Sang-Wuk Jeong

Early treadmill training promotes motor function after hemorrhagic stroke in rats.

Rehabilitation after a stroke is very important because it has beneficial effects on brain function, including the promotion of plasticity. However, an optimal time window for rehabilitation interventions after hemorrhagic stroke has not been clearly defined. The aim of this study was to determine whether early exercise training initiated 24h after an intracerebral hemorrhage (ICH) might enhance neurologic recovery more than exercise initiated 1 week after ICH without hematoma expansion and edema volume increase. We subjected adult male Sprague-Dawley rats to experimental ICH by the intrastriatal administration of bacterial collagenase. The rats were randomly divided into the following 2 groups: early training group (treadmill exercise started 24h post-ICH; n=18) and late training group (treadmill exercise started 1-week post-ICH; n=18). Two weeks after surgery we performed neurologic tests (rota-rod, modified limb-placing, and adhesive-dot removal tests), and measured hematoma volumes and brain water content. In the late training group, compared with the pre-ICH performance on the rota-rod test (98.3+/-69.4s), the animals had significantly worse performance after the post-ICH rehabilitation (40.5+/-52.6s; p<0.01, paired t-test). In the early training group however, the motor performance after the post-ICH rehabilitation (56.4+/-73.5s) was not significantly different from the baseline pre-ICH performance (79.8+/-33.9s; p=0.24). There were no significant differences between the two groups with respect to the other neurologic tests. Early exercise did not increase hematoma size or brain water content. Early treadmill training could be performed safely, and enhanced motor recovery in a rat model of ICH. Further studies are required to translate the results into clinical significance.

Dysbindin gene variants are associated with bipolar I disorder in a Korean population.

The dysbindin gene (DTNBP1) has been associated with schizophrenia in several populations. Because the clinical characteristics of schizophrenia and bipolar disorder overlap in many respects and findings from genetic studies have suggested common genes between them, we conducted a case control association study of bipolar disorder in Korea to investigate the genetic association between DTNBP1 and bipolar disorder. In total, 163 patients with bipolar disorder and 350 controls were evaluated. We genotyped three single nucleotide polymorphisms of DTNBP1 (SNP A, P1763, and P1320) and analyzed the allele, genotype, and haplotype associations with bipolar disorder. We found significant genotypic associations with P1763 and P1320, but no association with SNP A in the bipolar I group. When we included bipolar II and schizoaffective disorder in the affected phenotype, the significance decreased. A positive association was observed between the SNP A-P1763 haplotype and the bipolar I phenotype. This haplotype association was lost when we either broadened our phenotype or included P1320 in a haplotype. The positive results of the present study lost significance after a Bonferroni correction for multiple testing. These findings are consistent with previous findings that showed a positive association of DTNBP1 with bipolar disorders. Moreover, our results suggest that DTNBP1 may contribute more to bipolar I disorder than bipolar II disorder or schizoaffective disorder. Further comprehensive studies will be required to clarify these association, however, it seems likely that DTNBP1 is a susceptibility gene for bipolar disorder.

Effects of the ketogenic diet on neurogenesis after kainic acid-induced seizures in mice

The ketogenic diet (KD) remains a therapy in search of explanation although it is an established treatment of intractable epilepsy. Recent studies suggest that the KD may be both anticonvulsant and antiepileptogenic. Epileptic seizures have been shown to stimulate the proliferation rate of neuronal progenitor cells in adult animals, which may be related to epileptogenesis. It is known that calorie restriction (CR) increases neurogenesis. The KD was originally formulated to reproduce the biochemical changes seen upon fasting (extreme CR). Thus, we investigated the effects of the KD on neurogenesis after kainic acid (KA)-induced seizures in mice. In the present study, quantitative analysis of BrdU labeling revealed a significant increase in the proliferation rate of neuronal progenitor cells after KA-induced seizures in the KD-fed mice. This finding may provide a clue to explain how the KD exerts antiepileptogenic effects although further studies are mandatory to elucidate the relationship between seizure-induced neurogenesis augmented by the KD and its antiepileptogenic properties. In conclusion, our results suggest that the KD enhances neurogenesis, which may be related to its beneficial effects on epilepsy.

Occipital Neuralgia as the Only Presenting Symptom of Foramen Magnum Meningioma

Background Occipital neuralgia (ON) is a condition characterized by a paroxysmal stabbing pain in the area of the greater or lesser occipital nerves; it is usually regarded by clinicians as idiopathic. Some have suggested that ON can be induced by trauma or injury of the occipital nerves or their roots, but tumor has rarely been reported as a cause of ON. Case Report We report herein a case of foramen magnum meningioma in a 55-year-old woman who presented with ON triggered by head motion as the only symptom without any signs of myelopathy. Conclusions This case indicates that it is important to consider the underlying causes of ON. Precise neurologic and radiological evaluations such as cervical spine magnetic resonance imaging are needed.

NINJ2 SNP may affect the onset age of first-ever ischemic stroke without increasing silent cerebrovascular lesions

BackgroundTo investigate if single nucleotide polymorphisms on chromosome 12p13 and within 11 kb of the gene NINJ2 would be associated with earlier-onset (vs. late-onset) first-ever ischemic stroke and increase silent cerebrovascular lesions prior to the manifestation of the stroke.MethodsWe prospectively enrolled 164 patients (67.6 ± 12.9 years, 92 men) admitted with first-ever ischemic strokes. All patients underwent genotyping of rs11833579 and rs12425791 as well as systemic investigations including magnetic resonance (MR) imaging and other vascular workup. Stroke-related MR lesions were registered on a brain-template-set using a custom-built software package Image_QNA: high-signal-intensity ischemic lesions on diffusion, T2-weighted, or fluid attenuation inversion recovery (FLAIR) MR images, and low signal intensity hemorrhagic lesions on gradient-echo MR images.ResultsThe rs11833579 A/A or G/A genotype was independently associated with the first-ever ischemic stroke before the age 59 vs. 59 or over, after adjusting for cardiovascular risk factors and prior medication of antiplatelet or anticoagulant drugs, increasing the risk by about 2.5 fold. In the quantitative MR lesion maps from age-sex matched subgroups (n = 124 or 126), there was no difference between the patients with the rs11833579 A/A or G/A genotype and those with the G/G genotype. Unexpectedly, the extent of leukoaraiosis on FLAIR-MR images tended to be smaller in the corona radiata and centrum semiovale of the patients with the rs12425791 A/A or G/A genotype than in those with the G/G genotype (P = 0.052). Neither the rs11833579 nor the rs12425791 genotype significantly affected initial stroke severity; however the latter was associated with relatively low modified Rankin scale scores at 1 year after stroke.ConclusionsThe rs11833579 A/A or G/A genotype may bring forward the onset age of first-ever ischemic stroke without increasing silent cerebrovascular lesions prior to the stroke. Further studies are required to confirm our preliminary findings.

Mapping the Supratentorial Cerebral Arterial Territories Using 1160 Large Artery Infarcts

Importance Cerebral vascular territories are of key clinical importance in patients with stroke, but available maps are highly variable and based on prior studies with small sample sizes. Objective To update and improve the state of knowledge on the supratentorial vascular supply to the brain by using the natural experiment of large artery infarcts and to map out the variable anatomy of the anterior, middle, and posterior cerebral artery (ACA, MCA, and PCA) territories. Design, Setting, and Participants In this cross-sectional study, digital maps of supratentorial infarcts were generated using diffusion-weighted magnetic resonance imaging (MRI) of 1160 patients with acute (<1-week) stroke recruited (May 2011 to February 2013) consecutively from 11 Korean stroke centers. All had supratentorial infarction associated with significant stenosis or occlusion of 1 of 3 large supratentorial cerebral arteries but with patent intracranial or extracranial carotid arteries. Data were analyzed between February 2016 and August 2017. Main Outcomes and Measures The 3 vascular territories were mapped individually by affected vessel, generating 3 data sets for which infarct frequency is defined for each voxel in the data set. By mapping these 3 vascular territories collectively, we generated data sets showing the Certainty Index (CI) to reflect the likelihood of a voxel being a member of a specific vascular territory, calculated as either ACA, MCA, or PCA infarct frequency divided by total infarct frequency in that voxel. Results Of the 1160 patients (mean [SD] age, 67.0 [13.3] years old), 623 were men (53.7%). When the cutoff CI was set as 90%, the volume of the MCA territory (approximately 54% of the supratentorial parenchymal brain volume) was about 4-fold bigger than the volumes of the ACA and PCA territories (each approximately 13%). Quantitative studies showed that the medial frontal gyrus, superior frontal gyrus, and anterior cingulate were involved mostly in ACA infarcts, whereas the middle frontal gyrus and caudate were involved mostly by MCA infarcts. The PCA infarct territory was smaller and narrower than traditionally shown. Border-zone maps could be defined by using either relative infarct frequencies or CI differences. Conclusions and Relevance We have generated statistically rigorous maps to delineate territorial border zones and lines. The new topographic brain atlas can be used in clinical care and in research to objectively define the supratentorial arterial territories and their borders.