The role of gangliosides in the organisation of the node of Ranvier examined in glycosyltransferase transgenic mice

Gangliosides are a family of sialic acid containing glycosphingolipids highly enriched in plasma membranes of the vertebrate nervous system. They are functionally diverse in modulating nervous system integrity, notably at the node of Ranvier, and also act as receptors for many ligands including toxins and autoantibodies. They are synthesised in a stepwise manner by groups of glycosyl‐ and sialyltransferases in a developmentally and tissue regulated manner. In this review, we summarise and discuss data derived from transgenic mice with different transferase deficiencies that have been used to determine the role of glycolipids in the organisation of the node of Ranvier. Understanding their role at this specialised functional site is crucial to determining differential pathophysiology following directed genetic or autoimmune injury to peripheral nerve nodal or paranodal domains, and revealing the downstream consequences of axo‐glial disruption.     

Randomized controlled trial of brain-derived neurotrophic factor in Guillain-Barré syndrome: a pilot study.

Brain-derived neurotrophic factor (BDNF) has the theoretical potential to protect neurones from axonal degeneration. The objective of this study was to discover whether brain-derived neurotrophic factor is safe in Guillain-Barré syndrome, and to make preliminary observations of its efficacy. This was a parallel group randomized controlled trial of subcutaneous brain-derived neurotrophic factor 25 microg/kg daily compared with placebo for up to 24 weeks or until patients could walk without aid. Six patients received brain-derived neurotrophic factor, of whom three had serious adverse events including one death. Four patients received placebo, of whom two had serious adverse events including one death. The rate and extent of recovery were similar in the two groups. This pilot study did not detect any serious adverse events attributed to brain-derived neurotrophic factor treatment.     

Nerve root hypertrophy in chronic inflammatory demyelinating polyneuropathy

A patient with chronic inflammatory demyelinating polyneuropathy (ClDP) and centrel demyelinating disease is desoribed in whom striking nodular filling defects on multiple lumbar–sacral nerve roots, mimicking neurofibromata, were observed at myelography and magnetic resonance imaging. We suggest that these lesions are secondary to recurrent segmental demyelination and remyelination and that the differential diagnosis of this radiological feature should include CIDP. © 1994 John Wiley & Sons, Inc.     

单鼻孔直入经筛骨垂直板后段经蝶入路切除垂体腺瘤

目的 介绍、推广单鼻孔直入经筛骨垂直板后段经蝶入路切除垂体腺瘤的手术经验，探讨该术式的优越性。方法 2001年10月以来对43例垂体腺瘤采用单鼻孔直入经筛骨垂直板后段经蝶入路手术。结果 本组无手术死亡，平均住院时间1周。随访3～25个月。MR复查示肿瘤全切除32例，近全切除9例，大部分切除2例。有内分泌症状的37例中．10例恢复正常，15例改善，12例同术前。结论 单鼻孔直入经筛骨垂直板后段经蝶手术最大限度地利用了鼻腔的自然间隙，入路直接．手术时间短．创伤轻微．并发症较少．是目前最为理想的经蝶手术术式．     

Millipore analysis of valvular fluid in sterile valve malfunctions

Malfunctions of sterile shunts may result from valvular dysfunction. The cerebrospinal fluid shunt valves of 14 patients were excised during surgery for sterile shunt malfunctions. In 6 patients, the malfunction was due specifically to a valve malfunction. Cerebrospinal fluid from each valve was passed through a millipore filter, which was then stained using either hematoxylin and eosin or periodic acid-Schiff. The stained millipore filters were examined by a neuropathologist who was unaware of the cause of the shunt malfunction. Although inflammatory cells were detected in all cases, the patients with valve malfunctions were found to have numerous macrophages and giant multinucleated reactive cells within their valves, while cerebrospinal fluid from valves that had been removed during shunt revisions for reasons other than a malfunctioning valve contained only rare mononuclear cells or macrophages. No valve contained erythrocytes, fibrinous matter, neural or glial tissue, or choroid plexus. The possible causes of valve malfunction, including infection and allergic reactions, are discussed. All patients did well after simple replacement of the valve.     

Call for membership committee members

OBJECTIVE: Growing evidence indicates that life-sustaining therapies for the treatment of acute myocardial infarction (AMI) are underused among patients eligible for therapy, including the elderly and women. We examined the effect of a patient's comorbidity burden on use of these highly effective therapies in eligible populations of individuals with AMI. DESIGN: Retrospective cohort design. SETTING AND PATIENTS: We reviewed the medical records of 2,409 individuals at 37 Minnesota hospitals from October 1992 through July 1993 with an admission diagnosis of AMI, suspected AMI, or rule-out AMI, who met electrocardiographic, laboratory, and clinical criteria for AMI. MEASUREMENTS AND MAIN RESULTS: Using multivariate logistic regression models, we determined the association between a validated comorbidity measure and the proportion of eligible patients who received thrombolysis or aspirin. Controlling for other factors previously reported to influence rates of study treatment, the odds of receipt of thrombolysis among patients with severe comorbidity was 0.49 (95% confidence interval [CI] 0.27, 0.88) when compared with individuals without such limitation. Similarly, the odds of aspirin treatment among study patients with severe comorbidity was 0.46 (95% CI 0.30, 0.72), compared with individuals without severe comorbidity. We did not distinguish any differences in patterns of treatment with either study treatment among patients with mild or moderate comorbidity when compared with individuals without any concomitant comorbidity. CONCLUSIONS: This study indicates that patients with severe mental and physical comorbidities are less likely to receive standard therapies for AMI recommended in national treatment guidelines.