Investigating the NLRP3 inflammasome and its regulator miR-223-3p in multiple sclerosis and experimental demyelination.

Innate immune signaling pathways are essential mediators of inflammation and repair following myelin injury. Inflammasome activation has recently been implicated as a driver of myelin injury in multiple sclerosis (MS) and its animal models, although the regulation and contributions of inflammasome activation in the demyelinated central nervous system (CNS) are not completely understood. Herein, we investigated the NLRP3 (NBD-, LRR- and pyrin domain-containing protein 3) inflammasome and its endogenous regulator microRNA-223-3p within the demyelinated CNS in both MS and an animal model of focal demyelination. We observed that NLRP3 inflammasome components and microRNA-223-3p were upregulated at sites of myelin injury within activated macrophages and microglia. Both microRNA-223-3p and a small-molecule NLRP3 inhibitor, MCC950, suppressed inflammasome activation in macrophages and microglia in vitro; compared with microglia, macrophages were more prone to inflammasome activation in vitro. Finally, systemic delivery of MCC950 to mice following lysolecithin-induced demyelination resulted in a significant reduction in axonal injury within demyelinated lesions. In conclusion, we demonstrate that NLRP3 inflammasome activity by macrophages and microglia is a critical component of the inflammatory microenvironment following demyelination and represents a potential therapeutic target for inflammatory-mediated demyelinating diseases, including MS. Cover Image for this issue: https://doi.org/10.1111/jnc.15422.

Primary neuroendocrine tumor of the pineal gland: a case report.

INTRODUCTION: Primary intracranial neuroendocrine tumors are exceedingly rare, with few cases in the literature. We present a case of a primary neuroendocrine carcinoma of the pineal gland, which is the second that has ever been reported. CASE PRESENTATION: A 53-year-old male patient presented with vomiting, weakness, and headaches. Imaging revealed a lesion in the pineal region, which was surgically resected. This mass was characterized by histology as a neuroendocrine carcinoma, given the presence of neuroendocrine markers and cytokeratin markers with absence of a primary lesion elsewhere on imaging. CONCLUSIONS: There are currently no guidelines on the management of primary intracranial neuroendocrine tumors. In this case, the patient underwent surgical resection and craniospinal radiotherapy. He subsequently received one cycle of chemotherapy with temozolomide, an alkylating agent, but he unfortunately did not tolerate treatment. A multidisciplinary decision was made along with the patient and his family to focus on palliative care. Eighteen months after the initial presentation, disease recurred in the patient's neck. The patient underwent resection to control the metastases, with a plan to follow with radiotherapy and chemotherapy. Unfortunately, the patient became unwell and died at 21 months after initial diagnosis. This demonstrates a need for continued research and reporting on this uncommon disease entity.

Late recurrence of choroid plexus carcinoma.

BACKGROUND: Choroid plexus carcinomas (CPC) are rare malignant brain tumours arising from the choroid plexus epithelium. CPC are most common in the paediatric population, particularly those under 2 years of age. Common presentations include headache, diplopia and signs of increased intracranial pressure such as nausea and vomiting. Infants may present with increased head circumference, bulging fontanelles, splayed cranial sutures and/or neurological delay. Diagnosis is made via radiological and histological analysis. MANAGEMENT AND PROGNOSIS: Gross total resection (GTR) is the preferred treatment and infers the best survival rate, but despite this, prognosis remains poor. The utility of chemotherapy and/or radiation in CPC management remains controversial, and an optimal treatment regimen has not been identified. Even with GTR, recurrence is common and usually occurs within months after resection. Delayed recurrence is exquisitely rare and has been reported very few times to date. CASE PRESENTATION: Here, we present a rare case of delayed CPC recurrence 10 years after initial presentation. A 2-month-old male was diagnosed with CPC and received GTR, chemotherapy and stem cell transplant. The patient presented with a recurrent CPC 10 years after the initial diagnosis. CONCLUSIONS: This case demonstrates the importance of long-term surveillance and raises questions regarding the natural history, recurrence patterns and factors contributing to long-term relapse in CPC. Further research should be targeted at identifying patient factors contributing to increased risk of late recurrence and whether adjuvant treatments play any role in decreasing this.

Interleukin-1 receptor antagonist: An exploratory plasma biomarker that correlates with disability and provides pathophysiological insights in relapsing-remitting multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is a chronic inflammatory demyelinating and neurodegenerative disorder. Interleukin-1 receptor antagonist (IL-1RA) is an endogenous soluble antagonist of the IL-1 receptor and blocks the pro-inflammatory effects of IL-1ß known to contribute to MS pathology. The objectives of this study were to determine whether IL-1RA is associated with disability in MS and how this correlates with neurofilament light (NfL) levels in cerebrospinal fluid (CSF). METHODS: Peripheral blood and CSF were collected from consenting MS patients. Patient demographic and clinical variables, including past relapse activity, were also collected. Circulating levels of IL-1RA, IL-18, and IL-1ß were measured in plasma; IL-1RA and NfL were measured in the CSF via Bio-plex multiplex immunoassay kits and ELISA, respectively. IL-1RA expression was investigated in vitro using primary human macrophages and microglia, and in situ using post-mortem MS tissue. RESULTS: Following a multiple regression analysis, IL-1RA levels in plasma correlated with expanded disability status scale score independent of all other variables. In a separate cohort, CSF IL-1RA significantly correlated with NfL. In vitro, induction of the NLRP3 inflammasome, a pathological hallmark within MS lesions, led to increased release of IL-1RA from primary human microglia and macrophages. In the CNS, IL-1RA+ macrophages/microglia were present at the rim of mixed active/inactive MS lesions. CONCLUSIONS: Results presented in this study demonstrate that IL-1RA is a novel exploratory biomarker in relapsing-remitting MS, which correlates with disability and provides mechanistic insights into the regulatory inflammatory responses within the demyelinated CNS.

Corpora amylacea in a leiomyoma of soft tissue.

A case of myxoid leiomyoma of deep soft tissue is described. The patient was a 42-year-old woman who presented with menorrhagia, and an ischiorectal mass was identified. A total hysterectomy was performed, and the mass was removed. On gross examination, the mass was 6cm x 5cm x 4cm and had a mucoid cut surface. Histologic examination revealed a myxoid leiomyoma with abundant intracellular corpora amylacea (CA). An infarcted leiomyoma was present in the hysterectomy specimen. The patient remains well, with no evidence of recurrence 3 years after surgery. Leiomyomas of deep soft tissue are rare, and, to our knowledge, none have been described containing CA.

Comparison of multifrequency bioelectrical impedance analysis with dual-energy X-ray absorptiometry for assessment of percentage body fat in a large, healthy population.

BACKGROUND: Bioelectrical impedance analysis (BIA) is widely used in clinics and research to measure body composition. However, the results of BIA validation with reference methods are contradictory, and few data are available on the influence of adiposity on the measurement of body composition by BIA. OBJECTIVE: The goal was to determine the effects of sex and adiposity on the difference in percentage body fat (%BF) predicted by BIA compared with dual-energy X-ray absorptiometry (DXA). DESIGN: A total of 591 healthy subjects were recruited in Newfoundland and Labrador. %BF was predicted by using BIA and was compared with that measured by DXA. Methods agreement was assessed by Pearson's correlation and Bland and Altman analysis. Differences in %BF among groups based on sex and adiposity were analyzed by using one-factor analysis of variance with Bonferroni correction. RESULTS: Correlations between BIA and DXA were 0.88 for the whole population, 0.78 for men, and 0.85 for women. The mean %BF determined by BIA (32.89 +/- 8.00%) was significantly lower than that measured by DXA (34.72 +/- 8.66%). The cutoffs were sex specific. BIA overestimated %BF by 3.03% and 4.40% when %BF was <15% in men and <25% in women, respectively, and underestimated %BF by 4.32% and 2.71% when %BF was >25% in men and >33% in women, respectively. CONCLUSIONS: BIA is a good alternative for estimating %BF when subjects are within a normal body fat range. BIA tends to overestimate %BF in lean subjects and underestimate %BF in obese subjects.

Rupture of middle cerebral artery aneurysm in a neonate: case report and review of the literature.

Intracranial hemorrhage because of rupture of a cerebral aneurysm is extremely rare in the neonatal period. Delayed diagnosis contributes to high mortality and morbidity. The authors report an extremely rare case of a middle cerebral artery aneurysm diagnosed and treated shortly after birth. Extensive review of the literature is presented. The patient died 4 years after surgery.