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1.
Psychol Methods ; 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37561486

RESUMO

Meta-analyses in the psychological sciences typically examine moderators that may explain heterogeneity in effect sizes. One of the most commonly examined moderators is gender. Overall, tests of gender as a moderator are rarely significant, which may be because effects rarely differ substantially between men and women. While this may be true in some cases, we also suggest that the lack of significant findings may be attributable to the way in which gender is examined as a meta-analytic moderator, such that detecting moderating effects is very unlikely even when such effects are substantial in magnitude. More specifically, we suggest that lack of between-primary study variance in gender composition makes it exceedingly difficult to detect moderation. That is, because primary studies tend to have similar male-to-female ratios, there is very little variance in gender composition between primaries, making it nearly impossible to detect between-study differences in the relationship of interest as a function of gender. In the present article, we report results from two studies: (a) a meta-meta-analysis in which we demonstrate the magnitude of this problem by computing the between-study variance in gender composition across 286 meta-analytic moderation tests from 50 meta-analyses, and (b) a Monte Carlo simulation study in which we show that this lack of variance results in near-zero moderator effects even when male-female differences in correlations are quite large. Our simulations are also used to show the value of single-gender studies for detecting moderating effects. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

2.
Plants (Basel) ; 12(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37570906

RESUMO

The production of blueberries for fresh and processed consumption is increasing globally and has more than doubled in the last decade. Blueberry is grown commercially across a variety of climates in over 30 countries. The major classes of plants utilized for the planting and breeding of new cultivars are highbush, lowbush, half-high, Rabbiteye, and Southern highbush. Plants can be propagated by cuttings or in vitro micropropagation techniques. In vitro propagation offers advantages for faster generation of a large number of disease-free plants independent of season. Labor costs for in vitro propagation can be reduced using new cultivation technology and automation. Here, we test and demonstrate successful culture conditions and medium compositions for in vitro initiation, multiplication, and rooting of the Southern highbush cultivar 'Blue Suede™' (Vaccinium hybrid).

3.
Hum Factors ; 65(4): 546-561, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-34348511

RESUMO

OBJECTIVE: Assess performance, trust, and visual attention during the monitoring of a near-perfect automated system. BACKGROUND: Research rarely attempts to assess performance, trust, and visual attention in near-perfect automated systems even though they will be relied on in high-stakes environments. METHODS: Seventy-three participants completed a 40-min supervisory control task where they monitored three search feeds. All search feeds were 100% reliable with the exception of two automation failures: one miss and one false alarm. Eye-tracking and subjective trust data were collected. RESULTS: Thirty-four percent of participants correctly identified the automation miss, and 67% correctly identified the automation false alarm. Subjective trust increased when participants did not detect the automation failures and decreased when they did. Participants who detected the false alarm had a more complex scan pattern in the 2 min centered around the automation failure compared with those who did not. Additionally, those who detected the failures had longer dwell times in and transitioned to the center sensor feed significantly more often. CONCLUSION: Not only does this work highlight the limitations of the human when monitoring near-perfect automated systems, it begins to quantify the subjective experience and attentional cost of the human. It further emphasizes the need to (1) reevaluate the role of the operator in future high-stakes environments and (2) understand the human on an individual level and actively design for the given individual when working with near-perfect automated systems. APPLICATION: Multiple operator-level measures should be collected in real-time in order to monitor an operator's state and leverage real-time, individualized assistance.


Assuntos
Análise e Desempenho de Tarefas , Confiança , Humanos , Automação , Idioma , Sistemas Homem-Máquina
4.
Blood Adv ; 6(8): 2453-2465, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-34933342

RESUMO

Shear-induced platelet aggregation (SIPA) occurs under elevated shear rates (10 000 s-1) found in stenotic coronary and carotid arteries. The pathologically high shear environment can lead to occlusive thrombosis by SIPA from the interaction of nonactivated platelets and von Willebrand factor (VWF) via glycoprotein Ib-A1 binding. This process under high shear rates is difficult to visualize experimentally with concurrent molecular- and cellular-resolutions. To understand this fast bonding, we employ a validated multiscale in silico model incorporating measured molecular kinetics and a thrombosis-on-a-chip device to delineate the flow-mediated biophysics of VWF and platelets assembly into mural microthrombi. We show that SIPA begins with VWF elongation, followed by agglomeration of platelets in the flow by soluble VWF entanglement before mural capture of the agglomerate by immobilized VWF. The entire SIPA process occurs on the order of 10 milliseconds with the agglomerate traveling a lag distance of a few hundred microns before capture, matching in vitro results. Increasing soluble VWF concentration by ∼20 times in silico leads to a ∼2 to 3 times increase in SIPA rates, matching the increase in occlusion rates found in vitro. The morphology of mural aggregates is primarily controlled by VWF molecular weight (length), where normal-length VWF leads to cluster or elongated aggregates and ultra-long VWF leads to loose aggregates seen by others' experiments. Finally, we present phase diagrams of SIPA, which provides biomechanistic rationales for a variety of thrombotic and hemostatic events in terms of platelet agglomeration and capture.


Assuntos
Agregação Plaquetária , Trombose , Plaquetas/metabolismo , Humanos , Estresse Mecânico , Fator de von Willebrand/metabolismo
6.
J Biomech ; 120: 110349, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33711601

RESUMO

Occlusive thrombosis in arteries causes heart attacks and strokes. The rapid growth of thrombus at elevated shear rates (~10,000 1/s) relies on shear-induced platelet aggregation (SIPA) thought to come about from the entanglement of von Willebrand factor (VWF) molecules. The mechanism for SIPA is not yet understood in terms of cell- and molecule-level dynamics in fast flowing bloodstreams. Towards this end, we develop a multiscale computational model to recreate SIPA in silico, where the suspension dynamics and interactions of individual platelets and VWF multimers are resolved directly. The platelet-VWF interaction via GP1b-A1 bonds is prescribed with intrinsic binding rates theoretically derived and informed by single-molecule measurements. The model is validated against existing microfluidic SIPA experiments, showing good agreement with the in vitro observations in terms of the morphology, traveling distance and capture time of the platelet aggregates. Particularly, the capture of aggregates can occur in a few milliseconds, comparable to the platelet transit time through pathologic arterial stenotic sections and much shorter than the time for shear-induced platelet activation. The multiscale SIPA simulator provides a cross-scale tool for exploring the biophysical mechanisms of SIPA in silico that are difficult to access with single-molecule measurements or micro-/macro-fluidic assays only.


Assuntos
Agregação Plaquetária , Trombose , Biofísica , Plaquetas , Simulação por Computador , Humanos , Estresse Mecânico
7.
Phys Rev E ; 102(1-1): 013310, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32795082

RESUMO

Blood flowing through microvascular bifurcations has been an active research topic for many decades, while the partitioning pattern of nanoscale solutes in the blood remains relatively unexplored. Here we demonstrate a multiscale computational framework for direct numerical simulation of the nanoparticle (NP) partitioning through physiologically relevant vascular bifurcations in the presence of red blood cells (RBCs). The computational framework is established by embedding a particulate suspension inflow-outflow boundary condition into a multiscale blood flow solver. The computational framework is verified by recovering a tubular blood flow without a bifurcation and validated against the experimental measurement of an intravital bifurcation flow. The classic Zweifach-Fung (ZF) effect is shown to be well captured by the method. Moreover, we observe that NPs exhibit a ZF-like heterogeneous partition in response to the heterogeneous partition of the RBC phase. The NP partitioning prioritizes the high-flow-rate daughter branch except for extreme (large or small) suspension flow partition ratios under which the complete phase separation tends to occur. By analyzing the flow field and the particle trajectories, we show that the ZF-like heterogeneity in the NP partition can be explained by the RBC-entrainment effect caused by the deviation of the flow separatrix preceded by the tank treading of RBCs near the bifurcation junction. The recovery of homogeneity in the NP partition under extreme flow partition ratios is due to the plasma skimming of NPs in the cell-free layer. These findings, based on the multiscale computational framework, provide biophysical insights to the heterogeneous distribution of NPs in microvascular beds that are observed pathophysiologically.


Assuntos
Eritrócitos/metabolismo , Microvasos/metabolismo , Modelos Biológicos , Nanopartículas , Hemodinâmica , Cinética
8.
Neurocrit Care ; 32(3): 707-714, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32253732

RESUMO

BACKGROUND/OBJECTIVE: Intravenous nicardipine infusion is effective for rapid blood pressure control. However, its use requires hemodynamic monitoring in the intensive care unit (ICU) and is associated with high hospital cost. This study aimed to examine the effect of early versus late initiation of oral antihypertensives on ICU length of stay (LOS) and cost of hospitalization in patients with hypertensive intracerebral hemorrhage (ICH). METHODS: This is a single-center retrospective study of patients with hypertensive ICH treated with nicardipine infusion from January 1, 2013, to December 31, 2017. Patients were dichotomized into study and control groups, based on receiving oral antihypertensives within 24 h versus after 24 h of emergency department arrival. Baseline characteristics, duration of nicardipine infusion, LOS in the ICU and hospital, functional outcome at discharge, and hospital cost were compared between the two groups using univariate and multivariate analysis. RESULTS: A total of 90 patients in the study group and 76 in the control group were identified. There was no significant difference in demographics, past medical history, and initial SBP between the two groups. After adjusting for confounding factors with multivariate regression models, early initiation of oral antihypertensives was associated with significant reductions in duration of nicardipine infusion (55.5 ± 60.1 vs 121.6 ± 141.3 h, p <0.005), nicardipine cost ($14,207 vs $29,299, p < 0.01), ICU LOS (2 vs 5 days, p < 0.005), and cost of hospitalization ($24,564 vs $47,366, p < 0.01). There was no significant difference in adversary renal events, favorable outcomes, and mortality between the two groups. CONCLUSIONS: Early initiation of oral antihypertensives is safe and may have a significant financial impact on patients with hypertensive ICH.


Assuntos
Anti-Hipertensivos/administração & dosagem , Custos Hospitalares/estatística & dados numéricos , Hipertensão/tratamento farmacológico , Unidades de Terapia Intensiva , Hemorragia Intracraniana Hipertensiva/tratamento farmacológico , Tempo de Internação/estatística & dados numéricos , Nicardipino/uso terapêutico , Administração Oral , Idoso , Anti-Hipertensivos/uso terapêutico , Intervenção Médica Precoce , Feminino , Estado Funcional , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Nicardipino/economia , Resultado do Tratamento
9.
Ann Biomed Eng ; 47(12): 2516, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31686309

RESUMO

This erratum is to correct the heading of column 2 (titled "b") in Table 1, which was missing proper units. The heading for that column was revised to include proper units, reading "b (× 10-6 s)".

10.
Ergonomics ; 62(9): 1150-1161, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31179874

RESUMO

The goal of this research was to determine how individuals perform and allocate their visual attention when monitoring multiple automated displays that differ in automation reliability. Ninety-six participants completed a simulated supervisory control task where each automated display had a different level of reliability (namely 70%, 85% and 95%). In addition, participants completed a high and low workload condition. The performance data revealed that (1) participants' failed to detect automation misses approximately 2.5 times more than automation false alarms, (2) participants' had worse automation failure detection in the high workload condition and (3) participant automation failure detection remained mostly static across reliability. The eye tracking data revealed that participants spread their attention relatively equally across all three of the automated displays for the duration of the experiment. Together, these data support a system-wide trust approach as the default position of an individual monitoring multiple automated displays. Practitioner Summary: Given the rapid growth of automation throughout the workforce, there is an immediate need to better understand how humans monitor multiple automated displays concurrently. The data in this experiment support a system-wide trust approach as the default position of an individual monitoring multiple automated displays. Abbreviations: DoD: Department of Defense; UA: unmanned aircraft; SCOUT: Supervisory Control Operations User Testbed; UAV: unmanned aerial vehicle; AOI: areas of interest.


Assuntos
Atenção , Terminais de Computador , Falha de Equipamento , Análise e Desempenho de Tarefas , Carga de Trabalho/psicologia , Aeronaves/instrumentação , Automação , Aviação , Simulação por Computador , Movimentos Oculares , Feminino , Humanos , Masculino , Confiança/psicologia , Adulto Jovem
11.
Ann Intern Med ; 169(12): 855-865, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30422263

RESUMO

Background: Many low-risk patients with acute pulmonary embolism (PE) in the emergency department (ED) are eligible for outpatient care but are hospitalized nonetheless. One impediment to home discharge is the difficulty of identifying which patients can safely forgo hospitalization. Objective: To evaluate the effect of an integrated electronic clinical decision support system (CDSS) to facilitate risk stratification and decision making at the site of care for patients with acute PE. Design: Controlled pragmatic trial. (ClinicalTrials.gov: NCT03601676). Setting: All 21 community EDs of an integrated health care delivery system (Kaiser Permanente Northern California). Patients: Adult ED patients with acute PE. Intervention: Ten intervention sites selected by convenience received a multidimensional technology and education intervention at month 9 of a 16-month study period (January 2014 to April 2015); the remaining 11 sites served as concurrent controls. Measurements: The primary outcome was discharge to home from either the ED or a short-term (<24-hour) outpatient observation unit based in the ED. Adverse outcomes included return visits for PE-related symptoms within 5 days and recurrent venous thromboembolism, major hemorrhage, and all-cause mortality within 30 days. A difference-in-differences approach was used to compare pre-post changes at intervention versus control sites, with adjustment for demographic and clinical characteristics. Results: Among 881 eligible patients diagnosed with PE at intervention sites and 822 at control sites, adjusted home discharge increased at intervention sites (17.4% pre- to 28.0% postintervention) without a concurrent increase at control sites (15.1% pre- and 14.5% postintervention). The difference-in-differences comparison was 11.3 percentage points (95% CI, 3.0 to 19.5 percentage points; P = 0.007). No increases were seen in 5-day return visits related to PE or in 30-day major adverse outcomes associated with CDSS implementation. Limitation: Lack of random allocation. Conclusion: Implementation and structured promotion of a CDSS to aid physicians in site-of-care decision making for ED patients with acute PE safely increased outpatient management. Primary Funding Source: Garfield Memorial National Research Fund and The Permanente Medical Group Delivery Science and Physician Researcher Programs.


Assuntos
Assistência Ambulatorial/métodos , Tomada de Decisão Clínica , Sistemas de Apoio a Decisões Clínicas , Serviço Hospitalar de Emergência/organização & administração , Embolia Pulmonar/terapia , Idoso , California , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Embolia Pulmonar/complicações , Recidiva , Medição de Risco/métodos , Resultado do Tratamento
12.
In Vitro Cell Dev Biol Plant ; 54(6): 612-620, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30459490

RESUMO

Somatic embryogenesis offers many benefits for clonal propagation in large-scale plant production of conifers. A key rate-limiting step is the conversion from early-stage somatic embryos in pro-embryogenic masses (PEMs) to the maturation stage. Immature embryos in PEMs are present at different developmental stages, where some are unable to respond to the maturation treatment, thus limiting yields of mature embryos. Synchronization of early somatic embryo development in PEMs could greatly improve subsequent yields of mature embryos. A temporary immersion bioreactor designed for Norway spruce (Picea abies (L.) H.Karst.) was used in this study. Through a specific system for dispersion, connected tissue of PEMs, composed of immature embryos grown in liquid medium in the temporary immersion bioreactors or on solid medium as a control, was dispersed and redistributed in a more uniform spatial arrangement. It was demonstrated that development of mature embryos could be significantly stimulated by dispersion, compared to controls, in both medium types. Synchronization of maturation was evaluated by a statistical approach. The present study shows that the yield of mature embryos from dispersed PEMs was three to five times higher than that from non-dispersed controls in three of four cell lines of Norway spruce tested, both in bioreactors and on solid medium.

13.
Biomicrofluidics ; 12(4): 042210, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29887934

RESUMO

Platelet accumulation under high shear rates at the site of atherosclerotic plaque rupture leads to myocardial infarction and stroke. Current antiplatelet therapies remain ineffective within a large percentage of the population, while presenting significant risks for bleeding. We explore a novel way to inhibit arterial thrombus formation by biophysical means without the use of platelet inactivating drugs. Our computational multi-scale dynamics model has predicted that charged particles of a specific size may entangle von Willebrand Factor (vWF) polymers and reduce the amount of elongation at high shear rates. We tested this hypothesis experimentally for negatively charged nanoparticles (CNP) to inhibit arterial thrombus formation. CNP of a particular size and charge inhibited thrombus formation, with a 10-fold peak inhibition over control conditions of thrombotic occlusion. Particles of differing material composition, size, and charge had little effect as predicted by computational studies. Surprisingly, the dose response curve was not sigmoidal, but exhibited a peak at 1.5 CNP:vWF proteins, which was not predicted by the model. This study describes a new antithrombotic agent that may have a different mechanism of action than current pharmaceutical therapies.

14.
J Biomech Eng ; 140(6)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29715334

RESUMO

Cytoplasmic viscosity-dependent margination of red blood cells (RBC) for flow inside microchannels was studied using numerical simulations, and the results were verified with microfluidic experiments. Wide range of suspension volume fractions or hematocrits was considered in this study. Lattice Boltzmann method for fluid-phase coupled with spectrin-link method for RBC membrane deformation was used for accurate analysis of cell margination. RBC margination behavior shows strong dependence on the internal viscosity of the RBCs. At equilibrium, RBCs with higher internal viscosity marginate closer to the channel wall and the RBCs with normal internal viscosity migrate to the central core of the channel. Same margination pattern has been verified through experiments conducted with straight channel microfluidic devices. Segregation between RBCs of different internal viscosity is enhanced as the shear rate and the hematocrit increases. Stronger separation between normal RBCs and RBCs with high internal viscosity is obtained as the width of a high aspect ratio channel is reduced. Overall, the margination behavior of RBCs with different internal viscosities resembles with the margination behavior of RBCs with different levels of deformability. Observations from this work will be useful in designing microfluidic devices for separating the subpopulations of RBCs with different levels of deformability that appear in many hematologic diseases such as sickle cell disease (SCD), malaria, or cancer.


Assuntos
Deformação Eritrocítica , Eritrócitos/citologia , Dispositivos Lab-On-A-Chip , Viscosidade , Hematócrito
15.
Am J Manag Care ; 24(1): 43-48, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29350505

RESUMO

OBJECTIVES: Some patients lack regular computer access and experience a digital divide that causes them to miss internet-based health innovations. The diffusion of smartphones has increased internet access across the socioeconomic spectrum, and increasing the channels through which patients can access their personal health records (PHRs) could help bridge the divide in PHR use. We examined PHR use through a computer-based Web browser or mobile device. STUDY DESIGN: Cross-sectional historical cohort analysis. METHODS: Among adult patients in the diabetes registry of an integrated healthcare delivery system, we studied the devices used to access their PHR during 2016. RESULTS: Among 267,208 patients with diabetes, 68.1% used the PHR in 2016; 60.6% of all log-ins were via computer and 39.4% were via mobile device. Overall, 63.9% used it from both a computer and mobile device, 29.6% used only a computer, and 6.5% used only a mobile device. After adjustment, patients who were black, Hispanic, or Asian; lived in lower socioeconomic status (SES) neighborhoods; or had lower engagement were all significantly more likely to use the PHR only from a mobile device (P <.05). Patients using the PHR only via mobile device used it less frequently. CONCLUSIONS: Mobile-ready PHRs may increase access among patients facing a digital divide in computer use, disproportionately reaching racial/ethnic minorities and lower SES patients. Nonetheless, even with a mobile-optimized and app-accessible PHR, differences in PHR use by race/ethnicity and SES remain. Continued efforts are needed to increase equitable access to PHRs among patients with chronic conditions.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Registros de Saúde Pessoal , Armazenamento e Recuperação da Informação/métodos , Armazenamento e Recuperação da Informação/estatística & dados numéricos , Internet/estatística & dados numéricos , Aplicativos Móveis/estatística & dados numéricos , Smartphone/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/estatística & dados numéricos , População Negra/estatística & dados numéricos , Doença Crônica , Estudos de Coortes , Estudos Transversais , Diabetes Mellitus , Etnicidade/estatística & dados numéricos , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos
16.
Health Aff (Millwood) ; 37(12): 1997-2004, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30633669

RESUMO

We took advantage of a change in protocol in an integrated delivery system's telephone consultation service-routing callers complaining of chest pain to physicians instead of registered nurses, whenever feasible-to explore whether tele-triage outcomes differed by staffing type. Comparing outcomes of 11,315 physician-directed calls to those of an equal number of nurse-directed calls in 2013, we found that the physician-directed calls were briefer (eight minutes versus thirteen minutes), produced fewer ED referrals (10 percent versus 16 percent), and resulted in higher patient adherence to the providers' site-of-care recommendation (86 percent versus 82 percent). Mortality rates at seven days were low for both physician- and nurse-directed calls (0.1 percent). We suspect that providers' immediate access to callers' comprehensive electronic health records and patients' rapid access to outpatient care likely contributed to the program's success. Our findings suggest that tele-triage can be used to safely and effectively manage an emergent complaint, and that physicians' expertise may bring additional efficiency to the process.


Assuntos
Dor no Peito/diagnóstico , Enfermeiras e Enfermeiros/estatística & dados numéricos , Médicos/estatística & dados numéricos , Consulta Remota/métodos , Triagem/métodos , Adulto , Idoso , Dor no Peito/etiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente
17.
Redox Rep ; 23(1): 1-24, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28514939

RESUMO

OBJECTIVES: This is a narrative review, investigating the antioxidant properties of drugs used in the management of diabetes, and discusses whether these antioxidant effects contribute to, confound, or conceal the effects of antioxidant therapy. METHODS: A systematic search for articles reporting trials, or observational studies on the antioxidant effect of drugs used in the treatment of diabetes in humans or animals was performed using Web of Science, PubMed, and Ovid. Data were extracted, including data on a number of subjects, type of treatment (and duration) received, and primary and secondary outcomes. The primary outcomes were reporting on changes in biomarkers of antioxidants concentrations and secondary outcomes were reporting on changes in biomarkers of oxidative stress. RESULTS: Diabetes Mellitus is a disease characterized by increased oxidative stress. It is often accompanied by a spectrum of other metabolic disturbances, including elevated plasma lipids, elevated uric acid, hypertension, endothelial dysfunction, and central obesity. This review shows evidence that some of the drugs in diabetes management have both in vivo and in vitro antioxidant properties through mechanisms such as scavenging free radicals and upregulating antioxidant gene expression. CONCLUSION: Pharmaceutical agents used in the treatment of type 2 diabetes has been shown to exert an antioxidant effect..


Assuntos
Antioxidantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Ácido Ascórbico/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Estresse Oxidativo/efeitos dos fármacos , Vitamina E/metabolismo
18.
Stroke Vasc Neurol ; 2(1): 21-29, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28959487

RESUMO

Intracerebral haemorrhage (ICH) is the most devastating and disabling type of stroke. Uncontrolled hypertension (HTN) is the most common cause of spontaneous ICH. Recent advances in neuroimaging, organised stroke care, dedicated Neuro-ICUs, medical and surgical management have improved the management of ICH. Early airway protection, control of malignant HTN, urgent reversal of coagulopathy and surgical intervention may increase the chance of survival for patients with severe ICH. Intensive lowering of systolic blood pressure to <140 mm Hg is proven safe by two recent randomised trials. Transfusion of platelets in patients on antiplatelet therapy is not indicated unless the patient is scheduled for surgical evacuation of haematoma. In patients with small haematoma without significant mass effect, there is no indication for routine use of mannitol or hypertonic saline (HTS). However, for patients with large ICH (volume > 30 cbic centmetre) or symptomatic perihaematoma oedema, it may be beneficial to keep serum sodium level at 140-150 mEq/L for 7-10 days to minimise oedema expansion and mass effect. Mannitol and HTS can be used emergently for worsening cerebral oedema, elevated intracranial pressure (ICP) or pending herniation. HTS should be administered via central line as continuous infusion (3%) or bolus (23.4%). Ventriculostomy is indicated for patients with severe intraventricular haemorrhage, hydrocephalus or elevated ICP. Patients with large cerebellar or temporal ICH may benefit from emergent haematoma evacuation. It is important to start intermittent pneumatic compression devices at the time of admission and subcutaneous unfractionated heparin in stable patients within 48 hours of admission for prophylaxis of venous thromboembolism. There is no benefit for seizure prophylaxis or aggressive management of fever or hyperglycaemia. Early aggressive comprehensive care may improve survival and functional recovery.


Assuntos
Anti-Hipertensivos/uso terapêutico , Fibrinolíticos/uso terapêutico , Hidratação , Acidente Vascular Cerebral Hemorrágico/terapia , Hemorragia Intracraniana Hipertensiva/terapia , Procedimentos Neurocirúrgicos , Transfusão de Plaquetas , Anti-Hipertensivos/efeitos adversos , Coagulação Sanguínea/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Tomada de Decisão Clínica , Terapia Combinada , Diagnóstico Precoce , Hidratação/efeitos adversos , Hidratação/mortalidade , Acidente Vascular Cerebral Hemorrágico/diagnóstico por imagem , Acidente Vascular Cerebral Hemorrágico/mortalidade , Acidente Vascular Cerebral Hemorrágico/fisiopatologia , Humanos , Hemorragia Intracraniana Hipertensiva/diagnóstico por imagem , Hemorragia Intracraniana Hipertensiva/mortalidade , Hemorragia Intracraniana Hipertensiva/fisiopatologia , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/mortalidade , Transfusão de Plaquetas/efeitos adversos , Transfusão de Plaquetas/mortalidade , Fatores de Risco , Resultado do Tratamento
19.
Psychophysiology ; 54(10): 1436-1443, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28593652

RESUMO

Pupillometry is commonly used in research to determine how much mental effort an individual is exerting while completing tasks. Traditionally, larger pupils are associated with increased mental effort when completing more difficult tasks. However, little research has investigated how pupils change as individuals learn a new task. In theory, as one repeatedly completes a task, the task demands should reduce, reliance on working memory should decrease, and the task should become more automatic. This should translate to faster completion times and smaller peak pupil dilations. We tested this hypothesis by having participants complete multiple trials of a cognitive task that requires individuals to orient themselves in space relative to a target. We found that trial completion times and maximum pupil size significantly reduced across trials. These data suggest that measuring changes in pupil dilation may help researchers determine whether individuals have shifted from a learned procedure to an automatic processing of information when learning a new task.


Assuntos
Aprendizagem/fisiologia , Pupila/fisiologia , Adulto , Medições dos Movimentos Oculares , Feminino , Humanos , Masculino , Adulto Jovem
20.
Front Neurol ; 8: 184, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28515710

RESUMO

BACKGROUND: Hypertension (HTN) is the most common cause of spontaneous intracerebral hemorrhage (ICH). The aim of this study is to investigate the role of resistant HTN in patients with ICH. METHODS AND RESULTS: We conducted a retrospective study of all consecutive ICH admissions at our medical center from November 2013 to October 2015. The clinical features of patients with resistant HTN (requiring four or more antihypertensive agents to keep systolic blood pressure <140 mm Hg) were compared with those with responsive HTN (requiring three or fewer agents). Of the 152 patients with hypertensive ICH, 48 (31.6%) had resistant HTN. Resistant HTN was independently associated with higher body mass index and proteinuria. Compared to the responsive group, patients with resistant HTN had higher initial blood pressures and greater requirement for ventilator support, hematoma evacuation, hypertonic saline therapy, and nicardipine infusion. Resistant HTN increases length of stay (LOS) in the intensive care unit (ICU) (4.2 vs 2.1 days; p = 0.007) and in the hospital (11.5 vs 7.0 days; p = 0.003). Multivariate regression analysis showed that the rate of systolic blood pressure >140 mm Hg and duration of nicardipine infusion were independently associated with LOS in the ICU. There was no significant difference in hematoma expansion and functional outcome at hospital discharge between the two groups. CONCLUSION: Resistant HTN in patients with ICH is associated with more medical interventions and longer LOS without effecting outcome at hospital discharge.

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