[Horizontal sound localization in presence of noise in normal-hearing young adults].

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.

[Clinical analysis of chronic rhinosinusitis in the different age group patients].

Objective:To investigate the clinical materials of chronic rhinosinusitis (CRS) in the different age group patients and explore its clinical characteristics and prognosis.Method:A retrospective analysis was carried out in 395 CRS patients with surgical treatment in our hospital in the past three years. They were divided into the young group (18 to 39 years old ), the middle-aged group (40 to 59 years old ), and the old group (over 60 years old). The clinical symptoms, accompanying diseases and prognosis in CRS patients were analyzed.Result:Among the presenting symptoms,facial pain and rhinorrhea were most common in the young group (P< 0.05), while dysosmia was most common in the old group (P< 0.05). Allergy was more prevalent in the young group and the middle-aged group than the old group (P< 0.05). CRS without polyposis was the most common diagnosis in the young group and CRS with polyposis was the more common diagnosis in the middle-aged group and the old group (P< 0.05). Patients in the young group got higher rate of improvement in olfactory function while patients in the old group got higher rate of improvement in rhinorrhea following FESS (P< 0.05).Conclusion:CRS in different age groups had different clinical features and prognosis. We can improve the personalized treatment program to this disease through the classification and grading treatment.

Construction and identification of pIRES2-NGF-VEGF165 bicistronic eukaryotic expression vector.

We used a simple and efficient method to construct the bicistronic eukaryotic expression vector pIRES2-NGF-VEGF165. The nerve growth factor (NGF) gene was obtained from the genomic DNA of human peripheral blood mononuclear cells by polymerase chain reaction. The NGF cDNA fragment was inserted into the multiple cloning sites of the pIRES2-EGFP vector to generate the bicistronic eukaryotic expression plasmid pIRES2-NGF-EGFP. The vascular endothelial growth factor 165 (VEGF165) gene was obtained from the pIRES2-VEGF165-EGFP plasmid by polymerase chain reaction. Next, the VEGF165 cDNA fragment was cloned into pIRES2-NGF-EGFP in place of enhanced green fluorescent protein creating the plasmid pIRES2-NGF-VEGF165. pIRES2-NGF-VEGF165 was transfected into HEK293 cells and reverse transcription-polymerase chain reaction and Western blot analysis were used to test the co-expression of double genes. The NGF and VEGF165 genes were cloned and the DNA was sequenced, which revealed that NGF and VEGF165 were consistent with the sequence recorded in GenBank. Restriction analysis showed that the NGF and VEGF165 genes were inserted into the expression vector pIRES2-EGFP. Transfection of pIRES2-NGF-VEGF165 into HEK293 cells resulted in expression of the double gene at the mRNA and protein levels. The NGF and VEGF165 coexpression plasmid provides a novel expression system, enabling further study of the functions of the NGF and VEGF165 genes.

Construction and identification of pIRES2-LIF-NT-3 bicistronic eukaryotic expression vector.

We used a simple and efficient method to construct a bicistronic eukaryotic expression vector pIRES2-LIF-NT-3. The leukemia inhibitory factor (LIF) and neurotrophin-3 (NT-3) genes were obtained from the genomic DNA of human peripheral blood mononuclear cells by polymerase chain reaction. The LIF cDNA fragment was inserted into the multiple cloning sites of a vector containing internal ribosome entry site and enhanced green fluorescent protein (EGFP) (pIRES2-EGFP) to generate the bicistronic eukaryotic expression plasmid pIRES2-LIF-EGFP. Next, the NT-3 cDNA fragment was cloned into pIRES2-LIF-EGFP in place of EGFP to create the plasmid pIRES2-LIF-NT-3. pIRES2-LIF-NT-3 was transfected into HEK293 cells and reverse transcription-polymerase chain reaction and Western blotting were used to test the co-expression of double genes. LIF and NT-3 genes were cloned and the DNA was sequenced. Sequencing analysis revealed that LIF and NT-3 were consistent with the sequence recorded in GenBank. Restriction analysis indicated that the LIF and NT-3 genes were inserted correctly into the expression vector pIRES2-EGFP. Following transfection of pIRES2-LIF-NT-3 into HEK293 cells, the double gene was expressed at the mRNA and protein levels. The LIF and NT-3 coexpression plasmid is a novel expression system that will enable further study of the functions of the LIF and NT-3 genes.

Construction and identification of pIRES2-VEGF165-NT-3 bicistronic eukaryotic expression vector.

We used a simple and efficient method to construct the bicistronic eukaryotic expression vector pIRES2-VEGF165-NT-3. The neurotrophin-3 (NT-3) gene was obtained from the genomic DNA of human peripheral blood mononuclear cells by polymerase chain reaction. The NT-3 cDNA fragment was cloned into the pIRES2-VEGF165-EGFP vector in place of enhanced green fluorescent protein (EGFP) to create the plasmid pIRES2-VEGF165-NT-3. Next, pIRES2-VEGF165-NT-3 was transfected into HEK293 cells, and reverse transcription-polymerase chain reaction and Western blotting were used to test co-expression of the double genes. The vascular endothelial growth factor 165 (VEGF165) and NT-3 genes were cloned; DNA sequencing analysis demonstrated that the VEGF165 and NT-3 sequences were the same as those recorded in GenBank. Restriction analysis indicated that the VEGF165 and NT-3 genes were correctly inserted into the expression vector pIRES2-EGFP. The double gene was expressed at both the mRNA and protein levels. The VEGF165 and NT-3 co-expression plasmid was successfully constructed, providing a novel expression system for further study of the functions of the VEGF165 and NT-3 genes.

[Comparison of four techniques in the treatment of little's area epistaxis].

OBJECTIVE: To probe the most effective technique in the treatment of little's area epistaxis. METHOD: 851 patients were separately treated with four techniques. The effects of sclerosant mucosa injection, cryotherapy, CO2 laser and chemical cautery in the treatment of epistaxis were compared. RESULT: The effective rate of sclerosant mucosa injection is 92.4%, CO2 laser 75.8%, Cryotherapy 76.4%, Chemical cautery 73.8%. No side effect was found. CONCLUSION: Sclerosant mucosa injection is superior to the others.

[Microwave treatment of ethmoidal nerve under nasal endoscopy in the patients with allergic rhinitis].

OBJECTIVE: To study the effect of microwave treatment of ethmoidal nerve on allergic rhinitis. METHOD: 106 cases of allergic rhinitis patients were treated with ethmoidal nerve microwave under nasal endoscope. RESULT: It showed marked effect in 89 cases(84.0%), immprovement in 12 cases(11.3%) and failed in 5 cases (4.7%) in one year follow-up. The overall effective rate was 95.3%. CONCLUSION: This result indicated that the microwave tissue coagulation in treating allergic rhinitis unde nasal endoscope is a good method for clinical treatment.

[Morphofunctional characteristics of the regulatory systems of the large intestine in salmonellosis]. / Morfofunktsional'nye osobennosti reguliatornykh sistem tolstoi kishki pri sal'monelleze.

Morphofunctional alterations occurring in the colon wall indicate complex interactions of the morphological structures participating in the regulation of the intestinal function in salmonellosis. In the early period (24 hours) of maximum decrease in the mediator activity in the nerve structures the number of enterochromaffin cells and the granulation index increased, while in the period of maximum tension of nerve elements (7 days) a decrease in the enterochromaffin cells and granulation index was noted. At later periods (21 days) a relative morphofunctional stabilization of the mucous components and the intramural ganglia has been revealed.