3.Recent Development of Droplet Microfluidics in Digital Polymerase Chain Reaction
Yiqiang FAN ; Mei WANG ; Feng GAO ; Jian ZHUANG ; Gang TANG ; Yajun ZHANG
Chinese Journal of Analytical Chemistry 2016;(8):1300-1307
Digital polymerase chain reaction ( PCR) has been experiencing a rapid development during the past few years. Comparing with the traditional real-time quantitative PCR ( RT-qPCR) , using the same primer and probe, the accuracy for the absolute quantification of target gene is significantly improved. The development of digital PCR is directly related to the development of microfluidics. The integrated fluid circuit is an early combination of the microfluidics and digital PCR, which has a complicated fabrication process with high cost. Recently, researchers are trying to apply the droplet microfluidics in digital PCR, and the droplet microfluidic chip is able to generate millions of droplets within a short time. Each of these droplets containing no more than one target gene is a reaction chamber during the amplification process. After amplification, each droplet is tested to achieve the absolute quantification of the target gene. This paper reviews the recent progresses of droplet digital PCR, and the applications of droplet digital PCR in biological, medical and environmental fields.
4.Prognosis of acute kidney injury requiring renal replacement therapy in patients undergoing surgery for Stanford type A aortic dissection
Xiaomei YANG ; Lan LIU ; Yamin ZHUANG ; Ying ZHANG ; Hua LIU ; Jian GAO ; Chunsheng WANG
Chinese Journal of Thoracic and Cardiovascular Surgery 2014;30(6):346-349
Objective Acute kidney injury(AKI) is a common and serious complication with high morbidity and mortality in patients undergoing surgery for Stanford type A aortic dissection.The purpose of this study is to investigate the mortality and risk factors for the prognosis of AKI requiring renal replacement therapy(RRT) in patients undergoing surgery for Stanford type A aortic dissection.Methods We retrospectively investigated 68 patients of AKI requiring RRT undergoing surgery for Stanford type A aortic dissection in Zhongshan Hospital from October 2005 to May 2013.The mean age was (55.31 ± 11.08) years.The patients were divided into two groups,survivors(n =40) and non-survivors(n =28).We observed the clinical data of the patients in both groups.Univariate and multivariate analyses were performed to investigate the risk factors for prognosis of AKI requiring RRT.Results Of the 68 patients,28 patients died.The in-hospital mortality was 41.18%.Univariate analysis showed the following as significant risk factors:APACHE Ⅱ score,hypotension,gastrointestinal bleeding,hepatic dysfunction,neurological deficits(P < 0.05).Multivariable Cox regression analysis identified New York Heart Association (NYHA) functional class Ⅳ (HR 5.486,95 % CI 1.805-16.676),APACHE Ⅱ score (HR 1.123,95% CI 1.055-1.196),hypotension (HR 3.328,95% CI 1.180-9.382),hepatic dysfunction(HR 2.242,95% CI 1.015-4.952) were independent predictors of in-hospital mortality (P < 0.05).Conclusion AKI requiring RRT after Stanford type A aortic dissection surgery is associated with high mortality.Risk factors of death should be taken into consideration for perioperative care and may improve clinical outcome.
5.Risk factors for acute kidney injury after adult cardiac surgery with cardiopulmonary bypass
Xiaomei YANG ; Chunsheng WANG ; Lan LIU ; Ying ZHANG ; Yamin ZHUANG ; Hua LIU ; Jian GAO
Chinese Journal of Thoracic and Cardiovascular Surgery 2013;(3):147-150
Objective To investigate the incidence and risk factors for acute kidney injury (AKI) after adult cardiac surgery with cardiopulmonary bypass.Methods 6665 adult patients who underwent cardiac surgery with cardiopulmonary bypass in Zhongshan Hospital from September 2006 to July 2011 were analyzed retrospectively.The patients were divided into two groups according to whether AKI occurred after cardiac surgery.We observed the clinical data of the patients in both groups.The risk factors for AKI after operation were evaluated by Univariate analyses and multivariate logistic regression analysis.Results Of the 6665 patients,AKI developed in 1779 (26.69%) patients,whereas 102 (1.53%) had renal replacement therapy.Patients with AKI had significant higher mortality than patients without AKI (2.47% vs.0.29%,P <0.0l).Multivariate logistic regression analysis revealed that male,increased age,hypertension,diabetes,preoperative serum creatinine (≥ 115 μmol/L),preoperative uric acid(≥420 μmol/L),low preoperative left ventricular ejection fraction(< 0.40),preoperative anemia,type of surgery(aortic aneurysm surgery),long cardiopulmonary bypass time(≥ 120 min),requirement of deep hypothermic circulatory arrest,postoperative hypotension,blood transfusion within 24 h after operation (≥ 1000 ml),prolonged mechanical ventilation time (≥ 72 h) were the independent risk factors for AKI in post cardiac surgical patients.Conclusion AKI is a common complication in adult undergoing cardiac surgery with cardiopulmonary bypass,and associated with an increased mortality.The development of AKI is closed related with variety perioperative risk factors,suggesting more attention should be paid to the assessment and prevention of these risk factors.
6.Recent Development of Wearable Microfluidics Applied in Body Fluid Testing and Drug Delivery
Yiqiang FAN ; Feng GAO ; Mei WANG ; Jian ZHUANG ; Gang TANG ; Yajun ZHANG
Chinese Journal of Analytical Chemistry 2017;45(3):455-463
wearable microfluidics have wide applications in medical, sports and military field. with the help of wearable microfluidics, through the direct physical contact between the chip and skin, the pH, glucose, lactate, sodium/potassium, calcium and heavy metal in the body fluid can be detected from sweat, tear and saliva without puncture for blood. And these information are of great importance for the monitoring of vital signs and disease diagnosis. This paper introduced the most recent development and applications of the wearable microfluidics in the body fluid testing and drug delivery. The up-to-date research development for the drug delivery using wearable microfluidics was also briefly introduced in this article. The forecast of the emerging trend for wearable microfluidics and discussion of potential technique barriers was also provided at the end of this article.
7.Protection of endogenous erythropoietin on photoreceptor cells in retinal detachment and its mechanism
Zheng-gao, XIE ; Fang, CHEN ; Chao-rong ZHUANG ; Jian, WANG ; Xin, HUA ; Hong, WANG ; He-qing, JI
Chinese Journal of Experimental Ophthalmology 2011;29(7):605-609
Background Erythropoietin (EPO) has a protective effect on retinal neurons in many retinal diseases,but regarding the effect of EPO on apoptosis of retinal photoreceptor cells in retinal detachment (RD) is uncompletely clear.Objective This study was to investigate the protective effect of endogenous EPO on photoreceptors in a rat model of RD and explore its possible mechanism.Methods Seventy-two Sprague- Dawley (SD) rats were randomly assigned to control group,RD group,RD+PBS group,RD+erythropoietin soluble receptor (EPOsR) 2, 20, 200ng groups with 12 rats for each group.1.4% hyaluronic acid was slowly injected into the subretinal space to induce RD in rats,and PBS or 2,20 or 200ng EPOsR was then injected into the vitreous space.On day 3 after RD,apoptotic photoreceptors were detected using transferase-mediated dUTP nickend labeling (TUNEL),and caspase-3 activity was assessed by Western-blot and immunofluorescence staining.On day 14 after RD,retinal histopathologic examination was carried out and outer nuclear layer (ONL) thickness was measured under the light microscope.The use of animals complied with the Statement of Association for Research in Vision and Ophthalmology. Results Apoptotic photoreceptors were seen in ONL of rats of the RD group.Apoptotic photoreceptors were gradually increased with the elevation of EPOsR dose in the vitreous cavity.Western blot and immunofluorescence consistently showed that the gray scale of caspase-3 activity was 0.15±0.04,0.49±0.03,0.50±0.07,0.63±0.03,0.69±0.04 and 0.83±0.04 in the normal group,RD group,RD +PBS group,RD+EPOsR 2,20,200ng groups respectively with statistically significant differences (F=76.016;P=0.000),and caspase-3 activity was considerably stronger in the RD+EPOsR 200ng group than the other groups (P<0.01).On day 14 after RD,the ONL thicknesses in the normal control group,RD group,RD+PBS group,RD+EPOsR 2,20,200ng groups were (47.39±3.39)μm,(33.96±3.54)μm,(31.83±5.21)μm,(31.40±2.63)μm,(24.99±2.06)μm and (19.30±3.71)μm,showing significant differences among these groups (F=44.733,P=0.000).ONL thicknesses the groups treated with different doses of EPOsR were markedly thinner than that of the RD group and RD +PBS group (P<0.01).Conclusion EPOsR induces apoptosis of retinal cells and enhances the activity of caspase-3 in a dose-dependent manner.Endogenous EPO can protect photoreceptors against anoxia-mediated damage in RD eyes through decreasing caspase-3 activity and inhibiting apoptosis.
8.Effect of erythropoietin on signal transduction pathway in rat model of retinal detachment
Zheng-gao, XIE ; Fang, CHEN ; Chao-rong, ZHUANG ; Jian, WANG ; Hong, WANG ; Ya-kun, WANG ; Jun, ZHU
Chinese Journal of Experimental Ophthalmology 2012;30(2):141-145
BackgroundOur previous study showed that erythropoietin (EPO) protects the photoreceptor from apoptosis in retinal detachment(RD) rat,but its signal transduction pathway remains unknown.Objective The present study was to investigate the effects of EPO on signal transduction pathway in RD.MethodsTwentyfour albino clean Sprague-Dawley(SD) rats were randomly divided into 4 groups.5 μl PBS was injected into vitreous cavity of rats in RD+PBS group,and 400 ng EPO(5 μl) was used at the same way in RD+EPO group.Three days later,the rats were sacrificed and the retina was isolated in each group.The expression levels of Janus kinase 2 (JAK2),p-JAK2,Akt,p-Akt,extracellular regulated protein kinase-1/2 ( ERK-1/2 ),p-ERK-1/2,signal transducer and activator of transcription 5 ( STAT5 ),p-STAT5,nuclear factor-kB (NF-sB) and p-NF-kB were detected by Western blot assay.The administration of experimental animals followed the Standard of ARVO.ResultsThree days after RD,the expression levels of JAK2,Akt and ERK-1,ERK-2 in retinas among normal group,RD,RD+PBS,RD+EPO groups were statistically insignificant different ( F =0.298,P =0.826 ; F =0.681,P =0.588 ; F =0.978,P=0.450;F=1.115,P=0.399 ),but the levels of p-JAK2,p-Akt,p-Erk-1 and p-Erk-2 among these 4 groups were significant difference ( F=24.435,P =0.000; F=48.163,P =0.000;F =19.092,P =0.001; F =14.393,P=0.001 ),and those in RD+EPO group was significantly higher than that in RD and RD+PBS groups( P<0.05 ).The expression levels of STAT5 and NF-kB among the 4 groups were no significantly differences (F =1.136,P=0.391 ;F=0.696,P=0.580),but after the phosphorylation of STAT5 and NF-kB,the differences was significant ( F =14.189,P =0.001 ; F =40.103,P =0.000 ).Those in RD,RD + PBS,RD + EPO groups did not increase either (P>0.05).Although the levels of p-STAT5 and p-NF-kB in RD,RD+PBS,RD+EPO groups were significantly higher than those in normal control group( P<0.05 ),the level of p-STAT5 in RD+EPO group was not significantly higher than that in RD and RD + PBS groups (P > 0.05 ). Conclusions PI3K/Akt and MAPK/ERK-1/2 signal transduction pathways might participate in the protecting process of EPO to photoreceptor in RD rats.
10.Study on the differences of risk factors regarding congenital heart defects between floating population and permanent residents in Guangdong.
Yan-qiu OU ; Zhi-qiang NIE ; Xiao-qing LIU ; Jin-zhuang MAI ; Yong WU ; Xiang-min GAO ; Jian ZHUANG ; Ji-mei CHEN
Chinese Journal of Epidemiology 2013;34(7):701-705
OBJECTIVETo analyze the differences of risk factors on congenital heart defect (CHD)between floating population and permanent residents in Guangdong.
METHODSA multicenter case-control study was carried out to investigate the risk factors of CHD in floating population and in permanent residents. Data was from 34 Guangdong CHD Monitoring Network centers during the year of 2004 to 2011. Exposed information related to the parents at pre-pregnancy and early pregnancy periods, was collected, using the same questionnaire survey methodology in the two populations. Possible risk factors were analyzed by univariate analysis and multivariate non-conditional logistic regression(ENTER method)methods. Risk factors were compared between the two populations.
RESULTSTotally, 855 CHD cases and their controls from the floating population, as well as 1673 cases and their controls from the permanent residents were included in this study. Age of the children under study was defined from 28th week of gestation to 1 year old postnatal. In the floating population, specific risk factor for CHD appeared as:maternal passive smoking in early pregnancy, while the specific protective factor as high family income. However, the specific risk factors would include: having diseases as maternal diabetes mellitus or syphilis, living in a newly (within half a year) decorated house or with fetal macrosomia in the permanent residents. High education level showed as a risk factor in floating population, however contrarily, as protective factor to the permanent residents. Except for the factors related to having fever of the mother and infant with low birth weight, factors as having history of deliveries more than two, with maternal virus infection, exposure to chemical agent and negative bearing history etc., have higher OR values in floating population than in the permanent residents.
CONCLUSIONSignificant differences of risk factors for CHD were noticed between floating population and the permanent residents, which have their individual specific risk factors. Most of the ORs appeared higher in floating population than in the permanent residents.
Case-Control Studies ; China ; epidemiology ; Female ; Heart Defects, Congenital ; epidemiology ; Humans ; Infant ; Infant, Newborn ; Male ; Transients and Migrants