北京地区红隼的迁徙路线和活动区域

红隼(Falco tinnunculus)被列为国家二级重点保护野生动物,是能同时适应农村和城市环境的小型猛禽,对维持城市生态系统稳定具有重要意义。2022年4月至7月,为在北京救助的7只红隼佩戴了卫星追踪器,追踪其活动轨迹,依据追踪的动物活动位点数据,采用净平方位移-时间曲线依次对各红隼的迁徙模式进行了判别,深入分析了迁徙红隼的迁徙时间、距离和路线等,并采用核心密度法分别计算了迁徙及留居型红隼95%及50%活动区面积。研究结果表明,在北京地区红隼的迁徙模式为部分迁徙,追踪的7只红隼个体(N01 ~ N07)中,4只为留鸟,1只为迁徙鸟,2只居留类型无法准确判断。N01为迁徙红隼,其度夏地和越冬地分别在内蒙古锡林郭勒盟和河北廊坊,此红隼秋季迁徙速度明显高于春季,其春季迁徙距离551 km,历时25 d,平均迁徙速度为22 km/d,而秋季迁徙距离412 km,历时2 d,平均迁徙速度为203 km/d,河北承德滦平县是其春季迁徙的重要中途停歇地。不同红隼个体间95%及50%活动区面积均存在较大差异,迁徙红隼N01 95%、50%活动区面积在度夏区分别为93.10 km²、17.50 km²,在越冬区分别为7.03 km²、0.99 km²;留居型红隼95%、50%活动区面积均值分别为1 165.34 km²、178.71 km²(n = 4),其中最大95%、50%活动区面积分别为4 320.26 km²(N02)、648.22 km²(N02),最小95%、50%活动区面积分别为2.80 km²(N03)、0.29 km²(N03)。本研究揭示了北京地区红隼的迁徙模式、迁徙路线、重要停歇地及活动区状况,为红隼的针对性保护和管理提供了科学依据。     

湖南沅江鼎城段河蚬的性别组成与精子形态特征

本研究以湖南沅江鼎城段河蚬(Corbicula fluminea)为研究对象,在进一步验证该群体性别组成的基础上,分析壳长组成与性别比例之间关系,探讨该群体雄性、雌性和雌雄同体之间关系;同时以单鞭毛精子为参照,分析比较双鞭毛精子的形态特征,以期为我国河蚬的性别发生及生殖适应策略研究提供基础资料。结果显示：沅江鼎城段河蚬(n = 770)雄性、雌性和雌雄同体最小性成熟壳长分别为2.92 mm、5.66 mm和5.30 mm。697只性成熟河蚬中雄性、雌性和雌雄同体的比例近似1︰1︰6。雌雄同体的平均壳长[(22.55 ± 0.33)mm,n = 517]显著大于雄性[(20.44 ± 1.03)mm,n = 95]和雌性[(19.79 ± 0.99)mm,n = 85](P < 0.05),但雄性与雌性的平均壳长之间差异不显著(P > 0.05)。河蚬可以产生单鞭毛和双鞭毛两种类型的精子,单鞭毛精子头长范围4.93 ~ 21.79 μm,平均值(14.27 ± 0.82)μm(n = 30),双鞭毛精子头长范围10.29 ~ 22.04 μm,平均值(15.62 ± 0.62)μm(n = 26)。单、双鞭毛精子头长差异不显著(P > 0.05)。双鞭毛精子(n = 26)长尾的平均长度[(38.07 ± 1.44)μm]显著大于其短尾[(31.08 ± 1.60)μm]和单鞭毛精子(n = 30)尾部长度[(30.15 ± 1.75)μm](P < 0.01),但其短尾与单鞭毛精子的尾部平均长度之间无显著性差异(P > 0.05)。结果表明：湖南沅江鼎城段河蚬为雄性先熟,且可能存在雄性和(或)雌性向雌雄同体转换现象。河蚬具有单鞭毛型和双鞭毛型2种类型的精子,且双鞭毛精子的2个尾部不等长。同域共存河蚬的单鞭毛与双鞭毛精子在运动及受精能力方面的差异值得深入研究。     

PML/RARalpha fusion protein mediates the unique sensitivity to arsenic cytotoxicity in acute promyelocytic leukemia cells: Mechanisms involve the impairment of cAMP signaling and the aberrant regulation of NADPH oxidase

Acute promyelocytic leukemia (APL) cells are characterized by PML/RARalpha fusion protein, high responsiveness to arsenic trioxide (ATO)-induced cytotoxicity and an abundant generation of reactive oxygen species (ROS). In this study we investigated the association among these three features in APL-derived NB4 cells. We found that NADPH oxidase-derived ROS generation was more abundant in NB4 cells compared with monocytic leukemia U937 cells. By using PR9, a sub-line of U937 stably transduced with the inducible PML/RARalpha expression vectors, we attributed disparities on ROS generation and ATO sensitivity to the occurrence of PML/RARalpha fusion protein, since PML/RARalpha-expressing cells appeared higher NADPH oxidase activity, higher ROS level and higher sensitivity to ATO. On the other hand, the basal intensity of cAMP signaling pathway was compared between NB4 and U937 as well as between PR9 cells with or without PML/RARalpha, demonstrating that PML/RARalpha-expressing cells had an impaired cAMP signaling pathway which relieved its inhibitory effect on NADPH oxidase derived ROS generation. In summary, the present study demonstrated the correlation of PML/RARalpha with cAMP signaling pathway, NADPH oxidase and ROS generation in APL cells. PML/RARalpha that bestows NB4 cells various pathological features, paradoxically also endows these cells with the basis for susceptibility to ATO-induced cytotoxcity.     

牛肝菌属卷边组Boletus sect. Appendiculati物种的分子识别

依据牛肝菌属卷边组Boletus sect. Appendiculati内7个物种的核糖体基因rDNA内转录间隔区（internal transcribed spacer,ITS）序列比对,设计5对ITS特异引物,分别用于卷边牛肝菌Boletus appendiculatus与亚卷边牛肝菌B. subappendiculatus、卷边牛肝菌与拟桃红牛肝菌B. pseudoregius、华靛牛肝菌B. roseoflavus与卷边牛肝菌B.?appendiculatus、华靛牛肝菌与华美牛肝菌B. speciosus、拟桃红牛肝菌与华美牛肝菌的相互识别。ITS区段的PCR扩增结果表明,5对ITS特异引物皆成功扩增出可用于辨别这些近缘物种的目的条带。但未能设计出ITS特异引物,以识别华靛牛肝菌与桃红牛肝菌B. regius两个近缘物种。     

圈养獐分娩的初步观察

2004年的5~7月,在浙江省嵊州市河麂种源繁育基地对34只獐(Hydropotes inermis)的分娩活动进行了观察。结果表明,母獐通常选择安全的地点进行分娩。獐集中分娩的时间为6月3日到6月19日,占分娩母獐总数的73.53%(n=34),并且分娩多在白天进行。产程(从胎膜露出到胎盘娩出)平均为(302.20±15.27)min(n=15)。胎儿娩出的姿势多为前躯前置(前足、头先露出),占83.78%;少数为后躯前置(后足先露出),占16.22%。幼仔首次吮乳时间在单胎和多胎间无显著差异,平均为出生后(44.97±2.73)min(n=35)。幼仔出生后首次平均站立时间在双胞胎、三胞胎和四胞胎分别为(32.25±2.49)min(n=16)(、29.42±2.52)min(n=12)和(65.00±7.39)min(n=6)。每胎幼仔数越多,初生幼仔的平均体重越轻。     

Electrophysiological and immunocytochemical characterization of DRG neurons on an organosilane surface in serum-free medium

We are attempting to recreate a stretch reflex circuit on a patterned Bio-MEMS (bio-microelectromechanical systems) chip with deflecting micro-cantilevers. The first steps to recreate this system is to be able to grow individual components of the circuit (sensory neuron, motoneuron, skeletal muscle, and muscle spindle) on a patternable, synthetic substrate coating the MEMS device. Sensory neurons represent the afferent portion of the stretch reflex arc and also play a significant role in transmitting the signal from the muscle spindle to the spinal cord motoneurons. We have utilized a synthetic silane substrate N-1[3-(trimethoxysilyl) propyl) diethylenetriamine (DETA) on which to grow and pattern the cells. DETA forms a self-assembled monolayer on a variety of silicon substrates, including glass, and can be patterned using photolithography. In this paper, we have evaluated the growth of sensory neurons on this synthetic silane substrate. We have investigated the immunocytochemical and electrophysiological properties of the sensory neurons on DETA and compared the resultant properties with a biological control substrate (ornithine/laminin). Immunocytochemical studies revealed the survival and growth of all three subtypes of sensory neurons: trkA, trkB, and trkC on both surfaces. Furthermore, whole-cell patch clamp recordings were used to study the electrophysiological properties of the sensory neurons on the two surfaces. There were no significant differences in the electrical properties of the neurons grown on either surface. This is the first study analyzing the immunocytochemical and electrophysiological properties of sensory neurons grown long-term in a completely defined environment and on a nonbiological substrate.     

通过染色体外同源重组建立乳腺中表达外源基因的转基因小鼠

为研究染色体外重组方法在创建转基因动物中的应用,选取牛asl酪蛋白基因的5′及3′侧翼区和氯霉素乙酰化酶编码区,构建了两个具有3 kb相互重叠的融合基因.将这两个DNA片段末端脱磷酸后,以摩尔比1:1的比例混合,通过显微注射导入小鼠受精原核,最后获得了11个品系的转基因小鼠.对其中10个品系的小鼠的整合分析表明,所注射的两个DNA片段均发生了染色体外同源重组,而且除了 1个品系的小鼠丢失了大约1kb的序列外,其余品系小鼠的重组产物与预想的结构符合.在当代和后代的转基因小鼠乳汁中均可测到氯霉素乙酰化酶的活性.这表明融合基因在转基因小鼠乳腺中得到表达和分泌,也说明显微共注射两个相互重叠的基因片段是建立转基因动物的一个可行途径.     

Targeting UPR branches,a potential strategy for enhancing efficacy of cancer chemotherapy

Cancer cells are often exposed to cell intrinsic stresses and environmental perturbations that may lead to accumulation of unfolded and/or misfolded proteins in...     

城市生态规划的回顾与展望

回顾了城市生态规划的发展情况,对其发展前景进行了展望。从19世纪末至今,从Howard的“田园城市”到MacHarg的土地利用生态规划方法,再到基于生态系统理论的城市生态对策规划,城市生态规划的理论和方法在实践中不断完善。全球城市化进程的加快带来了一系列的生态环境问题。城市生态规划作为实现城市可持续发展的途径之一,越来越受到人们的关注,为生态城市建设服务是城市生态规划的发展方向。