Trace Elements Of Chemical Pattern Recognition Early Diagnosis Of Lung Cancer And Cardiovascular Diseases Methodology

In this study, 465 batches of bio-samples were collected in total, including 100 batches of hair, 173 batches of whole blood, 95 batches of urine from healthy people; 27 batches of urine from lung cancer patients; 24 batches of hair, 24 batches of whole blood, and 22 batches of urine from cardiovascular diseases patients in the city of Shenyang. 9 kinds of trace elements in these bio-samples were determined. The influence of age on the concentrations of trace elements was studied. A data matrix of concentrations of elements existed in the bio-samples from healthy people, lung cancer patients, and cardiovascular diseases patients were established and then the results were classified by using discriminant analysis, to attain the aim of early prediction about lung cancer and cardiovascular diseases.The contents of elements in nitric acid from different factories, the digestion systems, and the instrument parameters of inductively coupled plasma atomic emission spectrometry were studied. The digestion system for the hair and the whole blood was HNO₃-HClO₄ (4: 1, V/V), the digestion system for the urine was HNO₃-HClO₄-H₂O₂ (10:6:1, V/V). High frequency power was 1.2 kw, cooling gas velocity was 18 L·min^-1, and atomizer chamber gas pressure was 45 psi.After digested, the concentrations of Cr, Fe, Mn, A1, Cd, Cu, Zn, Ni in the bio-samples were determined by inductively coupled plasma atomic emission spectrometry, and Se was determined by atomic fluorescence spectrometry. The working ranges were: Cr 0.001～0.5μg·mL^-1, Fe 0.05～100.0μg·mL^-1, Mn 0.001～0.5μg·mL^-1, Al0.01～5.0μg.mL^-1, Cd 0.0005～0.05μg-mL^-1, Cu 0.01～2.5μg·mL^-1, Zn 0.1～20.0μg·mL^-1, Ni 0.005～0.5μg·mL^-1, Se 0.001～0.05μg·mL^-1. The correlation coefficients were between 0.9990 0.9998. The limits of determination were 0.0004～0.03μg-mL^-1. The precisions of instrument were 0.19 %～4.1%. The precisions of methods were between 0.84 %～9.0 %. The recoveries were between 80.0 %～120.0 %. Fisher's linear discriminant functions for the concentrations of elements in the urine from healthy people and lung cancer patients: healthy Y₁=-5.055+48.829 C_cr-5.988 C_Fe+256.662 C_Mn+14.844 C_Al+189.535 C_Cd+9.427 C_Cu-1.968 C_Zn+104.094 C_Ni+415.428 Cse; lung cancer Y₂=-26.868+8.607 C_Cr-21.003 C_Fe+294.541 C_Mn+26.018 C_Al-713.136 C_cd+33.973 C_Cu+0.039 C_Zn+612.649 C_Ni+1119.425 C_se. The classification accuracy was 98.3 %. Fisher's linear discriminant functions for the concentrations of elements in the hair from healthy people and cardiovascular diseases patients: healthy Y₁=-32.233+3.306 C_Cr-0.055 C_Fe+0.153 C_Mn+0.672 C_Al+17.007 C_Cd+0.497 C_Cu+0.024 C_Zn+4.260 C_Ni+118.314 C_se, cardiovascular diseases Y₂=-22.420+2.098 C_Cr-0.080 C_Fe+0.331 C_Mn+0.709 C_Al+16.613 C_Cd+0.587 C_Cu+0.027 C_Zn+3.572 C_Ni+76.122 C_Se. The classification accuracy was 93.4 %. Fisher's linear discriminant functions for the concentrations of elements in the whole blood from healthy people and cardiovascular diseases patients: healthy Y₁=-26.957-4.874 C_Cr+0.049 C_Fe-0.784 C_Mn+5.389 C_Al-70.799 C_Cd+9.078 C_Cu-0.929 C_Zn+1.046 C_Ni+300.101 C_Se; cardiovascular diseases Y₂=-22.126-6.245 C_Cr+0.051 C_Fe-4.841 C_Mn+ 5.297 C_Al-82.401 C_Cd+9.183 C_cu-0.971 C_Zn+0.245 C_Ni+228.084 C_Se. The classification accuracy was 89.7 %. Fisher's linear discriminant functions for the concentrations of elements in the urine from healthy people and cardiovascular diseases patients: healthy Y₁=-7.533+32.516 C_Cr-4.387 C_Fe+233.627 C_Mn+15.600 C_Al+ 308.008 C_Cd+15.666 C_Cu-- 6.042 C_Zn+183.050 C_Ni+1205.464 Cse; cardiovascular diseases Y₂=-4.949+39.471 C_Cr-2.418 C_Fe+91.174 C_Mn+10.391 C_Al+ 373.184 C_Cd-1.379 C_Cu-5.322 C_Zn+166.280 C_Ni+399.103 Cse. The classification accuracy was 91.3%. The results showed that there existed notable differences of trace elements' concentrations in the hair, whole blood and urine form healthy people, lung cancer patients, and cardiovascular diseases patients. The trace element chemical pattern recognition established in this study provided a useful method for early diagnosis and prevention, and had clinical meanings.