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Background: Non‐apoptotic cell death is presently emerging as a potential direction to overcome the apoptosis resistance of cancer cells. In the current study, a natural plant agent α‐hederin (α‐hed) induces caspase‐independent paraptotic modes of cell death. Purpose: The present study is aimed to investigate the role of α‐hed induces paraptosis and the associated mechanism of it. Methods: The cell proliferation was detected by CCK‐8. The cytoplasm organelles were observed under electron microscope. Calcium (Ca2+) level was detected by flow cytometry. Swiss Target Prediction tool analyzed the potential molecule targets of α‐hed. Molecular docking methods were used to evaluate binding abilities of α‐hed with targets. The expressions of genes and proteins were analyzed by RT‐qPCR, western blotting, immunofluorescence, and immunohistochemistry. Xenograft models in nude mice were established to evaluate the anticancer effects in vivo. Results: α‐hed exerted significant cytotoxicity against a panel of CRC cell lines by inhibiting proliferation. Besides, it induced cytoplasmic vacuolation in all CRC cells. Electron microscopy images showed the aberrant dilation of endoplasmic reticulum and mitochondria. Both mRNA and protein expressions of Alg‐2 interacting proteinX (Alix), the marker of paraptosis, were inhibited by α‐hed. Besides, both Swiss prediction and molecular docking showed that the structure of α‐hed could tightly target to GPCRs. GPCRs were reported to activate the phospholipase C (PLC)‐β3/ inositol 1,4,5‐trisphosphate receptor (IP3R)/ Ca2+/ protein kinase C alpha (PKCα) pathway, and we then found all proteins and mRNA expressions of PLCβ3, IP3R, and PKCα were increased by α‐hed. After blocking the GPCR signaling, α‐hed could not elevate Ca2+ level and showed less CRC cell cytotoxicity. MAPK cascade is the symbol of paraptosis, and we then demonstrated that α‐hed activated MAPK cascade by elevating Ca2+ flux. Since non‐apoptotic cell death is presently emerging as a potential direction to overcome chemo‐drug resistance, we then found α‐hed also induced paraptosis in 5‐fluorouracil‐resistant (5‐FU‐R) CRC cells, and it reduced the growth of 5‐FU‐R CRC xenografts. Conclusions: Collectively, our findings proved α‐hed as a promising candidate for inducing non‐apoptotic cell death, paraptosis. It may overcome the resistance of apoptotic‐based chemo‐resistance in CRC. [ABSTRACT FROM AUTHOR]

Coptis chinensis Franch. and Sophora flavescens Ait. is a herbal pair frequently used in treating ulcerative colitis. However, the bio‐disposition profile of the major components in the inflamed gut remains unclear, which is essential to understand the pharmacological material basis of this herb pair. Here we established an integral quantitative and chemometric method to deduce the colonic metabolism differences of this herbal pair in normal and colitis mice. With this LC‐MS method, a total of 41 components have been found in the Coptis chinensis Franch. and Sophora flavescens Ait. extract, and 28 metabolites were found in the colon after oral administration. Alkaloid and its phase I metabolites were the main components in the colon of normal and colitis mice. The results of principal component analysis at 6 h after oral administration showed significant colonic metabolism differences between normal and colitis mice. Heamap results showed that colitis induced significant changes in the colonic bio‐disposition of this herbal pair extract. In particular, in the context of colitis, the phase I metabolism of berberine, coptisine, jatrorrhizine, palmatine,and epiberberine has been inhibited. These results may provide a basis for understanding the pharmacological material basis of Coptis chinensis Franch. and Sophora flavescens Ait. in treating ulcerative colitis. [ABSTRACT FROM AUTHOR]

Aqueous extract of toad skin (named as Cinobufacini or Huachansu) provides plentiful sources of bioactive peptides that remain undetected and unidentified. High‐resolution mass spectrometry‐based peptidomics platforms have developed into a major approach to the discovery of natural peptides, with data‐dependent acquisition modes providing a wealth of peptide profiling information. In this study, we used a gel‐ and HLB (a solid phase extraction cartridge)‐based two‐dimensional separation and purification system and nano‐liquid chromatography‐tandem mass spectrometry‐based peptidomic studies with homology matching for the identification of peptides from Cinobufacini. We evaluated 232 multi‐charged peptides and found several specific peptides, some of which were validated by target parallel reaction monitoring mode. These peptides are the first to be identified in Cinobufacini and are completely different from ones identified in toad venom. So, this mapping provides key peptide information for the quality control of Bufo bufo gargarizans skin and its preparation. [ABSTRACT FROM AUTHOR]

Scutellaria barbata D. Don (S. barbata) is one of the most frequently used anticancer herb medicine in China. Mechanistic understanding of the biological activities of S. barbata is hindered by limited knowledge regarding its components and metabolic profile. In this study, ultra‐high‐performance liquid chromatography coupled with high resolution mass spectrometry (quadrupole time‐of‐flight mass spectrometry) was used to identify the chemical constituents in S. barbata and their metabolic profiles in rats. By applying cleavage rules and comparison with reference substances, 89 components were identified in S. barbata, which included 45 flavonoids, 28 diterpenoids, 10 phenolics, and 6 others. A total of 110 compounds, including 32 prototype compounds and 78 metabolites, were identified or tentatively characterized in vivo. Methylation, sulfonation, and glucuronidation were the main metabolic pathways, which could be attributed to the fact that several of the compounds in S. barbata have phenolic hydroxyl groups. This is the first systematic study on the chemical constituents and in vivo metabolic profile of S. barbata. The analytical method features a quick and comprehensive dissection of the chemical composition and metabolic profile of S. barbata and provides a basis for exploring its various biological activities. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to evaluate the anti‐cancer property of Lobetyolin on colorectal cancer and explore its potential mechanism. Lobetyolin was incubated with HCT‐116 cells in the absence or presence of ASCT2 inhibitor Benser or p53 inhibitor Pifithrin‐α. The levels of glutamine, glutamic acid, α‐ketoglutarate, ATP and GSH were determined to measure the glutamine metabolism. Annexin V‐FITC/PI staining and TUNEL assay were applied to estimate the apoptotic condition. The levels of ASCT2 were examined by RT‐qPCR, Western blot and immunofluorescence staining. The expressions of cleaved‐caspase‐3, caspase‐3, cleaved‐caspase‐7, caspase‐7, cleaved‐PARP, PARP, p53, p21, bax and survivin were detected using Western blot analysis. As a result, the treatment with Lobetyolin effectively induced apoptosis and glutamine metabolism in HCT‐116 cells through ASCT2 signalling. The inhibition of ASCT2 reduced the glutamine‐related biomarkers and augmented the apoptotic process. We further found that the effect of Lobetyolin on HCT‐116 was related to the expressions of p21 and bax, and transportation of p53 to nucleus. The inhibition of p53 by Pifithrin‐α promoted the inhibitory effect of Lobetyolin on ASCT2‐mediated apoptosis. Lobetyolin also exerted anti‐cancer property in nude mice. In conclusion, the present work suggested that Lobetyolin could induce the apoptosis via the inhibition of ASCT2‐mediated glutamine metabolism, which was possibly governed by p53. [ABSTRACT FROM AUTHOR]

Colon cancer represents the third most common malignancy worldwide. New drugs with high efficaciousness and safety for the treatment of colon cancer are urgently needed in clinical context. Here, we were aimed to evaluate the antitumor activity of the natural compound α-hederin in human colon cancer cells. We treated SW620 cells with interleukin-6 (IL-6) in vitro to mimic the paracrine inflammatory microenvironment of tumor cells. α-Hederin concentration dependently reduced the viability of IL-6-stimulated SW620 cells. α-Hederin increased the number of IL-6-stimulated SW620 cells at the G2/M phase and reduced the mRNA and protein expression of cyclin B1 and CDK1. Moreover, α-hederin induced apoptosis and loss of mitochondrial membrane potential in IL-6-stimulated SW620 cells. α-Hederin downregulated Bcl-2 expression, upregulated Bax expression, and promoted cytochrome c release from mitochondria into cytoplasm. Additionally, α-hederin elevated the levels of cleaved-caspase-9, cleaved-caspase-3, and cleaved-PARP, but had little effects on the levels of cleaved-caspase-8. Moreover, α-hederin prevented the nuclear translocation of nuclear factor-κB (NF-κB) and reduced the phosphorylation of IκBα and IKKα, suggesting the blockade of NF-κB signaling. NF-κB inhibitor PDTC not only produced similar proapoptotic effects on IL-6-stimulated SW620 cells as α-hederin did, but also synergistically enhanced α-hederin’s proapoptotic effects. Furthermore, α-hederin inhibited the phosphorylation of ERK in IL-6-stimulated SW620 cells, which was involved in α-hederin blockade of NF-κB nuclear translocation. Altogether, α-hederin suppressed viability, induced G2/M cell cycle arrest, and stimulated mitochondrial and caspase-dependent apoptosis in colon cancer cells, which were associated with disruption of NF-κB and ERK pathways, suggesting α-hederin as a promising candidate for intervention of colon cancer. [ABSTRACT FROM AUTHOR]

We present in this paper an alternative method for understanding user-chosen passwords. In password research, much attention has been given to increasing the security and usability of individual passwords for common users. Few of them focus on the relationships between passwords; therefore we explore the relationships between passwords: modification-based, similarity-based, and probability-based. By regarding passwords as vertices, we shed light on how to transform a dataset of passwords into a password graph. Subsequently, we introduce some novel notions from graph theory and report on a number of inner properties of passwords from the perspective of graph. With the assistance of Python Graph-tool, we are able to visualize our password graph to deliver an intuitive grasp of user-chosen passwords. Five real-world password datasets are used in our experiments to fulfill our thorough experiments. We discover that (1) some passwords in a dataset are tightly connected with each other; (2) they have the tendency to gather together as a cluster like they are in a social network; (3) password graph has logarithmic distribution for its degrees. Top clusters in password graph could be exploited to obtain the effective mangling rules for cracking passwords. Also, password graph can be utilized for a new kind of password strength meter. [ABSTRACT FROM AUTHOR]

A comprehensive strategy was designed for the quality assessment of Fructus Ligustri Lucidi, a well-known and commonly used herbal medicine in clinical practice in China. First, a simple and stable method of high-performance liquid chromatography was developed for the simultaneous quantitative analysis of six compounds, namely, salidroside, nuzhenide, specnuezhenide, oleanic acid, ursolic acid, and acetyl oleanic acid in Fructus Ligustri Lucidi. The separation of analytes was conducted on a C18 column (200 mm × 4.6 mm, 5 μm) at 30°C, and the wavelength of UV detector was set at 210 nm. In quantitative analysis, all of the calibration curves showed good linear regression ( R2 > 0.9994) within the tested ranges, and the mean recoveries of three different concentrations ranged from 95.21-102.34%. The described method was applied to determine 11 batches of samples collected from different stores in China. Then multiple chemometrics analysis including hierarchical cluster analysis and principal component analysis were performed to classify samples and search significant compounds. Three notable compounds, specnuezhenide, oleanic acid, and acetyl oleanic acid, were discovered for better quality control compared with those stated in the China pharmacopeia. The results demonstrated that this strategy could be readily utilized for the comprehensive quality control of Fructus Ligustri Lucidi. [ABSTRACT FROM AUTHOR]

A novel series of 2-hydroxy-3-(nitroimidazolyl)-propyl-derived quinolones 6a- o were synthesized and evaluated for their in vitro antibacterial activity. Most of the target compounds exhibited potent activity against Gram-positive strains. Among them, moxifloxacin analog 6n displayed the most potent activity against Gram-positive strains including S. epidermidis (MIC = 0.06 μg/mL), MSSE (MIC = 0.125 μg/mL), MRSE (MIC = 0.03 μg/mL), S. aureus (MIC = 0.125 μg/mL), MSSA (MIC = 0.125 μg/mL), (MIC = 2 μg/mL). Its activity against MRSA was eightfold more potent than reference drug gatifloxacin. Finally, docking study of the target compound 6n revealed that the binding model of quinolone nucleus was similar to that of gatifloxacin and the 2-hydroxy-3-(nitroimidazolyl)-propyl group formed two additional hydrogen bonds. [ABSTRACT FROM AUTHOR]

Inhibition of dipeptidyl peptidase IV is an important approach for the treatment of type-2 diabetes. In this study, we reported a multistage virtual screening workflow that integrated 3D pharmacophore models, structural consensus docking, and molecular mechanics/generalized Born surface area binding energy calculation to identify novel dipeptidyl peptidase IV inhibitors. After screening our in-house database, two hit compounds, HWL-405 and HWL-892, having persistent high performance in all stages of virtual screening were identified. These two hit compounds together with several analogs were synthesized and evaluated for in vitro inhibition of dipeptidyl peptidase IV. The experimental data indicated that most designed compounds exhibited significant dipeptidyl peptidase IV inhibitory activity. Among them, compounds 35f displayed the greatest potency against dipeptidyl peptidase IV in vitro with the IC50 value of 78 n m. In an oral glucose tolerance test in normal male Kunming mice, compound 35f reduced blood glucose excursion in a dose-dependent manner. [ABSTRACT FROM AUTHOR]

Long-term macrolides are increasingly being prescribed for stable bronchiectasis. This meta-analysis assessed the clinical effect of this treatment in bronchiectasis. A systematic review and meta-analysis were carried out. All randomized, controlled trials ( RCT) comparing long-term macrolides with placebo and/or usual medical care, with outcome measures relating to efficacy and safety were selected. Nine RCT recruiting 530 patients were included. Compared with placebo and/or usual medical care, long-term macrolides significantly reduced the risk of the exacerbations (number of participants with exacerbations (relative risk = 0.70, 95% confidence interval ( CI) 0.60-0.82, P < 0.00001); average exacerbations per participant (weighted mean difference = −1.01, 95% CI −1.35 to −0.67, P < 0.00001)), the St George's Respiratory Questionnaire total scores (weighted mean difference = −5.39 95% CI −9.89 to −0.88, P = 0.02), dyspnoea scale (weighted mean difference = −0.31 95% CI −0.42 to −0.20, P < 0.00001), 24-h sputum volume ( P < 0.00001), and attenuated the decline of forced expiratory volume in 1 s (weighted mean difference 0.02 L, 95% CI 0.00-0.04, P = 0.01). Eradication of pathogens ( P = 0.06), overall rate of adverse events ( P = 0.61), and emergence of new pathogens ( P = 0.61) were not elevated, while gastrointestinal events increased significantly with macrolides ( P = 0.0001). Macrolide resistance increased, but a meta-analysis was not possible due to the diversity of parameters. Long-term use of macrolides appears to be a treatment option for stable bronchiectasis. The results of this review justify further investigation about adding this intervention to the treatment regimens of bronchiectasis. [ABSTRACT FROM AUTHOR]

This article deals with (1) synthesis of novel cyclic carbonate monomer (2‐oxo [1,3]dioxan‐5‐yl)carbamic acid benzyl ester (CAB) containing protected amino groups; (2) ring‐opening copolymerization of the cyclic monomer with L‐lactide (LA) to provide novel degradable poly(ester‐carbonate)s with functional groups; (3) removal of the protective benzyloxycarbonyl (Cbz) groups by catalytic hydrogenation to afford the corresponding poly(ester‐co‐carbonate)s with free amino groups; (4) grafting of oligopeptide Gly‐Arg‐Gly‐Asp‐Ser‐Tyr (GRGDSY, abbreviated as RGD) onto the copolymer pendant amino groups in the presence of 1,1′‐carbonyldiimidazole (CDI). The structures of P(LA‐co‐CA/RGD) and its precursor were confirmed by 1H NMR analysis. Cell experiments showed that P(LA‐co‐CA/RGD) had improved adhesion and proliferation behavior. Therefore, the novel RGD‐grafted block copolymer is promising for cell or tissue engineering applications. © Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7022–7032, 2008 [ABSTRACT FROM AUTHOR]