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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Amphetamine Locomotor Sensitization and Conditioned Place Preference in Adolescent Male and Female Rats Neonatally Treated with Quinpirole

Brown, Russell W., Perna, Marla K., Noel, Daniel M., Whittemore, Jamie D., Lehmann, Julia, Smith, Meredith L. 01 August 2010 (has links)
Neonatal quinpirole treatment has been shown to produce an increase in dopamine D2-like receptor sensitivity that persists throughout the subject's lifetime. The objective was to analyze the effects of neonatal quinpirole treatment on effects of amphetamine in adolescent rats using locomotor sensitization and conditioned place preference procedures. Sprague-Dawley rats were treated with quinpirole (1 mg/kg) or saline from postnatal days (P)1 to P11 and raised to adolescence. For locomotor sensitization, subjects were given amphetamine (1 mg/kg) or saline every second day from P35 to P47 and were placed into a locomotor arena. In female rats, neonatal quinpirole treatment enhanced amphetamine locomotor sensitization compared with quinpirole-free controls sensitized to amphetamine. Male rats demonstrated sensitization to amphetamine, although this was muted compared with female rats, and were unaffected by neonatal quinpirole. For conditioned place preference, subjects were conditioned for 8 consecutive days (P32-39) with amphetamine (1 mg/kg) or saline and a drug-free preference test was conducted at P40. Rats treated with neonatal quinpirole enhanced time spent in the amphetamine-paired context compared with quinpirole-free controls conditioned with amphetamine, but only female controls conditioned with amphetamine spent more time in the drug-paired context compared with saline-treated controls. Increased D₂-like receptor sensitivity appears to have enhanced the behavioral effects of amphetamine, but these effects were more prevalent in adolescent female rats compared with male rats.
12

Neonatal Methamphetamine Administration Induces Region-Specific Long-Term Neuronal Morphological Changes in the Rat Hippocampus, Nucleus Accumbens and Parietal Cortex

Williams, Michael T., Brown, Russell W., Vorhees, Charles V. 01 June 2004 (has links)
Previous studies have demonstrated that rats exposed to methamphetamine (MA) during the neonatal period display deficits in spatial learning and memory. The underlying correlates are; therefore, this study was devised to determine whether neuronal changes occur in the dentate gyrus (DG), nucleus accumbens (NAcc) and cortex of adult rats exposed to 10 mg/kg MA administered four times daily from P11-20 using Golgi-Cox staining [Gibb, R. & Kolb, B. (1998) J. Neurosci. Meth., 79, 1-4]. The DG and NAcc demonstrated a decrease in the number of spines per neuron and the NAcc showed an associated decrease in dendritic length. Selective changes in cortex were observed because increased dendritic length in the parietal cortex occurred with no change in the number of spines, and no differences were noted for either dendritic length or spines in the medial frontal cortex. The data suggest a potential cause for the learning and memory deficits induced by neonatal MA exposure; however, the underlying mechanism that produces these neuronal changes is.
13

Alterações neurocognitivas e morfométricas cerebrais associadas ao uso do crack / Neurocognitive and morphometric brain alterations associated with crack use

Oliveira Junior, Hercilio Pereira de 06 June 2018 (has links)
INTRODUÇAO: Recentes achados experimentais sugerem que a cocaína na forma crack é mais neurotóxica quando comparada à cocaína inalada. Estes estudos são congruentes com os achados clínicos de que pacientes com transtorno por uso da cocaína e usuários de crack têm pior prognóstico e mais consequências adversas para à saúde. OBJETIVO: Investigar alterações diferenciais em substância cinzenta cerebral (SC) e prejuízos neurocognitivos entre usuários de crack (CRACK), cocaína inalada (COC) e controles. MÉTODOS: 78 indivíduos adultos foram avaliados neste estudo (16 CRACK, 26 COC e 36 controles). Todos indivíduos realizaram uma bateria abrangente de testes neurocognitivos. Dados estruturais do cérebro foram analisados através de um protocolo de morfometria baseada em voxels (VBM) e do Statistical Parametric Mapping (SPM) 12. Diferenças em volume de substância cinzenta entre os três grupos foram avaliadas através de um modelo fatorial tendo idade e escolaridade como covariáveis. Foram realizados testes de correlação entre variáveis de uso da cocaína e volume de substância cinzenta. RESULTADOS: Participantes do grupo CRACK apresentaram volumes menores de SC no córtex orbitofrontal esquerdo (p < 0,001), cingulado anterior bilateral (p < 0,001), córtex precentral direito e córtex temporal medial (p < 0,05) em relação aos controles. Em comparação aos indivíduos do grupo COC, os indivíduos do grupo CRACK tiveram volumes menores de SC no córtex orbitofrontal esquerdo (p < 0,001), cingulado anterior direito (p < 0,05) e giro parietal superior esquerdo (p < 0,001). A idade de início de uso da cocaína mais precoce foi associada a volumes menores de SC no córtex temporal superior esquerdo (p < 0,05) e lóbulo paracentral direito (p < 0,05) no grupo total de usuários e CRACK. Anos de uso da cocaína foram associados negativamente ao volume de SC no polo temporal medial direito (p < 0,05) no grupo CRACK. O uso da droga no último mês foi associado a volumes menores de SC em córtex parahipocampal e hipocampo direito (p < 0,05) no grupo total de usuários e CRACK e cíngulo anterior direito apenas no grupo CRACK (p < 0,05). CRACK e COC desempenharam pior que os controles em funções executivas globais e impulsividade. CONCLUSÕES: Nossos resultados sugerem que usuários de crack apresentam alterações mais graves em região pré-frontal e prejuízos em funções cognitivas como auto-monitorização e funções executivas quando comparados a usuários de cocaína inalada. Variáveis como idade de início da cocaína, anos de uso e dias de uso da droga no último mês foram associadas a volumes menores de SC em regiões corticais relacionadas ao funcionamento executivo e controle inibitório. Em conclusão, usuários de crack apresentaram mais prejuízos em região pré-frontal do cérebro e novos estudos longitudinais poderão contribuir para uma melhor compreensão de como tais alterações podem impactar negativamente o curso clínico e resultados no tratamento / BACKGROUND: Recent experimental studies have shown that smoked crack is more neurotoxic when compared with intranasal cocaine. These reports are congruent with clinical findings that crack-addicted patients have a worse prognosis and more severe health consequences. AIM: To examine differential gray matter (GM) alterations and neurocognitive impairments in crack-addicted patients (CRACK) compared with intrasanal cocaine-addicted patients (COC) and controls. METHODS: 78 adult male subjects were evaluated in this study (16 CRACK, 26 COC and 36 controls). Subjects were submitted to an extensive battery of neurocognitive tests. Structural brain data were analyzed using a voxel-based morphometry (VBM) protocol and the Statistical Parametric Mapping (SPM) 12. Differences in gray matter volume among the three groups were investigated with a full-factorial model controlling for age and years of education. We have performed a correlation analysis between variables of cocaine use and gray matter volume. RESULTS: CRACK presented significantly reduced GM volume in left orbitofrontal (p < .001), bilateral anterior cingulate (p < .001), right precentral gyrus (p < .05), and right medial temporal cortex (p < .05) compared with controls. When directly compared with COC, CRACK had reduced GM volume in left orbitofrontal (p < .001), right anterior cingulate (p < .05), and left superior parietal gyrus (p < .001). Age at first cocaine use was positively associated with GM volume in the left superior temporal cortex (p < .05) and paracentral lobe (p < .05) in the total sample and CRACK. Years of cocaine use were negatively associated with GM volume in the right medial temporal pole (p < .05) in CRACK. Past-30 days cocaine use was associated with reduced GM in the parahippocampal and hippocampus (p < .05) in the total sample and reduced right anterior cingulus in CRACK (p < .05). Both CRACK and COC participants performed worse than controls in global measures of executive functioning and impulsivity. CONCLUSION: Our results suggest that participants with cocaine use disorder who use crack present more severe prefrontal cortex abnormalities and self-monitoring/executive alterations when compared with intrasanal cocaine users. Age of first cocaine use, years of cocaine exposure, and past-30 days cocaine use were associated with GM reductions in cortical areas implicated in executive functioning and inhibitory control. In conclusion, crack users presented more alterations in the prefrontal cortex and further longitudinal studies are warranted to a better comprehension of how such alterations may impact negatively treatment outcomes
14

The role of adenosine and its receptor subtypes in nociception and neuropathic pain /

Wu, Weiping, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.
15

Alterações neurocognitivas e morfométricas cerebrais associadas ao uso do crack / Neurocognitive and morphometric brain alterations associated with crack use

Hercilio Pereira de Oliveira Junior 06 June 2018 (has links)
INTRODUÇAO: Recentes achados experimentais sugerem que a cocaína na forma crack é mais neurotóxica quando comparada à cocaína inalada. Estes estudos são congruentes com os achados clínicos de que pacientes com transtorno por uso da cocaína e usuários de crack têm pior prognóstico e mais consequências adversas para à saúde. OBJETIVO: Investigar alterações diferenciais em substância cinzenta cerebral (SC) e prejuízos neurocognitivos entre usuários de crack (CRACK), cocaína inalada (COC) e controles. MÉTODOS: 78 indivíduos adultos foram avaliados neste estudo (16 CRACK, 26 COC e 36 controles). Todos indivíduos realizaram uma bateria abrangente de testes neurocognitivos. Dados estruturais do cérebro foram analisados através de um protocolo de morfometria baseada em voxels (VBM) e do Statistical Parametric Mapping (SPM) 12. Diferenças em volume de substância cinzenta entre os três grupos foram avaliadas através de um modelo fatorial tendo idade e escolaridade como covariáveis. Foram realizados testes de correlação entre variáveis de uso da cocaína e volume de substância cinzenta. RESULTADOS: Participantes do grupo CRACK apresentaram volumes menores de SC no córtex orbitofrontal esquerdo (p < 0,001), cingulado anterior bilateral (p < 0,001), córtex precentral direito e córtex temporal medial (p < 0,05) em relação aos controles. Em comparação aos indivíduos do grupo COC, os indivíduos do grupo CRACK tiveram volumes menores de SC no córtex orbitofrontal esquerdo (p < 0,001), cingulado anterior direito (p < 0,05) e giro parietal superior esquerdo (p < 0,001). A idade de início de uso da cocaína mais precoce foi associada a volumes menores de SC no córtex temporal superior esquerdo (p < 0,05) e lóbulo paracentral direito (p < 0,05) no grupo total de usuários e CRACK. Anos de uso da cocaína foram associados negativamente ao volume de SC no polo temporal medial direito (p < 0,05) no grupo CRACK. O uso da droga no último mês foi associado a volumes menores de SC em córtex parahipocampal e hipocampo direito (p < 0,05) no grupo total de usuários e CRACK e cíngulo anterior direito apenas no grupo CRACK (p < 0,05). CRACK e COC desempenharam pior que os controles em funções executivas globais e impulsividade. CONCLUSÕES: Nossos resultados sugerem que usuários de crack apresentam alterações mais graves em região pré-frontal e prejuízos em funções cognitivas como auto-monitorização e funções executivas quando comparados a usuários de cocaína inalada. Variáveis como idade de início da cocaína, anos de uso e dias de uso da droga no último mês foram associadas a volumes menores de SC em regiões corticais relacionadas ao funcionamento executivo e controle inibitório. Em conclusão, usuários de crack apresentaram mais prejuízos em região pré-frontal do cérebro e novos estudos longitudinais poderão contribuir para uma melhor compreensão de como tais alterações podem impactar negativamente o curso clínico e resultados no tratamento / BACKGROUND: Recent experimental studies have shown that smoked crack is more neurotoxic when compared with intranasal cocaine. These reports are congruent with clinical findings that crack-addicted patients have a worse prognosis and more severe health consequences. AIM: To examine differential gray matter (GM) alterations and neurocognitive impairments in crack-addicted patients (CRACK) compared with intrasanal cocaine-addicted patients (COC) and controls. METHODS: 78 adult male subjects were evaluated in this study (16 CRACK, 26 COC and 36 controls). Subjects were submitted to an extensive battery of neurocognitive tests. Structural brain data were analyzed using a voxel-based morphometry (VBM) protocol and the Statistical Parametric Mapping (SPM) 12. Differences in gray matter volume among the three groups were investigated with a full-factorial model controlling for age and years of education. We have performed a correlation analysis between variables of cocaine use and gray matter volume. RESULTS: CRACK presented significantly reduced GM volume in left orbitofrontal (p < .001), bilateral anterior cingulate (p < .001), right precentral gyrus (p < .05), and right medial temporal cortex (p < .05) compared with controls. When directly compared with COC, CRACK had reduced GM volume in left orbitofrontal (p < .001), right anterior cingulate (p < .05), and left superior parietal gyrus (p < .001). Age at first cocaine use was positively associated with GM volume in the left superior temporal cortex (p < .05) and paracentral lobe (p < .05) in the total sample and CRACK. Years of cocaine use were negatively associated with GM volume in the right medial temporal pole (p < .05) in CRACK. Past-30 days cocaine use was associated with reduced GM in the parahippocampal and hippocampus (p < .05) in the total sample and reduced right anterior cingulus in CRACK (p < .05). Both CRACK and COC participants performed worse than controls in global measures of executive functioning and impulsivity. CONCLUSION: Our results suggest that participants with cocaine use disorder who use crack present more severe prefrontal cortex abnormalities and self-monitoring/executive alterations when compared with intrasanal cocaine users. Age of first cocaine use, years of cocaine exposure, and past-30 days cocaine use were associated with GM reductions in cortical areas implicated in executive functioning and inhibitory control. In conclusion, crack users presented more alterations in the prefrontal cortex and further longitudinal studies are warranted to a better comprehension of how such alterations may impact negatively treatment outcomes
16

Fentanyl and Other Opioid Involvement in Methamphetamine-Related Deaths

Dai, Zheng, Abate, Marie A., Groth, Caroline P., Rucker, Tori, Kraner, James C., Mock, Allen R., Smith, Gordon S. 04 March 2022 (has links)
: Methamphetamine-related deaths have been rising along with those involving synthetic opioids, mostly fentanyl and fentanyl analogs (FAs). However, the extent to which methamphetamine involvement in deaths differs from those changes occurring in synthetic opioid involvement is unknown.: To determine the patterns and temporal changes in methamphetamine-related deaths with and without other drug involvement.: Data from all methamphetamine-related deaths in West Virginia from 2013 to 2018 were analyzed. Quasi-Poisson regression analyses over time were conducted to compare the rates of change in death counts among methamphetamine and fentanyl//FA subgroups.: A total of 815 methamphetamine-related deaths were analyzed; 572 (70.2%) were male and 527 (64.7%) involved an opioid. The proportion of methamphetamine only deaths stayed relatively flat over time although the actual numbers of deaths increased. Combined fentanyl/FAs and methamphetamine were involved in 337 deaths (41.3%) and constituted the largest increase from 2013 to 2018. The modeling of monthly death counts in 2017-2018 found that the average number of deaths involving fentanyl without methamphetamine significantly declined (rate of change -0.025, < .001), while concomitant fentanyl with methamphetamine and methamphetamine only death counts increased significantly (rate of change 0.056 and 0.057, respectively, < .001).: Fentanyl and FAs played an increasingly significant role in methamphetamine-related deaths. The accelerating number of deaths involving fentanyl/FAs and methamphetamine indicates the importance of stimulants and opioids in unintentional deaths. Comprehensive surveillance efforts should continue to track substance use patterns to ensure that appropriate prevention programs are undertaken.
17

A Role for Histone Modification in the Mechanism of Action of Antidepressant and Stimulant Drugs: a Dissertation

Schroeder, Frederick Albert 28 December 2007 (has links)
Depression and stimulant drug addiction each result in massive losses of health, productivity and human lives every year. Despite decades of research, current treatment regimes for depression are ineffective in approximately half of all patients. Therapy available to stimulant drug addicts is largely ineffective and moreover, dedicated treatments for drug dependence (including abuse of cocaine) are non-existent. Thus, there is a pressing need to further understanding of the molecular mechanisms underlying these disorders in order to develop novel, targeted therapeutic strategies. Chromatin remodeling, including changes in histone acetylation, has been proposed to play a role in both the etiology and treatment of depression and stimulant abuse. Histone acetyltransferases (HATs) and histone deacetylases (HDACs) regulate numerous cellular processes, including transcription, cell cycle progression and differentiation. Moreover, histone acetylation has been shown to regulate hippocampal neurogenesis, a cellular response associated with the pathogenesis and treatment of depression and stimulant abuse (Hsieh et al., 2004, Yamaguchi et al., 2004, Fischer et al., 2007). Ultimately, such basic cellular processes impact higher order function, namely cognition and emotion. Indeed, recent studies suggest that HDAC activity in selected forebrain regions, including ventral striatum and hippocampus, modulate stimulant- and antidepressantinduced behavior (Kumar et al., 2005, Tsankova et al., 2006a, Fischer et al., 2007). These reports highlight an association between chromatin remodeling and diverse behavioral changes, including changes induced by the pleiotropic HDAC inhibitor, sodium butyrate (SB), (Kumar et al., 2005, Tsankova et al., 2006a, Fischer et al., 2007). However, behavioral, brain-metabolic and molecular effects of SB treatment in the context of rodent models of depression, dopaminergic sensitization and repeated cocaine administration remained unclear. The work described in this thesis illustrates the potential for chromatin modifying drugs in mechanisms underlying the experimental pharmacology of depression and stimulant addiction. Specifically, the data presented here support the view that treatment with the short chain fatty acid, sodium butyrate enhances: (1) antidepressant-like behavioral effects of the selective serotonin reuptake inhibitor (SSRI), fluoxetine (2) locomotor sensitization induced by repeated administration of the dopamine D1/D5 receptor agonist SKF82958; and(3) brain metabolic activation upon repeated cocaine administration as evidenced by fMRI in awake rats. Furthermore, this report provides evidence that these treatment paradigms will result in chromatin modification changes associated with active transcription, in addition to increased mRNA levels of plasticity-associated genes, including brain-derived neurotrophic factor (BDNF) at key brain regions implicated in the pathogenesis of depression and stimulant addiction. To date, little is known regarding the underlying mechanisms of action mediating the enhancing effects of sodium butyrate on the various antidepressant- and stimulantrelated paradigms. Our findings underscore the potential of chromatin-modifying drugs to profoundly affect the behavioral response of an animal to antidepressant and stimulant drugs and warrants consideration in the context of developing novel therapeutic strategies.

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