significantly.Conclusion: The results of this study show that elastin plays an important role in the mechanical properties and fiber structure stability of patellar tendon, which supplements the structure-function relationship information of patellar tendon. The established constitutive model is of great significance to the prediction, repair and replacement of patellar tendon injury. In addition, human patellar tendon has a higher elastin content, so the results of this study can provide supporting information on the natural properties of tendon elastin degradation and guide the development of artificial patellar tendon biomaterials