Resequencing of four novel alleles with nanopore technology.

Long nanopore reads allow phasing of heterozygous positions but show limitations in sequencing of homopolymers.

Intracranial EEG analysis in tumor-related epilepsy: Evidence of distant epileptic abnormalities.

OBJECTIVE: In patients with tumor-related epilepsy (TRE), surgery traditionally focuses on tumor resection; but identification and removal of associated epileptogenic zone may improve seizure outcome. Here, we study spatial relationship of tumor and seizure onset and early spread zone (SOSz). We also perform quantitative analysis of interictal epileptiform activities in patients with both TRE and non-lesional epilepsy in order to better understand the electrophysiological basis of epileptogenesis. METHODS: Twenty-five patients (11 with TRE and 14 with non-lesional epilepsy) underwent staged surgery using intracranial electrodes. Tumors were outlined on MRI and images were coregistered with post-implantation CT images. For each electrode, distance to the nearest tumor margin was measured. Electrodes were categorized based on distance from tumor and involvement in seizure. Quantitative EEG analysis studying frequency, amplitude, power, duration and slope of interictal spikes was performed. RESULTS: At least part of the SOSz was located beyond 1.5 cm from the tumor margin in 10/11 patients. Interictally, spike frequency and power were higher in the SOSz and spikes near tumor were smaller and less sharp. Interestingly, peritumoral electrodes had the highest spike frequencies and sharpest spikes, indicating greatest degree of epileptic synchrony. A complete resection of the SOSz resulted in excellent seizure outcome. CONCLUSIONS: Seizure onset and early spread often involves brain areas distant from the tumor. SIGNIFICANCE: Utilization of epilepsy surgery approach for TRE may provide better seizure outcome and study of the intracranial EEG may provide insight into pathophysiology of TRE.

CMT1X phenotypes represent loss of GJB1 gene function.

OBJECTIVE: To investigate possible genotype-phenotype correlations and to evaluate the natural history of patients with Charcot-Marie-Tooth disease type 1X (CMT1X). BACKGROUND: CMT1X is caused by over 260 distinct mutations in the gap junction beta 1 (GJB1) gene, located on the X chromosome, which encodes the gap junction protein connexin 32 (Cx32). The natural history of CMT1X is poorly understood, and it remains unknown whether particular mutations cause more severe neuropathies through abnormal gain-of-function mechanisms. METHODS: We evaluated 73 male patients with CMT1X, who each have 1 of 28 different GJB1 mutations predicted to affect nearly all domains of Cx32. Disability was evaluated quantitatively by the CMT Neuropathy Score (CMTNS) as well as by the CMT Symptom Score (CMTSS) and the CMT Examination Score (CMTES), which are both based on the CMTNS. Patients were also evaluated by neurophysiology. RESULTS: In all patients, disability increased with age, and the degree of disability was comparable with that observed in patients with a documented GJB1 deletion. Disability correlated with a loss of motor units as assessed by motor unit number estimates. CONCLUSIONS: Taken together, these data suggest that most GJB1 mutations cause neuropathy by a loss of normal connexin 32 function. Therefore, treatment of male patients with Charcot-Marie-Tooth disease type 1X may prove amenable to gene replacement strategies.

Reliability and validity of the CMT neuropathy score as a measure of disability.

OBJECTIVE: To determine the validity and reliability of the Charcot-Marie-Tooth disease (CMT) neuropathy score (CMTNS) in patients with inherited neuropathy. BACKGROUND: Natural history studies and potential treatment trials for patients with various forms of CMT are limited by the lack of quantitative methodologies to monitor disease progression. Most cases of CMT can be considered length-dependent axonal neuropathies because disability for even the demyelinating forms correlates with length-dependent axonal degeneration. The total neuropathy score (TNS) is a validated composite measure of disability in length-dependent axonal neuropathies but is weighted toward predominantly sensory neuropathies. Thus, the authors have devised a CMTNS, modified from the TNS, to provide a single measure to quantify CMT disability. METHODS: The authors measured inter- and intrainvestigator reliability of the CMTNS and performed a validation of the score with the Neuropathy Impairment Score (NIS), patient self-assessment scores, an ambulation index, and other measures of disability. RESULTS: Inter- and intrainvestigator reliability was more than 95% in the 60 patients evaluated. Patients could be divided into mild (CMTNS, < or =10), moderate (CMTNS, 11 to 20), and severe (CMTNS, > or =21) categories and demonstrated excellent correlations among all measures of disability. CONCLUSION: The Charcot-Marie-Tooth disease (CMT) neuropathy score is a validated measure of length-dependent axonal and demyelinating CMT disability and can be investigated as an end point for longitudinal studies and clinical trials of CMT.

Volumetric MRI, pathological, and neuropsychological progression in hippocampal sclerosis.

OBJECTIVE: To examine the relationships between age at onset and duration of seizure disorder with severity of hippocampal sclerosis (HS) and cognitive functioning in patients with HS and unilateral temporal lobe epilepsy. METHODS: Twenty-six subjects had left temporal lobe seizure onset; 20 had right temporal onset. Measures were age at seizure onset, duration of seizure disorder divided by age (seizure duration), history of febrile convulsion (FC), ratio of the smaller hippocampal volume to the larger (HF) as determined by volumetric MRI, and pathologic HS grade. RESULTS: Results showed that pathologic HS grade and HF were positively related to seizure duration, and negatively related to seizure onset. When subjects were divided into onset prior to age 10 versus later, subjects with earlier onset had higher mean pathologic HS grade and smaller (more asymmetric) mean HF. When subjects were divided into seizure duration <0.5 (i.e., less than half current lifetime) vs greater, subjects with seizure duration > or =0.5 had higher mean pathologic HS grade and lower mean HF. There was also evidence for earlier age at seizure onset and longer seizure duration being associated with worse performance on neuropsychological measures. FC was not related to either seizure duration or age at seizure onset, but patients with a history of FC showed higher pathologic HS grade and lower HF. A history of FC was not related to cognitive functioning. CONCLUSIONS: Unilateral HS patients with earlier seizure onset and longer duration of epilepsy have more severe HS and greater hippocampal volume asymmetry. This suggests that HS may be a progressive disorder with risk for cognitive dysfunction.

Peripheral WBC count and serum prolactin level in various seizure types and nonepileptic events.

PURPOSE: To analyze effects of different types of seizures and nonepileptic events as well as effects of seizure duration and lapse between the time of seizure and blood collection on serum prolactin level and peripheral white blood cell (WBC) count. METHODS: We prospectively collected blood samples from all patients admitted to our Epilepsy Monitoring Unit at baseline and after an event. Blood samples were analyzed, and serum prolactin level and WBC count were determined. Statistical analyses were performed to evaluate the relation of each type of seizure, its duration, and time lapse between a seizure and collection of blood sample to the serum prolactin level and peripheral WBC count. RESULTS: Serum prolactin level increases above twice the level at baseline after a complex partial seizure or a generalized seizure. Peripheral WBC count is elevated above the upper limit of normal in about one third of cases after a generalized seizure. In generalized seizures, the length of a seizure is positively associated, whereas the lapse time between the seizure onset and blood draw is negatively correlated with the increase in WBC count. Thus the longer the seizure and quicker the blood draw, the higher the WBC count. CONCLUSIONS: We conclude that complex partial or generalized seizures are associated with an increase in serum prolactin level. Peripheral WBC count increases significantly after a generalized seizure and is probably transient in nature.

Synthesis of C(3) benzofuran-derived bisaryl quaternary centers: approaches to diazonamide A.

[reaction: see text] Two complementary strategies for the synthesis of the diazonamide A bisaryl quaternary center are described. The first strategy relies upon an extremely facile tandem cyclopropanation/ring-opening sequence, which has proven amenable to chiral catalysis to provide enantioenriched material. The second strategy relies upon a more concise alkylation route ideal for material advancement.

Neurological dysfunction and axonal degeneration in Charcot-Marie-Tooth disease type 1A.

Charcot-Marie-Tooth disease type 1A (CMT1A), the most frequent form of CMT, is caused by a 1.5 Mb duplication on the short arm of chromosome 17. Patients with CMT1A typically have slowed nerve conduction velocities (NCVs), reduced compound motor and sensory nerve action potentials (CMAPs and SNAPs), distal weakness, sensory loss and decreased reflexes. In order to understand further the molecular pathogenesis of CMT1A, as well as to determine which features correlate with neurological dysfunction and might thus be amenable to treatment, we evaluated the clinical and electrophysiological phenotype in 42 patients with CMT1A. In these patients, muscle weakness, CMAP amplitudes and motor unit number estimates correlated with clinical disability, while motor NCV did not. In addition, loss of joint position sense and reduction in SNAP amplitudes also correlated with clinical disability, while sensory NCV did not. Taken together, these data strongly support the hypothesis that neurological dysfunction and clinical disability in CMT1A are caused by loss or damage to large calibre motor and sensory axons. Therapeutic approaches to ameliorate disability in CMT1A, as in amyotrophic lateral sclerosis and other neurodegenerative diseases, should thus be directed towards preventing axonal degeneration and/or promoting axonal regeneration.

Explicit memory in pregnant women.

OBJECTIVE: The study was conducted to systematically investigate previous anecdotal reports of memory decline during pregnancy. STUDY DESIGN: We used a longitudinal design to investigate memory in women throughout pregnancy and in the postpartum period. Closely matched, nonpregnant women were similarly studied at equivalent intervals. We also assessed degree of depression and anxiety. RESULTS: There was a significant time-by-group interaction (P < .01) for both immediate and delayed recall of paragraph length material. Contrasts showed a significant decline in memory for the pregnant group from the second to the third trimester (P < .01). No significant changes in memory were noted for the control group. The pregnant women scored higher on both depression and anxiety scales; however, somatic rather than cognitive items accounted for the elevated scores. Fluctuations in mood and memory did not coincide. CONCLUSION: There is a pregnancy-related decline in memory, which is limited to the third trimester. The decline is not attributable to depression, anxiety, sleep deprivation, or other physical changes associated with pregnancy.

Psychosocial dimensions of learning disabilities: external validation and relationship with age and academic functioning.

This study was designed to assess the following in a group of 152 children with learning disabilities between the ages of 7 and 13 years: (a) the relationships between age and psychosocial functioning: (b) the relationships among psychosocial functioning, cognitive abilities, and academic achievement; and (c) the external validity of statistically derived psychosocial subtypes. Participants were assigned to one of seven psychosocial subtypes on the basis of a profile-matching algorithm. Overall, the findings suggested no increase in psychopathology with advancing age. In addition, clear relationships were found between academic achievement patterns and personality subtypes. Finally, the subtypes could be distinguished on the basis of a behavior problem checklist not used for the construction of the subtypes.

Specificity of volumetric magnetic resonance imaging in detecting hippocampal sclerosis.

BACKGROUND: Magnetic resonance imaging (MRI)-based volumetric measurements of the hippocampal formation are useful in detecting unilateral hippocampal sclerosis (HS) in patients with temporal lobe epilepsy. In this pathologic entity, volumetric MRI analysis shows the epileptogenic structure to be atrophic when compared with the normal, nonepileptogenic side. Some authors have suggested that the radiological features of atrophy of medial temporal lobe structures are common in patients with complex partial seizures, but also are seen frequently in other seizure types and can occur even in patients without epilepsy. OBJECTIVE: To determine if seizures originating in extrahippocampal sites cause gliosis, cell loss, and atrophy of medial temporal lobe structures (i.e., HS). METHODS: We studied 110 patients with chronic epilepsy using volumetric MRI measurements of the hippocampal formation. Seventeen patients had pathologically proven HS, 27 patients had seizures due to extratemporal structural lesions, 15 patients had seizures caused by extrahippocampal temporal lobe lesions, 29 patients had primary generalized epilepsy, and 22 patients had secondary generalized epilepsy. RESULTS: All 17 patients with HS showed significantly reduced absolute hippocampal formation volumes of greater than 2 SDs below the mean of the control groups. The preoperative hippocampal formation volume measurements correlated well with the severity of HS on pathological examination. Hippocampal volumes were within the normal range in all patients with primary generalized epilepsy, secondary generalized epilepsy, extratemporal structural lesions, and extrahippocampal temporal lobe lesions. CONCLUSIONS: Seizures originating at extrahippocampal sites do not cause gliosis, cell loss, or atrophy of medial temporal structures. Significant reduction in hippocampal volumes is a specific marker for HS.

[15O]-water PET and intraoperative brain mapping: a comparison in the localization of eloquent cortex.

[15O]-water PET was performed on 12 patients with structural lesions for localization of the motor (n = 5), language (receptive and expressive; n = 6), and visual cortex (n = 1). All these patients underwent interactive image-guided surgery using an infrared digitizer and intraoperative electrical stimulation mapping for motor, sensory, language, and visual cortex location. MRI-PET coregistration was performed using a surface matching approach that integrated functional information with interactive image guidance during the surgical procedure. An awake craniotomy with motor and sensory intraoperative stimulation was performed using a registered bipolar electrode that was tracked on real-time during the surgical procedure. Intraoperative functional findings were displayed and saved on the registered MRI images. The sites of functional PET activation during the performance of motor, visual and language tasks were then compared to the results of intraoperative cortical stimulation in 11 patients and visual evoked potentials in one. The results of the PET activation studies were concordant with the findings of intraoperative stimulation in all cases. During resection of the structural lesions, intraoperative stimulation was continued in the subcortical pathways, and five patients had positive responses on areas not identified by the functional PET. Furthermore, 3 patients showed transitory changes in function (speech arrest 1, naming difficulty 1, and motor weakness 1) that were reversible after changing the dissection technique or a brain retractor. [15O]-water PET was reliable in identifying the motor, visual, and language cortex. Language-related rCBF increases were highly distributive, although only part of these activations were subjected to intraoperative stimulation. We conclude that [15O]-water PET can be used for preoperative noninvasive identification of functional cortex and may be useful in neurosurgical preplanning. Intraoperative mapping still remains the main means to avoid neurological damage as it can be performed during the entire surgical procedure to avoid damage to cortex, pathways, and damage secondary to ischemia or edema (brain retraction).

Verbal learning subtypes in traumatic brain injury: a replication.

Traumatic brain injury (TBI) has been associated with memory impairments, but the severity and qualitative aspects of such impairment do not appear homogeneous across patients. This study sought to replicate an earlier investigation that found distinct verbal learning subtypes in TBI using the California Verbal Learning Test (CVLT). CVLT data from 88 acute rehabilitation inpatients with mild, moderate, and severe traumatic brain injuries were analyzed with multiple cluster analytic techniques. Cluster analyses yielded five learning subtypes, three of which appeared similar to the subtypes previously identified as Active, Disorganized, and Passive subtypes, and two that appeared similar to the Deficient subgroup. Traumatic brain injury appears to be characterized by heterogeneous, but fairly reliable, verbal learning subtypes that can be detected early postinjury.

Psychosocial functioning of children with learning disabilities at three age levels.

In this study, the relationship between age and patterns of psychosocial functioning was investigated in a sample of 728 children with learning disabilities (LD). In the first part of the study, Young (7-8 years), Middle (9-10 years), and Old (11-13 years) children were subtyped by cluster analysis applied to scores on the Personality Inventory for Children (PIC). The subtypes that emerged at each age level were similar to those found in our previous research, and were comparable at each age level. In the second part of the study, children were classified within a PIC-based psychosocial typology developed in previous studies. When the subtypes were broken down by age category, the mean PIC profiles of Young, Middle, and Old children did not differ substantially in shape or elevation, and the proportions of Young, Middle, and Old children in each subtype were comparable. These results suggest that patterns of psychosocial functioning of children with LD are stable across ages 7-13 years and, overall, do not show increased psychopathology with increased age.

Psychosocial functioning of children: relations between personality subtypes and academic achievement.

Five hundred children from ages 6 to 12 who had been referred for neuropsychological assessment were clustered into six subtypes using a k-means technique applied to 10 PIC scales. Five of the six subtypes were virtually identical to subtypes identified in previous research (viz., normal, somatic concern, mild anxiety, externalized psychopathology, and internalized psychopathology). A sixth subtype (conduct disorder) was also found. Wide Range Achievement Test (WRAT) Reading and Spelling scores discriminated between normal, somatic concern, and conduct disorder subtypes on the one hand vs. the more disturbed externalized and internalized psychopathology subtypes on the other; the latter groups scored higher on these measures. The internalized psychopathology subtype also showed large discrepancies between reading vs. arithmetic and spelling vs. arithmetic. The results support the view that psychosocial functioning is related to assets and deficits in cognitive/academic functioning in children, and that particular patterns of such assets and deficits are related to particular forms of psychopathology.

Fibrous histiocytoid leprosy of the cornea.

We describe a 50-year-old man with a 10-year history of gradually enlarging limbal tumors and conjunctival injection. An excised limbal mass presented a diagnostic challenge histopathologically and was initially believed to be a fibrous histiocytoma. Special stains, however, revealed acid-fast organisms in the fibrous histiocytes, and the diagnosis was changed to corneal leproma. This case confirms the existence of fibrous histiocytoma-like lesions in leprosy, which in this form can be termed fibrous histiocytoid leprosy. Furthermore, it suggests the need for special stains to rule out infectious cause in lesions believed to be atypical fibrous histiocytomas.

Lateralizing value of transient hypofrontality during Wada's test.

Five of 22 subjects who underwent Wada's test in our institution over last year developed transient hypofrontality, always following the injection of the side contralateral to seizure focus (as defined by prior ictal recordings). This event may have lateralizing value and could well be because of pharmacological ablation of contralateral frontal-lobe combined with compromised ipsilateral frontal-lobe causing transient hypofrontality.

Event-related potentials in complex partial seizures.

Both early (N1 and P2) and late (N2 and P3) event-related potentials (ERP) were obtained in 16 patients with complex partial seizures, 12 with left hemispheric ictal focus and 4 with right, to see if they help in lateralizing the seizure focus, and also to determine if they correlate with behavioral (MMPI, Bear-Fedio), attentional (Trails A and B), cognitive (WAIS-R, Boston Naming, Warrington Word and Face recognition) and mental speed (Stroop color naming and reading) tasks. Early waves were more often lateralized than late waves but both were often falsely lateralizing. Early waves were better correlated with behavioral tasks whereas late waves were better with those measuring mental speed, attention and cognition. These data tentatively discourage the utility of ERP in preoperative lateralization of seizure focus but argue for their potential value in psychophysiological correlations.