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1.
Br J Oral Maxillofac Surg ; 59(2): e65-e71, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33358011

RESUMO

Head and neck cancer patients present unique airway challenges, and oropharyngeal, laryngeal, and hypopharyngeal tumours considerably distort and narrow the anatomy of the airway. We describe the use of 3D augmented reality software combined with 3D printed models to assess the anatomy of difficult airways and to assist in the formulation of the most optimal airway management strategy in such patients. The reported patients had computed tomograms (CT) of the neck prior to their anaesthetic and surgical management. DICOM files of the respective scans were imported to 3D rendering software (OsiriX, Pixmeo). We constructed volume rendered models for initial assessment of the airway then generated serial surface rendered models to create a virtual endoscopic path of the airway to simulate the fibreoptic approach. To further facilitate the study of difficult airways we have subsequently printed 3D models of those that were most difficult using rapid prototyping. Head and neck tumours significantly distort the airway. Thorough study of the relevant anatomy prior to airway management for operating reasons enhances communication between the surgeon and anaesthetist, and aids selection of the most appropriate intubation approach. In conclusion, this paper highlights a useful and novel pre-assessment strategy that allows a virtual, visual, 3-dimensional assessment of the airway anatomy combined with 3D modelling and 3D printing. This enables the airway specialist, anaesthetist, and head and neck surgeon to anticipate any critical steps and adjust the plan accordingly.


Assuntos
Modelos Anatômicos , Impressão Tridimensional , Endoscopia , Humanos , Imageamento Tridimensional , Pescoço , Software
2.
Phys Rev Lett ; 125(26): 262301, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33449792

RESUMO

Flow coefficients v_{n} of the orders n=1-6 are measured with the High-Acceptance DiElectron Spectrometer (HADES) at GSI for protons, deuterons, and tritons as a function of centrality, transverse momentum, and rapidity in Au+Au collisions at sqrt[s_{NN}]=2.4 GeV. Combining the information from the flow coefficients of all orders allows us to construct for the first time, at collision energies of a few GeV, a multidifferential picture of the angular emission pattern of these particles. It reflects the complicated interplay between the effect of the central fireball pressure on the emission of particles and their subsequent interaction with spectator matter. The high precision information on higher order flow coefficients is a major step forward in constraining the equation of state of dense baryonic matter.

3.
Phys Rev Lett ; 123(2): 022002, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386541

RESUMO

We present the first observation of K^{-} and ϕ absorption within nuclear matter by means of π^{-}-induced reactions on C and W targets at an incident beam momentum of 1.7 GeV/c studied with HADES at SIS18/GSI. The double ratio (K^{-}/K^{+})_{W}/(K^{-}/K^{+})_{C} is found to be 0.319±0.009(stat)_{-0.012}^{+0.014}(syst) indicating a larger absorption of K^{-} in heavier targets as compared to lighter ones. The measured ϕ/K^{-} ratios in π^{-}+C and π^{-}+W reactions within the HADES acceptance are found to be equal to 0.55±0.04(stat)_{-0.07}^{+0.06}(syst) and to 0.63±0.06(stat)_{-0.11}^{+0.11}(syst), respectively. The similar ratios measured in the two different reactions demonstrate for the first time experimentally that the dynamics of the ϕ meson in nuclear medium is strongly coupled to the K^{-} dynamics. The large difference in the ϕ production off C and W nuclei is discussed in terms of a strong ϕN in-medium coupling. These results are relevant for the description of heavy-ion collisions and the structure of neutron stars.

4.
Neuroscience ; 322: 489-99, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-26946265

RESUMO

Chronic stress is associated with a plethora of cognitive symptoms such as emotional dysregulation and impaired executive function that have been attributed to modifications in neuroanatomy in the orbitofrontal cortex (OFC), medial prefrontal cortex (mPFC), and hippocampus (HPC). While many studies have examined stress-induced changes in neuronal morphology, synaptic plasticity, and cellular function, there has been little investigation into persistent changes in gene expression that may be responsible for the maintenance of these changes. This study exposed adult rats to a chronic stressor and then examined changes in mRNA gene expression in the OFC, mPFC and HPC following a two-week withdrawal period. mRNA bio-sequencing results revealed sex- and region-dependent changes. Surprisingly the greatest changes in gene expression were found in the OFC, and similar to anatomical studies, analysis of gene changes with Ingenuity Pathway Analysis software demonstrated that the mPFC and OFC exhibited contrasting activation of canonical pathways and functional networks. The HPC demonstrated the largest degree of sex-dependent change in gene expression. In general, chronic stress induced persistent changes in gene expression in the three brain regions we examined and these changes could be associated with the commonly reported cognitive symptoms. The current study highlights the region- and sex-dependent nature of the brain's response to chronic stress and the difficulty we face when attempting to develop treatment options.


Assuntos
Metilação de DNA/fisiologia , Expressão Gênica/fisiologia , Hipocampo/metabolismo , Córtex Pré-Frontal/metabolismo , Estresse Psicológico/metabolismo , Animais , Doença Crônica , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Masculino , Distribuição Aleatória , Ratos Long-Evans , Caracteres Sexuais , Software , Estresse Psicológico/genética
5.
Ann Oncol ; 27(5): 902-7, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26787238

RESUMO

BACKGROUND: The IFM2009-02 trial studied pomalidomide (4 mg daily, 21/28 versus 28/28) and dexamethasone in very advanced relapsed or refractory multiple myeloma (RRMM). We observed that 40% of patients had a prolonged progression-free survival (PFS) and subsequently overall survival (OS). We sought to analyze the characteristics of these patients and study the effect of long exposure to pomalidomide. DESIGN: We separated the studied population into two groups: 3 months to 1 year (<1 year) and more than 1 year (≥1 year) of treatment with pomalidomide and dexamethasone based on clinical judgment and historical control studies. We then analyzed the characteristics of patients according to duration of treatment. RESULTS: The overall response rate (ORR) for the <1-year group was 43%, the median PFS 4.6 months [95% confidence interval (95% CI) 3.8-6.4] with only 6% at 12 months, and the median OS was 15 months (11.7-20.3) and 40% at 18 months. For the ≥1-year group, the response rate and survival were strikingly different, ORR at 83%, median PFS 20.7 months (14.7-35.4), median OS not reached, and 91% at 18 months. CONCLUSION: Pomalidomide and dexamethasone favored prolonged and safe exposure to treatment in 40% of heavily treated and end-stage RRMM, a paradigm shift in the natural history of RRMM characterized with a succession of shorter disease-free intervals and ultimately shorter survival. Although an optimization of pomalidomide-dexamethasone regimen is warranted in advanced RRMM, we claim that pomalidomide has proven once more to change the natural history of myeloma in this series, which should be confirmed in a larger study.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Talidomida/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bortezomib/administração & dosagem , Bortezomib/efeitos adversos , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Intervalo Livre de Doença , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Recidiva Local de Neoplasia/patologia , Talidomida/administração & dosagem , Talidomida/efeitos adversos
6.
Gesundheitswesen ; 78(12): 828-834, 2016 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-25806505

RESUMO

Objectives: Recently, the number of hospital report cards that compare quality of hospitals and present information from German quality reports has greatly increased. Objectives of this study were to a) identify suitable methods for measuring the readability and comprehensibility of hospital report cards, b) to obtain reliable information on the comprehensibility of texts for laymen, c) to give recommendations for improvements and d) to recommend public health actions. Methods: The readability and comprehensibility of the texts were tested with a) a computer-aided evaluation of formal text characteristics (readability indices Flesch (German formula) and 1. Wiener Sachtextformel formula), b) an expert-based heuristic analysis of readability and comprehensibility of texts (counting technical terms and analysis of text simplicity as well as brevity and conciseness using the Hamburg intelligibility model) and c) a survey of subjects about the comprehensibility of individual technical terms, the assessment of the comprehensibility of the presentations and the subjects' decisions in favour of one of the 5 presented clinics due to the better quality of data. In addition, the correlation between the results of the text analysis with the results from the survey of subjects was tested. Results: The assessment of texts with the computer-aided evaluations showed poor comprehensibility values. The assessment of text simplicity using the Hamburg intelligibility model showed poor comprehensibility values (-0.3). On average, 6.8% of the words used were technical terms. A review of 10 technical terms revealed that in all cases only a minority of respondents (from 4.4% to 39.1%) exactly knew what was meant by each of them. Most subjects (62.4%) also believed that unclear terms worsened their understanding of the information offered. The correlation analysis showed that presentations with a lower frequency of technical terms and better values for the text simplicity were better understood. Conclusion: The determination of the frequency of technical terms and the assessment of text simplicity using the Hamburg intelligibility model were suitable methods to determine the readability and comprehensibility of presentations of quality indicators. The analysis showed predominantly poor comprehensibility values and indicated the need to improve the texts of report cards.


Assuntos
Compreensão , Informação de Saúde ao Consumidor/classificação , Conhecimentos, Atitudes e Prática em Saúde , Hospitais/classificação , Disseminação de Informação , Garantia da Qualidade dos Cuidados de Saúde/classificação , Alemanha , Humanos , Vocabulário , Redação
7.
Nuklearmedizin ; 54(6): 241-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26388152

RESUMO

UNLABELLED: The aim was to analyze the degree of agreement between the central review panel and the local PET interpretation within the HD15 trial and its impact on subsequent treatment and progression free survival. PATIENTS, METHODS: The analysis set consisted of 739 patients with residues ≥ 2.5 cm after 6 or 8 cycles of BEACOPPesc from the HD15 trial performed by the German Hodgkin Study Group. The recommendation for or against further radiotherapy was based on the central [(18)F]FDG-PET interpretation. Central PET interpretation was compared to the local PET interpretation and concordance was measured using Cohen's Kappa coefficient. Prognostic impact of the analysis of concordance between local and central PET interpretations was evaluated using progression free survival (PFS); groups were compared with the log rank test. RESULTS: The central panel rated 548 of 739 patients (74%) as PET negative. Of these, 513 were also rated as PET negative in the local PET interpretation. PET positivity was seen by central reviewers in the remaining 191 patients (26%), in concordance with local reviewers in 155 cases. Even though substantial agreement was found (Cohen's Kappa 0.81), the interpretation of the central PET review panel led to a different therapeutic recommendation in 71/739 (10%) patients. PFS was equally high in groups in which the therapeutic regime had been changed on the basis of the central panel decision. CONCLUSION: High concordance is found between local and central reviewers with regard to PET interpretation in residual tissue after intense chemotherapy. The existence of the central PET review panel allows the identification of additional patients as PET negative so that radiotherapy can be safely omitted (35 of 548 patients = 4.7%).


Assuntos
Comitês Consultivos/estatística & dados numéricos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/tratamento farmacológico , Interpretação de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Monitoramento de Medicamentos , Europa (Continente)/epidemiologia , Doença de Hodgkin/epidemiologia , Humanos , Variações Dependentes do Observador , Prevalência , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade , Resultado do Tratamento
8.
Neuroscience ; 303: 200-10, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26149350

RESUMO

The goal of this research was to examine the effect of preconception paternal stress (PPS) on the subsequent neurodevelopment and behavior of male and female offspring. Prenatal (gestational) stress has been shown to alter brain morphology in the developing brain, and is presumed to be a factor in the development of some adult psychopathologies. Our hypothesis was that paternal stress in the preconception period could impact brain development in the offspring, leading to behavioral abnormalities later in life. The purpose of this study was to examine the effect of preconception paternal stress on developing male and female offspring brain morphology in five brain areas; medial prefrontal cortex (mPFC), orbitofrontal cortex (OFC), parietal cortex (Par1), hippocampus (CA1) and nucleus accumbens (NAc). Alterations in dendritic measures and spine density were observed in each brain area examined in paternal stress offspring. Our two main findings reveal; (1) PPS alters brain morphology and organization and these effects are different than the effects of stress observed at other ages; and, (2) the observed dendritic changes were sexually dimorphic. This study provides direct evidence that PPS modifies brain architecture in developing offspring, including dendritic length, cell complexity, and spine density. Alterations observed may contribute to the later development of psychopathologies and maladaptive behaviors in the offspring.


Assuntos
Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Dendritos/patologia , Estresse Psicológico/patologia , Animais , Epigênese Genética , Feminino , Masculino , Gravidez , Ratos , Ratos Long-Evans
9.
Phys Rev Lett ; 114(21): 212301, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-26066429

RESUMO

Results on the production of the double strange cascade hyperon Ξ^{-} are reported for collisions of p(3.5 GeV)+Nb, studied with the High Acceptance Di-Electron Spectrometer (HADES) at SIS18 at GSI Helmholtzzentrum for Heavy-Ion Research, Darmstadt. For the first time, subthreshold Ξ^{-} production is observed in proton-nucleus interactions. Assuming a Ξ^{-} phase-space distribution similar to that of Λ hyperons, the production probability amounts to P_{Ξ^{-}}=[2.0±0.4(stat)±0.3(norm)±0.6(syst)]×10^{-4} resulting in a Ξ^{-}/(Λ+Σ^{0}) ratio of P_{Ξ^{-}}/P_{Λ+Σ^{0}}=[1.2±0.3(stat)±0.4(syst)]×10^{-2}. Available model predictions are significantly lower than the measured Ξ^{-} yield.

10.
Neuroscience ; 288: 145-55, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-25555930

RESUMO

Apart from therapeutic discovery, the study of mild traumatic brain injury (mTBI) has been focused on two challenges: why do a majority of individuals recover with little concern, while a considerable proportion suffer with persistent and often debilitating symptomology; and, how do mild injuries significantly increase risk for an early-onset neurodegeneration? Owing to a lack of observable damage following mTBI, this study was designed to determine if there were changes in neuronal morphology, synaptic connectivity, and epigenetic patterning that could contribute to the manifestation of persistent neurological dysfunction. Prefrontal cortex tissue from male and female rats was used for Golgi-Cox analysis along with the profiling of changes in gene expression (BDNF, DNMT1, FGF2, IGF1, Nogo-A, OXYR, and TERT) and telomere length (TL), following a single mTBI or sham injury in the juvenile period. Golgi-Cox analysis of dendritic branch order, dendritic length, and spine density demonstrate that an early mTBI increases complexity of pyramidal neurons in the mPFC. Furthermore, there are also substantial changes in the expression levels of the seven genes of interest and TL following a single mild injury in this brain region. The results from the neuroanatomical measures and changes in gene expression indicate that the mTBI disrupts normal pruning processes that are typically underway at this point in development. In addition, there are significant interactions between the social environment and epigenetic processes that work in concert to perpetuate neurological dysfunction.


Assuntos
Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Córtex Pré-Frontal/patologia , Córtex Pré-Frontal/fisiopatologia , Animais , Dendritos/patologia , Dendritos/fisiologia , Modelos Animais de Doenças , Epigênese Genética/fisiologia , Feminino , Expressão Gênica/fisiologia , Perfilação da Expressão Gênica , Masculino , Córtex Pré-Frontal/crescimento & desenvolvimento , Células Piramidais/patologia , Células Piramidais/fisiopatologia , Ratos , Sinapses/patologia , Sinapses/fisiologia , Telômero/metabolismo , Telômero/patologia
11.
Behav Brain Res ; 282: 25-36, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25557797

RESUMO

Autism is a severe neurodevelopmental disorder with a population prevalence of 1 in 68, and dramatically increasing. While no single pharmacologic intervention has successfully targeted the core symptoms of autism, emerging evidence suggests that postnatal environmental manipulations may offer greater therapeutic efficacy. Massage therapy, or tactile stimulation (TS), early in life has repeatedly been shown to be an effective, low-cost, therapeutic approach in ameliorating the cognitive, social, and emotional symptoms of autism. While early TS treatment attenuates many of the behavioral aberrations among children with autism, the neuroanatomical correlates driving such changes are unknown. The present study assessed the therapeutic effects of early TS treatment on behavior and neuroanatomy using the valproic acid (VPA) rodent model of autism. Rats were prenatally exposed to VPA on gestational day 12.5 and received TS shortly following birth. Whereas TS reversed almost all the VPA-induced alterations in neuroanatomy, it failed to do so behaviorally. The TS VPA animals, when compared to VPA animals, did not exhibit altered or improved behavior in the delayed non-match-to-sample T-maze, Whishaw tray reaching, activity box, or elevated plus maze tasks. Anatomically, however, there were significant increases in dendritic branching and spine density in the medial prefrontal cortex, orbital frontal cortex, and amygdala in VPA animals following early TS treatment, suggesting a complete reversal or remediation of the VPA-induced effects in these regions. The results suggest that postnatal TS, during a critical period in development, acts as a powerful reorganization tool that can ameliorate the neuroanatomical consequences of prenatal VPA exposure.


Assuntos
Transtorno Autístico/patologia , Transtorno Autístico/terapia , Plasticidade Neuronal , Tato , Ácido Valproico/toxicidade , Tonsila do Cerebelo/patologia , Animais , Transtorno Autístico/induzido quimicamente , Transtorno Autístico/psicologia , Comportamento Animal , Dendritos/patologia , Espinhas Dendríticas/patologia , Modelos Animais de Doenças , Feminino , Lobo Frontal/patologia , Masculino , Aprendizagem em Labirinto , Atividade Motora , Córtex Pré-Frontal/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia , Efeitos Tardios da Exposição Pré-Natal/psicologia , Ratos , Ratos Long-Evans , Comportamento Social
12.
Behav Processes ; 106: 60-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24811452

RESUMO

During playful interactions, rats emit increased levels of 50-kHz vocalizations. It is possible that these vocalizations are used as play signals that promote and maintain playful contact. The study investigated this possibility. It was predicted that if these vocalizations are used as play signals, they should be more prevalent (1) before an attack, (2) in attacks leading to wrestling, and (3) in males compared to females, as males play more roughly. Moreover, given that there are at least 15 different subtypes of 50-kHz calls, it is possible that different calls are used in different contexts. Therefore, our prediction (4) was that different subtypes would be used for initiating and terminating playful contact. Pairs of same-sex juveniles were tested so that video recordings of their play and audio recordings of their vocalizations were synchronized. 50-kHz vocalizations occur more often before an attack and in male pairs. Specific calls were associated with specific types of behaviors and these associations differed between male and female rats. However, calls were not more frequent in attacks leading to wrestling than in attacks leading to withdrawal. The data provide qualified support for the hypothesis that 50-kHz vocalizations function as play signals.


Assuntos
Ratos/fisiologia , Comportamento Social , Vocalização Animal/fisiologia , Animais , Feminino , Masculino
13.
Dev Psychobiol ; 56(5): 1052-60, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24347393

RESUMO

Juvenile play experiences promote behavioral flexibility in rats. If other early positive experiences, such as tactile stimulation, are given prior to exposure to psychostimulants, the behavioral response to the drug is attenuated. The objective of the present study was to determine if the experience of juvenile play behavior would attenuate the response to nicotine. Two experiments were conducted: (1) behavioral sensitization to nicotine exposure, and (2) voluntary consumption of nicotine. For both experiments, rats were reared either with three same-sex peers (play group) or one adult (no play group) during their juvenile period. Then, as adults, half of each group was exposed to repeated injections of nicotine and the other half to saline. Prior play experience had no effect on behavioral sensitization or on voluntary consumption of nicotine. It remains to be determined whether juvenile experience with play influences the rewarding properties of nicotine in social contexts as adults.


Assuntos
Comportamento Animal/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/administração & dosagem , Atividade Motora/efeitos dos fármacos , Nicotina/administração & dosagem , Jogos e Brinquedos , Animais , Comportamento Animal/fisiologia , Relação Dose-Resposta a Droga , Feminino , Atividade Motora/fisiologia , Ratos , Recompensa , Autoadministração
14.
Transl Psychiatry ; 3: e338, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-24346136

RESUMO

Adolescence is a period of heightened susceptibility to psychiatric disorders of medial prefrontal cortex (mPFC) dysfunction and cognitive impairment. mPFC dopamine (DA) projections reach maturity only in early adulthood, when their control over cognition becomes fully functional. The mechanisms governing this protracted and unique development are unknown. Here we identify dcc as the first DA neuron gene to regulate mPFC connectivity during adolescence and dissect the mechanisms involved. Reduction or loss of dcc from DA neurons by Cre-lox recombination increased mPFC DA innervation. Underlying this was the presence of ectopic DA fibers that normally innervate non-cortical targets. Altered DA input changed the anatomy and electrophysiology of mPFC circuits, leading to enhanced cognitive flexibility. All phenotypes only emerged in adulthood. Using viral Cre, we demonstrated that dcc organizes mPFC wiring specifically during adolescence. Variations in DCC may determine differential predisposition to mPFC disorders in humans. Indeed, DCC expression is elevated in brains of antidepressant-free subjects who committed suicide.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Genes DCC/fisiologia , Transtornos Mentais/genética , Córtex Pré-Frontal/crescimento & desenvolvimento , Adolescente , Desenvolvimento do Adolescente/fisiologia , Animais , Estudos de Casos e Controles , Predisposição Genética para Doença , Haploinsuficiência , Humanos , Masculino , Camundongos , Vias Neurais/crescimento & desenvolvimento , Vias Neurais/metabolismo , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/metabolismo , Comportamento Autodestrutivo/genética , Suicídio
15.
Neurosci Lett ; 556: 42-5, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24103373

RESUMO

Juvenile play behavior in rats promotes later behavioral flexibility and appears to do so by modifying the neural systems that regulate the animal's response to unexpected challenges. For example, the experience of play has been shown to prune the dendritic arbor of the cells in the medial prefrontal cortex (mPFC), part of the brain's executive control system. The objective of the present study was to determine if the play-induced changes in the mPFC promotes greater plasticity to experiences later in life. In order to test this possibility, exposure to nicotine was used as the secondary experience given later in life, as it has been shown to produce later changes to the morphology of mPFC pyramidal neurons. Animals were either paired with three same-sex peers (play condition) or one adult (no play condition) during their juvenile period. As young adults, half of the rats from each condition were exposed to repeated injections of nicotine and the other half to injections of saline. The neural plasticity of the mPFC was measured by changes in length and branching of dendrites. Neural changes induced separately by play and by nicotine were consistent with previously published findings. The novel finding was that the cells in the mPFC exhibit a greater response to exposure to nicotine if the rats first had play experience. These findings suggest that juvenile play experiences enhance the plasticity of some neural systems.


Assuntos
Neurônios/ultraestrutura , Jogos e Brinquedos , Córtex Pré-Frontal/ultraestrutura , Envelhecimento/fisiologia , Animais , Dendritos/efeitos dos fármacos , Dendritos/ultraestrutura , Feminino , Plasticidade Neuronal , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Nicotina/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/crescimento & desenvolvimento , Ratos , Ratos Long-Evans
16.
Neuroscience ; 252: 178-89, 2013 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-23968593

RESUMO

Experience-dependent plasticity is an ongoing process that can be observed and measured at multiple levels. The first goal of this study was to examine the effects of prenatal nicotine on the performance of rats in three behavioral tasks (elevated plus maze (EPM), Morris water task (MWT), and Whishaw tray reaching). The second goal of this experiment sought to examine changes in dendritic organization following exposure to the behavioral training paradigm and/or low doses of prenatal nicotine. Female Long-Evans rats were administered daily injections of nicotine for the duration of pregnancy and their pups underwent a regimen of behavioral training in early adulthood (EPM, MWT, and Whishaw tray reaching). All offspring exposed to nicotine prenatally exhibited substantial increases in anxiety. Male offspring also showed increased efficiency in the Whishaw tray-reaching task and performed differently than the other groups in the probe trial of the MWT. Using Golgi-Cox staining we examined the dendritic organization of the medial and orbital prefrontal cortex as well as the nucleus accumbens. Participation in the behavioral training paradigm was associated with dramatic reorganization of dendritic morphology and spine density in all brain regions examined. Although both treatments (behavior training and prenatal nicotine exposure) markedly altered dendritic organization, the effects of the behavioral experience were much larger than those of the prenatal drug exposure, and in some cases interacted with the drug effects.


Assuntos
Dendritos/ultraestrutura , Aprendizagem/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Efeitos Tardios da Exposição Pré-Natal/patologia , Animais , Comportamento Animal/efeitos dos fármacos , Dendritos/efeitos dos fármacos , Feminino , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/patologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/patologia , Gravidez , Ratos , Ratos Long-Evans
17.
Eur J Neurosci ; 38(4): 2491-503, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23679187

RESUMO

This study examined changes in dendritic morphology and spine density in multiple brain regions [Zilles' areas: (i) the Cg3 region of the anterior cingulate cortex or the medial prefrontal cortex, layer III (Cg3); (ii) the dorsal agranular insular cortex, layer III (AID); (iii) the PAR I region of the parietal cortex, layer III (Par1) and (iv) the nucleus accumbens (NAc)]of Long-Evans rats following exposure to nicotine prenatally, in late adolescence, or both prenatally and in adolescence. Prenatal nicotine exposure induced enduring changes in neuroanatomical organisation that varied between male and female offspring, with males exhibiting increased dendritic complexity of neurons in AID and NAc whereas females experienced increased dendritic complexity in Par1 but decreased dendritic complexity of neurons in NAc. Similarly, nicotine given in late adolescence dramatically reorganised neural circuitry of both male and female offspring, with males exhibiting decreased dendritic complexity of neurons in Par1 and Cg3 but increased dendritic complexity in AID, and females exhibiting decreased dendritic complexity in Cg3 and NAc but increased complexity in AID. Exposure to nicotine both prenatally and in adolescence produced few neuroanatomical parameters that demonstrated a prenatal experience × adolescent drug administration interaction. Females showed additive effects in Par1, Cg3 and NAc whereas males demonstrated additive effects only in AID. Thus, the timing of nicotine exposure produced differential effects on cerebral organisation in a regionally specific manner.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/patologia , Nicotina/toxicidade , Efeitos Tardios da Exposição Pré-Natal/patologia , Animais , Encéfalo/crescimento & desenvolvimento , Feminino , Masculino , Modelos Animais , Gravidez , Ratos , Ratos Long-Evans
18.
Brain Res ; 1499: 53-60, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23328078

RESUMO

Prenatal exposure to nicotine has been associated with many long-term cognitive and behavioral abnormalities. Based upon these observable outcomes, we hypothesized that prenatal nicotine exposure would induce lasting changes in dendritic morphology and synaptic connectivity throughout the cortex. Pregnant Long-Evans rats were administered nicotine or saline for the duration of pregnancy and offspring were sacrificed at P100 for Golgi-Cox analysis (dendritic length, dendritic branching, and spine density) of the prefrontal cortex (AID and Cg3), parietal cortex, and nucleus accumbens. In male offspring dendritic branching increased in AID and NAc, but decreased in the apical field of Cg3; spine density increased everywhere except NAc where it decreased; and dendritic length was increased in Cg3(basilar) and NAc but reduced in PAR(basilar). In female offspring, dendritic branching increased in NAc but decreased in AID; spine density increased in AID and PAR but decreased in Cg3 and NAc, and dendritic length was reduced in Cg3, PAR, and NAc. As changes were identified at P100, prenatal exposure to nicotine dramatically reorganized neuroanatomy in a persistent manner, likely altering the brain's response to normal and abnormal experiences.


Assuntos
Córtex Cerebral/patologia , Espinhas Dendríticas/patologia , Nicotina/toxicidade , Agonistas Nicotínicos/toxicidade , Efeitos Tardios da Exposição Pré-Natal/patologia , Animais , Espinhas Dendríticas/efeitos dos fármacos , Feminino , Masculino , Gravidez , Ratos , Ratos Long-Evans
19.
Dev Neurosci ; 34(2-3): 268-76, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22890088

RESUMO

Autism is a highly debilitating disorder that has recently displayed a dramatic rise in incidence. In order to realistically study preventative and remedial strategies, it is important that we develop and understand useful animal models of the disorder. The purpose of this study was to investigate the efficacy of the prenatal valproic acid (VPA) rat model of autism by examining the neuro-anatomical and behavioural outcomes of offspring exposed to this paradigm. The VPA-treated rats exhibited behavioural changes in the delayed non-match-to-sample task, novel object recognition, activity box, and Whishaw tray reaching task. Anatomically, there was a reduction in brain weight and cortical thickness, along with decreased dendritic branching in the orbitofrontal cortex (OFC) and medial prefrontal cortex (mPFC), and decreased spine density in the mPFC, OFC, and cerebellum. Behavioural and anatomical findings from this study produced reliable results indicating that prenatal VPA exposure may be a viable model for the study of autism in rats.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , GABAérgicos/farmacologia , Efeitos Tardios da Exposição Pré-Natal , Ácido Valproico/farmacologia , Animais , Espinhas Dendríticas/efeitos dos fármacos , Feminino , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Gravidez , Ratos , Reconhecimento Psicológico/efeitos dos fármacos
20.
Neuroscience ; 216: 103-9, 2012 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-22542675

RESUMO

The long-term effects of stress during development have been well characterized. However, the effects of developmental stress on the underlying neurological mechanisms related to the reward system are not well understood. The present report studied the long term effects of stress during development on the structural plasticity in the cortical and subcortical regions. Rats exposed to stress during embryonic development (prenatal stress; PS) or soon after birth (maternal separation; MS) were studied for structural alteration at the neuronal level in the nucleus accumbens (NAc), orbital frontal cortex (OFC), and medial prefrontal cortex (mPFC). The findings show that stress during development increased dendritic branching, length, and spine density in the NAc, and subregions of the PFC. PS experience increased dendritic branching and length in the mPFC apical and basilar dendrites. In contrast, a PS-associated decrease in dendritic branching and length was observed in the basilar branches of the OFC. MS resulted in an increase in dendritic growth and spine density in the subregions of the PFC. The effect of PS on neuroanatomy was more robust than MS despite the shorter duration and intensity. The altered dendritic growth and spine density associated with stress during development could have potential impact on NAc and PFC related behaviors.


Assuntos
Espinhas Dendríticas , Hipocampo/citologia , Privação Materna , Núcleo Accumbens/citologia , Córtex Pré-Frontal/citologia , Estresse Fisiológico , Animais , Animais Recém-Nascidos , Feminino , Masculino , Plasticidade Neuronal/fisiologia , Gravidez , Ratos , Ratos Long-Evans
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