Recombinant parechovirus A3 possibly causes various clinical manifestations, including myalgia; findings in Yamagata, Japan in 2019.

BACKGROUND: Parechovirus A3 was first reported in 2004 and has been recognized as a causative agent of mild and severe infections in children. Since we first reported an outbreak of adult parechovirus A3-associated myalgia in Yamagata, Japan in 2008, this disease has since been recognized across Japan, but has not yet been reported from other countries. AIM: We analysed 19 cases of parechovirus A3 infections identified in Yamagata in 2019 to further clarify the epidemiology of this disease. METHODS: We performed phylogenetic analyses of parechovirus A3 isolates and analysed the clinical manifestations and the genomic clusters. RESULTS: There were two clusters, with cluster 2019B replacing 2019 A around October/November. Phylogenetic analysis revealed that 2019B cluster strains and Australian recombinant strains, which appeared between 2012 and 2013, were grouped in one cluster at non-structural protein regions, suggesting that the ancestor to these regions of 2019B cluster strains were Australian recombinant lineage strains. The strains from both clusters caused various infections in children including myalgia. These findings strongly support that parechovirus A3 strains cause myalgia and other paediatric infections irrespective of the virus strains involved, including recombinant strains.　　. CONCLUSIONS: We have reported repeatedly sporadic cases of myalgia and here showed that recombinant strains also cause myalgia. We hope our experiences will help better understand these infections and possibly result in detection of more cases in the world.

Cerebral Venous Sinus Thrombosis After BNT162b2 mRNA COVID-19 Vaccination.

W present a rare case of cerebral venous sinus thrombosis after the BNT162b2 mRNA COVID-19 vaccine. A 61-year-old Japanese man developed a headache 10 days after the first dose of the vaccine. Magnetic resonance venography and contrast-enhanced brain MRI showed thrombosis in the superior sagittal sinus and the right transverse sinus. Anticoagulation with intravenous unfractionated heparin followed by oral warfarin was started. His headache improved, and brain MRI on day 22 showed resolution of thrombus. He was maintained on anticoagulation with warfarin and discharged without any neurological sequelae. This case is presented in the context of the relevant literature.

Cognitive impairment due to widespread enlarged perivascular spaces.

Perivascular spaces, also known as Virchow-Robin spaces, are usually considered as a normal, asymptomatic finding. However, this finding can occasionally demonstrate an atypical appearance and can be symptomatic. We report herein a rare case of cognitive impairment associated with extremely enlarged perivascular spaces. A 68-year-old Japanese woman visited our hospital with a 1-year history of progressive memory impairment. In addition to temporal disorientation and short-term memory impairment, neuropsychological testing showed frontal lobe-related symptoms such as slowed thinking processes, reduced verbal fluency, attention deficit, and reduced working memory. Magnetic resonance imaging of the brain showed widespread enlarged perivascular spaces almost symmetrically in the subcortical white matter of bilateral hemispheres, prominently in bilateral insulas, and frontal opercula. On 99mTc-ethyl cysteinate dimer single photon emission computed tomography, hypoperfusion was apparent in bilateral insulas and frontal opercula where enlarged periventricular spaces were prominent, whereas cerebral perfusion was preserved in areas where enlargement of perivascular spaces was mild or absent. Because symptoms were consistent with the distribution of the enlarged perivascular spaces and hypoperfusion in the brain, cognitive impairment due to enlarged perivascular spaces was diagnosed. Clinicians should note enlarged perivascular spaces as a potential cause of neurological deficits including cognitive impairment.

Atezolizumab-associated Dermatomyositis in Advanced Small-cell Lung Carcinoma.

Dermatomyositis is a rare immune-related adverse event caused by immune checkpoint inhibitors. We herein report a 75-year-old Japanese man with small-cell lung carcinoma who developed dermatomyositis after the administration of atezolizumab. He developed rashes on day 13 and myalgia and motor weakness on day 30 of the first administration of atezolizumab. Anti-transcriptional intermediary factor 1-gamma antibody was positive, and serum interleukin-6 levels were prominently elevated in the acute phase. Symptoms were improved by corticosteroid therapy. This is the first report of dermatomyositis associated with atezolizumab. Clinicians should be aware of the possibility of dermatomyositis after the administration of immune checkpoint inhibitors.

Antibody design using LSTM based deep generative model from phage display library for affinity maturation.

Molecular evolution is an important step in the development of therapeutic antibodies. However, the current method of affinity maturation is overly costly and labor-intensive because of the repetitive mutation experiments needed to adequately explore sequence space. Here, we employed a long short term memory network (LSTM)-a widely used deep generative model-based sequence generation and prioritization procedure to efficiently discover antibody sequences with higher affinity. We applied our method to the affinity maturation of antibodies against kynurenine, which is a metabolite related to the niacin synthesis pathway. Kynurenine binding sequences were enriched through phage display panning using a kynurenine-binding oriented human synthetic Fab library. We defined binding antibodies using a sequence repertoire from the NGS data to train the LSTM model. We confirmed that likelihood of generated sequences from a trained LSTM correlated well with binding affinity. The affinity of generated sequences are over 1800-fold higher than that of the parental clone. Moreover, compared to frequency based screening using the same dataset, our machine learning approach generated sequences with greater affinity.

Unilateral Upper Cervical Cord Infarction: A Report of Two Cases with Mild Neurological Symptoms Accompanying a Small Ischemic Lesion Detected by Brain MRI.

Spinal cord infarction (SCI) is rare, difficult to diagnose, and often fails to be detected by diffusion-weighted imaging (DWI) of spinal cord magnetic resonance imaging (MRI). Because the clinical features of SCI can vary widely, diagnosis during the acute phase of SCI is often challenging for clinicians. Although SCI shares similar etiologies with cerebral infarction, the characteristics of SCI without vessel dissection remain largely unknown. We present two older patients with mild neurological symptoms who each presented with a small, unilateral, upper cervical cord lesion, which was detected by thin-section, coronal DWI of brain MRI. Both unilateral small lesions were localized in the right lateral funiculus, and each patient showed good prognosis. The anatomical findings suggested that the pial collateral network surrounding the cervical cord contributed to lesion formation. Small and localized lesions have been associated with mild neurological symptoms and better short-term prognosis. The present report indicated that the use of thin-section coronal DWI when performing brain MRI may be helpful for the diagnosis of small, unilateral, upper cervical cord infarctions.

Dynamic 3D-CT angiography during swallowing for diagnosing hyoid bone or thyroid cartilage compression-induced thromboembolism.

A 76-year-old man was admitted because of visual loss in his right eye, and was diagnosed with central retinal artery occlusion. Brain MRI revealed asymptomatic acute infarctions in the right middle cerebral artery territory. The proximal right internal carotid artery had migrated into a retropharyngeal location, presenting a 50% stenosis with calcified plaques, and was compressed by the hyoid bone and thyroid cartilage during swallowing on dynamic 3D-CT angiography. Partial resection of the hyoid bone and thyroid cartilage was performed and the postoperative course was uneventful. This case supports the utility of dynamic 3D-CT angiography during swallowing for diagnosing hyoid bone or thyroid cartilage compression-induced thromboembolism.

Atezolizumab-associated encephalitis in metastatic lung adenocarcinoma: a case report.

BACKGROUND: In recent years, immune checkpoint inhibitors have been widely used as a crucial therapy in malignant tumors. Immune checkpoint inhibitors can cause various autoimmune side effects called immune-related adverse events because they generate an exaggerated inflammatory response. Encephalitis associated with atezolizumab has rarely been reported as an immune-related adverse event. A case of encephalitis caused by treatment with atezolizumab is presented. CASE PRESENTATION: A 56-year-old Japanese man with lung cancer previously treated with surgery and chemotherapy was admitted with high fever, consciousness disorder, and motor aphasia. His first atezolizumab treatment was 17 days earlier. Admission brain magnetic resonance imaging with gadolinium enhancement showed no abnormalities. Cerebrospinal fluid showed cell count 20/l, protein 166 mg/dl, glucose 73 mg/dl, and interleukin 6 82.9 pg/ml (normal< 8.7 pg/ml). Atezolizumab-induced encephalitis was diagnosed. His symptoms improved the day after steroid pulse therapy was started. Following steroid pulse therapy, oral prednisolone 30 mg was started and tapered. The cerebrospinal fluid findings normalized on day 14. He was discharged on day 16 without neurological sequelae. CONCLUSION: In this case of encephalitis associated with atezolizumab, prompt steroid pulse therapy led to a successful response, and the outcome was good. The cerebrospinal fluid level of interleukin 6 reflected the severity of the encephalitis well. Clinicians should be aware of the possibility of encephalitis after initiation of immune checkpoint inhibitors.

Mechanical thrombectomy utilising a collateral pathway in a patient with dysgenesis of the internal carotid artery.

We describe a case of acute middle cerebral artery occlusion in a patient with ipsilateral internal carotid artery dysgenesis successfully treated with mechanical thrombectomy utilising a collateral pathway. During the procedure, a triaxial system using a balloon guiding catheter, flexible large lumen aspiration catheter and stent retriever was advanced from the left vertebral artery to the occluded left middle cerebral artery through the left posterior communicating artery. Because proximal aspiration from the balloon guiding catheter alone might have insufficient suction force due to the retrograde blood flow from large vascular communications (e.g. vertebral artery union), the tip of the flexible large lumen aspiration catheter was set at the proximal left middle cerebral artery, and distal aspiration was added during stent retrieval. A thrombolysis in cerebral infarction 2b result was achieved after the first pass. In this case, identification of carotid canal hypoplasia on computed tomography allowed for an immediate attempt of this alternative approach, avoiding a delay in the time to reperfusion.

Transient Lesion of the Splenium of the Corpus Callosum after Acute Ischemic Stroke.

Two patients who showed transient lesions in the splenium of the corpus callosum (SCC) secondary to acute ischemic stroke are reported. Both patients had embolic strokes and showed an isolated lesion in the SCC on magnetic resonance imaging (MRI) 1-2 weeks after the onset of stroke, with a hyperintense lesion on diffusion-weighted imaging and decreased apparent diffusion coefficient values, with no symptoms related to the lesion. In both cases, the lesion disappeared on MRI approximately 1 week later. Clinicians should note that transient SCC lesions can occur following acute ischemic stroke and avoid misdiagnosing them and performing unnecessary examinations or treatment.

Clinical characteristics of 17 adult patients with epidemic myalgia associated with human parechovirus type 3 infection.

We investigated 17 adult cases (14 males and 3 females) of myalgia induced by human parechovirus type 3 (HPeV3) infection, treated during the summers of 2008, 2011, 2014, and 2016. The patients were aged between 21 and 50 years. The limbs and trunk of all patients were affected, and severe myalgia, muscle weakness, and decreased grip strength were observed. In addition to myalgia and muscle weakness, symptoms included fever in 14 (82%), upper respiratory inflammation in 8 (47%), gastroenteritis in 4 (24%), and scrotal pain in 4 (29% of males) patients. Tendon reflexes were preserved, and serum creatine kinase level increased in all but 1 patient. Spinal MRI was performed for 3 patients, with normal results. Musculoskeletal MRI scans showed abnormal signals in the femoral muscles in 2 of 5 patients. In a nerve conduction test, the frequency of F wave appearance in the median nerve was 40% or less in 5 of 9 patients, and repeater F waves were seen in 2 patients. Of these, 7 patients had infants in their families, and developed fever around the same time; they may have been infected by these infants. All patients recovered within 1-2 weeks. HPeV3 infection is characterized by severe myalgia, and is frequently observed in summer every 2-3 years.

Clinical and radiological diversity in genetically confirmed primary familial brain calcification.

Primary familial brain calcification (PFBC) is a rare neuropsychiatric disorder with characteristic symmetrical brain calcifications. Patients with PFBC may have a variety of symptoms, although they also may be clinically asymptomatic. Parkinsonism is one of the most common movement disorders; however, the underlying mechanism remains unclear. This condition is typically transmitted in an autosomal dominant fashion. To date, mutations in SLC20A2, PDGFRB, PDGFB, and XPR1 have been reported to cause PFBC. The aim of the study was to identify the genetic cause of brain calcification in probands from three PFBC families and in 8 sporadic patients and to perform clinical and radiological assessments focusing on parkinsonism in mutation carriers. Three familial PFBC probands and their relatives and eight sporadic patients affected with brain calcifications were enrolled in this study. Whole-exome sequencing identified three novel mutations: c.269G > T, p.(Gly90Val) and c.516+1G > A in SLC20A2 in familial cases, and c.602-1G > T in PDGFB in a sporadic patient. The c.516+1G > A mutation resulted in exon 4 skipping in SLC20A2 (p.Val144Glyfs*85). Dopamine transporter single photon emission computed tomography using 123I-ioflupane and 123I-metaiodobenzylguanidine cardiac scintigraphy revealed pre-synaptic dopaminergic deficit and cardiac sympathetic nerve dysfunction in two SLC20A2-related PFBC patients with parkinsonism.

Long lasting neutralization of C5 by SKY59, a novel recycling antibody, is a potential therapy for complement-mediated diseases.

Dysregulation of the complement system is linked to the pathogenesis of a variety of hematological disorders. Eculizumab, an anti-complement C5 monoclonal antibody, is the current standard of care for paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome (aHUS). However, because of high levels of C5 in plasma, eculizumab has to be administered biweekly by intravenous infusion. By applying recycling technology through pH-dependent binding to C5, we generated a novel humanized antibody against C5, SKY59, which has long-lasting neutralization of C5. In cynomolgus monkeys, SKY59 suppressed C5 function and complement activity for a significantly longer duration compared to a conventional antibody. Furthermore, epitope mapping by X-ray crystal structure analysis showed that a histidine cluster located on C5 is crucial for the pH-dependent interaction with SKY59. This indicates that the recycling effect of SKY59 is driven by a novel mechanism of interaction with its antigen and is distinct from other known pH-dependent antibodies. Finally, SKY59 showed neutralizing effect on C5 variant p.Arg885His, while eculizumab does not inhibit complement activity in patients carrying this mutation. Collectively, these results suggest that SKY59 is a promising new anti-C5 agent for patients with PNH and other complement-mediated disorders.

Whole-exome sequencing and digital PCR identified a novel compound heterozygous mutation in the NPHP1 gene in a case of Joubert syndrome and related disorders.

BACKGROUND: Joubert syndrome and related disorders (JSRD) is a clinically and genetically heterogeneous condition with autosomal recessive or X-linked inheritance, which share a distinctive neuroradiological hallmark, the so-called molar tooth sign. JSRD is classified into six clinical subtypes based on associated variable multiorgan involvement. To date, 21 causative genes have been identified in JSRD, which makes genetic diagnosis difficult. CASE PRESENTATION: We report here a case of a 28-year-old Japanese woman diagnosed with JS with oculorenal defects with a novel compound heterozygous mutation (p.Ser219*/deletion) in the NPHP1 gene. Whole-exome sequencing (WES) of the patient identified the novel nonsense mutation in an apparently homozygous state. However, it was absent in her mother and heterozygous in her father. A read depth-based copy number variation (CNV) detection algorithm using WES data of the family predicted a large heterozygous deletion mutation in the patient and her mother, which was validated by digital polymerase chain reaction, indicating that the patient was compound heterozygous for the paternal nonsense mutation and the maternal deletion mutation spanning the site of the single nucleotide change. CONCLUSION: It should be noted that analytical pipelines that focus purely on sequence information cannot distinguish homozygosity from hemizygosity because of its inability to detect large deletions. The ability to detect CNVs in addition to single nucleotide variants and small insertion/deletions makes WES an attractive diagnostic tool for genetically heterogeneous disorders.

Inflammatory Pseudotumor of the Brain Parenchyma with IgG4 Hypergammaglobulinemia.

A 58-year-old woman with a 1-month history of right hand clumsiness and speaking difficulty was admitted to our hospital. A neurological examination revealed sensory aphasia and right hemiparesis. Her laboratory tests showed elevated serum levels of IgG and IgG4, pancytopenia, and liver dysfunction. The results of the imaging studies of her abdomen were compatible with sclerosing cholangitis. Brain MRI showed extensive signal abnormalities in the left hemisphere on T2-weighted and fluid-attenuated inversion recovery (FLAIR) images, extending from left internal capsule to the cerebral peduncle with an irregularly enhancing lesion in the left parietal lobe. A brain biopsy revealed lymphocyte and plasma cell infiltration and reactive gliosis. Most of the plasma cells were IgG positive; however, IgG4-positive plasma cells were sparsely observed. After the initiation of betamethasone treatment, her symptoms and the brain MRI abnormalities showed significant improvement. The brain biopsy results did not meet the current criteria of IgG4-related disease. This is the first reported case of a tumefactive lesion of the brain parenchyma with serum IgG4 elevation, which was responsive to steroid treatment. The accumulation of a greater number of reports on the pathological investigation of cases of possible IgG4-related disease may help to elucidate the exact role of IgG4 in IgG4-related disorders.

Impact of nocturnal heart rate variability on cerebral small-vessel disease progression: a longitudinal study in community-dwelling elderly Japanese.

Recent evidence has shown an effect of ambulatory heart rate (HR) on cardiovascular events and mortality. Our objective was to determine whether ambulatory HR was related to the progression of cerebral small-vessel disease (SVD) or cognitive decline in community-dwelling elderly people. A cohort of 190 community-dwelling elderly people underwent an ambulatory blood pressure monitoring (ABPM), brain magnetic resonance imaging (MRI) and cognitive testing at baseline, with MRI and cognitive tests repeated 4 years later. HR variability in ABPM was quantified by the s.d. (s.d. and the root mean square of successive differences (RMSSD), and the relationship between HR variability and the progression of SVD/cognitive decline was investigated. We also assessed the association of nighttime HR variability and nocturnal HR dipping. The nighttime RMSSD of participants with the progression of SVD was significantly higher than that of those without progression of SVD (P<0.05). Moreover, nighttime RMSSD was independently associated with the progression of SVD (1 b.p.m. increment: odds ratio=1.13, 95% confidence interval=1.04-1.24, P<0.01). We failed to confirm an association between cognitive decline and nighttime HR variability. However, s.d. in the daytime and 24-h HR were independently related to cognitive decline (P<0.05). Nocturnal HR dipping was least in the top quartiles of nighttime HR variability, with a monotonic trend of nocturnal HR dipping that was dependent on the quartiles of nighttime HR variability indices (P<0.01). Increased HR variability during the night is a predictor of the progression of SVD in community-dwelling elderly people.

Change of carotid intima-media thickness is associated with age in elderly Japanese patients without a history of cardiovascular disease.

AIM: The present study aimed to evaluate the relationship between the change of carotid intima-media thickness (CIMT) and clinical characteristics in Japanese patients without a history of cardiovascular disease. METHODS: The study participants were 149 Japanese patients without a history of cardiovascular disease treated in our outpatient department. The in all participants CIMT was measured with ultrasonography at baseline and after a mean interval of 2.4 years. Study participants were divided into a middle-aged group (younger than 65 years: n = 59) and an elderly group (65 years or older: n = 90). The annual CIMT change (ΔCIMT) was calculated, and the associations between ΔCIMT and clinical characteristics, including age, were evaluated in both groups. RESULTS: The ΔCIMT was significantly correlated with age in all participants (r = 0.222; P < 0.05) and in elderly participants (r = 0.234; P < 0.05), but was not correlated with other risk factors. The annual ΔCIMT was significantly higher in elderly participants (0.015 ± 0.096 mm) than in middle-aged participants (-0.018 ± 0.088 mm; P < 0.05). Multivariate linear regression analysis with ΔCIMT as a dependent variable and risk factors as independent variables showed that ΔCIMT was significantly associated with age in all participants (ß = 0.002; P < 0.05) and in elderly participants (ß = 0.004; P < 0.05), but not with other risk factors. CONCLUSIONS: Annual CIMT change is associated with age, rather than with other clinical characteristics, including traditional cardiovascular risk factors, such as diabetes and hypertension, in elderly Japanese patients without a history of cardiovascular disease.

Impact of ambulatory blood pressure variability on cerebral small vessel disease progression and cognitive decline in community-based elderly Japanese.

BACKGROUND: Recent epidemiological studies reported a relationship between 24-hour ambulatory blood pressure (ABP) variability and cardiovascular events. However, the impact of ABP variability on small vessel disease (SVD) progression or cognitive decline in the elderly has seldom been investigated in community-based longitudinal studies. METHODS: Subjects (n = 210) underwent ABP monitoring, brain magnetic resonance imaging (MRI), and cognitive testing at baseline and 4 years later. ABP variability was quantified by the SD, weighted SD, coefficient of variation (CV), and average real variability (ARV). ABP variability parameters were divided into 2 groups by median values. RESULTS: Multivariable logistic regression analyses showed that higher systolic CV, diastolic weighted SD, and diastolic CV were significant predictors of SVD progression (P = 0.02, 0.03, and 0.02, respectively). In subjects with SVD on the first MRI, higher systolic and diastolic ARV also predicted progression (P = 0.04 and 0.03, respectively). Higher quartiles of systolic weighted SD and CV had higher incidences of SVD progression (P trend = 0.03 and 0.03, respectively, Cochran-Armitage test), and higher quartiles of systolic ARV had higher incidences of SVD progression in subjects with SVD on the first MRI (P trend = 0.03). Higher systolic ARV was an independent predictor of cognitive decline (P < 0.01), and higher tertiles of systolic ARV had higher incidences of cognitive decline (P trend = 0.02). CONCLUSIONS: This community-based longitudinal study found that increased ABP variability was associated with SVD progression, particularly in individuals with SVD at baseline. Higher systolic ARV predicted SVD progression and cognitive decline.