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1.
Mol Cell ; 67(6): 1059-1067.e4, 2017 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-28867294

RESUMEN

YTHDF2 binds and destabilizes N6-methyladenosine (m6A)-modified mRNA. The extent to which this branch of m6A RNA-regulatory pathway functions in vivo and contributes to mammalian development remains unknown. Here we find that YTHDF2 deficiency is partially permissive in mice and results in female-specific infertility. Using conditional mutagenesis, we demonstrate that YTHDF2 is autonomously required within the germline to produce MII oocytes that are competent to sustain early zygotic development. Oocyte maturation is associated with a wave of maternal RNA degradation, and the resulting relative changes to the MII transcriptome are integral to oocyte quality. The loss of YTHDF2 results in the failure to regulate transcript dosage of a cohort of genes during oocyte maturation, with enrichment observed for the YTHDF2-binding consensus and evidence of m6A in these upregulated genes. In summary, the m6A-reader YTHDF2 is an intrinsic determinant of mammalian oocyte competence and early zygotic development.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Meiosis , Oocitos/metabolismo , Procesamiento Postranscripcional del ARN , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo , Transcripción Genética , Transcriptoma , Cigoto/metabolismo , Animales , Sitios de Unión , Femenino , Fertilidad , Genotipo , Infertilidad Femenina/genética , Infertilidad Femenina/metabolismo , Infertilidad Femenina/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Oocitos/patología , Fenotipo , Unión Proteica , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Cigoto/patología
2.
Clin Gastroenterol Hepatol ; 22(10): 2062-2074.e11, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38782175

RESUMEN

BACKGROUND & AIMS: Obeticholic acid (OCA) is the only licensed second-line therapy for primary biliary cholangitis (PBC). With novel therapeutics in advanced development, clinical tools are needed to tailor the treatment algorithm. We aimed to derive and externally validate the OCA response score (ORS) for predicting the response probability of individuals with PBC to OCA. METHODS: We used data from the Italian RECAPITULATE (N = 441) and the IBER-PBC (N = 244) OCA real-world prospective cohorts to derive/validate a score including widely available variables obtained either pre-treatment (ORS) or also after 6 months of treatment (ORS+). Multivariable Cox regressions with backward selection were applied to obtain parsimonious predictive models. The predicted outcomes were biochemical response according to POISE (alkaline phosphatase [ALP]/upper limit of normal [ULN]<1.67 with a reduction of at least 15%, and normal bilirubin), or ALP/ULN<1.67, or normal range criteria (NR: normal ALP, alanine aminotransferase [ALT], and bilirubin) up to 24 months. RESULTS: Depending on the response criteria, ORS included age, pruritus, cirrhosis, ALP/ULN, ALT/ULN, GGT/ULN, and bilirubin. ORS+ also included ALP/ULN and bilirubin after 6 months of OCA therapy. Internally validated c-statistics for ORS were 0.75, 0.78, and 0.72 for POISE, ALP/ULN<1.67, and NR response, which raised to 0.83, 0.88, and 0.81 with ORS+, respectively. The respective performances in validation were 0.70, 0.72, and 0.71 for ORS and 0.80, 0.84, and 0.78 for ORS+. Results were consistent across groups with mild/severe disease. CONCLUSIONS: We developed and externally validated a scoring system capable to predict OCA response according to different criteria. This tool will enhance a stratified second-line therapy model to streamline standard care and trial delivery in PBC.


Asunto(s)
Ácido Quenodesoxicólico , Humanos , Ácido Quenodesoxicólico/análogos & derivados , Ácido Quenodesoxicólico/uso terapéutico , Femenino , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Anciano , Cirrosis Hepática Biliar/tratamiento farmacológico , Resultado del Tratamiento , Adulto , Colagogos y Coleréticos/uso terapéutico , Italia
3.
Mol Psychiatry ; 28(10): 4307-4319, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37131072

RESUMEN

Current knowledge about functional connectivity in obsessive-compulsive disorder (OCD) is based on small-scale studies, limiting the generalizability of results. Moreover, the majority of studies have focused only on predefined regions or functional networks rather than connectivity throughout the entire brain. Here, we investigated differences in resting-state functional connectivity between OCD patients and healthy controls (HC) using mega-analysis of data from 1024 OCD patients and 1028 HC from 28 independent samples of the ENIGMA-OCD consortium. We assessed group differences in whole-brain functional connectivity at both the regional and network level, and investigated whether functional connectivity could serve as biomarker to identify patient status at the individual level using machine learning analysis. The mega-analyses revealed widespread abnormalities in functional connectivity in OCD, with global hypo-connectivity (Cohen's d: -0.27 to -0.13) and few hyper-connections, mainly with the thalamus (Cohen's d: 0.19 to 0.22). Most hypo-connections were located within the sensorimotor network and no fronto-striatal abnormalities were found. Overall, classification performances were poor, with area-under-the-receiver-operating-characteristic curve (AUC) scores ranging between 0.567 and 0.673, with better classification for medicated (AUC = 0.702) than unmedicated (AUC = 0.608) patients versus healthy controls. These findings provide partial support for existing pathophysiological models of OCD and highlight the important role of the sensorimotor network in OCD. However, resting-state connectivity does not so far provide an accurate biomarker for identifying patients at the individual level.


Asunto(s)
Conectoma , Trastorno Obsesivo Compulsivo , Humanos , Conectoma/métodos , Mapeo Encefálico/métodos , Imagen por Resonancia Magnética/métodos , Encéfalo , Biomarcadores , Vías Nerviosas
4.
Appetite ; 201: 107581, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38945368

RESUMEN

The Mediterranean Diet has been recognized as one of the healthiest and most sustainable dietary patterns and is flavor rich due to the use of different seasonings, such as aromatic plants, in dish confection. Based on the hypotheses that: 1) gustatory function will affect food choices; 2) seasoning flavors may be differently accepted according to individuals' gustatory functions; the aim of the present study was to assess the association between taste sensitivity and/or preference with Mediterranean Diet adherence and seasoning consumption. A total of 383 adults (18-59 years old; 198 female, 185 male) from North Alentejo region of Portugal were enrolled in this study, with 291 (145 female and 146 male) also evaluated for gustatory function. Recognition thresholds were obtained for four tastes (sweet, sour, salty, and bitter) and astringency, as well as preference level for the highest concentration of each stimulus tested. A validated Food Frequency Questionnaire was filled out, and MD adherence was extrapolated from the answers of the Food Frequency Questionnaire according to the Mediterranean Diet Adherence Screener (MEDAS) score. In total, 20.8% of the individuals presented low, 58.2% medium, and 21.0% high adherence. Adherence was higher in women than men and in older individuals than younger adults. Adherence to the Mediterranean Diet was positively correlated with aromatic plants consumption but not spices. Seasonings were associated with gustatory function, and the cluster with higher consumption presented higher preferences for bitter and salty tastes. Total sodium intake was also higher in this cluster, suggesting that these individuals prefer stronger oral sensations. In conclusion, this study shows that MD adherence is not high, even in regions with rural characteristics. The observed association of MD and seasoning intake with gustatory function do underline the usefulness of this information in strategies aimed at promoting healthy and sustainable eating patterns.


Asunto(s)
Dieta Mediterránea , Preferencias Alimentarias , Gusto , Humanos , Femenino , Masculino , Adulto , Portugal , Dieta Mediterránea/estadística & datos numéricos , Persona de Mediana Edad , Adulto Joven , Adolescente , Cooperación del Paciente/estadística & datos numéricos , Encuestas y Cuestionarios , Conducta Alimentaria/psicología , Umbral Gustativo/fisiología
5.
Appetite ; 198: 107377, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38679064

RESUMEN

Most instruments measuring nutrition literacy evaluate theoretical knowledge, not necessarily reflecting skills relevant to food choices. We aimed to develop and validate a photograph-based instrument to assess nutrition literacy (NUTLY) among adults in Portugal. NUTLY assesses the ability to distinguish foods with different nutritional profiles; from each of several combinations of three photographs (two foods with similar contents and one with higher content) participants are asked to identify the food with the highest energy/sodium content. The NUTLY version with 79 combinations, obtained after experts/lay people evaluations, was applied to a sample representing different age, gender and education groups (n = 329). Dimensionality was evaluated through latent trait models. Combinations with negative or with positive small factor loadings were excluded after critical assessment. Internal consistency was measured using Cronbach's alpha and construct validity by comparing NUTLY scores with those obtained in the Medical Term Recognition Test and the Newest Vital Sign (NVS), and across education and training in nutrition/health groups. The cut-off to distinguish adequate/inadequate nutrition literacy was defined through ROC analysis using the Youden index criterion, after performing a Latent class analysis which identified a two-class model to have the best goodness of fit. Test-retest reliability was assessed after one month (n = 158). The final NUTLY scale was unidimensional and included 48 combinations (energy: 33; sodium: 15; α = 0.74). Mean scores (±standard deviation) were highest among nutritionists (39.9 ± 4.4), followed by health professionals (38.5 ± 4.1) and declined with decreasing education (p < 0.001). Those with adequate nutrition literacy according to NVS showed higher NUTLY scores (37.9 ± 4.3 vs. 33.9 ± 6.9, p < 0.001). Adequate nutrition literacy was defined as a NUTLY score≥35 (sensitivity: 89.3%; specificity: 93.7%). Test-retest reliability was high (ICC = 0.77). NUTLY is a valid and reliable nutrition literacy measurement tool.


Asunto(s)
Alfabetización en Salud , Fotograbar , Humanos , Femenino , Masculino , Adulto , Reproducibilidad de los Resultados , Portugal , Persona de Mediana Edad , Adulto Joven , Conocimientos, Actitudes y Práctica en Salud , Anciano , Encuestas y Cuestionarios/normas , Adolescente
6.
IEEE Sens J ; 24(11): 18359-18371, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39301509

RESUMEN

Needle insertion using flexible bevel tip needles are a common minimally-invasive surgical technique for prostate cancer interventions. Flexible, asymmetric bevel tip needles enable physicians for complex needle steering techniques to avoid sensitive anatomical structures during needle insertion. For accurate placement of the needle, predicting the trajectory of these needles intra-operatively would greatly reduce the need for frequently needle reinsertions thus improving patient comfort and positive outcomes. However, predicting the trajectory of the needle during insertion is a complex task that has yet to be solved due to random needle-tissue interactions. In this paper, we present and validate for the first time a hybrid deep learning and model-based approach to handle the intra-operative needle shape prediction problem through, leveraging a validated Lie-group theoretic model for needle shape representation. Furthermore, we present a novel self-supervised learning and method in conjunction with the Lie-group shape model for training these networks in the absence of data, enabling further refinement of these networks with transfer learning. Needle shape prediction was performed in single-layer and double-layer homogeneous phantom tissue for C- and S-shape needle insertions. Our method demonstrates an average root-mean-square prediction error of 1.03 mm over a dataset containing approximately 3,000 prediction samples with maximum prediction steps of 110 mm.

7.
Mol Psychiatry ; 27(12): 4939-4947, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36117211

RESUMEN

The significant link between stress and psychiatric disorders has prompted research on stress's impact on the brain. Interestingly, previous studies on healthy subjects have demonstrated an association between perceived stress and amygdala volume, although the mechanisms by which perceived stress can affect brain function remain unknown. To better understand what this association entails at a functional level, herein, we explore the association of perceived stress, measured by the PSS10 questionnaire, with disseminated functional connectivity between brain areas. Using resting-state fMRI from 252 healthy subjects spanning a broad age range, we performed both a seed-based amygdala connectivity analysis (static connectivity, with spatial resolution but no temporal definition) and a whole-brain data-driven approach to detect altered patterns of phase interactions between brain areas (dynamic connectivity with spatiotemporal information). Results show that increased perceived stress is directly associated with increased amygdala connectivity with frontal cortical regions, which is driven by a reduced occurrence of an activity pattern where the signals in the amygdala and the hippocampus evolve in opposite directions with respect to the rest of the brain. Overall, these results not only reinforce the pathological effect of in-phase synchronicity between subcortical and cortical brain areas but also demonstrate the protective effect of counterbalanced (i.e., phase-shifted) activity between brain subsystems, which are otherwise missed with correlation-based functional connectivity analysis.


Asunto(s)
Amígdala del Cerebelo , Encéfalo , Humanos , Encéfalo/patología , Lóbulo Frontal , Mapeo Encefálico , Imagen por Resonancia Magnética/métodos , Vías Nerviosas , Estrés Psicológico
8.
Eur Radiol ; 33(1): 461-471, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35771247

RESUMEN

OBJECTIVES: The Prostate Imaging Quality (PI-QUAL) score is a new metric to evaluate the diagnostic quality of multiparametric magnetic resonance imaging (MRI) of the prostate. This study assesses the impact of an intervention, namely a prostate MRI quality training lecture, on the participant's ability to apply PI-QUAL. METHODS: Sixteen participants (radiologists, urologists, physicists, and computer scientists) of varying experience in reviewing diagnostic prostate MRI all assessed the image quality of ten examinations from different vendors and machines. Then, they attended a dedicated lecture followed by a hands-on workshop on MRI quality assessment using the PI-QUAL score. Five scans assessed by the participants were evaluated in the workshop using the PI-QUAL score for teaching purposes. After the course, the same participants evaluated the image quality of a new set of ten scans applying the PI-QUAL score. Results were assessed using receiver operating characteristic analysis. The reference standard was the PI-QUAL score assessed by one of the developers of PI-QUAL. RESULTS: There was a significant improvement in average area under the curve for the evaluation of image quality from baseline (0.59 [95 % confidence intervals: 0.50-0.66]) to post-teaching (0.96 [0.92-0.98]), an improvement of 0.37 [0.21-0.41] (p < 0.001). CONCLUSIONS: A teaching course (dedicated lecture + hands-on workshop) on PI-QUAL significantly improved the application of this scoring system to assess the quality of prostate MRI examinations. KEY POINTS: • A significant improvement in the application of PI-QUAL for the assessment of prostate MR image quality was observed after an educational intervention. • Appropriate training on image quality can be delivered to those involved in the acquisition and interpretation of prostate MRI. • Further investigation will be needed to understand the impact on improving the acquisition of high-quality diagnostic prostate MR examinations.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de la Próstata , Masculino , Humanos , Próstata/diagnóstico por imagen , Próstata/patología , Becas , Neoplasias de la Próstata/patología , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos
9.
Br J Nutr ; 129(11): 1984-1992, 2023 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-35979684

RESUMEN

In the context of the global childhood obesity, it is essential to monitor the nutrition value of commercial foods. A cross-sectional study (November 2018 to April 2019) aimed to evaluate the nutritional adequacy of processed/ultra-processed food products targeted at 0-36-month-old children in Portugal and in Brazil. The nutrient profiling model developed by the Pan American Health Organization was used. A total of food 171 products were assessed (123 in Portugal and forty eight in Brazil). From the fifteen available meat- or fish-based meals in Brazil, 60 % exceeded the amount of Na and 100 % exceeded the target for total fat. Given the lack of specification of sugars within carbohydrates in the label of the foods in Brazil, it was not possible to calculate free sugars. In Portugal, from the seventeen fruit and vegetable purees and the six juice/smoothie/tea/drinks available, 82 % and 67 %, respectively, surpassed the level of free sugar, while total and saturated fat was excessive in all yogurt and yogurt-related products (n 21), 40 % of biscuit/wafer/crisps (two out of five) and 13 % meat- or fish-based meals (two out of sixteen). These findings demonstrate the relevance of improving the nutritional profile of some food products targeted to young children.


Asunto(s)
Obesidad Infantil , Humanos , Portugal , Brasil , Estudios Transversales , Valor Nutritivo , Comidas , Azúcares
10.
Dig Dis ; 41(1): 154-163, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35970144

RESUMEN

BACKGROUND AND AIMS: EUS-guided through-the-needle microforceps biopsy (EUS-TTNB) was introduced as a new diagnostic tool to establish pancreatic cyst histotype and help to better risk stratify the patients. The aim of this study was to describe the technical success, diagnostic yield, and adverse events of through-the-needle biopsy and discuss the technique variations, focusing on future procedure standardization. METHODS: We performed a prospective single-center study including patients with presumed mucinous cysts harboring worrisome features or indeterminate cyst type on imaging, submitted to EUS-TTNB using Moray® microforceps between March 2018 and September 2021. Specimens were processed as a cell-block. RESULTS: We included 40 patients. Technical success was 97.5%. The diagnostic yield was 72.5% for TTNB whereas for cyst fluid cytology/analysis it was 27.5%. Moreover, without TTNB 5 mucinous lesions would not have been diagnosed. TTNB had a sensitivity of 76% and a specificity of 91%, while FNA cytology had a sensitivity and specificity of 35% and 91%, respectively. Moreover for IPMN lesions, subtyping was possible in 63% of cases. TTNB resulted in change in clinical management in 20% of patients. We registered three adverse events: 2 self-limited intracystic bleeding and 1 patient with abdominal pain not associated with pancreatitis. CONCLUSION: TTNB proved superior to cyst fluid analysis and cytology for the definition of cyst histotype and mucinous cyst diagnosis with acceptable risk profile. Further studies should explore the best steps for procedure standardization.


Asunto(s)
Quiste Pancreático , Neoplasias Pancreáticas , Humanos , Estudios Prospectivos , Neoplasias Pancreáticas/diagnóstico , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Quiste Pancreático/diagnóstico , Quiste Pancreático/patología , Endosonografía
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