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1.
Crit Care Med ; 50(4): 624-632, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34582412

RESUMO

OBJECTIVES: Coronavirus disease 2019 has been reported to be a prothrombotic condition; however, multicenter data comparing this with other viral pneumonias in those requiring extracorporeal membrane oxygenation are lacking. We conducted a multicenter study using whole-body CT to examine the prevalence, severity, and nature of vascular complications in coronavirus disease 2019 in comparison with patients with other viral pneumonias. DESIGN: We analyzed whole-body CT scans for the presence of vascular thrombosis (defined as pulmonary artery thrombus, venous thrombus, systemic arterial thrombus, or end-organ infarct). The severity, distribution, and morphology of pulmonary artery thrombus were characterized. Competing risk cumulative incidence analysis was used to compare survival with discharge. SETTING: Three centers of the English national extracorporeal membrane oxygenation service. PATIENTS: Consecutive patients admitted with either coronavirus disease 2019 or noncoronavirus disease 2019 viral pneumonia admitted from January 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: One-hundred thirty-six patients (45.2 ± 10.6 yr old, 39/146 [27%] female) requiring extracorporeal membrane oxygenation support underwent whole-body CT scans at admission. Of these, 86 had coronavirus disease 2019 pneumonia, and 50 had noncoronavirus disease 2019 viral pneumonia. Vascular thrombosis was seen more often in patients with coronavirus disease 2019 (odds ratio, 12.9 [95% CI 4.5-36.8]). In those with coronavirus disease 2019, 57 (73%) demonstrated pulmonary artery thrombus or pulmonary perfusion defects. Eighty-two percent of thrombus exhibited emboli-like morphology. The location of pulmonary artery thrombus and parenchymal perfusion defects was only concordant in 30% of cases. The risk of mortality was higher in those with coronavirus disease 2019 compared with noncoronavirus disease 2019 pneumonia (χ2 = 3.94; p = 0.047). Mortality was no different in coronavirus disease 2019 patients with or without vascular thrombosis (χ2 = 0.44; p = 0.51). CONCLUSIONS: In patients who received extracorporeal membrane oxygenation, coronavirus disease 2019 is associated with a higher prevalence of vascular thrombosis compared with noncoronavirus disease viral pneumonias. The pattern of pulmonary vascular changes suggests concurrent embolic disease and small vessel disease. Despite this, vascular thrombosis was not linked to poorer short-term prognosis in those with coronavirus disease 2019.


Assuntos
COVID-19/complicações , Oxigenação por Membrana Extracorpórea , Pneumonia Viral/complicações , Trombose/etiologia , Adulto , COVID-19/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/terapia , Prognóstico , Trombose/diagnóstico por imagem , Tomografia Computadorizada por Raios X
2.
Am J Physiol Gastrointest Liver Physiol ; 316(5): G585-G597, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30817180

RESUMO

We investigated the migration of intestinal immune cells to the liver and their contribution to alcoholic liver disease. In mice fed ethanol, we found that an increased number of invariant natural killer T (iNKT) cells, which respond to the antigen presented by CD1d, migrated from mesenteric lymph nodes to the liver. iNKT cells react to lipid antigens, so we studied their activities in mice with intestinal epithelial cell-specific deletion of Pparg (PpargΔIEC) as a model for altering intestinal lipidomic profiles. Levels of CD1d increased in intestines of ethanol-fed PpargΔIEC mice, and in cell-tracking experiments, more iNKT cells migrated to the liver, compared with mice without disruption of Pparg. Livers of PpargΔIEC mice had increased markers of apoptosis and liver injury after ethanol feeding. iNKT cells isolated from livers of ethanol-fed PpargΔIEC mice induced apoptosis of cultured hepatocytes. An inhibitor of iNKT cells reduced ethanol-induced liver injury in PpargΔIEC mice. Duodenal tissues from patients with alcohol-use disorder have been found to have increased levels of CD1d compared with tissues from patients without alcohol overuse. Ethanol use, therefore, activates iNKT cells in the intestine to migrate to liver, where they-along with the resident hepatic iNKT cells-contribute to hepatocyte death and injury. NEW & NOTEWORTHY In this article, we studied migration of intestinal immune cells into the liver in response to ethanol-induced liver disease. We found that chronic ethanol feeding induces expression of CD1d by enterocytes, which activate invariant natural killer T (iNKT) cells in mesenteric lymph nodes; activation is further increased with loss of peroxisome proliferator-activated receptor gamma gene and altered lipid profiles. The activated iNKT cells migrate into the liver, where they promote hepatocyte apoptosis. Patients with alcohol use disorder have increased expression of CD1d in the small intestine. Strategies to block these processes might be developed to treat alcoholic liver disease.


Assuntos
Enterócitos , Etanol/farmacologia , Hepatócitos , Hepatopatias Alcoólicas , Células T Matadoras Naturais , Animais , Antígenos CD1d/metabolismo , Apoptose , Ensaios de Migração de Leucócitos/métodos , Movimento Celular , Depressores do Sistema Nervoso Central/farmacologia , Enterócitos/efeitos dos fármacos , Enterócitos/imunologia , Enterócitos/metabolismo , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepatopatias Alcoólicas/metabolismo , Hepatopatias Alcoólicas/patologia , Ativação Linfocitária , Camundongos , Células T Matadoras Naturais/efeitos dos fármacos , Células T Matadoras Naturais/metabolismo
3.
J Magn Reson Imaging ; 49(7): e176-e182, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30637879

RESUMO

BACKGROUND: Since 2008 primary care physicians (GPs) in our region have been allowed open access to knee MRI scans. There are questions about whether this changes referral practice and if it is an effective use of resources. PURPOSE: To describe the change in demographics of patients referred for knee MRI following implementation of a new referral pathway. STUDY TYPE: Retrospective observational study. POPULATION: All primary care referrals between 2008 and 2015 for knee MRI from a population of 900,000. FIELD STRENGTH/SEQUENCE: Not applicable. ASSESSMENT: Demographic profile and number of knee MRI referrals and subsequent arthroscopies. STATISTICAL TESTS: Comparisons between urban and rural populations used the t-test. Test for normality used Shapiro-Wilks. Comparison between abnormal MRI proportions used a chi-squared test. RESULTS: There were 23,928 knee MRI referrals (10,695 from GPs) between 2000 and 2015. MRI knee referrals rose from 210 in 2008 to 2379 in 2015. The average age of the patient decreased from 46.8 (SD = 14.9) in 2008 to 41.3 (SD = 14.7) in 2015. Conversion to arthroscopy declined from 15.4% to 10.2%, but there was no significant change in abnormal scan proportion. Conversion rates showed no significant difference between rural (9.6%) and urban populations (10.5%). Referral rates were significantly higher in low socioeconomic status areas (47.3% vs. 34.6%). The median referral rate per 1000 patients was 13.8 (interquartile range = 8.4). Referral rates varied widely between practices. DATA CONCLUSION: Despite a large rise in knee MRI referrals from primary care, there has been no substantial change in the age profile, suggesting that there has been no increase in inappropriate referral of elderly patients in whom MRI is unlikely to influence management. A modest decrease in the conversion rate to arthroscopy may be reasonably offset against a decrease in secondary care referrals. Socioeconomic status of the target population must be considered when planning primary care knee MRI services. LEVEL OF EVIDENCE: 4 Technical Efficacy Stage: 6 J. Magn. Reson. Imaging 2019.


Assuntos
Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética , Atenção Primária à Saúde/organização & administração , Encaminhamento e Consulta , Adulto , Idoso , Artroscopia , Feminino , Clínicos Gerais , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Alocação de Recursos , Estudos Retrospectivos , Classe Social , Reino Unido
4.
J Exp Biol ; 222(Pt 5)2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30850509

RESUMO

The evolutionary conservation of neural mechanisms for forming and maintaining pair bonds is unclear. Oxytocin, vasopressin and dopamine (DA) transmitter systems have been shown to be important in pair-bond formation and maintenance in several vertebrate species. We examined the role of dopamine in formation of song preference in zebra finches, a monogamous bird. Male courtship song is an honest signal of sexual fitness; thus, we measured female song preference to evaluate the role of DA in mate selection and pair-bond formation, using an operant conditioning paradigm. We found that DA acting through the D2 receptor, but not the D1 receptor, can induce a song preference in unpaired female finches and that blocking the D2 receptor abolished song preference in paired females. These results suggest that similar neural mechanisms for pair-bond formation are evolutionarily conserved in rodents and birds.


Assuntos
Proteínas Aviárias/genética , Corte , Dopamina/metabolismo , Receptores de Dopamina D1/genética , Receptores de Dopamina D2/genética , Aves Canoras/fisiologia , Vocalização Animal , Animais , Proteínas Aviárias/metabolismo , Condicionamento Operante , Feminino , Tentilhões/fisiologia , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo
5.
BMC Med Imaging ; 19(1): 14, 2019 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-30736759

RESUMO

BACKGROUND: The assessment of liver percentage fat fraction (%FF) using proton density fat fraction sequences is becoming increasingly accessible. Previous studies have tended to use multiple small ROIs that focus on Couinaud segments. In an effort to simplify day-to-day analysis, this study assesses the impact of using larger, elliptical ROIs focused on a single hepatic lobe. Additionally, we assess the impact of sampling fewer transhepatic slices when measuring %FF. METHODS: Retrospective analysis of prospectively obtained images from 34 volunteers using an IDEAL IQ sequence. Two observers independently measured %FF using three different protocols: freehand whole-liver ROI (fh-ROI), elliptical-ROI on the right lobe (rt-ROI) and elliptical-ROI on the left lobe (lt-ROI). RESULTS: Inter-observer reliability for all measurements techniques was 'excellent' (Spearman's rank correlation coefficients 0.81-0.98). There was a significant difference (Paired Wilcoxon Test: p < 0.001) between the median %FF obtained using fh-ROI when compared to the rt-ROI method, the maximum mean difference between the two techniques was 2.79% (95% CI). For all sampling methods a Kruskall-Wallis analysis demonstrated no significant difference in mean %FF when the number of slices sampled was reduced from 11 to 1. The mean coefficient of variance increased when more slices were sampled (3 slices = 0.1, 11 slices = 0.17, p < 0.001). CONCLUSION: Simplified ROIs focused on one hepatic lobe provide %FF measurements that are unlikely to be sufficiently accurate for use in clinical practice. Freehand whole-liver ROIs should be used in preference. A single freehand ROI measurement taken at the level of the hepatic hilum yields a %FF that is representative of the mean whole liver % FF. Multiple slices are needed to measure heterogeneity.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Feminino , Voluntários Saudáveis , Humanos , Masculino , Variações Dependentes do Observador , Estudos Retrospectivos
6.
NPJ Parkinsons Dis ; 10(1): 122, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918385

RESUMO

Quantification of motor symptom progression in Parkinson's disease (PD) patients is crucial for assessing disease progression and for optimizing therapeutic interventions, such as dopaminergic medications and deep brain stimulation. Cumulative and heuristic clinical experience has identified various clinical signs associated with PD severity, but these are neither objectively quantifiable nor robustly validated. Video-based objective symptom quantification enabled by machine learning (ML) introduces a potential solution. However, video-based diagnostic tools often have implementation challenges due to expensive and inaccessible technology, and typical "black-box" ML implementations are not tailored to be clinically interpretable. Here, we address these needs by releasing a comprehensive kinematic dataset and developing an interpretable video-based framework that predicts high versus low PD motor symptom severity according to MDS-UPDRS Part III metrics. This data driven approach validated and robustly quantified canonical movement features and identified new clinical insights, not previously appreciated as related to clinical severity, including pinkie finger movements and lower limb and axial features of gait. Our framework is enabled by retrospective, single-view, seconds-long videos recorded on consumer-grade devices such as smartphones, tablets, and digital cameras, thereby eliminating the requirement for specialized equipment. Following interpretable ML principles, our framework enforces robustness and interpretability by integrating (1) automatic, data-driven kinematic metric evaluation guided by pre-defined digital features of movement, (2) combination of bi-domain (body and hand) kinematic features, and (3) sparsity-inducing and stability-driven ML analysis with simple-to-interpret models. These elements ensure that the proposed framework quantifies clinically meaningful motor features useful for both ML predictions and clinical analysis.

7.
medRxiv ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38883720

RESUMO

Background: Neuropsychiatric symptoms are common and disabling in Parkinson's disease (PD), with troublesome anxiety occurring in one-third of patients. Management of anxiety in PD is challenging, hampered by insufficient insight into underlying mechanisms, lack of objective anxiety measurements, and largely ineffective treatments.In this study, we assessed the intracranial neurophysiological correlates of anxiety in PD patients treated with deep brain stimulation (DBS) in the laboratory and at home. We hypothesized that low-frequency (theta-alpha) activity would be associated with anxiety. Methods: We recorded local field potentials (LFP) from the subthalamic nucleus (STN) or the globus pallidus pars interna (GPi) DBS implants in three PD cohorts: 1) patients with recordings (STN) performed in hospital at rest via perioperatively externalized leads, without active stimulation, both ON or OFF dopaminergic medication; 2) patients with recordings (STN or GPi) performed at home while resting, via a chronically implanted commercially available sensing-enabled neurostimulator (Medtronic Percept™ device), ON dopaminergic medication, with stimulation both ON or OFF; 3) patients with recordings performed at home while engaging in a behavioral task via STN and GPi leads and electrocorticography paddles (ECoG) over premotor cortex connected to an investigational sensing-enabled neurostimulator, ON dopaminergic medication, with stimulation both ON or OFF.Trait anxiety was measured with validated clinical scales in all participants, and state anxiety was measured with momentary assessment scales at multiple time points in the two at-home cohorts. Power in theta (4-8 Hz) and alpha (8-12 Hz) ranges were extracted from the LFP recordings, and their relation with anxiety ratings was assessed using linear mixed-effects models. Results: In total, 33 PD patients (59 hemispheres) were included. Across three independent cohorts, with stimulation OFF, basal ganglia theta power was positively related to trait anxiety (all p<0.05). Also in a naturalistic setting, with individuals at home at rest with stimulation and medication ON, basal ganglia theta power was positively related to trait anxiety (p<0.05). This relationship held regardless of the hemisphere and DBS target. There was no correlation between trait anxiety and premotor cortical theta-alpha power. There was no within-patient association between basal ganglia theta-alpha power and state anxiety. Conclusion: We showed that basal ganglia theta activity indexes trait anxiety in PD. Our data suggest that theta could be a possible physiomarker of neuropsychiatric symptoms and specifically of anxiety in PD, potentially suitable for guiding advanced DBS treatment tailored to the individual patient's needs, including non-motor symptoms.

8.
Mater Horiz ; 10(9): 3393-3403, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37350303

RESUMO

Metal-assisted plasma etching (MAPE) of silicon (Si) is an etching technique driven by the catalytic activity of metals such as gold in fluorine-based plasma environments. In this work, the role of the Si substrate was investigated by examining the effects of the dopant concentration in both n- and p-type Si and the dopant atom type in n-type Si in SF6/O2 mixed gas plasma. At the highest dopant concentrations, both n- and p-type Si initially exhibit inhibition of the MAPE-enhanced etching. As the etch progresses, MAPE initiates, resulting in catalytic etching of the underlying Si at the metal-Si interface. Interestingly, MAPE-enhanced etching increases with decreasing doping concentrations for both n- and p-type Si substrates, distinct from results for the similar but divergent, metal-assisted chemical etching of silicon in liquid. Our findings show that the metal-Si interface remains essential to MAPE, and surface enrichment of the dopant atoms or other surface chemistries and the size of metal nanoparticles play roles in modulating catalytic activity.

9.
Clin Breast Cancer ; 22(1): e74-e79, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34690081

RESUMO

PURPOSE: The use of the 21-gene Recurrence Score (RS) assay is emerging in node-positive estrogen receptor (ER)+ HER2-negative breast cancer (BC), particularly as initial data from the RxPONDER trial are now available. We investigated the impact of the RS result on adjuvant treatment decisions in such patients. PATIENTS AND METHODS: This prospective, multi-center study enrolled patients with ER+, HER2-negative BC and 1 to 3 positive nodes (microscopic [N1mi] or macroscopic [N1]). Treating oncologists documented treatment recommendations/plan before and after knowing the RS result. Sample size was determined assuming an overall treatment change rate (from chemohormonal therapy [CHT] to hormone therapy [HT] and vice-versa) of ≥30%. RESULTS: The study included 84 patients across 5 regional cancer centers, of whom 82 underwent 21-gene testing (77%, N1 disease; 63% grade 2 tumors). Of the RS-tested patients, 60%, 33%, and 7% had RS 0 to 17, 18 to 30, and 31 to 100, respectively. In 43 patients (52%), treatment changed post-RS: 40 patients (49%) from CHT to HT and 3 patients (4%) from HT to CHT. The net change was a 45% reduction in chemotherapy use. Treatment recommendation changes were consistent with the RS result. In RS 0 to 17 patients, the only documented change was from CHT to HT (27 patients). In RS 18-30 patients, change was noted in both directions (CHT-to-HT, 13 patients; HT-to-CHT, 3 patients). No treatment change was reported for the RS 31 to 100 patients, all of whom were recommended CHT pre-testing. CONCLUSION: Our results support the clinical utility of the RS assay in ER+ HER2-negative BC with 1 to 3 positive nodes.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Recidiva Local de Neoplasia/prevenção & controle , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Adulto , Antineoplásicos/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Estudos Prospectivos
10.
Med Teach ; 33(10): e522-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21942488

RESUMO

BACKGROUND: A suite of 10 online virtual patients developed using the IVIMEDS 'Riverside' authoring tool has been introduced into our undergraduate general practice clerkship. These cases provide a multimedia-rich experience to students. Their interactive nature promotes the development of clinical reasoning skills such as discriminating key clinical features, integrating information from a variety of sources and forming diagnoses and management plans. AIMS: To evaluate the usefulness and usability of a set of online virtual patients in an undergraduate general practice clerkship. METHOD: Online questionnaire completed by students after their general practice placement incorporating the System Usability Scale questionnaire. RESULTS: There was a 57% response rate. Ninety-five per cent of students agreed that the online package was a useful learning tool and ranked virtual patients third out of six learning modalities. Questions and answers and the use of images and videos were all rated highly by students as useful learning methods. The package was perceived to have a high level of usability among respondents. CONCLUSION: Feedback from students suggest that this implementation of virtual patients, set in primary care, is user friendly and rated as a valuable adjunct to their learning. The cost of production of such learning resources demands close attention to design.


Assuntos
Simulação por Computador , Instrução por Computador/métodos , Cirurgia Geral/educação , Atenção Primária à Saúde/métodos , Interface Usuário-Computador , Adulto , Instrução por Computador/instrumentação , Educação de Graduação em Medicina/métodos , Avaliação Educacional/métodos , Feminino , Clínicos Gerais/educação , Cirurgia Geral/instrumentação , Cirurgia Geral/métodos , Humanos , Aprendizagem , Masculino , Estudantes de Medicina , Inquéritos e Questionários , Ensino/métodos , Reino Unido , Adulto Jovem
11.
Lupus Sci Med ; 8(1)2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34876504

RESUMO

OBJECTIVE: To investigate the occurrence of and risk factors for progression of carotid intima media thickness (IMT) and plaque in women with and without SLE. METHODS: A cohort of 149 women with SLE and 126 controls participated in SOLVABLE (Study of Lupus Vascular and Bone Long-term Endpoints). Demographics, cardiovascular and SLE factors, and laboratory assessments were collected at baseline. Carotid IMT and plaque were measured using B-mode ultrasound at baseline and at 5-year follow-up. Regression models were used to identify predictors of progression in carotid IMT and plaque; multivariate models were adjusted for age, hypertension and total cholesterol to high-density lipoprotein ratio. RESULTS: The mean±SD follow-up time was 5.35±0.60 years in cases and 5.62±0.66 years in controls. The mean IMT change per year was 0.008±0.015 mm in cases and 0.005±0.019 mm in controls (p=0.24). At follow-up, 31.5% of cases and 15% of controls had plaque progression, with a relative risk for plaque progression of 2.09 (95% CI 1.30 to 3.37). In SLE cases, higher fasting glucose and lower fibrinogen were associated with IMT progression after adjustment. Larger waist circumference and non-use of hydroxychloroquine were associated with plaque progression after adjustment. CONCLUSION: Potential modifiable risk factors for carotid IMT and plaque progression in women with SLE were identified, suggesting that monitoring of glucose and waist circumference and use of hydroxychloroquine may be beneficial.


Assuntos
Doenças das Artérias Carótidas , Lúpus Eritematoso Sistêmico , Placa Aterosclerótica , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/epidemiologia , Doenças das Artérias Carótidas/etiologia , Espessura Intima-Media Carotídea , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/epidemiologia , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Fatores de Risco
12.
Front Cardiovasc Med ; 8: 682027, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307496

RESUMO

Cardiovascular magnetic resonance (CMR) imaging is a versatile tool that has established itself as the reference method for functional assessment and tissue characterisation. CMR helps to diagnose, monitor disease course and sub-phenotype disease states. Several emerging CMR methods have the potential to offer a personalised medicine approach to treatment. CMR tissue characterisation is used to assess myocardial oedema, inflammation or thrombus in various disease conditions. CMR derived scar maps have the potential to inform ablation therapy-both in atrial and ventricular arrhythmias. Quantitative CMR is pushing boundaries with motion corrections in tissue characterisation and first-pass perfusion. Advanced tissue characterisation by imaging the myocardial fibre orientation using diffusion tensor imaging (DTI), has also demonstrated novel insights in patients with cardiomyopathies. Enhanced flow assessment using four-dimensional flow (4D flow) CMR, where time is the fourth dimension, allows quantification of transvalvular flow to a high degree of accuracy for all four-valves within the same cardiac cycle. This review discusses these emerging methods and others in detail and gives the reader a foresight of how CMR will evolve into a powerful clinical tool in offering a precision medicine approach to treatment, diagnosis, and detection of disease.

13.
Adv Mater Interfaces ; 5(24): 1800836, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30613462

RESUMO

For decades, fabrication of semiconductor devices has utilized well-established etching techniques to create complex nanostructures in silicon. The most common dry process is reactive ion etching which fabricates nanostructures through the selective removal of unmasked silicon. Generalized enhancements of etching have been reported with mask-enhanced etching with Al, Cr, Cu, and Ag masks, but there is a lack of reports exploring the ability of metallic films to catalytically enhance the local etching of silicon in plasmas. Here, metal-assisted plasma etching (MAPE) is performed using patterned nanometers-thick gold films to catalyze the etching of silicon in an SF6/O2 mixed plasma, selectively increasing the rate of etching by over 1000%. The catalytic enhancement of etching requires direct Si-metal interfacial contact, similar to metal-assisted chemical etching (MACE), but is different in terms of the etching mechanism. The mechanism of MAPE is explored by characterizing the degree of enhancement as a function of Au catalyst configuration and relative oxygen feed concentration, along with the catalytic activities of other common MACE metals including Ag, Pt, and Cu.

14.
eNeuro ; 5(1)2018.
Artigo em Inglês | MEDLINE | ID: mdl-29302617

RESUMO

Mild traumatic brain injuries (mTBIs) are one of the most prevalent neurological disorders, and humans are severely limited in their ability to repair and regenerate central nervous system (CNS) tissue postinjury. However, zebrafish (Danio rerio) maintain the remarkable ability to undergo complete and functional neuroregeneration as an adult. We wish to extend knowledge of the known mechanisms of neuroregeneration by analyzing the differentially expressed genes (DEGs) in a novel adult zebrafish model of mTBI. In this study, a rodent weight drop model of mTBI was adapted to the adult zebrafish. A memory test showed significant deficits in spatial memory in the mTBI group. We identified DEGs at 3 and 21 days postinjury (dpi) through RNA-sequencing analysis. The resulting DEGs were categorized according to gene ontology (GO) categories. At 3 dpi, GO categories consisted of peak injury response pathways. Significantly, at 21 dpi, GO categories consisted of neuroregeneration pathways. Ultimately, these results validate a novel zebrafish model of mTBI and elucidate significant DEGs of interest in CNS injury and neuroregeneration.


Assuntos
Concussão Encefálica/genética , Encéfalo/fisiologia , Regeneração , Animais , Modelos Animais de Doenças , Feminino , Proteínas de Peixes/genética , Expressão Gênica , Ontologia Genética , Masculino , Memória Espacial , Peixe-Zebra
15.
Am J Cardiol ; 120(9): 1495-1500, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28917493

RESUMO

Mental stress-induced myocardial ischemia is common and a prognostic factor of adverse cardiovascular outcomes in patients with coronary artery disease (CAD). The present study aimed at examining associations between mental stress-induced myocardial annular velocity (MAV) and cardiovascular outcome in patients with CAD. MAV, specifically, diastolic early (e'), diastolic late (a'), and systolic (s') velocities were obtained at rest and during mental stress testing in 224 patients with clinically stable CAD. Using Cox regression models, age, sex, and baseline-adjusted mental stress-induced MAV measures were examined as predictors of a priori defined composite event term that comprised all-cause mortality and/or nonfatal cardiovascular events, resulting in an unplanned hospitalization (major adverse cardiovascular events [MACE]). Median follow-up was 4 years. The sample was predominantly male, Caucasian with New York Heart Association functional class I and a mean age of 63 ± 10.2 years. MS-induced changes in e' (hazard ratio [HR] = .73) and s' (HR = .73) were significant (p <0.05) predictors of MACE, and the change in a' (HR = .74) was marginal (p = 0.05). The pattern of the relation for each MAV measure was such that patients with a greater decrease in e' and/or s' velocity had a higher probability of experiencing an MACE, and the association of the change in a' and MACE was marginal (p = 0.05), but the same tendency. The associations between MS-induced values of e' and a' for MACE were independent of resting levels. Mental stress-induced MAV changes independently predict an adverse cardiovascular outcome in patients with stable CAD.


Assuntos
Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/psicologia , Valvas Cardíacas/fisiopatologia , Estresse Psicológico/fisiopatologia , Idoso , Antidepressivos de Segunda Geração/uso terapêutico , Velocidade do Fluxo Sanguíneo/fisiologia , Citalopram/uso terapêutico , Doença da Artéria Coronariana/complicações , Diástole/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estresse Psicológico/complicações , Estresse Psicológico/tratamento farmacológico , Sístole/fisiologia , Resultado do Tratamento
16.
Eur J Prev Cardiol ; 24(6): 591-599, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28067532

RESUMO

Aims Mental stress-induced myocardial ischemia (MSIMI) occurs in up to 70% of patients with clinically stable ischemic heart disease and is associated with increased risk of adverse prognosis. We aimed to examine the prognostic value of indices of MSIMI and exercise stress-induced myocardial ischemia (ESIMI) in a population of ischemic heart disease patients that was not confined by having a recent positive physical stress test. Methods and results The Responses of Mental Stress Induced Myocardial Ischemia to Escitalopram Treatment (REMIT) study enrolled 310 subjects who underwent mental and exercise stress testing and were followed annually for a median of four years. Study endpoints included time to first and total rate of major adverse cardiovascular events, defined as all-cause mortality and hospitalizations for cardiovascular causes. Cox and negative binomial regression adjusting for age, sex, resting left ventricular ejection fraction, and heart failure status were used to examine associations of indices of MSIMI and ESIMI with study endpoints. The continuous variable of mental stress-induced left ventricular ejection fraction change was significantly associated with both endpoints (all p values < 0.05). For every reduction of 5% in left ventricular ejection fraction induced by mental stress, patients had a 5% increase in the probability of a major adverse cardiovascular event at the median follow-up time and a 20% increase in the number of major adverse cardiovascular events endured over the follow-up period of six years. Indices of ESIMI did not predict endpoints ( ps > 0.05). Conclusion In patients with stable ischemic heart disease, mental, but not exercise, stress-induced left ventricular ejection fraction change significantly predicts risk of future adverse cardiovascular events.


Assuntos
Saúde Mental , Isquemia Miocárdica/complicações , Estresse Psicológico/complicações , Volume Sistólico , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda , Idoso , Citalopram/uso terapêutico , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/fisiopatologia , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Estresse Psicológico/diagnóstico , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/psicologia , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia
17.
Mol Cancer Res ; 15(10): 1318-1330, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28710231

RESUMO

Tuberous sclerosis complex (TSC) is a tumor-suppressor syndrome affecting multiple organs, including the brain, skin, kidneys, heart, and lungs. TSC is associated with mutations in TSC1 or TSC2, resulting in hyperactivation of mTOR complex 1 (mTORC1). Clinical trials demonstrate that mTORC1 inhibitors decrease tumor volume and stabilize lung function in TSC patients; however, mTOR inhibitors are cytostatic not cytocidal, and long-term benefits and toxicities are uncertain. Previously, we identified rapamycin-insensitive upregulation of cyclooxygenase 2 (PTGS2/COX2) and prostaglandin E2 (PGE2) production in TSC2-deficient cells and postulated that the action of excess PGE2 and its cognate receptors (EP) contributes to cell survival. In this study, we identify upregulation of EP3 (PTGER3) expression in TSC2-deficient cells, TSC renal angiomyolipomas, lymphangioleiomyomatosis lung nodules, and epileptic brain tubers. TSC2 negatively regulated EP3 expression via Rheb in a rapamycin-insensitive manner. The EP3 antagonist, L-798106, selectively suppressed the viability of TSC2-deficient cells in vitro and decreased the lung colonization of TSC2-deficient cells. Collectively, these data reveal a novel function of TSC2 and Rheb in the regulation of EP3 expression and cell viability.Implications: Therapeutic targeting of an aberrant PGE2-EP3 signaling axis may have therapeutic benefit for TSC patients and for other mTOR-hyperactive neoplasms. Mol Cancer Res; 15(10); 1318-30. ©2017 AACR.


Assuntos
Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Receptores de Prostaglandina E Subtipo EP3/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Angiomiolipoma/genética , Angiomiolipoma/metabolismo , Animais , Encéfalo/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Criança , Pré-Escolar , Epilepsia/genética , Epilepsia/metabolismo , Feminino , Humanos , Lactente , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Linfangioleiomiomatose/genética , Linfangioleiomiomatose/metabolismo , Masculino , Camundongos , Mutação , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacologia , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/deficiência , Regulação para Cima
18.
Clin Colorectal Cancer ; 15(3): 257-63, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26803708

RESUMO

BACKGROUND: Capecitabine is used to treat colorectal (CRC) cancer. TRIO-013, a study examining capecitabine/oxaliplatin ± lapatinib in metastatic gastro-esophageal cancer did not show increases in overall survival (OS) with lapatinib. An analysis showed concurrent proton pump inhibitor (PPI) usage negatively impacted recurrence-free survival (RFS). We retrospectively studied PPI effects on capecitabine efficacy in early stage CRC and how capecitabine adjustments impacted RFS. METHODS: Early stage CRC patients taking monotherapy capecitabine treated from 2008 to 2012 were reviewed for demographics, medications, toxicities, and patient outcomes. RESULTS: Of 298 identified patients, 25.8% (n = 77) received concurrent PPIs. Five-year RFS was 74% versus 83% (hazard ratio [HR], 1.89; 95% confidence interval [CI], 1.07-3.35; P = .03) in PPI versus non-PPI patients respectively. OS was 81% versus 78%, respectively (HR, 1.13; 95% CI, 0.60-2.14; P = .7). After accounting for gender, stage, age, and performance status, PPI patients tended toward decreased RFS (HR, 1.65; 95% CI, 0.93-2.94; P = .09). Capecitabine dose modifications affected outcomes. Five-year RFS was 84% in the control group, 100% in the treatment-delay group (P = .99), 67% in the dose reduction group (HR, 2.46; 95% CI, 1.23-4.93; P = .01), and 64% in the discontinuation group (HR, 2.27; 95% CI, 0.93-5.53; P = .07). Five-year OS was significantly less in the discontinuation group than control group (59% vs. 82%; HR, 3.27; 95% CI, 1.44-7.45; P = .005). CONCLUSIONS: PPIs appear to impact RFS; this may be due to PPIs preventing capecitabine tablet dissolution and absorption. Patients with dose reductions or who stopped treatment had worse outcomes than patients who continued with treatment at starting doses.


Assuntos
Antineoplásicos/uso terapêutico , Capecitabina/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Recidiva Local de Neoplasia , Inibidores da Bomba de Prótons/efeitos adversos , Adulto , Idoso , Neoplasias Colorretais/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/mortalidade , Modelos de Riscos Proporcionais , Estudos Retrospectivos
19.
JCI Insight ; 1(19): e86629, 2016 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-27882343

RESUMO

Lymphangioleiomyomatosis (LAM) is a progressive lung disease that primarily affects young women. Genetic evidence suggests that LAM cells bearing TSC2 mutations migrate to the lungs, proliferate, and cause cystic remodeling. The female predominance indicates that estrogen plays a critical role in LAM pathogenesis, and we have proposed that estrogen promotes LAM cell metastasis by inhibition of anoikis. We report here that estrogen increased LAM patient-derived cells' resistance to anoikis in vitro, accompanied by decreased accumulation of the proapoptotic protein Bim, an activator of anoikis. The resistance to anoikis was reversed by the proteasome inhibitor, bortezomib. Treatment of LAM patient-derived cells with estrogen plus bortezomib promoted anoikis compared with estrogen alone. Depletion of Bim by siRNA in TSC2-deficient cells resulted in anoikis resistance. Treatment of mice with bortezomib reduced estrogen-promoted lung colonization of TSC2-deficient cells. Importantly, molecular depletion of Bim by siRNA in Tsc2-deficient cells increased lung colonization in a mouse model. Collectively, these data indicate that Bim plays a key role in estrogen-enhanced survival of LAM patient-derived cells under detached conditions that occur with dissemination. Thus, targeting Bim may be a plausible future treatment strategy in patients with LAM.


Assuntos
Anoikis , Proteína 11 Semelhante a Bcl-2/metabolismo , Estrogênios/fisiologia , Pneumopatias/patologia , Linfangioleiomiomatose/patologia , Proteínas Supressoras de Tumor/genética , Animais , Bortezomib/farmacologia , Feminino , Humanos , Pulmão/citologia , Camundongos , Camundongos SCID , Proteína 2 do Complexo Esclerose Tuberosa , Células Tumorais Cultivadas
20.
Adv Healthc Mater ; 4(14): 2090-2099, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26270898

RESUMO

Chronic skin ulcerations are a common complication of diabetes mellitus, affecting up to one in four diabetic individuals. Despite the prevalence of these wounds, current pharmacologic options for treating them remain limited. Growth factor-based therapies have displayed a mixed ability to drive successful healing, which may be due to nonoptimal delivery strategies. Here, a method for coating commercially available nylon dressings using the layer-by-layer process is described to enable both sustained release and independent control over the release kinetics of vascular endothelial growth factor 165 and platelet-derived growth factor BB. It is shown that the use of strategically spaced diffusion barriers formed spontaneously by disulfide bonds enables independent control over the release rates of incorporated growth factors, and that in vivo these dressings improve several aspects of wound healing in db/db mice.

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