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1.
Trop Med Infect Dis ; 9(7)2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39058201

RESUMO

The elimination of schistosomiasis as a public health problem by 2030 is one of the main goals put forth in the World Health Organization's roadmap for neglected tropical diseases. This study aimed to compare different sampling approaches to guide mapping and preventive chemotherapy. A cross-sectional parasitological survey was conducted from August to September 2022 in the health districts of Biankouma, Ouaninou, and Touba in the western part of Côte d'Ivoire. The prevalence and intensity of Schistosoma mansoni infection were assessed in children aged 5-14 years using three sampling approaches. The first approach involved a random selection of 50% of the villages in the health districts. The second approach involved a random selection of half of the villages selected in approach 1, thus constituting 25% of the villages in the health district. The third approach consisted of randomly selecting 15 villages from villages selected by approach 2 in each health district. The overall prevalence of S. mansoni was 23.5% (95% confidence interval (CI): 19.9-27.6%), 21.6% (95% CI: 17.1-26.8%), and 18.3% (95% CI: 11.9-27.1%) with the first, second, and third approach, respectively. The respective geometric mean S. mansoni infection intensity was 117.9 eggs per gram of stool (EPG) (95% CI: 109.3-127.3 EPG), 104.6 EPG (95% CI: 93.8-116.6 EPG), and 94.6 EPG (95% CI 79.5-112.7 EPG). We conclude that, although randomly sampling up to 50% of villages in a health district provides more precise population-based prevalence and intensity measures of S. mansoni, randomly selecting only 15 villages in a district characterized by low heterogeneity provides reasonable estimates and is less costly.

2.
J Gynecol Obstet Hum Reprod ; 53(8): 102805, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38844086

RESUMO

OBJECTIVES: To evaluate whether the quality scores validated for second-trimester ultrasound scan can be used for third-trimester ultrasound scan. METHODS: Prospective multicenter ancillary study using data from the RECRET study. Nulliparous women, with no reported history, with second- and third-trimester ultrasound examinations performed by the same ultrasonographer and using the same ultrasound machine were recruited. The global score and the individual score of each ultrasound image were compared between second- and third-trimester ultrasound scan. The sample size was calculated for a non-inferiority (one-sided) paired Student t test. RESULTS: 103 women with 1606 anonymized ultrasound images were included. The median term at second- and third-trimester ultrasound scan was 22.2 weeks gestation (22.0-22.7) and 31.6 weeks gestation (30.7-34.7), respectively. The mean global score of ultrasound images was comparable between the second- and the third-trimester ultrasound examination (32.37 ± 2.62 versus 31.80 ± 3.27, p = 0.13). Means scores for each biometric parameters i.e. head circumference, abdominal circumference, and femur diaphysis length were comparable. The scores for the four-chamber view (5.11 ± 0.91 versus 5.36 ± 0.75, p = 0.02) and the spine (4.18 ± 1.17 versus 5.22 ± 1.02, p < 0.001) were significantly lower in the third trimester compared to the second trimester. The score for the kidney image was significantly higher for third trimester images compared to second trimester images (4.73 ± 0.51 versus 4.32 ± 0.67, p < 0.001. CONCLUSIONS: Biometrics parameters quality scores images previously validated for the second trimester ultrasound scan can be also used for the third trimester scan. However, anatomical quality scores images performances may vary between the second and the third trimester scan.

3.
J Clin Med ; 13(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38610825

RESUMO

Background: Heart rate variability (HRV) is an established, non-invasive parameter for the assessment of cardiac autonomic nervous activity and the health status in general cardiology. However, there are few studies on HRV in adults with congenital heart defects (CHDs). The aim of the present study was to evaluate the use of long-term continuous HRV measurement for the assessment of global health status in adults with cyanotic CHD. Methods: This prospective study included 45 adults (40% female, mean age = 35.2 ± 9.2 [range: 19-58] years) after cardiac surgical repair. HRV parameters were calculated from continuous 24 h measurements using a Bittium Faros 180 sensor (Bittium Corp., Oulu, Finland). Results: Postoperative patients with transposition of the great arteries (TGA) (n = 18) achieved significantly higher values of standard deviation of NN intervals (SDNN) (175.4 ± 59.9 ms vs. 133.5 ± 40.6 ms; p = 0.013) compared with patients with other conotruncal anomalies (n = 22). Comparing patients with TGA after a Senning-Brom or Mustard operation (n = 13) with all other heart surgery patients (n = 32), significantly higher HRV parameters were found after atrial switch (root mean square of successive RR interval differences: 53.6 ± 20.7 ms vs. 38.4 ± 18.3 ms; p = 0.019; SDNN: 183.5 ± 58.4 ms vs. 136.3 ± 45.3 ms; p = 0.006). A higher SDNN was also measured after Senning-Brom or Mustard operations than after a Rastelli operations (n = 2) (SDNN: 183.5 ± 58.4 ms vs. 84.5 ± 5.2 ms; p = 0.037). When comparing atrial switch operations (n = 3) with Rastelli operations, the SDNN value was significantly shorter in the Rastelli group (p = 0.004). Conclusions: Our results suggest that continuous HRV monitoring may serve as a marker of cardiac autonomic dysfunction in adults with cyanotic CHD after surgical repair. Impaired cardiac autonomic nervous activity may be associated with an increased risk of adverse reactions in patients with repaired CHD. Therefore, a longitudinal assessment of HRV patterns and trends may provide a deeper insight into dynamic changes in their autonomic regulation and disease progression, lifestyle changes, or treatments. As each person has individual variability in heart rate, HRV may be useful in assessing intra-individual disease progression and may help to improve personalized medicine. Further studies are needed to better understand the underlying mechanisms and to explore the full potential of HRV analysis to optimize medical care for ACHDs.

4.
BMC Cardiovasc Disord ; 24(1): 181, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532336

RESUMO

BACKGROUND: Adults with congenital heart defects (ACHD) globally constitute a notably medically underserved patient population. Despite therapeutic advancements, these individuals often confront substantial physical and psychosocial residua or sequelae, requiring specialized, integrative cardiological care throughout their lifespan. Heart failure (HF) is a critical challenge in this population, markedly impacting morbidity and mortality. AIMS: The primary aim of this study is to establish a comprehensive, prospective registry to enhance understanding and management of HF in ACHD. Named PATHFINDER-CHD, this registry aims to establish foundational data for treatment strategies as well as the development of rehabilitative, prehabilitative, preventive, and health-promoting interventions, ultimately aiming to mitigate the elevated morbidity and mortality rates associated with congenital heart defects (CHD). METHODS: This multicenter survey will be conducted across various German university facilities with expertise in ACHD. Data collection will encompass real-world treatment scenarios and clinical trajectories in ACHD with manifest HF or at risk for its development, including those undergoing medical or interventional cardiac therapies, cardiac surgery, inclusive of pacemaker or ICD implantation, resynchronization therapy, assist devices, and those on solid organ transplantation. DESIGN: The study adopts an observational, exploratory design, prospectively gathering data from participating centers, with a focus on patient management and outcomes. The study is non-confirmatory, aiming to accumulate a broad spectrum of data to inform future hypotheses and studies. PROCESSES: Regular follow-ups will be conducted, systematically collecting data during routine clinical visits or hospital admissions, encompassing alterations in therapy or CHD-related complications, with visit schedules tailored to individual clinical needs. ASSESSMENTS: Baseline assessments and regular follow-ups will entail comprehensive assessments of medical history, ongoing treatments, and outcomes, with a focus on HF symptoms, cardiac function, and overall health status. DISCUSSION OF THE DESIGN: The design of the PATHFINDER-CHD Registry is tailored to capture a wide range of data, prioritizing real-world HF management in ACHD. Its prospective nature facilitates longitudinal data acquisition, pivotal for comprehending for disease progression and treatment impacts. CONCLUSION: The PATHFINDER-CHD Registry is poised to offer valuable insights into HF management in ACHD, bridging current knowledge gaps, enhancing patient care, and shaping future research endeavors in this domain.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas , Insuficiência Cardíaca , Adulto , Humanos , Cardiopatias Congênitas/diagnóstico , Progressão da Doença , Sistema de Registros , Função Ventricular
5.
J Chem Inf Model ; 64(7): 2331-2344, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37642660

RESUMO

Federated multipartner machine learning has been touted as an appealing and efficient method to increase the effective training data volume and thereby the predictivity of models, particularly when the generation of training data is resource-intensive. In the landmark MELLODDY project, indeed, each of ten pharmaceutical companies realized aggregated improvements on its own classification or regression models through federated learning. To this end, they leveraged a novel implementation extending multitask learning across partners, on a platform audited for privacy and security. The experiments involved an unprecedented cross-pharma data set of 2.6+ billion confidential experimental activity data points, documenting 21+ million physical small molecules and 40+ thousand assays in on-target and secondary pharmacodynamics and pharmacokinetics. Appropriate complementary metrics were developed to evaluate the predictive performance in the federated setting. In addition to predictive performance increases in labeled space, the results point toward an extended applicability domain in federated learning. Increases in collective training data volume, including by means of auxiliary data resulting from single concentration high-throughput and imaging assays, continued to boost predictive performance, albeit with a saturating return. Markedly higher improvements were observed for the pharmacokinetics and safety panel assay-based task subsets.


Assuntos
Benchmarking , Relação Quantitativa Estrutura-Atividade , Bioensaio , Aprendizado de Máquina
6.
J Clin Med ; 12(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37892598

RESUMO

Malignant cardiac tumors of the heart are extremely rare and may present tremendous diagnostic and therapeutic challenges. These tumors are able to infiltrate the heart and metastasize systemically. Early detection is often elusive as the clinical presentation is highly variable, posing significant diagnostic and therapeutic difficulties. Despite a multidisciplinary approach, the prognosis for patients with malignant cardiac tumors remains guarded. Early diagnosis and a multidisciplinary approach involving cardiac surgeons, oncologists and critical care specialists are crucial in the management of this disease. Further research is needed to better understand the pathomechanisms of tumor-related complications and to develop effective treatment strategies to improve patient outcomes. The rare case of a 78-year-old woman with left atrial tumor requiring emergency surgery for acutely developing mitral valve obstruction is presented. Pathology confirmed an undifferentiated pleomorphic sarcoma. This patient tragically did not survive, highlighting the difficulties of managing such a rare and deceptive heart disease.

7.
J Clin Med ; 12(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37834969

RESUMO

Concomitant LAA occlusion has been shown to be an effective and safe treatment for patients with atrial fibrillation during cardiac surgery to prevent embolic stroke. Minimally invasive procedures are challenging due to restricted access to and visibility of the surgical site. Also, aortic endoclamping has been developed as an alternative surgical approach to exoclamping. The aim of this article is to demonstrate the method of beating heart LAA occlusion with the Atriclip® (AtriCure, Mason, OH, USA) device during minimally invasive mitral valve surgery while using the endoclamping alternative for aortic cross-clamping.

8.
Pathogens ; 12(9)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37764938

RESUMO

Infective endocarditis (IE) is still a life-threatening disease with high morbidity and mortality. While usually caused by a single bacterium, poly-microbial infective endocarditis (IE) is rare. Here, we report a (blood-culture-negative) dual pathogen mitral valve IE caused by Coxiella burnetii and Streptococcus gordonii: A 53-year-old woman was presented to an internal medicine department with abdominal pain for further evaluation. Within the diagnostic work up, transthoracic echocardiography (TTE) revealed an irregularly shaped echogenic mass (5 × 13 mm) adherent to the edge of the posterior mitral valve leaflet and protruding into the left atrium. As infected endocarditis was suspected, blood cultures were initially obtained, but they remained negative. Chronic Q fever infection was diagnosed using serologic testing. After the occurrence of cerebral thromboembolic events, the patient was admitted for mitral valve surgery. Intraoperatively, a massively destructed mitral valve with adhering vegetations was noted. Examination of the mitral valve by broad-range bacterial polymerase chain reaction (PCR) and amplicon sequencing confirmed Coxiella burnetii infection and yielded Streptococcus gordonii as the second pathogen. Based on the detailed diagnosis, appropriate antibiotic therapy of both pathogens was initiated, and the patient could be discharged uneventfully on the 11th postoperative day after a successful minimal-invasive mitral valve replacement.

9.
Cancer Radiother ; 27(6-7): 643-647, 2023 Sep.
Artigo em Francês | MEDLINE | ID: mdl-37516639

RESUMO

Radiation-induced toxicity of the digestive tract is a major clinical concern as many cancer survivors have received radiotherapy for tumours of the abdominopelvic area. The coordination and orchestration of a tissue's response to stress depend not only on the phenotype of the cells that make up the tissue but also on cell-cell interactions. The digestive system, i.e., the intestine/colon/rectum, is made up of a range of different cell populations: epithelial cells, stromal cells, i.e. endothelial cells and mesenchymal lineages, immune cells and nerve cells. Moreover, each of these populations is heterogeneous and presents very significant plasticity and differentiation states. The pathogenesis of radiation-induced digestive lesions is an integrated process that involves multiple cellular compartments interacting in a complex sequence of events. Understanding all the cellular events and communication networks that contribute to the tissue's response to stress is therefore a major conceptual and methodological scientific challenge. The study of heterogeneous populations of cells in a tissue is now possible thanks to "single cell' RNA sequencing and spatial transcriptomics techniques, which enable a comprehensive study of the transcriptomic profiles of individual cells in an integrated system. In addition, the mathematical and bioinformatics tools that are now available for the large-scale analysis of data allow the inference of cell-cell communication networks. Such approaches have become possible through advances in bioinformatics algorithms for the analysis and deciphering of interaction networks. Interactions influence the tissue regeneration process through expression of various molecules, including metabolites, integrins, junction proteins, ligands, receptors and proteins secreted into the extracellular space. The vascular network is viewed as a key player in the progression of digestive lesions, which are characterised by infiltration of a range of immune cells. A better characterisation of endothelium/immune cell interactions in suitable preclinical models, as well as in humans, may help to identify some promising therapeutic targets for the prediction, prevention or treatment of digestive toxicity after radiotherapy.


Assuntos
Neoplasias , Lesões por Radiação , Humanos , Células Endoteliais , Endotélio Vascular/patologia , Neoplasias/patologia , Lesões por Radiação/patologia , Fenótipo
10.
Annu Rev Biochem ; 92: 145-173, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37068770

RESUMO

Over the past decade, mRNA modifications have emerged as important regulators of gene expression control in cells. Fueled in large part by the development of tools for detecting RNA modifications transcriptome wide, researchers have uncovered a diverse epitranscriptome that serves as an additional layer of gene regulation beyond simple RNA sequence. Here, we review the proteins that write, read, and erase these marks, with a particular focus on the most abundant internal modification, N6-methyladenosine (m6A). We first describe the discovery of the key enzymes that deposit and remove m6A and other modifications and discuss how our understanding of these proteins has shaped our views of modification dynamics. We then review current models for the function of m6A reader proteins and how our knowledge of these proteins has evolved. Finally, we highlight important future directions for the field and discuss key questions that remain unanswered.


Assuntos
Adenosina , Regulação da Expressão Gênica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Adenosina/genética , Adenosina/metabolismo , Proteínas/genética , Proteínas/metabolismo , Transcriptoma
11.
J Clin Med ; 12(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36769805

RESUMO

(1) Background: Systemic mastocytosis is a rare, non-curable disease with potential life-threatening complications in patients receiving cardiac surgery. (2) Methods: This systematic review of the literature was prompted by the case of a life-threatening anaphylactic reaction during cardiac surgery related to systemic mastocytosis. The search of all types of studies, using several databases (Pubmed, Scopus and Web of Science), was conducted through September 2022 to identify the relevant studies. (3) Results: Twelve studies were included describing cases of patients undergoing cardiac surgery who were diagnosed with systemic mastocytosis. An adverse effect, namely anaphylaxis, has happened in three cases. Different strategies of premedication, intraoperative and postoperative management were used. In our case, the patient was admitted for elective biological aortic valve replacement due to severe aortic stenosis. Intraoperatively, the patient developed an anaphylactic shock during the administration of protamine after separation from the cardiopulmonary bypass. This anaphylaxis reaction was a complication of the pre-existing systemic mastocytosis and could be successfully managed by the administration of epinephrine, antihistamines and corticosteroids. (4) Conclusions: This systematic literature search and case report highlight the importance of careful preoperative planning, as well as coordination between cardiac surgeons, anesthesiologists and hemato-oncological specialists, in patients with rare but complication-prone diseases such as systemic mastocytosis.

12.
J Cardiothorac Surg ; 18(1): 60, 2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36739433

RESUMO

BACKGROUND: Pericardial tamponade (PT) early after cardiac surgery is a challenging clinical entity, not infrequently misrecognized and often only detected late in its course. Because the clinical signs of pericardial tamponade can be very unspecific, a high degree of initial suspicion is required to establish the diagnosis. In addition to clinical examination the deployment of imaging techniques is almost always mandatory in order to avoid delays in diagnosis and to initiate any necessary interventions, such as pericardiocentesis or direct cardiac surgical interventions. After a brief overview of how knowledge of PT has developed throughout history, we report on an atypical life-threatening cardiac tamponade after cardiac surgery. A 74-year-old woman was admitted for elective biological aortic valve replacement and aorto-coronary-bypass grafting (left internal mammary artery to left anterior descending artery, single vein graft to right coronary artery). On the 10th postoperative day, the patient unexpectedly deteriorated. She rapidly developed epigastric pain radiating to the left upper abdomen, and features of low peripheral perfusion and shock. There were no clear signs of pericardial tamponade either clinically or echocardiographically. Therefore, for further differential diagnosis, a contrast-enhanced computed tomography scan was performed under clinical suspicion of acute abdomen. Unexpectedly, active bleeding distally from the right coronary anastomosis was revealed. While the patient was prepared for operative revision, she needed cardiopulmonary resuscitation, which was successful. Intraoperatively, the source of bleeding was located and surgically relieved. The subsequent postoperative course was uneventful. CONCLUSIONS: In the first days after cardiac surgery, the occurrence of life-threatening situations, such as cardiac tamponade, must be expected. Especially if the symptoms are atypical, the entire diagnostic armamentarium must be applied to identify the origin of the complaints, which may be cardiac, but also non-cardiac. CENTRAL MESSAGE: A high level of suspicion, immediate diagnostic confirmation, and rapid treatment are required to recognize and successfully treat such an emergency (Fig. 5). PERSPECTIVE: Pericardial tamponade should always be considered as a complication of cardiac surgery, even when symptoms are atypical. The full range of diagnostic tools must be used to identify the origin of the complaints, which may be cardiac, but also non-cardiac (Fig. 5).


Assuntos
Procedimentos Cirúrgicos Cardíacos , Tamponamento Cardíaco , Feminino , Humanos , Idoso , Tamponamento Cardíaco/diagnóstico , Tamponamento Cardíaco/etiologia , Tamponamento Cardíaco/cirurgia , Pericardiocentese/efeitos adversos , Coração , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Tomografia Computadorizada por Raios X/efeitos adversos
13.
ACS Appl Mater Interfaces ; 15(2): 3680-3688, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36603855

RESUMO

Electronic waste is a growing challenge which needs to be addressed through the integration of high-performance sustainable materials. Green dielectric polymers such as poly(vinyl alcohol) (PVA) have favorable electrical properties but are challenging to integrate into thin film electronics due to their physical properties. For example, PVA suffers from poor film formation and is hygroscopic. Bilayer dielectrics with interfacial cross-linking can enable the use of high-performance PVA with favorable surface chemistry by using a hydrophobic poly(caprolactone) (PCL) layer. In this study, we developed a benzodioxinone-terminated PCL layer, which can be UV cross-linked to the hydroxy groups of the PVA dielectric. This air-stable UV-cross-linking PCL dielectric was able to effectively cross-link with PVA, leading to high-performance capacitors and single-walled carbon nanotube-based thin film transistors. This UV cross-linking PCL dielectric led to significant improvements in shelf-life, ease of processing, and similar device performance compared to our previously reported thermally cross-linking PCL layer. The UV cross-linking at the interface between these bilayers can allow for the integration of high-speed roll-to-roll processing, which enables low-cost, sustainable, and high-performance electronics.

14.
Support Care Cancer ; 30(12): 10223-10231, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36283985

RESUMO

PURPOSE: The objective of this study is to evaluate predictors for attendance in a home-based adapted physical activity (APA) program for women with breast cancer during chemotherapy and radiotherapy treatment. METHODS: This retrospective study was based on two prospective studies (SAPA and APAC), including a total of 73 patients with localized breast cancer during their treatment period. The same APA program lasting 27 weeks was proposed and registered. It consisted of three physical activity sessions (two aerobic and one strength training) per week. The predictors (age, height, body weight, body mass index (BMI), VO2peak, 6-min walking test distance (6MWT), fatigue (MFI), quality of life (EORTC-QLQ), anxiety and depression (HADS), and previous physical activity (IPAQ)) were evaluated before the APA program. RESULTS: According to the multivariate regression analysis, the baseline 6MWT distance and quality of life were predictive of good attendance in the APA program. The univariate analysis showed that initial VO2peak, body weight, BMI, and fatigue influenced attendance in the APA program. CONCLUSIONS: This study helps to better understand the profile of patients who would be participative or non-participative in an APA program. 6MWT distance and quality of life accounted for 19% of attendance in an APA program before the start of treatment. These correlations between the initial predictors of women with breast cancer and their attendance in the APA program during their treatment period make it possible to adapt physical activity professional practices to these patients.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Qualidade de Vida , Estudos Prospectivos , Estudos Retrospectivos , Exercício Físico , Fadiga/etiologia , Peso Corporal , Terapia por Exercício
15.
Genes Dev ; 36(17-18): 1002-1015, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36302554

RESUMO

RNA-binding proteins (RBPs) regulate nearly every aspect of mRNA processing and are important regulators of gene expression in cells. However, current methods for transcriptome-wide identification of RBP targets are limited, since they examine only a single RBP at a time and do not provide information on the individual RNA molecules that are bound by a given RBP. Here, we overcome these limitations by developing TRIBE-STAMP, an approach for single-molecule detection of the target RNAs of two RNA binding proteins simultaneously in cells. We applied TRIBE-STAMP to the cytoplasmic m6A reader proteins YTHDF1, YTHDF2, and YTHDF3 and discovered that individual mRNA molecules can be bound by more than one YTHDF protein throughout their lifetime, providing new insights into the function of YTHDF proteins in cells. TRIBE-STAMP is a highly versatile approach that enables single-molecule analysis of the targets of RBP pairs simultaneously in the same cells.


Assuntos
Proteínas de Ligação a RNA , RNA , Proteínas de Ligação a RNA/metabolismo , RNA/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma , Processamento Pós-Transcricional do RNA
16.
ACS Appl Mater Interfaces ; 14(35): 40361-40370, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-35998386

RESUMO

The widespread realization of wearable electronics requires printable active materials capable of operating at low voltages. Polymerized ionic liquid (PIL) block copolymers exhibit a thickness-independent double-layer capacitance that makes them a promising gating medium for the development of organic thin-film transistors (OTFTs) with low operating voltages and high switching speed. PIL block copolymer structure and self-assembly can influence ion conductivity and the resulting OTFT performance. In an OTFT, self-assembly of the PIL gate on the semiconducting polymer may differ from bulk self-assembly, which would directly influence electrical double-layer formation. To this end, we used poly{[N,N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)} (P(NDI2OD-T2)) as a model semiconductor for our OTFTs, on which our PILs exhibited self-assembly. In this study, we explore this critical interface by grazing-incidence small-angle X-ray scattering (GISAXS) and atomic force microscopy (AFM) of P(NDI2OD-T2) and a series of poly(styrene)-b-poly(1-(4-vinylbenzyl)-3-butylimidazolium-random-poly(ethylene glycol) methyl ether methacrylate) (poly(S)-b-poly(VBBI+[X]-r-PEGMA)) block copolymers with varying PEGMA/VBBI+ ratios and three different mobile anions (where X = TFSI-, PF6-, or BF4-). We investigate the thin-film self-assembly of block copolymers as a function of device performance. Overall, a mixed orientation at the interface leads to improved device performance, while predominantly hexagonal packing leads to nonfunctional devices, regardless of the anion present. These PIL gated OTFTs were characterized with a threshold voltage below 1 V, making understanding of their structure-property relationships crucial to enabling the further development of high-performance gating materials.

17.
Cell Rep ; 40(9): 111293, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36044854

RESUMO

N6-methyladenosine (m6A) is deposited co-transcriptionally on thousands of cellular mRNAs and plays important roles in mRNA processing and cellular function. m6A is particularly abundant within the brain and is critical for neurodevelopment. However, the mechanisms through which m6A contributes to brain development are incompletely understood. RBM45 acts as an m6A-binding protein that is highly expressed during neurodevelopment. We find that RBM45 binds to thousands of cellular RNAs, predominantly within intronic regions. Rbm45 depletion disrupts the constitutive splicing of a subset of target pre-mRNAs, leading to altered mRNA and protein levels through both m6A-dependent and m6A-independent mechanisms. Finally, we find that RBM45 is necessary for neuroblastoma cell differentiation and that its depletion impacts the expression of genes involved in several neurodevelopmental signaling pathways. Altogether, our findings show a role for RBM45 in controlling mRNA processing and neuronal differentiation, mediated in part by the recognition of methylated RNA.


Assuntos
Proteínas de Transporte , Proteínas de Ligação a RNA , Proteínas de Transporte/metabolismo , Ligação Proteica , RNA/metabolismo , Splicing de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
18.
Nucleic Acids Res ; 50(8): 4464-4483, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35438793

RESUMO

The transport of mRNAs to distal subcellular compartments is an important component of spatial gene expression control in neurons. However, the mechanisms that control mRNA localization in neurons are not completely understood. Here, we identify the abundant base modification, m6A, as a novel regulator of this process. Transcriptome-wide analysis following genetic loss of m6A reveals hundreds of transcripts that exhibit altered subcellular localization in hippocampal neurons. Additionally, using a reporter system, we show that mutation of specific m6A sites in select neuronal transcripts diminishes their localization to neurites. Single molecule fluorescent in situ hybridization experiments further confirm our findings and identify the m6A reader proteins YTHDF2 and YTHDF3 as mediators of this effect. Our findings reveal a novel function for m6A in controlling mRNA localization in neurons and enable a better understanding of the mechanisms through which m6A influences gene expression in the brain.


Assuntos
Metiltransferases/metabolismo , Proteínas de Ligação a RNA , Adenina/metabolismo , Encéfalo/metabolismo , Hibridização in Situ Fluorescente , Neurônios/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
19.
Mol Cell ; 82(4): 868-878.e10, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35081365

RESUMO

N6-methyladenosine (m6A) is an abundant RNA modification that plays critical roles in RNA regulation and cellular function. Global m6A profiling has revealed important aspects of m6A distribution and function, but to date such studies have been restricted to large populations of cells. Here, we develop a method to identify m6A sites transcriptome-wide in single cells. We uncover surprising heterogeneity in the presence and abundance of m6A sites across individual cells and identify differentially methylated mRNAs across the cell cycle. Additionally, we show that cellular subpopulations can be distinguished based on their RNA methylation signatures, independent from gene expression. These studies reveal fundamental features of m6A that have been missed by m6A profiling of bulk cells and suggest the presence of cell-intrinsic mechanisms for m6A deposition.


Assuntos
Adenosina/análogos & derivados , Perfilação da Expressão Gênica , Processamento Pós-Transcricional do RNA , RNA Mensageiro/metabolismo , Análise de Sequência de RNA , Análise de Célula Única , Transcriptoma , Adenosina/metabolismo , Células HEK293 , Humanos , Metilação , RNA Mensageiro/genética
20.
Cardiovasc Diagn Ther ; 12(6): 787-802, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36605074

RESUMO

Background: Aortic aneurysm and aortic dissection can have a major impact on the life expectancy of Marfan syndrome (MFS) or Loeys-Dietz syndrome (LDS) patients. Although obesity can influence the development of aortic complications, evidence on whether obesity influences the development of aortic aneurysm or dissection in MFS and LDS is limited. The aim of the present study was to elucidate the relationship between aortic size and body composition, assessed by modern bioelectrical impedance analysis (BIA) in MFS/LDS-patients. Methods: In this exploratory cross-sectional study in MFS or LDS patients, enrolled between June 2020 and May 2022, 34 patients received modern BIA and magnetic resonance imaging (MRI) (n=32) or computed tomography (CT) imaging (n=2) of the entire aorta. A P value of <0.05 was considered significant. Results: Fifty-one patients (66% female; mean age: 37.7±11.7; range, 17-68 years) with MFS or LDS were enrolled; 34 patients, 27 with MFS and 7 with LDS, underwent aortic MRI or CT scanning. The mean aortic length was 503.7±58.7 mm, and the mean thoracic aortic length and abdominal aortic length were 351.5±52.4 and 152.2±27.4 mm, respectively. The aortic bulb and the ascending aorta were measured only in the non-surgically repaired patients. Fifteen MFS (88.2%) and two LDS (40.0%) patients had an aortic aneurysm. In these, the aortic bulb tended to be larger in MFS than in LDS patients [42.6×41.9×41.2 vs. 37.8×37.4×36.8 mm; P=0.07 (-1.1; 9.1); P=0.07 (-1.2; 8.4); P=0.07 (-1.5; 7.9)]. BIA revealed mean body fat levels of 31.6%±8.7% (range, 9.5-53.5%), indicating that 18 patients (52.9%) were obese. There was a significant correlation between body fat content and thoracic aortic length (R=-0.377; P=0.02), muscle mass and total aortic length (R=0.359; P=0.03), thoracic aortic length (R=0.399; P=0.02), extracellular mass (ECM), and total aortic length (R=0.354; P=0.04), and connective tissue and aortic diameters at the aortic arch (R=0.511; P=0.002), aortic isthmus (R=0.565; P<0.001), and abdominal aorta (R=0.486; P=0.004). Older age was correlated with wider aortic arch, isthmus, and abdominal aorta. Male patients had a longer aorta. Conclusions: While a slender habitus is commonly known for MFS and LDS patients, our data show that many MFS and LDS patients (especially female) do not fit this phenotypic characteristic and are obese, which is associated with a more severe aortic phenotype. This topic should be included in the clinical assessment of affected MFS and LDS patients, in addition to measurement of the aortic diameters. Physicians should systematically screen MFS and LDS patients for obesity, educate them about the potential risk of resulting aortic complications, and encourage them to adopt a healthy lifestyle, that includes (mild) exercise and a balanced diet.

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