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BACKGROUND: The ongoing Pan-European Real Life (PEARL) phase 4 study is evaluating fremanezumab effectiveness and safety for the prevention of episodic and chronic migraine. This interim analysis reports primary, secondary and exploratory endpoints from when 500 participants completed at least six months of treatment. METHODS: Adults with episodic migraine or chronic migraine maintaining daily headache diaries were enrolled upon initiation of fremanezumab. Primary endpoint: proportion of participants with ≥50% reduction in monthly migraine days during the six-month period after fremanezumab initiation. Secondary endpoints: mean change from baseline across months 1-12 in monthly migraine days, acute migraine medication use, and headache-related disability. Exploratory endpoint: mean change in headache severity from baseline across months 1-12. Safety was assessed through adverse events reported. RESULTS: Overall, 897 participants were enrolled and 574 included in the effectiveness analyses (episodic migraine, 25.8%; chronic migraine, 74.2%). Of participants with data available, 175/313 (55.9%) achieved ≥50% monthly migraine days reduction during the six-month period post-initiation. Across months 1-12, there were sustained reductions in mean monthly migraine days, acute medication use, disability scores, and headache severity. Few adverse events were reported. CONCLUSION: PEARL interim results support the effectiveness and safety of fremanezumab for migraine prevention in a real-world population across several European countries.Trial registration: encepp.eu: EUPAS35111.
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Anticuerpos Monoclonales , Trastornos Migrañosos , Adulto , Humanos , Estudios Prospectivos , Trastornos Migrañosos/tratamiento farmacológico , Trastornos Migrañosos/prevención & control , CefaleaRESUMEN
Objective: To report the efficacy of different anti-calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs) on headache frequency, intensity, and duration. Background: Blockade of CGRP receptors or neuropeptide with anti-CGRP mAbs have been successfully used for several years for the prevention of chronic and episodic migraine. The response is usually assessed by improvement seen in the number of days with headache per month. However, clinical praxis indicates that sole reliance on the frequency of headaches might be insufficient to interpret the efficacy of these treatments. Methods: Retrospective review of a case with a meticulous headache diary who has tried three different anti-CGRP mAbs for chronic migraine prevention. Results: The patient has been diagnosed with chronic migraine and was first treated with erenumab, followed by fremanezumab and thereafter galcanezumab due to several reasons. In addition to significant improvement in all three parameters analyzed with anti-CGRP mAb treatment, the most important and valuable effect on the patient's quality of life was decreased duration and frequency of headaches. At present, the patient is receiving fremanezumab treatment with an excellent tolerability. Conclusion: There is a clear need for careful follow-up and detailed daily records of headaches showing the frequency, duration, and severity for the evaluation of anti-CGRP mAbs treatment. This study shows the importance of this information in order for medical professionals to make an informed decision regarding the best course of anti-CGRP mAbs treatment in cases of side effects or lack of efficacy.
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Tremor can be highly incapacitating in everyday life and typically fluctuates depending on motor state, medication status as well as external factors. For tremor patients being treated with deep-brain stimulation (DBS), adapting the intensity and pattern of stimulation according the current needs therefore has the potential to generate better symptomatic relief. We here describe a procedure for how patients independently could perform self-tests in their home to generate sensor data for on-line adjustments of DBS parameters. Importantly, the inertia sensor technology needed exists in any standard smartphone, making the procedure widely accessible. Applying this procedure, we have characterized detailed features of tremor patterns displayed by both Parkinson's disease and essential tremor patients and directly compared measured data against both clinical ratings (Fahn-Tolosa-Marin) and finger-attached inertia sensors. Our results suggest that smartphone accelerometry, when used in a standardized testing procedure, can provide tremor descriptors that are sufficiently detailed and reliable to be used for closed-loop control of DBS.
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Parkinson's disease (PD) is a complex, chronic, and progressive neurodegenerative disease that is characterized by irreversible dopaminergic neuronal loss in the substantia nigra. Alpha-synuclein is normally a synaptic protein that plays a key role in PD due to pathological accumulation as oligomers or fibrils. Clustered alpha-synuclein binds to the Toll-like receptors and activates the microglia, which initiates a process that continues with pro-inflammatory cytokine production and secretion. Pro-inflammatory cytokine overproduction and secretion induce cell death and accelerate PD progression. Microglia are found in a resting state in physiological conditions. Microglia became activated by stimulating Toll-like receptors on it under pathological conditions, such as alpha-synuclein aggregation, environmental toxins, or oxidative stress. The interaction between Toll-like receptors and its downstream pathway triggers an activation series, leads to nuclear factor-kappa B activation, initiates the inflammasome formation, and increases cytokine levels. This consecutive inflammatory process leads to dopaminergic cell damage and cell death. Microglia become overactive in response to chronic inflammation, which is observed in PD and causes excessive cytotoxic factor production, such as reactive oxidase, nitric oxide, and tumor necrosis factor-alpha. This inflammatory process contributes to the exacerbation of pathology by triggering neuronal damage or death. Current treatments, such as dopaminergic agonists, anticholinergics, or monoamine oxidase inhibitors alleviate PD symptoms, but they can not stop the disease progression. Finding a radical treatment option or stopping the progression is essential when considering that PD is the second most reported neurodegenerative disorder. Many cytokines are released during inflammation, and they can start the phagocytic process, which caused the degradation of infected cells along with healthy ones. Therefore, targeting the pathological mechanisms, such as microglial activation, mitochondrial dysfunction, and oxidative stress, that should be involved in the treatment program is important. Neuroinflammation is one of the key factors involved in PD pathogenesis as well as alpha-synuclein accumulation, synaptic dysfunction, or dopaminergic neuronal loss, especially in the substantia nigra. Therefore, evaluating the therapeutic efficiency of the mechanisms is important, such as microglial activation and nuclear factor-kappa B pathway or inflammasome formation inhibition, and cytokine release interruption against neuroinflammation may create new treatment possibilities for PD. This study examined the pathological relation between PD and neuroinflammation, and targeting neuroinflammation as an opportunity for PD treatments, such as Toll-like receptor antagonists, NOD-like receptor family pyrin domain containing-3 inflammasome inhibitors, cytokine inhibitors, peroxisome proliferator-activated receptor-γ agonists, reactive oxygen species inhibitors, and nonsteroidal anti-inflammatory drugs.
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Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Citocinas/metabolismo , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/patología , Humanos , Inflamasomas/metabolismo , Inflamación , Enfermedades Neurodegenerativas/complicaciones , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/patología , Enfermedades Neuroinflamatorias , Enfermedad de Parkinson/tratamiento farmacológico , alfa-Sinucleína/metabolismo , alfa-Sinucleína/toxicidadRESUMEN
INTRODUCTION: Lithium has proven efficacy in bipolar affective disorder (BAD) but induces tremor as a side effect in a quarter of patients. Lithium tremor (LT) shares some clinical characteristics of essential tremor (ET) and Parkinson's disease tremor (PT), which might cause difficulties in differential diagnosis. Furthermore, current knowledge of LT is lacking detailed electrophysiological characterization. Here, we present detailed spectral attributes of accelerometric tremor recordings as a diagnostic tool for LT. METHODS: 10 patients (7 males, 3 females) between ages of 29-68, who were on lithium for BAD for 2-12 years, were evaluated for hand tremor with the spectral analysis of accelerometric recordings with different postures. Tremor severity was rated clinically on WHIGET (Washington Heights-Inwood Genetic Study of Essential Tremor) scale. Results were analyzed in comparison to results of ET (n=19) and PT (n=19) patients from our database. RESULTS: LT was most prominent at extensor postures with an average peak frequency (PF) of 8.0±0.3 Hz and an extremely low amplitude, high harmonic components and high noise level. The average PF of LT was similar to that of ET (7.3±0.4 Hz), but higher than that of PT (5.3±0.2 Hz) (p<0.0001). With weight loading, the PF of LT showed an increase of 1.3 Hz. Average amplitude of PT was higher than that of both LT and ET (p<0.0001); harmonic components of LT was comparable to PT whereas noise levels were similar to that of ET. Mean WHIGET score of LT (6.5±0.5) was significantly lower than that of ET (13.1±1) (p<0.0001). CONCLUSION: Electrophysiological features detected by accelerometry may help in differential diagnosis of LT from ET and PT.
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Anti-LGI-1 encephalitis is a type of autoimmune encephalopathy, where antibodies react against the cell surface protein leucine-rich glioma inactivated protein 1 (LGI-1). It presents with a subacute confusion, changes in behaviour, short-term memory deficits and seizures. A piloerectile semiology is common, which has been described as reflecting insular ictal activity. Patients may have temporal lobe abnormalities on brain MRI and EEG. More than half of the patients with limbic encephalitis associated with anti-LGI1 antibodies have hyponatremia. The diagnosis of anti-LGI-1 encephalitis can be made by the detection of antibodies against LGI-1 in serum and/or cerebrospinal fluid. Prompt diagnosis and treatment are important to avoid long-term disability. This case report describes a man with episodes of goose bumps and mild confusion caused by anti-LGI-1 encephalitis.
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Encefalitis , Enfermedad de Hashimoto , Encefalitis Límbica , Autoanticuerpos , Encefalitis/complicaciones , Humanos , Péptidos y Proteínas de Señalización Intracelular/inmunología , Masculino , ProteínasRESUMEN
Dyskinesia is a major side effect of an otherwise effective L-DOPA treatment in Parkinson's patients. The prevailing view for the underlying presynaptic mechanism of L-DOPA-induced dyskinesia (LID) suggests that surges in dopamine (DA) via uncontrolled release from serotonergic terminals results in abnormally high level of extracellular striatal dopamine. Here we used high-sensitivity online microdialysis and PET imaging techniques to directly investigate DA release properties from serotonergic terminals both in the parkinsonian striatum and after neuronal transplantation in 6-OHDA lesioned rats. Although L-DOPA administration resulted in a drift in extracellular DA levels, we found no evidence for abnormally high striatal DA release from serotonin neurons. The extracellular concentration of DA remained at or below levels detected in the intact striatum. Instead, our results showed that an inefficient release pool of DA associated with low D2 receptor binding remained unchanged. Taken together, these findings suggest that differential DA receptor activation rather than excessive release could be the underlying mechanism explaining LID seen in this model. Our data have important implications for development of drugs targeting the serotonergic system to reduce DA release to manage dyskinesia in patients with Parkinson's disease.
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Discinesia Inducida por Medicamentos/metabolismo , Levodopa/efectos adversos , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Receptores Dopaminérgicos/metabolismo , Animales , Benzamidas , Modelos Animales de Enfermedad , Dopamina/metabolismo , Discinesia Inducida por Medicamentos/patología , Espacio Extracelular/metabolismo , Femenino , Levodopa/administración & dosificación , Levodopa/farmacología , Levodopa/uso terapéutico , Microdiálisis , Neostriado/efectos de los fármacos , Neostriado/metabolismo , Nomifensina/uso terapéutico , Enfermedad de Parkinson/diagnóstico por imagen , Tomografía de Emisión de Positrones , Proteínas Proto-Oncogénicas c-fos/metabolismo , Pirrolidinas , Ratas Sprague-Dawley , Serotonina/metabolismoRESUMEN
We used a single adeno-associated viral (AAV) vector co-expressing tyrosine hydroxylase (TH) and GTP cyclohydrolase 1 (GCH1) to investigate the relationship between vector dose, and the magnitude and rate of recovery in hemi-parkinsonian rats. Intrastriatal injections of >1E10 genomic copies (gc) of TH-GCH1 vector resulted in complete recovery in drug-naïve behavior tests. Lower vector dose gave partial to no functional improvement. Stereological quantification revealed no striatal NeuN+ cell loss in any of the groups, whereas a TH-GCH1 dose of >1E11 gc resulted in cell loss in globus pallidus. Thus, a TH-GCH1 dose of 1E10 gc gave complete recovery without causing neuronal loss. Safety and efficacy was also studied in non-human primates where the control vector resulted in co-expression of the transgenes in caudate-putamen. In the TH-GCH1 group, GCH1 expression was robust but TH was not detectable. Moreover, TH-GCH1 treatment did not result in functional improvement in non-human primates.
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Dependovirus/genética , Modelos Animales de Enfermedad , Vectores Genéticos , Levodopa/biosíntesis , Enfermedad de Parkinson/tratamiento farmacológico , Animales , Levodopa/uso terapéutico , Ratas , Transducción Genética , TransgenesRESUMEN
Alpha-synuclein phosphorylated at serine 129 (S129) is highly elevated in Parkinson's disease patients where it mainly accumulates in the Lewy bodies. Several groups have studied the role of phosphorylation at the S129 in α-synuclein in a rat model for Parkinson's disease using recombinant adeno-associated viral (rAAV) vectors. The results obtained are inconsistent and accordingly the role of S129 phosphorylation in α-synuclein toxicity remains unclear. This prompted us to re-examine the neuropathological and behavioral effects of the S129 modified α-synuclein species in vivo. For this purpose, we used two mutated forms of human α-synuclein in which the S129 was replaced either with an alanine (S129A), to block phosphorylation, or with an aspartate (S129D), to mimic phosphorylation, and compared them with the wild type α-synuclein. This approach was similar in design to previous studies, however our investigation of dopaminergic degeneration also included performing a detailed study of the α-synuclein induced pathology in the striatum and the analysis of motor deficits. Our results showed that overexpressing S129D or wild type α-synuclein resulted in an accelerated dopaminergic fiber loss as compared with S129A α-synuclein. Furthermore, the motor deficit seen in the group treated with the mutant S129D α-synuclein appeared earlier than the other two forms of α-synuclein. Conversely, S129A α-synuclein showed significantly larger pathological α-synuclein-positive inclusions, and slower dopaminergic fiber loss, when compared to the other two forms of α-synuclein, suggesting a neuroprotective effect of the mutation. When examined at long-term, all three α-synuclein forms resulted in pathological accumulations of α-synuclein in striatal fibers and dopaminergic cell death in the substantia nigra. Our data show that changes in the S129 residue of α-synuclein influence the rate of pathology and neurodegeneration, with an overall deleterious effect of exchanging S129 to a residue mimicking its phosphorylated state.
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Trastornos del Movimiento/genética , Trastornos del Movimiento/patología , Mutación/fisiología , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/patología , Serina/genética , alfa-Sinucleína/genética , alfa-Sinucleína/toxicidad , Animales , Conducta Animal/efectos de los fármacos , Western Blotting , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Densitometría , Dependovirus/genética , Dopamina/fisiología , Femenino , Vectores Genéticos , Inmunohistoquímica , Fosforilación , Ratas , Ratas Sprague-Dawley , TransgenesRESUMEN
Although α-synuclein (α-SYN) aggregation is a hallmark of sporadic and familial Parkinson's disease (PD), it is not known how it contributes to early events of PD pathogenesis such as oxidative and inflammatory stress. Here, we addressed this question in a new animal model based on stereotaxic delivery of an adeno-associated viral vector (rAAV) for expression of human α-SYN in the ventral midbrain of mice lacking the transcription factor Nrf2 (Nrf2(-/-)). Two months after surgery, Nrf2(-/-) mice exhibited exacerbated degeneration of nigral dopaminergic neurons and increased dystrophic dendrites, reminiscent of Lewy neurites, which correlated with impaired proteasome gene expression and activity. Dopaminergic neuron loss was associated with an increase in neuroinflammation and gliosis that were intensified in Nrf2(-/-) mice. In response to exogenously added α-SYN, Nrf2(-/-) microglia failed to activate the expression of two anti-inflammatory genes, heme oxygenase-1 (HO-1) and nicotinamide adenine dinucleotide phosphate quinone oxidorreductase-1 (NQO1). This impaired Nrf2 response correlated with a shift in the microglial activation profile, towards increased production of proinflammatory markers, IL-6, IL-1ß and iNOS and reduced phagocytic capacity of fluorescent beads, and lower messenger RNA levels for TAM receptors Axl and Mer. Postmortem brain tissue samples from patients in early- to middle-stage progression of PD showed increased HO-1 expression in astrocytes and microglia, suggesting an attempt of the diseased brain to compensate these hallmarks of PD through activation of the Nrf2 pathway. This study demonstrates that α-SYN and Nrf2 deficiency cooperate on protein aggregation, neuroinflammation and neuronal death and provides a bifactorial animal model to study early-stage PD.
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Factor 2 Relacionado con NF-E2/deficiencia , Neuronas/citología , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/inmunología , alfa-Sinucleína/genética , Animales , Muerte Celular , Células Cultivadas , Modelos Animales de Enfermedad , Expresión Génica , Hemo-Oxigenasa 1/genética , Hemo-Oxigenasa 1/inmunología , Humanos , Ratones , Ratones Noqueados , Ratones Transgénicos , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/inmunología , Neuronas/inmunología , Enfermedad de Parkinson/patología , Enfermedad de Parkinson/fisiopatología , alfa-Sinucleína/química , alfa-Sinucleína/inmunologíaRESUMEN
Preclinical efficacy of continuous delivery of 3,4-dihydroxyphenylalanine (DOPA) with adeno-associated viral (AAV) vectors has recently been documented in animal models of Parkinson's disease (PD). So far, all studies have utilized a mix of two monocistronic vectors expressing either of the two genes, tyrosine hydroxylase (TH) and GTP cyclohydrolase-1 (GCH1), needed for DOPA production. Here, we present a novel vector design that enables efficient DOPA production from a single AAV vector in rats with complete unilateral dopamine (DA) lesions. Functional efficacy was assessed with drug-induced and spontaneous motor behavioral tests where vector-treated animals showed near complete and stable recovery within 1 month. Recovery of motor function was associated with restoration of extracellular DA levels as assessed by online microdialysis. Histological analysis showed robust transgene expression not only in the striatum but also in overlying cortical areas. In globus pallidus, we noted loss of NeuN staining, which might be due to different sensitivity in neuronal populations to transgene expression. Taken together, we present a single AAV vector design that result in efficient DOPA production and wide-spread transduction. This is a favorable starting point for continued translation toward a therapeutic application, although future studies need to carefully review target region, vector spread and dilution with this approach.
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Dependovirus/genética , Dihidroxifenilalanina/biosíntesis , GTP Ciclohidrolasa/genética , Vectores Genéticos , Enfermedad de Parkinson/terapia , Tirosina 3-Monooxigenasa/genética , Animales , Cuerpo Estriado/metabolismo , Femenino , GTP Ciclohidrolasa/biosíntesis , GTP Ciclohidrolasa/metabolismo , Técnicas de Transferencia de Gen , Terapia Genética , Enfermedad de Parkinson/metabolismo , Ratas , Ratas Sprague-Dawley , Tirosina 3-Monooxigenasa/biosíntesis , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
L-DOPA is currently the standard treatment for alleviating the motor symptoms in Parkinson's disease. The therapeutic efficacy, however, diminishes as the disease progresses. It has been suggested that the beneficial effect of L-DOPA could be reestablished by changing the mode of administration. Indeed, continuous delivery of l-DOPA has been shown to be an effective way to circumvent many of the side effects seen with traditional oral administration, which results in an intermittent supply of the dopamine precursor to the brain. However, all currently tested continuous dopaminergic stimulation approaches rely on peripheral administration. This is not ideal since it gives rise to off target effects and is difficult to maintain long-term. Thus, there is an unmet need for an effective continuous administration method with an acceptable side effect profile. Viral-mediated gene therapy is a promising alternative paradigm that can meet this demand. Encouraging preclinical studies in animal models of Parkinson's disease showed therapeutic efficacy after expression of the genes encoding the enzymes required for biosynthesis of dopamine. Although the first phase I clinical trials using these approaches have been conducted, clear positive data in placebo controlled efficacy studies is still lacking. We are now at a critical junction and need to carefully review the preclinical data from the clinical translation perspective and identify the key factors that will determine the potential for success in gene therapy for Parkinson's disease.
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Dihidroxifenilalanina/genética , Dihidroxifenilalanina/metabolismo , Terapia Genética/métodos , Enfermedad de Parkinson/terapia , Animales , Antiparkinsonianos/efectos adversos , Antiparkinsonianos/uso terapéutico , Descarboxilasas de Aminoácido-L-Aromático/genética , Química Encefálica/genética , Dependovirus/genética , Dihidroxifenilalanina/biosíntesis , Sistemas de Liberación de Medicamentos , Terapia Genética/efectos adversos , Vectores Genéticos , Humanos , Levodopa/efectos adversos , Levodopa/uso terapéutico , Tirosina 3-Monooxigenasa/genéticaRESUMEN
Drug-induced dyskinesias in dopamine-denervated animals are known to depend on both pre- and postsynaptic changes of the nigrostriatal circuitry. In lesion models used thus far, changes occur in both of these compartments and, therefore, it has not been possible to dissect the individual contribution of each compartment in the pathophysiology of dyskinesias. Here we silenced the nigrostriatal dopamine neurotransmission without affecting the anatomical integrity of the presynaptic terminals using a short-hairpin RNA-mediated knockdown of tyrosine hydroxylase enzyme (shTH). This treatment resulted in significant reduction (by about 70%) in extracellular dopamine concentration in the striatum as measured by on-line microdialysis. Under these conditions, the animals remained nondyskinetic after chronic L-DOPA treatment, whereas partial intrastriatal 6-hydoxydopamine lesioned rats with comparable reduction in extracellular dopamine levels developed dyskinesias. On the other hand, apomorphine caused moderate to severe dyskinesias in both groups. Importantly, single-dose L-DOPA challenge in apomorphine-primed shTH animals failed to activate the already established abnormal postsynaptic responses. Taken together, these data provide direct evidence that the status of the presynaptic, DA releasing compartment is a critical determinant of both the induction and maintenance of L-DOPA-induced dyskinesias.
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Dopamina/metabolismo , Discinesia Inducida por Medicamentos/metabolismo , Terminales Presinápticos/metabolismo , Animales , Apomorfina/farmacología , Cromatografía Líquida de Alta Presión , Dependovirus/genética , Susceptibilidad a Enfermedades , Regulación hacia Abajo/efectos de los fármacos , Discinesia Inducida por Medicamentos/patología , Femenino , Técnicas de Silenciamiento del Gen , Levodopa , Microdiálisis , Neostriado/efectos de los fármacos , Neostriado/metabolismo , Neuronas/efectos de los fármacos , Neuronas/enzimología , Terminales Presinápticos/efectos de los fármacos , Proteínas Proto-Oncogénicas c-fos/metabolismo , ARN Interferente Pequeño/metabolismo , Ratas , Ratas Sprague-Dawley , Recombinación Genética/genética , Sustancia Negra/efectos de los fármacos , Sustancia Negra/enzimología , Factores de Tiempo , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Short-hairpin RNA (shRNA)-mediated gene knockdown is a powerful tool for targeted gene silencing and an emerging novel therapeutic strategy. Recent publications, however, reported unexpected toxicity after utilizing viral-mediated shRNA knockdown in vivo. Thus, it is currently unclear whether shRNA-mediated knockdown strategy can be used as a safe and efficient tool for gene silencing. In this study, we have generated rAAV vectors expressing shRNAs targeting the rat tyrosine hydroxylase (TH) mRNA (shTH) for testing the efficacy of in vivo TH knockdown in the nigral dopaminergic neurons. At high titers, not only the shTH vectors but also the scrambled and green fluorescence protein (GFP)-only controls caused cell death. In a dose-response study, we identified a dose window leading to >60% decrease in TH(+) neurons without any change in vesicular monoamine transporter-2 (VMAT2) expression. Moreover, using the safe and efficient dose, we showed that dopamine (DA) synthesis rate was significantly reduced and this lead to emergence of motor deficits in the shTH-expressing rats. Interestingly, these animals showed very robust and long-lasting recovery after a single systemic L-3,4-dihydroxyphenylalanine (L-DOPA) administration beyond what can be achieved in 6-hydroxydopamine (6-OHDA)-lesioned rats. Our results have implications for both mechanistic and therapeutic studies utilizing long-term shRNA-mediated gene silencing in the nigrostriatal projection system.
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Adenoviridae/genética , Neuronas/metabolismo , Interferencia de ARN/fisiología , Sustancia Negra/citología , Animales , Línea Celular , Cromatografía Líquida de Alta Presión , Dopamina/metabolismo , Femenino , Silenciador del Gen/fisiología , Vectores Genéticos/genética , Humanos , Levodopa , Ratas , Ratas Sprague-Dawley , Tirosina 3-Monooxigenasa/genética , Tirosina 3-Monooxigenasa/metabolismo , Tirosina 3-Monooxigenasa/fisiologíaRESUMEN
Although Parkinson's disease is a movement disorder, in many patients cognitive dysfunction is an important clinical sign. It is not yet clear whether this is attributable solely to a decrease in dopamine levels, or whether other neurotransmitter systems might be involved as well. In the present study, the importance of the mesocorticolimbic dopamine pathway and a possible convergence with forebrain cholinergic projections to neocortex and hippocampus in the regulation of learning and memory abilities were investigated by using specific lesion paradigms in one or both systems. Lesioning of dopaminergic neurons in the ventral tegmental area resulted in an impaired performance in the reference memory task, whereas the execution of the working memory tasks appeared to be unaffected in the Morris water maze. Analysis of the swim paths revealed that the dopamine-depleted animals were capable of adapting a search strategy on a given testing day but failed to transfer this information to the next day, suggesting a deficit in information storage and/or recall. In contrast, cholinergic lesions alone were without effect in all test paradigms. However, when both dopamine and acetylcholine were depleted, animals were also impaired in the working memory task, indicating that a functional convergence of the inputs from these systems was critical for acquisition of spatial memory. Interestingly, such an additional acquisition deficit appeared only after hippocampal cholinergic depletion regardless of a concurrent disruption of basalo cortical cholinergic afferents. Thus, further analyses of cholinergic alterations may prove useful in better understanding the cognitive symptoms in Parkinson's disease.
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Fibras Colinérgicas/fisiología , Dopamina/fisiología , Hipocampo/fisiología , Memoria/fisiología , Animales , Femenino , Aprendizaje por Laberinto/fisiología , Degeneración Nerviosa/fisiopatología , Vías Nerviosas/fisiología , Ratas , Ratas Sprague-DawleyRESUMEN
The presence of focal EEG abnormalities in juvenile absence syndrome (JAS) may cause it to be misdiagnosed as focal epilepsy. The purpose of our study was to determine the presence of focal EEG abnormalities in patients with JAS and to ascertain whether some clinical features or antiepileptic drugs (AEDs) have an effect on focality. Serial EEGs of 52 consecutive patients with JAS were retrospectively analyzed. The patients were divided into two groups according to whether they were treated with valproic acid and/or lamotrigine (VA-LTG) or not during the times of these EEG recordings. The relationship between the presence of EEG focality and the use of AEDs in addition to other risk factors was examined. Two or three consecutive EEGs (total 100) of the 52 patients were evaluated. Among these, the rates of focal EEG abnormalities were 18%, 36%, and 25% during the follow-up EEGs without AEDs (5/27) and first (16/45) and second EEGs (7/28) with AEDs, respectively. The last two EEGs showed a tendency towards a higher proportion of EEG focality in patients who received other AEDs (47%-45%) compared with those that received VA-LTG (13%-12%). The proportion of JAS patients with focal EEG findings in serial EEGs tended to decrease with an increasing rate of VA-LTG use. As a hypothetical explanation, changes in EEG focality may reflect the effect of AEDs other than VA and/or LTG, in addition to a developing hyperexcitable cortical area.
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Anticonvulsivantes/uso terapéutico , Electroencefalografía , Epilepsia Tipo Ausencia/tratamiento farmacológico , Epilepsia Tipo Ausencia/fisiopatología , Adolescente , Niño , Femenino , Humanos , Masculino , Estudios Retrospectivos , Factores de Riesgo , Resultado del TratamientoRESUMEN
A 44-year-old male presented with multiple punctate acute infarcts of the vertebrobasilar circulation and a computed tomographic angiogram showing stenosis of the right vertebral origin. A digital subtraction angiogram demonstrated a new intraluminal filling defect at the origin of the stenotic vertebral artery where antegrade flow was maintained. This filling defect was accepted to be an acute thrombus of the vertebral origin, most likely due to rupture of a vulnerable plaque. The patient was treated with intravenous heparin. A control angiogram revealed dissolution of the acute thrombus under anticoagulation and the patient was treated with stenting with distal protection. Diffusion-weighted magnetic resonance imaging demonstrated no additional acute ischemic lesions. We were unable to find a similar report in the English literature documenting successful management of an acute vertebral ostial thrombus with anticoagulation. Anticoagulation might be considered prior to endovascular treatment of symptomatic vertebral stenoses complicated by the presence of acute thrombus.
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Trombosis/etiología , Trombosis/terapia , Insuficiencia Vertebrobasilar/complicaciones , Insuficiencia Vertebrobasilar/terapia , Enfermedad Aguda , Adulto , Anticoagulantes/uso terapéutico , Implantación de Prótesis Vascular , Heparina/uso terapéutico , Humanos , Masculino , Stents , Trombosis/tratamiento farmacológicoRESUMEN
Posterior leukoencephalopathy syndrome (PLES) is an acute neurological disorder. The most plausible hypothesis for the pathophysiology of PLES is the loss of autoregulation and consequent vasogenic edema. PLES is mostly attributed to severe or sudden elevations of arterial blood pressure. A number of reports, however, describe patients with PLES without severe hypertension. This report presents two patients with nephrotic syndrome who developed PLES without customarily severe hypertension. Proteinuria, low levels of serum albumin, or generalized increase in capillary permeability in nephrotic syndrome can initiate PLES with moderately high arterial blood pressure levels. PLES is increasingly recognized by neurologists, but it should also be remembered by internists when confronted with patients with nephrotic syndrome who present with neurological symptoms, whether or not they have severe hypertension.
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Encefalopatías/etiología , Síndrome Nefrótico/complicaciones , Adulto , Femenino , Humanos , Hipertensión/complicaciones , Persona de Mediana EdadRESUMEN
Primary angiitis of the CNS is histopathologically characterized by ischemic lesions and small petechial hemorrhages. Unlike CT or conventional MR imaging, gradient-echo MR imaging depicts these chronic petechial hemorrhages. We herein report the case of biopsy-proved primary angiitis of the CNS in a 42-year-old man; whom gradient-echo MR imaging revealed multiple petechial hemorrhages in the cortical-subcortical brain regions. The identification of petechial hemorrhages by gradient-echo MR imaging promises to be a valuable surrogate marker supporting the diagnosis of primary angiitis of the CNS.