91 resultados para pallidus


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To analyze the differential recruitment of the raphe nuclei during different phases of feeding behavior, rats were subjected to a food restriction schedule (food for 2 h/day, during 15 days). The animals were submitted to different feeding conditions, constituting the experimental groups: search for food (MFS), food ingestion (MFI), satiety (MFSa) and food restriction control (MFC). A baseline condition (BC) group was included as further control. The MFI and MFC groups, which presented greater autonomic and somatic activation, had more FOS-immunoreactive (FOS-IR) neurons. The MFI group presented more labeled cells in the linear (LRN) and dorsal (DRN) nuclei; the MFC group showed more labeling in the median (MRN), pontine (PRN), magnus (NRM) and obscurus (NRO) nuclei; and the MFSa group had more labeled cells in the pallidus (NRP). The BC exhibited the lowest number of reactive cells. The PRN presented the highest percentage of activation in the raphe while the DRN the lowest. Additional experiments revealed few double-labeled (FOS-IR+ 5-HT-IR) cells within the raphe nuclei in the MFI group, suggesting little serotonergic activation in the raphe during food ingestion. These findings suggest a differential recruitment of raphe nuclei during various phases of feeding behavior. Such findings may reflect changes in behavioral state (e.g., food-induced arousal versus sleep) that lead to greater motor activation, and consequently increased FOS expression. While these data are consistent with the idea that the raphe system acts as gain setter for autonomic and somatic activities, the functional complexity of the raphe is not completely understood. (c) 2008 Elsevier B.V. All rights reserved.

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INTRODUCTION: Postural instability is a major source of disability in idiopathic Parkinson's disease (IPD). Deep brain stimulation of the globus pallidus internus (GPI-DBS) improves clinician-rated balance control but there have been few quantitative studies of its interactive effects with levodopa (L-DOPA). The purpose of this study was to compare the short-term and interactive effects of GPI-DBS and L-DOPA on objective measures of postural stability in patients with longstanding IPD. METHODS: Static and dynamic posturography during a whole-body leaning task were performed in 10 IPD patients with bilateral GPI stimulators under the following conditions: untreated (OFF); L-DOPA alone; DBS alone; DBS+L-DOPA, and in 9 healthy Control subjects. Clinical status was assessed using the UPDRS and AIMS Dyskinesia Scale. RESULTS: Static sway was greater in IPD patients in the OFF state compared to the Control subjects and was further increased by L-DOPA and reduced by GPI-DBS. In the dynamic task, L-DOPA had a greater effect than GPI-DBS on improving Start Time, but reduced the spatial accuracy and directional control of the task. When the two therapies were combined, GPI-DBS prevented the L-DOPA induced increase in static sway and improved the accuracy of the dynamic task. CONCLUSION: The findings demonstrate GPI-DBS and L-DOPA have differential effects on temporal and spatial aspects of postural control in IPD and that GPI-DBS counteracts some of the adverse effects of L-DOPA. Further studies on larger numbers of patients with GPI stimulators are required to confirm these findings and to clarify the contribution of dyskinesias to impaired dynamic postural control.

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Com a intenção de conhecer a identidade e a diversidade da araneofauna relacionada com a cultura do arroz e as áreas entorno da lavoura, foi realizado um inventário, na Estação Experimental do Arroz (EEA), do Instituto Rio Grandense do Arroz (IRGA), Cachoeirinha, RS (50o58’21’’W; 29o55’30’’S), procurando contribuir com o conhecimento deste agroecossistema. Procurou-se avaliar a riqueza de espécies, abundância e similaridade da fauna de aranhas entre as formações e períodos escolhidos para a amostragem. Foram realizadas saídas de 20/10/2004 a 6/6/2005; o local de estudo (EEA) foi dividido em três áreas; a primeira um campo, que durante muitos anos foi utilizado para o cultivo do arroz, mas atualmente está “desativado” (em pousio), a segunda área a lavoura de arroz, subdividida em duas subáreas (arroz 1 e 2), e por fim, a terceira área na borda de um fragmento de mata próximo ao campo. Em cada área foram efetuadas coletas em transectos, dois em cada área, totalizando oito a cada coleta. Nos transectos foram realizadas coletas matinais utilizando a metodologia de rede de varredura (35 cm de diâmetro), para amostrar a araneofauna da vegetação herbácea e subarbustiva, tanto na cultura do arroz, no campo e na borda da mata. Em cada transecto foram efetuados 50 golpes com a rede em movimentos de avanço pendulares. Três períodos foram avaliados: antes do arroz ser semeado, durante o desenvolvimento do arroz e após a colheita. Foram coletadas um total de 2717 aranhas, incluindo jovens e adultos. A partir do exame de todas as amostragens realizadas, houve uma maior abundância de aranhas no campo, diferindo significativamente das outras áreas. A comunidade de aranhas das áreas estudadas constitui-se de 85 morfoespécies, pertencentes a 15 famílias, predominando, no geral, Oxyopidae, Araneidae e Tetragnathidae; no campo e borda ocorreu predomínio de Oxyopidae e no arroz (1 e 2) foi Araneidae. O grupo funcional com maior abundância de aranhas, que prevaleceu em todas as áreas, foi das caçadoras emboscadoras, seguido das construtoras de teias orbiculares. Entre as morfoespécies as mais abundantes foram: Oxyopes salticus Hentz, 1845, Alpaida veniliae (Keyserling, 1865) e Misumenops pallidus (Keyserling, 1880). A família que registrou o maior número de morfoespécies foi Linyphiidae. A única morfoespécie registrada em todos os períodos amostrais foi Oxyopes salticus, sendo a mais abundante no campo e borda; no arroz foi Alpaida veniliae. A maioria das morfoespécies foram raras, ocorrendo em somente uma ou duas coletas. Dos estimadores de riqueza de espécies o que mais se aproximou da riqueza observada foi Bootstrap nas áreas de campo (estimando 30,55 espécies; 85,1% das espécies amostradas), arroz 1 (31,41; 82,8%) e borda (79,02; 78,5%); no arroz 2 foi Chao 1 (39; 82,1%). Abundância e riqueza foram significativamente diferentes entre as áreas e os períodos. Ocorreu predomínio expressivo de aranhas jovens (imaturas). Entre as aranhas adultas, não existiu diferença significativa nos tamanhos médios entre as espécies das diferentes áreas. Dos fatores abióticos, somente a temperatura teve relação com a maior abundância na borda. Houve diferença significativa para a similaridade entre as áreas e os períodos. São apresentados aspectos da fenologia das morfoespécies mais abundantes registradas nesta pesquisa e outros resultados encontrados sugerem a importância de estudos da biodiversidade nos agroecossistemas.

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Espécies de artrópodos entomófagos foram coletadas e identificadas nos genótipos sorgo AF-28, IAC-83/75-5-1-6, TX-2536, BR-300, IPA-201 e SAR, no Município de Selvíria, MS. Foram conduzidos três experimentos em campo, com os genótipos sendo semeados em 03/1988, 10/1988 e 02/1989, respectivamente. Para contagem dos artrópodos entomófagos, no início do florescimento foram marcadas 560 panículas por genótipo. Após esse momento, diariamente e durante 14 dias seguidos, foram coletadas 40 panículas por genótipo (10 por parcela). Nas coletas foram utilizados sacos plásticos com 10 litros de capacidade para envolver as panículas e capturar os artrópodos presentes. As panículas coletadas foram levadas para o Laboratório de Entomologia da Faculdade de Engenharia/UNESP, Campus de Ilha Solteira, SP, para separação, contagem e identificação dos artrópodos. Nas panículas provenientes da semeadura da seca coletou-se, em média, maior número de artrópodos entomófagos em relação à semeadura das águas. Dos artrópodos entomófagos coletados, as aranhas apresentaram maior número de espécies e, desses, a tecelã Alpaida veniliae (Keys.), a aranha corredora noturna Cheiracanthium inclusum (Blackwall), e a caçadora de emboscada, Misumenops pallidus (Keys.), foram as mais abundantes. O genótipo de sorgo IPA-201 comportou-se como o mais atrativo ao percevejo Orius sp. e à tesourinha Doru lineare (Eschs.), enquanto que o IAC-83/75-5-1-6 foi medianamente atrativo a D. lineare. As aranhas foram coletadas em maior número nos genótipos BR-300 e SART.

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Fungi of the family Nidulariaceae or bird s nest fungi present a vase-shaped basidiomata with the wall surface smooth or striated lengthwise and internal structures resembling small bird eggs in a nest, the peridioles. Among the five genera that comprise the group, the more representative is Cyathus Haller: Pers. The Brazilian Northeast region shows major importance for the world s diversity by containing a Brazilian unique and exclusively phytoecological domain, the Caatinga, which lacks particular attention regarding macrofungi. Although the gradual growth of knowledge in recent years, studies are still insipient in the Caatinga domain. Between their various vegetal formations are the Brejos de Altitude , described as islands with moist perennial vegetation, low soil fertility and annual precipitation of 900 1.300 mm. This study aimed to evaluate the taxonomic richness of Nidulariaceae fungi in Caatinga s areas of Northeastern Brazil, describing and identifying species, as well as expanding the collection of Herbarium UFRN Fungos. For description of Nidulariaceae fungi was followed the proposed by specialized literature in the group. We have found and described 10 species of the genus Cyathus, namely: C. earlei Lloyd, C. gayanus Tul. & C. Tul., C. gracilis H.J. Brodie, C. intermedius (Mont.) Tul. & C. Tul., C. limbatus Tul. & C. Tul., C. montagnei Tul. & C. Tul., C. pallidus Berk. & M.A. Curtis, C. poeppigii Tul. & C. Tul., C. striatus (Huds.) Willd. and C. tríplex Lloyd. Beyond these have been described four new species to science: Cyathus calvescens R. Cruz & Baseia sp. nov., C. hortum R. Cruz & Baseia sp. nov., C. magnomuralis R. Cruz & Baseia sp. nov. and C. parvocinereus R. Cruz & Baseia sp. nov. Two samples were identified only to genus level. No member of Mycocalia J.T. Palmer, Nidula V.S. White, Nidularia Fr. and Crucibulum Tul. & C. Tul. has been found, however the results were extremely valuable for being an unprecedented work in Caatinga, and importante tool for implementation of conservation projects and sustainable utilization of this domain

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Background: Thalamotomies and pallidotomies were commonly performed before the deep brain stimulation (DBS) era. Although ablative procedures can lead to significant dystonia improvement, longer periods of analysis reveal disease progression and functional deterioration. Today, the same patients seek additional treatment possibilities. Methods: Four patients with generalized dystonia who previously had undergone bilateral pallidotomy came to our service seeking additional treatment because of dystonic symptom progression. Bilateral subthalamic nucleus DBS (B-STN-DBS) was the treatment of choice. The patients were evaluated with the BurkeFahnMarsden Dystonia Rating Scale (BFMDRS) and the Unified Dystonia Rating Scale (UDRS) before and 2 years after surgery. Results: All patients showed significant functional improvement, averaging 65.3% in BFMDRS (P = .014) and 69.2% in UDRS (P = .025). Conclusions: These results suggest that B-STN-DBS may be an interesting treatment option for generalized dystonia, even for patients who have already undergone bilateral pallidotomy. (c) 2012 Movement Disorder Society

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The endocannabinoid system has been implicated in several neurobiological processes, including neurodegeneration, neuroprotection and neuronal plasticity. The CB1 cannabinoid receptors are abundantly expressed in the basal ganglia, the circuitry that is mostly affected in Parkinson’s Disease (PD). Some studies show variation of CB1 expression in basal ganglia in different animal models of PD, however the results are quite controversial, due to the differences in the procedures employed to induce the parkinsonism and the periods analyzed after the lesion. The present study evaluated the CB1 expression in four basal ganglia structures, namely striatum, external globus pallidus (EGP), internal globus pallidus (IGP) and substantia nigra pars reticulata (SNpr) of rats 1, 5, 10, 20, and 60 days after unilateral intrastriatal 6-hydroxydopamine injections, that causes retrograde dopaminergic degeneration. We also investigated tyrosine hydroxylase (TH), parvalbumin, calbindin and glutamic acid decarboxylase (GAD) expression to verify the status of dopaminergic and GABAergic systems. We observed a structure-specific modulation of CB1 expression at different periods after lesions. In general, there were no changes in the striatum, decreased CB1 in IGP and SNpr and increased CB1 in EGP, but this increase was not sustained over time. No changes in GAD and parvalbumin expression were observed in basal ganglia, whereas TH levels were decreased and the calbindin increased in striatum in short periods after lesion. We believe that the structure-specific variation of CB1 in basal ganglia in the 6-hydroxydopamine PD model could be related to a compensatory process involving the GABAergic transmission, which is impaired due to the lack of dopamine. Our data, therefore, suggest that the changes of CB1 and calbindin expression may represent a plasticity process in this PD model

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Surgery for Parkinson's Disease (PD) is being increasingly used. The main reason for this renewal in surgical treatment for PD is the "deep brain stimulation" (DBS) that replaced the previously used stereotactic lesions in most centers. DBS allows a focal specific electrical stimulation of basal ganglia target instead of an irreversible lesion. Mainly bilateral DBS of the nucleus subthalamicus is now an established surgical treatment for PD. But DBS of the Globus pallidus internus and of the thalamus should still be considered in selected patients. DBS is an efficient treatment for motor complication of PD that can no longer be controlled by drug treatment. Dyskinesia, bradykinesia, tremor and rigor can be improved by DBS and the medication can be reduced. It is still unclear, however, how the improvement in motor symptoms affects quality of life in the long term. Furthermore, patients with severe cognitive and psychiatric symptoms as well as patients with severe axial symptoms should not be operated since these symptoms may worsen after surgery.

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OBJECT: The goal of this study was to investigate the efficacy of long-term deep brain stimulation (DBS) of the posteroventral lateral globus pallidus internus (GPi) accomplished using a single-contact monopolar electrode in patients with advanced Parkinson disease (PD). METHODS: Sixteen patients suffering from severe PD and levodopa-induced side effects such as dyskinesias and on-off fluctuations were enrolled in a prospective study protocol. There were six women and 10 men and their mean age at surgery was 65 years. All patients underwent implantation of a monopolar electrode in the posteroventral lateral GPi. Initially, nine patients received unilateral stimulation. Three of these patients underwent contralateral surgery at a later time. Ten patients received bilateral stimulation (contemporaneous bilateral surgery was performed in seven patients and staged bilateral surgery in the three patients who had received unilateral stimulation initially). Formal assessments were performed during both off-medication and on-medication (levodopa) periods preoperatively, and at 3 and 12 months postoperatively. There were no serious complications related to surgery or to DBS. Two transient adverse events occurred: in one patient a small pallidal hematoma developed, resulting in a prolonged micropallidotomy effect, and in another patient a subcutaneous hemorrhage occurred at the site of the pacemaker. In patients who received unilateral DBS, the Unified Parkinson's Disease Rating Scale activities of daily living (ADL) score during the off-levodopa period decreased from 30.8 at baseline to 20.4 at 3 months (34% improvement) and 20.6 at 12 months (33% improvement) postoperatively. The motor score during the off period improved from 57.2 at baseline to 35.2 at 3 months (38% improvement) and 35.3 at 12 months (38% improvement) postoperatively. Bilateral DBS resulted in a reduction in the ADL score during the off period from 34.9 at baseline to 22.3 at 3 months (36% improvement) and 22.9 at 12 months (34% improvement). The motor score for the off period changed from 63.4 at baseline to 40.3 at 3 months (36% improvement) and 37.5 at 12 months (41% improvement). In addition, there were significant improvements in patients' symptoms during the on period and in on-off motor fluctuations. CONCLUSIONS: Pallidal DBS accomplished using a monopolar electrode is a safe and effective procedure for treatment of advanced PD. Compared with pallidotomy, the advantages of pallidal DBS lie in its reversibility and the option to perform bilateral surgery in one session. Comparative studies in which DBS is applied to other targets are needed.

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DJ-1 is mutated in autosomal recessive, early onset Parkinson's disease but the exact localization of the DJ-1 gene product in the mammalian brain is largely unknown. We aimed to evaluate the DJ-1 mRNA expression pattern in the mouse brain. Serial coronal sections of brains of five male and five female adult mice were investigated by using in situ hybridization with a DJ-1 specific 35S-labeled oligonucleotide probe. Hybridized sections were analyzed after exposure to autoradiography films and after coating with a photographic emulsion. DJ-1 was heterogeneously expressed throughout the mouse central nervous system. A high expression of DJ-1 mRNA was detected in neuronal and non-neuronal populations of several structures of the motor system such as the substantia nigra, the red nucleus, the caudate putamen, the globus pallidus, and the deep nuclei of the cerebellum. Furthermore, DJ-1 mRNA was also highly expressed in non-motor structures including the hippocampus, the olfactory bulb, the reticular nucleus of the thalamus, and the piriform cortex. The high expression of DJ-1 mRNA in brain regions involved in motor control is compatible with the occurrence of parkinsonian symptoms after DJ-1 mutations. However, expression in other regions indicates that a dysfunction of DJ-1 may contribute to additional clinical features in patients with a DJ-1 mutation.

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In the laboratory of Dr. Dieter Jaeger at Emory University, we use computer simulations to study how the biophysical properties of neurons—including their three-dimensional structure, passive membrane resistance and capacitance, and active membrane conductances generated by ion channels—affect the way that the neurons transfer synaptic inputs into the action potential streams that represent their output. Because our ultimate goal is to understand how neurons process and relay information in a living animal, we try to make our computer simulations as realistic as possible. As such, the computer models reflect the detailed morphology and all of the ion channels known to exist in the particular neuron types being simulated, and the model neurons are tested with synaptic input patterns that are intended to approximate the inputs that real neurons receive in vivo. The purpose of this workshop tutorial was to explain what we mean by ‘in vivo-like’ synaptic input patterns, and how we introduce these input patterns into our computer simulations using the freely available GENESIS software package (http://www.genesis-sim.org/GENESIS). The presentation was divided into four sections: first, an explanation of what we are talking about when we refer to in vivo-like synaptic input patterns

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Spasmodic dysphonia is a neurological disorder characterized by involuntary spasms in the laryngeal muscles during speech production. Although the clinical symptoms are well characterized, the pathophysiology of this voice disorder is unknown. We describe here, for the first time to our knowledge, disorder-specific brain abnormalities in these patients as determined by a combined approach of diffusion tensor imaging (DTI) and postmortem histopathology. We used DTI to identify brain changes and to target those brain regions for neuropathological examination. DTI showed right-sided decrease of fractional anisotropy in the genu of the internal capsule and bilateral increase of overall water diffusivity in the white matter along the corticobulbar/corticospinal tract in 20 spasmodic dysphonia patients compared to 20 healthy subjects. In addition, water diffusivity was bilaterally increased in the lentiform nucleus, ventral thalamus and cerebellar white and grey matter in the patients. These brain changes were substantiated with focal histopathological abnormalities presented as a loss of axonal density and myelin content in the right genu of the internal capsule and clusters of mineral depositions, containing calcium, phosphorus and iron, in the parenchyma and vessel walls of the posterior limb of the internal capsule, putamen, globus pallidus and cerebellum in the postmortem brain tissue from one patient compared to three controls. The specificity of these brain abnormalities is confirmed by their localization, limited only to the corticobulbar/corticospinal tract and its main input/output structures. We also found positive correlation between the diffusivity changes and clinical symptoms of spasmodic dysphonia (r = 0.509, P = 0.037). These brain abnormalities may alter the central control of voluntary voice production and, therefore, may underlie the pathophysiology of this disorder.

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A micro-electrospray interface was developed specifically for the neurobiological applications described in this dissertation. Incorporation of a unique nano-flow liquid chromatography micro-electrospray "needle" into the micro-electrospray interface (micro-ES/MS) increased the sensitivity of the mass spectrometric assay by $\sim$1000 fold and thus permitted the first analysis of specific neuroactive compounds in brain extracellular fluid collected by in vivo microdialysis (Md).^ Initial in vivo data presented deals with the pharmacodynamics of a novel GABA$\sb{\rm B}$ antagonist and the availability of the compound in its parent (unmetabolized) form to the brain of the anesthetized rat. Next, the first structurally specific endogenous release of (Met) $\sp5$-enkephalin was demonstrated in unanesthetized freely-moving animals (release of $\sim$6.5 fmole of (Met) $\sp5$-enkephalin into the dialysate by direct neuronal depolarization). The Md/micro-ES/MS system was used to test the acute effects of drugs of abuse on the endogenous release of (Met) $\sp5$-enkephalin from the globus pallidus/ventral pallidum brain region in rats. Four drugs known to be abused by man (morphine, cocaine, methamphetamine and diazepam) were tested. Morphine and cocaine both elicited a two-fold or more increase in the release of (Met) $\sp5$-enkephalin over vehicle controls. Diazepam elicited a small decrease in (Met) $\sp5$-enkephalin levels and methamphetamine showed no significant effect on (Met) $\sp5$-enkephalin. These results imply that (Met) $\sp5$-enkephalin may be involved in the reward pathway of certain drugs of abuse. ^

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INTRODUCTION Neurogenic bladder dysfunction is well described in Parkinson's disease and has a major impact on quality of live. In contrast, little is known about the extent of urinary symptoms in other movement disorders such as dystonia and about the role of the basal ganglia in bladder control.. PATIENTS AND METHODS A consecutive series of 11 patients with severe dystonia undergoing deep brain stimulation (DBS) of the globus pallidus internus was prospectively enrolled. Bladder function was assessed by the International Prostate Symptom Score and urodynamic investigation (UDI) before DBS surgery and afterwards in the conditions with and without DBS. RESULTS In UDI before DBS surgery, detrusor overactivity was found in 36% (4/11) of dystonia patients. With pallidal DBS ON, maximum flow rate significantly decreased, post-void residual significantly increased and detrusor overactivity disappeared.. CONCLUSIONS Pathological urodynamic changes can be found in a relevant percentage of dystonia patients. Pallidal DBS has a relaxing effect on detrusor function indicating a role of the basal ganglia in lower urinary tract control. Thus, a better understanding on how subcortical networks influence lower urinary tract function might open new therapeutic perspectives..