Effect of subject state on auditory brainstem response threshold using Kalman-weighted averaging.

OBJECTIVES: This study aims to explore the impact of a subject's testing state on auditory brainstem response (ABR) thresholds using a novel ABR system (Vivosonic Integrity™), which incorporates Kalman-weighted averaging and bluetooth electrical isolation to address the limitation of conventional ABR limitation to obtain a stable result under non-sedated conditions, especially for infants and children. METHOD: Twenty-four adults (18-34 years old, 48 ears) with normal hearing were enrolled for ABR testing under three different states (lying quietly in the supine position or sleeping-lying; watching silent videos quietly in a seated position-sitting; and writing in a seated position-writing), which simulate the behaviors of young children most often encountered during non-sedated Kalman-weighted ABR testing in clinical practice. The click ABR (cABR) and tone-burst ABR (tbABR) thresholds (0.5, 1, 2, and 4 kHz) of each subject and the time taken to reach the monaural threshold for each kind of stimulus were recorded. RESULTS: (1) The cABR and tbABR thresholds were observed to increase in the following order: lying < sitting < writing. Significant threshold differences were found between any two states, except for between the sitting and lying states for the cABR and between sitting and writing for the 0.5 kHz tbABR. (2) The time required for cABR testing in the writing state was significantly longer than that in the lying and sitting states. The time required for 1 and 4 kHz tbABR testing in the lying state was significantly shorter than that in the sitting or writing state. For 2 KHz tbABR, only testing time under writing was significantly longer than that under lying. There were no significant differences in the time used for 0.5 kHz tbABR testing among different states. CONCLUSIONS: Different testing states have significant impacts on the thresholds of ABRs using Kalman-weighted averaging. A subject's state during ABR testing warrants consideration, and normal levels and correction values to estimate the hearing threshold from the ABR threshold should be determined for different testing states.

In vitro and in vivo relaxation and anti-inflammation of natural flavonoids from Elaeagnus pungens leaf via L-type calcium channel and targeting MAPK signal pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: In traditional Chinese medicine (TCM), the leaf of Elaeagnus pungens Thunb. (Family Elaeagnaceae) is a herb documented as an antiasthmatic remedy to treat the severe asthma, bronchitis and other respiratory diseases in the early material medica "Bencao Gangmu" (Ming dynasty, about 442 years ago). AIM OF THE STUDY: This work is purposed to investigate the pharmacological effects and mechanism of total flavonoids from Elaeagnus pungens leaves (FLA) on asthma in vivo and vitro. MATERIALS AND METHODS: Female BALB/c mice were sensitized by intraperitoneal injection of OVA with aluminum hydroxide and intranasal challenged with OVA. After treatment with FLA (10, 20 mg/kg p.o.), the behaviors of mice were observed by score evaluation. Enumeration of total cells and OVA-specific IgE assay in the blood were measured as well as enumeration of total cells and cytokines assay in the BALF. Furthermore, histopathological analysis was performed by HE staining. The in vitro relaxing action on muscle force of FLA (0.0316-10.0 mg/ml) was evaluated using isometric tension in tracheal rings, and VDLCC currents were recorded to explore the relaxation mechanism in the isolated tracheal rings and mouse ASM cells, respectively. In vitro anti-inflammatory actions were assessed with LPS-stimulated RAW 264.7 macrophages. The production of inflammatory mediators and MAPK signaling pathway was estimated using ELISA and Western blotting analysis, respectively. RESULTS: The high dose of flavones from E. pungens leaf (20 mg/kg) can significantly improve the symptom of asthma breakout and relieve the lung swelling. FLA treatment decreased eosinophils and leukocytes numbers in blood and BLAF with a dosedependent manner. Furthermore, the inhibiting effect of FLA on the level of Ig E and inflammatory-related cytokines including TNF-α, IL-5 showed dose-independent. FLA relaxed high K + -induced contraction in a dose-dependent manner. The maximal relaxation produced by FLA was 99.7% (IC 50 = 0.46 mg/ml). The whole-cell VDLCC currents were abolished by FLA (3.16 mg/ml) and FLA significantly decreased the maximal amplitude of VDLCCs. No cytotoxic effect of FLA was observed in RAW264.7 cells under the tested concentrations (1-300 µg/mL). The increased IL-6 and NO by the stimulation of LPS in RAW264.7 cells were significantly inhibited by FLA in the dosedependent manner. Treatment with LPS in the presence of FLA, LPS-induced phosphorylation of ERK1/2 and JNK was inhibited in the macrophages. CONCLUSION: FLA from Elaeagnus pungens leaf can alleviate the inflammation symptom via reducing the eosinophils and leukocytes numbers as well as the production of pro-inflammatory cytokines. This anti-inflammatory effect is related to the modulation of the MAPK signaling pathway. FLA can relax the precontracted TRs by blocking the VDLCCs, which interrupts extracellular Ca 2+ influx and inhibit the rise of [Ca 2+ ]i. It strongly suggests that these flavonoids components are the substances basis of Elaeagnus pungens leaves for allergic action, bronchospasm and inflammation in asthma.

In Vivo Evaluation of the Antiasthmatic, Antitussive, and Expectorant Activities and Chemical Components of Three Elaeagnus Leaves.

The leaf of Elaeagnus lanceolata and Elaeagnus henryi as well as Elaeagnus pungens has been documented as an effective herb for the treatment of asthma and chronic bronchitis in traditional clinical medicine. This study was aimed at evaluating the antiasthmatic, antitussive, and expectorant activities of the water extracts from the three plants in vivo and analyzing their chemical components by HPLC-DAD. At the medium and high doses, the water extracts of three Elaeagnus leaves significantly prolonged the preconvulsive time (P < 0.01) in guinea pigs, lengthened the latent period of cough (P < 0.01) and decreased the cough frequency caused by aqueous ammonia in mice (P < 0.01), and enhanced tracheal phenol red output in mice (P < 0.01). There were no significant differences in the pharmacological actions between the three Elaeagnus leaves. Moreover, there was more similarity on overlap peaks in the range of retention time from 10 to 40 min by HPLC and many peaks that belonged to flavonoids compounds. It suggested that the main constituents of the three Elaeagnus leaves were flavonoid for the pharmacological activities. These effects were the important evidence for the traditional use of E. henryi leaf and E. lanceolata leaf as well as E. pungens to treat asthma and chronic bronchitis.

[Comparison of tone burst evoked auditory brainstem responses with different filter settings for referral infants after hearing screening].

OBJECTIVE: Auditory brainstem responses (ABR) evoked by tone burst is an important method of hearing assessment in referral infants after hearing screening. The present study was to compare the thresholds of tone burst ABR with filter settings of 30 - 1500 Hz and 30 - 3000 Hz at each frequency, figure out the characteristics of ABR thresholds with the two filter settings and the effect of the waveform judgement, so as to select a more optimal frequency specific ABR test parameter. METHODS: Thresholds with filter settings of 30 - 1500 Hz and 30 - 3000 Hz in children aged 2 - 33 months were recorded by click, tone burst ABR. A total of 18 patients (8 male/10 female), 22 ears were included. RESULTS: The thresholds of tone burst ABR with filter settings of 30 - 3000 Hz were higher than that with filter settings of 30 - 1500 Hz. Significant difference was detected for that at 0.5 kHz and 2.0 kHz (t values were 2.238 and 2.217, P < 0.05), no significant difference between the two filter settings was detected at the rest frequencies tone evoked ABR thresholds. The waveform of ABR with filter settings of 30 - 1500 Hz was smoother than that with filter settings of 30 - 3000 Hz at the same stimulus intensity. Response curve of the latter appeared jagged small interfering wave. CONCLUSIONS: The filter setting of 30 - 1500 Hz may be a more optimal parameter of frequency specific ABR to improve the accuracy of frequency specificity ABR for infants' hearing assessment.