Olfactory discrimination learning in mice lacking the fragile X mental retardation protein

An automated training system was used to compare the behavior of knockout (KO) mice lacking the fragile X mental retardation protein with that of wild-type (WT) mice (C57Bl/6 strain) in the acquisition and retention of olfactory discriminations. KO and WT mice did not differ in the acquisition of a four-stage nose poke shaping procedure. In two separate experiments, mutant mice required substantially more training to acquire a series of novel olfactory discrimination problems than did control mice. The KO mice required significantly more sessions to reach criterion performance, made significantly more errors during training, and more often failed to acquire discriminations. Both KO and WT mice showed similar error patterns when learning novel discriminations and both groups showed evidence of more rapid learning of later discriminations in the problem series. Both groups showed significant long-term memory two or four weeks after training but WT and KO mice did not differ in this regard. A group of well-trained mice were given training on novel odors in sessions limited to 20–80 trials. Memory of these problems at two day delays did not differ between WT and KO mice. Tests using ethyl acetate demonstrated that WT and KO mice had similar odor detection thresholds.     

A neural model of how the brain computes heading from optic flow in realistic scenes

Visually-based navigation is a key competence during spatial cognition. Animals avoid obstacles and approach goals in novel cluttered environments using optic flow to compute heading with respect to the environment. Most navigation models try either explain data, or to demonstrate navigational competence in real-world environments without regard to behavioral and neural substrates. The current article develops a model that does both. The ViSTARS neural model describes interactions among neurons in the primate magnocellular pathway, including V1, MT⁺, and MSTd. Model outputs are quantitatively similar to human heading data in response to complex natural scenes. The model estimates heading to within 1.5° in random dot or photo-realistically rendered scenes, and within 3° in video streams from driving in real-world environments. Simulated rotations of less than 1°/s do not affect heading estimates, but faster simulated rotation rates do, as in humans. The model is part of a larger navigational system that identifies and tracks objects while navigating in cluttered environments.     

伏隔核和中脑腹侧被盖区内食欲素在吗啡奖赏中的作用

实验采用条件性位置偏爱（CPP）模型考察中脑腹侧被盖区（VTA）和伏隔核壳区（NAcSh）内食欲素（orexin）在吗啡奖赏中的作用。Wistar大鼠分为盐水训练组和吗啡训练组。3轮吗啡（或盐水）匹配训练前,双侧VTA或NAcSh内给予OXR1拮抗剂SB334867（VTA: 0, 1, 5μg;NAcSh: 0, 1, 3μg）;或2轮吗啡（或盐水）匹配训练前NAcSh内给予orexin A（0, 2, 4, 6μg）,观察其对吗啡CPP建立的影响。结果表明,VTA内给予SB334867抑制吗啡CPP建立,并存在剂量效应关系;NAcSh内给予SB334867或orexin A均未影响吗啡CPP建立,而orexin A可增加吗啡处理大鼠的运动性。以上结果表明,VTA和NAcSh内的orexin在吗啡奖赏中扮演的角色不同,可能调控成瘾行为的不同成分     

内质网应激和胰岛素抵抗

2型糖尿病的发病机制主要涉及胰岛素抵抗,近年来研究表明内质网应激可诱导胰岛素抵抗的形成,并使与改善胰岛素受体敏感性相关的内质网应激标志物分子氧调节蛋白150和转录因子X盒结合蛋白-1表达增强,表明内质网应激对细胞具有双重作用,一方面可诱导胰岛素抵抗,另一方面激发对应激的适应反应。     

鼻咽癌组织VEGF、TNF—α及其受体VEGFR1、P55的表达及意义

观察鼻咽癌黏膜上皮中血管内皮生长因子（VEGF）、肿瘤坏死因子α（TNF—α）及受体血管生长因子1（VEGFR1）,肿瘤坏死生长因子受体蛋白55（P55）的表达情况,探讨其在鼻咽癌发病及进展中的意义。我们应用免疫组化SP法检测60例鼻咽癌和60例正常鼻黏膜上皮组织VEGF、TNF—α及VEGFR1、P55表达情况,分析其在鼻咽癌组织中的表达变化及意义。结果显示鼻咽癌黏膜上皮的VEGF、TNF—α、VEGFR1、P55表达高于正常鼻黏膜上皮。因此VEGF、TNF—α及其受体VEGFR1、P55在鼻咽癌黏膜上皮中过度表达,可能参与鼻咽癌的发病及疾病进展,对于鼻咽癌的预防及治疗具有重要意义。     

捡了西瓜，就该丢掉芝麻吗——浅谈医源性Wernicke脑病

探讨医源性Wernicke脑病（WE）的病因、临床及磁共振图像特点,回顾性分析6例医源性WE病例。医源性WE病前均有禁食史,其临床表现多样。磁共振图像为中脑导水管周围T2WI及Flair高信号。大部分病例补充维生素B1后可好转。提示医源性禁食导致体内维生素B1耗竭是医源性WE的病因,及时补充维生素B1是预防及治疗本病的关键。     

Perceptions of Type 1 Diabetes among Affected Youth and their Peers

Management of type 1 diabetes (T1D) involves balancing several components including diet, exercise, and medication. Peer involvement in management tasks is an important, but understudied, issue in T1D. This study presents results of a preliminary examination of perceptions of disease management in youth with T1D and their peers. Data were collected using a mixed methods (qualitative and quantitative data) approach during medical education time at a camp for youth with T1D and their peers. Results suggest that both youth with T1D and their peers believe that peers need more information about medical consequences of having diabetes. Further, youth with T1D and their peers would like coaching on how peers may help the child with T1D manage their illness better. Results provide preliminary ideas for intervention (i.e., including peers, assessing social support) in the medical setting as well as ideas for future research (i.e., examining relationships among perceptions and gender, time since diagnosis).     

Across the Spectrum: Case Studies in Genetic Counseling for Breast and Ovarian Cancer

We present three vignettes based on participants counseled as part of a clinical research program. These include a young unaffected woman at risk for a familial mutation, a newly diagnosed breast cancer patient, and a woman with recurrent ovarian cancer. Through the use of detailed vignettes, multifaceted issues that arise in cancer genetic counseling are highlighted.     

朱熹对宋代易学的发展——兼论朱熹、程颐易学思想之异同

朱熹提出《易》之本义为卜筮的见解,由此对程颐易学和义理学派提出批评。朱熹主张区分《周易》经传,提出易学发展阶段说。通过比较《周易本义》和《周易程氏传》,可见两者之异同。朱熹以象数、卜筮求易理,把义理学派与象数学派统一起来,从而发展了宋代易学。     

试论《周易参同契》以“易”为核心的发展变化观

本文尝试从汉易学所主张的“易一名而含三义”义理出发,来考察《周易参同契》所蕴含的易学思想。从“易简”之义看,《参同契》突出了乾坤二卦法象着宇宙天地的生成变化法则及乾坤体性表现为“自然”而无人为的情态。从“变易”之义看,《参同契》主要是借鉴汉易学的“纳甲说”和“十二消息卦说”,来探讨天地判分之后阴阳之气的变通迭更过程。进而法象修仙之秩序或步骤。以及所应注意的火候进退或身体气息变化等。从“不易”之义看,《参同契》以乾坤二卦为体,坎离二卦为用,来比拟宇宙的张设布列之结构及相应变化过程。《参同契》已将《周易》之义理创造性地运用于炼丹的实践当中。