Alterations in driving ability and their relationship with morphometric magnetic resonance imaging indicators in patients with amnestic mild cognitive impairment and Alzheimer's disease.

BACKGROUND: Drivers with dementia are at a higher risk of motor vehicle accidents. The characteristics of driving behaviour of patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD) have not been fully elucidated. We investigated driving ability and its relationship with cognitive function and magnetic resonance imaging (MRI) morphometry indicators. METHODS: The driving abilities of 19 patients with AD and 11 with amnestic MCI (aMCI) were evaluated using a driving simulator. The association between each driving ability parameter and the Mini-Mental State Examination (MMSE) score or voxel-based specific regional analysis system for AD (VSRAD) was assessed. RESULTS: Patients with AD made a significantly higher number of operational errors than those with aMCI in attention allocation in the complex task test (P = 0.0008). The number of operational errors in attention allocation in the complex task test significantly and negatively correlated with MMSE scores in all participants (r = -0.4354, P = 0.0162). The decision time in the selective reaction test significantly and positively correlated with the severity and extent of medial temporal structural atrophy (r = 0.4807, P = 0.0372; r = 0.4862, P = 0.0348; respectively). CONCLUSION: An increase in the operational errors for attention allocation in the complex task test could be a potential indicator of progression from aMCI to AD. Atrophy of the medial temporal structures could be a potential predictor of impaired judgement in driving performance in aMCI and AD. A driving simulator could be useful for evaluating the driving abilities of individuals with aMCI and AD.

Endothelial expression of human amyloid precursor protein leads to amyloid ß in the blood and induces cerebral amyloid angiopathy in knock-in mice.

The deposition of amyloid ß (Aß) in blood vessels of the brain, known as cerebral amyloid angiopathy (CAA), is observed in most patients with Alzheimer's disease (AD). Compared with the pathology of CAA in humans, the pathology in most mouse models of AD is not as evident, making it difficult to examine the contribution of CAA to the pathogenesis of AD. On the basis of biochemical analyses that showed blood levels of soluble amyloid precursor protein (APP) in rats and mice were markedly lower than those measured in human samples, we hypothesized that endothelial APP expression would be markedly lower in rodents and subsequently generated mice that specifically express human WT APP (APP770) in endothelial cells (ECs). The resulting EC-APP770+ mice exhibited increased levels of serum Aß and soluble APP, indicating that endothelial APP makes a critical contribution to blood Aß levels. Even though aged EC-APP770+ mice did not exhibit Aß deposition in the cortical blood vessels, crossing these animals with APP knock-in mice (AppNL-F/NL-F) led to an expanded CAA pathology, as evidenced by increased amounts of amyloid accumulated in the cortical blood vessels. These results highlight an overlooked interplay between neuronal and endothelial APP in brain vascular Aß deposition. We propose that these EC-APP770+:AppNL-F/NL-F mice may be useful to study the basic molecular mechanisms behind the possible breakdown of the blood-brain barrier upon administration of anti-Aß antibodies.

Relationship between Neurological Deterioration and Blood Pressure/Heart Rate Variability in Patients with Acute Cerebral Infarction.

OBJECTIVES: Neurological deterioration (ND) during hospitalization is an independent predictor of poor prognosis after stroke. Risk factors affecting early ND within 48 h post stroke have been intensively investigated, while few data are available on those for late ND after transfer to a wheelchair. Therefore, it was investigated whether hemodynamic factors may affect the late ND during hospitalization. MATERIALS AND METHODS: A retrospective study was conducted on 135 patients with atherothrombotic or cardiogenic cerebral infarction who were admitted to our hospital between April 1st, 2014 and July 31st, 2017. During hospitalization, average, maximum, and minimum values were determined for systolic blood pressure (sBP), diastolic BP (dBP), and heart rate (HR), respectively.135 patients were classified into two groups; ND (+) group, in which modified Barthel index score at the time of transfer to a wheelchair showed five points or more decrease between wheelchair transfer and discharge, and ND (-) group, which did not. Vital indices were compared between the two groups and subjected to ROC-curve analysis. RESULTS: The ND (+) group included 32 patients, and the ND (-) 103. Significant differences were found between the groups in four items; sBPmin (p = 0.029), dBPmin (p = 0.019), HRave (p = 0.028), and HRmax (p < 0.01). The ND (+) group showed lower sBPmin and dBPmin, and higher HRave and HRmax than the ND (-) group. CONCLUSIONS: Late ND after transfer to a wheelchair is related to the vital indices during hospitalization and should be cautiously managed to prevent late ND.

High Mobility Group A1 Regulates Transcription Levels of Oligodendrocyte Marker Genes in Cultured Oligodendrocyte Precursor Cells.

Oligodendrocyte precursor cells (OPCs) serve as progenitor cells of terminally differentiated oligodendrocytes. Past studies have confirmed the importance of epigenetic system in OPC differentiation to oligodendrocytes. High mobility group A1 (HMGA1) is a small non-histone nuclear protein that binds DNA and modifies the chromatin conformational state. However, it is still completely unknown about the roles of HMGA1 in the process of OPC differentiation. In this study, we prepared primary OPC cultures from the neonatal rat cortex and examined whether the loss- and gain-of-function of HMGA1 would change the mRNA levels of oligodendrocyte markers, such as Cnp, Mbp, Myrf and Plp during the process of OPC differentiation. In our system, the mRNA levels of Cnp, Mbp, Myrf and Plp increased depending on the oligodendrocyte maturation step, but the level of Hmga1 mRNA decreased. When HMGA1 was knocked down by a siRNA approach, the mRNA levels of Cnp, Mbp, Myrf and Plp were smaller in OPCs with Hmga1 siRNA compared to the ones in the control OPCs. On the contrary, when HMGA1 expression was increased by transfection of the Hmga1 plasmid, the mRNA levels of Cnp, Mbp, Myrf and Plp were slightly larger compared to the ones in the control OPCs. These data may suggest that HMGA1 participates in the process of OPC differentiation by regulating the mRNA expression level of myelin-related genes.

Association between cortical microinfarcts and total small vessel disease burden in cerebral amyloid angiopathy on 3-Tesla magnetic resonance imaging.

BACKGROUND AND PURPOSE: Cortical microinfarcts (CMIs) are frequently found in the brains of patients with advanced cerebral amyloid angiopathy (CAA) at autopsy. The small vessel disease (SVD) score for CAA (i.e., the CAA-SVD score) has been proposed to evaluate the severity of CAA-associated vasculopathic changes by a combination of magnetic resonance imaging (MRI) markers. The aim of this study was to examine the association between total CAA-SVD score and features of CMIs on in vivo 3-Tesla MRI. METHODS: Eighty patients with probable CAA were retrospectively analyzed. Lobar cerebral microbleeds, cortical superficial siderosis, enlargement of perivascular space in the centrum semiovale and white matter hyperintensity were collectively assessed, and the total CAA-SVD score was calculated. The presence of CMI was also examined. RESULTS: Of the 80 patients, 13 (16.25%) had CMIs. CMIs were detected more frequently in the parietal and occipital lobes. A positive correlation was found between total CAA-SVD score and prevalence of CMI (ρ = 0.943; p = 0.005). Total CAA-SVD score was significantly higher in patients with CMIs than in those without (p = 0.009). In a multivariable logistic regression analysis, the presence of CMIs was significantly associated with total CAA-SVD score (odds ratio 2.318 [95% confidence interval 1.228-4.376]; p = 0.01, per each additional point). CONCLUSIONS: The presence of CMIs with a high CAA-SVD score could be an indicator of more severe amyloid-associated vasculopathic changes in patients with probable CAA.

Long-term MRI changes in a patient with Kelch-like protein 11-associated paraneoplastic neurological syndrome.

BACKGROUND AND PURPOSE: The aim of this study was to identify the long-term radiological changes, autoantibody specificities, and clinical course in a patient with kelch-like protein 11 (KLHL11)-associated paraneoplastic neurological syndrome (PNS). METHODS: Serial brain magnetic resonance images were retrospectively assessed. To test for KLHL11 autoantibodies, longitudinal cerebrospinal fluid (CSF) and serum samples were screened by Phage-display ImmunoPrecipitation and Sequencing (PhIP-Seq). Immunohistochemistry was also performed to assess for the presence of KLHL11 in the patient's seminoma tissue. RESULTS: A 42-year-old man presented with progressive ataxia and sensorineural hearing loss. Metastatic seminoma was detected 11 months after the onset of the neurological symptoms. Although immunotherapy was partially effective, his cerebellar ataxia gradually worsened over the next 8 years. Brain magnetic resonance imaging revealed progressive brainstem and cerebellar atrophy with a "hot-cross-bun sign", and low-signal intensity on susceptibility-weighted imaging (SWI) in the substantia nigra, red nucleus and dentate nuclei. PhIP-Seq enriched for KLHL11-derived peptides in all samples. Immunohistochemical staining of mouse brain with the patient CSF showed co-localization with a KLHL11 commercial antibody in the medulla and dentate nucleus. Immunohistochemical analysis of seminoma tissue showed anti-KLHL11 antibody-positive particles in cytoplasm. CONCLUSIONS: This study suggests that KLHL11-PNS should be included in the differential diagnosis for patients with brainstem and cerebellar atrophy and signal changes not only on T2-FLAIR but also on SWI, which might otherwise be interpreted as secondary to a neurodegenerative disease such as multiple system atrophy.

Miller Fisher syndrome following BNT162b2 mRNA coronavirus 2019 vaccination.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began in late 2019. One of the vaccines approved against COVID-19 is the BNT162b2 mRNA COVID-19 vaccine (Pfizer/BioNTech). CASE PRESENTATION: We present the case of a 71-year-old man with no history of the SARS-CoV-2 infection or any recent viral or bacterial illnesses who presented with bilateral oculomotor palsy and limb ataxia after BNT162b2 mRNA COVID-19 vaccination. The diagnosis of Miller Fisher syndrome (MFS) was established based on physical examination, brain magnetic resonance imaging (MRI), cerebrospinal fluid analysis (CSF), and positron emission tomography (PET). There was no evidence of other predisposing infectious or autoimmune factors, and the period from COVID-19 vaccination to the appearance of neurological symptoms was similar to that of other vaccines and preceding events, such as infection. CONCLUSION: Guillain-Barré syndrome (GBS) and its variants after COVID-19 vaccination are extremely rare. Note that more research is needed to establish an association between MFS and COVID-19 vaccines. In our opinion, the benefits of COVID-19 vaccination largely outweigh its risks.

Cortical Microinfarcts Detected by 3-Tesla Magnetic Resonance Imaging: Differentiation Between Cerebral Amyloid Angiopathy and Embolism.

Background and Purpose- Cortical microinfarcts (CMIs) are small ischemic lesions found in cerebral amyloid angiopathy (CAA) and embolic stroke. This study aimed to differentiate CMIs caused by CAA from those caused by microembolisms, using 3-Tesla magnetic resonance imaging. Methods- We retrospectively investigated 70 patients with at least 1 cortical infarct <10 mm on 3-dimensional double inversion recovery imaging. Of the 70 patients, 43 had an embolic stroke history (Emboli-G) while 27 had CAA-group. We compared the size, number, location, and distribution of CMIs between groups and designed a radiological score for differentiation based on the comparisons. Results- CAA-group showed significantly more lesions <5 mm, which were restricted to the cortex (P<0.01). Cortical lesion number was significantly higher in Emboli-G than in CAA-group (4 versus 2; P<0.01). Lesions in CAA-group and Emboli-G were disproportionately located in the occipital lobe (P<0.01) and frontal or parietal lobe (P=0.04), respectively. In radiological scoring, ≥3 points strongly predicted microembolism (sensitivity, 63%; specificity, 92%) or CAA (sensitivity, 63%; specificity, 91%). The areas under the receiver operating characteristic curve were 0.85 and 0.87 for microembolism and CAA, respectively. Conclusions- Characteristics of CMIs on 3T-magnetic resonance imaging may differentiate CMIs due to CAA from those due to microembolisms.

Myasthenia gravis with anti-muscle-specific tyrosine kinase antibodies during therapy for multiple myeloma: a case report.

BACKGROUND: The onset of myasthenia (MG) gravis with anti-muscle-specific tyrosine kinase (MuSK) antibodies most commonly peaks in the fourth decade of life, and MG with MuSK antibodies (MuSK-MG) rarely coexists with a malignant tumor. To date, MuSK-MG has not been reported in multiple myeloma (MM). CASE PRESENTATION: A 60-year-old male with MM who was receiving treatment with bortezomib and thalidomide presented diplopia, ptosis, and limb weakness. A diagnosis of MM with Bence-Jones proteinuria was established when he was 56 years old, and he received chemotherapy with four courses of bortezomib and dexamethasone. Although he received thalidomide as maintenance therapy, it was discontinued a year before hospital admission because of sensory neuropathy as a side effect. Six months before hospital admission, he developed mild diplopia. One month before admission, his chemotherapy was interrupted because of viral infection and fatigability. Then he developed neck weakness and bilateral ptosis. A diagnosis of MuSK-MG was made based on neurological and serological examinations. According to the previous relevant literature, this is the first report of MuSK-MG in a patient with MM. CONCLUSIONS: In patients with MM, the possibility of co-existing of autoimmune disease, including MuSK-MG, should be considered. This case emphasizes the need to still consider testing for anti-MuSK antibodies in older MM patients where there is clinical suspicion for possible MG despite negative anti-acetylcholine receptor antibodies and lacking classic MuSK MG phenotype at onset.

Invasive Salmonella Enteritidis infection complicated by bacterial meningitis and vertebral osteomyelitis shortly after influenza A infection in an immunocompetent young adult.

Non-typhoidal Salmonella usually manifests as a self-limited acute gastroenteritis but may also cause severe invasive infections almost exclusively among children or immunosuppressed patients. A previously healthy 22-year-old man developed high fever with coma, multiple organ failure and shock. He had visited another hospital complaining of fever 2 days previously and was diagnosed with a common cold. No obvious site of infection was identified by radiology and a rapid test for influenza A virus was positive, indicating possible influenza-associated encephalopathy. However, blood as well as CSF culture yielded Salmonella enterica serotype Enteritidis. Therefore, the patient was considered to be suffering from bacterial meningitis with septic shock concomitant with influenza infection. Antiviral drugs and therapy for septic shock were initiated. He stabilized relatively quickly and his mental status dramatically improved. The patient denied preceding gastrointestinal symptoms, but mentioned that he received positive fecal Salmonella species culture results without medical intervention about 3 months previously. His laboratory values showed marked improvement but his elevated inflammatory markers and fever were sustained. On the 17th day of hospitalization, he complained of back pain and MRI showed lumbar vertebral osteomyelitis. This case indicates that (i) invasive Salmonella infection can be developed even in previously healthy adults; (ii) chronic carriage of Salmonella is a predisposing factor to development of invasive infections, and influenza infection may contribute to such "breakthrough infections"; (iii) attention to manifestation of metastatic extra-intestinal foci even after resolution of sepsis is necessary.

Differential roles of epigenetic regulators in the survival and differentiation of oligodendrocyte precursor cells.

During development or after brain injury, oligodendrocyte precursor cells (OPCs) differentiate into oligodendrocytes to supplement the number of oligodendrocytes. Although mechanisms of OPC differentiation have been extensively examined, the role of epigenetic regulators, such as histone deacetylases (HDACs) and DNA methyltransferase enzymes (DNMTs), in this process is still mostly unknown. Here, we report the differential roles of epigenetic regulators in OPC differentiation. We prepared primary OPC cultures from neonatal rat cortex. Our cultured OPCs expressed substantial amounts of mRNA for HDAC1, HDAC2, DNMT1, and DNMT3a. mRNA levels of HDAC1 and HDAC2 were both decreased by the time OPCs differentiated into myelin-basic-protein expressing oligodendrocytes. However, DNMT1 or DNMT3a mRNA level gradually decreased or increased during the differentiation step, respectively. We then knocked down those regulators in cultured OPCs with siRNA technique before starting OPC differentiation. While HDAC1 knockdown suppressed OPC differentiation, HDAC2 knockdown promoted OPC differentiation. DNMT1 knockdown also suppressed OPC differentiation, but unlike HDAC1/2, DNMT1-deficient cells showed cell damage during the later phase of OPC differentiation. On the other hand, when OPCs were transfected with siRNA for DNMT3a, the number of OPCs was decreased, indicating that DNMT3a may participate in OPC survival/proliferation. Taken together, these data demonstrate that each epigenetic regulator has different phase-specific roles in OPC survival and differentiation.

A-Kinase Anchor Protein 12 Is Required for Oligodendrocyte Differentiation in Adult White Matter.

Oligodendrocyte precursor cells (OPCs) give rise to oligodendrocytes in cerebral white matter. However, the underlying mechanisms that regulate this process remain to be fully defined, especially in adult brains. Recently, it has been suggested that signaling via A-kinase anchor protein 12 (AKAP12), a scaffolding protein that associates with intracellular molecules such as protein kinase A, may be involved in Schwann cell homeostasis and peripheral myelination. Here, we asked whether AKAP12 also regulates the mechanisms of myelination in the CNS. AKAP12 knockout mice were compared against wild-type (WT) mice in a series of neurochemical and behavioral assays. Compared with WTs, 2-months old AKAP12 knockout mice exhibited loss of myelin in white matter of the corpus callosum, along with perturbations in working memory as measured by a standard Y-maze test. Unexpectedly, very few OPCs expressed AKAP12 in the corpus callosum region. Instead, pericytes appeared to be one of the major AKAP12-expressing cells. In a cell culture model system, conditioned culture media from normal pericytes promoted in-vitro OPC maturation. However, conditioned media from AKAP12-deficient pericytes did not support the OPC function. These findings suggest that AKAP12 signaling in pericytes may be required for OPC-to-oligodendrocyte renewal to maintain the white matter homeostasis in adult brain. Stem Cells 2018;36:751-760.

Small Cortical Infarcts Transformed to Lobar Cerebral Microbleeds: A Case Series.

Cerebral microbleeds (MBs) have been often observed due to the development of imaging devices, and are classified to deep and lobar MBs. Lobar MBs are strongly associated with cerebral amyloid angiopathy. Here, we report 3 cases of lobar MBs that developed after small cortical ischemic stroke. One case underwent carotid artery stenting for severe carotid stenosis, one was diagnosed with artery-to-artery embolism, and the other was embolic stroke of undetermined source. New small cortical infarctions were detected with diffusion-weighted magnetic resonance imaging (MRI). Initial MRI revealed no hemorrhage around the ischemic lesion on T2*-weighted gradient-recalled echo or susceptibility-weighted imaging (SWI) at the onset of stroke. Follow-up SWI after 12-20 months revealed lobar MBs in the previously detected ischemic lesions, and high-intensity lesions remained around the MBs on fluid-attenuated inversion recovery imaging. These cases revealed that cerebral MBs developed through the transformation of small cortical infarctions. All cases showed lobar MBs, and these MBs existed in the previously detected ischemic lesions at a chronic stage. Lobar MBs present around ischemic lesions may predict embolic infarcts.

Comparison of Premortem Magnetic Resonance Imaging and Postmortem Autopsy Findings of a Cortical Microinfarct.

An 85-year-old woman diagnosed with amyotrophic lateral sclerosis died of pneumonia and was autopsied. Magnetic resonance imaging (MRI) performed 16 days before death revealed an intracortical high-intensity lesion in her right temporal cortex on three-dimensional (3D)-double inversion recovery (DIR) and 3D-fluid-attenuated inversion recovery (FLAIR) images. Histopathological examination indicated a cortical microinfarct (CMI) juxtaposed to cerebral amyloid angiopathy. Recently, in vivo detection of CMIs using 3D-DIR and 3D-FLAIR on 3-tesla MRI has been reported, and postmortem MRI study confirmed the presence of CMIs. This is the first case study to compare CMI findings detected upon premortem MRI to the CMI itself discovered upon postmortem neuropathological examination.

Complement Activation in Capillary Cerebral Amyloid Angiopathy.

BACKGROUND: Cerebral amyloid angiopathy (CAA) is classified as type 1 with capillary amyloid ß (Aß) or type 2 without capillary Aß. While it is known that CAA activates complement, an inflammatory mediator, there is no information on the relationship between capillary Aß and complement activation. METHODS: We evaluated 34 autopsy brains, including 22 with CAA and 12 with other neurodegenerative diseases. We assessed the vascular density of CAA by analyzing the expression of complement (C1q, C3d, C6, C5b-9), macrophage scavenger receptor (MSR), and apolipoprotein E (ApoE). RESULTS: Capillary immunostaining for C1q, C3d, MSR, and ApoE was identified almost exclusively in CAA-type1 brains. There was intense expression of C1q, C3d, MSR, and ApoE, as well as weaker expression of C5b-9 and C6 in the arteries/ arterioles of both CAA subtypes, but not in control brains. C5b-9 and C6 were preferentially expressed in arteries/arterioles with subcortical hemorrhage or cortical superficial siderosis. Triple immunofluorescence revealed that C1q, C3d, and ApoE were colocalized with Aß in CAA brain capillaries. CONCLUSION: Complement, MSR, and ApoE were only coexpressed in the presence of Aß accumulation in capillaries, suggesting a role for complement activation in the propagation of Aß. Additionally, C5b-9 expression may be associated with hemorrhagic brain injury in CAA.

Astrocytes Promote Oligodendrogenesis after White Matter Damage via Brain-Derived Neurotrophic Factor.

Oligodendrocyte precursor cells (OPCs) in the adult brain contribute to white matter homeostasis. After white matter damage, OPCs compensate for oligodendrocyte loss by differentiating into mature oligodendrocytes. However, the underlying mechanisms remain to be fully defined. Here, we test the hypothesis that, during endogenous recovery from white matter ischemic injury, astrocytes support the maturation of OPCs by secreting brain-derived neurotrophic factor (BDNF). For in vitro experiments, cultured primary OPCs and astrocytes were prepared from postnatal day 2 rat cortex. When OPCs were subjected to chemical hypoxic stress by exposing them to sublethal CoCl2 for 7 d, in vitro OPC differentiation into oligodendrocytes was significantly suppressed. Conditioned medium from astrocytes (astro-medium) restored the process of OPC maturation even under the stressed conditions. When astro-medium was filtered with TrkB-Fc to remove BDNF, the BDNF-deficient astro-medium no longer supported OPC maturation. For in vivo experiments, we analyzed a transgenic mouse line (GFAP(cre)/BDNF(wt/fl)) in which BDNF expression is downregulated specifically in GFAP(+) astrocytes. Both wild-type (GFAP(wt)/BDNF(wt/fl) mice) and transgenic mice were subjected to prolonged cerebral hypoperfusion by bilateral common carotid artery stenosis. As expected, compared with wild-type mice, the transgenic mice exhibited a lower number of newly generated oligodendrocytes and larger white matter damage. Together, these findings demonstrate that, during endogenous recovery from white matter damage, astrocytes may promote oligodendrogenesis by secreting BDNF. SIGNIFICANCE STATEMENT: The repair of white matter after brain injury and neurodegeneration remains a tremendous hurdle for a wide spectrum of CNS disorders. One potentially important opportunity may reside in the response of residual oligodendrocyte precursor cells (OPCs). OPCs may serve as a back-up for generating mature oligodendrocytes in damaged white matter. However, the underlying mechanisms are still mostly unknown. Here, we use a combination of cell biology and an animal model to report a new pathway in which astrocyte-derived BDNF supports oligodendrogenesis and regeneration after white matter damage. These findings provide new mechanistic insight into white matter physiology and pathophysiology, which would be broadly and clinically applicable to CNS disease.

Astrocyte-Derived Pentraxin 3 Supports Blood-Brain Barrier Integrity Under Acute Phase of Stroke.

BACKGROUND AND PURPOSE: Pentraxin 3 (PTX3) is released on inflammatory responses in many organs. However, roles of PTX3 in brain are still mostly unknown. Here we asked whether and how PTX3 contributes to blood-brain barrier dysfunction during the acute phase of ischemic stroke. METHODS: In vivo, spontaneously hypertensive rats were subjected to focal cerebral ischemia by transient middle cerebral artery occlusion. At day 3, brains were analyzed to evaluate the cellular origin of PTX3 expression. Correlations with blood-brain barrier breakdown were assessed by IgG staining. In vitro, rat primary astrocytes and rat brain endothelial RBE.4 cells were cultured to study the role of astrocyte-derived PTX3 on vascular endothelial growth factor-mediated endothelial permeability. RESULTS: During the acute phase of stroke, reactive astrocytes in the peri-infarct area expressed PTX3. There was negative correlation between gradients of IgG leakage and PTX3-positive astrocytes. Cell culture experiments showed that astrocyte-conditioned media increased levels of tight junction proteins and reduced endothelial permeability under normal conditions. Removing PTX3 from astrocyte-conditioned media by immunoprecipitation increased endothelial permeability. PTX3 strongly bound vascular endothelial growth factor in vitro and was able to decrease vascular endothelial growth factor-induced endothelial permeability. CONCLUSIONS: Astrocytes in peri-infarct areas upregulate PTX3, which may support blood-brain barrier integrity by regulating vascular endothelial growth factor-related mechanisms. This response in astrocytes may comprise a compensatory mechanism for maintaining blood-brain barrier function after ischemic stroke.

Neuropsychological study of amyotrophic lateral sclerosis and parkinsonism-dementia complex in Kii peninsula, Japan.

BACKGROUND: The Kii peninsula of Japan is one of the foci of amyotrophic lateral sclerosis and parkinsonism-dementia complex (ALS/PDC) in the world. The purpose of this study is to clarify the neuropsychological features of the patients with ALS/PDC of the Kii peninsula (Kii ALS/PDC). METHODS: The medical interview was done on 13 patients with Kii ALS/PDC, 12 patients with Alzheimer's disease, 10 patients with progressive supranuclear palsy, 10 patients with frontotemporal lobar degeneration and 10 patients with dementia with Lewy bodies. These patients and their carer/spouse were asked to report any history of abulia-apathy, hallucination, personality change and other variety of symptoms. Patients also underwent brain magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), and neuropsychological tests comprising the Mini Mental State Examination, Raven's Colored Progressive Matrices, verbal fluency, and Paired-Associate Word Learning Test and some of them were assessed with the Frontal Assessment Battery (FAB). RESULTS: All patients with Kii ALS/PDC had cognitive dysfunction including abulia-apathy, bradyphrenia, hallucination, decrease of extraversion, disorientation, and delayed reaction time. Brain MRI showed atrophy of the frontal and/or temporal lobes, and SPECT revealed a decrease in cerebral blood flow of the frontal and/or temporal lobes in all patients with Kii ALS/PDC. Disorientation, difficulty in word recall, delayed reaction time, and low FAB score were recognized in Kii ALS/PDC patients with cognitive dysfunction. CONCLUSIONS: The core neuropsychological features of the patients with Kii ALS/PDC were characterized by marked abulia-apathy, bradyphrenia, and hallucination.

Internal carotid artery dissection in a patient with Parkinson's disease after COVID-19 infection.

Background: Internal carotid artery (ICA) dissection is a relatively rare cause of acute ischemic stroke. Stretching and compression of ICA due to sudden acceleration, deceleration, and rotational forces are risk factors for ICA dissection. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is believed to trigger an inflammatory response that exacerbates endothelial dysfunction and leads to arterial dissection. Although levodopa-induced cervical dyskinesia in Parkinson's disease often manifests as choreiform movement, dissection has not been reported in such patients. Case presentation: A 51-year-old man with Parkinson's disease (PD) presented with gradually worsening neck pain and transient aphasia 1 week after mild coronavirus disease 2019 (COVID-19) infection. The patient already had neck pain due to cervical spondylosis and presented with levodopa-induced cervical dyskinesia. Magnetic resonance imaging revealed acute ischemic stroke in the left parietal lobe and an intramural hematoma with an area of stenosis in the left ICA. The patient was diagnosed with left ICA dissection. Conclusions: COVID-19 infection can cause vessel wall vulnerability. Although patients with PD often have neck pain, ICA dissection should be considered a differential diagnosis if the patient has a recent history of COVID-19.