A Rapidly Growing Cervical Meningeal Melanocytoma with a Dumbbell-Shaped Extension.

BACKGROUND: Meningeal melanocytoma is a rare benign lesion found in the central nervous system. Preoperative diagnosis of meningeal melanocytoma is often a diagnostic challenge, as the clinical and neurologic features are often nonspecific. Various characteristics, including the natural course of this tumor, remain poorly understood. We report a case of a rapidly growing dumbbell-shaped melanocytoma compressing the spinal cord that manifested 2 years after a tumor was identified at the right C2-C3 foramen. CASE DESCRIPTION: A 40-year-old, right-handed man presented with a 2-month history of right palm and left leg numbness. Magnetic resonance imaging of the cervical spine showed a dumbbell-shaped tumor at the right C2-C3 foramen with extension into the central canal. The lesion was hyperintense on T1-weighted images and hypointense to isointense on T2-weighted images. Contrast enhancement was not visualized clearly. Fluorodeoxyglucose-positron emission tomography with computed tomography showed intense uptake in the lesion. The patient's history included a small lesion that had been localized at the right C2-C3 foramen 2 years before admission. The pathologic findings were consistent with melanocytoma. CONCLUSIONS: It is important to include meningeal melanocytoma in the differential diagnosis of dumbbell tumors, as meningeal melanocytomas may show rapid progression.

Histamine type 1 receptor deficiency reduces airway inflammation in a murine asthma model.

BACKGROUND: Histamine plays an important role in immediate and late immune responses. The histamine type 1 (H1) receptor is expressed on several immune cell populations, but its role in a murine model of asthma remains unclear. The present study evaluated the role of histamine H1 receptors in airway allergic inflammation by comparing the development of bronchial asthma in histamine H1 receptor gene knockout (H1RKO) and wild-type mice. METHODS: H1RKO and wild-type mice were sensitized by intraperitoneal injection of ovalbumin (OVA) or saline, and then challenged with aerosolized OVA or saline. Ventilatory timing in response to inhaled methacholine was measured, and samples of blood, bronchoalveolar lavage, and lung tissues were taken 24 h after the last OVA challenge. RESULTS: OVA-treatedwild-type mice showed significantly increased airway eosinophilic infiltration, and airway response to methacholine compared to OVA-treated H1RKO mice. The serum level of immunoglobulin E and levels of interleukin (IL)-4, IL-5, IL-13, and TGF-beta1 in bronchoalveolar lavage fluid were lower in OVA-treated H1RKO mice than in OVA-treated wild-type mice, but there was no significant difference in interferon-gamma expression. Overall, deletion of histamine H1 receptors reduced allergic responses in a murine model of bronchial asthma. CONCLUSION: Histamine plays an important role via H1 receptors in the development of T helper type 2 responses to enhance airway inflammation.