The Research On Bio Markers And Its Detection Of Lung Disease In Volatiled Organic Compounds And Exhaled Breath Condesate

Lung cancer and pneumonia are the most threatening lung disease to human health. The key to treat the two diseases is to diagnose lung cancer and define pneumonia bacteria species as early as possible. Breath detection diagnoses diseases through the detection of the change of its organic compounds. This method has become very popular to disease research as it’s non-invasive, convenient and fast.This research focused on EBC(Exhaled Breath Condensate) method to detect CEA(Carcinoma Embryonic Antigen), NSE (Neuron Specific Enolase) and SCC (Squamous Cell Carcinoma antigen). VOCs (Volatile Organic Compounds) detection was used to detect the specified biomarker of Escherichia coli, Staphy lococcus aureus and Pseudomonas aeruginosa in pneumonia.1. There are no criteria of EBC collection equipment and method till now. This research designed an EBC collection equipment to detect large protein—CEA, NSE, and SCC. The best detection time was found to be5minutes and the best collection temperature was found to be-10℃. This research also compared the designed EBC collection equipment and commercial EBC collection equipment—coscreen, finding that the designed equipment could collect more EBC and more concentration of CEA under the same collection time and temperature.2. This research analyzed three cancer biomarkers—CEA, NSE and SCC through the analysis of lung cancer type, stages, finding that the concentrations of the biomarkers in the patients were higher than those in the control. Within different lung cancer types, CEA was the most sensitive in adenocarcinoma, with NSE in small cell carcinoma and SCC in squamous carcinoma. Different stages were also compared, finding the higher the stage, the more the concentrations. The concentrations of the three biomarkers in I stage patients were also higher than those in control, suggesting the biomarkers could help detect early stage lung cancer.3. ROC curve was used to analyze the positive threshold of the three biomarkers, finding the positive threshold of CEA was2.15ng/ml, with that of NSE4.65ng/ml, and that of SCC0.45ng/ml. Then the sensitivity and specificity were calculated:the sensitivity of CEA, NSE and SCC was separately72.4%,49.2%and62.9%and the specificity was separately78.6%,83.9%and62.5%. Through the united detection of the three biomarkers, the sensitivity increased to93.3%while the specificity decreased to53.6%, indicating the united detection could enhance the sensitivity.4. This research also detected bacterial pneumonia and found the best detecting time and the best bacteria concentration. Lung organization was infected by different concentrations of Escherichia coli under different detection time. The best detecting time was found24hours by comparing the results of6,12and24hours. The best bacteria concentration was found108/ml by comparing the concentration of0.108/ml and109/ml.5. The research also founded the model of bacteria infecting lung organization and the model of bacteria infecting animal to find the biomarker of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The biomarker of Escherichia coli was found to be hexadecanol (C16H34O), with that of Staphylococcus aureus that of Pseudomonas aeruginosa C18H30O.