A characteristic increase in multiple-unit activity (MUA volley) synchronized with the pulsatile secretion of luteinizing hormone (LH) by the pituitary gland was recorded from electrodes chronically implanted in the medial basal hypothalamus of ovariectomized goats. The MUA volley always preceded the LH pulse, and the temporal correlation was consistent even when the pulse frequency was altered with an anesthetic or exogenous steroids. The electrophysiological manifestation of the hypothalamic ‘pulse generator’ governing the secretion of gonadotropin-releasing hormone was thus demonstrated in the ruminant.

OBJECTIVEMedulloblastoma is a type of malignant tumor arising in the cerebellum. The clinical importance of programmed cell death 1 ligand–1 (PD-L1) expression in medulloblastoma remains unknown. The aim of the present study was to examine the expression of PD-L1 and tumor-infiltrating T cells, and to evaluate their relationships to the prognosis of patients with medulloblastoma.METHODSThe authors immunohistochemically analyzed PD-L1 expression and CD3+ and CD8+ lymphocyte infiltrations in tumor specimens from 16 patients with medulloblastoma.RESULTSHigh expression of PD-L1 was observed in 9 (56.3%) of 16 samples studied. High expression of PD-L1 was associated with low infiltrations of CD3+ or CD8+ lymphocytes. Patients with high expression of PD-L1 had shorter progression-free survival and overall survival times than those with low expression (p = 0.076 and p = 0.099, respectively). In addition, patients with high expression of PD-L1 and with low infiltration of CD8+ lymphocytes had a significantly worse outcome, with a 5-year survival rate of 15%, as compared with the other patients, who had a 5-year survival rate of nearly 90% (p = 0.0048 for progression-free survival and p = 0.010 for overall survival).CONCLUSIONSThese findings indicate that PD-L1 expression was associated with a reduced infiltration of CD8+ T cells and poor prognosis in human medulloblastoma.

Multinodular and vacuolating neuronal tumors (MVNT) have been referred to as distinctive neuronal tumors whose characteristic features include multiple nodules localized in the subcortical white matter. MVNT are composed of vacuolating dysplastic neurons reactive to HuC/HuD. A significant overexpression of alpha-internexin (INA) limited to the stroma of nodules was reported in one tumor. Since genetic analyses have failed to demonstrate any consistent alterations, the nosological position as well as the nature of MVNT, namely, neoplastic or dysplastic, remains unclear. We herein present another example of MVNT involving the amygdala and anterior hippocampus in a 41-year-old man. In addition to the nodular lesions described earlier, we found INA-positive ribbon-like lesions that replaced neuropil and extended along the hippocampal gray matter. We also identified dysplastic neurons infiltrating into the CA4 hilus of the hippocampus. Intense INA expression was present in the stroma as well as the cytoplasmic membrane of dysplastic neurons and their processes. While the invasiveness suggested a neoplasm, a relatively restrictive, either nodular or ribbon-like growth pattern with INA-positive abnormal neuropil suggested a hamartoma. Such quasi-tumors should be accommodated in the World Health Organization classification of tumors of the central nervous system, as are dysembryoplastic neuroepithelial tumor and Lhermitte-Duclos disease.

Even though this prediction method does not offer perfect simulation of human taste sensations, the artificial taste sensor may be useful for predicting the bitterness intensity of elemental diets containing various flavors in the absence of results from full gustatory sensation tests.