Stethoscope-guided Supervised Contrastive Learning for Cross-domain Adaptation on Respiratory Sound Classification

Despite the remarkable advances in deep learning technology, achieving satisfactory performance in lung sound classification remains a challenge due to the scarcity of available data. Moreover, the respiratory sound samples are collected from a variety of electronic stethoscopes, which could potentially introduce biases into the trained models. When a significant distribution shift occurs within the test dataset or in a practical scenario, it can substantially decrease the performance. To tackle this issue, we introduce cross-domain adaptation techniques, which transfer the knowledge from a source domain to a distinct target domain. In particular, by considering different stethoscope types as individual domains, we propose a novel stethoscope-guided supervised contrastive learning approach. This method can mitigate any domain-related disparities and thus enables the model to distinguish respiratory sounds of the recording variation of the stethoscope. The experimental results on the ICBHI dataset demonstrate that the proposed methods are effective in reducing the domain dependency and achieving the ICBHI Score of 61.71%, which is a significant improvement of 2.16% over the baseline.Comment: accepted to ICASSP 202

Early Dural Sac Termination with Lumbar Disc Herniation: A Mimic of Nerve Root Anomalies

The precise location of the dural sac (DS) end is necessary for preventing neural injury during spinal surgery or procedures. There has been no report on problems with spine surgery in patients with early DS termination. A 28-year-old woman presented with low back and leg pain involving the left S1 nerve root. Magnetic resonance imaging (MRI) revealed early DS termination at the lower one-third of the L5 vertebra and lumbar disc herniation at the L5/S1. Microscopic discectomy was performed instead of endoscopic discectomy to avoid unpredictable risks. Due to early DS termination, multiple nerve roots were identified, which look like nerve root congenital anomalies (Neidre and Macnab type II anomalies), and multiple separated nerve roots appeared to exit through a single foramen. After wide exposure by hemilaminectomy, which facilitated adequate visualization and mobilization of the involved nerve roots, the ruptured disc was identified and removed with gentle retraction, avoiding risk of excessive nerve root traction. Unlike other nerve root anomalies, early DS termination could be detected easily with preoperative MRI. Although this condition appears similar to other nerve root anomalies in the surgical field, it is possible to avoid inadvertent neural injury by closely investigating preoperative MRI. If early DS termination is suspected, it is necessary to consider a safer surgical approach

Impact of the Metabolic Syndrome on the Clinical Outcome of Patients with Acute ST-Elevation Myocardial Infarction

We sought to determine the prevalence of metabolic syndrome (MS) in patients with acute myocardial infarction and its effect on clinical outcomes. Employing data from the Korea Acute Myocardial Infarction Registry, a total of 1,990 patients suffered from acute ST-elevation myocardial infarction (STEMI) between November 2005 and December 2006 were categorized according to the National Cholesterol Education Program-Adult Treatment Panel III criteria of MS. Primary study outcomes included major adverse cardiac events (MACE) during one-year follow-up. Patients were grouped based on existence of MS: group I: MS (n=1,182, 777 men, 62.8±12.3 yr); group II: Non-MS (n=808, 675 men, 64.2±13.1 yr). Group I showed lower left ventricular ejection fraction (LVEF) (P=0.005). There were no differences between two groups in the coronary angiographic findings except for multivessel involvement (P=0.01). The incidence of in-hospital death was higher in group I than in group II (P=0.047), but the rates of composite MACE during one-year clinical follow-up showed no significant differences. Multivariate analysis showed that low LVEF, old age, MS, low high density lipoprotein cholesterol and multivessel involvement were associated with high in-hospital death rate. In conclusion, MS is an important predictor for in-hospital death in patients with STEMI

A Functional Polymorphism on Chromosome 15q25 Associated with Survival of Early Stage Non–Small-Cell Lung Cancer

Introduction:The 15q25 region has been associated with lung-cancer risk and might also be associated with the prognosis of lung cancer. This study was conducted to determine the impact of a functional polymorphism in the CHRNA3 gene on chromosome 15q25 in the survival of patients with early-stage non–small-cell lung cancer (NSCLC).Methods:Five hundred and eighty-three consecutive patients with surgically resected NSCLC were enrolled. The rs6495309C > T polymorphism in the promoter of the CHRNA3 gene was investigated. The association between genotype and overall survival (OS) and disease-free survival (DFS) was analyzed.Results:Patients with the rs6495309 CT or TT genotype had a significantly better OS and DFS than the rs6495309 CC genotype (adjusted hazard ratio for OS = 0.56, 95% confidence interval = 0.41–0.75, p = 0.0001; and adjusted hazard ratio for DFS = 0.61, 95% confidence interval = 0.48–0.79, p = 0.0001). An association between the rs6495309C > T polymorphism and survival outcome was demonstrated in smokers and never-smokers, and in squamous-cell carcinomas and adenocarcinomas.Conclusion:The CHRNA3 rs6495309C > T polymorphism may affect survival in patients with early-stage NSCLC. Analysis of the rs6495309C > T polymorphism can help identify patients at high risk of a poor disease outcome