Anti-N-Methyl-D-Aspartate Receptor-Mediated Encephalitis: Recent Advances in Diagnosis and Treatment in Children.

Anti-N-methyl-d-aspartate receptor-mediated encephalitis (anti-NMDAR encephalitis) is increasingly recognized in children and adolescents. There is a recognizable pattern of clinical symptoms, similar between children and adults. There are some differences in children including the frequency of presenting symptoms, the presence of hypoventilation, and the identification of an associated tumor. Early tumor removal and treatment with immunotherapy is important for rapid recovery. The prognosis can be surprisingly good but some children have lasting neurocognitive deficits.

L-745,870 reduces L-DOPA-induced dyskinesia in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned macaque model of Parkinson's disease.

L-DOPA-induced dyskinesia remains an unmet challenge in the treatment of Parkinson's disease (PD). Here, we investigate the potential antidyskinetic efficacy of 3-([4-(4-chlorophenyl)piperazin-1-yl]methyl)-1H-pyrrolo[2,3-b]pyridine (L-745,870), a potent and selective dopamine D(4) receptor antagonist with a good toxicology profile and an excellent safety and tolerability record in phase I/II clinical studies, for non-PD indications. Six macaques were rendered parkinsonian by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine administration. After induction of stable and marked dyskinesia, animals were administered acute challenges of L-745,870 in combination with L-DOPA. To guarantee D(4) selectivity at the doses used in the study, we determined the plasma, cerebrospinal fluid, and brain levels of L-745,870. Coadministration of L-745,870 (1 mg/kg) and L-DOPA significantly reduced the severity of dyskinesia, by up to 59%, in comparison with L-DOPA alone (P < 0.01). L-745,870 had no effect on the duration of antiparkinsonian benefit (ON-time) (P > 0.05). However, L-745,870 (1 mg/kg) significantly increased the duration of ON-time without disabling dyskinesia (+204%; P < 0.001) and decreased duration of ON-time with disabling dyskinesia compared with L-DOPA alone (-56%; P < 0.01). Brain levels of L-745,870 (∼600 ng/g) were within the range at which L-745,870 provides selective D(4) receptor antagonism. Plasma levels were comparable with those demonstrated to be well tolerated in human studies. These data suggest that selective D(4) receptor antagonists represent a potential therapeutic approach for L-DOPA-induced dyskinesia. It is noteworthy that L-745,870 has already undergone significant clinical development, has an excellent profile for a therapeutic candidate, and could be advanced rapidly to phase IIa clinical studies for dyskinesia in PD.

Suppressive effects of intrathecal granulocyte colony-stimulating factor on excessive release of excitatory amino acids in the spinal cerebrospinal fluid of rats with cord ischemia: role of glutamate transporters.

Recently, the hematopoietic factor, granulocyte colony-stimulating factor (G-CSF), has been shown to exhibit neuroprotective effects in CNS injuries. Our previous study demonstrated that intrathecal (i.t.) G-CSF significantly improved neurological defects in spinal cord ischemic rats. Considerable evidence indicates that the release of excessive amounts of excitatory amino acids (EAAs) plays a critical role in neuron injury induced by ischemic insult. In the present study, we used a spinal cord ischemia-microdialysis model to examine whether i.t. G-CSF exerted antiexcitotoxicity effects in a rat model of spinal cord ischemia. I.t. catheters and a microdialysis probe were implanted in male Wistar rats. The results revealed that spinal cord ischemia-induced neurological defects were accompanied by a significant increase in the concentration of EAAs (aspartate and glutamate) in the spinal dialysates from 30 min to 2 days after reperfusion. I.t administration of G-CSF immediately after the performance of surgery designed to induce ischemia led to a significant reduction in ischemia-induced increases in the levels of spinal EAAs. Moreover, i.t. G-CSF also brought about a significant reduction in the elevation of spinal EAA concentrations induced by exogenous i.t. administration of glutamate (10 microl of 500 mM). I.t. G-CSF attenuated spinal cord ischemia-induced downregulation of expression of three glutamate transporters (GTs), glial transporter Glu-Asp transporter (GLAST), Glu transporter-1 (GLT-1), and excitatory amino acid carrier 1 (EAAC1) protein 48 h after spinal cord ischemic surgery. Immunohistofluorescent staining showed that i.t. G-CSF significantly upregulated expression of the three GTs in the gray matter of the lumbar spinal cord from 3 to 24 h after injection. We propose that i.t. G-CSF possesses an ability to reduce the extent of spinal cord ischemia-induced excitotoxicity by inducing the expression of glutamate transporters.

Hemichorea-hemiballismus associated with nonketotic hyperglycemia: a possible role of inflammation.

Three cases of hemichorea-hemiballismus (HC-HB) associated with nonketotic hyperglycemia were reported. Of them two patients presented as HC-HB and the remaining one as generalized chorea-ballismus (CB). Brain MRI showed characteristic T1-weighted high-intensity lesions in the contralateral or bilateral striatum without edema or mass effect. They all had a prior history of respiratory or urinary infection. Cerebrospinal fluid test in two patients showed an elevation of protein concentration with normal cell and an increased IgG content and elevated IgG index or 24 h IgG intrathecal synthesis rate. These results suggested that inflammation within the central nervous system may participate in the pathogenesis of chorea and ballismus induced by NKH.

The expanding phenotype of GLUT1-deficiency syndrome.

Transport of glucose from the bloodstream across the blood-brain barrier to the central nervous system is facilitated by glucose transport protein type 1 (GLUT1), the first member of the solute carrier family 2 (SLC2). Heterozygous mutations in the GLUT1/SLC2A1 gene, occurring de novo or inherited as an autosomal dominant trait, result in cerebral energy failure and a clinical condition termed GLUT1-deficiency syndrome (GLUT1-DS). Clinical features usually comprise motor and mental developmental delay, seizures with infantile onset, deceleration of head growth often resulting in acquired microcephaly, and a movement disorder with ataxia, dystonia, and spasticity. Subsequent to the delineation of this classic phenotype the variability of signs and symptoms in GLUT1-DS is being recognized. Patients with (i) carbohydrate-responsive symptoms, with (ii) predominant ataxia or dystonia, but without seizures, and with (iii) paroxysmal exertion-induced dyskinesia and seizures have been reported. Common laboratory hallmark in all phenotypes is the reduced glucose level in cerebrospinal fluid with lowered CSF-to-blood glucose ratio. Treatment with a ketogenic diet results in marked improvement of seizures and movement disorders.

[Hemichorea-hemiballism associated to cryptococcal granuloma in a patient with AIDS: case report]. / Hemicoréia-hemibalismo associado a granuloma criptocócico em paciente com SIDA: relato de caso.

Movement disorders are not common in acquired immunodeficiency syndrome. Hemichorea-hemiballism (HC-HB) is the most common of them all, and it is usually related to oportunistic toxoplasmosis of the basal ganglia. We present a 28-year-old man, HIV positive with HC-HB caused by a right subthalamic granuloma, which did not respond to treatment for toxoplasmosis. Cryptoccococic antigen was positive in the cerebrospinal fluid and antifungic therapy led to clinical and radiologic improvement, thus the diagnosis of a granulomatous lesion by Cryptococcus neoformans was established. Current literature on HC-HB and its relationship with AIDS is subsequently reviewed.