Editing the Sickle Cell Disease Mutation in Human Hematopoietic Stem Cells: Comparison of Endonucleases and Homologous Donor Templates.

Site-specific correction of a point mutation causing a monogenic disease in autologous hematopoietic stem and progenitor cells (HSPCs) can be used as a treatment of inherited disorders of the blood cells. Sickle cell disease (SCD) is an ideal model to investigate the potential use of gene editing to transvert a single point mutation at the ß-globin locus (HBB). We compared the activity of zinc-finger nucleases (ZFNs) and CRISPR/Cas9 for editing, and homologous donor templates delivered as single-stranded oligodeoxynucleotides (ssODNs), adeno-associated virus serotype 6 (AAV6), integrase-deficient lentiviral vectors (IDLVs), and adenovirus 5/35 serotype (Ad5/35) to transvert the base pair responsible for SCD in HBB in primary human CD34+ HSPCs. We found that the ZFNs and Cas9 directed similar frequencies of nuclease activity. In vitro, AAV6 led to the highest frequencies of homology-directed repair (HDR), but levels of base pair transversions were significantly reduced when analyzing cells in vivo in immunodeficient mouse xenografts, with similar frequencies achieved with either AAV6 or ssODNs. AAV6 also caused significant impairment of colony-forming progenitors and human cell engraftment. Gene correction in engrafting hematopoietic stem cells may be limited by the capacity of the cells to mediate HDR, suggesting additional manipulations may be needed for high-efficiency gene correction in HSPCs.

Bilateral Hypertrophic Olivary Degeneration and Holmes Tremor without Palatal Tremor: An Unusual Association.

BACKGROUND: Lesions in the Guillain-Mollaret triangle or dentate-rubro-olivary pathway may lead to hypertrophic olivary degeneration (HOD), a secondary trans-synaptic degeneration of the inferior olivary nucleus. HOD is usually associated with palatal tremor and rarely with Holmes tremor. Bilateral HOD is a very unusual condition and very few cases are reported. CASE REPORT: We report here two cases of bilateral HOD after two different vascular lesions located at the decussation of superior cerebellar peduncles, thus impairing both central tegmental tracts and interrupting bilaterally the dentate-rubral-olivary pathway. Interestingly, both developed bilateral Holmes tremor but not palatal tremor. DISCUSSION: Lesions in some of the components in the Guillain-Mollaret triangle may develop Holmes tremor with HOD and without palatal tremor. Magnetic resonance imaging is an invaluable tool in these cases. Better understanding of the pathways in this loop is needed.

Hemichorea/Hemiballism Associated with Hyperglycemia: Report of 20 Cases.

BACKGROUND: Hemichorea/hemiballism associated with nonketotic hyperglycemia is a well-recognized syndrome, but few case series have been reported in the literature. CASE REPORT: We describe 20 patients with hemichorea/hemiballism associated with hyperglycemia (9 males and 11 females) with mean age of 67.8 years. Ten patients had a previous diagnosis of type 2 diabetes mellitus, and one had type 1 diabetes mellitus. Six of them had documentation of poor diabetic control over at least the last 3 months. Nine patients had new-onset hyperglycemia with a diagnosis of diabetes mellitus made after discharge. Seventeen patients had unilateral chorea/ballism, while three had bilateral chorea/ballism. Eighteen cases had striatal hyperdensities on computed tomography (CT) and/or hyperintense signals on magnetic resonance imaging (MRI). The putamen was affected in all cases, and the caudate nucleus was involved in nine. DISCUSSION: Hemichorea/hemiballism associated with nonketotic hyperglycemia can be the presenting sign of diabetes mellitus in almost half of cases or can occur after a few months of poor glycemic control in patients with diagnosed diabetes. This case series is one of the largest to date and adds valuable information about clinical and neuroimaging features that are comparable with published data but also emphasize the role of adequate diabetes mellitus control.

Holmes tremor: Clinical description, lesion localization, and treatment in a series of 29 cases.

OBJECTIVE: To describe the clinical features, etiology, findings from neuroimaging, and treatment results in a series of 29 patients with Holmes tremor (HT). METHODS: A retrospective study was performed based on review of medical records and videos of patients with HT diagnosis. RESULTS: A total of 16 women and 13 men were included. The mean age at the moment of CNS insult was 33.9 ± 20.1 years (range 8-76 years). The most common causes were vascular (48.3%), ischemic, or hemorrhagic. Traumatic brain injury only represented 17.24%; other causes represented 34.5%. The median latency from lesion to tremor onset was 2 months (range 7 days-228 months). The most common symptoms/signs associated with HT were hemiparesis (62%), ataxia (51.7%), hypoesthesia (27.58%), dystonia (24.1%), cranial nerve involvement (24.1%), and dysarthria (24.1%). Other symptoms/signs were vertical gaze disorders (6.8%), bradykinesia/rigidity (6.8%), myoclonus (3.4%), and seizures (3.4%). Most of the patients had lesions involving more than one area. MRI showed lesions in thalamus or midbrain or cerebellum in 82.7% of the patients. Levodopa treatment was effective in 13 out of 24 treated patients (54.16%) and in 3 patients unilateral thalamotomy provided excellent results. CONCLUSIONS: The most common causes of HT in our series were vascular lesions. The most common lesion topography was mesencephalic, thalamic, or both. Treatment with levodopa and thalamic stereotactic lesional surgery seems to be effective.

Reply #1 to: Glycemic Choreoballism.

In Response To: Lee D, Ahn TB. Glycemic choreoballism. Tremor Other Hyperkinet Mov. 2016; 6. doi: 10.7916/D8QJ7HNF Original Article: Cosentino C, Torres L, Nuñez Y, et al. Hemichorea/hemiballism associated with hyperglycemia: report of twenty cases. Tremor Other Hyperkinet Mov. 2016; 6. doi: 10.7916/D8DN454P.

Holmes tremor secondary to brainstem hemorrhage responsive to levodopa: report of 2 cases.

We report 2 patients who presented a brainstem hemorrhage and who, after 1 and 6 months, respectively, developed a 4-Hz postural and resting tremor consistent with Holmes tremor, which severely interfered with the activities of daily living. In both cases, levodopa dramatically improved the tremor. Pharmacological treatment of this condition is usually disappointing, and surgical procedures are commonly required for severe cases. Our patients, together with 13 others gleaned from the literature, suggest that in cases of Holmes tremor secondary to brainstem hemorrhage, levodopa can be a useful treatment, and it should be tested before considering invasive therapies.

Cysticercosis lesions in basal ganglia are common but clinically silent.

Movement disorders due to basal ganglia involvement by neurocysticercosis are rarely seen. To evaluate the frequency of basal ganglia location of cysticercotic cysts and its clinical manifestations, baseline MRI scans of 120 consecutive patients with active neurocysticercosis were reviewed and the presence and number of active cysticercosis lesions (viable cysts or enhancing lesions) in the basal ganglia were recorded and correlated with demographic and clinical data. Basal ganglia involvement was found in 32 cases (26.7%). The frequency of lesions in basal ganglia was related to the total number of lesions, ranging from 5% of patients with a single cysticerci, to 60% in patients with more than five parasites. Putamen and caudate nuclei were the most frequent sites of lesions. No significant difference between both hemispheres was observed. Basal ganglia localization is common in neurocysticercosis but it is rarely associated with clinical manifestations.