Highly secretory expression of recombinant cowpea chlorotic mottle virus capsid proteins in Pichia pastoris and in-vitro encapsulation of ruthenium nanoparticles for catalysis.

The applications of viral protein cages have expanded rapidly into the fields of bionanotechnology and materials science. However, the low-cost production of viral capsid proteins (CPs) on a large scale is always a challenge. Herein, we develop a highly efficient expression system by constructing recombinant Pichia pastoris cells as a "factory" for the secretion of soluble cowpea chlorotic mottle virus (CCMV) CPs. Under optimal induction conditions (0.9 mg/mL of methanol concentration at 30 °C for 96 h), a high yield of approximately 95 mg/L of CCMV CPs was harvested from the fermentation supernatant with CPs purity >90%, which has significantly simplified the rest of the purification process. The resultant CPs are employed to encapsulate Ruthenium (Ru) nanoparticles (NPs) via in-vitro self-assembly to prepare hybrid nanocatalyst, i.e. Ru@virus-like particles (VLPs). The catalytic activity over Ru@VLPs was evaluated by reducing 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The results indicate that, with the protection of protein cages, Ru NPs were highly stabilized during the catalytic reaction. This results in enhanced catalytic activity (reaction rate constant k = 0.14 min-1) in comparison with unsupported citrate-stabilized Ru NPs (Ru-CA) (k = 0.08 min-1). Additionally, comparatively lower activation energy over Ru@VLPs (approximately 32 kJ/mol) than that over Ru-CA (approximately 39 kJ/mol) could be attributed to the synergistic effect between Ru NPs and some functional groups such as amino groups (-NH2) on CPs that weakened the activation barrier of 4-NP reduction. Therefore, enhanced activity and decreased activation energy over Ru@VLPs demonstrated the superiority of Ru@VLPs to unsupported Ru-CA.

The lifespan-extending effects of Nymphaea hybrid root extract in the nematode Caenorhabditis elegans.

Nymphaea hybrid, a water lily from the Nymphaeaceae family, has been found to exhibit some in vivo beneficial effects. In the present study we investigated the lifespan-extending effects of Nymphaea hybrid root extract in the nematode Caenorhabditis elegans. We found that Nymphaea hybrid root extract significantly extended the lifespan of C.elegans and improved its locomotion during aging. Moreover, Nymphaea hybrid root extract increased the resistance of C.elegans to both heat stress and oxidative stress. We found that the ability of Nymphaea hybrid root extract to increase lifespan was independent of its antimicrobial effects and was probably associated with its effects on the reproduction of C.elegans. In addition, the lifespan-extending effects of Nymphaea hybrid root extract were found to be dependent on the insulin/IGF signaling pathway. We also found that total flavones of Nymphaea hybrid could increase survival of C.elegans in both normal and adverse conditions, indicating that total flavones comprise the major fractions with lifespan-extending effects. Therefore, Nymphaea hybrid root extract has lifespan-extending effects in C.elegans and could be developed as a functional food.

Evaluation of unimodal and multimodal information in health communication on GGO-related lung cancer screening: An eye-tracking study.

Aims: To find out a better propaganda and education plan for the popularization of the ground-glass opacities-related (GGO-related) lung cancer screening. Methods and Material: The control group took a lung cancer screening knowledge test directly before receiving the health education. By contrast, the experimental group took the same knowledge test after receiving health education. This study designed unimodal and multimodal materials about GGO-related lung cancer. The text and graph were considered unimodal information, while the video was multimodal information. According to the different information forms they were exposed to, the experimental group was further divided into text, graphic, and video groups. An eye-tracking system was performed to record eye-tracking data synchronously. Results: Compared with the control group, the knowledge test scores of each experimental group were remarkably improved. Furthermore, the graphic group had a significantly higher correct rate on the No. 7 question, while the video group had the lowest. In terms of saccades, the video group had significantly higher speed and amplitude of saccades than the other two groups. In terms of fixation, the interval duration, total duration of whole fixations, and a number of whole fixations of the graphic group were significantly lower than those of the other two groups, while the video group had the highest values for these variables. Conclusions: It was on the unimodal information, such as text and graphics, that people can spend less time and cost to achieve effective acquisition of GGO-related lung cancer screening knowledge.

Molecular Mechanisms for Anti-aging of Low-Vacuum Cold Plasma Pretreatment in Caenorhabditis elegans.

Cold plasma pretreatment has the potential of anti-aging. However, its molecular mechanism is still not clear. Here, cold plasma pretreatment was firstly used to investigate the anti-aging effects of Caenorhabditis elegans using transcriptomic technique. It showed that the optimal parameters of discharge power, processing time, and working pressure for cold plasma pretreatment were separately 100 W, 15 s, and 135 Pa. The released 0.32 mJ/cm2 of the moderate apparent energy density was possibly beneficial to the strong positive interaction between plasma and C. elegans. The longest lifespan (13.67 ± 0.50 for 30 days) was obviously longer than the control (10.37 ± 0.46 for 23 days). Furthermore, compared with the control, frequencies of head thrashes with an increase of 26.01% and 37.31% and those of body bends with an increase of 33.37% and 34.51% on the fourth and eighth day, respectively, indicated movement behavior was improved. In addition, the variation of the enzyme activity of superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) hinted that the cold plasma pretreatment contributed to the enhanced anti-aging effects in nematodes. Transcriptomics analysis revealed that cold plasma pretreatment resulted in specific gene expression. Anatomical structure morphogenesis, response to stress, regulation of biological quality, phosphate-containing compound metabolic process, and phosphorus metabolic process were the most enriched biological process for GO analysis. Cellular response to heat stress and HSF1-dependent transactivation were the two most enriched KEGG pathways. This work would provide the methodological basis using cold plasma pretreatment and the potential gene modification targets for anti-aging study.

Asymmetric Synthesis of Fused-Ring Tetrahydroisoquinolines and Tetrahydro-ß-carbolines from 2-Arylethylamines via a Chemoenzymatic Approach.

While chiral fused-ring tetrahydroisoquinoline (THIQ) and tetrahydro-ß-carboline (THßC) scaffolds have attracted considerable interest due to their wide spectrum of biological activities, the synthesis of optically pure chiral fused-ring THIQs and THßCs remains a challenging task. Herein, a group of active imine reductases were identified to convert the imine precursors into the corresponding enantiocomplementary fused-ring THIQs and THßCs with high enantioselectivity and conversion, establishing an efficient and green chemoenzymatic approach to fused-ring alkaloids from 2-arylethylamines.

ScreenClust: Advanced statistical software for supervised and unsupervised high resolution melting (HRM) analysis.

BACKGROUND: High resolution melting (HRM) is an emerging new method for interrogating and characterizing DNA samples. An important aspect of this technology is data analysis. Traditional HRM curves can be difficult to interpret and the method has been criticized for lack of statistical interrogation and arbitrary interpretation of results. METHODS: Here we report the basic principles and first applications of a new statistical approach to HRM analysis addressing these concerns. Our method allows automated genotyping of unknown samples coupled with formal statistical information on the likelihood, if an unknown sample is of a known genotype (by discriminant analysis or "supervised learning"). It can also determine the assortment of alleles present (by cluster analysis or "unsupervised learning") without a priori knowledge of the genotypes present. CONCLUSION: The new algorithms provide highly sensitive and specific auto-calling of genotypes from HRM data in both supervised an unsupervised analysis mode. The method is based on pure statistical interrogation of the data set with a high degree of standardization. The hypothesis-free unsupervised mode offers various possibilities for de novo HRM applications such as mutation discovery.

Two novel strategies to overcome the resistance to ALK tyrosine kinase inhibitor drugs: Macrocyclic inhibitors and proteolysis-targeting chimeras.

Lung cancer is the most malignant tumor in the worldwide. About 3%-5% non-small cell lung cancer (NSCLC) patients carry anaplastic lymphoma kinase (ALK) gene fusions and receive great benefits from ALK-targeted therapy. However, drug resistance inevitably occurs even with the most potent inhibitor drug lorlatinib. About half of the resistance are caused by alteration in ALK proteins for earlier ALK TKI drugs and near one-third of loratinib resistant cases are caused by compound mutations without current effective treatment strategy in clinic. Novel strategies are in great need to overcome drug resistance. Lately, two novel strategies have been developed and attracted great attentions for their potentials to overcome drug resistance problems: (1) developed small compact macrocyclic ALK kinase inhibitors and (2) developed ALK targeted proteolysis-targeting chimera (PROTAC) drugs. The macrocyclic molecules are small and compact in size, brain barrier permeable, and highly potent against lorlatinib-resistant compound mutations. Developed ALK targeted PROTAC molecules could degrade oncogenic ALK driver proteins. Some showed superiority in killing ALK positive cancer cells and inhibiting the growth of cells expressing G1202R resistant ALK proteins comparing to inhibitor drugs. The update on these two treatment strategies was reviewed.

A Rotavirus Virus-Like Particle Confined Palladium Nanoreactor and Its Immobilization on Graphene Oxide for Catalysis.

ABSTRACT: In this work, a new viral protein cage based nanoreactor was successfully constructed via encapsulating Tween 80 stabilized palladium nanoparticles (NPs) into rotavirus capsid VP2 virus-like particles (i.e. Pd@VP2). The effects of stabilizers including CTAB, SDS, Tween 80 and PVP on controlling the particle size of Pd NPs were investigated. They were further immobilized on graphene oxide (i.e. Pd@VP2/GO) by a simple mixing method. Some characterizations including FT-IR and XPS were conducted to study adsorption mode of Pd@VP2 on GO sheets. Their catalytic performance was estimated in the reduction of 4-nitrophenol (4-NP). Results showed that Tween 80 stabilized Pd NPs with the molar ratio of Pd to Tween 80 at 1:0.1 possessed the smallest size and the best stability as well. They were encapsulated into viral protein cages (mean size 49 ± 0.26 nm) to assemble confined nanoreactors, most of which contained 1-2 Pd NPs (mean size 8.15 ± 0.26 nm). As-prepared Pd@VP2 indicated an enhanced activity (apparent reaction rate constant k app = (3.74 ± 0.10) × 10-3 s-1) for the reduction of 4-NP in comparison to non-confined Pd-Tween80 colloid (k app = (2.20 ± 0.06) × 10-3 s-1). It was logically due to confinement effects of Pd@VP2 including high dispersion of Pd NPs and high effective concentration of substrates in confined space. Pd@VP2 were further immobilized on GO surface through C-N bond. Pd@VP2/GO exhibited good reusability after recycling for four runs, confirming the strong anchoring effects of GO on Pd@VP2.

Strain difference of DNA-binding activity of NF-kappaB and cytokine gene expression in spleen dendritic cells of Lewis and Fischer rats.

To investigate the mechanisms of different responses to inflammatory stimuli between Lewis and Fischer rats, the DNA-binding activity of the nuclear factor kappa B (NF-kappaB) and cytokine production of spleen dendritic cells (SDC) in Lewis and Fischer rats after peptidoglycan-polysaccharide (PG-PS) treatment were determined. The results show that the DNA-binding activities of NF-kappaB in SDC were higher in Lewis rats than in Fischer rats. Furthermore, in Lewis rats, the increase in NF-kappaB DNA-binding activities was dose-dependent. However, there is no significant change in SDC of Fischer rats. In Lewis rats, the levels of IL-2 and IL-4 were decreased along with the increase of the concentration of PG-PS while TNF-alpha was increased. However, there was no obvious change of cytokine expression in Fischer rats in the presence of PG-PS. In conclusion, these findings indicate that the differences in the DNA-binding activity of NF-kappaB and cytokine production might mediate strain-specific differences of susceptibility to chronic inflammatory stimuli in Lewis and Fischer rats.

Anti-tumor effect of volatile oil from Houttuynia cordata Thunb. on HepG2 cells and HepG2 tumor-bearing mice.

The aim of this paper is to study the anti-tumor mechanism of volatile oil from Houttuynia cordata Thunb. (sodium new houttuyfonate, SNH). In vitro, SNH exhibited a concentration-dependent cytotoxic effect against four human cancer lines (HepG2, A2780, MCF-7, SKOV-3). SNH treatment with different concentrations induced HepG2 cells to exhibit varying degrees of morphological changes in apoptotic features, such as round shape, cell shrinkage and formation of apoptotic body. It was observed that SNH caused the decrease in Bcl-2 mRNA expression and triggered the apoptosis of HepG2 cells. Wound healing assay and RT-PCR results showed that the decrease in the expression level of MMP9 and VEGF was observed in HepG2 cells after treatment with SNH for 48 h, suggesting that the extracellular matrix pathway degradation was involved in the HepG2 cells migration. Moreover, we got an insight into the binding mode of SNH into the MMP9 active site through 3D pharmacophore models. Docking study and molecular dynamics (MD) simulation analysis sheds light on that SNH was completely embedded into the MMP9 active site and formed hydrogen bonds with key catalytic residues of MMP9, including Ala191, His190, Ala189 and Glu227. The prediction of SNH binding interaction energies in the MMP9 was almost in good agreement with the original inhibitor EN140. In vivo experiments, both SNH and cyclophosphamide significantly reduced tumor weights and their tumor inhibitory rates were 50.78% and 82.61% respectively. This study demonstrated that SNH was an apoptosis inducer in HepG2 cells. SNH has four possible functions, that it could induce apoptosis by mitochondria pathway in HepG2 cells, inhibit the tumor growth, regulate Bcl-2 family mRNA expression and effectively subdue migration of hepatocellular carcinoma cells by decreasing the expression of MMP9 and VEGF. Therefore, SNH might be a potential candidate drug for the treatment of hepatocellular carcinoma, which could provide a reference for further clinical research.

Effects of 17beta-estradiol on the maturation, nuclear factor kappa B p65 and functions of murine spleen CD11c-positive dendritic cells.

Physiological gender differences in immune capabilities are now well recognized and suggest that sex steroid hormones such as estrogens may be involved in the regulation of the immunocompetence. In this paper, CD11c-positive murine spleen dendritic cells (SDCs) were treated with various concentrations of 17beta-estradiol (E2) for 24h. The viability, phenotype, nuclear factor kappa B p65 (NF-kappaBp65), endocytosis, stimulatory capacity and cytokine expression were analyzed. Our results showed that E2 increased the viability and MHC-II expression but decreased nuclear NF-kappaBp65 level and endocytosis of SDCs. E2 also increased the stimulatory capacity of SDCs from low-dose group but decreased it from middle- and high-dose ones. In addition, E2 increased the intracellular expression of IL-6 and IL-10 in SDCs, but no obvious change appeared in IL-12 and TNF-alpha. These data suggested that E2 might influence the immune responses by changing the viability, maturation, NF-kappaBp65, endocytosis, stimulatory capacity and cytokine expression of SDCs.

Prolactin modulates the functions of murine spleen CD11c-positive dendritic cells.

Prolactin (PRL), an anterior pituitary polypeptide hormone, has been shown to have a role in the immunomodulation. Some reports have shown the importance of PRL in activating lymphocytes and macrophages. To further investigate the effect of PRL on the immune system in vitro, murine spleen CD11c-positive dendritic cells (SDCs) were treated with various concentrations of PRL for 24 h, then their viability, phenotype, nuclear factor kappa B p65 (NF-kappaBp65), endocytosis, stimulatory capacity, and cytokine expression were analyzed. The results showed that PRL increased the viability and stimulatory capacity of SDCs, up-regulated the expressions of MHC-11 and CD40 while decreased the level of CD54 on SDCs. Furthermore, PRL decreased the level of NF-kappaBp65 and the endocytosis of SDCs. In addition, PRL increased the expressions of IL-6, IL-10, IL-12 and TNF-alpha in SDCs. These data suggested that PRL might regulate the physiological and pathological immune responses by changing the viability, phenotype, NF-kappaBp65, endocytosis, stimulatory capacity, and cytokine expression of SDCs.

Progesterone is involved in the maturation of murine spleen CD11c-positive dendritic cells.

Progesterone (Prog), a female sex steroid hormone, not only plays an important role in the female mammary pregnancy but also influences the immune response. In the present study, murine spleen CD11c-positive dendritic cells (SDCs) were treated with various concentrations of Prog for 24 h, and their viability, phenotype, nuclear factor kappa B P65 (NF-kappaB P65), endocytosis, stimulatory capacity, and cytokine expression were analyzed. The results showed that Prog increased the expressions of MHC-II and CD40, stimulatory capacity and intracellular levels of IL-6 and IL-10, while decreased the expressions of CD54 and IL-12, endocytosis and nuclear level of NF-kappaB P65 of SDCs. These data suggested that Prog may promote the maturation of SDCs and enhance their ability to interact with T cells so as to change the course of autoimmune diseases.

Different characters of spleen OX-62 positive dendritic cells between Fischer and Lewis rats.

The phenotype, DNA-binding activities of NF-kappaB, cytokine production, endocytosis and stimulatory capacity of spleen OX-62-positive dendritc cells (SDCs) from Fischer rats were compared with those from Lewis rats. Results showed that the expressions of CD11b, MHC-II, CD8, CD45RA, CD54 and CD86 on SDCs were significantly higher in Fischer than those in Lewis rats. The levels of IL-2, IL-4, IL-10 and IFN-gamma in SDCs from Fischer rats were distinctly higher than those from Lewis. Both stimulatory capacity and DNA-binding activities of NF-kappaB in SDCs were all lower in Fischer than those in Lewis rats. These differences may partly contribute to rat strain-specificity in susceptibility to chronic inflammatory stimuli.

17beta-estradiol regulates the numbers, endocytosis, stimulative capacity and IL-10 secretion of mouse spleen dendritic cells.

The 17beta-estradiol (17beta-E2) is a steroid sex hormone that has a profound influence on the immune cells in inducing the apoptosis of both T and B lymphocytes. In this study, mouse spleen dendritic cells (SDCs) were treated with 17beta-E2 and the numbers, endocytosis, stimulative capacity and cytokine production of SDCs were analysed. The results showed that 17beta-E2 reduced the proliferation and stimulative capacity of SDCs and increased the endocytosis of SDCs in a dose-dependent pattern. 17beta-E2 up-regulated IL-10 mRNA level in SDCs in a dose-dependent manner except for the 24 h time point. These data suggest that 17beta-E2 may regulate the physiological and pathological immune response by reducing the number and stimulation of SDCs, increasing their endocytosis and IL-10 mRNA expression at the same time.

Dehydroepiandrosterone induces apoptosis of thymocyte through Fas/Fas-L pathway.

Dehydroepiandrosterone (DHEA), the most plentiful steroid hormone, has been convincingly known to have many biological effects and diverse influence in various types of cells, tissues and organs. The effects of DHEA on the humoral and cellular immune response are widely tested, but it is unclear whether DHEA itself serves as an activator of immune function and the literature pertaining to the in vitro effects of DHEA remains contested. In the present paper, the effects of DHEA on the thymocytes in vitro were studied. The results showed that DHEA could enhance the expression of Fas and Fas-L and induce thymocyte apoptosis. This suggests that dehydroepiandrosterone may induce the apoptosis of thymocyte through Fas/Fas-L pathway.

Beneficial effects of wheat gluten hydrolysate to extend lifespan and induce stress resistance in nematode Caenorhabditis elegans.

Previous studies have showed that wheat gluten hydrolysate (WGH) has the anti-oxidative property. In the present study, we examined the possible safety property of WGH and the beneficial effects of WGH to extend lifespan and induce stress resistance using nematode Caenorhabditis elegans as the in vivo assay system. We found that WGH at concentrations of 0.1-1 mg/mL did not cause lethality, influence development, alter locomotion behavior and brood size, and induce significant intestinal autofluorescence and reactive oxygen species (ROS) production in young adults. Treatment with 0.1-1 mg/mL of WGH significantly extended lifespans of nematodes under the normal conditions. Moreover, WGH treatment significantly inhibited the induction of intestinal autofluorescence and suppressed the decrease in locomotion behavior during the aging process of nematodes. Furthermore, pre-treatment with 1 mg/mL of WGH significantly suppressed the adverse effects caused by heat-stress or oxidative stress on nematodes as indicated by the alterations of both lifespan and intestinal ROS production. Therefore, WGH treatment is relatively safe and has beneficial effects on nematodes under both the normal conditions and the stress conditions.

Phenotype and functions of spleen dendritic cells in RICK-knockout mice.

RICK (receptor-interacting caspase-like apoptosis-regulatory kinase), a protein kinase, promotes nuclear factor kappa B and caspase activation. Herein, in order to further learn the immune role of RICK, its gene in mice was knocked out. Then the phenotype, cytokine, endocytosis and stimulatory capacity of spleen dendritic cells (SDCs) from RICK(-) (knockout) and RICK(+) (wild type) mice were analyzed. Our results showed that the levels of I-Ad, CD11b, CD80 on SDCs from RICK(-) mice were higher while the levels of CD8alpha, CD40, CD45R were lower compared with those from RICK(+) mice; The intracellular levels of IL-4, IL-10, IL-12, IFN-gamma, and TNF-alpha in SDCs from RICK(-) mice were higher than those from RICK(+) mice; The endocytosis and stimulatory capacities of SDCs from RICK(-) mice were higher and lower than those from RICK(+) mice respectively. These data suggested that RICK had a profound influence on the maturation and functions of murine SDCs and subsequently regulated the organ immune responses.