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Search Results: 1 - 10 of 226456 matches for " Nancy R. Zahniser "
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Differences in Rat Dorsal Striatal NMDA and AMPA Receptors following Acute and Repeated Cocaine-Induced Locomotor Activation
Dorothy J. Yamamoto, Nancy R. Zahniser
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0037673
Abstract: Sprague-Dawley rats can be classified as low or high cocaine responders (LCRs or HCRs, respectively) based on their locomotor activity induced by an acute low dose of cocaine. Upon repeated cocaine exposure, LCRs display greater locomotor sensitization, reward, and reinforcement than HCRs. Altered glutamate receptor expression in the brain reward pathway has been linked to locomotor sensitization and addiction. To determine if such changes contribute to the differential development of locomotor sensitization, we examined protein levels of total, phosphorylated, and cell surface glutamate N-methyl D-aspartate (NMDA) and α-amino-3-hydroxy-5-methylisoxazole-4-pr?opionate(AMPA) receptors (Rs) following acute or repeated cocaine (10 mg/kg, i.p.) in LCRs, HCRs and saline controls. Three areas involved in the development and expression of locomotor sensitization were investigated: the ventral tegmental area (VTA), nucleus accumbens (NAc) and dorsal striatum (dSTR). Our results revealed differences only in the dSTR, where we found that after acute cocaine, GluN2BTyr-1472 phosphorylation was significantly greater in LCRs, compared to HCRs and controls. Additionally in dSTR, after repeated cocaine, we observed significant increases in total GluA1, phosphorylated GluA1Ser-845, and cell surface GluA1 in all cocaine-treated animals vs. controls. The acute cocaine-induced increases in NMDARs in dSTR of LCRs may help to explain the more ready development of locomotor sensitization and susceptibility to addiction-like behaviors in rats that initially exhibit little or no cocaine-induced activation, whereas the AMPAR increases after repeated cocaine may relate to recruitment of more dorsal striatal circuits and maintenance of the marked cocaine-induced locomotor activation observed in all of the rats.
A Relationship between Reduced Nucleus Accumbens Shell and Enhanced Lateral Hypothalamic Orexin Neuronal Activation in Long-Term Fructose Bingeing Behavior
Jacki M. Rorabaugh, Jennifer M. Stratford, Nancy R. Zahniser
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0095019
Abstract: Fructose accounts for 10% of daily calories in the American diet. Fructose, but not glucose, given intracerebroventricularly stimulates homeostatic feeding mechanisms within the hypothalamus; however, little is known about how fructose affects hedonic feeding centers. Repeated ingestion of sucrose, a disaccharide of fructose and glucose, increases neuronal activity in hedonic centers, the nucleus accumbens (NAc) shell and core, but not the hypothalamus. Rats given glucose in the intermittent access model (IAM) display signatures of hedonic feeding including bingeing and altered DA receptor (R) numbers within the NAc. Here we examined whether substituting fructose for glucose in this IAM produces bingeing behavior, alters DA Rs and activates hedonic and homeostatic feeding centers. Following long-term (21-day) exposure to the IAM, rats given 8–12% fructose solutions displayed fructose bingeing but unaltered DA D1R or D2R number. Fructose bingeing rats, as compared to chow bingeing controls, exhibited reduced NAc shell neuron activation, as determined by c-Fos-immunoreactivity (Fos-IR). This activation was negatively correlated with orexin (Orx) neuron activation in the lateral hypothalamus/perifornical area (LH/PeF), a brain region linking homeostatic to hedonic feeding centers. Following short-term (2-day) access to the IAM, rats exhibited bingeing but unchanged Fos-IR, suggesting only long-term fructose bingeing increases Orx release. In long-term fructose bingeing rats, pretreatment with the Ox1R antagonist SB-334867 (30 mg/kg; i.p.) equally reduced fructose bingeing and chow intake, resulting in a 50% reduction in calories. Similarly, in control rats, SB-334867 reduced chow/caloric intake by 60%. Thus, in the IAM, Ox1Rs appear to regulate feeding based on caloric content rather than palatability. Overall, our results, in combination with the literature, suggest individual monosaccharides activate distinct neuronal circuits to promote feeding behavior. Specifically, long-term fructose bingeing activates a hyperphagic circuit composed in part of NAc shell and LH/PeF Orx neurons.
Neurotransplantation of stem cells genetically modified to express human dopamine transporter reduces alcohol consumption
Tom N Grammatopoulos, Susan M Jones, Masami Yoshimura, Brian R Hoover, Mita Das, Evan Y Snyder, Gaynor A Larson, Nancy R Zahniser, Boris Tabakoff, W Michael Zawada
Stem Cell Research & Therapy , 2010, DOI: 10.1186/scrt36
Abstract: We have generated a neural stem cell line stably expressing the hDAT. Uptake kinetics of DA were determined to select a clone for transplantation. These genetically modified stem cells (or cells transfected with a construct lacking the hDAT sequence) were transplanted bilaterally into the NAC of wild-type mice trained to consume 10% alcohol in a two-bottle free-choice test for alcohol consumption. Alcohol intake was then ascertained for 1 week after transplantation, and brain sections through the NAC were examined for surviving grafted cells.Modified stem cells expressed hDAT and uptaken DA selectively via hDAT. Mice accustomed to drinking 10% ethanol by free choice reduced their alcohol consumption after being transplanted with hDAT-expressing stem cells. By contrast, control stem cells lacked that effect. Histologic examination revealed surviving stem cells in the NAC of all engrafted brains.Our findings represent proof of principle suggesting that genetically engineered stem cells can be useful for exploring the role of neurotransmitters (or other signaling molecules) in alcohol consumption and potentially in other aspects of brain function.It has been 50 years since Olds and Milner [1] described the existence of reward pathways in the brain, based on their experiments showing that electrical stimulation of certain brain areas is rewarding to rats. Today's understanding of common reward pathways in the brain involves the mesocorticolimbic circuitry consisting of dopaminergic cell bodies in the ventral tegmental area (VTA) and their projections to terminal areas of the prefrontal cortex and the "extended amygdala" (the NAC, substantia innominata, bed nucleus of the stria terminalis and amygdala). Rewarding stimuli such as food, sex, and drugs of abuse, including ethanol, result in the release of DA in terminal areas, particularly the NAC [2]. Although the dopaminergic mesocorticolimbic pathway is clearly involved in reward mechanisms, questions about the precise r
Policy on reintegration of women with histories of substance abuse: A mixed methods study of predictors of relapse and facilitators of recovery
Nancy R VanDeMark
Substance Abuse Treatment, Prevention, and Policy , 2007, DOI: 10.1186/1747-597x-2-28
Abstract: The present cross-sectional study examined the predictors of relapse and the facilitators of recovery in a sample of 325 women with histories of substance abuse. Analysis of secondary data, collected as part of a national cross-site study, employed a mixed methods approach conducting (1) logistic regression to examine the predictors of relapse and (2) an inductive qualitative analysis of responses from open-ended items to explore the women's perceptions of barriers to and facilitators of recovery.Results suggest that lower levels of instrumental support, affective support, and participation in normal roles (such as parent, employee, student, and citizen) are significant predictors of relapse to drug use and criminal behaviors. Qualitative findings support the quantitative results, revealing that participating women perceived the variables of support and role participation as critical in facilitating their recovery. They also noted the importance of individual characteristics such as optimism and strength and emphasized the significance of their relationship with their children in motivating them to avoid relapse. Findings suggest that punitive policies toward women with substance abuse histories may be ineffective.The author concludes that current policies designed to withhold access to basic needs such as housing, education, cash assistance, and positive relationships may deprive women with histories of substance abuse of the means to reconnect with society. Policies that promote access to basic needs and offer avenues for women to participate in normal societal roles should be more fully explored.Substance abuse is a social problem of great importance to contemporary American society. According to the National Survey on Drug Use and Health, it is estimated that 22.5 million people, or 9.4% of the U.S. population, experience problems with substance abuse [1]. Substance abuse places a considerable burden on society: Hundreds of billions of dollars are spent each yea
Línea de base del proyecto de salud sexual y reproductiva para adolescentes en Medellín: componente cualitativo
Gallo R,Nancy E;
Revista Facultad Nacional de Salud Pública , 2009,
Abstract: objective: to approach the perception of adolescents and adults opinion makers on teenage pregnancy, sexual and reproductive health (srh), use of birth control (bc) and use of srh services. methodology: a descriptive study ethnographic with focused interviews and semi-structured guide. the convenience sample consisted of 80 young people (men and women) between 14 and 19 years old and 6 adult women opinion makers. eight focus groups were conducted with youth and six interviews. results: in intergenerational encounters are explanatory reasons on teenage pregnancy in the city of medellin the construction of the process of trust-distrust in the conquest and the adolescent partner life affects the use of bc, including the condom. the main barrier to adolescents? access to srh services is the lack of credibility in them. conclusions: the break with the ideal of the adult world, the ideas they have about love, relationships, cultural precepts that designate the gender behavior and credibility they have about srh services are fields of analysis that are directly linked to the issue of teenage pregnancy in the city of medellin.
Baseline of the sexual and reproductive health project for adolescents in Medellín: the qualitative component
Nancy E. Gallo R
Revista Facultad Nacional de Salud Pública , 2009,
Abstract: Objective: To approach the perception of adolescents and adults opinion makers on teenage pregnancy, sexual and reproductive health (s r h), use of birth control (b c) and use of s r h services. Methodology: a descriptive study ethnographic with focused interviews and semi-structured guide. The convenience sample consisted of 80 young people (men and women) between 14 and 19 years old and 6 adult women opinion makers. Eight focus groups were conducted with youth and six interviews. Results:in intergenerational encounters are explanatory reasons on teenage pregnancy in the city of Medellin The construction of the process of trust-distrust in the conquest and the adolescent partner life affects the use of b c, including the condom. The main barrier to adolescents’ access to s r h services is the lack of credibility in them. Conclusions: The break with the ideal of the adult world, the ideas they have about love, relationships, cultural precepts that designate the gender behavior and credibility they have about s r h services are fields of analysis that are directly linked to the issue of teenage pregnancy in the city of Medellin.
A review of the tribes of Deltocephalinae (Hemiptera: Auchenorrhyncha: Cicadellidae)
James N. Zahniser,Chris Dietrich
European Journal of Taxonomy , 2013, DOI: 10.5852/ejt.2013.45
Abstract: The classification of the largest subfamily of leafhoppers, Deltocephalinae, including 38 tribes, 923 genera, and 6683 valid species, is reviewed and revised. An updated phylogeny of the subfamily based on molecular (28S, Histone H3) and morphological data and an expanded taxon sample (37 taxa not included in previous analyses) is presented. Based on the results of these analyses and on the morphological examination of many representatives of the subfamily, the classification of the tribes and subtribes of Deltocephalinae is revised. Complete morphological descriptions, illustrations, lists of the included genera, and notes on their distribution, ecology, and important vector species are provided for the 38 recognized tribes and 18 subtribes. A dichotomous key to the tribes is provided. All names in the taxonomic treatments are hyperlinked to online resources for individual taxa which are supported by a comprehensive database for Deltocephalinae compiled using the taxonomic database software package 3I. The online functionality includes an interactive key to tribes and subtribes and advanced database searching options. Each taxon (subspecies through subfamily) has a unique taxon webpage providing nomenclatural information, lists of included taxa, an automated description (if available), images (if available), distributional information, bibliographic references and links to outside resources. Some observations and trends regarding the history of taxonomic descriptions in Deltocephalinae are reported. Four new tribes are described: Bahitini tribe nov. (25 genera), Bonsapeiini tribe nov. (21 genera), Phlepsiini tribe nov. (4 genera), and Vartini tribe nov. (7 genera). The circumscription and morphological characterization of Scaphoideini Oman, 1943 (61 genera) is substantially revised. Eleven new species are described: Acostemma stilleri sp. nov., Arrugada linnavuorii sp. nov., Drabescus zhangi sp. nov., Parabolopona webbi sp. nov., Goniagnathus emeljanovi sp. nov., Hecalus hamiltoni sp. nov., Scaphoideus omani sp. nov., Dwightla delongi sp. nov., Abimwa knighti sp. nov., Gannia viraktamathi sp. nov., and Doratulina dmitrievi sp. nov. Some family-group level taxonomic changes are made: Platymetopiini Haupt, 1929, Anoterostemmini Haupt, 1929, and Allygidiina Dmitriev, 2006 are synonymized with Athysanini Van Duzee, 1892, syn. nov.; Procepitini Dmitriev, 2002 is synonymized with Cicadulini Van Duzee, 1892, syn. nov.; Listrophorini Boulard, 1971 is synonymized with Chiasmini Distant, 1908, syn. nov.; Adamini Linnavuori & Al-Ne’amy, 1983, Dwightlini McKamey,
Ethical and Scientific Considerations Regarding Animal Testing and Research
Hope R. Ferdowsian, Nancy Beck
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0024059
Abstract:
Impaired Thymic Selection and Abnormal Antigen-Specific T Cell Responses in Foxn1Δ/Δ Mutant Mice
Shiyun Xiao,Nancy R. Manley
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0015396
Abstract: Foxn1Δ/Δ mutant mice have a specific defect in thymic development, characterized by a block in TEC differentiation at an intermediate progenitor stage, and blocks in thymocyte development at both the DN1 and DP cell stages, resulting in the production of abnormally functioning T cells that develop from an atypical progenitor population. In the current study, we tested the effects of these defects on thymic selection.
Restricciones en el canal de comunicación y representación de influencia en situación de toma de decisión
Vivas, Jorge R.;Terroni, Nancy;
Psico-USF , 2001, DOI: 10.1590/S1413-82712001000100004
Abstract: computer mediated communication had a high social impact in the last decade. the psychosocial effects of the use of these technological media on human communication are observed with growing interest. this work reports the differences of influence perception during the collaborative making decision task when varying the communicational channel restrictions (face to face or computer mediated). the design included a hundred students in both task conditions on a multiple decision problem. the outcomes show a great differences in how individuals remarks different aspects for the representational construction of the influence in each modality. these results suggest that the amount of social presence is modulated by the channel restrictions, which make it difficult and even constrain, the perception of the social mechanisms of influence that allow the adjusted influence of a representational construction to the real interchanges around the group product goal.
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