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1.
Nat Mater ; 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39060469

RESUMEN

Conducting polymers are mixed ionic-electronic conductors that are emerging candidates for neuromorphic computing, bioelectronics and thermoelectrics. However, fundamental aspects of their many-body correlated electron-ion transport physics remain poorly understood. Here we show that in p-type organic electrochemical transistors it is possible to remove all of the electrons from the valence band and even access deeper bands without degradation. By adding a second, field-effect gate electrode, additional electrons or holes can be injected at set doping states. Under conditions where the counterions are unable to equilibrate in response to field-induced changes in the electronic carrier density, we observe surprising, non-equilibrium transport signatures that provide unique insights into the interaction-driven formation of a frozen, soft Coulomb gap in the density of states. Our work identifies new strategies for substantially enhancing the transport properties of conducting polymers by exploiting non-equilibrium states in the coupled system of electronic charges and counterions.

2.
Front Immunol ; 15: 1374301, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38835765

RESUMEN

Background: Human immunodeficiency virus (HIV) affects nearly 40 million people globally, with roughly 80% of all people living with HIV receiving antiretroviral therapy. Antiretroviral treatment suppresses viral load in peripheral tissues but does not effectively penetrate the blood-brain barrier. Thus, viral reservoirs persist in the central nervous system and continue to produce low levels of inflammatory factors and early viral proteins, including the transactivator of transcription (Tat). HIV Tat is known to contribute to chronic neuroinflammation and synaptodendritic damage, which is associated with the development of cognitive, motor, and/or mood problems, collectively known as HIV-associated neurocognitive disorders (HAND). Cannabinoid anti-inflammatory effects are well documented, but therapeutic utility of cannabis remains limited due to its psychotropic effects, including alterations within brain regions encoding reward processing and motivation, such as the nucleus accumbens. Alternatively, inhibiting monoacylglycerol lipase (MAGL) has demonstrated therapeutic potential through interactions with the endocannabinoid system. Methods: The present study utilized a reward-related operant behavioral task to quantify motivated behavior in female Tat transgenic mice treated with vehicle or MAGL inhibitor MJN110 (1 mg/kg). Brain tissue was collected to assess dendritic injury and neuroinflammatory profiles, including dendritic microtubule-associated protein (MAP2ab) intensity, microglia density, microglia morphology, astrocyte density, astrocytic interleukin-1ß (IL-1ß) colocalization, and various lipid mediators. Results: No significant behavioral differences were observed; however, MJN110 protected against Tat-induced dendritic injury by significantly upregulating MAP2ab intensity in the nucleus accumbens and in the infralimbic cortex of Tat(+) mice. No or only minor effects were noted for Iba-1+ microglia density and/or microglia morphology. Further, Tat increased GFAP+ astrocyte density in the infralimbic cortex and GFAP+ astrocytic IL-1ß colocalization in the nucleus accumbens, with MJN110 significantly reducing these measures in Tat(+) subjects. Lastly, selected HETE-related inflammatory lipid mediators in the striatum were downregulated by chronic MJN110 treatment. Conclusions: These findings demonstrate anti-inflammatory and neuroprotective properties of MJN110 without cannabimimetic behavioral effects and suggest a promising alternative to cannabis for managing neuroinflammation.


Asunto(s)
VIH-1 , Monoacilglicerol Lipasas , Enfermedades Neuroinflamatorias , Animales , Femenino , Humanos , Ratones , Complejo SIDA Demencia/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/virología , Encéfalo/patología , Modelos Animales de Enfermedad , Infecciones por VIH/tratamiento farmacológico , VIH-1/fisiología , Ratones Transgénicos , Microglía/efectos de los fármacos , Microglía/metabolismo , Monoacilglicerol Lipasas/antagonistas & inhibidores , Monoacilglicerol Lipasas/metabolismo , Enfermedades Neuroinflamatorias/tratamiento farmacológico , Enfermedades Neuroinflamatorias/etiología , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/metabolismo
3.
Adv Mater ; 36(25): e2314062, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38558210

RESUMEN

Doping is a crucial strategy to enhance the performance of various organic electronic devices. However, in many cases, the random distribution of dopants in conjugated polymers leads to the disruption of the polymer microstructure, severely constraining the achievable performance of electronic devices. Here, it is shown that by ion-exchange doping polythiophene-based P[(3HT)1-x-stat-(T)x] (x = 0 (P1), 0.12 (P2), 0.24 (P3), and 0.36 (P4)), remarkably high electrical conductivity of >400 S cm-1 and power factor of >16 µW m-1 K-2 are achieved for the random copolymer P3, ranking it among highest ever reported for unaligned P3HT-based films, significantly higher than that of P1 (<40 S cm-1, <4 µW m-1 K-2). Although both polymers exhibit comparable field-effect transistor hole mobilities of ≈0.1 cm2 V-1 s-1 in the pristine state, after doping, Hall effect measurements indicate that P3 exhibits a large Hall mobility up to 1.2 cm2 V-1 s-1, significantly outperforming that of P1 (0.06 cm2 V-1 s-1). GIWAXS measurement determines that the in-plane π-π stacking distance of doped P3 is 3.44 Å, distinctly shorter than that of doped P1 (3.68 Å). These findings contribute to resolving the long-standing dopant-induced-disorder issues in P3HT and serve as an example for achieving fast charge transport in highly doped polymers for efficient electronics.

4.
Adv Mater ; 36(28): e2310480, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38669281

RESUMEN

Conjugated polymers are promising materials for thermoelectric applications, however, at present few effective and well-understood strategies exist to further advance their thermoelectric performance. Here a new model system is reported for a better understanding of the key factors governing their thermoelectric properties: aligned, ribbon-phase poly[2,5-bis(3-dodecylthiophen-2-yl)thieno[3,2-b]thiophene] (PBTTT) doped by ion-exchange doping. Using a range of microstructural and spectroscopic methods, the effect of controlled incorporation of tie-chains between the crystalline domains is studied through blending of high and low molecular weight chains. The tie chains provide efficient transport pathways between crystalline domains and lead to significantly enhanced electrical conductivity of 4810 S cm-1, which is not accompanied by a reduction in Seebeck coefficient or a large increase in thermal conductivity. Respectable power factors of 173 µW m-1 K-2 are demonstrated in this model system. The approach is generally applicable to a wide range of semicrystalline conjugated polymers and could provide an effective pathway for further enhancing their thermoelectric properties and overcome traditional trade-offs in optimization of thermoelectric performance.

5.
Cancer Med ; 13(7): e7163, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38597129

RESUMEN

BACKGROUND: Ovarian cancer is the most lethal of all gynecological cancers. Cancer Antigen 125 (CA125) is the best-performing ovarian cancer biomarker which however is still not effective as a screening test in the general population. Recent literature reports additional biomarkers with the potential to improve on CA125 for early detection when using longitudinal multimarker models. METHODS: Our data comprised 180 controls and 44 cases with serum samples sourced from the multimodal arm of UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS). Our models were based on Bayesian change-point detection and recurrent neural networks. RESULTS: We obtained a significantly higher performance for CA125-HE4 model using both methodologies (AUC 0.971, sensitivity 96.7% and AUC 0.987, sensitivity 96.7%) with respect to CA125 (AUC 0.949, sensitivity 90.8% and AUC 0.953, sensitivity 92.1%) for Bayesian change-point model (BCP) and recurrent neural networks (RNN) approaches, respectively. One year before diagnosis, the CA125-HE4 model also ranked as the best, whereas at 2 years before diagnosis no multimarker model outperformed CA125. CONCLUSIONS: Our study identified and tested different combination of biomarkers using longitudinal multivariable models that outperformed CA125 alone. We showed the potential of multivariable models and candidate biomarkers to increase the detection rate of ovarian cancer.


Asunto(s)
Aprendizaje Profundo , Neoplasias Ováricas , Humanos , Femenino , Teorema de Bayes , Estudios de Casos y Controles , Neoplasias Ováricas/epidemiología , Biomarcadores de Tumor , Detección Precoz del Cáncer/métodos , Curva ROC
6.
J Phys Chem B ; 128(13): 3249-3257, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38507573

RESUMEN

Spin-casting of molecularly doped polymer solution mixtures is one of the commonly used methods to obtain conductive organic semiconductor films. In spin-casted films, electronic interaction between the dopant and polymer is one of the crucial factors that dictates the doping efficiency. Here, we investigate excitonic couplings using ultrafast two-dimensional electronic spectroscopy to examine the different types of electronic interactions in ion pairs of the prototype F4TCNQ-doped P3HT polymer system in a precursor solution mixture for spin-casting. Off-diagonal peaks in the 2D spectra clearly establish the excitonic coupling between P3HT+ and F4TCNQ- ions in solution. The observed excitonic coupling is the direct manifestation of a Coulombic interaction between the ion pair. The excited-state lifetime of F4TCNQ- in ion pairs shows biexponential decay at 30 and 200 fs, which hints toward the presence of a heterogeneous population with different interaction strengths. To examine the nature of these different types of interactions in solution mixtures, we study the system using molecular dynamics simulations on a fully solvated model employing the generalized Amber force field. We retrieve three dominant interaction modes of F4TCNQ anions with P3HT: side chain, π-stack, and slipped stack. To quantify these interactions, we complement our studies with electronic structure calculations, which reveal the excitonic coupling strengths of ∼ 75 cm-1 for side chain, ∼ 150 cm-1 for π-π-stack, and ∼69 cm-1 for slipped stack. These various interaction modes provide information about the key geometries of the seed structures in precursor solution mixtures, which may determine the final structures in spin-casted films. The insights gained from our study may guide new strategies to control and ultimately tune Coulomb interactions in polymer-dopant solutions.

7.
Laryngoscope ; 134(1): 287-296, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37458368

RESUMEN

OBJECTIVE: Subglottic stenosis (SGS) may result from prolonged intubation where fibrotic scar tissue narrows the airway. The scar forms by differentiated myofibroblasts secreting excessive extracellular matrix (ECM). TGF-ß1 is widely accepted as a regulator of fibrosis; however, it is unclear how biomechanical pathways co-regulate fibrosis. Therefore, we phenotyped fibroblasts from pediatric patients with SGS to explore how key signaling pathways, TGF-ß and Hippo, impact scarring and assess the impact of inhibiting these pathways with potential therapeutic small molecules SB525334 and DRD1 agonist dihydrexidine hydrochloride (DHX). METHODS: Laryngeal fibroblasts isolated from subglottic as well as distal control biopsies of patients with evolving and maturing subglottic stenosis were assessed by α-smooth muscle actin immunostaining and gene expression for α-SMA, FN, HGF, and CTGF markers. TGF-ß and Hippo signaling pathways were modulated during TGF-ß1-induced fibrosis using the inhibitor SB525334 or DHX and analyzed by RT-qPCR for differential gene expression and atomic force microscopy for ECM stiffness. RESULTS: SGS fibroblasts exhibited higher α-SMA staining and greater inflammatory cytokine and fibrotic marker expression upon TGF-ß1 stimulation (p < 0.05). SB525334 restored levels to baseline by reducing SMAD2/3 nuclear translocation (p < 0.0001) and pro-fibrotic gene expression (p < 0.05). ECM stiffness of stenotic fibroblasts was greater than healthy fibroblasts and was restored to baseline by Hippo pathway modulation using SB525334 and DHX (p < 0.01). CONCLUSION: We demonstrate that distinct fibroblast phenotypes from diseased and healthy regions of pediatric SGS patients respond differently to TGF-ß1 stimulation, and SB525334 has the superior potential for subglottic stenosis treatment by simultaneously modulating TGF-ß and Hippo signaling pathways. LEVEL OF EVIDENCE: NA Laryngoscope, 134:287-296, 2024.


Asunto(s)
Cicatriz , Factor de Crecimiento Transformador beta1 , Humanos , Niño , Factor de Crecimiento Transformador beta1/metabolismo , Cicatriz/patología , Constricción Patológica/patología , Fibrosis , Fibroblastos/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Células Cultivadas
8.
Int J Pediatr Otorhinolaryngol ; 176: 111803, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38043185

RESUMEN

INTRODUCTION: Button batteries (BB) are a source of significant morbidity and mortality in young children. Little data is available regarding associations between esophageal impaction location and outcomes or need for surveillance imaging. METHODS: All patients treated at a single institution following BB ingestion between 2018 and 2022 were included for retrospective chart review. RESULTS: Twenty patients were treated at our institution BBs were located, or most significant damage observed, in the cervical esophagus (n = 10, 50 %), followed by thoracic esophagus (n = 6, 30 %), and abdominal esophagus (n = 4, 20 %). Patients with cervical esophageal impaction were younger (482 [370-866] days), than those with thoracic (1395 [871-2369] days) or abdominal esophageal impaction (2021.5 [1230.5-3419.5] days) (p = 0.003). Zargar Mucosal Injury Grade was significantly more severe in patients with cervical button battery impaction; 8/10 (80 %) had a ≥Grade IIIB injury, compared to 2/6 (33.3 %) thoracic impactions and 0/4 (0 %) abdominal impactions (p = 0.002). All patients who developed persistent esophageal stenosis (n = 6) had cervical battery impactions (6, 60 %, p = 0.015). Both TEFs (2/2) had anterior facing anode, while both (2/2) esophageal perforations had posterior. Only 1/20 (5 %) patients, and 1/7 (14.3 %) with serious complications, had a serious complication detected on routine, rather than clinically indicated follow-up surveillance. CONCLUSIONS: In our population, cervical BB impaction occurred more frequently in younger children, was associated with more severe mucosal injury, and had higher risk of stenosis. Nearly all complications were detected on clinically indicated rather than postoperative surveillance imaging.


Asunto(s)
Cuerpos Extraños , Niño , Humanos , Preescolar , Estudios Retrospectivos , Cuerpos Extraños/complicaciones , Cuerpos Extraños/diagnóstico por imagen , Cuerpos Extraños/cirugía , Esófago/diagnóstico por imagen , Esófago/lesiones , Suministros de Energía Eléctrica , Ingestión de Alimentos
9.
Laryngoscope ; 134(2): 807-814, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37658705

RESUMEN

OBJECTIVE: Severe subglottic stenosis develops as a response to intubation in 1% of the >200,000 neonatal intensive care unit infants per year and may require laryngotracheal reconstruction (LTR) with autologous hyaline cartilage. Although effective, LTR is limited by comorbidities, severity of stenosis, and graft integration. In children, there is a significant incidence of restenosis requiring revision surgery. Tissue engineering has been proposed to develop alterative grafting options to improve outcomes and eliminate donor-site morbidity. Our objective is to engineer a decellularized, channel-laden xenogeneic cartilage graft, that we deployed in a proof-of-concept, neonatal porcine LTR model. METHODS: Meniscal porcine cartilage was freeze-thawed and washed with pepsin/elastase to decellularize and create microchannels. A 6 × 10-mm decellularized cartilage graft was then implanted in 4 infant pigs in an anterior cricoid split. Airway patency and host response were monitored endoscopically until sacrifice at 12 weeks, when the construct phenotype, cricoid expansion, mechanics, and histomorphometry were evaluated. RESULTS: The selective digestion of meniscal components yielded decellularized cartilage with cell-size channels. After LTR with decellularized meniscus, neonatal pigs were monitored via periodic endoscopy observing re-epithelization, integration, and neocartilage formation. At 12 weeks, the graft appeared integrated and exhibited airway expansion of 4 mm in micro-CT and endoscopy. Micro-CT revealed a larger lumen compared with age-matched controls. Finally, histology showed significant neocartilage formation. CONCLUSION: Our neonatal porcine LTR model with a decellularized cartilage graft is a novel approach to tissue engineered pediatric LTR. This pilot study sets the stage for "off-the-shelf" graft procurement and future optimization of MEND for LTR. LEVEL OF EVIDENCE: NA Laryngoscope, 134:807-814, 2024.


Asunto(s)
Laringoestenosis , Procedimientos de Cirugía Plástica , Lactante , Recién Nacido , Niño , Humanos , Animales , Porcinos , Proyectos Piloto , Constricción Patológica/cirugía , Cartílago/trasplante , Laringoestenosis/cirugía
10.
Gynecol Oncol ; 179: 123-130, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37980767

RESUMEN

OBJECTIVE: UKCTOCS provides an opportunity to explore symptoms in preclinical invasive epithelial ovarian cancer (iEOC). We report on symptoms in women with pre-clinical (screen-detected) cancers (PC) compared to clinically diagnosed (CD) cancers. METHODS: In UKCTOCS, 202638 postmenopausal women, aged 50-74 were randomly allocated (April 17, 2001-September 29, 2005) 2:1:1 to no screening or annual screening till Dec 31,2011, using a multimodal or ultrasound strategy. Follow-up was through national registries. An outcomes committee adjudicated on OC diagnosis, histotype, stage. Eligible women were those diagnosed with iEOC at primary censorship (Dec 31, 2014). Symptom details were extracted from trial clinical-assessment forms and medical records. Descriptive statistics were used to compare symptoms in PC versus CD women with early (I/II) and advanced (III/IV/unable to stage) stage high-grade-serous (HGSC) cancer. ISRCTN-22488978; ClinicalTrials.gov-NCT00058032. RESULTS: 1133 (286PC; 847CD) women developed iEOC. Median age (years) at diagnosis was earlier in PC compared to CD (66.8PC, 68.7CD, p = 0.0001) group. In the PC group, 48% (112/234; 90%, 660/730CD) reported symptoms when questioned. Half PC (50%, 13/26PC; 36%, 29/80CD; p = 0.213) women with symptomatic HGSC had >1symptom, with abdominal symptoms most common, both in early (62%, 16/26, PC; 53% 42/80, CD; p = 0.421) and advanced (57%, 49/86, PC; 74%, 431/580, CD; p = 0.001) stages. In symptomatic early-stage HGSC, compared to CD, PC women reported more gastrointestinal (change in bowel habits and dyspepsia) (35%, 9/26PC; 9%, 7/80CD; p = 0.001) and systemic (mostly lethargy/tiredness) (27%, 7/26PC; 9%, 7/80CD; p = 0.017) symptoms. CONCLUSIONS: Our findings, add to the growing evidence, that we should reconsider what constitutes alert symptoms for early tubo-ovarian cancer. We need a more nuanced complex of key symptoms which is then evaluated and refined in a prospective trial.


Asunto(s)
Detección Precoz del Cáncer , Neoplasias Ováricas , Femenino , Humanos , Carcinoma Epitelial de Ovario/diagnóstico , Estudios Prospectivos , Neoplasias Ováricas/diagnóstico , Reino Unido/epidemiología
11.
Chem Mater ; 35(21): 9029-9039, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-38027547

RESUMEN

A series of polythiophenes with varying side chain density was synthesized, and their electrical and thermoelectric properties were investigated. Aligned and non-aligned thin films of the polymers were characterized in the neutral and chemically doped states. Optical and diffraction measurements revealed an overall lower order in the thin films with lower side chain density, also confirmed using polarized optical experiments on aligned thin films. However, upon doping the non-aligned films, a sixfold increase in electrical conductivity was observed for the polythiophene with the lowest side chain density compared to poly(3-hexylthiophene) (P3HT). We found that the improvement in conductivity was not due to a larger charge carrier density but an increase in charge carrier mobility after doping with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). On the other hand, doped aligned films did not show the same trend; lower side chain density instead led to a lower conductivity and Seebeck coefficient compared to those for P3HT. This was attributed to the poorer alignment of the polymer thin films with lower side chain density. The study demonstrates that optimizing side chain density is a synthetically simple and effective way to improve electrical conductivity in polythiophene films relevant to thermoelectric applications.

12.
Cell Mol Bioeng ; 16(4): 369-381, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37811005

RESUMEN

Introduction: Pediatric subglottic stenosis (SGS) results from prolonged intubation where scar tissue leads to airway narrowing that requires invasive surgery. We have recently discovered that modulating the laryngotracheal microbiome can prevent SGS. Herein, we show how our patent-pending antimicrobial peptide-eluting endotracheal tube (AMP-ET) effectively modulates the local airway microbiota resulting in reduced inflammation and stenosis resolution. Materials and Methods: We fabricated mouse-sized ETs coated with a polymeric AMP-eluting layer, quantified AMP release over 10 days, and validated bactericidal activity for both planktonic and biofilm-resident bacteria against Staphylococcus aureus and Pseudomonas aeruginosa. Ex vivo testing: we inserted AMP-ETs and ET controls into excised laryngotracheal complexes (LTCs) of C57BL/6 mice and assessed biofilm formation after 24 h. In vivo testing: AMP-ETs and ET controls were inserted in sham or SGS-induced LTCs, which were then implanted subcutaneously in receptor mice, and assessed for immune response and SGS severity after 7 days. Results: We achieved reproducible, linear AMP release at 1.16 µg/day resulting in strong bacterial inhibition in vitro and ex vivo. In vivo, SGS-induced LTCs exhibited a thickened scar tissue typical of stenosis, while the use of AMP-ETs abrogated stenosis. Notably, SGS airways exhibited high infiltration of T cells and macrophages, which was reversed with AMP-ET treatment. This suggests that by modulating the microbiome, AMP-ETs reduce macrophage activation and antigen specific T cell responses resolving stenosis progression. Conclusion: We developed an AMP-ET platform that reduces T cell and macrophage responses and reduces SGS in vivo via airway microbiome modulation. Supplementary Information: The online version contains supplementary material available at 10.1007/s12195-023-00769-9.

13.
Health Technol Assess ; : 1-38, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37843101

RESUMEN

Abstract: Randomised controlled trials are challenging to deliver. There is a constant need to review and refine recruitment and implementation strategies if they are to be completed on time and within budget. We present the strategies adopted in the United Kingdom Collaborative Trial of Ovarian Cancer Screening, one of the largest individually randomised controlled trials in the world. The trial recruited over 202,000 women (2001-5) and delivered over 670,000 annual screens (2001-11) and over 3 million women-years of follow-up (2001-20). Key to the successful completion were the involvement of senior investigators in the day-to-day running of the trial, proactive trial management and willingness to innovate and use technology. Our underlying ethos was that trial participants should always be at the centre of all our processes. We ensured that they were able to contact either the site or the coordinating centre teams for clarifications about their results, for follow-up and for rescheduling of appointments. To facilitate this, we shared personal identifiers (with consent) with both teams and had dedicated reception staff at both site and coordinating centre. Key aspects were a comprehensive online trial management system which included an electronic data capture system (resulting in an almost paperless trial), biobanking, monitoring and project management modules. The automation of algorithms (to ascertain eligibility and classify results and ensuing actions) and processes (scheduling of appointments, printing of letters, etc.) ensured the protocol was closely followed and timelines were met. Significant engagement with participants ensured retention and low rates of complaints. Our solutions to the design, conduct and analyses issues we faced are highly relevant, given the renewed focus on trials for early detection of cancer. Future work: There is a pressing need to increase the evidence base to support decision making about all aspects of trial methodology. Trial registration: ISRCTN-22488978; ClinicalTrials.gov-NCT00058032. Funding: This article presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme as award number 16/46/01. The long-term follow-up UKCTOCS (2015 20) was supported by National Institute for Health and Care Research (NIHR HTA grant 16/46/01), Cancer Research UK, and The Eve Appeal. UKCTOCS (2001-14) was funded by the MRC (G9901012 and G0801228), Cancer Research UK (C1479/A2884), and the UK Department of Health, with additional support from The Eve Appeal. Researchers at UCL were supported by the NIHR UCL Hospitals Biomedical Research Centre and by the MRC Clinical Trials Unit at UCL core funding (MC_UU_00004/09, MC_UU_00004/08, MC_UU_00004/07). The views expressed are those of the authors and not necessarily those of the NHS, the NIHR, or the UK Department of Health and Social Care.


Randomised controlled trials help us decide whether new health-care approaches are better than those in current use. To successfully complete these on time and within budget, there is a constant need to review and revise the procedures used for delivering various aspects such as invitation, enrolment, follow-up of participants, delivery of the new test, data collection, and analysis. We report on the processes used in the United Kingdom Collaborative Trial of Ovarian Cancer Screening, one of the largest such trials. The United Kingdom Collaborative Trial of Ovarian Cancer Screening enrolled over 202,000 women (2001­5), delivered over 670,000 yearly screens (2001­11) and followed all participants until 2020. Key to our successful completion were the involvement of senior investigators in day-to-day running of the trial, a pre-emptive approach to issues, a willingness to innovate, and the use of technology. Our underlying ethos was that trial participants should always be at the centre of all our processes. We ensured that they were able to always contact either their local or the central team for clarifications and rescheduling of appointments. To facilitate this, we shared participant contact details (with consent) with both teams. We built a comprehensive electronic system to manage all aspects of the trial. This included online forms that the teams completed in real time (resulting in an almost paperless trial) and systems to check and manage trial processes and track blood samples. We automated key steps such as checking whether participants were eligible, assigning correct action based on results of screening tests, scheduling appointments and printing letters. As a result, all participants were treated as set out in the trial plan. Our engagement with participants ensured that they continued participating and we had a low rate of complaints. We faced issues with regard to our initial trial design and the way we planned to analyse the data. We feel that our solutions are highly relevant, especially as there is a renewed focus on trials for early detection of cancer.

14.
Small Methods ; 7(11): e2300476, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37661594

RESUMEN

Organic semiconductors are a family of pi-conjugated compounds used in many applications, such as displays, bioelectronics, and thermoelectrics. However, their susceptibility to processing-induced contamination is not well understood. Here, it is shown that many organic electronic devices reported so far may have been unintentionally contaminated, thus affecting their performance, water uptake, and thin film properties. Nuclear magnetic resonance spectroscopy is used to detect and quantify contaminants originating from the glovebox atmosphere and common laboratory consumables used during device fabrication. Importantly, this in-depth understanding of the sources of contamination allows the establishment of clean fabrication protocols, and the fabrication of organic field effect transistors (OFETs) with improved performance and stability. This study highlights the role of unintentional contaminants in organic electronic devices, and demonstrates that certain stringent processing conditions need to be met to avoid scientific misinterpretation, ensure device reproducibility, and facilitate performance stability. The experimental procedures and conditions used herein are typical of those used by many groups in the field of solution-processed organic semiconductors. Therefore, the insights gained into the effects of contamination are likely to be broadly applicable to studies, not just of OFETs, but also of other devices based on these materials.

15.
Lancet Oncol ; 24(9): 1018-1028, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37657461

RESUMEN

BACKGROUND: In UKCTOCS, there was a decrease in the diagnosis of advanced stage tubo-ovarian cancer but no reduction in deaths in the multimodal screening group compared with the no screening group. Therefore, we did exploratory analyses of patients with high-grade serous ovarian cancer to understand the reason for the discrepancy. METHODS: UKCTOCS was a 13-centre randomised controlled trial of screening postmenopausal women from the general population, aged 50-74 years, with intact ovaries. The trial management system randomly allocated (2:1:1) eligible participants (recruited from April 17, 2001, to Sept 29, 2005) in blocks of 32 using computer generated random numbers to no screening or annual screening (multimodal screening or ultrasound screening) until Dec 31, 2011. Follow-up was through national registries until June 30, 2020. An outcome review committee, masked to randomisation group, adjudicated on ovarian cancer diagnosis, histotype, stage, and cause of death. In this study, analyses were intention-to-screen comparisons of women with high-grade serous cancer at censorship (Dec 31, 2014) in multimodal screening versus no screening, using descriptive statistics for stage and treatment endpoints, and the Versatile test for survival from randomisation. This trial is registered with the ISRCTN Registry, 22488978, and ClinicalTrials.gov, NCT00058032. FINDINGS: 202 562 eligible women were recruited (50 625 multimodal screening; 50 623 ultrasound screening; 101 314 no screening). 259 (0·5%) of 50 625 participants in the multimodal screening group and 520 (0·5%) of 101 314 in the no screening group were diagnosed with high-grade serous cancer. In the multimodal screening group compared with the no screening group, fewer were diagnosed with advanced stage disease (195 [75%] of 259 vs 446 [86%] of 520; p=0·0003), more had primary surgery (158 [61%] vs 219 [42%]; p<0·0001), more had zero residual disease following debulking surgery (119 [46%] vs 157 [30%]; p<0·0001), and more received treatment including both surgery and chemotherapy (192 [74%] vs 331 [64%]; p=0·0032). There was no difference in the first-line combination chemotherapy rate (142 [55%] vs 293 [56%]; p=0·69). Median follow-up from randomisation of 779 women with high-grade serous cancer in the multimodal and no screening groups was 9·51 years (IQR 6·04-13·00). At censorship (June 30, 2020), survival from randomisation was longer in women with high-grade serous cancer in the multimodal screening group than in the no screening group with absolute difference in survival of 6·9% (95% CI 0·4-13·0; p=0·042) at 18 years (21% [95% CI 15·6-26·2] vs 14% [95% CI 10·5-17·4]). INTERPRETATION: To our knowledge, this is the first evidence that screening can detect high-grade serous cancer earlier and lead to improved short-term treatment outcomes compared with no screening. The potential survival benefit for women with high-grade serous cancer was small, most likely due to only modest gains in early detection and treatment improvement, and tumour biology. The cumulative results of the trial suggest that surrogate endpoints for disease-specific mortality should not currently be used in screening trials for ovarian cancer. FUNDING: National Institute for Health Research, Medical Research Council, Cancer Research UK, The Eve Appeal.


Asunto(s)
Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/tratamiento farmacológico , Resultado del Tratamiento , Tamizaje Masivo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
16.
Int J Pediatr Otorhinolaryngol ; 172: 111631, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37567085

RESUMEN

INTRODUCTION: Comorbidities such as chronic lung disease and gastroesophageal reflux (GERD), prematurity, and numerous other conditions may impact the success of LTR. Single-center studies are limited in terms of patient numbers and may be underpowered. OBJECTIVES: To analyze the impact of specific comorbidities on the operation-specific and overall surgical success of LTR in a large multicenter cohort and validate a predictive model for surgical success. METHODS: A large retrospective multicenter 10-year review was undertaken to validate the data of a previous single-center study (Wertz et al. Laryngoscope 2020) which identified specific predictive comorbidities which impacted LTR outcomes. A Monte Carlo simulation based on the previous data set suggested that 300-400 cases would be needed to optimize the statistical power of a Bayesian model developed from the single-center data to predict surgical success. An IRB-approved data-sharing agreement was executed for 4 large U.S. CENTERS: A virtual REDCap® data entry form inquired about patient characteristics that best predicted surgical success in the single-center model. These included demographics, surgical approaches, cardiac, airway, genetic, endocrine, musculoskeletal, gastrointestinal, and pulmonary comorbidities; details of the surgical procedures, and results of esophagogastroduodenoscopy (EGD), esophageal pH/impedance and flexible bronchoscopy with bronchioalveolar lavage (BAL) were included. Surgical success defined as successful decannulation or resolution of airway symptoms was recorded as single surgery success and overall success following open surgical revision surgery. Multivariate Bayesian analysis, logistical regression, and Kaplan-Meier analysis were performed. RESULTS: 542 patients were identified, including 165 from the single-center study and an additional 377 patients from the multicenter group. The median age was 36 months at the time of the most recent surgery. 70.9% of the LTRs were double-staged procedures. The overall success rate was 86.4% and operation-specific success rate was 69.2%. The specific comorbidities and aerodigestive test results that impacted success based on univariate analysis included staging, bronchiectasis, pulmonary hypertension, GERD, ASD, PDA, grade of stenosis, advanced levels of stenosis, Trisomy 21, MRSA, prior open surgery at another hospital, and gross appearance on EGD. Bayesian model averaging with backward selection was used to validate and refine a predictive model for surgical success with favorable receiver operating curve characteristics - AUC values of 0.827 for single surgery success and 0.797 for overall success. DISCUSSION: With over 500 patients reviewed, this was the largest multicenter study of LTR to date, which elucidated the impact of comorbidities on success with LTR and was able to improve upon the predictive modeling based on single-center data. Patient factors are most critical in the outcome of LTR. Stage and levels of stenosis, as well as pulmonary and GI conditions most strongly impact the likelihood of success. Future prospective case-control studies will be performed to further optimize the current model for outcome prediction and patient management.


Asunto(s)
Reflujo Gastroesofágico , Laringoestenosis , Estenosis Traqueal , Humanos , Preescolar , Laringoestenosis/complicaciones , Laringoestenosis/epidemiología , Laringoestenosis/cirugía , Estenosis Traqueal/complicaciones , Estenosis Traqueal/epidemiología , Estenosis Traqueal/cirugía , Constricción Patológica , Teorema de Bayes , Estudios Retrospectivos , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/epidemiología , Resultado del Tratamiento
17.
Sci Adv ; 9(22): eadg8659, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37267357

RESUMEN

Organic thin-film transistors (OTFTs) with ideal behavior are highly desired, because nonideal devices may overestimate the intrinsic property and yield inferior performance in applications. In reality, most polymer OTFTs reported in the literature do not exhibit ideal characteristics. Supported by a structure-property relationship study of several low-disorder conjugated polymers, here, we present an empirical selection rule for polymer candidates for textbook-like OTFTs with high reliability factors (100% for ideal transistors). The successful candidates should have low energetic disorder along their backbones and form thin films with spatially uniform energetic landscapes. We demonstrate that these requirements are satisfied in the semicrystalline polymer PffBT4T-2DT, which exhibits a reliability factor (~100%) that is exceptionally high for polymer devices, rendering it an ideal candidate for OTFT applications. Our findings broaden the selection of polymer semiconductors with textbook-like OTFT characteristics and would shed light upon the molecular design criteria for next-generation polymer semiconductors.

18.
Cancers (Basel) ; 15(9)2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37174087

RESUMEN

Limited therapies exist for neurofibromatosis type 1 (NF1)-associated plexiform neurofibroma (PN). For this reason, the activity of vinblastine (VBL) and methotrexate (MTX) was evaluated in children and young adults with NF1 and PN. Patients ≤ 25 years of age with progressive and/or inoperable NF1-PN received VBL 6 mg/m2 and MTX 30 mg/m2 weekly for 26 weeks, followed by every 2 weeks for 26 weeks. Objective response rate was the primary endpoint. Of 25 participants enrolled, 23 were evaluable. The median age of participants was 6.6 years (range 0.3-20.7). The most frequent toxicities were neutropenia and elevation of transaminases. On two-dimensional (2D) imaging, 20 participants (87%) had stable tumor, with a median time to progression of 41.5 months (95% confidence interval 16.9, 64.9). Two of eight participants (25%) with airway involvement demonstrated functional improvements including decreased positive pressure requirements and apnea-hypopnea index. A post hoc three-dimensional (3D) analysis of PN volumes was completed on 15 participants with amenable imaging; 7 participants (46%) had progressive disease on or by the end of therapy. VBL/MTX was well-tolerated but did not result in objective volumetric response. Furthermore, 3D volumetric analysis highlighted the lack of sensitivity of 2D imaging for PN response evaluation.

19.
Health Technol Assess ; : 1-81, 2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37183782

RESUMEN

Background: Ovarian and tubal cancers are lethal gynaecological cancers, with over 50% of the patients diagnosed at advanced stage. Trial design: Randomised controlled trial involving 27 primary care trusts adjacent to 13 trial centres based at NHS Trusts in England, Wales and Northern Ireland. Methods: Postmenopausal average-risk women, aged 50-74, with intact ovaries and no previous ovarian or current non-ovarian cancer. Interventions: One of two annual screening strategies: (1) multimodal screening (MMS) using a longitudinal CA125 algorithm with repeat CA125 testing and transvaginal scan (TVS) as second line test (2) ultrasound screening (USS) using TVS alone with repeat scan to confirm any abnormality. The control (C) group had no screening. Follow-up was through linkage to national registries, postal follow-up questionnaires and direct communication with trial centres and participants. Objective: To assess comprehensively risks and benefits of ovarian cancer screening in the general population. Outcome: Primary outcome was death due to ovarian or tubal cancer as assigned by an independent outcomes review committee. Secondary outcomes included incidence and stage at diagnosis of ovarian and tubal cancer, compliance, performance characteristics, harms and cost-effectiveness of the two screening strategies and a bioresource for future research. Randomisation: The trial management system confirmed eligibility and randomly allocated participants using computer-generated random numbers to MMS, USS and C groups in a 1:1:2 ratio. Blinding: Investigators and participants were unblinded and outcomes review committee was masked to randomisation group. Analyses: Primary analyses were by intention to screen, comparing separately MMS and USS with C using the Versatile test. Results: 1,243,282 women were invited and 205,090 attended for recruitment between April 2001 and September 2005. Randomised: 202,638 women: 50,640 MMS, 50,639 USS and 101,359 C group. Numbers analysed for primary outcome: 202,562 (>99.9%): 50,625 (>99.9%) MMS, 50,623 (>99.9%) USS, and 101,314 (>99.9%) C group. Outcome: Women in MMS and USS groups underwent 345,570 and 327,775 annual screens between randomisation and 31 December 2011. At median follow-up of 16.3 (IQR 15.1-17.3) years, 2055 women developed ovarian or tubal cancer: 522 (1.0% of 50,625) MMS, 517 (1.0% of 50,623) USS, and 1016 (1.0% of 101314) in C group. Compared to the C group, in the MMS group, the incidence of Stage I/II disease was 39.2% (95% CI 16.1 to 66.9) higher and stage III/IV 10.2% (95% CI -21.3 to 2.4) lower. There was no difference in stage in the USS group. 1206 women died of the disease: 296 (0.6%) MMS, 291 (0.6%) USS, and 619 (0.6%) C group. There was no significant reduction in ovarian and tubal cancer deaths in either MMS (p = 0.580) or USS (p = 0.360) groups compared to the C group. Overall compliance with annual screening episode was 80.8% (345,570/420,047) in the MMS and 78.0% (327,775/420,047) in the USS group. For ovarian and tubal cancers diagnosed within one year of the last test in a screening episode, in the MMS group, the sensitivity, specificity and positive predictive values were 83.8% (95% CI 78.7 to 88.1), 99.8% (95% CI 99.8 to 99.9), and 28.8% (95% CI 25.5 to 32.2) and in the USS group, 72.2% (95% CI 65.9 to 78.0), 99.5% (95% CI 99.5 to 99.5), and 9.1% (95% CI 7.8 to 10.5) respectively. The final within-trial cost-effectiveness analysis was not undertaken as there was no mortality reduction. A bioresource (UKCTOCS Longitudinal Women's Cohort) of longitudinal outcome data and over 0.5 million serum samples including serial annual samples in women in the MMS group was established and to date has been used in many new studies, mainly focused on early detection of cancer. Harms: Both screening tests (venepuncture and TVS) were associated with minor complications with low (8.6/100,000 screens MMS; 18.6/100,000 screens USS) complication rates. Screening itself did not cause anxiety unless more intense repeat testing was required following abnormal screens. In the MMS group, for each screen-detected ovarian or tubal cancer, an additional 2.3 (489 false positives; 212 cancers) women in the MMS group had unnecessary false-positive (benign adnexal pathology or normal adnexa) surgery. Overall, 14 (489/345,572 annual screens) underwent unnecessary surgery per 10,000 screens. In the USS group, for each screen-detected ovarian or tubal cancer, an additional 10 (1630 false positives; 164 cancers) underwent unnecessary false-positive surgery. Overall, 50 (1630/327,775 annual screens) women underwent unnecessary surgery per 10,000 screens. Conclusions: Population screening for ovarian and tubal cancer for average-risk women using these strategies should not be undertaken. Decreased incidence of Stage III/IV cancers during multimodal screening did not translate to mortality reduction. Researchers should be cautious about using early stage as a surrogate outcome in screening trials. Meanwhile the bioresource provides a unique opportunity to evaluate early cancer detection tests. Funding: Long-term follow-up UKCTOCS (2015-2020) - National Institute for Health and Care Research (NIHR HTA grant 16/46/01), Cancer Research UK, and The Eve Appeal. UKCTOCS (2001-2014) - Medical Research Council (MRC) (G9901012/G0801228), Cancer Research UK (C1479/A2884), and the UK Department of Health, with additional support from The Eve Appeal. Researchers at UCL were supported by the NIHR UCL Hospitals Biomedical Research Centre and by MRC Clinical Trials Unit at UCL core funding (MR_UU_12023).


Text: Most women with ovarian cancer are diagnosed after the disease has spread widely (advanced stage ­ III and IV) and more than half die within 5 years. We wanted to find out if testing women without symptoms could pick up ovarian cancer at an earlier stage before it has spread beyond the ovaries and tubes and reduce deaths. We also wanted to assess the risks and benefits of such screening. Text: We invited over 1.2 million women living near 13 centres in England, Wales and Northern Ireland. Of them, 202,638 joined the trial. All women were between 50 and 74 and were no longer having periods. They had never been diagnosed with ovarian cancer or were not having treatment for any other cancer. They did not have many relatives with ovarian or breast cancer. The volunteers were placed into one of three groups at random. List: 1. The blood test group contained 50,640 women who had yearly CA125 blood tests. If these showed a moderate or high chance of ovarian cancer, they had repeat CA125 tests and a scan. List: 2. The scan group contained 50,639 women who had yearly internal scans of their ovaries and tubes which were repeated if they showed an abnormality. List: 3. The no-screening group contained 101,359 women. Text: Those in the blood and scan groups had screening every year until December 2011. We sent all women health questionnaires and also, with their permission, received information about them from the national cancer and death registries till mid-2020. Text: Women in the screened groups had an average of eight years of screening. We followed them for approximately 16 years after they had joined the trial. During this period, 2055 women were diagnosed with ovarian and tubal cancer. It was about 1 in 100 women (1%) in all three groups. List: • 522 of 50,625 in the blood group. List: • 517 of 50,623 in the scan group. List: • 1016 of 101,314 in the no-screening group. Text: More women were diagnosed with early-stage cancer and fewer were diagnosed with advanced cancer in the blood group compared to the no-screening group. There was no difference in the number diagnosed with early or advanced disease between the scan and no-screening group. Despite this difference, the number of women in each group who died from ovarian and tubal cancer was similar in all three groups: 296 of 50,625 (0.6%) in the blood group, 291 of 50,623 (0.6%) in the scan group and 619 of 101,314 (0.6%) in the no-screening group. Other results showed. List: • Overall, 81% women in the blood group and 78% in the scan group attended all of their annual screening appointments. List: • In the blood group, screening detected 84% of ovarian and tubal cancers diagnosed within one year of the test and correctly classified as normal 99.8% of women who did not have ovarian and tubal cancer. List: • In the scan group, screening detected 72% of ovarian and tubal cancers diagnosed within one year of the last test and correctly classified 99.5% of those who did not have ovarian and tubal cancer. List: • Both screening tests were associated with minor complications. List: • While screening did not increase anxiety, there was slightly increased worry in women who were asked to return for more intense repeat testing. List: • Both screening methods picked up changes that were in fact not ovarian cancer. This meant that women had unnecessary surgery together with the worry and risk of complications that go with it. List: ◦ In the blood group 14 women had unnecessary surgery for every 10,000 women screened annually. This means that for each woman found to have ovarian cancer, an additional 2 women had unnecessary surgery. List: ◦ In the scan group 50 women had unnecessary surgery for every 10,000 women screened annually. This means that for each woman found to have ovarian cancer, an additional 10 women had unnecessary surgery. List: • A biobank with all the donated data and over 0.5 million serum samples, including yearly samples from women in the blood group, was built and continues to be used in many new studies, mainly focused on early detection of cancer. Text: Screening using the CA125 blood test or transvaginal ultrasound scan to test for ovarian cancer did not save lives. Additionally, it was associated with some harm. Therefore, an ovarian cancer screening programme for most women cannot be currently recommended. The trial also showed for the first time that ovarian cancer can be detected earlier through screening. However, for screening to save lives, the test needs to pick up many more women earlier in the course of the disease so that available treatments are effective. The biobank provides an opportunity for scientists to see if newer tests for cancer can detect the disease earlier.

20.
Commun Med (Lond) ; 3(1): 10, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36670203

RESUMEN

BACKGROUND: Earlier detection of pancreatic ductal adenocarcinoma (PDAC) is key to improving patient outcomes, as it is mostly detected at advanced stages which are associated with poor survival. Developing non-invasive blood tests for early detection would be an important breakthrough. METHODS: The primary objective of the work presented here is to use a dataset that is prospectively collected, to quantify a set of cancer-associated proteins and construct multi-marker models with the capacity to predict PDAC years before diagnosis. The data used is part of a nested case-control study within the UK Collaborative Trial of Ovarian Cancer Screening and is comprised of 218 samples, collected from a total of 143 post-menopausal women who were diagnosed with pancreatic cancer within 70 months after sample collection, and 249 matched non-cancer controls. We develop a stacked ensemble modelling technique to achieve robustness in predictions and, therefore, improve performance in newly collected datasets. RESULTS: Here we show that with ensemble learning we can predict PDAC status with an AUC of 0.91 (95% CI 0.75-1.0), sensitivity of 92% (95% CI 0.54-1.0) at 90% specificity, up to 1 year prior to diagnosis, and at an AUC of 0.85 (95% CI 0.74-0.93) up to 2 years prior to diagnosis (sensitivity of 61%, 95% CI 0.17-0.83, at 90% specificity). CONCLUSIONS: The ensemble modelling strategy explored here outperforms considerably biomarker combinations cited in the literature. Further developments in the selection of classifiers balancing performance and heterogeneity should further enhance the predictive capacity of the method.


Pancreatic cancers are most frequently detected at an advanced stage. This limits treatment options and contributes to the dismal survival rates currently recorded. The development of new tests that could improve detection of early-stage disease is fundamental to improve outcomes. Here, we use advanced data analysis techniques to devise an early detection test for pancreatic cancer. We use data on markers in the blood from people enrolled on a screening trial. Our test correctly identifies as positive for pancreatic cancer 91% of the time up to 1 year prior to diagnosis, and 78% of the time up to 2 years prior to diagnosis. These results surpass previously reported tests and should encourage further evaluation of the test in different populations, to see whether it should be adopted in the clinic.

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