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Differential response of AMPA and NMDA glutamate receptors of Purkinje cells to aging of the chicken cerebellum

PIRES, Raquel S.; REAL, Caroline C.; FOLADOR, Thiago S.; TELLINI, Nataly R.; TORRAO, Andrea S.; BRITTO, Luiz R. G.
Fonte: ELSEVIER IRELAND LTD Publicador: ELSEVIER IRELAND LTD
Tipo: Artigo de Revista Científica
ENG
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Aging can lead to cognitive, affective, learning, memory and motor deficits. Since the cerebellum and glutamatergic neurotransmission are involved in several of those functions, the present work aimed at studying the expression of AMPA and NMDA glutamate receptor subunits in the chick cerebellum during aging. Young (30 days old) and aged (ca. 4 years old) chickens (Gallus gallus) were used in order to evaluate the expression of GluR1, GluR2/3 and NR1 subunits. The cerebella of young and aged chickens were subjected to immunohistochemical and immunoblotting techniques. Numbers of GluR1, GluR2/3 and NR1-positive cells and optical density of the immunoblotting data were analyzed and submitted to statistical analysis using ANOVA and the Bonferroni post hoc test. Mean density of Purkinje cells stained for Giemsa, GluR1, GluR2/3 and NR1 in the cerebellum all showed a statistically significant decrease in aged animals when compared to the young animals (Giemsa, P < 0.01; GluRs and NR1, P < 0.03). However, the ratio of GluR1 and GluR2/3-positive Purkinje cells in relation the total number of Purkinje cells found in each time point decreased with aging (ca. 10%), whereas the ratio of NR1-positive cells increased (ca. 9%). The immunoblotting data showed a significant decrease of GluR1 (ca. 66%) and GluR2/3 (ca. 55%) protein expression with aging...

Ontogênese de conexinas no cerebelo.; Ontogenesis of connexins in the cerebellum.

Guedes, Vivian de Alvarenga
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 27/07/2012 PT
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As junções comunicantes formadas por conexinas (Cx) ligam o citoplasma de células adjacentes e permitem a passagem de moléculas e íons entre elas. No sistema nervoso, esses canais constituem as sinapses elétricas e são fundamentais para a fisiologia glial. No desenvolvimento, as conexinas estão envolvidas nos processos de migração, proliferação e diferenciação celular. Caracterizamos a expressão gênica (RNAm) e protéica de duas importantes conexinas no cerebelo de aves: Cx36 (neuronal) e Cx43 (glial). Houve um aumento protéico e na expressão de RNAm tanto para a Cx36 quanto para a Cx43. Para a Cx43 esse aumento foi associado a sinaptogênese. A Cx36 foi observada em estágios mais precoces, na camada proliferativa cerebelar. No cerebelo pós-natal, A Cx36 foi observada nos dendritos das células de Golgi. A Cx43 encontra-se principalmente em astrócitos da camada granular e substância branca. Em conclusão, nós observamos uma padrão de expressão espaço-temporal distinto entre as duas conexinas, relacionado a papéis específicos na função de desenvolvimento cerebelares.; Gap junction channels composed of connexins (Cxs) connect the cytoplasm of adjacent cells and allow the flow of ions and molecules between them. In the nervous system...

Efeitos da mal nutrição protéica sobre o metabolismo da glicina em cerebelo de ratos durante o seu desenvolvimento; Study of developmental effects of protein malnutrition on glycine metabolism in cerebellum of rats

Souza, Karine Bresolin de
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
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Malnutrition is a worldwide problem affecting millions of unborn and young children during the most vulnerable stages of brain development (1). All restriction of protein during the perinatal period of life can alter the development of mammalian fetus and have marked repercussions on development of the Central Nervous System (CNS). The brain is vulnerable to protein malnutrition with altered morphologic and biochemical maturation, leading to impaired functions. The focus of this study is to investigate [U-14C]glycine metabolism in malnourished rats submitted to pre- and postnatal protein deprivation (diet: 8% protein with addition and without addition of L-methionine) on glycine metabolism of rats (normonourished group: 25% protein). It was observed that protein malnutrition alters oxidation to CO2, conversion to lipids and protein synthesis from [U-14C]glycine in cerebellum of malnourished rats without addition of L-methionine on a diet at 7 and 21 days of postnatal life. Our results also indicate that protein malnutrition causes a retardation in the normally ordered progression of brain development, and the malnourished groups have smaller cells, reduction in cell numbers and smaller cerebellar weight comparing to the control group.; Resumo não disponível.

Insulin concentrations in cerebellum and body balance in diabetic male rats: Aerobic training effects

Arantes, Luciana Mendonça; Bertolini, Natalia Oliveira; de Moura, Rodrigo Ferreira; de Mello, Maria Alice Rostom; Luciano, Eliete
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 58-62
ENG
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36.84%
Brain insulin has had widespread metabolic, neurotrophic, and neuromodulatory functions and has been involved in the central regulation of food intake and body weight, learning and memory, neuronal development, and neuronal apoptosis. Purpose: The present study investigated the role of swimming training on cerebral metabolism on insulin concentrations in cerebellum and the body balance performance of diabetic rats. Methods: Forty Male Wistar rats were divided in four groups: sedentary control (SC), trained control (TC), sedentary diabetic (SD), and trained diabetic (TD). Diabetes was induced by alloxan (32 mg kg b.w.), single dose injection. The mean blood glucose of diabetic groups was 367 ± 40 mg/dl. Training program consisted in swimming 5 days/week, 1 h/day, 8 weeks, supporting a workload corresponding to 90% of maximal lactate steady state (MLSS). For the body balance testing rats were trained to traverse for 5 min daily for 5-7 days. All dependent variables were analyzed by one-way analysis of variance (ANOVA) and a significance level of p < 0.05 was used for all comparisons. Results: The body balance testing scores were different between groups. Insulin concentrations in cerebellum were not different between groups. Conclusion: It was concluded that in diabetic rats...

Interaction of Maternal Separation on the UCh Rat Cerebellum

Oliveira, S. A.; Fontanelli, B. A. F.; Stefanini, M. A.; Chuffa, L. G. A.; Teixeira, G. R.; Lizarte, F. S. N.; Tirapelli, L. F.; Quitete, V. H. A.; Matheus, S. M. M.; Padovani, C. R.; Martinez, M.; Martinez, F. E.
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 44-51
ENG
Relevância na Pesquisa
36.76%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 06/60569-3; Maternal care is the main source of signals and stimuli for proper development, growth, and production of adjustment responses to stressful factors. Adverse experiences in childhood are associated with a vulnerability to developing abusive ethanol ingestion via alterations of the response of the hypothalamic-pituitary-adrenal axis. Alcoholism causes global brain abnormalities, with the cerebellum being one of the most susceptible areas. We evaluated the effect of maternal separation on the cerebellum structure of male UCh rats. Adult male UChA (low 10% ethanol consumption) and UChB (high 10% ethanol consumption) rats were divided in to four experimental groups: (1) UChA, (2) UChA maternal separation (MS), (3) UChB, and (4) UChB MS. The MS occurred between the 4th and 14th days of age, for 240 min day(-1). Euthanasia was performed at 120 days of age. An image analysis system was used to measure cerebellar cortical height and Purkinje cellular area and height in five rats from each group. The cerebellar sections were stained with antibodies against IGFR-I. MS did not alter the ethanol consumption of UChA and UChB rats. Corticosterone level was significantly higher in UChA MS and UChB MS rats than in UChA and UChB rats. The Purkinje cellular area and height were higher in UChA MS rats. IGFR-I expression was observed in the cortical glomerular area of UChA MS and UChB MS rats. MS altered the Purkinje cells in the cerebella of male UCh rats. Microsc. Res. Tech. 77:44-51...

Apoptosis of Purkinje and Granular Cells of the Cerebellum Following Chronic Ethanol Intake

Oliveira, Suelen A.; Chuffa, Luiz Gustavo A.; Fioruci-Fontanelli, Beatriz Aparecida; Lizarte Neto, Fermino Sanches; Novais, Paulo Cezar; Tirapelli, Luiz Fernando; Oishi, Jorge Camargo; Takase, Luiz Fernando; Stefanini, Maira Aparecida; Martinez, Marcelo;
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 728-738
ENG
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36.84%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 11/50466-0; Ethanol alters motricity, learning, cognition, and cellular metabolism in the cerebellum. We evaluated the effect of ethanol on apoptosis in Golgi, Purkinje, and granule cells of the cerebellum in adult rats. There were two groups of 20 rats: a control group that did not consume ethanol and an experimental group of UChA rats that consumed ethanol at 10 % (<2 g ethanol/kg body weight/day). At 120 days old, rats were anesthetized and decapitated, and their cerebella were collected and fixed. Cerebellar sections were subjected to immunohistochemistry for terminal deoxynucleotide transferase dUTP nick end labeling (TUNEL), caspase-3, X-linked inhibitor of apoptosis protein (XIAP), and insulin-like growth factor 1-receptor (IGF-1R); real-time PCR (RT-PCR) to determine caspase-3, XIAP, and IGF-1R gene expression; and transmission electron microscopy (TEM). We identified fragmentation of DNA and an increase in caspase-3 protein and XIAP in Purkinje cells, whereas granule cells exhibited increased caspase-3 and XIAP. IGF-1R expression was unchanged. There was no significant difference in gene expression of caspase-3, XIAP, and IGF-1R. There were an increase in lipid droplets...

Hypomyelination with atrophy of the basal ganglia and cerebellum: case report

Matta,André Palma da Cunha; Ribas,Márcia Cristina Antunes
Fonte: Academia Brasileira de Neurologia - ABNEURO Publicador: Academia Brasileira de Neurologia - ABNEURO
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2007 EN
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Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) is a rare disease that has been recently described. It must be remembered as a possible etiology of leukoencephalopathies in children. We describe a typical case of H-ABC in a 11-month-old boy. He presents with global development delay, oral dyskinesia, and global dystonia and spasticity. Magnetic resonance imaging disclosed typical features of H-ABC and clinical laboratory tests were all negative. A slow neurological deterioration has been detected with worsening of involuntary movements.

Ganglioneuroblastoma of the cerebellum: neuroimaging and pathological features of a case

Gasparetto,Emerson L.; Rosemberg,Sérgio; Matushita,Hamilton; Leite,Claudia da Costa
Fonte: Academia Brasileira de Neurologia - ABNEURO Publicador: Academia Brasileira de Neurologia - ABNEURO
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2007 EN
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OBJECTIVE: To report a case of ganglioneuroblastoma of cerebellum, with emphasis to the neuroimaging and pathological findings. CASE REPORT: A one year and eight-month-old girl presented with a two-month history of hypoactivity and tremor in the legs. The MRI showed an enhancing cerebellar mass hypointense on T1 and hyperintense on T2-weighted images. The patient underwent a craniotomy with resection of the lesion. The histological and immunohistochemical studies defined the diagnosis of ganglioneuroblastoma. CONCLUSION: The MRI findings of our case showed no features which could help in the differentiation between ganglioneuroblastoma and the other common types of posterior fossa neoplasms in the pediatric population.

Cerebellum and psychiatric disorders

Baldaçara,Leonardo; Borgio,João Guilherme Fiorani; Lacerda,Acioly Luiz Tavares de; Jackowski,Andrea Parolin
Fonte: Associação Brasileira de Psiquiatria - ABP Publicador: Associação Brasileira de Psiquiatria - ABP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2008 EN
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OBJECTIVE: The objective of this update article is to report structural and functional neuroimaging studies exploring the potential role of cerebellum in the pathophysiology of psychiatric disorders. METHOD: A non-systematic literature review was conducted by means of Medline using the following terms as a parameter: "cerebellum", "cerebellar vermis", "schizophrenia", "bipolar disorder", "depression", "anxiety disorders", "dementia" and "attention deficit hyperactivity disorder". The electronic search was done up to April 2008. DISCUSSION: Structural and functional cerebellar abnormalities have been reported in many psychiatric disorders, namely schizophrenia, bipolar disorder, major depressive disorder, anxiety disorders, dementia and attention deficit hyperactivity disorder. Structural magnetic resonance imaging studies have reported smaller total cerebellar and vermal volumes in schizophrenia, mood disorders and attention deficit hyperactivity disorder. Functional magnetic resonance imaging studies using cognitive paradigms have shown alterations in cerebellar activity in schizophrenia, anxiety disorders and attention deficit hyperactivity disorder. In dementia, the cerebellum is affected in later stages of the disease. CONCLUSION: Contrasting with early theories...

Multicentric glioblastoma arising in two unusual sites: cerebellum and thalamus

Cambruzzi,Eduardo; Pêgas,Karla Lais; Simão,Mariana Fernandez; Stüker,Guilherme
Fonte: Sociedade Brasileira de Patologia Clínica; Sociedade Brasileira de Patologia; Sociedade Brasileira de Citopatologia Publicador: Sociedade Brasileira de Patologia Clínica; Sociedade Brasileira de Patologia; Sociedade Brasileira de Citopatologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2013 EN
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Multicentric glioblastomas (MGBM) arising in infra/supratentorial regions are uncommon lesions. The authors report a case of MGBM in a 61 year-old female patient, who presented a sudden onset of left hemiplegia. The magnetic resonance imaging (MRI) showed two expansive large lesions affecting cerebellum and thalamus, with strong contrast enhancement. The patient underwent resection of the cerebellar lesion. Microscopy revealed a high grade glial neoplasm exhibiting high mitotic index, areas of necrosis and microvascular proliferation. The neoplastic cells showed positive immunoexpression for glial fibrillary acidic protein (GFAP). The morphological findings were consistent with glioblastoma (GBM). The patient was referred to radiotherapy, with discrete signs of tumor regression after a 60-day clinical follow-up.

The role of the cerebellum in schizophrenia: from cognition to molecular pathways

Yeganeh-Doost,Peyman; Gruber,Oliver; Falkai,Peter; Schmitt,Andrea
Fonte: Faculdade de Medicina / USP Publicador: Faculdade de Medicina / USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
Relevância na Pesquisa
36.9%
Beside its role in motor coordination, the cerebellum is involved in cognitive function such as attention, working memory, verbal learning, and sensory discrimination. In schizophrenia, a disturbed prefronto-thalamo-cerebellar circuit has been proposed to play a role in the pathophysiology. In addition, a deficit in the glutamatergic N-methyl-D-aspartate (NMDAf) receptor has been hypothesized. The risk gene neuregulin 1 may play a major role in this process. We demonstrated a higher expression of the NMDA receptor subunit 2D in the right cerebellar regions of schizophrenia patients, which may be a secondary upregulation due to a dysfunctional receptor. In contrast, the neuregulin 1 risk variant containing at least one C-allele was associated with decreased expression of NMDA receptor subunit 2C, leading to a dysfunction of the NMDA receptor, which in turn may lead to a dysfunction of the gamma amino butyric acid (GABA) system. Accordingly, from post-mortem studies, there is accumulating evidence that GABAergic signaling is decreased in the cerebellum of schizophrenia patients. As patients in these studies are treated with antipsychotics long term, we evaluated the effect of long-term haloperidol and clozapine treatment in an animal model. We showed that clozapine may be superior to haloperidol in restoring a deficit in NMDA receptor subunit 2C expression in the cerebellum. We discuss the molecular findings in the light of the role of the cerebellum in attention and cognitive deficits in schizophrenia.

The role of the cerebellum in auditory processing using the SSI test

Sens,Patricia Maria; Almeida,Clemente Isnard Ribeiro de; Souza,Marisa Mara Neves de; Gonçalves,Josyane Borges A.; Carmo,Luiz Claudio do
Fonte: Associação Brasileira de Otorrinolaringologia e Cirurgia Cervicofacial Publicador: Associação Brasileira de Otorrinolaringologia e Cirurgia Cervicofacial
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2011 EN
Relevância na Pesquisa
36.9%
The Synthetic Sentence Identification (SSI) test assesses central auditory pathways by measuring auditory and visual sensitivity and testing selective attention. Cerebellum activation in auditory attention and sensorial activity modulation have already been described. Assessing patients with cerebellar lesions alone using the SSI test can confirm the role of the cerebellum in auditory processing. AIM: To evaluate the role of the cerebellum in auditory processing in individuals with normal hearing and in those with chronic cerebellum lesions, using the SSI test. MATERIALS AND METHODS: Cross-sectional cohort study. A study group comprising 18 patients with chronic cerebellar lesion and a control group of 20 healthy individuals were assessed. The SSI test was applied in an Ipsilateral Competitive Message (ICM) and Contralateral Competitive Message (CCM) modes. To compare the results between groups, we used the chi-square test for qualitative variables. RESULTS: A statistically significant difference was found between the study and control groups using the ICM mode of the SSI test (p=0.035), but not in the CCM mode (p=0.083). CONCLUSION: The results on the SSI confirmed cerebellar participation in auditory processing in individuals with chronic cerebellar lesions and in those with normal hearing assessed in this study.

Consensus Paper: The Role of the Cerebellum in Perceptual Processes

Baumann, Oliver; Borra, Ronald J.; Bower, James M.; Cullen, Kathleen E.; Habas, Christophe; Ivry, Richard B.; Leggio, Maria; Mattingley, Jason B.; Molinari, Marco; Moulton, Eric A.; Paulin, Michael G.; Pavlova, Marina A.; Schmahmann, Jeremy D.; Sokolov, A
Fonte: Springer US Publicador: Springer US
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
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Various lines of evidence accumulated over the past 30 years indicate that the cerebellum, long recognized as essential for motor control, also has considerable influence on perceptual processes. In this paper, we bring together experts from psychology and neuroscience, with the aim of providing a succinct but comprehensive overview of key findings related to the involvement of the cerebellum in sensory perception. The contributions cover such topics as anatomical and functional connectivity, evolutionary and comparative perspectives, visual and auditory processing, biological motion perception, nociception, self-motion, timing, predictive processing, and perceptual sequencing. While no single explanation has yet emerged concerning the role of the cerebellum in perceptual processes, this consensus paper summarizes the impressive empirical evidence on this problem and highlights diversities as well as commonalities between existing hypotheses. In addition to work with healthy individuals and patients with cerebellar disorders, it is also apparent that several neurological conditions in which perceptual disturbances occur, including autism and schizophrenia, are associated with cerebellar pathology. A better understanding of the involvement of the cerebellum in perceptual processes will thus likely be important for identifying and treating perceptual deficits that may at present go unnoticed and untreated. This paper provides a useful framework for further debate and empirical investigations into the influence of the cerebellum on sensory perception.

Studies with the Golgi method in central gangliogliomas and dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos disease)

Ferrer, I.; Martí, E.; Guionneti, N.; Bella, R.; Serrano, T.; Towse, J.; Conesa, G.; Isamat, F.
Fonte: Murcia : F. Hernández Publicador: Murcia : F. Hernández
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
36.63%
The rapid Golgi method, combined with current optical and electronmicroscopica1 techniques, was used in three central gangliogliomas and in one dysplastic gangliocytoma of the cerebellum to study the morphology of ganglionic cells. Gangliogliomas were composed of bipolar, fusiform and radiate cells with dense core and clear vesicles in the perikaryon and cellular processes, the number of each cellular type varying from one case to another. These features, together with the fact that isodendritic neurons are considered to be phylogenetically old neurons, suggest that these tumours are composed of «primitive» neurons that are not homogeneous with regard to their morphology. In contrast, ganglionic cells in dysplastic gangliocytoma are huge cells with long, stereotyped neurites that establish unique asymmetric contacts with neighbouring perikarya and neurites by means of claw-shaped processes covered with synaptic buttons. These morphological characteristics are different from those of any other neuron of the CNS.

65Zn uptake in the rat cerebellum and brainstem

Vera-Gil, A.; Perez-Castejon, M.C.; Lahoz, M.; Aisa, J.; Recreo, M.P.; Serrano, P.; Pes, N.
Fonte: Murcia : F. Hernández Publicador: Murcia : F. Hernández
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
36.84%
We have studied the autoradiographic uptake of 65Zn in the cerebellum and brainstem of the rat, contrasting these results with Timm’s positivity in these structures. Both, autoradiographic uptake and histochemical positivity, have demonstrated Zinc in a location that could be accepted as in climbing fibres and glomeruli of the cerebellum cortex, and also in brainstem neurons that project their axons to the cerebellum cortex, suggesting a circuit where zinc may act as a neuromodulator.

Golgi apparatus localization of ZNT7 in the mouse cerebellum

Gao, Hui-Ling; Feng, Wan-Yu; Li, Xiao-Ling; Xu, He; Huang, Liping; Wang, Zhan-You
Fonte: Murcia : F. Hernández Publicador: Murcia : F. Hernández
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
36.84%
We have recently reported that four members of the zinc transporter (ZNT) family, ZNT1, ZNT3, ZNT4, and ZNT6, are abundantly expressed in the mouse cerebellum. In the present study, we reported that ZNT7 was present throughout the cerebellar cortex. ZNT7 immunoreactivity was predominately present in the somas and primary dendrites of the Purkinje cells. ZNT7 was also present in the Bergmann glial cell bodies as well as their radial processes, which extended into the molecular cell layer. Confocal immunofluorescence results demonstrated that the expression of ZNT7 overlapped with that of TGN38 in the somas of the Purkinje cells and granule cells. Immuno-electron microscopic study showed that ZNT7 was localized to the membrane of the Golgi apparatus in the somas of the Purkinje cells, Bergmann glial cells, and granule cells. Western blot analysis demonstrated that a considerable amount of ZNT7 was expressed in the cerebellum. These findings suggest a significant role of ZNT7 in zinc homeostasis in the mouse cerebellum.

Ultrastructural alterations of the rabbit sciatic nerve, spinal cord and cerebellum, following methionine sulphoximine administration

Kallaras, C.; Anogianakis, G.; Apostolakis, M.; Manthos, A.; Sioga, A.; Economou, L.; Foroglou, Ch.
Fonte: Murcia : F. Hernández Publicador: Murcia : F. Hernández
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
36.63%
Methii~nine suluhoximine (MSO) is a centrally ácting neurutoxin wh'ich inhibits the glutainate nietabolism enzymes and has convulsive properties. Sniall doses of MSO were administered to rabbits. either intra\,eiiously (IV) or intracerebroventricularly (ICV), anil electron microscopic examination of the cerebellum. the spinal cord and the sciatic nerve was perforined on the first day of rabbit hind leg rigid paralysis (myopathy with histvlogical findings resenibling myositis). which set in by [he 2nd to 4th day after MSO administration. In thc cerebelluin focal minor alterations were hund in the astrocytes (swelling and lucidity. diminution of glycogen graiiules) and sparsely in the presynaptic terminals (luciditj. and clumping). whereas inost of the neuron prescnted a nornial appearance. In the spinal cord and in the sciatic nerve a dissociation of the axon from the iiiyelin shcath was evident in a small number of niyelinatcd nerve fibres, along with the appearance of vacuolated spaces. Mitochondrial disorganisation in the axons. as well as glial cell alterations, were also seen. Th c u l t r a s t r u c t ~ ~ r aall terat ions we r e non spe c i f i c , Lind siiice they wcre induced 2 to 4 days after the adniiriistration of either minimum doses (IV) or of exti-cmely low doses (ICV) of MSO...

The role of the cerebellum in schizophrenia: from cognition to molecular pathways

Yeganeh-Doost, Peyman; Gruber, Oliver; Falkai, Peter; Schmitt, Andrea
Fonte: Universidade de São Paulo. Faculdade de Medicina Publicador: Universidade de São Paulo. Faculdade de Medicina
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/01/2011 ENG
Relevância na Pesquisa
36.9%
Beside its role in motor coordination, the cerebellum is involved in cognitive function such as attention, working memory, verbal learning, and sensory discrimination. In schizophrenia, a disturbed prefronto-thalamo-cerebellar circuit has been proposed to play a role in the pathophysiology. In addition, a deficit in the glutamatergic N-methyl-D-aspartate (NMDAf) receptor has been hypothesized. The risk gene neuregulin 1 may play a major role in this process. We demonstrated a higher expression of the NMDA receptor subunit 2D in the right cerebellar regions of schizophrenia patients, which may be a secondary upregulation due to a dysfunctional receptor. In contrast, the neuregulin 1 risk variant containing at least one C-allele was associated with decreased expression of NMDA receptor subunit 2C, leading to a dysfunction of the NMDA receptor, which in turn may lead to a dysfunction of the gamma amino butyric acid (GABA) system. Accordingly, from post-mortem studies, there is accumulating evidence that GABAergic signaling is decreased in the cerebellum of schizophrenia patients. As patients in these studies are treated with antipsychotics long term, we evaluated the effect of long-term haloperidol and clozapine treatment in an animal model. We showed that clozapine may be superior to haloperidol in restoring a deficit in NMDA receptor subunit 2C expression in the cerebellum. We discuss the molecular findings in the light of the role of the cerebellum in attention and cognitive deficits in schizophrenia.

SOX3 expression in the glial system of the developing and adult mouse cerebellum

Cheah, P.S.; Thomas, P.Q.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em //2015 EN
Relevância na Pesquisa
36.99%
BACKGROUND: The cerebellum plays a vital role in equilibrium, motor control, and motor learning. The discrete neural and glial fates of cerebellar cells are determined by the molecular specifications (e.g. transcription factors) of neuroprogenitor cells that are influenced by local microenvironment signals. In this study, we evaluated the expression and function of Sox3, a single-exon gene located on the X chromosome, in the developing cerebellum. RESULT: In the embryonic and early postnatal cerebellum, SOX3-positive-cells were detected in the ventricular zone, indicating that SOX3 expression is present in a subset of the cerebellar precursor cell population. In the young adult cerebellum, this expression was diminished in cerebellar cells, suggesting its limited role in cerebellar progenitors. SOX3-positive-cells were also found in the cerebellar mantle zone. Further immunohistochemistry analyses revealed that SOX3 was not expressed in Purkinje neurons. Using glial markers in the early postnatal cerebellum, we found that virtually all of the SOX3-positive-cells were glial cells, although not all glial cells were SOX3-positive-cells. We also determined the impact of transgenic expression using a loss-of-function (Sox3 null) model. We did not observe any developmental defects in the cerebellum of the Sox3 null mice. CONCLUSIONS: Our results indicate that the SOX3 protein is not expressed in cerebellar neurons and is instead expressed exclusively in the cerebellar glial system in a subset of mature glial cells. Although the expression of Sox3 cerebellar glial development is lineage-restricted...

Automatic Segmentation of the Cerebellum in Ultrasound Volumes of the Fetal Brain

Velásquez Rodríguez,G.; Arámbula Cosío,F.; Guzmán Huerta,M.E.; Camargo Marín,L.; Borboa Olivares,H.; Escalante Ramírez,Boris
Fonte: Sociedad Mexicana de Ingeniería Biomédica Publicador: Sociedad Mexicana de Ingeniería Biomédica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2015 EN
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The size of the cerebellum in ultrasound volumes of the fetal brain has shown a high correlation with gestational age, which makes it a valuable feature to detect fetal growth restrictions. Manual annotation of the 3D surface of the cerebellum in an ultrasound volume is a time consuming task, which needs to be performed by a highly trained expert. In order to assist the experts in the evaluation of cerebellar dimensions, we developed an automatic scheme for the segmentation of the 3D surface of the cerebellum in ultrasound volumes, using a spherical harmonics model. In this work we present our validation results on 10 ultrasound volumes in which we have obtained an adequate accuracy in the segmentation of the cerebellum (mean Dice coefficient of 0.689). The method reported shows potential to effectively assist the experts in the assessment of fetal growth in ultrasound volumes.