Nelson D

References (8)

Title : Galanthamine plus estradiol treatment enhances cognitive performance in aged ovariectomized rats - Gibbs_2011_Horm.Behav_60_607
Author(s) : Gibbs RB , Chipman AM , Hammond R , Nelson D
Ref : Horm Behav , 60 :607 , 2011
Abstract : We hypothesize that beneficial effects of estradiol on cognitive performance diminish with age and time following menopause due to a progressive decline in basal forebrain cholinergic function. This study tested whether galanthamine, a cholinesterase inhibitor used to treat memory impairment associated with Alzheimer's disease, could enhance or restore estradiol effects on cognitive performance in aged rats that had been ovariectomized in middle-age. Rats were ovariectomized at 16-17 months of age. At 21-22 months of age rats began receiving daily injections of galanthamine (5mg/day) or vehicle. After one week, half of each group also received 17ss-estradiol administered subcutaneously. Rats were then trained on a delayed matching to position (DMP) T-maze task, followed by an operant stimulus discrimination/reversal learning task. Treatment with galanthamine+estradiol significantly enhanced the rate of DMP acquisition and improved short-term delay-dependent spatial memory performance. Treatment with galanthamine or estradiol alone was without significant effect. Effects were task-specific in that galanthamine+estradiol treatment did not significantly improve performance on the stimulus discrimination/reversal learning task. In fact, estradiol was associated with a significant increase in incorrect responses on this task after reversal of the stimulus contingency. In addition, treatments did not significantly affect hippocampal choline acetyltransferase activity or acetylcholine release. This may be an effect of age, or possibly is related to compensatory changes associated with long-term cholinesterase inhibitor treatment. The data suggest that treating with a cholinesterase inhibitor can enhance the effects of estradiol on acquisition of a DMP task by old rats following a long period of hormone deprivation. This could be of particular benefit to older women who have not used hormone therapy for many years and are beginning to show signs of mild cognitive impairment. Potential mechanisms for these effects are discussed.
ESTHER : Gibbs_2011_Horm.Behav_60_607
PubMedSearch : Gibbs_2011_Horm.Behav_60_607
PubMedID: 21889940

Title : Donepezil plus estradiol treatment enhances learning and delay-dependent memory performance by young ovariectomized rats with partial loss of septal cholinergic neurons - Gibbs_2011_Horm.Behav_59_503
Author(s) : Gibbs RB , Chipman AM , Nelson D
Ref : Horm Behav , 59 :503 , 2011
Abstract : Effects of estrogen therapy on cognitive performance appear to diminish with age and time following the loss of ovarian function. We hypothesize that this is due to a reduction in basal forebrain cholinergic function and that treatment with a cholinergic enhancer can reverse the effect. This study tested whether combining the cholinesterase inhibitor donepezil with estradiol treatment can enhance/restore estradiol effects on cognitive performance in young ovariectomized rats with selective lesions of septal cholinergic neurons. 192IgG-saporin was injected directly into the medial septum to produce selective cholinergic lesions. Rats were then treated with donepezil (Don, daily injections of 3mg/kg/day, i.p.) or vehicle, and then with 17beta-estradiol (E2, administered by silastic capsule implanted s.c.) or an empty capsule. Rats were trained on a delayed matching-to-position (DMP) T-maze task which previous studies have shown is sensitive to ovariectomy and estrogen replacement. Results show that neither estradiol nor donepezil alone significantly enhanced acquisition of the DMP task in rats with cholinergic lesions. Combination therapy was effective, however, depending on the severity of the lesion. Don+E2 significantly enhanced acquisition of the task in rats with partial lesions (<50% loss of cholinergic neurons), but not in rats with severe lesions. This effect was due largely to a reduction in perseverative behavior. Don+E2 also improved working memory in rats with partial lesions, as evidenced by significantly better performance than controls during increased intertrial delays. These findings suggest that even partial loss of septal cholinergic neurons can reduce effects of estrogen therapy on cognitive performance, and demonstrate that combining a cholinesterase inhibitor with estrogen therapy can help to restore beneficial effects on performance. We propose that combination therapy may have similar beneficial effects in women, particularly in older women who have not used estrogen therapy for many years and are beginning to show signs of cognitive impairment or early Alzheimer's disease.
ESTHER : Gibbs_2011_Horm.Behav_59_503
PubMedSearch : Gibbs_2011_Horm.Behav_59_503
PubMedID: 21295576

Title : Donepezil treatment restores the ability of estradiol to enhance cognitive performance in aged rats: evidence for the cholinergic basis of the critical period hypothesis - Gibbs_2009_Horm.Behav_56_73
Author(s) : Gibbs RB , Mauk R , Nelson D , Johnson DA
Ref : Horm Behav , 56 :73 , 2009
Abstract : Recent studies suggest that the ability of estradiol to enhance cognitive performance diminishes with age and/or time following loss of ovarian function. We hypothesize that this is due, in part, to a decrease in basal forebrain cholinergic function. This study tested whether donepezil, a cholinesterase inhibitor, could restore estradiol effects on cognitive performance in aged rats that had been ovariectomized as young adults. Rats were ovariectomized at 3 months of age, and then trained on a delayed matching to position (DMP) T-maze task, followed by a configural association (CA) operant condition task, beginning at 12-17 or 22-27 months of age. Three weeks prior to testing, rats started to receive either donepezil or vehicle. After one week, half of each group also began receiving estradiol. Acclimation and testing began seven days later and treatment continued throughout testing. Estradiol alone significantly enhanced DMP acquisition in middle-aged rats, but not in aged rats. Donepezil alone had no effect on DMP acquisition in either age group; however, donepezil treatment restored the ability of estradiol to enhance DMP acquisition in aged rats. This effect was due largely to a reduction in the predisposition to adopt a persistent turn strategy during acquisition. These same treatments did not affect acquisition of the CA task in middle-aged rats, but did have small but significant effects on response time in aged rats. The data are consistent with the idea that estrogen effects on cognitive performance are task specific, and that deficits in basal forebrain cholinergic function are responsible for the loss of estradiol effect on DMP acquisition in aged ovariectomized rats. In addition, the data suggest that enhancing cholinergic function pharmacologically can restore the ability of estradiol to enhance acquisition of the DMP task in very old rats following long periods of hormone deprivation. Whether donepezil has similar restorative effects on other estrogen-sensitive tasks needs to be explored.
ESTHER : Gibbs_2009_Horm.Behav_56_73
PubMedSearch : Gibbs_2009_Horm.Behav_56_73
PubMedID: 19303882

Title : The genome of the model beetle and pest Tribolium castaneum - Richards_2008_Nature_452_949
Author(s) : Richards S , Gibbs RA , Weinstock GM , Brown SJ , Denell R , Beeman RW , Gibbs R , Bucher G , Friedrich M , Grimmelikhuijzen CJ , Klingler M , Lorenzen M , Roth S , Schroder R , Tautz D , Zdobnov EM , Muzny D , Attaway T , Bell S , Buhay CJ , Chandrabose MN , Chavez D , Clerk-Blankenburg KP , Cree A , Dao M , Davis C , Chacko J , Dinh H , Dugan-Rocha S , Fowler G , Garner TT , Garnes J , Gnirke A , Hawes A , Hernandez J , Hines S , Holder M , Hume J , Jhangiani SN , Joshi V , Khan ZM , Jackson L , Kovar C , Kowis A , Lee S , Lewis LR , Margolis J , Morgan M , Nazareth LV , Nguyen N , Okwuonu G , Parker D , Ruiz SJ , Santibanez J , Savard J , Scherer SE , Schneider B , Sodergren E , Vattahil S , Villasana D , White CS , Wright R , Park Y , Lord J , Oppert B , Brown S , Wang L , Weinstock G , Liu Y , Worley K , Elsik CG , Reese JT , Elhaik E , Landan G , Graur D , Arensburger P , Atkinson P , Beidler J , Demuth JP , Drury DW , Du YZ , Fujiwara H , Maselli V , Osanai M , Robertson HM , Tu Z , Wang JJ , Wang S , Song H , Zhang L , Werner D , Stanke M , Morgenstern B , Solovyev V , Kosarev P , Brown G , Chen HC , Ermolaeva O , Hlavina W , Kapustin Y , Kiryutin B , Kitts P , Maglott D , Pruitt K , Sapojnikov V , Souvorov A , Mackey AJ , Waterhouse RM , Wyder S , Kriventseva EV , Kadowaki T , Bork P , Aranda M , Bao R , Beermann A , Berns N , Bolognesi R , Bonneton F , Bopp D , Butts T , Chaumot A , Denell RE , Ferrier DE , Gordon CM , Jindra M , Lan Q , Lattorff HM , Laudet V , von Levetsow C , Liu Z , Lutz R , Lynch JA , da Fonseca RN , Posnien N , Reuter R , Schinko JB , Schmitt C , Schoppmeier M , Shippy TD , Simonnet F , Marques-Souza H , Tomoyasu Y , Trauner J , Van der Zee M , Vervoort M , Wittkopp N , Wimmer EA , Yang X , Jones AK , Sattelle DB , Ebert PR , Nelson D , Scott JG , Muthukrishnan S , Kramer KJ , Arakane Y , Zhu Q , Hogenkamp D , Dixit R , Jiang H , Zou Z , Marshall J , Elpidina E , Vinokurov K , Oppert C , Evans J , Lu Z , Zhao P , Sumathipala N , Altincicek B , Vilcinskas A , Williams M , Hultmark D , Hetru C , Hauser F , Cazzamali G , Williamson M , Li B , Tanaka Y , Predel R , Neupert S , Schachtner J , Verleyen P , Raible F , Walden KK , Angeli S , Foret S , Schuetz S , Maleszka R , Miller SC , Grossmann D
Ref : Nature , 452 :949 , 2008
Abstract : Tribolium castaneum is a member of the most species-rich eukaryotic order, a powerful model organism for the study of generalized insect development, and an important pest of stored agricultural products. We describe its genome sequence here. This omnivorous beetle has evolved the ability to interact with a diverse chemical environment, as shown by large expansions in odorant and gustatory receptors, as well as P450 and other detoxification enzymes. Development in Tribolium is more representative of other insects than is Drosophila, a fact reflected in gene content and function. For example, Tribolium has retained more ancestral genes involved in cell-cell communication than Drosophila, some being expressed in the growth zone crucial for axial elongation in short-germ development. Systemic RNA interference in T. castaneum functions differently from that in Caenorhabditis elegans, but nevertheless offers similar power for the elucidation of gene function and identification of targets for selective insect control.
ESTHER : Richards_2008_Nature_452_949
PubMedSearch : Richards_2008_Nature_452_949
PubMedID: 18362917
Gene_locus related to this paper: trica-ACHE1 , trica-ACHE2 , trica-d2a0g9 , trica-d2a0h0 , trica-d2a0w9 , trica-d2a0x0 , trica-d2a0x1 , trica-d2a0x3 , trica-d2a0x4.1 , trica-d2a0x4.2 , trica-d2a0x6 , trica-d2a2b8 , trica-d2a2h1 , trica-d2a3c3 , trica-d2a3g9 , trica-d2a5y5 , trica-d2a309 , trica-d2a514 , trica-d2a515 , trica-d2a516 , trica-d2a577 , trica-d2a578 , trica-d6w6x8 , trica-d6w7f9 , trica-d6w7h2 , trica-d6w8e7 , trica-d6w9c0 , trica-d6w855 , trica-d6wac8 , trica-d6wan4 , trica-d6wd50 , trica-d6wd73 , trica-d6wd74 , trica-A0A139WM97 , trica-d6wfu3 , trica-d6wgl2 , trica-d6wj57 , trica-d6wj59 , trica-d6wjs3 , trica-d6wl31 , trica-d6wnv1 , trica-d6wpl0 , trica-d6wqd6 , trica-d6wqr4 , trica-d6ws52 , trica-d6wsm0 , trica-d6wu38 , trica-d6wu39 , trica-d6wu40 , trica-d6wu41 , trica-d6wu44 , trica-d6wvk5 , trica-d6wvz7 , trica-d6wwu9 , trica-d6wwv0 , trica-d6wxz0 , trica-d6wyy1 , trica-d6wyy2 , trica-d6x0z2 , trica-d6x0z5 , trica-d6x0z6 , trica-d6x4b2 , trica-d6x4e8 , trica-d6x4e9 , trica-d6x197 , trica-d7eip7 , trica-d7eld3 , trica-d7us45 , trica-q5wm43 , trica-q5zex9 , trica-d6wie5 , trica-d6w7t0 , trica-d6x4h0 , trica-d6x4h1 , trica-a0a139wae8 , trica-a0a139wc96 , trica-d6x325 , trica-d2a4s2 , trica-d6wvw8

Title : The Fusarium graminearum genome reveals a link between localized polymorphism and pathogen specialization - Cuomo_2007_Science_317_1400
Author(s) : Cuomo CA , Guldener U , Xu JR , Trail F , Turgeon BG , Di Pietro A , Walton JD , Ma LJ , Baker SE , Rep M , Adam G , Antoniw J , Baldwin T , Calvo S , Chang YL , Decaprio D , Gale LR , Gnerre S , Goswami RS , Hammond-Kosack K , Harris LJ , Hilburn K , Kennell JC , Kroken S , Magnuson JK , Mannhaupt G , Mauceli E , Mewes HW , Mitterbauer R , Muehlbauer G , Munsterkotter M , Nelson D , O'Donnell K , Ouellet T , Qi W , Quesneville H , Roncero MI , Seong KY , Tetko IV , Urban M , Waalwijk C , Ward TJ , Yao J , Birren BW , Kistler HC
Ref : Science , 317 :1400 , 2007
Abstract : We sequenced and annotated the genome of the filamentous fungus Fusarium graminearum, a major pathogen of cultivated cereals. Very few repetitive sequences were detected, and the process of repeat-induced point mutation, in which duplicated sequences are subject to extensive mutation, may partially account for the reduced repeat content and apparent low number of paralogous (ancestrally duplicated) genes. A second strain of F. graminearum contained more than 10,000 single-nucleotide polymorphisms, which were frequently located near telomeres and within other discrete chromosomal segments. Many highly polymorphic regions contained sets of genes implicated in plant-fungus interactions and were unusually divergent, with higher rates of recombination. These regions of genome innovation may result from selection due to interactions of F. graminearum with its plant hosts.
ESTHER : Cuomo_2007_Science_317_1400
PubMedSearch : Cuomo_2007_Science_317_1400
PubMedID: 17823352
Gene_locus related to this paper: fusof-f9fxz4 , gibze-a8w610 , gibze-b1pdn0 , gibze-i1r9e6 , gibze-i1rda9 , gibze-i1rdk7 , gibze-i1rec8 , gibze-i1rgs0 , gibze-i1rgy0 , gibze-i1rh52 , gibze-i1rhi8 , gibze-i1rig9 , gibze-i1rip5 , gibze-i1rpg6 , gibze-i1rsg2 , gibze-i1rv36 , gibze-i1rxm5 , gibze-i1rxp8 , gibze-i1rxv5 , gibze-i1s1u3 , gibze-i1s3j9 , gibze-i1s6l7 , gibze-i1s8i8 , gibze-i1s9x4 , gibze-ppme1 , gibze-q4huy1 , gibze-i1rg17 , gibze-i1rb76 , gibze-i1s1m7 , gibze-i1s3z6 , gibze-i1rd78 , gibze-i1rgl9 , gibze-i1rjp7 , gibze-i1s1q6 , gibze-i1ri35 , gibze-i1rf76 , gibze-i1rhp3 , gibza-a0a016pda4 , gibza-a0a016pl96 , gibze-i1rjb5 , gibze-i1rkc4 , gibze-a0a1c3ylb1 , gibze-gra11 , gibze-fsl2

Title : The DNA sequence, annotation and analysis of human chromosome 3 - Muzny_2006_Nature_440_1194
Author(s) : Muzny DM , Scherer SE , Kaul R , Wang J , Yu J , Sudbrak R , Buhay CJ , Chen R , Cree A , Ding Y , Dugan-Rocha S , Gill R , Gunaratne P , Harris RA , Hawes AC , Hernandez J , Hodgson AV , Hume J , Jackson A , Khan ZM , Kovar-Smith C , Lewis LR , Lozado RJ , Metzker ML , Milosavljevic A , Miner GR , Morgan MB , Nazareth LV , Scott G , Sodergren E , Song XZ , Steffen D , Wei S , Wheeler DA , Wright MW , Worley KC , Yuan Y , Zhang Z , Adams CQ , Ansari-Lari MA , Ayele M , Brown MJ , Chen G , Chen Z , Clendenning J , Clerc-Blankenburg KP , Davis C , Delgado O , Dinh HH , Dong W , Draper H , Ernst S , Fu G , Gonzalez-Garay ML , Garcia DK , Gillett W , Gu J , Hao B , Haugen E , Havlak P , He X , Hennig S , Hu S , Huang W , Jackson LR , Jacob LS , Kelly SH , Kube M , Levy R , Li Z , Liu B , Liu J , Liu W , Lu J , Maheshwari M , Nguyen BV , Okwuonu GO , Palmeiri A , Pasternak S , Perez LM , Phelps KA , Plopper FJ , Qiang B , Raymond C , Rodriguez R , Saenphimmachak C , Santibanez J , Shen H , Shen Y , Subramanian S , Tabor PE , Verduzco D , Waldron L , Wang Q , Williams GA , Wong GK , Yao Z , Zhang J , Zhang X , Zhao G , Zhou J , Zhou Y , Nelson D , Lehrach H , Reinhardt R , Naylor SL , Yang H , Olson M , Weinstock G , Gibbs RA
Ref : Nature , 440 :1194 , 2006
Abstract : After the completion of a draft human genome sequence, the International Human Genome Sequencing Consortium has proceeded to finish and annotate each of the 24 chromosomes comprising the human genome. Here we describe the sequencing and analysis of human chromosome 3, one of the largest human chromosomes. Chromosome 3 comprises just four contigs, one of which currently represents the longest unbroken stretch of finished DNA sequence known so far. The chromosome is remarkable in having the lowest rate of segmental duplication in the genome. It also includes a chemokine receptor gene cluster as well as numerous loci involved in multiple human cancers such as the gene encoding FHIT, which contains the most common constitutive fragile site in the genome, FRA3B. Using genomic sequence from chimpanzee and rhesus macaque, we were able to characterize the breakpoints defining a large pericentric inversion that occurred some time after the split of Homininae from Ponginae, and propose an evolutionary history of the inversion.
ESTHER : Muzny_2006_Nature_440_1194
PubMedSearch : Muzny_2006_Nature_440_1194
PubMedID: 16641997
Gene_locus related to this paper: human-AADAC , human-AADACL2 , human-ABHD5 , human-ABHD6 , human-ABHD10 , human-ABHD14A , human-APEH , human-BCHE , human-CIB , human-LIPH , human-MGLL , human-NLGN1 , human-PLA1A

Title : Effects of long-term hormone replacement and of tibolone on choline acetyltransferase and acetylcholinesterase activities in the brains of ovariectomized, cynomologous monkeys - Gibbs_2002_Neurosci_113_907
Author(s) : Gibbs R , Nelson D , Anthony M , Clarkson T
Ref : Neuroscience , 113 :907 , 2002
Abstract : We examined long-term effects of low and high doses of tibolone, conjugated equine estrogens, and conjugated equine estrogens plus medroxyprogesterone acetate on choline acetyltransferase and acetylcholinesterase activities within different regions of the brain in cynomologus monkeys. All treatments were administered for 2 years. None of the treatments produced significant increases in either choline acetyltransferase or acetylcholinesterase in any of eight brain regions analyzed. In contrast, treatment with conjugated equine estrogens plus medroxyprogesterone acetate, but not conjugated equine estrogens alone, produced significant reductions in both choline acetyltransferase and acetylcholinesterase in the medial septum/diagonal band of Broca compared with untreated controls. Treatment with tibolone also resulted in significant reductions in both choline acetyltransferase and acetylcholinesterase in the medial septum/diagonal band of Broca, and this effect was dose-related. These findings are the first to report the effects of long-term therapies used by postmenopausal women on cholinergic measures in the primate brain. The findings are consistent with recent reports in rats, and suggest that any positive effects of long-term estrogen or hormone replacement therapy on cognitive processes are probably not due to significant effects on choline acetyltransferase or acetylcholinesterase activities.
ESTHER : Gibbs_2002_Neurosci_113_907
PubMedSearch : Gibbs_2002_Neurosci_113_907
PubMedID: 12182896

Title : Prolyl tripeptidyl peptidase from Porphyromonas gingivalis. A novel enzyme with possible pathological implications for the development of periodontitis - Banbula_1999_J.Biol.Chem_274_9246
Author(s) : Banbula A , Mak P , Bugno M , Silberring J , Dubin A , Nelson D , Travis J , Potempa J
Ref : Journal of Biological Chemistry , 274 :9246 , 1999
Abstract : Porphyromonas gingivalis possesses a complex proteolytic system, which is essential for both its growth and evasion of host defense mechanisms. In this report we characterized, both at a protein and genomic level, a novel peptidase of this system with prolyl tripeptidyl peptidase activity. The enzyme was purified to homogeneity, and its enzymatic activity and biochemical properties were investigated. The amino acid sequence at the amino terminus and of internal peptide fragments enabled identification of the gene encoding this enzyme, which we refer to as PtpA for prolyl tripeptidyl peptidase A. The gene encodes an 82-kDa protein, which contains a GWSYGG motif, characteristic for members of the S9 prolyl oligopeptidase family of serine proteases. However, it does not share any structural similarity to other tripeptidyl peptidases, which belong to the subtilisin family. The production of prolyl tripeptidyl peptidase may contribute to the pathogenesis of periodontal tissue destruction through the mutual interaction of this enzyme, host and bacterial collagenases, and dipeptidyl peptidases in the degradation of collagen during the course of infection.
ESTHER : Banbula_1999_J.Biol.Chem_274_9246
PubMedSearch : Banbula_1999_J.Biol.Chem_274_9246
PubMedID: 10092598