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Zhong G, Li H, Shan T, Zhang N. Genetic variability of DNA repair mechanisms in chemotherapy treatment outcome of gastric cancer patients. GENETICS AND MOLECULAR RESEARCH 2015; 14:17228-34. [DOI: 10.4238/2015.december.16.22] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Campbell J, Huang Y, Liu Y, Schenken R, Zhong G. Luciferase imaging of chylamdia muridarum ascending infection in mice. Fertil Steril 2014. [DOI: 10.1016/j.fertnstert.2014.07.959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Hu W, Xie W, Chen S, Zhang N, Zou Y, Dong X, Rashid M, Xiao Y, Hu M, Zhong G. Separation of Cis- and Trans-Cypermethrin by Reversed-Phase High-Performance Liquid Chromatography. J Chromatogr Sci 2014; 53:612-8. [DOI: 10.1093/chromsci/bmu094] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Xie R, Zhang C, van der Veen MH, Arstila K, Hantschel T, Chen B, Zhong G, Robertson J. Carbon nanotube growth for through silicon via application. NANOTECHNOLOGY 2013; 24:125603. [PMID: 23466644 DOI: 10.1088/0957-4484/24/12/125603] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Through silicon via (TSV) technology is key for next generation three-dimensional integrated circuits, and carbon nanotubes (CNT) provide a promising alternative to metal for filling the TSV. Three catalyst preparation methods for achieving CNT growth from the bottom of the TSV are investigated. Compared with sputtering and evaporation, catalyst deposition using dip-coating in a FeCl2 solution is found to be a more efficient method for realizing a bottom-up filling of the TSV (aspect ratio 5 or 10) with CNT. The CNT bundles grown in 5 min exceed the 50 μm length of the TSV and are multi-wall CNT with three to eight walls. The CNT bundles inside the TSV were electrically characterized by creating a direct contact using a four-point nanoprober setup. A low resistance of the CNT bundle of 69.7 Ω (297 Ω) was measured when the CNT bundle was contacted midway along (over the full length of) the 25 μm deep TSV. The electrical characterization in combination with the good filling of the TSV demonstrates the potential use of CNT in fully integrated TSV applications.
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Jin J, Liu J, Chen J, Zhao L, Ma Z, Chen X, Huang M, Zhong G. Bioequivalence evaluation of 2 tablet formulations of entecavir in healthy chinese volunteers: a single-dose, randomized-sequence, open-label crossover study. ARZNEIMITTEL-FORSCHUNG 2012; 62:113-6. [PMID: 22282264 DOI: 10.1055/s-0031-1297964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
A randomized, 2-way crossover study was conducted in healthy Chinese male volunteers to evaluate the bioequivalence of a new generic formulation of entecavir (CAS 142217-69-4) tablets (test) and the available branded formulation (reference) to meet the requirements for marketing the test product in China. Test and reference tablets were administered as a single dose on 2 treatment days separated by a 2-week washout period. Blood samples were collected for a period of 24 h following drug administration. Plasma concentration of entecavir was determined by a liquid chromatography-tandem mass spectrometry (LC/MS/MS) method. Pharmacokinetic parameters were calculated using a noncompartmental model. Bioequivalence was determined by calculating 90% CIs for the ratios of Cmax, AUC0-t and AUC0-∞ values for the test and reference products. Tolerability was assessed by monitoring vital signs, laboratory tests and interviews with the volunteers before administration and every 2 h during the study. The 90% CIs of entecavir for Cmax, AUC0-t and AUC0-∞ were 95.2-106.9%, 98.4-104.6% and 97.3-104.4%, respectively, which fell within the interval of 80-125%. No clinically important adverse effects were reported. These results suggested that the test formulation of entecavir tablets met the regulatory criterion for bioequivalence to the reference formulation.
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Chen P, Song J, Luo LH, Zhong G, Xiao HJ, Gong SS. Abnormal motor reflexes and dormant facial motor neurons in rats with facial-facial anastomosis. J Int Med Res 2009; 37:705-16. [PMID: 19589254 DOI: 10.1177/147323000903700314] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
After facial nerve injury, some post-paralysis sequelae, such as synkinesis, hemispasm and 'crocodile tears' syndrome appear. The psychosocial impact of these sequelae is unavoidable. Despite recent advances and the growing popularity of this field, the pathophysiological mechanisms of facial nerve injury and regeneration are still not well understood. In this report, an abnormal motor reflex coincident with synkinetic facial movement was examined in a rat model using the blink reflex technique. Some dormant facial motor neurons were found which could not innervate through the suture site but remained alive. These results suggest that such dormant neurons might exert roles distinct from those of re-innervated neurons during facial nerve injury and regeneration. Further study is required to elucidate the biomolecular structure and electrophysiological features of such neurons.
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Lu M, Zhu D, Lu Y, Hou Y, Tan B, Zhong G. Organocatalytic asymmetric alpha-aminoxylation/aza-Michael reactions for the synthesis of functionalized tetrahydro-1,2-oxazines. Angew Chem Int Ed Engl 2008; 47:10013. [PMID: 19072787 DOI: 10.1002/anie.200890274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Robertson J, Hofmann S, Cantoro M, Parvez A, Ducati C, Zhong G, Sharma R, Mattevi C. Controlling the catalyst during carbon nanotube growth. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2008; 8:6105-6111. [PMID: 19198352 DOI: 10.1166/jnn.2008.sw08] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We have recently been able to grow single-walled carbon nanotubes by purely thermal chemical vapour deposition (CVD) at temperatures as low as 400 degrees C. This has been achieved by separating the catalyst pre-treatment step from the growth step. In the pre-treatment step, a thin film catalyst is re-arranged into a series of nano-droplets, which are then the active catalysts. Both steps have been studied by in-situ environmental transmission electron microscopy and X-ray photoemission spectroscopy. We have also studied the catalyst yield, the weight of nanotubes grown per weight of transition metal catalyst. Using very thin layers of Fe on Al2O3 support in a remote plasma-assisted CVD, we have achieved yields of order 100,000. This may be due to control of catalyst poisoning by ensuring an etching path.
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Mizukami M, Zhong G, Fukuchi I, Zhang L, Kurihara K. In situpolymerization of molecular macroclusters on silica: poly( N-isopropylacrylamide) nano-films. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308081981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Dong X, Fan Y, Zhong G, Long J, Xiu K, Wang B, Zhang M. Osseointegration of titatinum implant for the transfermoral prosthesis—Animal study. J Biomech 2006. [DOI: 10.1016/s0021-9290(06)84903-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Zhong G, Wang J, Xu M, Xie Z, Yu M, Wang J, Zhou T, Gong W, Sun Y, Hu M, Zhang X, Shen B, Guo N. Enhanced Maturation and Functional Capacity of Dendritic Cells Induced by Mannosylated L2 Domain of ErbB2 Receptor. Scand J Immunol 2005; 62:108-16. [PMID: 16101816 DOI: 10.1111/j.1365-3083.2005.01642.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The nature of antigens and functional state of dendritic cells (DC) are important in antigen presentation. The ability of DC for the induction of T-cell responses is promoted by maturation. It has been confirmed that mannose receptors mediate highly efficient endocytosis and presentation of mannosylated proteins. In the present study, L2 domain of ErbB2 ectodomain was expressed in Escherichia coli, purified and mannosylated. The maturation and functional capacity of DC induced by mannosylated L2 (mL2) protein were investigated. The results showed that L2 protein could induce DC maturation, which was accompanied by elevated expression of MHC and co-stimulatory molecules. The effect of mL2 protein on DC maturation was more remarkable than that of non-mL2 proteins. Uptake of mL2 antigens by DC was more efficient. Furthermore, the T cells can be stimulated to proliferate in vitro and secrete Th1 and Th2 cytokines. Higher levels of both IFN-gamma and IL-10 were detected from the T cells stimulated by mL2-pulsed DC, suggesting a concurrent activation of CD4+ and CD8+ T cells. The results demonstrated that L2 domain of ErbB2 receptor is an immunodominant molecule. The mL2 domain of ErbB2 can induce an enhanced maturation and functional capacity of DC. It may become an effective strategy to induce anti-ErbB2 response.
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Hu K, Zhong G, He F. Expression of estrogen receptors ERalpha and ERbeta in endometrial hyperplasia and adenocarcinoma. Int J Gynecol Cancer 2005; 15:537-41. [PMID: 15882182 DOI: 10.1111/j.1525-1438.2005.15321.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
We assessed the expression of estrogen receptors (ER)alpha and ERbeta in 114 human endometrial hyperplasia and adenocarcinomas. The aim of this study was to determine the expression of both ER isoforms in human endometrial tissue by immunohistochemistry. From normal proliferation to simple and complex hyperplasia, the expression of ERalpha was increased (P < 0.05), while ERbeta did not change much (P > 0.05). In atypia hyperplasia and adenocarcinoma, both ERalpha and ERbeta were decreased significantly (P < 0.05). Most endometrial adenocarcinomas expressed ERalpha, either alone or in combination with ERbeta, and the ERbeta/ERalpha ratio was decreased when compared to normal proliferation (P < 0.05). Also, we found that the expression of ERalpha and ERbeta has no relationship with the status of lymph node of adenocarcinoma (P > 0.05). Both ERalpha and ERbeta play an important role in endometrial hyperplasia and carcinomas, the levels of ERalpha and ERbeta appear be used as prognostic indicators.
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Hu K, Zhong G, He F. Expression of estrogen receptors ERα and ERβ in endometrial hyperplasia and adenocarcinoma. Int J Gynecol Cancer 2005. [DOI: 10.1136/ijgc-00009577-200505000-00020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
We assessed the expression of estrogen receptors (ER)α and ERβ in 114 human endometrial hyperplasia and adenocarcinomas. The aim of this study was to determine the expression of both ER isoforms in human endometrial tissue by immunohistochemistry. From normal proliferation to simple and complex hyperplasia, the expression of ERα was increased (P < 0.05), while ERβ did not change much (P > 0.05). In atypia hyperplasia and adenocarcinoma, both ERα and ERβ were decreased significantly (P < 0.05). Most endometrial adenocarcinomas expressed ERα, either alone or in combination with ERβ, and the ERβ/ERα ratio was decreased when compared to normal proliferation (P < 0.05). Also, we found that the expression of ERα and ERβ has no relationship with the status of lymph node of adenocarcinoma (P > 0.05). Both ERα and ERβ play an important role in endometrial hyperplasia and carcinomas, the levels of ERα and ERβ appear be used as prognostic indicators.
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Zhong G, Tachiki M, Umezawa H, Fujisaki T, Kawarada H, Ohdomari I. Large-Area Synthesis of Carbon Nanofibers by Low-Power Microwave Plasma-Assisted CVD. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/cvde.200304168] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Prifti S, Lelle I, Zhong G, Strowitzki T, Rabe T. Matrix metalloproteinase 2 and tissue inhibitor of metalloproteinase 2 expression is not regulated by norgestimate or norelgestromin. Gynecol Endocrinol 2004; 18:23-7. [PMID: 15106361 DOI: 10.1080/09513590310001651740] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Steroid hormones regulate endometrial expression of matrix metalloproteinases (MMPs) and their inhibitors. Synthetic progestins are widely used in oral contraceptives and for hormone replacement therapy. To assess whether the synthetic progestins norgestimate and its derivative norelgestromin (17-deacetylnorgestimate) modulate the expression of MMPs, Ishikawa endometrial cancer cells were separately treated with 17 beta-estradiol, 17 alpha-hydroxyprogesterone, norgestimate and norelgestromin. Culture supernatants were assayed for MMPs 2, 3 and 9, and for tissue inhibitors of MMPs (TIMP-1 and TIMP-2) by enzyme-linked immunosorbent assays (ELISAs). No marked modulation of MMP-2 and TIMP-2 expression was observed upon incubation of the cells with the synthetic progestins. By ELISA, neither MMP-3 or MMP-9 nor TIMP-1 immunoreactivity was detected. Interestingly, TIMP-2 expression was down-regulated by 17 beta-estradiol and 17 alpha-hydroxyprogesterone.
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Zhong G, Mantel PL, Jiang X, Jarry-Guichard T, Gros D, Labarrere C, Moreno AP. LacSwitch II regulation of connexin43 cDNA expression enables gap-junction single-channel analysis. Biotechniques 2003; 34:1034-9, 1041-4, 1046. [PMID: 12765030 DOI: 10.2144/03345rr03] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Metabolic and electrical coupling through gap junction channels is implicated in cell differentiation, tissue homeostasis, and electrotonic propagation of signals in excitable tissues. The characterization of gating properties of these channels requires electrophysiological recordings at both single- and multiple-channel levels. Hence, a system that is able to control connexin expression by external means would provide a useful tool. To regulate the expression of connexins in cells, plasmids encoding a transactivator and/or a lac-operon IPTG response-dependent Cx43 target gene were transfected into communication-deficient N2a neuroblastoma cells. Immunoblotting, dye coupling, and electrophysiological methods revealed that expression of Cx43 in selected clones could be tightly regulated. After 15-20 h of acute induction with IPTG, cell-to-cell communication reached its peak with junctional conductances of 15-30 nS. Chronic induction at specific doses of IPTG produced constant, controlled levels of Cx43 expression, which were reflected by predictable junctional coupling levels. These conditions allowed prolonged recordings from either lowly or highly coupled cells, making lac operon an ideal regulatory system for channel gating studies at a single-channel level.
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Wan F, Zhong G, Liu L. [A textual research on drinking disease and antidrinking remedies]. ZHONGHUA YI SHI ZA ZHI (BEIJING, CHINA : 1980) 2001; 24:203-6. [PMID: 11613253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
This subject is investigated through three aspects, viz., definition of drinking disease, its manifestations and treatment, and recipes and drug for antidrinking. The term "drinking disease" (Jiu Bing) was first recorded in Wang Shuhe's Canon of Pulsology, while abnormal drinking (Jiu Bo) was mentioned in Miraculous Pivot (Ling Shu). On Pathogenesis Manifestation of all diseases (Zhu Bing Yuan Hou Lun) gives the pathology and etiology. Great influence was exerted from Jin-yuan dynasties concerning its treatment. Zhang Jiebin expounded the comatous syndrome due to drinking (Jiu Jue). The earliest antidrinking drug was recorded in Shen Nong's Classic of Herbology. Through investigation, the commonly applied drug for relieving drunk include Flos Puerariae, Fructus Hovenariae, while the famous recipe for relieving drunk is Anti-tipsy Decoction of Flos Puerariae.
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Wolf K, Fischer E, Mead D, Zhong G, Peeling R, Whitmire B, Caldwell HD. Chlamydia pneumoniae major outer membrane protein is a surface-exposed antigen that elicits antibodies primarily directed against conformation-dependent determinants. Infect Immun 2001; 69:3082-91. [PMID: 11292727 PMCID: PMC98263 DOI: 10.1128/iai.69.5.3082-3091.2001] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The major outer membrane protein (MOMP) of Chlamydia trachomatis serovariants is known to be an immunodominant surface antigen. Moreover, it is known that the C. trachomatis MOMP elicits antibodies that recognize both linear and conformational antigenic determinants. In contrast, it has been reported that the MOMP of Chlamydia pneumoniae is not surface exposed and is immunorecessive. We hypothesized that the discrepancies between C. trachomatis and C. pneumoniae MOMP exposure on intact chlamydiae and immunogenic properties might be because the focus of the host's immune response is directed to conformational epitopes of the C. pneumoniae MOMP. We therefore conducted studies aimed at defining the surface exposure of MOMP and the conformational dominance of MOMP antibodies. We present here a description of C. pneumoniae species-specific monoclonal antibody (MAb), GZD1E8, which recognizes a conformational epitope on the surface of C. pneumoniae. This MAb is potent in the neutralization of C. pneumoniae infectivity in vitro. Another previously described C. pneumoniae species-specific monoclonal antibody, RR-402, displayed very similar characteristics. However, the antigenic determinant recognized by RR-402 has yet to be identified. We show by immunoprecipitation of C. pneumoniae with GZD1E8 and RR-402 MAbs and by mass spectrometry analysis of immunoprecipitated proteins that both antibodies GZD1E8 and RR-402 recognize the MOMP of C. pneumoniae and that this protein is localized on the surface of the organism. We also show that human sera from C. pneumoniae-positive donors consistently recognize the MOMP by immunoprecipitation, indicating that the MOMP of C. pneumoniae is an immunogenic protein. These findings have potential implications for both C. pneumoniae vaccine and diagnostic assay development.
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Zhong G, Fan P, Ji H, Dong F, Huang Y. Identification of a chlamydial protease-like activity factor responsible for the degradation of host transcription factors. J Exp Med 2001; 193:935-42. [PMID: 11304554 PMCID: PMC2193410 DOI: 10.1084/jem.193.8.935] [Citation(s) in RCA: 293] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Microbial pathogens have been selected for the capacity to evade or manipulate host responses in order to survive after infection. Chlamydia, an obligate intracellular pathogen and the causative agent for many human diseases, can escape T lymphocyte immune recognition by degrading host transcription factors required for major histocompatibility complex (MHC) antigen expression. We have now identified a chlamydial protease- or proteasome-like activity factor (CPAF) that is secreted into the host cell cytosol and that is both necessary and sufficient for the degradation of host transcription factors RFX5 and upstream stimulation factor 1 (USF-1). The CPAF gene is highly conserved among chlamydial strains, but has no significant overall homology with other known genes. Thus, CPAF represents a unique secreted protein produced by an obligate intracellular bacterial pathogen to interfere with effective host adaptive immunity.
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Liu L, Hu H, Ji H, Murdin AD, Pierce GN, Zhong G. Chlamydia pneumoniae infection significantly exacerbates aortic atherosclerosis in an LDLR-/- mouse model within six months. Mol Cell Biochem 2000; 215:123-8. [PMID: 11204447 DOI: 10.1023/a:1026531506202] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We have previously shown that infection with the C. pneumoniae AR39 strain once monthly for 9 consecutive months significantly exacerbated atherosclerosis in mice with LDL receptor deficiency (LDLR-/-) in the presence of a high cholesterol diet. To further optimize the LDLR-/- mouse model for studying the mechanisms of C. pneumoniae atherogenesis, we have tested a different infection protocol with intranasal inoculation twice monthly for 6 consecutive months in the present study. We found that C. pneumoniae infection for 6 months was sufficient to produce a 130%, significantly greater exacerbation of aortic atherosclerosis in LDLR-/- mice in the presence of a high cholesterol diet. Mice receiving a high cholesterol diet alone displayed a lesion area index of 18.2 +/- 6.1 (S.D.) while mice treated with both the high cholesterol diet and C. pneumoniae infection had a lesion area index of 41.8 +/- 15.2 (S.D.). However, the chlamydial infection did not significantly alter the mouse serum total cholesterol or the LDL levels induced by the high cholesterol diet. This study not only confirms our previous findings that C. pneumoniae infection can exacerbate aortic atherosclerosis lesion in the LDLR-/- mice, but also further optimizes the LDLR-/- mouse model for future mechanism studies.
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Kobor MS, Simon LD, Omichinski J, Zhong G, Archambault J, Greenblatt J. A motif shared by TFIIF and TFIIB mediates their interaction with the RNA polymerase II carboxy-terminal domain phosphatase Fcp1p in Saccharomyces cerevisiae. Mol Cell Biol 2000; 20:7438-49. [PMID: 11003641 PMCID: PMC86297 DOI: 10.1128/mcb.20.20.7438-7449.2000] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transcription by RNA polymerase II is accompanied by cyclic phosphorylation and dephosphorylation of the carboxy-terminal heptapeptide repeat domain (CTD) of its largest subunit. We have used deletion and point mutations in Fcp1p, a TFIIF-interacting CTD phosphatase, to show that the integrity of its BRCT domain, like that of its catalytic domain, is important for cell viability, mRNA synthesis, and CTD dephosphorylation in vivo. Although regions of Fcp1p carboxy terminal to its BRCT domain and at its amino terminus were not essential for viability, deletion of either of these regions affected the phosphorylation state of the CTD. Two portions of this carboxy-terminal region of Fcp1p bound directly to the first cyclin-like repeat in the core domain of the general transcription factor TFIIB, as well as to the RAP74 subunit of TFIIF. These regulatory interactions with Fcp1p involved closely related amino acid sequence motifs in TFIIB and RAP74. Mutating the Fcp1p-binding motif KEFGK in the RAP74 (Tfg1p) subunit of TFIIF to EEFGE led to both synthetic phenotypes in certain fcp1 tfg1 double mutants and a reduced ability of Fcp1p to activate transcription when it is artificially tethered to a promoter. These results suggest strongly that this KEFGK motif in RAP74 mediates its interaction with Fcp1p in vivo.
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Fong IW, Quinn T, Blessing E, Kuo C, Malinverni R, Lauer M, Mawhorter S, Bachmaier K, Rosenfeld M, Taylor C, Zhong G. Collaborative multidisciplinary workshop report: what questions regarding the role of Chlamydia pneumoniae in atherosclerosis and cardiovascular disease need to be addressed utilizing animal models? J Infect Dis 2000; 181 Suppl 3:S519-20. [PMID: 10839751 DOI: 10.1086/315637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Zhong G, Ma Q, Shao Z. [Inner-hemangioma ligation and pingyangmycin injection in hemangioma (with 30 cases report)]. ZHONGHUA ZHENG XING WAI KE ZA ZHI = ZHONGHUA ZHENGXING WAIKE ZAZHI = CHINESE JOURNAL OF PLASTIC SURGERY 2000; 16:133-5. [PMID: 11593684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
OBJECTIVE To provide a simple and safe surgical approach in treating cavernous and racemose hemangioma. METHODS First cross-ligate the hemangioma, as to divide the tumor into independent compartments, them inject pingyangmycin into the compartments respectively. RESULTS There are 30 cases in this group (35 hemangiomas). Twenty-four cases (28 hemangiomas) were totally cured, accounting for 80%; Six cases were improved (7 hemangiomas) for 20%; There was no ineffective case. CONCLUSION "Inner-hemangioma ligation and injection of pingyangmycin" has broad surgical indications, with desirable outcome in treating cavernous and racemose hemangioma, especially those unsuitable for surgery, or ineffective simply by inner-hemangioma injection.
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Zhong G, Liu L, Fan T, Fan P, Ji H. Degradation of transcription factor RFX5 during the inhibition of both constitutive and interferon gamma-inducible major histocompatibility complex class I expression in chlamydia-infected cells. J Exp Med 2000; 191:1525-34. [PMID: 10790427 PMCID: PMC2213440 DOI: 10.1084/jem.191.9.1525] [Citation(s) in RCA: 160] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
We have previously shown that the obligate intracellular pathogen chlamydia can suppress interferon (IFN)-gamma-inducible major histocompatibility complex (MHC) class II expression in infected cells by degrading upstream stimulation factor (USF)-1. We now report that chlamydia can also inhibit both constitutive and IFN-gamma-inducible MHC class I expression in the infected cells. The inhibition of MHC class I molecule expression correlates well with degradation of RFX5, an essential downstream transcription factor required for both the constitutive and IFN-gamma-inducible MHC class I expression. We further demonstrate that a lactacystin-sensitive proteasome-like activity identified in chlamydia-infected cell cytosolic fraction can degrade both USF-1 and RFX5. This proteasome-like activity is dependent on chlamydial but not host protein synthesis. Host preexisting proteasomes may not be required for the unique proteasome-like activity. These observations suggest that chlamydia-secreted factors may directly participate in the proteasome-like activity. Efforts to identify the chlamydial factors are underway. These findings provide novel information on the molecular mechanisms of chlamydial evasion of host immune recognition.
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Karlstrom A, Zhong G, Rader C, Larsen NA, Heine A, Fuller R, List B, Tanaka F, Wilson IA, Barbas CF, Lerner RA. Using antibody catalysis to study the outcome of multiple evolutionary trials of a chemical task. Proc Natl Acad Sci U S A 2000; 97:3878-83. [PMID: 10760259 PMCID: PMC18110 DOI: 10.1073/pnas.97.8.3878] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Catalytic aldolase antibodies generated by immunization with two different, but structurally related, beta-diketone haptens were cloned and sequenced to study similarities and differences between independently evolved catalysts. Kinetic and sequence analysis coupled with mutagenesis, structural, and modeling studies reveal that the defining event in the evolution of these catalysts was a somatic mutation that placed a lysine residue in a deep, yet otherwise unrefined, hydrophobic pocket. We suggest that covalent chemistries may be as readily selected from the immune repertoire as the traditional noncovalent interactions that have formed the basis of immunochemistry until this time. Further, we believe that these experiments recapitulate the defining events in the evolution of nature's enzymes, particularly as they relate to chemical mechanism, catalytic promiscuity, and gene duplication.
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