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1.
Zhen Ci Yan Jiu ; 45(1): 33-9, 2020 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-32144906

RESUMO

OBJECTIVE: To explore the effect of moxibustion of acupoints of Governor Vessel on learning-memory ability and expression of the receptor for advanced glycation end products (RAGE), low density lipoprotein (LDL) receptor related protein-1 (LRP-1), ß-amyloid precursor protein (APP) and neuronal ultrastructure of the frontal cortex and hippocampus in vascular dementia (VD) rats, so as to investigate its underlying mechanisms in relieving VD. METHODS: A total of 24 male SD rats were randomized into normal, model, and moxibustion groups (n=8 rats in each group). The VD model was established by occlusion of the bilateral common carotid arteries for 20 min and reperfusion for 10 min which was repeated for 3 times. Moxibustion was applied to "Baihui" (GV20), "Dazhui"(GV14) and "Fengfu"(GV16)for 30 min, once daily for 4 weeks. The learning-memory ability was evaluated by using Morris water maze tests. At the end of experiments, the frontal lobe of cerebral cortex and hippocampus tissues were collected for detecting the expression of RAGE and LRP-1 proteins with Western blot, and RAGE, LRP-1 and APP mRNAs with quantitative real-time PCR, respectively. The ultrastructure of neurons in the frontal cortex and hippocampal CA1 region was observed with transmission electron microscopy. RESULTS: Following modeling, Morris water maze tests showed that the average escape latency of the model group and moxibustion group was significantly prolonged on the 4th day of modeling (P<0.01). The expression levels of RAGE protein and mRNA and APP mRNA were significantly increased (P<0.01), while those of LRP-1 protein and mRNA in the cortex and hippocampus remarkably decreased in the model group relevant to the normal group (P<0.01). Following moxibustion, modeling-induced increase of expression of RAGE protein and mRNA and APP mRNA, and down-regulation of expression of LRP-1 protein and mRNA were reversed in the moxibustion group relevant to the model group (P<0.01). Results of electron microscopy showed dilation of the mitochondria with disappearance of the cristae, partial vacuolar degeneration or dissolved external membrane, and cytoplasmic edema with basic disappearance of the rough endoplasmic reticulum and glycogen particles in neurons of the frontal cortex and hippocampal CA1 region after modeling, which was relatively milder in the moxibustion group. CONCLUSION: Moxibustion of acupoints of the Governor Vessel may reduce the content of APP in the frontal cortex and hippocampus by regulating the expression of RAGE and LRP-1 proteins and mRNA in VD rats.


Assuntos
Demência Vascular , Moxibustão , Animais , Lobo Frontal , Hipocampo , Masculino , Neurônios , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada
2.
PLoS One ; 15(2): e0228541, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32069294

RESUMO

Switching between tasks requires individuals to inhibit mental representations of the previous task demands and to activate representations of the new task demands. The inhibition of the executed task remains active for a while so that when the inhibited task set must be re-activated shortly after, the need to overcome residual task set inhibition leads to behavioral costs. In a sham-controlled balanced-order within-subjects experimental design we investigated whether applying right anodal/left cathodal transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal or parietal cortex modulated the ability to overcome persistent task inhibition during task switching. Results showed that right anodal/left cathodal tDCS over the parietal cortex improves performance selectively when switching back to a recently inhibited task that requires previous inhibition to be overcome. Right Anodal/left cathodal tDCS over the prefrontal cortex improves performance during task switching in general, either when re-engaging in a inhibited task or when engaging in a non-inhibited task. Results suggest a different contribution of prefrontal and parietal regions to task switching, with parietal cortex being selectively involved in overcoming persistent task inhibition and prefrontal cortex being more generally involved in the control of task set during task switching.


Assuntos
Lobo Frontal/fisiologia , Inibição Psicológica , Lobo Parietal/fisiologia , Tempo de Reação/fisiologia , Análise e Desempenho de Tarefas , Estimulação Transcraniana por Corrente Contínua/métodos , Adaptação Fisiológica/fisiologia , Adulto , Eletrodos , Feminino , Lateralidade Funcional/fisiologia , Neuroimagem Funcional , Humanos , Masculino , Projetos de Pesquisa , Adulto Jovem
3.
PLoS One ; 15(1): e0227667, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978088

RESUMO

The apolipoprotein E gene (APOE) is the strongest genetic risk factor for late-onset Alzheimer's disease (AD), yet the expression of APOE is not clearly understood. For example, it is unclear whether AD patients have elevated or decreased APOE expression or why the correlation levels of APOE RNA and the ApoE protein differ across studies. Likewise, APOE has a single CpG island (CGI) that overlaps with its 3'-exon, and this CGI's effect is unknown. We previously reported that the APOE CGI is highly methylated in human postmortem brain (PMB) and that this methylation is altered in AD frontal lobe. In this study, we comprehensively characterized APOE RNA transcripts and correlated levels of RNA expression with DNA methylation levels across the APOE CGI. We discovered the presence of APOE circular RNA (circRNA) and found that circRNA and full-length mRNA each constitute approximately one third of the total APOE RNA, with truncated mRNAs likely constituting some of the missing fraction. All APOE RNA species demonstrated significantly higher expression in AD frontal lobe than in control frontal lobe. Furthermore, we observed a negative correlation between the levels of total APOE RNA and DNA methylation at the APOE CGI in the frontal lobe. When stratified by disease status, this correlation was strengthened in controls but not in AD. Our findings suggest a possible modified mechanism of gene action for APOE in AD that involves not only the protein isoforms but also an epigenetically regulated transcriptional program driven by DNA methylation in the APOE CGI.


Assuntos
Doença de Alzheimer/genética , Apolipoproteínas E/genética , Encéfalo/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Apolipoproteínas E/metabolismo , Autopsia , Estudos de Casos e Controles , Cerebelo/metabolismo , Ilhas de CpG , Metilação de DNA , Feminino , Lobo Frontal/metabolismo , Regulação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , RNA Circular/genética , RNA Circular/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
4.
Adv Exp Med Biol ; 1232: 69-75, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893396

RESUMO

We investigated the relationship between cerebral oxygenation (COX) and skin blood flow (SkBF) at the left frontal lobes of 10 healthy young men during progressive hypoxia (∼ -1 h at each of 21%, 18%, 15%, and 12% of inspired oxygen [FiO2]). Acute hypotension was manipulated by a thigh-cuff-release technique, where a pressure of 220 mmHg was applied at both thigh muscles for 3 min and the cuff was immediately released to induce acute hypotension. While the resting baseline for COX before the thigh-cuff release manipulation decreased gradually with the reduction of FiO2 (P < 0.05), the resting baseline for SkBF, mean arterial blood pressure (MAP), and cutaneous vascular conductance (CVC) were unaffected by FiO2 (P > 0.05). The acute hypotension that was induced by the thigh-cuff release decreased COX, SkBF, MAP, and CVC; thereafter, these values recovered toward their baseline values. During the hypotension phase, while the time to the nadir values for COX slowed progressively with reductions in FiO2 (P < 0.05), those for SkBF, MAP, and CVC were unaffected by FiO2 (P > 0.05). These results suggest that COX may not be associated with SkBF for the protocol or with the subjects in the present study.


Assuntos
Circulação Cerebrovascular , Lobo Frontal , Hipotensão , Pele , Adulto , Velocidade do Fluxo Sanguíneo , Lobo Frontal/fisiologia , Hemodinâmica , Humanos , Hipotensão/fisiopatologia , Masculino , Pele/irrigação sanguínea , Adulto Jovem
5.
Nat Commun ; 11(1): 246, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937764

RESUMO

Synaptic dysfunction is hypothesised to play a key role in schizophrenia pathogenesis, but this has not been tested directly in vivo.  Here, we investigated synaptic vesicle glycoprotein 2A (SV2A) levels and their relationship to symptoms and structural brain measures using [11C]UCB-J positron emission tomography in 18 patients with schizophrenia and 18 controls. We found significant group and group-by-region interaction effects on volume of distribution (VT). [11C]UCB-J VT was significantly lower in the frontal and anterior cingulate cortices in schizophrenia with large effect sizes (Cohen's d = 0.8-0.9), but there was no significant difference in the hippocampus. We also investigated the effects of antipsychotic drug administration on SV2A levels in Sprague-Dawley rats using western blotting, [3H]UCB-J autoradiography and immunostaining with confocal microscopy, finding no significant effects on any measure. These findings indicate that there are lower synaptic terminal protein levels in schizophrenia in vivo and that antipsychotic drug exposure is unlikely to account for them.


Assuntos
Antipsicóticos/uso terapêutico , Encéfalo/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Esquizofrenia/tratamento farmacológico , Esquizofrenia/metabolismo , Animais , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/metabolismo , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/metabolismo , Humanos , Masculino , Especificidade de Órgãos , Tomografia por Emissão de Pósitrons , Piridinas/metabolismo , Pirrolidinonas/metabolismo , Ratos , Ratos Sprague-Dawley , Esquizofrenia/diagnóstico por imagem
6.
World Neurosurg ; 133: 42-48, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31550542

RESUMO

BACKGROUND: Navigated transcranial magnetic stimulation (nTMS) is being used for different purposes in patients with brain tumors. However, the procedure requires a positive electrophysiological response. For patients with negative response in rest conditions, active motor threshold (AMT) may be used. However, sometimes it is difficult to obtain AMT measures owing to inability of the patient to sustain steady muscle contraction. Herein, we describe a simple method by using a hand dynamometer to obtain AMT measures during nTMS session. CASE DESCRIPTION: A woman aged 68 years underwent total removal of a right frontal lobe oligodendroglioma World Health Organization grade II 15 years ago. Cranial magnetic resonance imaging during follow-up revealed local recurrence. In the postoperative period, she developed left upper limb paresis. A postoperative nTMS session was performed for motor electrophysiological evaluation. However, using the standard technique for AMT measurement, the patient was unable to perform sustained muscle contraction as required. A hand dynamometer was used. It allowed sustained muscle contraction for AMT measurement. A counter force for the index finger flexion, the hand support to stabilize hand joints, and a numerical screen serving for both the examiner and the patient as a feedback parameter may explain the success obtained with this simple device. CONCLUSIONS: Although more studies are necessary to validate the method, the hand dynamometer should be considered for patients unable to sustain muscle contraction during AMT measurement.


Assuntos
Lobo Frontal/fisiopatologia , Córtex Motor/fisiopatologia , Contração Muscular/fisiologia , Dinamômetro de Força Muscular , Recidiva Local de Neoplasia/fisiopatologia , Oligodendroglioma/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Idoso , Mapeamento Encefálico , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/cirurgia , Humanos , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/cirurgia , Oligodendroglioma/diagnóstico por imagem , Oligodendroglioma/cirurgia
7.
World Neurosurg ; 133: 55, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31562962

RESUMO

Laughter has a major role in daily social interactions; consequently, its biologic bases have been previously studied. Nevertheless, its cerebral representation remains unclear. The most accepted hypothesis has postulated that laughter has 2 components: mirth, related to the temporal and frontal neocortical areas, and motor aspect, related to the limbic system and brainstem. Furthermore, in prior studies, laughter has been elicited during electric stimulation with depth electrodes in the supplementary motor area and the cingulum. This Video 1 reports resection of a right superior frontal gyrus diffuse astrocytoma (isocitrate dehydrogenase mutant, World Health Organization grade II) with awake intraoperative electric cortical and subcortical stimulation mapping. Diffusion tensor imaging (DTI) tractography, including all the tracts in relation to the tumor, was obtained preoperatively and postoperatively. Stimulation of the cingulum medially and inferiorly to the tumor elicited a patient's smile and laugh without mirth or merriment. Also, this point correlated with the reconstructed cingulum in the intraoperatively navigated DTI tractography. In conclusion, these findings support the anatomic subdivision of the laughter's mechanism and the role of the cingulum in its motor component. Furthermore, smiles and laughter could be useful functional landmarks to identify the cingulum during subcortical mapping. Although it remains unclear whether pursuing resection beyond this point would have caused permanent postoperative deficits, considering laughter's role in social interaction and other emotion-processing functions associated with the cingulum, in the future it could be potentially considered a functional limit of the resection of intrinsic tumors.


Assuntos
Astrocitoma/cirurgia , Neoplasias Encefálicas/cirurgia , Giro do Cíngulo/fisiopatologia , Riso/fisiologia , Sorriso/fisiologia , Astrocitoma/patologia , Astrocitoma/fisiopatologia , Mapeamento Encefálico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Estimulação Elétrica , Lobo Frontal/patologia , Lobo Frontal/fisiopatologia , Lobo Frontal/cirurgia , Humanos
8.
Anaesthesia ; 75(2): 196-201, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31788791

RESUMO

Mechanisms underlying loss of consciousness following propofol administration remain incompletely understood. The objective of this study was to compare frontal lobe electroencephalography activity and brainstem reflexes during intravenous induction of general anaesthesia, in patients receiving a typical bolus dose (fast infusion) of propofol compared with a slower infusion rate. We sought to determine whether brainstem suppression ('bottom-up') predominates over loss of cortical function ('top-down'). Sixteen ASA physical status-1 patients were randomly assigned to either a fast or slow propofol infusion group. Loss of consciousness and brainstem reflexes were assessed every 30 s by a neurologist blinded to treatment allocation. We performed a multitaper spectral analysis of all electroencephalography data obtained from each participant. Brainstem reflexes were present in all eight patients in the slow infusion group, while being absent in all patients in the fast infusion group, at the moment of loss of consciousness (p = 0.010). An increase in alpha band power was observed before loss of consciousness only in participants allocated to the slow infusion group. Alpha band power emerged several minutes after the loss of consciousness in participants allocated to the fast infusion group. Our results show a predominance of 'bottom-up' mechanisms during fast infusion rates and 'top-down' mechanisms during slow infusion rates. The underlying mechanisms by which propofol induces loss of consciousness are potentially influenced by the speed of infusion.


Assuntos
Anestésicos Intravenosos/administração & dosagem , Estado de Consciência/efeitos dos fármacos , Eletroencefalografia/métodos , Lobo Frontal/efeitos dos fármacos , Propofol/administração & dosagem , Adulto , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Fatores de Tempo , Adulto Jovem
9.
Brain Lang ; 200: 104710, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31739187

RESUMO

This study used voxel-based lesion-symptom mapping to examine the cortical and white matter regions associated with language production impairments in a sample of 63 preoperative tumour patients. We identified four cognitive functions considered crucial for spoken language production: semantic-to-lexical mapping (selecting the appropriate lexical label for the intended concept); phonological encoding (retrieving the word's phonological form); articulatory-motor planning (programming the articulatory motor movements); and goal-driven language selection (exerting top-down control over the words selected for production). Each participant received a score estimating their competence on each function. We then mapped the region(s) where pathology was significantly associated with low scores. For semantic-to-lexical mapping, the critical map encompassed portions of the left posterior middle and inferior temporal gyri, extending into posterior fusiform gyrus, overlapping substantially with the territory of the inferior longitudinal fasciculus. For phonological encoding, the map encompassed the left inferior parietal lobe and posterior middle temporal gyrus, overlapping with the territory of the inferior longitudinal and posterior arcuate fasciculi. For articulatory-motor planning, the map encompassed parts of the left frontal pole, frontal operculum, and inferior frontal gyrus, and overlapped with the territory of the frontal aslant tract. Finally, the map for goal-driven language selection encompassed the left frontal pole and the anterior cingulate cortex. We compare our findings with those from other neuropsychological samples, and conclude that the study of tumour patients offers evidence that complements that available from other populations.


Assuntos
Mapeamento Encefálico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Transtornos da Linguagem/patologia , Transtornos da Linguagem/fisiopatologia , Fala/fisiologia , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/complicações , Feminino , Lobo Frontal/patologia , Lobo Frontal/fisiopatologia , Humanos , Transtornos da Linguagem/complicações , Masculino , Pessoa de Meia-Idade , Semântica , Lobo Temporal/patologia , Lobo Temporal/fisiopatologia , Substância Branca/patologia , Substância Branca/fisiopatologia , Adulto Jovem
10.
Dev Sci ; 23(1): e12844, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31056844

RESUMO

Low socioeconomic status (SES) is associated with greater risk for symptoms of attention-deficit/hyperactivity disorder (ADHD). One mechanism through which SES may confer risk for ADHD is by influencing brain structure. Alterations to cortical thickness, surface area and subcortical volume have been associated with low SES and with the presence of ADHD across multiple studies. The current study examined whether cortical thickness, surface area or subcortical volume mediate the associations between SES and ADHD in youth 3-21 years old (N = 874) from the Pediatric Imaging, Neurocognition and Genetics Study. Freesurfer was used to estimate cortical thickness, surface area and subcortical volume from structural magnetic resonance imaging. Parents reported on demographics, family SES, ADHD diagnoses and the presence of child attention problems. Statistical mediation was assessed using a bootstrap resampling procedure. Controlling for parental ADHD, child age, gender, birth weight and scanner, children in low SES families were more likely to be in the ADHD group. Consistent with previous reports in this sample, low SES was associated with reduced surface area across the frontal lobe and reduced subcortical volume in the amygdala, cerebellum, hippocampus and basal ganglia. Of these regions, a significant indirect effect of SES on ADHD status through subcortical volume was observed for the left cerebellum (95% confidence interval: 0.004, 0.022), the right cerebellum (95% confidence interval: 0.006, 0.025), and the right caudate (95% confidence interval: 0.002, 0.022). Environmentally mediated changes in the cerebellum and the caudate may be neurodevelopmental mechanisms explaining elevated risk of ADHD in children in low SES families.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Encéfalo/ultraestrutura , Classe Social , Adolescente , Tonsila do Cerebelo/patologia , Encéfalo/anatomia & histologia , Encéfalo/patologia , Mapeamento Encefálico/métodos , Criança , Pré-Escolar , Feminino , Lobo Frontal/patologia , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Adulto Jovem
11.
Dev Sci ; 23(1): e12891, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31359565

RESUMO

Asymmetric patterns of frontal brain electrical activity reflect approach and avoidance tendencies, with stability of relative right activation associated with withdrawal emotions/motivation and left hemisphere activation linked with approach and positive affect. However, considerable shifts in approach/avoidance-related lateralization have been reported for children not targeted because of extreme temperament. In this study, dynamic effects of frontal electroencephalogram (EEG) power within and across hemispheres were examined throughout early childhood. Specifically, EEG indicators at 5, 10, 24, 36, 48, and 72 months-of-age (n = 410) were analyzed via a hybrid of difference score and panel design models, with baseline measures and subsequent time-to-time differences modeled as potentially influencing all subsequent amounts of time-to-time change (i.e., predictively saturated). Infant sex was considered as a moderator of dynamic developmental effects, with temperament attributes measured at 5 months examined as predictors of EEG hemisphere development. Overall, change in left and right frontal EEG power predicted declining subsequent change in the same hemisphere, with effects on the opposing neurobehavioral system enhancing later growth. Infant sex moderated the pattern of within and across-hemisphere effects, wherein for girls more prominent left hemisphere influences on the right hemisphere EEG changes were noted and right hemisphere effects were more salient for boys. Largely similar patterns of temperament prediction were observed for the left and the right EEG power changes, with limited sex differences in links between temperament and growth parameters. Results were interpreted in the context of comparable analyses using parietal power values, which provided evidence for unique frontal effects.


Assuntos
Eletroencefalografia/métodos , Lobo Frontal/fisiologia , Criança , Feminino , Lobo Frontal/crescimento & desenvolvimento , Humanos , Lactente , Masculino , Motivação , Caracteres Sexuais , Temperamento/fisiologia
12.
World Neurosurg ; 135: e447-e451, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31843723

RESUMO

BACKGROUND: Slit ventricles can be a challenging target during shunt catheter insertion. Traditionally, the frontal approach has been considered optimal for small ventricles. At this center, routine use of electromagnetic (EM) stereotactic guidance (Stealth, Medtronic, Dublin, Ireland) has enabled a parietooccipital (P-O) burr hole approach to the frontal horns. We compare shunt placement and revisions required for patients with slit ventricles who had shunts inserted via a P-O approach versus frontal shunt. METHODS: We studied a retrospective cohort of patients with slit ventricles and a ventricular shunt inserted using EM guidance between 2012 and 2018. Slitlike ventricles were defined as the widest point of the lateral ventricle <3 mm. Outcome measures included placement accuracy and survival using the Kaplan-Meier curve. Optimal final catheter tip location was considered to be the frontal horn of the ipsilateral lateral ventricle. RESULTS: Eighty-two patients (77 female, 5 male) aged 34.9 ± 10.8 years (mean ± standard deviation) had ventricular shunts inserted for idiopathic intracranial hypertension (n = 63), chiari/syrinx (n = 8), congenital (n = 10), and pseudomeningocele (n = 1). Of those identified, 35 had primary P-O shunts and 46 had frontal shunts. Overall, 94% of cases had the catheter tip sitting in the frontal horn. The P-O approach was just as accurate as the frontal approach. Eight P-O shunts and 9 frontal shunts required revision over a 60-month period. There was no significant different in shunt survival between the 2 approaches (P = 0.37). CONCLUSIONS: EM-guided placement has enabled the P-O approach to be as safe and with equivalent survival to frontal approach. The accuracy of shunt placement between the 2 approaches was similar.


Assuntos
Craniotomia/métodos , Derivação Ventriculoperitoneal/métodos , Adulto , Ventrículos Cerebrais/cirurgia , Feminino , Lobo Frontal/cirurgia , Humanos , Masculino , Lobo Occipital/cirurgia , Lobo Parietal/cirurgia , Resultado do Tratamento , Retroversão Uterina
13.
Synapse ; 74(1): e22130, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31449695

RESUMO

Due to the prevalence of depression in women, female rats may be a better models for antidepressant research than males. In male rats, fluoxetine inhibited the serotonin (5-hydroxytryptamine, 5-HT) transporter (SERT) which is reducing the immobility time in the repeated forced swimming test (rFST). The performance of female rats in this test is unknown. In this study, responses of male and female rats in the rFST under chronic treatment with fluoxetine and the function of SERT in their brains were examined. Wistar rats received oral fluoxetine (females: 0, 1, 2.5, or 5 mg kg-1  day-1 ; males: 0 or 2.5 mg kg-1  day-1 ; in sucrose 10%, 1.5 ml/rat) 1 hr before the test daily for 12 days over the course of the rFST. rFST consisted of a 15 min pretest followed by 5 min sessions of swimming at 1 (test), 7 (retest 1), and 14 (retest 2) days later. SERT functioning was assessed by ex vivo assays of the frontal cortex and hippocampus of rats. Fluoxetine reduced immobility time of males in the rFST while it failed to do so in females. In vitro treatment with fluoxetine inhibited the uptake of 5-HT of both sexes similarly, while in vivo chronic administration of fluoxetine failed to do so. In summary, rats responded to the chronic treatment with fluoxetine in a sexually dimorphic fashion during the rFST despite the functioning of SERT in their brains remaining equally unchanged. Hence, our data suggest that sexually dimorphic responses to fluoxetine in rFST may be unrelated to the function of SERT in rat brains.


Assuntos
Fluoxetina/farmacologia , Lobo Frontal/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Inibidores de Captação de Serotonina/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Lobo Frontal/metabolismo , Hipocampo/metabolismo , Masculino , Ratos , Ratos Wistar , Fatores Sexuais , Natação
14.
Am J Forensic Med Pathol ; 41(1): 70-74, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31850919

RESUMO

We present a case of a 22-year-old man who died unexpectedly after a seizure due to a previously undiagnosed calcifying pseudoneoplasm of the neuraxis (CAPNON). Calcifying pseudoneoplasm of the neuraxis is a rare entity, and this is, to our knowledge, the first described case of sudden death due to CAPNON. Sudden death due to undiagnosed central nervous system mass lesions is rare, and most cases are attributable to hemorrhage, hydrocephalus, or increased intracranial pressure due to mass effect. Seizure is a rare cause of sudden death due to central nervous system mass lesions. This case highlights that mass lesions may cause sudden death due to seizure, even without other pathologic evidence of a cause of death, such as hemorrhage or edema. Furthermore, benign, reactive, and low-grade mass lesions may cause sudden death due to seizure. Seizure should remain in the autopsy differential as a cause of death, even where there is no pathologically evident mechanism by which a mass lesion caused death.


Assuntos
Encefalopatias/patologia , Calcinose/patologia , Morte Súbita/etiologia , Encefalopatias/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/patologia , Humanos , Masculino , Convulsões/etiologia , Tomografia Computadorizada por Raios X , Substância Branca/patologia , Adulto Jovem
15.
Med. clín (Ed. impr.) ; 153(12): 441-445, dic. 2019. graf, tab
Artigo em Inglês | IBECS | ID: ibc-188453

RESUMO

Background: Moyamoya disease belongs to rare diseases which are arousing public awareness of its importance in China. In order to investigate the clinical features of inpatients diagnosed Moyamoya disease, the study was conducted to collect clinical information data of subjects on demographic information and clinical characteristics in Henan, China. Methods: The data of 198 cases of Moyamoya disease from 56 tertiary hospitals in Henan province from January 2003 to June 2015 were collected retrospectively. Analysis was performed based on demographic, clinical and radiological characteristics of the patients. Results: The mean onset age was 44.03±14.45 years old. Unilateral limb weakness (36.4%) was the most common physical examination. Primary clinical manifestation was headache and dizziness (50.3%). Cranial CT showed cerebral infarction was mainly located in the frontal lobe (27.4%). MRA and DSA showed lesions mainly located in the middle cerebral artery (30.3% and 18.7%). Conclusions: Clinical manifestations of Moyamoya disease varied. Early diagnosis was necessary to reduce the misdiagnosis rate of this disease. Symptoms, radiological characteristics, and lesion localization characteristics should be fully considered, especially for indicators with a certain onset age, headache and dizziness, lesion located in the frontal lobe of middle cerebral artery


Antecedentes: La enfermedad de moyamoya pertenece al grupo de afecciones raras cuya importancia está despertando la conciencia pública en China. Con el fin de investigar las características clínicas de los pacientes hospitalizados en Henan (China) diagnosticados con la enfermedad de moyamoya, se llevó a cabo este estudio para recopilar información clínica sobre los pacientes junto con información demográfica y características clínicas. Métodos: Se recogieron retrospectivamente datos de 198 casos de la enfermedad de moyamoya en 56 hospitales terciarios de la provincia de Henan entre enero de 2003 y junio de 2015. El análisis se realizó con base en las características demográficas, clínicas y radiológicas de los pacientes. Resultados: La edad media de inicio de la enfermedad era de 44,03±14,45 años. La debilidad unilateral de las extremidades (36,4%) fue el hallazgo más común en las exploraciones físicas y la manifestación clínica primaria fue la combinación de dolor de cabeza y mareos (50,3%). La tomografía craneal mostró que el infarto cerebral afectaba principalmente al lóbulo frontal (27,4%). La angiografía de resonancia magnética y la angiografía por sustracción digital mostraron lesiones ubicadas principalmente en la arteria cerebral media (30,3 y 18,7%, respectivamente). Conclusiones: Las manifestaciones clínicas de la enfermedad de moyamoya fueron muy variadas. El diagnóstico precoz resultó necesario para reducir la tasa de diagnósticos erróneos de esta enfermedad. Se deben considerar los síntomas, las características radiológicas y las características de ubicación en su totalidad, especialmente en el caso de indicadores con una edad específica de inicio, dolor de cabeza y mareos, o una lesión situada en el lóbulo frontal, en la arteria cerebral media


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Doença de Moyamoya/epidemiologia , Lobo Frontal/diagnóstico por imagem , Infarto Cerebral/complicações , Estudos Retrospectivos , Debilidade Muscular/complicações , Cefaleia/complicações , Angiografia Cerebral , Diagnóstico Precoce , China , Pressão Sanguínea , Inquéritos e Questionários
16.
Elife ; 82019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31845887

RESUMO

An intuitive understanding of physical objects and events is critical for successfully interacting with the world. Does the brain achieve this understanding by running simulations in a mental physics engine, which represents variables such as force and mass, or by analyzing patterns of motion without encoding underlying physical quantities? To investigate, we scanned participants with fMRI while they viewed videos of objects interacting in scenarios indicating their mass. Decoding analyses in brain regions previously implicated in intuitive physical inference revealed mass representations that generalized across variations in scenario, material, friction, and motion energy. These invariant representations were found during tasks without action planning, and tasks focusing on an orthogonal dimension (object color). Our results support an account of physical reasoning where abstract physical variables serve as inputs to a forward model of dynamics, akin to a physics engine, in parietal and frontal cortex.


Assuntos
Encéfalo/fisiologia , Compreensão/fisiologia , Lobo Frontal/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Córtex Visual/fisiologia , Adulto , Encéfalo/anatomia & histologia , Mapeamento Encefálico/métodos , Feminino , Lobo Frontal/anatomia & histologia , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Modelos Neurológicos , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Córtex Visual/anatomia & histologia , Adulto Jovem
17.
Elife ; 82019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31852580

RESUMO

The contribution of insular cortex to speech production remains unclear and controversial given diverse findings from functional neuroimaging and lesional data. To create a precise spatiotemporal map of insular activity, we performed a series of experiments: single-word articulations of varying complexity, non-speech orofacial movements and speech listening, in a cohort of 27 patients implanted with penetrating intracranial electrodes. The posterior insula was robustly active bilaterally, but after the onset of articulation, during listening to speech and during production of non-speech mouth movements. Preceding articulation there was very sparse activity, localized primarily to the frontal operculum rather than the insula. Posterior insular was active coincident with superior temporal gyrus but was more active for self-generated speech than external speech, the opposite of the superior temporal gyrus. These findings support the conclusion that the insula does not serve pre-articulatory preparatory roles.


Assuntos
Percepção Auditiva/fisiologia , Córtex Cerebral/anatomia & histologia , Lobo Frontal/anatomia & histologia , Fala/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
J Headache Pain ; 20(1): 103, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711415

RESUMO

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) manifests principally as a suite of cognitive impairments, particularly in the executive domain. Executive functioning requires the dynamic coordination of neural activity over large-scale networks. It remains unclear whether changes in resting-state brain functional network connectivity and regional homogeneities (ReHos) underly the mechanisms of executive dysfunction evident in CADASIL patients. METHODS: In this study, 22 CADASIL patients and 44 matched healthy controls underwent resting-state functional magnetic resonance imaging (fMRI). Independent component analysis (ICA) was used to measure functional brain network connectivity, and ReHos were calculated to evaluate local brain activities. We used seed-based functional connectivity (FC) analyses to determine whether dysfunctional areas (as defined by ReHos) exhibited abnormal FC with other brain areas. Relationships among the mean intra-network connectivity z-scores of dysfunctional areas within functional networks, and cognitive scores were evaluated using Pearson correlation analyses. RESULTS: Compared to the controls, CADASIL patients exhibited decreased intra-network connectivity within the bilateral lingual gyrus (LG) and the right cuneus (CU) (thus within the visual network [VIN)], and within the right precuneus (Pcu), inferior frontal gyrus (IFG), and precentral gyrus (thus within the frontal network [FRN]). Compared to the controls, patients also exhibited significantly lower ReHos in the right precuneus and cuneus (Pcu/CU), visual association cortex, calcarine gyri, posterior cingulate, limbic lobe, and weaker FC between the right Pcu/CU and the bilateral parahippocampal gyrus (PHG), and between the right Pcu/CU and the right postcentral gyrus. Notably, the mean connectivity z-scores of the bilateral LG and the right CU within the VIN were positively associated with compromised attention, calculation and delayed recall as revealed by tests of the various cognitive domains explored by the Mini-Mental State Examination. CONCLUSIONS: The decreases in intra-network connectivity within the VIN and FRN and reduced local brain activity in the posterior parietal area suggest that patients with CADASIL may exhibit dysfunctional visuomotor behaviors (a hallmark of executive function), and that all visual information processing, visuomotor planning, and movement execution may be affected.


Assuntos
Encéfalo/diagnóstico por imagem , CADASIL/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Função Executiva , Adulto , Encéfalo/fisiopatologia , CADASIL/fisiopatologia , CADASIL/psicologia , Estudos de Casos e Controles , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Cognição , Disfunção Cognitiva/psicologia , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Neuroimagem Funcional , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiopatologia , Descanso , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiopatologia
19.
J Headache Pain ; 20(1): 104, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711434

RESUMO

BACKGROUND: Functional connectivity (FC) has been used to investigate the pathophysiology of migraine. Accumulating evidence is pointing toward malfunctioning of brainstem structures, i.e., the red nucleus (RN) and substantia nigra (SN), as an important factor in migraine without aura (MwoA). We aimed to identify atypical FC between the RN and SN and other brain areas in patients with MwoA and to explore the association between RN and SN connectivity changes and performance on neuropsychological tests in these patients. METHODS: Resting-state functional magnetic resonance imaging (fMRI) data were obtained from 30 patients with MwoA and 22 age-, sex-, and years of education-matched healthy controls (HC). The FC of the brainstem structures was analyzed using a standard seed-based whole-brain correlation method. The results of the brainstem structure FC were assessed for correlations with other clinical features. RESULTS: Patients with MwoA exhibited reduced left RN-based FC with the left middle frontal gyrus, reduced right RN-based FC with the ipsilateral superior parietal lobe, and increased FC with the ipsilateral cerebellum. Additionally, patients with MwoA demonstrated significantly decreased right SN-based FC with the right postcentral gyrus, left parietal lobule, and left superior frontal gyrus. Hypo-connectivity between the right SN and right postcentral gyrus was negatively correlated with disease duration (r = - 0.506, P = 0.004). Additionally, increased connectivity of the right RN to the ipsilateral cerebellar lobes was positively correlated with the Headache Impact Test-6 scores (r = 0.437, P = 0.016). CONCLUSIONS: The present study suggested that patients with MwoA have disruption in their RN and SN resting-state networks, which are associated with specific clinical characteristics. The changes focus on the regions associated with cognitive evaluation, multisensory integration, and modulation of perception and pain, which may be associated with migraine production, feedback, and development. Taken together, these results may improve our understanding of the neuropathological mechanism of migraine.


Assuntos
Enxaqueca sem Aura/diagnóstico por imagem , Núcleo Rubro/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Tronco Encefálico/diagnóstico por imagem , Tronco Encefálico/fisiopatologia , Estudos de Casos e Controles , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Enxaqueca sem Aura/fisiopatologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Testes Neuropsicológicos , Dor/diagnóstico por imagem , Dor/fisiopatologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiopatologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Núcleo Rubro/fisiopatologia , Substância Negra/fisiopatologia
20.
PLoS Comput Biol ; 15(10): e1006667, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31609973

RESUMO

A fundamental and recurrent question in systems neuroscience is that of assessing what variables are encoded by a given population of neurons. Such assessments are often challenging because neurons in one brain area may encode multiple variables, and because neuronal representations might be categorical or non-categorical. These issues are particularly pertinent to the representation of decision variables in the orbitofrontal cortex (OFC)-an area implicated in economic choices. Here we present a new algorithm to assess whether a neuronal representation is categorical or non-categorical, and to identify the encoded variables if the representation is indeed categorical. The algorithm is based on two clustering procedures, one variable-independent and the other variable-based. The two partitions are then compared through adjusted mutual information. The present algorithm overcomes limitations of previous approaches and is widely applicable. We tested the algorithm on synthetic data and then used it to examine neuronal data recorded in the primate OFC during economic decisions. Confirming previous assessments, we found the neuronal representation in OFC to be categorical in nature. We also found that neurons in this area encode the value of individual offers, the binary choice outcome and the chosen value. In other words, during economic choice, neurons in the primate OFC encode decision variables in a categorical way.


Assuntos
Comportamento de Escolha/fisiologia , Biologia Computacional/métodos , Tomada de Decisões/fisiologia , Algoritmos , Animais , Análise por Conglomerados , Lobo Frontal/fisiologia , Macaca mulatta , Modelos Teóricos , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Recompensa
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