127 research outputs found
Radical Scavenging Activity of Black Currant (\u3ci\u3eRibes nigrum\u3c/i\u3e L.) Extract and Its Inhibitory Effect on Gastric Cancer Cell Proliferation via Induction of Apoptosis
A black currant extract (BCE) was prepared and its antiproliferative activity against gastric cancer SGC-7901 cells was investigated. Strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical scavenging activities and a high reducing power were confirmed with BCE. BCE inhibited the proliferation of SGC-7901 cells in a dose- and time-dependent manner, and the IC50 were 12.7, 10.2 and 9.0 mg/mL for 12, 24 and 48 h, respectively. Morphologic observations with inverted and fluorescence microscopes yielded vivid evidence of cell shrinkage, formation of cytoplasmic filaments, condensation of nuclear chromatin, and cell apoptosis in the presence of BCE. Flow cytometric analysis also showed that BCE treatment at concentrations of 10–20 mg/mL resulted in marked reductions of viable cells. The high concentration of phenolic compounds present in the BCE (12.2 mg/mL), including six prominent anthocyanins identified by HPLC–ESI-MS2, appeared to be responsible for BCE’s antiradical activity and anticancer effects. These findings of inhibition of SGC-7901 cells and induction of apoptosis suggest that black currant may contribute to the reduction in gastric cancer risk
Research Progress on the Formation and Chromogenic Mechanism of Zinc Protoporphyrin and Its Replacement for Nitrite in Meat Products
Nitrite has been used widely in meat products because of its unique properties, especially its role in promoting the color development of meat products and its bacteriostatic effect. Searching for nitrite alternatives has become an urgent topic for the meat industry due to consumers’ concerns about the potential health risk associated with nitrite and consumers’ demand for natural products with a clean label. As a natural pigment substance, zinc protoporphyrin (ZnPP) has a significant advantage in promoting the color development of meat products. This paper introduces the properties, formation mechanism, quantitative analysis and distribution in meat products of ZnPP, with a focus on the factors influencing ZnPP formation. Finally, future prospects for the application of ZnPP are discussed in order to provide new ways for the development of the low-nitrate meat processing industry
Hyperin up-regulates miR-7031-5P to promote osteogenic differentiation of MC3T3-E1 cells
Objective. To investigate the effects of Hyperin (Hyp) on osteogenic differentiation of MC3T3E1 cells. Methods. Differentially expressed miRNA was screened by miRNA Microarray. miR-7031-5P overexpression and knockdown MC3T3-E1 cell models were constructed by transfecting miR-7031-5P mimics and inhibitor. Alizarin red staining (ARS) assay was used to observe the formation of mineralized nodules in MC3T3-E1 cells. ALP activity was detected by using ALP detection kit. Western blot assay was used to examine the changes in osteogenic differentiation-related proteins. The relationship between miR-7031-5P and Wnt7a was revealed by dual luciferase report experiments. Results. We found that miR-7031-5P was upregulated in MC3T3-E1 cells after Hyp treatment. The results indicated that compared with the untreated group, Hyp promoted the formation of mineralized nodules and the alkaline phosphatase (ALP) activity of MC3T3-E1 cells via overexpressing miR-7031-5P. Besides, elevated miR-7031-5P increased OPN, COL1A1, and Runx2 mRNA expression. More importantly, Wnt7a was identified as the downstream target gene of miR-70315P promoting osteogenic differentiation of MC3T3-E1 cells. Conclusions. Hyp up-regulated miR-7031-5P to promote osteogenic differentiation of MC3T3-E1 cells by targeting Wnt7
Molecular genetic analysis of phosphomannomutase genes in Triticum monococcum
AbstractIn higher plants, phosphomannomutase (PMM) is essential for synthesizing the antioxidant ascorbic acid through the Smirnoff–Wheeler pathway. Previously, we characterized six PMM genes (TaPMM-A1, A2, B1, B2, D1 and D2) in common wheat (Triticum aestivum, AABBDD). Here, we report a molecular genetic analysis of PMM genes in Triticum monococcum (AmAm), a diploid wheat species whose Am genome is closely related to the A genome of common wheat. Two distinct PMM genes, TmPMM-1 and TmPMM-2, were found in T. monococcum. The coding region of TmPMM-1 was intact and highly conserved. In contrast, two main TmPMM-2 alleles were identified, with TmPMM-2a possessing an intact coding sequence and TmPMM-2b being a pseudogene. The transcript level of TmPMM-2a was much higher than that of TmPMM-2b, and a bacterially expressed TmPMM-2a recombinant protein displayed relatively high PMM activity. In general, the total transcript level of PMM was substantially higher in accessions carrying TmPMM-1 and TmPMM-2a than those harboring TmPMM-1 and TmPMM-2b. However, total PMM protein and activity levels did not differ drastically between the two genotypes. This work provides new information on PMM genes in T. monococcum and expands our understanding on Triticeae PMM genes, which may aid further functional and applied studies of PMM in crop plants
The Effectiveness of Konjac Flour on the Physicochemical and Rheological Properties of the Myofibrillar Proteins of the Common Carp (Cyprinus Carpio)
The effects of konjac flour (KF) on the emulsifying properties, turbidity, rheological properties, gel strength, gel water-binding capacity (WBC), and gel microstructure of the myofibrillar protein (MP) of the common carp (Cyprinus carpio) were investigated. The results showed that the emulsifying activities and gel strength of MP increased first and then decreased with increasing KF concentrations, achieving the highest values at 0.1% KF (P<0.05). Increased KFconcentrations were accompanied by an enhanced gel WBC and increased susceptibility to thermal aggregation (P<0.05). The addition of KF markedly enhanced G' over the entire heating temperature range, and the “peak†G′ values of the 2.0% KF sample were 3.6 times than those of the control samples. The reduced G′′/G′ at the end of the heating process (80°C) revealed that KF addition improved the gel elastic quality and increased the gelling ability of MP. It was determined by observing the gel microstructure that addition of KF reduced empty spaces and produced a more compact and homogeneous MP gel network structure. Overall, these results suggest that KF addition offers an effective approach for improving the MP gel formation ability of the common carp muscle
Fabrication and Antibacterial Performance of Pea Protein Isolate/Pullulan/Allicin Composite Electrospun Nanofibers
Using pea protein isolate (PPI) and pullulan (PUL) as raw materials and allicin (AC) as an antibacterial substance, nanofiber materials were prepared by electrospinning technology. The influence of allicin concentration on the structural and morphological characteristics, diameter distribution and antibacterial effects of nanofibers were investigated. Fourier transform infrared spectroscopy (FTIR) indicated that allicin was wrapped in the composite nanofibers. Scanning electron microscopy (SEM) showed that spherical structures of different sizes appeared around the nanofibers due to the addition of allicin. The size of the spherical structures increased (P < 0.05) with an increase in allicin concentration, while the nanofiber diameter gradually decreased (P < 0.05). With increasing allicin concentration up to 15%, the elastic modulus and tensile strength of the composite nanofibers gradually increased (P < 0.05), and the elongation at break gradually decreased (P < 0.05). Additionally, the composite nanofibers with more than 10% allicin exhibited an obvious bacteriostatic effect, and it was strongest at allicin concentrations of 15% and 20%, with inhibition zone diameters of 16.5 and 12.8 mm against E. coli and S. aureus, respectively. This research will provide data support and a theoretical basis for the development and application of new green food packaging nanomaterials
Genome-wide CRISPR/Cas9 screening for drug resistance in tumors
Genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated nuclease 9 (Cas9) screening is a simple screening method for locating loci under specific conditions, and it has been utilized in tumor drug resistance research for finding potential drug resistance-associated genes. This screening strategy has significant implications for further treatment of malignancies with acquired drug resistance. In recent years, studies involving genome-wide CRISPR/Cas9 screening have gradually increased. Here we review the recent application of genome-wide CRISPR/Cas9 screening for drug resistance, involving mitogen-activated protein kinase (MAPK) pathway inhibitors, poly (ADP-ribose) polymerase inhibitors (PARPi), alkylating agents, mitotic inhibitors, antimetabolites, immune checkpoint inhibitors (ICIs), and cyclin-dependent kinase inhibitors (CDKI). We summarize drug resistance pathways such as the KEAP1/Nrf2 pathway MAPK pathway, and NF-κB pathway. Also, we analyze the limitations and conditions for the application of genome-wide CRISPR/Cas9 screening techniques
PGAweb: A Web Server for Bacterial Pan-Genome Analysis
An astronomical increase in microbial genome data in recent years has led to strong demand for bioinformatic tools for pan-genome analysis within and across species. Here, we present PGAweb, a user-friendly, web-based tool for bacterial pan-genome analysis, which is composed of two main pan-genome analysis modules, PGAP and PGAP-X. PGAweb provides key interactive and customizable functions that include orthologous clustering, pan-genome profiling, sequence variation and evolution analysis, and functional classification. PGAweb presents features of genomic structural dynamics and sequence diversity with different visualization methods that are helpful for intuitively understanding the dynamics and evolution of bacterial genomes. PGAweb has an intuitive interface with one-click setting of parameters and is freely available at http://PGAweb.vlcc.cn/
Novel Evolved Immunoglobulin (Ig)-Binding Molecules Enhance the Detection of IgM against Hepatitis C Virus
Detection of specific antibodies against hepatitis C virus (HCV) is the most widely available test for viral diagnosis and monitoring of HCV infections. However, narrowing the serologic window of anti-HCV detection by enhancing anti-HCV IgM detection has remained to be a problem. Herein, we used LD5, a novel evolved immunoglobulin-binding molecule (NEIBM) with a high affinity for IgM, to develop a new anti-HCV enzyme-linked immunosorbent assay (ELISA) using horseradish peroxidase-labeled LD5 (HRP-LD5) as the conjugated enzyme complex. The HRP-LD5 assay showed detection efficacy that is comparable with two kinds of domestic diagnostic kits and the Abbott 3.0 kit when tested against the national reference panel. Moreover, the HRP-LD5 assay showed a higher detection rate (55.9%, 95% confidence intervals (95% CI) 0.489, 0.629) than that of a domestic diagnostic ELISA kit (Chang Zheng) (53.3%, 95% CI 0.463, 0.603) in 195 hemodialysis patient serum samples. Five serum samples that were positive using the HRP-LD5 assay and negative with the conventional anti-HCV diagnostic ELISA kits were all positive for HCV RNA, and 4 of them had detectable antibodies when tested with the established anti-HCV IgM assay. An IgM confirmation study revealed the IgM reaction nature of these five serum samples. These results demonstrate that HRP-LD5 improved anti-HCV detection by enhancing the detection of anti-HCV IgM, which may have potential value for the early diagnosis and screening of hepatitis C and other infectious diseases
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