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1.
BMC Med Educ ; 24(1): 657, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867188

RESUMO

BACKGROUND: Staff shortages limit access to health services. The bidirectional benefits of allied health clinical placements are understood in the domains of student learning, health service delivery, and future workforce development. Still, the benefits to current workforce outcomes remain unknown. This review provides insights into the effects of allied health student placements in acute and primary care settings, particularly on healthcare staff's knowledge and procedural skills. METHODS: This search was based on the integrative review process established by Whittemore and Knafl in 2005. In October 2023, the first author (MH) searched five major electronic databases: Medline-EBSCO, PubMed, CINAHL, Embase, and Scopus. The CLUSTER model was used to track additional references. The first three authors (MH, SM, and SC) were involved in screening, quality appraisal, and synthesis of the studies. Data were thematically synthesised and analysed. RESULTS: MeSH headings and keywords were used in key search areas: health education, health professional training, clinical placements, and allied health professions. The systematic search yielded 12 papers on allied health student placements across various healthcare settings in rural and metropolitan areas, with no high-quality methodologies measuring student placements' impact on staff knowledge and skills. Four main themes were identified from the analysis: meaningful student integration in service delivery, targeted educational support to healthcare staff, development of staff procedural skills and confidence, and the mechanisms of why student placements work in this aspect. CONCLUSIONS: This review suggests that offering allied health student placement could be a promising approach to supporting rural healthcare staff in performing patient assessments and treatments proficiently and collaboratively. However, this requires further investigation to confirm.


Assuntos
Pessoal Técnico de Saúde , Competência Clínica , Atenção Primária à Saúde , Humanos , Pessoal Técnico de Saúde/educação
2.
Nat Commun ; 15(1): 4271, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769289

RESUMO

T Cell Receptor (TCR) antigen binding underlies a key mechanism of the adaptive immune response yet the vast diversity of TCRs and the complexity of protein interactions limits our ability to build useful low dimensional representations of TCRs. To address the current limitations in TCR analysis we develop a capacity-controlled disentangling variational autoencoder trained using a dataset of approximately 100 million TCR sequences, that we name TCR-VALID. We design TCR-VALID such that the model representations are low-dimensional, continuous, disentangled, and sufficiently informative to provide high-quality TCR sequence de novo generation. We thoroughly quantify these properties of the representations, providing a framework for future protein representation learning in low dimensions. The continuity of TCR-VALID representations allows fast and accurate TCR clustering and is benchmarked against other state-of-the-art TCR clustering tools and pre-trained language models.


Assuntos
Receptores de Antígenos de Linfócitos T , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T/genética , Humanos , Aprendizado Profundo , Algoritmos , Análise por Conglomerados , Biologia Computacional/métodos , Sequência de Aminoácidos
3.
Transl Psychiatry ; 13(1): 371, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38040678

RESUMO

Activity changes within the anterior cingulate cortex (ACC) are implicated in the antidepressant effects of ketamine, but the ACC is cytoarchitectonically and functionally heterogeneous and ketamine's effects may be subregion specific. In the context of a double-blind randomized placebo-controlled crossover trial investigating the clinical and resting-state fMRI effects of intravenous ketamine vs. placebo in patients with treatment resistant depression (TRD) vs. healthy volunteers (HV), we used seed-based resting-state functional connectivity (rsFC) analyses to determine differential changes in subgenual ACC (sgACC), perigenual ACC (pgACC) and dorsal ACC (dACC) rsFC two days post-infusion. Across cingulate subregions, ketamine differentially modulated rsFC to the right insula and anterior ventromedial prefrontal cortex, compared to placebo, in TRD vs. HV; changes to pgACC-insula connectivity correlated with improvements in depression scores. Post-hoc analysis of each cingulate subregion separately revealed differential modulation of sgACC-hippocampal, sgACC-vmPFC, pgACC-posterior cingulate, and dACC-supramarginal gyrus connectivity. By comparing rsFC changes following ketamine vs. placebo in the TRD group alone, we found that sgACC rsFC was most substantially modulated by ketamine vs. placebo. Changes to sgACC-pgACC, sgACC-ventral striatal, and sgACC-dACC connectivity correlated with improvements in anhedonia symptoms. This preliminary evidence suggests that accurate segmentation of the ACC is needed to understand the precise effects of ketamine's antidepressant and anti-anhedonic action.


Assuntos
Ketamina , Humanos , Ketamina/farmacologia , Ketamina/uso terapêutico , Giro do Cíngulo , Córtex Pré-Frontal , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Imageamento por Ressonância Magnética
4.
Oxf Med Case Reports ; 2023(5): omad012, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37260728

RESUMO

Administration of the ChAdOx1 nCoV-19 (AstraZeneca) vaccination has recently been associated with rare, unusual cases of thrombotic events. We report a case of a 55-year-old woman who presented to hospital with headaches, petechial rashes and bruising-7 days after receiving her first vaccine dose. Blood tests showed low platelets, a markedly high d-dimer and positive anti-platelet factor 4 antibodies. Computed tomography (CT) of head and venogram showed features consistent with venous sinus thrombosis. She was immediately started on IV pooled immunoglobulin therapy, high-dose prednisolone and full anticoagulation. Subsequent magnetic resonance imaging of head and venogram supported the initial CT findings, with features suggestive of a small-volume venous sinus thrombosis. Additionally, CT pulmonary angiogram revealed a right-sided segmental pulmonary embolism. Our case highlights the importance of increased awareness of this complication after covid vaccination and how searching for distal thrombotic events and liaison with tertiary centres influence clinical outcomes.

5.
Sci Rep ; 13(1): 8452, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37231180

RESUMO

Identifying epitopes that T cells respond to is critical for understanding T cell-mediated immunity. Traditional multimer and other single cell assays often require large blood volumes and/or expensive HLA-specific reagents and provide limited phenotypic and functional information. Here, we present the Rapid TCR:Epitope Ranker (RAPTER) assay, a single cell RNA sequencing (scRNA-SEQ) method that uses primary human T cells and antigen presenting cells (APCs) to assess functional T cell reactivity. Using hash-tag oligonucleotide (HTO) coding and T cell activation-induced markers (AIM), RAPTER defines paired epitope specificity and TCR sequence and can include RNA- and protein-level T cell phenotype information. We demonstrate that RAPTER identified specific reactivities to viral and tumor antigens at sensitivities as low as 0.15% of total CD8+ T cells, and deconvoluted low-frequency circulating HPV16-specific T cell clones from a cervical cancer patient. The specificities of TCRs identified by RAPTER for MART1, EBV, and influenza epitopes were functionally confirmed in vitro. In summary, RAPTER identifies low-frequency T cell reactivities using primary cells from low blood volumes, and the resulting paired TCR:ligand information can directly enable immunogenic antigen selection from limited patient samples for vaccine epitope inclusion, antigen-specific TCR tracking, and TCR cloning for further therapeutic development.


Assuntos
Linfócitos T CD8-Positivos , Epitopos de Linfócito T , Humanos , Receptores de Antígenos de Linfócitos T/genética , Membrana Celular
7.
Lancet Haematol ; 9(10): e724-e732, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35988546

RESUMO

BACKGROUND: Mitapivat, an oral activator of pyruvate kinase (PK) in red blood cells (RBCs), has shown significant improvements in haemoglobin and haemolysis among patients with pyruvate kinase deficiency who were not receiving regular transfusions. We aimed to evaluate the efficacy and safety of mitapivat in adults with pyruvate kinase deficiency receiving regular transfusions. METHODS: ACTIVATE-T was an open-label, single-arm, phase 3 trial conducted in 20 centres across Europe, North America, and Asia. Eligible participants were adults (aged ≥18 years) with a clinical laboratory confirmation of pyruvate kinase deficiency receiving regular transfusions (at least six episodes in the previous year). Participants received oral mitapivat during a 16-week dose-optimisation period (5 mg, 20 mg, 50 mg twice daily) and 24-week fixed-dose period. The primary endpoint was a reduction in transfusion burden (≥33% reduction in number of RBC units transfused during the fixed-dose period, compared with the participant's individual historical transfusion burden, standardised to 24 weeks). Efficacy and safety were assessed in all participants who received at least one dose of mitapivat. This trial is registered with ClinicalTrials.gov, NCT03559699, and is complete. FINDINGS: Between June 26, 2018, and Feb 4, 2020, 27 participants (20 [74%] female and seven [26%] male; 20 [74%] White, three [11%] Asian, and four [15%] not reported) were enrolled and received at least one dose of mitapivat. Median duration of exposure to mitapivat was 40·3 weeks (IQR 40·0-41·3). A reduction in transfusion burden by at least 33% was found in ten (37%) participants (95% CI 19-58; p=0·0002). The most common treatment-emergent adverse events were increase in alanine aminotransferase (ten [37%] participants), headache (ten [37%]), increase in aspartate aminotransferase (five [19%]), fatigue (five [19%]), and nausea (five [19%]). Two grade 3 treatment-emergent adverse events were related to study treatment: joint swelling (one participant [4%]) and an increase in aspartate aminotransferase (one participant [4%]). Three participants had serious treatment-emergent adverse events, none related to the study treatment: increased blood triglycerides, ovarian cyst, and renal colic (each in one participant [4%]). No treatment-related deaths were observed. INTERPRETATION: Mitapivat represents a novel therapy that can reduce transfusion burden in some adults with pyruvate kinase deficiency receiving regular transfusions, and is the first disease-modifying agent approved in this disease. FUNDING: Agios Pharmaceuticals.


Assuntos
Hemoglobinas , Piruvato Quinase , Adolescente , Adulto , Alanina Transaminase , Anemia Hemolítica Congênita não Esferocítica , Aspartato Aminotransferases , Feminino , Humanos , Masculino , Preparações Farmacêuticas , Piperazinas , Piruvato Quinase/deficiência , Erros Inatos do Metabolismo dos Piruvatos , Quinolinas , Resultado do Tratamento , Triglicerídeos
8.
Blood ; 140(19): 2053-2062, 2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-35576529

RESUMO

Polymerization of deoxygenated hemoglobin S underlies the pathophysiology of sickle cell disease (SCD). In activating red blood cell pyruvate kinase and glycolysis, mitapivat (AG-348) increases adenosine triphosphate (ATP) levels and decreases the 2,3-diphosphoglycerate (2,3-DPG) concentration, an upstream precursor in glycolysis. Both changes have therapeutic potential for patients with SCD. Here, we evaluated the safety and tolerability of multiple ascending doses of mitapivat in adults with SCD with no recent blood transfusions or changes in hydroxyurea or l-glutamine therapy. Seventeen subjects were enrolled; 1 subject was withdrawn shortly after starting the study. Sixteen subjects completed 3 ascending dose levels of mitapivat (5, 20, and 50 mg, twice daily [BID]) for 2 weeks each; following a protocol amendment, the dose was escalated to 100 mg BID in 9 subjects. Mitapivat was well tolerated at all dose levels, with the most common treatment-emergent adverse events (AEs) being insomnia, headache, and hypertension. Six serious AEs (SAEs) included 4 vaso-occlusive crises (VOCs), non-VOC-related shoulder pain, and a preexisting pulmonary embolism. Two VOCs occurred during drug taper and were possibly drug related; no other SAEs were drug related. Mean hemoglobin increase at the 50 mg BID dose level was 1.2 g/dL, with 9 of 16 (56.3%) patients achieving a hemoglobin response of a ≥1 g/dL increase compared with baseline. Mean reductions in hemolytic markers and dose-dependent decreases in 2,3-DPG and increases in ATP were also observed. This study provides proof of concept that mitapivat has disease-modifying potential in patients with SCD. This trial was registered at www.clinicaltrials.gov as #NCT04000165.


Assuntos
Anemia Falciforme , Piruvato Quinase , Adulto , Humanos , Ácido Pirúvico , 2,3-Difosfoglicerato , Anemia Falciforme/tratamento farmacológico , Hemoglobinas , Trifosfato de Adenosina
9.
N Engl J Med ; 386(15): 1432-1442, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35417638

RESUMO

BACKGROUND: Pyruvate kinase deficiency is a rare, hereditary, chronic condition that is associated with hemolytic anemia. In a phase 2 study, mitapivat, an oral, first-in-class activator of erythrocyte pyruvate kinase, increased the hemoglobin level in patients with pyruvate kinase deficiency. METHODS: In this global, phase 3, randomized, placebo-controlled trial, we evaluated the efficacy and safety of mitapivat in adults with pyruvate kinase deficiency who were not receiving regular red-cell transfusions. The patients were assigned to receive either mitapivat (5 mg twice daily, with potential escalation to 20 or 50 mg twice daily) or placebo for 24 weeks. The primary end point was a hemoglobin response (an increase from baseline of ≥1.5 g per deciliter in the hemoglobin level) that was sustained at two or more scheduled assessments at weeks 16, 20, and 24. Secondary efficacy end points were the average change from baseline in the hemoglobin level, markers of hemolysis and hematopoiesis, and the change from baseline at week 24 in two pyruvate kinase deficiency-specific patient-reported outcome measures. RESULTS: Sixteen of the 40 patients (40%) in the mitapivat group had a hemoglobin response, as compared with none of the 40 patients in the placebo group (adjusted difference, 39.3 percentage points; 95% confidence interval, 24.1 to 54.6; two-sided P<0.001). Patients who received mitapivat had a greater response than those who received placebo with respect to each secondary end point, including the average change from baseline in the hemoglobin level. The most common adverse events were nausea (in 7 patients [18%] in the mitapivat group and 9 patients [23%] in the placebo group) and headache (in 6 patients [15%] and 13 patients [33%], respectively). Adverse events of grade 3 or higher occurred in 10 patients (25%) who received mitapivat and 5 patients (13%) who received placebo. CONCLUSIONS: In patients with pyruvate kinase deficiency, mitapivat significantly increased the hemoglobin level, decreased hemolysis, and improved patient-reported outcomes. No new safety signals were identified in the patients who received mitapivat. (Funded by Agios Pharmaceuticals; ACTIVATE ClinicalTrials.gov number, NCT03548220.).


Assuntos
Piperazinas , Piruvato Quinase , Quinolinas , Adulto , Anemia Hemolítica Congênita não Esferocítica/tratamento farmacológico , Método Duplo-Cego , Hemoglobinas/análise , Hemoglobinas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Piruvato Quinase/deficiência , Erros Inatos do Metabolismo dos Piruvatos/tratamento farmacológico , Quinolinas/farmacologia , Quinolinas/uso terapêutico
10.
Clin Transl Radiat Oncol ; 33: 30-36, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35024462

RESUMO

BACKGROUND AND PURPOSE: Bioselection with induction chemotherapy in larynx cancer is associated with excellent larynx preservation and disease-specific survival but requires visual inspection of the primary tumor. We retrospectively compare clinical and imaging response in bioselected patients to develop predictive models of surgeon-assessed response (SR), laryngectomy-free survival (LFS), and overall survival (OS) in bioselected patients. MATERIALS AND METHODS: In a secondary analysis of patients on two single-institution bioselection trials, model building used a regularized regression model (elastic-net) and applied nested cross-validation. Logistic regression-based model was used to predict SR and Cox proportional hazard-based models were used to predict LFS and OS. RESULTS: In 115 patients with a median age of 57 years, most patients had supraglottic tumors (73.0%) and T3/T4 disease (94.8%). Definitive treatment was chemoradiation in 76.5% and laryngectomy in 23.5%. Change in primary tumor (OR = 5.78, p < 0.001) and N-classification (OR = 1.64, p = 0.003) predicted SR (AUC 0.847). Change in tumor volume (HR = 0.58, p < 0.001) predicted LFS (c-index 0.724). N-classification (HR = 1.48, p = 0.04) and pre-chemotherapy tumor volume (HR = 1.30, p = 0.174) predicted OS (c-index 0.552). CONCLUSIONS: Imaging offers a non-invasive opportunity to evaluate response to induction chemotherapy, complementary to surgeon assessment. Further evaluation of approaches to bioselection that optimize generalizability of this paradigm are needed, and clinical trials utilizing imaging to predict outcomes including LFS are warranted.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34126264

RESUMO

BACKGROUND: Ketamine as an antidepressant improves anhedonia as early as 2 hours after infusion. These drug effects are thought to be exerted via actions on reward-related brain areas-yet these actions remain largely unknown. Our study investigates ketamine's effects during the anticipation and receipt of an expected reward, after the psychotomimetic effects of ketamine have passed, when early antidepressant effects are reported. METHODS: We examined ketamine's effects during the anticipation and receipt of expected rewards on predefined brain areas, namely, the dorsal and ventral striatum, ventral tegmental area, amygdala, and insula. We recruited 37 male and female participants with remitted depression who were free from symptoms and antidepressant treatments at the time of the scan. Participants were scanned 2 hours after drug administration in a double-blind crossover design (ketamine: 0.5 mg/kg and placebo) while performing a monetary reward task. RESULTS: A significant main effect of ketamine was observed across all regions of interest during the anticipation and feedback phases of win and no-win trials. The drug effects were particularly prominent in the nucleus accumbens and putamen, which showed increased activation on the receipt of smaller rewards compared with neutral. The levels of (2R,6R)-hydroxynorketamine 2 hours after infusion significantly correlated with the activation observed in the ventral tegmental area for that contrast. CONCLUSIONS: These findings demonstrate that ketamine can produce detectable changes in reward-related brain areas 2 hours after infusion, which occur without symptom changes and support the idea that ketamine might improve reward-related symptoms via modulation of response to feedback.


Assuntos
Ketamina , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Encéfalo , Estudos Cross-Over , Depressão/tratamento farmacológico , Método Duplo-Cego , Feminino , Humanos , Masculino , Recompensa
12.
Sci Adv ; 7(20)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33990328

RESUMO

T cell receptor (TCR) antigen-specific recognition is essential for the adaptive immune system. However, building a TCR-antigen interaction map has been challenging due to the staggering diversity of TCRs and antigens. Accordingly, highly multiplexed dextramer-TCR binding assays have been recently developed, but the utility of the ensuing large datasets is limited by the lack of robust computational methods for normalization and interpretation. Here, we present a computational framework comprising a novel method, ICON (Integrative COntext-specific Normalization), for identifying reliable TCR-pMHC (peptide-major histocompatibility complex) interactions and a neural network-based classifier TCRAI that outperforms other state-of-the-art methods for TCR-antigen specificity prediction. We further demonstrated that by combining ICON and TCRAI, we are able to discover novel subgroups of TCRs that bind to a given pMHC via different mechanisms. Our framework facilitates the identification and understanding of TCR-antigen-specific interactions for basic immunological research and clinical immune monitoring.


Assuntos
Complexo Principal de Histocompatibilidade , Receptores de Antígenos de Linfócitos T , Antígenos , Antígenos de Histocompatibilidade/metabolismo , Ligação Proteica , Receptores de Antígenos de Linfócitos T/metabolismo , Especificidade do Receptor de Antígeno de Linfócitos T
13.
J Psychopharmacol ; 35(9): 1099-1110, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33908296

RESUMO

BACKGROUND: Cognitive flexibility deficits are present in patients with schizophrenia and are strong predictors of functional outcome but, as yet, have no pharmacological treatments. AIMS: The purpose of this study was to investigate whether the phosphodiesterase type-4 inhibitor, roflumilast, can improve cognitive flexibility performance and functional brain activity in patients with schizophrenia. METHODS: This was a within-subject, randomised, double-blind, placebo-controlled, three-period crossover study using a version of the Intradimensional/Extradimensional (ID/ED) task, optimised for functional magnetic resonance imaging (fMRI), in 10 patients with schizophrenia who were scanned after receiving placebo, 100 µg or 250 µg roflumilast for 8 consecutive days. Data from an additional fMRI ID/ED study of 18 healthy participants on placebo was included to contextualise the schizophrenia-related performance and activations. The fMRI analyses included a priori driven region of interest (ROI) analysis of the dorsal frontoparietal attention network. RESULTS: Patients on placebo demonstrated broad deficits in task performance compared to the healthy comparison group, accompanied by preserved network activity for solution search, but reduced activity in left ventrolateral prefrontal cortex (VLPFC) and posterior parietal cortex for attentional set-shifting and reduced activity in left dorsolateral prefrontal cortex (DLPFC) for reversal learning. These ROI deficits were ameliorated by 250 µg roflumilast, whereas during solution search 100 µg roflumilast reduced activity in the left orbitofrontal cortex, right DLPFC and bilateral PPC, which was associated with an improvement in formation of attentional sets. CONCLUSIONS: The results suggest roflumilast has dose-dependent cognitive enhancing effects on the ID/ED task in patients with schizophrenia, and provides sufficient support for larger studies to test roflumilast's role in improving cognitive flexibility deficits in this clinical population.


Assuntos
Aminopiridinas/farmacologia , Benzamidas/farmacologia , Disfunção Cognitiva/tratamento farmacológico , Inibidores da Fosfodiesterase 4/farmacologia , Esquizofrenia/tratamento farmacológico , Adulto , Idoso , Aminopiridinas/administração & dosagem , Benzamidas/administração & dosagem , Disfunção Cognitiva/fisiopatologia , Estudos Cross-Over , Ciclopropanos/administração & dosagem , Ciclopropanos/farmacologia , Córtex Pré-Frontal Dorsolateral/diagnóstico por imagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Inibidores da Fosfodiesterase 4/administração & dosagem , Córtex Pré-Frontal/diagnóstico por imagem , Esquizofrenia/fisiopatologia
14.
Hum Brain Mapp ; 42(9): 2766-2777, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33666305

RESUMO

Dopamine (DA) mediated brain activity is intimately linked to reward-driven cerebral responses, while aberrant reward processing has been implicated in several psychiatric disorders. fMRI has been a valuable tool in understanding the mechanism by which DA modulators alter reward-driven responses and how they may exert their therapeutic effect. However, the potential effects of a pharmacological compound on aspects of neurovascular coupling may cloud the interpretability of the BOLD contrast. Here, we assess the effects of risperidone on reward driven BOLD signals produced by reward anticipation and outcome, while attempting to control for potential drug effects on regional cerebral blood flow (CBF) and cerebrovascular reactivity (CVR). Healthy male volunteers (n = 21) each received a single oral dose of either 0.5 mg, 2 mg of risperidone or placebo in a double-blind, placebo-controlled, randomised, three-period cross-over study design. Participants underwent fMRI scanning while performing the widely used Monetary Incentive Delay (MID) task to assess drug impact on reward function. Measures of CBF (Arterial Spin Labelling) and breath-hold challenge induced BOLD signal changes (as a proxy for CVR) were also acquired and included as covariates. Risperidone produced divergent, dose-dependent effects on separate phases of reward processing, even after controlling for potential nonneuronal influences on the BOLD signal. These data suggest the D2 antagonist risperidone has a wide-ranging influence on DA-mediated reward function independent of nonneuronal factors. We also illustrate that assessment of potential vascular confounds on the BOLD signal may be advantageous when investigating CNS drug action and advocate for the inclusion of these additional measures into future study designs.


Assuntos
Antecipação Psicológica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Suspensão da Respiração , Circulação Cerebrovascular/efeitos dos fármacos , Antagonistas dos Receptores de Dopamina D2/farmacologia , Neuroimagem Funcional , Desempenho Psicomotor/efeitos dos fármacos , Recompensa , Risperidona/farmacologia , Adulto , Encéfalo/diagnóstico por imagem , Estudos Cross-Over , Antagonistas dos Receptores de Dopamina D2/administração & dosagem , Método Duplo-Cego , Humanos , Imageamento por Ressonância Magnética , Masculino , Risperidona/administração & dosagem , Adulto Jovem
15.
Sci Rep ; 11(1): 2485, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510363

RESUMO

We present a new methodology for measuring few-femtosecond electronic and nuclear dynamics in both atoms and polyatomic molecules using multidimensional high harmonic generation (HHG) spectroscopy measurements, in which the spectra are recorded as a function of the laser intensity to form a two-dimensional data set. The method is applied to xenon atoms and to benzene molecules, the latter exhibiting significant fast nuclear dynamics following ionization. We uncover the signature of the sub-cycle evolution of the returning electron flux in strong-field ionized xenon atoms, implicit in the strong field approximation but not previously observed directly. We furthermore extract the nuclear autocorrelation function in strong field ionized benzene cations, which is determined to have a decay of [Formula: see text] fs, in good agreement with the [Formula: see text] fs obtained from direct dynamics variational multi-configuration Gaussian calculations. Our method requires minimal assumptions about the system, and is applicable even to un-aligned polyatomic molecules.

16.
Int J Radiat Oncol Biol Phys ; 110(2): 566-573, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33346093

RESUMO

PURPOSE: Predicting individual patient sensitivity to radiation therapy (RT) for tumor control or normal tissue toxicity is necessary to individualize treatment planning. In head and neck cancer, radiation doses are limited by many nearby critical structures, including structures involved in swallowing. Previous efforts showed that imaging parameters correlate with RT dose; here, we investigate the role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) blood volume (BV) changes in predicting dysphagia. METHODS AND MATERIALS: This study included 32 patients with locally advanced oropharyngeal squamous cell carcinoma treated with definitive chemoradiation on an institutional protocol incorporating baseline and early midtreatment DCE-MRI. BV maps of the pharyngeal constrictor muscles (PCM) were created, and BV increases midtreatment were correlated with the following parameters at 3 and 12 months post-RT: RT dose, Dynamic Imaging Grade of Swallowing Toxicity swallow score, aspiration frequency, European Organisation for Research and Treatment of Cancer HN35 patient-reported outcomes, physician-reported dysphagia, and feeding tube (FT) dependence. RESULTS: The mean BV to the PCMs increased from baseline to fraction 10, which was significant for the superior PCM (P = .006) and middle PCM (P < .001), with a trend in the inferior PCM where lower mean doses were seen (P = .077). The factors associated with FT dependence at 3 months included BV increases in the total PCM (correlation, 0.48; P = .006) and middle PCM (correlation, 0.50; P = .004). A post-RT increase in aspiration was associated with a BV increase in the superior PCM (correlation, 0.44; P = .013),and the increase in the total PCMs was marginally significant (correlation, 0.34; P = .06). The best-performing models of FT dependence (area under the receiver operating curve [AUC] = 0.84) and aspiration increases (AUC = 0.78) included BV increases as well as a mean RT dose to middle PCM. CONCLUSIONS: Our results suggest that midtreatment BV increases derived from DCE-MRI are an early predictor of dysphagia. Further investigation of these promising imaging markers to assess individual patient sensitivity to treatment and the patient's subsequent risk of toxicities is warranted to improve personalization of RT planning.


Assuntos
Volume Sanguíneo/fisiologia , Transtornos de Deglutição/fisiopatologia , Imageamento por Ressonância Magnética , Músculos Faríngeos/irrigação sanguínea , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Quimiorradioterapia/métodos , Meios de Contraste , Deglutição/efeitos da radiação , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Nutrição Enteral/instrumentação , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Aumento da Imagem/métodos , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/terapia , Músculos Faríngeos/diagnóstico por imagem , Estudos Prospectivos , Lesões por Radiação/complicações , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Fatores de Tempo
17.
Hum Brain Mapp ; 42(3): 555-566, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33079453

RESUMO

Recent studies have shown that drug-induced spatial alteration patterns in resting state functional activity as measured using magnetic resonance imaging (rsfMRI) are associated with the distribution of specific receptor systems targeted by respective compounds. Based on this approach, we introduce a toolbox (JuSpace) allowing for cross-modal correlation of MRI-based measures with nuclear imaging derived estimates covering various neurotransmitter systems including dopaminergic, serotonergic, noradrenergic, and GABAergic (gamma-aminobutric acid) neurotransmission. We apply JuSpace to two datasets covering Parkinson's disease patients (PD) and risperidone-induced changes in rsfMRI and cerebral blood flow (CBF). Consistently with the predominant neurodegeneration of dopaminergic and serotonergic system in PD, we find significant spatial associations between rsfMRI activity alterations in PD and dopaminergic (D2) and serotonergic systems (5-HT1b). Risperidone induced CBF alterations were correlated with its main targets in serotonergic and dopaminergic systems. JuSpace provides a biologically meaningful framework for linking neuroimaging to underlying neurotransmitter information.


Assuntos
Imageamento por Ressonância Magnética , Neuroimagem/métodos , Neurotransmissores/farmacologia , Tomografia por Emissão de Pósitrons , Receptores de Neurotransmissores , Transmissão Sináptica , Tomografia Computadorizada de Emissão de Fóton Único , Circulação Cerebrovascular/efeitos dos fármacos , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Receptores de Neurotransmissores/efeitos dos fármacos , Transmissão Sináptica/fisiologia
18.
Oral Oncol ; 111: 104853, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32805634

RESUMO

OBJECTIVES: Improved prognosis for p16+ oropharyngeal squamous cell carcinoma (OPSCC) has led to efforts to mitigate long-term complications of treatment, which remains poorly defined in late survivors. Here we characterize very late dysphagia in OPSCC. MATERIALS AND METHODS: Long-term review of 93 p16+ OPSCC patients treated with chemoradiation was performed. We scored videofluoroscopic swallow studies (VFSS) according to the Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scale. Very late dysphagia was defined >2.5 years from end of treatment. Fine-Gray regression models were used to assess dysphagia with competing risk of death. RESULTS: Median follow up was 10.5 years. 402 total VFSS were assessed (median 4 per patient, range 0-8). 15.1% of patients had a DIGEST score ≥2 very late after treatment. Very late DIGEST score ≥2 correlated with T-stage (HR 1.7, p = 0.049), second cancer (HR 6.5, p = 0.004), superior pharyngeal constrictor dose (HR 1.11, p = 0.050), total tongue dose (HR 1.07, p = 0.045), but not hypoglossal nerve dose (p > 0.2). Seven patients (7.5%) had late progressive dysphagia, defined as DIGEST score that increased by ≥2 beyond one year after treatment, and this correlated with higher ipsilateral hypoglossal nerve D1cc dose (75 vs 72 Gy, p = 0.037). CONCLUSION: In p16+ OPSCC patients treated with definitive chemoradiation, at least 7.5% developed late progressive dysphagia, and 15.1% experienced moderate dysphagia >2.5 years from treatment. Our study suggests that dose to tongue musculature may be associated with very late dysphagia, and hypoglossal nerve dose may be associated with late progressive dysphagia. More intensive long-term dysphagia survivorship monitoring is suggested.


Assuntos
Quimiorradioterapia/efeitos adversos , Transtornos de Deglutição/etiologia , Neoplasias Orofaríngeas/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Adulto , Idoso , Deglutição , Transtornos de Deglutição/diagnóstico por imagem , Feminino , Fluoroscopia/métodos , Seguimentos , Humanos , Nervo Hipoglosso/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Órgãos em Risco/efeitos da radiação , Neoplasias Orofaríngeas/mortalidade , Neoplasias Orofaríngeas/patologia , Músculos Faríngeos/efeitos da radiação , Doses de Radiação , Lesões por Radiação/complicações , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Fatores de Tempo , Língua/efeitos da radiação , Neoplasias da Língua/terapia
19.
Front Oncol ; 9: 1118, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31799173

RESUMO

Purpose: FDG-PET adds to clinical factors, such tumor stage and p16 status, in predicting local (LF), regional (RF), and distant failure (DF) in poor prognosis locally advanced head and neck cancer (HNC) treated with chemoradiation. We hypothesized that MRI-based quantitative imaging (QI) metrics could add to clinical predictors of treatment failure more significantly than FDG-PET metrics. Materials and methods: Fifty four patients with poor prognosis HNCs who were enrolled in an IRB approved prospective adaptive chemoradiotherapy trial were analyzed. MRI-derived gross tumor volume (GTV), blood volume (BV), and apparent diffusion coefficient (ADC) pre-treatment and mid-treatment (fraction 10), as well as pre-treatment FDG PET metrics, were analyzed in primary and individual nodal tumors. Cox proportional hazards models for prediction of LRF and DF free survival were used to test the additional value of QI metrics over dominant clinical predictors. Results: The mean ADC pre-RT and its change rate mid-treatment were significantly higher and lower in p16- than p16+ primary tumors, respectively. A Cox model identified that high mean ADC pre-RT had a high hazard for LF and RF in p16- but not p16+ tumors (p = 0.015). Most interesting, persisting subvolumes of low BV (TVbv) in primary and nodal tumors mid-treatment had high-risk for DF (p < 0.05). Also, total nodal GTV mid-treatment, mean/max SUV of FDG in all nodal tumors, and total nodal TLG were predictive for DF (p < 0.05). When including clinical stage (T4/N3) and total nodal GTV in the model, all nodal PET parameters had a p-value of >0.3, and only TVbv of primary tumors had a p-value of 0.06. Conclusion: MRI-defined biomarkers, especially persisting subvolumes of low BV, add predictive value to clinical variables and compare favorably with FDG-PET imaging markers. MRI could be well-integrated into the radiation therapy workflow for treatment planning, response assessment, and adaptive therapy.

20.
N Engl J Med ; 381(10): 933-944, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31483964

RESUMO

BACKGROUND: Pyruvate kinase deficiency is caused by mutations in PKLR and leads to congenital hemolytic anemia. Mitapivat is an oral, small-molecule allosteric activator of pyruvate kinase in red cells. METHODS: In this uncontrolled, phase 2 study, we evaluated the safety and efficacy of mitapivat in 52 adults with pyruvate kinase deficiency who were not receiving red-cell transfusions. The patients were randomly assigned to receive either 50 mg or 300 mg of mitapivat twice daily for a 24-week core period; eligible patients could continue treatment in an ongoing extension phase. RESULTS: Common adverse events, including headache and insomnia, occurred at the time of drug initiation and were transient; 92% of the episodes of headache and 47% of the episodes of insomnia resolved within 7 days. The most common serious adverse events, hemolytic anemia and pharyngitis, each occurred in 2 patients (4%). A total of 26 patients (50%) had an increase of more than 1.0 g per deciliter in the hemoglobin level. Among these patients, the mean maximum increase was 3.4 g per deciliter (range, 1.1 to 5.8), and the median time until the first increase of more than 1.0 g per deciliter was 10 days (range, 7 to 187); 20 patients (77%) had an increase of more than 1.0 g per deciliter in the hemoglobin level at more than 50% of visits during the core study period, with improvement in markers of hemolysis. The response was sustained in all 19 patients remaining in the extension phase, with a median follow-up of 29 months (range, 22 to 35). Hemoglobin responses were observed only in patients who had at least one missense PKLR mutation and were associated with the red-cell pyruvate kinase protein level at baseline. CONCLUSIONS: The administration of mitapivat was associated with a rapid increase in the hemoglobin level in 50% of adults with pyruvate kinase deficiency, with a sustained response during a median follow-up of 29 months during the extension phase. Adverse effects were mainly low-grade and transient. (Funded by Agios Pharmaceuticals; ClinicalTrials.gov number, NCT02476916.).


Assuntos
Anemia Hemolítica Congênita não Esferocítica/tratamento farmacológico , Hemoglobinas/metabolismo , Piperazinas/administração & dosagem , Piruvato Quinase/deficiência , Erros Inatos do Metabolismo dos Piruvatos/tratamento farmacológico , Quinolinas/administração & dosagem , Administração Oral , Adolescente , Adulto , Anemia Hemolítica Congênita não Esferocítica/sangue , Anemia Hemolítica Congênita não Esferocítica/genética , Catecóis , Esquema de Medicação , Feminino , Seguimentos , Cefaleia/induzido quimicamente , Humanos , Masculino , Mutação , Piperazinas/efeitos adversos , Piruvato Quinase/sangue , Piruvato Quinase/genética , Erros Inatos do Metabolismo dos Piruvatos/sangue , Erros Inatos do Metabolismo dos Piruvatos/genética , Quinolinas/efeitos adversos , Distúrbios do Início e da Manutenção do Sono/induzido quimicamente , Tirfostinas , Adulto Jovem
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