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BACKGROUND: Several doubts remain regarding the optimal use of neoadjuvant imatinib in gastrointestinal stromal tumors (GISTs), such as ideal treatment duration, patient selection, and long-term survival outcomes. This manuscript provides a comprehensive review on neoadjuvant imatinib treatment outcomes and facilitate evidence-based decision-making for the use of imatinib therapy in GISTs. METHODS: Four databases (PubMed, EMBASE, Scopus, and Cochrane Library) were searched from inception to September 9, 2023. Meta-analyses of proportions were performed for the outcomes of R0 resection, disease responses, and 1-year, 3-year, and 5-year overall survival (OS) as well as 1-year, 3-year, and 5-year disease free survival (DFS). Sensitivity analyses in the form of leave-one-out analyses, meta-regression, and subgroup analyses were performed for outcomes with substantial statistical heterogeneity. RESULTS: The search yielded 1254 articles, and 36 studies were included in our analysis. Meta-analysis of proportions revealed that 1-year, 3-year, and 5-year OS was 100%, 94%, and 88%, while 1-year, 3-year and 5-year DFS was 99%, 89%, and 79%, respectively. An R0 resection rate of 89% and a disease response rate of 67% was achieved after a mean duration of treatment of 8.41 ± 0.367 months. KIT exon 9 mutation was significantly associated with poorer 5-year DFS. CONCLUSION: This study quantified key outcomes for neoadjuvant imatinib in locally advanced and metastatic or recurrent GIST. Patients with gastric and rectal tumous stand to benefit from neoadjuvant imatinib with an optimal treatment duration of 8 months. Furthermore, the potential utility of mutational analysis in guiding treatment with neoadjuvant imatinib was demonstrated.
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Antineoplásicos , Neoplasias Gastrointestinais , Tumores do Estroma Gastrointestinal , Mesilato de Imatinib , Terapia Neoadjuvante , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/mortalidade , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/genética , Mesilato de Imatinib/uso terapêutico , Humanos , Terapia Neoadjuvante/métodos , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/patologia , Neoplasias Gastrointestinais/mortalidade , Neoplasias Gastrointestinais/genética , Antineoplásicos/uso terapêutico , Resultado do TratamentoRESUMO
ABSTRACT: Due to the narrow window of opportunity for stroke therapeutics to be employed, effectiveness of stroke care systems is predicated on the efficiency of prehospital stroke systems. A robust prehospital stroke system of care that provides a rapid and well-coordinated response maximises favourable poststroke outcomes, but achieving this presents a unique set of challenges dependent on demographic and geographical circumstances. Set in the context of a highly urbanised first-world nation with a rising burden of stroke, Singapore's prehospital stroke system has evolved to reflect the environment in which it operates. This review aims to characterise the current state of prehospital stroke care in Singapore, covering prehospital aspects of the stroke survival chain from symptom onset till arrival at the emergency department. We identify areas for improvement and innovation, as well as provide insights into the possible future of prehospital stroke care in Singapore.
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BACKGROUND: Despite the increasing long-term survival after out-of-hospital cardiac arrest (OHCA), the risk of subsequent acute myocardial infarction (AMI) remains poorly understood. We aimed to determine the incidence, predictors, and long-term outcomes of AMI among survivors of OHCA. METHODS AND RESULTS: We assembled a retrospective cohort of 882 patients with OHCA who survived to 30 days or discharge from the hospital between 2010 and 2019. Survivors of OHCA had an increased risk of subsequent AMI, defined as AMI occurring 30 days after index OHCA or following discharge from the hospital after OHCA, compared with the general population when matched for age and sex (standardized incidence ratio, 4.64 [95% CI, 3.52-6.01]). Age-specific risks of subsequent AMI for men (standardized incidence ratio, 3.29 [95% CI, 2.39-4.42]) and women (standardized incidence ratio, 6.15 [95% CI, 3.27-10.52]) were significantly increased. A total of 7.2%, 8.3%, and 14.3% of survivors of OHCA had a subsequent AMI at 3 years, 5 years, and end of follow-up, respectively. Age at OHCA (hazard ratio [HR], 1.04 [95% CI, 1.02-1.06]) and past medical history of prior AMI, defined as any AMI preceding or during the index OHCA event (HR, 1.84 [95% CI, 1.05-3.22]), were associated with subsequent AMI, while an initial shockable rhythm was not (HR, 1.00 [95% CI, 0.52-1.94]). Survivors of OHCA with subsequent AMI had a higher risk of death (HR, 1.58 [95% CI, 1.12-2.22]) than those without. CONCLUSIONS: Survivors of OHCA are at an increased risk of subsequent AMI compared with the general population. Prior AMI, but not an initial shockable rhythm, increases this risk, while subsequent AMI predicts death. Preventive measures for AMI including cardiovascular risk factor control and revascularization may thus improve outcomes in selected patients with cardiac pathogenesis.
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Reanimação Cardiopulmonar , Infarto do Miocárdio , Parada Cardíaca Extra-Hospitalar , Masculino , Humanos , Feminino , Parada Cardíaca Extra-Hospitalar/epidemiologia , Parada Cardíaca Extra-Hospitalar/terapia , Parada Cardíaca Extra-Hospitalar/etiologia , Estudos Retrospectivos , Incidência , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/terapia , Infarto do Miocárdio/complicações , Sobreviventes , Reanimação Cardiopulmonar/efeitos adversosRESUMO
Previous research has shown greater risk aversion when people make choices about lives than cash. We tested the hypothesis that compared to placebo, exogenous testosterone administration would lead to riskier choices about cash than lives, given testosterone's association with financial risk-taking and reward sensitivity. A double-blind, placebo-controlled, randomized trial was conducted to test this hypothesis (Clinical Trials Registry: NCT02734238, www.clinicaltrials.gov). We collected functional magnetic resonance imaging (fMRI) data from 50 non-obese males before and shortly after 28 days of severe exercise-and-diet-induced energy deficit, during which testosterone (200 mg testosterone enanthate per week in sesame oil) or placebo (sesame seed oil only) was administered. Because we expected circulating testosterone levels to be reduced due to severe energy deficit, testosterone administration served a restorative function to mitigate the impact of energy deficit on testosterone levels. The fMRI task involved making choices under uncertainty for lives and cash. We also manipulated whether the outcomes were presented as gains or losses. Consistent with prospect theory, we observed the reflection effect such that participants were more risk averse when outcomes were presented as gains than losses. Brain activation in the thalamus covaried with individual differences in exhibiting the reflection effect. Testosterone did not impact choice, but it increased sensitivity to negative feedback following risky choices. These results suggest that exogenous testosterone administration in the context of energy deficit can impact some aspects of risky choice, and that individual differences in the reflection effect engage a brain structure involved in processing emotion, reward and risk.
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Jogo de Azar , Assunção de Riscos , Masculino , Humanos , Testosterona , Jogo de Azar/psicologia , Comportamento de Escolha/fisiologia , Encéfalo , Recompensa , Tomada de Decisões/fisiologiaRESUMO
BACKGROUND: Several measures of upper limb (UL) motor tasks have been developed to characterize recovery. However, UL performance and movement quality measures in isolation may not provide a true profile of functional recovery. OBJECTIVE: To investigate the measurement properties of a new trunk-based Index of Performance (IPt) of the UL combining endpoint performance (accuracy and speed) and movement quality (trunk displacement) in stroke. METHODS: Participants with stroke (n = 25, mean time since stroke: 18.7 ± 17.2 months) performed a reaching task over 3 evaluation sessions. The IPt was computed based on Fitts' Law that incorporated endpoint accuracy and speed corrected by the amount of trunk displacement. Test-retest reliability was analyzed using intraclass correlation coefficient (ICC) and Bland-Altman plots. Standard error of measurement (SEM) and Minimal Detectable Change (MDC) were determined. Validity was investigated through the relationship between IPt, Fugl-Meyer Assessment (FMA-UE), and Action Research Arm Test (ARAT), as well as the ability of IPt to distinguish between levels of UL motor impairment severity. RESULTS: Test-retest reliability was excellent (ICC = .908, 95% CI: 0.807-0.96). Bland-Altman did not show systematic differences. SEM and MDC95 were 14% and 39%, respectively. Construct validity was satisfactory. The IPt showed low-to-moderate relationships with FMA-UE (R2 ranged from .236 to .428) and ARAT (R2 ranged from .277 to .306). IPt scores distinguished between different levels of UL severity. CONCLUSIONS: The IPt showed evidence of good reliability, and initial validity. The IPt may be a promising tool for research and clinical settings. Further research is warranted to investigate its validity with additional comparator instruments.
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Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Psicometria , Recuperação de Função Fisiológica , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/diagnóstico , Extremidade Superior , TroncoRESUMO
Multitasking is a common requirement in many occupations. Considerable research has demonstrated that performance declines as a result of multitasking, and that it engages multiple brain regions. Despite growing evidence suggesting that brain regions operate as networks, minimal research has investigated the cognitive brain networks implicated in multitasking. The Multi-Attribute Task Battery II (MATB) is a common method for assessing multitasking ability that simulates a pilot's operational environment inside an aircraft cockpit. The aim of the present study was to examine multitasking performance on the MATB, and the associated neural patterns underlying performance with functional magnetic resonance imaging (fMRI). Twenty-four participants completed the MATB in the fMRI scanner. Participants completed four runs of the MATB in a 2 (Task: multitasking vs. single tasking) × 2 (Difficulty: hard vs. easy) design. MATB performance was measured as a function of accuracy. We analyzed the fMRI brain scans using both static and dynamic functional connectivity to determine whether there were differences in the connectivity patterns associated with each of the four conditions. A significant interaction between Task and Difficulty was observed such that multitasking performance accuracy, which was derived from the average across tasks, was lower than single tasking in the hard, but not easy, condition. The fMRI data revealed that static and dynamic functional connectivity between the default mode and dorsal attention networks was stronger during multitasking relative to single tasking. The static functional connectivity between the default mode and left frontoparietal networks, along with the dynamic functional connectivity between the dorsal attention and left frontoparietal networks, were both more anti-correlated during multitasking relative to single tasking. Taken together, the static and dynamic functional connectivity analyses provide complementary information to reveal the interactions among cognitive networks that support multitasking performance. Targeting these networks may offer a path to enhance multitasking ability through the application of neurostimulation and neuroenhancement techniques.
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Mapeamento Encefálico , Encéfalo , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Cognição/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Redes Neurais de Computação , Vias Neurais/fisiologiaRESUMO
AIMS: With a growing number of survivors of sudden cardiac arrest globally, their natural disease progression is of interest. This systematic review and meta-analysis aimed to determine the risk of recurrence after sudden cardiac arrest and its associated risk factors. METHODS: Medline, Embase, Cochrane Library and Scopus were searched from inception to October 2021. Studies involving survivors of an out-of-hospital sudden cardiac arrest event of any non-traumatic aetiology were included. Meta-analyses of proportions using the random-effects model estimated the primary outcome of first recurrent sudden cardiac arrest incidence as well as secondary outcomes including cumulative incidence of recurrence at 1-year and incidence of second recurrence among survivors of first recurrence. A recurrent episode was defined as a sudden cardiac arrest that occurs 28 or more days after the index event. Subgroup and meta-regression analyses were conducted for predetermined variables. The Newcastle-Ottawa Scale was used to assess risk of bias for most studies. RESULTS: 35 studies of moderate to high quality comprising a total of 7186 survivors were analysed. The pooled incidence of first recurrence was 15.24% (32 studies; 95%CI, 11.01-19.95; mean follow-up time, 41.3 ± 29.3 months) and second recurrence was 35.03% (3 studies; 95%CI, 19.65-51.93; mean follow-up time, 161.1 ± 54.3 months). At 1-year, incidence of recurrence was 10.62% (3 studies; 95%CI, 0.25-30.42). Subgroup analyses found no significant difference (p = 0.204) between incidence of first recurrence published from 1975-1992 and 1993-2021, and between studies with mean follow-up time of <24 months, 24-48 months, and >48 months. On meta-regression, initial shockable rhythm increased incidence of first recurrence (p = 0.01). CONCLUSION: 15.24% of sudden cardiac arrest survivors experienced a recurrence, and of these, 35.03% experienced a second recurrence. Most recurrences occurred in the first year. Initial shockable rhythm increased this risk. Despite the limitations of inter-study heterogeneity, these findings can still guide intervention and follow-up of sudden cardiac arrest survivors.
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Parada Cardíaca Extra-Hospitalar , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Humanos , Incidência , Parada Cardíaca Extra-Hospitalar/epidemiologia , Parada Cardíaca Extra-Hospitalar/etiologia , Parada Cardíaca Extra-Hospitalar/terapia , Fatores de Risco , SobreviventesRESUMO
We present a theoretical overview and experimental demonstration of a continuous-wave, cavity-enhanced optical absorption spectrometry method to detect molecular gas. This technique utilizes the two non-degenerate polarization modes of a birefringent cavity to obtain a zero background readout of the intra-cavity absorption. We use a double-pass equilateral triangle optical cavity design with additional feed-forward frequency noise correction to measure the R14e absorption line in the 30012â00001 band of CO2 at 1572.655 nm. We demonstrate a shot noise equivalent absorption of 3 × 10-13 cm-1 Hz-1/2.
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Traditionally, it has been assumed that logical thinking requires deliberation. However, people can also make logical responses quickly, exhibiting logical intuitions. We examined the neural correlates of logical intuitions by administering base rate problems during fMRI scanning using a two-response paradigm where participants first responded quickly and then reflectively to problems that did or did not pit a normative response against an intuitively-cued stereotypical response (i.e., conflict vs. non-conflict problems). As predicted, participants were less likely to make judgments in accordance with base rates on conflict problems. Critically, in only 4% of cases did longer deliberation change an initially biased response to a normatively correct response. The fMRI data revealed that intuitively-made initial biased judgments nevertheless activate regions typically involved in cognitive control, executive functions and attention, including anterior, inferior, middle and superior frontal cortex, suggesting that even when errors are made, there might be very early awareness of conflict.
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Imageamento por Ressonância Magnética , Pensamento , Sinais (Psicologia) , Lobo Frontal , Humanos , Pensamento/fisiologiaRESUMO
Divergent thinking tests have been used extensively in neuroscientific studies of creativity. However, output from tests of divergent thinking can be scored in different ways, and those scores can influence assessments of divergent thinking performance and its relationship with brain activation. Here we sought to investigate the relationship between various methods of scoring the Alternate Uses Task (AUT)-a well-known test of divergent thinking-and regional grey matter volume (GMV) using voxel-based morphometry (VBM). We assessed AUT performance based on (a) traditional approaches that involve scoring participants' output on fluency, flexibility, originality, and elaboration, (b) a subjective approach that involves scoring output directly on "snapshot" creativity, and (c) the definitional approach that involves scoring output separately on novelty and usefulness-the two criteria deemed necessary and jointly sufficient to categorize an idea as creative. Correcting for age, sex, intracranial volume, verbal IQ and working memory capacity, we found negative correlations between regional GMV in the left inferior temporal gyrus (ITG) and novelty and usefulness scores, but no correlation involving other scoring approaches. As part of the brain's core semantic system, this region is involved in concept retrieval and integration. We discuss the implications of these findings for our understanding of the neural bases of divergent thinking, and how ITG could be related to the generation of novel and useful responses.
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Encéfalo/anatomia & histologia , Testes Neuropsicológicos , Pensamento/fisiologia , Adulto , Criatividade , Feminino , Substância Cinzenta/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
INTRODUCTION: Damage to the corticospinal tract (CST) from stroke leads to motor deficits. The damage can be quantified as the amount of overlap between the stroke lesion and CST (CST Injury). Previous literature has shown that the degree of motor deficits post-stroke is related to the amount of CST Injury. These studies delineate the stroke lesion from structural T1-weighted magnetic resonance imaging (MRI) scans, often acquired for research. In Canada, computed tomography (CT) is the most common imaging modality used in routine acute stroke care. In this proof-of-principle study, we determine whether CST Injury, using lesions delineated from CT scans, significantly explains the variability in motor impairment in individuals with stroke. METHODS: Thirty-seven participants with stroke were included in this study. These individuals had a CT scan within the acute stage (7 days) of their stroke and underwent motor assessments. Brain images from CT scans were registered to MRI space. We performed a stepwise regression analysis to determine the contribution of CST injury and demographic variables in explaining motor impairment variability. RESULTS: Using clinically available CT scans, we found modest evidence that CST Injury explains variability in motor impairment (R2adj = 0.12, p = 0.02). None of the participant demographic variables entered the model. CONCLUSION: We show for the first time a relationship between CST Injury and motor impairment using CT scans. Further work is required to evaluate the utility of data derived from clinical CT scans as a biomarker of stroke motor recovery.
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Tratos Piramidais , Acidente Vascular Cerebral , Encéfalo , Humanos , Imageamento por Ressonância Magnética , Tratos Piramidais/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
Biomarkers that represent the structural and functional integrity of the motor system enable us to better assess motor outcome post-stroke. The degree of overlap between the stroke lesion and corticospinal tract (CST Injury) is a measure of the structural integrity of the motor system, whereas the left-to-right motor cortex resting state connectivity (LM1-RM1 rs-connectivity) is a measure of its functional integrity. CST Injury and LM1-RM1 rs-connectivity each individually correlate with motor outcome post-stroke, but less is understood about the relationship between these biomarkers. Thus, this study investigates the relationship between CST Injury and LM1-RM1 rs-connectivity, individually and together, with motor outcome. Twenty-seven participants with upper limb motor deficits post-stroke completed motor assessments and underwent MRI at one time point. CST Injury and LM1-RM1 rs-connectivity were derived from T1-weighted and resting state functional MRI scans, respectively. We performed hierarchical multiple regression analyses to determine the contribution of each biomarker in explaining motor outcome. The interaction between CST Injury and LM1-RM1 rs-connectivity does not significantly contribute to the variability in motor outcome. However, inclusion of both CST Injury and LM1-RM1 rs-connectivity explains more variability in motor outcome, than either alone. We suggest both biomarkers provide distinct information about an individual's motor outcome.
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Córtex Motor/fisiopatologia , Destreza Motora , Tratos Piramidais/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Conectoma , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Tratos Piramidais/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Extremidade Superior/inervação , Extremidade Superior/fisiopatologiaRESUMO
Movement is traditionally viewed as a process that involves motor brain regions. However, movement also implicates non-motor regions such as prefrontal and parietal cortex, regions whose integrity may thus be important for motor recovery after stroke. Importantly, focal brain damage can affect neural functioning within and between distinct brain networks implicated in the damage. The aim of this study is to investigate how resting state connectivity (rs-connectivity) within and between motor and frontoparietal networks are affected post-stroke in correlation with motor outcome. Twenty-seven participants with chronic stroke with unilateral upper limb deficits underwent motor assessments and magnetic resonance imaging. Participants completed the Chedoke-McMaster Stroke Assessment as a measure of arm (CMSA-Arm) and hand (CMSA-Hand) impairment and the Action Research Arm Test (ARAT) as a measure of motor function. We used a seed-based rs-connectivity approach defining the motor (seed=contralesional primary motor cortex (M1)) and frontoparietal (seed=contralesional dorsolateral prefrontal cortex (DLPFC)) networks. We analyzed the rs-connectivity within each network (intra-network connectivity) and between both networks (inter-network connectivity), and performed correlations between: a) intra-network connectivity and motor assessment scores; b) inter-network connectivity and motor assessment scores. We found: a) Participants with high rs-connectivity within the motor network (between M1 and supplementary motor area) have higher CMSA-Hand stage (z=3.62, p=0.003) and higher ARAT score (z=3.41, p=0.02). Rs-connectivity within the motor network was not significantly correlated with CMSA-Arm stage (z=1.83, p>0.05); b) Participants with high rs-connectivity within the frontoparietal network (between DLPFC and mid-ventrolateral prefrontal cortex) have higher CMSA-Hand stage (z=3.64, p=0.01). Rs-connectivity within the frontoparietal network was not significantly correlated with CMSA-Arm stage (z=0.93, p=0.03) or ARAT score (z=2.53, p=0.05); and c) Participants with high rs-connectivity between motor and frontoparietal networks have higher CMSA-Hand stage (rs=0.54, p=0.01) and higher ARAT score (rs=0.54, p=0.009). Rs-connectivity between the motor and frontoparietal networks was not significantly correlated with CMSA-Arm stage (rs=0.34, p=0.13). Taken together, the connectivity within and between the motor and frontoparietal networks correlate with motor outcome post-stroke. The integrity of these regions may be important for an individual's motor outcome. Motor-frontoparietal connectivity may be a potential biomarker of motor recovery post-stroke.
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Lobo Frontal/fisiopatologia , Mãos/fisiopatologia , Córtex Motor/fisiopatologia , Destreza Motora , Lobo Parietal/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Mapeamento Encefálico , Doença Crônica , Estudos Transversais , Avaliação da Deficiência , Feminino , Lobo Frontal/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Destreza Motora/fisiologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Lobo Parietal/diagnóstico por imagem , Estudo de Prova de Conceito , Recuperação de Função Fisiológica/fisiologia , Descanso , Acidente Vascular Cerebral/diagnóstico por imagemRESUMO
AIM: Intravenous vasodilators are often added to beta-blocking agents to reach blood pressure (BP) goals in aortic dissection. Control of BP using clevidipine has been described in hypertensive emergencies and cardiac surgery but not in aortic dissection. The aim of this study was to compare clevidipine versus sodium nitroprusside (SNP) as adjunct agents to esmolol for BP management in aortic dissection. METHODS: A single-center retrospective chart review evaluated patients diagnosed with aortic dissection. The primary outcome measure was time to reach patient specific systolic blood pressure (SBPPT) goals after initiation of esmolol infusion. Efficacy of clevidipine and SNP was assessed using area under the curve analysis of positive and negative excursions outside of SBPPT goals (AUCSBPe). Cost data was calculated using average wholesale price in U.S. dollars. RESULTS: Fourteen patients were included in final analyses. Median systolic BP immediately prior to initiation of esmolol was 162mm Hg vs 161mm Hg for clevidipine and SNP groups, respectively (p=0.99). Median time to reach SBPPT goal was similar between clevidipine and SNP (1.68 versus 1.03h [p=0.99]). Median AUCSBPe was similar for clevidipine and SNP (206.9 versus 538.9 mm Hg∗min∗hr-1 [p=0.11]). Cost was significantly reduced using clevidipine versus SNP ($1223.28/day versus $7674.24/day [p<0.001]). CONCLUSIONS: Clevidipine administration during initial medical management of aortic dissection showed similar efficacy compared to SNP when used as adjunct therapy to esmolol. These data suggest clevidipine is a less costly, reasonable alternative to SNP in acute aortic dissection as adjunct therapy to esmolol. Further studies are needed to validate these results.
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Aneurisma da Aorta Torácica/tratamento farmacológico , Dissecção Aórtica/tratamento farmacológico , Pressão Sanguínea/efeitos dos fármacos , Nitroprussiato/administração & dosagem , Piridinas/administração & dosagem , Doença Aguda , Idoso , Dissecção Aórtica/fisiopatologia , Aneurisma da Aorta Torácica/fisiopatologia , Bloqueadores dos Canais de Cálcio/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Vasodilatadores/administração & dosagemRESUMO
OBJECTIVE: To assess the prevalence of delirium and coma in mechanically ventilated patients sedated with dexmedetomidine or propofol alone; to evaluate the hospital length of stay for both treatment groups; and to evaluate the level of sedation, adverse effects, and hospital outcomes. METHODS: Medical records were reviewed retrospectively for patients who were admitted to the medical or surgical intensive care units (ICUs) in a 591-bed teaching hospital and who received either dexmedetomidine or propofol alone for 24 hours or more for sedation. RESULTS: A total of 111 patients were included in the study, with 56 patients in the dexmedetomidine group and 55 patients in the propofol group. Results of the analysis showed that the propofol group had a higher prevalence of coma (43.6% versus 12.5%; P < 0.001). Dexmedetomidine patients had a longer median hospital length of stay of 23.5 days (interquartile range [IQR], 11.5-39.5 days) versus 15.0 days (IQR, 7.0-24.0 days; P = 0.01). The rates of delirium were similar in both groups, with 16% in dexmedetomidine-treated patients versus 20% in propofol-treated patients (P = 0.63). CONCLUSION: No difference in the prevalence of delirium was found when comparing the dexmedetomidine- and propofol-treated groups. Propofol was associated with more coma and oversedation; dexmedetomidine was associated with longer time to extubation, longer length of stay in the ICU, and longer hospital length of stay.
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This experiment uses digital interferometry to reduce polarisation noise from a fiber interferometer to the level of double Rayleigh backscatter making precision fiber metrology systems robust for remote field applications. This is achieved with a measurement of the Jones matrix with interferometric sensitivity in real time, limited only by fibre length and processing bandwidth. This new approach leads to potentially new metrology applications and the ability to do ellipsometry without polarisation elements in the output field.
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We configure an all-fiber digital interferometer to eliminate both code noise and Rayleigh backscatter noise from bidirectional measurements. We utilize a sawtooth phase ramp to upconvert code noise beyond our signal bandwidth, demonstrating an in-band noise reduction of approximately two orders of magnitude. In addition, we demonstrate, for the first time to our knowledge, the use of relative code delays within a digital-interferometer system to eliminate Rayleigh-backscatter noise, resulting in a noise reduction of a factor of 50. Finally, we identify double Rayleigh-backscatter noise as our limiting noise source and suggest two methods to minimize this noise source.
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Embodied cognition holds that abstract concepts are grounded in perceptual-motor simulations. If a given embodied metaphor maps onto a spatial representation, then thinking of that concept should bias the allocation of attention. In this study, we used positive and negative self-esteem words to examine two properties of conceptual cueing. First, we tested the orientation-specificity hypothesis, which predicts that conceptual cues should selectively activate certain spatial axes (in this case, valenced self-esteem concepts should activate vertical space), instead of any spatial continuum. Second, we tested whether conceptual cueing requires semantic processing, or if it can be achieved with shallow visual processing of the cue words. Participants viewed centrally presented words consisting of high or low self-esteem traits (e.g., brave, timid) before detecting a target above or below the cue in the vertical condition, or on the left or right of the word in the horizontal condition. Participants were faster to detect targets when their location was compatible with the valence of the word cues, but only in the vertical condition. Moreover, this effect was observed when participants processed the semantics of the word, but not when processing its orthography. The results show that conceptual cueing by spatial metaphors is orientation-specific, and that an explicit consideration of the word cues' semantics is required for conceptual cueing to occur.