Comparison of the ability of different quantitative indices in 123I-FP-CIT single-photon emission computed tomography to differentiate dopaminergic neurodegenerative disease.

PURPOSE: By imaging dopamine transporter (DAT) uptake in the striatum, 123I-FP-CIT SPECT can differentiate dopaminergic neurodegenerative disease (dNDD) and non-dNDD, which differ in pathophysiology and clinical management. Our aim was to compare and validate the diagnostic abilities of various 123I-FP-CIT SPECT quantitative indices for dNDD. MATERIALS AND METHODS: Distribution volume ratio (DVR) and binding ratio (BR), measures of DAT uptake capacity, were measured by analyzing clinical 123I-FP-CIT SPECT images of 29 patients with dNDD, including dementia with Lewy bodies and Parkinson's disease, and 18 patients with non-dNDD, using Montreal Neurological Institute space-based anatomical standardization and an atlas template, which utilizes statistical parametric mapping. Additionally, we computed the specific binding ratio (SBR) based on Bolt's method and the maximum and mean standardized uptake values (SUVmax and SUVmean, respectively). RESULTS: The caudate-to-occipital lobe, putamen-to-occipital lobe, and striatum-to-occipital lobe ratios (COR, POR, and SOR, respectively) on DVR and POR and SOR on BR were significantly lower in dNDD than in non-dNDD, with areas under the ROC curve (AUCs) of 0.941-0.960, showing high diagnostic accuracy for dNDD. However, the AUC of COR on BR was 0.839, indicating lower diagnostic performance. SBR had an AUC of 0.921, while SUVmax and SUVmean had AUCs of 0.906 and 0.900, respectively. Although striatal asymmetry on both DVR and BR exhibited AUCs of 0.728 and 0.734 and asymmetry on SBR showed an AUC of 0.757, the ratio-based DAT quantitative indices were superior. There were strong positive correlations of DVR with BR, DVR with SBR or SUVmax, BR with SBR or SUVmax, and SBR with SUVmax. CONCLUSION: COR, POR, and SOR on DVR and POR and SOR on BR were the most useful DAT quantitative indices. These indices can be compared with SBR and SUV, suggesting that comprehensive evaluation improves the diagnostic accuracy of dNDD.

[Drugs for Neurogenic Bladder Dysfunction].

Urinary dysfunction includes an overactive bladder (OAB), post-void residual (PVR)/retention, or both entities. Brain diseases cause OAB, peripheral neuropathies are associated with significant PVR/retention, and multisystem atrophy/spinal cord diseases result in a combination of OAB and PVR/retention. Selective beta 3 adrenergic receptor agonists or anticholinergic agents are the first-choice treatment for OAB and clean intermittent self-catheterization, alpha-blocker and cholinergic stimulant therapy for significant PVR/retention. These therapies may be useful to maximize patients' quality of life and prevent serious complications, such as urosepsis or kidney dysfunction.

How brain diseases affect the lower urinary tract function?

This article reviewed brain mechanism of the lower urinary tract (LUT). Among autonomic nervous systems, LUT is unique in terms of afferent pathophysiology; bladder sensation is perceived soon after the storage phase and throughout the voiding phase. Within the brain, this is measured in experimental animals by the firing of single neurons and in humans by evoked potentials/functional neuroimaging. The evidence indicates that sphincter information goes up to the precentral motor cortex and other brain areas, and bladder information goes up to the insular cortex (IC)/anterior cingulate (ACG) and further to the prefrontal cortex (PFC). Another LUT-specific phenomenon is efferent pathophysiology: detrusor overactivity (exaggerated micturition reflex) occurs in brain diseases such as stroke (focal disease) and dementia with Lewy bodies (diffuse diseases, may overlap with each other). With the turning off and on of the brain-switch of micturition (at the periaqueductal gray [PAG]), there is a bladder-inhibitory PFC-IC/ACG-hypothalamus-PAG pathway, with interconnections via the PFC with a PFC-nigrostriatal D1 dopaminergic pathway and a PFC-cerebellar pathway. Brain diseases that affect these areas may cause a loss of the brain's inhibition of the micturition reflex, leading to detrusor overactivity. This has a significant clinical impact on patients and requires appropriate management.

[New MDS Criteria for the Diagnosis of Multiple System Atrophy: An Autonomic Viewpoint].

We reviewed the autonomic dysfunction in multiple system atrophy (MSA) with reference to the new MDS criteria. MSA is a major neurodegenerative disorder that presents with autonomic and motor dysfunctions (cerebellar ataxia and/or parkinsonism). Autonomic dysfunction in MSA affects urinary, cardiac, gastrointestinal, otorhinolaryngologic, and respiratory functions. Therefore, autonomic dysfunction in MSA should be recognized, collaborating with each faculty for the treatment and care of the patients. Moreover, it is highly recommended that neurologists request for an ultrasound measurement of the post-void residual urine volume. MSA has no cure; hence, active participation in the treatment and care of autonomic dysfunction in MSA patients is warranted.

Varicella-zoster virus infection and autonomic dysfunction.

BACKGROUND AND PURPOSE: Autonomic dysfunction has been occasionally described in varicella-zoster virus (VZV) infection, while few systematic reviews are available. We systematically review autonomic dysfunction due to VZV infection. METHODS: This study followed the PRISMA guideline, and three databases were researched and included cross-sectional studies in full-length publications in the English language using appropriate search keywords. RESULTS: A total of 102 articles were identified initially; finally 45 studies were used for review, comprising pupillomotor dysfunction in 4, sudomotor dysfunction in 2, cardiovascular dysfunction in 2, gastrointestinal dysfunction in 14, and urogenital dysfunction in 23. They can be summarized as (1) VZV infection rarely produces orthostatic hypotension, which involves diffuse sympathetic dysfunction by polyneuropathy. (2) In contrast, VZV infection produces dysfunction of the bladder and the bowel, which involves segmental parasympathetic or sympathetic dysfunction by dorsal root ganglionopathy. CONCLUSIONS: Awareness of VZV-related autonomic dysfunction is important, because such patients may first visit a gastroenterology or urology clinic. Close collaboration among neurologists, dermatologists, gastroenterologists, and urologists is important to start early antiviral agents and maximize bowel and bladder care in such patients.

Novel heterozygous variants of SLC12A6 in Japanese families with Charcot-Marie-Tooth disease.

BACKGROUND: Recessive mutations in SLC12A6 have been linked to hereditary motor sensory neuropathy with agenesis of the corpus callosum. Patients with early-onset peripheral neuropathy associated with SLC12A6 heterozygous variants were reported in 2016. Only five families and three variants have been reported to date, and the spectrum is unclear. Here, we aim to describe the clinical and mutation spectra of SLC12A6-related Charcot-Marie-Tooth (CMT) disease in Japanese patients. METHODS: We extracted SLC12A6 variants from our DNA microarray and targeted resequencing data obtained from 2598 patients with clinically suspected CMT who were referred to our genetic laboratory by neurological or neuropediatric departments across Japan. And we summarized the clinical and genetic features of these patients. RESULTS: In seven unrelated families, we identified one previously reported and three novel likely pathogenic SLC12A6 heterozygous variants, as well as two variants of uncertain significance. The mean age of onset for these patients was 17.5 ± 16.1 years. Regarding electrophysiology, the median motor nerve conduction velocity was 39.6 ± 9.5 m/sec. For the first time, we observed intellectual disability in three patients. One patient developed epilepsy, and her brain MRI revealed frontal and temporal lobe atrophy without changes in white matter and corpus callosum. CONCLUSIONS: Screening for the SLC12A6 gene should be considered in patients with CMT, particularly those with central nervous system lesions, such as cognitive impairment and epilepsy, regardless of the CMT subtype.

Female Urinary Retention Progressing to Possible Multiple System Atrophy-cerebellar Form after 12 Years.

We herein report a 73-year-old Japanese woman with possible multiple system atrophy-cerebellar form (MSA-C) who suffered from urinary retention (sacral autonomic disorder) for 12 years before exhibiting cerebellar ataxia. A peculiar combination of findings on urodynamics and sphincter electromyography (EMG), e.g. detrusor hyperactivity with impaired contraction (DHIC), detrusor-sphincter dyssynergia (DSD) and neurogenic sphincter EMG (upper and lower neuron-type autonomic dysfunction), seems to have been predictive of future development of MSA.

DRD2 Taq1A Polymorphism-Related Brain Volume Changes in Parkinson's Disease: Voxel-Based Morphometry.

Taq1A polymorphism is a DRD2 gene variant located in an exon of the ANKK1 gene and has an important role in the brain's dopaminergic functions. Some studies have indicated that A1 carriers have an increased risk of developing Parkinson's disease (PD) and show poorer clinical performance than A2 homo carriers. Previous studies have suggested that A1 carriers had fewer dopamine D2 receptors in the caudate and increased cortical activity as a compensatory mechanism. However, there is little information about morphological changes associated with this polymorphism in patients with PD. The study's aim was to investigate the relationship between brain volume and Taq1A polymorphism in PD using voxel-based morphometry (VBM). Based on Taq1A polymorphism, 103 patients with PD were divided into two groups: A1 carriers (A1/A1 and A1/A2) and A2 homo carriers (A2/A2). The volume of the left prefrontal cortex (PFC) was significantly decreased in A2 homo carriers compared to A1 carriers. This finding supports the association between Taq1A polymorphism and brain volume in PD and may explain the compensation of cortical function in A1 carriers with PD.

Increased biological antioxidant potential in the cerebrospinal fluid of transient global amnesia patients.

Oxidative stress may accompany the pathological process in transient global amnesia (TGA). We measured the biological antioxidant potential (BAP) in the cerebrospinal fluid (CSF) of TGA patients. We enrolled 13 TGA patients (7 men, 6 women; mean age 65.0 years [48-70 years]) and 24 control subjects (12 men, 12 women; mean age 38.2 years [17-65 years]; age did not correlate with csfBAP in this group). We performed brain MRI in all TGA patients, and CA1 lesions were noted by MRI in 5 subjects. We measured csfBAP, total antioxidant properties, in all TGA patients and controls. csfBAP levels were higher in TGA patients than in controls (p = 0.024, 0.028). csfBAP levels in TGA patients did not differ between MRI-positive and -negative subgroups. Elevated csfBAP levels were observed in TGA patients, suggesting that oxidative stress may have a role in the pathogenesis of TGA.

High levels of serum interleukin-6 are associated with disease activity in myasthenia gravis.

Myasthenia gravis (MG), a neuromuscular junction disorder, is caused by pathogenic autoantibodies. Interleukin-6 (IL-6) plays important roles in T helper 17 (Th17), T follicular helper (Tfh), and B cell activations as well as in antibody production. This study aimed to evaluate the clinical significance of serum IL-6 level as a biomarker of disease activity in patients with anti-acetylcholine receptor (AChR) antibody-positive MG. In the present study, serum IL-6 levels were measured in 93 treatment-naïve patients with anti-AChR antibody-positive MG and compared with those in 101 controls. Moreover, correlations between serum IL-6 levels and clinical characteristics were analyzed. Serum IL-6 levels were significantly higher in patients with anti-AChR antibody-positive MG than in controls (median [interquartile range], 2.5 [1.5-8.3] pg/mL vs. 1.5 [1.5-3.2] pg/mL, P < 0.001). The serum levels were correlated with the MG Foundation of America clinical classification (Spearman's ρ = 0.27; P < 0.01) and decreased following immunosuppressive treatment in parallel with disease activity (P = 0.01). In conclusion, IL-6 is involved in the pathogenesis of anti-AChR antibody-positive MG and could be a therapeutic target in MG.

Severe orthostatic hypotension associated with lesions of the area postraema in neuromyelitis optica spectrum disorder.

Hiccups, nausea and vomiting are known as the clinical manifestations of neuromyelitis optica spectrum disorder (NMOSD) linked to lesions of the area postraema in the medullary tegmentum. Here, we describe a 74-year-old male patient with NMOSD who presented with recurrent syncope due to severe orthostatic hypotension (OH) following symptoms of hiccups, nausea and vomiting. Brain magnetic resonance imaging revealed the lesion of the area postraema and it could be responsible for the symptom of OH. Considering the numerous related reports, we suspect that the prevalence of OH is underreported in the patients with NMOSD. OH may transition into more serious conditions, so it should be evaluated carefully in all patients with NMOSD, particularly when there is a lesion of the area postraema.

Gene expression profiling of the spinal cord at the chronic pain phase identified CDKL5 as a candidate gene for neural remodeling.

BACKGROUND: Chronic pain is a highly refractory and complicated condition that persists even without nociception. Several genome-wide gene expression analyses have shown that the immune response and inflammatory cytokines affect chronic pain establishment in the acute pain phase. However, compared with the acute phase, the chronic phase has a poorly elucidated gene expression profile. This study aimed to determine the gene expression profile in the spinal cord of a neuropathic pain mouse model in the chronic phase to elucidate the chronic pain characteristics. METHODS: We established a sciatic nerve cuff mouse model as a neuropathic pain model by placing a 2-mm section of a split PE-20 polyethylene tube around the sciatic nerve. The spinal cord was harvested at the L4-6 level at 28 postoperative days. Next, we examined differentially expressed genes (DEGs) through RNA sequencing (RNA-seq) compared with the sham group; moreover, we conducted enrichment analyses of the expressed genes. To reveal the chronic pain characteristics, we compared the gene expression profiles of the spinal cord between the acute and chronic phases in the neuropathic pain model. Among the chronic pain-related genes categorized in the dendrites, we focused on cyclin-dependent kinase-like 5 (CDKL5). We analyzed CDKL5 expression and function using real-time polymerase chain reaction (PCR), immunohistochemistry, and neurite extension assay in Neuro 2a (N2a) cells. We used three types of CDKL5 plasmids: wild type, nuclear localization signal-attached, and K42R kinase-dead CDKL5. RESULTS: We identified 403 DEGs, including 104 upregulated and 43 downregulated genes (false discovery rate < 0.01). Rather than inflammation or immune response, the most enriched terms in the chronic phase were "regulation of plasma membrane-bounded cell projection organization" and "dendrite." Real-time PCR assay confirmed increased CDKL5 expression in the ipsilateral dorsal horn. CDKL5 was broadly expressed in the ipsilateral dorsal horn across all layers. The neurite extension assay revealed that the cytoplasmic kinase function of CDKL5 was necessary for neurite outgrowth in N2a cells. CONCLUSION: RNA-seq of the spinal cord revealed that the most enriched genes during the chronic pain phase were involved in regulating axon and dendrite morphogenesis, including CDKL5. Our findings suggest that neural remodeling affects chronic pain establishment. Since patients with CDKL5 mutations have shown reduced pain perception, our findings suggest that CDKL5 in the spinal cord could result in neural remodeling during the chronic pain phase through cytoplasmic kinase activity.

Facial onset amyotrophic lateral sclerosis with K3E variant in the Cu/Zn superoxide dismutase gene.

We describe a 48-year-old man, suffering from difficulties in closing his eyes. He subsequently experienced progressive weakness in the facial and bulbar regions and upper limbs. His father and paternal grandmother had limb weakness as initial manifestations and were diagnosed with amyotrophic lateral sclerosis (ALS). In the present case, neuroimaging and laboratory studies were unremarkable, and neurophysiological studies disclosed diffuse denervation. Genetic testing identified a heterozygous c.10A>G, p.K4E (K3E) variant in superoxide dismutase 1 (SOD1) gene, and he was diagnosed with familial ALS. In ALS, facial muscles are rarely involved as an initial symptom. The present patient is a first case of facial onset ALS with K3E variant in SOD1 gene. Two case reports identified facial palsy as an initial manifestation in familial ALS with C6G variant in SOD1 gene. Several ALS patients with variants in SOD1 gene may have facial onset history.

Split hand and motor axonal hyperexcitability in spinal and bulbar muscular atrophy.

OBJECTIVE: The 'split hand' sign refers to preferential wasting of the thenar and first dorsal interosseous muscles with relatively sparing of the hypothenar muscles in amyotrophic lateral sclerosis (ALS) and both cortical and spinal/peripheral excitotoxic mechanisms have been proposed. We aimed to study split hand and axonal excitability in spinal and bulbar muscular atrophy (SBMA) in which cortical motor neurons are intact. METHODS: In 35 patients with genetically confirmed SBMA, 55 with ALS, 158 with other neuromuscular diseases and 90 normal controls; split hand was strictly determined by amplitudes of compound muscle action potentials. Nerve excitability testing of median motor axons was performed in 35 SBMA and 55 patients with ALS and 45 normal controls. RESULTS: Split hand was as frequently found for patients with SBMA (57%) and ALS (62%), compared with disease (20%) and normal (0%) controls. Excitability testing showed that in both SBMA and ALS, strength-duration time constant was longer, and threshold changes in depolarising threshold electrotonus and superexcitability in the recovery cycle were greater than in normal controls (p<0.01). CONCLUSIONS: Split hand is not specific to ALS and can be caused by the peripheral mechanism alone in SBMA, whereas the effect of upper motor neuron lesion cannot be excluded in ALS. Our results also suggest that SBMA and ALS share common axonal excitability changes; increased nodal persistent sodium and reduced potassium currents that may accelerate motor neuronal death and differently affect axons-innervating different muscles. Ion channel modulators could be a therapeutic option for both SBMA and ALS.

Monoamine oxidase B rs1799836 G allele polymorphism is a risk factor for early development of levodopa-induced dyskinesia in Parkinson's disease.

BACKGROUND: Dopamine replacement therapy is an established treatment for motor symptoms of Parkinson's disease, but its long-term use is often limited by the eventual development of motor complications, including levodopa-induced dyskinesia. Genetic background, particularly polymorphisms of dopamine metabolism genes, may affect the occurrence of dyskinesia in Parkinson's disease patients. METHODS: We investigated polymorphisms of dopamine metabolism genes, including catechol-O-methyltransferase, monoamine oxidase B, dopamine beta-hydroxylasedopamine, dopamine receptors D1, D2, and D3, and dopamine transporter, in 110 patients with Parkinson's disease. Cox proportional hazards regression was used to detect associations between genotypes and levodopa-induced dyskinesia. RESULTS: Monoamine oxidase B rs1799836 was the only polymorphism correlated with risk of dyskinesia. Patients with an AG or GG genotype were more likely to have dyskinesia than those with an AA genotype (adjusted hazard ratio, 3.41; 95% confidence interval, 1.28-9.10). Also, Kaplan-Meier curves demonstrated that patients with an AG or GG genotype developed dyskinesia earlier than those with an AA genotype (log-rank test, p = .004). CONCLUSIONS: In Parkinson's disease patients, the monoamine oxidase B rs1799836 G allele is associated with a greater likelihood of developing dyskinesia than the A allele, possibly due to its association with lower monoamine oxidase B activity in the brain. Thus, detection of monoamine oxidase B polymorphisms may be useful for determining the optimal dosing of antiparkinson medications.

Temporal expression profiling of DAMPs-related genes revealed the biphasic post-ischemic inflammation in the experimental stroke model.

The neuroinflammation in the ischemic brain could occur as sterile inflammation in response to damage-associated molecular patterns (DAMPs). However, its long-term dynamic transcriptional changes remain poorly understood. It is also unknown whether this neuroinflammation contributes to the recovery or just deteriorates the outcome. The purpose of this study is to characterize the temporal transcriptional changes in the post-stroke brain focusing on DAMPs-related genes by RNA-sequencing during the period of 28 days. We conducted the RNA-sequencing on day 1, 3, 7, 14, 28 post-stroke in the mouse photothrombosis model. The gross morphological observation showed the ischemic lesion on the ipsilateral cortex turned into a scar with the clearance of cellular debris by day 28. The transcriptome analyses indicated that post-stroke period of 28 days was classified into four categories (I Baseline, II Acute, III Sub-acute-#1, IV Sub-acute-#2 phase). During this period, the well-known genes for DAMPs, receptors, downstream cascades, pro-inflammatory cytokines, and phagocytosis were transcriptionally increased. The gene ontology (GO) analysis of biological process indicated that differentially expressed genes (DEGs) are genetically programmed to achieve immune and inflammatory pathways. Interestingly, we found the biphasic induction of various genes, including DAMPs and pro-inflammatory factors, peaking at acute and sub-acute phases. At the sub-acute phase, we also observed the induction of genes for phagocytosis as well as regulatory and growth factors. Further, we found the activation of CREB (cAMP-response element binding protein), one of the key players for neuronal plasticity, in peri-ischemic neurons by immunohistochemistry at this phase. Taken together, these findings raise the possibility the recurrent inflammation occurs at the sub-acute phase in the post-stroke brain, which could be involved in the debris clearance as well as neural reorganization.

Multiplex PCR and multicolor probes melting for the simultaneous detection of five UGT1A1 variants.

The multiplex PCR melting analysis method was developed for detecting the five UGT1A1 variants. Multiplexing was achieved using color probes and Tm. The probes for *28/*6, *27, *29, and *7 were discriminated by colors. Although the probes for *28 and *6 had the same colors, their variants were clearly discriminated by probe Tm. The allelic frequencies of each genotype were 0.12 for *28, 0.19 for *6, 0.02 for *27, 0.0 for *29, and 0.005 for *7. We developed a multiplex PCR melting analysis method, which will be useful in molecular diagnostics and pharmacogenetic analyses in clinical laboratories.

Evaluation of analytical factors associated with targeted MEFV gene sequencing using long-range PCR/massively parallel sequencing of whole blood DNA for molecular diagnosis of Familial Mediterranean fever.

BACKGROUND: Long-range PCR (LR-PCR) is used to enrich the target regions of the genome. This study aimed to establish the pipeline of targeted gene sequencing using LR-PCR and massively parallel sequencing (MPS). METHODS: The 14-kb-long MEFV gene, including the entire coding exons, was selected as a target gene and amplified using LR-PCR. The evaluated analytical factors were as follows: LR-PCR conditions, three types of post-PCR cleanup methods, and two types of MPS library preparation methods. RESULTS: With regard to LR-PCR conditions, Tks Gflex DNA polymerase at 7-min (30-s/kb) annealing/extension with 100-ng genomic DNA input had the highest yield. Regarding post-PCR purification methods, the magnetic beads-based method had high recovery and purity. In the MPS library preparation methods, the ligation-based method had a higher base coverage in the target (94.58%), uniformity of base coverage (99.95%), and target bases with no strand bias (97.40%). The exonic variants determined by Sanger sequencing were detected by both ligation- and transposon-based methods. CONCLUSIONS: Various analytical factors were evaluated, and the pipeline of targeted gene sequencing using LR-PCR and MPS was established. These data can enable the optimization of targeted gene sequencing using LR-PCR and MPS in the clinical laboratory.