31 research outputs found
Prolonged drought regulates the silage quality of maize (Zea mays L.): Alterations in fermentation microecology
Prolonged drought stress caused by global warming poses a tremendous challenge to silage production of maize. Drought during maize growth and development resulted in altered micro-environment for silage fermentation. How fermentation of silage maize responds to moisture scales remains uncharted territory. In this research, Maize water control trials were conducted and the silage quality and microbial community of drought-affected maize were determined. The results showed that drought stress significantly reduced the dry matter but increased root-to-shoot ratio, soluble sugar and malonaldehyde content in maize. Before fermentation, the crude protein, crude ash and acid detergent fiber contents were significantly increased but the ether extract content was decreased under drought. The crude protein and acid detergent fiber were significantly decreased in the drought affected group after fermentation. Furthermore, water stress at maize maturity stage greatly reduced the number of total bacteria in silage fermentation but increased the proportion of the lactobacillus and lactic acid content of silage. Drought stress alters the microbial ecosystem of the fermentation process and reconstitutes the diversity of the bacterial community and its metabolites. This study provides a theoretical basis for the study of changes in silage fermentation as affected by abiotic stresses
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
Optimization of Steam Distillation Process for Volatile Oils from <i>Forsythia suspensa</i> and <i>Lonicera japonica</i> according to the Concept of Quality by Design
In this study, the process of steam distillation to collect volatile oils from Forsythia suspensa (F. suspensa) and Lonicera japonica (L. japonica) was optimized according to the concept of quality by design. First, the liquid/material ratio, distillation time, and collection temperature were identified as critical process parameters by a review of the literature and single-factor experiments. Then, a Box–Behnken design was used to study the quantitative relationship between the three process parameters, two raw material properties, and the yield of volatile oil. A mathematical model was established with an R2 value exceeding 0.90. Furthermore, the design space of the volatile oil yield was calculated by a probability-based method. The results of a verification experiment showed that the model was accurate and the design space was reliable. A total of 16 chemical constituents were identified in the volatile oil from mixtures of F. suspensa and L. japonica. The content of β-pinene was the highest (54.75%), and the composition was similar to that of the volatile oil of F. suspensa. The results showed that when F. suspensa and L. japonica were distilled together, the main contribution to the volatile oil was from F. suspensa. The volatile oil yield from the combination of F. suspensa and L. japonica was not higher than that from L. japonica
Photoluminescence behavior and thermal stability of Eu-doped SiAlON thin films prepared by RF magnetron co-sputtering of SiAlON and Eu 2
Analysis of Volatile Components and Antibacterial Activity of Silver Wormwood Essential Oils from Different Habitats by E-Nose Combined with GC-MS
Electronic nose (E-nose) combined with gas chromatography–mass spectrometry (GC-MS) was used to analyze the volatile components of silver wormwood from different habitats, and the antibacterial activity of essential oils was also studied, to provide a scientific basis for quality control of silver wormwood and rational utilization of their essential oils. In this study, the total content of essential oils in silver wormwood was determined by steam distillation; the volatile components were conducted in an overall analysis by E-nose combined with chemometrics; the volatile components were analyzed and identified by GC-MS; and two G-negative bacteria and one Gram-positive bacteria were used as test bacteria to determine the antibacterial activity of the essential oils from silver wormwood. The results showed that principal component analysis (PCA) and linear discriminant analysis (LDA) of E-nose could distinguish the essential oils of silver wormwood from different habitats, and the odor difference of essential oils was obvious. A total of 87 volatile components were identified by GC-MS, and there were significant differences in components and contents in silver wormwood from different habitats; PCA and hierarchical cluster analysis (HCA) could effectively distinguish silver wormwood from different habitats. The essential oils from silver wormwood from different habitats all had a certain inhibitory effect on Bacillus subtilis, Staphylococcus aureus, and Escherichia coli. Therefore, the combination of E-nose and GC-MS could quickly distinguish silver wormwood from different habitats and provide a reference for quality control, drug selection, and comprehensive utilization of silver wormwood
Accumulation of glycolipids in wheat grain and their role in hardness during grain development
Grain hardness is an important parameter for wheat quality. To understand the role of glycolipids in the formation of grain hardness, the glycolipid contents in wholegrain wheat flour and the starch granule surfaces of oven-dried and freeze-dried hard and soft wheat grain were analyzed. Changes in endosperm structure and amyloplast membrane integrity during grain development were also examined by electron microscopy. The monogalactosyldigylcerol (MGDG) and digalactosyldigylcerol (DGDG) contents of the starch surface were significantly higher in soft wheat than in hard wheat, regardless of the drying method or developmental stage. Throughout grain development, MGDG content was significantly higher in the starch surface of freeze-dried hard wheat than in the starch surface of oven-dried hard wheat. In contrast, the MGDG content of the starch surface was significantly higher in freeze-dried soft grain at 14 and 35Â days after anthesis. No significant difference was observed in puroindoline protein (PIN) accumulation in wholegrain flour from wheat that was dried using the two methods, whereas PIN accumulation on the starch surface of freeze-dried grain was lower than that on the starch surface of oven-dried grain. The gap between the amyloplast membrane and starch granules was larger in hard wheat than in soft wheat, as shown by transmission electron microscopy. For the same wheat cultivar, this gap was larger for oven-dried than for freeze-dried grain. The content of polar lipids in the starch surface was closely related to grain hardness, and the breakdown of the amyloplast membrane may determine the location of polar lipids on the starch surface. Keywords: Amyloplast membrane, Endosperm microstructure, Grain hardness, Polar lipid, Whea
One-Step High-Temperature Solvothermal Synthesis of TiO<sub>2</sub>/Sulfide Nanocomposite Spheres and Their Solar Visible-Light Applications
A one-step high-temperature hydrated-sulfate assisted
solvothermal
method has been developed to synthesize TiO<sub>2</sub>/sulfide nanocomposite
spheres. Different hybrid spheres of TiO<sub>2</sub>/CdS, TiO<sub>2</sub>/Cu<sub>2</sub>S, TiO<sub>2</sub>/FeS, TiO<sub>2</sub>/Co<sub>9</sub>S<sub>8</sub>, and TiO<sub>2</sub>/ZnS were readily prepared
by exploiting different hydrated sulfate. The hydrated sulfate has
been proved to play multifunctional roles during the synthetic process,
such as spherical template, water supplier, and composition controller.
Nanocrystal CdS can be reduced from CdSO<sub>4</sub> at a high solvothermal
temperature of 350 °C, and the TiO<sub>2</sub>/CdS nanocomposite
spheres prepared by this method exhibit superior visible-light-driven
photocatalytic efficiency because of its effective heterointerface
and high crystallinity
Low-Temperature Aluminum Reduction of Graphene Oxide, Electrical Properties, Surface Wettability, and Energy Storage Applications
Low-temperature aluminum (Al) reduction is first introduced to reduce graphene oxide (GO) at 100–200 °C in a two-zone furnace. The melted Al metal exhibits an excellent deoxygen ability to produce well-crystallized reduced graphene oxide (RGO) papers with a low O/C ratio of 0.058 (Al-RGO), compared with 0.201 in the thermally reduced one (T-RGO). The Al-RGO papers possess outstanding mechanical flexibility and extremely high electrical conductivities (sheet resistance <i>R</i><sub>s</sub> ∼ 1.75 Ω/sq), compared with 20.12 Ω/sq of T-RGO. More interestingly, very nice hydrophobic nature (90.5°) was observed, significantly superior to the reported chemically or thermally reduced papers. These enhanced properties are attributed to the low oxygen content in the RGO papers. During the aluminum reduction, highly active H atoms from H<sub>2</sub>O reacted with melted Al promise an efficient oxygen removal. This method was also applicable to reduce graphene oxide foams, which were used in the GO/SA (stearic acid) composite as a highly thermally conductive reservoir to hold the phase change material for thermal energy storage. The Al-reduced RGO/SnS<sub>2</sub> composites were further used in an anode material of lithium ion batteries possessing a higher specific capacity. Overall, low-temperature Al reduction is an effective method to prepare highly conductive RGO papers and related composites for flexible energy conversion and storage device applications