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1.
Alcohol Alcohol ; 59(4)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38953742

RESUMO

AIMS: Reward processing and regulation of emotions are thought to impact the development of addictive behaviors. In this study, we aimed to determine whether neural responses during reward anticipation, threat appraisal, emotion reactivity, and cognitive reappraisal predicted the transition from low-level to hazardous alcohol use over a 12-month period. METHODS: Seventy-eight individuals aged 18-22 with low-level alcohol use [i.e. Alcohol Use Disorder Identification Test (AUDIT) score <7] at baseline were enrolled. They completed reward-based and emotion regulation tasks during magnetic resonance imaging to examine reward anticipation, emotional reactivity, cognitive reappraisal, and threat anticipation (in the nucleus accumbens, amygdala, superior frontal gyrus, and insula, respectively). Participants completed self-report measures at 3-, 6-, 9-, and 12-month follow-up time points to determine if they transitioned to hazardous use (as defined by AUDIT scores ≥8). RESULTS: Of the 57 participants who completed follow-up, 14 (24.6%) transitioned to hazardous alcohol use. Higher baseline AUDIT scores were associated with greater odds of transitioning to hazardous use (odds ratio = 1.73, 95% confidence interval 1.13-2.66, P = .005). Brain activation to reward, threat, and emotion regulation was not associated with alcohol use. Of the neural variables, the amygdala response to negative imagery was numerically larger in young adults who transitioned to hazardous use (g = 0.31), but this effect was not significant. CONCLUSIONS: Baseline drinking levels were significantly associated with the transition to hazardous alcohol use. Studies with larger samples and longer follow-up should test whether the amygdala response to negative emotional imagery can be used to indicate a future transition to hazardous alcohol use.


Assuntos
Regulação Emocional , Imageamento por Ressonância Magnética , Recompensa , Humanos , Masculino , Feminino , Adulto Jovem , Regulação Emocional/fisiologia , Adolescente , Alcoolismo/psicologia , Alcoolismo/fisiopatologia , Alcoolismo/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Consumo de Bebidas Alcoólicas/psicologia , Consumo de Bebidas Alcoólicas/fisiopatologia , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Emoções/fisiologia , Adulto
2.
Microb Genom ; 10(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38625724

RESUMO

Streptomyces are prolific producers of secondary metabolites from which many clinically useful compounds have been derived. They inhabit diverse habitats but have rarely been reported in vertebrates. Here, we aim to determine to what extent the ecological source (bat host species and cave sites) influence the genomic and biosynthetic diversity of Streptomyces bacteria. We analysed draft genomes of 132 Streptomyces isolates sampled from 11 species of insectivorous bats from six cave sites in Arizona and New Mexico, USA. We delineated 55 species based on the genome-wide average nucleotide identity and core genome phylogenetic tree. Streptomyces isolates that colonize the same bat species or inhabit the same site exhibit greater overall genomic similarity than they do with Streptomyces from other bat species or sites. However, when considering biosynthetic gene clusters (BGCs) alone, BGC distribution is not structured by the ecological or geographical source of the Streptomyces that carry them. Each genome carried between 19-65 BGCs (median=42.5) and varied even among members of the same Streptomyces species. Nine major classes of BGCs were detected in ten of the 11 bat species and in all sites: terpene, non-ribosomal peptide synthetase, polyketide synthase, siderophore, RiPP-like, butyrolactone, lanthipeptide, ectoine, melanin. Finally, Streptomyces genomes carry multiple hybrid BGCs consisting of signature domains from two to seven distinct BGC classes. Taken together, our results bring critical insights to understanding Streptomyces-bat ecology and BGC diversity that may contribute to bat health and in augmenting current efforts in natural product discovery, especially from underexplored or overlooked environments.


Assuntos
Quirópteros , Animais , Filogenia , Genômica , Arizona , Bactérias
3.
Neuroimage Clin ; 42: 103571, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38471435

RESUMO

Despite the prevalence of Parkinson's disease (PD), there are no clinically-accepted neuroimaging biomarkers to predict the trajectory of motor or cognitive decline or differentiate Parkinson's disease from atypical progressive parkinsonian diseases. Since abnormal connectivity in the motor circuit and basal ganglia have been previously shown as early markers of neurodegeneration, we hypothesize that patterns of interregional connectivity could be useful to form patient-specific predictive models of disease state and of PD progression. We use fMRI data from subjects with Multiple System Atrophy (MSA), Progressive Supranuclear Palsy (PSP), idiopathic PD, and healthy controls to construct predictive models for motor and cognitive decline and differentiate between the four subgroups. Further, we identify the specific connections most informative for progression and diagnosis. When predicting the one-year progression in the MDS-UPDRS-III1* and Montreal Cognitive assessment (MoCA), we achieve new state-of-the-art mean absolute error performance. Additionally, the balanced accuracy we achieve in the diagnosis of PD, MSA, PSP, versus healthy controls surpasses that attained in most clinics, underscoring the relevance of the brain connectivity features. Our models reveal the connectivity between deep nuclei, motor regions, and the thalamus as the most important for prediction. Collectively these results demonstrate the potential of fMRI connectivity as a prognostic biomarker for PD and increase our understanding of this disease.


Assuntos
Imageamento por Ressonância Magnética , Doença de Parkinson , Paralisia Supranuclear Progressiva , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologia , Masculino , Feminino , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Idoso , Prognóstico , Paralisia Supranuclear Progressiva/fisiopatologia , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Progressão da Doença , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Atrofia de Múltiplos Sistemas/fisiopatologia , Estudos Longitudinais , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia
5.
Data Brief ; 53: 110197, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38406247

RESUMO

Trait reward sensitivity, risk for developing substance use, and mood disorders have each been linked with altered striatal responses to reward. Moreover, striatal response to reward is sensitive to social context, such as the presence of a peer, and drugs are often sought out and consumed in social contexts or as a result of social experiences. Thus, mood disorder symptoms, striatal responses to social context and social reward may play a role in substance use. To investigate this possibility, this dataset was collected as part of a National Institute on Drug Abuse (NIDA) grant titled "Aberrant Reward Sensitivity: Mechanisms Underlying Substance Use" (R03-DA046733). The overarching goal was to characterize the associations between neural responses to social and nonsocial rewards, trait reward sensitivity, substance use, and mood disorder symptoms. After obtaining questionnaire data quantifying reward sensitivity, substance use, and other psychosocial characteristics, young adults (N=59; 14 male, 45 female; mean age: 20.89 years ± 1.75 years) completed four fMRI tasks testing different features of social and reward processing. These included: 1) a strategic reward-based decision-making task with Ultimatum and Dictator Game conditions; 2) a task where participants shared rewards or losses with peers, strangers, or non-human partners; 3) a task in which participants received well-matched social and monetary rewards and punishment; and 4) a monetary incentive delay (MID) task in which participants tried to obtain or avoid rewards and losses of different magnitude. This dataset includes sociodemographic questionnaire data, anatomical, task-based fMRI, and corresponding behavioral task-based data. We outline several opportunities for extension and reuse, including exploration of individual differences, cross-task comparisons, and representational similarity analyses.

6.
Nat Mater ; 23(3): 429-438, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38361041

RESUMO

Cancer cell glycocalyx is a major line of defence against immune surveillance. However, how specific physical properties of the glycocalyx are regulated on a molecular level, contribute to immune evasion and may be overcome through immunoengineering must be resolved. Here we report how cancer-associated mucins and their glycosylation contribute to the nanoscale material thickness of the glycocalyx and consequently modulate the functional interactions with cytotoxic immune cells. Natural-killer-cell-mediated cytotoxicity is inversely correlated with the glycocalyx thickness of the target cells. Changes in glycocalyx thickness of approximately 10 nm can alter the susceptibility to immune cell attack. Enhanced stimulation of natural killer and T cells through equipment with chimeric antigen receptors can improve the cytotoxicity against mucin-bearing target cells. Alternatively, cytotoxicity can be enhanced through engineering effector cells to display glycocalyx-editing enzymes, including mucinases and sialidases. Together, our results motivate the development of immunoengineering strategies that overcome the glycocalyx armour of cancer cells.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Glicocálix/metabolismo , Mucinas/metabolismo , Antineoplásicos/metabolismo , Neoplasias/terapia
7.
J Neural Eng ; 20(6)2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-37963396

RESUMO

Objective.New measures of human brain connectivity are needed to address gaps in the existing measures and facilitate the study of brain function, cognitive capacity, and identify early markers of human disease. Traditional approaches to measure functional connectivity (FC) between pairs of brain regions in functional MRI, such as correlation and partial correlation, fail to capture nonlinear aspects in the regional associations. We propose a new machine learning based measure of FC (ML.FC) which efficiently captures linear and nonlinear aspects.Approach.To capture directed information flow between brain regions, effective connectivity (EC) metrics, including dynamic causal modeling and structural equation modeling have been used. However, these methods are impractical to compute across the many regions of the whole brain. Therefore, we propose two new EC measures. The first, a machine learning based measure of effective connectivity (ML.EC), measures nonlinear aspects across the entire brain. The second, Structurally Projected Granger Causality (SP.GC) adapts Granger Causal connectivity to efficiently characterize and regularize the whole brain EC connectome to respect underlying biological structural connectivity. The proposed measures are compared to traditional measures in terms ofreproducibilityand theability to predict individual traitsin order to demonstrate these measures' internal validity. We use four repeat scans of the same individuals from the Human Connectome Project and measure the ability of the measures to predict individual subject physiologic and cognitive traits.Main results.The proposed new FC measure ofML.FCattains high reproducibility (mean intra-subjectR2of 0.44), while the proposed EC measure ofSP.GCattains the highest predictive power (meanR2across prediction tasks of 0.66).Significance.The proposed methods are highly suitable for achieving high reproducibility and predictiveness and demonstrate their strong potential for future neuroimaging studies.


Assuntos
Encéfalo , Conectoma , Humanos , Reprodutibilidade dos Testes , Encéfalo/fisiologia , Conectoma/métodos , Imageamento por Ressonância Magnética/métodos , Aprendizado de Máquina
8.
Environ Sci Process Impacts ; 25(10): 1694-1707, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37728410

RESUMO

Dissolved organic matter (DOM) mediated indirect photodegradation can play an important role in the degradation of aquatic contaminants. Predicting the rate of this process requires knowledge of the photochemically produced reactive intermediates (PPRI) that react with the compound of interest, as well as the ability of individual DOM samples to produce PPRI. Key PPRI are typically identified using quencher studies, yet this approach often leads to results that are difficult to interpret. In this work, we analyze the indirect photodegradation of atorvastatin, carbamazepine, sulfadiazine, and benzotriazole using a diverse set of 48 waters from natural and engineered aquatic systems. We use this large data set to evaluate relationships between PPRI formation and indirect photodegradation rate constants, which are directly compared to results using standard quenching experiments. These data demonstrate that triplet state DOM (3DOM) and singlet oxygen (1O2) are critical PPRI for atorvastatin, carbamazepine, and sulfadiazine, while hydroxyl radical (˙OH) contributes to the indirect photodegradation of benzotriazole. We caution against relying on quenching studies because quenching of 3DOM limits the formation of 1O2 and all studied quenchers react with ˙OH. Furthermore, we show that DOM composition directly influences indirect photodegradation and that low molecular weight, microbial-like DOM is positively correlated with the indirect photodegradation rates of carbamazepine, sulfadiazine, and benzotriazole.


Assuntos
Poluentes Químicos da Água , Fotólise , Atorvastatina , Poluentes Químicos da Água/química , Sulfadiazina , Matéria Orgânica Dissolvida , Carbamazepina
9.
J Clin Oncol ; 41(24): 3965-3972, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37586209

RESUMO

PURPOSE: The Southwest Oncology Group (SWOG) coordinated an Intergroup study with the participation of Radiation Therapy Oncology Group (RTOG), and Eastern Cooperative Oncology Group (ECOG). This randomized phase III trial compared chemoradiotherapy versus radiotherapy alone in patients with nasopharyngeal cancers. MATERIALS AND METHODS: Radiotherapy was administered in both arms: 1.8- to 2.0-Gy/d fractions Monday to Friday for 35 to 39 fractions for a total dose of 70 Gy. The investigational arm received chemotherapy with cisplatin 100 mg/m2 on days 1, 22, and 43 during radiotherapy; postradiotherapy, chemotherapy with cisplatin 80 mg/m2 on day 1 and fluorouracil 1,000 mg/m2/d on days 1 to 4 was administered every 4 weeks for three courses. Patients were stratified by tumor stage, nodal stage, performance status, and histology. RESULTS: Of 193 patients registered, 147 (69 radiotherapy and 78 chemoradiotherapy) were eligible for primary analysis for survival and toxicity. The median progression-free survival (PFS) time was 15 months for eligible patients on the radiotherapy arm and was not reached for the chemo-radiotherapy group. The 3-year PFS rate was 24% versus 69%, respectively (P < .001). The median survival time was 34 months for the radiotherapy group and not reached for the chemo-radiotherapy group, and the 3-year survival rate was 47% versus 78%, respectively (P = .005). One hundred eighty-five patients were included in a secondary analysis for survival. The 3-year survival rate for patients randomized to radiotherapy was 46%, and for the chemoradiotherapy group was 76% (P < .001). CONCLUSION: We conclude that chemoradiotherapy is superior to radiotherapy alone for patients with advanced nasopharyngeal cancers with respect to PFS and overall survival.

10.
Front Immunol ; 14: 1187850, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37388744

RESUMO

Chimeric antigen receptor (CAR)-T cell therapy has emerged as a promising treatment option for several hematologic cancers. However, efforts to achieve the same level of therapeutic success in solid tumors have largely failed mainly due to CAR-T cell exhaustion and poor persistence at the tumor site. Although immunosuppression mediated by augmented programmed cell death protein-1 (PD-1) expression has been proposed to cause CAR-T cell hypofunction and limited clinical efficacy, little is known about the underlying mechanisms and immunological consequences of PD-1 expression on CAR-T cells. With flow cytometry analyses and in vitro and in vivo anti-cancer T cell function assays, we found that both manufactured murine and human CAR-T cell products displayed phenotypic signs of T cell exhaustion and heterogeneous expression levels of PD-1. Unexpectedly, PD-1high CAR-T cells outperformed PD-1low CAR-T cells in multiple T cell functions both in vitro and in vivo. Despite the achievement of superior persistence at the tumor site in vivo, adoptive transfer of PD-1high CAR-T cells alone failed to control tumor growth. Instead, a PD-1 blockade combination therapy significantly delayed tumor progression in mice infused with PD-1high CAR-T cells. Therefore, our data demonstrate that robust T cell activation during the ex vivo CAR-T cell manufacturing process generates a PD-1high CAR-T cell subset with improved persistence and enhanced anti-cancer functions. However, these cells may be vulnerable to the immunosuppressive microenvironment and require combination with PD-1 inhibition to maximize therapeutic functions in solid tumors.


Assuntos
Neoplasias Hematológicas , Neoplasias , Humanos , Animais , Camundongos , Receptor de Morte Celular Programada 1 , Neoplasias/terapia , Transferência Adotiva , Anticorpos , Microambiente Tumoral
11.
Nat Immunol ; 24(6): 1007-1019, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37069398

RESUMO

Adoptive transfer of genetically engineered chimeric antigen receptor (CAR) T cells is becoming a promising treatment option for hematological malignancies. However, T cell immunotherapies have mostly failed in individuals with solid tumors. Here, with a CRISPR-Cas9 pooled library, we performed an in vivo targeted loss-of-function screen and identified ST3 ß-galactoside α-2,3-sialyltransferase 1 (ST3GAL1) as a negative regulator of the cancer-specific migration of CAR T cells. Analysis of glycosylated proteins revealed that CD18 is a major effector of ST3GAL1 in activated CD8+ T cells. ST3GAL1-mediated glycosylation induces the spontaneous nonspecific tissue sequestration of T cells by altering lymphocyte function-associated antigen-1 (LFA-1) endocytic recycling. Engineered CAR T cells with enhanced expression of ßII-spectrin, a central LFA-1-associated cytoskeleton molecule, reversed ST3GAL1-mediated nonspecific T cell migration and reduced tumor growth in mice by improving tumor-specific homing of CAR T cells. These findings identify the ST3GAL1-ßII-spectrin axis as a major cell-intrinsic program for cancer-targeting CAR T cell migration and as a promising strategy for effective T cell immunotherapy.


Assuntos
Receptores de Antígenos Quiméricos , Animais , Camundongos , Linfócitos T CD8-Positivos , Linhagem Celular Tumoral , Movimento Celular , Imunoterapia Adotiva , Antígeno-1 Associado à Função Linfocitária , Espectrina , Humanos , Feminino
12.
J Biol Chem ; 299(5): 103003, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36775125

RESUMO

DNA gyrase is an essential nucleoprotein motor present in all bacteria and is a major target for antibiotic treatment of Mycobacterium tuberculosis (MTB) infection. Gyrase hydrolyzes ATP to add negative supercoils to DNA using a strand passage mechanism that has been investigated using biophysical and biochemical approaches. To analyze the dynamics of substeps leading to strand passage, single-molecule rotor bead tracking (RBT) has been used previously to follow real-time supercoiling and conformational transitions in Escherichia coli (EC) gyrase. However, RBT has not yet been applied to gyrase from other pathogenically relevant bacteria, and it is not known whether substeps are conserved across evolutionarily distant species. Here, we compare gyrase supercoiling dynamics between two evolutionarily distant bacterial species, MTB and EC. We used RBT to measure supercoiling rates, processivities, and the geometries and transition kinetics of conformational states of purified gyrase proteins in complex with DNA. Our results show that E. coli and MTB gyrases are both processive, with the MTB enzyme displaying velocities ∼5.5× slower than the EC enzyme. Compared with EC gyrase, MTB gyrase also more readily populates an intermediate state with DNA chirally wrapped around the enzyme, in both the presence and absence of ATP. Our substep measurements reveal common features in conformational states of EC and MTB gyrases interacting with DNA but also suggest differences in populations and transition rates that may reflect distinct cellular needs between these two species.


Assuntos
DNA Girase , Escherichia coli , Mycobacterium tuberculosis , Trifosfato de Adenosina/metabolismo , DNA , DNA Girase/química , DNA Girase/metabolismo , DNA Super-Helicoidal , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/metabolismo , Simulação de Dinâmica Molecular
13.
BJA Educ ; 23(2): 52-60, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36686887
14.
15.
Surg Endosc ; 37(2): 1449-1457, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35764842

RESUMO

BACKGROUND: Enhanced recovery protocols (ERPs) after metabolic and bariatric surgery (MBS) may help decrease length of stay (LOS) and postoperative nausea/vomiting but implementation is often fraught with challenges. The primary aim of this pilot study was to standardize a MBS ERP with a real-time data support dashboard and checklist and assess impact on global and individual element compliance. The secondary aim was to evaluate 30 day outcomes including LOS, hospital readmissions, and re-operations. METHODS AND PROCEDURES: An ERP, paper checklist, and virtual dashboard aligned on MBS patient care elements for pre-, intra-, and post-operative phases of care were developed and sequentially deployed. The dashboard includes surgical volumes, operative times, ERP compliance, and 30 day outcomes over a rolling 18 month period. Overall and individual element ERP compliance and outcomes were compared pre- and post-implementation via two-tailed Student's t-tests. RESULTS: Overall, 471 patients were identified (pre-implementation: 193; post-implementation: 278). Baseline monthly average compliance rates for all patient care elements were 1.7%, 3.7%, and 6.2% for pre-, intra-, and post-operative phases, respectively. Following ERP integration with dashboard and checklist, the intra-operative phase achieved the highest overall monthly average compliance at 31.3% (P < 0.01). Following the intervention, pre-operative acetaminophen administration had the highest monthly mean compliance at ≥ 99.1%. Overall TAP block use increased 3.2-fold from a baseline mean rate of 25.4-80.8% post-implementation (P < 0.01). A significant decrease in average intra-operative monthly morphine milligram equivalents use was noted with a 56% drop pre- vs. post-implementation. Average LOS decreased from 2.0 to 1.7 days post-implementation with no impact on post-operative outcomes. CONCLUSION: Implementation of a checklist and dashboard facilitated ERP integration and adoption of process measures with many improvements in compliance but no impact on 30 day outcomes. Further research is required to understand how clinical support tools can impact ERP adoption among MBS patients.


Assuntos
Cirurgia Bariátrica , Recuperação Pós-Cirúrgica Melhorada , Humanos , Projetos Piloto , Assistência Perioperatória/métodos , Tempo de Internação , Estudos Retrospectivos
16.
J Hosp Infect ; 131: 122-125, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36272553

RESUMO

BACKGROUND: N95 filtering facepiece respirators (FFRs) are essential personal protective equipment (PPE) for protecting healthcare workers from airborne pathogens. AIM: To perform the first large-scale evaluation of particulate filtration efficiency (PFE) of three models of N95 FFRs following clinical usage and vaporized hydrogen peroxide (VHP) decontamination. METHODS: Three variables were assessed for effect on PFE following VHP decontamination: VHP sterilizer model, N95 respirator model, and prior N95 clinical usage. FINDINGS: The VHP sterilizer model and N95 FFR model impacted PFE performance. Worn N95 FFRs had a 91% lower odds of exhibiting ≥95% PFE compared with the control. CONCLUSION: This work highlights the importance of validating any N95 FFR decontamination programme in its entirety, including prior clinical usage.


Assuntos
Respiradores N95 , Dispositivos de Proteção Respiratória , Humanos , Peróxido de Hidrogênio/farmacologia , Descontaminação , Filtração , Reutilização de Equipamento
17.
AJNR Am J Neuroradiol ; 43(10): 1508-1515, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36137658

RESUMO

BACKGROUND AND PURPOSE: Pediatric posterior fossa tumors often present with hydrocephalus; postoperatively, up to 25% of patients develop cerebellar mutism syndrome. Arterial spin-labeling is a noninvasive means of quantifying CBF and bolus arrival time. The aim of this study was to investigate how changes in perfusion metrics in children with posterior fossa tumors are modulated by cerebellar mutism syndrome and hydrocephalus requiring pre-resection CSF diversion. MATERIALS AND METHODS: Forty-four patients were prospectively scanned at 3 time points (preoperatively, postoperatively, and at 3-month follow-up) with single- and multi-inflow time arterial spin-labeling sequences. Regional analyses of CBF and bolus arrival time were conducted using coregistered anatomic parcellations. ANOVA and multivariable, linear mixed-effects modeling analysis approaches were used. The study was registered at clinicaltrials.gov (NCT03471026). RESULTS: CBF increased after tumor resection and at follow-up scanning (P = .045). Bolus arrival time decreased after tumor resection and at follow-up scanning (P = .018). Bolus arrival time was prolonged (P = .058) following the midline approach, compared with cerebellar hemispheric surgical approaches to posterior fossa tumors. Multivariable linear mixed-effects modeling showed that regional perfusion changes were more pronounced in the 6 children who presented with symptomatic obstructive hydrocephalus requiring pre-resection CSF diversion, with hydrocephalus lowering the baseline mean CBF by 20.5 (standard error, 6.27) mL/100g/min. Children diagnosed with cerebellar mutism syndrome (8/44, 18.2%) had significantly higher CBF at follow-up imaging than those who were not (P = .040), but no differences in pre- or postoperative perfusion parameters were seen. CONCLUSIONS: Multi-inflow time arterial spin-labeling shows promise as a noninvasive tool to evaluate cerebral perfusion in the setting of pediatric obstructive hydrocephalus and demonstrates increased CBF following resolution of cerebellar mutism syndrome.


Assuntos
Neoplasias Encefálicas , Hidrocefalia , Neoplasias Infratentoriais , Mutismo , Criança , Humanos , Neoplasias Encefálicas/patologia , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/cirurgia , Neoplasias Infratentoriais/diagnóstico por imagem , Neoplasias Infratentoriais/cirurgia , Perfusão , Complicações Pós-Operatórias , Marcadores de Spin , Estudos Prospectivos
18.
Nanotechnology ; 33(48)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-35940063

RESUMO

Devices based on arrays of interconnected magnetic nano-rings with emergent magnetization dynamics have recently been proposed for use in reservoir computing applications, but for them to be computationally useful it must be possible to optimise their dynamical responses. Here, we use a phenomenological model to demonstrate that such reservoirs can be optimised for classification tasks by tuning hyperparameters that control the scaling and input-rate of data into the system using rotating magnetic fields. We use task-independent metrics to assess the rings' computational capabilities at each set of these hyperparameters and show how these metrics correlate directly to performance in spoken and written digit recognition tasks. We then show that these metrics, and performance in tasks, can be further improved by expanding the reservoir's output to include multiple, concurrent measures of the ring arrays' magnetic states.

19.
Crit Care Explor ; 4(5): e0687, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35783549

RESUMO

Catecholamines and vasopressin are commonly used in patients with post cardiovascular surgery vasoplegia (PCSV). Multimodal therapy, including methylene blue (MB), hydroxocobalamin, and angiotensin II (Ang II), may improve outcomes in patients who remain hypotensive despite catecholamine and vasopressin therapy. However, a standardized approach has not been established. We created a protocol at Emory Healthcare (Emory Protocol), which provides guidance on norepinephrine equivalent dose (NED) and the use of noncatecholamines in the setting of PCSV and sought to determine the clinical significance of adherence to the protocol. DESIGN: Retrospective study. SETTING: Multisite study at Emory University Hospital. PATIENTS: Patients receiving Ang II for PCSV in any cardiovascular ICU from 2018 to 2020. INTERVENTIONS: Patient encounters were scored on Emory Protocol compliance based on NED (1-5), use of vasopressin (1-2), use of MB (1-2), and documentation of high-output shock (1-4). A compliant score was less than 7, moderately compliant 7 to 8, and poorly compliant greater than 8. Demographics, clinical data, and outcomes were abstracted from the medical records. MEASUREMENTS AND MAIN RESULTS: Of the 78 consecutive patients receiving Ang II for PCSV, overall ICU mortality was 26.9%, with an average compliance score of 6.2. ICU mortality was 21.1% for compliant cases (n = 38), 29.7% for moderately compliant cases (n = 24), and 37.5% for poorly compliant cases (n = 16). In regression analysis, the cumulative compliance score to the Emory Protocol was predictive of ICU mortality (p = 0.027). CONCLUSIONS: Compliance with the Emory Protocol, emphasizing early initiation of the noncatecholamines vasopressin, MB, hydroxocobalamin, and Ang II at lower catecholamine doses in high-output shock, is associated with improved ICU mortality.

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