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Zhang H, Pu J, Qi T, Qi M, Yang C, Li S, Huang K, Zheng L, Tong Q. MicroRNA-145 inhibits the growth, invasion, metastasis and angiogenesis of neuroblastoma cells through targeting hypoxia-inducible factor 2 alpha. Oncogene 2012; 33:387-97. [PMID: 23222716 DOI: 10.1038/onc.2012.574] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 10/01/2012] [Accepted: 10/23/2012] [Indexed: 11/10/2022]
Abstract
Recent evidence shows that hypoxia-inducible factor 2 alpha (HIF-2α) may have critical roles in the growth and progression of neuroblastoma (NB) under non-hypoxic conditions. However, the underlying mechanisms and clinical potentials of normoxic HIF-2α expression in NB still remain largely unknown. In this study, HIF-2α immunostaining was identified in 26/42 NB tissues, which was correlated with clinicopathological features. In subtotal 20 NB cases, microRNA-145 (miR-145) was downregulated and inversely correlated with HIF-2α expression. Bioinformatics analysis revealed a putative miR-145 binding site in the 3'-untranslated region (3'-UTR) of HIF-2α messenger RNA (mRNA). Overexpression or knockdown of miR-145 responsively altered both the mRNA and protein levels of HIF-2α and its downstream genes, cyclin D1, matrix metalloproteinase 14 and vascular endothelial growth factor, in normoxically cultured NB cell lines SH-SY5Y and SK-N-SH. In a luciferase reporter system, miR-145 downregulated the luciferase activity of HIF-2α 3'-UTR, and these effects were abolished by a mutation in the putative miR-145-binding site. Overexpression of miR-145 suppressed the growth, invasion, metastasis and angiogenesis of SH-SY5Y and SK-N-SH cells in vitro and in vivo, while restoration of HIF-2α expression rescued the tumor cells from miR-145-mediated defects in these biological features. Furthermore, anti-miR-145 inhibitor rescued the HIF-2α knockdown-mediated repression on the growth, migration, invasion and angiogenesis of NB cells. These data indicate that miR-145 suppresses HIF-2α expression via the binding site in the 3'-UTR under normoxic conditions, thus inhibiting the aggressiveness and angiogenesis of NB.
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He ZY, Tong Q, Wu SG, Li FY, Lin HX, Guan XX. A comparison of quality of life and satisfaction of women with early-stage breast cancer treated with breast conserving therapy vs. mastectomy in southern China. Support Care Cancer 2012; 20:2441-9. [DOI: 10.1007/s00520-011-1364-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 12/26/2011] [Indexed: 10/14/2022]
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Wang C, Tong Q, Hu XZ, Yang LG, Zhong XQ, Yu Y, Wu JJ, Liu WJ, Li X, Hua GH, Zhao HQ, Zhang SJ. Identification of complex vertebral malformation carriers in Holstein cattle in south China. GENETICS AND MOLECULAR RESEARCH 2011; 10:2443-8. [PMID: 22009856 DOI: 10.4238/2011.october.13.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Complex vertebral malformation (CVM) is a recently described monogenic autosomal recessive hereditary defect of Holstein dairy cattle that causes premature birth, aborted fetuses and stillborn calves. Guanine is substituted by thymine (G>T) in the solute carrier family 35 member A3 gene (SLC35A3). A valine is changed to a phenylalanine at position 180 of uridine 5'-diphosphate-N-acetyl-glucosamine transporter protein. CVM is expected to occur in many countries due to the widespread use of sire semen. We developed a created restriction site PCR (CRS-PCR) method to diagnose CVM in dairy cows. This was tested on 217 cows and 125 bulls selected randomly from a Holstein cattle population in south China. Five Holstein cows and five Holstein bulls were identified to be CVM carriers; the percentages of CVM carriers were estimated to be 2.3, 4.0 and 2.9% in the cows, bulls and entire Holstein cattle sample, respectively.
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Wang F, Chan CH, Chen K, Guan X, Lin HK, Tong Q. Deacetylation of FOXO3 by SIRT1 or SIRT2 leads to Skp2-mediated FOXO3 ubiquitination and degradation. Oncogene 2011; 31:1546-57. [PMID: 21841822 DOI: 10.1038/onc.2011.347] [Citation(s) in RCA: 159] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Sirtuin deacetylases and FOXO (Forkhead box, class O) transcription factors have important roles in many biological pathways, including cancer development. SIRT1 and SIRT2 deacetylate FOXO factors to regulate FOXO function. Because acetylation and ubiquitination both modify the ɛ-amino group of lysine residues, we investigated whether FOXO3 deacetylation by SIRT1 or SIRT2 facilitates FOXO3 ubiquitination and subsequent proteasomal degradation. We found that SIRT1 and SIRT2 promote FOXO3 poly-ubiquitination and degradation. Proteasome-inhibitor treatment prevented sirtuin-induced FOXO3 degradation, indicating that this process is proteasome dependent. In addition, we demonstrated that E3 ubiquitin ligase subunit Skp2 binds preferentially to deacetylated FOXO3. Overexpression of Skp2 caused poly-ubiquitination of FOXO3 and degradation, whereas knockdown of Skp2 increased the amount of FOXO3 protein. We also present evidence that SCF-Skp2 ubiquitinates FOXO3 directly in vitro. Furthermore, mutating four known acetylated lysine residues (K242, K259, K290 and K569) of FOXO3 into arginines to mimic deacetylated FOXO3 resulted in enhanced Skp2 binding but with inhibition of FOXO3 ubiquitination; this suggests that some or all of these four lysine residues are likely the sites for ubiquitination. In the livers of mice deficient in SIRT1, we detected increased expression of FOXO3, indicating SIRT1 regulates FOXO3 protein levels in vivo. Furthermore, we found that the elevation of SIRT1 and Skp2 expression in malignant PC3 and DU145 prostate cells is responsible for the downregulation of FOXO3 protein levels in these cells. Taken together, our data support the notion that deacetylation of FOXO3 by SIRT1 or SIRT2 facilitates Skp2-mediated FOXO3 poly-ubiquitination and proteasomal degradation.
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Liang Z, Guo J, Zhang H, Yang C, Pu J, Mei H, Zheng L, Tong Q. Lymphatic sparing versus lymphatic non-sparing laparoscopic varicocelectomy in children and adolescents: a systematic review and meta-analysis. Eur J Pediatr Surg 2011; 21:147-53. [PMID: 21351044 DOI: 10.1055/s-0031-1271733] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE The aim of this study was to explore the true efficacy and potential advantages of lymphatic sparing laparoscopic varicocelectomy (LSV) over lymphatic non-sparing laparoscopic varicocelectomy (LNSV) in children and adolescents. METHODS A search was made for studies published up until 31 August 2010 using the terms "lymphatic sparing varicocelectomy", "laparoscopy", "adolescent" and "children" in the Medline, Embase, Ovid, Web of Science, and Cochrane databases. Randomized controlled trials (RCTs) and observational clinical studies (OCSs) comparing LSV and LNSV were included. A systematic review and meta-analysis was performed using odds ratios (ORs) for dichotomous variables. RESULTS Out of 127 studies, 2 RCTs and 4 OCSs were eligible for inclusion, comprising 489 cases of LSV and 307 cases of LNSV. The hydrocele rates after LSV were significantly lower than after LNSV (OR = 0.19; 95% confidence interval [CI] = 0.10 to 0.36; p < 0.00001). However, no significant difference was observed between LSV and LNSV with regard to recurrence (OR = 0.65; 95% CI = 0.32-1.33; p = 0.24) or catch-up growth (OR = 2.14; 95% CI =0.97-4.72; p = 0.06). CONCLUSION LSV is valuable in reducing the incidence of postoperative hydrocele, with similar recurrence and catch-up growth rates as LNSV. A series of RCTs are warranted to explore the efficacy of LSV in the management of varicocele in children and adolescents.
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Sun F, Chen J, Tong Q, Zeng S. Structure validation of an integrated waterworks model for trihalomethanes simulation by applying regional sensitivity analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2010; 408:1992-2001. [PMID: 20156637 DOI: 10.1016/j.scitotenv.2010.01.037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2009] [Revised: 11/15/2009] [Accepted: 01/25/2010] [Indexed: 05/28/2023]
Abstract
A previously developed integrated waterworks model for trihalomethanes simulation was validated by applying a new framework for comprehensive model structure validation. The proposed framework followed the procedure of regional sensitivity analysis and also involved correlation analysis and frequency distribution analysis. Through such an analysis framework, a deep insight into model structure and parameters could be gained besides the traditional focuses on model validation, i.e. model performance and rationality of model parameters. The integrated waterworks model, to which the framework was applied, was proved to give good predictions of the simulated variables, and the identified values of model parameters coincided well with the reported values in the literature. The model was also found to have a large proportion of sensitive parameters, no distinct correlations among parameters, and thus a balanced structure. Moreover, most of the sensitive parameters could be well identified and the associated uncertainties significantly reduced. A detailed investigation into the sensitivity, identifiability, and uncertainty of model parameters showed that the model conceptualization was in good agreement with accepted scientific principles and anticipated system behaviors. All these results, therefore, supported the validity and trustworthiness of the model. In addition, further opportunities for refining the model were also proposed.
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Sun F, Chen J, Tong Q, Zeng S. Development and identification of an integrated waterworks model for trihalomethanes simulation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2009; 407:2077-2086. [PMID: 19081127 DOI: 10.1016/j.scitotenv.2008.11.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2008] [Revised: 11/02/2008] [Accepted: 11/09/2008] [Indexed: 05/27/2023]
Abstract
To evaluate the impact that new trihalomethanes (THMs) regulations will have on the performance of conventional waterworks in China, we developed an integrated waterworks model to simulate the dynamic behavior of THMs and other associated components, e.g. organic matter, ammonia, and residual chlorine, throughout the conventional water treatment process, which included pre-chlorination, coagulation-flocculation, sedimentation, filtration and post-chlorination. A comprehensive kinetic scheme that takes into account both the physical and biological mechanisms involved in the water treatment processes and the chemical reactions that result from chlorination was proposed for model conceptualization. In addition, the Petersen matrix was designed to present the model and formulate the mass balance equations for the model variables. The model was then identified using the Hornberger-Spear-Young (HSY) algorithm and tested against field data from the Qingzhou Waterworks in Macao, China. Despite gross uncertainty associated with the field data, the model could generally provide good predictions of the simulated variables and meet the management purposes. Furthermore, the identified model parameters agreed well with values that were reported in the literature and could be reasonably interpreted.
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Li WM, Feng YP, Zhao RX, Fan YZ, Affara NA, Wu JJ, Fang J, Tong Q, Wang C, Zhang SJ. Sex ratio bias in early-dead embryos of chickens collected during the first week of incubation. Poult Sci 2008; 87:2231-3. [PMID: 18931172 DOI: 10.3382/ps.2008-00139] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
According to Mendelian heredity laws, the sex ratio of a given chicken population during hatching is expected to be 1:1. In this study, we collected 432 chicken embryos that died during the first week of incubation from 5 different breeds. The sexes of the early-dead embryos were determined by using the previously described molecular sexing technique of double PCR. The female-to-male sex ratio was analyzed for departure from the expected 1:1 sex ratio by chi(2) testing. These results showed that the number of female dead embryos was significantly greater than that of males in the Hubei local breeding stock, Zhusi, and Hy-line Variety Brown (P < 0.05, P < 0.01, P < 0.01 respectively), with observed female-to-male sex ratios of 1.40:1, 2.03:1, and 2.22:1, respectively. Two other Chinese local breeds (the Yellow chicken and the Aijiaohuang chicken) also showed altered sex ratios, although the differences were not significant. Altogether, these results indicated that female chickens were more likely than male chickens to die at the early stages of incubation.
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Sun F, Chen J, Tong Q, Zeng S. Managing the performance risk of conventional waterworks in compliance with the natural organic matter regulation. WATER RESEARCH 2008; 42:229-37. [PMID: 17675135 DOI: 10.1016/j.watres.2007.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2006] [Revised: 06/30/2007] [Accepted: 07/03/2007] [Indexed: 05/16/2023]
Abstract
In order to understand the dual impact of both deteriorating water resources and stringent water quality regulations on the performance of conventional waterworks on a nationwide level, a methodology of a risk-based screening analysis is developed and further applied to evaluate the natural organic matter (NOM) regulation in the new standards for drinking water quality. Due to the large number of drinking water sources and conventional waterworks, as well as the lack of detailed field observations in China, such an analysis is wholly based on a validated conceptual model. The performance risk of conventional waterworks in compliance with the new regulation is estimated within the framework of risk assessment through Monte Carlo simulation to account for the uncertainties associated with model parameters, source water quality and operation conditions across different waterworks. A screening analysis is simultaneously performed using a task-based Hornberger-Spear-Young algorithm to identify the critical operation parameters that determine the performance risk, based on which potential strategies to manage the performance risk are proposed and evaluated. The effects of the model parameter uncertainties on the simulation results are also discussed.
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Weber CHM, Chiche A, Krausch G, Rosenfeldt S, Ballauff M, Harnau L, Göttker-Schnetmann I, Tong Q, Mecking S. Single lamella nanoparticles of polyethylene. NANO LETTERS 2007; 7:2024-9. [PMID: 17564476 DOI: 10.1021/nl070859f] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We present a complete analysis of the structure of polyethylene (PE) nanoparticles synthesized and stabilized in water under very mild conditions (15 degrees C, 40 atm) by a nickel-catalyzed polymerization in aqueous solution. Combining cryogenic transmission electron microscopy (cryo-TEM) with X-ray scattering, we demonstrate that this new synthetic route leads to a stable dispersion of individual PE nanoparticles with a narrow size distribution. Most of the semicrystalline particles have a hexagonal shape (lateral size 25 nm, thickness 9 nm) and exhibit the habit of a truncated lozenge. The combination of cryo-TEM and small-angle X-ray scattering demonstrates that the particles consist of a single crystalline lamella sandwiched between two thin amorphous polymer layers ("nanohamburgers"). Hence, these nanocrystals that comprise only ca. 14 chains present the smallest single crystals of PE ever reported. The very small thickness of the crystalline lamella (6.3 nm) is related to the extreme undercooling (more than 100 degrees C) that is due to the low temperature at which the polymerization takes place. This strong undercooling cannot be achieved by any other method so far. Dispersions of polyethylene nanocrystals may have a high potential for a further understanding of polymer crystallization as well as for materials science as, e.g., for the fabrication of extremely thin crystalline layers.
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Sun F, Chen J, Tong Q, Zeng S. Integrated risk assessment and screening analysis of drinking water safety of a conventional water supply system. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2007; 56:47-56. [PMID: 17898443 DOI: 10.2166/wst.2007.583] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Management of drinking water safety is changing towards an integrated risk assessment and risk management approach that includes all processes in a water supply system from catchment to consumers. However, given the large number of water supply systems in China and the cost of implementing such a risk assessment procedure, there is a necessity to first conduct a strategic screening analysis at a national level. An integrated methodology of risk assessment and screening analysis is thus proposed to evaluate drinking water safety of a conventional water supply system. The violation probability, indicating drinking water safety, is estimated at different locations of a water supply system in terms of permanganate index, ammonia nitrogen, turbidity, residual chlorine and trihalomethanes. Critical parameters with respect to drinking water safety are then identified, based on which an index system is developed to prioritize conventional water supply systems in implementing a detailed risk assessment procedure. The evaluation results are represented as graphic check matrices for the concerned hazards in drinking water, from which the vulnerability of a conventional water supply system is characterized.
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Sankalé JLG, Tong Q, Hadigan CM, Tan G, Grinspoon SK, Kanki PJ, Hotamisligil GS. Regulation of adiponectin in adipocytes upon exposure to HIV-1. HIV Med 2006; 7:268-74. [PMID: 16630040 DOI: 10.1111/j.1468-1293.2006.00372.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVES Adipose dysregulation, dyslipidemia, and insulin resistance are hallmarks of HIV-related lipodystrophy. The precise mechanisms behind these disturbances are unknown. In HIV-infected patients, we previously demonstrated a strong relationship between lipodystrophy and levels of adiponectin, an adipose peptide implicated in regulation of glucose and lipid metabolisms. In this study we investigated the effect of HIV on adipocytes, to determine whether HIV can directly infect adipocytes and/or alter the regulation and secretion of the adipocyte-derived hormone adiponectin. METHODS Human subcutaneous preadipocytes and adipocytes were exposed to HIV-1 under various conditions. Adiponectin was measured in supernatants and cell lysates. RESULTS Although adipocytes expressed CD4, the major HIV receptor, they could not be infected in vitro. However, exposure to HIV dramatically increased the secretion of adiponectin from human adipocytes, in the absence of infection. This was exacerbated with sustained exposure to HIV in a transwell assay. Further, human peripheral mononuclear cells also produced adiponectin, but this was largely dependent upon T-cell activation. CONCLUSIONS We propose that the stimulation of adiponectin production by HIV can perturb adiponectin regulation, leading to substantially decreased levels upon viral suppression by antiretroviral therapy. These data suggest a potential molecular mechanism of adiponectin regulation in HIV-infected patients.
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Abstract
Previous reports have indicated that vesicular glutamate transporters (VGLUTs) are found only in central neurons. We show that neurons in the gut, which also contain glutamate and markers of intrinsic primary afferent neurons, display VGLUT2 immunoreactivity in several species, including humans. Glutamatergic (VGLUT2-immunoreactive) varicosities, which often co-stored choline acetyltransferase and the vesicular acetylcholine transporter, were apposed to a subset of nerve cell bodies in the submucosal and myenteric plexus. Retrograde tracing with FluoroGold demonstrated that VGLUT2 is found in nodose and dorsal root ganglia neurons innervating the stomach. Thus, VGLUT2 is found in intrinsic and extrinsic primary afferent neurons, which suggests that glutamate is as primary afferent neurotransmitter that transfers information from the mucosa to the enteric plexuses and brain.
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Gindler J, Li Z, Berry RJ, Zheng J, Correa A, Sun X, Wong L, Cheng L, Erickson JD, Wang Y, Tong Q. Folic acid supplements during pregnancy and risk of miscarriage. Lancet 2001; 358:796-800. [PMID: 11564486 DOI: 10.1016/s0140-6736(01)05969-4] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND Although taking supplements that contain 400 microg of folic acid before and during early pregnancy reduces a woman's risk for having a baby with a neural-tube defect (NTD), the effects of such supplements on other pregnancy outcomes remain unclear. We examined whether the use of such supplements affects the occurrence of miscarriage. METHODS Participants were women in China who had taken part in a recent folic acid campaign to prevent NTDs and who had registered in this campaign before they became pregnant for the first time. We examined the risk for miscarriage among women who had confirmed pregnancies and who had or had not taken pills containing only 400 microg of folic acid before and during early pregnancy. RESULTS The overall rate of miscarriage was 9.1% (2155/23806). The rates of miscarriage among women who had and had not taken folic acid pills before and during the first trimester were 9.0% and 9.3%, respectively (risk ratio 0.97 [95% CI 0.84-1.12]). The distributions of gestational age at pregnancy diagnosis and at miscarriage were similar for both groups of women. INTERPRETATION In this population-based study of a cohort of women whose use of folic acid supplements while pregnant had been previously documented and who had been pregnant for the first time, we found no evidence that daily consumption of 400 microg of folic acid before and during early pregnancy influenced their risk for miscarriage.
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Aneja VP, Agarwal A, Roelle PA, Phillips SB, Tong Q, Watkins N, Yablonsky R. Measurements and analysis of criteria pollutants in New Delhi, India. ENVIRONMENT INTERNATIONAL 2001; 27:35-42. [PMID: 11488388 DOI: 10.1016/s0160-4120(01)00051-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Ambient concentrations of carbon monoxide (CO), nitrogen oxides (NOx), sulfur dioxide (SO2), and total suspended particulates (TSP) were measured from January 1997 to November 1998 in the center of downtown [the Income Tax Office (ITO) located on B.S.G. Marg] New Delhi, India. The data consist of 24-h averages of SO2, NOx, and TSP as well as 8 and 24-h averages of CO. The measurements were made in an effort to characterize air pollution in the urban environment of New Delhi and assist in the development of an air quality index. The yearly average CO, NOx, SO2, and TSP concentrations for 1997 and 1998 were found to be 4810+/-2287 and 5772+/-2116 microg/m3, 83+/-35 and 64+/-22 microg/m3, 20+/-8 and 23+/-7 microg/m3, and 409+/-110 and 365+/-100 microg/m3, respectively. In general, the maximum CO, SO2, NOx, and TSP values occurred during the winter with minimum values occurring during the summer, which can be attributed to a combination of meteorological conditions and photochemical activity in the region. The ratio of CO/NOx (approximately 50) indicates that mobile sources are the predominant contributors for these two compounds in the urban air pollution problem in New Delhi. The ratio of SO2/NOx (approximately 0.6) indicates that point sources are contributing to SO2 pollution in the city. The averaged background CO concentrations in New Delhi were also calculated (approximately 1939 microg/m3) which exceed those for Eastern USA (approximately 500 microg/m3). Further, all measured concentrations exceeded the US National Ambient Air Quality Standards (NAAQS) except for SO2. TSP was identified as exceeding the standard on the most frequent basis.
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Way JM, Görgün CZ, Tong Q, Uysal KT, Brown KK, Harrington WW, Oliver WR, Willson TM, Kliewer SA, Hotamisligil GS. Adipose tissue resistin expression is severely suppressed in obesity and stimulated by peroxisome proliferator-activated receptor gamma agonists. J Biol Chem 2001; 276:25651-3. [PMID: 11373275 DOI: 10.1074/jbc.c100189200] [Citation(s) in RCA: 270] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Elevated levels of the hormone resistin, which is secreted by fat cells, are proposed to cause insulin resistance and to serve as a link between obesity and type 2 diabetes. In this report we show that resistin expression is significantly decreased in the white adipose tissue of several different models of obesity including the ob/ob, db/db, tub/tub, and KKA(y) mice compared with their lean counterparts. Furthermore, in response to several different classes of antidiabetic peroxisome proliferator-activated receptor gamma agonists, adipose tissue resistin expression is increased in both ob/ob mice and Zucker diabetic fatty rats. These data demonstrate that experimental obesity in rodents is associated with severely defective resistin expression, and decreases in resistin expression are not required for the antidiabetic actions of peroxisome proliferator-activated receptor gamma agonists.
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Tong Q, Zeng F, Zheng L, Zhao J, Lu G. Apoptosis inducing effects of arsenic trioxide on human bladder cancer cell line BIU-87. Chin Med J (Engl) 2001; 114:402-6. [PMID: 11780464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To explore the apoptosis inducing effects of arsenic trioxide (As2O3) on human bladder cancer cells and elucidate possible mechanisms. METHODS After treatment with As2O3, the growth inhibition rates of human bladder cancer cell line BIU-87 were studied by MTT and cell counts methods. DNA synthesis rates were detected by 3H-TdR assay. The morphological changes of cancer cells were observed by light and electronic microscopy and cell apoptosis rates were detected by TdT-mediated dUTP nick end labeling (TUNEL). bcl-2 gene expression of BIU-87 cells was observed by strept avidin-biotin complex (SABC) immunohistochemical method. RESULTS As2O3 could effectively inhibit the growth of BIU-87 (P < 0.05), which were time and concentration dependent. The inhibition rate of 4.0 mumol/L As2O3 for DNA synthesis of cancer cells was 55.64% (P < 0.01). Partial cancer cells presented the characteristic morphological changes of apoptosis which depended on the time of exposure to drug (P < 0.05). bcl-2 expression of BIU-87 cells was decreased significantly (P < 0.05). CONCLUSION As2O3 can significantly induce apoptosis in bladder cancer cells by down-regulating the expression of the bcl-2 gene and inhibiting DNA synthesis. This provides a potentially effective method for prevention and cure of human bladder cancer.
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Xu Y, Wu J, Pei J, Shi Y, Ji Y, Tong Q. Solution structure of BmP02, a new potassium channel blocker from the venom of the Chinese scorpion Buthus martensi Karsch. Biochemistry 2000; 39:13669-75. [PMID: 11076505 DOI: 10.1021/bi000860s] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BmP02 is a 28-amino acid residue peptide purified from the venom of the Chinese scorpion Buthus martensi Karsch, which had been demonstrated to be a weak blocker of apamin-sensitive calcium-activated potassium channels. Two-dimensional NMR spectroscopy techniques were used to determine the solution structure of BmP02. The results show that BmP02 formed a alpha/beta scorpion fold, the typical three-dimensional structure adopted by most short chain scorpion toxins whose structures have been determined. However, in BmP02 this alpha/beta fold was largely distorted. The alpha-helix was shortened to only one turn, and the loop connecting the helix to the first beta-strand exhibited conformational heterogeneity. The instability of BmP02 could be attributed to a proline at position 17, which is usually a glycine. Because the residue at this position makes intense contact with the alpha-helix, it was supposed that the bulky side chain of proline had pushed the helix away from the beta-sheet. This had a significant influence on the structure and function of BmP02. The alpha-helix rotated by about 40 degrees to avoid Pro17 while forming two disulfides with the second beta-strand. The rotation further caused both ends of the helix to be unwound due to covalent restrictions. According to its structure, BmP02 was supposed to interact with its target via the side chains of Lys11 and Lys13.
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Tong Q, Dalgin G, Xu H, Ting CN, Leiden JM, Hotamisligil GS. Function of GATA transcription factors in preadipocyte-adipocyte transition. Science 2000; 290:134-8. [PMID: 11021798 DOI: 10.1126/science.290.5489.134] [Citation(s) in RCA: 375] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Genes that control the early stages of adipogenesis remain largely unknown. Here, we show that murine GATA-2 and GATA-3 are specifically expressed in white adipocyte precursors and that their down-regulation sets the stage for terminal differentiation. Constitutive GATA-2 and GATA-3 expression suppressed adipocyte differentiation and trapped cells at the preadipocyte stage. This effect is mediated, at least in part, through the direct suppression of peroxisome proliferator-activated receptor gamma. GATA-3-deficient embryonic stem cells exhibit an enhanced capacity to differentiate into adipocytes, and defective GATA-2 and GATA-3 expression is associated with obesity. Thus, GATA-2 and GATA-3 regulate adipocyte differentiation through molecular control of the preadipocyte-adipocyte transition.
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Tong Q, Yang S, Gong Y. A new system for expressing heterologous gene in Escherichia coli regulated by oxygen consistence in the environment. CHINESE JOURNAL OF BIOTECHNOLOGY 2000; 15:177-82. [PMID: 10935165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The expression of Vitreosilla hemoglobin gene (vgb) is regulated by oxygen consistence in E. coli. The gene transcription is activated under the condition of limited oxygen. A new system for expressing heterologous gene in E. coli regulated by dissolved oxygen consistence was constructed. It includes a host bacteria GJ100, which contained T7 RNA polymerase gene controlled by vgb promoter, and an expression vector on which the heterologous gene was under the control of a T7 promoter. The results indicated that E. coli thioredoxin A, IgG binding domain of Staphylococcus protein A(ZZ), snake neurotoxin, salmon calcitonin hexa-polymer, human interleukinII (IL2) and human pro-urokinase genes could be expressed efficiently. Expression level was more than 30% of the total cellular protein.
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He Z, Feng S, Tong Q, Hilgemann DW, Philipson KD. Interaction of PIP(2) with the XIP region of the cardiac Na/Ca exchanger. Am J Physiol Cell Physiol 2000; 278:C661-6. [PMID: 10751315 DOI: 10.1152/ajpcell.2000.278.4.c661] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The sarcolemmal Na/Ca exchanger undergoes an inactivation process in which exchange activity decays over several seconds following activation by the application of Na to the intracellular surface of the protein. Inactivation is eliminated by an increase in membrane phosphatidylinositol 4,5-bisphosphate (PIP(2)). Inactivation is also strongly affected by mutations to a basic 20-amino acid segment of the exchanger known as the endogenous XIP region. The hypothesis that PIP(2) directly interacts with the XIP region of the exchanger was tested. First, we investigated the ability of a peptide with the same sequence as the XIP region to bind to immobilized phospholipid vesicles. (125)I-labeled XIP bound avidly to vesicles containing only a low concentration (<3%) of PIP(2). The binding was specific, in that binding was not displaced by other basic peptides. The effects of altering the sequence of XIP peptides also indicated binding specificity. Second, we examined the functional response to PIP(2) of exchangers with mutated XIP regions. Outward Na/Ca exchange currents were measured using the giant excised patch technique. The mutated exchangers either had no inactivation or accelerated inactivation. In both cases, the exchangers no longer responded to PIP(2) or to PIP(2) antibodies. Overall, the data indicate that the affinity of the endogenous XIP region for PIP(2) is an important determinant of the inactivation process.
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Tong Q, Zeng F, Zhu Z, Lu G. Preliminary study of the in vitro growth inhibition of human bladder cancer cell line BIU-87 by arsenic trioxide. Curr Med Sci 2000; 20:112-5. [PMID: 12845720 DOI: 10.1007/bf02887045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/1999] [Indexed: 11/30/2022]
Abstract
To study the effects of arsenic trioxide (As2O3) on the in vitro growth of human bladder cancer cells and the mechanisms. The growth inhibition rates of human bladder cancer cell line BIU-87 by various concentrations of As2O3 were detected by using MTT method. Cell apoptosis was detected by in situ terminally labeled transferase technique and bcl-2 gene expression of BIU-87 cells was observed by SABC immunohistochemical method. The results showed that As2O3 could inhibit the growth of BIU-87 effectively in a dose-dependent manner. After drug's action, the apoptotic bladder cancer cells were obviously increased, which depended on the prolongation of the action time and Bcl-2 expression of BIU-87 cells was decreased significantly. It was suggested that As2O3 could significantly inhibit the growth of bladder human cancer cells. Inducing cell apoptosis by down-regulating the expression of bcl-2 gene might be one of its action mechanisms.
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Tong Q, Zeng L. Study on the correlation of plasma NO, ET-1 and ALT in the patients with chronic hepatitis and cirrhosis. Curr Med Sci 2000; 20:203-4. [PMID: 11215047 DOI: 10.1007/bf02886989] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The levels of plasma nitric oxide (NO), endothelin-1 (ET-1) and ALT in the patients with chronic hepatitis B and active cirrhosis and the correlation among them were observed and analyzed. NO3- was restored by using cadmium column assay and NO2- measured by heavy nitrogen assay. The primitive NO3- and total restored NO2- (NO3-/NO2-) in plasma of the patients with chronic hepatitis and cirrhosis. Plasma ET-1 and ALT levels were determined by using radioimmunological assay and Lai's assay, respectively. Compared with normal control group, the plasma levels of NO2-/NO2- and ET-1 in the patients with chronic active hepatitis and active cirrhosis were significantly increased (P < 0.05-0.01). There was a positive correlation between NO and ALT, and ET-1 and ALT in the patients with chronic active hepatitis and active cirrhosis respectively. It was suggested that elevation of both NO and ET-1 levels were closely related with injury severity of liver function.
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Chen Z, Wu W, Tong Q, Yan X. [Analysis of Parkinson's EEG based on the complexity measure]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 1999; 16:218-21. [PMID: 12552667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
EEG represents the electricy activity of neurons in human brain; it is of course repeatedly used for studying and analyzing the brain activity and the status of brain function. We analyzed the Parkinson's and normal persons' EEG, with the aid of Kc complexity and C1 complexity defined by Kolmogorov and Xujinhua respectively. The results of the analysis on the data from 200 patients and 200 normal persons indicate that the complexity of EEG can be regarded as a feature classifying the Parkinson's EEG and normal persons' EEG.
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