Objective To explore whether the changes of sound source in the horizontal azimuth can induce mismatch negativity (MMN) ,and quantify the minimal audible angle which could elicit the MMN and to find effec‐tive way to test human's ability of sound localization in the horizontal plane .Methods With the self developed sound localization device and Bio - logic auditory evoked potentiometer ,in the free field hearing tests were performed on 30 healthy young volunteers according to oddball stimulation sequence .We adopted 1 000 Hz pure tone as the stand‐ard stimuli , the change of sound source location as experimental models ,using minimum audible angle (MAA ) measure procedure ,sound localization test was conducted at 0° ,± 45° ,± 90°standard positions in the horizontal plane .MMN was obtained by subtracting the ERP of deviant stimuli from the ERP of standard stimuli .The latency and amplitude of each MMN were recorded .Results The MMAs of normal young people were recorded and normal values of latency and amplitude of MMN were obtained .The results of the sound localization test for the youth were :MAA(0°)= 2 .09 ± 1 .81° ,MAA( - 45°)= 3 .84 ± 1 .61° ,MAA (45°) = 3 .69 ± 2 .39° ,MAA ( - 90°) = 4 .41 ± 1 . 41° ,MAA(90°)= 4 .23 ± 3 .22° ,separately .There was a significant effect of the location of the deviant stimulus , with those presented at 90° eliciting larger peaks and longer latency period than those presented at 0° .Conclusion Our findings suggest that changes of sound position in the horizontal azimuth can induce mismatch negative waves , and MMN on the basis of MAA test procedure could be used to evaluate the ability of sound localization .

Objective: To explore the influencing factors for depressive symptoms in adolescents in China, so as to provide insights into promoting mental health of adolescents. Methods: The 2020 follow-up survey data of China Family Panel Studies were collected, including demographic information, lifestyle, family factors and academic factors of adolescents aged 10-19 years. Depressive symptoms were evaluated using the 8-item Center for Epidemiological Studies Depression Scale. The influencing factors for depressive symptoms in adolescents were analyzed using a multivariable logistic regression model. Results: A total of 2 777 adolescents were analyzed, including 1 470 males (52.93%) and 1 307 females (47.07%). There were 1 186 adolescents (42.71%) from urban areas and 1 591 adolescents (57.29%) from rural areas, 106 smokers (3.82%), and 459 adolescents (16.53%) with depressive symptoms. Multivariable logistic regression analysis showed that academic stress (OR=1.268, 95%CI: 1.151-1.396), poor self-rated health (OR=1.255, 95%CI: 1.116-1.411), smoking (OR=1.901, 95%CI: 1.127-3.207), low trust in parents (OR=0.780, 95%CI: 0.729-0.835) and large family size (OR=1.095, 95%CI: 1.035-1.158) were associated with an increased risk of depressive symptoms in adolescents. Conclusion The influencing factors for depressive symptoms in adolescents were academic stress, self-rated health, smoking, trust in parents and family size.

Objective To explore a method of detecting the horizontal localization ability in normal children aged 1~3 years old, and to obtain the minimum audible angle (MAA) at horizontal 0° degree in these children.Methods Using minimum audible angle measure procedure on the basis of conditioned play audiometry and behavioral audiometry methods, sound localization test at horizontal 0° degree was conducted in 37 children aged from 1 to 7 years old with stimulus of different frequencies.Results All 37 children completed the 1 000 Hz tests, 35 children completed the 500 Hz tests, and 30 children completed the 4 000 Hz test.An analysis of 30 children who completed all the tests was performed, 15 of them aged 1~3 years old and the rest aged 4~7 years old.The results for children aged 1~3 years old were as below: 1 000 Hz MAA(0°) =3.57°±1.35°,500 Hz MAA(0°) =5.03°±2.96°,and 4 000 Hz MAA(0°) =5.4°±2.86°, respectively.The results for children aged 4~7 years old were as below: 1 000 Hz MAA(0°) =3.56°±1.48°,500 Hz MAA(0°) =3.5°±2.17°,and 4 000 Hz MAA(0°) =6.13°±4.09°, respectively.There was no significant difference in MAA (0 °) at corresponding frequencies between the two groups.For the children aged 1~3 years old, there was no significant difference in MAA (0 °) among 500 Hz, 1 000 Hz and 4 000 Hz frequencies.For the children aged 4~7 years old, there was significant difference in MAA(0 °) between 500 Hz and 4 000 Hz as well as between 1 000 Hz and 4 000 Hz frequencies.However, there was no significant difference in MAA (0 °) between 500 Hz and 1 000 Hz frequencies.Conclusion MAA test procedure on the basis of conditioned behavioral audiometry and play audiometry could be used to evaluate the ability of sound localization in 1~3 years old children.The frequencies may have effects on children''s sound localization test results and there was no significant difference in MAA (0 °) between the 1~3 years old group and the 4~7 years age group.

Objective To investigate sequence variations of 12 miRNA genes in multiple myeloma(MM) in order to find whether sequence variations in miRNA genes are associated with tumorigenesis and discuss the clinical significance of MM associated with miRNA genes mutations. Methods The miRNA gene mutations in 20 cases of MM, 4 MM-derived cell lines and 20 controls were detected by the methods of polymerase chain reaction single stranded conformation polymorphism (PCR-SSCP) and silver staining technique. Both clinical features and laboratory results were analyzed simultaneously. Results The electrophoretic patterns showed a total of three variations in miR-19a, miR-19b and miRNA-335,which were observed in 3 MM cells (15 %, 3/20). We also found variations of miRNA-335 in MM-derived cell lines KM-3and RPMI8226. However, no sequence alteration in the miRNA genes was observed in our set of controls. One of the three MM patients died, and two of them were detected mutations at the terminal stage of the disease.Conclusion A relative high frequency of miRNA gene mutation was found in MM and MM derived cell lines, which suggests possibility of a main mechanism underlying tumorigenesis. And, detecting miRNA gene mutations in MM might be benefit to evaluate the progression and prognosis of disease.

Objective To identify the characteristics of hippocampal 3-dimensional MRI in patients diagnosed as having subtypes of amnestic mild cognitive impairment(aMCI)using hippocampal surfacebased analytic technique.Methods Fifry aMCI patients and 16 healthy controls who were equivalent in age and education(NC)were recruited.Every subiect carried out a 3-dimensional MRI scan.After the imaging data were acquired.the borders of the hippocampus were manually traced in coronal vlew using the software of InsightSNAP1.4.1. Hippocampal volume was computed automatically and statistically analysed.Hippocampal 3-dimension MRI were transformed into 3-dimension parametric surface mesh models of 400×200 prids.Hippocampal radial distance measures which was the distance from the surface point to the central axis were statistically compared between two groups.The radial atrophy significance maps were acquired and adjusted for multiple comparisons.Hippocampal morphological difference maps of aMCI in contrast with NC were acquired.Results The average normalized volume of left hippocampus were(3247.5±600.2)mm3 in aMCI patients and(3467.9±451.3)mm3 in NC subjects.The average normalized volume of right hippocampus were(3416.8±699.1)mm3 in aMCI patients and(3469.1±358.9)mm3 in NC subjects.Comparison of hippocampal volume did not differ significantly between aMCI patients and NC subjects(t=1.161,P=0.255;U=0.178,P=0.859).By using hippocampal surface-based morphologic analytic technique,3-dimension hippocampal morphological difference maps between two groups were acquired,showing significant atrophy on the lateral and inferior hippocampal surface which corresponded to CA1 and subiculum hippocampal subfields bilaterally in aMCI patients compared with NC subjects. Conclusions aMCI patients do not have significant volume loss in the hippocampus. Through hippocampal surface-based morphologic analyses, partial regional atrophy of hippocampus at some degree is found, mainly localizing in the lateral and inferior hippocampal regions which correspond to CA1 and subiculum hippocampal subfields bilaterally in aMCI compared with NC. These results may reflect the early image marker in aMCI.

ObjectiveTo investigate the characteristics of spontaneous activities throughout the whole brain with Alzheimer's disease (AD) by resting state functional magnetic resonance imaging ( fMRI ).Methods The subjects included 23 AD patients and 21 normal controls (NC),who underwent a neuropsychological test battery including MMSE and Auditory Verbal Learning Test (AVLT) and restingstate fMRI using GE Signa 3.0 T MR scanner.The neuropsychological scores were compared between two groups.Regional homogeneity (ReHo) method was used to explore the different regional spontaneous activities throughout the brain between normal controls and patients with AD.Results In AD group,clinical variables (MMSE scores:20 ±4,AVLT-Immediate Recall:2.6 ± 1.6,AVLT-Delay Recall:0.4 ±0.7,AVLT-Recognition:5.8 ± 3.7 ) were lower than NC group( 29 ± 1,5.9 ± 1.2,5.5 ± 2.0,9.2 ± 1.1,T =10.58,7.21,10.99,3.96,all P ＜ 0.01 ).With the threshold of P ＜ 0.01 for each voxel and a cluster size of at least 100 voxels,decreased ReHo indexes were found in default mode network (DMN) including the medial prefrontal cortex,posterior cingulate gyrus/precuneus,right superior temporal gyrus and bilateral superior parietal lobule/inferior parietal lobule in AD,while increased ReHo indexes were found in left putamen and thalamus compared with controls.ConclusionThe DMN are damaged in AD and spontaneous activities of putamen and thalamus are reinforced as compensation response of subcortical structures.

Objective To study the functional connectivity (FC) pattern of thalamus in patients with Alzheimer' s disease (AD).Methods In the present study,resting state functional magnetic resonance imaging (MRI) data were obtained from 30 patients with AD and 26 subjects with normal cognition (NC).The altered functional connectivity pattern in AD was evaluated by comparing to NC.Then a correlation analysis was performed between the strength of FC of the identified regions and various clinical variables for evaluating the relationships between the strength of FC and the cognitive abilities (MMSE,immediate recall and delayed recall of Auditory Verbal Learning Test) of the AD patients.Results The MMSE(19.7 ± 4.1),immediate recall (2.8 ± 1.7) and delayed recall (0.7 ± 1.3) of Auditory Verbal Learning Test in AD patients were lower than NC group (28.8 ± 1.0,5.9 ± 1.2,5.7 ± 2.2 ; t =11.09,8.09,10.51,all P ＜0.05).Compared to NC,AD patients showed decreased FC between the left thalamus and several regions of brain including right posterior/middle cingulate cortex (PCC/MCC.R),left medial prefrontal cortex (MPFC.L) and right superior frontal gyms/medial prefrontal cortex (SFG/MPFC.R).For the right thalamus,decreased FC was found in SFG/MPFC.R,PCC/MCC.R and right hippocampus.We also found increased FC between the bilateral thalamus and many regions of brain including inferior temporal gyrus,medial temporal gyrus,SFG,postcentral gyrus,paracentral lobule,inferior frontal gyms and insula.Significant correlations between the fitted FC strength and clinical variables were also detected.Conclusions FC pattern of thalamus in AD group is impaired.Increased FC in AD may indicate the presence of a compensatory mechanism.The alteration is related with cognitive function in AD.

ObjectiveTo optimize the b-value of breast diffusion-weighted MRI (DW-MRI) at 1.5T by applying a range of b values and comparing the apparent diffusion coefficient (ADC) and signal-to-noise ratio (SNR) on a phantom,disease-free breast tissues,and benign and malignant lesions.Methods A phantom and 32 women with pathologically confirmed malignant ( 18 ) and benign ( 14 ) lesions were examined using EPI-DWI with different b values on a 1.5 T MR scanner.The b-value of EPI-DWI was 0,50,100,200,400,600,800,1000,1200,1400,1600,1800,2000,2200,2400,and 2600 s/mm2,respectively.The SNR and ADC values of the phantom,disease-free breast tissues,and benign and malignant lesions were measured.The correlation between the b-value and ADC or SNR of each image was analyzed.ResultsThe SNR of DWIdecreased as the b-valueincreased,showing aninversecorrelation (r =-0.802,P ＜0.01 ).The ADC values of benign and malignant lesion decreased as the b-value increased (r =-0.923 and -0.855,P ＜0.01 ).The maximum difference in ADC between malignant and benign lesions was observed when the b-value is between 800 and 1000 s/mm2 and diminished when the b-value was greater than 1400 s/mm2.ConclusionFor good image quality and valid differentiation between malignant and benign lesions,the optimized b-value of DWI at 1.5 T is between 800 s/mm2 and 1000 s/mm2.

Objectives To measure the microstructural differences in the brains of participants with amnestic mild cognitive impairment ( aMCI) and compare with a control group using a magnetic resonance diffusion tensor imaging ( DTI) technique with fully automated image analysis tools. Methods A standardized clinical and neuropsychological evaluation was conducted on each subject 31 participants (15 participants with aMCI, 16 healthy elderly adults) underwent magnetic resonance imaging (MRI)-based DTI. To control the effects of anatomical variation, the diffusion images of all participants were registered to standard anatomical space. Voxel-by-voxel comparisons showed significant regional reductions in white matter regions of fractional anisotropy (FA) in the participants with aMCI as compared with the controls. Results Significantly decreased FA value measurements (P<0. 001) were observed in the right frontal white matter in participants with aMCI. Moreover, there was a statistically significant difference between the patients with aMCI and controls in considering the small regions of bilateral superior frontal gyrus white matter (P < 0.001). Conclusions White matter damage of frontal lobe may play an important role in histopathologic changes associated with amnestic mild cognitive impairment

0.05). CONCLUSION The sound localization apparatus can test the localization ability of person, and it can be used in simply and reasonably.