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61.
Identifying frontal impairment in ALS is an important goal albeit disease-dedicated tools are still scarce. For this reason, we decided to consider primitive reflexes (PRs), variably regarded as correlates of frontal release and/or of upper motor neuron (UMN) impairment, often in the setting of dementias. Specifically, the aims of this work consisted in assessing the exact prevalence of the combination of seven PRs in ALS, trying to clarify their role as putative proxies of cognitive impairment or of UMN dysfunction. In this cross-sectional study, 50 consecutive ALS outpatients were evaluated for the presence of: palmomental (PM), corneomandibular (CM), glabella tap (MY), rooting, sucking, snout, and grasping reflexes. Cognitive screening was performed by the Frontal Assessment Battery (FAB) and the Weigl’s Sorting test (WST); UMN dysfunction was concomitantly evaluated. PM, CM and MY were more frequently detected (62, 52, and 44 % of the ALS sample, respectively), while the other reflexes were under-represented. Patients displaying three or more PRs had significantly lower FAB and WST scores. On the other hand, UMN dysfunction was only moderately associated to PRs. In conclusion, PRs’ assessment is a promising complementary tool for screening cognitive impairment in ALS; however, further work will be necessary to establish its added value with respect to already existing ALS-dedicated screening tools for cognition.  相似文献   
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We have prepared thyroid follicles in suspension culture to use as a model system in vitro for investigation of some properties of the thyroid gland. The follicles were free of endothelial cells, fibroblasts, and other nonepithelial cells. They were prepared by collagenase treatment of minced rat thyroid glands followed by differential filtration of the suspension through nylon meshes. Small clusters of principal thyroid epithelial cells were separated from large fragments and single cells. They were cultured in dilute suspension in Coon's modified F-12 medium in dishes coated with agarose to avoid having the cells attach to the dishes. By culture day 3, most of the clusters formed closed follicles containing a periodic acid-Schiff-positive colloid but without a basal lamina. Follicle walls contained an occasional C cell. The epithelium resembled that in the thyroid of a recently hypophysectomized rat, with normal polarity and organelle complement normal with respect to position and abundance, with basally located lysosomes, no pseudopods, and no colloid droplets. The cells were responsive to thyroid-stimulating hormone (thyrotropin) and to dibutyryl cyclic AMP. Thyroid-stimulating hormone at 10 munits/ml resulted in apical migration of lysosomes and formation of pseudopods and colloid droplets within 30 min; longer exposure resulted in depletion of luminal colloid. The results indicate that the suspended follicles resemble follicles in vivo with respect to morphology and responsiveness to thyroid-stimulating hormone in the absence of other cell types.  相似文献   
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Journal of Neuroimmune Pharmacology - Lentiviruses are retroviruses that primarily infect myeloid cells, leading to acute inflammatory infections in many tissues particularly, lung, joints and the...  相似文献   
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Since the first cases of abnormal paroxystic movements in normal infants were described, the importance of accurate characterization of this medical condition has been increasingly confirmed in the literature. Non‐epileptic attacks mimic epileptic paroxysms in clinical presentation, but they have a typically benign course and are unresponsive to pharmacological treatment. An evident feature of the syndrome is its extreme variability in clinical manifestation. Here, we describe three normal infants with two similar forms of non‐epileptic paroxysms. Electroclinical manifestations and profile of evolution were investigated. Ictal video‐EEG polygraphic recordings were obtained for each patient. The increasing number of such reported clinical cases in the literature may contribute to high quality systematic reviews and the development of useful guidelines in the future. The clinical heterogeneity of non‐epileptic attacks, together with the relative rarity of the condition, may make differential diagnosis with epileptic attacks very challenging. [Published with video sequences]  相似文献   
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Adult patients with Niemann-Pick disease type C (NPC) usually develop cognitive impairment progressing to dementia, whose pathophysiology remains still unclear. Noteworthy parallels exist in cognitive impairment and cellular pathology of NPC and Alzheimer’s disease (AD). In particular, alterations of cholinergic system, which represent one of the pathological hallmarks and contribute to cognitive deterioration in AD, have recently been demonstrated in a human brain autopsy and in an experimental model of NPC. This finding raised the issue that central cholinergic circuits dysfunction may contribute to pathophysiology of cognitive impairment in NPC as well, and prompted us to evaluate the cholinergic functional involvement in NPC patients by applying a neurophysiologic technique, named short-latency afferent inhibition (SAI). We describe clinical, biochemical, molecular and neuropsychological features, and SAI findings in three patients affected by NPC. Diagnosis of NPC was assessed by molecular analysis of the NPC1 gene in all patients. In two of them, biochemical analysis of intracellular accumulation of unesterified cholesterol was also performed. The main clinical features were cerebellar ataxia, vertical supranuclear gaze palsy and a variable degree of cognitive impairment ranging from only memory impairment to severe dementia. Electrophysiological evaluation revealed a reduced SAI in all three patients. Our SAI findings provide evidence of cholinergic dysfunction in patients with the adult form of NPC, supporting that cholinergic alterations may play a role in cognitive impairment in NPC, and strengthening the similarities between NPC and AD.  相似文献   
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