The Cerebral Palsy Advice Clinic

OBJECTIVE: To investigate the characteristics of gene structure in facioscapulohumeral muscular dystrophy (FSHD)-related 4q35 subtelomere, to analyze the distribution of 2 alleles (4qA and 4qB) distal to D4Z4 of this locus, and to further elucidate the genotype-phenotype correlation in Chinese Han FSHD patients. METHODS: Peripheral blood samples were collected from 52 unrelated families including 62 FSHD-affected and 57 unaffected members. Genomic DNA was extracted from the lymphocytes according to the specific procedure designed to minimize DNA shearing, then digested with EcoRI or HindIII, or double digested with EcoRI and BlnI. The cleaved DNA was separated by pulsed field electrophoresis (PFGE) and Southern blotting with the probes p13E-11, 4qA, and 4qB. The size of FSHD-causing 4qA allele and its distribution was analyzed by “curve fitting”. Then the characteristics of translocation and mosaicism, the frequencies of two allelic variants of chromosome 4q and their genotypes were calculated to analyze the genotype-phenotype correlation. RESULTS: It was found that 69 patients carried a short chromosome 4-type allele of 4qA origin with the length 10 - 38 kb. The mean length of these pathogenic EcoRI/4qA arrays was 20 kb +/- 7 kb, without significant difference between the sporadic cases and familial cases (t = 1.413, P > 0.05). Three different translocation types were observed with a translocation rate of 14.49%. The rate of 4q–>10q translocation was 13.04%, significantly higher than that of 10q–>4q translocation (1.45%, chi(2) = 6.900, P < 0.05). Somatic mosaicism was detected in a male sporadic case and a female asymptomatic familial case. In 57 cases with standard configuration distribution, the frequency of 4qA/4qB heterozygote was 61.40%, significantly higher than that of 4qA/4qA homozygote (38.60%, (chi(2) = 5.930, P < 0.05). There were not significant differences in the repeat size distributions and assessment of clinical severity between the sporadic and familial cases (t = -0.039, P > 0.05; H = 0.693, P > 0.05). CONCLUSION: About 95% of Chinese FSHD patients carry a pathogenic 4-type allele of 4qA origin less than 30 kb long. The frequent translocations between chromosome 4q and 10q may play an essential role for FSHD mechanism. The frequency of 4qA/4qB heterozygote is significantly higher than that of 4qA/4qA homozygote, while the allelic variant genotypes do not contribute to modify FSHD manifestations.

OBJECTIVE: To describe the course, complications, and prognosis of Ullrich congenital muscular dystrophy (UCMD), with special reference to life-changing events, including loss of ambulation, respiratory insufficiency, and death. METHODS: Review of the case notes of 13 patients with UCMD, aged 15 years or older at last visit, followed up at a tertiary neuromuscular centre, London, UK, from 1977 to 2007. Data collected were age at onset of symptoms, presenting symptoms, mobility, contractures, scoliosis, skin abnormalities, respiratory function, and feeding difficulties. RESULTS: The mean age at onset of symptoms was 12 months (SD 14 months). Eight patients (61.5%) acquired independent ambulation at a mean age of 1.7 years (SD 0.8 years). Nine patients (69.2%) became constant wheelchair users at a mean age of 11.1 years (SD 4.8 years). Three patients continued to ambulate indoors with assistance. Forced vital capacity (FVC) values were abnormal in all patients from age 6 years. The mean FVC (% predicted) declined at a mean rate of 2.6% (SD 4.1%) yearly. Nine patients (69.2%) started noninvasive ventilation at a mean age of 14.3 years (SD 5.0 years). Two patients died of respiratory insufficiency. CONCLUSION: In Ullrich congenital muscular dystrophy (UCMD), the decline in motor and respiratory functions is more rapid in the first decade of life. The deterioration is invariable, but not always correlated with age or severity at presentation. This information should be of help to better anticipate the difficulties encountered by patients with UCMD and in planning future therapeutic trials in this condition.

Muscular dystrophy (MD) comprises a group of diseases characterized by progressive muscle weakness that induces functional deterioration. Clinical management requires the use of a well-designed scale to measure patients’ functional status. This study aimed to investigate the quality of the functional scales used to assess patients with different types of MD. The Brooke scale and the Vignos scale were used to grade arm and leg function, respectively. The Barthel Index was used to evaluate the function of daily living activity. We performed tests to assess the acceptability of these scales. The characteristics of the different types of MD are discussed. This was a multicenter study and included patients diagnosed with Duchenne muscular dystrophy (DMD) (classified as severely progressive MD), Becker muscular dystrophy (BMD), limb girdle muscular dystrophy (LGMD) and facioscapulohumeral muscular dystrophy (FSHD). BMD, LGMD, and FSHD were classified as slowly progressive MD. The results demonstrated that the Brooke scale was acceptable for grading arm function in DMD, but was unable to discriminate between differing levels of severity in slowly progressive MD. The floor effect was large for all types of slowly progressive MD (range, 20.0-61.9), and was especially high for BMD. The floor effect was also large for BMD (23.8%) and FSHD (50.0%) using the Vignos scale. Grades 6-8 of the Vignos scale were inapplicable because they included items involving the use of long leg braces for walking or standing, and some patients did not use long leg braces. In the Barthel Index, a ceiling effect was prominent for slowly progressive MD (58.9%), while a floor effect existed for DMD (17.9%). Among the slowly progressive MDs, FSHD patients had the best level of functioning; they had better leg function and their daily living activities were less affected than patients with other forms of slowly progressive MD. The results of this study demonstrate the acceptability of the different applications used for measuring functional status in patients with different types of MD. Some of the limitations of these measures as applied to MD should be carefully considered, especially in patients with slowly progressive MD. We suggest that these applications be used in combination with other measures, or that a complicated instrument capable of evaluating the various levels of functional status be used.

High levels of labile zinc accumulate in degenerating neurons after brain injury, such as ischemic stroke, trauma, epilepsy, and hypoglycemia. Cytosolic zinc accumulation is also found in brain neurons undergoing apoptosis during development or after neuronal target ablation. Thus, staining with zinc-specific probes can be used to identify neuronal death in the brain. In this study, mice were intraperitoneally given four 20 mg/kg doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) at 2-hour intervals, and dopaminergic neurons were then evaluated for zinc accumulation and apoptosis. In the substantia nigra pars compacta, zinc-specific fluorescent dyes revealed that all degenerating neurons, identified by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL), or acid fuchsin or Fluoro-Jade C staining, contained high levels of cytosolic labile zinc. Nuclear condensation/fragmentation was noted in dopaminergic neurons with cytosolic zinc accumulation, indicating apoptotic cell death. These findings support the supposition that cytosolic labile zinc accumulation is an indicator of degenerating dopaminergic neurons in animal models of Parkinson’s disease.

Long term subthalamic nucleus (STN) high frequency stimulation (HFS) can improve most symptoms of Parkinson’s disease(PD) patients and decrease the dosage of antiparkinsonian drug such as Madopar. The mechanism of STN HFS for PD still remains elusive. We hypothesize that the level of dopamine (DA) and its metabolites in the corpus striatum is increased after long term STN HFS. The aim of this study was to examine the DA and its metabolites in the extracellular space of corpus striatum in hemiparkinson monkeys during long term STN HFS. Four rhesus monkeys were induced to hemiparkinsonian models by injecting 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) through right internal carotid artery. Then two of them were underwent long term right STN HFS for the subsequent microdialysis sessions. Four microdialysis probe cannulas were implanted into bilateral putamen and caudate nucleus respectively. The microdialysis probe was put into the microdialysis probe cannula of bilateral putamen and caudate nucleus. Dialysates of extracellular space in corpus striatum were collected prior to STN HFS, and subsequently 8 hour, 1 week, 1 month, 2 month, 8 month and 10 month after STN HFS. The level of DA and its metabolites were determined by high performance liquid chromatography and subthalamic nucleus electrochemical detection ( HPLC-ECD). HFS significantly improved PD symptoms of the monkeys. Rotation evoked by apomorphine (APO) disappeared immediately after HFS pulse generator turned on. The levels of DA and its metabolites in putamen and caudate nucleus of electrode side increased significantly at different time points after stimulation. Long term STN HFS significantly improved symptoms of hemiparkinsonian rhesus monkey, which might be due to the increase of dopamine and /or its metabolites in corpus striatum.

Background and purpose: Dopamine inhibits renal cell Na(+),K(+)-ATPase activity and cell sodium transport by promoting the internalization of active molecules from the plasma membrane, whereas angiotensin II (ATII) stimulates its activity by recruiting new molecules to the plasma membrane. They achieve such effects by activating multiple and distinct signalling molecules in a hierarchical manner. The purpose of this study was to investigate whether dopamine and ATII utilize scaffold organizer proteins as components of their signalling networks, in order to avoid deleterious cross talk. Experimental approach: Attention was focused on a multiple PDZ domain protein, Pals-associated tight junction protein (PATJ). Ectopic expression of PATJ in renal epithelial cells in culture was used to study its interaction with components of the dopamine signalling cascade. Similarly, expression of PATJ deletion mutants was employed to analyse its functional relevance during dopamine-, ATII- and insulin-dependent regulation of Na(+),K(+)-ATPase. Key results: Dopamine receptors and components of its signalling cascade mediating inhibition of Na(+),K(+)-ATPase interact with PATJ. Inhibition of Na(+),K(+)-ATPase by dopamine was prevented by expression of mutants of PATJ lacking PDZ domains 2, 4 or 5; whereas the stimulatory effect of ATII and insulin on Na(+),K(+)-ATPase was blocked by expression of PATJ lacking PDZ domains 1, 4 or 5. Conclusions and implications: A multiple PDZ domain protein may add functionality to G protein-coupled and tyrosine kinase receptors signalling during regulation of Na(+),K(+)-ATPase. Signalling molecules and effectors can be integrated into a functional network by the scaffold organizer protein PATJ via its multiple PDZ domains.

Exposure to cocaine causes many neuroadaptations including alterations in several neurotransmitter receptors and transporters. This study investigated potential mechanisms of cocaine-induced receptor and transporter regulation by measuring levels of two proteins involved in receptor and transporter trafficking, dynamin 2 and G protein-coupled receptor kinase 2 (GRK2). Male Fischer rats received three daily injections of cocaine, 15 mg/kg, in a binge-pattern (at 1 h intervals) for 1, 3, or 14 days. Brain regions of interest were collected 30 min after the last injection and proteins measured by Western blot. Acute binge-pattern cocaine administration produced a significant increase in both dynamin 2- and GRK2-immunoreactivity (227% and 358% of control) in the nucleus accumbens and GKR2 (150% of control) in the caudate putamen. Tolerance to this effect occurred, as levels of both proteins returned to baseline after 3 days of cocaine. In contrast, dynamin 2 and GRK2 were significantly decreased in the nucleus accumbens after chronic cocaine. This pattern of regulation was unique to the nucleus accumbens and not seen in the frontal cortex or substantia nigra. Pretreatment with either the dopamine (DA) D1 receptor antagonist SCH 23390 or D2 receptor antagonist eticlopride prior to acute cocaine blocked the upregulation of dynamin 2 and GRK2 in the nucleus accumbens. However, only eticlopride was effective in attenuating the decrease in these proteins following chronic cocaine exposure. These results demonstrate that two proteins involved in receptor and transporter trafficking are selectively regulated in the nucleus accumbens following acute versus chronic cocaine exposure, and dopamine receptor activation is required for this regulation. Synapse 63:863-870, 2009. (c) 2009 Wiley-Liss, Inc.

It is well documented that neonatal neurosteroid administration influences brain development. In our previous studies, administration of pregnenolone, the precursor of neurosteroids, during the neonatal period altered the activity of dopamine (DA) in the striatum. Furthermore, neonatal treatment with pregnenolone or dehydroepiandrosterone (DHEA) increased synapse-related protein synapsin I as well as neuropeptide Y (NPY) in the hippocampus. The present study examined the effects of neonatal treatment with pregnenolone or DHEA on synapsin I, DA transporter (DAT), dynorphin A, and NPY in the striatum and the core and shell of the nucleus accumbens at post-puberty. Administration of pregnenolone or DHEA during the neonatal period increased immunodensity of synapsin I in the dorsomedial or ventrolateral striatum. DAT immunodensity in the striatum and the nucleus accumbens core as well as dynorphin A immunodensity in the nucleus accumbens core were increased in DHEA-treated but not in pregnenolone-treated rats. In addition, the size, but not numbers, of NPY-positive cells in the nucleus accumbens core was increased in pregnenolone- and DHEA-treated rats. The results suggest that neurosteroid levels during the neonatal period have larger impact on synaptic formation, development of DA and NPY systems in the nigrostriatal rather than the mesolimbic pathway.

PURPOSE: To determine the values of iron accumulation in the basal ganglia of healthy volunteers of different ages with R2* and raw signal intensity measurements from T1-weighted magnetic resonance (MR) images, supported by voxel-based relaxometry (VBR), and to compare them with previously reported iron concentrations found in autopsy material. MATERIALS AND METHODS: The ethics committee approved the study, and the participants or their parents gave written informed consent. Eighty subjects (41 female and 39 male subjects; age range, 1-80 years) were examined at 1.5 T. For each subject, R2* values were calculated. Curves for R2* versus age were obtained for globus pallidus (GP), putamen, caudate nucleus, substantia nigra (SN), and frontal white matter (FWM). To highlight possible differences in iron concentration among the age decades, VBR was applied. Signal intensity values were estimated on T1-weighted fast low-angle shot images, and regions of interest were drawn in each nucleus. R2* values were also compared with iron concentrations reported in a postmortem study. Statistical analysis was performed (t test), and a difference with P < .05 (FDR corrected) was significant. RESULTS: The curves for R2* versus age showed an exponential increase with increasing age in all the basal ganglia. VBR demonstrated significant differences (P < .05, corrected) in the comparison between the 2nd and the following decades for lenticular nuclei. Good correlation coefficients were found for GP (R(2) = 0.64), putamen (R(2) = 0.51), and SN (R(2) = 0.53) when compared with findings in the postmortem study. Signal intensity curves were similar to the R2* curves. CONCLUSION: R2* measurements can be used to quantify brain iron accumulation and thus may allow better evaluation of neurodegenerative diseases associated with iron deposition. (c) RSNA, 2009.

Local field potential (LFP) oscillations in the brain reflect organization thought to be important for perception, attention, movement, and memory. In the basal ganglia, including dorsal striatum, dysfunctional LFP states are associated with Parkinson’s disease, while in healthy subjects, dorsal striatal LFPs have been linked to decision-making processes. However, LFPs in ventral striatum have been less studied. We report that in rats running a spatial decision task, prominent gamma-50 (45-55 Hz) and gamma-80 (70-85 Hz) oscillations in ventral striatum had distinct relationships to behavior, task events, and spiking activity. Gamma-50 power increased sharply following reward delivery and before movement initiation, while in contrast, gamma-80 power ramped up gradually to reward locations. Gamma-50 power was low and contained little structure during early learning, but rapidly developed a stable pattern, while gamma-80 power was initially high before returning to a stable level within a similar timeframe. Putative fast-spiking interneurons (FSIs) showed phase, firing rate, and coherence relationships with gamma-50 and gamma-80, indicating that the observed LFP patterns are locally relevant. Furthermore, in a number of FSIs such relationships were specific to gamma-50 or gamma-80, suggesting that partially distinct FSI populations mediate the effects of gamma-50 and gamma-80.