Respiratory Failure Secondary to Diaphragmatic Paralysis from Acute Exacerbation of Dermatomyositis

Dermatomyositis (DM) is an idiopathic inflammatory disorder that presents with proximal muscle weakness and typical DM skin changes. DM can involve other organs such as the lung, esophagus, and heart. Diaphragmatic muscle paralysis is an unrecognized clinical presentation of acute DM exacerbation. A 58-year-old man with a history of DM presented to the hospital after sustaining a cardiorespiratory arrest. Before arrest, he had been suffering from progressive dyspnea and muscle weakness. Immunosuppressive therapy of tacrolimus for DM was recently discontinued due to renal toxicity. Bedside ultrasound of the diaphragm while intubated revealed evidence of bilateral diaphragmatic paralysis. After extubation, supine and upright pulmonary function tests (PFT) and sniff test results strengthened the diagnosis of diaphragmatic paralysis. The patient was worked up for an acute DM exacerbation as the likely etiology of the severe diaphragmatic muscle weakness (diaphragmatic paralysis) and ventilatory failure. Skin and muscle biopsy confirmed the diagnosis of active DM. The patient was treated with high dose steroids and mycophenolate mofetil, following which he soon recovered.     

The false premise in measuring body-support interface pressures for preventing serious pressure ulcers

Presently, commercial cushioning products for pressure ulcer prevention are being evaluated for their protective effect exclusively based on interfacial pressures between the cushion/mattress and the patient. However, interface pressures cannot predict elevated mechanical stresses in deep tissues adjacent to bony prominences. Such deep tissue stress concentrations are associated with local ischaemia and hypoxia, which over time result in deep tissue necrosis, particularly of muscle tissue. In order to demonstrate this phenomenon, a physical phantom of the mechanical interaction between the ischial tuberosities (IT) and gluteus muscles of the buttocks was built, incorporating geometric replica of the human IT and real (bovine) muscle tissue. Internal muscle stresses directly under the IT were five to 11-fold greater than stresses at more distal locations, and a Pearson correlation test showed that they could not have been predicted from the interface pressures in the phantom. Accordingly, though pressure ulcer prevention clinics which utilize routine sitting pressure measurements report effective outcomes, the present results highlight a problem in using body-support pressure measurements to predict the risk for pressure-related deep tissue injury.     

低钾型周期性麻痹急诊处理体会(附96例报告)

目的探讨低钾型周期性麻痹(hypokalemic periodic paralysis.HOPP)的诱发因素、临床表现及诊治体会.方法回顾性分析96例HOPP患者的临床资料.结果发病前常有明显诱因,发病多在夜间睡眠中或凌晨清醒后.最早表现为四肢不同程度的迟缓性的肌无力,部分重度HOPP患者可并发心律失常及呼吸肌麻痹,急诊心电图检查发现所有病例均有典型T波改变.95例患者经静脉及口服补钾,配合安体舒通、硫酸镁治疗后症状完全缓解,1例重度患者死于休克和严重心率失常.结论对于HOPP,及早诊治是关键;而对于重度HOPP,心电监护、抗心率失常药物、抗休克治疗和呼吸机辅助呼吸是抢救成功的重要措施.     

家族性高钾型周期性麻痹的SCN4A基因突变

目的　筛查1个高钾型周期性麻痹(hyperkalemicperiodicparalysis, hyperKPP)家系的SCN4A基因,明确该病与SCN4A基因的关系。方法　总结1个hyperKPP家系中7例患者的临床特点,应用变性液相色谱(denaturinghighperformanceliquidchromatography,DHPLC)技术筛查SCN4A基因全部24个外显子,对发现异常洗脱峰者进行连锁分析并测序。结果　该家系具有典型hyperKPP临床特征,但无肌强直。先证者经DHPLC筛查发现在外显子13、23及24存在杂合二倍体。测序及连锁分析证实位于外显子13的碱基替换引起氨基酸序列改变(Thr704Met);外显子23的碱基替换虽引起氨基酸序列改变(Asp1376Asn)与疾病连锁,但进一步研究显示其为一良性多态;外显子24的碱基替换为同义突变。结论　该家族性hyperKPP与SCN4A基因相关,并由最常见的突变Thr704Met引起。     

减重平板训练对瘫痪后步行障碍患者的影响

目的：观察减重平板训练对脊髓损伤和脑损伤造成的长期下肢瘫痪步行功能的作用。方法：10名男性患者，年龄25－64岁，其中4例脊髓损伤，6例脑血管意外，病程平均1．4年，减重平板训练前均接受不同程度的传统康复训练，功能步行评定为0－1分，接受减重平板训练每天1次，开始减重重量在50％－70％之间，平板速度为0．27m/s，平均20次，所有虱训练前后接受功能步行和一般平衡功能测定，其中7例患者在Kistler压电晶体式三维测力台上进行步态分析。结果：患者经过阶段性减重平板训练，功能性步行评定及站立平衡功能比传统康复治疗前后有十分明显的改善（P＜0．0001，P＝0．0003），其中7例患者的平均步速达0．36m/s，左右足对台压力峰值和支撑时间无明显差异（P＞0．05），结论：减重平板训练对长期瘫痪患者改善步行能力有帮助。     

自体MSC-NSCs治疗小儿急性播散性脑脊髓炎后瘫痪1例

目的观察自体骨髓间充质干细胞转化神经干细胞移植对急性播散性脑脊髓炎后下肢瘫痪的治疗效果。方法采集自体骨髓分离间充质干细胞体外培养增殖后诱导为神经干细胞后移植给患儿。结果患儿下肢的功能明显恢复。结论自体骨髓间充质干细胞转化神经干细胞移植是急性播散性脑脊髓炎后下肢瘫痪的有效方法。     

The effect of ageing in spinal cord injured humans on the blood pressure and heart rate responses during fatiguing isometric exercise

Groups of 50 healthy male controls and 50 subjects suffering from paraplegia (aged 20–65 years) were examined as to the inter-relationships between age, paraplegia and the strength, endurance, blood pressure and heart rate responses to fatiguing isometric exercise. Contractions were maintained in both groups under voluntary effort and through a contraction induced by electrical stimulation in the paraplegic group. All contractions were maintained to fatigue at a tension of 40% of the maximal muscle strength in either the handgrip or quadriceps muscles. Muscle strength of the handgrip was higher in the paraplegic subjects than in the controls, averaging 589 N and 463 N, respectively for the two groups. In contrast, quadriceps leg extension strength averaged 696 N in the controls and 190 N in the paraplegic groups; for both groups, ageing was associated with a reduction in muscle strength. While leg endurance was less in the paraplegic group than the control group, handgrip endurance was similar in the two groups, endurance increasing with ageing in both the controls and paraplegics. Both systolic and diastolic blood pressures increased at rest in paraplegic and control subjects with age. The magnitude of the pressor response to exercise also increased with age. This was true during both voluntary exercise and exercise induced through electrical stimulation in the paraplegic groups. The heart rate response (change in heart rate during exercise) to a fatiguing isometric handgrip contraction decreased by about 50% between the ages of 20 and 60 years in both the controls and paraplegics for isometric handgrip exercise. In contrast, heart rate changed little with age during contractions of the quadriceps muscle in paraplegics which were induced by electrical stimulation. Electronic Publication     

Differential skeletal muscle gene expression after upper or lower motor neuron transection

Causes of disuse atrophy include loss of upper motor neurons, which occurs in spinal cord injury (SCI) or lower motor neurons (denervation). Whereas denervation quickly results in muscle fibrillations, SCI causes delayed onset of muscle spasticity. To compare the influence of denervation or SCI on muscle atrophy and atrophy-related gene expression, male rats had transection of either the spinal cord or sciatic nerve and were sacrificed 3, 7, or 14 days later. Rates of atrophy increased gradually over the first week after denervation and then were constant. In contrast, atrophy after SCI peaked at 1 week, then declined sharply. The greater atrophy after SCI compared to denervation was preceded by high levels of ubiquitin ligase genes, MAFbx and MuRF1, which then also markedly declined. After denervation, however, expression of these genes remained elevated at lower levels throughout the 2-week time course. Interestingly, expression of the muscle growth factor, IGF-1 was increased at 3 days after denervation when fibrillation also peaks compared to SCI. Expression of IGF-1R, GADD45, myogenin, and Runx1 were also initially increased after denervation or SCI, with later declines in expression levels which correlated less well with rates of atrophy. Thus, there were significant time-dependent differences in muscle atrophy and MAFbx, MuRF1, and IGF-1 expression following SCI or denervation which may result from distinct temporal patterns of spontaneous muscle contractile activity due to injury to upper versus lower motor neurons.