1.Establishment of the Mathematical Model for PMI Estimation Using FTIR Spec-troscopy and Data Mining Method
Lei WANG ; Xin-Chao QIN ; Han-Cheng LIN ; Kai-Fei DENG ; Yi-Wen LUO ; Qi-Ran SUN ; Qiu-Xiang DU ; Zhen-Yuan WANG ; Ya TUO ; Jun-Hong SUN
Journal of Forensic Medicine 2018;34(1):1-6,12
Objective To analyse the relationship between Fourier transform infrared (FTIR) spectrum ofrat's spleen tissue and postmortem interval (PMI) for PMI estimation using FTIR spectroscopy combinedwith data mining method. Methods Rats were sacrificed by cervical dislocation, and the cadavers were placed at 20 ℃. The FTIR spectrum data of rats' spleen tissues were taken and measured at different time points. After pretreatment, the data was analysed by data mining method. Results The absorption peak intensity of rat's spleen tissue spectrum changed with the PMI, while the absorption peak position was unchanged. The results of principal component analysis (PCA) showed that the cumulative contribution rate of the first three principal components was 96%. There was an obvious clustering tendency for the spectrum sample at each time point. The methods of partial least squares discriminant analysis (PLS- DA) and support vector machine classification (SVMC) effectively divided the spectrum samples with different PMI into four categories (0-24 h, 48-72 h, 96-120 h and 144-168 h). The determination coefficient (R2) of the PMI estimation model established by PLS regression analysis was 0.96, and the root mean square error of calibration (RMSEC) and root mean square error of cross validation (RMSECV) were 9.90 h and 11.39 h respectively. In prediction set, the R2 was 0.97, and the root mean square error of prediction (RMSEP) was 10.49 h. Conclusion The FTIR spectrum of the rat's spleen tissue can be effectively analyzed qualitatively and quantitatively by the combination of FTIR spectroscopy and data mining method, and the classification and PLS regression models can be established for PMI estimation.
2.Infrared Spectral Characteristics of Electrical Injuries on Swine Skin Caused by Different Voltages Based on Machine Learning Algorithms
He-Wen DONG ; Wei LI ; Shi-Ying LI ; Kai-Fei DENG ; Nan CAO ; Yi-Wen LUO ; Qi-Ran SUN ; Han-Cheng LIN ; Jing-Feng HUANG ; Ning-Guo LIU ; Ping HUANG
Journal of Forensic Medicine 2018;34(6):619-624
Objective To explore infrared spectrum characteristics of different voltages induced electrical injuries on swine skin by using Fourier transform infrared-microspectroscopy (FTIR-MSP) combined with machine learning algorithms, thus to provide a reference to the identification of electrical skin injuries caused by different voltages.Methods Electrical skin injury model was established on swines.The skin was exposed to 110 V, 220 V and 380 V electric shock for 30 s and then samples were took, with normal skin tissues around the injuries as the control.Combined with the results of continuous section HE staining, the FTIR-MSP spectral data of the corresponding skin tissues were acquired.With the combination of machine learning algorithms such as principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA), different spectral bands were selected (full band 4 000-1 000 cm-1and sub-bands 4 000-3 600 cm-1, 3 600-2 800 cm-1, 2 800-1 800 cm-1, and 1 800-1 000 cm-1), and various pretreatment methods were used such as orthogonal signal correction (OSC), standard normal variables (SNV), multivariate scatter correction (MSC), normalization, and smoothing.Thus, the model was optimized, and the classification effects were compared.Results Compared with simple spectrum analysis, PCA seemed to be better at distinguishing electrical shock groups from the control, but was not able to distinguish different voltages induced groups.PLS-DA based on the 3 600-2 800 cm-1band was used to identify the different voltages induced skin injuries.The OSC could further optimize the robustness of the 3 600-2 800 cm-1band model.Conclusion It is feasible to identify electrical skin injuries caused by different voltages by using FTIR-MSP technique along with machine learning algorithms.
3.Research Progress of MALDI-TOF-IMS in Biomedicine and Its Application Prospect in Forensic Sciences
heng Guan REN ; hua Rong WENG ; Yan SHI ; Ping HUANG ; dong Zheng LI ; Yu SHAO ; fei Kai DENG ; guo Ning LIU ; jiu Yi CHEN
Journal of Forensic Medicine 2017;33(5):522-525
Matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry (MALDI-TOF-IMS) can analysis unknown compounds in sections and obtain molecule imaging by scanning biological tissue sections,which has become a powerful tool for the research of biomarker,lipid distribution and drug metabolism,etc.This article reviews the application of this technique in protein identification,clinical application,drug discovery,lipid research and brain injury.
4.Clinical significance of CASP8AP2 gene methylation in childhood acute lymphoblastic leukemia.
Fei-Fei LIU ; ; Beijing 100045, CHINA. ; Xiao LIU ; ; Beijing 100045, CHINA. ; Kai-Ling WANG ; ; Beijing 100045, CHINA. ; Wei-Jing LI ; ; Beijing 100045, CHINA. ; Guo-Ren DENG ; Chao GAO ; ; Beijing 100045, CHINA. ; Xiao-Xi ZHAO ; ; Beijing 100045, CHINA. ; Min-Yuan WU ; ; Beijing 100045, CHINA. ; Lei CUI ; ; ; Zhi-Gang LI ; ;
Journal of Experimental Hematology 2015;23(1):6-11
OBJECTIVETo study the methylation level in the promoter of caspase 8 associated protein 2 (CASP8AP2) gene between samples at diagnosis and in complete remission, and to investigate its relationship with clinical features and prognosis in children with acute lymphoblastic leukemia (ALL).
METHODSDiagnostic DNA samples from 109 newly diagnosed children with ALL admitted from August 2007 to March 2010, and 94 ALL children in CR (complete remission) among them were collected. Bisulfite modification and MethyLight method established by our research team were used to determine the methylation level of the two key CpG sites (at -1189 and -1176) of the promoter of CASP8AP2 gene.
RESULTSThe average methylation level of the two CpG sites in newly diagnosted samples was higher than that in CR samples (71.1% ± 1.7% vs 64.2% ± 21.2%) (P = 0.008). Analysis with receiver operating characteristic (ROC) curve showed that the area under curve was 0.687 (P = 0.024), indicating that the methylation level of the two CpG sites was able to predict relapse efficiently to some extent, 76.9% was chosed as a cutoff value to divide the patients into high methylation group (49 patients) and low methylation group (60 patients). The incidence of relapse in high methylation group was higher than that in low methylation group (20.4% vs 6.7%) (P = 0.044), five year relapse free survival in high methylation group was also lower than that in low methylation group (Log rank, P = 0.033). Furthermore, high methylation at new diagnosis were correlated with high level of minimal residual disease (MRD) before consolidation therapy (P = 0.011). In the 34 children with MRD ≥ 10(-4) at the end of induction remission, the relapse rate of high methylation patients was significantly higher than that of low methylation patients (8/16 vs 3/18)(P = 0.038).
CONCLUSIONThe abnormal hypermethylation of the two CpG sites (at -1189 and -1176) of the promoter of the CASP8AP2 gene is possibly associated with leukemogenesis in childhood ALL. The treatment outcome is more poor in patients with hypermethylation than that in patients with low methylation. The combination of the methylation level of the two CpG sites and MRD level at the end induction remission is able to predict relapse more effectively.
Apoptosis Regulatory Proteins ; Calcium-Binding Proteins ; Child ; DNA Methylation ; Humans ; Neoplasm, Residual ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Prognosis ; Promoter Regions, Genetic ; Recurrence ; Remission Induction
5.Changes of AFP and beta-hCG in testicular tumors analyzed by a function method.
Xiao-Feng GUAN ; Yao-Liang DENG ; Qi-Ming LIU ; De-Xiong ZHOU ; Yu-Kai YANG ; Kun LU ; Fei LI
National Journal of Andrology 2013;19(1):59-62
OBJECTIVETo establish a new function method for the analysis of a-fetoprotein (AFP) and beta-hCG in testicular tumors.
METHODSWe reexamined the serum levels of AFP and beta-hCG after radical orchiectomy, and calculated the measured coordinate, with the abscissa representing the number of the half-lives of tumor markers, and the ordinate representing the measured value of tumor markers. Referring to the measured value of tumor markers before surgery as a, the number of half-lives as x, and their theoretical value over a period of x elimination half-lives as y (logarithm to the base 2 of y), we calculated the predicted coordinate according to the formula y = log2(a/2x) ==> x + y = log2a (function 1). Then we assessed tumor residue and metastasis by analyzing the relationship between the measured and predicted coordinates.
RESULTSThe pathological examination of case 1 revealed a germ cell tumor of a mixed histological pattern of syncytiotrophoblast and yolk sac tumor. The measured coordinates of AFP and beta-hCG were (2.22, 6.21) and (10, 8.38), and the predicted coordinates (2.22, 6.34) and (10, 4.41) , indicating the elimination of the yolk sac tumor and metastasis of the syncytiotrophoblast tumor. Case 2 demonstrated the mixed pathological nature of teratocarcinoma and yolk sac tumor. The measured coordinates of AFP and beta-hCG were (2.67, -1.03) and (12, -3.32), and the predicted coordinates (2.67, 1.41) and (12, -5.80). But the review times of AFP and beta-hCG were out of the effective range of half-lives, with the measured values below the normal, which suggested no tumor residue or metastasis. Case 3 was found to be embryonal carcinoma. The measured coordinate of AFP was (0.22, 9.25) , and the predicted coordinate (0.22, 9.55) , indicating the elimination of tumor.
CONCLUSIONThe change of the tumor markers predicted by the function method coincided with the natural course of disease in the three cases. The coincidence of the measured with the predicted coordinate after radical orchiectomy indicates no metastasis, while their disagreement suggests possible residue and metastasis of the tumor.
Adult ; Biomarkers, Tumor ; blood ; Chorionic Gonadotropin, beta Subunit, Human ; blood ; Humans ; Male ; Models, Statistical ; Orchiectomy ; Testicular Neoplasms ; metabolism ; pathology ; alpha-Fetoproteins ; analysis
6.A study on the individual adaptability of electronic sphygmomanometer.
Xue-ji FENG ; Qin-kai DENG ; Fei-xue LIANG ; Jian-bo WANG
Chinese Journal of Medical Instrumentation 2009;33(2):95-98
This paper analyzed the limitation of electronic sphygmomanometer based on oscillometry, and according to the characteristics of pulse signal, the author proposed a new method of the characteristic parameter detection based on wavelet transform, and improved its recognition ability on fixed-scale, via resampling rate according to the heartbeat. And the prototype test has been proved that this method is more adaptability for individuals and stability for operation.
Blood Pressure Monitoring, Ambulatory
;
instrumentation
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Individuality
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Signal Processing, Computer-Assisted
;
instrumentation
7.Study on the natural foci of Marmota himalayana plague in Sichuan province
Li-Mao WANG ; Zhi-Danba LUO ; Qi YUE ; Yong-Jun DUAN ; Xiao-Ping ZHU ; Su-Ling MAO ; Lun-Guang LIU ; Hong WANG ; Yi LIU ; Fei XIE ; De-Gang CHEN ; Kai-Hua CHEN ; Bing DENG ; Jun-Xing KANG
Chinese Journal of Epidemiology 2009;30(6):601-605
Objective To explore the existence of natural loci on Marmota himalayana plague in Sichuan province and to provide basis for prevention and control of the disease. Methods Both epidemiological investigation and laboratory tests were used to provide the host animal and fleas of the vectors with Yersinia pestis carriers. Results 30 species of animals were found to belong to 10 orders. Ochotona curzoniae and M.himalayana were the most common ones while 7 species of the fleas belonged to 7 genera and 3 families. M.himalayana was the main reservoirs while Callopsylla dolabris and Oropsylla silantiewi served as vectors. The 13 Y.pestis were identified from 43 Marmota samples. 8 samples were identified under IHA, with the highest titer of herding-dogs serum as 1 : 10 240. 19 samples were F1 antigen positive using RIHA and the highest titer of M.himalayana serum was 1:409 600. The major foci was 4545 km2, distributed at Dege county in Sichuan province. Conclusion We have confirmed the existence of natural foci on M. Himalayana plague in Sichuan province.
8.Analysis of the main components of coptis-evodia herb couple by HPLC-DAD-MS.
Ya-Ting DENG ; Qiong-Feng LIAO ; Kai-Shun BI ; Mei-Cun YAO ; Xiao-fei JIANG ; Zhi-Yong XIE
Acta Pharmaceutica Sinica 2008;43(3):299-302
A comprehensive HPLC-DAD-MS method was developed to study the chemical components of semi-bionic extract of Coptis-Evodia herb couple. The extract was isolated on a Hypersil BDS C18 column (4.6 mm x 200 mm, 5 microm) using acetonitrile-ammonium formic buffer as mobile phase by gradient elution. Detection was performed on DAD and MS equipped with an electrospray ionization (ESI) source by full scan and product full scan on positive mode. The chromatogram of Coptis-Evodia showed seventeen main peaks, eight of which were from Evodia while the others were from Coptis. By comparison of the retention time, the on-line UV spectra and MS spectra, four peaks were identified as jatrorrhizine, hydroxevodiamine, palmatine and berberine, and three peaks were deduced as epiberberine, columbamine and coptisine. In addition, berberine and palmatine were quantitatively determined. No new component was created in the semi-bionic extract of the herb couple, yet the solubilities of berberine and palmatine decreased.
Berberine
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analogs & derivatives
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chemistry
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isolation & purification
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Berberine Alkaloids
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chemistry
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isolation & purification
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Chromatography, High Pressure Liquid
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methods
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Coptis
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chemistry
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Drugs, Chinese Herbal
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Evodia
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chemistry
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Plant Extracts
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chemistry
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Spectrometry, Mass, Electrospray Ionization
9.CT perfusion study of acute local cerebral infarction in rhesus monkeys.
Zhuo-kai HE ; Yi-kai XU ; Wei-jia QIU ; Yan-xian DENG ; Zhi-peng ZHOU ; Zhi-hong HUANG ; Fei-ling FENG ; Ying WEI ; Rui-jing GAN ; Jun-xiong YU
Journal of Southern Medical University 2007;27(5):720-724
OBJECTIVETo explore the value of CT perfusion in early diagnosis and management of superacute local cerebral infarction in rhesus monkeys.
METHODAcute local cerebral infarction was induced in the rhesus monkeys during digital subtraction angiography (DSA) by introduction of pale thrombus prepared from autologous blood into the M1 branch of the middle cerebral artery (MCA). Plain CT scan and CT perfusion scanning were performed at different time points before and after DSA operation, and the results were analyzed in conjunction with the pathologic changes.
RESULTSIschemic lesions were displayed on CT perfusion images, which showed local hypoperfusion, reduced cerebral blood flow and volume, and mean transit time delay in the compromised area. Local hypointense infarct area was identified in plain CT scan 24 h after the DSA operation, and the results were in good agreement with pathological examination during autopsy.
CONCLUSIONCT perfusion imaging of the brain can accurately capture the cerebral perfusion deficits in acute ischemic stroke before morphologic changes take place, and therefore provides good means for thrombolytic treatment evaluation of stroke.
Acute Disease ; Animals ; Brain ; diagnostic imaging ; Brain Ischemia ; diagnosis ; Cerebral Infarction ; diagnosis ; Contrast Media ; administration & dosage ; Early Diagnosis ; Macaca mulatta ; Perfusion ; Sensitivity and Specificity ; Tomography, X-Ray Computed ; methods

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