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1.
Benign paroxysmal torticollis is probably an under‐diagnosed condition of infancy. It is a self‐limiting disorder characterised by periods of unusual, sustained posture of the head and neck, during which the head tilts to one side. Episodes are often accompanied by marked autonomic features, irritability, ataxia, apathy and drowsiness. They last several hours to a few days and are often recurring every few weeks. They subside within the pre‐school years; however, during later childhood, there is a tendency to develop migraine. Three cases of benign paroxysmal torticollis are presented and are compared with cases in the literature. A telephone survey has been conducted to determine what is the general awareness of paediatricians of this condition in Cyprus. Eighty‐two paediatricians were randomly selected out of 235 paediatricians. All of them agreed to participate. Our cases revealed that benign paroxysmal torticollis may coexist with other problems during infancy. The telephone survey showed that only two out of eighty‐two (2.4%) of the paediatricians are aware of the condition, and none of them was confident regarding the management. Our telephone survey clearly shows that Cypriot paediatricians are not familiar with benign paroxysmal torticollis in infancy which is a benign, self‐limiting disorder. It is essential to recognise the condition and to reassure parents of its benign course and not to be misdiagnosed for other disorders, such as epileptic seizures. We have shown again that benign paroxysmal torticollis in infancy may coexist with motor delay and hearing problems.  相似文献   
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Cell adhesion molecule cadherins play important roles in both development and maintenance of adult structures. Most studies on cadherin expression have been carried out in developing organisms, but information on cadherin distribution in adult vertebrate brains is limited. In this study we used in situ hybridization to examine mRNA expression of three cadherins, protocadherin‐19, protocadherin‐17, and cadherin‐6 in adult zebrafish brain. Each cadherin exhibits a distinct expression pattern in the fish brain, with protocadherin‐19 and protocadherin‐17 showing much wider and stronger expression than that of cadherin‐6. Both protocadherin‐19 and protocadherin‐17‐expressing cells occur throughout the brain, with strong expression in the ventromedial telencephalon, periventricular regions of the thalamus and anterior hypothalamus, stratum periventriculare of the optic tectum, dorsal tegmental nucleus, granular regions of the cerebellar body and valvula, and superficial layers of the facial and vagal lobes. Numerous sensory structures (e.g., auditory, gustatory, lateral line, olfactory, and visual nuclei) and motor nuclei (e.g., oculomotor, trochlear, trigeminal motor, abducens, and vagal motor nuclei) contain protocadherin‐19 and/or protocadherin‐17‐expressing cell. Expression of these two protocadherins is similar in the ventromedial telencephalon, thalamus, hypothalamus, facial, and vagal lobes, but substantially different in the dorsolateral telencephalon, intermediate layers of the optic tectum, and cerebellar valvula. In contrast to the two protocadherins, cadherin‐6 expression is much weaker and limited in the adult fish brain. J. Comp. Neurol. 523:1419–1442, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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We studied the afferent connections of two cytoarchitectural subdivisions of the caudolateral frontal cortex, areas 6Va and 8C, in marmoset monkeys. These areas received connections from the same set of thalamic nuclei, including main inputs from the ventral lateral and ventral anterior complexes, but differed in their patterns of corticocortical connections. Areas 8C and 6Va had reciprocal interconnections, and received similar proportions of afferents from premotor areas 6M and 6DC, and from the prefrontal cortex. However, area 8C received stronger inputs from frontal areas that have been implicated in oculomotor functions, whereas area 6Va received stronger projections from the primary motor area. Somatosensory projections to area 6Va were generally stronger than those to area 8C, and originated from several areas; in contrast, only the second somatosensory area (S2) sent major inputs to area 8C. Finally, although both 6Va and 8C received major inputs from the rostral posterior parietal cortex (putative homologs of areas PE, PF, and PFG), area 8C also received a variety of smaller connections from posterior midline, caudal posterior parietal, and extrastriate areas. Statistical analyses revealed that the pattern of connections of area 8C is more akin to that characterizing a premotor area, rather than a prefrontal area. We conclude that cytoarchitectural area 6Va in the marmoset is similar to ventral premotor areas identified in other simian primates, and that area 8C corresponds to a specialized subdivision of the caudal premotor complex where visual information for the guidance of movements is likely to be emphasized. J. Comp. Neurol. 523:1222–1247, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
5.
Tooth loss is common, and exploring the neuroplastic capacity of the face primary motor cortex (face‐M1) and adjacent primary somatosensory cortex (face‐S1) is crucial for understanding how subjects adapt to tooth loss and their prosthetic replacement. The aim was to test if functional reorganization of jaw and tongue motor representations in the rat face‐M1 and face‐S1 occurs following tooth extraction, and if subsequent dental implant placement can reverse this neuroplasticity. Rats (n = 22) had the right maxillary molar teeth extracted under local and general anesthesia. One month later, seven rats had dental implant placement into healed extraction sites. Naive rats (n = 8) received no surgical treatment. Intracortical microstimulation (ICMS) and recording of evoked jaw and tongue electromyographic responses were used to define jaw and tongue motor representations at 1 month (n = 8) or 2 months (n = 7) postextraction, 1 month postimplant placement, and at 1–2 months in naive rats. There were no significant differences across study groups in the onset latencies of the ICMS‐evoked responses (P > 0.05), but in comparison with naive rats, tooth extraction caused a significant (P < 0.05) and sustained (1–2 months) decreased number of ICMS‐defined jaw and tongue sites within face‐M1 and ‐S1, and increased thresholds of ICMS‐evoked responses in these sites. Furthermore, dental implant placement reversed the extraction‐induced changes in face‐S1, and in face‐M1 the number of jaw sites even increased as compared to naive rats. These novel findings suggest that face‐M1 and adjacent face‐S1 may play a role in adaptive mechanisms related to tooth loss and their replacement with dental implants. J. Comp. Neurol. 523:2372–2389, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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Motor commands computed by the cerebellum are hypothesized to use corollary discharge, or copies of outgoing commands, to accelerate motor corrections. Identifying sources of corollary discharge, therefore, is critical for testing this hypothesis. Here we verified that the pathway from the cerebellar nuclei to the cerebellar cortex in mice includes collaterals of cerebellar premotor output neurons, mapped this collateral pathway, and identified its postsynaptic targets. Following bidirectional tracer injections into a distal target of the cerebellar nuclei, the ventrolateral thalamus, we observed retrogradely labeled somata in the cerebellar nuclei and mossy fiber terminals in the cerebellar granule layer, consistent with collateral branching. Corroborating these observations, bidirectional tracer injections into the cerebellar cortex retrogradely labeled somata in the cerebellar nuclei and boutons in the ventrolateral thalamus. To test whether nuclear output neurons projecting to the red nucleus also collateralize to the cerebellar cortex, we used a Cre‐dependent viral approach, avoiding potential confounds of direct red nucleus‐to‐cerebellum projections. Injections of a Cre‐dependent GFP‐expressing virus into Ntsr1‐Cre mice, which express Cre selectively in the cerebellar nuclei, retrogradely labeled somata in the interposed nucleus, and putative collateral branches terminating as mossy fibers in the cerebellar cortex. Postsynaptic targets of all labeled mossy fiber terminals were identified using immunohistochemical Golgi cell markers and electron microscopic profiles of granule cells, indicating that the collaterals of nuclear output neurons contact both Golgi and granule cells. These results clarify the organization of a subset of nucleocortical projections that constitute an experimentally accessible corollary discharge pathway within the cerebellum. J. Comp. Neurol. 523:2254–2271, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
7.
Introduction: The aim of this study was to localize the motor entry point (MEP) of the thyroarytenoid muscle. Methods: Eight cadaver larynges were dissected. A virtual plane was used to represent the MEP in a coordinate (X/Y/Z) system. The inferior border of the thyroid cartilage was linked to the center of the anterior arc of the cricoid cartilage (the Y‐axis). The X‐axis was set perpendicular to the Y‐axis; the Z‐axis passed through the posterior border of the thyroid lamina from the height of the insertion point. Results: The mean X, Y, and Z coordinates were 6.2 mm, 9.1 mm, and 11.0 mm, respectively. The calculated angles of the lateral and superior deflections were 29.4° and 35.8°, respectively. The calculated insertion depth, that is, the distance from the insertion point to the MEP, was 15.6 mm. Conclusions: These results may help to improve the accuracy of needle insertion during diagnostic laryngeal electromyography or laryngeal electromyography‐guided injections. Muscle Nerve 51 : 72–75, 2015  相似文献   
8.
Introduction: The motor unit number index (MUNIX) refers to an electrophysiological method that measures the number of motor units in the surface electromyographic interference pattern (SIP) recorded during graded muscle contractions. MUNIX studies of limb muscles have been conducted, but MUNIX studies of bulbo‐facial muscles have not been reported. Methods: We assessed bilateral orbicularis oculi muscles using MUNIX, and the reference values and reproducibility of MUNIX and motor unit size index (MUSIX) were investigated in healthy subjects. Results: In this study, MUNIX was applied successfully to the orbicularis oculi muscles and showed good reproducibility. The correlation coefficients for MUNIX and MUSIX were 0.803 and 0.592, respectively, and the coefficients of variation were 20.9% and 8.5%, respectively. Conclusions: The MUNIX procedure for the orbicularis oculi muscle would be a useful tool for evaluating bulbar symptoms, especially in amyotrophic lateral sclerosis. Muscle Nerve 51 : 197–200, 2015  相似文献   
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Introduction: With clinical trials underway, our objective was to construct a composite score of global function that could discriminate among people with spinal muscular atrophy (SMA). Methods: Data were collected from 126 participants with SMA types 2 and 3. Scores from the Hammersmith Functional Motor Scale—Expanded and Upper Limb Module were expressed as a percentage of the maximum score and 6‐minute walk test as percent of predicted normal distance. A principal component analysis was performed on the correlation matrix for the 3 percentage scores. Results: The first principal component yielded a composite score with approximately equal weighting of the 3 components and accounted for 82% of the total variability. The SMA functional composite score, an unweighted average of the 3 individual percentage scores, correlated almost perfectly with the first principal component. Conclusions: This combination of measures broadens the spectrum of ability that can be quantified in type 2 and 3 SMA patients. Muscle Nerve 52 : 942–947, 2015  相似文献   
10.
Introduction: In this study we aimed to characterize muscle composition of the medial gastrocnemius in children with spastic cerebral palsy (SCP) using quantitative ultrasound. Methods: Forty children with SCP, aged 4–14 years, participated in this study. Children were grouped according to the gross motor function classification system (GMFCS I–V) and compared with a cohort of age‐ and gender‐matched, typically developing children (TD; n = 12). Ultrasound scans were taken of the medial gastrocnemius. Images were then characterized using grayscale statistics to determine mean echo intensity (EI) and the size and number of spatially connected homogeneous regions (i.e., blobs). Results: Significant differences in skeletal muscle composition were found between children with SCP and their TD peers. Children classified as GMFCS III consistently exhibited the highest EI and blob area. Conclusions: This study demonstrates altered tissue composition in children with SCP visualized using ultrasound. Further work is required to determine the pathophysiology contributing to these alterations in SCP. Muscle Nerve 52:397–403, 2015  相似文献   
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