Dendritic spine abnormalities in the occipital cortex of C57BL/6 Fmr1 knockout mice.

Fragile X syndrome (FXS) is the most common form of inherited mental retardation. Observed neuropathologies associated with FXS include abnormal length, morphology, and density of dendritic spines, reported in individuals with FXS and in Fmr1 knockout (KO) mice, an animal model of FXS. To date, however, these neuropathologies have been studied in Fmr1 KO mice bred in a FVB background (a strain with genetic mutations that complicate interpretation of results) and findings have been inconsistent. Here, Golgi-Cox impregnation was used to investigate length, morphology, and density of dendritic spines on layer V pyramidal neurons in visual cortices of Fmr1 KO and wildtype (WT) mice bred in a C57BL/6 background. We report that spine abnormalities in these animals parallel abnormalities reported in humans with FXS, perhaps to a greater degree than KO mice bred in an FVB background. Specifically, Fmr1 KO mice bred in a C57BL/6 background exhibited significantly more longer dendritic spines and fewer shorter spines, as well as more spines with immature-appearing morphology and fewer with mature-appearing morphology than WT littermates. Spine length abnormalities were demonstrated to be largely independent of spine morphology abnormalities, as the length phenotype was observed in KOs even within a morphological category. Fmr1 KO mice also had a greater overall spine density than WTs. These findings provide powerful support for the essence of the dendritic spine abnormalities in the absence of FMRP, now found to be largely consistent with human data across two mouse backgrounds.     

Learning causes synaptogenesis, whereas motor activity causes angiogenesis, in cerebellar cortex of adult rats.

The role of the cerebellar cortex in motor learning was investigated by comparing the paramedian lobule of adult rats given difficult acrobatic training to that of rats that had been given extensive physical exercise or had been inactive. The paramedian lobule is activated during limb movements used in both acrobatic training and physical exercise. Acrobatic animals had greater numbers of synapses per Purkinje cell than animals from the exercise or inactive groups. No significant difference in synapse number or size between the exercised and inactive groups was found. This indicates that motor learning required of the acrobatic animals, and not repetitive use of synapses during physical exercise, generates new synapses in cerebellar cortex. In contrast, exercise animals had a greater density of blood vessels in the molecular layer than did either the acrobatic or inactive animals, suggesting that increased synaptic activity elicited compensatory angiogenesis.     

烧伤大鼠早期胃肠喂养的实验研究

目的：探讨严重烧伤后早期胃肠性喂养的作用及方法。方法：对伤后２小时既开始喂养的严重烧伤大鼠进行血浆蛋白监测,并与正常大鼠及伤后禁食大鼠作对比。结果：喂养组大鼠伤后７天血浆球蛋白明显上升至接近正常,胃肠粘膜病理变化减轻。结论：早期喂养有减轻胃肠及全身损害的作用。     

MEBT/MEBO治愈夫妻面部烧伤的护理体会

目的：介绍夫妻二人同时面部酒精火焰烧伤后,用ＭＥＢＯ治愈护理的体会。方法：采用ＭＥＢＴ／ＭＥＢＯ、创面与心理护理等方法,并总结了经验与才识结果：ＭＥＢＴ／ＭＥＢＯ对颜面部浅Ⅱ度和深Ⅱ度创面有止痛效果,愈合快,无明显疤痕及色素沉着。结论：ＭＥＢＴ／ＭＥＢＯ对颜面部Ⅱ度烧伤创面是最适宜的治疗方法。     

Neuropeptide Release Is Impaired in a Mouse Model of Fragile X Mental Retardation Syndrome

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Lung function abnormalities at 6 months of age after neonatal intensive care.

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Randomised controlled trial of two methods of weaning from high frequency positive pressure ventilation.

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