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Zhao C, Xiao W, Han F, Lu L, Huang S, Wu S, Chen C, Chen J, Lin C, Deng X. Long-term Results and Prognostic Factors of Primary Nasopharyngeal Carcinoma Patients Treated with Intensity Modulated-Radiotherapy. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.1441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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252
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Wang L, Shang H, Liu Y, Zheng M, Wu R, Phillips J, Bartels D, Deng X. A role for a cell wall localized glycine-rich protein in dehydration and rehydration of the resurrection plant Boea hygrometrica. PLANT BIOLOGY (STUTTGART, GERMANY) 2009; 11:837-48. [PMID: 19796361 DOI: 10.1111/j.1438-8677.2008.00187.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The acquisition of desiccation tolerance in dicotyledonous angiosperms requires the induction of a co-ordinated programme of genetic and biochemical processes during drying and the adaptive mechanisms are primarily protoplasmic in nature. Recent studies have shown that changes in cell wall structure and composition are also important for recovery after drying, however, the molecular mechanisms that underpin these adaptive responses are largely unknown. Here, the desiccation-tolerant plant Boea hygrometrica was used as a model system to investigate the changes in gene expression and cell wall adaptation that take place during extreme dehydration. A cDNA macroarry analysis of dehydration-inducible genes led to the identification of a gene encoding a glycine-rich protein (BhGRP1). The corresponding transcript was up-regulated during drying in B. hygrometrica leaves. In silico analysis revealed that BhGRP1 is targeted to the cell wall and this was confirmed in planta. Morphological changes in the cell wall architecture were also observed during the process of drying and re-watering. Concomitant with this observation, cell wall profiling by Fourier transform infrared spectroscopy indicated that protein levels increased upon desiccation and remained broadly similar upon re-watering. These findings suggest that the deposition of BhGRP1 may play a role in cell wall maintenance and repair during dehydration and rehydration in B. hygrometrica.
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Xiao W, Zhao C, Han F, Lu L, Wu S, Deng X, Lu T, Cui N. Concurrent Chemotherapy can Further Improve Clinical Outcome for Stage III Nasopharyngeal Carcinoma Patients Treated with IMRT in Endemic Area. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.1492] [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]
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254
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Xi ZX, Kleitz HK, Deng X, Ladenheim B, Peng XQ, Li X, Gardner EL, Stein EA, Cadet JL. A single high dose of methamphetamine increases cocaine self-administration by depletion of striatal dopamine in rats. Neuroscience 2009; 161:392-402. [PMID: 19336247 PMCID: PMC3737775 DOI: 10.1016/j.neuroscience.2009.03.060] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Revised: 03/20/2009] [Accepted: 03/23/2009] [Indexed: 11/24/2022]
Abstract
Psychostimulant addicts often take high doses of drugs, and high doses of psychostimulants such as methamphetamine (METH) are neurotoxic to striatal dopamine (DA) terminals. Yet, the effects of high doses of METH on drug-seeking and drug-taking behavior have not been examined. In the present study, we found that single high doses of METH in rats (10-20 mg/kg) dose-dependently increased cocaine self-administration under fixed-ratio 2 (FR2) reinforcement conditions, while higher doses (40 mg/kgx1 or 10 mg/kg/2 hx4) caused high mortality among rats maintained on daily cocaine self-administration. The increased cocaine self-administration appeared to be a compensatory response to reduced cocaine reward after METH, because the same doses of METH caused a dose-dependent reduction both in "break-point" levels for cocaine self-administration under progressive-ratio reinforcement and in nucleus accumbens DA response to acute cocaine. Further, METH (10-20 mg/kg) produced large DA release (4000%-6000% over baseline), followed by a significant reduction in striatal DA and 3,4-dihydroxyphenylacetic acid (DOPAC) contents, but without significant changes in striatal DA transporter levels. These findings suggest that the present high doses of METH caused striatal DA depletion or hypofunction without severe damage in DA terminals, which may contribute to the increased cocaine-taking behavior observed in the present study. Provided that the present doses of METH may mimic METH overdose incidents in humans, the present findings suggest that METH-induced DA depletion or neurotoxicity may lead to an increase in subsequent drug-taking and drug-seeking behavior.
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Ahluwalia A, Li A, Cheng G, Deng X, Tarnawski AS. Reduced ghrelin in endothelial cells plays important mechanistic role in aging-related impairment of angiogenesis. JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY : AN OFFICIAL JOURNAL OF THE POLISH PHYSIOLOGICAL SOCIETY 2009; 60:29-34. [PMID: 19617642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Accepted: 04/30/2009] [Indexed: 02/06/2023]
Abstract
Ghrelin, a hormone produced mainly by gastric mucosal cells stimulates growth hormone (GH) release. Ghrelin is also expressed in the endothelial cells of blood vessels suggesting its physiological role and a function in these cells. We recently demonstrated that ghrelin induces angiogenesis--new capillary blood vessel formation- in neonatal human microvascular endothelial cells (HMVECs). Angiogenesis is impaired in aging individuals both in vitro and in vivo, but the precise mechanism(s) of this phenomenon is unknown. We examined whether HMVECs derived from aging individuals (66 years and 90 years old), 66-HMVECs and 90-HMVECs have reduced ghrelin levels vs. neonatal (Neo) HMVECs and whether treatment with exogenous ghrelin can restore impaired in vitro angiogenesis on matrigel in aged HMVECs. Ghrelin levels were reduced in the aged HMVECs by 3.2-fold (p<0.05) compared to Neo-HMVECs. Angiogenesis was significantly decreased in the aged 66- and 90-HMVECs by 39.7% (p = 0.003) and 62.4% (p = 0.003), respectively compared to Neo-HMVECs. Treatment with exogenous ghrelin significantly reversed impaired angiogenesis in aged HMVECs with the EC(50) 0.05 nM. Ghrelin induced angiogenesis in Neo-HMVECs mainly through ERK2 activation. This study is the first demonstration that reduced ghrelin is one of the factors responsible for aging-related impairment of angiogenesis.
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Deng X, Li W, Sun Y, Wei H, Jiang Y, He F. Exploring Rat Plasmatic Proteomes: What Triggered the Liver Regeneration? (Supplementary materials). Protein Pept Lett 2009; 16:698-705. [DOI: 10.2174/092986609788490258] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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257
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Wu S, Deng X, Zhang P, Xie C, Zhang X, Jin Z. Phase II study of postoperative chemoradiotherapy for esophageal carcinoma. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.e15606] [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
e15606 Background: Esophageal squamous cell carcinoma is still a virulent disease diagnosed at late stage and remains a major cause of carcinoma mortality in China. The preoperative chemoradiotherapy had been applied to patients with esophageal carcinoma in an effort to reduce the relapse and improve survival. However, randomized controlled trails have shown conflicting results. Intergroup study 0116 demonstrated that postoperative chemoradiotherapy significantly improved overall survival in gastric carcinoma patients. The question remains whether postoperative chemoradiotherapy can improve overall survival in patients with esophageal carcinoma. Our planning study was to investigate the role of postoperative chemoradiotherapy in the multimodality treatment for locally advanced esophageal carcinoma. Methods: From October 2000 to October 2007, Fifty-two patients who underwent esophagectomy with stage II-III esophageal carcinoma were enrolled. All patients received 50Gy of postoperative radiotherapy over 25 fractions in 5 weeks. Two cycles of chemotherapy (Paclitaxel 135mg/m2 d1,cisplatin 20mg/m2d1–3) were administered concurrently on days 1–3 and days 29–31 of radiotherapy. Results: Of the total 52 patients, 28 (54%) developed grade 3 or 4 toxicity.At the time of analysis, 23 patients died. The median follow-up for surviving patients was 23.5 months. The median survival time was 37.2 months. Incidences of tumor recurrence were 53.8 % (28/52) of patients. As expected, distant metastasis was predominant. The 2-year local-regional control survival, distant metastasis-free survival and relapse-free survival were 60.01%, 71.38% and 42.01%, respectively. 1-year and 3-year overall survival were 82.19% and 47.13%, respectively. Conclusions: This novel postoperative chemoradiation regimen for treatment of patients with stage II-III esophageal cancer has a tolerable toxicity and promising 3-year overall survival. No significant financial relationships to disclose.
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Ouyang X, Deng X. [Survey of toxoplasma infection in fertile age women and children in Urumqi city]. ZHONGGUO JI SHENG CHONG XUE YU JI SHENG CHONG BING ZA ZHI = CHINESE JOURNAL OF PARASITOLOGY & PARASITIC DISEASES 2009; 17:317. [PMID: 12563872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
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259
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Deng X, Guo X, Pang G, Tian X. [Establishment of a rabbit model of Acanthamoeba keratitis]. ZHONGGUO JI SHENG CHONG XUE YU JI SHENG CHONG BING ZA ZHI = CHINESE JOURNAL OF PARASITOLOGY & PARASITIC DISEASES 2009; 17:308-10. [PMID: 12563867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
AIM To establish an animal model of Acanthamoeba keratitis. METHODS Six New Zealand white rabbits were each injected intrastromally with Acanthamoeba suspension 3 days after subconjunctival injection with dexamethasone. RESULTS All of the 6 rabbits developed keratitis. Acanthamoeba protozoa were identified by the methods of corneal scraping with 10% potassium hydroxide wet mount examined under microscope, corneal protozoa culture and pathological section examination. CONCLUSION A rabbit model of Acanthamoeba keratitis was established.
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Radcliffe RA, Erwin VG, Bludeau P, Deng X, Fay T, Floyd KL, Deitrich RA. A major QTL for acute ethanol sensitivity in the alcohol tolerant and non-tolerant selected rat lines. GENES BRAIN AND BEHAVIOR 2009; 8:611-25. [PMID: 19500156 DOI: 10.1111/j.1601-183x.2009.00496.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The Alcohol Tolerant and Alcohol Non-Tolerant rats (AT, ANT) were selectively bred for ethanol-induced ataxia as measured on the inclined plane. Here we report on a quantitative trait locus (QTL) study in an F(2) intercross population derived from inbred AT and ANT (IAT, IANT) and a follow-up study of congenics that were bred to examine one of the mapped QTLs. Over 1200 F(2) offspring were tested for inclined plane sensitivity, acute tolerance on the inclined plane, duration of the loss of righting reflex (LORR) and blood ethanol at regain of the righting reflex (BECRR). F(2) rats that were in the upper and lower 20% for inclined plane sensitivity were genotyped with 78 SSLP markers. Significant QTLs for inclined plane sensitivity were mapped on chromosomes 8 and 20; suggestive QTLs were mapped on chromosomes 1, 2 and 3. Highly significant QTLs for LORR duration (LOD = 12.4) and BECRR (LOD = 5.7) were mapped to the same locus on chromosome 1. Breeding and testing of reciprocal congenic lines confirmed the chromosome 1 LORR/BECRR QTL. A series of recombinant congenic sub-lines were bred to fine-map this QTL. Current results have narrowed the QTL to an interval of between 5 and 20 Mb. We expect to be able to narrow the interval to less than 5 Mb with additional genotyping and continued breeding of recombinant sub-congenic lines.
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261
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Chen J, Pu X, Deng X, Liu S, Li H, Civerolo E. A phytoplasma related to 'Candidatus phytoplasma asteri' detected in citrus showing Huanglongbing (yellow shoot disease) symptoms in Guangdong, P. R. China. PHYTOPATHOLOGY 2009; 99:236-242. [PMID: 19203275 DOI: 10.1094/phyto-99-3-0236] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Citrus huanglongbing (HLB) or yellow shoot disease (i.e., greening disease) is highly destructive to citrus production worldwide. Understanding the etiology of HLB is critical for managing the disease. HLB is currently associated with infection by 'Candidatus Liberibacter spp.' around the world, including China. However, Koch's postulates have not been fulfilled. In addition, other plant pathogens also may be involved in HLB. In a survey performed in Guangdong Province, P. R. China in 2006 and 2007, 141 citrus samples showing typical symptoms of HLB from 11 different cities were collected. Polymerase chain reaction (PCR) using phytoplasma-specific primer sets fU5/rU3 nested with primer set P1/P7 identified 110 (78.0%) positive samples. A 1,785-bp amplicon was obtained with primer set P1/P7. Analysis showed a 100% identity of this sequence in the region of 16S rDNA and 16S-23S rRNA intergenic transcribed spacer to three strains of 'Candidatus Phytoplasma asteri' (onion yellows [Japan], aster yellows 'watercress' [Hawaii], and valeriana yellows [Lithuania]). Of the 141 samples, 89 (63.1%) samples were positive for 'Ca. Liberibacter asiaticus'. When mixed infection was considered, 69 (48.9%) samples were positive for both 'Ca. P. asteri' and 'Ca. L. asiaticus'. Transmission electron microscopy (TEM) showed low titers of both walled and wall-less bodies in the phloem sieve tubes of HLB citrus. When transmission from symptomatic citrus to periwinkle (Catharanthus roseus) via dodder (Cuscuta campestris) was conducted, both phytoplasma and 'Ca. L. asiaticus' were detected from the affected periwinkle. In addition to yellowing/mottling, the infected periwinkle showed symptoms of virescence and phyllody which are commonly associated with phytoplasmal diseases. TEM analysis of affected periwinkle revealed pleomorphic and wall-less organisms, characteristic of phytoplasmas, filling some phloem sieve tubes. In contrast, walled bacteria were at low titer. This study showed that in addition to 'Ca. L. asiaticus', a phytoplasma related to 'Ca. P. asteri' could also be detected in citrus showing HLB symptoms in Guangdong.
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Cao Y, Liu X, Zhang W, Deng X, Zhang H, Liu Y, Chen L, Thompson EA, Townsend CM, Ko TC. TGF-beta repression of Id2 induces apoptosis in gut epithelial cells. Oncogene 2009; 28:1089-98. [PMID: 19137015 DOI: 10.1038/onc.2008.456] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Transforming growth factor-beta (TGF-beta) regulates epithelial tissue homeostasis by activating processes that control cell cycle arrest, differentiation and apoptosis. Disruption of the TGF-beta signaling pathway often occurs in colorectal cancers. Earlier, we have shown that TGF-beta induces apoptosis through the transcription factor Smad3. Affymetrix oligonucleotide microarrays were used to identify TGF-beta/Smad3 target genes that regulate apoptosis in rat intestinal epithelial cells (RIE-1). We found that TGF-beta repressed the expression of the inhibitor of differentiation (Id) gene family. Knockdown of Id1 and Id2 gene expression induced apoptosis in RIE-1 cells, whereas overexpression of Id2 attenuated TGF-beta-induced apoptosis. TranSignal Protein/DNA arrays were used to identify the hypoxia-inducing factor-1 (HIF-1) as a downstream target of TGF-beta. HIF-1 is a basic helix-loop-helix protein, and overexpression of Id2 blocked HIF-1 activation by TGF-beta. Furthermore, knockdown of HIF-1 blocked TGF-beta-induced apoptosis. Thus, we have identified HIF-1 as a novel mediator downstream of Id2 in the pathway of TGF-beta-induced apoptosis.
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263
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Tamai R, Deng X, Kiyoura Y. Porphyromonas gingivalis with either Tannerella forsythia or Treponema denticola induces synergistic IL-6 production by murine macrophage-like J774.1 cells. Anaerobe 2009; 15:87-90. [PMID: 19162208 DOI: 10.1016/j.anaerobe.2008.12.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Revised: 09/22/2008] [Accepted: 12/23/2008] [Indexed: 11/15/2022]
Abstract
BACKGROUND Chronic periodontitis is caused by mixed bacterial infection. Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola are frequently detected in deep periodontal pockets. We demonstrate that these bacteria induce proinflammatory cytokine production by the mouse macrophage-like cell line J774.1. MATERIALS AND METHODS J774.1 cells were incubated with and without bacteria for 24h in 96-well flat-bottomed plates. The culture supernatants were analyzed by enzyme-linked immunosorbent assay for secreted mouse interleukin (IL)-6, monocyte chemoattractant protein-1, IL-23, IL-1 beta and tumor necrosis factor-alpha. The cytokine concentrations were determined using a standard curve prepared for each assay. RESULTS Mixed infection with P. gingivalis and either T. forsythia or T. denticola at 10(5)CFU/ml acted synergistically to increase IL-6 production, but not monocyte chemoattractant protein-1, IL-23, IL-1 beta or tumor necrosis factor-alpha production. Gingipain inhibitors KYT-1 and KYT-36 inhibited IL-6 production by J774.1 cells incubated with 10(5)CFU/ml of mixed bacteria. CONCLUSION These results suggest that P. gingivalis with either T. forsythia or T. denticola directly induces synergistic IL-6 protein production and that gingipains play a role in this synergistic effect.
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Xing L, Sun X, Deng X, Koutcher J, Ling C, Li G. Triple Suicide Gene Therapy Radiosensitizes Prostate Cancer Cells. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.511] [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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265
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Sheng J, Li J, Sheng G, Yu H, Huang H, Cao H, Lu Y, Deng X. Characterization ofrpoBmutations associated with rifampin resistance inMycobacterium tuberculosisfrom eastern China. J Appl Microbiol 2008; 105:904-11. [DOI: 10.1111/j.1365-2672.2008.03815.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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266
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Quiller RG, Baker TA, Deng X, Colling ME, Min BK, Friend CM. Transient hydroxyl formation from water on oxygen-covered Au(111). J Chem Phys 2008; 129:064702. [PMID: 18715097 DOI: 10.1063/1.2965821] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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267
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Hartert TV, Deng X, Hartman TJ, Wen W, Yang G, Gao YT, Jin M, Bai C, Gross M, Roberts LJ, Sheller JR, Christman J, Dupont W, Griffin M, Shu XO. The Shanghai Women's Asthma and Allergy Study: objectives, design, and recruitment results. Am J Epidemiol 2008; 167:1387-96. [PMID: 18397914 PMCID: PMC2430736 DOI: 10.1093/aje/kwn057] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The Shanghai Women's Asthma and Allergy Study is the first population-based incidence study designed to assess the associations of dietary antioxidant intake and measures of oxidative stress and antioxidant enzyme activity with development of adult-onset asthma and allergic rhinitis. A total of 65,732 participants in the Shanghai Women's Health Study, an ongoing cohort study in seven districts of Shanghai, People's Republic of China, were recruited to the Shanghai Women's Asthma and Allergy Study from 2003 to 2007. Dietary intake was assessed in the parent study by using a validated and quantitative food frequency questionnaire at baseline recruitment and at the first biennial follow-up survey. Blood and urine samples were collected to measure baseline oxidative stress, antioxidant enzyme activity, and nutrient levels at the baseline survey. Incident asthma and allergic rhinitis were assessed by using a modification of the International Study of Asthma and Allergies in Childhood questionnaire during the biennial in-person survey of the Shanghai Women's Health Study. Diagnosis of asthma was confirmed by either methacholine challenge testing or test of reversibility to beta-agonists. Dietary antioxidant intake, plasma antioxidants, antioxidant enzymes, and urinary isoprostanes, a marker of oxidative stress, were measured prior to disease onset. This paper describes the study objectives, design, population demographics, and recruitment results.
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268
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Deng X, Hu ZL, Yi XE. Continuous treatment process of mercury removal from aqueous solution by growing recombinant E. coli cells and modeling study. JOURNAL OF HAZARDOUS MATERIALS 2008; 153:487-492. [PMID: 17920767 DOI: 10.1016/j.jhazmat.2007.08.080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Revised: 08/29/2007] [Accepted: 08/29/2007] [Indexed: 05/25/2023]
Abstract
A continuous treatment process was developed to investigate the capability of genetically engineered E. coli to simultaneously accumulate mercuric ions and reproduce itself in a continuous stirred tank reactor (CSTR) system. The influence of dilution rate and initial Hg(2+) concentration on continuous process was evaluated. Results indicated that the recombinant E. coli could effectively accumulate Hg(2+) from aqueous solution with Hg(2+) removal ratio up to about 90%, and propagate its cells at the same time in the continuous treatment system under suitable operational conditions. A kinetic model based on mass balance of Hg(2+) was proposed to simulate the continuous process. The modeling results were in good agreement with the experimental data.
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Takamori K, Hosokawa R, Xu X, Deng X, Bringas P, Chai Y. Epithelial fibroblast growth factor receptor 1 regulates enamel formation. J Dent Res 2008; 87:238-43. [PMID: 18296607 DOI: 10.1177/154405910808700307] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The interaction between epithelial and mesenchymal tissues plays a critical role in the development of organs such as teeth, lungs, and hair. During tooth development, fibroblast growth factor (FGF) signaling is critical for regulating reciprocal epithelial and mesenchymal interactions. FGF signaling requires FGF ligands and their receptors (FGFRs). In this study, we investigated the role of epithelial FGF signaling in tooth development, using the Cre-loxp system to create tissue-specific inactivation of Fgfr1 in mice. In K14-Cre;Fgfr1(fl/fl) mice, the apical sides of enamel-secreting ameloblasts failed to adhere properly to each other, although ameloblast differentiation was unaffected at early stages. Prior to eruption, enamel structure was compromised in the K14-Cre;Fgfr1(fl/fl) mice and displayed severe enamel defects that mimic amelogenesis imperfecta (AI), with a rough, irregular enamel surface. These results suggest that there is a cell-autonomous requirement for FGF signaling in the dental epithelium during enamel formation. Loss of Fgfr1 affects ameloblast organization at the enamel-secretory stage and, hence, the formation of enamel.
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Deng X, Chen J, Feng Z, Shan Z, Guo H, Zhu J, Li H, Civerolo EL. Identification and Characterization of the Huanglongbing Bacterium in Pummelo from Multiple Locations in Guangdong, P. R. China. PLANT DISEASE 2008; 92:513-518. [PMID: 30769653 DOI: 10.1094/pdis-92-4-0513] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Huanglongbing (HLB, yellow shoot disease, ex. citrus greening disease), caused by Candidatus Liberibacter spp., is highly destructive to citrus production in Asia, Africa, and South America. Although primarily affecting sweet orange and mandarin, HLB has long been observed in pummelo in Guangdong Province, People's Republic of China; however, the disease in pummelo has received little research attention. Accordingly, it remains unclear how closely related the strains of Ca. Liberibacter in pummelo are to those in other citrus species. In this study, the loci of 16S rDNA, rplAJ (β-operon of ribosomal protein), and an outer membrane protein (omp) gene were analyzed and characterized among strains of Ca. Liberibacter in pummelo samples from six different locations in Guangdong. Sequence comparisons indicated that 'Candidatus Liberibacter asiaticus', but not 'Ca. Liberibacter africanus' or 'Ca. Liberibacter americanus', was exclusively associated with HLB symptoms in pummelo. The pummelo strains of 'Ca. Liberibacter asiaticus' from Guangdong were highly homogeneous. Analyses of single-nucleotide polymorphisms in the omp locus showed that the Guangdong pummelo strains grouped with 'Ca. Liberibacter asiaticus' strains from Thailand, Nepal, and an unspecified location in China but differed from the Philippine and China-Behai strains. Based on the sequence homogeneity at the omp locus, the history of pummelo culture and the means by which HLB is known to be spread, we believe that, likely, the pummelo strain of 'Ca. Liberibacter asiaticus' recently was spread to pummelo in the study areas from infected sweet orange or mandarin trees by insect vectors or by propagation of pummelo infected elsewhere.
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Li S, Deng X, Jiang F, Zhao Y, Xiao W, Kuang X, Sun X. Design and Synthesis of Novel Diaryl Heterocyclic Derivatives as Selective Cyclooxygenase-2. LETT DRUG DES DISCOV 2008. [DOI: 10.2174/157018008783928517] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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272
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Deng X, Lou Z, Feng Z, Li H, Chen J, Civerolo EL. First Report of 'Candidatus Liberibacter asiaticus' from Atalantia buxifolia in Guangdong, China. PLANT DISEASE 2008; 92:314. [PMID: 30769397 DOI: 10.1094/pdis-92-2-0314c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Atalantia buxifolia (Poir.) Oliv., synonym Severinia buxifolia (Poir.) Ten. as commonly found in literature, is a common landscape plant and a popular Chinese medicinal herb known as Jiubingle or Dongfengjie. It remains unclear if this rutaceous plant could host 'Candidatus Liberibacter asiaticus', the pathogen of citrus Huanglongbing (HLB) in Guangdong, P. R. China. This information is important for HLB control in citrus because infected A. buxifolia could serve as a source of inoculum. In August of 1994, three A. buxifolia plants adjacent to a citrus experimental orchard of the South China Agricultural University at Guangzhou were found showing leaf mottle/yellowing symptoms. Two buds from each plant were grafted onto three mandarin trees (Citrus reticulata cv. Pongan) in a psyllid-proof screenhouse for indexing. By October of 1995, typical leaf mottle symptoms were observed in all three grafted trees compared with a healthy control. In March of 1996, one of the A. buxifolia plants was transferred to a screenhouse and has been maintained there. The leaf mottle/yellowing symptoms persisted but did not significantly affect plant growth. DNA was extracted from leaf samples in October 2006 by using the CTAB (cetyltrimethylammoniumbromide) method and assayed by nested-PCR using the general bacterial 16S rDNA primer set fDl/rD1 as the first round of amplification and primer set OI1/OI2c as second round amplification (1,3). After agarose gel electrophoresis and staining with ethidium bromide, an approximate 1.1-kb DNA band was detected in symptomatic samples but not healthy leaf samples of A. buxifolia and C. reticulata. XbaI digestion of the amplicons yielded approximate 500- and 600-bp fragments, characteristic of 'Ca. L. asiaticus'. Similarly, a standard PCR with primer set A5/J2 (3) yielded an approximate 700-bp DNA band characteristic of 'Ca. L. asiaticus' from symptomatic samples only. To our knowledge, this is the first report of graft transmission and PCR detection of 'Ca. L. asiaticus' from A. buxifolia in Guangdong, P. R. China. This work also confirms the findings from Taiwan (2) that A. buxifolia could serve as a source of 'Ca. L. asiaticus'. References: (1) X. Deng et al. Online publication. doi:10.1094/PHP-2007-0419-01-BR. Plant Health Progress, 2007. (2) T.-H. Hung et al. Eur. J. Plant Pathol. 107:183, 2001. (3) S. Jagoueix et al. Mol. Cell. Probes 10:43, 1996.
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Xing L, Deng X, Gade T, Ling C, Koutcher J, Li G. Combination of Cytosine Deaminase With Uracil Phosphoribosyl Transferase With 5-fluorocytosine Radiosensitizes Rat Prostate Cancer Cells. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.1939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Zhang Y, Deng X, Zhou Z, Ren L, Meng Q. Effects of processing maize grains and soyabean
on rumen fermentation and development
of Holstein bull calves. JOURNAL OF ANIMAL AND FEED SCIENCES 2007. [DOI: 10.22358/jafs/74599/2007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Deng X, Zhou G, Li H, Chen J, Civerolo EL. Nested-PCR Detection and Sequence Confirmation of 'Candidatus Liberibacter asiaticus' from Murraya paniculata in Guangdong, China. PLANT DISEASE 2007; 91:1051. [PMID: 30780443 DOI: 10.1094/pdis-91-8-1051c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Murraya paniculata (orange jasmine) is a popular ornamental rutaceaous plant and is known to be a preferred host for the Asian citrus psyllid, Diaphorina citri (Kuwayana), the primary vector of 'Candidatus Liberibacter spp.' that causes citrus Huanglongbing (HLB). HLB is a highly destructive citrus disease worldwide. However, the presence of 'Ca. Liberibacter spp.' in M. paniculata remains uncertain (2). Clarification of M. paniculata as a host of 'Ca. Liberibacter spp.' has direct impact on HLB control programs. During June of 2006, we identified three M. paniculata trees near a mandarin orchard affected by HLB in Luoding City and two trees from Guangzhou City, Guangdong Province, People's Republic of China. All trees had leaves showing yellowing and mottling symptoms characteristic of HLB. Both symptomatic and asymptomatic leaves were collected. DNA was extracted using the CTAB (cetyltrimethylammoniumbromide) method and assayed by nested-PCR. The general bacterial 16S rDNA primer set fDl/rD1 (3) was used for the first round of amplification. Amplification was conducted as previously described (1), and 2 μl of PCR reaction product were used for a second round of amplification using the same procedure but with 35 PCR cycles with primer set OI1/OI2c (3,4). After agarose gel electrophoresis and staining with ethidium bromide, a 1.1-kb DNA band was unambiguously associated with symptomatic but not asymptomatic leaf samples. Nonnested-PCR using primer set OI1/OI2c alone did not yield a target DNA band or yielded a very weak DNA band. XbaI digestion of the nested-PCR DNA product yielded two fragments, 520 and 640 bp long, characteristic of 'Ca. L. asiaticus'. PCR amplicons were sequenced and were 1,095 bp long. This sequence shared >98% similarity to sequences of 'Ca. L. asiaticus' in the GenBank database. We observed that nested-PCR is necessary for consistent amplification of DNA from 'Ca. L. asiaticus' from M. paniculata. We excluded the possible nonspecific amplification associated with nested-PCR by XbaI restriction enzyme digestion and by nucleotide sequence analysis. Our data indicate that M. paniculata is a host of 'Ca. L. asiaticus' but the bacterial titer might be low. References: (1) X. Deng et al. Online publication. doi:10.1094/PHP-2007-0419-01-BR. Plant Health Progress, 2007. (2) M. Garnier and J. Bove. Huanglongbing (Greening). Page 46 in: Compendium of Citrus Diseases. 2nd ed. L. W. Timmer et al., eds. The American Phytopathological Society, St. Paul, MN, 2000. (3) S. Jagoueix et al. Int. J. Syst. Bacteriol. 44:379, 1994. (4) S. Jagoueix et al. Mol. Cell. Probes 10:43, 1996.
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