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1.
Hum Brain Mapp ; 45(5): e26675, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38590155

RESUMO

Isolated REM sleep behavior disorder (iRBD) is an early stage of synucleinopathy with most patients progressing to Parkinson's disease (PD) or related conditions. Quantitative susceptibility mapping (QSM) in PD has identified pathological iron accumulation in the substantia nigra (SN) and variably also in basal ganglia and cortex. Analyzing whole-brain QSM across iRBD, PD, and healthy controls (HC) may help to ascertain the extent of neurodegeneration in prodromal synucleinopathy. 70 de novo PD patients, 70 iRBD patients, and 60 HCs underwent 3 T MRI. T1 and susceptibility-weighted images were acquired and processed to space standardized QSM. Voxel-based analyses of grey matter magnetic susceptibility differences comparing all groups were performed on the whole brain and upper brainstem levels with the statistical threshold set at family-wise error-corrected p-values <.05. Whole-brain analysis showed increased susceptibility in the bilateral fronto-parietal cortex of iRBD patients compared to both PD and HC. This was not associated with cortical thinning according to the cortical thickness analysis. Compared to iRBD, PD patients had increased susceptibility in the left amygdala and hippocampal region. Upper brainstem analysis revealed increased susceptibility within the bilateral SN for both PD and iRBD compared to HC; changes were located predominantly in nigrosome 1 in the former and nigrosome 2 in the latter group. In the iRBD group, abnormal dopamine transporter SPECT was associated with increased susceptibility in nigrosome 1. iRBD patients display greater fronto-parietal cortex involvement than incidental early-stage PD cohort indicating more widespread subclinical neuropathology. Dopaminergic degeneration in the substantia nigra is paralleled by susceptibility increase, mainly in nigrosome 1.


Assuntos
Doença de Parkinson , Transtorno do Comportamento do Sono REM , Sinucleinopatias , Humanos , Transtorno do Comportamento do Sono REM/diagnóstico por imagem , Sinucleinopatias/complicações , Sinucleinopatias/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Doença de Parkinson/complicações , Ferro
2.
J Mater Chem C Mater ; 12(15): 5339-5346, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38645749

RESUMO

Organic electrochemical transistors (OECTs) have emerged as promising candidates for various fields, including bioelectronics, neuromorphic computing, biosensors, and wearable electronics. OECTs operate in aqueous solutions, exhibit high amplification properties, and offer ion-to-electron signal transduction. The OECT channel consists of a conducting polymer, with PEDOT:PSS receiving the most attention to date. While PEDOT:PSS is highly conductive, and benefits from optimized protocols using secondary dopants and detergents, new p-type and n-type polymers are emerging with desirable material properties. Among these, low-oxidation potential oligomers are highly enabling for bioelectronics applications, however the polymers resulting from their polymerization lag far behind in conductivity compared with the established PEDOT:PSS. In this work we show that by careful design of the OECT geometrical characteristics, we can overcome this limitation and achieve devices that are on-par with transistors employing PEDOT:PSS. We demonstrate that the vertical architecture allows for facile electropolymerization of a family of trimers that are polymerized in very low oxidation potentials, without the need for harsh chemicals or secondary dopants. Vertical and planar OECTs are compared using various characterization methods. We show that vOECTs are superior platforms in general and propose that the vertical architecture can be expanded for the realization of OECTs for various applications.

3.
mSystems ; 9(4): e0116523, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38530056

RESUMO

To establish infections in human hosts, Pseudomonas aeruginosa must overcome innate immune-generated oxidative stress, such as the hypochlorous acid (HOCl) produced by neutrophils. We set out to find specific biomarkers of oxidative stress through the development of a protocol for the metabolic profiling of P. aeruginosa cultures grown in the presence of different oxidants using a novel ionization technique for mass spectrometry, laser desorption rapid evaporative ionization mass spectrometry (LD-REIMS). We demonstrated the ability of LD-REIMS to classify samples as untreated or treated with a specific oxidant with 100% accuracy and identified a panel of 54 metabolites with significantly altered concentrations after exposure to one or more of the oxidants. Key metabolic changes were conserved in P. aeruginosa clinical strains isolated from patients with cystic fibrosis lung infections. These data demonstrated that HOCl stress impacted the Pseudomonas quinolone signal (PQS) quorum sensing system. Ten 2-alkyl-4-quinolones (AHQs) associated with the PQS system were significantly lower in concentration in HOCl-stressed P. aeruginosa cultures, including 2-heptyl-3-hydroxy-4(1H)-quinolone (PQS), the most active signal molecule of the PQS system. The PQS system regulates the production of virulence factors, including pyocyanin and elastase, and their levels were markedly affected by HOCl stress. No pyocyanin was detectable and elastase concentrations were reduced by more than 75% in cultures grown with sub-lethal concentrations of HOCl, suggesting that this neutrophil-derived oxidant may disrupt the ability of P. aeruginosa to establish infections through interference with production of PQS-associated virulence factors. IMPORTANCE: This work demonstrates that a high-throughput ambient ionization mass spectrometry method can be used successfully to study a bacterial stress response. Its application to the opportunistic pathogen Pseudomonas aeruginosa led to the identification of specific oxidative stress biomarkers, and demonstrated that hypochlorous acid, an oxidant specifically produced by human neutrophils during infection, affects quorum sensing and reduces production of the virulence factors pyocyanin and elastase. No pyocyanin was detectable and elastase levels were reduced by more than 75% in bacteria grown in the presence of hypochlorous acid. This approach has the potential to be widely applicable to the characterization of the stress responses of bacteria.


Assuntos
Quinolonas , Percepção de Quorum , Humanos , Pseudomonas aeruginosa , Ácido Hipocloroso/metabolismo , Piocianina/metabolismo , Quinolonas/análise , Fatores de Virulência/metabolismo , Espectrometria de Massas , Oxidantes/metabolismo , Elastase Pancreática/metabolismo , Biomarcadores/metabolismo , Lasers
4.
J Control Release ; 369: 668-683, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38548064

RESUMO

Local and long-lasting administration of potent chemotherapeutics is a promising therapeutic intervention to increase the efficiency of chemotherapy of hard-to-treat tumors such as the most lethal brain tumors, glioblastomas (GBM). However, despite high toxicity for GBM cells, potent chemotherapeutics such as gemcitabine (Gem) cannot be widely implemented as they do not efficiently cross the blood brain barrier (BBB). As an alternative method for continuous administration of Gem, we here operate freestanding iontronic pumps - "GemIPs" - equipped with a custom-synthesized ion exchange membrane (IEM) to treat a GBM tumor in an avian embryonic in vivo system. We compare GemIP treatment effects with a topical metronomic treatment and observe that a remarkable growth inhibition was only achieved with steady dosing via GemIPs. Daily topical drug administration (at the maximum dosage that was not lethal for the embryonic host organism) did not decrease tumor sizes, while both treatment regimes caused S-phase cell cycle arrest and apoptosis. We hypothesize that the pharmacodynamic effects generate different intratumoral drug concentration profiles for each technique, which causes this difference in outcome. We created a digital model of the experiment, which proposes a fast decay in the local drug concentration for the topical daily treatment, but a long-lasting high local concentration of Gem close to the tumor area with GemIPs. Continuous chemotherapy with iontronic devices opens new possibilities in cancer treatment: the long-lasting and highly local dosing of clinically available, potent chemotherapeutics to greatly enhance treatment efficiency without systemic side-effects. SIGNIFICANCE STATEMENT: Iontronic pumps (GemIPs) provide continuous and localized administration of the chemotherapeutic gemcitabine (Gem) for treating glioblastoma in vivo. By generating high and constant drug concentrations near the vascularized growing tumor, GemIPs offer an efficient and less harmful alternative to systemic administration. Continuous GemIP dosing resulted in remarkable growth inhibition, superior to daily topical Gem application at higher doses. Our digital modelling shows the advantages of iontronic chemotherapy in overcoming limitations of burst release and transient concentration profiles, and providing precise control over dosing profiles and local distribution. This technology holds promise for future implants, could revolutionize treatment strategies, and offers a new platform for studying the influence of timing and dosing dependencies of already-established drugs in the fight against hard-to-treat tumors.

5.
Front Physiol ; 15: 1327407, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384795

RESUMO

Introduction: Magnetic resonance elastography (MRE) is a non-invasive method to quantify biomechanical properties of human tissues. It has potential in diagnosis and monitoring of kidney disease, if established in clinical practice. The interplay of flow and volume changes in renal vessels, tubule, urinary collection system and interstitium is complex, but physiological ranges of in vivo viscoelastic properties during fasting and hydration have never been investigated in all gross anatomical segments simultaneously. Method: Ten healthy volunteers underwent two imaging sessions, one following a 12-hour fasting period and the second after a drinking challenge of >10 mL per kg body weight (60-75 min before the second examination). High-resolution renal MRE was performed using a novel driver with rotating eccentric mass placed at the posterior-lateral wall to couple waves (50 Hz) to the kidney. The biomechanical parameters, shear wave speed (cs in m/s), storage modulus (Gd in kPa), loss modulus (Gl in kPa), phase angle (Υ=2πatanGlGd) and attenuation (α in 1/mm) were derived. Accurate separation of gross anatomical segments was applied in post-processing (whole kidney, cortex, medulla, sinus, vessel). Results: High-quality shear waves coupled into all gross anatomical segments of the kidney (mean shear wave displacement: 163 ± 47 µm, mean contamination of second upper harmonics <23%, curl/divergence: 4.3 ± 0.8). Regardless of the hydration state, median Gd of the cortex and medulla (0.68 ± 0.11 kPa) was significantly higher than that of the sinus and vessels (0.48 ± 0.06 kPa), and consistently, significant differences were found in cs, Υ, and Gl (all p < 0.001). The viscoelastic parameters of cortex and medulla were not significantly different. After hydration sinus exhibited a small but significant reduction in median Gd by -0.02 ± 0.04 kPa (p = 0.01), and, consequently, the cortico-sinusoidal-difference in Gd increased by 0.04 ± 0.07 kPa (p = 0.05). Only upon hydration, the attenuation in vessels became lower (0.084 ± 0.013 1/mm) and differed significantly from the whole kidney (0.095 ± 0.007 1/mm, p = 0.01). Conclusion: High-resolution renal MRE with an innovative driver and well-defined 3D segmentation can resolve all renal segments, especially when including the sinus in the analysis. Even after a prolonged hydration period the approach is sensitive to small hydration-related changes in the sinus and in the cortico-sinusoidal-difference.

6.
J Endourol ; 38(4): 331-339, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38269428

RESUMO

Background: Radical cystectomy (RC) is standard of care for muscle-invasive bladder cancer, but it comes with significant perioperative risk, with half of the patients experiencing major postoperative complications. Robot-assisted radical cystectomies (RARCs) have aimed to decrease patient morbidity and been increasingly adopted in North America. Currently, both open radical cystectomies (ORCs) and RARCs are frequently performed. The aim of this study is to contribute to the existing literature using newly available data from the American College of Surgeons National Surgical Quality Improvement Project (NSQIP), representing one of the most recent, largest multi-institutional studies, while uniquely accounting for a variety of factors, including type of urinary diversion, cancer staging, and neoadjuvant chemotherapy. Methods: RC procedures performed between 2019 and 2021 were identified in NSQIP and the corresponding cystectomy-targeted database. Cases in the ORC group were planned open procedures, and cases in the RARC group were robot assisted, including unplanned conversion to open cases for intention to treat. Chi-square and t-tests were performed to compare baseline demographics and operative parameters. Multivariate analysis was performed for outcomes, including major complications, minor complications, and 30-day mortality rates, while adjusting for baseline differences significant on univariate analysis. Results: Five thousand three hundred forty-three RC cases were identified. Of these, 70% underwent planned ORC, while 30% received RARC. RARC was associated with longer operative times and shorter hospital length of stay compared with ORC. On multivariate analysis, there was no difference between the cohorts in 30-day rates of major complications, hospital readmissions, need for reoperation, or mortality. ORC was, however, associated with higher rates of minor complications, bleeding, superficial surgical site infections, and anastomotic leak. Conclusions: In the NSQIP database, ORC is associated with higher rates of 30-day minor complications, most notably bleeding, compared with RARC. However, there is no difference in regard to perioperative major morbidity or mortality rates. This study is unique in the size of the cohorts compared, timeliness of data (2019-2021), applicability to a variety of different practice settings across the country, and ability to control for factors, such as type of urinary diversion and pathological bladder cancer staging, as well as use of neoadjuvant chemotherapy. This study was approved by the Institutional Review Board (IRB) specific to Thomas Jefferson University.


Assuntos
Procedimentos Cirúrgicos Robóticos , Neoplasias da Bexiga Urinária , Humanos , Cistectomia/efeitos adversos , Cistectomia/métodos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Melhoria de Qualidade , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia
7.
Magn Reson Med ; 91(5): 2044-2056, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38193276

RESUMO

PURPOSE: Subject movement during the MR examination is inevitable and causes not only image artifacts but also deteriorates the homogeneity of the main magnetic field (B0 ), which is a prerequisite for high quality data. Thus, characterization of changes to B0 , for example induced by patient movement, is important for MR applications that are prone to B0 inhomogeneities. METHODS: We propose a deep learning based method to predict such changes within the brain from the change of the head position to facilitate retrospective or even real-time correction. A 3D U-net was trained on in vivo gradient-echo brain 7T MRI data. The input consisted of B0 maps and anatomical images at an initial position, and anatomical images at a different head position (obtained by applying a rigid-body transformation on the initial anatomical image). The output consisted of B0 maps at the new head positions. We further fine-trained the network weights to each subject by measuring a limited number of head positions of the given subject, and trained the U-net with these data. RESULTS: Our approach was compared to established dynamic B0 field mapping via interleaved navigators, which suffer from limited spatial resolution and the need for undesirable sequence modifications. Qualitative and quantitative comparison showed similar performance between an interleaved navigator-equivalent method and proposed method. CONCLUSION: It is feasible to predict B0 maps from rigid subject movement and, when combined with external tracking hardware, this information could be used to improve the quality of MR acquisitions without the use of navigators.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Movimento (Física) , Movimento , Processamento de Imagem Assistida por Computador/métodos , Artefatos
8.
Magn Reson Med ; 91(5): 1834-1862, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38247051

RESUMO

This article provides recommendations for implementing QSM for clinical brain research. It is a consensus of the International Society of Magnetic Resonance in Medicine, Electro-Magnetic Tissue Properties Study Group. While QSM technical development continues to advance rapidly, the current QSM methods have been demonstrated to be repeatable and reproducible for generating quantitative tissue magnetic susceptibility maps in the brain. However, the many QSM approaches available have generated a need in the neuroimaging community for guidelines on implementation. This article outlines considerations and implementation recommendations for QSM data acquisition, processing, analysis, and publication. We recommend that data be acquired using a monopolar 3D multi-echo gradient echo (GRE) sequence and that phase images be saved and exported in Digital Imaging and Communications in Medicine (DICOM) format and unwrapped using an exact unwrapping approach. Multi-echo images should be combined before background field removal, and a brain mask created using a brain extraction tool with the incorporation of phase-quality-based masking. Background fields within the brain mask should be removed using a technique based on SHARP or PDF, and the optimization approach to dipole inversion should be employed with a sparsity-based regularization. Susceptibility values should be measured relative to a specified reference, including the common reference region of the whole brain as a region of interest in the analysis. The minimum acquisition and processing details required when reporting QSM results are also provided. These recommendations should facilitate clinical QSM research and promote harmonized data acquisition, analysis, and reporting.


Assuntos
Encéfalo , Processamento de Imagem Assistida por Computador , Consenso , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Cabeça , Imageamento por Ressonância Magnética/métodos , Algoritmos , Mapeamento Encefálico/métodos
9.
J Health Soc Behav ; : 221465231223723, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38235534

RESUMO

We investigate recent trends in U.S. suicide mortality using a "structural determinants of health" framework. We access restricted-use multiple cause of death files to track suicide rates among U.S. Black, White, American Indian/Alaska Native, and Latino/a men and women between 1990 and 2017. We examine suicide deaths separately by poisonings and nonpoisonings to illustrate that (1) women's suicide rates from poisonings track strongly with increases in prescription drug availability and (2) nonpoisoning suicide rates among all adult Americans track strongly with worsening economic conditions coinciding with the financial crash and Great Recession. These findings suggest that institutional failures elevated U.S. suicide risk between 1990 and 2017 by increasing access to more lethal means of self-harm and by increasing both exposure and vulnerability to economic downturns. Together, these results support calls to scale up to focus on the structural determinants of U.S. suicide.

10.
Sci Adv ; 10(3): eadj1984, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38241380

RESUMO

Precise manipulation of flexible surgical tools is crucial in minimally invasive surgical procedures, necessitating a miniature and flexible robotic probe that can precisely direct the surgical instruments. In this work, we developed a polymer-based robotic fiber with a thermal actuation mechanism by local heating along the sides of a single fiber. The fiber robot was fabricated by highly scalable fiber drawing technology using common low-cost materials. This low-profile (below 2 millimeters in diameter) robotic fiber exhibits remarkable motion precision (below 50 micrometers) and repeatability. We developed control algorithms coupling the robot with endoscopic instruments, demonstrating high-resolution in situ molecular and morphological tissue mapping. We assess its practicality and safety during in vivo laparoscopic surgery on a porcine model. High-precision motion of the fiber robot delivered endoscopically facilitates the effective use of cellular-level intraoperative tissue identification and ablation technologies, potentially enabling precise removal of cancer in challenging surgical sites.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Robótica , Suínos , Animais , Procedimentos Cirúrgicos Robóticos/métodos , Laparoscopia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos
11.
Artigo em Inglês | MEDLINE | ID: mdl-38141020

RESUMO

We demonstrate an organic electrochemical transistor (OECT) biosensor for the detection of interleukin 6 (IL6), an important biomarker associated with various pathological processes, including chronic inflammation, inflammaging, cancer, and severe COVID-19 infection. The biosensor is functionalized with oligonucleotide aptamers engineered to bind specifically IL6. We developed an easy functionalization strategy based on gold nanoparticles deposited onto a poly(3,4-ethylenedioxythiophene) doped with polystyrenesulfonate (PEDOT:PSS) gate electrode for the subsequent electrodeposition of thiolated aptamers. During this functionalization step, the reduction of sulfide bonds allows for simultaneous deposition of a blocking agent. A detection range from picomolar to nanomolar concentrations for IL6 was achieved, and the selectivity of the device was assessed against Tumor Necrosis Factor (TNF), another cytokine involved in the inflammatory processes.

12.
Neuroimage ; 283: 120419, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37871759

RESUMO

Quantitative Susceptibility Mapping has the potential to provide additional insights into neurological diseases but is typically based on a quite long (5-10 min) 3D gradient-echo scan which is highly sensitive to motion. We propose an ultra-fast acquisition based on three orthogonal (sagittal, coronal and axial) 2D simultaneous multi-slice EPI scans with 1 mm in-plane resolution and 3 mm thick slices. Images in each orientation are corrected for susceptibility-related distortions and co-registered with an iterative non-linear Minimum Deformation Averaging (Volgenmodel) approach to generate a high SNR, super-resolution data set with an isotropic resolution of close to 1 mm. The net acquisition time is 3 times the volume acquisition time of EPI or about 12 s, but the three volumes could also replace "dummy scans" in fMRI, making it feasible to acquire QSM in little or No Additional Time for Imaging (NATIve). NATIve QSM values agreed well with reference 3D GRE QSM in the basal ganglia in healthy subjects. In patients with multiple sclerosis, there was also a good agreement between the susceptibility values within lesions and control ROIs and all lesions which could be seen on 3D GRE QSMs could also be visualized on NATIve QSMs. The approach is faster than conventional 3D GRE by a factor of 25-50 and faster than 3D EPI by a factor of 3-5. As a 2D technique, NATIve QSM was shown to be much more robust to motion than the 3D GRE and 3D EPI, opening up the possibility of studying neurological diseases involving iron accumulation and demyelination in patients who find it difficult to lie still for long enough to acquire QSM data with conventional methods.


Assuntos
Imagem Ecoplanar , Humanos , Imagem Ecoplanar/métodos , Gânglios da Base/diagnóstico por imagem
13.
Int J Immunogenet ; 50(5): 249-255, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37658479

RESUMO

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease. Chronic HCV infection is also an important cause of hepatic fibrosis, cirrhosis and hepatocellular carcinoma (HCC). HCV has the capacity to evade immune surveillance by altering the host immune response. Moreover, variations in immune-related genes can lead to differential susceptibility to HCV infection as well as interfere on the susceptibility to the development of hepatic fibrosis, cirrhosis and HCC. The human leucocyte antigen G (HLA-G) gene codes for an immunomodulatory protein known to be expressed in the maternal-foetal interface and in immune-privileged tissues. The HLA-G 3' untranslated region (3'UTR) is important for mRNA stability, and variants in this region are known to impact gene expression. Studies, mainly focusing in a 14 bp insertion/deletion polymorphism, have correlated HLA-G 3'UTR with susceptibility to viral infections, but other polymorphic variants in the HLA-G 3'UTR might also affect HCV infection as they are inherited as haplotypes. The present study evaluated HLA-G 3'UTR polymorphisms and performed linkage disequilibrium test and haplotype assembly in 286 HCV infected patients who have developed fibrosis, cirrhosis or HCC, as well as in 129 healthy control subjects. Haplotypes UTR-1, UTR-2 and UTR-3 were the most observed in HCV+ patients, in the frequencies of 0.276, 0.255 and 0.121, respectively. No statistically significant difference was observed between HCV+ and control subjects, even when patients were grouped according to outcome (HCC, cirrhosis or fibrosis). Despite that, some trends in the results were observed, and therefore, we cannot rule out the possibility that variants associated to high HLA-G expression can be involved in HCV infection susceptibility.


Assuntos
Carcinoma Hepatocelular , Hepatite C , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Regiões 3' não Traduzidas/genética , Hepacivirus , Antígenos HLA-G/genética , Haplótipos/genética , Neoplasias Hepáticas/genética , Cirrose Hepática/genética , Hepatite C/complicações , Hepatite C/genética
14.
Hum Brain Mapp ; 44(15): 5095-5112, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37548414

RESUMO

The boundaries between tissues with different magnetic susceptibilities generate inhomogeneities in the main magnetic field which change over time due to motion, respiration and system instabilities. The dynamically changing field can be measured from the phase of the fMRI data and corrected. However, methods for doing so need multi-echo data, time-consuming reference scans and/or involve error-prone processing steps, such as phase unwrapping, which are difficult to implement robustly on the MRI host. The improved dynamic distortion correction method we propose is based on the phase of the single-echo EPI data acquired for fMRI, phase offsets calculated from a triple-echo, bipolar reference scan of circa 3-10 s duration using a method which avoids the need for phase unwrapping and an additional correction derived from one EPI volume in which the readout direction is reversed. This Reverse-Encoded First Image and Low resoLution reference scan (REFILL) approach is shown to accurately measure B0 as it changes due to shim, motion and respiration, even with large dynamic changes to the field at 7 T, where it led to a > 20% increase in time-series signal to noise ratio compared to data corrected with the classic static approach. fMRI results from REFILL-corrected data were free of stimulus-correlated distortion artefacts seen when data were corrected with static field mapping. The method is insensitive to shim changes and eddy current differences between the reference scan and the fMRI time series, and employs calculation steps that are simple and robust, allowing most data processing to be performed in real time on the scanner image reconstruction computer. These improvements make it feasible to routinely perform dynamic distortion correction in fMRI.


Assuntos
Mapeamento Encefálico , Encéfalo , Imagem Ecoplanar , Humanos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imagem Ecoplanar/métodos , Artefatos
15.
Struct Heart ; 7(4): 100182, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37520136

RESUMO

Background: Inflammation and thrombosis are often linked mechanistically and are associated with adverse events after transcatheter aortic valve replacement (TAVR). High residual platelet reactivity (HRPR) is especially common when clopidogrel is used in this setting, but its relevance to immune activation is unknown. We sought to determine whether residual activity at the purinergic receptor P2Y12 (P2Y12) promotes prothrombotic immune activation in the setting of TAVR. Methods: This was a randomized trial of 60 patients (enrolled July 2015 through December 2018) assigned to clopidogrel (300mg load, 75mg daily) or ticagrelor (180mg load, 90 mg twice daily) before and for 30 days following TAVR. Co-primary endpoints were P2Y12-dependent platelet activity (Platelet Reactivity Units; VerifyNow) and the proportion of inflammatory (cluster of differentiation [CD] 14+/CD16+) monocytes 1 day after TAVR. Results: Compared to clopidogrel, those randomized to ticagrelor had greater platelet inhibition (median Platelet Reactivity Unit [interquartile range]: (234 [170.0-282.3] vs. 128.5 [86.5-156.5], p < 0.001), but similar inflammatory monocyte proportions (22.2% [18.0%-30.2%] vs. 25.1% [22.1%-31.0%], p = 0.201) 1 day after TAVR. Circulating monocyte-platelet aggregates, soluble CD14 levels, interleukin 6 and 8 levels, and D-dimers were also similar across treatment groups. HRPR was observed in 63% of the clopidogrel arm and was associated with higher inflammatory monocyte proportions. Major bleeding events, pacemaker placement, and mortality did not differ by treatment assignment. Conclusions: Residual P2Y12 activity after TAVR is common in those treated with clopidogrel but ticagrelor does not significantly alter biomarkers of prothrombotic immune activation. HRPR appears to be an indicator (not a cause) of innate immune activation in this setting.

16.
Agri ; 35(3): 153-166, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37493479

RESUMO

OBJECTIVES: Pain Neuroscience Education (PNE) shows improvement in pain and functional capacity in patients with chronic low back pain (CLBP). Therefore, the study aimed to verify if the physiotherapeutic treatment associated with PNE decreases the functional disability of patients with nonspecific CLBP. METHODS: Forty patients were clinically evaluated and answered the following questionnaires: Brief pain inventory, Central Sensitization Inventory (CSI), Roland-Morris disability questionnaire, pain catastrophizing scale, Tampa scale of kinesiophobia, hospital anxiety, and depression scale, SF6D quality of life questionnaire and performed quantitative sensory tests (QSTs). Afterward, they were randomly divided into the intervention group (IG, n=20) and the control group (CG, n=20). Both performed kinesiotherapy exercises twice a week for 6 weeks. The IG received 3 individual PNE sessions and answered the pain neurophysiology questionnaire. RESULTS: IG showed significant improvement for all variables analyzed (p<0.001). The association decreased the kinesiophobia (estimated difference between CG-IG means: 7.6-95% CI: 2.3-12.9) (p=0.006). In the lumbar paravertebral region (CG and IG), there was a statistical difference in the intensity of CLBP in the QSTs (p<0.05). CONCLUSION: The association showed better results compared to only therapeutic exercises to reduce kinesiophobia and change the perception of pain intensity in the lumbar region.


Assuntos
Dor Crônica , Dor Lombar , Humanos , Dor Crônica/terapia , Dor Lombar/terapia , Projetos Piloto , Qualidade de Vida , Método Simples-Cego
17.
Front Immunol ; 14: 1181823, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415975

RESUMO

Objective: It is believed that intestinal recruitment of monocytes from Crohn's Disease (CD) patients who carry NOD2 risk alleles may repeatedly give rise to recruitment of pathogenic macrophages. We investigated an alternative possibility that NOD2 may rather inhibit their differentiation from intravasating monocytes. Design: The monocyte fate decision was examined by using germ-free mice, mixed bone marrow chimeras and a culture system yielding macrophages and monocyte-derived dendritic cells (mo-DCs). Results: We observed a decrease in the frequency of mo-DCs in the colon of Nod2-deficient mice, despite a similar abundance of monocytes. This decrease was independent of the changes in the gut microbiota and dysbiosis caused by Nod2 deficiency. Similarly, the pool of mo-DCs was poorly reconstituted in a Nod2-deficient mixed bone marrow (BM) chimera. The use of pharmacological inhibitors revealed that activation of NOD2 during monocyte-derived cell development, dominantly inhibits mTOR-mediated macrophage differentiation in a TNFα-dependent manner. These observations were supported by the identification of a TNFα-dependent response to muramyl dipeptide (MDP) that is specifically lost when CD14-expressing blood cells bear a frameshift mutation in NOD2. Conclusion: NOD2 negatively regulates a macrophage developmental program through a feed-forward loop that could be exploited for overcoming resistance to anti-TNF therapy in CD.


Assuntos
Doença de Crohn , Monócitos , Animais , Camundongos , Acetilmuramil-Alanil-Isoglutamina/farmacologia , Doença de Crohn/genética , Doença de Crohn/patologia , Macrófagos , Inibidores do Fator de Necrose Tumoral , Fator de Necrose Tumoral alfa
18.
Langmuir ; 39(23): 8196-8204, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37267478

RESUMO

Seamless integration between biological systems and electrical components is essential for enabling a twinned biochemical-electrical recording and therapy approach to understand and combat neurological disorders. Employing bioelectronic systems made up of conjugated polymers, which have an innate ability to transport both electronic and ionic charges, provides the possibility of such integration. In particular, translating enzymatically polymerized conductive wires, recently demonstrated in plants and simple organism systems, into mammalian models, is of particular interest for the development of next-generation devices that can monitor and modulate neural signals. As a first step toward achieving this goal, enzyme-mediated polymerization of two thiophene-based monomers is demonstrated on a synthetic lipid bilayer supported on a Au surface. Microgravimetric studies of conducting films polymerized in situ provide insights into their interactions with a lipid bilayer model that mimics the cell membrane. Moreover, the resulting electrical and viscoelastic properties of these self-organizing conducting polymers suggest their potential as materials to form the basis for novel approaches to in vivo neural therapeutics.


Assuntos
Bicamadas Lipídicas , Polímeros , Animais , Polimerização , Membrana Celular , Membranas , Mamíferos
19.
J Health Soc Behav ; 64(2): 174-191, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37098856

RESUMO

Induction of labor (IOL) rates in the United States have nearly tripled since 1990. We examine official U.S. birth records to document increases in states' IOL rates among pregnancies to Black, Latina, and White women. We test if the increases are associated with changes in demographic characteristics and risk factors among states' racial-ethnic childbearing populations. Among pregnancies to White women, increases in state IOL rates are strongly associated with changes in risk factors among White childbearing populations. However, the rising IOL rates among pregnancies to Black and Latina women are not due to changing factors in their own populations but are instead driven by changing factors among states' White childbearing populations. The results suggest systemic racism may be shaping U.S. obstetric care whereby care is not "centered at the margins" but is instead responsive to characteristics in states' White populations.


Assuntos
Disparidades em Assistência à Saúde , Trabalho de Parto Induzido , Feminino , Humanos , Gravidez , Hispânico ou Latino , Fatores de Risco , Estados Unidos , Negro ou Afro-Americano , Brancos , Racismo
20.
Adv Healthc Mater ; 12(24): e2300550, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37069480

RESUMO

The organic electronic ion pump (OEIP) is an on-demand electrophoretic drug delivery device, that via electronic to ionic signal conversion enables drug delivery without additional pressure or volume changes. The fundamental component of OEIPs is their polyelectrolyte membranes which are shaped into ionic channels that conduct and deliver ionic drugs, with high spatiotemporal resolution. The patterning of these membranes is essential in OEIP devices and is typically achieved using laborious microprocessing techniques. Here, the development of an inkjet printable formulation of polyelectrolyte is reported, based on a custom anionically functionalized hyperbranched polyglycerol (i-AHPG). This polyelectrolyte ink greatly simplifies the fabrication process and is used in the production of free-standing OEIPs on flexible polyimide (PI) substrates. Both i-AHPG and the OEIP devices are characterized, exhibiting favorable iontronic characteristics of charge selectivity and the ability to transport aromatic compounds. Further, the applicability of these technologies is demonstrated by the transport and delivery of the pharmaceutical compound bupivacaine to dorsal root ganglion cells with high spatial precision and effective nerve blocking, highlighting the applicability of these technologies for biomedical scenarios.


Assuntos
Eletrônica , Microtecnologia , Polieletrólitos , Sistemas de Liberação de Medicamentos , Íons/metabolismo , Bombas de Íon , Preparações Farmacêuticas
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