Objective:This study investigates the effect of signal-to-noise ratio (SNR), frequency, and bandwidth on horizontal sound localization accuracy in normal-hearing young adults.Methods:From August 2022 to December 2022, a total of 20 normal-hearing young adults, including 7 males and 13 females, with an age range of 20 to 35 years and a mean age of 25.4 years, were selected to participate in horizontal azimuth recognition tests under both quiet and noisy conditions. Six narrowband filtered noise stimuli were used with central frequencies (CF) of 250, 2 000, and 4 000 Hz and bandwidths of 1/6 and 1 octave. Continuous broadband white noise was used as the background masker, and the signal-to-noise ratio (SNR) was 0, -3, and -12 dB. The root-mean-square error (RMS error) was used to measure sound localization accuracy, with smaller values indicating higher accuracy. Friedman test was used to compare the effects of SNR and CF on sound localization accuracy, and Wilcoxon signed-rank test was used to compare the impact of the two bandwidths on sound localization accuracy in noise.Results:In a quiet environment, the RMS error in horizontal azimuth in normal-hearing young adults ranged from 4.3 to 8.1 degrees. Sound localization accuracy decreased with decreasing SNR: at 0 dB SNR (range: 5.3-12.9 degrees), the difference from the quiet condition was not significant ( P>0.05); however, at -3 dB (range: 7.3-16.8 degrees) and -12 dB SNR (range: 9.4-41.2 degrees), sound localization accuracy significantly decreased compared to the quiet condition (all P<0.01). Under noisy conditions, there were differences in sound localization accuracy among stimuli with different frequencies and bandwidths, with higher frequencies performing the worst, followed by middle frequencies, and lower frequencies performing the best, with significant differences (all P<0.01). Sound localization accuracy for 1/6 octave stimuli was more susceptible to noise interference than 1 octave stimuli (all P<0.01). Conclusions:The ability of normal-hearing young adults to localize sound in the horizontal plane in the presence of noise is influenced by SNR, CF, and bandwidth. Noise with SNRs of ≥-3 dB can lead to decreased accuracy in narrowband sound localization. Higher CF signals and narrower bandwidths are more susceptible to noise interference.

Objective:To evaluate auditory spatial discrimination capabilities in patients with mild to moderately severe symmetrical sensorineural hearing loss (SNHL) and to compare the impact of different psychophysical testing methods on Minimum Audible Angle (MAA) and test duration.Methods:A total of 105 symmetrical SNHL patients aged from 18 to 60 years old were enrolled from April to July 2023, including 56 males and 49 females. They were divided into three groups based on PTA: mild, moderate, and moderately severe hearing loss, with 35 individuals in each group. Additionally, a control group of 35 individuals with normal hearing was tested, including 18 males and 17 females. Participants underwent four distinct psychophysical discrimination tests: the block up-down, 1-up/1-down, 1-up/2-down, and 1-up/3-down procedures. We recorded the MAA and test duration for each. We employed repeated measures of ANOVA to compare the MAA and test duration across different methods and groups, and Pearson′s correlation to assess the relationship between MAA and degree of hearing loss.Results:MAA of sound localization in patients with symmetrical SNHL was significantly positively correlated with the degree of hearing loss ( r=0.59, P<0.01). Significant deterioration in MAA was observed as hearing loss progressed to the moderate level (PTA≥35 dBHL, P<0.01). The testing methods significantly influenced MAA and testing duration ( F=24.02, P<0.01; F=75.56, P<0.01) and the 1-up/1-down method was the quickest, averaging only (0.69±0.32) mins. Conclusions:The horizontal plane auditory spatial discrimination abilities in patients with symmetrical SNHL is impaired progressively with increasing hearing loss, notably beyond moderate hearing loss levels. Different psychophysical methods influence both MAA and test duration, the quicker 1-up/1-down method is recommended for assessing MAA in symmetrical SNHL patients.

As a non-essential metal, cadmium (Cd) pollution poses severe threats to plant growth, environment, and human health. Phytoextraction using nursery stocks prior to their transplantation is a potential useful approach for bioremediation of Cd contaminated soil. A greenhouse pot experiment was performed to investigate the growth, Cd accumulation, profiles of transcriptome as well as root-associated microbiomes of Photinia frase in Cd-added soil, upon inoculation of two types of arbuscular mycorrhizal fungi (AMF) Sieverdingia tortuosa and Funneliformis mosseae. Compared with the control, inoculation of F. mosseae increased Cd concentrations in root, stem and leaf by 57.2%, 44.1% and 71.1%, respectively, contributing to a total Cd content of 182 μg/plant. KEGG pathway analysis revealed that hundreds of genes involved in 'Mitogen-activated protein kinase (MAPK) signaling pathway', 'plant hormone signal transduction', 'biosynthesis of secondary metabolites' and 'glycolysis/gluconeogenesis' were enriched upon inoculation of F. mosseae. The relative abundance of Acidobacteria was increased upon inoculation of S. tortuosa, while Chloroflexi and Patescibacteria were increased upon inoculation of F. mosseae, and the abundance of Glomerales increased from 23.0% to above 70%. Correlation analysis indicated that ethylene-responsive transcription factor, alpha-aminoadipic semialdehyde synthase, isoamylase and agmatine deiminase related genes were negatively associated with the relative abundance of Glomerales operational taxonomic units (OTUs) upon inoculation of F. mosseae. In addition, plant cysteine oxidase, heat shock protein, cinnamoyl-CoA reductase and abscisic acid receptor related genes were positively associated with the relative abundance of Patescibacteria OTUs upon inoculation of F. mosseae. These finding suggested that AMF can enhance P. frase Cd uptake by modulating plant gene expression and altering the structure of the soil microbial community. This study provides a theoretical basis for better understanding the relationship between root-associated microbiomes and root transcriptomes of P. frase, from which a cost-effective and environment-friendly strategy for phytoextraction of Cd in Cd-polluted soil might be developed.
Cadmium ; Humans ; Microbiota ; Mycorrhizae ; Photinia ; Soil Pollutants ; Transcriptome

Gram-negative bacteria have become the main pathogens and cause serious clinical problems with increased morbidity and mortality. However, the slow discovery of new antimicrobial agents is unable to meet the need for the treatment of bacterial infections caused by drug-resistant strains. The interaction of L12 and L10 is essential for ribosomal function and protein synthesis. In this study, a yeast two-hybrid system was established to successfully detect the interaction between L12 and L10 proteins from gram-negative bacteria , which allows us to screen compounds that specifically disrupt this interaction. With this system, we identified two compounds IMB-84 and IMB-87 that block L12-L10 interaction and show bactericidal activity against . We used glutathione--transferase (GST) pull-down and surface plasmon resonance (SPR) assays to demonstrate that these compounds disrupt L12-L10 interaction and the target of compounds was further confirmed by the overexpression of target proteins. Moreover, protein synthesis and elongation factor G-dependent GTPase activities are inhibited by two compounds. Therefore, we have identified two antibacterial agents that disrupt L12-L10 interaction by using yeast two-hybrid system.

Objective To investigate the effects of aging on the brain stem speech encoding in spontaneous post-menopause women.Methods There were twenty post-menopause women with normal hearing for test and twenty ovariectomized women with normal hearing for contrast.Speech-evoked auditory brainstem response (speech-ABR) was used.The speech syllable /da/ as stimulus sound was transmitted to right ear by the insert earphones in speech-ABR test.Results Response waves of speech-ABR in ovariectomized women were similar to those in post-menopause women, which contained the onset response (peak V and A), the transition (peak C), the frequency following responses (peak D, E and F) and the offset response (peak O).The characteristics of speech-ABR's peak latency and magnitude were similar between the two groups.Except that the bilateral ovariectomized women had a shorter latency of waves O for the transient response (P<0.01), the larger amplitude of peak F for the periodic portion than post-menopause women (P<0.05).No significant differences were found in the amplitude the latency of the other waves, and V/A slope between bilateral ovariectomized women (0.21±0.10 μV /ms)and post-menopause women (-0.20±0.09 μV/ms) was similar and had no statistical significance (P>0.05).After the combination of ovariectomized women and post-menopause women, the age of these subjects was positively correlated with the latency of O wave (P<0.05).Others had no correlation with age in the amplitude and latency of the waves of speech-ABR.Conclusion Aging does not affect on brain stem speech encoding in spontaneous post-menopause women.

Objective To investigate the correlation between reproductive hormone concentration and the amplitude and latency of speech-evoked auditory brainstem response (speech-ABR) in young adults, and to explore the effects of reproductive hormone on the speech processing ability of young people.Methods Speech-ABR of thirty five normal hearing young adults, including seventeen females (27.29±1.83 years old) and eighteen males (28.17±2.50 years old) were recorded.The speech syllable /da/ was transmitted as a stimulus sound to the right ears through insert earphones in speech-ABR test.All participants had air conduction hearing thresholds of 20 dB HL or better across the standard audiometric frequencies (250~8 000 Hz) in both ears, and click-ABRs were also within normal limits.At the same time, the concentrations of estradiol and testosterone in the serum were examined.Results ① Females had a shorter latency than males in transient responses (waves V, A and O) and sustained responses (waves D, E and F) of speech-ABR (P<0.05, respectively).The amplitude of transient response (waves V and A) and sustained response (waves D, E and F) in females was also significantly larger than that in males (P<0.05, respectively), except for amplitude of peak O (P>0.05).The V/A slope in females was significantly steeper than that in males (P<0.05).② Estradiol levels in females (118.77±102.66 pg/ml) were significantly higher than that in males (52.91±14.77 pg/ml) (P<0.05), and the total testosterone concentration in females (457.65±140.82 pg/ml) was significantly lower than that in males (3 677.37±1 155.80 pg/ml) (P<0.05).③ A correlation analysis between speech-ABR and estradiol or total testosterone showed that all peak latencies of speech-ABR in transient responses (waves V, A and O) and sustained responses (waves D, E and F) were negatively correlated with the estradiol concentration (P<0.05 respectively), in which the correlation coefficient was between 0.2~0.4.All peak latencies of speech-ABR were positively correlated with the total testosterone concentration (P<0.05 respectively), in which the correlation coefficient was between 0.4~0.7.④ The amplitudes of speech-ABR increased with estradiol concentration growing, the wave V and estradiol concentrations were positively correlated (P<0.05).The estradiol concentrations showed a significant negative correlation with wave A, D, E, F and O wave (P<0.05 respectively), with a correlation coefficient between 0.2~0.7.On the contrary, the amplitudes of speech-ABR decreased with the increasing of total testosterone concentration, and the wave V, wave A, V/A slope and total testosterone concentration were moderately correlated (P<0.05),with a correlation coefficient between 0.4-0.6.The correlation between the amplitudes of D wave and total testosterone concentration was not statistically significant (P>0.05), and the correlation between wave E and wave F and total testosterone concentration was weakly correlated (P<0.05).In addition, the amplitudes of the wave O were also independent with testosterone levels (r=0.133, P>0.05).Conclusion There are correlations between the level of reproductive hormone and the amplitude and latency of speech-ABR.It is one of the reasons for the gender difference in the brainstem speech coding ability of normal young adult.

Objective To investigate the relationship between benign paroxysmal positional dizziness (BPPV) and cerebrovascular disease and to promotethe practice of evidence bases medicinein thediagnosis,treatment and recurrenceprevention of BPPV in the elderly.Methods A total of 80 elderly patients were consecutively recruited from the Dizziness Outpatient Clinic from January 2013 to June,2014,with 80 non-BPPV elderly individuals receiving routine physical checkups during the same period serving as the control group.Clinical characteristics,lab test results and imaging data were compared between the two groups.Single factor and multivariate logistic regression analyses were conducted to identify independent risk factors for BPPV in the elderly.Results The experimental group showed higher rates of lacunar infarction,leukoaraiosis and intracranial artery stenosis than the control group(x2 =10.180,4.606 and 3.956,respectively;P=0.001,0.032 and 0.047,respectively).The prevalences of hyperlipidemia and type 2 diabetes were higher in the BPPV group than in the control group(x2 5.013 and 6.041,respectively;P=0.025 and 0.014,respectively).Differences in number of carotid atherosclerotic plaque cases,total cholesterol,triglyceride,homocysteine and uric were found between the two groups (x2 =11.237,t=2.862,2.230 and 4.270,respectively;P=0.001,0.005,0.027 and 0.000,respectively).Multivariate logistic regression analysisfound that blood uric acid,hyperglycemia,type 2 diabetes and hypertension were independent risk factors for BPPV (OR=1.006,7.104,3.152 and 3.273,respectively;P=0.005,0.000,0.004 and 0.002,respectively).The existence of carotid atherosclerotic plaques also increased the risk of BPPV (OR =384.570,95 ％ CI:46.935～ 3151.055,P =0.000).Conclusions BPPV in the elderlyis closely associated with cerebrovascular disease and its risk factors.Therefore,it is of great clinical significance to assess cerebrovascular function and carotid atherosclerotic plaque development for improved prognosis and effective prevention of recurrence of BPPV in the elderly.

Objective The aim of this study was to compare the basic characters of the speech - evoked audi‐tory brainstem response (speech - ABR) in healthy young women with that in post - menopause women and to get the changes of the probable factors for the auditory brainstem pathway encoding of speech sounds in healthy post -menopause women .Methods Speech - ABR of forty - seven normal hearing subjects including twenty - seven young women and twenty post - menopause women were recorded .The speech syllable /da/ as stimulus sound was trans‐mited to right ear by the insert earphones in speech - ABR test .Results The response waves of speech - ABR in post - menopause women were similar to those in young women ,which containal the onset responses (peak V and A) ,the transition (peak C) ,the frequency following responses (peak D ,E and F) and the offset response (peak O) .Except wave C ,the latency of wave V (6 .99 ± 0 .34ms) ,wave A (8 .32 ± 0 .49 ms) and wave O (48 .86 ± 0 .50 ms) in post - menopause women were evidently longer than those of in young women (the waveV :6 .60 ± 0 .25 ms ,wave A :7 .56 ± 0 .31 ms and wave O :47 .88 ± 0 .31 ms) ,while the amplitude of wave A ( - 0 .16 ± 0 .06 μV ) and O ( - 0 .12 ± 0 .06 μV ) in post - menopause women were obviously lower (modulus) than those of in young women (the wave A : - 0 .27 ± 0 .08 μV and O : - 0 .18 ± 0 .07 μV)(P< 0 .05) .In the FFR of speech - ABR ,the latency of wave D (23 .27 ± 0 .67 ms) ,wave E (31 .88 ± 0 .58 ms) and F (40 .61 ± 1 .22 ms) in post - menopause women were also longer than those of in young women (the wave D :22 .40 ± 0 .44 ms ,wave E :31 .00 ± 0 .43 ms and F :39 .53 ± 0 .61 ms) .Besides ,the amplitudes of wave D ( - 0 .12 ± 0 .04 μV ) and F ( - 0 .08 ± 0 .06 μV ) in post -menopause women were visibly lower (modulus) than those of in young women (the wave D : - 0 .17 ± 0 .08 μV and F : - 0 .16 ± 0 .07 μV)(P< 0 .05) . ④ The V /A slope also showed very significant difference ,the V/A slope in young women was much bigger than that in post - menopause women (P< 0 .05) .Conclusion The synchronism and phase locking of auditory brainstem pathway to processing and encoding capability in healthy post - menopause women is poorer than those of in young women .It may suggest that the growth of the age and the decrease of hor‐mone will weaken the ability to processing of speech sounds in women .

AIM:To investigate the effect of oleuropein on interleukin-1β( IL-1β)-induced SD rat articular chondrocytes .METHODS:The SD rat articular chondrocytes were isolated by 2 step enzyme digestions .The chondrocytes were cultured in vitro.Inverted microscopic observation was performed during the culture .Alcian blue staining and type II collagen immunohistochemical staining were used to identify the chondrocytes .The effects of oleuropein on the viability of chondrocytes were determined by CCK-8 assay.The cells in 3rd passage were pretreated with oleuropein at 10, 50 or 100 μmol/L and subsequently stimulated with IL-1βat 10 μg/L for 24 h.Production of prostaglandin E 2 ( PGE2 ) and ni-tric oxide (NO) were evaluated by the Griess reaction and an enzyme linked immunosorbent assay (ELISA).The mRNA expression of matrix metalloproteinase ( MMP)-1 and MMP-13 was measured by real-time PCR.The protein levels of in-ducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and nuclear factor-kappa B (NF-κB) were detected by Western blotting .RESULTS:The cell viability of chondrocytes was not significantly impaired by treating with oleuropein at concentration of 10, 50 or 100μmol/L for 24 h compared with control group .Pretreatment with oleuropein significantly in-hibited the production of PGE 2 and NO induced by IL-1β.Oleuropein also significantly decreased the IL-1β-stimulated MMP-1 and MMP-13 mRNA expression in articular chondrocytes .Pretreatment with oleuropein inhibited the IL-1β-media-ted activation of NF-κB by suppressing the degradation of its inhibitory protein IκBαin the cytoplasm .CONCLUSION:Oleuropein inhibits IL-1β-induced inflammatory gene expression by suppressing NF-κB activation at the transcriptional le-vel, suggesting a new mechanism for the anti-inflammatory effects of oleuropein as a novel agent on treating with osteoarthri-tis.

Objective To assess the value of magnetic resonance imaging (MRI) T2 mapping in quantitative evaluation of cartilage repair following matrix-associated autologous chondrocyte transplantation (MACT). Methods Six patients (with 9 plug cartilages) following MACT underwent MRI on a 3.0 Tesla MR scan system at 3, 6 and 12 months after the surgery. The full-thickness and zonal areas (deep and superficial layers) T2 values were calculated for the repaired cartilage and control cartilage. Results The mean T2 values of the repaired cartilage after MACT were significantly higher than that of the control cartilages at 3 and 6 months (P<0.05), but not at 12 months (P=0.063). At 6 and 12 months, the T2 values of the superficial layers were significantly higher than those of the deep layers in the repaired cartilages (P<0.05). The zonal (deep and superficial layers) T2 values of the repaired cartilages decreased significantly over time at 6 and 12 months as compared to those at 3 months after the surgery (P<0.05). Conclusion MRI T2 mapping can serve as an important modality for assessing the repair of the articular cartilage following MACT.