12 research outputs found

    Evidências e atualizações científicas sobre a Laparoscopia assistida por robô: Evidence and scientific updates on robot-assisted Laparoscopy

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    Um robô cirúrgico é um dispositivo controlado por computador que pode ser programado para auxiliar no posicionamento e manipulação de instrumentos cirúrgicos, o objetivo da cirurgia ginecológica robótica é usar uma abordagem minimamente invasiva para realizar procedimentos que geralmente são realizados por laparotomia ou são muito complexos para laparoscopia convencional ou cirurgiões iniciantes em cirurgia laparoscópica. As vantagens da laparoscopia robótica em relação à convencional incluem imagens tridimensionais, aprimoramento mecânico, estabilização de instrumentos dentro do campo cirúrgico e ergonomia aprimorada. A principal vantagem para o paciente é uma permanência hospitalar potencialmente mais curta e uma recuperação pós-operatória mais rápida e retorno à função plena. A laparoscopia convencional levou a melhorias notáveis ​​​​na cirurgia, no entanto, a ótica e a instrumentação são limitadas e o treinamento cirúrgico avançado é necessário para realizar procedimentos complexos. A laparoscopia assistida por robô possui recursos que superam as dificuldades da laparoscopia convencional e também podem introduzir novas opções cirúrgicas. No entanto, o custo é maior e o tempo operatório é tipicamente mais longo, principalmente quando o cirurgião está aprendendo a técnica, a fadiga do cirurgião é minimizada pelo uso de um console no qual o cirurgião pode sentar-se confortavelmente

    Resting-State Connectivity of the Left Frontal Cortex to the Default Mode and Dorsal Attention Network Supports Reserve in Mild Cognitive Impairment

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    Reserve refers to the phenomenon of relatively preserved cognition in disproportion to the extent of neuropathology, e.g., in Alzheimer’s disease. A putative functional neural substrate underlying reserve is global functional connectivity of the left lateral frontal cortex (LFC, Brodmann Area 6/44). Resting-state fMRI-assessed global LFC-connectivity is associated with protective factors (education) and better maintenance of memory in mild cognitive impairment (MCI). Since the LFC is a hub of the fronto-parietal control network that regulates the activity of other networks, the question arises whether LFC-connectivity to specific networks rather than the whole-brain may underlie reserve. We assessed resting-state fMRI in 24 MCI and 16 healthy controls (HC) and in an independent validation sample (23 MCI/32 HC). Seed-based LFC-connectivity to seven major resting-state networks (i.e., fronto-parietal, limbic, dorsal-attention, somatomotor, default-mode, ventral-attention, visual) was computed, reserve was quantified as residualized memory performance after accounting for age and hippocampal atrophy. In both samples of MCI, LFC-activity was anti-correlated with the default-mode network (DMN), but positively correlated with the dorsal-attention network (DAN). Greater education predicted stronger LFC-DMN-connectivity (anti-correlation) and LFC-DAN-connectivity. Stronger LFC-DMN and LFC-DAN-connectivity each predicted higher reserve, consistently in both MCI samples. No associations were detected for LFC-connectivity to other networks. These novel results extend our previous findings on global functional connectivity of the LFC, showing that LFC-connectivity specifically to the DAN and DMN, two core memory networks, enhances reserve in the memory domain in MCI

    Offset-related brain activity in the left ventrolateral prefrontal cortex promotes long-term memory formation of verbal events

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    Recent evidence suggests that brain activity following the offset of a stimulus during encoding contributes to long-term memory formation, however the exact mechanisms underlying offset-related encoding are still unclear. Here, in three transcranial magnetic stimulation studies (rTMS) we investigated offset-related activity in the left ventrolateral prefrontal cortex (VLPFC). rTMS was administered at different points in time around stimulus offset while participants encoded visually-presented words or pairs of words. The analyses focused on the effects of the stimulation on subsequent memory performance. rTMS administered at the offset of the stimuli, but not during online encoding, disrupted subsequent memory performance. In Experiment 1 we found that rTMS specifically disrupted encoding mechanisms initiated by the offset of the stimuli rather than general, post-stimulus processes. Experiment 2 showed that this effect was not dependent upon rTMS-induced somatosensory effects. In a third rTMS experiment we further demonstrated a robust decline in associative memory performance when the stimulation was delivered at the offset of the word pairs, suggesting that offset-related encoding may contribute to the binding of information into an episodic memory trace. The offset of the stimulus may represent an event boundary that promotes the reinstatement of the previously experienced event and episodic binding. [Abstract copyright: Copyright © 2021. Published by Elsevier Inc.

    Effects of transcranial magnetic stimulation on cognition in mild cognitive impairment. Double-blind, randomized controlled trial

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    INTRODUÇÃO: O envelhecimento está associado, muitas vezes, a um declínio cognitivo frequentemente negligenciado, especialmente quando em formas brandas e/ou iniciais, com importante repercussão na vida das pessoas. Tais declínios podem regredir para a normalidade, estabilizar ou mesmo evoluir para quadro demenciais. O comprometimento cognitivo leve (CCL) é uma síndrome clínica de associada a um risco aumentado de demência, podendo ter várias etiologias e patologias. Até o momento, não existe ainda uma abordagem terapêutica, deixando uma lacuna no arsenal terapêutico tanto do especialista quanto do clínico geral. A estimulação magnética transcraniana é uma técnica não invasiva e promissora. Tem potencial para melhorar a memória e a cognição de idosos ativando redes neurais. OBJETIVOS: Este trabalho visa verificar os efeitos da estimulação magnética transcraniana repetitiva (EMTr) de alta frequência primeiramente sobre a memória e, secundariamente, sobre a cognição global de idosos com CCL. MÉTODOS: Trata-se de um estudo duplo cego, randomizado sham-controlado. Foram estimulados 32 idosos com idades entre 60-74 anos, totalmente independentes para as atividades instrumentais de vida diária (AIVDs), com queixas subjetivas de memória e evidência de algum prejuízo na avaliação neuropsicológica, caracterizando CCL. Os participantes foram divididos em dois grupos: (I) EMTr ativa (n=15) e (II) EMTr sham (n=17). O grupo ativo recebeu 10 sessões de EMTr a 10Hz (110% do limiar motor e 2.000 pulsos por sessão) sobre o córtex pré-frontal dorso lateral esquerdo.Foi utilizada uma bobina inativa (sham) para o grupo placebo. As baterias neuropsicológicas foram realizadas nos três tempos: antes (T0), logo após (T1) e um mês após (T2) a EMTr. RESULTADOS: Dos 109 pacientes triados, 36 foram elegíveis para o estudo. Houve 4 desistências, e 32 finalizaram o estudo. Os dados demográficos foram homogêneos. Os escores dos testes foram ajustados para a idade e escolaridade. O ponto de corte do Escore Isquêmico de Hachinski foi <=4. A medida de desfecho primário foi o teste ecológico Rivermead Behavioural Memory (RBMT) devido a sua alta capacidade de predizer problemas de memória diárias. As variáveis contínuas foaram avaliadas pelo teste t de Student. Análise de variância para medidas repetidas (ANOVA) foi utilizada para comparar as medidas de variáveis quantitativas ao longo dos instantes de medição. Houve interação (efeito de grupo) a favor do grupo ativo nas variáveis Rivermead Behavioural Memory Test (p=0,042) e teste de Stroop (retângulos) (p=0,044) em T0-T1; dígitos ordem direta (p=0,041) e trilhas B em T1-T2 (p=0,032). Houve interação no teste de memória lógica tardia em T0-T1 e T0-T2 (p=0,044 e 0,005, respectivamente) a favor do grupo sham; porém, o desfecho foi igual em T2 em ambos os grupos. Não houve interação no IQCODE e na escala de Bayer de funcionalidade. Os resultados mostram melhora significativa, a um nível de 5% de significância, na memória do dia a dia, da atenção e de função executiva dos idosos que se submeteram à EMTr de alta frequência, sugerindo seu potencial terapêutico no CCL. Trial registration: clinicaltrials.gov Identifier: NCT01292382.BACKGROUND: Aging maybe associated with a cognitive decline often overlooked, especially in milder forms, with significant impact on people\'s lives. Such declines may regress to normal, or even stabilize, or progress to dementia. Mild cognitive impairment (MCI) is a clinical syndrome associated with an increased risk of dementia and may have different etiologies and pathologies. To date, there is still not a therapeutic approach, leaving a gap in the therapeutic armamentarium of both expert as the general practitioner. Transcranial magnetic stimulation is a promising and noninvasive technique with potential to improve memory and cognition in elderly by activating neural networks. OBJECTIVES: This study aims to assess the effects of high frequency repetitive transcranial magnetic stimulation (rTMS) primarily on memory and secondarily on global cognition in elderly people with MCI. METHODS: Double blind, randomized sham-controlled trial. Were stimulated 32 eldrely aged 60-74 years, totally independent for instrumental activities of daily living (IADL) with subjective memory complaints and evidence of some impairment in neuropsychological assessment, characterizing MCI. Subjects were divided into two groups: (I) active rTMS (n=15) and (II) rTMS sham (n=17). The active group received 10 sessions of 10 Hz rTMS (110% of motor threshold and 2000 pulses per session) over left dorsolateral prefrontal cortex. We used a inactive coil (sham) for the placebo group. The neuropsychological assessment were conducted in three stages: before (T0), immediately after (T1) and one month after (T2) rTMS. RESULTS: Of 109 patients screened, 36 were eligible for the study. There were 4 dropouts, and 32 completed the study. Demographic data were homogeneous. The test scores were adjusted for age and education. All subjects presented a cut-off score <=4 for the Hachinski Ischaemic Score. Continuous variables were evaluated by Student t test. Repeated measures of anayses of variance (ANOVA) were used to compare measures of quantitative variables along time. The primary outcome measure was a positive response on the ecological tool Rivermead Behavioural Memory Test (RBMT) because of its capacity to predict everyday memory problems. There was interaction (group effect) in favor of the active group over the variables RBMT (p=0.042) and Stroop test (colored rectangles) (p=0.044) at T0-T1; digit span direct order (p=0.041) and trail making B, T1-T2 (p=0.032). There was interaction in late logic memory test at T0-T1 and T0-T2 (p=0.044 and 0.005, respectively) for the sham group, but the outcome was the same in both groups at T2. There were no significant interaction at IQCODE and Bayer ADL Scale. The results present significant improvement, at a 5% level of significance, in everyday memory, attention and executive function of the elderly who underwent to high-frequency rTMS, suggesting its therapeutic potential in MCI. Trial registration: clinicaltrials.gov Identifier: NCT01292382

    Transcranial Magnetic Stimulation to Address Mild Cognitive Impairment in the Elderly: A Randomized Controlled Study

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    Transcranial magnetic stimulation (TMS) is a noninvasive brain stimulation technique with potential to improve memory. Mild cognitive impairment (MCI), which still lacks a specific therapy, is a clinical syndrome associated with increased risk of dementia. This study aims to assess the effects of high-frequency repetitive TMS (HF rTMS) on everyday memory of the elderly with MCI. We conducted a double-blinded randomized sham-controlled trial using rTMS over the left dorsolateral prefrontal cortex (DLPFC). Thirty-four elderly outpatients meeting Petersen’s MCI criteria were randomly assigned to receive 10 sessions of either active TMS or sham, 10 Hz rTMS at 110% of motor threshold, 2,000 pulses per session. Neuropsychological assessment at baseline, after the last session (10th) and at one-month follow-up, was applied. ANOVA on the primary efficacy measure, the Rivermead Behavioural Memory Test, revealed a significant group-by-time interaction p=0.05, favoring the active group. The improvement was kept after one month. Other neuropsychological tests were heterogeneous. rTMS at 10 Hz enhanced everyday memory in elderly with MCI after 10 sessions. These findings suggest that rTMS might be effective as a therapy for MCI and probably a tool to delay deterioration
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