Case report: Reversible brain atrophy with low titer anti-amphiphysin antibodies related to gastric adenocarcinoma.

Amphiphysin (AMPH) autoimmunity is associated with a variety of neurological complications, including encephalitis, peripheral neuropathy, myelopathy, and cerebellar syndrome. Its diagnosis is based on clinical neurological deficits and the presence of serum anti-AMPH antibodies. Active immunotherapy, such as intravenous immunoglobulins, steroids, and other immunosuppressive therapies, has been reported to be effective in most patients. However, the extent of recovery varies depending on the case. Herein, we report the case of a 75-year-old woman with semi-rapidly progressive systemic tremors, visual hallucinations, and irritability. Upon hospitalization, she developed a mild fever and cognitive impairment. Brain magnetic resonance imaging (MRI) showed semi-rapidly progressive diffuse cerebral atrophy (DCA) over 3 months, while no clear abnormal intensities were observed. The nerve conduction study revealed sensory and motor neuropathy in the limbs. The fixed tissue-based assay (TBA) failed to detect antineuronal antibodies; however, based on commercial immunoblots, the presence of anti-AMPH antibodies was suspected. Therefore, serum immunoprecipitation was performed, which confirmed the presence of anti-AMPH antibodies. The patient also had gastric adenocarcinoma. High-dose methylprednisolone, and intravenous immunoglobulin were administered and tumor resection was performed, resulting in resolution of the cognitive impairment and improvement in the DCA on the post-treatment MRI. After immunotherapy and tumor resection, the patient's serum was analyzed using immunoprecipitation, which showed a decrease in the level of anti-AMPH antibodies. This case is noteworthy because the DCA showed improvement after immunotherapy and tumor resection. Additionally, this case demonstrates that negative TBA with positive commercial immunoblots do not necessarily indicate false positive results.

Influences of sleep and lifestyle factors on the risk for covid-19 infections, from internet survey of 10,000 Japanese business workers.

We conducted an internet survey to assess sociodemographic variables, lifestyle factors, sleep problems, and comorbidities for sleep apnea syndrome (SAS) in COVID-19 and influenza (FLU) infections. Data from 10,323 workers (50.0% male) were analyzed. COVID-19 was diagnosed in 144 subjects (COVID-19+), and 8,693 were classified as not suspected to be infected (COVID-19-). SAS had been diagnosed in 35.4% of the COVID-19+ subjects, but only 231 (2.7%) of the 8,693 COVID-19- subjects. COVID-19+ subjects were more susceptible to FLU (35.4%) compared to COVID-19- subjects (3.0%). A multivariate analysis revealed that higher risks of COVID-19+ were linked to the following factors: going out without a face mask (OR 7.05, 95% CI 4.53-11.00), FLU+ (OR 6.33, 95% CI 3.80-10.54), excessive exercise before going to sleep (OR 2.10, 95% CI 1.63-2.70), SAS+ (OR 5.08, 95% CI 2.88-8.94), younger age (OR 1.05, 95% CI 1.03-1.07), falling sleep while sitting or talking with someone (OR 3.70, 95% CI 2.30-5.95), and use of hypnotics (OR 2.28, 95% CI 1.20-4.30). Since sleep impairment played a relatively small role in COVID-19+/SAS- subjects, we assume that SAS itself was a more significant risk factor for COVID-19 infection rather than sleep impairment. A better understanding of the mechanisms that result in increased susceptibility to COVID-19 in SAS is vital for helping prevent COVID-19.

Muscle magnetic resonance imaging abnormality in neuroleptic malignant syndrome: a case report.

BACKGROUND: Neuroleptic malignant syndrome (NMS) is a rare and occasionally fatal undesirable reaction to dopamine antagonists, and its phenotype is diverse owing to causative drugs. Classically, elevation of serum creatine kinase is described in NMS. Some reports have described muscular pathological findings; however, muscle magnetic resonance imaging (MRI) has not been reported previously. CASE PRESENTATION: A 63-year-old woman with a history of schizophrenia presented to our hospital with a high fever, excessive sweating, muscle weakness, and elevated serum creatine kinase levels. Muscle MRI revealed T2 high-intensity lesions in several muscles with gadolinium enhancement, and the pathology of the muscle biopsy showed a very mild presence of muscle fiber necrosis and regeneration with type 2c fibers without inflammation. Her symptoms resolved by treatment with levodopa/carbidopa, dantrolene. Finally, the patient was diagnosed with NMS. CONCLUSIONS: This is the first report of muscle MRI abnormalities in a patient with NMS. Muscle MRI abnormalities in NMS may be associated with non-inflammatory myopathic changes. The cause of creatine kinase elevation cannot be explained by abnormal strong muscle contraction nor inflammation.

A computational model to explore how temporal stimulation patterns affect synapse plasticity.

Plasticity-related proteins (PRPs), which are synthesized in a synapse activation-dependent manner, are shared by multiple synapses to a limited spatial extent for a specific period. In addition, stimulated synapses can utilize shared PRPs through synaptic tagging and capture (STC). In particular, the phenomenon by which short-lived early long-term potentiation is transformed into long-lived late long-term potentiation using shared PRPs is called "late-associativity," which is the underlying principle of "cluster plasticity." We hypothesized that the competitive capture of PRPs by multiple synapses modulates late-associativity and affects the fate of each synapse in terms of whether it is integrated into a synapse cluster. We tested our hypothesis by developing a computational model to simulate STC, late-associativity, and the competitive capture of PRPs. The experimental results obtained using the model revealed that the number of competing synapses, timing of stimulation to each synapse, and basal PRP level in the dendritic compartment altered the effective temporal window of STC and influenced the conditions under which late-associativity occurs. Furthermore, it is suggested that the competitive capture of PRPs results in the selection of synapses to be integrated into a synapse cluster via late-associativity.

Case Report: Paraneoplastic Hashimoto's Encephalopathy Associated With Lymphomatosis Cerebri With Periodic Synchronous Discharges Resembling Creutzfeldt-Jakob Disease.

Hashimoto's encephalopathy (HE) is an autoimmune encephalopathy that presents with various clinical symptoms, including cognitive deterioration, convulsive seizures, and personality changes. HE is associated with thyroid autoimmunity; however, few cases have been reported to develop as paraneoplastic syndrome. Herein, we report the case of a 73-year-old woman with onset of rapidly progressive dementia. Brain magnetic resonance imaging showed diffuse T2 hyperintensity areas involving the bilateral cerebral white matter, right midbrain tegmental area, left cerebral peduncle, and right middle cerebellar peduncle without clear diffusion hyperintensities and gadolinium enhancement. Her neurological symptoms worsened rapidly, and she presented with the apallic syndrome. Electroencephalogram showed periodic synchronous discharge, suggestive of Creutzfeldt-Jakob disease. However, a brain biopsy revealed infiltration of atypical lymphoid cells expressing CD20, and the anti-NH2 terminal of the α-enolase antibody was detected, diagnosing the complication with lymphomatosis cerebri and HE. High-dose intravenous methylprednisolone therapy and oral prednisolone with whole cranial irradiation enabled her to have simple conversations and consume food orally; however, severe cognitive impairment persisted. Although HE is a rare complication of malignant lymphoma, clinicians should be aware that it could be strongly suspected if the clinical symptoms worsen in the absence of imaging changes.

Disseminated Bacillus Calmette-Guérin (BCG) infection and acute exacerbation of interstitial pneumonitis: an autopsy case report and literature review.

BACKGROUND: Intravesical administration of Bacillus Calmette-Guérin (BCG) has proven useful for treatment and prevention of recurrence of superficial bladder cancer and in situ carcinoma. However, fatal side effects such as disseminated infections may occur. Early diagnosis and accurate therapy for interstitial pneumonitis (IP) are important because exacerbation of IP triggered by infections is the major cause of death. Although some fatality reports have suggested newly appeared IP after intravesical BCG treatment, to our knowledge, there are no reports which have demonstrated acute exacerbation of existing IP. Moreover, autopsy is lacking in previous reports. We report the case of a patient with fatal IP exacerbation after BCG instillation and the pathological findings of the autopsy. CASE PRESENTATION: A 77-year-old man with a medical history of IP was referred to our hospital because of fever and malaise. He had received an intravesical injection of BCG 1 day before the admission. His fever reduced after the use of antituberculosis drugs, so he was discharged home. He was referred to our hospital again because of a high fever 7 days after discharge. On hospitalisation, he showed high fever and systemic exanthema. Hepatosplenomegaly and myelosuppression were also observed. Biopsies revealed multiple epithelioid cell granulomas with Langhans giant cells of the liver and bone marrow. Biopsy DNA analyses of Mycobacterium bovis in the bone marrow, sputum, and blood were negative. His oxygen demand worsened drastically, and the ground-glass shadow expanded on the computed tomography scan. He was diagnosed with acute exacerbation of existing IP. We recommenced the antituberculosis drugs with steroid pulse therapy, but he died on day 35 because of respiratory failure. The autopsy revealed a diffuse appearance of multiple epithelioid cell granulomas with Langhans giant cells in multiple organs, although BCG was not evident. CONCLUSIONS: We report the first case of acute exacerbation of chronic IP by BCG infection. This is also the first case of autopsy of a patient with acute exacerbation of existing IP induced by intravesical BCG treatment. Whether the trigger of acute IP exacerbation is infection or hypersensitivity to BCG is still controversial, because pathological evidence confirming BCG infection is lacking. Physicians who administer BCG against bladder cancer should be vigilant for acute exacerbation of IP.

Parallel enlargement of Marinesco bodies and nuclei and progressive deposition of p62 in pigmented neurons of the substantia nigra.

Marinesco bodies (MBs) are spherical nuclear inclusions found in pigmented neurons of the substantia nigra. Although MBs are abundant in senescent brains, how they are related to aging processes remains unclear. Here, we performed a morphometric analysis of midbrain pigmented neurons to identify the possible influence of MBs on nuclear size. The transected area of the nucleus (nuclear area) was larger in the presence of MBs and was correlated with the area of MB (MB area) in all tested brains. The MB-associated nuclear enlargement was significant even after MB areas were subtracted from nuclear areas. Moreover, higher MB immunoreactivity of p62 was detected in the nucleoplasm of the enlarged MB-associated nuclei. This study on human brains is the first quantitative approach demonstrating MB-associated nuclear enlargement and progressive accumulation of small nucleoplasmic materials. Although cellular hypertrophy is usually considered to be an indication of the upregulation of cellular function, this might not always be the case. These findings suggest that an age-related decline of ubiquitin-proteasome and autophagy system activity and stagnation of undegradable materials are one of the candidate mechanisms to explain the age-related decline of neural activity in the substantia nigra.

Secondary cardiac involvement in anti-SRP-antibody-positive myopathy: an 87-year-old woman with heart failure symptoms as the first clinical presentation.

BACKGROUND: Necrotizing myopathy (NM) is defined by the dominant pathological feature of necrosis of muscle fibers without substantial lymphocytic inflammatory infiltration. Anti-signal recognition particle (SRP)-antibody-positive myopathy is related to NM. Anti-SRP-antibody-positive myopathy can comorbid with other disorders in some patients, however, comorbidity with malignant tumor and myopericarditis has still not been reported. CASE PRESENTATION: An 87-year-old woman with dyspnea on exertion and leg edema was referred to our hospital because of suspected heart failure and elevated serum creatine kinase level. Upon hospitalization, she developed muscle weakness predominantly in the proximal muscles. Muscle biopsy and immunological blood test led to the diagnosis of anti-SRP-antibody-positive myopathy. A colon carcinoma was also found and surgically removed. The muscle weakness remained despite the tumor resection and treatment with methylprednisolone. Cardiac screening revealed arrhythmia and diastolic dysfunction with pericardial effusion, which recovered with intravenous immunoglobulin (IVIg) treatment. CONCLUSIONS: We reported the first case of anti-SRP-positive myopathy comorbid with colon carcinoma and myopericarditis. This case is rare in the point that heart failure symptoms were the first clinical presentation. The underlying mechanism is still not clear, however, physicians should be carefully aware of the neoplasm and cardiac involvement in anti-SRP-antibody positive-myopathy patients and should consider farther evaluation and management.

Cinnamic acid derivatives inhibit hepatitis C virus replication via the induction of oxidative stress.

Several cinnamic acid derivatives have been reported to exhibit antiviral activity. In this study, we prepared 17 synthetic cinnamic acid derivatives and screened them to identify an effective antiviral compound against hepatitis C virus (HCV). Compound 6, one of two hit compounds, suppressed the viral replications of genotypes 1b, 2a, 3a, and 4a with EC50 values of 1.5-8.1 µM and SI values of 16.2-94.2. The effect of compound 6 on the phosphorylation of Tyr705 in signal transducer and activator of transcription 3 (STAT3) was investigated because a cinnamic acid derivative AG490 was reported to suppress HCV replication and the activity of Janus kinase (JAK) 2. Compound 6 potently suppressed HCV replication, but it did not inhibit the JAK1/2-dependent phosphorylation of STAT3 Tyr705 at the same concentration. Furthermore, a pan-JAK inhibitor tofacitinib potently impaired phosphorylation of STAT3 Tyr 705, but it did not inhibit HCV replication in the replicon cells and HCV-infected cells at the same concentration, supporting the notion that the phosphorylated state of STAT3 Tyr705 is not necessarily correlated with HCV replication. The production of reactive oxygen species (ROS) was induced by treatment with compound 6, whereas N-acetyl-cysteine restored HCV replication and impaired ROS production in the replicon cells treated with compound 6. These data suggest that compound 6 inhibits HCV replication via the induction of oxidative stress.