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1.
Artigo em Inglês | MEDLINE | ID: mdl-38753411

RESUMO

When learning a novel visuomotor mapping (e.g., mirror writing), accuracy can improve quickly through explicit, knowledge-based learning (e.g., aim left to go right), but after practice, implicit or procedural learning takes over, producing fast, natural movements. This procedural learning occurs automatically, whereas it has recently been found that knowledge-based learning can be suppressed by the gradual introduction of the novel mapping when participants must make fast movements and visuomotor perturbations are small (e.g., 30° rotations). We explored the range of task instructions, perturbation parameters, and feedback that preclude or encourage this suppression. Using a reaching task with a rotation between screen position and movement direction, we found that knowledge-based learning could be suppressed even for an extreme 90° rotation, but only if it was introduced gradually and only under instructions to move quickly. If the rotation was introduced abruptly or if instructions emphasized accuracy over speed, knowledge-based learning occurred. A second experiment indicated that knowledge-based learning always occurred in the absence of continuous motion feedback, evidenced by the time course of learning, the aftereffects of learning when the rotation was abruptly removed, and the outcome of formal model comparison between a dual-state (procedural and knowledge-based) versus a single-state (procedural only) learning model of the data. A third experiment replicated the findings and verified that the knowledge-based component of the dual-state model corresponded to explicit aiming, whereas the procedural component was slow to unlearn. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

2.
Heliyon ; 9(4): e14909, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37064446

RESUMO

Background: Pulse pressure intensity in middle-aged adults is a risk factor for dementia. The Guardian device (The Brain Protection Company, Sydney, Australia) has been developed to reduce pulse pressure, as a potential therapy. Objectives: The aim of this study was to evaluate the safety of the Guardian, a novel pulse modulation device designed to reduce the intensity of the pulse pressure that penetrates into the cerebral small vessels. The Guardian is a helix that gently wraps around the common carotid artery (CCA) to slightly change its shape, to absorb pulsatility, without lowering flow. Methods: The Guardian was implanted bilaterally on the CCAs of 10 mature sheep for chronic implant periods of 3, 6 or 8 months. The ratio of internal device diameter to outer diameter of the CCA varied from 63% to 92% (n = 20). The implant position on the vessel was marked surgically at implant. Gross pathology and histopathology of the CCA were examined at 3- and 6-months post explant. Most devices were explanted using open surgery, however minimally invasive surgical explant techniques were examined in 2 animals to assess the potential of this approach for explant in humans if required. Results: The Guardian was successfully implanted with no adverse events, and minimally invasive explant appeared to be viable for removal. Following implant, the device was surrounded by a thin fibrous capsule, with similar pathology at 3- and 6-months. Minimal or no movement was observed. CCA sections appeared histologically normal, with no evidence of thrombosis, stenosis, fibrosis, chronic inflammatory response, or vessel degeneration. Conclusions: The feasibility of surgical implantation and biomaterial safety of the Guardian was confirmed over 8 months. Minimally invasive explant of the Guardian has the potential to be viable. Further work is required to demonstrate efficacy in vitro and/or in vivo before evaluation in humans.

3.
J Diabetes Sci Technol ; : 19322968221123083, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36112811

RESUMO

BACKGROUND: Many type 1 diabetes patients using continuous subcutaneous insulin infusion (CSII) suffer from the phenomenon of unexplained hypoglycemia or "site loss." Site loss is hypothesized to be caused by toxic excipients, for example, phenolic compounds within insulin formulations that are used as preservatives and stabilizers. Here, we develop a bioinspired polyelectrolyte-modified carbon electrode for effective electrooxidative removal of phenol from insulin and eventual incorporations into an infusion set of a CSII device. METHODS: We modified a carbon screen printed electrode (SPE) with poly-L-lysine (PLL) to avoid passivation due to polyphenol deposition while still removing phenolic compounds from insulin injections. We characterized these electrodes using scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) and compared their data with data from bare SPEs. Furthermore, we performed electrochemical measurements to determine the extent of passivation, and high-performance liquid chromatography (HPLC) measurements to confirm both the removal of phenol and the integrity of insulin after phenol removal. RESULTS: Voltammetry measurements show that electrode passivation due to polyphenol deposition is reduced by a factor of 2X. HPLC measurements confirm a 10x greater removal of phenol by our modified electrodes relative to bare electrodes. CONCLUSION: Using bioinspired polyelectrolytes to modify a carbon electrode surface aids in the electrooxidation of phenolic compounds from insulin and is a step toward integration within an infusion set for mitigating site loss.

4.
Clin Imaging ; 89: 37-42, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35696946

RESUMO

The carnage wrought by systemic racism through social, judicial, and health injustices compels us to work towards a system that is fair and just for patients and colleagues. The evidence that change is necessary in medicine is hiding in plain sight in literature, oral histories, medical records, and news media. Notwithstanding this evidence, changing a system 400 years in the making will require a major paradigm shift. One of the many ways our department sought to catalyze such a shift was through media consumption, reflection, and discussion. Reading and studying literature and humanities in medicine can awaken our consciousness by making medicine an embodied practice that considers the totality of patients' lives in ways that a disembodied, purely scientific approach cannot. Thus, we started a Racial and Social Justice Book Club to normalize discussions about racial and social (in)justice and examine everything through an anti-racist lens. Herein, we describe our experiences in the inaugural year of the Book Club, a space to lend credence and dignity to the voices, experiences, and stories of folks who have long been marginalized by power structures in America, including medicine.


Assuntos
Educação Médica , Justiça Social , Humanos
5.
J Pers Med ; 11(12)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34945849

RESUMO

The study aims to create a preoperative model from baseline demographic and health-related quality of life scores (HRQOL) to predict a good to excellent early clinical outcome using a machine learning (ML) approach. A single spine surgery center retrospective review of prospectively collected data from January 2016 to December 2020 from the institutional registry (SpineREG) was performed. The inclusion criteria were age ≥ 18 years, both sexes, lumbar arthrodesis procedure, a complete follow up assessment (Oswestry Disability Index-ODI, SF-36 and COMI back) and the capability to read and understand the Italian language. A delta of improvement of the ODI higher than 12.7/100 was considered a "good early outcome". A combined target model of ODI (Δ ≥ 12.7/100), SF-36 PCS (Δ ≥ 6/100) and COMI back (Δ ≥ 2.2/10) was considered an "excellent early outcome". The performance of the ML models was evaluated in terms of sensitivity, i.e., True Positive Rate (TPR), specificity, i.e., True Negative Rate (TNR), accuracy and area under the receiver operating characteristic curve (AUC ROC). A total of 1243 patients were included in this study. The model for predicting ODI at 6 months' follow up showed a good balance between sensitivity (74.3%) and specificity (79.4%), while providing a good accuracy (75.8%) with ROC AUC = 0.842. The combined target model showed a sensitivity of 74.2% and specificity of 71.8%, with an accuracy of 72.8%, and an ROC AUC = 0.808. The results of our study suggest that a machine learning approach showed high performance in predicting early good to excellent clinical results.

6.
BMC Palliat Care ; 19(1): 160, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33059636

RESUMO

BACKGROUND: Most terminally ill cancer patients prefer to die at home, but a majority die in institutional settings. Research questions about this discrepancy have not been fully answered. This study applies artificial intelligence and machine learning techniques to explore the complex network of factors and the cause-effect relationships affecting the place of death, with the ultimate aim of developing policies favouring home-based end-of-life care. METHODS: A data mining algorithm and a causal probabilistic model for data analysis were developed with information derived from expert knowledge that was merged with data from 116 deceased cancer patients in southern Switzerland. This data set was obtained via a retrospective clinical chart review. RESULTS: Dependencies of disease and treatment-related decisions demonstrate an influence on the place of death of 13%. Anticancer treatment in advanced disease prevents or delays communication about the end of life between oncologists, patients and families. Unknown preferences for the place of death represent a great barrier to a home death. A further barrier is the limited availability of family caregivers for terminal home care. The family's preference for the last place of care has a high impact on the place of death of 51%, while the influence of the patient's preference is low, at 14%. Approximately one-third of family systems can be empowered by health care professionals to provide home care through open end-of-life communication and good symptom management. Such intervention has an influence on the place of death of 17%. If families express a convincing preference for home care, the involvement of a specialist palliative home care service can increase the probability of home deaths by 24%. CONCLUSION: Concerning death at home, open communication about death and dying is essential. Furthermore, for the patient preference for home care to be respected, the family's decision for the last place of care seems to be key. The early initiation of family-centred palliative care and the provision of specialist palliative home care for patients who wish to die at home are suggested.


Assuntos
Atitude Frente a Morte , Neoplasias/mortalidade , Neoplasias/psicologia , Assistência Terminal/métodos , Assistência Terminal/psicologia , Doente Terminal/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Inteligência Artificial , Interpretação Estatística de Dados , Mineração de Dados , Feminino , Serviços de Assistência Domiciliar , Hospitalização , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Satisfação do Paciente , Probabilidade , Suíça/epidemiologia , Adulto Jovem
7.
Phlebology ; 35(8): 550-555, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32639862

RESUMO

The coronavirus disease 2019 (COVID-19) global pandemic has resulted in diversion of healthcare resources to the management of patients infected with SARS-CoV-2 virus. Elective interventions and surgical procedures in most countries have been postponed and operating room resources have been diverted to manage the pandemic. The Venous and Lymphatic Triage and Acuity Scale was developed to provide an international standard to rationalise and harmonise the management of patients with venous and lymphatic disorders or vascular anomalies. Triage urgency was determined based on clinical assessment of urgency with which a patient would require medical treatment or surgical intervention. Clinical conditions were classified into six categories of: (1) venous thromboembolism (VTE), (2) chronic venous disease, (3) vascular anomalies, (4) venous trauma, (5) venous compression and (6) lymphatic disease. Triage urgency was categorised into four groups and individual conditions were allocated to each class of triage. These included (1) medical emergencies (requiring immediate attendance), example massive pulmonary embolism; (2) urgent (to be seen as soon as possible), example deep vein thrombosis; (3) semi-urgent (to be attended to within 30-90 days), example highly symptomatic chronic venous disease, and (4) discretionary/non-urgent- (to be seen within 6-12 months), example chronic lymphoedema. Venous and Lymphatic Triage and Acuity Scale aims to standardise the triage of patients with venous and lymphatic disease or vascular anomalies by providing an international consensus-based classification of clinical categories and triage urgency. The scale may be used during pandemics such as the current COVID-19 crisis but may also be used as a general framework to classify urgency of the listed conditions.


Assuntos
Infecções por Coronavirus/terapia , Sistemas de Apoio a Decisões Clínicas/normas , Técnicas de Apoio para a Decisão , Serviço Hospitalar de Emergência/normas , Doenças Linfáticas/terapia , Pneumonia Viral/terapia , Triagem/normas , Doenças Vasculares/terapia , COVID-19 , Tomada de Decisão Clínica , Consenso , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Necessidades e Demandas de Serviços de Saúde/normas , Humanos , Doenças Linfáticas/diagnóstico , Doenças Linfáticas/epidemiologia , Pandemias , Seleção de Pacientes , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Doenças Vasculares/diagnóstico , Doenças Vasculares/epidemiologia
8.
J Vasc Surg Venous Lymphat Disord ; 8(5): 706-710, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32426220

RESUMO

The coronavirus disease 2019 (COVID-19) global pandemic has resulted in diversion of healthcare resources to the management of patients infected with SARS-CoV-2 virus. Elective interventions and surgical procedures in most countries have been postponed and operating room resources have been diverted to manage the pandemic. The Venous and Lymphatic Triage and Acuity Scale was developed to provide an international standard to rationalise and harmonise the management of patients with venous and lymphatic disorders or vascular anomalies. Triage urgency was determined based on clinical assessment of urgency with which a patient would require medical treatment or surgical intervention. Clinical conditions were classified into six categories of: (1) venous thromboembolism (VTE), (2) chronic venous disease, (3) vascular anomalies, (4) venous trauma, (5) venous compression and (6) lymphatic disease. Triage urgency was categorised into four groups and individual conditions were allocated to each class of triage. These included (1) medical emergencies (requiring immediate attendance), example massive pulmonary embolism; (2) urgent (to be seen as soon as possible), example deep vein thrombosis; (3) semiurgent (to be attended to within 30-90 days), example highly symptomatic chronic venous disease, and (4) discretionary/nonurgent- (to be seen within 6-12 months), example chronic lymphoedema. Venous and Lymphatic Triage and Acuity Scale aims to standardise the triage of patients with venous and lymphatic disease or vascular anomalies by providing an international consensus-based classification of clinical categories and triage urgency. The scale may be used during pandemics such as the current COVID-19 crisis but may also be used as a general framework to classify urgency of the listed conditions.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Doenças Linfáticas/terapia , Pneumonia Viral/epidemiologia , Triagem/organização & administração , Doenças Vasculares/terapia , Veias , COVID-19 , Consenso , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/prevenção & controle , Humanos , Cooperação Internacional , Doenças Linfáticas/diagnóstico , Pandemias/prevenção & controle , Seleção de Pacientes , Pneumonia Viral/diagnóstico , Pneumonia Viral/prevenção & controle , Reprodutibilidade dos Testes , SARS-CoV-2 , Índice de Gravidade de Doença , Sociedades Médicas , Doenças Vasculares/diagnóstico , Procedimentos Cirúrgicos Vasculares
9.
Bioresour Technol ; 224: 373-379, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27864134

RESUMO

The objective of this work was to evaluate the technical feasibility of using both oil-extracted microalgae (M) and glycerol (G) in co-digestion with chicken litter (CL), thereby improving biochemical methane potential (BMP). Different feedstock ratios of M (0-30%), G (0-3%) and CL (67-100%) were investigated to determine the best co-digestion condition under mesophilic conditions. According to the modified Gompertz model, the best BMP (131.1mLCH4gVSfed-1) was obtained with the triple co-digestion (M:G:CL) in a proportion of 30:3:67. This yielded a methane production rate (µm) of 3.3mLCH4gVSfed-1d-1 and a lag time (λ) of 17.4d. This treatment reduced chemical oxygen demand (COD) by 91.02% and increased the methane yield 15.8% with respect to the CL control.


Assuntos
Glicerol/metabolismo , Metano/biossíntese , Microalgas/metabolismo , Óleos/isolamento & purificação , Eliminação de Resíduos/métodos , Resíduos , Acetatos/metabolismo , Anaerobiose , Animais , Biocombustíveis/análise , Ácido Butírico/metabolismo , Galinhas , Ácidos Graxos Voláteis/análise , Concentração de Íons de Hidrogênio , Modelos Teóricos , Análise de Componente Principal , Propionatos/farmacologia
10.
ANZ J Surg ; 81(11): 822-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22295418

RESUMO

INTRODUCTION: The endovascular repair of bilateral iliac aneurysms using bilateral Iliac Branch Devices (IBDs) has been infrequently performed and reported.We aim to describe this technique and report on the results of our case series. METHODS: Three different device designs are available. The procedural options include a totally transfemoral approach, or a combined transfemoral and brachial approach. Clinical records for patients who have had this procedure were reviewed. RESULTS: The indications for the technique include bilateral common iliac artery aneurysm repair, with or without concomitant abdominal aortic aneurysm repair. Considerations include the timing of main body endovascular aortic aneurysm repair (EVAR) device introduction, the use of a proximal access site and the type of IIA stent-graft that is used. Between 2007 and 2010, six patients had bilateral IBD implantation. All patients required an EVAR main body device in addition to bilateral IBDs. Eighty-three per cent were males, mean age was 73 years. Mean follow up was 15 months. Technical success was obtained in 100% of cases. There was one branch occlusion (8.3%). There were no type I endoleaks. One patient had a type II endoleak. CONCLUSIONS: Bilateral IBDs can be used safely and with excellent rates of technical success and branch patency in appropriately selected patients.


Assuntos
Implante de Prótese Vascular/métodos , Prótese Vascular , Aneurisma Ilíaco/cirurgia , Idoso , Idoso de 80 Anos ou mais , Implante de Prótese Vascular/efeitos adversos , Estudos de Coortes , Feminino , Seguimentos , Humanos , Aneurisma Ilíaco/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Radiografia , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
11.
Proc Natl Acad Sci U S A ; 106(10): 3970-5, 2009 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-19234122

RESUMO

The enumeration of rare circulating epithelial cells (CEpCs) in the peripheral blood of metastatic cancer patients has shown promise for improved cancer prognosis. Moving beyond enumeration, molecular analysis of CEpCs may provide candidate surrogate endpoints to diagnose, treat, and monitor malignancy directly from the blood samples. Thorough molecular analysis of CEpCs requires the development of new sample preparation methods that yield easily accessible and purified CEpCs for downstream biochemical assays. Here, we describe a new immunomagnetic cell separator, the MagSweeper, which gently enriches target cells and eliminates cells that are not bound to magnetic particles. The isolated cells are easily accessible and can be extracted individually based on their physical characteristics to deplete any cells nonspecifically bound to beads. We have shown that our device can process 9 mL of blood per hour and captures >50% of CEpCs as measured in spiking experiments. We have shown that the separation process does not perturb the gene expression of rare cells. To determine the efficiency of our platform in isolating CEpCs from patients, we have isolated CEpCs from all 47 tubes of 9-mL blood samples collected from 17 women with metastatic breast cancer. In contrast, we could not find any circulating epithelial cells in samples from 5 healthy donors. The isolated CEpCs are all stored individually for further molecular analysis.


Assuntos
Células Sanguíneas/citologia , Separação Celular/instrumentação , Células Epiteliais/citologia , Magnetismo/instrumentação , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Simulação por Computador , Feminino , Regulação da Expressão Gênica , Antígeno HLA-A2/imunologia , Humanos , Modelos Imunológicos
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