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Dummer R, Gutzmer R, Migden M, Dirix L, Lewis K, Combemale P, Higuchi K, Gogov S, Yi T, Herd R, Kudchadkar R, Trefzer U, Lear J, Sellami D, Guminski A. Patient-Reported Quality of Life (Qol) with Sonidegib (Lde225) in Advanced Basal Cell Carcinoma (Bcc). Ann Oncol 2014. [DOI: 10.1093/annonc/mdu344.41] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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77
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Zou L, Yi T, Song X, Li S, Wei Y, Zhao X. Efficient inhibition of intraperitoneal human ovarian cancer growth by short hairpin RNA targeting CD44. Neoplasma 2014; 61:274-82. [PMID: 24824928 DOI: 10.4149/neo_2014_035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
CD44 is one member of a big glycoprotein family involved in adhesion of cells or cells and extracellular matrix (ECM). The heavily glycosylated CD44 has been proved to be a major receptor of hyaluronan and a marker of stem cells in ovarian cancer. Here, using short hairpin (shRNA) against CD44, we demonstrate that knockdown CD44 could inhibit cancer growth efficiently compared with controls. Plasmid targeting CD44 gene (pshCD44) or non-relative control sequences (pshHK) was constructed and delivered to ovarian cancer by biodegradable poly D, L-Lactide-co-glycolide acid nanoparticles (PLGANPs). Nude mice were utilized in an intraperitoneal model of ovarian carcinomatosis to assess antitumor efficacy in vivo. Antitumor efficacy was estimated by changes in tumor weights, proliferation (Ki-67), apoptosis (TUNEL) and angiogenesis (CD31 staining and alginate-encapsulated tumor beads assay) in tumor cells. As results, pshCD44 or pshHK could be effectively transfected into SKOV-3 cells by PLGANPs. Tumor weight in pshCD44/PLGANPs group was suppressed by 45% and 50% compared with those in pshHK/PLGANPs and untreated group, respectively (Ps < 0.001). Inhibition of cell proliferation, induction of apoptosis and reduction of angiogenesis in tumor cells of pshCD44/PLGANPs group also show significant difference compared with those in control groups (Ps < 0.05), respectively. These results indicate that pshCD44 delivered by PLGANPs might be a potential approach in ovarian cancer therapy, and point towards a mechanism involving the inhibition of angiogenesis, cellular proliferation and the induction of apoptosis.
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Yi T, Vick JS, Vecchio MJH, Begin KJ, Bell SP, Delay RJ, Palmer BM. Identifying cellular mechanisms of zinc-induced relaxation in isolated cardiomyocytes. Am J Physiol Heart Circ Physiol 2013; 305:H706-15. [PMID: 23812383 DOI: 10.1152/ajpheart.00025.2013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We tested several molecular and cellular mechanisms of cardiomyocyte contraction-relaxation function that could account for the reduced systolic and enhanced diastolic function observed with exposure to extracellular Zn(2+). Contraction-relaxation function was monitored in isolated rat and mouse cardiomyocytes maintained at 37°C, stimulated at 2 or 6 Hz, and exposed to 32 μM Zn(2+) or vehicle. Intracellular Zn(2+) detected using FluoZin-3 rose to a concentration of ∼13 nM in 3-5 min. Peak sarcomere shortening was significantly reduced and diastolic sarcomere length was elongated after Zn(2+) exposure. Peak intracellular Ca(2+) detected by Fura-2FF was reduced after Zn(2+) exposure. However, the rate of cytosolic Ca(2+) decline reflecting sarcoplasmic reticulum (SR) Ca(2+)-ATPase (SERCA2a) activity and the rate of Na(+)/Ca(2+) exchanger activity evaluated by rapid Na(+)-induced Ca(2+) efflux were unchanged by Zn(2+) exposure. SR Ca(2+) load evaluated by rapid caffeine exposure was reduced by ∼50%, and L-type calcium channel inward current measured by whole cell patch clamp was reduced by ∼70% in cardiomyocytes exposed to Zn(2+). Furthermore, ryanodine receptor (RyR) S2808 and phospholamban (PLB) S16/T17 were markedly dephosphorylated after perfusing hearts with 50 μM Zn(2+). Maximum tension development and thin-filament Ca(2+) sensitivity in chemically skinned cardiac muscle strips were not affected by Zn(2+) exposure. These findings suggest that Zn(2+) suppresses cardiomyocyte systolic function and enhances relaxation function by lowering systolic and diastolic intracellular Ca(2+) concentrations due to a combination of competitive inhibition of Ca(2+) influx through the L-type calcium channel, reduction of SR Ca(2+) load resulting from phospholamban dephosphorylation, and lowered SR Ca(2+) leak via RyR dephosphorylation. The use of the low-Ca(2+)-affinity Fura-2FF likely prevented the detection of changes in diastolic Ca(2+) and SERCA2a function. Other strategies to detect diastolic Ca(2+) in the presence of Zn(2+) are essential for future work.
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Zou L, Song X, Yi T, Li S, Deng H, Chen X, Li Z, Bai Y, Zhong Q, Wei Y, Zhao X. Administration of PLGA nanoparticles carrying shRNA against focal adhesion kinase and CD44 results in enhanced antitumor effects against ovarian cancer. Cancer Gene Ther 2013; 20:242-50. [PMID: 23492823 DOI: 10.1038/cgt.2013.12] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The two membrane-bound proteins, focal adhesion kinase (FAK) and CD44, are involved in processes critical to cancer progression. FAK has an active role in angiogenesis, cell proliferation and cell apoptosis, whereas the heavily glycosylated CD44 has been implicated in cancer metastasis. Here, using short hairpin RNA (shRNA) against FAK and CD44, we demonstrate that simultaneous knockdown of both these genes inhibits cancer growth more efficiently than knockdown of either gene individually. Plasmids targeting these genes or non-relative control sequences were constructed and delivered to ovarian cancer targets by biodegradable poly D,L-lactide-co-glycolide acid nanoparticles (PLGANPs). Nude mice were utilized in an intraperitoneal model of ovarian carcinomatosis to assess antitumor efficacy in vivo. Single gene knockdown resulted in significantly smaller tumors than those observed in the empty-vector control (P's<0.001). More importantly, knockdown of both genes resulted in tumors smaller than both the empty-vector group (P<0.0001) and the single gene knockdown groups (P's<0.001). Knockdown of both FAK and CD44 resulted in tumors with inhibited angiogenesis, reduced proliferation and increased apoptosis as compared with controls (P's<0.001) and single knockdown groups (P's<0.05). These results indicate that dual knockdown of FAK and CD44 in the tumors of patients with ovarian cancer may have an enhanced therapeutic effect, and point toward a mechanism involving the inhibition of angiogenesis, cellular proliferation and the induction of apoptosis.
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80
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Yi T, Cheema Y, Tremble SM, Bell SP, Chen Z, Subramanian M, LeWinter MM, VanBuren P, Palmer BM. Zinc-induced cardiomyocyte relaxation in a rat model of hyperglycemia is independent of myosin isoform. Cardiovasc Diabetol 2012; 11:135. [PMID: 23116444 PMCID: PMC3537566 DOI: 10.1186/1475-2840-11-135] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 10/20/2012] [Indexed: 02/07/2023] Open
Abstract
It has been reported previously that diabetic cardiomyopathy can be inhibited or reverted with chronic zinc supplementation. In the current study, we hypothesized that total cardiac calcium and zinc content is altered in early onset diabetes mellitus characterized in part as hyperglycemia (HG) and that exposure of zinc ion (Zn2+) to isolated cardiomyocytes would enhance contraction-relaxation function in HG more so than in nonHG controls. To better control for differential cardiac myosin isoform expression as occurs in rodents after β-islet cell necrosis, hypothyroidism was induced in 16 rats resulting in 100% β-myosin heavy chain expression in the heart. β-Islet cell necrosis was induced in half of the rats by streptozocin administration. After 6 wks of HG, both HG and nonHG controls rats demonstrated similar myofilament performance measured as thin filament calcium sensitivity, native thin filament velocity in the myosin motility assay and contractile velocity and power. Extracellular Zn2+ reduced cardiomyocyte contractile function in both groups, but enhanced relaxation function significantly in the HG group compared to controls. Most notably, a reduction in diastolic sarcomere length with increasing pacing frequencies, i.e., incomplete relaxation, was more pronounced in the HG compared to controls, but was normalized with extracellular Zn2+ application. This is a novel finding implicating that the detrimental effect of HG on cardiomyocyte Ca2+ regulation can be amelioration by Zn2+. Among the many post-translational modifications examined, only phosphorylation of ryanodine receptor (RyR) at S-2808 was significantly higher in HG compared to nonHG. We did not find in our hypothyroid rats any differentiating effects of HG on myofibrillar protein phosphorylation, lysine acetylation, O-linked N-acetylglucosamine and advanced glycated end-products, which are often implicated as complicating factors in cardiac performance due to HG. Our results suggest that the relaxing effects of Zn2+ on cardiomyocyte function are more pronounced in the HG state due an insulin-dependent effect of enhancing removal of cytosolic Ca2+ via SERCA2a or NCX or by reducing Ca2+ influx via L-type channel or Ca2+ leak through the RyR. Investigations into the effects of Zn2+ on these mechanisms are now underway.
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81
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Borden E, Yi T, Lindner D. P061 SHP-1 inhibitors to enhance signaling and IFN-Γ production by activated T cells, mediate antitumor effects of through IFN-g, and to augment blockade of CTLA-4 by ipilimumab. Cytokine 2012. [DOI: 10.1016/j.cyto.2012.06.146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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82
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Zhou Q, Zhu M, Zhang H, Yi T, Klena JD, Peng Y. Disruption of the p53-p21 pathway inhibits efficiency of the lytic-replication cycle of herpes simplex virus type 2 (HSV-2). Virus Res 2012; 169:91-7. [PMID: 22820403 DOI: 10.1016/j.virusres.2012.07.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 07/11/2012] [Accepted: 07/12/2012] [Indexed: 11/26/2022]
Abstract
Cellular p53 and its downstream mediator p21, the major cellular growth suppression and DNA repair markers, have recently been implicated in viral amplification. Here, we show that herpes simplex virus type 2 (HSV-2) infection of both HCT116 p53(+/+)and NIH3T3 cells resulted in sustained increases of p21. HSV-2 infection did not increase cellular p53 expression, but led to phosphorylation of this protein at Ser20. This phosphorylation was accompanied by the increase of p21 protein levels. Furthermore, specific knockdown of endogenous p21 by siRNAs severely impaired virus production represented by HSV envelope glycoprotein B (gB) expression and progeny virus titers. Disruption of the p53-p21 pathway by either knocking down p53 in HCT116 p53(+/+) and NIH3T3 cells or using p53-deficient HCT116 p53(-/-) cells, led to a significant reduction of HSV-2 production. Together, these results suggest that the p53-p21 pathway is required for efficient HSV-2 lytic replication cycle. Because HSV infection induces the G0/G1 phase arrest at the early step of lytic-replication cycle, we propose that HSV-2 might hijack the cellular p53-p21 pathway to arrest the host cell cycle at G0/G1 phase, blocking cellular DNA synthesis, for its own benefit, i.e., to favor its own viral replication by avoiding competition in generating viral nucleotide pools.
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83
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Ambrose CS, Dubovsky F, Yi T, Belshe RB, Ashkenazi S. The safety and efficacy of live attenuated influenza vaccine in young children with asthma or prior wheezing. Eur J Clin Microbiol Infect Dis 2012; 31:2549-57. [PMID: 22410646 PMCID: PMC3456911 DOI: 10.1007/s10096-012-1595-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 02/16/2012] [Indexed: 11/30/2022]
Abstract
In the European Union and Canada, an Ann Arbor strain live attenuated influenza vaccine (LAIV) is approved for use in children aged 2–17 years, including those with mild to moderate asthma or prior wheezing. The safety and efficacy of LAIV versus trivalent inactivated influenza vaccine (TIV) in children with asthma aged 6–17 years have been demonstrated. However, few data are available for children younger than 6 years of age with asthma or prior wheezing. Safety and efficacy data were collected for children aged 2–5 years with asthma or prior wheezing from two randomized, multinational trials of LAIV and TIV (N = 1,940). Wheezing, lower respiratory illness, and hospitalization were not significantly increased among children receiving LAIV compared with TIV. Increased upper respiratory symptoms and irritability were observed among LAIV recipients (p < 0.05). Relative efficacies were consistent with the results observed in the overall study populations, which demonstrated fewer cases of culture-confirmed influenza illness in LAIV compared with TIV recipients. Study results support the safety and efficacy of LAIV among children aged 2–17 years with mild to moderate asthma or a history of wheezing. Data regarding LAIV use are limited among individuals with severe asthma or active wheezing within the 7 days before vaccination.
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84
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Hefer D, Yi T, Selby DE, Fishbaugher DE, Tremble SM, Begin KJ, Gogo P, Lewinter MM, Meyer M, Palmer BM, Vanburen P. Erythropoietin induces positive inotropic and lusitropic effects in murine and human myocardium. J Mol Cell Cardiol 2011; 52:256-63. [PMID: 22062955 DOI: 10.1016/j.yjmcc.2011.10.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 10/03/2011] [Accepted: 10/07/2011] [Indexed: 11/18/2022]
Abstract
Initial clinical studies indicate a potential beneficial effect of erythropoietin (EPO) in patients with anemia and heart failure. Here, we investigate the direct contractile effects of erythropoietin on myocardial tissue. Treatment with EPO (50U/mL) using excitable murine and human left ventricular muscle preparations resulted in a 37% and 62% increase in twitch tension, respectively (P<0.05). Isolated murine cardiomyocytes exposed to EPO demonstrated a 41% increase in peak sarcomere shortening (P=0.012). Using compounds that specifically stimulate a non-erythropoietic EPO receptor yielded similar increases in contractile dynamics. Cardiomyocyte Ca(2+)dynamics showed an 18% increase in peak calcium in EPO treated cardiomyocytes over controls (P=0.03). Studies in muscle strips skinned after EPO treatment demonstrated a phosphorylation dependant increase in the viscous modulus as well as an increase in oscillatory work. The EPO mediated increase in peak sarcomere shortening was abrogated by PI3-K blockade via wortmannin and by non-isozyme specific PKC blockade by chelerythrine. Finally, EPO treatment resulted in an increase in PKCε in the particulate cellular fraction, indicating activation of this isoform. EPO exhibits direct positive inotropic and lusitropic effects in cardiomyocytes and ventricular muscle preparation. These effects are mediated through PI3-K and PKCε isoform signaling to directly affect both calcium release dynamics and myofilament function.
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85
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Lim JY, Chang YH, Yi T, Kim WC, Song SU, Kim YM. O13. Preservation of salivary gland function following irradiation after transplantation of bone marrow-derived stem cells to irradiated salivary glands in mice. Oral Oncol 2011. [DOI: 10.1016/j.oraloncology.2011.06.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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86
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Yi T, Cheema Y, VanBuren P, Palmer B. Zinc-Enhanced Myofilament Performance is Independent of Direct Effects on Myosin or on Thin Filament Regulatory Proteins. Biophys J 2011. [DOI: 10.1016/j.bpj.2010.12.2686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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87
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Li X, Xiao Y, Liao D, Zheng W, Yi T, Yang Q, Zeng G. Granulation of Simultaneous Partial Nitrification and Anammox Biomass in One Single SBR System. Appl Biochem Biotechnol 2010; 163:1053-65. [DOI: 10.1007/s12010-010-9108-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Accepted: 10/10/2010] [Indexed: 11/30/2022]
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88
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Yi T, Chen Z, Lachapelle R, Palmer BM. Competitive Regulation of Calcium and Zinc Ions in Cardiomyocyte Contraction-Relaxation Function. Biophys J 2010. [DOI: 10.1016/j.bpj.2009.12.1941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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89
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Xiao Y, Liao DX, Li XM, Yang Q, Zeng GM, Yi T, Liu JJ. [Enrichment and dynamic analysis of deammonification granules]. HUAN JING KE XUE= HUANJING KEXUE 2009; 30:2667-2673. [PMID: 19927823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Deammonification process was started-up in a sequencing batch reactor (SBR) seeded with anaerobic granular sludge. A kinetic model describing deammonification process was proposed. Due to the presence of concentration gradient of dissolved oxygen (DO) in granular sludge, model correction factors of DO were introduced. The influences of denitrification process, nitrite and DO on granular sludge activity were studied by model and good agreement was obtained between the experimental results and simulation results. Heterotrophic denitrifiers has some influence on the ANAMMOX process during the initial cultivation, and the influence decreases gradually during the following operation period. When nitrite concentration is 20-30 mg/L, a total nitrogen removal efficiency begins to drop caused by inhibition of nitrite. With high or low DO concentration, the activity of deammonification is inhibited. A total nitrogen removal efficiency can simultaneously reach higher levels by controlling appropriate DO related NH4(+) -N concentration of inflow. In a NH4(+) -N concentration of 80 mg/L, the optimal DO level for a maximal nitrogen gas production is at 0.3-0.6 mg/L.
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90
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Tang LP, Liao DX, Li XM, Zeng GM, Yi T. [Cultivation and nitrogen removal characteristics of deammonifition granules]. HUAN JING KE XUE= HUANJING KEXUE 2009; 30:411-415. [PMID: 19402490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
An SBR reactor seeded with anaerobic granular sludge was started up to enrich deammonifition bacteria and investigate its nitrogen removal characteristics. Research results showed that deammonification granular sludge could be cultivated successfully with firstly enriched ANAMMOX microorganisms in anaerobic condition and then controlled the dissolved oxygen in the SBR reactor between 0.3 and 0.5 mg/L, in which the maximum total nitrogen removal rate reach 75.3%. When the Ca and P concentrations of the medium exceeded the necessary quantity, salt precipitation was observed and interfered with microbial activity and caused a decrease of the nitrogen removal rate of the reactor system. Salt precipitation was avoided by diminishing adequately the Ca and P concentrations of the medium during the following operation period, and the total nitrogen removal rate restored.
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91
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Iclozan C, Liu C, Yu Y, Yi T, Anasetti C, Yu XZ. In VITRO Polarized TH17 Cells Induce Severe Acute Graft-Versus-Host Disease. Biol Blood Marrow Transplant 2009. [DOI: 10.1016/j.bbmt.2008.12.373] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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92
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Yi T, Chen Z, Van Buren PC, Palmer BM. Extracellular Zinc Enhances Cardiomyocyte Relaxation Function in Diabetic Rats. Biophys J 2009. [DOI: 10.1016/j.bpj.2008.12.1281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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93
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Kundu S, Lindner D, Tuthill R, Stark G, Liu L, Gerson S, Borden E, Yi T. 336 POSTER Targeting MKP1 with novel chemical inhibitors sensitizes melanoma and colon cancer cells to chemotherapeutics in vitro and in vivo. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)72270-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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94
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Nelson GN, Roh JD, Mirensky TL, Wang Y, Yi T, Tellides G, Pober JS, Shkarin P, Shapiro EM, Saltzman WM, Papademetris X, Fahmy TM, Breuer CK. Initial evaluation of the use of USPIO cell labeling and noninvasive MR monitoring of human tissue-engineered vascular grafts in vivo. FASEB J 2008; 22:3888-95. [PMID: 18711027 DOI: 10.1096/fj.08-107367] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This pilot study examines noninvasive MR monitoring of tissue-engineered vascular grafts (TEVGs) in vivo using cells labeled with iron oxide nanoparticles. Human aortic smooth muscle cells (hASMCs) were labeled with ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles. The labeled hASMCs, along with human aortic endothelial cells, were incorporated into eight TEVGs and were then surgically implanted as aortic interposition grafts in a C.B-17 SCID/bg mouse host. USPIO-labeled hASMCs persisted in the grafts throughout a 3 wk observation period and allowed noninvasive MR imaging of the human TEVGs for real-time, serial monitoring of hASMC retention. This study demonstrates the feasibility of applying noninvasive imaging techniques for evaluation of in vivo TEVG performance.
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95
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Duan J, Yi T, Lu Z, Shen D, Feng Y. Rice endophytePantoea agglomeransYS19 forms multicellular symplasmata via cell aggregation. FEMS Microbiol Lett 2007; 270:220-6. [PMID: 17391364 DOI: 10.1111/j.1574-6968.2007.00677.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Pantoea agglomerans is characterized by the formation of multicellular symplasmata. One unanswered question regarding this bacterium is how these structures are formed. In this study, the rice diazotrophic endophyte P. agglomerans YS19 was selected for exploration of this theme. YS19 was labeled with green fluorescent protein and the resulting recombinant YS19::gfp was observed to grow only slightly more slowly (a decrease of 5.5%) than the wild-type strain, and to show high GFP label stability (label loss rate 8.9218 x 10(-6) per generation, nearly reaching the generally accepted spontaneous mutation rate for most bacteria). YS19::gfp resembled the wild-type YS19 in symplasmata formation and growth profiles. Based on associated cultivation of both strains by mixing their individually cultivated single cells, symplasmata were formed and composed of both YS19::gfp and YS19, suggesting that YS19 formed symplasmata via aggregation, not proliferation, of the original single cells.
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96
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Yi T, Wei YQ, Tian L, Zhao X, Li J, Deng HX, Wen YJ, Zou CH, Tan GH, Kan B, Su JM, Jiang Y, Mao YQ, Chen P, Wang YS. Humoral and cellular immunity induced by tumor cell vaccine based on the chicken xenogeneic homologous matrix metalloproteinase-2. Cancer Gene Ther 2006; 14:158-64. [PMID: 17124509 DOI: 10.1038/sj.cgt.7700994] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Matrix metalloproteinase-2 (MMP-2) has been used as a target for cancer immunotherapy. The activation of immunization by breaking immune tolerance to self-MMP-2 may be one of the promising approaches for the treatment of MMP-2-positive tumors. In this study, we constructed the xenogeneic tumor cell vaccine c-MMP-2 by transfecting CT26 and LLC cells with chicken MMP-2 cDNA constructs. MMP-2-specific autoantibodies in sera and tumor cells were found in mice immunized with c-MMP-2. Protection against tumor growth was evaluated in respect of the relative contributions of autoantibodies, CD4+, and CD8+ T cells. Treatment with this vaccine (c-MMP-2) also prolonged the survival time of mice bearing cancer. The specific cytotoxic T-cell responses suggested that the treatment increased CD8+ T-cell activity. The antitumor activity of c-MMP-2 was abrogated by in vivo depletion of CD4+ and CD8+ T-lymphocytes and improved by adoptive transfer of CD4+ and CD8+ T-lymphocytes from the mice treated with c-MMP-2. An alternative DNA vaccination strategy for cancer therapy was identified in this study by eliciting humoral and cellular immunoresponse with a crossreacting transfectant.
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97
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Yi T, Fan K, Finke J, Bukowski R, Borden EC. Activation of human peripheral blood immune cells in vitro by sodium stibogluconate (SSG) and SSG/IL-2 combination. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.2557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
2557 Background: SSG, an inhibitor of SHP-1 and SHP2 which are negative regulatory signaling tyrosine phosphatases, suppressed the growth of murine renal carcinoma (Renca) in combination with IL-2 via an interferon (IFN)-γ+ T cell-dependent mechanism (J Immunol 175:7003–8, 2005). Activation of primary human immune cells by SSG or SSG/IL-2 would provide additional supporting evidence for SSG clinical evaluation in combination with IL-2. Methods: Peripheral blood of healthy and melanoma donors were treated in vitro with SSG or SSG/IL-2 and then subjected to ELISPOT assays and FACS analysis for quantification of TH1 (IFN-γ+) and TH2 (IL-5+) cells. Results: Characterization by ELISPOT assays of peripheral blood identified IFN-γ+ cells with marked increase (9.1x) following SSG/IL-2 treatment in contrast to the modest increases induced by SSG alone (2.1x) at its clinically achievable dose (20 μg/ml) or by IL-2 (3.1x) at its Cmax of low-dose schedule (30 IU/ml). SSG at an even higher dose (100 μg/ml) was less effective alone (1.5x) or in combination with IL-2 (7.8x). IL-5+ cells were not induced by the agents individually or in combination. Induction of peripheral IFN-γ+ cells by SSG/IL-2 was detectable after 4 and 16 h. Increased effectiveness of the SSG/IL-2 combination vs. the individual agents in inducing IFN-γ+ cells in vitro was detected by ELISPOT assays in the peripheral blood from 7 healthy donors and 6 melanoma patients. FACS analysis showed that the combination induced IFN-γ+ cells in the CD4+ and CD8+ lymphocytes and also increased lymphocytes expressing the activation marker CD69 in both CD4+ (2–5x) and CD4− populations (∼ 3x). Conclusion: SSG, a compound used clinically for treatment of leishmaniasis, can interact with IL-2 in vitro to activate immune cells in peripheral blood of healthy and melanoma donors. Results provide further rationale, in addition to the mouse tumor data, for proof of concept clinical trials for effecting augmentation of IL-2 through inhibition of negative regulatory signaling phosphatases. No significant financial relationships to disclose.
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Fan K, Pathak M, Zhou M, Lindner D, Borden E, Yi T. 335 SHP-1 protein tyrosine phosphatase as a target molecule in anti-tumor immune therapies: SHP-1 inhibitor SSG interacts withIL-2 to increase anti-murine renal tumor immunity. EJC Suppl 2004. [DOI: 10.1016/s1359-6349(04)80342-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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99
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van Leeuwen JH, Hu Z, Yi T, Pometto ALIII, Jin B. Kinetic Model for Selective Cultivation of Microfungi in a Microscreen Process for Food Processing Wastewater Treatment and Biomass Production. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/abio.200390036] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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100
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Wang Y, Burns W, Tang P, Bai Y, Yi T, Schechner J, Lorber M, Pober J, Tellides G. Gamma-interferon-dependent T cell-mediated injury and remodeling of human coronary arteries. J Heart Lung Transplant 2003. [DOI: 10.1016/s1053-2498(02)00944-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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