Diffusion-weighted MRI and the evaluation of spinal cord axonal integrity following injury and treatment

Diffusion-based magnetic resonance imaging (MRI) (DWI) has been shown experimentally to detect both injury and functionally significant neuroprotection of injured spinal cord white matter that would otherwise go undetected with conventional MRI techniques. The diffusion of water in the central nervous system (CNS) is thought to be affected by both its location (intracellular or extracellular), and by diffusion barriers formed by cell membranes and myelin sheaths. There is, however, controversy concerning how to obtain, interpret, and present DWI data. Computer simulations and MR microscopy have been helpful in resolving some of these issues, as well as determining exact histologic correlates to DWI findings.     

1例重型弥漫性轴索损伤伴肺挫裂伤患者的肺康复护理

总结1例重型弥漫性轴索损伤伴肺挫裂伤患者的肺康复护理经验。护理要点包括：组建多学科肺康复管理团队,实施个性化呼吸支持与降阶梯序贯氧疗护理,精准廓清呼吸道,开展一体化的早期肺功能康复锻炼。经过多学科团队合作,患者入院后第12天撤离呼吸机,第17天拔除气管插管,第20天下床活动,第37天顺利出院,随访6个月,患者恢复良好。     

肝良恶性肿瘤包膜回缩征影像表现及其病理基础

目的：探讨肝良恶性肿瘤引起包膜回缩征的CT和MRI表现及其病理基础。方法：回顾性分析经病理证实 的50例肝良恶性肿瘤肝包膜回缩征的CT和MRI表现及病理特点。通过影像归档和通信系统观察、比较包膜下肝良恶 性肿瘤形态、大小及肝包膜回缩宽度、深度、边缘情况、肝包膜下是否有积液的异同,显微镜下分析肿瘤内部及周 围结构、分化程度及纤维组织增生量。结果：肝恶性肿瘤44例,良性肿瘤6例。良性肿瘤与高、中、低三个不同分化 等级的恶性肿瘤肝包膜回缩边缘光整或毛糙差异有统计学意义(均P<0.05)。纤维组织增生量不同的肿瘤肝包膜回缩 宽度、深度差异有统计学意义(均P<0.05)。肿瘤直径大小与肝包膜回缩宽度、深度呈正相关(分别r=0.557,0.309,均 P<0.05)。结论：肝良恶性肿瘤均可出现肝包膜回缩征,但两者形态有差异,与肿瘤大小、分化程度及瘤内纤维组织 增生程度等密切相关。     

多发性硬化、临床孤立综合征患者脑脊液β-淀粉样肽水平及其意义研究

目的 探讨多发性硬化(MS)及其早期表现-临床孤立综合征(CIS)患者脑脊液β-淀粉样肽(Aβ42)表达水平及其与病程、神经功能缺失以及MRI T2高信号病灶数量的关系.方法 对33例MS患者、23例CIS患者及13例对照者进行研究,MS、CIS患者发作期进行扩展残疾状态量表(EDSS)评分及MRI检查,采用液相芯片分析技术检测各组患者脑脊液Aβ42浓度.结果 MS、CIS患者发作期脑脊液Aβ42浓度与对照组相比差异无统计学意义(P>0.05),但继发进展型MS(SPMS)患者脑脊液Aβ42浓度[(167.99±36.39)pg/mL]比复发缓解型MS(RRMS)患者[(92.74±13.64)pg/mL]高,差异有统计学意义(P=0.042).MS、CIS患者脑脊液Aβ42浓度与病程及EDSS评分无明显相关性(P>0.05).病程≥1年的MS患者脑脊液Aβ42浓度比病程<1年的患者低,EDSS评分≥4.5分的MS、CIS患者脑脊液Aβ42浓度比EDSS评分<4.5分的患者低,但差异均无统计学意义(P>0.05).MS、CIS患者脑脊液Aβ42浓度与MRI T2高信号病灶数量呈正相关关系(MS患者:r=0.507.P=0.038;CIS患者:r=0.485,P=0.049).MRI T2高信号病灶总数≥4个的MS患者脑脊液Aβ42浓度[(129.34±19.96)pg/mL]比病灶总数<4个的MS患者[(73.51±12.60)pg/mL]高,差异有统计学意义(P=0.049).结论 SPMS患者轴突损伤比RRMS患者严重;脑脊液Aβ42水平升高可能是MS病情进展的标记之一;MRI T2高信号病灶负荷可能与MS轴突损伤有关.     

An autopsy case of acute porphyria with a decrease of both uroporphyrinogen I synthetase and ferrochelatase activities

Summary An autopsy case of a 37-year-old woman with acute porphyria is reported. The patient began to complain of severe menstrual pains, and later developed serious peripheral neuropathy and various autonomic nervous symptoms.The autopsy revealed a marked loss and degeneration of axons and myelin sheaths in the peripheral nervous system (PNS), and prominent central chromatolysis of the spinal anterior horn cells. The predominant process of the peripheral neuropathy appeared to be axonal degeneration.Biochemical analysis showed a marked increase of delta-aminolevulinic acid (ALA), porphobilinogen, uroporphyrin, and coproporphyrin in the urine, and an increase of coproporphyrin and protoporphyrin in the stools and blood. In the analysis of the enzymatic activities of the liver and bone narrow, the activity of ALA synthetase (ALA-S) was markedly increased, and the activities of both uroporphyrinogen I synthetase (URO-S) and ferrochelatase were decreased. It was characteristic in this case that the enzymatic abnormalities found in both acute intermittent porphyria (AIP) and variegate porphyria (VP) coexisted.Biochemical analysis of the sciatic nerve showed an increase of ALA-S activity and a decrease of both URO-S and ALA dehydrase activities. This was the first report that indicated the presence of abnormal activities of the heme biosynthetic enzymes in the peripheral nerves of porphyric patients. The possibility was discussed that these enzymatic abnormalities of the heme biosynthesis in the peripheral nerve itself might be strongly related to the pathogenesis of the porphyric neuropathy.     

生物素葡聚糖胺观测周围神经局部轴突运输的实验研究

目的 研究神经示踪剂生物素葡聚糖胺（BDA）用于直观观察周围神经局部轴突运输的可行性。方法 （1）显露双侧兔坐骨神经，于实验侧及对照侧坐骨神经干注射不同浓度、不同剂量BDA，对照侧注射生理盐水，术后6、12、24、48h取样。于光镜及共聚焦显微镜下观察样本。（2）将兔左侧坐骨神经横断损伤并缝合，分别于术后1～6周于损伤近侧神经干注射10％BDA，12h后取标本观察。结果 10％BDA可清晰地在周围神经轴突内显像，操作简单，结果易于观察。同时，坐骨神经断伤术后3周时有明确的轴浆运输的恢复。结论 BDA神经干局部注射后能较清楚而直观地显示局部轴突运输的情况。     

三点悬吊与完全单孔腹腔镜胆囊切除43例临床分析

目的总结43例单孔腹腔镜胆囊切除的手术经验,探讨其学习曲线及实用性推广。方法回顾性分析2010年7月至2011年12月收治43例胆囊功能障碍、有症状胆囊结石或胆囊息肉患者,甄选行单孔腹腔镜胆囊切除术（试验组）,与同期行传统三孔腹腔镜胆囊切除术49例（对照组）比较,统计分析两种术式的手术时间、患者术后并发症发生率及总住院时间。结果试验组三点悬吊法完成15例,完全单孔法完成26例,2例中转传统三孔腹腔镜胆囊切除。试验组平均手术时间为（72.8±9）min,第1例患者手术时间为96 min,随着手术经验积累,从第10例开始,平均手术时间缩短至（62.5±5）min,与对照组平均手术时间（59.4±3）min相比,差异无统计学意义（t=4.04,P=0.16）。试验组平均住院时间（3±1.1）d,对照组为（4±0.87）d,两组比较差异无统计学意义（t=3.28,P=0.17）。术后随访2~12个月,试验组1例患者出现切口液化,对照组2例患者出现伤口感染。两组患者均无切口疝,胆道损伤等并发症。结论单孔腹腔镜胆囊切除安全可行,其平均手术和住院时间与传统腔镜胆囊切除相近,但切口少,术后切口疼痛轻,美容效果好。经过10例手术可完成单孔胆囊切除学习曲线。     

Somatofugal axonal atrophy precedes development of axonal degeneration in acrylamide neuropathy

Somatofugal axonal atrophy is part of the neuronal perikaryal response to axonal injury (axon reaction). Chronic administration of acrylamide (AC) produces proximal atrophy in virtually all sensory fibers in lumbar dorsal root ganglion (DRG) despite the presence of many intact axons in the distal portion of the sciatic nerve. This suggests that the development of axonal atrophy in AC-intoxicated animals is not solely due to a toxic chemical-induced axonal degeneration (axotomy). In this study, we asked whether axonal atrophy arises before onset of axonal degeneration. Rats were given a single intraperitoneal (i.p.) high dose of AC (75 mg/kg), which blocks retrograde axonal transport, followed by daily intraperitoneal injections (30 mg/kg, for 4 days). At 5 days, sensory fibers in the L4 and L5 DRG appeared smaller in caliber and less circular in shape compared to fibers from age-matched normal animals. Axonal diameters of sensory fibers in the L5 dorsal root were significantly (p<0.05) reduced at distances up to 2 mm from the DRG. Quantitative electron microscopy demonstrated that the reduction in caliber was due to a decreased neurofilament (NF) content. Axonal degeneration was not present in the distal portion of both centrally (dorsal root) and peripherally (sciatic nerve) projecting sensory fibers at this time, although primary afferent terminals in muscles of the hindfeet were packed with NFs. The somatofugal progression of the atrophy was evident following more prolonged exposures (10–28 days). It is suggested that AC produces somatofugal axonal atrophy by inhibiting the delivery of a retrogradely transported target-derived “trophic” signal to the neuronal perikaryon.     

Nogo-A蛋白在小鼠中枢神经系统中的表达及其意义

目的　确定髓鞘关联蛋白Nogo -A在小鼠中枢神经系统 (CNS)细胞水平的分布特点 ,探讨Nogo -A蛋白在脊髓损伤后在CNS神经纤维再生中的作用。　方法　用成年C57BL/ 6小鼠的大脑、脊髓、周围组织以及自由落体致伤的脊髓组织作为研究对象 ,采用免疫组织化学方法观察Nogo -A蛋白的表达特点 ;培养鸡胚E12DRG神经元 ,测定在Nogo -A作用下神经元的生长锥萎陷值。　结果　在小鼠CNS中 ,Nogo -A蛋白的表达主要位于少突胶质细胞及其胞突包绕轴突所形成的髓鞘中 ,在周围组织中无表达。脊髓损伤后 ,在损伤灶的周围Nogo -A的表达呈中度增强 ;Nogo -A组的神经元生长锥萎陷率达 70 % ,明显高于空白对照组和载体对照组 ,差异有显著性意义 (P <0 .0 5)。　结论　Nogo -A蛋白在小鼠CNS细胞水平的分布特点对于调控CNS神经纤维轴突的再生可能起重要作用     

Lid retraction or no lid retraction in optic neuropathy with proptosis

A 58-year-old woman had a history of treated hyperthyroidism and presented with unilateral proptosis and visual loss. The diagnostic evaluation and differential diagnosis were discussed and the treatment of dysthyroid optic neuropathy was outlined.