TRPM4 channels couple purinergic receptor mechanoactivation and myogenic tone development in cerebral parenchymal arterioles

Cerebral parenchymal arterioles (PAs) have a critical role in assuring appropriate blood flow and perfusion pressure within the brain. They are unique in contrast to upstream pial arteries, as defined by their critical roles in neurovascular coupling, distinct sensitivities to chemical stimulants, and enhanced myogenic tone development. The objective of the present study was to reveal some of the unique mechanisms of myogenic tone regulation in the cerebral microcirculation. Here, we report that in vivo suppression of TRPM4 (transient receptor potential) channel expression, or inhibition of TRPM4 channels with 9-phenanthrol substantially reduced myogenic tone of isolated PAs, supporting a key role of TRPM4 channels in PA myogenic tone development. Further, downregulation of TRPM4 channels inhibited vasoconstriction induced by the specific P2Y4 and P2Y6 receptor ligands (UTPγS and UDP) by 37% and 42%, respectively. In addition, 9-phenanthrol substantially attenuated purinergic ligand-induced membrane depolarization and constriction of PAs, and inhibited ligand-evoked TRPM4 channel activation in isolated PA myocytes. In concert with our previous work showing the essential contributions of P2Y4 and P2Y6 receptors to myogenic regulation of PAs, the current results point to TRPM4 channels as an important link between mechanosensitive P2Y receptor activation and myogenic constriction of cerebral PAs.     

What lies beneath: A comparison of reading aloud in pure alexia and semantic dementia

Exaggerated effects of word length upon reading-aloud performance define pure alexia, but have also been observed in semantic dementia. Some researchers have proposed a reading-specific account, whereby performance in these two disorders reflects the same cause: impaired orthographic processing. In contrast, according to the primary systems view of acquired reading disorders, pure alexia results from a basic visual processing deficit, whereas degraded semantic knowledge undermines reading performance in semantic dementia. To explore the source of reading deficits in these two disorders, we compared the reading performance of 10 pure alexic and 10 semantic dementia patients, matched in terms of overall severity of reading deficit. The results revealed comparable frequency effects on reading accuracy, but weaker effects of regularity in pure alexia than in semantic dementia. Analysis of error types revealed a higher rate of letter-based errors and a lower rate of regularization responses in pure alexia than in semantic dementia. Error responses were most often words in pure alexia but most often nonwords in semantic dementia. Although all patients made some letter substitution errors, these were characterized by visual similarity in pure alexia and phonological similarity in semantic dementia. Overall, the data indicate that the reading deficits in pure alexia and semantic dementia arise from impairments of visual processing and knowledge of word meaning, respectively. The locus and mechanisms of these impairments are placed within the context of current connectionist models of reading.     

On the anisotropy of skeletal muscle tissue under compression

This paper deals with the role of the muscle fibres and extracellular matrix (ECM) components when muscle tissue is subjected to compressive loads. To this end, dissected tissue samples were tested in compression modes which induced states of fibres in compression (I), in tension (II) or at constant length (III), respectively. A comparison of the stress responses indicated that the tissue behaviour is significantly different for these modes, including differences between the modes (I) and (III). This contradicts the paradigm of many constitutive models that the stress response can be decomposed into an isotropic part relating to the ECM and an anisotropic fibre part the contribution of which can be neglected under compression. Conversely, the results provide experimental evidence that there is an anisotropic contribution of the fibre direction to the compressive stress. Interpreting these results in terms of recent microscopical studies, potential connections between the observed behaviour and the structure of muscle ECM are established.     

影响纯音听阈测定的因素和对策

目的了解影响纯音听阈测定的因素,尽可能地减少或消除可变因素的影响,提高听闽测定结果的准确性.方法通过了解影响纯音听阈测定的多种因素并加以注意,掌握正确的测听方法.结果纯音听阈测定的准确性会更高.     

浅探五音补泻

五行音乐调式属性特点各具风格,主治及代表曲目各不相同.然五音调式的应用尚无统一标准,五音补泻是五行音乐发挥疗效的关键,如何应用五音进行补泻对五行音乐临床运用具有重要意义.文章在“五音疗疾”理论基础上,探讨了脏腑虚实、情绪状态、体质因素对五音疗效的影响,分析了五音的脏腑补泻、情志补泻及体质补泻,提出了五音不同调式乐曲对五...     

True thymic hyperplasia causing pure red cell aplasia: a case report

Pure red cell aplasia caused by true thymic hyperplasia is extremely rare. We report the case of a 25-year-old female diagnosed with pure red cell aplasia. Following a thymectomy confirming true thymic hyperplasia and corticosteroid therapy, complete response was achieved. Patients diagnosed with pure red cell aplasia should be investigated with a computerized tomographic scan to assess for thymic pathology and if present, this should be resected. Follow-up is essential to monitor for recurrence.     

神经肌肉关节促进法对脑梗死偏瘫患者下肢肌张力的影响

目的 探讨神经肌肉关节促进法（NJF）对脑梗死偏瘫患者下肢肌张力的治疗作用及效果。方法 收集脑梗死患者136例,根据是否使用NJF治疗分为治疗组（66例）与对照组（70例）。分别在治疗前、治疗10 d后采用改良Ashworth量表评定2组患者偏瘫侧的下肢肌张力,Brunnstrom分期评定2组患者偏瘫侧下肢运动功能,根据转移时所需帮助量的程度评定患者的转移能力（包括卧坐转移、坐站转移）,Bobath法平衡功能评定患者平衡能力,Holden功能性步行量表评定患者步行能力。结果 治疗10 d后治疗组患者下肢高肌张力降低比例为21.2%,高于对照组的1.4%(P <0.001);治疗组患者坐站转移能力好转比例为47.0%,高于对照组的27.1%(P <0.05)。结论 NJF治疗有利于降低脑梗死偏瘫患者下肢的高肌张力,使其趋于正常水平,有助提高其坐站转移能力。     

高压性小脑出血的外科治疗

目的探讨外科手术治疗高压性小脑出血的疗效。方法分别采取单纯后颅凹减压术和后颅凹减压加侧脑室外引流治疗高压性小脑出血。结果28例行单纯后颅凹减压术,9例行后颅凹减压加侧脑室外引流术,血肿清除90%以上30例,70%以上7例,无再出血病例。治愈22例,好转10例,死亡5例。结论小脑出血病情凶险,积极手术可取得良好的治疗效果。     

Protective role of endothelial nitric oxide synthase

Nitric oxide is a versatile molecule, with its actions ranging from haemodynamic regulation to anti-proliferative effects on vascular smooth muscle cells. Nitric oxide is produced by the nitric oxide synthases, endothelial NOS (eNOS), neural NOS (nNOS), and inducible NOS (iNOS). Constitutively expressed eNOS produces low concentrations of NO, which is necessary for a good endothelial function and integrity. Endothelial derived NO is often seen as a protective agent in a variety of diseases.This review will focus on the potential protective role of eNOS. We will discuss recent data derived from studies in eNOS knockout mice and other experimental models. Furthermore, the role of eNOS in human diseases is described and possible therapeutic intervention strategies will be discussed.     

Neurophysiology of hearing in patients with mucopolysaccharidosis type IV

Background

Hearing impairment is a common problem in patients with mucopolysaccharidosis IV (MPS IV) throughout their life. Many of the adult patients with MPS IV exhibit permanent or severe hearing loss. However, there has been no systematic review of detailed audiological test results in MPS IV.