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DeSimone JA, Ye Q, Heck GL. Ion pathways in the taste bud and their significance for transduction. CIBA FOUNDATION SYMPOSIUM 2007; 179:218-29; discussion 229-34. [PMID: 7513272 DOI: 10.1002/9780470514511.ch14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Taste buds share a topology with ion-transporting epithelial and evidence now indicates that neural responses in rats to Na+ salts of differing anion are mediated by both transcellular and paracellular ion transport. Na+ exerts its effects mainly on the transcellular pathway. Neural responses to Na+ salts are enhanced by negative voltage clamp and suppressed by positive clamp in a manner indicating modulation of the apical membrane potential of receptor cells. Anion effects are mainly paracellular. Under zero current clamp increasing anion size reduces the neural response at constant Na+ concentration. Below about 50 mM this difference is entirely eliminated under voltage clamp. This suggests that paracellular transepithelial potentials normally create an anion difference. At higher concentrations the relatively high permeability of the paracellular shunt to Cl- permits sufficient electroneutral diffusion of NaCl below the tight junctions to stimulate cells that do not make direct contact with the oral cavity. In general, the sensitivity of a response to perturbations in the apical membrane potential indicates that some phase of Na+ salt taste transduction is accompanied by changes in an apical membrane channel conductance.
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Yao K, Shen X, Yul S, Lu Q, Deng L, Ye Q, Zhang H, Deng Q, Hu Y, Yang Y. Antimicrobial resistance and serotypes of nasopharyngeal strains of Streptococcus pneumoniae in Chinese children with acute respiratory infections. J Int Med Res 2007; 35:253-67. [PMID: 17542413 DOI: 10.1177/147323000703500210] [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: 11/16/2022] Open
Abstract
This prospective, multicentre, nasal carriage study in Chinese children with upper respiratory infection was carried out over the period from 2000 to 2002. Overall, the prevalence of pneumococcal carriage was 24.9%. Antimicrobial susceptibility tests were performed for 887 isolates of Streptococcus pneumoniae of which 33.5% were intermediately susceptible to penicillin and 6.4% were resistant. Multidrug resistance was very common. Pneumococcal strains (n = 625) were serotyped, showing 72.2% were covered by the 23-valent pneumococcal polysaccharide vaccine and 57.6% by the seven-valent pneumococcal conjugate vaccine. Serogroups 19 and 23 were significantly associated with penicillin resistance, which is increasing in China. Erythromycin, tetracycline and sulphamethoxazole/trimethoprim cannot be recommended as first-line treatments for respiratory tract infection as in some other developing countries. These features of serotype distribution are of importance for surveillance in the era of the new conjugate vaccine. In particular, these features will allow for documentation of serotype replacement after the introduction of widespread vaccination.
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Chandarlapaty S, Scaltriti M, Baselga J, Ye Q, Solit D, Norton L, Rosen N. Extracellular cleaved HER2 (p95) confers partial resistance to trastuzumab but not HSP90 inhibitors in models of HER2 amplified breast cancer. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.10515] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
10515 Background: Breast cancers containing an amplified copy of the HER2 receptor tyrosine kinase represent 20–30% of all cases and antibody directed therapy targeting the extracellular domain of HER2 with trastuzumab has proven broadly efficacious. However, resistance to trastuzumab is a common phenomenon. Recent work has identified a cleaved, 95kD version of HER2 that lacks the extracellular epitope in which the trastuzumab binding site is found. Presence of this so called “p95” has been correlated with a worse clinical prognosis. We hypothesized that p95 may enable tumor resistance to trastuzumab. Methods/Results: We established models of p95 expressing breast cancer by transfecting p95 into preexisting models of HER2 amplified breast cancer. We find that cells expressing p95 display increased resistance to the growth inhibitory effects of trastuzumab. The PI3K-AKT pathway that is downregulated by Trastuzumab is less affected in the p95 expressing cells. Furthermore, p95 demonstrates an association with HER3 that is unaffected by trastuzumab treatment. Next, we evaluated the efficacy of therapies targeted against the intracellular domain of HER2 such as the HSP90 inhibitor, 17-AAG. HER2 requires HSP90 for its conformational stability and inhibitors of HSP90 result in growth inhibition of HER2+ breast cancer. We find that p95 displays a similar requirement for HSP90 as inhibitors of HSP90 result in the degradation of p95. Moreover, cells overexpressing p95 are equally susceptible to the antitumor effects of HSP90 inhibitors as those without high levels of p95. Finally, we utilized an empirically derived, in vivo model of trastuzumab resistance that displays high level expression of p95. As with the transfected models, these tumors retain their sensitivity to HSP90 inhibitors as treatment of mice bearing tumors results in both degradation of HER2 and p95 as well as robust tumor growth inhibition. Conclusions: Given the presence of p95 in human breast tumor samples, the data suggest that p95 may play an important role in mediating clinical resistance to trastuzumab. They further suggest that such tumors may retain their sensitivity to targeted therapy against the intracellular portion of HER2 such as with lapatinib or 17-AAG. No significant financial relationships to disclose.
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Chen X, Adrian J, Cushing T, Dimaio H, Liang L, Mayorga V, Miao S, Peterson MG, Powers JP, Spector F, Stein C, Wright M, Xu D, Ye Q, Jaen J. SAR studies on a novel series of human cytomegalovirus primase inhibitors. Bioorg Med Chem Lett 2007; 17:2188-92. [PMID: 17329103 DOI: 10.1016/j.bmcl.2007.01.109] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2006] [Accepted: 01/24/2007] [Indexed: 11/29/2022]
Abstract
A novel series of imidazolylpyrimidines were found to possess inhibitory activity against the human CMV UL70 primase. Extensive SAR studies on an HTS lead led to potent, orally bioavailable compounds with anti-CMV IC(50) values of 150 nM in both viral yield and viral DNA replication assays and with a much reduced cytotoxicity compared to marketed treatments ganciclovir and cidofovir.
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Cui A, Ye Q, Guzman J, Costabel U. Zytokinproduktion von Alveolarmakrophagen bei den idiopathischen interstitiellen Pneumonien. Pneumologie 2007. [DOI: 10.1055/s-2007-973301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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131
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Ye Q, Cui A, Guzman J, Costabel U. Verstärkte Expression von TNF-Rezeptoren durch BAL-Zellen bei kryptogen-organisierender Pneumonie (COP). Pneumologie 2007. [DOI: 10.1055/s-2007-973305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Chandarlapaty S, Ye Q, Huang K, Fadden P, Rosen N, Solit D. 544 POSTER SNX5542, an oral Hsp90 inhibitor, causes Her2 degradation and inhibition of tumor growth in models of Her2 amplified breast cancer. EJC Suppl 2006. [DOI: 10.1016/s1359-6349(06)70549-3] [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] Open
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133
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Sawai A, Greulich H, Ye Q, Sellers W, Rosen N, Solit D. 543 POSTER Inhibition of Hsp90 function downregulates EGFR and sensitizes EGFR-mutant xenografts to paclitaxel. EJC Suppl 2006. [DOI: 10.1016/s1359-6349(06)70548-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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134
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Xu X, Ye Q, Xu N, He X, Luo G, Zhang X, Zhu J, Zhang Y, Nilsson-Ehle P. Effects of Ischemia-Reperfusion Injury on Apolipoprotein M Expression in the Liver. Transplant Proc 2006; 38:2769-73. [PMID: 17112825 DOI: 10.1016/j.transproceed.2006.08.133] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2006] [Indexed: 10/23/2022]
Abstract
The present study investigated the expression pattern of apolipoprotein M (apoM) mRNA in a rat model of hepatic ischemia-reperfusion injury (IRI). Animals were ischemic for 1 hour followed by various reperfusion times. As expected, serum alanine aminotransferase levels were significantly increased under IRI, which indicated the severity of liver injury. Hepatic mRNA levels of HSP70, which is the most common characterized protein within the family of heat-shock proteins (HSP), were significantly increased after 0.5 to 3 hours of IRI. Plasma C-reactive protein, high-density lipoprotein-cholesterol, and lipoprotein (a) levels were significantly increased after 1-hour ischemia followed by 0.5 to 3 hours of reperfusion. Interestingly, similar to HSP70, apoM mRNA levels in the liver were gradually increased after 0.5 to 3 hours of IRI, whereas it returned to a lower level after 6 or 24 hours of IRI, which indicated that hepatic apoM expression was significantly influenced by the acute phase of IRI. However, plasma apoM levels were not increased in parallel, even slightly decreasing after 0.5 or 1 hour of IRI. We concluded that apoM mRNA expression pattern, like HSP70, in the liver showed rapid, significant changes during hepatic local IRI.
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Cushing TD, Adrian J, Chen X, DiMaio H, Doughan B, Flygare J, Liang L, Mayorga V, Miao S, Mellon H, Peterson MG, Powers JP, Spector F, Stein C, Wright M, Xu D, Ye Q, Jaen J. Discovery of a novel series of inhibitors of human cytomegalovirus primase. Bioorg Med Chem Lett 2006; 16:4879-83. [PMID: 16814545 DOI: 10.1016/j.bmcl.2006.06.066] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Revised: 06/16/2006] [Accepted: 06/16/2006] [Indexed: 11/16/2022]
Abstract
Infection by human cytomegalovirus (hCMV) remains a potent threat to susceptible people throughout the world. We have discovered a series of imidazolyl-pyrimidine compounds, which were found to be irreversible inhibitors of the hCMV UL70 primase based on results from radiolabeling and SAR studies. Two promising analogs are described that rival ganciclovir and cidofovir in antiviral potency and possess improved cytotoxicity profiles.
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Ye Q, Chen B, Tong Z, Nakamura S, Sarria R, Costabel U, Guzman J. Thalidomide reduces IL-18, IL-8 and TNF-alpha release from alveolar macrophages in interstitial lung disease. Eur Respir J 2006; 28:824-31. [PMID: 16837501 DOI: 10.1183/09031936.06.00131505] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Thalidomide exhibits diverse actions of anti-inflammation, immunomodulation and anti-angiogenesis. The efficacy of thalidomide treatment in sarcoidosis with lupus pernio is thought to be due to inhibition of tumour necrosis factor (TNF)-alpha. The mechanisms that underlie the properties of thalidomide are still unclear in interstitial lung disease. The current authors investigated the potential inhibitory effects of thalidomide at concentrations of 0.1, 0.01 and 0.001 mM on the production of transforming growth factor-beta, TNF-alpha, interleukin (IL)-1beta, IL-6, IL-8, IL-10, IL-12p70, IL-12p40 and IL-18 by alveolar macrophages from bronchoalveolar lavage in patients with sarcoidosis (n = 8), hypersensitivity pneumonitis (HP; n = 8) and idiopathic pulmonary fibrosis (IPF; n = 12). In sarcoidosis and HP patients, thalidomide induced a dose-dependent, partial suppression of lipopolysacchride (LPS)-stimulated TNF-alpha, IL-12p40 and IL-18 release. At the highest thalidomide concentration (0.1 mM), LPS-stimulated IL-8 production was also suppressed. In IPF patients, although spontaneous production of TNF-alpha, IL-12p40, IL-18 and IL-8 was lower than in sarcoidosis and HP patients, with LPS stimulation the cytokines were significantly elevated and also partially inhibited by thalidomide. In conclusion, thalidomide has the potential to improve the therapeutic regimens for sarcoidosis, hypersensitivity pneumonitis and idiopathic pulmonary fibrosis by reducing tumour necrosis factor-alpha, interleukin-12p40, interleukin-18 and interleukin-8 production.
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Ye Q, Zhao T, Xu C. The role of under-rib convection in mass transport of methanol through the serpentine flow field and its neighboring porous layer in a DMFC. Electrochim Acta 2006. [DOI: 10.1016/j.electacta.2006.02.021] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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138
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Xu C, Zhao T, Ye Q. Effect of anode backing layer on the cell performance of a direct methanol fuel cell. Electrochim Acta 2006. [DOI: 10.1016/j.electacta.2006.02.030] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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139
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Grbovic OM, Basso AD, Sawai A, Ye Q, Friedlander P, Solit D, Rosen N. V600E B-Raf requires the Hsp90 chaperone for stability and is degraded in response to Hsp90 inhibitors. Proc Natl Acad Sci U S A 2006; 103:57-62. [PMID: 16371460 PMCID: PMC1325013 DOI: 10.1073/pnas.0609973103] [Citation(s) in RCA: 226] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2005] [Indexed: 11/18/2022] Open
Abstract
The Raf family includes three members, of which B-Raf is frequently mutated in melanoma and other tumors. We show that Raf-1 and A-Raf require Hsp90 for stability, whereas B-Raf does not. In contrast, mutated, activated B-Raf binds to an Hsp90-cdc37 complex, which is required for its stability and function. Exposure of melanoma cells and tumors to the Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin results in the degradation of mutant B-Raf, inhibition of mitogen-activated protein kinase activation and cell proliferation, induction of apoptosis, and antitumor activity. These data suggest that activated mutated B-Raf proteins are incompetent for folding in the absence of Hsp90, thus suggesting that the chaperone is required for the clonal evolution of melanomas and other tumors that depend on this mutation. Hsp90 inhibition represents a therapeutic strategy for the treatment of melanoma.
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Chong YM, Ma KL, Leung KM, Chan CY, Ye Q, Bello I, Zhang W, Lee ST. Synthesis and Mechanical Properties of Cubic Boron Nitride /Nanodiamond Composite Films. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/cvde.200506422] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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141
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Chen B, Tong Z, Ye Q, Nakamura S, Costabel U, Guzman J. Expression of tumour necrosis factor receptors by bronchoalveolar cells in hypersensitivity pneumonitis. Eur Respir J 2005; 25:1039-43. [PMID: 15929959 DOI: 10.1183/09031936.05.00084704] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Tumour necrosis factor receptors (TNFR) and the Fas receptor (FasR) have been implicated in the pathogenesis of interstitial lung diseases. The current authors examined the expression of TNFR-1, TNFR-2 and FasR by bronchoalveolar cells in hypersensitivity pneumonitis (HP). Cell surface receptor expression on bronchoalveolar lavage cells was analysed by immunocytochemistry in 11 HP patients, 11 idiopathic pulmonary fibrosis (IPF) patients and 10 controls. TNFR-1, TNFR-2 and FasR were expressed on a higher percentage of alveolar macrophages (AM) in HP compared with controls and IPF patients. TNFR-2 and FasR expression on lymphocytes was also higher in HP than in controls and in IPF. TNFR-1, TNFR-2 and FasR expression correlated positively with the percentage of lymphocytes, and negatively with the percentage of AM in HP. Expression of TNFR-1 on AM and TNFR-2 on lymphocytes correlated with the percentage of neutrophils in HP. In conclusion, this study shows evidence of altered expression of tumour necrosis factor superfamily receptors in hypersensitivity pneumonitis.
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142
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Bauer P, Otero Garcia J, Ye Q, Costabel U. Alveolarproteinose – neue Aspekte in Diagnose und Therapie? Pneumologie 2005. [DOI: 10.1055/s-2005-864320] [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]
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143
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Ye Q, Nakamura S, Guzman J, Dalavanga Y, Poulakis N, Costabel U. Verringerte Expression von Hämoxygenase 1 in Alveolarmakrophagen bei Patienten mit idiopathischer Fibrose. Pneumologie 2005. [DOI: 10.1055/s-2005-864544] [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]
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144
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Ye Q, Chen BM, Tong ZH, Nakamura S, Costabel U, Guzman J. Thalidomidinduzierte Hemmung der TNF-α- und IL-18-Produktion von Alveolarmakrophagen bei interstitieller Lungenerkrankung. Pneumologie 2005. [DOI: 10.1055/s-2005-864531] [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]
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145
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Ye Q, Luo G, He X, Zheng W, Zheng L, Dong X, Xu X, Nilsson-Ehle P, Xu N. Prospective study of relationship between cytomegalovirus pneumonia and viral load in renal transplant recipients. Transplant Proc 2004; 36:3036-41. [PMID: 15686689 DOI: 10.1016/j.transproceed.2004.10.050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The present study prospectively examined the relationship between cytomegalovirus interstitial pneumonia (CMV-IP) and viral load among 56 renal transplant recipients. We sought to identify the cutoff of viral load to predict CMV-IP. Blood samples were obtained weekly within the first 2 months and every second week during 2 to 6 months after kidney transplantations. A commercial real-time polymerase chain reaction (PCR)-method was applied to quantify CMV-DNA in plasma or in leukocytes. Among 54 renal transplant recipients who were analyzed for CMV-DNA in the blood (96.4%), 8 experienced CMV-IP (14.3%) and 2 died (3.6%). After kidney transplantation, CMV-DNA loads were near 0 in plasma before the week 4 and before the week 3 in leukocytes among both groups. From week 5 (week 4, in leukocytes), plasma CMV-DNA loads in the CMV-IP group increased, the peak value reached at week 8 in plasma and the week 9 in leukocytes. Whereas, the CMV-DNA loads both in plasma and in leukocytes in the non-CMV-IP group fluctuated at lower levels, those in plasma were significantly different between the 2 groups at the weeks 5, 7, and 9. For CMV-DNA in leukocytes, there were significant differences between 2 groups from week 6 to week 11. The present study demonstrated that dynamic determination of CMV-DNA may predict the occurrence of CMV-IP. Viral loads over 10(4) copies/mL plasma continuing for 3 weeks may serve as a cutoff to predict CMV-IP.
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Yang H, Zhao T, Ye Q. Addition of non-reacting gases to the anode flow field of DMFCs leading to improved performance. Electrochem commun 2004. [DOI: 10.1016/j.elecom.2004.08.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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147
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Solit DB, Egorin M, Valentin G, Delacruz A, Ye Q, Schwartz L, Larson S, Rosen N, Scher HI. Phase 1 pharmacokinetic and pharmacodynamic trial of docetaxel and 17AAG (17-allylamino-17-demethoxygeldanamycin). J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.3032] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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148
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Ye Q, Shieh JH, Morrone G, Moore MAS. Expression of constitutively active Notch4 (Int-3) modulates myeloid proliferation and differentiation and promotes expansion of hematopoietic progenitors. Leukemia 2004; 18:777-87. [PMID: 14961038 DOI: 10.1038/sj.leu.2403291] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The Notch family of transmembrane receptors has been implicated in the regulation of many developmental processes. In this study, we evaluated the role of Notch4 in immature hematopoietic progenitors by inducing, with retroviral transduction, enforced expression of Int-3, the oncogenic and constitutively active form of mouse Notch4. Int-3-transduced human myeloid leukemia (HL-60) cells demonstrated significantly delayed expression of differentiation markers following retinoic acid and 12-0-tetradecanoylphorbol 13-acetate treatment. Furthermore, HL-60 cells expressing Int-3 displayed a slower growth rate than cells infected with void virus, and accumulation in the G0/G1 phases of cell cycle. Transduction with deletion mutants of Int-3 defined the importance of individual domains of the protein (in particular, the ANK domain and the C-terminal domain) in the inhibition of differentiation and growth arrest of HL-60 cells. When mouse bone marrow enriched for stem cells (5-fluorouracil-resistant, lineage negative) was transduced and cultured for two weeks, the Int-3-transduced population displayed a lower expression of differentiation markers and a three- to five-fold higher frequency of colony-forming cells (CFU-GM/BFU-E) than control cultures. These results strongly support the notion that Notch signaling inhibits differentiation and promotes expansion of hematopoietic stem/progenitor cells.
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Chen Q, Sun S, Ye Q, McCuine S, Huff E, Zhang HB. Construction of two BAC libraries from the wild Mexican diploid potato, Solanum pinnatisectum, and the identification of clones near the late blight and Colorado potato beetle resistance loci. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2004; 108:1002-1009. [PMID: 15067385 DOI: 10.1007/s00122-003-1513-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2003] [Accepted: 09/25/2003] [Indexed: 05/24/2023]
Abstract
To facilitate isolation and characterization of disease and insect resistance genes important to potato, two bacterial artificial chromosome (BAC) libraries were constructed from genomic DNA of the Mexican wild diploid species, Solanum pinnatisectum, which carries high levels of resistance to the most important potato pathogen and pest, the late blight and the Colorado potato beetle (CPB). One of the libraries was constructed from the DNA, partially digested with BamHI, and it consists of 40328 clones with an average insert size of 125 kb. The other library was constructed from the DNA partially digested with EcoRI, and it consists of 17280 clones with an average insert size of 135 kb. The two libraries, together, represent approximately six equivalents of the wild potato haploid genome. Both libraries were evaluated for contamination with organellar DNA sequences and were shown to have a very low percentage (0.65-0.91%) of clones derived from the chloroplast genome. High-density filters, prepared from the two libraries, were screened with ten restriction fragment length polymorphism (RFLP) markers linked to the resistance genes for late blight, CPB, Verticillium wilt and potato cyst nematodes, and the gene Sr1 for the self-incompatibility S-locus. Thirty nine positive clones were identified and at least two positive BAC clones were detected for each RFLP marker. Four markers that are linked to the late blight resistance gene Rpi1 hybridized to 14 BAC clones. Fifteen BAC clones were shown to harbor the PPO (polyphenol oxidase) locus for the CPB resistance by three RFLP probes. Two RFLP markers detected five BAC clones that were linked to the Sr1 gene for self-incompatibility. These results agree with the library's predicted extent of coverage of the potato genome, and indicated that the libraries are useful resources for the molecular isolation of disease and insect resistance genes, as well as other economically important genes in the wild potato species. The development of the two potato BAC libraries provides a starting point, and landmarks for BAC contig construction and chromosome walking towards the map-based cloning of agronomically important target genes in the species.
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Fujita M, Ye Q, Ouchi H, Nakashima N, Hamada N, Hagimoto N, Kuwano K, Mason RJ, Nakanishi Y. Retinoic acid fails to reverse emphysema in adult mouse models. Thorax 2004; 59:224-30. [PMID: 14985558 PMCID: PMC1746974 DOI: 10.1136/thx.2003.010785] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Previous work has shown that all-trans-retinoic acid reverses elastase induced emphysema in rats. Since there is currently no effective treatment for pulmonary emphysema, the effect of retinoic acid should be further investigated in other adult species. A study was undertaken using two murine models of emphysema to evaluate the effect of retinoic acid. METHODS The models used were an elastase induced emphysema model for acute alveolar destruction and a tumour necrosis factor (TNF)-alpha transgenic mouse which exhibits chronic air space enlargement, loss of elastic recoil, increased lung volume, and pulmonary hypertension comparable to human pulmonary emphysema. All-trans-retinoic acid (2 mg/kg) was injected for 12 successive days after the establishment of emphysema. The effects of treatment were evaluated using physiological and morphometric analyses. RESULTS In contrast to the rat, administration of all-trans-retinoic acid in these murine models did not improve the emphysema. Moreover, worsening of emphysema was observed in TNF-alpha transgenic mice treated with all-trans-retinoic acid. The level of keratinocyte chemoattractant (KC), a CXC chemokine, in bronchoalveolar lavage fluid was increased in TNF-alpha transgenic mice following retinoic acid treatment. These data raise the possibility that retinoic acid causes deterioration of emphysema by promoting inflammation in this model. CONCLUSIONS In these models, retinoic acid did not show positive effects on emphysema. The effect of retinoic acid in the treatment of pulmonary emphysema remains controversial, and further studies are required to determine its physiological effects under a variety of experimental conditions.
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