新型解毒剂T对异噁草松造成玉米药害的缓解作用

通过测定植株叶绿素含量与荧光光谱特征动态变化，分析除草剂异FDB8草松和解毒剂T 对玉米植株的生理作用。随着除草剂浓度升高，叶绿素浓度下降，单位叶绿素荧光强度比不 断上升，而解毒剂T可缓解上述伤害。     

不同种群螟黄赤眼蜂和松毛虫赤眼蜂的抗药性测定

分别测定了螟黄赤眼蜂和松毛虫赤眼蜂各5个不同地理种群对灭多威、溴氰菊酯、辛硫磷的室内抗性水平。结果表明,不同地区或不同生态条件下的赤眼蜂种群具有抗药性差异。螟黄赤眼蜂的敏感种群为采自吉林省长春市的农场种群,与之比较,其他4个种群对灭多威的LC50的变化范围为其1.93～6.72倍,对溴氰菊酯的LC50为其5.35～39.08倍,对辛硫磷的LC50为其3.49～29.76倍;松毛虫赤眼蜂的敏感种群为采自黑龙江省尚志市的亚布力南种群,与之比较,其他各个种群对灭多威的LC50的变化范围为其9.52～70.66倍,对溴氰菊酯的LC50为其73.12～288.16倍,对辛硫磷的LC50的变化范围为11.84～50.38倍。     

牛病毒性腹泻病毒NS3蛋白的生物信息学分析及多表位筛选

本研究旨在对牛病毒性腹泻病毒（BVDV）NS3蛋白进行生物信息学分析及T细胞和B细胞表位的筛选。从GenBank数据库中找到NS3蛋白的氨基酸序列，用Expasy ProtParam在线服务器分析所得序列理化性质。使用TMHMM Server分析跨膜结构域，使用DNAStar软件预测NS3蛋白的二级结构，为了更准确地预测蛋白质的二级结构，使用SOPMA分析软件进行了二次预测。使用Phyre2在线服务器预测NS3蛋白的三级结构，并用Raswin软件标出各个元素所处的位置。使用4种预测软件（BCPREDS、ABCpred、BepiPred和SVMTriP）分析NS3蛋白的线性B细胞表位，使用NetMHCⅡpan预测CD4⁺ T细胞表位，使用NetBoLApan和IEDB预测CD8⁺ T细胞表位，将所得到的结果进行T细胞和B细胞表位筛选。结果表明，NS3蛋白质由683个氨基酸组成，分子质量为75 ku，理论等电点（pI）为8.31，化学式为C₃₃₄₇H₅₃₄₆N₉₁₆O₁₀₀₉S₂₈，不稳定系数为35.93，平均亲水性（GRAVY）值为-0.267，表明NS3为稳定性亲水蛋白质。TMHMM结果显示，NS3蛋白不具有跨膜结构域。SOPMA结果表明，在NS3蛋白的二级结构中，α-螺旋、β-折叠、β-转角和无规则卷曲分别约占30.75%、22.55%、8.35%和38.35%，用DNAStar软件分别标出了α-螺旋、β-折叠、β-转角和无规则卷曲所处的位置。运用4种不同的B细胞预测软件筛选出8个线性表位：12-16、289-298、349-360、394-407、421-432、489-498、515-525和665-679位氨基酸。用NetMHCⅡpan筛选出4个T细胞表位：248-262、315-320、400-414和482-496位氨基酸。本研究为BVDV NS3蛋白优势抗原的筛选提供了理论依据。     

GIP/GIPR经Akt-TCF4-GIPR正反馈增强GIP效应

旨在从GIP/GIPR下游的Akt和PKA信号通路中筛选出调控GIPR表达的调控因子，并解析GIPR的表达调控机制。本研究以小鼠胰岛瘤细胞系Min6为试验材料，在Akt、PKA信号通路阻断的条件下，通过Western blot筛选出与GIPR表达相关的转录因子T细胞因子4（TCF4）；利用双荧光素酶报告系统确定TCF4对GIPR表达调控的影响，再通过敲除或过表达TCF4进一步验证两者之间的调控关系；采用CCK8法检测TCF4介导的促增殖作用，ELISA检测胰岛素分泌能力。结果显示，GIP可激活Akt磷酸化，并促进GIPR表达；在GIP激活及Akt、PKA信号通路阻断时，GIPR蛋白表达趋势与TCF4始终一致；TCF4可与GIPR核心启动子区结合，进而调控其表达；TCF4过表达时，GIPR的mRNA和蛋白表达上调，并促进β细胞增殖及胰岛素分泌；干扰TCF4显著降低GIP作用下GIPR的mRNA和蛋白表达，抑制β细胞增殖。综上，GIP结合GIPR后，经Akt信号通路上调TCF4进而增强GIPR表达，形成正反馈加强GIP信号，提高β细胞增殖和胰岛素分泌的功能，维持血糖稳态。因此，在胰岛素抵抗阻断Akt及上游信号通路时，经转录因子TCF4增强GIPR表达可作为改善胰岛β细胞功能障碍的靶点。     

转基因玉米T25数字PCR方法的建立与验证

转基因安全管理和标识制度的实施需要标准化的检测方法和转基因检测标准物质，标准物质是获得准确、可靠、可比检测结果的保证。转基因玉米T25为我国批准进口用作加工原料的转基因植物。为加强对T25的监管，以T25基体标准物质为研究对象，建立数字PCR方法，并选择8家实验室，采用数字PCR联合定值测定。结果表明，T25/Adh1二重数字PCR系统具有良好的扩增特异性。初始模板量在100～10 000拷贝·μL-1之间可获得稳定、可靠的检测结果。通过多实验室协同定值说明T25/Adh1二重数字PCR方法准确、可靠。T25基体标准物质的量值为1.001 2，相对不确定度为0.001 6。研究表明建立的T25/Adh1二重数字PCR方法可以用于转基因玉米T25的定量检测，为转基因成分定量检测提供了物质基础和技术保证。     

An engineered anti-idiotypic antibody-derived killer peptide (KP) early activates swine inflammatory monocytes,CD3+CD16+ natural killer T cells and CD4+CD8α+ double positive CD8β+ cytotoxic T lymphocytes associated with TNF-α and IFN-γ secretion

This study evaluated the early modulation of the phenotype and cytokine secretion in swine immune cells treated with an engineered killer peptide (KP) based on an anti-idiotypic antibody functionally mimicking a yeast killer toxin. The influence of KP on specific immunity was investigated using porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) as ex vivo antigens. Peripheral blood mononuclear cells (PBMC) from healthy pigs were stimulated with KP and with a scramble peptide for 20 min, 1, 4 and 20 h or kept unstimulated. The cells were analyzed using flow cytometry and ELISA. The same time-periods were used for KP pre-incubation/co-incubation to determine the effect on virus-recalled interferon-gamma (IFN-γ) secreting cell (SC) frequencies and single cell IFN-γ productivity using ELISPOT.KP induced an early dose-dependent shift to pro-inflammatory CD172α⁺CD14^+high monocytes and an increase of CD3⁺CD16⁺ natural killer (NK) T cells. KP triggered CD8α and CD8β expression on classical CD4⁻CD8αβ⁺ cytotoxic T lymphocytes (CTL) and double positive (DP) CD4⁺CD8α⁺ Th memory cells (CD4⁺CD8α^+low CD8β^+low). A fraction of DP cells also expressed high levels of CD8α. The two identified DP CD4⁺CD8α^+high CD8β^+low/+high CTL subsets were associated with tumor necrosis factor alpha (TNF-α) and IFN-γ secretion. KP markedly boosted the reactivity and cross-reactivity of PRRSV type-1- and PCV2b-specific IFN-γ SC. The results indicate the efficacy of KP in stimulating Th1-biased immunomodulation and support studies of KP as an immunomodulator or vaccine adjuvant.     

干旱胁迫及复水对硬质早熟禾细胞内渗透调节物质的影响

为了研究细胞渗透调节物质与早熟禾抗旱机理的关系,在现有的试验条件下,以黑龙江硬质早熟禾作为供试材料,采用连续干旱处理的方法,与国外引进品种印第安酋长和统治者进行比较,研究3个早熟禾细胞内渗透调节物质与抗旱性相适应的关系。结果表明:3个草种体内的可溶性糖及脯氨酸含量均升高,复水后降低;可溶性蛋白呈下降趋势,复水后呈上升趋势。三者表现出的积累速度和恢复能力为:硬质早熟禾印第安酋长统治者。     

Chimeric Antigen receptor-T (CAR-T) cells targeting Epithelial cell adhesion molecule (EpCAM) can inhibit tumor growth in ovarian cancer mouse model

Ovarian cancer (OC) is one of the most lethal solid tumors with poor prognosis. In 2017, two chimeric antigen receptor-T (CAR-T) cell drugs were approved by the U.S. Food and Drug Administration (FDA), and continuously optimized CAR-T cells therapy might be the novel hope for OC patient. EpCAM are known to be over-expressed in OC cells and could be targeted by CAR-T cells. However, the feasibility of using EpCAM-CAR-T cells to treat OC still needs to be verified. We engineered the 3rd-generation EpCAM-CAR containing a single-chain variable fragment (scFv) EpCAM-scFv that targeting EpCAM, a CD8 transmembrane domain, the costimulatory domains from both CD28 and 4-1BB, and activating domain CD3ζ and then transduced the CAR into T-cells via lentivirus. In addition, the cytotoxicity and cytokine releasing ability of the EpCAM-CAR-T cells against OC cell SKOV3 were verified in vitro. The in vivo data also showed that EpCAM-CAR-T cells significantly reduced the tumor size in OC xenograft mouse models. The anti-tumor activity of EpCAM-CAR-T cells against OC in vitro and in vivo indicated that the CAR-T might provide a promising therapeutic approach to OC.     

牛肉加热过程中水分迁移规律研究

采用100℃隔水加热方式加热牛肉28 min,每隔7 min采集一次样品,利用LF-NMR技术初步探讨牛肉加热过程中水分迁移规律。结果表明:随着加热时间的延长,牛肉蒸煮损失呈现上升趋势,剪切力不断增大,核磁数据显示牛肉内部水分状态组成变化显著,T2弛豫时间逐渐变短,不易流动水T22占比逐渐减少,自由水T23占比逐渐增多,且随着加热时间的延长,不易流动水和自由水很难在T2弛豫谱上分开,峰宽变大趋势明显,核磁成像结果显示加热会降低牛肉内部的水分含量。相关性分析结果表明:T21与牛肉的蒸煮损失呈显著正相关,T22与牛肉的蒸煮损失、剪切力呈显著负相关,T22峰面积占比与T2b、牛肉的蒸煮损失、剪切力呈显著负相关。由此得出加热处理对牛肉内部的水分分布和质构特性产生显著影响,同时两者之间存在相关性。     

Barley response to salt stress at varied levels of phosphorus

Increasing plant phosphorus (P) supply can increase or decrease salt tolerance of many plants. Barley (Hordeum vulgare L., cv. ACSAD 176) was grown in nutrient solution under controlled conditions to determine effects of P level on detrimental effects of sodium chloride (NaCl). Increasing level of P improved tolerance of barley to NaCl. At 3, 30, and 60 μM P, the NaCl concentrations to reduce shoot dry matter (DM) by 50% were 158, 193, and 260 mM, respectively. Increased NaCl levels reduced shoot P concentrations. Plants grown with NaCl had higher Internal P requirements. When NaCl in solution was 10, 150, and 300 mM, the corresponding concentrations of P in shoots required to obtain 50% DM were 1.6, 4.2, and 4.7 mg‐g^‐1 dry weight, respectively. Increasing solution P level from 3 to 60 μM P decreased sodium (Na) and increased potassium (K) concentrations in shoots. Accumulation of mineral ions for osmotic adjustment and restriction of Na accumulation in shoots was involved in P enhancement of salt tolerance of barley.