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1.
Res Sq ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38746088

RESUMO

The rs6265 single nucleotide polymorphism (SNP) in the gene for brain-derived neurotrophic factor is a common variant that alters therapeutic outcomes for individuals with Parkinson's disease (PD). We previously investigated the effects of this SNP on the experimental therapeutic approach of neural grafting, demonstrating that young adult parkinsonian rats carrying the variant Met allele exhibited enhanced graft function compared to wild-type rats, and also exclusively developed aberrant graft-induced dyskinesias (GID). Aging is the primary risk factor for PD and reduces graft efficacy. Here we investigated whether aging interacts with this SNP to further alter cell transplantation outcomes. We hypothesized that aging would dampen enhancement of graft function associated with this genetic variant and exacerbate GID in all grafted subjects. Unexpectedly, beneficial graft function was maintained in aged rs6265 subjects. However, aging was permissive to GID induction, regardless of genotype, with the greatest incidence and severity found in rs6265 expressing animals.

2.
J Am Heart Assoc ; 12(23): e031530, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38038192

RESUMO

BACKGROUND: Every year the American Heart Association's Resuscitation Science Symposium (ReSS) brings together a community of international resuscitation science researchers focused on advancing cardiac arrest care. METHODS AND RESULTS: The American Heart Association's ReSS was held in Chicago, Illinois from November 4th to 6th, 2022. This annual narrative review summarizes ReSS programming, including awards, special sessions and scientific content organized by theme and plenary session. CONCLUSIONS: By exploring both the science of resuscitation and important related topics including survivorship, disparities, and community-focused programs, this meeting provided important resuscitation updates.


Assuntos
Reanimação Cardiopulmonar , American Heart Association
3.
Exp Neurol ; 369: 114522, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37640098

RESUMO

Dopamine depletion associated with parkinsonism induces plastic changes in striatal medium spiny neurons (MSN) that are maladaptive and associated with the emergence of the negative side-effect of standard treatment: the abnormal involuntary movements termed levodopa-induced dyskinesia (LID). Prevention of MSN dendritic spine loss is hypothesized to diminish liability for LID in Parkinson's disease. Blockade of striatal CaV1.3 calcium channels can prevent spine loss and significantly diminish LID in parkinsonian rats. While pharmacological antagonism with FDA approved CaV1 L-type channel antagonist dihydropyridine (DHP) drugs (e.g, isradipine) are potentially antidyskinetic, pharmacologic limitations of current drugs may result in suboptimal efficacy. To provide optimal CaV1.3 antagonism, we investigated the ability of a dual pharmacological approach to more potently antagonize these channels. Specifically, quinpirole, a D2/D3-type dopamine receptor (D2/3R) agonist, has been demonstrated to significantly reduce calcium current activity at CaV1.3 channels in MSNs of rats by a mechanism distinct from DHPs. We hypothesized that dual inhibition of striatal CaV1.3 channels using the DHP drug isradipine combined with the D2/D3 dopamine receptor agonist quinpirole prior to, and in conjunction with, levodopa would be more effective at preventing structural modifications of dendritic spines and providing more stable LID prevention. For these proof-of-principle studies, rats with unilateral nigrostriatal lesions received daily administration of vehicle, isradipine, quinpirole, or isradipine + quinpirole prior to, and concurrent with, levodopa. Development of LID and morphological analysis of dendritic spines were assessed. Contrary to our hypothesis, quinpirole monotherapy was the most effective at reducing dyskinesia severity and preventing abnormal mushroom spine formation on MSNs, a structural phenomenon previously associated with LID. Notably, the antidyskinetic efficacy of quinpirole monotherapy was lost in the presence of isradipine co-treatment. These findings suggest that D2/D3 dopamine receptor agonists when given in combination with levodopa and initiated in early-stage Parkinson's disease may provide long-term protection against LID. The negative interaction of isradipine with quinpirole suggests a potential cautionary note for co-administration of these drugs in a clinical setting.

4.
PLoS One ; 18(5): e0284480, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37126506

RESUMO

Microglial cells are brain-specific macrophages that swiftly react to disruptive events in the brain. Microglial activation leads to specific modifications, including proliferation, morphological changes, migration to the site of insult, and changes in gene expression profiles. A change in inflammatory status has been linked to many neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease. For this reason, the investigation and quantification of microglial cells is essential for better understanding their role in disease progression as well as for evaluating the cytocompatibility of novel therapeutic approaches for such conditions. In the following study we implemented a machine learning-based approach for the fast and automatized quantification of microglial cells; this tool was compared with manual quantification (ground truth), and with alternative free-ware such as the threshold-based ImageJ and the machine learning-based Ilastik. We first trained the algorithms on brain tissue obtained from rats and non-human primate immunohistochemically labelled for microglia. Subsequently we validated the accuracy of the trained algorithms in a preclinical rodent model of Parkinson's disease and demonstrated the robustness of the algorithms on tissue obtained from mice, as well as from images provided by three collaborating laboratories. Our results indicate that machine learning algorithms can detect and quantify microglial cells in all the three mammalian species in a precise manner, equipotent to the one observed following manual counting. Using this tool, we were able to detect and quantify small changes between the hemispheres, suggesting the power and reliability of the algorithm. Such a tool will be very useful for investigation of microglial response in disease development, as well as in the investigation of compatible novel therapeutics targeting the brain. As all network weights and labelled training data are made available, together with our step-by-step user guide, we anticipate that many laboratories will implement machine learning-based quantification of microglial cells in their research.


Assuntos
Microglia , Doença de Parkinson , Camundongos , Ratos , Animais , Microglia/metabolismo , Doença de Parkinson/metabolismo , Reprodutibilidade dos Testes , Encéfalo , Primatas , Aprendizado de Máquina , Mamíferos
5.
Neurobiol Dis ; 181: 106111, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37001610

RESUMO

In the past 25 years, the prevalence of Parkinson's disease (PD) has nearly doubled. Age remains the primary risk factor for PD and as the global aging population increases this trend is predicted to continue. Even when treated with levodopa, the gold standard dopamine (DA) replacement therapy, individuals with PD frequently develop therapeutic side effects. Levodopa-induced dyskinesia (LID), a common side effect of long-term levodopa use, represents a significant unmet clinical need in the treatment of PD. Previously, in young adult (3-month-old) male parkinsonian rats, we demonstrated that the silencing of CaV1.3 (Cacan1d) L-type voltage-gated calcium channels via striatal delivery of rAAV-CaV1.3-shRNA provides uniform protection against the induction of LID, and significant reduction of established severe LID. With the goal of more closely replicating a clinical demographic, the current study examined the effects of CaV1.3-targeted gene therapy on LID escalation in male and female parkinsonian rats of advanced age (18-month-old at study completion). We tested the hypothesis that silencing aberrant CaV1.3 channel activity in the parkinsonian striatum would prevent moderate to severe dyskinesia with levodopa dose escalation. To test this hypothesis, 15-month-old male and female F344 rats were rendered unilaterally parkinsonian and primed with low-dose (3-4 mg/kg) levodopa. Following the establishment of stable, mild dyskinesias, rats received an intrastriatal injection of either the Cacna1d-specific rAAV-CaV1.3-shRNA vector (CAV-shRNA), or the scramble control rAAV-SCR-shRNA vector (SCR-shRNA). Daily (M-Fr) low-dose levodopa was maintained for 4 weeks during the vector transduction and gene silencing window followed by escalation to 6 mg/kg, then to 12 mg/kg levodopa. SCR-shRNA-shRNA rats showed stable LID expression with low-dose levodopa and the predicted escalation of LID severity with increased levodopa doses. Conversely, complex behavioral responses were observed in aged rats receiving CAV-shRNA, with approximately half of the male and female subjects-therapeutic 'Responders'-demonstrating protection against LID escalation, while the remaining half-therapeutic 'Non-Responders'-showed LID escalation similar to SCR-shRNA rats. Post-mortem histological analyses revealed individual variability in the detection of Cacna1d regulation in the DA-depleted striatum of aged rats. However, taken together, male and female therapeutic 'Responder' rats receiving CAV-shRNA had significantly less striatal Cacna1d in their vector-injected striatum relative to contralateral striatum than those with SCR-shRNA. The current data suggest that mRNA-level silencing of striatal CaV1.3 channels maintains potency in a clinically relevant in vivo scenario by preventing dose-dependent dyskinesia escalation in rats of advanced age. As compared to the uniform response previously reported in young male rats, there was notable variability between individual aged rats, particularly females, in the current study. Future investigations are needed to derive the sex-specific and age-related mechanisms which underlie variable responses to gene therapy and to elucidate factors which determine the therapeutic efficacy of treatment for PD.


Assuntos
Discinesia Induzida por Medicamentos , Doença de Parkinson , Ratos , Masculino , Feminino , Animais , Levodopa/efeitos adversos , Regulação para Baixo , Ratos Sprague-Dawley , Ratos Endogâmicos F344 , Discinesia Induzida por Medicamentos/metabolismo , Dopamina , Doença de Parkinson/tratamento farmacológico , RNA Interferente Pequeno , Antiparkinsonianos/farmacologia , Oxidopamina
6.
Crit Care Explor ; 3(12): e0590, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34909697

RESUMO

OBJECTIVES: To summarize selected meta-analyses and trials related to critical care pharmacotherapy published in 2020. DATA SOURCES: The Clinical Pharmacy and Pharmacology Pharmacotherapy Literature Update group screened 36 journals monthly for impactful publications. STUDY SELECTION: The group reviewed a total of 119 articles during 2020 according to relevance for practice. DATA EXTRACTION: Articles were selected with consensus and importance to clinical practice from those included in the monthly Clinical Pharmacy and Pharmacology Pharmacotherapy Literature Update. The group reviewed articles according to Grading of Recommendations, Assessment, Development, and Evaluations criteria. Articles with a 1A grade were selected. DATA SYNTHESIS: Several trials were summarized, including two meta-analyses and five original research trials. Original research trials evaluating vitamin C, hydrocortisone, and thiamine versus hydrocortisone in sepsis, the use of nonsedation strategies, dexmedetomidine in cardiac surgery, remdesivir for severe acute respiratory syndrome coronavirus 2, and thrombectomy in acute ischemic stroke. Two meta-analyses determining the impact of norepinephrine initiation in patients with septic shock and the use of corticosteroids in severe acute respiratory syndrome coronavirus 2 was included. CONCLUSIONS: This clinical review provides summary and perspectives of clinical practice impact on influential critical care pharmacotherapy publications in 2020.

7.
J Vis Exp ; (176)2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34723950

RESUMO

Levodopa (L-DOPA) remains the gold-standard therapy used to treat Parkinson's disease (PD) motor symptoms. However, unwanted involuntary movements known as L-DOPA-induced dyskinesias (LIDs) develop with prolonged use of this dopamine precursor. It is estimated that the incidence of LIDs escalates to approximately 90% of individuals with PD within 10-15 years of treatment. Understanding the mechanisms of this malady and developing both novel and effective anti-dyskinesia treatments requires consistent and accurate modeling for pre-clinical testing of therapeutic interventions. A detailed method for reliable induction and comprehensive rating of LIDs following 6-OHDA-induced nigral lesioning in a rat model of PD is presented here. Dependable LID assessment in rats provides a powerful tool that can be readily utilized across laboratories to test emerging therapies focused on reducing or eliminating this common treatment-induced burden for individuals with PD.


Assuntos
Discinesia Induzida por Medicamentos , Discinesias , Doença de Parkinson , Animais , Modelos Animais de Doenças , Dopamina , Discinesia Induzida por Medicamentos/tratamento farmacológico , Discinesia Induzida por Medicamentos/etiologia , Discinesias/complicações , Discinesias/tratamento farmacológico , Levodopa/efeitos adversos , Oxidopamina/efeitos adversos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/etiologia , Ratos
8.
Neurobiol Dis ; 148: 105175, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33188920

RESUMO

Prevalent in approximately 20% of the worldwide human population, the rs6265 (also called 'Val66Met') single nucleotide polymorphism (SNP) in the gene for brain-derived neurotrophic factor (BDNF) is a common genetic variant that can alter therapeutic responses in individuals with Parkinson's disease (PD). Possession of the variant Met allele results in decreased activity-dependent release of BDNF. Given the resurgent worldwide interest in neural transplantation for PD and the biological relevance of BDNF, the current studies examined the effects of the rs6265 SNP on therapeutic efficacy and side-effect development following primary dopamine (DA) neuron transplantation. Considering the significant reduction in BDNF release associated with rs6265, we hypothesized that rs6265-mediated dysfunctional BDNF signaling contributes to the limited clinical benefit observed in a subpopulation of PD patients despite robust survival of grafted DA neurons, and further, that this mutation contributes to the development of aberrant graft-induced dyskinesias (GID). To this end, we generated a CRISPR knock-in rat model of the rs6265 BDNF SNP to examine for the first time the influence of a common genetic polymorphism on graft survival, functional efficacy, and side-effect liability, comparing these parameters between wild-type (Val/Val) rats and those homozygous for the variant Met allele (Met/Met). Counter to our hypothesis, the current research indicates that Met/Met rats show enhanced graft-associated therapeutic efficacy and a paradoxical enhancement of graft-derived neurite outgrowth compared to wild-type rats. However, consistent with our hypothesis, we demonstrate that the rs6265 genotype in the host rat is strongly linked to development of GID, and that this behavioral phenotype is significantly correlated with neurochemical signatures of atypical glutamatergic neurotransmission by grafted DA neurons.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Transplante de Células/métodos , Neurônios Dopaminérgicos/transplante , Discinesias/genética , Animais , Antiparkinsonianos/efeitos adversos , Transplante de Células/efeitos adversos , Neurônios Dopaminérgicos/metabolismo , Discinesia Induzida por Medicamentos/etiologia , Discinesias/etiologia , Embrião de Mamíferos , Técnicas de Introdução de Genes , Levodopa/efeitos adversos , Mesencéfalo/citologia , Oxidopamina/toxicidade , Doença de Parkinson Secundária/induzido quimicamente , Ratos , Simpatolíticos/toxicidade , Proteína Vesicular 2 de Transporte de Glutamato/metabolismo
9.
Exp Neurol ; 333: 113413, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32717354

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disease. Pharmacotherapy with L-DOPA remains the gold-standard therapy for PD, but is often limited by the development of the common side effect of L-DOPA-induced dyskinesia (LID), which can become debilitating. The only effective treatment for disabling dyskinesia is surgical therapy (neuromodulation or lesioning), therefore effective pharmacological treatment of LID is a critical unmet need. Here, we show that sub-anesthetic doses of ketamine attenuate the development of LID in a rodent model, while also having acute anti-parkinsonian activity. The long-term anti-dyskinetic effect is mediated by brain-derived neurotrophic factor-release in the striatum, followed by activation of ERK1/2 and mTOR pathway signaling. This ultimately leads to morphological changes in dendritic spines on striatal medium spiny neurons that correlate with the behavioral effects, specifically a reduction in the density of mushroom spines, a dendritic spine phenotype that shows a high correlation with LID. These molecular and cellular changes match those occurring in hippocampus and cortex after effective sub-anesthetic ketamine treatment in preclinical models of depression, and point to common mechanisms underlying the therapeutic efficacy of ketamine for these two disorders. These preclinical mechanistic studies complement current ongoing clinical testing of sub-anesthetic ketamine for the treatment of LID by our group, and provide further evidence in support of repurposing ketamine to treat individuals with PD. Given its clinically proven therapeutic benefit for both treatment-resistant depression and several pain states, very common co-morbidities in PD, sub-anesthetic ketamine could provide multiple therapeutic benefits for PD in the future.


Assuntos
Anestésicos Dissociativos/uso terapêutico , Antiparkinsonianos/efeitos adversos , Discinesia Induzida por Medicamentos/tratamento farmacológico , Ketamina/uso terapêutico , Levodopa/efeitos adversos , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/patologia , Depressão/tratamento farmacológico , Depressão/psicologia , Reposicionamento de Medicamentos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Neurônios/efeitos dos fármacos , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Serina-Treonina Quinases TOR/efeitos dos fármacos
10.
Exp Neurol ; 330: 113327, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32387398

RESUMO

Numerous genes, and alterations in their expression, have been identified as risk factors for developing levodopa-induced dyskinesia (LID). However, our understanding of the complexities of molecular changes remains insufficient for development of clinical treatment. In the current study we used gene array, in situ hybridization, immunohistochemistry, and microdialysis to provide a unique compare and contrast assessment of the relationship of four candidate genes to LID, employing three genetically distinct rat strains (Sprague-Dawley (SD), Fischer-344 (F344) and Lewis-RT.1) showing differences in dyskinesia susceptibility and 'first-ever LID' versus 'chronic LID' expression in subjects displaying equal dyskinesia severity. In these studies, rat strains were easily distinguishable for their LID propensity with: 1) a majority of SD rats expressing LID (LID+) and a subset being resistant (LID-); 2) all F344 rats readily developing (LID+); and 3) all Lewis rats being LID-resistant (LID-). Following chronic levodopa, LID+ SD rats showed significant increases in candidate gene expression: Nr4a2/(Nurr1) > > Trh > Inhba = Fosb. However, SD rats with long-standing striatal dopamine (DA) depletion treated with first-ever versus chronic high-dose levodopa revealed that despite identical levels of LID severity: 1) Fosb and Nurr1 transcripts but not protein were elevated with acute LID expression; 2) FOSB/ΔFOSB and NURR1 proteins were elevated only with chronic LID; and 3) Trh transcript and protein were elevated only with chronic LID. Strikingly, despite similar levodopa-induced striatal DA release in both LID-expressing F344 and LID-resistant Lewis rats, Fosb, Trh, Inhba transcripts were significantly elevated in both strains; however, Nurr1 mRNA was significantly increased only in LID+ F344 rats. These findings suggest a need to reevaluate currently accepted genotype-to-phenotype relationships in the expression of LID, specifically that of Fosb, a transcription factor generally assumed to play a causal role, and Nurr1, a transcription factor that has received significant attention in PD research linked to its critical role in the survival and function of midbrain DA neurons but who's striatal expression, generally below levels of detection, has remained largely unexplored as a regulator of LID. Finally these studies introduce a novel 'model' (inbred F344 vs inbred Lewis) that may provide a powerful tool for investigating the role for 'dyskinesia-resistance' genes downstream of 'dyskinesia-susceptibility' genes in modulating LID expression, a concept that has received considerably less attention and offers a new ways of thinking about antidyskinetic therapies.


Assuntos
Antiparkinsonianos/toxicidade , Discinesia Induzida por Medicamentos/genética , Discinesia Induzida por Medicamentos/metabolismo , Levodopa/toxicidade , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Genótipo , Masculino , Transtornos Parkinsonianos/genética , Transtornos Parkinsonianos/metabolismo , Fenótipo , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew
11.
Mov Disord ; 34(5): 697-707, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31002755

RESUMO

BACKGROUND: Levodopa-induced dyskinesias are an often debilitating side effect of levodopa therapy in Parkinson's disease. Although up to 90% of individuals with PD develop this side effect, uniformly effective and well-tolerated antidyskinetic treatment remains a significant unmet need. The pathognomonic loss of striatal dopamine in PD results in dysregulation and disinhibition of striatal CaV1.3 calcium channels, leading to synaptopathology that appears to be involved in levodopa-induced dyskinesias. Although there are clinically available drugs that can inhibit CaV1.3 channels, they are not adequately potent and have only partial and transient impact on levodopa-induced dyskinesias. METHODS: To provide unequivocal target validation, free of pharmacological limitations, we developed a CaV1.3 shRNA to provide high-potency, target-selective, mRNA-level silencing of striatal CaV1.3 channels and examined its ability to impact levodopa-induced dyskinesias in severely parkinsonian rats. RESULTS: We demonstrate that vector-mediated silencing of striatal CaV1.3 expression in severely parkinsonian rats prior to the introduction of levodopa can uniformly and completely prevent induction of levodopa-induced dyskinesias, and this antidyskinetic benefit persists long term and with high-dose levodopa. In addition, this approach is capable of ameliorating preexisting severe levodopa-induced dyskinesias. Importantly, motoric responses to low-dose levodopa remained intact in the presence of striatal CaV1.3 silencing, indicating preservation of levodopa benefit without dyskinesia liability. DISCUSSION: The current data provide some of the most profound antidyskinetic benefit reported to date and suggest that genetic silencing of striatal CaV1.3 channels has the potential to transform treatment of individuals with PD by allowing maintenance of motor benefit of levodopa in the absence of the debilitating levodopa-induced dyskinesia side effect. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Antiparkinsonianos/efeitos adversos , Canais de Cálcio/genética , Discinesia Induzida por Medicamentos/prevenção & controle , Levodopa/efeitos adversos , Neostriado/metabolismo , Transtornos Parkinsonianos/tratamento farmacológico , Adrenérgicos/toxicidade , Animais , Modelos Animais de Doenças , Discinesia Induzida por Medicamentos/etiologia , Discinesia Induzida por Medicamentos/terapia , Proteínas de Fluorescência Verde , Substâncias Luminescentes , Feixe Prosencefálico Mediano , Oxidopamina/toxicidade , Transtornos Parkinsonianos/induzido quimicamente , Interferência de RNA , RNA Interferente Pequeno , Ratos , Substância Negra , Tirosina 3-Mono-Oxigenase/metabolismo
12.
J Neurosci ; 35(45): 14983-99, 2015 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-26558771

RESUMO

The striatum is essential for many aspects of mammalian behavior, including motivation and movement, and is dysfunctional in motor disorders such as Parkinson's disease. The vesicular glutamate transporter 3 (VGLUT3) is expressed by striatal cholinergic interneurons (CINs) and is thus well positioned to regulate dopamine (DA) signaling and locomotor activity, a canonical measure of basal ganglia output. We now report that VGLUT3 knock-out (KO) mice show circadian-dependent hyperlocomotor activity that is restricted to the waking cycle and is due to an increase in striatal DA synthesis, packaging, and release. Using a conditional VGLUT3 KO mouse, we show that deletion of the transporter from CINs, surprisingly, does not alter evoked DA release in the dorsal striatum or baseline locomotor activity. The mice do, however, display changes in rearing behavior and sensorimotor gating. Elevation of DA release in the global KO raised the possibility that motor deficits in a Parkinson's disease model would be reduced. Remarkably, after a partial 6-hydroxydopamine (6-OHDA)-mediated DA depletion (∼70% in dorsal striatum), KO mice, in contrast to WT mice, showed normal motor behavior across the entire circadian cycle. l-3,4-dihydroxyphenylalanine-mediated dyskinesias were also significantly attenuated. These findings thus point to new mechanisms to regulate basal ganglia function and potentially treat Parkinson's disease and related disorders. SIGNIFICANCE STATEMENT: Dopaminergic signaling is critical for both motor and cognitive functions in the mammalian nervous system. Impairments, such as those found in Parkinson's disease patients, can lead to severe motor deficits. Vesicular glutamate transporter 3 (VGLUT3) loads glutamate into secretory vesicles for neurotransmission and is expressed by discrete neuron populations throughout the nervous system. Here, we report that the absence of VGLUT3 in mice leads to an upregulation of the midbrain dopamine system. Remarkably, in a Parkinson's disease model, the mice show normal motor behavior. They also show fewer abnormal motor behaviors (dyskinesias) in response to l-3,4-dihydroxyphenylalanine, the principal treatment for Parkinson's disease. The work thus suggests new avenues for the development of novel treatment strategies for Parkinson's disease and potentially other basal-ganglia-related disorders.


Assuntos
Sistemas de Transporte de Aminoácidos Acídicos/deficiência , Ritmo Circadiano/fisiologia , Dopamina/biossíntese , Discinesia Induzida por Medicamentos/metabolismo , Transtornos das Habilidades Motoras/metabolismo , Transtornos Parkinsonianos/metabolismo , Sistemas de Transporte de Aminoácidos Acídicos/genética , Animais , Modelos Animais de Doenças , Discinesia Induzida por Medicamentos/prevenção & controle , Feminino , Levodopa/toxicidade , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Transtornos das Habilidades Motoras/prevenção & controle , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/prevenção & controle
13.
Neurobiol Dis ; 77: 191-203, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25771169

RESUMO

Advanced age is the primary risk factor for Parkinson's disease (PD). In PD patients and rodent models of PD, advanced age is associated with inferior symptomatic benefit following intrastriatal grafting of embryonic dopamine (DA) neurons, a pattern believed to result from decreased survival and reinnervation provided by grafted neurons in the aged host. To help understand the capacity of the aged, parkinsonian striatum to be remodeled with new DA terminals, we used a grafting model and examined whether increasing the number of grafted DA neurons in aged rats would translate to enhanced behavioral recovery. Young (3months), middle-aged (15months), and aged (22months) parkinsonian rats were grafted with proportionately increasing numbers of embryonic ventral mesencephalic (VM) cells to evaluate whether the limitations of the graft environment in subjects of advancing age can be offset by increased numbers of transplanted neurons. Despite robust survival of grafted neurons in aged rats, reinnervation of striatal neurons remained inferior and amelioration of levodopa-induced dyskinesias (LID) was delayed or absent. This study demonstrates that: 1) counter to previous evidence, under certain conditions the aged striatum can support robust survival of grafted DA neurons; and 2) unknown factors associated with the aged striatum result in inferior integration of graft and host, and continue to present obstacles to full therapeutic efficacy of DA cell-based therapy in this model of aging.


Assuntos
Envelhecimento , Corpo Estriado/fisiologia , Neurônios Dopaminérgicos/fisiologia , Doença de Parkinson/cirurgia , Recuperação de Função Fisiológica/fisiologia , Transplante de Células-Tronco/métodos , Anfetamina/farmacologia , Animais , Corpo Estriado/cirurgia , Modelos Animais de Doenças , Fosfoproteína 32 Regulada por cAMP e Dopamina/metabolismo , Discinesia Induzida por Medicamentos/fisiopatologia , Embrião de Mamíferos , Lateralidade Funcional , Levodopa/efeitos adversos , Neuritos/fisiologia , Oxidopamina/toxicidade , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/etiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Endogâmicos F344 , Substância P/metabolismo
14.
J Emerg Med ; 47(5): 513-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25214177

RESUMO

BACKGROUND: Analyses of patient flow through the emergency department (ED) typically focus on metrics such as wait time, total length of stay (LOS), or boarding time. Less is known about how much interaction a patient has with clinicians after being placed in a room, or what proportion of their in-room visit is also spent waiting. OBJECTIVE: Our aim was to assess the proportion of time that a patient spent in conversation with providers during an ED visit. METHODS: Seventy-four audio-taped encounters of patients with low-acuity diagnoses were analyzed. Recorded ED visits were edited to remove downtime. The proportion of time the patient spent in conversation with providers (talk-time) was calculated as follows: (talk-time = [edited audio time/{LOS - door-to-doctor time}]). RESULTS: Participants were 46% male; mean age was 41 years (standard deviation 15.7 years). Median LOS was 126 min (interquartile range [IQR] 96 to 163 min), median time in a patient care area was 76 min (IQR 55 to 122 min). Median time in conversation with providers was 19 min (IQR 14 to 27 min), corresponding to a talk-time percentage of 24.9% (IQR 17.8%-35%). Multivariable regression analysis revealed that patients with older age, longer visits, and those requiring a procedure had more talk-time: total talk-time = 13 s + 9 s × (total time in room in minutes) + 8 s × (years in age of patient) + 482 s × (procedural diagnosis). CONCLUSIONS: Approximately 75% of a patient's time in a care area is spent not interacting with providers. Although some of the time waiting is out of the providers' control (eg, awaiting imaging studies), this significant downtime represents an opportunity for both process improvement efforts and innovative patient-education efforts to make use of remaining downtime.


Assuntos
Comunicação , Serviço Hospitalar de Emergência/estatística & dados numéricos , Relações Médico-Paciente , Adulto , Fatores Etários , Feminino , Humanos , Lacerações/diagnóstico , Lacerações/terapia , Tempo de Internação/estatística & dados numéricos , Dor Lombar/diagnóstico , Dor Lombar/terapia , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Gravação em Fita , Fatores de Tempo
15.
J Emerg Nurs ; 38(3): 273-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22204885

RESUMO

INTRODUCTION: Opioid abuse and overdose have increased drastically in recent years. Diversion of opioids used to treat pain, either through theft or sharing, is increasing and may contribute to this misuse. Based on these trends, we designed a study to investigate opioid storage and disposal practices of patients who were prescribed these agents in the emergency department. METHODS: A prospective cohort pilot study was conducted. All adults (aged ≥18 years) with a chief complaint of either minor musculoskeletal trauma, renal colic, or acute back pain who were discharged home with an opioid prescription were eligible for inclusion; persons with chronic pain were excluded. Patients were asked to participate in two home interviews in which the research assistant viewed the storage location of the opioid prescription. Safe storage was defined as being stored in a locked container or cabinet. Safe disposal was defined as returning the drugs to a designated location or mixing unused pills with an undesirable substance, placing in a sealable container, and then in the trash. Patients self-reported disposal methods. Feasibility of study methods evaluated the ability to conduct home interviews after the ED visit. Descriptive statistics were used to analyze the data. RESULTS: Twenty-five subjects consented to participate; 20 patients completed both home interviews. None of the medications were safely stored. Only 1 patient disposed of the medication, yet did so improperly. CONCLUSION: This pilot study revealed widespread improper storage and disposal of opioids. The study has major implications for education for ED physicians, nurses, and residents.


Assuntos
Analgésicos Opioides/uso terapêutico , Armazenamento de Medicamentos/métodos , Serviço Hospitalar de Emergência , Eliminação de Resíduos/métodos , Adulto , Idoso , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Projetos Piloto , Estudos Prospectivos
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