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关键词： gender dysphoria   reliability   scan-rescan   sexual orientation   transgender  

摘要： Although the neuroanatomy of transgender persons is slowly being charted, findings are presently discrepant. Moreover, the major body of work has focused on Western populations. One important factor is the issue of power and low signal-to-noise (SNR) ratio in neuroimaging studies of rare study populations including endocrine or neurological patient groups. The present study focused on the structural neuroanatomy of a Non-Western (Iranian) sample of 40 transgender men (TM), 40 transgender women (TW), 30 cisgender men (CM), and 30 cisgender women (CW), while assessing whether the reliability of findings across structural anatomical measures including gray matter volume (GMV), cortical surface area (CSA), and cortical thickness (CTh) could be increased by using two back-to-back within-session structural MRI scans. Overall, findings in transgender persons were more consistent with sex assigned at birth in GMV and CSA, while no group differences emerged for CTh. Repeated measures analysis also indicated that having a second scan increased SNR in all regions of interest, most notably bilateral frontal poles, pre- and postcentral gyri and putamina. The results suggest that a simple time and cost-effective measure to improve SNR in rare clinical populations with low prevalence rates is a second anatomical scan when structural MRI is of interest.

关键词： two-way avoidance acquisition   anxiety   fear   freezing   active avoidance   anxiolytic treatments   anxiogenic treatments   septo-hippocampal system   amygdala circuitry  

摘要： Two-way active avoidance (TWAA) acquisition constitutes a particular case of approach -avoidance conflict for laboratory rodents. The present article reviews behavioural, psychopharmacological and neuroanatomical evidence accumulated along more than fifty years that provides strong support to the contention that anxiety is critical in the transition from CS (conditioned stimulus)-induced freezing to escape/avoidance responses during the initial stages of TWAA acquisition. Thus, anxiolytic drugs of different types accelerate avoidance acquisition, anxiogenic drugs impair it, and avoidance during these initial acquisition stages is negatively associated with other typical measures of anxiety. In addition behavioural and developmental treatments that reduce or increase anxiety/stress respectively facilitate or impair TWAA acquisition. Finally, evidence for the regulation of TWAA acquisition by septo-hippocampal and amygdala-related mechanisms is discussed. Collectively, the reviewed evidence gives support to the initial acquisition of TWAA as a paradigm with considerable predictive and (in particular) construct validity as an approach-avoidance conflict-based rodent anxiety model.

关键词： nerve-sparing lymphadenectomy   pelvic and para-aortic lymph nodes   lymph node dissection   infra-renal bilateral template   aortic plexus  

摘要： Simple Summary One of the most frequent complications of the systematic lymph node dissection (SLND) is the injury of autonomic nervous system in the para-aortal region during the procedure. These injuries are supposed to be responsible for some of the postoperative bladder, bowel, and sexual dysfunctions. The poor anatomical understanding of the sympathetic nerves within the boundaries of an infra-renal bilateral template has limited the promulgation of a precise nerve-sparing surgery during such SLND. Therefore, the principal goal of the present study was to provide the first ever-comprehensive exposition of the anatomy of the female aortic plexus and superior hypogastric plexus and their variations. This exposition was achieved by strategic dissection of 19 human female cadavers and extrapolating the findings to develop a precise surgical technique for more accurate navigation into these structures during nerve-sparing SLND in 15 cervical cancer patients and 48 ovarian cancer patients. Whilst systematic lymph node dissection has been less prevalent in gynaecological cancer cases in the last few years, there is still a good number of cases that mandate a systematic lymph node dissection for diagnostic and therapeutic purposes. In all of these cases, it is crucial to perform the procedure as a nerve-sparing technique with utmost exactitude, which can be achieved optimally only by isolating and sparing all components of the aortic plexus and superior hypogastric plexus. To meet this purpose, it is essential to provide a comprehensive characterization of the specific anatomy of the human female aortic plexus and its variations. The anatomic dissections of two fresh and 17 formalin-fixed female cadavers were utilized to study, understand, and decipher the hitherto ambiguously annotated anatomy of the autonomic nervous system in the retroperitoneal para-aortic region. This study describes the precise anatomy of aortic and superior hypogastric plexus and provides the su

关键词： Sensory neurons   Periphery   Monoamines   Neuropeptides   Extrinsic modulation   Lymnaea stagnalis  

摘要： Perception and processing of chemical cues are crucial for aquatic gastropods, for proper elaboration of adaptive behavior. The pond snail,Lymnaea stagnalis, is a model species of invertebrate neurobiology, in which peripheral sensory neurons with different morphology and transmitter content have partly been described, but we have little knowledge regarding their functional morphological organization, including their possible peripheral intercellular connections and networks. Therefore the aim of our study was to characterize the sensory system of the tentacles and the lip, as primary sensory regions, and the anterior foot ofLymnaeawith special attention to the transmitter content of the sensory neurons, and their relationship to extrinsic elements of the central nervous system. Numerous bipolar sensory cells were demonstrated in the epithelial layer of the peripheral organs, displaying immunoreactivity to antibodies raised against tyrosine hydroxylase, histamine, glutamate and two molluscan type oligopeptides, FMRFamide and Mytilus inhibitory peptide. A subepithelial plexus was formed by extrinsic serotonin and FMRFamide immunoreactive fibers, whereas in deeper regions axon processess of different origin with various immunoreactivities formed networks, too. HPLC-MS assay confirmed the presence of the low molecular weight signal molecules in the three examined areas. Following double-labeling immunohistochemistry, close arrangements were observed, formed by sensory neurons and extrinsic serotonergic (and FMRFamidergic) fibers at axo-dendritic, axo-somatic and axo-axonic levels. Our results suggest the involvement of a much wider repertoire of signal molecules in peripheral sensory processes ofLymnaea, which can locally be modified by central input, hence influencing directly the responses to environmental cues.

关键词： 翻转课堂   人体解剖学   运动系统教学  

摘要： 在医学教育中,人体解剖属于一门必修基础学科,无论对于后续医学课程的学习,还是临床工作,都奠定了良好的基础。翻转课堂教学是教学实际与一线教师有机结合发起的一种教育模式改革,不仅带给现代课堂教学新活力,而且,为我国教育改革也做出了很大贡献,本文分析和研究了基于翻转课堂人体解剖学课程的“运动系统”教学策略。

关键词： AB_2337244   AB_2337249   animal vocalization   catfishes   electric fish   motor neurons   patch-clamp technique   premotor neurons  

摘要： To what extent do modifications in the nervous system and peripheral effectors contribute to novel behaviors? Using a combination of morphometric analysis, neuroanatomical tract-tracing, and intracellular neuronal recording, we address this question in a sound-producing and a weakly electric species of synodontid catfish, Synodontis grandiops, and Synodontis nigriventris, respectively. The same peripheral mechanism, a bilateral pair of protractor muscles associated with vertebral processes (elastic spring mechanism), is involved in both signaling systems. Although there were dramatic species differences in several morphometric measures, electromyograms provided strong evidence that simultaneous activation of paired protractor muscles accounts for an individual sound and electric discharge pulse. While the general architecture of the neural network and the intrinsic properties of the motoneuron population driving each target was largely similar, differences could contribute to species-specific patterns in electromyograms and the associated pulse repetition rate of sounds and electric discharges. Together, the results suggest that adaptive changes in both peripheral and central characters underlie the transition from an ancestral sound to a derived electric discharge producing system, and thus the evolution of a novel communication channel among synodontid catfish. Similarities with characters in other sonic and weakly electric teleost fish provide a striking example of convergent evolution in functional adaptations underlying the evolution of the two signaling systems among distantly related taxa.

关键词： network dynamics   head direction   Drosophila   electron microscopy   RNA-seq   two-photon calcium imaging   behavior   central complex   navigation   neural circuit  

摘要： Neural representations of head direction (HD) have been discovered in many species. Theoretical work has proposed that the dynamics associated with these representations are generated, maintained, and updated by recurrent network structures called ring attractors. We evaluated this theorized structure-function relationship by performing electron-microscopy-based circuit reconstruction and RNA profiling of identified cell types in the HD system of Drosophila melanogaster. We identified motifs that have been hypothesized to maintain the HD representation in darkness, update it when the animal turns, and tether it to visual cues. Functional studies provided support for the proposed roles of individual excitatory or inhibitory circuit elements in shaping activity. We also discovered recurrent connections between neuronal arbors with mixed pre- and postsynaptic specializations. Our results confirm that the Drosophila HD network contains the core components of a ring attractor while also revealing unpredicted structural features that might enhance the network's computational power.