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Paediatric acute myeloid leukemia (AML) is a heterogeneous hematological malignancy still heavily reliant on traditional chemotherapeutic approaches. Combination treatments have shown to be a superior approach, but their success is often hindered by side effects and different drugs' pharmacokinetics. Here, we investigated ABT-737 and Purvalanol A as a potential drug pairing for pediatric AML and described the development of CD33-targeted polymeric nanoparticles (NPs) to enable their simultaneous targeted codelivery. Separate drug encapsulation within poly(lactic-co-glycolic acid) (PLGA) NPs was optimized prior to coencapsulation of both drugs at a synergistic ratio in PEGylated PLGA NPs. The therapeutic effects of formulations were evaluated in a panel of pediatric AML cells, and dual drug-loaded NPs (dual NPs) demonstrated significantly enhanced apoptotic cell death. Moreover, conjugation to gemtuzumab resulted in improved NP binding and internalization in CD33-positive cells. Finally, CD33-targeted dual-loaded NPs showed enhanced cytotoxicity to CD33-positive AML cells via CD33-mediated targeted drug delivery.
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Bacteria can evade antimicrobial therapy by hiding inside host cells such as macrophages. Here we examine the ability of PLGA nanoparticles to deliver antibiotics to intracellular bacteria, specifically focusing upon the impact of nanoparticle size. Different sized Rhodamine-B conjugated PLGA nanoparticles were synthesized and uptake examined in two macrophage cell lines, as well as different epithelial cells, to determine the optimal properties for macrophage uptake. These studies demonstrate macrophages display a consistent increase in uptake with increased PLGA nanoparticle diameter. In a bacteria-macrophage co-culture model, we then examined the efficacy of different sized antibiotic-loaded PLGA nanoparticles against intracellular infections with K. pneumoniae and S. aureus. Increasing the size of antibiotic-loaded PLGA nanoparticles significantly increased their potency against intracellular K. pneumoniae. However, this was not observed for S. aureus, potentially due to the observation these nanoparticles failed to access the compartment in which S. aureus reside. This work demonstrates for the first time that increasing the size of antibiotic-loaded PLGA nanoparticles can significantly enhance antimicrobial efficacy against K. pneumoniae intracellular macrophage infections. However, our S. aureus studies indicate this is not a 'one size fits all' approach for all intracellular infections.
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There has been a long debate about the possibility of multiple contemporaneous species of Australopithecus in both eastern and southern Africa, potentially exhibiting different forms of bipedal locomotion. Here, we describe the previously unreported morphology of the os coxae in the 3.67 Ma Australopithecus prometheus StW 573 from Sterkfontein Member 2, comparing it with variation in ossa coxae in living humans and apes as well as other Plio-Pleistocene hominins. Statistical comparisons indicate that StW 573 and 431 resemble humans in their anteroposteriorly great iliac crest breadth compared with many other early australopiths, whereas Homo ergaster KNM WT 15000 surprisingly also has a relatively anterioposteriorly short iliac crest. StW 573 and StW 431 appear to resemble humans in having a long ischium compared with Sts 14 and KNM WT 15000. A Quadratic Discriminant Function Analysis of morphology compared with other Plio-Pleistocene hominins and a dataset of modern humans and hominoids shows that, while Lovejoy's heuristic model of the Ardipithecus ramidus os coxae falls with Pongo or in an indeterminate group, StW 573 and StW 431 from Sterkfontein Member 4 are consistently classified together with modern humans. Although clearly exhibiting the classic "basin shaped" bipedal pelvis, Sts 14 (also from Sterkfontein), AL 288-1 Australopithecus afarensis, MH2 Australopithecus sediba and KNM-WT 15000 occupy a position more peripheral to modern humans, and in some analyses are assigned to an indeterminate outlying group. Our findings strongly support the existence of two species of Australopithecus at Sterkfontein and the variation we observe in os coxae morphology in early hominins is also likely to reflect multiple forms of bipedality.
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BACKGROUND: In the absence of left-sided cardiac/pulmonary disease, functional tricuspid regurgitation (FTR) is referred to as isolated or idiopathic. Relationships between left ventricular diastolic dysfunction (DD) and FTR remain unknown. OBJECTIVES: The purpose of this study was to investigate the prevalence, incidence, and outcome of DD in patients with idiopathic FTR. METHODS: Adults without structural heart disease were identified. Severe DD was defined by ≥3 of 4 abnormal DD parameters (medial e', medial E/e', TR velocity, left atrial volume index) and ≥ moderate DD by ≥2. Propensity-score matching was performed (3:1) between each less-than-severe TR group and severe TR based on age, sex, body mass index, and comorbidities. RESULTS: Among 30,428 patients, FTR was absent in 73%, mild in 22%, moderate in 4%, and severe in 0.4%. In the propensity-matched sample, severe DD was present in 2%, 6%, 9%, and 13% patients, and ≥ moderate DD in 11%, 18%, 28%, and 48%, respectively (P < 0.001). The probability of heart failure with preserved ejection fraction using the H2FPEF score increased with increasing FTR (median 29.7%, 45.5%, 61.4%, and 88.7%, respectively), as did the prevalence of impaired left atrial strain <24% (35%, 48%, and 69% in mild, moderate, and severe TR). Incident severe and ≥ moderate DD developed more frequently with increasing FTR (HR: 8.45 [95% CI: 2.60-27.50] and HR: 2.82 [95% CI: 1.40-5.69], respectively for ≥ moderate vs no FTR) over a median of 3.0 years. Findings were confirmed in patients without lung disease or right ventricular enlargement. Over a median of 5.0 years, patients with ≥ moderate FTR and DD had the greatest risk of worse outcomes (multivariable P < 0.001). The association between TR and adverse outcomes was significantly diminished in the absence of DD. CONCLUSIONS: Diastolic dysfunction, increased heart failure with preserved ejection fraction probability, and impaired left atrial strain are commonly present in patients with idiopathic FTR, suggesting that the latter may not be truly isolated. Patients with FTR without DD or heart failure are at increased risk of incident DD. Patients with FTR and DD display worse outcomes.
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BACKGROUND: Mitral annular calcification (MAC) is a progressive degenerative process associated with comorbidities and increased mortality. A staging system that considers extramitral cardiac damage in MAC may help improve patient selection for mitral valve interventions. OBJECTIVES: This study sought to develop a transthoracic echocardiogram (TTE)-based cardiac staging system in patients with MAC and significant mitral valve dysfunction and assess its prognostic utility. METHODS: We retrospectively evaluated all adults who underwent TTE over 1 year at Mayo Clinic with MAC and significant mitral valve dysfunction defined as mitral stenosis and/or at least moderate mitral regurgitation. Patients were categorized into 5 stages according to extramitral cardiac damage by TTE. All-cause mortality and heart failure hospitalization were assessed. RESULTS: For the 953 included patients, the mean age was 76.2 ± 10.7 years, and 54.0% were women. Twenty-eight (2.9%) patients were classified in stages 0 to 1, 499 (52.4%) in stage 2, 115 (12.1%) in stage 3, and 311 (32.6%) in stage 4. At the 3.8-year follow-up, mortality was significantly higher in patients in stages 2 to 4 compared to stages 0 to 1 and increased with each stage. Survival differences were maintained after adjustment for age, diabetes mellitus, and glomerular filtration rate. The rate of heart failure hospitalization was significantly higher in stages 3 and 4 compared to stages 0 to 1. Similar results were observed in subgroup analysis in patients with moderate or severe MAC, predominant mitral stenosis, or predominant mitral regurgitation. CONCLUSIONS: Using the proposed extramitral cardiac damage staging system in patients with MAC and significant mitral valve dysfunction, more advanced stages are associated with higher mortality.
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Calcinosis , Insuficiencia Cardíaca , Insuficiencia de la Válvula Mitral , Estenosis de la Válvula Mitral , Válvula Mitral , Valor Predictivo de las Pruebas , Índice de Severidad de la Enfermedad , Humanos , Femenino , Masculino , Anciano , Estudios Retrospectivos , Válvula Mitral/fisiopatología , Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/fisiopatología , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/mortalidad , Estenosis de la Válvula Mitral/fisiopatología , Estenosis de la Válvula Mitral/diagnóstico por imagen , Estenosis de la Válvula Mitral/mortalidad , Calcinosis/fisiopatología , Calcinosis/diagnóstico por imagen , Calcinosis/mortalidad , Factores de Tiempo , Anciano de 80 o más Años , Factores de Riesgo , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/etiología , Persona de Mediana Edad , Minnesota , Medición de Riesgo , Pronóstico , EcocardiografíaRESUMEN
BACKGROUND AND AIMS: Incidence and types of secondary tricuspid regurgitation (TR) are not well defined in atrial fibrillation (AFib) and sinus rhythm (SR). Atrial secondary TR (A-STR) is associated with pre-existing AFib; however, close to 50% of patients with A-STR do not have AFib. The aim of this study was to assess incidence, types, and outcomes of ≥ moderate TR in AFib vs. SR. METHODS: Adults with and without new-onset AFib without structural heart disease or ≥ moderate TR at baseline were followed for the development of ≥ moderate TR. Tricuspid regurgitation types were pacemaker, left-sided valve disease, left ventricular (LV) dysfunction, pulmonary hypertension (PH), isolated ventricular, and A-STR. RESULTS: Among 1359 patients with AFib and 20 438 in SR, 109 and 378 patients developed ≥ moderate TR, respectively. The individual types of TR occurred more frequently in AFib related to the higher pacemaker implantation rates (1.12 vs. 0.19 per 100 person-years, P < .001), larger right atrial size (median 78 vs. 53â mL, P < .001), and higher pulmonary pressures (median 30 vs. 28â mmHg, P < .001). The most common TR types irrespective of rhythm were LV dysfunction-TR and A-STR. Among patients in SR, those with A-STR were older, predominantly women with more diastolic abnormalities and higher pulmonary pressures. All types of secondary TR were associated with all-cause mortality, highest in PH-TR and LV dysfunction-TR. CONCLUSIONS: New-onset AFib vs. SR conferred a higher risk of the individual TR types related to sequelae of AFib and higher pacemaker implantation rates, although the distribution of TR types was similar. Secondary TR was universally associated with increased mortality.
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Fibrilación Atrial , Insuficiencia de la Válvula Tricúspide , Humanos , Insuficiencia de la Válvula Tricúspide/epidemiología , Insuficiencia de la Válvula Tricúspide/fisiopatología , Fibrilación Atrial/epidemiología , Fibrilación Atrial/complicaciones , Femenino , Masculino , Anciano , Incidencia , Persona de Mediana Edad , Marcapaso ArtificialRESUMEN
INTRODUCTION: We investigated the effect of perivascular spaces (PVS) volume on speeded executive function (sEF), as mediated by white matter hyperintensities (WMH) volume and plasma glial fibrillary acidic protein (GFAP) in neurodegenerative diseases. METHODS: A mediation analysis was performed to assess the relationship between neuroimaging markers and plasma biomarkers on sEF in 333 participants clinically diagnosed with Alzheimer's disease/mild cognitive impairment, frontotemporal dementia, or cerebrovascular disease from the Ontario Neurodegenerative Disease Research Initiative. RESULTS: PVS was significantly associated with sEF (c = -0.125 ± 0.054, 95% bootstrap confidence interval [CI] [-0.2309, -0.0189], p = 0.021). This effect was mediated by both GFAP and WMH. DISCUSSION: In this unique clinical cohort of neurodegenerative diseases, we demonstrated that the effect of PVS on sEF was mediated by the presence of elevated plasma GFAP and white matter disease. These findings highlight the potential utility of imaging and plasma biomarkers in the current landscape of therapeutics targeting dementia. HIGHLIGHTS: Perivascular spaces (PVS) and white matter hyperintensities (WMH) are imaging markers of small vessel disease. Plasma glial fibrillary protein acidic protein (GFAP) is a biomarker of astroglial injury. PVS, WMH, and GFAP are relevant in executive dysfunction from neurodegeneration. PVS's effect on executive function was mediated by GFAP and white matter disease.
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Biomarcadores , Función Ejecutiva , Proteína Ácida Fibrilar de la Glía , Sistema Glinfático , Imagen por Resonancia Magnética , Enfermedades Neurodegenerativas , Sustancia Blanca , Humanos , Proteína Ácida Fibrilar de la Glía/sangre , Femenino , Masculino , Anciano , Función Ejecutiva/fisiología , Enfermedades Neurodegenerativas/sangre , Biomarcadores/sangre , Sistema Glinfático/patología , Sistema Glinfático/diagnóstico por imagen , Sustancia Blanca/patología , Sustancia Blanca/diagnóstico por imagen , Disfunción Cognitiva/sangre , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/patología , Demencia Frontotemporal/sangre , Demencia Frontotemporal/patología , Demencia Frontotemporal/diagnóstico por imagen , Trastornos Cerebrovasculares/sangre , Trastornos Cerebrovasculares/diagnóstico por imagen , Trastornos Cerebrovasculares/patología , Encéfalo/patología , Encéfalo/diagnóstico por imagen , Estudios de Cohortes , Persona de Mediana EdadRESUMEN
In response to calls for public engagement on human genome editing (HGE), which intensified after the 2018 He Jiankui scandal that resulted in the implantation of genetically modified embryos, we detail an anticipatory approach to the governance of HGE. By soliciting multidisciplinary experts' input on the drivers and uncertainties of HGE development, we developed a set of plausible future scenarios to ascertain publics values-specifically, their hopes and concerns regarding the novel technology and its applications. In turn, we gathered a subset of multidisciplinary experts to propose governance recommendations for HGE that incorporate identified publics' values. These recommendations include: (1) continued participatory public engagement; (2) international harmonization and transparency of multiple governance levers such as professional and scientific societies, funders, and regulators; and (3) development of a formal whistleblower framework.
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Background: Pulmonary hypertension (PH) has been shown to be associated with worse outcomes in patients with aortic regurgitation (AR) in small older studies. Objectives: The authors sought to evaluate the prevalence of PH in patients with severe AR, its impact on mortality and symptoms, and regression after aortic valve replacement (AVR). Methods: A total of 821 consecutive patients with chronic ≥ moderate-severe AR on echocardiography from 2004 to 2019 were retrospectively analyzed. PH was defined as right ventricular systolic pressure (RVSP) >40 mm Hg on transthoracic echocardiogram (mild-moderate PH: RVSP 40-59 mm Hg, severe PH: RVSP > 60 mm Hg). Clinical and echocardiographic data were extracted from the electronic medical record and echocardiographic reports. The diastolic function and filling pressures were manually assessed and checked, and the left ventricular (LV) volumes were traced by a level 3-trained echocardiographer. The primary objectives were prevalence of PH in patients with ≥ moderate-severe AR, its risk associations and impact on all-cause mortality as the primary outcome. Secondary outcomes were impact of PH on symptoms and change in RVSP at discharge post-AVR. Logistic and Cox proportional hazards regression were used to analyze these outcomes. Results: The mean age was 61.2 ± 17 years, and 162 (20%) were women. Mild-moderate PH was present in 91 (11%) patients and severe PH in 27 (3%). Larger LV size, elevated LV filling pressures, and ≥ moderate tricuspid regurgitation were associated with PH. During follow-up of 7.3 (6.3-7.9) years, 188 patients died. Compared to those without PH, risk of mortality was higher in mild-moderate PH (adjusted HR: 1.59 (95% CI: 1.07-2.36) (P = 0.021)) and severe PH (adjusted HR: 2.90 (95% CI: 1.63-5.15) (P < 0.001)). Symptoms were also more prevalent in those with PH (P = 0.004). Of 396 patients who underwent AVR during the study period, 57 had PH. AVR similarly improved survival in patients without and with PH (P for interaction = 0.23), and there was regression in RVSP (≥8 mm Hg drop) at discharge post-AVR in 35/57 (61%) patients with PH. Conclusions: PH was present in 14% of patients with AR and was associated with higher mortality and symptoms. The survival benefit of AVR was similar in patients without and with PH.
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While precision medicine applications of radiomics analysis are promising, differences in image acquisition can cause "batch effects" that reduce reproducibility and affect downstream predictive analyses. Harmonization methods such as ComBat have been developed to correct these effects, but evaluation methods for quantifying batch effects are inconsistent. In this study, we propose the use of the multivariate statistical test PERMANOVA and the Robust Effect Size Index (RESI) to better quantify and characterize batch effects in radiomics data. We evaluate these methods in both simulated and real radiomics features extracted from full-field digital mammography (FFDM) data. PERMANOVA demonstrated higher power than standard univariate statistical testing, and RESI was able to interpretably quantify the effect size of site at extremely large sample sizes. These methods show promise as more powerful and interpretable methods for the detection and quantification of batch effects in radiomics studies.
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Mamografía , Humanos , Mamografía/métodos , Femenino , Análisis Multivariante , Neoplasias de la Mama/diagnóstico por imagen , Reproducibilidad de los Resultados , Procesamiento de Imagen Asistido por Computador/métodos , RadiómicaRESUMEN
BACKGROUND: Early menarche is an established risk factor for breast cancer but its molecular contribution to tumor biology and prognosis remains unclear. METHODS: We profiled transcriptome-wide gene expression in breast tumors (N = 846) and tumor-adjacent normal tissues (N = 666) from women in the Nurses' Health Studies (NHS) to investigate whether early menarche (age < 12) is associated with tumor molecular and prognostic features in women with breast cancer. Multivariable linear regression and pathway analyses using competitive gene set enrichment analysis were conducted in both tumor and adjacent-normal tissue and externally validated in TCGA (N = 116). Subgroup analyses stratified on ER-status based on the tumor were also performed. PAM50 signatures were used for tumor molecular subtyping and to generate proliferation and risk of recurrence scores. We created a gene expression score using LASSO regression to capture early menarche based on 28 genes from FDR-significant pathways in breast tumor tissue in NHS and tested its association with 10-year disease-free survival in both NHS (N = 836) and METABRIC (N = 952). RESULTS: Early menarche was significantly associated with 369 individual genes in adjacent-normal tissues implicated in extracellular matrix, cell adhesion, and invasion (FDR ≤ 0.1). Early menarche was associated with upregulation of cancer hallmark pathways (18 significant pathways in tumor, 23 in tumor-adjacent normal, FDR ≤ 0.1) related to proliferation (e.g. Myc, PI3K/AKT/mTOR, cell cycle), oxidative stress (e.g. oxidative phosphorylation, unfolded protein response), and inflammation (e.g. pro-inflammatory cytokines IFN α and IFN γ ). Replication in TCGA confirmed these trends. Early menarche was associated with significantly higher PAM50 proliferation scores (ß = 0.082 [0.02-0.14]), odds of aggressive molecular tumor subtypes (basal-like, OR = 1.84 [1.18-2.85] and HER2-enriched, OR = 2.32 [1.46-3.69]), and PAM50 risk of recurrence score (ß = 4.81 [1.71-7.92]). Our NHS-derived early menarche gene expression signature was significantly associated with worse 10-year disease-free survival in METABRIC (N = 952, HR = 1.58 [1.10-2.25]). CONCLUSIONS: Early menarche is associated with more aggressive molecular tumor characteristics and its gene expression signature within tumors is associated with worse 10-year disease-free survival among women with breast cancer. As the age of onset of menarche continues to decline, understanding its relationship to breast tumor characteristics and prognosis may lead to novel secondary prevention strategies.
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Neoplasias de la Mama , Perfilación de la Expresión Génica , Menarquia , Recurrencia Local de Neoplasia , Transcriptoma , Humanos , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/mortalidad , Menarquia/genética , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Persona de Mediana Edad , Pronóstico , Adulto , Biomarcadores de Tumor/genética , Factores de Riesgo , Regulación Neoplásica de la Expresión Génica , Factores de EdadRESUMEN
BACKGROUND: Aortic valve calcification(AVC) is prognostic in patients with aortic stenosis(AS). We assessed the AVC prognostic value in nonsevere AS patients. METHODS AND RESULTS: We conducted a retrospective study of 395 patients with nonsevere AS, LV ejection fraction ≥50%. The Agatston method was used for computed tomography AVC assessment. The log-rank test determined the best AVC cutoffs for survival under medical surveillance: 1185â AU in men and 850 in women, lower than the established-cutoffs for severe AS(2064AU in men and 1274 in women). Patients were divided into three AVC groups based on these cutoffs: low(<1185â AU men and <850 women), sub-severe(1185-2064AU men and 850-1274 women) and severe(>2064AU men and >1274 women). Of 395 patients(mean age 73 ± 12 years, 60.5% men, aortic valve area 1.23 ± 0.30cm2, mean pressure gradient 28 ± 8â mmHg), 218 underwent aortic valve intervention(AVI) and 158 deaths occurred during follow-up, 82 before AVI. Median survival time under medical surveillance was 2.1[0.7-4.9]years. Compared to the low AVC group, both sub-severe and severe AVC groups had higher risk for all-cause death under medical surveillance after comprehensive adjustment including echocardiographic AS severity and coronary artery calcium score(all p ≤ 0.006); while mortality risk was similar between sub-severe and severe AVC groups(all p ≥ 0.2). This mortality risk pattern persisted in the overall survival analysis after adjustment for AVI. AVI was protective of all-cause death in the sub-severe and severe AVC(all p ≤ 0.01), but not in the low AVC groups. CONCLUSIONS: Sub-severe AVC is a robust risk-stratification parameter in patients with nonsevere AS and may inform AVI timing.
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BACKGROUND: Despite the close association between aortic stenosis (AS) and cardiac damage (CD), it is unclear if CD is limited to patients with moderate and severe AS and which factors affect its progression. Although altered valvular hemodynamic status may drive the development of CD in AS, commonly occurring comorbidities may contribute. OBJECTIVES: The aim of this study was to determine the prevalence of and factors associated with CD in mild AS. METHODS: This retrospective study included 9,611 patients with mild AS (peak aortic valve velocity [Vmax] 2-3 m/s and description of abnormal aortic valve) from 2010 through 2021. CD was staged using the Genereux classification. RESULTS: All but 20% (n = 1,901; stage 0) of patients with mild AS demonstrated CD: 1,613 (17%) stage 1, 4,843 (50%) stage 2, 891 (9%) stage 3, and 363 (4%) stage 4. Patients with higher stages had more comorbidities (hypertension, heart failure, ischemic heart disease, stroke, peripheral arterial disease, chronic kidney disease, chronic pulmonary disease, and diabetes mellitus) but had valvular hemodynamic status similar to those without CD. CD stage did not worsen with higher Vmax range (stage >1 in 64% with Vmax <2.5 m/s vs 61% with Vmax ≥2.5 m/s) but increased with the number of comorbidities, with stage >1 occurring in 50%, 53%, 60%, 66%, 72%, and 73% in the presence of 0, 1, 2, 3, 4, and 5 or more comorbidities, respectively. CONCLUSIONS: CD was highly prevalent in patients with mild AS. Among patients with mild AS, there was no relationship between the degree of CD and AS severity; instead, CD was highly associated with comorbidities.
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BACKGROUND: Nutrition guidance for athletes must consider a range of variables to effectively support individuals in meeting energy and nutrient needs. Resistance exercise is a widely adopted training method in athlete preparation and rehabilitation and therefore is one such variable that will influence nutrition guidance. Given its prominence, the capacity to meaningfully quantify resistance exercise energy expenditure will assist practitioners and researchers in providing nutrition guidance. However, the significant contribution of anaerobic metabolism makes quantifying energy expenditure of resistance exercise challenging. OBJECTIVE: The aim of this scoping review was to investigate the methods used to assess resistance exercise energy expenditure. METHODS: A literature search of Medline, SPORTDiscus, CINAHL and Web of Science identified studies that included an assessment of resistance exercise energy expenditure. Quality appraisal of included studies was performed using the Rosendal Scale. RESULTS: A total of 19,867 studies were identified, with 166 included after screening. Methods to assess energy expenditure included indirect calorimetry (n = 136), blood lactate analysis (n = 25), wearable monitors (n = 31) and metabolic equivalents (n = 4). Post-exercise energy expenditure was measured in 76 studies. The reported energy expenditure values varied widely between studies. CONCLUSIONS: Indirect calorimetry is widely used to estimate energy expenditure. However, given its limitations in quantifying glycolytic contribution, indirect calorimetry during and immediately following exercise combined with measures of blood lactate are likely required to better quantify total energy expenditure. Due to the cumbersome equipment and technical expertise required, though, along with the physical restrictions the equipment places on participants performing particular resistance exercises, indirect calorimetry is likely impractical for use outside of the laboratory setting, where metabolic equivalents may be a more appropriate method.
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Bispecific antibodies (bsAbs) have recently emerged as a promising platform for the treatment of several conditions, most importantly cancer. Based on the combination of two different antigen-binding motifs in a single macromolecule; bsAbs can either display the combined characteristics of their parent antibodies, or new therapeutic features, inaccessible by the sole combination of two distinct antibodies. While bsAbs are traditionally produced by molecular biology techniques, the chemical development of bsAbs holds great promises and strategies have just begun to surface. In this context, we took advantage of a chemical strategy based on the use of the Ugi reaction for the site-selective conjugation of whole antibodies and coupled the resulting conjugates in a bioorthogonal manner with Fab fragments, derived from various antibodies. We thus managed to produce five different bsAbs with 2 : 1 valency, with yields ranging from 20 % to 48 %, and showed that the affinity of the parent antibody was preserved in all bsAbs. We further demonstrated the interest of our strategy by producing two other bsAbs behaving as cytotoxic T cell engagers with IC50 values in the picomolar range inâ vitro.
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OBJECTIVES: To investigate whether a history of traumatic brain injury (TBI) is associated with greater long-term grey-matter loss in patients with mild cognitive impairment (MCI). METHODS: 85 patients with MCI were identified, including 26 with a previous history of traumatic brain injury (MCI[TBI-]) and 59 without (MCI[TBI+]). Cortical thickness was evaluated by segmenting T1-weighted MRI scans acquired longitudinally over a 2-year period. Bayesian multilevel modelling was used to evaluate group differences in baseline cortical thickness and longitudinal change, as well as group differences in neuropsychological measures of executive function. RESULTS: At baseline, the MCI[TBI+] group had less grey matter within right entorhinal, left medial orbitofrontal and inferior temporal cortex areas bilaterally. Longitudinally, the MCI[TBI+] group also exhibited greater longitudinal declines in left rostral middle frontal, the left caudal middle frontal and left lateral orbitofrontal areas sover the span of 2 years (median = 1-2%, 90%HDI [-0.01%: -0.001%], probability of direction (PD) = 90-99%). The MCI[TBI+] group also displayed greater longitudinal declines in Trail-Making-Test (TMT)-derived ratio (median: 0.737%, 90%HDI: [0.229%: 1.31%], PD = 98.8%) and differences scores (median: 20.6%, 90%HDI: [-5.17%: 43.2%], PD = 91.7%). CONCLUSIONS: Our findings support the notion that patients with MCI and a history of TBI are at risk of accelerated neurodegeneration, displaying greatest evidence for cortical atrophy within the left middle frontal and lateral orbitofrontal frontal cortex. Importantly, these results suggest that long-term TBI-mediated atrophy is more pronounced in areas vulnerable to TBI-related mechanical injury, highlighting their potential relevance for diagnostic forms of intervention in TBI.
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Lesiones Traumáticas del Encéfalo , Disfunción Cognitiva , Sustancia Gris , Imagen por Resonancia Magnética , Humanos , Disfunción Cognitiva/etiología , Disfunción Cognitiva/patología , Disfunción Cognitiva/diagnóstico por imagen , Masculino , Femenino , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Lesiones Traumáticas del Encéfalo/patología , Lesiones Traumáticas del Encéfalo/complicaciones , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Anciano , Persona de Mediana Edad , Estudios Longitudinales , Pruebas Neuropsicológicas , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Teorema de BayesRESUMEN
INTRODUCTION: Although prior studies indicate that a QTc > 500 ms on a single baseline 12-lead electrocardiogram (ECG) is associated with significantly increased risk of arrhythmic events in long QT syndrome (LQTS), less is known about the risk of persistent QT prolongation. We sought to determine QTc persistence and its prognostic effect on breakthrough cardiac events (BCEs) among pediatric patients treated for LQTS. METHODS: We performed a retrospective analysis of 433 patients with LQTS evaluated, risk-stratified, and undergoing active guideline-based LQTS treatment between 1999 and 2019. BCEs were defined as arrhythmogenic syncope/seizure, sudden cardiac arrest (SCA), appropriate VF-terminating ICD shock, and sudden cardiac death (SCD). RESULTS: During the median follow-up of 5.5 years (interquartile range [IQR] = 3-9), 32 (7%) patients experienced a total of 129 BCEs. A maximum QTc threshold of 520 ms and median QTc threshold of 490 ms were determined to be strong predictors for BCEs. A landmark analysis controlling for age, sex, genotype, and symptomatic status demonstrated models utilizing both the median QTc and maximum QTc demonstrated the highest discriminatory value (c-statistic = 0.93-0.95). Patients in the high-risk group (median QTc > 490 ms and maximum QTc > 520 ms) had a significantly lower BCE free survival (70%-81%) when compared to patients in both medium-risk (93%-97%) and low-risk (98%-99%) groups. CONCLUSIONS: The risk of BCE among patients treated for LQTS increases not only based upon their maximum QTc, but also their median QTc (persistence of QTc prolongation). Patients with a maximum QTc > 520 ms and median QTc > 490 ms over serial 12-lead ECGs are at the highest risk of BCE while on guideline-directed medical therapy.
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Potenciales de Acción , Muerte Súbita Cardíaca , Electrocardiografía , Frecuencia Cardíaca , Síndrome de QT Prolongado , Valor Predictivo de las Pruebas , Humanos , Masculino , Síndrome de QT Prolongado/diagnóstico , Síndrome de QT Prolongado/fisiopatología , Femenino , Estudios Retrospectivos , Niño , Medición de Riesgo , Factores de Riesgo , Adolescente , Muerte Súbita Cardíaca/prevención & control , Muerte Súbita Cardíaca/etiología , Preescolar , Factores de Tiempo , Factores de Edad , Lactante , Resultado del Tratamiento , Sistema de Conducción Cardíaco/fisiopatologíaRESUMEN
BACKGROUND: Stress echocardiographic (SE) testing is an important modality in cardiovascular risk stratification and obstructive coronary artery disease assessment. Binary sex-based parameters are classically used for the interpretation of these studies, even among transgender women (TGW). Coronary artery disease is a leading cause of morbidity and mortality in this population. Yet, it remains unclear whether TGW exhibit a distinct stress testing profile from their cisgender counterparts. METHODS: Using a matched case-control study design, the authors compared the echocardiographic stress testing profiles of TGW (n = 43) with those of matched cisgender men (CGM; n = 84) and cisgender women (CGW; n = 86) at a single center. Relevant data, including demographics, comorbidities, and cardiac testing data, were manually extracted from the patients' charts. RESULTS: The prevalence of hypertension and dyslipidemia was similar between TGW and CGW and lower than that of CGM (P = .003 and P = .009, respectively). The majority of comorbidities and laboratory values were similar. On average, TGW had higher heart rates than CGM (P = .002) and had lower blood pressures than CGM and CGW (P < .05). TGW's double product and metabolic equivalents were similar to those among CGW and lower than those of CGM (P = .016 and P = .018, respectively). On echocardiography, left ventricular end-diastolic and end-systolic diameters among TGW were similar to those of CGW but lower than those of CGM (P = .023 and P = .018, respectively). Measures of systolic and diastolic function, except for exercise mitral valve E/e' ratio, which was lower in TGW than CGW (P = .029), were largely similar among the three groups. There was no difference in the wall motion score index, and therefore, no difference in the percentage of positive SE test results. CONCLUSIONS: This study shows, for the first time, that TGW have a SE profile that is distinct from that of their cisgender counterparts. Larger, multicenter, prospective studies are warranted to further characterize the SE profile of TGW.
Asunto(s)
Ecocardiografía de Estrés , Personas Transgénero , Humanos , Femenino , Ecocardiografía de Estrés/métodos , Persona de Mediana Edad , Masculino , Personas Transgénero/estadística & datos numéricos , Adulto , Estudios de Casos y Controles , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/epidemiología , Minnesota/epidemiología , Prevalencia , Estudios RetrospectivosRESUMEN
An inflammation-resolving polysialic acid-decorated PLGA nanoparticle (PolySia-NP) has been developed to treat geographic atrophy/age-related macular degeneration and other conditions caused by macrophage and complement over-activation. While PolySia-NPs have demonstrated pre-clinical efficacy, this study evaluated its systemic and intraocular safety. PolySia-NPs were evaluated in vitro for mutagenic activity using Salmonella strains and E. coli, with and without metabolic activation; cytotoxicity was evaluated based on its interference with normal mitosis. PolySia-NPs were administered intravenously in CD-1 mice and Sprague Dawley rats and assessed for survival and toxicity. Intravitreal (IVT) administration in Dutch Belted rabbits and non-human primates was assessed for ocular or systemic toxicity. In vitro results indicate that PolySia-NPs did not induce mutagenicity or cytotoxicity. Intravenous administration did not show clastogenic activity, effects on survival, or toxicity. A single intravitreal (IVT) injection and two elevated repeat IVT doses of PolySia-NPs separated by 7 days in rabbits showed no signs of systemic or ocular toxicity. A single IVT inoculation of PolySia-NPs in non-human primates demonstrated no adverse clinical or ophthalmological effects. The demonstration of systemic and ocular safety of PolySia-NPs supports its advancement into human clinical trials as a promising therapeutic approach for systemic and retinal degenerative diseases caused by chronic immune activation.