Zhi Zheng

Shanghai Jiao Tong University, Shanghai, Shanghai Shi, China

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Publications (44)98.9 Total impact

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    Min Tang · Yang Fu · Ying Wang · Zhi Zheng · Ying Fan · Xiaodong Sun · Xun Xu
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    ABSTRACT: Neovascular glaucoma is a refractive glaucoma. Recently, anti-VEGF factors have been used alone or in combination for the treatment of neovascular glaucoma. However, the medium- and long-term efficacy of such drugs remains to be evaluated. This study was to determine the efficacy of intravitreal ranibizumab combined with Ahmed glaucoma valve implantation for the treatment of neovascular glaucoma. In this prospective non-randomized study, 43 neovascular glaucoma patients (43 eyes) were assigned to receive either 0.5 mg intravitreal ranibizumab for three to 14 days before Ahmed glaucoma valve implantation (injection group, n = 21) or Ahmed glaucoma valve implantation alone (control group, n = 22). The patients were followed up for six to 12 months. Differences in surgical success rate, intraocular pressure, best corrected visual acuity, anti-glaucoma medications and postoperative complications were compared between the two groups. Surgical success was defined as IOP > = 6 mm Hg and < = 21 mm Hg, with or without the use of anti-glaucoma medications, and without severe complications or reoperation. Of the 43 patients, 40 completed the 6-month follow-up and 37 completed the 1-year follow-up. Success rate was 73.7 % vs. 71.4 % at six months and 72.2 % vs. 68.4 % at 12 months in the injection group and the control group respectively. No significant difference was noted between the two groups (six months: P = 0.87, 12 months: P = 1.00). There were no significant differences in the two groups with respect to intraocular pressure, best corrected visual acuity, anti-glaucoma medications or postoperative complications at six months or 12 months. Single intravitreal ranibizumab (0.5 mg) before surgery has no significant effect on the medium- or long-term outcomes of neovascular glaucoma treated with Ahmed glaucoma valve implantation. Trial registration Chinese Clinical Trial Registry (ChiCTR-OOC-14005709, Trial registration date: 2014-12-01)
    Preview · Article · Jan 2016 · BMC Ophthalmology
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    ABSTRACT: Aims/hypothesis: The mechanisms underlying the cellular metabolic memory induced by high glucose remain unclear. Here, we sought to determine the effects of microRNAs (miRNAs) on metabolic memory in diabetic retinopathy. Methods: The miRNA microarray was used to examine human retinal endothelial cells (HRECs) following exposure to normal glucose (N) or high glucose (H) for 1 week or transient H for 2 days followed by N for another 5 days (H→N). Levels of sirtuin 1 (SIRT1) and acetylated-nuclear factor κB (Ac-NF-κB) were examined following transfection with miR-23b-3p inhibitor or with SIRT1 small interfering (si)RNA in the H→N group, and the apoptotic HRECs were determined by flow cytometry. Retinal tissues from diabetic rats were similarly studied following intravitreal injection of miR-23b-3p inhibitor. Chromatin immunoprecipitation (ChIP) analysis was performed to detect binding of NF-κB p65 to the potential binding site of the miR-23b-27b-24-1 gene promoter in HRECs. Results: High glucose increased miR-23b-3p expression, even after the return to normal glucose. Luciferase assays identified SIRT1 as a target mRNA of miR-23b-3p. Reduced miR-23b-3p expression inhibited Ac-NF-κB expression by rescuing SIRT1 expression and also relieved the effect of metabolic memory induced by high glucose in HRECs. The results were confirmed in the retina using a diabetic rat model of metabolic memory. High glucose facilitated the recruitment of NF-κB p65 and promoted transcription of the miR-23b-27b-24-1 gene, which can be suppressed by decreasing miR-23b-3p expression. Conclusions/interpretation: These studies identify a novel mechanism whereby miR-23b-3p regulates high-glucose-induced cellular metabolic memory in diabetic retinopathy through a SIRT1-dependent signalling pathway.
    No preview · Article · Dec 2015 · Diabetologia
  • Jian Gao · Zhi Zheng · Qing Gu · Xia Chen · Xiaoxiao Liu · Xun Xu
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    ABSTRACT: A key initiator in the development of diabetic retinopathy is considered to be the production of reative oxygen species (ROS) in the retinal mitochondria, and their scavenging enzyme, manganese superoxide dismutase (MnSOD), is compromised. However, the mechanism by which high glucose regulates MnSOD is unclear. In this study, we found that a high concentration of glucose inhibited the expression of the histone deacetylase SIRT3, which resulted in a reduction in MnSOD activity in bovine retinal capillary endothelial cells and in the retinas of diabetic rats. Conversely, SIRT3 overexpression attenuated hyperglycemic stress through deacetylation and activationof MnSOD. Furthermore, the hyperglycemia-induced downregulation of SIRT3 involved the activation of poly (ADP-ribose) polymerase (PARP). Our study is the first to link the deacetylation of MnSOD by PARP-regulated SIRT3 with the pathogenesis of diabetic retinopathy. Understanding the role of SIRT3 in the pathogenesis of diabetic retinopathy could help elucidate key molecular targets for future pharmacological interventions.
    No preview · Article · Dec 2015 · Biochemical and Biophysical Research Communications
  • Qianyi Lu · Wenjun Zou · Bin Chen · Chen Zou · Minjie Zhao · Zhi Zheng
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    ABSTRACT: Purpose: To investigate the relationship between angiopoietin-like protein 4 (ANGPTL-4) and vascular endothelial growth factor (VEGF) in the serum and vitreous of eyes in patients with proliferative diabetic retinopathy (PDR). Methods: Thirty-five eyes of 35 patients with PDR, 20 eyes of 20 patients with non-proliferative diabetic retinopathy, 20 eyes of 20 patients with diabetes but no diabetic retinopathy, and 14 eyes of 14 nondiabetic patients with an idiopathic macular hole (IMH) were recruited from Shanghai First People's Hospital. The ANGPTL-4 and VEGF concentrations were determined using enzyme-linked immunosorbent assays. Group means were compared using one-way analysis of variance with GraphPad Prism 4.0 and SPSS ver. 17.0. The research followed the tenets of the Declaration of Helsinki. Results: The ANGPTL-4 and VEGF levels were significantly higher in the vitreous and serum of patients with PDR compared with patients with IMH. There were significant correlations between the ANGPTL-4 and VEGF levels in the vitreous and serum of patients with PDR. The vitreous and serum ANGPTL-4 levels were also significantly correlated in patients with PDR. The ANGPTL-4 in both the vitreous and serum correlated with the serum triglyceride and high-density lipoprotein cholesterol levels. Conclusions: The ANGPTL-4 levels were markedly elevated and the ANGPTL-4 expression was directly correlated with the VEGF expression in the vitreous and serum of patients with PDR. The vitreous and serum ANGPTL-4 levels were also significantly correlated with serum lipids in patients with PDR. Our results suggest that the ANGPTL-4 may be used as a new therapeutic target for the treatment of PDR.
    No preview · Article · Oct 2015 · Albrecht von Graæes Archiv für Ophthalmologie
  • Shuzhi Zhao · Jun Li · Na Wang · Bingqing Zheng · Tao Li · Qing Gu · Xun Xu · Zhi Zheng
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    ABSTRACT: Inflammation is a major contributing factor in the development of diabetic microvascular complications, regardless of whether improved glycaemic control is achieved. Studies have increasingly indicated that fenofibrate, a lipid‑lowering therapeutic agent in clinical use, exerts a potential anti‑inflammatory effect, which is mediated by sirtuin 1 (SIRT1; an NAD+‑dependent deacetylase) in endothelial cells. The aim of the present study was to investigate the inhibitory effect of fenofibrate on metabolic memory (via the regulation of SIRT1), and inflammatory responses in cell and animal models of diabetic retinopathy (DR). The data demonstrated that high glucose treatment in human retinal endothelial cells (HRECs) inhibited the expression and deacetylase activity of SIRT1. The reduction of SIRT1 expression and deacetylase activity persisted following a return to normal glucose levels. Furthermore, nuclear factor‑κB expression was observed to be negatively correlated with SIRT1 expression and activity in HRECs under high glucose levels and the subsequent return to normal glucose levels. Fenofibrate treatment abrogated these changes. Knockdown of SIRT1 attenuated the effect of fenofibrate on high glucose‑induced NF‑κB expression. In addition, fenofibrate upregulated SIRT1 expression through peroxisome proliferator‑activated receptor α in high glucose‑induced metabolic memory. These findings indicate that fenofibrate is important in anti‑inflammatory processes and suppresses the cellular metabolic memory of high glucose‑induced stress via the SIRT1‑dependent signalling pathway. Thus, treatment with fenofibrate may offer a promising therapeutic strategy for halting the development of DR and other complications of diabetes.
    No preview · Article · Jul 2015 · Molecular Medicine Reports
  • Qianyi Lu · Li Lu · Wei Chen · Haibing Chen · Xun Xu · Zhi Zheng
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    ABSTRACT: Diabetic retinopathy (DR) is a major cause of blindness in the working-age populations of developed countries, and effective treatments and prevention measures have long been the foci of study. Patients with DR invariably demonstrate impairments of the retinal microvascular endothelium. Many observational and preclinical studies have shown that angiogenesis and apoptosis play crucial roles in the pathogenesis of DR. Increasing evidence suggests that in DR, the small guanosine-5'-triphosphate-binding protein RhoA activates its downstream targets mammalian Diaphanous homolog 1 (mDia-1) and profilin-1, thus affecting important cellular functions, including cell morphology, motility, secretion, proliferation, and gene expression. However, the specific underlying mechanism of disease remains unclear. This review focuses on the RhoA/mDia-1/profilin-1 signaling pathway that specifically triggers endothelial dysfunction in diabetic patients. Recently, RhoA and profilin-1 signaling has attracted a great deal of attention in the context of diabetes-related research. However, the precise molecular mechanism by which the RhoA/mDia-1/profilin-1 pathway is involved in progression of microvascular endothelial dysfunction (MVED) during DR has not been determined. This review briefly describes each feature of the cascade before exploring the most recent findings on how the pathway may trigger endothelial dysfunction in DR. When the underlying mechanisms are understood, novel therapies seeking to restore the endothelial homeostasis comprised in DR will become possible.
    No preview · Article · Mar 2015 · Albrecht von Graæes Archiv für Ophthalmologie
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    ABSTRACT: A thin and flexible paper-based skin patch was developed for the diagnostic screening of Cystic Fibrosis. It utilized a unique combination of anion exchange and pH testing papers to enable a quantitative, colorimetric and on-skin detection for sweat anions.
    Full-text · Article · Mar 2015 · Chemical Communications
  • Chuandi Zhou · Qinghua Qiu · Zhi Zheng
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    ABSTRACT: To compare the efficacy of air and octafluoropropane (C3F8) in treating rhegmatogenous retinal detachments with inferior breaks after 23-gauge pars plana vitrectomy. A prospective, randomized comparative interventional study. Sixty-four patients with rhegmatogenous retinal detachment with inferior breaks underwent pars plana vitrectomy with air (32 eyes) or gas (32 eyes) tamponade. Anatomical and visual outcomes of the two groups were compared. The mean follow-up period was 13.09 ± 1.90 months. Significant differences were identified regarding prone positioning period (P < 0.01), intraocular pressure (P < 0.01), and gas volume (P = 0.03) on the first postoperative day. The single-operation success rates for the air and gas groups were 84.38% and 78.13% (P = 0.522), and the final surgery success rates increased to 100% and 96.88% (P = 0.313), respectively. The single-operation success rate between the groups was not statistically significant, even after adjustment for confounding factors. Multivariate logistic regression also indicated that the number of involved retinal quadrants (odds ratio = 19.88, P = 0.01) was an independent predictor of surgery failure. The only postoperative complication observed was new or missed breaks, which occurred in 12 patients (18.75%). Air had equivalent tamponade effects to C3F8, with a shorter prone positioning period, fewer complications, and less expense, in the surgical management of rhegmatogenous retinal detachment with inferior breaks.
    No preview · Article · Jan 2015 · Retina (Philadelphia, Pa.)
  • Zhi Zheng · Guojun Guo · Li Xu · Lei Lei · Xiang Wei · Youmin Pan
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    ABSTRACT: The aim of this study was to evaluate the embolic sequelae of left atrial myxomas and their influence on diagnosis, treatment, and prognosis. Seventy-eight patients were retrospectively investigated. According to their symptoms and neurologic-imaging findings, these patients were classified into 2 groups: embolism (15 patients, 19%) and nonembolism (63 patients, 81%). The time from the first onset of symptoms to diagnosis (that is, the duration of symptoms) was significantly longer in the embolism group than in the nonembolism group (105 ± 190 vs 23 ± 18 d; P <0.01). The myxomas were divided into 2 types on the basis of clinicopathologic findings: type 1, with an irregular or villous surface and a soft consistency, and type 2, with a smooth surface and a compact consistency. There were 42 patients with type 1 myxoma and 36 with type 2. Type 1 myxoma was more frequently found in the embolism group (12 patients, 29%) than was type 2 myxoma (3 patients, 8%). The difference was significant (P=0.04). There were 2 perioperative deaths in the nonembolism group. No recurrence of cardiac myxoma or death was recorded in either group during follow-up. In the embolism group, neurologic symptoms were relieved by surgery, and no subsequent neurologic event was reported. Because surgical resection is highly effective in left atrial myxoma, we should strive for early diagnosis in order to shorten the duration of symptoms and to avoid worse neurologic damage in patients in whom an embolic event is the initial manifestation.
    No preview · Article · Dec 2014 · Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital
  • Qian-Yi Lu · Wei Chen · Li Lu · Zhi Zheng · Xun Xu
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    ABSTRACT: Diabetic retinopathy (DR) is a well-known serious complication of diabetes mellitus (DM), and can eventually advance to end-stage blindness. In the early stage of DR, endothelial cell barrier disorganized primarily and tight junction (TJ) protein composition transformed subsequently. The small GTPase RhoA and its downstream effector Rho-associated coiled-coil containing protein kinase 1 (ROCK1) regulate a mass of cellular processes, including cell adherence, proliferation, permeability and apoptosis. Although RhoA inhibitors have provided substantial clinical benefit as hypertonicity therapeutics, their use is limited by complex microenvironment as DR. While ample evidence indicates that TJ can be influenced by the RhoA/ROCK1 signaling, the underlying mechanisms remain incompletely understood. Here, we have uncovered a significant signaling network involved in diabetic retinal microvascular endothelial dysfunction (RMVED). Our results indicated that the activation of RhoA/ROCK1 pathway due to high glucose played a key role in microvascular endothelial cell dysfunction (MVED) by way of directly inducing TJ proteins over-expression during DR. We demonstrated that inhibition of RhoA/ROCK1 may attenuate the hypertonicity of endothelial cell caused by high glucose microenvironment meanwhile. Besides, chemical and pharmacological inhibitors of RhoA/ROCK1 pathway may partly block inflammation due to DR. Simultaneously, the apoptosis aroused by high glucose was also prevented considerably by fasudil, a kind of pharmacological inhibitor of RhoA/ROCK1 pathway. These findings indicate that RhoA/ROCK1 signaling directly modulates MVED, suggesting a novel therapeutic target for DR.
    No preview · Article · Nov 2014 · International journal of clinical and experimental pathology
  • Wei Chen · Hui Cao · Qian-Yi Lu · Na Wang · Shu-Zhi Zhao · Xun Xu · Zhi Zheng
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    ABSTRACT: Melatonin is a powerful antioxidant. Decreased melatonin excretion has been reported to be associated with several oxidative stress-related diseases. The urinary metabolite of melatonin, 6-sulfatoxymelatonin (aMT6s), has proved to be a very reliable index of melatonin production. The present study aims to evaluate the level of urinary aMT6s in patients with type 2 diabetes mellitus and diabetic retinopathy. Urine samples were collected from 10 patients with diabetes and no diabetic retinopathy (NDR), 19 patients with nonproliferative diabetic retinopathy (NPDR), 38 patients with proliferative diabetic retinopathy (PDR), and 16 subjects without diabetes mellitus, who served as controls. The level of aMT6s in specimens was assayed by a commercial aMT6s ELISA kit, creatinine levels were also measured for each sample to get urinary aMT6s/creatinine ratio. Creatinine-adjusted urinary aMT6s values were compared among four groups. The urinary aMT6s (mean ± SD) levels were 9.95 ± 2.42, 9.90 ± 2.28, 8.40 ± 1.84 and 5.58 ± 1.33 ng/mg creatinine in the controls and in patients with NDR, NPDR, or PDR, respectively. The urinary aMT6s level of the PDR group was significantly lower than that of the control, NDR and DR groups. No significant difference was found among the control, NDR and DR groups. After adjustment for various factors (age, smoking, cancer, and coronary heart disease) that may influence the aMT6s level, the odds-ratio of urinary aMT6s comparing PDR patients to controls was 0.246 (95% confidence interval = 0.108-0.558, P = 0.001). Therefore, the urinary aMT6s level is significantly decreased in diabetic patients with PDR but not in diabetic patients without PDR, which indicates that decreased urinary aMT6s level may be associated with the pathogenesis of PDR.
    No preview · Article · Aug 2014 · International journal of clinical and experimental pathology
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    ABSTRACT: Objective: Purpose of this study was to validate that Subtenon (SB) Triamcinolone (TA) injection is an alternative to Intravitreal (IV) Triamcinolone (TA) injection for the treatment of diabetic macular edema (DME). Methods: Forty eyes were selected having DME due to type 1 or type 2 diabetes. All the patients were treated with photocoagulation. IVTA was administered in one eye and SBTA in following eye of same patient. Improvement in visual acuity, macular edema and intraocular pressure was assessed before treatment and on 2nd, 4th, 8th and 12th week after treatment. Results: After administration of IVTA, MVA was reduced from baseline value (0.805 ± 0.069Log/MAR) to (0.577 ± 0.091 Log/MAR, p<.001) at the end of treatment. Similar results were observed after SBTA administration. MVA was reduced from (0.814 ± 0.082Log/MAR) to (0.49 ± 0.080 Log/MAR, p<.001) at 12th week. After IVTA injection Central macular thickness was significantly reduced to (246.8 ± 25 µm, p<0.001) from (390.5 ± 17 µm). There were no significant (p=0.51) difference in both eyes receiving different routes of same treatment. After SBTA injection CMT was significantly reduced to lower values (241.5 ± 27 µm, p<0.001) from (394.4 ± 21 µm). Intraocular pressure after IVTA administration was high (2.32 ± 0.72 mm/Hg, p=0.04) as compared to baseline (1.82 ± 0.94 mm/Hg). Similar pattern was also seen after SBTA administration but to significant extent. Elevation of IoP was observed in both eyes. Conclusion: Subtenon Triamcinolone injection is an alternative to Intravitreal Triamcinolone Injection for Diabetic Macular Edema.
    Preview · Article · Jul 2014 · Pakistan Journal of Medical Sciences Online
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    Xuan Mu · Lin Zhang · Shaoying Chang · Wei Cui · Zhi Zheng
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    ABSTRACT: Hepatitis C virus (HCV) infection is a serious and rising global healthcare problem. One critical challenge to tackle this disease is the lack of adequate diagnosis. Here, we develop a multiplex microfluidic paper-based immunoassay, as a novel diagnostic approach, to detect human IgG antibody against HCV (anti-HCV). The paper substrate, highly flammable Nitrocellulose (NC), is patterned under ambient temperature by Craft Punch Patterning (CPP) to generate multiple test zones. On the basis of superior merits of patterned paper, this new diagnostic approach demonstrates the key novelty to unprecedentedly combine segmented diagnostic assays into a single multiplex test. The generated diagnostic results are not only informative, but can be rapidly and cost-effectively delivered. It would significantly transform clinical pathway for unwitting individuals with HCV infection. This work highlights the promising role of microfluidic paper-based immunoassay in tackling the diagnostic challenge for HCV pandemic as well as the innovation of diagnostics in other diseases.
    Full-text · Article · May 2014 · Analytical Chemistry
  • Wei Chen · Ying Wu · Mi Zheng · Qing Gu · Zhi Zheng · Xin Xia
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    ABSTRACT: To develop a reliable, reproducible rat model of retinal vein occlusion (RVO) with a novel photosensitizer (erythrosin B) and study the cellular responses in the retina. Central and branch RVOs were created in adult male rats via photochemically-induced ischemia. Retinal changes were monitored via color fundus photography and fluorescein angiography at 1 and 3h, and 1, 4, 7, 14, and 21d after irradiation. Tissue slices were evaluated histopathologically. Retinal ganglion cell survival at different times after RVO induction was quantified by nuclear density count. Retinal thickness was also observed. For all rats in both the central and branch RVO groups, blood flow ceased immediately after laser irradiation and retinal edema was evident at one hour. The retinal detachment rate was 100% at 3h and developed into bullous retinal detachment within 24h. Retinal hemorrhages were not observed until 24h. Clearance of the occluded veins at 7d was observed by fluorescein angiography. Disease manifestation in the central RVO eyes was more severe than in the branch RVO group. A remarkable reduction in the ganglion cell count and retinal thickness was observed in the central RVO group by 21d, whereas moderate changes occurred in the branch RVO group. Rat RVO created by photochemically-induced ischemia using erythrosin B is a reproducible and reliable animal model for mimicking the key features of human RVO. However, considering the 100% rate of retinal detachment, this animal model is more suitable for studying RVO with chronic retinal detachment.
    No preview · Article · Apr 2014 · International Journal of Ophthalmology
  • Ying He · Ning Wang · Yinchen Shen · Zhi Zheng · Xun Xu
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    ABSTRACT: Studies have shown that an overproduction of mitochondrial reactive oxygen species (ROS) is an initiating cause in the pathogenesis of diabetic complications. However, uncoupling protein 2 (UCP2) can protect retinal vascular endothelial cells from damage by inhibiting the overproduction of mitochondrial ROS, although the protective mechanism involved is not completely clear. This study aimed to assess the effect and mechanism of UCP2 on the apoptosis of human umbilical vein endothelial cells (HUVECs). HUVECs were cultured in normal glucose (NG, 5.5 mmol/l) or high glucose (HG, 30 mmol/l) medium in the presence or absence of UCP2+/+ lentiviral transfection. Lentivirus-mediated UCP2 overexpression inhibited the apoptosis of HUVECs induced by HG. Treatment with HG resulted in the upregulation of caspase-3 and cytochrome c and the downregulation of Bcl-2 in vitro. Furthermore, compared with the NG group, the rate of apoptosis was significantly increased in the HG group. On day two post-infection, NG cells showed significantly greater HUVEC cell proliferation than HG cells. Notably, UCP2 overexpression inhibited these processes. Taken together, these results suggest that UCP2 promotes cell proliferation and inhibits HG-induced apoptosis in HUVECs via the Bcl-2 up‑ and downregulation of caspase-3 and cytochrome c in vitro. This may provide experimental evidence for the application of UCP2 as a new protective factor for diabetic complications, such as diabetic retinopathy.
    No preview · Article · Feb 2014 · International Journal of Molecular Medicine
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    ABSTRACT: Fluidic patterning is a convenient and versatile tool for the patterning of materials, cells and microstructures on surface and in microchannels. However, its performance is usually limited by transverse diffusion between fluid streams. It would blur the boundary and deteriorate the precision of patterns. In this paper, we adopted geometric confinement to generate biphasic parallel flow that is constituted of oil and water. Since there is minimum transverse diffusion in biphasic parallel flow, the performance of fluid patterning is expected to be improved. The results show that the metal (Silver and Chromium) patterns have distinct boundary and well-controlled geometry in comparison with that by conventional laminar flow patterning. Furthermore, the high biocompatibility of oil phase (perfluorodecalin, PFD) enables the precise patterning of viable bacteria inside microchannels. Our work demonstrated a new route of using biphasic parallel flow to patterning, which would serve wide applications in prototyping and research settings.
    Full-text · Article · Dec 2013 · Biomedical Microdevices
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    ABSTRACT: A minimally invasive and repeatable approach for real-time epidermal growth factor receptor (EGFR) mutation surveillance would be highly beneficial for individualized therapy of late stage lung cancer patients whose surgical specimens are often not available. We aim to develop a viable method to detect EGFR mutations in single circulating tumor cells (CTCs). Using a model CTC system of spiked tumor cells in whole blood, we evaluated EGFR mutation determination in single tumor cells enriched from blood. We used magnetic beads labeled with antibody against leukocyte surface antigens to deplete leukocytes and enrich native CTCs independent of epithelial marker expression level. We then used laser cell microdissection (LCM) to isolate individual CTCs, followed by whole-genome amplification of the DNA for exon 19 microdeletion, L858R and T790M mutation detection by PCR sequencing. EGFR mutations were successfully measured in individual spiked tumor cells enriched from 7.5 ml whole blood. Whole-genome amplification provided sufficient DNA for mutation determination at multiple sites. Ninety-five percent of the single CTCs microdissected by LCM (19/20) yielded PCR amplicons for at least one of the three mutation sites. The amplification success rates were 55 % (11/20) for exon 19 deletion, 45 % (9/20) for T790M, and 85 % (17/20) for L858R. Sequencing of the amplicons showed allele dropout in the amplification reactions, but mutations were correctly identified in 80 % of the amplicons. EGFR mutation determination from single captured tumor cells from blood is feasible with the approach described here. However, to overcome allele dropout and to obtain reliable information about the tumor's EGFR status, multiple individual tumor cells should be assayed.
    No preview · Article · Jul 2013 · Analytical and Bioanalytical Chemistry
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    Zhibin Cheng · Xiaodong Sun · Ye Yang · Heng Wang · Zhi Zheng
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    ABSTRACT: Background: Although malaria remains as one of the leading infectious diseases in the world, the decline in malaria transmission in some area makes it possible to consider elimination of the disease. As countries approach elimination, malaria diagnosis needs to change from diagnosing ill patients to actively detecting infections in all carriers including asymptomatic and low-parasite load patients. However, few of the current diagnostic methods have both the throughput and the sensitivity required.Methods: We adopted a sandwich RNA hybridization assay to detect genus Plasmodium 18S rRNA directly from the whole blood of Plasmodium falciparum and Plasmodium vivax patients without RNA isolation. We tested the assay with 202 febrile patients from malaria endemic areas, using 20μl of each blood sample in 96-well plate format with a two-day ELISA-like workflow. Results were compared with diagnosis using microscopy, rapid diagnostic test (RDT) and genus specific real time PCR.Results: Our assay identified all 66 positive samples diagnosed by microscopy, including 49 poorly stored samples that underwent multiple freeze-thaw due to resource limitation. The assay uncovered three false-negative samples by microscopy and four false-negative samples by RDT, and agreed completely with real time PCR diagnosis. There was no negative sample by our assay that would show positive when tested with other methods. The detection limit of our assay for P. falciparum was 0.04 parasite/μl.Conclusions: The assay's simple workflow, high throughput and sensitivity make it suitable of active malaria screening.
    Full-text · Article · Jan 2013 · Journal of clinical microbiology
  • Zhi Zheng · Zhichao Xiao · Zemin Fang · Youmin Pan

    No preview · Article · Dec 2012 · The American Journal of the Medical Sciences
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    ABSTRACT: There are definite gender differences in patients with macular holes. Menopausal women over 50 years are most affected. We aimed to observe the effect of estrogen on collagen gel contraction by cultured human retinal glial cells. It is speculated that estrogen could strengthen the tensile stress of the macula by maintaining the correct morphology and contraction. Estrogen was used to determine its effects on collagen gel contraction, and its function was measured using morphological changes in cells. Human retinal glial cells were cultured in collagen solution. The cells were then exposed to collagen gels and the degree of contraction of the gel was determined. Estrogen at differing concentrations had no effect on the growth of human retinal glial cells. However, after exposed to collagen gel block, less contraction was noted in the estrogen-treated group than in the control group. Estrogen can inhibit collagen gel contraction by glial cells. These results suggest a mechanism for macular hole formation, which is observed in menopausal females.
    No preview · Article · Nov 2012 · Chinese medical journal

Publication Stats

244 Citations
98.90 Total Impact Points

Institutions

  • 2011-2016
    • Shanghai Jiao Tong University
      • Department of Ophthalmology
      Shanghai, Shanghai Shi, China
  • 2014
    • Hangzhou First People's Hospital
      Hang-hsien, Zhejiang Sheng, China
  • 2013-2014
    • Peking Union Medical College Hospital
      Peping, Beijing, China
    • Chinese Academy of Medical Sciences
      Peping, Beijing, China
  • 2005-2014
    • Huazhong University of Science and Technology
      • Department of Cardio Thoracic Surgery
      Wu-han-shih, Hubei, China
  • 2012
    • Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine
      Shanghai, Shanghai Shi, China
  • 2004-2012
    • Tongji Hospital
      Wu-han-shih, Hubei, China