Bio nter

Kuala Selangor, Malaysia
Kuala Selangor, Malaysia
Time filter
Source Type

Guo Y.,Shanghai JiaoTong University | Guo Y.,Renji Hospital | Guo Y.,Bio nter | Xu Q.,Shanghai JiaoTong University | And 40 more authors.
Cell | Year: 2015

Summary CTCF and the associated cohesin complex play a central role in insulator function and higher-order chromatin organization of mammalian genomes. Recent studies identified a correlation between the orientation of CTCF-binding sites (CBSs) and chromatin loops. To test the functional significance of this observation, we combined CRISPR/Cas9-based genomic-DNA-fragment editing with chromosome-conformation-capture experiments to show that the location and relative orientations of CBSs determine the specificity of long-range chromatin looping in mammalian genomes, using protocadherin (Pcdh) and β-globin as model genes. Inversion of CBS elements within the Pcdh enhancer reconfigures the topology of chromatin loops between the distal enhancer and target promoters and alters gene-expression patterns. Thus, although enhancers can function in an orientation-independent manner in reporter assays, in the native chromosome context, the orientation of at least some enhancers carrying CBSs can determine both the architecture of topological chromatin domains and enhancer/promoter specificity. These findings reveal how 3D chromosome architecture can be encoded by linear genome sequences. © 2015 Elsevier Inc.

Xiao Y.,Bio nter | Xiao Y.,CAS Shanghai Institutes for Biological Sciences | Zhang J.,Bio nter | Zhang J.,CAS Shanghai Institutes for Biological Sciences | And 16 more authors.
Psychiatric Genetics | Year: 2011

Objective: Bipolar disorder is a common, severe, and recurrent psychiatric disorder. The Disrupted in Schizophrenia 1 (DISC1) gene has been associated with the risk of schizophrenia, schizoaffective disorder, bipolar disorder, major depression, autism, and Asperger syndrome in different populations. Here, we report the first association study for the DISC1 with bipolar disorder in Chinese cohorts. Methods: We conducted a case-control study and genotyped 12 single nucleotide polymorphisms in 506 bipolar patients and 507 controls recruited from Anhui province in China. The genotyping procedure was carried on the ABI 7900 DNA detection platform by using TaqMan probe technology. RESULT: Although the data did not show association between any individual single nucleotide polymorphism in the DISC1 gene and bipolar disorder, a haplotype [rs2738864 (C)-rs16841582 (C)] was found to be associated with the disorder (P=0.0191). Conclusion: This finding provides evidence supporting the role of DISC1 gene in bipolar disorder, and shows the presence of population heterogeneity. © 2011 Wolters Kluwer Health. Lippincott Williams & Wilkins.

Thiagarajah K.,Bio nter | Wong C.-Y.,Cytopeutics Selangor | Vijayan V.V.,Bio nter | Ooi G.-C.,Bio nter | And 3 more authors.
Transfusion | Year: 2015

Background: Processed umbilical cord blood (UCB) must be stored at cryogenic temperature at all times to maintain the quality and viability of the cells. However, a challenge is presented in the form of moving a large number of cryopreserved UCB samples to a new location. In this report, we share our experience on relocating more than 100,000 units of cryopreserved UCB samples stored in 12 liquid nitrogen freezers (LNFs) to our new laboratory. Study Design and Methods: For quality control purposes, 2 weeks before relocation, donor UCB samples were processed, cryopreserved, and stored in each LNF. On relocation day, half of the samples were retrieved to determine total nucleated cell count, percentage of CD34+ cells, and cell viability as controls for later comparison. UCB samples were transferred into dry shippers before being relocated to the new laboratory. Upon arrival, LNFs were serviced before transferring UCB samples back into its original location within the LNF. The remaining donor UCB samples were retrieved and analyzed for the same tests mentioned. Results: We found no significant differences in pre- and postrelocation values of the tests performed. Conclusion: All UCB samples were successfully relocated into the new laboratory without affecting the quality. © 2014 AABB.

Li Q.,Fudan University | Du J.,Shanghai Institute of Planned Parenthood Research | Feng R.,Fudan University | Xu Y.,Fudan University | And 8 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2014

Context: Telomeres are specialized chromatin structures located at the ends of eukaryotic chromosomes, and telomere length plays a clear role in various diseases. However, it is not known whether telomere length is related to polycystic ovary syndrome (PCOS). Objective: We hypothesized that leukocyte telomere length (LTL) plays an important role in the pathophysiology of PCOS. Design:Weused an established and validated quantitative PCR technique to measure themeanLTL in a large sample of PCOS patients and controls. We used logistic regression and multiple linear regression to analyze the association of PCOS and several related clinical parameters with the age-adjusted ratio of the telomere repeat length to the copy number of a single-copy gene (T/S). Results: Individuals with PCOS (n=698) exhibited significantly shorter LTLs than the controls (n=611) after adjusting for age (0.764 ± 0.016 vs 0.876 ± 0.023; P = .001; odds ratio = 1.403; 95% confidence interval, 1.150-1.712). The mean telomere length in the leukocytes of PCOS patients was comparable tothatofcontrolindividualswhowereonaverage6.16yearsolder. Individualshavingshortertelomere lengths (middle and lowest tertile) had significantly higher disease risk than those having the longest telomere length (highest tertile) (odds ratio=1.614; 95% confidence interval, 1.262-2.066; P=.0001) after adjusting for age. In addition, a significant correlation between the LTL and the level of dehydroepiandrosterone sulfate was observed in controls (r=-0.185; P = .01). Conclusion: We provide the first report that LTL is strongly associated with PCOS. This study suggests a new role for LTL in the pathophysiology of PCOS and might have important implications for our understanding of the etiology of the disease. Copyright © 2014 by the Endocrine Society.

Feng R.,Fudan University | Sang Q.,Fudan University | Zhu Y.,Guangdong No2 Provincial Peoples Hospital | Fu W.,Fudan University | And 11 more authors.
Scientific Reports | Year: 2015

Previous work from our laboratory demonstrated the existence of miRNAs in human follicular fluid. In the current study, we have sought to identify miRNAs that might affect oocyte/embryo quality in patients undergoing intracytoplasmic sperm injection and to investigate their roles in in vitro fertilization outcomes in mouse oocytes. 53 samples were classified as Group 1 (high quality) if the day-3 embryos had seven and more cells or as Group 2 (low quality) if the embryos had six and fewer cells. TaqMan Human microRNAs cards and qRT-PCR were performed to verify differently expressed miRNAs. The function of the corresponding miRNA was investigated in mouse oocytes by injecting them with miRNA-inhibitor oligonucleotides. We found that hsa-miR-320a and hsa-miR-197 had significantly higher expression levels in the Group 1 follicular fluids than in Group 2 (p = 0.0073 and p = 0.008, respectively). Knockdown of mmu-miR-320 in mouse oocytes strongly decreased the proportions of MII oocytes that developed into two-cell and blastocyst stage embryos (p = 0.0048 and p = 0.0069, respectively). Wnt signaling pathway components had abnormal expression level in miR-320 inhibitor-injected oocytes. This study provides the first evidence that miRNAs in human follicular fluid are indicative of and can influence embryo quality.

Feng Y.,Shanghai Medical College | Feng Y.,Institute of Acupuncture Research Collaborating Center for Traditional Medicine | Feng Y.,Fudan University | Feng Y.,Gothenburg University | And 9 more authors.
International Journal of Clinical and Experimental Pathology | Year: 2014

Human ectopic pregnancy (EP) is a leading cause of pregnancy-related death, but the molecular basis underlying the onset of tubal EP is largely unknown. Female Dicer1 conditional knockout mice are infertile with dysfunctional Fallopian tube and have a different miRNA expression profile compared to wild-type mice, and we speculated that Dicer-mediated regulation of miRNA expression and specific miRNA-controlled targets might contribute to the onset of tubal EP. In the present study, we used microarray analysis and quantitative RT-PCR to examine the expression of miRNAs and core miRNA regulatory components in Fallopian tube tissues from women with EP. We found that the levels of DICER1, four miRNAs (let-7i, miR-149, miR-182, and miR-424), and estrogen receptor α distinguished the tubal implantation site from the non-implantation site. Computational algorithms and screening for interactions with the estrogen and progesterone receptor signaling pathways showed that the four miRNAs were predicted to target ten genes, including NEDD4, TAF15, and SPEN. Subsequent experiments showed differences in NEDD4 mRNA and protein levels between the implantation and non-implantation sites. Finally, we revealed that increases in smooth muscle cell NEDD4 and stromal cell TAF15, in parallel with a decrease in epithelial cell SPEN, were associated with tubal implantation. Our study suggests that changes in miRNA levels by the DICER-mediated miRNA-processing machinery result in aberrant expression of cell type-specific proteins that are potentially involved in the onset of tubal EP.

PubMed | Bio nter
Type: Journal Article | Journal: Applied microbiology and biotechnology | Year: 2010

The effect of ammonia on Chinese hamster ovary (CHO) cell growth and galactosylation of recombinant immunoglobulin (rIgG) was investigated using shaking flasks with serum free media containing 0-15 mM NH(4)Cl. The elevated ammonia inhibited cell growth and negatively affected the galactosylation of rIgG. At 15 mM NH(4)Cl, the proportions of monogalactosylated glycan with fucosex (monogalactosylated glycan with fucose) and digalactosylated glycan with fucose (G2F) were 23.9% and 6.3% lower than those at 0 mM NH(4)Cl, respectively. To reduce ammonia formation by cells, glutamate was examined as a substitute for glutamine. The use of glutamate reduced the accumulation of ammonia and enhanced the production of rIgG while depressing cell growth. At 6 mM glutamate, ammonia level did not exceed 2 mM, which is only one third of that at 6 mM glutamine. Also, a 1.7-fold increase in the titer of rIgG and specific rIgG productivity, q (rIgG), was achieved at 6 mM glutamate. The galactosylation of rIgG was favorable at 6 mM glutamate. The proportion of galactosylated glycans, G1F and G2F, at 6 mM glutamate was 59.8%, but it was 50.4% at 6 mM glutamine. The use of glutamate also increased complement-dependent cytotoxicity activity, one of the effector functions of rIgG. Taken together, substitution of glutamine by glutamate can be considered relevant for the production of rIgG in CHO cells since glutamate not only enhances q (rIgG) but also generates a higher galactosylation essential for the effector function of rIgG.

Loading Bio nter collaborators
Loading Bio nter collaborators