Heat Stress Upregulates the Expression of TLR4 and Its Alternative Splicing Variant in Bama Miniature Pigs

Alternative splicing is a cellular mechanism in eukaryotes that results in considerable diversity ofgene products. It plays an important role in several diseases and cellular signal regulation. Heat stress is a major factor that induces immunosuppression in pigs. Little is known about the correlation between alternative splicing and heat stress in pigs. Therefore, this study aimed to clone, sequence and quantify the alternative splicing variant of toll-like receptor 4 （TLR4） in Bama miniature pigs （Sus scrofa domestica） following exposure to heat stress. The results showed that the second exon of TLR4 was spliced and 167 bp shorter in the alternative splicing variant, and the protein was putatively identified as a type of truncated membrane protein consisting of extramembrane, transmembrane and intramembrane regions lacking a signal peptide. Further, it was not a non- classical secretory protein. Five potential reference genes were screened for their potential as reliable standards to quantify the expression of TLR4 alternative spliced variants by real-time quantitative reverse-transcriptase polymerase chain reaction （qRT-PCR）. The stability of these reference genes was ranked using the geNorm and NormFinder programs, and ribosomal protein L4 （RPL4） and TATA box-binding protein （TBP） were found to be the two genes showing the most stable expression in the in vitro cultured peripheral blood mononuclear ceils （PBMCs） during heat shock. The mRNA level of the TLR4 gene （both classical and spliced） in stressed pigs increased significantly （P〈0.05）. Further, the expression levels of the alternative spliced variant of TLR4 （TLR4-ASV） showed a 2-3 folds increase in heat-stressed PBMCs as compared to control pigs. The results of the present study suggested that heat shock might modulate the host immune response by regulating the expressions of TLR4 and its alternative splicing variant.

Regime shift in Lake Dianchi(China) during the last 50 years

Lake Dianchi has undergone accelerated alternations resulting from human activities during the last 50 years, and provides an exceptional example for the study of regime shift in a shallow lake. Focusing on regime shift, we systematically studied and analysed alternations of key components of its ecosystem, including water parameters, phytoplankton and zooplankton biomass, macrophyte composition and fish populations. We found that the shifting course of Lake Dianchi went through three major phases, corresponding to three distinct states: Phase I clean, stable state during the 1950 s; Phase II transitional state during the 1970 s–1980 s; and phase III stable, turbid state since 1993. We analysed all data and samples, identifying the threshold concentrations at which regime shift occurred: total nitrogen(TN) and phosphorus(TP) reaching 1.2 mg/L and 0.13 mg/L, respectively. Results from this study strongly suggest that the increasing input of external nutrients, reclaiming land from the lake and foreign fish invasion were major inducements to the accelerated shift of Lake Dianchi to its turbid, stable state. These findings provide valuable guidelines for potential efforts to reverse this unnatural process in Lake Dianchi. The restoration may need to:(1) thoroughly and accurately identify pollution sources to control and reduce excessive external nutrients flowing into the lake;(2) return reclaimed land to the lake and recover the littoral zone to its natural state to facilitate increased restoration of macrophytes; and(3) strategically adjust fish populations by reducing benthivorous and filter-feeding fish populations that prey on zooplankton, while enlarging zooplankton populations to control phytoplankton biomass.

Syngas Fuel Combustion in Re-circulating Vortex Combustor

This paper presents results on the combustion of syngas fuel in re-circulating vortex combustor. The combustion stability is achieved through the use of cavities in which recirculation zones of hot products generated by the direct injection of fuel and air are created and acting as a continuous source of ignition for the incoming main fuel-air stream. CFD （computational fluid dynamics） analysis was performed in this study to test the combustion performance and emissions from the vortex trapped combustor using synthetic gas or syngas fuel produced from the gasification process. The flame temperature, the flow field and species concentrations inside the vortex trapped combustor were obtained. Several syngas fuels with different fuel compositions （H2, CO, CH4, CO2, N2 and H20） and lower heating values were tested in this study. The changes on the flame temperature and species concentrations inside the combustor, the emissions of NOx, CO, CO2 at the exit of the combustor, the combustor efficiency and the total pressure drop for syngas fuels are presented in this paper. The effect of H2/CO ratio and the mass fraction of each constituent of syngas fuels and hydrogen-methane fuel mixtures on the combustion and emissions performances were investigated.

Field Evaluation of Alternative Testing Strategies for the Detection of HIV Infection in Beijing

To identify a cost-efficient altemative antibody testing strategy for screening and confirmation of HIV infection by rapid simple tests （RSTs） and enzyme-linked immunosorbent assays （ELISAs）. Methods Four RSTs （RST1, RST2, RST3, and RST4 ） and five ELISAs （ELISA1, ELISA2, ELISA3, ELISA4, and ELISA5） were evaluated in two phases by using banked and serum specimens prospectively collected at regional hospitals and voluntary counseling and testing （VCT） centers in Beijing. A total of 200 banked serum specimens were included in the first phase, including 62 HIV-positive, 127 HIV-negative and 11 indeterminate specimens. All specimens were tested by four RSTs and five ELISAs respectively. The second phase involved prospective testing of 389 routine specimens, including 92 HIV-positive, 287 HIV-negative, and 10 indeterminate specimens. All the specimens were tested by two RSTs （RST2 and RST4） and three ELISAs （ELISA1, ELISA3, and ELISA4）, which were selected for their respective excellent sensitivity and/or specificity. Westem blot （WB） was used as a gold standard for confirming the reactivity of all the specimens. Results Sensitivity, specificity, and efficacy were calculated for each assay in two phases. In the first phase, four assays （ELISA4, RST2, RST3, and RST4） had a specificity of 100%. For the determination of efficacy, ELISA4, RST2, and RST4 were selected in the second phase. ELISA1 and ELISA3 which have a sensitivity of 95.9% and 93.2% respectively also entered this phase. In the second phase, all the five assays （ELISA1, ELISA3, ELISA4, RST2, and RST4） had a sensitivity and specifity of over 90%. ELISA1 had a sensitivity of 99% and ELISA4 a specificity of 99%. Conclusion The sensitivity ELISA1 and the specificit of ELISA4 are comparable to ELISA/WB standard strategy. Application of this alternative testing strategy provides a cost-effective method for determining HIV prevalence in Beijing.

Power Generation from Municipal Solid Waste Plastics

Generation of electrical energy from imported fossil fuels is subject to the price fluctuations of the global marketplace and, thus, constitutes a major expense in its distribution to the end users. Even with the current low prices of fuel, residents and businesses in the United States pay a significant price for their utilities, if not higher than most other countries in the world. Emissions from the evaporation and combustion of these traditional fossil fuels contribute to a range of environmental and health problems, causing poor air quality, and emitting greenhouse gases that contribute to global warming. Alternative fuel created from domestic sources has been proposed as a solution to these problems and much alternative energy are being developed based on solar, wind, biomass, hydropower, fuel cell, geothermal, etc. A new alternative hydrocarbon fuel which is produced from waste plastics can be used with compatble power plants and generators appliances to produce electricity that can be supplied into homes, businesses, power grids and other sectors.

Predicting ecological regime shift under climate change： New modelling techniques and potential of molecular-based approaches

Ecological regime shift is the rapid transition from one stable community structure to another, often ecologically infe- rior, stable community. Such regime shifts are especially common in shallow marine communities, such as the transition of kelp forests to algal turfs that harbour far lower biodiversity. Stable regimes in communities are a result of balanced interactions be- tween species, and predicting new regimes therefore requires an evaluation of new species interactions, as well as the resilience of the ＇stable＇ position. While computational optimisation techniques can predict new potential regimes, predicting the most likely community state of the various options produced is currently educated guess work. In this study we integrate a stable regime op- timisation approach with a Bayesian network used to infer prior knowledge of the likely stress of climate change （or, in practice, any other disturbance） on each component species of a representative rocky shore community model. Combining the results, by calculating the product of the match between resilient computational predictions and the posterior probabilities of the Bayesian network, gives a refined set of model predictors, and demonstrates the use of the process in determining community changes, as might occur through processes such as climate change. To inform Bayesian priors, we conduct a review of molecular approaches applied to the analysis of the transcriptome of rocky shore organisms, and show how such an approach could be linked to meas- ureable stress variables in the field. Hence species-specific microarrays could be designed as biomarkers of in situ stress, and used to inform predictive modelling approaches such as those described here.

Effects of splice sites on the intron retention in histamine H_3 receptors from rats and mice

In the alternative splicing, intron retention, of histamine H3 receptors in rats and mice, the short transcript isoforms that are excised alternatively spliced introns are easily detected in a very low level in rats and are undetectable in mice using the regular PCR protocol. The retained introns have common 5＇ splice site and different 3＇ splice sites. The detailed mechanism for the special alternative splicing remains largely unclear. In this study, we developed a minigene splicing system to recapitulate natural alternative splicing of the receptors and investigated the effects of 5＇ and 3＇ splice sites on intron retention in HeLa cells. Mutating weak 5＇ and 3＇ splice sites of the alternatively spliced introns toward the canonical consensus sequences promoted the splicing of the corresponding introns in rat and mouse minigenes. The effect of splice site strength was context-dependent and much more sigiaificant for the 3＇ splice site of the longer alternative intron than for the 3＇ splice site of the shorter alternative intron and the common 5＇ splice sites; it was also more significant in the rat minigene than in the mouse minigene. Mutating the 3＇ splice site of the longer alternative intron resulted in almost complete splicing of the intron and made the corresponding isoform to become the nearly exclusive transcript in the rat minigene.