An Extended SISa Model for Sentiment Contagion

One of the main differences between sentiment and infectious diseases is that the former one has two opposite infectious states: positive (optimistic) and negative (pessimistic), while the latter one has not. In this paper, based on the SISa model, we consider this issue and propose a new model of sentiment contagion called the SOSa-SPSa model. The results of both numerical and agent-based simulations show that our model could explain the process of sentiment contagion better than that of Hill et al. (2010). Further analysis shows that both the numbers of optimistic and pessimistic individuals will increase with the probability of spontaneity or contagion and decrease with the probability of recovery. Potential applications of this model in financial market have also been discussed

Studying Term Structure of SHIBOR with the Two-Factor Vasicek Model

With the development of the Chinese interest rate market, SHIBOR is playing an increasingly important role. Based on principal component analysing SHIBOR, a two-factor Vasicek model is established to portray the change in SHIBOR with different terms. And parameters are estimated by using the Kalman filter. The model is also used to fit and forecast SHIBOR with different terms. The results show that two-factor Vasicek model fits SHIBOR well, especially for SHIBOR in terms of three months or more

Improved corrosion resistance of magnesium alloy prepared by selective laser melting through T4 heat treatment for biomedical applications

Selective laser melting (SLM) technology has broad prospects for developing magnesium alloys in structural and biomedical applications. The effects of T4 heat treatment on microstructure, mechanical properties and corrosion resistance of as-built AZ91D alloy were investigated. The results showed that after T4 treatment, β-Mg17Al12 phases distributed around the matrix changed from networks to diffuse dots and then disappeared at 420 °C for 1 h. The tensile strength and hardness of AZ91D alloy decreased after T4 treatment. In addition, electrochemical and immersion experiments showed that the corrosion resistance was greatly improved after solution. Compared with the as-built AZ91D alloy, the solution-treat sample exhibited higher corrosion resistance in Hanks' solution, and its corrosion current density was reduced by 70%, hydrogen evolution rate by 57%, and corrosion rate by about 78% in the weightless experiment. In this study, after solution-treat, the corrosion resistance of as-built AZ91D can be significantly improved while meeting the mechanical requirement of degradable alloys, and has great potential for biomedical applications

Sarm1/Myd88-5 Regulates Neuronal Intrinsic Immune Response to Traumatic Axonal Injuries

Summary: Traumatic injuries can trigger inflammatory reactions, leading to profound neuropathological consequences. However, the immune capacity of neurons, distinct from that of immune cells or glial cells, in response to traumatic insults remains to be fully characterized. In this study, we demonstrate that neurons can detect, cell autonomously, distant axonal damage, resulting in rapid production of a specific collection of cytokines and chemokines. This neuronal immune response appears spatially and temporally separated from injury-induced axon degeneration. We then identify through the genetic screen that this immune response is regulated by TIR-domain adaptor Sarm1/Myd88-5. We further show that Sarm1 functions through the downstream Jnk-c-Jun signal, and blockage of this Sarm1-Jnk-c-Jun pathway effectively abolishes the recruitment of immune cells to injury-afflicted neural tissues. We therefore uncover the key function of the Sarm1 signaling pathway, independent of its known role in axon degeneration, in the neuronal intrinsic immune response to traumatic axonal injuries. : Wang et al. report that neurons possess an intrinsic immune capacity in response to traumatic axonal injuries, which is spatially and temporally separated from injury-induced axon degeneration. This neuronal immune response is regulated by TIR-domain adaptor protein Sarm1/Myd88-5 and its downstream Jnk-c-Jun signal. Keywords: neuronal intrinsic immune response, traumatic injuries, neuroinflammation, Sarm

Effects of exogenous salicylic acid on accumulation of camptothecin and gene expression in Camptotheca acuminata Decne

Camptotheca acuminata Decne (Nyssaceae) is major natural source of camptothecin, an anticancer drug widely used for clinic therapy. Previous works have shown that many plant hormones/elicitors could regulate camptothecin biosynthesis, but few reports have examined sustanable effects of these plant hormones on plants for producing camptothecin. In this work, seedlings obtained from in vitro rapid propagation were used for investigating sustainable effect of Salicylic acid (SA) on transplanted C. acuminata tissues, especially leaves, for camptothecin biosynthesis. Our results indicate that exogenous SA could continuously induce the expression of iridoids pathway genes in C. acuminata leaves for promoting camptothecin production. After transplanted to soil for 180 days, high expression of iridoids pathway genes still could be observed in bioactive young leaves. In C. acuminata, iridoids pathway genes are expressed at very low levels or not detectable in old leaves, which lead to inefficient production of camptothecin with leaf development. Interestingly, the expression of these genes could be clearly detected in old leaves of transplanted C. acuminata pretreated with 10 ÂľM of SA during in vitro rapid propagation phase, which indicates particular function of SA for sustainable effect on maintaining relative high expression levels of iridoids pathway genes for camptothecin biosynthesis.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Bicarbonate ringer’s solution could improve the intraoperative acid-base equilibrium and reduce hepatocellular enzyme levels after deceased donor liver transplantation: a randomized controlled study

Abstract Background Bicarbonate Ringer’s (BR) solution is a direct liver and kidney metabolism-independent HCO3 − buffering system. We hypothesized that BR solution would be more effective in improving acid-base equilibrium and more conducive to better liver function than Acetate Ringer’s (AR) solution in conventional orthotopic liver transplantation (OLT) patients. Methods Sixty-nine adult patients underwent OLT. Patients in the bicarbonate and acetate groups received BR solution or AR solution as infused crystalloids and graft washing solution, respectively. The primary outcome was the effect on pH and base excess (BE) levels. The secondary outcome measures were the incidence and volume of intraoperative 5% sodium bicarbonate infusion and laboratory indicates of liver and kidney function. Results The pH and absolute BE values changed significantly during the anhepatic phase and immediately after transplanted liver reperfusion in the bicarbonate group compared with the acetate group (all P < 0.05). The incidence and volume of 5% sodium bicarbonate infusion were lower in the bicarbonate group than in the acetate group (all P < 0.05). The aspartate transaminase (AST) level at 7 postoperative days and the creatine level at 30 postoperative days were significantly higher in the acetate group than in the bicarbonate group (all P < 0.05). Conclusion Compared with AR solution, BR solution was associated with improved intraoperative acid-base balance and potentially protected early postoperative liver graft function and reduced late-postoperative renal injury

Self-assisted membrane-penetrating helical polypeptides mediate anti-inflammatory RNAi against myocardial ischemic reperfusion (IR) injury

Anti-inflammatory RNA interference (RNAi) provides a promising paradigm for the treatment of myocardial ischemia reperfusion (IR) injury. To overcome the membrane barriers against intracardial siRNA delivery, various guanidinated helical polypeptides with potent and aromaticity-assisted membrane activities were herein developed and used for the delivery of siRNA against RAGE (siRAGE), a critical regulator of the pro-inflammatory cascade. Aromatic modification of the polypeptide led to notably enhanced trans-membrane siRNA delivery efficiencies, and more importantly, allowed more siRNA cargoes to get internalized via non-endocytosis, an effective pathway toward gene transfection. Subsequently, benzyl-modified polypeptide (P-Ben) was identified as the top-performing material with the highest RAGE silencing efficiency yet lowest cytotoxicity in H9C2 cells. Intracardial injection of the P-Ben/siRAGE polyplexes at 150 mu g siRNA per kg led to remarkable RAGE knockdown by similar to 85%, thereby attenuating the inflammatory cytokine release and reducing the cardiomyocyte apoptosis as well as myocardium fibrosis to recover the cardiac function after IR injury. This study therefore provides an effective strategy for the design of membrane-penetrating gene delivery materials, and may provide a promising addition to the anti-inflammatory treatment of myocardial IR injury

Neutrophil-mediated delivery of pixantrone-loaded liposomes decorated with poly(sialic acid)–octadecylamine conjugate for lung cancer treatment

Poly(sialic acid) (PSA) is a natural hydrophilic biodegradable and non-immunogenic biopolymer, receptors for its monomer are expressed on peripheral blood neutrophils (PBNs), which plays important roles in the progression and invasion of tumors. A poly(sialic acid)–octadecylamine conjugate (PSA–ODA) was synthesized and then anchor it on the surface of liposomal pixantrone (Pix-PSL), to achieve an improved anticancer effect. The liposomes were prepared using a remote loading method via a pH gradient, and then assessed for particle size, zeta potential encapsulation efficiency, in vitro release, and in vitro cytotoxicity. Simultaneously, in vitro and in vivo cellular uptake studies confirmed that PSA-decorated liposomes provided an enhanced accumulation of liposomes in PBNs. An in vivo study presented that the anti-tumor activity of Pix-PSL was superior to that of other Pix formulations, probably due to the efficient targeting of PBNs by Pix-PSL, after which PBN containing Pix-PSL (Pix-PSL/PBNs) in the blood circulation are recruited by the tumor microenvironment. These findings suggest that PSA-decorated liposomal Pix may provide a neutrophil-mediated drug delivery system (DDS) for the eradication of tumors, which represents a promising approach for the tumor targeting of chemotherapeutic treatments