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Notes: Reelin is an extracellular matrix protein secreted by a variety of cell types throughout the developing brain. The target cells for reelin express the cytoplasmic adapter protein Dab1, which binds to the reelin receptors VLDLR and ApoER2. In the present work, we have studied the localization of both receptors in developing mouse and human cortex, olfactory bulb and cerebellum. In mouse, some Cajal–Retzius cells express reelin and VLDLR; in humans, all the components of the signalling pathway (Reelin, Dab1, VLDLR and ApoER2) are present in subsets of Cajal–Retzius cells. In the mouse cortical plate, VLDLR and ApoER2 are present from E15 to postnatal stages; in human cortical plate they are most prominent at ≈ 20 gestational weeks. In mice, cerebellar Purkinje cells only express VLDLR whereas in humans they express both VLDLR and ApoER2. Mitral cells of the mouse olfactory bulb are ApoER2-positive and VLDLR-negative. In sum, the receptor expression patterns are similar in the human and mouse cortical plate but differ in Cajal–Retzius and Purkinje cells, which in humans express additional components of the reelin–Dab1 pathway.

Notes: summary  The literature has documented a controversial discussion on the possible relationship of otogenous symptoms and craniomandibular dysfunction since the 1920s. Therefore, an investigation was conducted which consisted of two parts: a case study with population-based controls and a cross-sectional study. The aim of the first study was to screen a group of patients suffering from acute or chronic tinnitus for temporomandibular disorders (TMD) in comparison with a population-based group of volunteers without tinnitus. To this end, 30 patients (13 females and 17 males, age 18–71 years) suffering from acute hearing loss associated with tinnitus, isolated acute tinnitus, and chronically transient tinnitus were examined for symptoms of craniomandibular dysfunction. The results were compared with those of clinical functional analysis from 1907 subjects selected representatively and according to age distribution from the epidemiological ‘Study of Health in Pomerania’ (SHIP); the occurrence of tinnitus was ruled out in these control subjects. Statistical analysis was performed with Chi-square and Mann–Whitney U-tests. Sixty per cent of the tinnitus patients and 36·5% of the control subjects exhibited more than two symptoms of TMD (P = 0·004). Tinnitus patients had significantly more muscle palpation pain (P 〈 0·001), temporomandibular joint (TMJ) palpation pain (P 〈 0·001), and pain upon mouth opening (P 〈 0·001) than the general population group. No statistical differences were found in TMJ sounds, limitation of mandibular movement, or hypermobility of the TMJ. Furthermore, 4228 subjects of the population group examined in the epidemiological study were screened for co-factors of tinnitus with the help of a multivariate logistic regression model which was adjusted for gender, age, and a variety of anamnestic and examined data. Increased odds ratios (OR) were found for tenderness of the masticatory muscles (OR = 1·6 for one to three painful muscles and OR = 2·53 for four or more painful muscles), TMJ tenderness to dorsal cranial compression (OR = 2·99), listlessness (OR = 2·0) and frequent headache (OR = 1·84) A relationship between tinnitus and TMD was established in both examinations. Tinnitus patients seem to suffer especially from myofascial and TMJ pain. A screening for TMD should be included in the diagnostic survey for tinnitus patients.