[Characteristics of Ozone Concentration in Shanghai and Its Associated Atmospheric Circulation Background During Summer Half-years from 2006 to 2021].

It is of great importance to scientifically evaluate the impact of weather and climate conditions on the occurrence of O3 pollution in order to improve the accuracy of O3 pollution forecasts， as well as to reasonably control and reduce the adverse effects of O3 pollution. The characteristics of O3 concentration and climate background were analyzed based on daily O3 concentration data， meteorological factors， and NCEP/NCER reanalysis data from 2006 to 2021 in Shanghai. In addition， the differences in atmospheric circulation situations during years with anomalous O3 concentrations were compared and diagnosed from the perspective of climatology. Additionally， the monthly O3 concentration prediction model （seasonal autoregressive integrated moving average with exogenous regressors， SARIMAX） was further established by adding the key meteorological factors. The results indicated that both the whole-year average and summer half-year average O3 concentrations in Shanghai were increasing with fluctuation， and the summer half-year average was much higher than the annual average， up to 36.2%. Furthermore， there was a significant negative correlation between O3 concentration and wind speed （correlation coefficient of -0.826） and a significant positive correlation with the frequency of static wind and the number of days in which the low cloud cover was less than 20% （correlation coefficients of 0.836 and 0.724， respectively）. The monthly mean O3 concentration had a clear periodicity， showing a pattern with a high concentration in the middle period （April to September） and a low concentration at the beginning and end of the periods. High O3 concentration years （2013-2021） were accompanied by more polluted days， lower average wind speed， more small wind （≤1.5 m·s-1） days， more days of low cloud cover of less than 20%， more days of high temperature， higher direct solar radiation， and more sunshine hours. When the location of the stronger West Pacific subtropical high was westward and southward in the summer half-year， Shanghai was influenced by an anomalous westerly wind， which was not conducive to the transportation of clean air from the sea to Shanghai and thus led to the high concentration of O3 pollution. When the long wave radiation emitted from the ground was low in the summer half-year， it was favorable for the increase in ground temperature and caused a high concentration of O3 pollution. Adding direct solar radiation， maximum temperature， and wind speed as exogenous variables to the monthly O3 forecast model could significantly improve the effectiveness of the monthly forecast， with the root mean square error decreasing by 47.7% （from 22 to 11.5） and the correlation coefficient increasing by 11.2% （from 0.819 to 0.911）， which could be applied to the practical prediction of monthly O3 concentration.

Oriented artificial niche provides physical-biochemical stimulations for rapid nerve regeneration.

Skin wound is always accompanied with nerve damage, leading to significant sensory function loss. Currently, the functional matrix material based stem cell transplantation and in situ nerve regeneration are thought to be effective strategies, of which, how to recruit stem cells, retard senescence, and promote neural differentiation has been obstacle to be overcome. However, the therapeutic efficiency of the reported systems has yet to be improved and side effect reduced. Herein, a conduit matrix with three-dimensional ordered porous structures, regular porosity, appropriate mechanical strength, and conductive features was prepared by orienting the freezing technique, which was further filled with neural-directing exosomes to form a neural-stimulating matrix for providing hybrid physical-biochemical stimulations. This neural-stimulating matrix was then compacted with methacrylate gelatin (GelMA) hydrogel thin coat that loaded with chemokines and anti-senescence drugs, forming a multi-functional artificial niche (termed as GCr-CSL) that promotes MSCs recruitment, anti-senescence, and neural differentiation. GCr-CSL was shown to rapidly enhances in situ nerve regeneration in skin wound therapy, and with great potential in promoting sensory function recovery. This study demonstrates proof-of-concept in building a biomimetic niche to organize endogenous MSCs recruitment, differentiation, and functionalization for fast neurological and sensory recovery.

Experimental pathogenicity and comparative genome analysis of high- and low-virulence strains of rabbit-origin Pasteurella multocida.

Pasteurella multocida, the causative pathogen of rabbit pasteurellosis, causes significant economic losses in the commercial rabbit industry. However, the associated pathogenic mechanism of P. multocida remains unclear. The aim of this study is to compare the genomes and pathogenicity of high- and low-virulence strains of P. multocida to advance the current understanding of rabbit pasteurellosis. The high-virulence strain rapidly proliferates in the lung and spleen of infected mice within approximately 9 h, maintaining a high bacterial load until host death. Meanwhile, the low-virulence strain only proliferates in mouse organs for a short time, with the bacterial load beginning to decrease 13 h post-infection. Moreover, the expressions of inflammatory cytokines MCP-1, TNF-α, and IL-1ß are upregulated in all infected mouse lung and spleen tissue, however, the high-virulence strain induced significantly higher expression than the low-virulence strain. Histopathological analysis revealed greater inflammation and tissue lesions in the lung and spleen of mice infected with the high-virulence strain. Two pathogenicity-associated regions unique to the genome of the high-virulence strain harbor approximately 199 genes, including functional genes related to virulence factors, such as lipopolysaccharide biosynthesis, iron acquisition, biosynthesis of outer membrane proteins, and adhesion. These two genomic regions are shared by three previously sequenced, highly virulent P. multocida strains in rabbits. In conclusion, the increased pathogenicity of high-virulence P. multocida may be due to the presence of virulence-associated genes in two unique genomic regions, resulting in strong proliferative activity, significant inflammation, and pathological lesions in the mouse model. These findings provide important insights regarding the pathogenic mechanism underlying rabbit pasteurellosis.

Pathogenicity of the newly emerged Lagovirus europaeus GI.2 strain in China in experimentally infected rabbits.

In April 2020, rabbit hemorrhagic virus type 2 (Lagovirus europaeus GI.2), which causes highly infectious fatal rabbit hemorrhagic disease, was emerged in China. The phylogenetic analyses of the complete genome sequence of GI.2 showed that it belonged to the non-recombinant GI.3/GI.2 genotype. However, the pathogenicity of this GI.2 strain differed from that of early typical GI.2 strains in Europe. To prevent the spread of the new strain in China, its pathogenicity urgently needs to be studied. Thus, viral shedding and distribution as well as clinical symptoms, histopathological changes, and serum cytokines were studied in experimentally GI.2/SC2020-infected rabbit adults and kits. The kit group showed a shorter survival time after the challenge than the adult group did. The mortality rate was higher in the kits (80 %) than in the adults (30 %). Viral RNA could be detected in both nasal and fecal swabs, and the main dissemination route appeared to be the fecal route. Viral RNA rapidly increased in the blood of the adults and kits at 6 h post-infection, indicating that blood viral load testing can be used for early diagnosis. The most affected organs were the liver and spleen, and the lesions were more severe in the kits than in the adults. The liver contained the highest viral RNA levels. Moreover, serum interleukin (IL)-6, IL-8, IL-10, and tumor necrosis factor-alpha levels were increased in the infected rabbits. In conclusion, our findings will help to understand the evolutionary trends and pathogenic characteristics of GI.2 strains in China.

Arabidopsis MED18 Interaction With RNA Pol IV and V Subunit NRPD2a in Transcriptional Regulation of Plant Immune Responses.

Mediator is a conserved multiprotein complex important for transcription by RNA polymerase II (Pol II). Arabidopsis Mediator subunit MED18 regulates flowering, hormone signaling and plant immunity. Here we report that Arabidopsis MED18 interacted with NUCLEAR RNA POLYMERASE D2a (NRPD2a), the second largest subunit of the nuclear Pol IV and V, which function in RNA-directed DNA methylation and epigenetic regulation of gene expression. Mutants for both MED18 and NRPD2a were compromised in resistance to necrotrophic fungal pathogen Botrytis cinerea. Mutants for NRPD1a, the largest subunit of Pol IV, were also compromised in resistance to Botrytis, supporting a critical role of Pol IV and V in plant defense against Botrytis. Increased Botrytis susceptibility of both the med18 and nrpd2a mutants were associated with reduced accumulation of reactive oxygen species, which are known to promote resistance to Botrytis. Both the basal and pathogen-induced levels of salicylic acid and jasmonic acid were also significantly altered in the med18 and nrpd2a mutants. Transcriptome profiling found that MED18 and NRPD2a affected both unique and overlapping sets of genes in a broad spectrum of biological processes and pathways that influence plant-pathogen interaction. The genes altered in expression in the med18 and nrpd2a mutants include disease resistance proteins, salicylic acid and jasmonic acid signaling and responses, which are known to affect resistance to necrotrophic pathogens. The novel interaction between subunits of Mediator and plant-specific RNA polymerases provides a new mechanism for epigenetic regulation of resistance and expression of defense-related genes in plant immunity.

Emergence of rabbit haemorrhagic disease virus 2 in China in 2020.

Rabbit haemorrhagic disease (RHD) is an acute fatal disease caused by the Lagovirus rabbit haemorrhagic disease virus (RHDV), which was first reported in 1984 in China. Strains of two different genotypes (GI.1a and GI.1c) have been detected in China to date. In 2010, a new RHDV variant with a unique genetic and antigenic profile was identified in France, designated RHDV2, which rapidly spread throughout continental Europe and nearby islands. Here, we report the first outbreak of RHD induced by RHDV2 (GI.2) in rabbit farms in the Sichuan province of China. We conducted haemagglutination tests and phylogenetic analysis of the new RHDV isolate SC2020/04, which was identified as a non-haemagglutinating strain belonging to the RHDV2 (GI.2) genogroup. Considering the serious risk of RHDV2 to the Chinese rabbit industry, the circulation of RHDV2 in the population should be carefully monitored in China.

NF-κB and Keap1 Interaction Represses Nrf2-Mediated Antioxidant Response in Rabbit Hemorrhagic Disease Virus Infection.

The rabbit hemorrhagic disease virus (RHDV), which belongs to the family Caliciviridae and the genus Lagovirus, causes lethal fulminant hepatitis in rabbits. RHDV decreases the activity of antioxidant enzymes regulated by Nrf2 in the liver. Antioxidants are important for the maintenance of cellular integrity and cytoprotection. However, the mechanism underlying the regulation of the Nrf2-antioxidant response element (ARE) signaling pathway by RHDV remains unclear. Using isobaric tags for relative and absolute quantification (iTRAQ) technology, the current study demonstrated that RHDV inhibits the induction of ARE-regulated genes and increases the expression of the p50 subunit of the NF-κB transcription factor. We showed that RHDV replication causes a remarkable increase in reactive oxygen species (ROS), which is simultaneously accompanied by a significant decrease in Nrf2. It was found that nuclear translocation of Keap1 plays a key role in the nuclear export of Nrf2, leading to the inhibition of Nrf2 transcriptional activity. The p50 protein partners with Keap1 to form the Keap1-p50/p65 complex, which is involved in the nuclear translocation of Keap1. Moreover, upregulation of Nrf2 protein levels in liver cell nuclei by tert-butylhydroquinone (tBHQ) delayed rabbit deaths due to RHDV infection. Considered together, our findings suggest that RHDV inhibits the Nrf2-dependent antioxidant response via nuclear translocation of Keap1-NF-κB complex and nuclear export of Nrf2 and provide new insight into the importance of oxidative stress during RHDV infection.IMPORTANCE Recent studies have reported that rabbit hemorrhagic disease virus (RHDV) infection reduced Nrf2-related antioxidant function. However, the regulatory mechanisms underlying this process remain unclear. The current study showed that the NF-κB p50 subunit partners with Keap1 to form the Keap1-NF-κB complex, which plays a key role in the inhibition of Nrf2 transcriptional activity. More importantly, upregulated Nrf2 activity delayed the death of RHDV-infected rabbits, strongly indicating the importance of oxidative damage during RHDV infection. These findings may provide novel insights into the pathogenesis of RHDV.

[Characteristics of Aerosol Particulate Concentrations and Their Climate Background in Shanghai During 2007-2016].

We use daily aerosol particulate matter<10 µm (PM10) concentration data from 2006 to 2016 in Shanghai along with meteorological elements (wind and temperature), atmospheric stability, temperature inversion, and upper atmosphere circulation data, to analyze the variation characteristics of the PM10 concentrations and differences of the winter climate background. We establish a multivariate linear stepwise regression equation, and also compare and analyze differences in the upper atmospheric circulation by selecting the years with the highest and lowest PM10 concentrations. The results showed an oscillating downward trend in the annual average concentrations of PM10 in Shanghai, whereas seasonally, PM10 concentrations were relatively high in winter and showed two peaks with a low in between. PM10 concentrations were negatively correlated with the daily average wind speed and the daily mixing layer height at 20:00, and positively correlated with the frequency of northwest wind, the mean daily temperature, and the frequency of stable weathers and thermal inversion at 20:00. When the 500 hPa height field in the northern part of China was a positive anomaly in winter, a warm winter prevailed and led to high PM10 concentrations. When the 500 hPa height field was a negative anomaly, cold air frequently moved southward to result in relatively low temperatures, which caused relatively low PM10 concentrations. When the wind field at 850 hPa was easterly, the wind speed was relatively large and resulted in relatively low PM10 concentrations.

Ferroelectric nanocomposite networks with high energy storage capacitance and low ferroelectric loss by designing a hierarchical interface architecture.

Nanoscale design of nanofillers and interfacial architecture are vital to achieve high-capacity and high-energy-conversion efficiency poly(vinylidene fluoride) [(PVDF)-based] nanocomposite materials for vast potential applications in modern electronic devices and electric power systems. Using traditional methods, the addition of ceramic nanoparticles can only produce one type of interface between the nanoparticles and this matrix, achieving an enhanced dielectric constant and energy density at the expense of the charge-discharge efficiency. Herein, we demonstrate a novel class of cross-linking nanofiller system, poly(vinylidene fluoride-chlorotrifluoroethylene)/γ-methacryloylpropyl trimethoxysilane@BaTiO3 [P(VDF-CTFE)/MPS@BT]. This novel approach can not only provide the interfaces between the nanoparticle and the matrix, but also scale down the size of crystalline domains, which results in producing more additional interfaces between the crystalline and amorphous phases to achieve an improved discharged energy density. Remarkably, the smaller crystalline domains, which were characterized by XRD and FTIR spectroscopy, could be beneficial for improving the dipole switchability from the polar phases to non-polar phases during the charge-discharge cycles, leading to unprecedented charge-discharge efficiency. Furthermore, the addition of MPS@BT NPs can regulate two stages of the discharge rate. The early discharge process can be accelerated, while the following stage is obviously delayed. The simplicity of the hierarchical interfacial engineering method provides a promising path to design ferroelectric polymer nanocomposites for dielectric capacitor applications.

Efficient Water Transport and Solar Steam Generation via Radially, Hierarchically Structured Aerogels.

A nature-inspired water-cycling system, akin to trees, to perform effective water and solar energy management for photosynthesis and transpiration is considered to be a promising strategy to solve water scarcity issues globally. However, challenges remain in terms of the relatively low transport rate, short transport distance, and unsatisfactory extraction efficiency. Herein, enlightened by conifer tracheid construction, an efficient water transport and evaporation system composed of a hierarchical structured aerogel is reported. This architecture with radially aligned channels, micron pores, and molecular meshes is realized by applying a radial ice-template method and in situ cryopolymerization technique. This nature-inspired design benefits the aerogel excellent capillary rise performance, realizing a long-distance (>28 cm at 190 min) and quick (>1 cm at 1 s, >9 cm at 300 s) antigravity water transport on a macroscopic scale, regardless of clean water, seawater, sandy groundwater, or dye-including effluent. Furthermore, an efficient water transpiration and collection is performed by the bilayer-structured aerogel with a carbon heat collector on an aerogel top, demonstrating a solar steam generation rate of 2.0 kg m-2 h-1 with the energy conversion efficiency up to 85.7% under one solar illumination. This biomimetic design with the advantage of water transport and evaporation provides a potential approach to realize water purification, regeneration, and desalination.

Detection of mucoid enteropathy syndrome disease in rabbit farms in East China.

During the past years epizootic outbreaks of mucoid enteropathy syndrome (MES) disease have emerged and spread rapidly in rabbit farms in East China causing great economic losses. To investigate the nature and evolution of the disease, two trials were conducted in an attempt to reproduce the disease and to assess the microbiota cecal profile changes associated with the disease. In the first trial, twenty 6-week-old New Zealand White healthy rabbits were assigned randomly to one of two treatments: 1) Inoculation with 2.0 mL of cecal content (inoculum) from dead rabbits affected with MES; 2) No inoculation or control group. In the second trial, V3 - V4 regions of 16S ribosomal genes from three virulent (MES) and two non-virulent (healthy) cecal samples were amplified and sequenced for microbiota genomic characterization. The mucoid enteropathy syndrome was reproduced using a virulent cecal material (inoculum). The mortality rates for treatments 1 and 2 were 70% and 0%, respectively. Clinical signs and gross lesions of affected rabbits consisted of bloated abdomen, cecal impaction, presence of variable amounts of gelatinous mucus particularly in the colon, mucus excretion and diarrhea of low intensity. The disease that emerged in China is similar to the epizootic rabbit enteropathy (ERE) described in Europe. However, microbiota cecal changes associated with the disease differed from those in ERE. Here, a comprehensive analysis of mucoid enteropathy syndrome disease is presented, which should be carefully monitored.

Three-dimensional graphene biointerface with extremely high sensitivity to single cancer cell monitoring.

We developed a three-dimensional biointerface of graphene-based electrical impedance sensor for metastatic cancer diagnosis at single-cell resolution. Compared with traditional impedance sensor with two-dimensional interface, the graphene biointerface mimiced the topography and somatotype features of cancer cells, achieving more comprehensive and thorough single cell signals in the three-dimensional space. At the nodes of physiological behavior change of single cell, namely cell capture, adhesion, migration and proliferation, the collected electrical signals from graphene biointerface were about two times stronger than those from the two-dimensional gold interface due to the substantial increase in contact area and significant improvement of topographical interaction between cells and graphene electrode. Simultaneous CCD recording and electrical signal extraction from the entrapped single cell on the graphene biointerface enabled to investigate multidimensional cell-electrode interactions and predict cancerous stage and pathology.

Rabbit Hemorrhagic Disease Virus Non-structural Protein 6 Induces Apoptosis in Rabbit Kidney Cells.

Rabbit hemorrhagic disease (RHD) is a highly contagious disease caused by rabbit hemorrhagic disease virus (RHDV). Previous research has shown that RHDV induces apoptosis in numerous cell types, although the molecular mechanisms underlying the apoptosis induced by RHDV are not well understood. One possible factor is non-structural protein 6 (NSP6), a 3C-like protease that plays an important role in processing viral polyprotein precursors into mature non-structural proteins. To fully establish a role for NSP6, the present study examined the effects of ectopic expression of the protein in rabbit (RK13) and human (HeLa and HepG2) cells. We found that NSP6 suppressed cell viability and promoted apoptosis in all three cell types in a dose-dependent manner. We also identified increased caspase-3, -8, and -9 activities in RK13 cell, and an increased Bax to Bcl2 mRNA ratio. Mechanistically, the ability of NSP6 to induce apoptosis was impaired by mutation of the catalytic His27 residue. Our study has shown that RHDV NSP6 can induce apoptosis in host cells and is likely an important contributor to RHDV-induced apoptosis and pathogenesis.

Molecular cloning of the rabbit interleukin 6 promoter: Functional characterization of rabbit hemorrhagic disease virus response elements in RK-13 cells.

Infection with rabbit hemorrhagic disease virus (RHDV) can cause acute liver failure (ALF), leading to severe mortality in rabbits. Inflammatory response, especially the expression of inflammatory cytokines such as interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and IL-6, may play major roles in mediating and amplifying the ALF. Among these cytokines, IL-6 is a multifunctional cytokine with a central role in various physiological inflammatory and immunological processes. In this study, we found that RHDV infection significantly upregulated IL-6 gene expression in vivo. Next, the rabbit IL-6 promoter was cloned and analyzed. Transfection of full-length RHDV cDNA in RK-13 cells upregulated the activity of the IL-6 promoter. A series of 5' deletion constructs demonstrated that AP-1 (activator protein 1), NF-IL6 (nuclear factor interleukin-6), and NF-κB (nuclear factor kappa B) elements were critical for RHDV-induced IL-6 transcription. Besides, the CREB (cAMP-response element binding protein) element may also play an accessory effect on RHDV-induced IL-6 transcription. Collectively, the results elucidate the mechanism of IL-6 induction, and enrich the RHDV pathogenesis in rabbit.

A new variant of rabbit hemorrhagic disease virus G2-like strain isolated in China.

To investigate the genetic variability and evolution of rabbit hemorrhagic disease virus (RHDV) strains in China, VP60 gene sequences of eight new isolates collected from farms with RHD occurrences in China between 2009 and 2014 were analyzed, and compared with the reference sequence of the vaccine strain WF/China/2007. We conducted a comprehensive analysis of the Chinese RHDV strains, including hemagglutination tests, western blot and immunosassays of capsid proteins, and phylogenetic analysis, and identified a new distinct antigenic variant. Specifically, strain HB/2014 collected in North China was identified as a non-hemagglutinating strain, and belongs to the original RHDV (G1-G5) group. The other seven isolates were classified in genogroup G6 (RHDVa), which was widely distributed across China before 2014, and was thought to replace the earlier groups. Antigenic characterization of the VP60 genes revealed a large degree of nucleotide sequence divergence between HB/2014 and the other Chinese strains. However, the current vaccine showed complete cross-protection against HB/2014 challenge in inoculated rabbits. Collectively, these data provide new tools and insight for further understanding the molecular evolution of RHDV in China.

Identification of novel rabbit hemorrhagic disease virus B-cell epitopes and their interaction with host histo-blood group antigens.

Rabbit haemorrhagic disease, caused by rabbit hemorrhagic disease virus (RHDV), results in the death of millions of adult rabbits worldwide, with a mortality rate that exceeds 90%. The sole capsid protein, VP60, is divided into shell (S) and protruding (P) domains, and the more exposed P domain likely contains determinants for cell attachment and antigenic diversity. Nine mAbs against VP60 were screened and identified. To map antigenic epitopes, a set of partially overlapping and consecutive truncated proteins spanning VP60 were expressed. The minimal determinants of the linear B-cell epitopes of VP60 in the P domain, N(326)PISQV(331), D(338)MSFV(342) and K(562)STLVFNL(569), were recognized by one (5H3), four (1B8, 3D11, 4C2 and 4G2) and four mAbs (1D4, 3F7, 5G2 and 6B2), respectively. Sequence alignment showed epitope D(338)MSFV(342) was conserved among all RHDV isolates. Epitopes N(326)PISQV(331) and K(562)STLVFNL(569) were highly conserved among RHDV G1-G6 and variable in RHDV2 strains. Previous studies demonstrated that native viral particles and virus-like particles (VLPs) of RHDV specifically bound to synthetic blood group H type 2 oligosaccharides. We established an oligosaccharide-based assay to analyse the binding of VP60 and epitopes to histo-blood group antigens (HBGAs). Results showed VP60 and its epitopes (aa 326-331 and 338-342) in the P2 subdomain could significantly bind to blood group H type 2. Furthermore, mAbs 1B8 and 5H3 could block RHDV VLP binding to synthetic H type 2. Collectively, these two epitopes might play a key role in the antigenic structure of VP60 and interaction of RHDV and HBGA.

Ultrasonic and Thermal Pretreatments on Anaerobic Digestion of Petrochemical Sludge: Dewaterability and Degradation of PAHs.

Effects of different pretreatment methods on sludge dewaterability and polycyclic aromatic hydrocarbons (PAHs) degradation during petrochemical sludge anaerobic digestion were studied. Results showed that the total biogas production volume in the thermal pretreatment system was 4 and 5 times higher than that in the ultrasound pretreatment and in the control system, and the corresponding volatile solid removal efficiencies reached 28%, 15%, and 8%. Phenanthrene, paranaphthalene, fluoranthene, benzofluoranthene, and benzopyrene removal rates reached 43.3%, 55.5%, 30.6%, 42.9%, and 41.7%, respectively, in the thermal pretreatment system, which were much higher than those in the ultrasound pretreatment and in the control system. Moreover, capillary suction time (CST) of sludge increased after pretreatment, and then reduced after 20 days of anaerobic digestion, indicating that sludge dewaterability was greatly improved after anaerobic digestion. The decrease of protein and polysaccharide in the sludge could improve sludge dewaterability during petrochemical sludge anaerobic digestion. This study suggested that thermal pretreatment might be a promising enhancement method for petrochemical sludge solubilization, thus contributing to degradation of the PAHs, biogas production, and improvement of dewaterability during petrochemical sludge anaerobic digestion.

Compound Chinese herbal medicinal ingredients can enhance immune response and efficacy of RHD vaccine in rabbit.

In order to validate the immune-enhancement efficacy of compound Chinese herbal medicinal ingredients (cCHMIs), made with astragalus polysaccharide (APS), epimedium polysaccharide (EPS), propolis flavone (PF) and ginsenosides (GS), as immune potentiator or vaccine adjuvants for rabbits, the effects of two cCHMIs on rabbit lymphocyte proliferation and IFN-gamma and IL-10 mRNA expression of T lymphocyte in vitro were determined. At the same time, two cCHMIs were injected into 35-day-old rabbits after mixed with rabbit hemorrhagic disease (RHD) vaccine taking aluminum adjuvant and phosphate-buffered saline (PBS) as controls. On days 7, 14, 21, 35 and 49 after the vaccination, the dynamic changes of peripheral lymphocyte proliferation and serum antibody titers of the rabbits were analyzed. On day 63, all rabbits were challenged with RHD virus. The results showed that the two cCHMIs could significantly promote rabbit lymphocyte proliferation and IFN-gamma and IL-10 mRNA expression of T lymphocyte in vitro. In vivo, two cCHMIs could significantly enhance serum antibody titers and lymphocyte proliferation. Their adjuvanticity was slightly superior to aluminum adjuvant. All the rabbits vaccinated with the cCHMIs adjuvant vaccine were protected. These findings confirmed that two cCHMIs possessed better immune-enhancement efficacy and would be used as effective immune adjuvant of RHD vaccine.

Development of an RT-PCR for rabbit hemorrhagic disease virus (RHDV) and the epidemiology of RHDV in three eastern provinces of China.

Reverse transcriptase polymerase chain reaction (RT-PCR) for the diagnosis of rabbit hemorrhagic disease virus (RHDV) was developed by examining sensitivity and specificity. Samples from rabbits infected with rabbit hemorrhagic disease (RHD) were examined to investigate the distribution of the virus in the body. The results showed that the RT-PCR method had good specificity. The sensitivity of the RT-PCR was 1 x 10(4) times higher than that of the hemagglutination assay (HA). RT-PCR was able to detect RHDV in all viscera, but not in feces. In the second part of the study, in order to investigate the prevalence of RHDV, 400 meat samples from the Entry-exit Inspection and Quarantine Bureau and 512 nasal secretion samples from rabbits in three provinces of China were collected and tested by RT-PCR. The results showed significant differences in the prevalence of RHDV in rabbits of different ages, but no significant differences among different provinces and years. Some random isolates were sequenced and compared. The homology of sequences among three new isolates and other isolates ranged between 93.7% and 99.6%. It is recommended that RHD vaccine should be used in China to protect rabbits against RHDV.

Addition of antioxidant from bamboo leaves as an effective way to reduce the formation of acrylamide in fried chicken wings.

The efficiency of antioxidant from bamboo leaves on the reduction of acrylamide during thermal processing and optimization of levels of addition of antioxidant from bamboo leaves applied to fried chicken wings are reported. The authors optimized the method of the addition of antioxidant from bamboo leaves to fried chicken wings and the frying processing parameters, and also compared the relationship between the content of total flavonoids in three extracts (EBL(971), EBL(972) and antioxidant from bamboo leaves) and the extent of the reduction of acrylamide. The acrylamide levels were quantified by a validated liquid chromatography coupled with tandem mass spectrometry detection method and the sensory evaluation was performed in a double-blind manner. The results showed that nearly 57.8 and 59.0% of acrylamide in fried chicken wings were reduced when the antioxidant from bamboo leaves addition ratios were 0.1 and 0.5% (w/w), respectively. The maximum inhibitory rate was achieved when antioxidant from bamboo leaves was chosen as the additive with a total flavonoid content of 32% compared with other two extracts and antioxidant from bamboo leaves mixed with flour was selected as the method of addition. Sensory evaluation results showed that the odour and flavour of fried chicken wings with antioxidant from bamboo leaves treatments had no significant difference compared with normal food matrixes (p > 0.05) when the antioxidant from bamboo leaves addition ratio was <0.5% (w/w). Colour acceptability in the study of sensory evaluation was in good correspondence with colour formation of fried chicken wings in each test group. These results suggest that antioxidant from bamboo leaves could significantly reduce acrylamide formation in fried chicken wings and yet still retain the original flavour and odour of the fried products. This study could be regarded as a pioneer contribution to the reduction of acrylamide in various foods by natural antioxidants.