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1.
Appetite ; 199: 107389, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38697221

RESUMO

The complications of obesity extend beyond the periphery to the central nervous system (CNS) and include an increased risk of developing neuropsychiatric co-morbidities like depressive illness. Preclinical studies support this concept, including studies that have examined the effects of a high-fat diet (HFD) on depressive-like behaviors. Although women are approximately two-fold more likely to develop depressive illness compared to men, most preclinical studies have focused on the effects of HFD in male rodents. Accordingly, the goal of this study was to examine depressive-like behaviors in male and female rats provided access to a HFD. In agreement with prior studies, male and female rats provided a HFD segregate into an obesity phenotype (i.e., diet-induced obesity; DIO) or a diet resistant (DR) phenotype. Upon confirmation of the DR and DIO phenotypes, behavioral assays were performed in control chow, DR, and DIO rats. In the sucrose preference test, male DIO rats exhibited significant decreases in sucrose consumption (i.e., anhedonia) compared to male DR and male control rats. In the forced swim test (FST), male DIO rats exhibited increases in immobility and decreases in climbing behaviors in the pre-test sessions. Interestingly, male DR rats exhibited these same changes in both the pre-test and test sessions of the FST, suggesting that consumption of a HFD, even in the absence of the development of an obesity phenotype, has behavioral consequences. Female rats did not exhibit differences in sucrose preference, but female DIO rats exhibited increases in immobility exclusively in the test session of the FST, behavioral changes that were not affected by the stage of the estrous cycle. Collectively, these studies demonstrate that access to a HFD elicits different behavioral outcomes in male and female rats.


Assuntos
Comportamento Animal , Depressão , Dieta Hiperlipídica , Obesidade , Animais , Feminino , Masculino , Dieta Hiperlipídica/efeitos adversos , Depressão/etiologia , Obesidade/psicologia , Obesidade/etiologia , Ratos , Ratos Sprague-Dawley , Anedonia , Preferências Alimentares/psicologia , Fatores Sexuais
2.
Brain Behav Immun ; 113: 248-258, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37437820

RESUMO

Gulf War Illness (GWI) collectively describes the multitude of central and peripheral disturbances affecting soldiers who served in the 1990-1991 Gulf War. While the mechanisms responsible for GWI remain elusive, the prophylactic use of the reversible acetylcholinesterase inhibitor, pyridostigmine bromide (PB), and war-related stress have been identified as chief factors in GWI pathology. Post-deployment stress is a common challenge faced by veterans, and aberrant cholinergic and/or immune responses to these psychological stressors may play an important role in GWI pathology, especially the cognitive impairments experienced by many GWI patients. Therefore, the current study investigated if an immobilization stress challenge would produce abnormal responses in PB-treated rats three months later. Results indicate that hippocampal cholinergic responses to an immobilization stress challenge are impaired three months after PB administration. We also assessed if an immune or stress challenge reveals deficits in PB-treated animals during hippocampal-dependent learning and memory tasks at this delayed timepoint. Novel object recognition (NOR) testing paired with either acute saline or lipopolysaccharide (LPS, 30 µg/kg, i.p.), as well as Morris water maze (MWM) testing was conducted approximately three months after PB administration and/or repeated restraint stress. Rats with a history of PB treatment exhibited 24-hour hippocampal-dependent memory deficits when challenged with LPS, but not saline, in the NOR task. Similarly, in the same cohort, PB-treated rats showed 24-hour memory deficits in the MWM task. Ultimately, these studies highlight the long-term effects of PB treatment on hippocampal function and provide insight into the progressive cognitive deficits observed in veterans with GWI.


Assuntos
Disfunção Cognitiva , Síndrome do Golfo Pérsico , Ratos , Animais , Guerra do Golfo , Lipopolissacarídeos , Acetilcolinesterase , Inibidores da Colinesterase/farmacologia , Brometo de Piridostigmina/farmacologia , Transtornos da Memória , Modelos Animais de Doenças
3.
bioRxiv ; 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37162932

RESUMO

Leptin is a homeostatic regulatory element that signals the presence of energy stores -in the form of adipocytes-which ultimately reduces food intake and increases energy expenditure. Similarly, serotonin (5-HT), a signaling molecule found in both the central and peripheral nervous systems, also regulates food intake. Here we use a combination of pharmacological manipulations, optogenetics, retrograde tracing, and in situ hybridization, combined with behavioral endpoints to physiologically and anatomically identify a novel leptin-mediated pathway between 5-HT neurons in the dorsal raphe nucleus (DRN) and hypothalamic arcuate nucleus (ARC) that controls food intake. In this study, we show that microinjecting leptin directly into the DRN reduces food intake in male Sprague-Dawley rats. This effect is mediated by leptin-receptor expressing neurons in the DRN as selective optogenetic activation of these neurons at either their ARC terminals or DRN cell bodies also reduces food intake. Anatomically, we identified a unique population of serotonergic raphe neurons expressing leptin receptors that send projections to the ARC. Finally, by utilizing in vivo microdialysis and high-performance liquid chromatography, we show that leptin administration to the DRN increases 5-HT efflux into the ARC. Overall, this study identifies a novel circuit for leptin-mediated control of food intake through a DRN-ARC pathway, utilizing 5-HT as a mechanism to control feeding behavior. Characterization of this new pathway creates opportunities for understanding how the brain controls eating behavior, as well as opens alternative routes for the treatment of eating disorders. Significance: Leptin and serotonin both play a vital role in the regulation of food intake, yet there is still uncertainty in how these two molecules interact to control appetite. The purpose of this study is to further understand the anatomical and functional connections between leptin receptor expressing neurons in the dorsal raphe nucleus, the main source of serotonin, and the arcuate nucleus of the hypothalamus, and how serotonin plays a role in this pathway to reduce food intake. Insight gained from this study will contribute to a more thorough understanding of the networks that regulate food intake, and open alternative avenues for the development of treatments for obesity and eating disorders.

4.
Neurobiol Stress ; 18: 100446, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35573808

RESUMO

Gulf War Illness (GWI) is a multi-symptom illness that continues to affect over 250,000 American Gulf War veterans. The causes of GWI remain equivocal; however, prophylactic use of the acetylcholinesterase inhibitor pyridostigmine bromide (PB), and the stress of combat have been identified as two potential causative factors. Both PB and stress alter acetylcholine (ACh), which mediates both cognition and anti-inflammatory responses. As inflammation has been proposed to contribute to the cognitive deficits and immune dysregulation in GWI, the goal of this study was to determine the long-term effects of PB and stress on the cholinergic anti-inflammatory pathway in the central nervous system and periphery. We used our previously established rat model of GWI and in vivo microdialysis to assess cholinergic neurochemistry in the prefrontal cortex (PFC) and hippocampus following a mild immune challenge (lipopolysaccharide; LPS). We then examined LPS-induced changes in inflammatory markers in PFC and hippocampal homogenates. We found that PB treatment produces a long-lasting potentiation of the cholinergic response to LPS in both the PFC and hippocampus. Interestingly, this prolonged effect of PB treatment enhancing cholinergic responses to LPS was accompanied by paradoxical increases in the release of pro-inflammatory cytokines in these brain regions. Collectively, these findings provide evidence that neuroinflammation resulting from dysregulation of the cholinergic anti-inflammatory pathway is a mechanistic mediator in the progression of the neurochemical and neurocognitive deficits in GWI and more broadly suggest that dysregulation of this pathway may contribute to neuroinflammatory processes in stress-related neurological disorders.

5.
Neurobiol Stress ; 15: 100354, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34258333

RESUMO

Insulin resistance is a major contributor to the neuroplasticity deficits observed in patients with metabolic disorders. However, the relative contribution of peripheral versus central insulin resistance in the development of neuroplasticity deficits remains equivocal. To distinguish between peripheral and central insulin resistance, we developed a lentiviral vector containing an antisense sequence selective for the insulin receptor (LV-IRAS). We previously demonstrated that intra-hippocampal injection of this vector impairs synaptic transmission and hippocampal-dependent learning and memory in the absence of peripheral insulin resistance. In view of the increased risk for the development of neuropsychiatric disorders in patients with insulin resistance, the current study examined depressive and anxiety-like behaviors, as well as hippocampal structural plasticity in rats with hippocampal-specific insulin resistance. Following hippocampal administration of either the LV-control virus or the LV-IRAS, anhedonia was evaluated by the sucrose preference test, despair behavior was assessed in the forced swim test, and anxiety-like behaviors were determined in the elevated plus maze. Hippocampal neuron morphology was studied by Golgi-Cox staining. Rats with hippocampal insulin resistance exhibited anxiety-like behaviors and behavioral despair without differences in anhedonia, suggesting that some but not all components of depressive-like behaviors were affected. Morphologically, hippocampal-specific insulin resistance elicited atrophy of the basal dendrites of CA3 pyramidal neurons and dentate gyrus granule neurons, and also reduced the expression of immature dentate gyrus granule neurons. In conclusion, hippocampal-specific insulin resistance elicits structural deficits that are accompanied by behavioral despair and anxiety-like behaviors, identifying hippocampal insulin resistance as a key factor in depressive illness.

6.
Neurobiol Stress ; 12: 100210, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32258255

RESUMO

Pyridostigmine bromide (PB) was administered to soldiers during the first Gulf War as a prophylactic treatment to protect against toxicity in the event of exposure to nerve agents. Although originally thought to pose minimal risk to soldiers, epidemiological studies have since correlated PB administration with the development of a variety of symptoms, including cognitive dysfunction, termed Gulf War Illness (GWI). We previously demonstrated in a rodent model of GWI that central cholinergic responses were altered to various stimuli. In the current study we used in vivo microdialysis to examine how combinations of PB and repeated restraint stress (RRS) altered extracellular glutamate levels in response to an innate immune challenge (lipopolysaccharide; LPS) and an immobilization stress challenge in the prefrontal cortex (PFC) and hippocampus. There were four groups in this study: vehicle non-stressed control (Veh-NSC), vehicle-stressed (Veh-RRS), PB-NSC, and PB-RRS. While LPS decreased glutamate levels in PB-treated rats relative to vehicle-treated rats in the PFC, PB and stress interacted to attenuate LPS-induced decreases in hippocampal glutamate levels. Although immobilization stress increased glutamate in the PFC, glutamate levels in PB-NSC rats failed to recover in the post-stress period relative to vehicle-treated rats. In the hippocampus, PB-stressed rats failed to exhibit habituation of the glutamate response to immobilization stress relative to vehicle-stressed rats. Collectively, these results indicate that PB and stress interacted to produce brain-region specific effects on glutamate neurochemistry, providing insight into the potential mechanisms underlying interactions between the immune system and persistent cognitive dysfunction in veterans with GWI.

7.
Brain Behav Immun ; 80: 384-393, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30953774

RESUMO

Gulf War Illness (GWI) is characterized by a constellation of symptoms that includes cognitive dysfunction. While the causes for GWI remain unknown, prophylactic use of the acetylcholinesterase inhibitor pyridostigmine bromide (PB) in combination with the stress of deployment has been proposed to be among the causes of the cognitive dysfunction in GWI. Mechanistically, clinical studies suggest that altered immune function may be an underlying factor in the neurochemical and neurobehavioral complications of GWI. Accordingly, the goal of this study was to determine how responses to an immune challenge (lipopolysaccharide; LPS) or stress impacts inflammation, acetylcholine (ACh) neurochemistry and behavior in an experimental model of GWI. Rats with a history of PB treatment exhibited potentiated increases in C-reactive protein levels in response to a submaximal LPS challenge compared to control rats, indicating that prior treatment with this cholinesterase inhibitor leads to exacerbated inflammatory responses to a subsequent immune challenge. ACh responses to LPS administration were decreased in the hippocampus, but not prefrontal cortex (PFC), in rats with a prior history of PB treatment or stress exposure. Additionally, ACh release in response to acute immobilization stress was attenuated in the PFC and hippocampus in these groups. These attenuated cholinergic responses were accompanied by impairments in contextual and cue-based fear learning. The results of this study suggest that stress and LPS challenges adversely affect central ACh neurochemistry in a rodent model of GWI and support the hypothesis that dysregulated immune responses are mechanistically linked to the neurological complications of GWI.


Assuntos
Acetilcolina/imunologia , Inibidores da Colinesterase/administração & dosagem , Inflamação/imunologia , Síndrome do Golfo Pérsico/imunologia , Brometo de Piridostigmina/administração & dosagem , Estresse Psicológico/imunologia , Animais , Comportamento Animal/efeitos dos fármacos , Proteína C-Reativa/imunologia , Condicionamento Clássico/efeitos dos fármacos , Condicionamento Clássico/fisiologia , Modelos Animais de Doenças , Medo/efeitos dos fármacos , Medo/fisiologia , Hipocampo/efeitos dos fármacos , Hipocampo/imunologia , Inflamação/induzido quimicamente , Inflamação/complicações , Lipopolissacarídeos/administração & dosagem , Masculino , Síndrome do Golfo Pérsico/complicações , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/imunologia , Ratos Sprague-Dawley , Estresse Psicológico/induzido quimicamente , Estresse Psicológico/complicações
8.
Psychoneuroendocrinology ; 96: 195-202, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30041099

RESUMO

During the Gulf War, prophylactic treatment with pyridostigmine bromide (PB) along with the stress of deployment may have caused unexpected alterations in neural and immune function, resulting in a host of cognitive deficits which have become clinically termed Gulf War Illness (GWI). In order to test this interaction between PB and stress, the following study used a rodent model of GWI to examine how combinations of repeated restraint stress and PB induced alterations of peripheral cholinesterase (ChE) activity, corticosterone (CORT) levels, and cytokines on the last day of treatment, and then 10 days and three months post-treatment. Results indicate that PB decreases ChE activity acutely but sensitizes it by three months post-treatment selectively in rats subjected to stress. Similarly, while stress increased CORT levels acutely, rats in the PB/stressed condition continued to exhibit elevations in CORT at the delayed time point, indicating that PB and stress interact to progressively disrupt homeostasis in several peripheral measures. Because memory deficits are also common in clinical populations with GWI, we examined the effects of PB and stress on contextual fear conditioning. PB exacerbates stress-induced impairments in contextual fear conditioning ten days post-treatment, but protects against stress-induced augmentation of contextual fear conditioning at three months post-treatment. Collectively, these results provide critical insight as to how PB and stress may interact to contribute to the pathophysiological progression of GWI.


Assuntos
Síndrome do Golfo Pérsico/fisiopatologia , Brometo de Piridostigmina/efeitos adversos , Estresse Psicológico/fisiopatologia , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Colinesterases/efeitos dos fármacos , Corticosterona/metabolismo , Citocinas/efeitos dos fármacos , Modelos Animais de Doenças , Guerra do Golfo , Masculino , Transtornos da Memória/psicologia , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/metabolismo , Fatores de Tempo
10.
Mol Psychiatry ; 21(6): 823-30, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26416546

RESUMO

Excitatory amino-acid transporters (EAATs) bind and transport glutamate, limiting spillover from synapses due to their dense perisynaptic expression primarily on astroglia. Converging evidence suggests that abnormalities in the astroglial glutamate transporter localization and function may underlie a disease mechanism with pathological glutamate spillover as well as alterations in the kinetics of perisynaptic glutamate buffering and uptake contributing to dysfunction of thalamo-cortical circuits in schizophrenia. We explored this hypothesis by performing cell- and region-level studies of EAAT1 and EAAT2 expression in the mediodorsal nucleus of the thalamus in an elderly cohort of subjects with schizophrenia. We found decreased protein expression for the typically astroglial-localized glutamate transporters in the mediodorsal and ventral tier nuclei. We next used laser-capture microdissection and quantitative polymerase chain reaction to assess cell-level expression of the transporters and their splice variants. In the mediodorsal nucleus, we found lower expression of transporter transcripts in a population of cells enriched for astrocytes, and higher expression of transporter transcripts in a population of cells enriched for relay neurons. We confirmed expression of transporter protein in neurons in schizophrenia using dual-label immunofluorescence. Finally, the pattern of transporter mRNA and protein expression in rodents treated for 9 months with antipsychotic medication suggests that our findings are not due to the effects of antipsychotic treatment. We found a compensatory increase in transporter expression in neurons that might be secondary to a loss of transporter expression in astrocytes. These changes suggest a profound abnormality in astrocyte functions that support, nourish and maintain neuronal fidelity and synaptic activity.


Assuntos
Astrócitos/metabolismo , Proteínas de Transporte de Glutamato da Membrana Plasmática/metabolismo , Ácido Glutâmico/metabolismo , Idoso , Sistema X-AG de Transporte de Aminoácidos/metabolismo , Animais , Proteínas de Transporte/genética , Feminino , Expressão Gênica , Humanos , Masculino , Núcleo Mediodorsal do Tálamo/metabolismo , Núcleo Mediodorsal do Tálamo/fisiopatologia , Camundongos , Pessoa de Meia-Idade , Neurônios/metabolismo , RNA Mensageiro/metabolismo , Esquizofrenia/genética , Esquizofrenia/metabolismo , Tálamo/fisiopatologia
11.
J Neurovirol ; 22(3): 389-99, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26689572

RESUMO

The purpose of the present study is to examine the integrity of white matter microstructure among individuals coinfected with HIV and HCV using diffusion tensor imaging (DTI). Twenty-five HIV+ patients, 21 HIV+/HCV+ patients, and 25 HIV- controls were included in this study. All HIV+ individuals were stable on combination antiretroviral therapy (cART; ≥3 months). All participants completed MRI and neuropsychological measures. Clinical variables including liver function, HIV-viral load, and CD4 count were collected from the patient groups. DTI metrics including mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), and fractional anisotropy (FA) from five subregions of the corpus callosum were compared across groups. The HIV+/HCV+ group and HIV+ group were similar in terms of HIV clinical variables. None of the participants met criteria for cirrhosis or fibrosis. Within the anterior corpus callosum, significant differences were observed between both HIV+ groups compared to HIV- controls on DTI measures. HIV+ and HIV+/HCV+ groups had significantly lower FA values and higher MD and RD values compared to HIV- controls; however, no differences were present between the HIV+ and HIV+/HCV+ groups. Duration of HIV infection was significantly related to DTI metrics in total corpus callosum FA only, but not other markers of HIV disease burden or neurocognitive function. Both HIV+ and HIV+/HCV+ individuals had significant alterations in white matter integrity within the corpus callosum; however, there was no evidence for an additive effect of HCV coinfection. The association between DTI metrics and duration of HIV infection suggests that HIV may continue to negatively impact white matter integrity even in well-controlled disease.


Assuntos
Corpo Caloso/diagnóstico por imagem , Infecções por HIV/diagnóstico por imagem , Hepatite C/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Anisotropia , Antivirais/uso terapêutico , Estudos de Casos e Controles , Coinfecção , Corpo Caloso/efeitos dos fármacos , Corpo Caloso/patologia , Corpo Caloso/virologia , Imagem de Tensor de Difusão , Quimioterapia Combinada , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/patogenicidade , HIV-1/fisiologia , Hepacivirus/patogenicidade , Hepacivirus/fisiologia , Hepatite C/tratamento farmacológico , Hepatite C/patologia , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Substância Branca/efeitos dos fármacos , Substância Branca/patologia , Substância Branca/virologia
12.
Transl Psychiatry ; 5: e612, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26241350

RESUMO

Inhibitory neurotransmission is primarily mediated by γ-aminobutyric acid (GABA) activating synaptic GABA type A receptors (GABA(A)R). In schizophrenia, presynaptic GABAergic signaling deficits are among the most replicated findings; however, postsynaptic GABAergic deficits are less well characterized. Our lab has previously demonstrated that although there is no difference in total protein expression of the α1-6, ß1-3 or γ2 GABA(A)R subunits in the superior temporal gyrus (STG) in schizophrenia, the α1, ß1 and ß2 GABA(A)R subunits are abnormally N-glycosylated. N-glycosylation is a posttranslational modification that has important functional roles in protein folding, multimer assembly and forward trafficking. To investigate the impact that altered N-glycosylation has on the assembly and trafficking of GABA(A)Rs in schizophrenia, this study used western blot analysis to measure the expression of α1, α2, ß1, ß2 and γ2 GABA(A)R subunits in subcellular fractions enriched for endoplasmic reticulum (ER) and synapses (SYN) from STG of schizophrenia (N = 16) and comparison (N = 14) subjects and found evidence of abnormal localization of the ß1 and ß2 GABA(A)R subunits and subunit isoforms in schizophrenia. The ß2 subunit is expressed as three isoforms at 52 kDa (ß2(52 kDa)), 50 kDa (ß2(50 kDa)) and 48 kDa (ß2(48 kDa)). In the ER, we found increased total ß2 GABA(A)R subunit (ß2(ALL)) expression driven by increased ß2(50 kDa), a decreased ratio of ß(248 kDa):ß2(ALL) and an increased ratio of ß2(50 kDa):ß2(48 kDa). Decreased ratios of ß1:ß2(ALL) and ß1:ß2(50 kDa) in both the ER and SYN fractions and an increased ratio of ß2(52 kDa):ß(248 kDa) at the synapse were also identified in schizophrenia. Taken together, these findings provide evidence that alterations of N-glycosylation may contribute to GABAergic signaling deficits in schizophrenia by disrupting the assembly and trafficking of GABA(A)Rs.


Assuntos
Encéfalo/metabolismo , Receptores de GABA-A/metabolismo , Esquizofrenia/metabolismo , Idoso , Western Blotting , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Retículo Endoplasmático/química , Feminino , Glicosilação , Humanos , Masculino , Receptores de GABA-A/análise , Receptores de GABA-A/fisiologia , Receptores de GABA-B/metabolismo , Receptores de GABA-B/fisiologia , Esquizofrenia/fisiopatologia , Frações Subcelulares/química , Sinapses/química , Lobo Temporal/química
13.
Transl Psychiatry ; 5: e579, 2015 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-26057049

RESUMO

Dysregulation of the glutamate transporters EAAT1 and EAAT2 and their isoforms have been implicated in schizophrenia. EAAT1 and EAAT2 expression has been studied in different brain regions but the prevalence of astrocytic glutamate transporter expression masks the more subtle changes in excitatory amino acid transporters (EAATs) isoforms in neurons in the cortex. Using laser capture microdissection, pyramidal neurons were cut from the anterior cingulate cortex of postmortem schizophrenia (n = 20) and control (n = 20) subjects. The messenger RNA (mRNA) levels of EAAT1, EAAT2 and the splice variants EAAT1 exon9skipping, EAAT2 exon9skipping and EAAT2b were analyzed by real time PCR (RT-PCR) in an enriched population of neurons. Region-level expression of these transcripts was measured in postmortem schizophrenia (n = 25) and controls (n = 25). The relationship between selected EAAT polymorphisms and EAAT splice variant expression was also explored. Anterior cingulate cortex pyramidal cell expression of EAAT2b mRNA was increased (P < 0.001; 67%) in schizophrenia subjects compared with controls. There was no significant change in other EAAT variants. EAAT2 exon9skipping mRNA was increased (P < 0.05; 38%) at region level in the anterior cingulate cortex with no significant change in other EAAT variants at region level. EAAT2 single-nucleotide polymorphisms were significantly associated with changes in EAAT2 isoform expression. Haloperidol decanoate-treated animals, acting as controls for possible antipsychotic effects, did not have significantly altered neuronal EAAT2b mRNA levels. The novel finding that EAAT2b levels are increased in populations of anterior cingulate cortex pyramidal cells further demonstrates a role for neuronal glutamate transporter splice variant expression in schizophrenia.


Assuntos
Transportador 1 de Aminoácido Excitatório/genética , Proteínas de Transporte de Glutamato da Membrana Plasmática/genética , Giro do Cíngulo/metabolismo , Isoformas de Proteínas/genética , Células Piramidais/metabolismo , RNA Mensageiro/metabolismo , Esquizofrenia/genética , Idoso , Idoso de 80 Anos ou mais , Animais , Antipsicóticos/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Estudos de Casos e Controles , Transportador 1 de Aminoácido Excitatório/metabolismo , Transportador 2 de Aminoácido Excitatório/efeitos dos fármacos , Transportador 2 de Aminoácido Excitatório/genética , Transportador 2 de Aminoácido Excitatório/metabolismo , Feminino , Proteínas de Transporte de Glutamato da Membrana Plasmática/metabolismo , Giro do Cíngulo/efeitos dos fármacos , Haloperidol/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Isoformas de Proteínas/metabolismo , Células Piramidais/efeitos dos fármacos , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Esquizofrenia/metabolismo
14.
Schizophr Res ; 119(1-3): 198-209, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20347576

RESUMO

Dysregulated glutamate neurotransmission has been implicated in the pathophysiology of schizophrenia. In particular, hypofunction of the NMDA glutamate receptor has been proposed to play an important role in mediating cognitive deficits in patients. The two NMDA receptor subunits, NR2A and NR2B, are distinctly regulated during development and are associated with different intracellular pathways and functions, which suggest that these receptors play separate roles in the control of higher cognitive functions such as learning and memory. Trafficking of the NR2B subunit-containing receptor is regulated by a microtubule-associated trafficking complex consisting of the KIF17, APBA1, CASK, and mLin7 proteins. Several studies have demonstrated an integrated functional regulation of this trafficking complex with NR2B receptor subunit expression, which in turn has been linked to higher cognitive functions. In the present work, we investigated whether expression of this NR2B-associated trafficking complex might be abnormal in schizophrenia. We analyzed the expression of KIF17, APBA1, CASK, mLin7A and mLin7C in postmortem brain from patients with schizophrenia a comparison group. Analysis of transcripts for all of these proteins revealed particularly prominent expression in cortical layer III and layer IV, which overlapped with NR2B but not NR2A transcripts. We found altered expression of transcripts for the CASK, ABPA1, and mLin7 molecules and the CASK, mLin7 proteins, suggesting that NR2B-containing NMDA receptor transport could be selectively compromised in schizophrenia, and that these changes likely involve altered NR2B function in a subset of cortical neurons.


Assuntos
Lobo Frontal/patologia , Córtex Pré-Frontal/patologia , Receptores de N-Metil-D-Aspartato/genética , Esquizofrenia/genética , Idoso , Idoso de 80 Anos ou mais , Animais , Antipsicóticos/farmacologia , Caderinas/genética , Proteínas de Transporte/genética , Córtex Cerebral/patologia , Feminino , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Guanilato Quinases/genética , Haloperidol/farmacologia , Humanos , Injeções Intramusculares , Cinesinas/genética , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Neurônios/patologia , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Esquizofrenia/patologia , Transcrição Gênica/genética
15.
Oncogene ; 29(12): 1857-64, 2010 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-20010873

RESUMO

The adenomatous polyposis coli (APC) gene product is mutated in the vast majority of human colorectal cancers. APC negatively regulates the WNT pathway by aiding in the degradation of beta-catenin, which is the transcription factor activated downstream of WNT signaling. APC mutations result in beta-catenin stabilization and constitutive WNT pathway activation, leading to aberrant cellular proliferation. APC mutations associated with colorectal cancer commonly fall in a region of the gene termed the mutation cluster region and result in expression of an N-terminal fragment of the APC protein. Biochemical and molecular studies have revealed localization of APC/Apc to different sub-cellular compartments and various proteins outside of the WNT pathway that associate with truncated APC/Apc. These observations and genotype-phenotype correlations have led to the suggestion that truncated APC bears neomorphic and/or dominant-negative function that support tumor development. To analyze this possibility, we have generated a novel allele of Apc in the mouse that yields complete loss of Apc protein. Our studies reveal that whole-gene deletion of Apc results in more rapid tumor development than the APC multiple intestinal neoplasia (Apc(Min)) truncation. Furthermore, we found that adenomas bearing truncated Apc had increased beta-catenin activity when compared with tumors lacking Apc protein, which could lead to context-dependent inhibition of tumorigenesis.


Assuntos
Polipose Adenomatosa do Colo/genética , Deleção de Genes , Genes APC , Polipose Adenomatosa do Colo/prevenção & controle , Animais , Códon/genética , Códon sem Sentido , Modelos Animais de Doenças , Triagem de Portadores Genéticos , Genótipo , Humanos , Neoplasias Intestinais/genética , Camundongos , Camundongos Endogâmicos C57BL/genética , Família Multigênica/genética , Mutação , Fenótipo , beta Catenina/metabolismo
17.
Ultramicroscopy ; 108(3): 179-95, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18054168

RESUMO

Improved resolution made possible by aberration correction has greatly increased the demands on the performance of all parts of high-end electron microscopes. In order to meet these demands, we have designed and built an entirely new scanning transmission electron microscope (STEM). The microscope includes a flexible illumination system that allows the properties of its probe to be changed on-the-fly, a third-generation aberration corrector which corrects all geometric aberrations up to fifth order, an ultra-responsive yet stable five-axis sample stage, and a flexible configuration of optimized detectors. The microscope features many innovations, such as a modular column assembled from building blocks that can be stacked in almost any order, in situ storage and cleaning facilities for up to five samples, computer-controlled loading of samples into the column, and self-diagnosing electronics. The microscope construction is described, and examples of its capabilities are shown.

18.
Am J Infect Control ; 35(8): 508-15, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17936141

RESUMO

BACKGROUND: Pneumococcal vaccination is recommended for patients aged 65 years and greater; inpatient vaccination has been suggested as means to increase vaccination rates is this population. Our hospital implemented an inpatient pneumococcal vaccination program, and expanded the population of interest to include patients aged 2 to 64 years with risk factors for pneumococcal bacteremia. We studied the outcomes of this program to determine if the rate of pneumococcal vaccination opportunities and pneumococcal vaccination rate could be significantly increased through the application of an in-hospital pneumococcal vaccination program, based on standing orders and assessment by Registered Nurses, when compared to our previous method of physician assessment and written vaccination order for each patient. METHODS: Subjects were inpatients admitted to non-intensive care units of our hospital from August to December of 2004. Cases were aged greater than 65 years, or were greater than 2 years of age with selected risk factors. Patients with previous pneumococcal vaccination with the past five years, in terminal or comfort care, those allergic to vaccine components, patients who received organ or bone marrow transplants in the year prior to the study, and those physicians barred them from the vaccination protocol were excluded. Program effectiveness was evaluated through retrospective evaluation of medical records to determine if subjects had been evaluated for vaccination eligibility, and if subjects were eligible, whether or not they had received pneumococcal vaccination. RESULTS: Overall vaccination opportunity rate after implementation of the standing orders-based program increased form 8.6% to 59.1%, and overall vaccination rates improved form 0% to 15.4%. The study found a statistically significant difference in the rate of pneumococcal vaccination opportunities (chi(2) = 182.46, p = .00) and the pneumococcal vaccination rate (chi(2) = 56, p = .00) between the two methods of assessment and vaccination; these results are attributable to the study intervention. CONCLUSIONS: The study program contributed to increased overall vaccination opportunity and vaccination rates, when compared to the previous method. The overall rates of vaccination attained by this program were often lower than those reported in the existing literature for other program designs; however, this may be due to an unusually high rate of vaccination refusal.


Assuntos
Procedimentos Clínicos , Vacinação em Massa/métodos , Papel do Profissional de Enfermagem , Vacinas Pneumocócicas/uso terapêutico , Infecções Estreptocócicas/prevenção & controle , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Programas de Imunização , Pacientes Internados , Masculino , Vacinação em Massa/estatística & dados numéricos , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Recusa do Paciente ao Tratamento
19.
Cardiovasc Intervent Radiol ; 30(5): 876-81, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17671810

RESUMO

The purpose of this study was to evaluate the fibroid morphology in a cohort of women achieving pregnancy following treatment with uterine artery embolization (UAE) for symptomatic uterine fibroids. A retrospective review of magnetic resonance imaging (MRI) of the uterus was performed to assess pre-embolization fibroid morphology. Data were collected on fibroid size, type, and number and included analysis of follow-up imaging to assess response. There have been 67 pregnancies in 51 women, with 40 live births. Intramural fibroids were seen in 62.7% of the women (32/48). Of these the fibroids were multiple in 16. A further 12 women had submucosal fibroids, with equal numbers of types 1 and 2. Two of these women had coexistent intramural fibroids. In six women the fibroids could not be individually delineated and formed a complex mass. All subtypes of fibroid were represented in those subgroups of women achieving a live birth versus those who did not. These results demonstrate that the location of uterine fibroids did not adversely affect subsequent pregnancy in the patient population investigated. Although this is only a small qualitative study, it does suggest that all types of fibroids treated with UAE have the potential for future fertility.


Assuntos
Embolização Terapêutica , Fertilidade , Infertilidade Feminina/etiologia , Leiomiomatose/patologia , Imageamento por Ressonância Magnética , Complicações na Gravidez/etiologia , Neoplasias Uterinas/patologia , Adulto , Feminino , Seguimentos , Humanos , Infertilidade Feminina/patologia , Infertilidade Feminina/fisiopatologia , Leiomiomatose/irrigação sanguínea , Leiomiomatose/complicações , Leiomiomatose/fisiopatologia , Leiomiomatose/terapia , Pessoa de Meia-Idade , Gravidez , Complicações na Gravidez/patologia , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Neoplasias Uterinas/irrigação sanguínea , Neoplasias Uterinas/complicações , Neoplasias Uterinas/fisiopatologia , Neoplasias Uterinas/terapia
20.
Am J Obstet Gynecol ; 195(5): 1266-71, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16796984

RESUMO

OBJECTIVE: This study was undertaken to evaluate the incidence and outcome of pregnancies after uterine artery embolization (UAE) for symptomatic uterine fibroids. STUDY DESIGN: A retrospective analysis of all pregnancies after UAE by a single interventional radiologist. RESULTS: Fifty-six completed pregnancies were identified in approximately 1200 women after UAE. One hundred eight patients were attempting to become pregnant and 33 of these became pregnant. Thirty-three (58.9%) of the 56 pregnancies had successful outcomes. Six (18.2%) of these were premature. Seventeen (30.4%) pregnancies miscarried. There were 3 terminations, 2 stillbirths, and 1 ectopic pregnancy. Of the 33 deliveries, 24 (72.7%) were delivered by cesarean section. There were 13 elective sections and the indication for 9 was fibroids. There were 6 cases of postpartum hemorrhage (18.2%). CONCLUSION: Compared with the general obstetric population, there is a significant increase in delivery by cesarean section and an increase in preterm delivery, postpartum hemorrhage, miscarriage, and lower pregnancy rates. When taking into account the demographics of the study population, these results can be partly explained. There were no other obstetric risk identified.


Assuntos
Embolização Terapêutica , Leiomiomatose/terapia , Resultado da Gravidez , Gravidez , Neoplasias Uterinas/terapia , Útero/irrigação sanguínea , Aborto Espontâneo/epidemiologia , Adulto , Artérias , Cesárea/estatística & dados numéricos , Feminino , Humanos , Incidência , Taxa de Gravidez , Nascimento Prematuro/epidemiologia , Transtornos Puerperais/epidemiologia , Estudos Retrospectivos , Hemorragia Uterina/epidemiologia
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