Distinguishing features of immature stages of Panchaetothripinae (Thysanoptera: Thripidae) known in New Zealand

Diagnostic morphological characters of the juvenile Panchaetothripinae in New Zealand are illustrated. Keys developed enable colonies with only immature stages to be identified without needing to rear adults. Live larvae or larvae in ethanol are distinguished by the presence of expanded tips of body setae (Parthenothrips dracaenae), the absence of setae at the abdomen tip (Hercinothrips bicinctus), setae at abdomen tip not longer than abdominal tip width (Heliothrips haemorrhoidalis) and abdominal tip setae longer than abdominal tip width (Sigmothrips aotearoana, endemic species). The presence or absence of spine-like setae on abdominal segments 9 and 10, and the number and length of setae on the wing buds, enable identification of pupae. Abdominal spine-like setae were on the prepupa and pupa of H. bicinctus and S. aotearoana, species that pupate off the plant, and are probably defensive structures. This is the first record of spine-like setae on segment 10 of terebrantian pupae.     

11个绵羊品种MSTN基因非翻译区的变异

利用PCR-RFLP技术对特克塞尔羊、夏洛莱羊、小尾寒羊、蒙古羊、乌珠穆沁羊、阿勒泰羊、呼伦贝尔羊、塔什库尔干羊、多浪羊、湖羊和岗巴羊11个品种的345个个体的肌肉生长抑制素(Myostatin, MSTN)基因非翻译区(UTR)的变异进行了多态性分析。结果表明大小为271 bp和1 003 bp的扩增片段经限制性内切酶MboⅡ和BsaⅠ酶切后表现多态, 经卡方检验所有品种在该基因座位均处于平衡状态(P>0.05), 3种基因型在11个绵羊品种中的分布差异极显著(P<0.01)。通过限制性内切酶HpyCH4Ⅳ 酶切实验, 证明我国9个地方绵羊品种不存在特克塞尔绵羊中发现的导致肌肉发达的SNP位点, 并在3′UTR区发现了个别碱基突变位点能够形成miRNA作用的靶基序, 测序表明3′UTR区的突变频率较高。     

抗菌肽对种植体周围炎主要致病菌生长抑制作用的研究

目的研究抗菌肽KSL及其衍生物KSL—W对种植体周围炎主要致病菌的体外抑菌效果。方法应用二倍稀释法检测KSL和KSL—W对血链球菌、具梭核杆菌和牙龈卟啉单胞菌的最小抑菌浓度（MIC）和最小杀菌浓度（MBC）;MTT法检测KSL和KSL—W对成骨样细胞MG-63的细胞毒性。结果KSL和KSL—W对具梭核杆菌的MIC和MBC分别为0．0156mg／mL和0．0313mg／mL,对牙龈卟啉单胞菌的MIC和MBC分别为0．125mg／mL和0．5mg／mL,在0．5mg／mL的浓度范围内对血链球菌没有抑制作用;KSL和KSL-W在0．5mg／mL的浓度范围内没有细胞毒性。结论KSL和KSL—W没有细胞毒性,对具梭核杆菌和牙龈卟啉单胞菌具有抑制作用。     

Distracting the mind improves performance: an ERP Study

Background

When a second target (T2) is presented in close succession of a first target (T1), people often fail to identify T2, a phenomenon known as the attentional blink (AB). However, the AB can be reduced substantially when participants are distracted during the task, for instance by a concurrent task, without a cost for T1 performance. The goal of the current study was to investigate the electrophysiological correlates of this paradoxical effect.

Methodology/Principal Findings

Participants successively performed three tasks, while EEG was recorded. The first task (standard AB) consisted of identifying two target letters in a sequential stream of distractor digits. The second task (grey dots task) was similar to the first task with the addition of an irrelevant grey dot moving in the periphery, concurrent with the central stimulus stream. The third task (red dot task) was similar to the second task, except that detection of an occasional brief color change in the moving grey dot was required. AB magnitude in the latter task was significantly smaller, whereas behavioral performance in the standard and grey dots tasks did not differ. Using mixed effects models, electrophysiological activity was compared during trials in the grey dots and red dot tasks that differed in task instruction but not in perceptual input. In the red dot task, both target-related parietal brain activity associated with working memory updating (P3) as well as distractor-related occipital activity was significantly reduced.

Conclusions/Significance

The results support the idea that the AB might (at least partly) arise from an overinvestment of attentional resources or an overexertion of attentional control, which is reduced when a distracting secondary task is carried out. The present findings bring us a step closer in understanding why and how an AB occurs, and how these temporal restrictions in selective attention can be overcome.     

植物悬浮细胞的研究进展

综述了植物悬浮细胞培养的原理、培养类型、不同植物悬浮细胞培养基的配方和培养方法.同时阐述了悬浮细胞系在细胞生物学和分子生物学领域中的应用前景.     

Up-regulation of multiple serine proteinases during earthworm tail regeneration

Summary

Previous studies have shown that spatiotemporal regulation of extracellular matrix (ECM) by proteinases is implicated in the initial step of regeneration. In amphibian regeneration, the up-regulation of proteinases such as metalloproteinases (MMPs) and cathepsin D, and proteinase-related proteins such as proteinase tissue inhibitors and activators has been demonstrated. Since the earthworm could provide a unique and valuable model to investigate the mechanism of regeneration, we studied the developmental change in proteinase expression during earthworm tail regeneration. Zymographic analysis revealed that proteinase activities began to increase within 1 h after amputation and reached a maximum at 7 days post-amputation. This peak in activity was approximately 22-fold greater than the unamputated controls. Thereafter, the proteinase activities tended to decrease followed by another peak at 30 days before returning to control levels. At least four types of proteinase were distinguishable at 7 and 30 days post-amputation, with molecular weights of 25, 28, 38, and 44 kDa, respectively. All proteinase activities were strongly inhibited by addition of phenylmethylsulfonyl fluoride (PMSF) and aprotinin, specific inhibitors for serine proteinase. Pepstatin A, E-64, iodoacetamide and a metal ion-free medium were not effective inhibitors, indicating that proteinases expressed during earthworm tail regeneration would be serine proteinases. In addition, we were able to detect two types of plasminogen activator (PA) with molecular weights of 40 and 47 kDa, respectively. PA activities were predominantly expressed at 1, 5, and 25 days post-amputation, which preceded two peaks of serine proteinase activities appearing at approximately 7 and 30 days after amputation, respectively. This fact supports the view that serine proteinases expressed in respond to tail amputation may be plasmin-like proteinases activated by PA.