Li Y.,Peking University |
Cang M.,Inner Mongolia University |
Lee A.S.,Stanford University |
Zhang K.,Chinese Institute of Clinical Medicine |
Liu D.,Inner Mongolia University
PLoS ONE | Year: 2011
Animal embryonic stem cells (ESCs) provide powerful tool for studies of early embryonic development, gene targeting, cloning, and regenerative medicine. However, the majority of attempts to establish ESC lines from large animals, especially ungulate mammals have failed. Recently, another type of pluripotent stem cells, known as induced pluripotent stem cells (iPSCs), have been successfully generated from mouse, human, monkey, rat and pig. In this study we show sheep fibroblasts can be reprogrammed to pluripotency by defined factors using a drug-inducible system. Sheep iPSCs derived in this fashion have a normal karyotype, exhibit morphological features similar to those of human ESCs and express AP, Oct4, Sox2, Nanog and the cell surface marker SSEA-4. Pluripotency of these cells was further confirmed by embryoid body (EB) and teratoma formation assays which generated derivatives of all three germ layers. Our results also show that the substitution of knockout serum replacement (KSR) with fetal bovine serum in culture improves the reprogramming efficiency of sheep iPSCs. Generation of sheep iPSCs places sheep on the front lines of large animal preclinical trials and experiments involving modification of animal genomes. © 2011 Li et al.
Zhang J.,Beijing Normal University |
Wang Y.,Beijing Normal University |
Wang J.,Beijing Normal University |
Zhou X.,Beijing Normal University |
And 3 more authors.
Diabetes | Year: 2014
Type 2 diabetes mellitus (T2DM) is associated with a twofold increased risk of dementia and can affect many cognitive abilities, but its underlying cause is still unclear. In this study, we used a combination of a battery of neuropsychological tests and diffusion tensor imaging (DTI) to explore how T2DM affects white matter (WM) integrity and cognition in 38 T2DM patients and 34 age-, sex-, and education-matched normal control subjects. A battery of neuropsychological tests was used to assess a wide range of cognitive functions. Tract-based spatial statistics combined with region of interest-wise (ROI-wise) analysis of mean values of DTI metrics in ROIs was used to compare group differences of DTI metrics on WM skeletons to identify severely disrupted WM tracts in T2DM. We found that T2DM patients showed 1) various cognitive impairments, including executive function, spatial processing, attention, and working memory deficits; 2) widespread WM disruptions, especially in the whole corpus callosum, the left anterior limb of the internal capsule (ALIC.L), and external capsule (EC); and 3) a positive correlation between executive function and WM integrity in the ALIC.L and the left EC. In conclusion, T2DM patients show various cognitive impairments and widespread WM integrity disruptions, which we attribute to demyelination. Moreover, executive dysfunction closely correlates with WM abnormalities. © 2014 by the American Diabetes Association.
Zhong J.,Chinese Institute of Clinical Medicine
Oncogene | Year: 2014
Human protein arginine N-methyltransferase 2 (PRMT2, HRMT1L1) is a protein that belongs to the arginine methyltransferase family, and it has diverse roles in transcriptional regulation through different mechanisms depending on its binding partners. In this study, we provide evidences for the negative effect of PRMT2 on breast cancer cell proliferation in vitro and in vivo. Morever, cyclin D1, one of the key modulators of cell cycle, was found to be downregulated by PRMT2, and PRMT2 was further shown to suppress the estrogen receptor α-binding affinity to the activator protein-1 (AP-1) site in cyclin D1 promoter through indirect binding with AP-1 site, resulting in the inhibition of cyclin D1 promoter activity in MCF-7 cells. Furthermore, a positive correlation between the expression of PRMT2 and cyclin D1 was confirmed in the breast cancer tissues by using tissue microarray assay. In addition, PRMT2 was found to show a high absent percentage in breast caner cell nuclei and the nuclear loss ratio of PRMT2 was demonstrated to positively correlate with cyclin D1 expression and the increasing tumor grade of invasive ductal carcinoma. Those results offer an essential insight into the effect of PRMT2 on breast carcinogenesis, and PRMT2 nuclear loss might be an important biological marker for the diagnosis of breast cancer.
Tao X.Q.,Chinese Institute of Clinical Medicine
Zhonghua nan ke xue = National journal of andrology | Year: 2010
OBJECTIVE: Gonadotropin releasing hormones (GnRH) regulate the expression of annexin 5 in Leydig cells, and annexin 5 is supposed to be a signal molecule in regulating testosterone secretion. This study aimed to investigate the function of annexin 5 in male reproduction by observing its effect on human sperm motility in vitro. METHODS: The encoding sequence of rat annexin 5 was chemically synthesized and inserted into the HIS fusion expression vector pET28a. The expression of the fusion protein HIS-annexin 5 was induced by isopropyl-beta-D-thiogalactoside (IPTG) under the control of the T7 promoter, and the products were purified by affinity chromatography. The anticoagulant activity of annexin 5 was determined by the modified activated partial thromboplastin time (APTT) test. Semen samples from 15 donors were assigned to a control and an annexin 5 group, the latter treated with recombinant annexin 5 at the concentration of 10(-8) mol/L. Sperm motility and the percentage of grade a + b sperm were measured by computer-assisted semen analysis (CASA) after 20 and 60 min exposure, and the sperm ascending experiment was done after 20 min treatment. RESULTS: The product of the synthesized target gene was 947 bp in length, and the inserted sequence corresponded to the published encoding sequence of rat annexin 5. The plasmid pET28a-annexin 5 was transformed into E. coli BL21(DE3) and IPTG induced a fusion protein with a relative molecular weight of about 36,000, a purity of 95% and a high anticoagulant activity. Compared with the control group, sperm motility and the percentage of grade a + b sperm were increased by 40% (P < 0.01) and 21% (P < 0.01), respectively, after 20 min treatment with annexin 5, but neither showed any significant improvement after 60 min. The sperm ascending altitude was remarkably elevated after annexin 5 treatment, with extremely significant difference from the control group (37.84 +/- 6.35 vs. 49.5 +/- 12.27, P < 0.01). CONCLUSION: An annexin 5 recombinant expression vector was successfully constructed. The protein annexin 5 can be efficiently expressed in E. coli and effectively improve human sperm motility in vitro.
Kang N.,Chinese Institute of Clinical Medicine
Zhonghua nan ke xue = National journal of andrology | Year: 2010
With the popularized use cell phones, more and more concern has been aroused over the effects of their radiation on human health, particularly on male reproduction. Cell phone radiation may cause structural and functional injuries of the testis, alteration of semen parameters, reduction of epididymal sperm concentration and decline of male fertility. This article presents an overview on the impact of cell phone radiation on male reproduction.
Xu Z.,Chinese Institute of Clinical Medicine
Shock | Year: 2016
BACKGROUND:: Galectin-3 is a β-galactoside-binding lectin implicated as a mediator in a variety of inflammatory and fibrotic diseases. However, information about galectin-3 release in patients with acute respiratory distress syndrome (ARDS) is very limited. We sought to determine whether plasma galectin-3 levels were increased in ARDS patients and were associated with disease severity. METHODS:: Patients admitted to intensive care unit (ICU) within 48?h and diagnosed with ARDS were identified. In addition, healthy subjects were assigned to a control group. Plasma samples were collected from patients within 48?h after ICU admission as well as healthy subjects. Plasma galectin-3 levels were measured by ELISA. The primary outcome was mortality at 28 days. RESULTS:: Sixty-three ARDS patients were identified. Among these, 27 patients died within 28 days of admission. The plasma galectin-3 levels of the patients were significantly higher than those of control subjects (median [IQR]: 12.37 [7.94–18.79] versus 5.01 [4.15–5.69] ng/mL, respectively, P?0.0001). Furthermore, galectin-3 levels were significantly higher in non-surviving patients than in those who survived (15.38 [11.59–22.98] vs. 10.07 [7.39–15.54] ng/mL, respectively, P?=?0.0136). Plasma galectin-3 levels were significantly correlated with APACHE II scores and PaO2/FiO2 ratios (Spearmanʼs rho?=?0.44, P?0.0001 and −0.616, P?0.0001, respectively). At an optimal cutoff of 10.59?ng/mL, the sensitivity and specificity of galectin-3 for prediction of 28-day mortality were 81.48% (95% CI 0.62–0.94) and 55.56% (95% CI 0.38–0.72), respectively. CONCLUSIONS:: Higher levels of galectin-3 were significantly associated with disease severity and worse outcomes in ARDS patients. © 2016 by the Shock Society
Zheng F.,Chinese Institute of Clinical Medicine
Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology | Year: 2012
The aim of this study was to explore the effect of mesenchymal stem cell (MSC) conditioned medium (MSC-CM) on proliferation, migration and adhesion of human umbilical vein endothelial cell (CRL1730) and its mechanism. Isolation and purification of MSC were performed with the classic adhering method, the surface markers (CD29, CD90, CD45 and CD34) in MSC were detected by flow cytometry. MSC were treated and cultured for 3 d, the MSC-CM or MSC overexpressing stem cell-derived factor-1 (SDF-1) conditioned medium (Ad-SDF-1-MSC-CM) were collected. Subsequently, CRL1730 cells were treated respectively with 2% FBS-DMEM, 15% FBS-DMEM (control group), MSC-CM or Ad-SDF-1-MSC-CM for 24 h, the proliferation of CRL1730 cells was detected by MTT method. CRL1730 cell migration in vitro was performed by using wound healing system. The adhesion ability of CRL1730 cells was analyzed by microscope. The results indicated that the CRL1730 cells treated with Ad-SDF-1-MSC-CM showed greater proliferative capacity than CRL1730 cells treated with MSC-CM. While adding with AMD3100 5 μmol/L, the blocker of CXCR4, the CRL1730 proliferation mediated by Ad-SDF-1-MSC-CM was significantly reduced. Meanwhile, compared with MSC-CM, Ad-SDF-1-MSC-CM had greater effects for promoting CRL1730 migration and enhancing adhesion ability of CRL1730 cells, these effects were significantly inhibited by AMD3100. It is concluded that MSC-CM promotes the migration and adhesion ability of CRL1730 cells through SDF-1 expressed by MSC.
Jing J.,Chinese Institute of Clinical Medicine
Zhonghua nan ke xue = National journal of andrology | Year: 2012
To study the differentially expressed proteins in the process of annexin 5 stimulating testosterone secretion in cultured rat Leydig cells. Primary rat Leydig cells were cultured in vitro and treated with annexin 5 at the concentration of 1 nmol/L for 24 hours, and the cell proteins were extracted to be compared by two-dimensional gel electrophoresis (2-DE). The differentially expressed protein spots were selected to be analyzed by mass spectrometry. We obtained electrophoresis profiles with high resolution and reproducibility, found 50 differentially expressed protein spots, and identified 36 by mass spectrometry, of which 23 were overexpressed and 13 underexpressed in the Leydig cells treated with annexin 5. Differentially expressed protein profiles were established in the process of annexin 5 stimulating testosterone secretion in cultured rat Leydig cells, and identified the key role of these proteins in testosterone secretion. Our findings might be helpful to illuminate the mechanism of annexin 5 regulating testosterone secretion in rat Leydig cells.
Kong X.,Chinese Institute of Clinical Medicine
Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology | Year: 2010
In order to explore the effect of VEGF on mesenchymal stem cell (MSC) proliferation and its possible signal transduction mechanism, MSC culture was performed with the classical bone marrow adhering method; characteristics of passage 3 rat MSC (P3MSC) was identified through multi-differentiation and surface marker assay (CD34, CD45, CD90, CD29); P3MSC were treated with 20 ng/ml VEGF, and the effect of VEGF on the MSC proliferation was measured during 12, 36 and 72 hours by MTT assay. Subsequently, P3MSC were treated with extracellular-signal regulated kinase (ERK1/2) inhibitor PD98059 (50 μmol/L) or p38 mitogen-activated protein kinase (p38MAPK) inhibitor SB203580 (30 μmol/L) for 30 minutes, the culture medium was replaced with new medium including 20 ng/ml VEGF. After 72 hours, the effect of PD98059 or SB203580 on MSC proliferation mediated by VEGF was measured by MTT assay. The result showed that the cultured MSC expressed PDGFR-α, PDGFR-β and NRP1, but did not express VEGF-R (Flk1 and Flt1). The MSC had the multi-differentiation ability and displayed the characteristics of CD90+ (96.7%), CD29+ (94.6%), CD34- (0.79%) and CD45- (0.84%). The MSC proliferation rate increased gradually with prolonging of the functioning time of 20 ng/ml VEGF, and MSC proliferation rate may reach to maximum value after treating with 20 ng/ml VEGF for 72 hours. The effect of VEGF on MSC proliferation was found to be abolished, even was under level of control group after treating with PD98059 or SB203580 for 30 minutes. Furthermore, the inhibitory effect of PD98059 on MSC proliferation was obviously higher than that of SB203580. It is concluded that the VEGF can promote MSC proliferation, and its possible mechanism may relate to ERK1/2 pathway.
Shi Y.C.,Chinese Institute of Clinical Medicine
Zhonghua nan ke xue = National journal of andrology | Year: 2010
OBJECTIVE: The past few years have seen great progress in the studies of the relationship between AZF microdeletions and male infertility. However, some molecular and clinical concerns are not supported by definitive data. The aim of this study was to investigate the prevalence and types of AZF microdeletions in infertile Chinese men, and the indications for genotype-phenotype correlation. METHODS: We retrospectively analyzed Y chromosome AZF microdeletions among 502 patients with nonobstructive azoospermia and 306 with severe oligozoospermia received in our hospital during the past five years. RESULTS: Microdeletions were detected in 7.80% of the patients (63/808), 9.16% in the men with nonobstructive azoospermia (46/502) and 5.56% in those with severe oligozoospermia (17/306). Complete AZFa and AZFb (P5/Proximal P1) deletions were associated with azoospermia, whereas AZFc deletion with variable spermatogenic phenotypes. A mild decline in sperm concentration was found in one male with partial AZFb deletion. The most frequent deletion was the AZFc b2/b4 subtype (60.32%, 38/63), and 39.47% of the cases (15/38) had sperm in the ejaculate. Of the 63 deletions, only one case of the AZFc b2/b4 type had a sperm concentration of over 2 million sperm/ml. CONCLUSION: AZF microdeletions play a significant role in the diagnosis and evaluation of spermatogenic defects. Larger-scale clinical researches on Y chromosome microdeletions may give us a deeper insight into their mechanism and the genotype-phenotype relationship.