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1.
Sleep ; 46(4)2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36718043

RESUMO

The mechanisms by which the genotype interacts with nutrition during development to contribute to the variation of complex behaviors and brain morphology of adults are not well understood. Here we use the Drosophila Genetic Reference Panel to identify genes and pathways underlying these interactions in sleep behavior and mushroom body morphology. We show that early-life nutritional restriction effects on sleep behavior and brain morphology depends on the genotype. We mapped genes associated with sleep sensitivity to early-life nutrition, which were enriched for protein-protein interactions responsible for translation, endocytosis regulation, ubiquitination, lipid metabolism, and neural development. By manipulating the expression of candidate genes in the mushroom bodies (MBs) and all neurons, we confirm that genes regulating neural development, translation and insulin signaling contribute to the variable response of sleep and brain morphology to early-life nutrition. We show that the interaction between differential expression of candidate genes with nutritional restriction in early life resides in the MBs or other neurons and that these effects are sex-specific. Natural variations in genes that control the systemic response to nutrition and brain development and function interact with early-life nutrition in different types of neurons to contribute to the variation of brain morphology and adult sleep behavior.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Masculino , Feminino , Drosophila melanogaster/genética , Drosophila/genética , Encéfalo/fisiologia , Sono/fisiologia , Genes Controladores do Desenvolvimento
2.
Front Cell Dev Biol ; 10: 874362, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35982851

RESUMO

Cell segregation mechanisms play essential roles during the development of the central nervous system (CNS) to support its organization into distinct compartments. The Slit protein is a secreted signal, classically considered a paracrine repellent for axonal growth through Robo receptors. However, its function in the compartmentalization of CNS is less explored. In this work, we show that Slit and Robo3 are expressed in the same neuronal population of the Drosophila optic lobe, where they are required for the correct compartmentalization of optic lobe neuropils by the action of an autocrine/paracrine mechanism. We characterize the endocytic route followed by the Slit/Robo3 complex and detected genetic interactions with genes involved in endocytosis and actin dynamics. Thus, we report that the Slit-Robo3 pathway regulates the morphogenesis of the optic lobe through an atypical autocrine/paracrine mechanism in addition to its role in axon guidance, and in association with proteins of the endocytic pathway and small GTPases.

3.
Front Cell Dev Biol ; 9: 612645, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968921

RESUMO

Neurogenesis is achieved through a sequence of steps that include specification and differentiation of progenitors into mature neurons. Frequently, precursors migrate to distinct positions before terminal differentiation. The Slit-Robo pathway, formed by the secreted ligand Slit and its membrane bound receptor Robo, was first discovered as a regulator of axonal growth. However, today, it is accepted that this pathway can regulate different cellular processes even outside the nervous system. Since most of the studies performed in the nervous system have been focused on axonal and dendritic growth, it is less clear how versatile is this signaling pathway in the developing nervous system. Here we describe the participation of the Slit-Robo pathway in the development of motion sensitive neurons of the Drosophila visual system. We show that Slit and Robo receptors are expressed in different stages during the neurogenesis of motion sensitive neurons. Furthermore, we find that Slit and Robo regulate multiple aspects of their development including neuronal precursor migration, cell segregation between neural stem cells and daughter cells and formation of their connectivity pattern. Specifically, loss of function of slit or robo receptors in differentiated motion sensitive neurons impairs dendritic targeting, while knocking down robo receptors in migratory progenitors or neural stem cells leads to structural defects in the adult optic lobe neuropil, caused by migration and cell segregation defects during larval development. Thus, our work reveals the co-option of the Slit-Robo signaling pathway in distinct developmental stages of a neural lineage.

4.
Int J Dev Biol ; 65(4-5-6): 251-261, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32930355

RESUMO

The development of multicellular organisms involves three main events: differentiation, growth, and morphogenesis. These processes need to be coordinated for a correct developmental program to work. Mechanisms of cell segregation and the formation of boundaries during development play essential roles in this coordination, allowing the generation and maintenance of distinct regions in an organism. These mechanisms are also at work in the nervous system. The process of regionalization involves first the patterning of the developing organism through gradients and the expression of transcription factors in specific regions. Once different tissues have been induced, segregation mechanisms may operate to avoid cell mixing between different compartments. Three mechanisms have been proposed to achieve segregation: (1) differential affinity, which mainly involves the expression of distinct pools of adhesion molecules such as members of the cadherin superfamily; (2) contact inhibition, which is largely mediated by Eph-ephrin signaling; and (3) cortical tension, which involves the actomyosin cytoskeleton. In many instances, these mechanisms collaborate in cell segregation. In the last three decades, there have been several advances in our understanding of how cell segregation and boundaries participate in the development of the nervous system. Interestingly, as in other aspects of development, the molecular players are remarkably similar between vertebrates and invertebrates. Here we summarize the main concepts of cell segregation and boundary formation, focusing on the nervous system and highlighting the similarities between vertebrate and invertebrate model organisms.


Assuntos
Efrinas , Sistema Nervoso/embriologia , Organogênese , Actomiosina , Animais , Invertebrados/embriologia , Vertebrados/embriologia
5.
Neurologia (Engl Ed) ; 35(7): 451-457, 2020 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29249302

RESUMO

INTRODUCTION: The paramedian lobule of the cerebellum is involved in learning to correctly perform motor skills through practice. Dendritic spines are dynamic structures that regulate excitatory synaptic stimulation. We studied plastic changes occurring in the dendritic spines of Purkinje cells from the paramedian lobule of rats during motor learning. METHODS: Adult male rats were trained over a 6-day period using an acrobatic motor learning paradigm; the density and type of dendritic spines were determined every day during the study period using a modified version of the Golgi method. RESULTS: The learning curve reflected a considerable decrease in the number of errors made by rats as the training period progressed. We observed more dendritic spines on days 2 and 6, particularly more thin spines on days 1, 3, and 6, fewer mushroom spines on day 3, fewer stubby spines on day 1, and more thick spines on days 4 and 6. CONCLUSION: The initial stage of motor learning may be associated with fast processing of the underlying synaptic information combined with an apparent "silencing" of memory consolidation processes, based on the regulation of the neuronal excitability.


Assuntos
Cerebelo/metabolismo , Espinhas Dendríticas/fisiologia , Aprendizagem/fisiologia , Células de Purkinje/fisiologia , Animais , Masculino , Destreza Motora/fisiologia , Plasticidade Neuronal/fisiologia , Plásticos , Ratos , Ratos Sprague-Dawley
6.
Dev Biol ; 458(1): 32-42, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606342

RESUMO

The complexity of the nervous system requires the coordination of multiple cellular processes during development. Among them, we find boundary formation, axon guidance, cell migration and cell segregation. Understanding how different cell populations such as glial cells, developing neurons and neural stem cells contribute to the formation of boundaries and morphogenesis in the nervous system is a critical question in neurobiology. Slit is an evolutionary conserved protein essential for the development of the nervous system. For signaling, Slit has to bind to its cognate receptor Robo, a single-pass transmembrane protein. Although the Slit/Robo signaling pathway is well known for its involvement in axon guidance, it has also been associated to boundary formation in the Drosophila visual system. In the optic lobe, Slit is expressed in glial cells, positioned at the boundaries between developing neuropils, and in neurons of the medulla ganglia. Although it has been assumed that glial cells provide Slit to the system, the contribution of the neuronal expression has not been tested. Here, we show that, contrary to what was previously thought, Slit protein provided by medulla neurons is also required for boundary formation and morphogenesis of the optic lobe. Furthermore, tissue specific rescue using modified versions of Slit demonstrates that this protein acts at long range and does not require processing by extracellular proteases. Our data shed new light on our understanding of the cellular mechanisms involved in Slit function in the fly visual system morphogenesis.


Assuntos
Orientação de Axônios/fisiologia , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Neurônios/fisiologia , Neurópilo/fisiologia , Lobo Óptico de Animais não Mamíferos/crescimento & desenvolvimento , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Elementos Facilitadores Genéticos , Técnicas de Silenciamento de Genes , Genes Reporter , Estudos de Associação Genética , Larva , Morfogênese , Mutação , Proteínas do Tecido Nervoso/genética , Neuroglia/fisiologia , Neurópilo/citologia , Lobo Óptico de Animais não Mamíferos/citologia , Especificidade de Órgãos , Fenótipo , Estimulação Luminosa , Pupa , Interferência de RNA , Receptores Imunológicos/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Transgenes , Proteínas Roundabout
7.
Rev. Esp. Cir. Ortop. Traumatol. (Ed. Impr.) ; 62(1): 71-79, ene.-feb. 2018. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-170350

RESUMO

Introducción. Las fracturas diafisarias del antebrazo constituyen el 6-10% de todas las fracturas en niños. El tratamiento depende de la edad y el tipo de desplazamiento y son válidos el manejo conservador y quirúrgico con fijación de clavos intramedulares entre otros. El objetivo es mostrar los resultados radiológicos y funcionales, y las complicaciones de la fijación intramedular con clavos de Kirschner en niños. Materiales y métodos. Es una serie de casos retrospectiva descriptiva de pacientes operados con fijación intramedular de fracturas de antebrazo. Se correlacionan los resultados radiológicos y funcionales y las complicaciones. Resultados. De 117 pacientes operados, 59 cumplían criterios de inclusión. La edad promedio fue 10 años. El 84,7% de ellos fueron hombres y el izquierdo el lado más afectado (62,7%). El 88,1% de ambos huesos estaban fracturados y 11 casos tenían fracturas abiertas. Se realizó reducción abierta en el 72,8% de los casos cuyas principales indicaciones fueron inestabilidad, reducción fallida y refractura. Se tuvieron 52 resultados excelentes, 2 buenos, 4 regulares y uno malo. Hubo un 13,5% de complicaciones menores. Discusión. Este estudio muestra que la fijación intramedular con clavos de Kirschner en fracturas de diáfisis de radio y cúbito de niños es un procedimiento seguro, de bajo costo y que ofrece a corto y mediano plazo adecuados resultados funcionales, con una prevalencia baja de complicaciones graves, con solo 6 casos de no consolidación y refracturas. Las angulaciones preoperatorias mayores en los planos anteroposterior y lateral, y angulaciones posoperatorias en el plano lateral, podrían considerarse predictores de resultados funcionales menos satisfactorios (AU)


Introduction. Diaphyseal fractures of the forearm comprise 6%-10% of all fractures in children. The treatment depends on the age and type of displacement, and conservative and surgical management with fixation of intramedullary nails, among other techniques, is valid. The aim is to show the radiological and functional outcomes, and complications of intramedullary fixation with Kirschner nails in children. Materials and methods. A retrospective descriptive case series of patients treated with intramedullary fixation of forearm fractures. The radiological and functional results, and complications are correlated. Results. Of the 117 patients operated, 59 met the inclusion criteria. The average age was 10 years. Eighty-four point seven percent were males and the left side was the most affected (62.7%). In 88.1% both bones were fractured and 11 cases had open fractures. An open reduction was performed in 72.8% of the cases, the main indications for this being instability, failed reduction and refracture. There were 52 excellent outcomes, 2 good, and 4 regular and 1 bad. There were 13.5% minor complications. Discussion. This study shows that intramedullary fixation with Kirschner nails in radius and ulna diaphysis fractures in children is a safe, low-cost procedure and offers adequate short and medium term functional outcomes, with a low prevalence of serious complications with only 6 cases of non-consolidation and refracture. Larger preoperative angulations in the anteroposterior and lateral planes, and lateral postoperative angulations, could be considered predictors of less satisfactory functional results (AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Traumatismos do Antebraço/cirurgia , Diáfises/cirurgia , Fixação Intramedular de Fraturas/métodos , Fraturas da Ulna/cirurgia , Fraturas do Rádio/cirurgia , Pinos Ortopédicos , Estudos Retrospectivos , Resultado do Tratamento
8.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29107555

RESUMO

INTRODUCTION: Diaphyseal fractures of the forearm comprise 6%-10% of all fractures in children. The treatment depends on the age and type of displacement, and conservative and surgical management with fixation of intramedullary nails, among other techniques, is valid. The aim is to show the radiological and functional outcomes, and complications of intramedullary fixation with Kirschner nails in children. MATERIALS AND METHODS: A retrospective descriptive case series of patients treated with intramedullary fixation of forearm fractures. The radiological and functional results, and complications are correlated. RESULTS: Of the 117 patients operated, 59 met the inclusion criteria. The average age was 10 years. Eighty-four point seven percent were males and the left side was the most affected (62.7%). In 88.1% both bones were fractured and 11 cases had open fractures. An open reduction was performed in 72.8% of the cases, the main indications for this being instability, failed reduction and refracture. There were 52 excellent outcomes, 2 good, and 4 regular and 1 bad. There were 13.5% minor complications. DISCUSSION: This study shows that intramedullary fixation with Kirschner nails in radius and ulna diaphysis fractures in children is a safe, low-cost procedure and offers adequate short and medium term functional outcomes, with a low prevalence of serious complications with only 6 cases of non-consolidation and refracture. Larger preoperative angulations in the anteroposterior and lateral planes, and lateral postoperative angulations, could be considered predictors of less satisfactory functional results.


Assuntos
Fios Ortopédicos , Fixação Intramedular de Fraturas/métodos , Fraturas do Rádio/cirurgia , Fraturas da Ulna/cirurgia , Adolescente , Criança , Pré-Escolar , Diáfises/diagnóstico por imagem , Diáfises/lesões , Diáfises/cirurgia , Feminino , Seguimentos , Fixação Intramedular de Fraturas/instrumentação , Humanos , Masculino , Radiografia , Fraturas do Rádio/diagnóstico por imagem , Estudos Retrospectivos , Resultado do Tratamento , Fraturas da Ulna/diagnóstico por imagem
9.
Sci Rep ; 7(1): 16622, 2017 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-29192163

RESUMO

Quantum entanglement lies at the heart of quantum information and quantum metrology. In quantum metrology, with a colossal amount of quantum Fisher information (QFI), entangled systems can be ameliorated to be a better resource scheme. However, noisy channels affect the QFI substantially. This research work seeks to investigate how QFI of N-qubit Greenberger-Horne-Zeilinger (GHZ) state is affected when subjected to decoherence channels: bit-phase flip (BPF) and generalize amplitude damping (GAD) channels, which can be induced experimentally. We determine the evolution under these channels, deduce the eigenvalues, and then derive the QFI. We found that when there is no interaction with the environment, the Heisenberg limit can be achieved via rotations along the z direction. It has been shown that in BPF channel, the maximal mean QFI of the N-qubit GHZ state ([Formula: see text]) dwindles as decoherence rate (p B ) increases due to flow of information from the system to the environment, until p B = 0.5, then revives to form a symmetric around p B = 0.5. Thus, p B > 0.5 leads to a situation where more noise yields more efficiency. We found that in GAD channel, at finite temperature, QFIs decay more rapidly than at zero temperature. Our results also reveal that QFI can be enhanced by adjusting the temperature of the environment.

10.
Rev. clín. med. fam ; 8(1): 66-70, feb. 2015. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-136760

RESUMO

Presentamos el caso de una adolescente de 16 años de edad que, estando previamente asintomática y sin historia clínica de haber padecido ninguna migraña, presenta de manera progresiva, en el plazo de una semana, una cefalea holocraneal de características pulsátiles, que no mejoraba con analgésicos a dosis altas. Ante la persistencia del cuadro y los criterios de alarma que presentaba fue fundamental el uso de la Resonancia Magnética Nuclear (RMN) para su diagnóstico (AU)


We report the case of a 16-year-old female teenager, previously asymptomatic and without a medical record of migraine-like headaches, who progressively developed a pulsating holocraneal headache, which did not improve with high doses of painkillers. Given the persistence of the clinical picture and the alarm criteria, the use of Nuclear Magnetic Resonance (RMN) was fundamental for achieving an accurate diagnosis (AU)


Assuntos
Adolescente , Feminino , Humanos , Cefaleia/complicações , Cefaleia/etiologia , Cefaleia , Transtornos da Cefaleia/etiologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Trombose Venosa/complicações , Etinilestradiol/efeitos adversos , Atenção Primária à Saúde/métodos , Atenção Primária à Saúde/tendências , Fatores de Risco , Fotofobia/complicações , Anticoncepcionais Orais/efeitos adversos , Diagnóstico Diferencial
11.
Rev. clín. med. fam ; 7(3): 223-226, oct. 2014. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-133054

RESUMO

Presentamos el caso de una mujer de 74 años de edad que estando previamente bien presenta de manera súbita dolor interescapular acompañado de alteración de la sensibilidad y la fuerza en miembro superior izquierdo. Ante esta clínica se solicitó Resonancia Magnética Nuclear (RMN) que confirmó el diagnóstico de hematoma cervical epidural espontáneo (AU)


The present is the case of a 74 years old previously healthy woman who felt sudden interscapular pain along with strength and sensitivity impairment in her right arm. Facing these clinical symptoms, a Magnetic Resonance Imaging test (MRI) was performed which confirmed the diagnosis of spontaneous cervical epidural hematoma (AU)


Assuntos
Humanos , Feminino , Idoso , Hematoma Epidural Espinal/complicações , Hematoma Epidural Espinal/cirurgia , Hematoma Epidural Espinal , Compressão da Medula Espinal/complicações , Compressão da Medula Espinal , Paresia/complicações , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética
12.
Seizure ; 18(7): 533-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19447049

RESUMO

It has been described that febrile seizures during infancy increase risk of subsequent non-febrile seizures during the adulthood. However, latency period between febrile seizure and the onset of the first spontaneous seizure has not been evaluated. The present study was designed to investigate the susceptibility to subsequent seizures in immature rats that had experienced early-life hyperthermic seizures and before they achieved the adult age. The results were compared with those induced by hyperthermia alone. Pentylenetetrazol (PTZ) was applied 24h or 20 days after hyperthermic seizures or hyperthermia were induced in 10-day-old rats by a regulated stream of moderately heated air. One day after hyperthermic seizures or hyperthermia, animals demonstrated enhanced latency to the PTZ-induced myoclonic (88% and 53%, respectively), clonic (60% and 60%, respectively) and tonic seizures (233% and 659%, respectively). The incidence of myoclonic and clonic seizures was similar to that in control group (100%). However, hyperthermic seizures reduced (50%) the incidence of tonic seizures. Twenty days after hyperthermic seizures there was an augmented latency to tonic seizures (123%) and reduced incidence for all the PTZ-induced seizures (71% myoclonic; 71% clonic seizures; 57% tonic seizures) when compared with control group (100%). In contrast, hyperthermia enhanced only the latency to myoclonic (133%) and clonic seizures (659%). Our data indicate that hyperthermic seizures or hyperthermia induces a protective effect against PTZ-induced seizures during a latency period. A possible involvement of gamma-aminobutyric acid (GABA) system is discussed.


Assuntos
Febre/fisiopatologia , Convulsões/induzido quimicamente , Animais , Animais Recém-Nascidos , Convulsivantes/farmacologia , Modelos Animais de Doenças , Feminino , Masculino , Pentilenotetrazol/farmacologia , Gravidez , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Convulsões/classificação , Fatores de Tempo
13.
Cell Mol Neurobiol ; 27(2): 211-27, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16802192

RESUMO

Effects of hyperthermia-induced seizures (HS) on GABA(A) and benzodiazepine (BDZ) receptor binding in immature rat brain were evaluated using in vitro autoradiography. HS were induced in 10-days-old rats by a regulated stream of moderately heated air directed 50 cm above the animals. Rats were killed 30 min, 24 h or 20 days after HS and their brains were used for in vitro autoradiography experiments to determine GABA(A) and BDZ receptor binding. GABA(A) binding was significantly enhanced in all brain areas evaluated 30 min after HS, an effect that endures 24 h and 20 days after seizures. Concerning BDZ receptor binding, a significant increase was detected in entorhinal and perirhinal cortices and decreased in basolateral amygdala 30 min following HS. One day after HS, animals demonstrated enhanced BDZ binding in the cingulate, frontal, posterior parietal, entorhinal, temporal and perirhinal cortices; striatum, accumbens, substantia nigra pars compacta and amygdala nuclei. Twenty days after HS enhanced BDZ binding was restricted in the cingulated, frontal, anterior and posterior parietal cortices, as well as in substantia nigra pars reticulata, whereas decreased values were found in accumbens nucleus and substantia nigra pars compacta. Our data indicate differential effects of HS in GABA(A) and BDZ binding in immature brain. HS-induced GABA(A) and BDZ changes are different from those previously described in experimental models of temporal lobe epilepsy in adult animals.


Assuntos
Encéfalo/metabolismo , Febre/complicações , Receptores de GABA-A/metabolismo , Convulsões Febris/etiologia , Convulsões Febris/metabolismo , Fatores Etários , Animais , Autorradiografia , Encéfalo/diagnóstico por imagem , Feminino , Flunitrazepam/metabolismo , Flunitrazepam/farmacologia , Agonistas GABAérgicos/metabolismo , Agonistas GABAérgicos/farmacologia , Moduladores GABAérgicos/metabolismo , Moduladores GABAérgicos/farmacologia , Masculino , Muscimol/metabolismo , Muscimol/farmacologia , Gravidez , Cintilografia , Ratos , Ratos Sprague-Dawley , Convulsões Febris/diagnóstico por imagem , Trítio
14.
Ansiedad estrés ; 12(1): 45-61, jun. 2006. ilus
Artigo em Es | IBECS | ID: ibc-046600

RESUMO

Con el objetivo de integrar el estudio de los síntomas psicosomáticos a la teoría transaccional del estrés. Se presenta un modelo explicativo de los síntomas psicosomáticos basados en la teoría transaccional del estrés de Lazarus, en el cual se incluyen análisis de estudios realizados con el propósito de valorar o explicar los síntomas psicosomáticos y, el planteamiento de Sandín respecto al estrés, además de considerar otras variables que han sido relacionadas a los síntomas psicosomáticos


The aim of this paper is to integrate the psychosomatic symptoms' study in to the transactional mediational theory. An explanatory model of the psychosomatic symptoms, based on the Lazarus' transactional mediational theory of stress is presented; Additionally the analysis of studies carried out for the purpose ofvaluing or to explain the psychosomatic symptoms, in the Sandin's approaches of stress are included. Finally we considering other variables that have been related to the psychosomatic symptoms


Assuntos
Humanos , Análise Transacional/métodos , Transtornos Psicofisiológicos/epidemiologia , Estresse Psicológico/fisiopatologia , Transtornos Somatoformes/epidemiologia , Estresse Psicológico/psicologia
15.
Cell Mol Neurobiol ; 25(6): 955-71, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16392029

RESUMO

Effects of hyperthermia-induced seizures (HS) on GABAA and benzodiazepine (BDZ) receptor binding in immature rat brain were evaluated using in vitro autoradiography. HS were induced in 10-day-old rats by a regulated stream of moderately heated air directed 50 cm above the animals. Rats were killed 30 min, 24 h, or 20 days after HS and their brains were used for in vitro autoradiography experiments to determine GABAA and BDZ receptor binding. GABAA binding was significantly enhanced in all brain areas evaluated 30 min after HS, an effect that endures 24 h and 20 days after seizures. Concerning BDZ receptor binding, a significant increase was detected in entorhinal and perirhinal cortices and decreased in basolateral amygdala 30 min following HS. One day after HS, animals demonstrated enhanced BDZ binding in the cingulate, frontal, posterior parietal, entorhinal, temporal, and perirhinal cortices; striatum, accumbens, substantia nigra pars compacta, and amygdala nuclei. Twenty days after HS enhanced BDZ binding was restricted in the cingulated, frontal, anterior and posterior parietal cortices, as well as in substantia nigra pars reticulata, whereas decreased values were found in accumbens nucleus and substantia nigra pars compacta. Our data indicate differential effects of HS in GABAA and BDZ binding in immature brain. HS-induced GABAA and BDZ changes are different from those previously described in experimental models of temporal lobe epilepsy in adult animals.


Assuntos
Febre , Receptores de GABA-A/metabolismo , Convulsões/metabolismo , Animais , Animais Recém-Nascidos , Autorradiografia , Encéfalo/anatomia & histologia , Criança , Feminino , Flunitrazepam/metabolismo , Agonistas GABAérgicos/metabolismo , Moduladores GABAérgicos/metabolismo , Humanos , Masculino , Muscimol/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley , Convulsões/etiologia , Fatores de Tempo , Trítio/metabolismo
16.
J Econ Entomol ; 93(4): 1105-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10985019

RESUMO

The susceptibility of larvae, prepupae, and pupae of the grass looper Mocis latipes (Guenée) to the entomopathogenic nematode Heterorhabditis bacteriophora (Poinar) NC strain was evaluated under laboratory conditions. Concentrations of 0, 5, 10, 20, 40, 60, and 120 nematodes per larva, applied in 1 ml of sterile-distilled water, were bioassayed, applying them to groups of 20 individuals of each instar, prepupa or pupa. Mortality was recorded daily for 5 d. All instars and the prepupal stage were the most susceptible to H. bacteriophora. Mortality ranged from 22.5 to 100%. Prepupae had 97.5-100% mortality starting at 10 nematodes per prepupa. Pupal mortality ranged from 27.5 to 41.3% as nematode concentration was increased. H. bacteriophora presented LC50 values that ranged between 5.26 and 37.66 nematodes per larva and LT50 values that ranged between 1.5 and 4.3 d. Results of this study suggest that H. bacteriophora has potential as a biocontrol agent against M. latipes.


Assuntos
Mariposas/parasitologia , Controle Biológico de Vetores/métodos , Rabditídios/patogenicidade , Animais
17.
Rev Invest Clin ; 52(5): 509-16, 2000.
Artigo em Espanhol | MEDLINE | ID: mdl-11195179

RESUMO

OBJECTIVE: To investigate if the changes in the activity of the tryptophan-5-hydroxylase and in brain serotonin synthesis provoked by diabetes mellitus persist or return to normal in the diabetic rats submitted to treatment with insulin. METHODS: Diabetes induced by the administration of streptozotocin in rats and their treatment with insulin was the paradigm used. At days 7, 14 and 21 of evolution, the brain serotonergic biosynthetic activity was evaluated. RESULTS: The diabetic rats showed a significant decrease of body weight. Also, they showed a low concentration of I-tryptophan, as well as a diminution in the activity of the key enzyme tryptophan-5-hydroxylase and its product serotonin in the cerebral cortex and brainstem. Interestingly, the activity of the enzyme was higher in the brainstem from day 14, accompanied with an elevation of the neurotransmitter. The diabetic rats submitted to treatment with insulin showed a complete physical recovery and a return to normal of plasma and brain I-tryptophan. The activity of the enzyme not only normalized but was elevated and with an increase of serotonin in the brainstem and cerebral cortex. CONCLUSION: The present findings confirm that diabetes mellitus produced a chronic anabolic deficit and a decrease in some brain regions of serotonin synthesis. Also, demonstrate that the diabetic rats under specific treatment with insulin had a complete physical recovery and a return to normal of the serotonin precursor in the blood and brain. However, the activity of the limiting enzyme TrpOH case was elevated with an increase of the neurotransmitter in all regions studied. Since the diabetic animal, insulin treated, does recover metabolically, the mechanism of activation of the serotonin biosynthetic path in the brain may not be dependent on the decreased availability of its precursor the free plasma I-tryptophan. Instead, it might be due to a change in the kinetics of tryptophan-5-hydroxylase, since its activity remains significantly increased in spite of plasma and brain normalization of its substrate. Altogether these changes in the biosynthesis of an important brain neurotransmitter may be of relevance in the pathophysiology of the psychoneurological complications in diabetic patients.


Assuntos
Encéfalo/metabolismo , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/metabolismo , Insulina/farmacologia , Serotonina/biossíntese , Animais , Masculino , Ratos , Ratos Wistar , Estreptozocina
18.
Rev Invest Clin ; 51(5): 293-302, 1999.
Artigo em Espanhol | MEDLINE | ID: mdl-10614139

RESUMO

OBJECTIVE: Evaluate if the rats with diabetes mellitus insulin-dependent have a minor activity of the serotonergic biosynthetic pathway through the decrease of the free fraction of L-tryptophan in plasma. METHODS: Diabetes mellitus was induced in rats, and the brain serotonergic biosynthetic activity was evaluated at 7, 14, and 21 days after streptozotocin administration. RESULTS: The diabetic animals showed a general decrease in body weight. In plasma they had a decrease in the free fraction of L-tryptophan. Also, in the brain they show low levels of the amino acid, as well as decrease of the activity of the limiting enzyme tryptophan-5-hydroxylase and its product serotonin. Interestingly, the activity of the enzyme was higher in the brainstem from day 14, accompanied with an elevation of the neurotransmitter. CONCLUSIONS: The results confirm that diabetes mellitus insulin-depend induce chronic undernourishment. The low levels of L-tryptophan in blood of the diabetic animals suggest a minor transport of the amino acid to the brain and a decrease in serotonin synthesis, in cerebral cortex and hypothalamus. Besides, during the evolution of the disease, the activity of tryptophan hydroxylase was elevated, independently of L-tryptophan concentration in the brainstem of diabetic animals, suggesting a different response according to the brain region and possibly a different functional change, accompanied by an increase in the synthesis of the neurotransmitter.


Assuntos
Encéfalo/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Serotonina/biossíntese , Animais , Masculino , Ratos , Ratos Wistar
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