从基因、遗传密码到基因组学和生物信息学

DNA双螺旋模型的建成是20世纪生物学领域极为重要的发现,它为现代分子生物学的发展奠定了基础。DNA结构的发现和后来“中心法则”的提出,以及随后发明的重组DNA和分子克隆技术,使人类获得了崭新的干预生物进化和优化生物的某些功能的有效手段和途径。而20世纪90年代以来,基因组学和生物信息学无疑已成为当前和今后相当长的时期内较活跃和影响较大的生物科学前沿学科。回顾20世纪生物科学发展的主要路线和过程,可以清楚地看到,DNA双螺旋模型在其中所处的承上启下的关键位置和所起到的核心作用。因此．研究、了解DNA双螺旋模型产生的背景、条件,及其对生物学发展产生的积极影响,对我们深刻认识这一重大发现的科学价值,正确把握现代生命科学发展的规律和方向,是大有裨益的。     

DNA双螺旋结构模型与生物医学的发展

DNA双螺旋模型的建立大大推进了生物医学的研究,基因工程技术的诞生和临床医学的发展,已经成为生命科学发展史中的一个里程碑,     

The effects of torture‐related stressors on long‐term complex post‐traumatic symptoms in South Korean torture survivors

This study explored whether perceived distress from specific stressors during and after torture explain long‐term complex post‐traumatic symptoms of South Korean torture survivors. We conducted a cross‐sectional survey of survivors who had been tortured by the homeland regime from the 1970s to the 2000s. Data from 206 survivors were gathered by key informants using target sampling and snowballing techniques. Project staff designed scales to encompass the specific types of stressors related to torture techniques used in Korea. Frequencies and distress ratings of exposure to torture, post‐torture psychosocial stressors and physical damage related to torture were gathered. Psychological symptoms were assessed by the Impact of Event Scale‐Revised‐Korean version and subscales of the Symptom Checklist 90‐Revised‐Korean version. Perceived distress from torture stressors was mainly divided into factors representing physical, psychological and deprivation torture by adapting a principal axis factor analysis. Hierarchical regression analyses showed that distress from psychological torture explained post‐traumatic stress disorder (PTSD) and that distress from deprivation explained PTSD and anxiety after controlling for demographic variables, psychological preparedness, time span since torture and distress from trauma other than torture. Among post‐torture stressors, distress from physical damage related to torture and social exclusion were strong indicators of complex symptoms.     

影响群体道歉有效性的因素

影响群体道歉有效性的因素是多方面的。对侵犯群体而言, 有效的群体道歉需要在言语表达中包含承认错误、承担责任、表达懊悔、做出承诺等内容, 需要讲究群体道歉的行为策略, 同时还应该关注道歉的内部动机对语言表达与行为方式的影响。对受害群体来讲, 侵犯群体道歉的有效性在于道歉本身缓解了其愤怒情绪, 满足了其自尊和期望等心理需求, 同时还要受到他们对道歉真诚性知觉程度的影响。除此之外, 群体道歉还会受到群际关系质量、冲突程度、文化信念等外部因素的影响。在今后的研究中, 应该继续尝试整合群体道歉的过程机制, 丰富群体道歉有效性的考察指标, 发挥道歉在社会生活领域中的积极作用。     

Understanding Motor Awareness Through Normal and Pathological Behavior

ABSTRACT— Data on patients with localized brain damage and on neurologically intact subjects show that normal motor control depends on the functionality of a chain of neurobiological events. These events, through the activation of internal representations of the desired, predicted, and actual condition of one's body with respect to the external world, contribute to the construction of conscious knowledge of voluntary actions and to self-awareness.     

DNA methylation of NR3c1 in infancy: Associations between maternal caregiving and infant sex

Caregivers play a critical role in scaffolding infant stress reactivity and regulation, but the mechanisms by which this scaffolding occurs is unclear. Animal models strongly suggest that epigenetic processes, such as DNA methylation, are sensitive to caregiving behaviors and, in turn, offspring stress reactivity. We examined the direct effects of caregiving behaviors on DNA methylation in infants and infant stress reactivity. Infants and mothers (N = 128) were assessed during a free play when infants were 5 months old. Maternal responsiveness and appropriate touch were coded. and infant buccal epithelial cells were sampled to assess for DNA methylation of the glucocorticoid receptor gene, NR3c1 exon 1F. Infant cortisol reactivity was assessed in response to the still-face paradigm. Greater levels of maternal responsiveness and appropriate touch were related to less DNA methylation of specific regions in NR3c1 exon 1F, but only for females. There was no association with maternal responsiveness and appropriate touch or DNA methylation of NR3c1 exon 1F on prestress cortisol or cortisol reactivity. Our results are discussed in relation to programming models that implicate maternal care as an important factor in programing infant stress reactivity.     

非稳态噪声对动物行为及心脏自由基损伤的影响

本研究用采集的多用木工机床和冲击电钻发出的噪声对 5天、1 0天和 2 0天三个噪声干扰组的动物进行干扰 ,以研究非稳态噪声对动物行为及心脏组织自由基损伤的影响。结果发现 ,非稳态噪声可引起动物旷场反应中走格数减少 ,站立及洗脸次数增加 ,并可诱发心脏组织的自由基反应 ,导致心脏组织的损害。因此得出结论 :①非稳态噪声可以对动物行为产生影响 ,并随着噪声暴露时间的延长而增强 ;②非稳态噪声可以造成心脏组织的自由基损伤。这一现象提示自由基损伤是介导噪声对心脏功能影响的重要因素之一。     

Bilateral facilitation of motor control in chronic hemiplegia

The present study addressed the efficacy of concurrently moving both arms, with and without a load added to the uninvolved arm, in facilitating the quality of movement of the involved side in individuals with moderate, chronic hemiplegia. Six hemiplegic cerebrovascular accident (CVA) subjects with left-hemisphere lesions participated in the study. The four males and two females ranged from 46 to 77 years of age and 30–96 months post-CVA. All subjects scored at least 70% on the Fugl-Meyer test of motor function. The task was to perform discrete unilateral and bilateral elbow extensions in the horizontal plane. The movements were 45° in amplitude and were to terminate in a 10° target zone that was indicated by an illustration of a coffee mug. The instructions were to move toward the mug as smoothly as possible in a movement time (MT) determined to be 20% longer than their minimal MT for that distance. The primary dependent variable was the percentage of continuous vs. discontinuous trajectories observed in each condition, based on whether or not a transient hesitation or reversal was observed. Phase of peak velocity was also quantified as a general indication of the symmetry of the velocity profile. Three of the six subjects exhibited a greater percentage of continuous movements of the involved arm in the nonloaded bilateral condition than the unimanual condition. Five subjects benefited when the uninvolved arm was inertially loaded in the bilateral condition when compared with unimanual performance. Only the oldest subject failed to exhibit facilitation. Peak velocity phase tended to normalize toward symmetry in the bilateral conditions. These findings are consistent with prior evidence that the control of the involved arm improves during bimanual performance for some hemiplegic subjects. It further suggests loading the uninvolved arm may benefit some subjects with respect to unimanual performance, with age perhaps playing a role in determining efficacy.     

Preserved visual lexicosemantics in global aphasia: a right-hemisphere contribution?

Extensive testing of a patient, GP, who encountered large-scale destruction of left-hemisphere (LH) language regions was undertaken in order to address several issues concerning the ability of nonperisylvian areas to extract meaning from printed words. Testing revealed recognition of superordinate boundaries of animals, tools, vegetables, fruit, clothes, and furniture. GP was able to distinguish proper names from other nouns and from nonwords. GP was also able to differentiate words representing living things from those denoting nonliving things. The extent of LH infarct resulting in a global impairment to phonological and syntactic processing suggests LH specificity for these functions but considerable right-hemisphere (RH) participation in visual lexicosemantic processing. The relative preservation of visual lexicosemantic abilities despite severe impairment to all aspects of phonological coding demonstrates the importance of the direct route to the meaning of single printed words.