激素对奶牛乳腺上皮细胞乳脂肪合成的调控作用

乳脂肪是高质量的天然脂肪，其可为人类提供营养和能量，在各种膳食脂肪和油类中，是最容易被消化吸收的。乳脂肪是在乳腺中由从头合成或外源摄取的脂肪酸与甘油酯化形成的一种脂类物质，其含量的高低关系着牛奶品质的优劣和乳制品的加工特性。在奶牛的泌乳周期中，乳腺泌乳功能受多种因素影响，其中内分泌腺分泌的多种激素对奶牛乳腺上皮细胞（BMECs）乳脂的合成具有积极的调控作用。综上所述，作者介绍了氢化可的松、催乳素、胰岛素和生长激素4种泌乳相关激素对BMECs乳脂肪合成的调控机理，即从乳脂合成适宜的激素添加量、激素对乳脂球形态的影响方面初步阐释其调控作用，并从乳脂合成的关键酶及转录因子、激素对乳脂合成相关基因表达量方面深入阐释其作用机理，旨在为研究泌乳相关激素对奶牛乳腺内乳脂肪合成的调控机理提供参考。     

类器官的研究进展及应用前景

类器官（organoids）来源于自组织和自我更新的干细胞，是利用干细胞的自组织特性进行体外3D培养后形成的细胞团，与来源器官密切相关，再现了来源器官的三维细胞结构，并为探索来源器官的发病机制提供了新的模型。类器官系统是由自分泌、旁分泌或邻分泌信号调节下的细胞，或者外源性添加的细胞外基质（extracellular matrix，ECM）底物、小分子和生长因子等衍生而来，这些因素的相互作用创造了一个动态的环境，指导干细胞的自我更新和分化，以及细胞在类器官中的自我组装。诱导多能干细胞（induced pluripotent stem cells，iPSC）重编程方法结合3D类器官工具，使患者来源的类器官作为动物模型和人类临床试验之间的桥梁，是对细胞研究和在体试验的补充。在研究来源器官发育、生物学和病理生理学方面，类器官不仅是一种比传统细胞培养更具生理相关性的体外模型，而且还是再生医学和个性化医学领域中的新模型，有望成为研究营养素、药物、毒物及毒素等的作用机制及药物的筛选、再生医学等领域的重要模型。总之，类器官技术的发展增强了人们对器官和组织生理生化功能的认知。作者对肠、脑、肺脏、肝脏、子宫、卵巢等类器官培养和应用的研究进展进行综述，以期为类器官相关科研及应用提供参考。     

大白菜游离小孢子培养技术高效体系的研究

以大白菜吉红82、#534DH 群体及#438 群体为试材，研究了利用细胞破碎仪机械提取小孢子与人工挤压提取小孢子对大白菜游离小孢子活力及提取量的影响。结果表明：机械提取替代人工挤压可在短时间内同时提取多份样品，并可快速调整小孢子的培养浓度。收集40 个适期花蕾于5 mL 离心管内，3 000 r·min-1 破碎10 s，将提取的小孢子定容于25 mL NLN-13 培养基，可确保小孢子浓度在适宜培养范围内，并成功诱导胚胎发生。     

Transplantation of human amnion epithelial cells improves learning and memory function in Alzheimer's disease-like pathology rat model

AIM: To observe the treatment effect and its immune regulation of human amnion epithelial cells (hAECs) on Alzheimer's disease (AD)-like pathology rat model. METHODS: The hAECs were isolated from amnion with trypsin digestion, and the phenotype of hAECs was analyzed by flow cytometry. SD rats (n=48) were randomly divided into sham control group, model group, medium group and hAECs group. AD-like pathology rat model was induced by bilateral intraventricular injection of lipopolysaccharide (LPS). hAECs (5×10⁵) were injected into the hippocampus of the AD-like pathology rats. At 2 weeks after transplantation, the animals were tested by Morris water maze to observe the function of learning and memory. The pathological change of the brain was observed by HE staining. The expression of amyloid β-protein 42(Aβ42) and Tau protein and the level of acetylcholine (ACh) in the injury brain were determined by immunohistochemistry. The survival and differentiation of hAECs in the hippocampus were measured by immunofluorescent technique. The percentages of lymphocyte subsets in the peripheral blood mononuclear cells were analyzed by flow cytometry. The contents of serum cytokines were detected by cytometric bead array. RESULTS: Compared with model group and medium group, hAECs group showed shortened escape latency (P<0.01), increased frequency of going through the platform (P<0.05), reduced loss of hippocampal neurons, decreased expression of Tau protein and Aβ42 in the hippocampus (P<0.05), increased ACh level in the hippocampus (P<0.05), decreased percentages of Th1 and Th17 subsets, increased percentages of Th2 and Treg cells (P<0.05), decreased concentrations of IFN-γ and IL-2 in the serum, and increased concentration of IL-4(P<0.05). CONCLUSION: hAECs improve the cognitive learning and memory function and alleviate pathologic damage of hippocampus through immune regulation in AD-like pathology rats.     

EZH2-mediated regulation of NF-κB target gene expression in gastric cancer

AIM: To explore the mechanism by which over-expression of enhancer of zeste homolog 2 (EZH2) in a panel of gastric cancer cell lines is involved in tumorigenesis of gastric cancer. METHODS: Real-time PCR and Western blot were employed to examine the mRNA and protein levels of EZH2, respectively. MTS assay, cell migration and soft agar assay were performed to investigate the role of EZH2 in the regulation of stomach cancer behaviors. The effect of EZH2 on NF-κB target gene expression was determined by Luciferase reporter and real-time PCR. Co-immunoprecipitation was used to analyze the interaction of EZH2 and p65 in HEK293T cells. RESULTS: The expression levels of EZH2 were significantly increased in the gastric cancer cells compared with normal gastric epithelial cells. Pharmacological inhibition by DZNep or knockdown of EZH2 significantly compromised AGS and SNU-16 cell activity, cell migration and anchorage-independent cell growth. Moreover, siRNA knockdown of EZH2 impaired NF-κB downstream targets, such as IL-8, CXCL5 and CCL20. In addition, the interaction of EZH2 and p65 was detected. CONCLUSION: EZH2 mediates the growth of gastric cancer cells through the regulation of NF-κB downstream gene expression.     

Fucoidan and Cancer: A Multifunctional Molecule with Anti-Tumor Potential

There is a wide variety of cancer types yet, all share some common cellular and molecular behaviors. Most of the chemotherapeutic agents used in cancer treatment are designed to target common deregulated mechanisms within cancer cells. Many healthy tissues are also affected by the cytotoxic effects of these chemical agents. Fucoidan, a natural component of brown seaweed, has anti-cancer activity against various cancer types by targeting key apoptotic molecules. It also has beneficial effects as it can protect against toxicity associated with chemotherapeutic agents and radiation. Thus the synergistic effect of fucoidan with current anti-cancer agents is of considerable interest. This review discusses the mechanisms by which fucoidan retards tumor development, eradicates tumor cells and synergizes with anti-cancer chemotherapeutic agents. Challenges to the development of fucoidan as an anti-cancer agent will also be discussed.     

Diagnosis and Treatment of Anaplastic Mammary Carcinoma in a Sugar Glider (Petaurus breviceps)

A 9-year-old female sugar glider (Petaurus breviceps) was evaluated for a tissue mass near the marsupium. Ultrasonography identified a vascular mass originating from the right mammary gland. Fine-needle aspiration was suggestive of a malignant neoplasm. The glider was anesthetized and the tumor was removed, and this was followed by strontium-90 plesiotherapy to the tumor bed in an attempt to decrease local recurrence. Histopathology revealed an anaplastic mammary carcinoma. The glider was euthanized less than 14 days after the procedure owing to self-mutilation behavior of unknown etiology. This report is the first to describe the clinical presentation, diagnostics, therapeutics, and treatment response for a sugar glider with mammary neoplasia.     

马链球菌兽疫亚种烯醇化酶对小鼠肺泡巨噬细胞吞噬功能的影响

旨在研究马链球菌兽疫亚种（Streptococcus equi ssp.zooepidemicus，SEZ）烯醇化酶（enolase，Eno）对小鼠肺泡巨噬细胞（RAW264.7）吞噬能力的影响。通过构建原核表达质粒获得重组烯醇化酶（rEno），采用台盼蓝活细胞计数法，判定在不同处理浓度和时间下rEno蛋白对RAW264.7细胞的细胞毒性。将rEno蛋白与RAW264.7细胞共孵育后，用SEZ作用于细胞并检测细胞吞菌数量，判断RAW264.7细胞对SEZ的吞噬活性。进一步通过活细胞稳定同位素标记技术（SILAC）和蛋白质谱分析技术（LC-MS/MS），筛选到RAW264.7细胞中可能与SEZ Eno存在相互作用的候选蛋白。结果发现，10 μg·mL^-1 rEno蛋白处理对RAW264.7细胞有明显的细胞毒性，且10 μg·mL^-1 rEno蛋白处理RAW264.7细胞2和4 h可显著抑制其对SEZ的吞噬作用（P<0.01、P<0.05）。初步筛选到RAW264.7细胞中动力蛋白激活蛋白亚单位蛋白（dynactin subunit protein 2，Dctn）、整合素α-M蛋白（integrin alpha-M）等17种可能与Eno发生互作的蛋白。本研究获得了rEno重组表达蛋白，发现rEno可减少RAW264.7细胞对SEZ的吞噬，互作蛋白的初步筛选也为进一步揭示Eno在SEZ抗吞噬中的作用机制奠定了基础。