Tao Li

Sun Yat-Sen University of Medical Sciences, Shengcheng, Guangdong, China

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Publications (38)93.72 Total impact

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    ABSTRACT: Context: Polycystic ovary syndrome (PCOS) is the most common cause of dysfunctional ovulation-affecting female fertility. A disintegrin and metalloproteinase with thrombospondin-like motifs (ADAMTS-1) is required for normal ovulation and subsequent fertilization, and the expression of ADAMTS-1 may be altered in PCOS granulosa cells (GCs)-reflecting abnormalities in ovulatory signaling. Objective: The purpose of this paper is to analyze the differential expression of ADAMTS-1 in PCOS patients associated with impaired oocyte quality. Design and Setting: A prospective comparative experimental study was performed at a clinical reproductive medicine center. Patients: Women with PCOS (n=40) and normovulatory controls (n =40) undergoing controlled ovarian hyperstimulation (COH) and in vitro fertilization ( IVF) were recruited in our study. Main Outcome Measures: Differential expression of ADAMTS-1 in GCs was analyzed with immunocytochemistry in PCOS patients and normal controls, and ADAMTS-1 mRNA expression was quantified by RT-PCR. Furthermore, the correlation between ADAMTS-1 mRNA and oocyte quality was analyzed. Results: The expression of ADAMTS-1 was decreased in PCOS patients compared with normally-ovulating women, and was closely related to lower oocyte recovery, oocyte maturity, and fertilization rate. Conclusion: Our study provides evidence that the dysregulated expression of ADAMTS-1 in PCOS may influence oocyte quality-via GCs-oocyte paracrine and endocrine mechanism.
    The Journal of Clinical Endocrinology and Metabolism 03/2014; · 6.31 Impact Factor
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    ABSTRACT: Human embryonic stem cell (hESC) lines are traditionally derived through immunosurgery. Their maintenance in culture requires the presence of mouse embryonic fibroblasts (MEFs) as feeder cells, and media supplemented with basic fibroblast growth factor (bFGF) or other growth factors - both of which might introduce animal-derived culture components. The drawbacks associated with immunosurgery, MEF co-culture, and the cost of growth factors necessitate the exploration of a xeno-free method to maintain the self-renewal capacity of hESCs. Here, we describe an isolation method for the human inner cell mass (ICM), which was then cultured in the absence of exogenous growth factors and in the presence of human foreskin fibroblasts (HFFs) as feeder cells. Three hESC lines were obtained from poor-quality embryos by this near-xeno-free protocol. After culturing for more than ten months, the hESCs retained normal morphology, expressed all expected cell surface markers, could differentiate to embryoid bodies upon culture in vitro, and formed teratomas in vivo. Furthermore, secretion of bFGF by HFFs was observed. In conclusion, this is the first study to describe an inexpensive, xeno-free culture system for the isolation and maintenance of hESCs that does not require bFGF supplementation. Mol. Reprod. Dev. © 2014 Wiley Periodicals, Inc.
    Molecular Reproduction and Development 02/2014; · 2.81 Impact Factor
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    ABSTRACT: Abstract Both microdrop and open methods are commonly used for in vitro fertilization (IVF) protocols for embryo culture as well as oocyte insemination. However, few comparative studies evaluating the microdrop or open method of insemination on the fertilization outcome and subsequent embryo development have been performed. A randomized study was conducted to compare microdrop and open fertilization with respect to fertilization rate and embryo development among non-male factor patients undergoing in vitro fertilization and embryo transfer (IVF-ET). The results presented in this study demonstrate that the fertilization failure rate [total fertilization failure rate (TFF) plus low fertilization rate (<25% oocytes fertilized)] in the microdrop insemination group was higher than in the open insemination group (11.9% versus 3.3%, p < 0.001), while the good quality embryo rate and pregnancy rate did not differ significantly between the groups. As a highly complicated process involving many extrinsic and intrinsic factors, further studies are needed to confirm the effects of these insemination methods on the rate of fertilization failure.
    Systems biology in reproductive medicine 02/2014; · 1.85 Impact Factor
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    ABSTRACT: Retinopathy of prematurity (ROP) is the leading cause of blindness in preterm infants. In this study, we investigated the cytokine levels in cord blood of normal preterm neonates and preterm infants developed ROP. Serum levels of 10 cytokines in umbilical cord blood were measured by multiplex protein arrays from 62 healthy preterm neonates and 30 preterm neonate cases who developed ROP at later stage. Results showed that serum levels of cytokines including interleukin 7 (IL-7), monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein 1 alpha (MIP-1α), and macrophage inflammatory protein 1 beta (MIP-1β) were significantly increased in cases who developed ROP than in healthy preterm neonates (3.5-fold, 3.2-fold, 3.4-fold, and 2.1-fold, respectively), whereas levels of these four cytokines did not reveal any significant differences between healthy preterm infants and normal infants. When comparing the expression of cytokines in ROP patients with different clinical parameters, ROP cases whose gestational age at delivery earlier than 29.0 weeks demonstrated increased levels of MCP-1 and MIP-1β than those later than 29.0 weeks (p < 0.05). Also, ROP cases with birth weight less than 1.28 kg revealed significantly higher level of MIP-1β than those who were heavier than 1.28 kg (p < 0.05). These data indicated that levels of IL-7, MCP-1, MIP-1α, and MIP-1β were associated with increased risk of ROP, in which MIP-1β may be further correlated with the severity of ROP.
    Apmis 01/2014; · 2.07 Impact Factor
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    ABSTRACT: To study the effects of in-vitro matured ooplasm and spindle-chromosome complex (SCC) on the development of spindle-transferred oocytes, reciprocal spindle transfer was conducted between in-vivo and in-vitro matured oocytes. The reconstructed oocytes were divided into four groups according to their different ooplasm sources and SCC, artificially activated and cultured to the blastocyst stage. Oocyte survival, activation and embryo development after spindle transfer manipulation were compared between groups. Survival, activation, and cleavage rates of reconstructed oocytes after spindle transfer manipulation did not differ significantly among the four groups. The eight-cell stage embryo formation rates on day 3 and the blastocyst formation rate on day 6 were not significantly different between the in-vitro and in-vivo matured SCC groups when they were transplanted into in-vivo matured ooplasm. The rate of eight-cell stage embryo formation with in-vitro matured ooplasm was significantly lower (P < 0.05) than that of embryos with in-vivo matured ooplasm, and none of the embryos developed to the blastocyst stage. Therefore, SCC matured in vitro effectively supported the in-vitro development of reconstructed oocytes. Ooplasm matured in vitro, however, could not support the development of reconstructed oocytes, and may not be an appropriate source of ooplasm donation for spindle transfer.
    Reproductive biomedicine online 01/2014; · 2.68 Impact Factor
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    ABSTRACT: The isolation of pure inner cell mass (ICM) and trophectoderm (TE) cells from a single human blastocyst is necessary to obtain accurate gene expression patterns of these cells, which will aid in the understanding of the primary steps of embryo differentiation. However, previously developed pure ICM isolation methods are either time-consuming or alter the normal gene expression patterns of these cells. Here, we demonstrate a simple and effective method of ICM samples isolation from human blastocysts. In total, 35 human blastocysts of all stages with expanded and good morphology were incubated in calcium/magnesium-free HEPES medium for 5 min before micromanipulation. With the aid of a laser, a biopsy pipette was inserted directly into the blastocoel for the suction-based removal of ICM samples. The ICM samples were obtained through simple mechanical pulling force or laser assistance, and each isolation process required 3-4 min. The isolated ICM and TE fractions were subjected to single-cell real-time quantitative RT-PCR to evaluate keratin 18 (KRT18) expression. Finally, 33 paired ICM and TE samples were verified using gene expression analysis. KRT18 was readily detectable in all TE cells but absent in 30 ICM counterparts, indicating a pure ICM isolation rate of 90.9% (30/33). The relative KRT18 expression of three TE samples compared with their three contaminated ICM counterparts was 19-fold (P < 0.001), indicating that the contamination was very weak. These results demonstrate that our ICM isolation method is simple and effective.
    In Vitro Cellular & Developmental Biology - Animal 11/2013; · 1.29 Impact Factor
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    ABSTRACT: To explore the effect of growth differential factor-9 (GDF-9) alone on cell proliferation, cell viability, steroidogenesis, and hormone-stimulated gene expression in cultured mouse theca interstitial cells. Basic research. University hospital. Immature 3- to 4-week-old SPF KM mice obtained from the Laboratory Animal Center of Sun Yat-Sen University. Addition of GDF-9 at different dosages to primary culture of mouse theca interstitial cells. Cell number, cell viability, progesterone and testosterone levels, and hormone-stimulated gene mRNA abundance. Growth differential factor-9 mildly increased the number of mouse theca interstitial cells and cell viability in a dose-dependent manner and mildly inhibited the production of progesterone in mouse theca interstitial cells. Administration of GDF-9 at the dosages of 200 ng/mL and 400 ng/mL resulted in a significant decrease in the testosterone level compared with the control group by 60.42% and 68.76%, respectively. Growth differential factor-9 significantly suppressed Lhcgr mRNA by 47.36%, Cyp11a1 mRNA by 62.30%, and Cyp17a1 mRNA by 55.39%, but had only a mild effect on Star gene expression. Growth differential factor-9 can inhibit the production of testosterone in mouse theca interstitial cells and suppress the corresponding gene expression.
    Fertility and sterility 08/2013; · 3.97 Impact Factor
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    ABSTRACT: To explore a simple method of establishing pluripotent human embryonic stem cell (hESC) lines from single blastomeres of low-quality (LQ) embryos. Blastomeres were isolated from normally fertilized, day-3 pre-implantation LQ embryos by dissolving of the zona pellucida and were then plated directly onto inactivated human foreskin fibroblasts. The subsequent culture was identical to that used to derive a hESC line from the inner cell mass of a blastocyst. The established hESC lines were passaged and characterized. Two hESC lines were produced by culturing the blastomeres individually in a hESC culture system (hESC-CS). Both of the hESC lines maintained a normal 46-chromosome XY karyotype, expressed stemness markers, and showed a pluripotent phenotype, including the ability to differentiate into all three germ layers in vitro and in vivo. The blastomeres of LQ embryos have a developmental capacity that necessitates prolonged culture. Plating of blastomeres from LQ embryos directly into the hESC-CS is a feasible method for deriving hESC lines.
    Journal of Assisted Reproduction and Genetics 07/2013; · 1.82 Impact Factor
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    ABSTRACT: Neovascularization is the main characteristic of the proliferative stage of diabetic retinopathy. It has been proven that cell cycle regulation is involved in angiogenesis. The cell cycle regulators, Cip/Kip protein family, belong to the cyclin-dependent kinase inhibitors, are versatile proteins, and except for their function in cell cycle regulation, they also participate in transcription, apoptosis and migration. The expression profiles of the Cip/Kip family in human retina microvascular endothelial cells (HRECs) under normal or high glucose conditions has not been described before. This study was undertaken to determine the expression profiles of the Cip/Kip family proteins, e.g., proteins which are influenced by high glucose and in what manner. Western blot and immunofluorescence analyses were used to investigate the protein expression profiles. Only p21(cip1) and p27(kip1) were detected in HRECs, and they were located in the nucleus. P21(cip1) protein abundance was higher than p27(kip1) in HRECs. Incubation of HRECs in medium containing 30 mM D-glucose for 48 h resulted in downregulation of p21(cip1) protein expression, but had no influence on p27(kip1) protein levels or p21(cip1) mRNA abundance. These results were accompanied by cell cycle G1 phase exit and a lower cell survival rate. Our data show for the first time that high glucose changes the Cip/Kip family expression profiles in HRECs, which may be the foundation for the investigation of the role of the Cip/Kip family in the pathogenesis of diabetic retinopathy.
    Journal of molecular histology 05/2013; · 1.75 Impact Factor
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    ABSTRACT: To completely avoid ice crystal formation and thus get a higher survival rate, vitrification methods have been commonly used for cryopreservation of oocytes and embryos. However,currently used vitrification methods for oocytes and embryos are not suitable for the cryopreservation of preantral follicles (PFs). In the present study, stainless steel mesh was fabricated into mini mesh cups to vitrify isolated PFs. Moreover, isolated follicles were encapsulated and then subjected to vitreous cryopreservation to facilitate in vitro culture/maturation of follicles after warming. The results showed that the percentages of viable follicles did not differ significantly between the vitrification group and fresh group soon after warming (81.25% vs. 85.29%, P>0.05) and after a 7-day culture period (77.78% vs. 83.33%, P>0.05). No difference in mean follicular diameter was observed between cryopreserved and fresh follicles when cultured in vitro. Transmission electron microscopic analysis revealed that vitreous cryopreservation could maintain the ultrastructure of follicles in alginate beads. In conclusion, the present vitrification method could efficiently cryopreserve isolated human ovarian follicles encapsulated by calcium alginate, which could be put into immediate use (in vitro culture/ maturation) after warming. However, more follicles and some detailed biochemical analyses are required to further investigate the effects of vitrification on the long-term growth of human encapsulated PFs.
    Journal of Reproduction and Development 03/2013; · 1.76 Impact Factor
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    ABSTRACT: Shortened exposure of oocytes to spermatozoa has been reported to improve embryo quality. This technique requires extra manipulation of gametes in order to remove oocytes from the spermatozoa. This study presents a fertilization method that does not require additional manipulation and interference of oocytes during fertilization. To determine the benefits of this method, a prospective controlled study using sibling oocytes was conducted. The oocytes of patients were randomly allocated to study and control groups. Fertilization rates, embryo cleavage rates, day-3 embryo morphology and clinical pregnancy rates were compared between the two groups. The normal fertilization rates (2PN) of the two groups were comparable. The percentage of usable embryos (transferred plus cryopreserved embryos) was significantly higher in the treatment group compared with the control group (66.9±23.3% versus 57.6±26.7%; P=0.03). The mean embryo quality score of the treatment group was higher than the control group (18.3±4.8 versus 15.2±5.1; P=0.02). The results of this study demonstrated that this method can improve embryo quality, but further studies with additional IVF patients are needed to confirm the beneficial effects. A new method is presented which decreases the negative effects of an excessive number of spermatozoa on oocytes during the fertilization process without any manipulation and interference of oocytes. The method is easy to perform in a clinical IVF laboratory and led to improved embryo quality in our sibling-oocyte controlled study.
    Reproductive biomedicine online 12/2012; · 2.68 Impact Factor
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    ABSTRACT: BACKGROUND: It has been proved that air quality is crucial for the success of IVF because of the presence of volatile organic compounds (VOCs), microbes, and perfumes, all of which can be harmful to embryo development in vitro. Therefore IVF laboratories are equipped with high efficiency particulate air (HEPA), and activated carbon filters plus positive pressure for air particulate control, with or without CODA system. Here we introduce a new technology using specially treated Honeycomb matrix media aligned in the Landson ™ series system for our laboratory air purification and its impact on IVF outcome. METHODS: Air samples were collected outside and inside the laboratory, and intra-incubator at three different time points, before and after changing carbon filters and after Landson system installation, and we correlated air compounds measure variation with IVF outcome from 1403 cycles. RESULTS: An improvement of air quality was confirmed with passages of total VOCs from 0.42 mg/m(3), 30.48 mg/m(3), 9.62 mg/m3, to 0.1 mg/m(3), 2.5 mg/m(3), 2.19 mg/m(3) through 0.07 mg/m(3), 0.16 mg/m(3), 0.29 mg/m(3), outside the laboratory, inside laboratory and intra-incubator respectively at three separated air sampling times. A clear decrease was observed in some VOCs such as formaldehyde, ethylene, acethylene, propylene, SO2, pentane, NOx, benzene, Hallon-1211, CFC and alcohol. At the same time a significant difference (P < 0.05) was found between the third testing time TT3 after carbon filter change and Landson system installation and the first testing time TT1 before carbon filter change in fertilization rate 83.7 % vs 70.1 %, embryo cleavage rate 97.35 % vs 90.8 %, day 5 blastocyst formation rate 51.1 % vs 41.7 %, and pregnancy/implantation rates 54.6 %, 34.4 % vs 40.6 %, 26.4 %. CONCLUSION: Air purification by the new technology of Landson ™ series significantly improved IVF laboratory air quality, and embryo quality, thus increased pregnancy and implantation rates.
    Journal of Assisted Reproduction and Genetics 12/2012; · 1.82 Impact Factor
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    ABSTRACT: To evaluate the long-term outcomes of vitrectomy for progressive X-linked retinoschisis. Prospective, nonrandomized, consecutive, interventional case series. Twenty-eight eyes of 22 patients who were diagnosed with progressive X-linked retinoschisis were divided into 2 groups: a nonsurgical group (n = 11) and a vitrectomy group (n = 17). The main outcome measures included best-corrected visual acuity, the area of the macular schisis cavity measured by optical coherence tomography, the retinal anatomic status, and complications. The mean follow-up period was 34.7 months (range, 10 to 68 months). The mean best-corrected visual acuity increased from 20/125 at baseline to 20/55 at the final follow-up in the vitrectomy group (P = .001), but decreased from 20/100 at baseline to 20/400 at the final follow-up in the nonsurgical group (P = .000). In the vitrectomy group, the macular schisis cavity resolved in all 17 eyes; the mean area of the macular schisis cavity decreased from 0.85 mm(2) at baseline to 0.23 mm(2) at the final follow-up (P = .000), and the retinas of 16 eyes (94%) were attached after surgery. In the nonsurgical group, retinal schisis progressively extended in 9 eyes (82%); the mean area of the macular schisis cavity increased from 0.82 mm(2) at baseline to 1.21 mm(2) at the final follow-up (P = .000); in 8 eyes (72%), retinal detachment developed, and 2 eyes (18%) experienced vitreous hemorrhage, which terminated the observations. Vitrectomy may be an effective and essential treatment for patients with progressive X-linked retinoschisis to prevent a deterioration of vision before severe complications developed in their eyes.
    American Journal of Ophthalmology 04/2012; 154(2):394-402.e2. · 4.02 Impact Factor
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    ABSTRACT: The association between lipids and diabetic retinopathy (DR) remains unclear. Only a few studies have reported the association between proliferative diabetic retinopathy (PDR) and the serum concentrations of apolipoprotein A1 (apoA1), apolipoprotein B (apoB) and apolipoprotein E (apoE). So we investigated the lipid profile in type 2 diabetic patients of long duration with very mild nonproliferative diabetic retinopathy (NPDR) or PDR. Serum samples were obtained from 25 type 2 diabetic patients with very mild NPDR and 25 type 2 diabetic patients with PDR, and the two groups were matched by diabetes duration and glycosylated hemoglobin (HbA(1c)) levels. The levels of total cholesterol, triglycerides, LDL cholesterol, HDL cholesterol, apoA1, apoB, and apoE were measured by enzymatic colorimetric, surfactant, and immunotubidimetric method. Compared with PDR subjects, very mild NPDR subjects were characterized by increased HDL cholesterol (P = 0.0433) and apoA1 (P = 0.0290) levels, higher HDL cholesterol/LDL cholesterol (P = 0.0377) and apoA1/apoB (P = 0.0061) ratio in serum. There were significant associations between the decreased apoA1 and low apoA1/apoB ratio in serum and PDR. Even after adjustment for age, decreased apoA1 level (P = 0.0304) and low apoA1/apoB ratio (P = 0.0218) in serum were significantly associated with PDR in type 2 diabetic patients of over 15 years' duration. Low apolipoprotein A1/apolipoprotein B ratio in serum was associated with PDR in type 2 diabetic patients of long duration.
    Albrecht von Graæes Archiv für Ophthalmologie 02/2012; 250(7):957-62. · 1.93 Impact Factor
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    ABSTRACT: Vascular endothelial growth factor (VEGF) is the most potent angiogenic mitogen, and has been associated with angiogenesis. Heparanase is an endoglycosidase that specifically cleaves heparan sulfate side chains, which can induce VEGF expression. The aims of the present study were to evaluate the heparanase expression and its relationship with VEGF in the retina of oxygen-induced retinopathy (OIR) mice, and to investigate the effect of the heparanase inhibitor phosphomannopentaose sulfate (PI-88) in the OIR retinas. Seventy-seven newborn C57BL/6 mice were involved in this study. On postnatal day 7 (P7), pups were exposed to a hyperoxia condition (75% oxygen) for 5 days, and on P12, the mice were returned to room air. Control mice were exposed to room air from birth until P17, with normally developing retinal vasculature. PI-88 was administered intraperitoneally to OIR mice at a dose of 35.7 mg/kg/day for 5 consecutive days. The expression level of heparanase and VEGF in the retinas was assayed using immunohistochemistry, Q-RT-PCR, and western blot. The expression levels of heparanase and VEGF were increased in the OIR retinas compared with the control mice. The Q-RT-PCR results showed that the mRNA expression levels of heparanase and VEGF in OIR retina were increased 1.71 fold (p<0.0001) and 4.34 fold (p<0.0001), respectively. The western blot results showed that the protein expression levels of heparanase and VEGF were increased 1.49 fold (p<0.0001) and 1.72 fold (p<0.0001), respectively, in the OIR retinas compared with the normal retinas. The immunohistochemistry analysis revealed that the heparanase and VEGF signals were intense in the retinal vascular endothelia of the OIR mice but faint in those of the normal controls. The increased protein and mRNA expression levels of heparanase and VEGF in the mouse retinas were significantly decreased by PI-88 administration (p<0.0001). Heparanase expression was upregulated and correlated with an increase in VEGF expression in the OIR mouse retinas, and might be involved in the progress of retinopathy of prematurity. Inhibition of heparanase expression by PI-88 could be used as a novel therapeutic method for retinopathy of prematurity.
    Molecular vision 01/2012; 18:1649-57. · 1.99 Impact Factor
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    ABSTRACT: The objectives of this study were to determine whether high-glucose-induced upregulation of heparanase (HPSE) expression and differential heparanase expression in human retinal vascular endothelial cells (HRECs) can alter HREC migration and proliferation. We also aimed to determine whether HREC migration and proliferation correlate with the levels of protein kinase B (Akt) and extracellular-signal-regulated kinase (ERK) phosphorylation and activation. HRECs were treated with either 5 mM glucose (Glu5) or high (30 mM) glucose (Glu30) for 48 h. Untransfected HRECs were grown in human endothelial serum-free medium (HE-SFM) in the presence of 5 mM glucose and supplemented with 30 mM mannitol for 48 h as an osmotic control (mannitol). HRECs were also infected with a heparanase small interfering RNA recombinant lentiviral vector (HPSE-LV) or a control vector (Con-LV) at a multiplicity of infection (MOI) of 60 for three days. Then the con-LV and HPSE-LV-infected cells were treated with 30 mM glucose for 48 h (Con-LV-Glu30 and HSPE-LV-Glu30, respectively). The expression levels of heparanase mRNA and protein and HREC proliferation and migration were examined using quantitative real-time polymerase chain reaction (qRT-PCR), western blot analysis, 3-(4,5-dimethylthiahiazol-2-y1)-2,5-diphenyltetrazolium bromide assay, bromodeoxyuridine histochemical staining, and the Boyden chamber assay. The expression level of paxillin was examined using immunofluorescent staining. Akt and ERK phosphorylation was evaluated using western blot analysis. We successfully transfected the HPSE RNAi lentiviral vector into HRECs and demonstrated that it can suppress the expression of the heparanase gene in these cells. Western blot and qRT-PCR analyses showed that HRECs treated with a high concentration of glucose exhibited increased heparanase protein and mRNA levels, while the levels were decreased in HRECs that had been infected with HPSE-LV before treatment with high glucose (HPSE-LV-Glu30; p<0.05). The observed increase or decrease in the levels of heparanase correlated with increased or decreased HREC migration and proliferation, respectively (p<0.05). HREC proliferation and migration were found to correlate with Akt and ERK phosphorylation levels (p<0.5). Our results indicate that heparanase plays a significant role in mediating retinal vascular endothelial cell proliferation and migration after the HRECs are exposed to high levels of glucose. Signaling inducing heparanase-stimulated HREC proliferation and migration appears to be related to the activation of Akt and ERK via their phosphorylation.
    Molecular vision 01/2012; 18:1684-95. · 1.99 Impact Factor
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    ABSTRACT: To characterize histone acetylation during meiosis in human oocytes matured in vitro or in vivo. Experimental study. University reproductive medical center. Patients undergoing routine intracytoplasmic sperm injection (ICSI) cycles. Immature and mature oocytes were collected from patients undergoing intracytoplasmic sperm injection. Immunohistochemical assessment of the levels of acetylated lysine-9 of histone-3 (H3K9) and lysine-12 of histone-4 (H4K12) combined with spindle and chromosome configurations in in vitro- and in vivo-matured human oocytes. Transcript levels of histone deacetylases (HDACs) 1 and 2 were measured by single-cell quantitative polymerase chain reaction. Acetylation of H3K9 and H4K12 decreased during human oocyte maturation. Residual H3K9 acetylation was found in 37.7% of oocytes matured in vitro, compared with 11.8% in oocytes matured in vivo. Abnormal metaphase spindle was more frequent in oocytes with residual histone acetylation than without (51.6% vs. 25.4%, respectively). Treatment with the HDAC inhibitor trichostatin A increased the incidence of an abnormal metaphase but had no adverse effect on maturation efficiency. Furthermore, expression of HDAC1 transcripts was significantly lower in oocytes matured in vitro versus in vivo. Reduced HDAC1 expression and insufficient histone deacetylation are associated with metaphase defects in human oocytes matured in vitro.
    Fertility and sterility 11/2011; 97(1):178-84.e3. · 3.97 Impact Factor
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    ABSTRACT: To investigate the differential expression of complement C4b and transthyretin in proliferative vitreoretinopathy (PVR). It was a controlled experimental study. Human vitreous samples of 5 patients with PVR were analyzed by using two-dimensional gel electrophoresis and mass spectrometry, and the results were compared with those from normal control vitreous obtained from donor eyes. An in vivo model of PVR was created by intravitreous injection of cultured rabbit retinal pigment epithelial (RPE) cells. The vitreous of PVR models were analyzed by enzyme linked immunosorbent assay (ELISA) to confirm the proteomic results from the PVR patients. Seventy nine various proteins were expressed differently between PVR and normal vitreous, among which nine up-regulated proteins including complement C4b, transthyretin (TTR), and 7 albumins were identified by mass spectrometry. The up-regulation of complement C4b and TTR in PVR patients was also confirmed by ELISA. The concentration of complement C4b and TTR in normal vitreous were (20.18 ± 1.97) mg/L and (88.58 ± 8.84) mg/L respectively, in PVR patients were (38.1 ± 5.79) mg/L and (112.57 ± 6.89) mg/L respectively, difference significantly between these two groups (C4b: t = 11.54, TTR:t = 9.24; P < 0.05). Differences of complement C4b and TTR expression were observed between PVR and normal vitreous. These results have lead to the assumption that there is a connection between elevated concentrations of both complement C4b and TTR and the pathogenesis of PVR and further studies on the functions of these proteins are required.
    [Zhonghua yan ke za zhi] Chinese journal of ophthalmology 08/2011; 47(8):726-31.
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    ABSTRACT: To evaluate the use of multiple displacement amplification (MDA) for preimplantation genetic diagnosis (PGD) of α- and β-double thalassemia. Whole genome of a single cell was directly amplified using MDA and its products were used as templates in fluorescent gap polymerase chain reaction (PCR) analysis of α-thalassemia and in PCR-reverse dot blot analysis, singleplex fluorescent PCR of β-28 and CD17 mutation and HumTH01 for β-thalassemia. 1) MDA from single cell could produce enough DNA templates for the detection of both α and β-thalassemia; 2) The established MDA-PGD protocol for α- and β-double thalassemia was successfully applied in PGD of six embryos, among which, three were transferred, but no pregnancy ensued. The use of MDA as a universal step allows for the simultaneous diagnosis of two or more hereditary defects.
    Journal of Assisted Reproduction and Genetics 06/2011; 28(10):957-64. · 1.82 Impact Factor
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    ABSTRACT: To identify differentially expressed microRNAs (miRNAs) and expression patterns of specific miRNAs during meiosis in human oocytes. To identify differentially expressed miRNAs, GV oocytes and MII oocytes matured at conventional FSH levels (5.5 ng/ml) were analyzed by miRNA microarray. Real-time RT-PCR was used to confirm the changed miRNAs. To validate the dynamic changes of miRNAs from GV to MII stages, oocytes were divided into four groups (#1-4), corresponding to GV oocytes, MI oocytes, MII oocytes matured in conventional FSH level and MII oocytes matured in high FSH level (2,000 ng/ml) respectively. Compared with GV oocytes, MII oocytes exhibited up-regulation of 4 miRNAs (hsa-miR-193a-5p, hsa-miR-297, hsa-miR-625 and hsa-miR-602), and down-regulation of 11 miRNAs (hsa-miR-888*, hsa-miR-212, hsa-miR-662, hsa-miR-299-5p, hsa-miR-339-5p, hsa-miR-20a, hsa-miR-486-5p, hsa-miR-141*, hsa-miR-768-5p, hsa-miR-376a and hsa-miR-15a). RT-PCR analysis of hsa-miR-15a and hsa-miR-20a expression revealed concordant dynamic changes in oocytes from group 1 to group 4. Specific miRNAs in human oocytes had dynamic changes during meiosis. High-concentration FSH in IVM medium led to reverse effect on the expression of hsa-miR-15a and hsa-miR-20a.
    Journal of Assisted Reproduction and Genetics 06/2011; 28(6):559-66. · 1.82 Impact Factor

Publication Stats

290 Citations
93.72 Total Impact Points

Institutions

  • 2004–2014
    • Sun Yat-Sen University of Medical Sciences
      • Reproductive Medical Center
      Shengcheng, Guangdong, China
  • 2007–2013
    • Sun Yat-Sen University
      • State Key Laboratory of Oncology
      Guangzhou, Guangdong Sheng, China
  • 2011–2012
    • Sun Yat-Sen University Cancer Center
      Shengcheng, Guangdong, China