Langerhans' cell histiocytosis of the temporal bone: A case report.

Langerhansmporal histiocytosis (LCH) refers to a group of diseases that are characterized by the primary pathogenesis of an abnormal polyclonal proliferation of Langerhans cells that affect different structures of the human body, including the temporal bone. Thus far, the etiology of LCH remains unclear. Diagnosis of LCH is based on a synthetic analysis of the clinical presentations, as well as on features of imaging and histopathology. The clinical features, diagnosis, treatment and prognosis of LCH remain obscure, and temporal LCH is often confused with ear inflammatory lesions and malignant tumors. There are several therapeutic modalities for temporal bone LCH that include surgery, chemotherapy, radiotherapy and steroidal injections. The present study reports the case of an infant presenting a 1-month history of worsening left facial paralysis and a slowly enlarging post auricular mass followed by a 1-month history of postauricular swelling in the left ear. Computed tomography demonstrated a large mass of organized tissue. Moreover, the diagnosis of LCH was confirmed by histopathological and immunohistochemical examinations. The patient also suffered from multiple organ failure, including the liver, kidney, lymphatic system, skin, hematopoietic system and lungs. Following surgical intervention with mastoidotympanectomy, the parents of the patient refused further chemotherapy, and the patient succumbed to the disease ~6 months later.

[Bilateral versus unilateral sudden sensorineural hearing loss].

OBJECTIVE: To analyze the clinical characteristics and treatment effect between bilateral (bi-) and unilateral (uni-) sudden sensorineural hearing loss (SSNHL). METHOD: Four hundred and eighty cases of SSNHL were retrospective study, which were divided into two groups of bi-SSNHL (n = 40) and uni-SSNHL (n = 440). Clinical characteristics and treatment effects were compared of the two groups. RESULT: The incidence rate of bi-SSNHL was 8.3 percent and uni-SSNHL was 91.7 percent of all patients with SSNHL. Bi-SSNHL occurs more commonly in patients of old age, diabetes mellitus, and lipid panes abnormalities compared to uni-SSNHL. Twenty-eight ears in the bi-SSNHL group showed hearing recovery (35%), compared with 56.4 percent of patients with uni-SSNHL. CONCLUSION: Bi-SSNHL and uni-SSNHL may have a completely different clinical characteristics and treatment effect, that implies a different pathophysiology and prognosis. Recognition their different clinical characteristics and treatment effect between bilateral and unilateral SSNHL can help in counseling and managing the patients and correctly evaluate the prognosis.

FMRFamide modulates outward potassium currents in mouse olfactory sensory neurons.

1. The olfactory system can detect the presence of low concentrations of odourant molecules and discriminate even slight differences among molecules with a very similar chemical structure. The detection and discrimination of odourants are correlated with the electrophysiology of the olfactory sensory neurons. To get a better understanding of the molecular mechanisms of olfactory transduction, it is therefore of considerable importance to obtain electrophysiological recordings of olfactory sensory neurons. FMRFamide (Phe-Met-Arg-Phe-NH(2)), secreted from the nerve terminals of the nasal cavity, has been suggested to act as a neurotransmitter or neuromodulator, playing an important role in modulating the activity of olfactory receptor neurons. Its effects on voltage-dependent potassium currents in the mouse olfactory sensory neurons were investigated in the present study using the whole-cell patch-clamp technique. 2. Olfactory sensory neurons were isolated from the Kunming Mouse (KM) mouse olfactory epithelium. Different protocols were applied to obtain delayed-rectifier potassium current (I(K)) and fast transient potassium current (I(A)). The effects of FMRFamide on the outward potassium currents, including I(K) and I(A), in mouse olfactory sensory neurons were investigated. 3. We found that FMRFamide (5 micromol/L) increased the magnitude of I(K). However no effect on I(A) was observed. The activation dynamics of both currents were not changed by FMRFamide. 4. In conclusion, FMRFamide may play a role in the modulation of peripheral olfactory signals by regulating I(K). This modulation may shorten the phase of the fast repolarization of the action potential in mouse olfactory sensory neurons and increase the excitability of the neuronal membrane.