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Gordon W. Gribble

Bio: Gordon W. Gribble is an academic researcher from Dartmouth College. The author has contributed to research in topics: Indole test & Ring (chemistry). The author has an hindex of 63, co-authored 465 publications receiving 15875 citations. Previous affiliations of Gordon W. Gribble include Harvard University & Keene State College.


Papers
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Journal ArticleDOI
TL;DR: This work shows that synthetic triterpenoid analogues of oleanolic acid are extremely potent inducers of the phase 2 response [e.g., elevation of NAD(P)H-quinone oxidoreductase and heme oxygenase 1], which is a major protector of cells against oxidative and electrophile stress.
Abstract: A series of synthetic triterpenoid (TP) analogues of oleanolic acid are powerful inhibitors of cellular inflammatory processes such as the induction by IFN-γ of inducible nitric oxide synthase (iNOS) and of cyclooxygenase 2 in mouse macrophages. Here, we show that these analogues are also extremely potent inducers of the phase 2 response [e.g., elevation of NAD(P)H-quinone oxidoreductase and heme oxygenase 1], which is a major protector of cells against oxidative and electrophile stress. Moreover, like previously identified phase 2 inducers, the TP analogues use the antioxidant response element–Nrf2–Keap1 signaling pathway. Thus, induction of the phase 2 response and suppression of the iNOS induction was abrogated in nrf2–/– and keap1–/– mouse embryonic fibroblasts. The high potency of TP analogues in inducing the phase 2 response and blocking inflammation depends on the presence of activated Michael reaction (enone) functions at critical positions in rings A and C. The most potent TP doubles NAD(P)H–quinone oxidoreductase in murine hepatoma cells at 0.28 nM and has an IC50 for suppression of iNOS induction in primary mouse macrophages of 0.0035 nM. The direct interaction of this TP with thiol groups of the Keap1 sensor for inducers is demonstrated spectroscopically. The antiinflammatory and phase 2 inducer potencies of 18 TP are closely linearly correlated (r2 = 0.91) over 6 orders of magnitude of concentration. Thus, in addition to blocking inflammation and promoting differentiation, these TP exhibit another very important protective property: the induction of the phase 2 response.

582 citations

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TL;DR: More than 3800 organohalogen compounds, mainly containing chlorine or bromine but a few with iodine and fluorine, are produced by living organisms or are formed during natural abiogenic processes, such as volcanoes, forest fires, and other geothermal processes.

527 citations

Journal Article
TL;DR: Inhibitory effects of TP-69 or TP-72 on iNOS formation were not blocked by the glucocorticoid receptor antagonist RU-486, indicating that these triterpenoids do not act through the glucopreventive receptor, nor does TP- 72 act as an iN OS or COX-2 enzyme inhibitor when added to RAW cells in which synthesis of these two enzymes in response to LPS has already been induced.
Abstract: We have synthesized more than 80 novel triterpenoids, all derivatives of oleanolic and ursolic acid, as potential anti-inflammatory and chemopreventive agents. These triterpenoids have been tested for their ability to suppress the de novo formation of two enzymes, inducible nitric oxide synthase (iNOS) and inducible cyclooxygenase (COX-2), using IFN-γ-stimulated primary mouse macrophages or lipopolysaccharide (LPS)-activated RAW 264.7 macrophages as assay systems. Two synthetic oleananes, 3,12-dioxoolean-1-en-28-oic acid (TP-69) and 3,11-dioxoolean-1,12-dien-28-oic acid (TP-72), were highly active inhibitors of de novo formation of both iNOS and COX-2. Both TP-69 and TP-72 blocked the increase in iNOS or COX-2 mRNA induced by IFN-γ or LPS. In addition, TP-72 suppressed NF-κB activation in primary macrophages treated with the combination of IFN-γ and LPS or IFN-γ and tumor necrosis factor. The 3-α(axial)-epimer of ursolic acid suppressed de novo formation of COX-2, in contrast to naturally occurring 3-β(equatorial)-ursolic acid. Inhibitory effects of TP-69 or TP-72 on iNOS formation were not blocked by the glucocorticoid receptor antagonist RU-486, indicating that these triterpenoids do not act through the glucocorticoid receptor, nor does TP-72 act as an iNOS or COX-2 enzyme inhibitor when added to RAW cells in which synthesis of these two enzymes in response to LPS has already been induced. It may be possible to develop triterpenoids as useful agents for chemoprevention of cancer or other chronic diseases with an inflammatory component.

368 citations


Cited by
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28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

Journal ArticleDOI
10 Mar 1970

8,159 citations

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TL;DR: This review covers the literature published in 2014 for marine natural products, with 1116 citations referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms.

4,649 citations

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TL;DR: The median-effect principle and its mass-action law based computer software are gaining increased applications in biomedical sciences, from how to effectively evaluate a single compound or entity to how to beneficially use multiple drugs or modalities in combination therapies.
Abstract: The median-effect equation derived from the mass-action law principle at equilibrium-steady state via mathematical induction and deduction for different reaction sequences and mechanisms and different types of inhibition has been shown to be the unified theory for the Michaelis-Menten equation, Hill equation, Henderson-Hasselbalch equation, and Scatchard equation. It is shown that dose and effect are interchangeable via defined parameters. This general equation for the single drug effect has been extended to the multiple drug effect equation for n drugs. These equations provide the theoretical basis for the combination index (CI)-isobologram equation that allows quantitative determination of drug interactions, where CI 1 indicate synergism, additive effect, and antagonism, respectively. Based on these algorithms, computer software has been developed to allow automated simulation of synergism and antagonism at all dose or effect levels. It displays the dose-effect curve, median-effect plot, combination index plot, isobologram, dose-reduction index plot, and polygonogram for in vitro or in vivo studies. This theoretical development, experimental design, and computerized data analysis have facilitated dose-effect analysis for single drug evaluation or carcinogen and radiation risk assessment, as well as for drug or other entity combinations in a vast field of disciplines of biomedical sciences. In this review, selected examples of applications are given, and step-by-step examples of experimental designs and real data analysis are also illustrated. The merging of the mass-action law principle with mathematical induction-deduction has been proven to be a unique and effective scientific method for general theory development. The median-effect principle and its mass-action law based computer software are gaining increased applications in biomedical sciences, from how to effectively evaluate a single compound or entity to how to beneficially use multiple drugs or modalities in combination therapies.

4,270 citations

Journal ArticleDOI
TL;DR: Introduced to the Market in the Last Decade (2001−2011) Jiang Wang,† María Sańchez-Rosello,́‡,§ Jose ́ Luis Aceña, Carlos del Pozo,‡ and Hong Liu.
Abstract: Introduced to the Market in the Last Decade (2001−2011) Jiang Wang,† María Sańchez-Rosello,́‡,§ Jose ́ Luis Aceña, Carlos del Pozo,‡ Alexander E. Sorochinsky, Santos Fustero,*,‡,§ Vadim A. Soloshonok,* and Hong Liu*,† †Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China ‡Department of Organic Chemistry, Faculty of Pharmacy, University of Valencia, Av. Vicente Andreś Estelleś, 46100 Burjassot, Valencia, Spain Laboratorio de Molećulas Orgańicas, Centro de Investigacioń Príncipe Felipe, C/ Eduardo Primo Yuf́era 3, 46012 Valencia, Spain Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizab́al 3, 20018 San Sebastian, Spain IKERBASQUE, Basque Foundation for Science, Alameda Urquijo, 36-5 Plaza Bizkaia, 48011 Bilbao, Spain Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, Murmanska Street 1, 02660 Kyiv-94, Ukraine

3,368 citations