1.A new method of measuring the pulse based on facial video.
Feifan ZHAO ; Luping FANG ; Shixiao CHEN
Journal of Biomedical Engineering 2012;29(5):876-918
This paper proposes a new method of non-contact pulse measurement by analyzing a clip of human facial video. The method is based on photo plethysmography (PPG) and independent component analysis (ICA) model. A clip of color facial video shot under normal lighting condition is firstly discomposed into RGB channel sequences. Secondly, by applying ICA to the 3 channel sequences, 3 new independent signals are obtained, among which one signal is close to human pulse wave. Thus the pulse can be measured. In this paper, the principles of PPG and ICA are briefly described and the measurement framework is proposed. The experimental results showed that this novel approach was reasonable and feasible.
Algorithms
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Analysis of Variance
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Facies
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Humans
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Models, Statistical
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Photoplethysmography
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methods
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Principal Component Analysis
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methods
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Pulse
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Video Recording
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methods
2.Degradation kinetics of larotaxel and identification of its degradation products in alkaline condition
Xiaoming LIANG ; Zhenzhen LIU ; Huiyan SHI ; Yuanyuan ZHANG ; Shixiao WANG ; Kaishun BI ; Xiaohui CHEN
Journal of Pharmaceutical Analysis 2017;7(2):118-122
Larotaxel, a new taxane compound prepared by partial synthesis from 10-deacetyl baccatin Ⅲ, is active against tumors. In this research, a selective LC–MS method was developed and validated for the study of degradation kinetics of larotaxel, which was carried out in aqueous solutions with different pH (1.5, 3.0, 5.0, 6.5, 7.4, 9.0, 10 and 11.0) and temperature (0, 25, 37 and 45 °C). The linear range was 0.5–25μg/mL, the intra-and inter-day precisions were less than 7.0%, and accuracy ranged from 97.4–104.5% for each analyte. The observed rate obtained by measuring the remaining intact larotaxel was shown to follow first-order kinetics. The activation energies for degradation were 126.7 and 87.01 kJ/mol at pH 1.5 and 11, respectively. Although larotaxel was stable in pH 5, 6.5 and 7.4 buffers at 37 °C for 24 h during our study, increasing or decreasing the pH of the solutions would decrease its stabilities. Moreover, three main degradation products in alkaline condition were separated by HPLC and identified by Q–TOF–MS. The three degradation products were confirmed as 10-deacetyl larotaxel, 7, 8-cyclopropyl baccatin Ⅲ and 10-deacetyl-7, 8-cyclopropyl baccatin Ⅲ.
3.A clinical analysis of alcoholic liver cirrhosis in South Sichuan area.
Yan PENG ; Changping LI ; Guo CHEN ; Chuankang TANG ; Shixiao TANG ; Yun LI
Chinese Journal of Hepatology 2002;10(6):408-412
Adult
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Age Factors
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Aged
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Alanine Transaminase
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blood
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Alkaline Phosphatase
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blood
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Aspartate Aminotransferases
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blood
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China
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Female
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Hepatitis B
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complications
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Hepatitis C
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complications
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Hospitalization
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statistics & numerical data
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Humans
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Liver Cirrhosis, Alcoholic
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complications
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mortality
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pathology
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Male
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Middle Aged
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Survival Rate
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gamma-Glutamyltransferase
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blood
4.Development of a UPLC–MS/MS method for determination of pimavanserin tartrate in rat plasma:Application to a pharmacokinetic study
Wang SHIXIAO ; Wang YANG ; Gao SHUANG ; Zhang YUANYUAN ; Wang HANPEI ; Zhao LONGSHAN ; Bi KAISHUN ; Wang SHAOJIE ; Chen XIAOHUI
Journal of Pharmaceutical Analysis 2017;7(6):406-410
A simple, rapid and sensitive method based on an ultra-performance liquid chromatography–tandem mass spectrometry(UPLC–MS/MS)has been developed and validated for the determination of pimavanserin in rat plasma.The analyte was extracted by protein precipitation with methanol and separated on an ACQUITY BEH C18column(100 mm×2.1 mm,1.7μm;Waters,USA),with an isocratic elution of acetonitrile-water containing 10 mM ammonium acetate (70:30, v/v), at a flow rate of 0.2 mL/min for 2.5 min. The analyte and clarithromycin (the internal standard) were detected and quantified in positive ion mode using multiple reaction monitoring transitions at m/z 428.2 → 223.0 for pimavanserin and m/z 748.5 → 589.5 for clarithromycin. Relative coefficient (r) for the calibration curve was more than 0.9980. The intra-day and inter-day precisions(relative standard deviation,RSD%)were less than 13.3% and 10.5%,respectively,and the accuracy(relative error,RE%)was within ± 11.5%.The analytical method was successfully applied to a routine pharmacokinetic study of pimavanserin in rats after oral administration at the dose of 10 mg/kg.
5.Characteristics of neonatal neuroblastoma: analysis of 14 cases
Lei LIU ; Shixiao DONG ; Jingwen WENG ; Mingyan HEI ; Yajuan WANG ; Jiaoyang CHEN ; Yingzi LI
Chinese Journal of Perinatal Medicine 2020;23(9):608-614
Objective:To analyze the diagnosis and treatment of neonatal neuroblastoma (NB) by summarizing its clinical characteristics.Methods:This study retrospectively recruited 14 neonates with NB in Beijing Children's Hospital (National Center for Children's Health) from February 1, 2015, to February 1, 2020. Medical records and follow-up data as of February 29, 2020, were collected, and clinical staging based on International Neuroblastoma Staging System, risk grouping based on American Childhood Oncology Group risk grouping system, diagnosis, treatment, and prognosis were analyzed. According to whether surgical treatment was performed in the neonatal period or not, these subjects were divided into surgical and non-surgical groups. A descriptive statistical analysis was used for data analysis.Results:(1) Neonates with NB accounted for 0.063% (14/22 006) of the total number of newborns admitted to the hospital during the same period. The 14 cases were all full-term aged 15 d (8 h-23 d) at admission. Tumors were found in seven cases in prenatal examinations, while others presented with shortness of breath (three cases), abdominal distension (two cases), fever (one case), and dysuria and difficult defecation after birth (one case). (2) The primary tumor sites included the adrenal gland (eight cases), posterior mediastinum (three cases), retroperitoneum (two cases), and sacrococcygeal (one case). Three cases had extensive diffuse liver metastasis at admission. (3) Except for two cases who refused to examine, the serum neuron-specific enolase of 12 cases was 57.2 ng/ml (35.9-158.3 ng/ml) during hospitalization, and the urine vanillyl-mandelic acid creatinine of four cases was 2 304.940 (685.748-9 595.314). (4) Primary tumor sites were found in 14 cases by imaging examination. Bone scanning was performed in three cases, including one with a concentrated shadow of the right sacroiliac joint and two with no abnormalities. Ten cases underwent bone marrow aspiration and all with normal results. (5) Of the ten neonates received surgery (the surgical group), nine had the primary tumor wholly removed, without chemotherapy after the operation, and the tumor-free survival period was 19 months (1-45 months). One case (case 5) had a substantial primary tumor that could not be completely resected. The patient underwent a second surgery five months after the first operation due to disease progression and received postoperative chemotherapy. The child had stopped chemotherapy for 24 months and survived without a tumor. (6) In the non-surgical group (cases 11 to 14), the tumor in case 11 who refused chemotherapy shrank spontaneously after discharge, and the patient survived for 20 months with the tumor. The parents of the case 12 withdrew treatment during hospitalization, while the primary tumor and metastases disappeared after discharge, and the specific tumor markers gradually decreased to normal levels. The patient has been tumor-free survived for 25 months. Case 13 received mediastinal tumor resection and chemotherapy during infancy. At the end of the follow-up, chemotherapy had been stopped for 12 months, and the patient survived without a tumor. Case 14 withdrew treatment and died. (7) Among the ten cases in the surgical group, one patient's pathological result indicated a composite tumor, while the others were low differentiated neuroblastoma. There was no MYCN gene amplification, 1p36 deletion, or 11q23 deletion in the ten cases. (8) Among the ten children in the surgical group, nine were in stage 1, and one was in stage 4S (case 5). Nine cases were classified into extremely low-risk groups, while the other was in the low-risk group. The four cases in the non-surgical group could not be grouped by risk. Conclusions:Clinical manifestations of neonatal NB are often atypical. NB in stage 4S might resolve spontaneously, and expectant observation may be considered. The overall prognosis of neonatal NB is generally good, but further researches are needed.
6.Molecular basis of Del phenotype in RhD negative population of Zhongshan
Yonggao CHEN ; Shaomei WU ; Bing YI ; Shixiao LAI
Chinese Journal of Blood Transfusion 2022;35(2):157-161
【Objective】 To conduct serological and molecular study of Del type in RhD-negative donor population in Zhongshan area, so as to improve the diagnosis of Del type. 【Methods】 A total of 102 initially RhD-negative samples, collected from December 2017 to February 2019, were classified by RHCE and PCR-SSP genotyping. And 95 cases of truly negative RhD were confirmed by IAT, 28 cases of Del type were identified by absorption and elution test. The phenotype and genotyping characteristics of Del type in Zhongshan area were summarized based on domestic data of relative literature. 【Results】 Among 102 initially RhD-negative samples by serological test, 95 were truely RhD-negative, 28 were DELRHD 1227A without any other Del allele. Among them, RHCE antigen type were Ccee in 20(71.4%) cases, CCee in 8(28.6%), with no difference in comparison with other regions in China. The frequency of Del in RhD-negative blood donors was 29.5% (28/95), with difference between Shanghai, Taiwan, and Fuzhou, but no difference between Nanchang, Zhejiang, and Wuhan. 【Conclusion】 The study showed that the Del phenotype was closely related to Ce haplotype, and has no difference with other regions in China. The frequency of Del type in RhD negative donors was 29.5%, with regional differences. RHD1227A was the main allele of Del.
7.Establishment of prognostic model for severe primary graft dysfunction in patients with idiopathic pulmonary fibrosis after lung transplantation
Zhiyun SONG ; Taoyin DAI ; Sijia GU ; Xiaoshan LI ; Murong HUANG ; Shixiao TANG ; Chunxiao HU ; Jingyu CHEN
Organ Transplantation 2024;15(4):591-598
Objective To explore the establishment of a prognostic model based on machine learning algorithm to predict primary graft dysfunction(PGD)in patients with idiopathic pulmonary fibrosis(IPF)after lung transplantation.Methods Clinical data of 226 IPF patients who underwent lung transplantation were retrospectively analyzed.All patients were randomly divided into the training and test sets at a ratio of 7∶3.Using regularized logistic regression,random forest,support vector machine and artificial neural network,the prognostic model was established through variable screening,model establishment and model optimization.The performance of this prognostic model was assessed by the area under the receiver operating characteristic curve(AUC),positive predictive value,negative predictive value and accuracy.Results Sixteen key features were selected for model establishment.The AUC of the four prognostic models all exceeded 0.7.DeLong and McNemar tests found no significant difference in the performance among different models(both P>0.05).Conclusions Based on four machine learning algorithms,the prognostic model for grade 3 PGD after lung transplantation is preliminarily established.The overall prediction performance of each model is similar,which may predict the risk of grade 3 PGD in IPF patients after lung transplantation.