四川平须舞虻属Platypalpus三新种（双翅目：舞虻科）

平须舞虻属Platypalpus Macquart是舞虻科中最大的属之一,已知550余种分布世界各地.四川以前已知8种.本文记述四川平须舞虻属3新种:短芒平须舞虻Platypalpus breviarista sp.nov.,微距平须舞虻Platypalpus minor sp.nov.和亚丁平须舞虻Platypalpus yadinganus sp.nov,均属于长角平须舞虻种团Platypalpus longicornis species group,并编制了四川平须舞虻属分种检索表.     

Comparative analysis of carbohydrate binding properties of Sambucus nigra lectins and ribosome-inactivating proteins

In the past three decades a lot of research has been done on the extended family of carbohydrate-binding proteins from Sambucus nigra, including several so-called type 2 RIPs as well as hololectins. Although all these proteins have been studied for their carbohydrate-binding properties using hapten inhibition assays, detailed carbohydrate specificity studies have only been performed for a few Sambucus proteins. In particular SNA-I, has been studied extensively. Because of its unique binding characteristics this lectin was developed as an important tool in glycoconjugate research to detect sialic acid containing glycoconjugates. At present much less information is available with respect to the detailed carbohydrate binding specificity of other S. nigra lectins and RIPs, and as a consequence their applications remain limited. In this paper we report a comparative analysis of several lectins from S. nigra using the glycan microarray technology. Ultimately a better understanding of the ligands for each lectin can contribute to new/more applications for these lectins in glycoconjugate research. Furthermore, the data from glycan microarray analyses combined with the previously obtained sequence information can help to explain how evolution within a single lectin family eventually yielded a set of carbohydrate-binding proteins with a very broad specificity range.     

渭北旱塬保护性耕作对冬小麦-春玉米轮作田蓄水保墒效果和产量的影响

通过2007—2010年田间定位试验,研究了平衡施肥、常规施肥和无肥(或低肥)条件下,免耕、深松和翻耕处理对渭北旱塬冬小麦-春玉米轮作田土壤贮水量、作物产量、水分利用效率(WUE)和纯收益的影响.结果表明:休闲期免耕处理蓄水保墒效果最好,深松次之,翻耕最差;轮作田生育期内免耕和深松处理0~200 cm平均土壤贮水量分别较翻耕提高6.7%和1.9%;各施肥条件下作物产量、WUE和纯收益均以深松处理最高,且以平衡施肥深松处理表现最好,2007—2008年冬小麦、2009年春玉米、2009—2010年冬小麦产量分别为6909、9689、5589 kg.hm-2,WUE分别为18.5、25.2、23.0 kg.hm-2.mm-1,纯收益分别为5034、5045、7098元.hm-2.因此,平衡施肥与深松组合处理的蓄水保墒和增产增收效果最好,是渭北旱塬冬小麦-春玉米轮作田较适合的施肥耕作模式.     

番石榴4个品种叶和幼果的生物活性和酚类成分研究

为提高番石榴（Psidium guajava）副产物的综合利用率,测定了‘珍珠’、‘水蜜’、‘红宝石’和‘西瓜’4个品种叶和幼果提取物中的酚类与黄酮含量,并分析了其与清除DPPH·、ABTS⁺、HO·自由基能力和α-葡萄糖苷酶抑制活性的相关性,并用超高效液相色谱-串联质谱法（UPLC-MS/MS）分析了提取物的酚类成分。结果表明,4个番石榴品种叶的酚类和黄酮含量、清除自由基能力、α-葡萄糖苷酶抑制活性均显著高于幼果,‘珍珠’叶的酚类含量最高,生物活性最强。酚类、黄酮含量与清除自由基能力呈极显著正相关（P<0.01）,与α-葡萄糖苷酶抑制活性呈显著正相关（P<0.05）。UPLC-MS/MS鉴定结果表明,4个品种叶酚类含量较高的均为槲皮素-3-O-葡萄糖苷、金丝桃苷、鞣花酸和杨梅苷,除鞣花酸外大部分存在于叶的酚类成分也存在于幼果中,且含量显著高于幼果。因此,4个品种中,‘珍珠’叶是开发天然抗氧化剂和α-葡萄糖苷酶抑制剂的优良资源。     

低镁胁迫对低温下黄瓜幼苗光合特性和抗氧化系统的影响

以‘津优3号’黄瓜幼苗为试材,以Hoagland全营养液处理为对照(CK),研究低镁(30％Mg)胁迫对低温(昼/夜温度12℃/8℃)下黄瓜幼苗光合特性和抗氧化系统的影响.结果表明:低温下30％Mg处理黄瓜幼苗叶片Mg含量显著低于CK,而根中Mg含量与CK差异不显著.随着低温胁迫时间的延长,黄瓜幼苗叶片的叶绿素含量、净光合速率(Pn)、气孔导度(gs)和羧化效率(CE)逐渐降低,胞间CO2浓度(Ci)趋于升高.与CK相比,低温下30％ Mg处理叶片叶绿素含量、Pn、gs和CE显著降低,C-变化不大,叶绿体膜损伤严重,叶绿体数、基粒数和片层数较少,淀粉粒数增加,淀粉粒较长,丙二醛(MDA)含量升高,而超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)和谷胱甘肽还原酶(GR)活性降低.可见,低温下镁运输受阻引起的缺镁是叶片失绿的主要原因;低温引起Pn降低的主要原因是非气孔限制,低镁胁迫会加大低温对黄瓜Pn的影响,而由此引起的Pn降低的主要原因是气孔限制.     

Characterization of Chrysanthemum ClSOC1-1 and ClSOC1-2, homologous genes of SOC1

The MADS-box gene SOC1/TM3 (SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1/ Tomato MADS-box gene 3) is a main integrator in the Arabidopsis flowering pathway; its structure and function are highly conserved in many plant species. SOC1-like genes have been isolated in chrysanthemum, one of the most well-known ornamental plants, but it has not been well characterized thus far. We isolated and characterized ClSOC1-1 and ClSOC1-2, two putative orthologs of Arabidopsis SOC1, from the wild diploid chrysanthemum, Chrysanthemum lavandulifolium, to investigate the regulatory mechanisms of flowering time control in chrysanthemum. Expression analysis indicated that ClSOC1-1 and ClSOC1-2 were expressed in all examined organs/tissues (leaves, shoot apices, petioles, stems and roots) with different expression levels, and with high expression in the shoot apices and leaves during the early stage of floral transition. The expression levels of ClSOC1-1 and ClSOC1-2 in the shoot apices increased at different developmental stages with the highest expression levels after 7 days of short-day treatment. Overexpression of ClSOC1-1 and ClSOC1-2 in wild-type Arabidopsis resulted in early flowering, which was coupled with the upregulation of one of the flowering promoter genes LEAFY. Our results suggested that the ClSOC1-1 and ClSOC1-2 genes play an evolutionarily conserved role in promoting flowering in Chrysanthemum lavandulifolium and could serve as a vital target for the genetic manipulation of flowering time in the chrysanthemum.     

Low-serum culture system improves the adipogenic ability of visceral adipose tissue-derived stromal cells

In obese adipose tissue, infiltrating macrophages release proinflammatory cytokines that trigger insulin resistance. An adipocyte-based platform from visceral fat would be useful to elucidate the pathology of adipose inflammation and to develop therapeutic drugs for insulin resistance. ADSCs (adipose tissue-derived mesenchymal stromal cells) expanded from subcutaneous fat are intensively studied as sources for regenerative medicine. However, the adipocyte culture system from visceral fat tissue has not been utilized yet. We aimed to establish the bioactive adipocyte platform using ADSCs from visceral fat pad. Stromal vascular fractions were processed from epididymal fat pads of Sprague-Dawley rats and three human omental fat pads, and the ADSCs were expanded using a low-serum culture method. The responses of ADSCs and ADSC-adipocytes (their adipogenic lineages) to pioglitazone, a therapeutic drug for diabesity, were evaluated by gene expression and ELISA. ADSCs (1×108) were expanded from 10 g of rat epididymal fat pads or human omental fat pads over five passages. Cell surface marker expressions revealed that visceral ADSCs were equivalent to mesenchymal stem cells. ADSC-adipocytes expanded in the low-serum culture system significantly showed higher expression of adipogenic markers [PPAR (peroxisome proliferator-activated receptor) γ, LPL (lipoprotein lipase) and FABP4 (fatty acid-binding protein 4)] and adipocytokines [adiponectin, resistin, leptin, PAI-1 (plasminogen-activator inhibitor 1) and IL (interleukin)-10] than those expanded in a high-serum culture system. Pioglitazone accelerated the adipogenic induction and increased adiponectin expression in human ADSCs by 57.9±5.8-fold (mean±S.E.M.) relative to control cells (P<0.001). Both in rat and human ADSC-adipocytes, TNF-α significantly induced proinflammatory cytokines [MCP-1 (monocyte chemoattractant protein-1) and IL-6] and suppressed adiponectin expression, while pioglitazone antagonized these effects. The present findings suggest that visceral ADSC-adipocytes expanded in low-serum culture would be useful for adiposcience and pharmacological evaluations.     

Anticancer drugs cause release of exosomes with heat shock proteins from human hepatocellular carcinoma cells that elicit effective natural killer cell antitumor responses in vitro

Failure of immune surveillance related to inadequate host antitumor immune responses has been suggested as a possible cause of the high incidence of recurrence and poor overall survival outcome of hepatocellular carcinoma. The stress-induced heat shock proteins (HSPs) are known to act as endogenous "danger signals" that can improve tumor immunogenicity and induce natural killer (NK) cell responses. Exosome is a novel secretory pathway for HSPs. In our experiments, the immune regulatory effect of the HSP-bearing exosomes secreted by human hepatocellular carcinoma cells under stress conditions on NK cells was studied. ELISA results showed that the production of HSP60, HSP70, and HSP90 was up-regulated in both cell lines in a stress-specific manner. After exposure to hepatocellular carcinoma cell-resistant or sensitive anticancer drugs (hereafter referred to as "resistant" or "sensitive" anticancer drug), the membrane microvesicles were actively released by hepatocellular carcinoma cells, differing in their ability to present HSPs on the cell surface, which were characterized as exosomes. Acting as a decoy, the HSP-bearing exosomes efficiently stimulated NK cell cytotoxicity and granzyme B production, up-regulated the expression of inhibitory receptor CD94, and down-regulated the expression of activating receptors CD69, NKG2D, and NKp44. Notably, resistant anticancer drugs enhanced exosome release and generated more exosome-carried HSPs, which augmented the activation of the cytotoxic response. In summary, our findings demonstrated that exosomes derived from resistant anticancer drug-treated HepG2 cells conferred superior immunogenicity in inducing HSP-specific NK cell responses, which provided a clue for finding an efficient vaccine for hepatocellular carcinoma immunotherapy.     

1982-2016年东北黑土区植被NDVI动态及其对气候变化的响应

植被是陆地生态系统的重要组成部分,在调节气候、水土保持等方面具有重要作用,因此,监测植被生长变化并探讨其与气候变化之间的关系,在全球变化研究中具有重要意义。基于MODIS NDVI和GIMMS NDVI数据集,并通过一致性检验,在区域和像元两个空间尺度上,利用一元线性回归模型,研究东北黑土区1982-2016年植被生长动态,分析植被生长对气温和降水量的响应程度。结果表明：区域尺度上,1982-2016年东北黑土区植被生长季NDVI变化分为3个阶段（先增加继而减少最后再增加）,区域植被的生长在气温、降水量的共同作用下,呈现出明显季节差异;像元尺度上,1982-2016年东北黑土区NDVI总体趋势为改善状态,主要改善植被类型为草原、森林和农业植被,鹤岗市、绥化市和长春市改善面积较大;多年平均NDVI值与同期气温和降水量具有一定的相关关系,平原地区植被NDVI与气温主要呈显著正相关关系,植被类型主要为耕地;平原地区边缘和山地地区的植被NDVI与降水量以显著正相关关系为主,主要植被类型为森林和草地。     

西昌万寿菊花中化学成分的研究

从万寿菊（Tagetes ereata L．）花中分得8个已知化合物,分别为丁香酸（Syringic acid,1）,3,4二羟基苯甲酸（3,4-dihydroxybenzonic acid,2）,β-香树脂醇（β-amyrin,3）,槲皮万寿菊素（Quercetagetin,4）,Quercetagetin 7-methyl（5）,β-谷甾醇（β-sitosterol,6）,豆甾醇（stigmasterol,7）,正三十四烷（Tetratriacontane,8）。应用光谱法鉴定了所有化合物的结构。