Safety of tapering tacrolimus dose in patients with well-controlled anti-acetylcholine receptor antibody-positive myasthenia gravis

BACKGROUND AND PURPOSE

Tapering immunosuppressants is desirable in patients with well-controlled myasthenia gravis (MG). However, the association between tapering of calcineurin inhibitor dosage and reduction-associated exacerbation is not known. The aim of this study was to clarify the frequency of reduction-associated exacerbation when tacrolimus is tapered in stable patients with anti-acetylcholine receptor antibody-positive MG, and to determine the factors that predict exacerbations.

METHODS

We retrospectively analyzed 115 patients in whom tacrolimus dosage was tapered. The reduction-associated exacerbation was defined as the appearance or worsening of one or more MG symptoms <3 months after the reduction.

RESULTS

Tacrolimus dosage was successfully tapered in 110 patients (96%) without any exacerbation. Five patients (4%) experienced an exacerbation, but symptoms were reversed in all patients when the tacrolimus dose was increased to the previous maintenance level. No patient developed an MG crisis. The age at onset was significantly earlier (30 vs. 56 years, P = 0.025) and the reduction in dosage was significantly larger (2.0 vs. 1.0 mg/day, P = 0.002) in patients with reduction-associated exacerbation than in those without exacerbation. The cut-off values determined in a receiver-operating characteristic curve analysis were 52 years (sensitivity, 57%; specificity, 100%) for the age at onset and 1.5 mg (sensitivity, 80%; specificity, 100%) for the dose reduction.

CONCLUSION

Tapering of tacrolimus was possible in most patients with well-controlled anti-acetylcholine receptor antibody-positive MG. Early age at onset and a large reduction from maintenance dosage were associated with exacerbation. Reductions ≤1.5 mg/day from the maintenance dosage should be considered for patients with late-onset disease.

Pembrolizumab-related systemic myositis involving ocular and hindneck muscles resembling myasthenic gravis: a case report

Background

Pembrolizumab is an immune-checkpoints inhibitor that enhances the immune response against cancer cells and therefore is useful for the treatment of several carcinomas. However, pembrolizumab sometimes perturbs the immune system resulting in various autoimmune neurological complications. In this situation, autoimmune myositis due to pembrolizumab is a rare but not-negligible complication. Here, we report two cases of autoimmune myositis due to pembrolizumab, with systemic myositis involving levator palpebrae superioris, extraocular and hindneck muscles.

Case presentation

Case 1 was a 78-year-old man with advanced urinary cancer referred to the neurological ward presenting with bilateral ptosis, restriction of eye movements, dropped head and weakness in the lower extremities after pembrolizumab administration. His blood examination showed elevated serum levels of creatine kinase with positive anti-PM-Scl 75 and anti-signal recognition particle antibodies. Needle electromyography and MRI suggested systemic inflammatory myopathy. There were no findings to indicate myocardial involvement on electrocardiogram or echocardiogram. Administration of intravenous methylprednisolone following plasma exchange ameliorated creatine kinase levels and inhibited the progression of clinical symptoms. Case 2 was a 72-year-old female with lung cancer and multiple metastasis, including lymph nodes and brain. She presented with back pain, right-sided ptosis, weakness of her neck extensors and flexors and elevated serum creatine kinase after receiving pembrolizumab. Although myositis specific autoantibodies were negative, needle electromyography and MRI suggested systemic inflammatory myopathy and muscle biopsy indicated necrotizing myopathy. There were no signs indicating heart dysfunction and her electrocardiogram was normal. Clinical symptoms and serum creatine kinase levels were ameliorated after the administration of intravenous methylprednisolone.

Conclusions

Both cases showed atypical extensive inflammatory myositis including levator palpebrae superioris, extraocular and hindneck muscles, resembling myasthenia gravis (MG), but they did not have MG-related antibodies. Edrophonium test was negative and showed no daily fluctuation. Two previously reported cases also presented with systemic necrotizing systemic myositis involving extraocular and facial muscles caused by pembrolizumab. Idiopathic inflammatory myositis evolving levator palpebrae superioris and ocular muscles is quite rare; however, myositis due to immune-checkpoint inhibitors may preferentially involve these muscles. This case report will alert physicians to the possibility of systemic inflammatory myopathy evolving levator palpebrae superioris, extraocular and hindneck muscles mimicking MG due to pembrolizumab.

Transgenic mice overexpressing miR-137 in the brain show schizophrenia-associated behavioral deficits and transcriptome profiles

Schizophrenia is a psychiatric disorder characterized by positive and negative symptoms and cognitive deficits. The exact cause of schizophrenia is still unknown, but substantial evidence indicates that it has a genetic component. Genome wide association studies demonstrate variants within miR-137 host gene are a risk factor for schizophrenia. However, the direct relationship between the pathophysiology of schizophrenia and the dosage of miR-137 remains unclear. Therefore, in this study, we generated transgenic mice overexpressing miR-137 (miR-137 Tg mice) with the neuron-specific Thy-1 promoter and examined schizophrenia-related phenotypes in these mice. Overexpression of miR-137 was observed in various brain regions of the miR-137 Tg mice, with down-regulation of putative miR-137 targets. MiR-137 Tg mice showed sensory gating deficits in a prepulse inhibition test, social deficits in a sociability and social novelty test, and cognitive deficits in a novel object recognition test. Interestingly, the predicted-altered pathways of the medial prefrontal cortex of miR-137 Tg mice were partially overlapped with those of the dorsolateral prefrontal cortex in postmortem brain of patients who died in equal to or less than 4 years after initial diagnosis of schizophrenia in published data. These results suggest that overexpression of miR-137 in the whole brain induces the several phenotypes that are relevant to aspects of psychiatric disorders, such as schizophrenia. Based on these findings, miR-137 Tg mice may have the potential to become a useful tool in researching the pathophysiology of psychiatric disorders.

Inpatient Enhanced Multidisciplinary Care Effects on the Quality of Life for Parkinson Disease: A Quasi-Randomized Controlled Trial

OBJECTIVES

To compare the effects of inpatient enhanced multidisciplinary care (EMC) and multidisciplinary rehabilitation (MR) on the symptoms and quality of life (QOL) of patients with Parkinson disease (PD) and to clarify the relation between reduction in symptoms and the improved QOL.

METHODS

This study was a quasi-randomized controlled (alternate allocation), assessor-blinded, single-center study. We recruited 80 patients with idiopathic Parkinson disease, Hoehn and Yahr stage 2 to 4, on stable medication. Patients were included in an EMC or MR group. Both rehabilitation programs were performed for 8 weeks (17 h/wk). Main outcome measures were Parkinson's Disease Questionnaire-39 and Unified Parkinson's Disease Rating Scale.

RESULTS

The EMC induced significant improvements in QOL compared to MR. We found that body axis symptoms (rising from a chair, posture, postural stability, falling, and walking) as well as nonmotor symptoms (depression) in patients with PD were relieved by the inpatient EMC.

CONCLUSIONS

Enhanced multidisciplinary care for patients with PD appears to be effective in improving the QOL. The improvement in motor and nonmotor symptoms, including depression, may contribute to the improved QOL.

Pontine hemorrhage accompanied by neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disorder caused by antibody to aquaporin-4 (AQP4). NMOSD can infrequently present as a complication of posterior reversible encephalopathy syndrome (PRES). Moreover, few cases of NMOSD patients with brain hemorrhage have been reported. We report a rare case of PRES together with NMOSD recurrence, subsequent to pontine hemorrhage after intravenous methylprednisolone (IVMP) therapy. A 51-year-old Japanese woman, with a history of hypertension and dyslipidemia, and recurrent episodes of left visual acuity disorder related to AQP4-positive NMOSD, developed blindness in the left eye. Brain MRI showed a hyperintense lesion in pons. She was initially diagnosed with recurrence of NMOSD and 1000 mg of IVMP was administered for 3 days. After the 3rd course of IVMP, she developed left-sided sensory disturbance, and blood pressure was increased to 202/127 mmHg. Brain computed tomography (CT) showed pontine hemorrhage, and she was referred to our hospital again. We diagnosed PRES associated with NMOSD recurrence, along with development of pontine hemorrhage induced by the increase in blood pressure resulting from IVMP. The patient was treated with nicardipine to strictly control blood pressure, and tranexamic acid and glycerol for pontine hemorrhage and PRES. We also extended IVMP for 5 consecutive days in total, followed by plasmapheresis. After therapy, blindness in the left eye improved to light perception. Collectively, anti-AQP4 antibody could induce PRES together with recurrent NMOSD, and pontine hemorrhage could thus be induced by blood pressure increases resulting from IVMP.

Improving the Quality of Synthetic FLAIR Images with Deep Learning Using a Conditional Generative Adversarial Network for Pixel-by-Pixel Image Translation

BACKGROUND AND PURPOSE

Synthetic FLAIR images are of lower quality than conventional FLAIR images. Here, we aimed to improve the synthetic FLAIR image quality using deep learning with pixel-by-pixel translation through conditional generative adversarial network training.

MATERIALS AND METHODS

Forty patients with MS were prospectively included and scanned (3T) to acquire synthetic MR imaging and conventional FLAIR images. Synthetic FLAIR images were created with the SyMRI software. Acquired data were divided into 30 training and 10 test datasets. A conditional generative adversarial network was trained to generate improved FLAIR images from raw synthetic MR imaging data using conventional FLAIR images as targets. The peak signal-to-noise ratio, normalized root mean square error, and the Dice index of MS lesion maps were calculated for synthetic and deep learning FLAIR images against conventional FLAIR images, respectively. Lesion conspicuity and the existence of artifacts were visually assessed.

RESULTS

The peak signal-to-noise ratio and normalized root mean square error were significantly higher and lower, respectively, in generated-versus-synthetic FLAIR images in aggregate intracranial tissues and all tissue segments (all P < .001). The Dice index of lesion maps and visual lesion conspicuity were comparable between generated and synthetic FLAIR images (P = 1 and .59, respectively). Generated FLAIR images showed fewer granular artifacts (P = .003) and swelling artifacts (in all cases) than synthetic FLAIR images.

CONCLUSIONS

Using deep learning, we improved the synthetic FLAIR image quality by generating FLAIR images that have contrast closer to that of conventional FLAIR images and fewer granular and swelling artifacts, while preserving the lesion contrast.

Bacteria-Host Interactions in Multiple Sclerosis

Multiple sclerosis (MS) is caused by a complex interaction of genetic and environmental factors. Numerous causative factors have been identified that play a role in MS, including exposure to bacteria. Mycobacteria, Chlamydia pneumoniae, Helicobacter pylori, and other bacteria have been proposed as risk factors for MS with different mechanisms of action. Conversely, some pathogens may have a protective effect on its etiology. In terms of acquired immunity, molecular mimicry has been hypothesized as the mechanism by which bacterial structures such as DNA, the cell wall, and intracytoplasmic components can activate autoreactive T cells or produce autoantibodies in certain host genetic backgrounds of susceptible individuals. In innate immunity, Toll-like receptors play an essential role in combating invading bacteria, and their activation leads to the release of cytokines or chemokines that mediate effective adaptive immune responses. These receptors may also be involved in central nervous system autoimmunity, and their contribution depends on the infection site and on the pathogen. We have reviewed the current knowledge of the influence of bacteria on MS development, emphasizing the potential mechanisms of action by which bacteria affect MS initiation and/or progression.

The effect of comprehensive physiotherapy-based rehabilitation on stooped posture in Parkinson's disease

[Purpose] The effect of physiotherapy on stooped posture in Parkinson's disease patients remains to be clarified. Therefore, the purpose of this study was to investigate whether comprehensive physiotherapy-based rehabilitation can improve stooped posture in Parkinson's disease patients. [Participants and Methods] The participants were Parkinson's disease patients with stooped posture. Outpatients were assigned to the control group and inpatients to the postural rehabilitation group. The outcomes measured were trunk bending angle, lumbar lordosis, and thoracic kyphosis. Each group was assessed at baseline and 1 month later. [Results] Of 22 participants identified, 20 were included, with 10 participants in the postural rehabilitation group and 10 in the control group. The age in the postural rehabilitation group was significantly greater than that in the control group, while other parameters were comparable in both groups. After the month-long intervention, the trunk bending angle and lumbar lordosis were significantly improved in the postural rehabilitation group compared to the control group. [Conclusion] The results showed improvement in stooped posture in the postural rehabilitation group as compared to the control group. Furthermore, improvement of lumbar lordosis accompanied improvement of stooped posture. These findings suggest that comprehensive physiotherapy-based rehabilitation may improve stooped posture in Parkinson's disease patients.

Prognostic value of sequencing-based minimal residual disease detection in patients with multiple myeloma who underwent autologous stem-cell transplantation

Background

Most patients with multiple myeloma (MM) are considered to be incurable, and relapse owing to minimal residual disease (MRD) is the main cause of death among these patients. Therefore, new technologies to assess deeper response are required.

Patients and methods

We retrospectively analyzed 125 patients with MM who underwent high-dose melphalan plus autologous stem-cell transplantation (ASCT) to detect MRD in autograft/bone marrow (BM) cells using a next-generation sequencing (NGS)-based method and allele-specific oligonucleotide-polymerase chain reaction (ASO-PCR).

Results

NGS-based method was applicable to 90% and this method had at least one to two logs greater sensitivity compared to ASO-PCR. MRD negative by NGS [MRD^NGS(−)] (defined as <10⁻⁶) in post-ASCT BM cases (n = 26) showed a significantly better progression-free survival (PFS) (96% at 4 years, P < 0.001) and overall survival (OS) (100% at 4 years, P =0.04) than MRD^NGS(+) in post-ASCT BM cases (n = 25). When restricting the analysis to the 39 complete response cases, patients who were MRD^NGS(−) (n = 24) showed a significantly better PFS than those that were MRD^NGS(+) (n = 15) (P =0.02). Moreover, MRD^NGS(−) in post-ASCT BM cases (n = 12) showed significantly a better PFS than MRD^NGS(+) cases (n = 7) where MRD was not detected by ASO-PCR (P = 0.001). Patients whose autografts were negative by NGS-based MRD assessment (<10⁻⁷) (n = 19) had 92% PFS and 100% OS at 4 years post-ASCT. Conversely, the NGS-based MRD positive patients who received post-ASCT treatment using novel agents (n = 49) had a significantly better PFS (P = 0.001) and tended to have a better OS (P= 0.214) than those that were untreated (n = 33).

Conclusions

Low level MRD detected by NGS-based platform but not ASO-PCR has significant prognostic value when assessing either the autograft product or BM cells post-ASCT.

Role of Malt1 protease activity in pathogenesis of inflammatory disorders mediated by FcγR signaling

MALT lymphoma-translocation protein 1 (Malt1) protease activity is triggered by stimulation of various immune receptors. Activation of Malt1 protease induces cleavage of negative regulators for immune responses, resulting in lymphocytes activation. Although Malt1 protease mediates the signaling process downstream of the T cell, B cell, and dectin receptors, its contribution in Fcγ receptor (FcγR) signaling has not been elucidated. In this study, we investigated the role of Malt1 protease activity in FcγR signaling using Malt1 protease-deficient (PD) mouse. In addition, role of Malt1 protease for the development of FcγR-mediated autoimmune disease was also investigated in vivo. Malt1 protease cleaves their substrates, such as RelB and cylindromatosis (CYLD). However, the Malt1 proteolytic activity was silenced in the Malt1 PD mice. Production of inflammatory cytokines via FcγR stimulation was decreased on dendritic cells prepared from Malt1 PD mice. In FcγR-dependent murine immune thrombocytopenia (ITP) model, gene expressions of the inflammatory cytokines in the spleen of Malt1 PD mice were lower than those of WT mice. Then, Malt1 PD mice protected the development of thrombocytopenia. These results clearly figured out that Malt1 protease activity plays an important role in the activation of innate immune cells via FcγR, and the development of FcγR-mediated autoimmune diseases. Therefore, Malt1 is an attractive target for the treatment of inflammatory diseases mediated by FcγR.

Photoexcited Muon Spin Spectroscopy: A New Method for Measuring Excess Carrier Lifetime in Bulk Silicon

We have measured excess carrier lifetime in silicon using photoexcited muon spin spectroscopy. Positive muons implanted deep in a wafer can interact with the optically injected excess carriers and directly probe the bulk carrier lifetime while minimizing the effect from surface recombination. The method is based on the relaxation rate of muon spin asymmetry, which depends on the excess carrier density. The underlying microscopic mechanism has been understood by simulating the four-state muonium model in Si under illumination. We apply the technique to different injection levels and temperatures, and demonstrate its ability for injection- and temperature-dependent lifetime spectroscopy.

Anti-NMDA receptor encephalitis due to large-cell neuroendocrine carcinoma of the uterus

A 44-year-old woman presented with a large-cell neuroendocrine carcinoma and uterine endometrioid carcinoma with anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis. Following the diagnosis of uterine cancer, the patient suddenly developed psychosis with abnormal behaviors, delusions, irritability, and forgetfulness. The cerebrospinal fluid tested positive for anti-NMDAR antibodies (encoding the NR1 subunit). The patient was diagnosed with paraneoplastic limbic encephalitis due to uterine cancer. Histology of multiple abdominal metastatic samples revealed a neuroendocrine tumor. Her consciousness improved temporarily after tumor resection and comprehensive immunomodulatory therapy. On day 104 after admission, the patient died of multiple organ failure. The autopsy revealed a perivascular infiltration of inflammatory cells in the amygdala and NMDAR-positive cells in the primary uterine cancer. Our findings demonstrated that neuroendocrine tumors can induce anti-NMDAR encephalitis, which is consistent with three previous reports. A comprehensive treatment with resection of the carcinoma, immunoglobulins, and plasma exchange can induce a partial improvement of the symptoms.