[Characteristics and Source Apportionment of Volatile Organic Compounds in August in the Chang-Zhu-Tan Urban Area].

Continuous sampling using the tank sampling method were conducted in Changsha, Zhuzhou, and Xiangtan cities from August 18 to 27, 2020, and 106 VOCs species were analyzed using GC-MS analysis. Then, the regional VOCs concentrations, generation potential, and source of VOCs were studied. The results showed that the average φ(VOCs) was (20.5±10.5)×10-9 in the Changsha-Zhuzhou-Xiangtan area, in which OVOCs (33.5%) and alkanes (28.2%) accounted for the highest proportion. The ozone formation potential (OFP) of VOCs was 118.5 µg·m-3, and the contributions of aromatic hydrocarbons, olefin, and OVOCs to OFP were 37.4%, 24.2%, and 23.6%, respectively. The average secondary organic aerosol formation potential (SOAp) of the VOCs was 0.5 µg·m-3, and the contribution of aromatic hydrocarbons to SOAp was 97.0%, among which C8 aromatic hydrocarbons contributed 41.7%. Toluene, m/p-xylene, and o-xylene were the common dominant species that contributed significantly to OFP and SOAp. The characteristic ratio results showed that VOCs in Changsha were relatively influenced by industrial processes and solvent use, whereas Zhuzhou and Xiangtan were more affected by coal and biomass combustion. The PMF results showed that the VOCs mainly came from vehicle exhaust and oil and gas volatilization (27.2%), coal and biomass combustion (23.7%), industrial processes (20.4%), solvent use (17.2%), and natural sources (11.5%) in the Changsha-Zhuzhou-Xiangtan area.

[Inventory and Environmental Impact of VOCs Emission from Anthropogenic Source in Chang-Zhu-Tan Region].

Based on environmental statistical data and emission factor, an anthropogenic volatile organic compounds (VOCs) emission inventory was established for the Chang-Zhu-Tan region, and a grid with spatial resolution of 3 km×3 km was built according to the spatial feature data. Ozone formation potential (OFP) and secondary organic aerosol (SOA) formation potential of anthropogenic sources were also estimated. The results showed that the total anthropogenic VOCs emission was about 113.49 kt in Chang-Zhu-Tan region and the main sources were industrial processes, solvent utilization and vehicles with the VOCs emission of 35.88 kt, 28.72 kt and 22.13 kt, respectively. Paving pitch and architecture wall painting accounted for the majority of the solvent utilization and the building materials industry accounted for 75.34% of VOCs emission from the industrial processes. Liling was the largest contributor compared to the other cities in Chang-Zhu-Tan region, where the VOCs emission from these anthropogenic sources in 2014 was 16.58 kt. The total OFP of these sources was 375.33 kt, in which solvent utilization contributed 27.28% and the O3 generative capacity of biomass burning was the largest. Solvent utilization contributed 35.35% to the total SOA formation potentials and its SOA generative capacity was also the largest. The spatial distribution characteristics revealed that the VOCs emission mostly originated from urban area.

Synthesis of adenosine-imprinted microspheres for the recognition of ADP-ribosylated proteins.

Core-shell structural adenosine-imprinted microspheres were prepared via a two-step procedure. Polystyrene core particles (CP) were firstly prepared via a reversible addition-fragmentation chain transfer (RAFT) polymerization leaving the iniferter on the surface of the cores, then a molecularly imprinted polymer (MIP) shell was synthesized on the surface of the cores by using acrylamide (AAm) as the functional monomer and ethylene glycol dimethacrylate (EGDMA) as the cross-linker. The formation and growth of the MIP layer were seen dependent on the initiator (AIBN), AAm and the polymerization time used within the polymerization. SEM/TEM images showed that the dimensions of the cores and shells were 2µM and 44nm, respectively. The MIP microspheres exhibited a fast rebinding rate within 2h and a maximum adsorption capacity of 177µg per gram for adenosine. The adsorption fitted a Langmuir-Freundlich (LF) isotherm model with a KLF value of 41mL/µg and a qm value of 177µg/g for the MIP microspheres. The values were larger than those for a non-molecularly imprinted polymer (NIP) particles (5mL/µg and 88µg/g) indicating a better adsorption ability towards adenosine. The MIP microspheres showed a good selectivity for adenosine with a higher adsorption (683nmol/g) for adenosine than that (91nmol/g, 24nmol/g and 54nmol/g) for guanosine, cytidine and uridine respectively. Further experiment proved that the adenosine-imprinted polymer microspheres also had a good selectivity for ADP-ribosylated proteins that the MIP could extract the ADP-ribosylated proteins from the cell extract samples.

[Anthropogenic Ammonia Emission Inventory and Its Spatial Distribution in Chang-Zhu-Tan Region].

Based on the best available activity data and emission factors, an anthropogenic emission inventory of NH3 was established for the Chang-Zhu-Tan region with spatial resolution of 3 km x 3 km. The results showed that the total quantity of NH3 discharged from anthropogenic sources in the Chang-Zhu-Tan region was 7.27 x 10(4) t, and the average intensity of NH3 emission was 2. 59 t x km(-2). The livestock and poultry industry, and the farmland ecosystem, were the major contribution sources of the anthropogenic NH3 emissions, accounting for 58. 60% and 29.73%, respectively. As for NH3 emission from the livestock and poultry industry, the major contributors were beef, laying hen and pork pig, accounting for 26.26%, 21.40% and 18.43%, respectively. In the Chang-Zhu-Tan region, the quantities of NH3 emissions from Ningxiang county, Xiangtan county and Liuyang city were larger than those of the other districts, accounting for 17. 49%, 12. 82% and 12.02%, respectively. The intensities of NH3 emission from Shifeng and Yuetang districts were larger than those from other districts, reaching up to 9.14 t x km(-2) and 5.01 t x km(-2), respectively. The spatial distribution characteristics revealed that the NH3 emission mostly originated from large point sources.

HMGA1 is a new target of miR-195 involving isoprenaline-induced cardiomyocyte hypertrophy.

Emerging data have shown that microRNAs (miRNAs) have important functions in the processes of cardiac hypertrophy and heart failure that occur during the postnatal period. Cardiac overexpression of miR-195 results in pathological cardiac growth and heart failure in transgenic mice. In the present study, we analyzed the roles of miR-195 in cardiomyocyte hypertrophy and found that miR-195 was greatly upregulated during isoprenaline-induced cardiomyocyte hypertrophy. By using mRNA microarray and molecular approach, we identified a novel putative target of miR-195 called high-mobility group A1 (HMGA1). Total mRNA microarray showed that HMGA1 was downregulated in primary cardiomyocytes that overexpressed miR-195. Using luciferase activity assay, we demonstrated that miR-195 interacts with the 3'-untranslated region of HMGA1 mRNA. Moreover, we showed that miR-195 in primary cardiomyocytes downregulates the expression of HMGA1 at the protein level. Taken together, our data demonstrated that miR-195 can negatively regulate a new target, HMGA1, which is involved in cardiomyocyte hypertrophy.

Insulin-like growth factor 1 opposes the effects of C-reactive protein on endothelial cell activation.

Emerging evidence demonstrates that high plasma C-reactive protein (CRP) levels or low plasma insulin-like growth factor 1 (IGF-1) concentrations may be separately associated with the increased risk of coronary artery disease or myocardial infarction. Interestingly, animal model studies and epidemiological investigations indicate that circulating IGF-1 and CRP levels have an inverse correlation. The present study aims to evaluate if IGF-1 can directly oppose the effects of CRP on endothelial cell (EC) activation. We found that IGF-1 rescues endothelial nitric oxide synthase activity and decreases the release of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 from ECs. We also showed that IGF-1 antagonizes the effects of CRP by activating the PI3K/Akt pathway and suppressing the JNK/c-Jun and MAPK p38/ATF2 signaling pathways, rather than inhibiting ERK1/2 activity. These findings provide evidence of the physiopathological mechanisms of endothelial activation and novel insights into the protective properties of IGF-1.

miR-10a restores human mesenchymal stem cell differentiation by repressing KLF4.

miRNAs have recently been shown to play a significant role in human aging. However, data demonstrating the effects of aging-related miRNAs in human mesenchymal stem cells (hMSCs) are limited. We observed that hMSC differentiation decreased with aging. We also identified that miR-10a expression was significantly decreased with age by comparing the miRNA expression of hMSCs derived from young and aged individuals. Therefore, we hypothesized that the downregulation of miR-10a may be associated with the decreased differentiation capability of hMSCs from aged individuals. Lentiviral constructs were used to up- or downregulate miR-10a in young and old hMSCs. Upregulation of miR-10a resulted in increased differentiation to adipogenic, osteogenic, and chondrogenic lineages and in reduced cell senescence. Conversely, downregulation of miR-10a resulted in decreased cell differentiation and increased cell senescence. A chimeric luciferase reporter system was generated, tagged with the full-length 3'-UTR region of KLF4 harboring the seed-matched sequence with or without four nucleotide mutations. These constructs were cotransfected with the miR-10a mimic into cells. The luciferase activity was significantly repressed by the miR-10a mimic, proving the direct binding of miR-10a to the 3'-UTR of KLF4. Direct suppression of KLF4 in aged hMSCs increased cell differentiation and decreased cell senescence. In conclusion, miR-10a restores the differentiation capability of aged hMSCs through repression of KLF4. Aging-related miRNAs may have broad applications in the restoration of cell dysfunction caused by aging.

Detection of B. anthracis spores and vegetative cells with the same monoclonal antibodies.

Bacillus anthracis, the causative agent of anthrax disease, could be used as a biothreat reagent. It is vital to develop a rapid, convenient method to detect B. anthracis. In the current study, three high affinity and specificity monoclonal antibodies (mAbs, designated 8G3, 10C6 and 12F6) have been obtained using fully washed B. anthracis spores as an immunogen. These mAbs, confirmed to direct against EA1 protein, can recognize the surface of B. anthracis spores and intact vegetative cells with high affinity and species-specificity. EA1 has been well known as a major S-layer component of B. anthracis vegetative cells, and it also persistently exists in the spore preparations and bind tightly to the spore surfaces even after rigorous washing. Therefore, these mAbs can be used to build a new and rapid immunoassay for detection of both life forms of B. anthracis, either vegetative cells or spores.

Seeding-induced self-assembling protein nanowires dramatically increase the sensitivity of immunoassays.

Aiming to build a supersensitive and easily operable immunoassay, bifunctional protein nanowires were generated by seeding-induced self-assembling of the yeast amyloid protein Sup35p that genetically fused with protein G and an enzyme (methyl-parathion hydrolase, MPH), respectively. The protein nanowires possessed a high ratio of enzyme molecules to protein G, allowing a dramatic increase of the enzymatic signal when protein G was bound to an antibody target. As a result, a 100-fold enhancement of the sensitivity was obtained when applied in the detection of the Yersinia pestis F1 antigen.