银杏外种皮多糖的单糖组成分析

采用PMP柱前衍生化HPLC对水解后银杏外种皮多糖中的单糖组分进行研究。采用Agilent HC-C₁₈色谱柱（4.6 mm×250 mm,5 μm）;流动相0.1 mol·L^-1磷酸盐缓冲液（pH 6.8）-乙腈（84：16）等度洗脱;柱温40 ℃,流速1 mL·min^-1,检测波长245 nm。从银杏外种皮多糖水解液中分析鉴定了6种单糖,分别为甘露糖、鼠李糖、半乳糖醛酸、葡萄糖、半乳糖、阿拉伯糖,其摩尔比为0.032：0.14：0.296：0.403：0.106：0.046。     

腓骨肌萎缩症基因重复异常的检测

目的应用分子生物学方法对腓骨肌萎缩症(CMT)患者进行外周髓鞘蛋白(PMP22)基因重复异常的检测。方法应用多聚酶链反应(PCR)加双酶切的方法,对临床上诊断为腓骨肌萎缩症14个家系的先证者和47例散发患者及20例正常人进行基因重复异常研究,根据有无1760bp大小的酶切片断来判断是否为PMP22基因重复异常。结果13个家系检测出PMP22基因重复异常,占所收集家系的92.86%;28例散发者检出PMP22基因重复异常,占散发病例59.57%。结论PCR-双酶切法检测CMT基因重复异常比较快速、简单、易操作,目前为CMT1A型基因诊断首选方法。     

6个腓骨肌萎缩症1A型家系临床分析

目的探讨腓骨肌萎缩症(Charcot-Marie-Tooth disease, CMT)1A型的临床表现、神经电生理和肌肉MRI特点。方法回顾性分析6个CMT1A型家系中6例先证者及2例家系成员的临床资料、神经电生理特点和下肢肌肉的MRI影像学特征。结果 6例CMT1A型先证者的首发症状以双下肢无力为主,主要临床特征为进行性加重的四肢远端肌无力和肌肉萎缩,伴或不伴深、浅感觉障碍,腱反射减弱或消失,足内翻及高弓足畸形。神经电生理示神经传导速度减慢,感觉神经、运动神经可同时受累,感觉神经病变重于运动神经,下肢重于上肢。下肢肌肉MRI示小腿伴或不伴大腿的多发肌群萎缩,脂肪沉积及脂肪间隙增多。结论 CMT1A型呈散发或常染色体显性遗传,有特征性电生理改变,周围神经传导速度和下肢肌肉MRI检查有助于发现早期及不典型CMT1A型。     

A prospective,split-face,double-blinded,randomized study of the efficacy and safety of a fractional 1064-nm Q-switched Nd:YAG laser for photoaging-associated mottled pigmentation in Asian skin

Background: Laser toning using low-fluence 1064-nm Q-switched neodymium-doped yttrium aluminum laser (QSNY) has gained popularity in the treatment of photoaging-associated mottled pigmentation (PMP). However, hypopigmentation or lack of efficacy has been reported depending on the fluences used. Objective: To compare a novel fractional 1064-nm QSNY with conventional 1064-nm QSNY for the treatment of photoaging-associated mottled pigmentary lesions except epidermal lesions of lentigines and freckles through a randomized, split-face, double-blind study. Materials and methods: Thirteen Asian women were treated every week for 6 weeks with fractional 1064-nm QSNY on one side of the face and conventional 1064-nm QSNY on the other side. We evaluated the pigmentation area and severity index (PSI), melanin index, erythema index, and the patient's global assessment of improvement. Results: At three months post-treatment, the PSI score improved compared with baseline, by 14.48% on the conventional 1064-nm QSNY side and 21.81% on the fractional 1064-nm QSNY side. Both groups showed improvements in the melanin index. Conclusion: Both fractional 1064-nm QSNY and strictly low-fluence conventional 1064-nm QSNY are moderately effective against PMP and other photoaging signs. Fractional laser toning shows better subjective outcomes than conventional toning.     

Determination of genomic copy number with quantitative microsphere hybridization

We developed a novel quantitative microsphere suspension hybridization (QMH) assay for determination of genomic copy number by flow cytometry. Single copy (sc) products ranging in length from 62 to 2,304 nucleotides [Rogan et al., 2001; Knoll and Rogan, 2004] from ABL1 (chromosome 9q34), TEKT3 (17p12), PMP22 (17p12), and HOXB1 (17q21) were conjugated to spectrally distinct polystyrene microspheres. These conjugated probes were used in multiplex hybridization to detect homologous target sequences in biotinylated genomic DNA extracted from fixed cell pellets obtained for cytogenetic studies. Hybridized targets were bound to phycoerythrin-labeled streptavidin; then the spectral emissions of both target and conjugated microsphere were codetected by flow cytometry. Prior amplification of locus-specific target DNA was not required because sc probes provide adequate specificity and sensitivity for accurate copy number determination. Copy number differences were distinguishable by comparing the mean fluorescence intensities (MFI) of test probes with a biallelic reference probe in genomic DNA of patient samples and abnormal cell lines. Concerted 5' ABL1 deletions in patient samples with a chromosome 9;22 translocation and chronic myelogenous leukemia were confirmed by comparison of the mean fluorescence intensities of ABL1 test probes with a HOXB1 reference probe. The relative intensities of the ABL1 probes were reduced to 0.59+/-0.02 fold in three different deletion patients and increased 1.42+/-0.01 fold in three trisomic 9 cell lines. TEKT3 and PMP22 probes detected proportionate copy number increases in five patients with Charcot-Marie-Tooth Type 1a disease and chromosome 17p12 duplications. Thus, the assay is capable of distinguishing one allele and three alleles from a biallelic reference sequence, regardless of chromosomal context.     

Axonal damage and demyelination in long-term dorsal root ganglia cultures from a rat model of Charcot-Marie-Tooth type 1A disease

Clinical progression in hereditary and acquired demyelinating disorders of both the central and peripheral nervous system is mainly due to a time-dependent axonal impairment. We established 90-day dorsal root ganglia (DRG) cultures from a rat model of Charcot-Marie-Tooth type 1A (CMT1A) neuropathy to evaluate the structure of myelin and axons, and the expression of myelin-related proteins and cytoskeletal components, by morphological and molecular techniques. Both wild-type and CMT1A cultures were rich in myelinated fibres. Affected cultures showed dysmyelinated internodes and focal myelin swellings. Furthermore, uncompacted myelin and smaller axons with increased neurofilament (NF) density were found by electron microscopy, and Western blots showed higher levels of nonphosphorylated NF. Confocal microscopy demonstrated an abnormal distribution of the myelin-associated glycoprotein which, instead of being expressed at the noncompact myelin level, showed focal accumulation along the internodes while other myelin proteins were normally distributed. These findings suggest that CMT1A DRG cultures, similarly to the animal model and human disease, undergo axonal atrophy over a period of time. This model may be utilized to study the molecular changes underlying demyelination and secondary axonal impairment. As axonal damage may occur after just 3 months and tissue cultures represent a strictly controlled environment, this model may be ideal for testing neuroprotective therapies.     

Nerve ultrasound findings differentiate Charcot-Marie-Tooth disease (CMT) 1A from other demyelinating CMTs

Objective

Ulnar/median motor nerve conduction velocity (MNCV) is ≤38?m/s in demyelinating Charcot-Marie-Tooth disease (CMT). Previous nerve high resolution ultrasound (HRUS) studies explored demyelinating CMT assuming it as a homogeneous genetic/pathological entity or focused on CMT1A.

Vitamin B-6 metabolism in the brains of young adult and senescent mice

The steady state levels of pyridoxal-P and pyridoxamine-P, the activities of pyridoxal (pyridoxine) kinase and pyridoxamine-(pyridoxine)-P oxidase, and the metabolism of [³H]pyridoxine were determined in the brains of C57B1/6J mice of selected ages. The steady state concentratioons of the coenzymes and the activities of the enzymes required for pyridoxal-P synthesis did not change significantly as a function of age. The uptake and metabolism of vitamin B-6 by the brain was studied by injecting [³H]pyridoxine in the tail vein of young adult and senescent mice, killing the mice after 15 or 30 min, and separating the B-6 metabolites by ion exchange chromatography. More total radioactivity was accumulated in 15 min in the brains of the senescent mice than the brains of the young mice. The brains from both age groups rapidly synthesized pyridoxal-P from pyridoxine. However, less radioactive pyridoxamine-P and more radioactive pyridoxal were formed in the brains of the senescent mice than in the young mice killed 15 min after injection. These results are similar to those obtained for the metabolim of [³H]-pyridoxine in the liver of these senescent mice. The senescent mice appear to be vitamin B-6 deficient, have decreased brain amino acid transaminase activity, and either increased pyridoxal-P phosphatase activity or decreased protection of brain pyridoxal-P.     

A novel<Emphasis Type="Italic"> PMP22</Emphasis> mutation Ser22Phe in a family with hereditary neuropathy with liability to pressure palsies and CMT1A phenotypes

We describe a Cypriot family in which some family members presented with episodes of pressure palsies, while other family members had a slowly progressive chronic polyneuropathy typical of the Charcot-Marie-Tooth type 1 phenotype. All family members were evaluated clinically, with nerve conduction studies, and with genetic testing. In all affected individuals there was clinical and electrophysiological evidence of diffuse demyelinating sensorimotor polyneuropathy and a novel point mutation in the PMP22 gene (Ser22Phe) was identified.     

Behavioural profiling of a murine Charcot-Marie-Tooth disease type 1A model

Different features of motor behaviour were studied on a transgenic mouse model of Charcot-Marie-Tooth's disease (CMT). Mutants with 4 or 7 copies of the human PMP22 gene leading to a phenotype significantly close to CMT's disease type 1A were compared with control animals. The aim of the study was to validate this transgenic model and to characterise the impairments occurring in the various lines. Three main types of analysis were performed in 2-month-old mice without any peculiar visible deficit: (i) a study of standardised clinical tests (SHIRPA protocol) demonstrated that only a few motor deficits were expressed; (ii) a measurement of general spontaneous activity by means of a commercial video-tracking system was performed and revealed that the main spontaneous activities were identical in the three lines with, however, some slight localised modifications; and, (iii) by contrast, the three lines respond very differently to the footprints, grip strength, splay test and rotarod test. Even in lines with a significantly limited copy number of the transgene, we observed and quantified impairments. In conclusion, mutants of CMT1A seem to be a very pertinent model of this human pathology and will certainly be useful for therapeutic procedures and for theoretical studies on this disease.