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2.
Mater Horiz ; 11(14): 3352-3363, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38686501

RESUMEN

Controlling the multi-level assembly and morphological properties of conjugated polymers through structural manipulation has contributed significantly to the advancement of organic electronics. In this work, a redox active conjugated polymer, TPT-TT, composed of alternating 1,4-(2-thienyl)-2,5-dialkoxyphenylene (TPT) and thienothiophene (TT) units is reported with non-covalent intramolecular S⋯O and S⋯H-C interactions that induce controlled main-chain planarity and solid-state order. As confirmed by density functional theory (DFT) calculations, these intramolecular interactions influence the main chain conformation, promoting backbone planarization, while still allowing dihedral rotations at higher kinetic energies (higher temperature), and give rise to temperature-dependent aggregation properties. Thermotropic liquid crystalline (LC) behavior is confirmed by cross-polarized optical microscopy (CPOM) and closely correlated with multiple thermal transitions observed by differential scanning calorimetry (DSC). This LC behavior allows us to develop and utilize a thermal annealing treatment that results in thin films with notable long-range order, as shown by grazing-incidence X-ray diffraction (GIXD). Specifically, we identified a first LC phase, ranging from 218 °C to 107 °C, as a nematic phase featuring preferential face-on π-π stacking and edge-on lamellar stacking exhibiting a large extent of disorder and broad orientation distribution. A second LC phase is observed from 107 °C to 48 °C, as a smectic A phase featuring sharp, highly ordered out-of-plane lamellar stacking features and sharp tilted backbone stacking peaks, while the structure of a third LC phase with a transition at 48 °C remains unclear, but resembles that of the solid state at ambient temperature. Furthermore, the significance of thermal annealing is evident in the ∼3-fold enhancement of the electrical conductivity of ferric tosylate-doped annealed films reaching 55 S cm-1. More importantly, thermally annealed TPT-TT films exhibit both a narrow distribution of charge-carrier mobilities (1.4 ± 0.1) × 10-2 cm2 V-1 s-1 along with a remarkable device yield of 100% in an organic field-effect transistor (OFET) configuration. This molecular design approach to obtain highly ordered conjugated polymers in the solid state affords a deeper understanding of how intramolecular interactions and repeat-unit symmetry impact liquid crystallinity, solution aggregation, solution to solid-state transformation, solid-state morphology, and ultimately device applications.

3.
J Chem Inf Model ; 64(6): 1966-1974, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38437714

RESUMEN

Chemical diversity is challenging to describe objectively. Despite this, various notions of chemical diversity are used throughout the medicinal chemistry optimization process in drug discovery. In this work, we show the usefulness of considering exploited vectors during different phases of the drug design process to provide a quantitative and objective description of chemical diversity. We have developed a concise and fast approach to enumerate and analyze the exploited vector patterns (EVPs) of molecular compound series, which can then be used in archetypal compound selection tasks, from hit matter identification to hit expansion and lead optimization. We first show that EVPs can be used to assess the progressibility of compounds in a fragment library design exercise. By considering EVPs, we then show how a set of compounds can be prioritized for hit expansion using EVP-based, customizable diversity sampling approaches, reducing the time taken and mitigating human biases. We also show that EVPs are a useful tool to analyze SAR data, offering the chance to uncover correlations between different vectors without predetermining the molecular scaffold structures. The codes used to perform these tasks are presented as easy-to-use Jupyter notebooks, which can be readily adapted for further related tasks.


Asunto(s)
Quimioinformática , Descubrimiento de Drogas , Humanos , Diseño de Fármacos , Estructura Molecular , Química Farmacéutica
4.
Nat Cancer ; 5(3): 420-432, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38172341

RESUMEN

Checkpoint inhibition (CPI), particularly that targeting the inhibitory coreceptor programmed cell death protein 1 (PD-1), has transformed oncology. Although CPI can derepress cancer (neo)antigen-specific αß T cells that ordinarily show PD-1-dependent exhaustion, it can also be efficacious against cancers evading αß T cell recognition. In such settings, γδ T cells have been implicated, but the functional relevance of PD-1 expression by these cells is unclear. Here we demonstrate that intratumoral TRDV1 transcripts (encoding the TCRδ chain of Vδ1+ γδ T cells) predict anti-PD-1 CPI response in patients with melanoma, particularly those harboring below average neoantigens. Moreover, using a protocol yielding substantial numbers of tissue-derived Vδ1+ cells, we show that PD-1+Vδ1+ cells display a transcriptomic program similar to, but distinct from, the canonical exhaustion program of colocated PD-1+CD8+ αß T cells. In particular, PD-1+Vδ1+ cells retained effector responses to TCR signaling that were inhibitable by PD-1 engagement and derepressed by CPI.


Asunto(s)
Neoplasias , Subgrupos de Linfocitos T , Humanos , Subgrupos de Linfocitos T/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Perfilación de la Expresión Génica , Inmunoterapia
5.
Heliyon ; 10(1): e23339, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38169784

RESUMEN

The US population suffers 1.5 million head injuries annually, of which mild traumatic brain injuries (mTBI) comprise 75%. Many individuals subsequently experience long-lasting negative symptoms, including anxiety. Previous rat-based work in our laboratory has shown that mTBI changes neuronal counts in the hippocampus and amygdala, regions associated with anxiety. Specifically, mTBI increased neuronal death in the dorsal CA1 sub-region of the hippocampus, but attenuated it in the medial (MeA) and the basolateral nuclei of the amygdala nine days following injury, which was associated with greater anxiety. We have also shown that glucocorticoid receptor (GR) antagonism prior to concomitant stress and mTBI extinguishes anxiety-like behaviors. Using immunohistochemistry, this study examines the expression of brain-derived neurotrophic factor (BDNF) following social defeat and mTBI, and whether this is affected by prior glucocorticoid receptor antagonism as a potential mechanism behind these anxiety and neuronal differences. Here, stress and mTBI upregulate BDNF in the MeA, and both GR and mineralocorticoid receptor antagonism downregulate BDNF in the dorsal hippocampal CA1 and dentate gyrus, as well as the central nucleus of the amygdala. These findings suggest BDNF plays a role in the mechanism underlying neuronal changes following mTBI in amygdalar and hippocampal subregions, and may participate in stress elicited changes to neural plasticity in these regions. Taken together, these results suggest an essential role for BDNF in the development of anxiety behaviors following concurrent stress and mTBI.

6.
AJR Am J Roentgenol ; 222(1): e2329347, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37315017

RESUMEN

Amyloidoses are a complex group of clinical diseases that result from progressive organ dysfunction due to extracellular protein misfolding and deposition. The two most common types of cardiac amyloidosis are transthyretin amyloidosis (ATTR) and light-chain (AL) amyloidosis. Diagnosis of ATTR cardiomyopathy (ATTR-CM) is challenging owing to its phenotypic similarity to other more common cardiac conditions, the perceived rarity of the disease, and unfamiliarity with its diagnostic algorithms; endomyocardial biopsy was historically required for diagnosis. However, myocardial scintigraphy using bone-seeking tracers has shown high accuracy for detection of ATTR-CM and has become a key noninvasive diagnostic test for the condition, receiving support from professional society guidelines and transforming prior diagnostic paradigms. This AJR Expert Panel Narrative Review describes the role of myocardial scintigraphy using bone-seeking tracers in the diagnosis of ATTR-CM. The article summarizes available tracers, acquisition techniques, interpretation and reporting considerations, diagnostic pitfalls, and gaps in the current literature. The critical need for monoclonal testing of patients with positive scintigraphy results to differentiate ATTR-CM from AL cardiac amyloidosis is highlighted. Recent updates in guideline recommendations that emphasize the importance of a qualitative visual assessment are also discussed.


Asunto(s)
Neuropatías Amiloides Familiares , Cardiomiopatías , Cardiopatías , Imagen de Perfusión Miocárdica , Humanos , Neuropatías Amiloides Familiares/diagnóstico por imagen , Neuropatías Amiloides Familiares/patología , Cintigrafía , Cardiopatías/diagnóstico por imagen , Cardiomiopatías/diagnóstico por imagen
8.
BMC Med Educ ; 23(1): 866, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37968656

RESUMEN

BACKGROUND: Imperial College School of Medicine, London UK, introduced a new curriculum in 2019, with a focus on the GMC outcomes for graduates, and pedagogy best practice. The new curriculum included formative assessments, named engagement and feedback assessments (EFAs), to support learning, and attainment in the summative examinations. The aims of this study were to assess the validity of EFAs and to determine whether they have utility as a modified form of programmatic assessment to inform decision-making regarding possible interventions by measuring and analysing attendance at and performance in these formative events. METHODS: Seven hundred and sixty-one students were included in the study and assessment results were included for academic years 2019/20 to 2020/21. Forty-one data points per student, (27 in Year 1 and 14 in Year 2) were used, to compare EFA scores with the summative performance. Attendance was monitored through engagement with the EFAs. RESULTS: Cohort 1 (enrolled 2019): In year 1, EFAs were associated with summative exam scores (overall r = 0.63, p < 0.001). Year 2, EFA scores were also associated with summative scores (overall r = 0.57, p < 0.001), including the clinical practical assessment (r = 0.45, p < 0.001). Missing two or more EFAs was associated with a significant increase in the likelihood of failing one or more summative examinations in the first year (OR: 7.97, 95% CI 2.65-34.39) and second year (OR: 3.20, 95% CI 1.74-5.95). Missing more than two EFAs in their first year was also associated with a higher risk of failing a summative examination in the second year (OR: 2.47, 95% CI 1.33-4.71). Students who increased their attendance between year 1 and 2 fared better in summative assessment than those who maintained poor attendance, whereas those that reduced their attendance fared worse than those that maintained high attendance. Cohort 2 (enrolled 2020): Analysis of cohort 2 supported these findings and in this cohort missing two or more EFAs was again associated with an increased likelihood of failing a summative examination (OR = 4.00, 95% CI = 2.02-7.90). CONCLUSION: Our EFA model has validity in predicting performance in summative assessments and can inform prospective interventions to support students' learning. Enhancing attendance and engagement can improve outcomes.


Asunto(s)
Educación de Pregrado en Medicina , Estudiantes de Medicina , Humanos , Retroalimentación , Evaluación Educacional/métodos , Estudios Prospectivos , Educación de Pregrado en Medicina/métodos
9.
Chem Sci ; 14(34): 9175-9185, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37655035

RESUMEN

Building on the extensive exploration of metal oxide and metal halide perovskites, metal nitride perovskites represent a largely unexplored class of materials. We report a multi-tier computational screening of this chemical space. From a pool of 3660 ABN3 compositions covering I-VIII, II-VII, III-VI and IV-V oxidation state combinations, 279 are predicted to be chemically feasible. The ground-state structures of the 25 most promising candidate compositions were explored through enumeration over octahedral tilt systems and global optimisation. We predict 12 dynamically and thermodynamically stable nitride perovskite materials, including YMoN3, YWN3, ZrTaN3, and LaMoN3. These feature significant electric polarisation and low predicted switching electric field, showing similarities with metal oxide perovskites and making them attractive for ferroelectric memory devices.

10.
JCO Oncol Pract ; 19(11): 1053-1057, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37738533

RESUMEN

PURPOSE: Biosimilars are clinically equivalent to branded products yet cost significantly less. Interchangeability is a US Food and Drug Administration (FDA) designation that allows generic drugs to be substituted for reference drugs at the pharmacy, without a physician's consent. Currently, no oncologic biosimilar has FDA approval for interchangeability. METHODS: Building on pharmacy auto-substitution processes with therapeutic interchange, Plan-Do-Study-Act methodology was used to automate conversions from reference biological products to Pharmacy and Therapeutics-/Physician-approved biosimilars. After establishing the baseline metrics, cycle 1 focused on full staff education (completed July 2020) with systematic pharmacy-driven biosimilar conversion initiated in September 2020 for rituximab, trastuzumab, and bevacizumab. Physician-initiated conversion of Neulasta biosimilar products was encouraged but not mandated. During cycle 2 (May 1, 2021-November 30, 2021), pharmacy-driven Neulasta biosimilar conversion was mandated. In cycle 3 (December 1, 2021-April 30, 2023), stakeholder education was reinforced and the sustainability of conversions was confirmed. RESULTS: Systematic pharmacy-driven conversion to biosimilar products improved over cycles 1 and 2 from baseline: 1.8% to 90.3% for rituximab, 9.2% to 89.7% for trastuzumab, and 20.5% to 96.1% for bevacizumab. Physician-driven biosimilar conversion for Neulasta was lower at 12.7% through April 2021. Pharmacy-driven Neulasta biosimilar conversion was initiated during cycle 2, resulting in a conversion rate of 39.7%. The conversion rates remained sustainable through April 2023. CONCLUSION: Pharmacy-driven auto-substitution of biosimilar products results in rapid and statistically significant biosimilar adoption. The pharmacy-based substitution approach was found to be far more effective than physician-driven substitution. Rapid conversion from branded products to FDA-approved biosimilar is feasible, measurable, and sustainable and can be scaled. Barriers to Neulasta conversion warrant further investigation.


Asunto(s)
Biosimilares Farmacéuticos , Farmacia , Estados Unidos , Humanos , Biosimilares Farmacéuticos/farmacología , Biosimilares Farmacéuticos/uso terapéutico , Rituximab , Bevacizumab/farmacología , Bevacizumab/uso terapéutico , United States Food and Drug Administration , Aprobación de Drogas , Trastuzumab/farmacología
11.
J Allergy Clin Immunol ; 152(6): 1520-1540, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37562754

RESUMEN

BACKGROUND: Elicitation of allergic contact dermatitis (ACD), an inflammatory type 4 hypersensitivity disease, induces skin infiltration by polyclonal effector CD8 αß T cells and precursors of tissue-resident memory T (TRM) cells. Because TRM have long-term potential to contribute to body-surface immunoprotection and immunopathology, their local regulation needs a fuller understanding. OBJECTIVE: We sought to investigate how TRM-cell maturation might be influenced by innate-like T cells pre-existing within many epithelia. METHODS: This study examined CD8+ TRM-cell maturation following hapten-induced ACD in wild-type mice and in strains harboring altered compartments of dendritic intraepidermal γδ T cells (DETCs), a prototypic tissue-intrinsic, innate-like T-cell compartment that reportedly regulates ACD, but by no elucidated mechanism. RESULTS: In addition to eliciting CD8 TRM, ACD induced DETC activation and an intimate coregulatory association of the 2 cell types. This depended on DETC sensing IFN-γ produced by CD8 cells and involved programmed death-ligand 1 (PD-L1). Thus, in mice lacking DETC or lacking IFN-γ receptor solely on γδ cells, ACD-elicited CD8 T cells showed enhanced proliferative and effector potentials and reduced motility, collectively associated with exaggerated ACD pathology. Comparable dysregulation was elicited by PD-L1 blockade in vitro, and IFN-γ-regulated PD-L1 expression was a trait of human skin-homing and intraepithelial γδ T cells. CONCLUSIONS: The size and quality of the tissue-infiltrating CD8 T-cell response during ACD can be profoundly regulated by local innate-like T cells responding to IFN-γ and involving PD-L1. Thus, interindividual and tissue-specific variations in tissue-intrinsic lymphocytes may influence responses to allergens and other challenges and may underpin inflammatory pathologies such as those repeatedly observed in γδ T-cell-deficient settings.


Asunto(s)
Dermatitis Alérgica por Contacto , Interferón gamma , Animales , Humanos , Ratones , Antígeno B7-H1 , Linfocitos T CD8-positivos/patología , Dermatitis Alérgica por Contacto/patología , Piel/patología
12.
J Vet Intern Med ; 37(5): 1766-1771, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37469251

RESUMEN

BACKGROUND: Ultrasound-determined gallbladder wall thickness is widely used to aid in the diagnosis of gallbladder disease, but no reference values supported by published measurement data are available in dogs. HYPOTHESIS/OBJECTIVE: Establish normal thickness of the gallbladder wall in dogs. ANIMALS: Fifty-three dogs presented to a referral hospital and required abdominal ultrasound examination for reasons unrelated to primary hepatobiliary disease. METHODS: Cross-sectional observational study recruiting dogs requiring abdominal ultrasound examination. A standard sequence of gallbladder wall images was recorded for later review. Inclusion criteria were normal ultrasonographic hepatobiliary, pancreatic, and small intestinal findings. Exclusion was determined by 2 European College of Veterinary Internal Medicine (ECVIM)-certified veterinary internists blinded to gallbladder wall thickness data. Dogs were excluded if they had inadequate medical records, a previous history of hepatobiliary, gastrointestinal, or pancreatic disease likely to impact the biliary system (eg, chronic vomiting, nausea, jaundice, diarrhea), unexplained increases in liver enzyme activities, hypoalbuminemia, or ascites. Gallbladder wall thickness was determined by 2 European College of Veterinary Diagnostic Imaging (ECVDI)-certified veterinary radiologists working together to generate a consensus for each dog. The final output was the maximum normal wall thickness for this population of dogs. RESULTS: The upper limit for gallbladder wall thickness in 53 fasted (8 hours) dogs <40 kg was 1.30 mm (90% confidence interval, 1.19-1.41). CONCLUSIONS AND CLINICAL IMPORTANCE: Normal gallbladder wall thickness in dogs is lower than previously reported. Additional studies are required to determine potential effects of body weight and the optimal cut-off to distinguish between healthy and diseased gallbladders.


Asunto(s)
Enfermedades de los Perros , Enfermedades de la Vesícula Biliar , Humanos , Perros , Animales , Estudios Transversales , Enfermedades de la Vesícula Biliar/diagnóstico por imagen , Enfermedades de la Vesícula Biliar/veterinaria , Ultrasonografía/veterinaria , Tracto Gastrointestinal , Enfermedades de los Perros/diagnóstico por imagen
13.
Adv Med Educ Pract ; 14: 373-380, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37101695

RESUMEN

Objective: This study compared knowledge attainment and student enjoyment and engagement between clinical case vignette, patient-testimony videos and mixed reality (MR) teaching via the Microsoft HoloLens 2, all delivered remotely to third year medical students. The feasibility of conducting MR teaching on a large scale was also assessed. Setting & Participants: Medical students in Year 3 at Imperial College London participated in three online teaching sessions, one in each format. All students were expected to attend these scheduled teaching sessions and to complete the formative assessment. Inclusion of their data used as part of the research trial was optional. Primary and Secondary Outcome Measures: The primary outcome measure was performance on a formative assessment, which served to compare knowledge attainment between three forms of online learning. Moreover, we aimed to explore student engagement with each form of learning via a questionnaire, and also feasibility of applying MR as a teaching tool on a large scale. Comparisons between performances on the formative assessment between the three groups were investigated using a repeated measures two-way ANOVA. Engagement and enjoyment were also analysed in the same manner. Results: A total of 252 students participated in the study. Knowledge attainment of students using MR was comparable with the other two methods. Participants reported higher enjoyment and engagement (p<0.001) for the case vignette method, compared with MR and video-based teaching. There was no difference in enjoyment or engagement ratings between MR and the video-based methods. Conclusion: This study demonstrated that the implementation of MR is an effective, acceptable, and feasible way of teaching clinical medicine to undergraduate students on a large scale. However, case-based tutorials were found to be favoured most by students. Future work could further explore the best uses for MR teaching within the medical curriculum.

14.
Chem Soc Rev ; 52(9): 3098-3169, 2023 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-37070570

RESUMEN

In the last century, molecular crystals functioned predominantly as a means for determining the molecular structures via X-ray diffraction, albeit as the century came to a close the response of molecular crystals to electric, magnetic, and light fields revealed that the physical properties of molecular crystals were as rich as the diversity of molecules themselves. In this century, the mechanical properties of molecular crystals have continued to enhance our understanding of the colligative responses of weakly bound molecules to internal frustration and applied forces. Here, the authors review the main themes of research that have developed in recent decades, prefaced by an overview of the particular considerations that distinguish molecular crystals from traditional materials such as metals and ceramics. Many molecular crystals will deform themselves as they grow under some conditions. Whether they respond to intrinsic stress or external forces or interactions among the fields of growing crystals remains an open question. Photoreactivity in single crystals has been a leading theme in organic solid-state chemistry; however, the focus of research has been traditionally on reaction stereo- and regio-specificity. However, as light-induced chemistry builds stress in crystals anisotropically, all types of motions can be actuated. The correlation between photochemistry and the responses of single crystals-jumping, twisting, fracturing, delaminating, rocking, and rolling-has become a well-defined field of research in its own right: photomechanics. The advancement of our understanding requires theoretical and high-performance computations. Computational crystallography not only supports interpretations of mechanical responses, but predicts the responses itself. This requires the engagement of classical force-field based molecular dynamics simulations, density functional theory-based approaches, and the use of machine learning to divine patterns to which algorithms can be better suited than people. The integration of mechanics with the transport of electrons and photons is considered for practical applications in flexible organic electronics and photonics. Dynamic crystals that respond rapidly and reversibly to heat and light can function as switches and actuators. Progress in identifying efficient shape-shifting crystals is also discussed. Finally, the importance of mechanical properties to milling and tableting of pharmaceuticals in an industry still dominated by active ingredients composed of small molecule crystals is reviewed. A dearth of data on the strength, hardness, Young's modulus, and fracture toughness of molecular crystals underscores the need for refinement of measurement techniques and conceptual tools. The need for benchmark data is emphasized throughout.

15.
Nat Commun ; 14(1): 1304, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36944642

RESUMEN

Cooperativity is used by living systems to circumvent energetic and entropic barriers to yield highly efficient molecular processes. Cooperative structural transitions involve the concerted displacement of molecules in a crystalline material, as opposed to typical molecule-by-molecule nucleation and growth mechanisms which often break single crystallinity. Cooperative transitions have acquired much attention for low transition barriers, ultrafast kinetics, and structural reversibility. However, cooperative transitions are rare in molecular crystals and their origin is poorly understood. Crystals of 2-dimensional quinoidal terthiophene (2DQTT-o-B), a high-performance n-type organic semiconductor, demonstrate two distinct thermally activated phase transitions following these mechanisms. Here we show reorientation of the alkyl side chains triggers cooperative behavior, tilting the molecules like dominos. Whereas, nucleation and growth transition is coincident with increasing alkyl chain disorder and driven by forming a biradical state. We establish alkyl chain engineering as integral to rationally controlling these polymorphic behaviors for novel electronic applications.

16.
J Mater Chem C Mater ; 10(10): 3784-3795, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36325578

RESUMEN

Four novel compositions containing chalcogenide layers, adopting the Ba3M2O5M'2Ch2 layered structure have been identified: Ba3Sc2O5Cu2Se2, Ba3Y2O5Cu2S2, Ba3Sc2O5Ag2Se2 and Ba3In2O5Ag2Se2. A comprehensive comparison of experimental and computational results providing the crystallographic and electronic structure of the compounds under investigation has been conducted. Materials were synthesised at 800 °C under vacuum using a conventional ceramic synthesis route with combination of binary oxide and chalcogenide precursors. We report their structures determined by Rietveld refinement of X-ray powder diffraction patterns, and band gaps determined from optical measurements, which range from 1.44 eV to 3.04 eV. Through computational modelling we can also present detailed band structures and propose that, based on their predicted transport properties, Ba3Sc2O5Ag2Se2 has potential as a visible light photocatalyst and Ba3Sc2O5Cu2Se2 is of interest as a p-type transparent conductor. These four novel compounds are part of a larger series of sixteen compounds adopting the Ba3M2O5M'2Ch2 structure that we have considered, of which approximately half are stable and can be synthesized. Analysis of the compounds that cannot be synthesized from this group allows us to identify why compounds containing either M = La, or silver sulfide chalcogenide layers, cannot be formed in this structure type.

17.
Front Cell Dev Biol ; 10: 1036602, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36438561

RESUMEN

Years of important research has revealed that cells heavily invest in regulating their size. Nevertheless, it has remained unclear why accurate size control is so important. Our recent study using hematopoietic stem cells (HSCs) in vivo indicates that cellular enlargement is causally associated with aging. Here, we present an overview of these findings and their implications. Furthermore, we performed a broad literature analysis to evaluate the potential of cellular enlargement as a new aging hallmark and to examine its connection to previously described aging hallmarks. Finally, we highlight interesting work presenting a correlation between cell size and age-related diseases. Taken together, we found mounting evidence linking cellular enlargement to aging and age-related diseases. Therefore, we encourage researchers from seemingly unrelated areas to take a fresh look at their data from the perspective of cell size.

18.
JAMA Cardiol ; 7(10): 1036-1044, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-36069809

RESUMEN

Importance: Transthyretin amyloid cardiomyopathy (ATTR-CM) is a form of heart failure (HF) with preserved ejection fraction (HFpEF). Technetium Tc 99m pyrophosphate scintigraphy (PYP) enables ATTR-CM diagnosis. It is unclear which patients with HFpEF have sufficient risk of ATTR-CM to warrant PYP. Objective: To derive and validate a simple ATTR-CM score to predict increased risk of ATTR-CM in patients with HFpEF. Design, Setting, and Participants: Retrospective cohort study of 666 patients with HF (ejection fraction ≥ 40%) and suspected ATTR-CM referred for PYP at Mayo Clinic, Rochester, Minnesota, from May 10, 2013, through August 31, 2020. These data were analyzed September 2020 through December 2020. A logistic regression model predictive of ATTR-CM was derived and converted to a point-based ATTR-CM risk score. The score was further validated in a community ATTR-CM epidemiology study of older patients with HFpEF with increased left ventricular wall thickness ([WT] ≥ 12 mm) and in an external (Northwestern University, Chicago, Illinois) HFpEF cohort referred for PYP. Race was self-reported by the participants. In all cohorts, both case patients and control patients were definitively ascertained by PYP scanning and specialist evaluation. Main Outcomes and Measures: Performance of the derived ATTR-CM score in all cohorts (referral validation, community validation, and external validation) and prevalence of a high-risk ATTR-CM score in 4 multinational HFpEF clinical trials. Results: Participant cohorts included were referral derivation (n = 416; 13 participants [3%] were Black and 380 participants [94%] were White; ATTR-CM prevalence = 45%), referral validation (n = 250; 12 participants [5%]were Black and 228 participants [93%] were White; ATTR-CM prevalence = 48% ), community validation (n = 286; 5 participants [2%] were Black and 275 participants [96%] were White; ATTR-CM prevalence = 6% ), and external validation (n = 66; 23 participants [37%] were Black and 36 participants [58%] were White; ATTR-CM prevalence = 39%). Score variables included age, male sex, hypertension diagnosis, relative WT more than 0.57, posterior WT of 12 mm or more, and ejection fraction less than 60% (score range -1 to 10). Discrimination (area under the receiver operating characteristic curve [AUC] 0.89; 95% CI, 0.86-0.92; P < .001) and calibration (Hosmer-Lemeshow; χ2 = 4.6; P = .46) were strong. Discrimination (AUC ≥ 0.84; P < .001 for all) and calibration (Hosmer-Lemeshow χ2 = 2.8; P = .84; Hosmer-Lemeshow χ2 = 4.4; P = .35; Hosmer-Lemeshow χ2 = 2.5; P = .78 in referral, community, and external validation cohorts, respectively) were maintained in all validation cohorts. Precision-recall curves and predictive value vs prevalence plots indicated clinically useful classification performance for a score of 6 or more (positive predictive value ≥25%) in clinically relevant ATTR-CM prevalence (≥10% of patients with HFpEF) scenarios. In the HFpEF clinical trials, 11% to 35% of male and 0% to 6% of female patients had a high-risk (≥6) ATTR-CM score. Conclusions and Relevance: A simple 6 variable clinical score may be used to guide use of PYP and increase recognition of ATTR-CM among patients with HFpEF in the community. Further validation in larger and more diverse populations is needed.


Asunto(s)
Amiloidosis , Cardiomiopatías , Insuficiencia Cardíaca , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/epidemiología , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/epidemiología , Humanos , Masculino , Prealbúmina , Radiofármacos , Estudios Retrospectivos , Volumen Sistólico , Pirofosfato de Tecnecio Tc 99m
19.
Proc Natl Acad Sci U S A ; 119(34): e2201541119, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35943978

RESUMEN

Whereas pathogen-specific T and B cells are a primary focus of interest during infectious disease, we have used COVID-19 to ask whether their emergence comes at a cost of broader B cell and T cell repertoire disruption. We applied a genomic DNA-based approach to concurrently study the immunoglobulin-heavy (IGH) and T cell receptor (TCR) ß and δ chain loci of 95 individuals. Our approach detected anticipated repertoire focusing for the IGH repertoire, including expansions of clusters of related sequences temporally aligned with SARS-CoV-2-specific seroconversion, and enrichment of some shared SARS-CoV-2-associated sequences. No significant age-related or disease severity-related deficiencies were noted for the IGH repertoire. By contrast, whereas focusing occurred at the TCRß and TCRδ loci, including some TCRß sequence-sharing, disruptive repertoire narrowing was almost entirely limited to many patients aged older than 50 y. By temporarily reducing T cell diversity and by risking expansions of nonbeneficial T cells, these traits may constitute an age-related risk factor for COVID-19, including a vulnerability to new variants for which T cells may provide key protection.


Asunto(s)
Inmunidad Adaptativa , COVID-19 , Cadenas Pesadas de Inmunoglobulina , Receptores de Antígenos de Linfocitos T alfa-beta , Receptores de Antígenos de Linfocitos T , SARS-CoV-2 , Inmunidad Adaptativa/genética , Anciano , Linfocitos B/inmunología , COVID-19/genética , COVID-19/inmunología , Sitios Genéticos , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T alfa-beta/genética , SARS-CoV-2/inmunología , Seroconversión , Linfocitos T/inmunología
20.
Res Dev Disabil ; 128: 104298, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35816978

RESUMEN

BACKGROUND: Self-report is important for measuring health outcomes; however, most research in intellectual disability (ID) relies on proxy report. The lack of cognitively accessible measures is one barrier to accurate self-reporting by individuals with ID. AIMS: This paper describes the process of adapting self-report measures of health status, health-related quality of life, and environment for use by individuals with ID and presents evidence on their usability (accessibility), usefulness (independent self-report), and reliability (internal consistency and test-retest). METHODS AND PROCEDURES: We used an inclusive research approach, in which we collaborated with adults with ID to revise, cognitively test, and pilot test cognitively accessible self-report measures. Technology supported the independent completion of measures. We assessed usability, usefulness, and reliability of these measures in 41 adults with ID. OUTCOMES AND RESULTS: The resulting measures are useful (independently completed) and usable (elicit a range of responses), with modest reliability (internal consistency and test-retest). CONCLUSIONS AND IMPLICATIONS: Self- report by adults with ID is feasible. A key element of this measure adaptation process was engaging adults with ID. More research is needed to understand the reliability and validity of the adapted measures and the characteristics of the population for whom they are most usable.


Asunto(s)
Discapacidad Intelectual , Adulto , Estado de Salud , Humanos , Discapacidad Intelectual/diagnóstico , Psicometría , Calidad de Vida , Reproducibilidad de los Resultados , Autoinforme
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