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1.
To screen and evaluate protein biomarkers for the detection of gliomas (Astrocytoma grade Ⅰ-Ⅳ) from healthy individuals and gliomas from brain benign tumors by using surface enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS) coupled with an artificial neural network (ANN) algorithm. SELDI-TOF-MS protein fingerprinting of serum from 105 brain tumor patients and healthy individuals, included 28 patients with glioma (Astrocytoma Ⅰ-Ⅳ), 37 patients with brain benign tumor, and 40 age-matched healthy individuals. Two thirds of the total samples of every compared pair as training set were used to set up discriminating patterns, and one third of total samples of every compared pair as test set were used to cross-validate; simultaneously, discriminate-cluster analysis derived SPSS 10.0 software was used to compare Astrocytoma grade Ⅰ-Ⅱ with grade Ⅲ-Ⅳ ones. An accuracy of 95.7%, sensitivity of 88.9%, specificity of 100%, positive predictive value of 90% and negative predictive value of 100% were obtained in a blinded test set comparing gliomas patients with healthy individuals; an accuracy of 86.4%, sensitivity of 88.9%, specificity of 84.6%, positive predictive value of 90% and negative predictive value of 85.7% were obtained when patient's gliomas was compared with benign brain tumor. Total accuracy of 85.7%, accuracy of grade Ⅰ-Ⅱ Astrocytoma was 86.7%, accuracy ofⅢ-Ⅳ Astrocytoma was 84.6% were obtained when grade Ⅰ-Ⅱ Astrocytoma was compared with grade Ⅲ-Ⅳ ones (discriminant analysis). SELDI-TOF-MS combined with bioinformatics tools, could greatly facilitate the discovery of better biomarkers. The high sensitivity and specificity achieved by the use of selected biomarkers showed great potential application for the discrimination of gliomas patients from healthy individuals and glioma from brain benign tumors.  相似文献   

2.
Objective: To develop a new bioinformatic tool based on a data-mining approach for extraction of the most infor-mative proteins that could be used to fred the potential biomarkers for the detection of cancer. Methods: Two independent datasets from serum samples of 253 ovarian cancer and 167 breast cancer patients were used. The samples were examined by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). The datasets were used to extract the informative proteins using a data-mining method in the discrete stationary wavelet transform domain. As a dimensionality re-duction procedure, the hard threshoiding method was applied to reduce the number of wavelet coefficients. Also, a distance measure was used to select the most discriminative coefficients. To find the potential biomarkers using the selected wavelet coefficients, we applied the inverse discrete stationary wavelet transform combined with a two-sided t-test. Results: From the ovarian cancer dataset, a set of five proteins were detected as potential biomarkers that could be used to identify the cancer patients from the healthy cases with accuracy, sensitivity, and specificity of 100%. Also, from the breast cancer dataset, a set of eight proteins were found as the potential biomarkers that could separate the healthy cases from the cancer patients with accuracy of 98.26%, sensitivity of 100%, and specificity of 95.6%. Conclusion: The results have shown that the new bioinformatic tool can be used in combination with the high-throughput proteomic data such as SELDI-TOF MS to find the potential biomarkers with high discriminative power.  相似文献   

3.
INTRODUCTION Ovarian cancer is the most lethal gynecologicmalignancy. Poor survival rates are mainly attribut-able to late diagnosis. Most patients at diagnosis haveadvanced stage disease. The 5-year survival rate forlate clinical stage ovarian cancer is only 25%, but forearly stage disease, the survival rate can be as high as90%. CA125, the most widely used biomarker forovarian cancer, does not have a satisfying positivepredictive value. In early stage ovarian cancer,40%–50% pati…  相似文献   

4.

Objective

Biomarker assay is a noninvasive method for the early detection of esophageal squamous cell carcinoma (ESCC). Searching for new biomarkers with high specificity and sensitivity is very important for the early detection of ESCC. Serum surface-enhanced laser desorption/ionization-time of flight mass spectrometry (SELDI-TOF-MS) is a high throughput technology for identifying cancer biomarkers using drops of sera.

Methods

In this study, 185 serum samples were taken from ESCC patients in a high incidence area and screened by SELDI. A support vector machine (SVM) algorithm was adopted to analyze the samples.

Results

The SVM patterns successfully distinguished ESCC from pre-cancerous lesions (PCLs). Also, types of PCL, including dysplasia (DYS) and basal cell hyperplasia (BCH), and healthy controls (HC) were distinguished with an accuracy of 95.2% (DYS), 96.6% (BCH), and 93.8% (HC), respectively. A marker of 25.1 kDa was identified in the ESCC patterns whose peak intensity was observed to increase significantly during the development of esophageal carcinogenesis, and to decrease obviously after surgery.

Conclusions

We selected five ESCC biomarkers to form a diagnostic pattern which can discriminate among the different stages of esophageal carcinogenesis. This pattern can significantly improve the detection of ESCC.  相似文献   

5.
Contract cheating occurs when students outsource assessed work. In this study, we asked experienced markers from four disciplines to detect contract cheating in a set of 20 discipline-specific assignments. We then conducted a training workshop to improve their detection accuracy, and afterwards asked them to detect contract cheating in 20 new assignments. We analysed the data in terms of sensitivity (the rate at which markers spotted contract cheating) and specificity (the rate at which markers spotted real student work). Pre-workshop marker sensitivity was 58% and specificity was 83%. Post-workshop marker sensitivity was 82% and specificity was 87%. The increase in sensitivity was statistically significant, but the increase in specificity was not. These results indicate that markers can often detect contract cheating when asked to do so, and that training may be helpful in improving their accuracy. We suggest that markers’ suspicions may be crucial in addressing contract cheating.  相似文献   

6.
Objectives： To detect the serum proteomic patterns by using SELDI-TOF-MS （surface enhanced laser desorption/ ionization-time of flight-mass spectrometry） technology and CM10 ProteinChip in colorectal cancer （CRC） patients, and to evaluate the significance of the proteomic patterns in the tumour staging of colorectal cancer. Methods： SELDI-TOF-MS and CM10 ProteinChip were used to detect the serum proteomic patterns of 76 patients with colorectal cancer, among them, 10 Stage Ⅰ, 19 Stage Ⅱ, 16 Stage Ⅲ and 31 Stage Ⅳ samples. Different stage models were developed and validated by support vector machines, disctiminant analysis and time-sequence analysis. Results： The Model Ⅰ formed by 6 protein peaks （m/z： 2759.58, 2964.66, 2048.01, 4795.90, 4139.77 and 37761.60） could be used to distinguish local CRC patients （Stage Ⅰ and Stage Ⅱ） from regional CRC patients （Stage Ⅲ） with an accuracy of 86.67% （39/45）. The Model Ⅱ formed by 3 protein peaks （m/z： 6885.30, 2058.32 and 8567,75） could be used to distinguish locoregional CRC patients （Stage Ⅰ, Stage Ⅱ and Stage Ⅲ） from systematic CRC patients （Stage IV） With an accuracy of 75.00% （57/76）. The Model Ⅲ could distinguish Stage Ⅰ from Stage Ⅱ with an accuracy of 86.21% （25/29）. The Model Ⅳ could distinguish Stage Ⅰ from Stage Ⅲ with accuracy of 84.62% （22/26）. The Model Ⅴ could distinguish Stage Ⅱ from Stage Ⅲ with accuracy of 85.71% （30/35）. The Model Ⅵ could distinguish Stage Ⅱ from Stage Ⅳ with accuracy of 80.00% （40/50）. The Model Ⅶ could distinguish Stage Ⅲ from Stage Ⅳ with accuracy of 78.72% （37/47）. Different stage groups could be distinguished by the two-dimensional scattered spots figure obviously. Conclusion： This method showed great success in preoperatively determining the colorectal cancer stage of patients.  相似文献   

7.
Feng  Lei  Zhou  Daizhan  Luo  Chenqi  Shen  Junhui  Wang  Wenzhe  Lu  Yifei  Wu  Jian  Yao  Ke 《Journal of Zhejiang University. Science. B》2021,22(6):504-511
The prompt detection and proper evaluation of necrotic retinal region are especially important for the diagnosis and treatment of acute retinal necrosis(ARN). The potential application of artificial intelligence(AI) algorithms in these areas of clinical research has not been reported previously. The present study aims to create a computational algorithm for the automated detection and evaluation of retinal necrosis from retinal fundus photographs. A total of 149 wide-angle fundus photographs from40 eyes of 32 ARN patients were collected, and the U-Net method was used to construct the AI algorithm. Thereby, a novel algorithm based on deep machine learning in detection and evaluation of retinal necrosis was constructed for the first time. This algorithm had an area under the receiver operating curve of 0.92, with 86% sensitivity and 88% specificity in the detection of retinal necrosis. For the purpose of retinal necrosis evaluation, necrotic areas calculated by the AI algorithm were significantly positively correlated with viral load in aqueous humor samples(R2=0.7444, P0.0001) and therapeutic response of ARN(R2=0.999, P0.0001). Therefore, our AI algorithm has a potential application in the clinical aided diagnosis of ARN, evaluation of ARN severity, and treatment response monitoring.  相似文献   

8.
目的：探讨应用BP神经网络技术建立诊断模型来判断膀胱癌的可行性。方法：153例患者分为训练集和测试集,应用BP神经网络模型,建立人工神经网络诊断模型,然后随机抽样测试样本输入模型进行预测。结果：人工神经网络预测膀胱癌的灵敏度为100％,特异度为92．3％。结论：人工神经网络诊断模型对膀胱癌的判断有良好的诊断性能。  相似文献   

9.
Diagnosis and treatment of breast cancer have been improved during the last decade; however, breast cancer is still a leading cause of death among women in the whole world. Early detection and accurate diagnosis of this disease has been demonstrated an approach to long survival of the patients. As an attempt to develop a reliable diagnosing method for breast cancer, we integrated support vector machine (SVM), k-nearest neighbor and probabilistic neural network into a complex machine learning approach to detect malignant breast tumour through a set of indicators consisting of age and ten cellular features of fine-needle aspiration of breast which were ranked according to signal-to-noise ratio to identify determinants distinguishing benign breast tumours from malignant ones. The method turned out to significantly improve the diagnosis, with a sensitivity of 94.04%, a specificity of 97.37%, and an overall accuracy up to 96.24% when SVM was adopted with the sigmoid kernel function under 5-fold cross validation. The results suggest that SVM is a promising methodology to be further developed into a practical adjunct implement to help discerning benign and malignant breast tumours and thus reduce the incidence of misdiagnosis.  相似文献   

10.
Prostate cancer (PCa) is the second most common male cancer worldwide and the fifth leading cause of death from cancer in men. Early detection and risk stratification is the most effective way to improve the survival of PCa patients. Current PCa biomarkers lack sufficient sensitivity and specificity to cancer. Metabolite biomarkers are evolving as a new diagnostic tool. This review is aimed to evaluate the potential of metabolite biomarkers for early detection, risk assessment, and monitoring of PCa. Of the 154 identified publications, 27 and 38 were original papers on urine and serum metabolomics, respectively. Nuclear magnetic resonance (NMR) is a promising method for measuring concentrations of metabolites in complex samples with good reproducibility, high sensitivity, and simple sample processing. Especially urine-based NMR metabolomics has the potential to be a cost-efficient method for the early detection of PCa, risk stratification, and monitoring treatment efficacy.  相似文献   

11.
Detection of PCV2 DNA by SYBR Green I-based quantitative PCR   总被引：5，自引：0，他引：5  
We developed an assay for the detection and quantitation of porcine circovirus type 2 (PCV2) with the SYBR Green I-based real-time PCR. The real-time PCR provides a broad dynamic range, detecting from 103 to 1011 copies of DNA per reaction. No cross-reactions were found in specimens containing PCV1. Because of the high sensitivity and specificity of the assay with a relatively rapid and simple procedure, real-time PCR can be used as a routine assay for the clinical diagnosis of PCV2 infection. In this study we applied real-time PCR assay to 80 clinical samples, collected from 40 pigs with postweaning multisystemic wasting syndrome (PMWS) and 40 healthy pigs in comparison with conventional PCR assay. In 56 of 80 samples, PCV2 DNA was de-tected by conventional PCR assay. All samples positive for PCV2 DNA in conventional PCR assay were also positive in real-time assay, and 12 of 24 samples that tested negative for PCV2 DNA in the conventional assay were tested positive in real-time PCR assay. Real-time PCR assay increased the number of samples in which PCV2 was detected by 15%. It is, therefore, considered to be a useful tool for the detection of PCV2.  相似文献   

12.
The use of visible-near infrared (NIR) spectroscopy was explored as a tool to discriminate two new tomato plant varieties in China (Zheza205 and Zheza207).In this study,82 top-canopy leaves of Zheza205 and 86 top-canopy leaves of Zheza207 were measured in visible-NIR reflectance mode.Discriminant models were developed using principal component analysis (PCA),discriminant analysis (DA),and discriminant partial least squares (DPLS) regression methods.After outliers detection,the samples were randomly split into two sets,one used as a calibration set (n=82) and the remaining samples as a validation set (n=82).When predicting the variety of the samples in validation set,the classification correctness of the DPLS model after optimizing spectral pretreatment was up to 93%.The DPLS model with raw spectra after multiplicative scatter correction and Savitzky-Golay filter smoothing pretreatments had the best satisfactory calibration and prediction abilities (correlation coefficient of calibration (Rc)=0.920,root mean square errors of calibration=0.196,and root mean square errors of prediction=0.216).The results show that visible-NIR spectroscopy might be a suitable alternative tool to discriminate tomato plant varieties on-site.  相似文献   

13.
Objective: to explore a new serological method for detecting Helicobac ter pylori ( H. pylori ) infection. Methods: Serum soluble antigen of H. p ylor i was detected by using avidin-biotin ELISA technique to evaluate the status of H. pylori infection and for comparison with rapid urease test ( RUT ), histo logi c examination and serology. Results: The sensitivity, specificity, positive pred ictive value and negative predictive value were 77.46%, 91.07%, 91.67% a nd 76.12 %, respectively. The prevalence rate of serum H. pylori soluble antigen in 138 patients undergoing endoscopy was similar to the rate obtained by 14 C-UBT met hods ( P>0.05 ). Conclusions: The detection of serum H. pylori solub le antigen( HpSAg) could be used as a new serological method which is accurate, and convenie nt, not affected by the memorizing reaction of serum antibody; is more sensitive , m ore specific and suitable for clinical diagnosis, and evaluation of eradication and for follow-up of H. pylori as well as for detection in children and pre gnant women.  相似文献   

14.
目的：研究人体片形吸虫病ELISA检测试剂盒的检测效果。方法：采用云南大理本地采集的牛体片形吸虫成虫制备可溶性粗抗原,包被反应板,采用人体片形吸虫病ELISA法（FAWA-ELISA）进行研究,分别检测26份片形吸虫患者血清、102份其他寄生虫病患者血清和25份健康人血清,评价检测试剂盒的检测效果。结果：检测试剂盒的敏感性为100.0%、特异性分别为95.28%（95%CI：98.9%～91.2%）,约登指数分别为0.95。结论：FAWA-ELISA试剂盒检测效果较好,且成本相对较低,可适宜用于云南片形吸虫病流行区流行病学筛查,减轻病原学检测的工作量。  相似文献   

15.
A method of medical image segmentation based on support vector machine （SVM） for density estimation is presented. We used this estimator to construct a prior model of the image intensity and curvature profile of the structure from training images. When segmenting a novel image similar to the training images, the technique of narrow level set method is used. The higher dimensional surface evolution metric is defined by the prior model instead of by energy minimization function. This method offers several advantages. First, SVM for density estimation is consistent and its solution is sparse. Second, compared to the traditional level set methods, this method incorporates shape information on the object to be segmented into the segmentation process. Segmentation results are demonstrated on synthetic images, MR images and ultrasonic images.  相似文献   

16.
Objective: to explore a new serological method for detectingHelicobacter pylori (H. pylori) infection. Methods: Serum soluble antigen ofH. pylori was detected by using avidin-biotin ELISA technique to evaluate the status ofH. pylori infection and for comparison with rapid urease test (RUT), histologic examination and serology. Results: The sensitivity, specificity, positive predictive value and negative predictive value were 77.46%, 91.07%, 91.67% and 76.12%, respectively. The prevalence rate of serumH. pylori soluble antigen in 138 patients undergoing endoscopy was similar to the rate obtained by14C-UBT methods (P>0.05). Conclusions: The detection of serumH. pylori soluble antigen(HpSAg) could be used as a new serological method which is accurate, and convenient, not affected by the memorizing reaction of serum antibody; is more sensitive, more specific and suitable for clinical diagnosis, and evaluation of eradication and for follow-up ofH. pylori as well as for detection in children and pregnant women. Project supported by Zhejiang Provincial Health Bureau (No. 2000A118), China  相似文献   

17.
目的：观察补充胆红素对不同负荷运动造成的肝细胞凋亡的影响,为运动营养补剂的研发,减少运动性损伤提供一定的实验依据.方法：以53只健康雄性SD大鼠为研究对象,随机分成7个组,即安静对照组、中等负荷运动组、中等负荷运动＋胆红素组、大负荷运动组、大负荷运动＋胆红素组,力竭运动组、力竭运动＋胆红素组,通过实验检测肝细胞凋亡情况,测量肝组织SOD的活性和MDA含量.结果表明：力竭运动和大负荷运动能诱导大鼠肝细胞凋亡增加;补充胆红素使其肝细胞凋亡率降低,说明胆红素能提高机体抗氧化能力.  相似文献   

18.
Worldwide there has been a significant increase in the incidence of oropharyngeal squamous cell carcinoma (OPSCC) etiologically attributed to oncogenic human papillomavirus (HPV). Reliable and accurate identification and detection tools are important as the incidence of HPV-related cancer is on the rise. Several HPV detection methods for OPSCC have been developed and each has its own advantages and disadvantages in regard to sensitivity, specificity, and technical difficulty. This review summarizes our current knowledge of molecular methods for detecting HPV in OPSCC, including HPV DNA/RNA polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), p16 immunohistochemistry (IHC), and DNA/RNA in situ hybridization (ISH) assays. This summary may facilitate the selection of a suitable method for detecting HPV infection, and therefore may help in the early diagnosis of HPV-related carcinoma to reduce its mortality, incidence, and morbidity.  相似文献   

19.
Automatic segmentation of bladder in CT images   总被引：1，自引：0，他引：1  
Segmentation of the bladder in computerized tomography （CT） images is an important step in radiation therapy planning of prostate cancer. We present a new segmentation scheme to automatically delineate the bladder contour in CT images with three major steps. First, we use the mean shift algorithm to obtain a clustered image containing the rough contour of the bladder, which is then extracted in the second step by applying a region-growing algorithm with the initial seed point selected from a line-by-line scanning process. The third step is to refine the bladder contour more accurately using the rolling-ball algorithm. These steps are then extended to segment the bladder volume in a slice-by-slice manner. The obtained results were compared to manual segmentation by radiation oncologists. The average values of sensitivity, specificity, positive predictive value, negative predictive value, and Hausdorffdistance are 86.5%, 96.3%, 90.5%, 96.5%, and 2.8 pixels, respectively. The results show that the bladder can be accurately segmented.  相似文献   

20.
在对3维模型2维投影图利用区域的Fourier变换提取其形状特征的基础上,提出了一种新的基于特征序列为训练模型的异常检测算法。首先对高维特征序列进行约减至低维序列;其次,引入序列局部模式的相似度和异常值的定义对任意的测试集区分异常。通过PSB数据集实验证明了该方法的有效性和合理性。  相似文献   

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