Makoto Eriguchi

Brain Microbleeds and Global Cognitive Function in Adults Without Neurological Disorder

Background and Purpose— Increasing attention has been paid to associations between cognitive dysfunction and brain microbleeds (MBs). Because all previous studies have investigated patients with neurological disorders, we examined subjects without neurological disorder in order to clarify pathogenic relationships. Methods— A total of 518 consecutive adults without neurological disorder who had undergone health-screening tests of the brain were studied prospectively. Gradient-echo T2*-weighted MRI using a 1.5-T system was used to detect MBs. The Mini-Mental State Examination (MMSE) was administered to determine cognitive functions. MMSE scores <27 or >1.5 SDs below the age-related mean were regarded as subnormal. Results— MBs were found in 35 subjects (6.8%). MMSE score <27 was found in 25 subjects (4.8%), with MMSE score >1.5 SDs below the age-related mean in 34 subjects (6.6%). Univariate analysis showed presence and number of MBs, short duration of education, and severe white matter hyperintensities as significantly associated with subnormal scores. In logistic regression analysis, presence of MBs (odds ratio [OR], 5.44; 95% CI, 1.83 to 16.19) and number of MBs (OR, 1.32; 95% CI, 1.04 to 1.68) still displayed significant associations with MMSE score <27. Logistic regression analysis revealed a significant relationship between presence (OR, 3.93; 95% CI, 1.44 to 10.74) and number (OR, 1.26; 95% CI, 1.01 to 1.59) of MBs and MMSE score >1.5 SDs below the age-related mean. Among MMSE subscores, “attention and calculation” was significantly lower in MB-positive subjects (P=0.017). Conclusions— MBs appear to be primarily associated with global cognitive dysfunction.

Distributional Impact of Brain Microbleeds on Global Cognitive Function in Adults Without Neurological Disorder

Background and Purpose— Brain microbleeds (MBs) are considered to be associated with cognitive decline and can be pathologically and topographically classified as cerebral amyloid angiopathy-related (located in lobar regions) and hypertensive microangiopathy-related (located in deep regions). We examined whether different effects on global cognitive function might be seen with different distributions of MBs. Methods— A total of 1279 adults without neurological disorders were studied prospectively. Subjects were divided into 4 groups: without-MBs group; lobar group; deep group; and with in both areas (diffuse group). The Mini-Mental State Examination was administered to determine global cognitive functions, with scores <27 regarded as subnormal. Results— MBs were detected in 98 subjects (8%): 36 subjects (3%) classified as lobar group, 48 subjects (4%) as deep group, and 14 subjects (1%) as diffuse group. Subnormal scores were found in 76 subjects (5.9%), associated with age, education, hypertension, severe white matter hyperintensities, and distribution and number of MBs. In the final model of logistic regression analysis, the deep group (OR, 2.79; 95% CI, 1.14–6.79) was associated with subnormal scores, whereas the lobar group (OR, 0.77; 95% CI, 0.17–3.44) was not. Trend for the diffuse group did not reach the level of significance (OR, 5.01; 95% CI, 0.88–28.41). These trends were also seen in analysis using another cut-off point for subnormal score. Scores for total Mini-Mental State Examination and attention and calculation were significantly lower in the deep group and the diffuse groups compared with the without-MBs group. Conclusions— This Japanese cross-sectional study demonstrated that MB-related global cognitive dysfunction seems to occur based on hypertensive pathogenesis rather than on cerebral amyloid angiopathy.

Topography and associations of perivascular spaces in healthy adults The Kashima Scan Study

Objective: We investigated whether the topography of MRI-visible perivascular spaces (PVS) is associated with markers of specific underlying small vessel disease, including cerebral microbleed (CMB) distribution, in neurologically healthy adults. Methods: We analyzed baseline data of an ongoing Japanese population-based cohort study. PVS were rated in the basal ganglia (BG-PVS) and centrum semiovale (CSO-PVS) on axial T2-weighted MRI using a validated rating scale (score 0–4). BG-PVS degree was classified as low (score <2) or high (score ≥2). CSO-PVS degree was classified as low (score <3) or high (score ≥3). Independent demographic, clinical, and imaging factors for high degree of BG-PVS and CSO-PVS were investigated. Results: A total of 1,575 neurologically healthy adults were included (mean age 57.1 years, SD 9.7; 47% male). In multivariable analyses, high degree of BG-PVS (n = 212, 14%) was associated with deep or infratentorial CMBs (odds ratio [OR] 2.77, 95% confidence interval [CI] 1.62–4.74), a marker of hypertensive arteriopathy; by contrast, high degree of CSO-PVS (n = 357, 23%) was associated with strictly lobar CMBs (OR 2.49, 95% CI 1.35–4.61), which share risk factors with cerebral amyloid angiopathy. Both high degree of BG-PVS and CSO-PVS were associated with hypertension (OR 2.03, 95% CI 1.46–2.82 and OR 1.39, 95% CI 1.07–1.81, respectively), lacunes (OR 3.35, 95% CI 1.92–5.86; OR 1.83 95% CI 1.08–3.08), and severe white matter hyperintensities (OR 2.17, 95% CI 1.42–3.31; OR 1.35, 95% CI 0.93–1.96), but these associations were stronger for high degree of BG-PVS. Conclusions: In a neurologically healthy cohort, the associations of PVS differ according to their topography. PVS distribution may be useful for the early detection and classification of small vessel disease.

Is multiple sclerosis an autoimmune disease

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) with varied clinical presentations and heterogeneous histopathological features. The underlying immunological abnormalities in MS lead to various neurological and autoimmune manifestations. There is strong evidence that MS is, at least in part, an immune-mediated disease. There is less evidence that MS is a classical autoimmune disease, even though many authors state this in the description of the disease. We show the evidence that both supports and refutes the autoimmune hypothesis. In addition, we present an alternate hypothesis based on virus infection to explain the pathogenesis of MS.

Marked cerebral atrophy is correlated with kidney dysfunction in nondisabled adults.

The relationship between kidney dysfunction, such as chronic kidney disease (CKD), and brain morphology has attracted increasing attention, but the association between kidney dysfunction and cerebral atrophy has yet to be determined. The purpose of this study was to clarify the relationship between kidney function and a substantial degree of cerebral atrophy. A total of 610 consecutive Japanese adults without neurological disorders who had undergone health screening tests of the brain were studied prospectively. Magnetic resonance imaging was performed using a 1.5-T scanner. Using a computer-assisted processing system, the percentage of cerebrum atrophy (%Cerebrum atrophy) was calculated as an index of cerebral atrophy. Atrophy was defined as >2 s.d.s below the mean %Cerebrum atrophy. The glomerular filtration rate (GFR) was estimated using the revised equations for estimated GFR from serum creatinine in Japan. Kidney function variables included the GFR value and the prevalence of subjects with GFR <60 ml min−1 per 1.73 m2. Cerebral atrophy was found in 25 (4.1%) cases. Univariate analysis showed that age, male sex, hypertension, each kidney function variable, white matter hyperintensities and lacunae were associated with cerebral atrophy. On logistic regression analysis, GFR (odds ratio (OR), 0.64; 95% confidence interval (CI), 0.42–0.98) and GFR <60 ml min−1 per 1.73 m2 (OR, 5.93; 95% CI, 1.82–19.27) were significantly associated with cerebral atrophy. On sub-analysis, GFR <60 ml min−1 per 1.73 m2 was significantly associated with cortical atrophy (OR, 3.23; 95% CI, 1.15–9.11). Decreased GFR was significantly associated with cerebral atrophy, indicating that treatment of CKD may control age-related degenerative processes of the brain.

α Pix enhances mutant huntingtin aggregation

Huntingtons disease is caused by polyglutamine-expanded mutant huntingtin (muhtt), an aggregation-prone protein. We identified the Pak-interacting exchange factor (alpha Pix/Cool2) as a novel huntingtin (htt) interacting protein, after screening actin-cytoskeleton organization-related factors. Using immunoprecipitation experiments, we show that alpha Pix binds to both the N-terminal of wild-type htt (wthtt) and mutant htt (muthtt). Colocalization studies revealed that alpha Pix accumulates in muthtt aggregates. Deletion analysis suggested that the dbl homology (DH) and pleckstrin homology (PH) domains of alpha Pix are required for its interaction with htt. Overexpression of alpha Pix enhanced muthtt aggregation by inducing SDS-soluble muthtt-muthtt interactions. Conversely, knocking down alpha Pix attenuated muhtt aggregation. These findings suggest that alpha Pix plays an important role in muthtt aggregation.

Identification of a new homozygous frameshift insertion mutation in the SIL1 gene in 3 Japanese patients with Marinesco-Sjögren syndrome.

Marinesco-Sjögren syndrome (MSS) is an autosomal recessive multisystem disorder characterized by cerebellar ataxia, cataracts, progressive muscular weakness, and developmental and mental retardation. Recently, mutations in the SIL1 gene on chromosome 5q31 have been shown to be a cause of MSS. We sequenced the entire SIL1-coding region in 3 unrelated Japanese patients with classical MSS and identified a novel homozygous frameshift insertion mutation, 936_937insG, in exon 9 in all 3 patients.

3-Methylglutaconic aciduria type I causes leukoencephalopathy of adult onset

3-Methylglutaconic amino aciduria (MGA) is characterized by an increased urinary excretion of 3-methylclutaconic acid and 3-methylglutaric acid.1 Four distinct forms are currently recognized: type I (MGA1), 3-methylglutaconyl-CoA hydratase deficiency caused by mutations of the AUH gene1–7; type II, caused by mutations in the tafazzin gene; type III, occurring in a genetic isolate of Iraqi Jews (causative gene has been recently isolated); and type IV, a heterogeneous group. The symptoms usually appear in the first decade of life.1–7 We herein report MGA1 presenting with progressive leukoencephalopathy in late adulthood. A 55–year-old woman was referred to us for an evaluation of progressive forgetfulness and an unsteady gait since age 53. Urinary incontinence also appeared at age 52. She easily tripped and fell, resulting in a fracture of her right clavicle. Her parents were first cousins. She had no serious illnesses during her childhood, graduated from a junior college, got married at age 23, and gave birth to two healthy children. …

Immunopathological Significance of Ovarian Teratoma in Patients with Anti-N-Methyl-D-Aspartate Receptor Encephalitis

Background: The clinical importance of ovarian teratoma in anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis has been established, however investigations of ovarian teratoma in patients with anti-NMDAR encephalitis remain limited. Objective: To clarify differences in NMDAR distribution and lymphocyte infiltration in ovarian teratoma between patients with and without anti-NMDAR encephalitis. Methods: Participants initially comprised 26 patients with ovarian teratomas. NMDAR distribution and lymphocyte infiltration in ovarian teratomas were examined using immunopathological techniques. Clinical, laboratory, and radiological data were compared between patients showing the features of encephalitis. Anti-NMDAR antibodies in the serum and cerebrospinal fluid were also measured in encephalitis patients. Results: Neuronal tissues were obtained from ovarian teratomas in 22 patients (after excluding 4 patients who did not satisfy the inclusion criteria), and the presence of NMDA receptor subunits was revealed in all patients. Lymphocyte infiltration was more frequent in the encephalitis group (n = 3) than in the non-encephalitis group. In particular, dense B-lymphocyte infiltration near neural tissues was observed in the encephalitis group. Conclusions: Differences in lymphocyte infiltration in ovarian teratomas between anti-NMDAR encephalitis and non-encephalitis patients suggest the immunological importance of the ovarian teratoma as the site of antigen presentation in anti-NMDAR encephalitis.

Stroke Scale Items Associated with Neurologic Deterioration within 24 Hours after Recombinant Tissue Plasminogen Activator Therapy

It is unclear when and which neurologic deficits should be examined within 24 hours after intravenous recombinant tissue plasminogen activator (rt-PA) therapy for acute ischemic stroke. Relationships between serial changes in National Institutes of Health Stroke Scale (NIHSS) subscores and neurologic deterioration (ND) within the first 24 hours after therapy were investigated in 43 consecutive patients. The NIHSS score was measured by neurologists 28 times within 24 hours after therapy. Assessments of subscores associated with ND, defined as the first change 4 or more points from baseline, were performed at 15 minutes (most frequent time of the first ND), 120 minutes (median time of the first ND), and 24 hours after therapy. Seventeen of 43 patients (age range, 55-94 years) showed ND. Of the NIHSS subscores, increases in scores for loss of consciousness (15 minutes, P = .001; 120 minutes, P = .026; 24 hours, P = .018) and motor limbs total (15 minutes, P = .014; 120 minutes, P = .031) were related to deterioration. Items such as questions, gaze, visual fields, ataxia, language, dysarthria, and extinction/inattention were not related to deterioration at any time. In conclusion, ND of ischemic stroke patients treated with intravenous rt-PA therapy was frequently seen within 120 minutes after therapy. Items such as loss of consciousness and motor limbs total may be considered indices for monitoring neurologic deficits after therapy.