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1.
Nutrients ; 16(6)2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38542810

RESUMEN

This multi-center prospective randomized controlled trial was a tolerance and safety study investigating the thickener locust bean gum (LBG) in infants with regurgitation, to support the re-evaluation of the safety of LBG in infant formula. The primary objective was to demonstrate that after an 8-week intervention, stool consistency was not inferior (i.e., was not looser or more watery) in infants fed an anti-regurgitation (AR) formula containing LBG vs. the stool consistency of infants fed with an unthickened control formula. A total of 103 full-term infants with regurgitation were randomized to the test or control formula. The test formula contained LBG (0.4 g/100 mL), short-chain galacto-oligosaccharides, and long-chain fructo-oligosaccharides (scGOS/lcFOS; 9:1; 0.4 g/100 mL) and postbiotics and the control formula contained scGOS/lcFOS (0.8 g/100 mL), the same amount of postbiotics, and did not contain LBG. The average stool consistency score at the 8th intervention week was the primary outcome parameter. Secondary outcome parameters were stool consistency at other timepoints, stool frequency, Infant Gastrointestinal Symptom Questionnaire (IGSQ) score, growth, (serious) adverse events ([S]AEs), regurgitation severity, and infant well-being. Overall, the infants were 36.9 ± 12.9 [mean ± SD] days old, 62.7% girls in the test, and 50.0% girls in the control group. The primary analysis showed that the test group did not have looser or more watery stools than the control group. IGSQ sum scores decreased comparably in both groups. The frequency of regurgitation was significantly lower in the test group compared to the control group (mixed model repeated measurement, p ≤ 0.028) and parent-reported well-being scores were favorable. Adequate growth was observed in both groups. Both products were well-tolerated and safe and the AR formula with LBG was efficacious in reducing regurgitation frequency. This study provides further evidence for the dietary management of regurgitation by LBG-containing formulae in infants who are not exclusively breastfed, and the reassurance it can bring to parents.


Asunto(s)
Galactanos , Enfermedades Gastrointestinales , Gomas de Plantas , Lactante , Femenino , Humanos , Masculino , Estudios Prospectivos , Galactanos/efectos adversos , Mananos , Vómitos , Heces , Oligosacáridos/efectos adversos , Enfermedades Gastrointestinales/inducido químicamente , Fórmulas Infantiles/efectos adversos , Método Doble Ciego
2.
Acta Paediatr ; 112(6): 1333-1340, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36843346

RESUMEN

AIM: The aim of the study was to develop a deep convolutional neural networks (CNNs) algorithm for automated assessment of stool consistency from diaper photographs and test its performance under real-world conditions. METHODS: Diaper photographs were enrolled via a mobile phone application. The stool consistency was assessed independently according to the Brussels Infant and Toddler Stool Scale (BITSS) by paediatricians. These images were randomised into a training data set and a test data set. After training and testing, the new algorithm was used under real-world conditions by parents. RESULTS: There was an overall agreement of 92.9% between paediatricians and the CNN-generated algorithm. Post hoc classification into the validated 4 categories of the BITSS yielded an agreement of 95.4%. Spearman correlation analysis across the ranking of 7 BITSS photographs and validated 4 categories showed a significant correlation of rho = 0.93 (95% CI, 0.92, 0.94; p < 0.001) and rho = 0.92 (95% CI, 0.90, 0.93; p < 0.001), respectively. The real-world application yielded further insights into changes in stool consistency between age categories and mode of feeding. CONCLUSION: The new CNN-based algorithm is able to reliably identify stool consistency from diaper photographs and may support the communication between parents and paediatricians.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Humanos , Lactante , Heces , Padres , Pediatras
3.
Int J Gastron Food Sci ; 31: 100687, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36844903

RESUMEN

Over the last three years, COVID-19, with its lockdowns, social restrictions, and work from home structures, had a significant influence on our daily lives. The resulting changes in technology practices are likely to be explored in the years ahead. We will contribute to this exploration by looking specifically at the impact of COVID-19 on everyday food practices and the role of involved technology. To explore food practices and technology use, we conducted a qualitative interview study with 16 interviewees and delved into the underlying influencing factors behind them. Thereby we can better understand potential behavioral changes and technology usage by people to design not only for future pandemics and exceptional situations but to also for non-pandemic times.

4.
Science ; 379(6629): 253-260, 2023 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-36656928

RESUMEN

Cancer genetics has to date focused on epithelial malignancies, identifying multiple histotype-specific pathways underlying cancer susceptibility. Sarcomas are rare malignancies predominantly derived from embryonic mesoderm. To identify pathways specific to mesenchymal cancers, we performed whole-genome germline sequencing on 1644 sporadic cases and 3205 matched healthy elderly controls. Using an extreme phenotype design, a combined rare-variant burden and ontologic analysis identified two sarcoma-specific pathways involved in mitotic and telomere functions. Variants in centrosome genes are linked to malignant peripheral nerve sheath and gastrointestinal stromal tumors, whereas heritable defects in the shelterin complex link susceptibility to sarcoma, melanoma, and thyroid cancers. These studies indicate a specific role for heritable defects in mitotic and telomere biology in risk of sarcomas.


Asunto(s)
Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Mitosis , Sarcoma , Telómero , Humanos , Variación Genética , Células Germinativas , Melanoma/genética , Mitosis/genética , Sarcoma/genética , Complejo Shelterina/genética , Telómero/genética
5.
PLoS Genet ; 18(9): e1009923, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36112662

RESUMEN

Rare variant association tests (RVAT) have been developed to study the contribution of rare variants widely accessible through high-throughput sequencing technologies. RVAT require to aggregate rare variants in testing units and to filter variants to retain only the most likely causal ones. In the exome, genes are natural testing units and variants are usually filtered based on their functional consequences. However, when dealing with whole-genome sequence (WGS) data, both steps are challenging. No natural biological unit is available for aggregating rare variants. Sliding windows procedures have been proposed to circumvent this difficulty, however they are blind to biological information and result in a large number of tests. We propose a new strategy to perform RVAT on WGS data: "RAVA-FIRST" (RAre Variant Association using Functionally-InfoRmed STeps) comprising three steps. (1) New testing units are defined genome-wide based on functionally-adjusted Combined Annotation Dependent Depletion (CADD) scores of variants observed in the gnomAD populations, which are referred to as "CADD regions". (2) A region-dependent filtering of rare variants is applied in each CADD region. (3) A functionally-informed burden test is performed with sub-scores computed for each genomic category within each CADD region. Both on simulations and real data, RAVA-FIRST was found to outperform other WGS-based RVAT. Applied to a WGS dataset of venous thromboembolism patients, we identified an intergenic region on chromosome 18 enriched for rare variants in early-onset patients. This region that was missed by standard sliding windows procedures is included in a TAD region that contains a strong candidate gene. RAVA-FIRST enables new investigations of rare non-coding variants in complex diseases, facilitated by its implementation in the R package Ravages.


Asunto(s)
Variación Genética , Genómica , ADN Intergénico , Exoma , Variación Genética/genética , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos
6.
J Pediatr Gastroenterol Nutr ; 75(5): 584-588, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35948372

RESUMEN

OBJECTIVES: The Brussels Infants and Toddlers Stool Scale (BITSS) was developed for the assessment of stool consistency in non-toilet-trained children. This study aimed to (1) investigate the intra-rater reliability of the BITSS among health care professionals (HCPs) and caregivers (CGs); (2) study a potential learning curve; (3) explore the impact of photo quality on intra-rater reliability. METHODS: Photos of diapers containing stool were assessed twice by 4 HCP (2432 photos) and 8 CGs (492 photos) using the BITTS. Intra-rater reliability was calculated by the percentage of exact agreement and a κ-value. A learning effect and the impact of photo quality was explored using mixed linear model and generalized estimating equations. RESULTS: HCPs generated 24,320 stool consistency ratings: 12.1% were scored as watery, 31.0% loose, 29.4% formed, and 27.6% hard. CGs performed 7872 ratings: 9.2% classified as watery, 34.6% loose, 28.9% formed, and 27.3% hard. Intra-rater reliability (κ) for HCPs ranged from 0.64 [95% confidence interval (CI) = 0.61-0.66] to 0.78 (95% CI = 0.76-0.80) and from 0.68 (95% CI = 0.63-0.73) to 0.94 (95% CI = 0.91-0.97) in the CG group. Both groups had <1% improvement in the odds of identical classification per 50 photos. The percentage of absolute agreement was higher in photos rated as good quality than those that were not (HCPs: 80.3% vs 69.5%, P < 0.001; CGs: 90.4% vs 86.3%, P < 0.001). CONCLUSIONS: The BITSS has an excellent intra-rater reliability for the stool consistency scoring of photographs of stools in diapers, but can be influenced by photo quality. A clinically meaningless learning effect was found.


Asunto(s)
Cuidadores , Lactante , Humanos , Preescolar , Reproducibilidad de los Resultados , Heces , Variaciones Dependientes del Observador
7.
J Inherit Metab Dis ; 45(5): 996-1012, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35621276

RESUMEN

Mitochondrial complex V plays an important role in oxidative phosphorylation by catalyzing the generation of ATP. Most complex V subunits are nuclear encoded and not yet associated with recognized Mendelian disorders. Using exome sequencing, we identified a rare homozygous splice variant (c.87+3A>G) in ATP5PO, the complex V subunit which encodes the oligomycin sensitivity conferring protein, in three individuals from two unrelated families, with clinical suspicion of a mitochondrial disorder. These individuals had a similar, severe infantile and often lethal multi-systemic disorder that included hypotonia, developmental delay, hypertrophic cardiomyopathy, progressive epileptic encephalopathy, progressive cerebral atrophy, and white matter abnormalities on brain MRI consistent with Leigh syndrome. cDNA studies showed a predominant shortened transcript with skipping of exon 2 and low levels of the normal full-length transcript. Fibroblasts from the affected individuals demonstrated decreased ATP5PO protein, defective assembly of complex V with markedly reduced amounts of peripheral stalk proteins, and complex V hydrolytic activity. Further, expression of human ATP5PO cDNA without exon 2 (hATP5PO-∆ex2) in yeast cells deleted for yATP5 (ATP5PO homolog) was unable to rescue growth on media which requires oxidative phosphorylation when compared to the wild type construct (hATP5PO-WT), indicating that exon 2 deletion leads to a non-functional protein. Collectively, our findings support the pathogenicity of the ATP5PO c.87+3A>G variant, which significantly reduces but does not eliminate complex V activity. These data along with the recent report of an affected individual with ATP5PO variants, add to the evidence that rare biallelic variants in ATP5PO result in defective complex V assembly, function and are associated with Leigh syndrome.


Asunto(s)
Encefalopatías , Enfermedad de Leigh , ATPasas de Translocación de Protón Mitocondriales , Encefalopatías/metabolismo , ADN Complementario/metabolismo , Humanos , Enfermedad de Leigh/genética , Enfermedad de Leigh/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , ATPasas de Translocación de Protón Mitocondriales/genética , Mutación , Proteínas/metabolismo
8.
Genet Epidemiol ; 46(5-6): 256-265, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35419876

RESUMEN

Next-generation sequencing technologies have opened up the possibility to sequence large samples of cases and controls to test for association with rare variants. To limit cost and increase sample sizes, data from controls could be used in multiple studies and might thus be generated on different sequencing platforms. This could pose some problems of comparability between cases and controls due to batch effects that could be confounding factors, leading to false-positive association signals. To limit batch effects and ensure comparability of datasets, stringent quality controls are required. We propose an integrative five-steps pipeline, RAVAQ, that (a) performs a specific three-step quality control taking into account the case-control status to ensure data comparability, (b) selects qualifying variants as defined by the user, and (c) performs rare variant association tests per genomic region. The RAVAQ pipeline is wrapped in an R package. It is user-friendly and flexible in its arguments to adapt to the specificity of each research project. We provide examples showing how RAVAQ improves rare variant association tests. The default RAVAQ quality control outperformed the widely used Variant Quality Score Recalibration method, removing inflation due to spurious signals. RAVAQ is open source and freely available at https://gitlab.com/gmarenne/ravaq.


Asunto(s)
Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Estudios de Casos y Controles , Genoma , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Control de Calidad , Programas Informáticos
9.
J Am Chem Soc ; 143(46): 19341-19355, 2021 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-34752077

RESUMEN

Accurate theoretical simulation of electrochemical activation barriers is key to understanding electrocatalysis and guides the design of more efficient catalysts. Providing a detailed picture of proton transfer processes encounters several challenges: the constant potential requirement during charge transfer, the different time scales involved in the processes, and the thermal fluctuation of the solvent. Hence, it is prohibitively expensive computationally to apply density functional theory (DFT) calculations in modeling the potential-dependent activation barrier at the electrode-solvent interface, and the results are dubious. To address these challenges, we have developed an analytical approach based on charge conservation and decoupled potential energy surfaces to compute charge transfer barriers. The method makes it possible to simulate an electrochemical process at different potentials and explicitly include thermal fluctuations of the solvent at the electrode-solvent interface. We use the Pt-catalyzed alkaline hydrogen evolution reaction (HER) as our benchmark reaction, and we model the microkinetics of HER with consideration of the spatial fluctuations between the metal surface and the first solvent layer at room temperature. The distribution of water-metal distances has a large effect on the barriers of the charge transfer processes, and an accurate account of the statistical fluctuation in the reaction network leads to a several orders of magnitude increase in HER current as compared to transfer from a static solvent. The trends of the different reaction mechanisms in HER were successfully simulated with our model, and the theoretical I-V curves obtained are in good qualitative agreement with experimental results.

10.
Ann Neurol ; 90(6): 962-975, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34606115

RESUMEN

OBJECTIVE: The majority of patients with a familial cerebral small vessel disease (CSVD) referred for molecular screening do not show pathogenic variants in known genes. In this study, we aimed to identify novel CSVD causal genes. METHODS: We performed a gene-based collapsing test of rare protein-truncating variants identified in exome data of 258 unrelated CSVD patients of an ethnically matched control cohort and of 2 publicly available large-scale databases, gnomAD and TOPMed. Western blotting was used to investigate the functional consequences of variants. Clinical and magnetic resonance imaging features of mutated patients were characterized. RESULTS: We showed that LAMB1 truncating variants escaping nonsense-mediated messenger RNA decay are strongly overrepresented in CSVD patients, reaching genome-wide significance (p < 5 × 10-8 ). Using 2 antibodies recognizing the N- and C-terminal parts of LAMB1, we showed that truncated forms of LAMB1 are expressed in the endogenous fibroblasts of patients and trapped in the cytosol. These variants are associated with a novel phenotype characterized by the association of a hippocampal type episodic memory defect and a diffuse vascular leukoencephalopathy. INTERPRETATION: These findings are important for diagnosis and clinical care, to avoid unnecessary and sometimes invasive investigations, and also from a mechanistic point of view to understand the role of extracellular matrix proteins in neuronal homeostasis. ANN NEUROL 2021;90:962-975.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales/genética , Hipocampo/diagnóstico por imagen , Laminina/genética , Leucoencefalopatías/genética , Trastornos de la Memoria/genética , Adulto , Anciano , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Exoma , Femenino , Humanos , Leucoencefalopatías/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Trastornos de la Memoria/diagnóstico por imagen , Persona de Mediana Edad , Fenotipo , Sistema de Registros
11.
Radiol Bras ; 54(4): 211-218, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34393286

RESUMEN

OBJECTIVE: To evaluate the performance of 1.5 T true fast imaging with steady state precession (TrueFISP) magnetic resonance imaging (MRI) sequences for the detection and characterization of pulmonary abnormalities caused by coronavirus disease 2019 (COVID-19). MATERIALS AND METHODS: In this retrospective single-center study, computed tomography (CT) and MRI scans of 20 patients with COVID-19 pneumonia were evaluated with regard to the distribution, opacity, and appearance of pulmonary lesions, as well as bronchial changes, pleural effusion, and thoracic lymphadenopathy. McNemar's test was used in order to compare the COVID-19-associated alterations seen on CT with those seen on MRI. RESULTS: Ground-glass opacities were better visualized on CT than on MRI (p = 0.031). We found no statistically significant differences between CT and MRI regarding the visualization/characterization of the following: consolidations; interlobular/intralobular septal thickening; the distribution or appearance of pulmonary abnormalities; bronchial pathologies; pleural effusion; and thoracic lymphadenopathy. CONCLUSION: Pulmonary abnormalities caused by COVID-19 pneumonia can be detected on TrueFISP MRI sequences and correspond to the patterns known from CT. Especially during the current pandemic, the portions of the lungs imaged on cardiac or abdominal MRI should be carefully evaluated to promote the identification and isolation of unexpected cases of COVID-19, thereby curbing further spread of the disease.


OBJETIVO: Avaliar o desempenho da ressonância magnética (RM) de 1,5 T true fast imaging with steady state precession (TrueFISP) para detecção e caracterização de anormalidades pulmonares causadas por doença do coronavírus 2019 (COVID-19). MATERIAIS E MÉTODOS: Neste estudo retrospectivo unicêntrico, imagens de tomografia computadorizada (TC) e RM de 20 pacientes com pneumonia COVID-19 foram avaliadas em relação a distribuição, opacidade e forma das lesões pulmonares, anormalidades brônquicas, derrame pleural e linfadenopatia torácica. O teste de McNemar foi usado para comparar os achados associados à COVID-19 na TC e na RM. RESULTADOS: As opacidades em vidro fosco foram mais bem visualizadas na TC do que na RM (p = 0,031). Não foram encontradas diferenças estatisticamente significantes entre TC e RM em relação aos outros aspectos, ou seja, visualização de consolidações e espessamento septal interlobular/intralobular, distribuição ou forma de anormalidades pulmonares, doenças brônquicas, derrame pleural ou linfadenopatia torácica. CONCLUSÃO: As anomalias pulmonares causadas pela pneumonia por COVID-19 podem ser detectadas nas sequências TrueFISP e correspondem aos padrões conhecidos da TC. Especialmente em face da pandemia atual, as porções de imagem dos pulmões na RM cardíaca ou abdominal devem ser cuidadosamente avaliadas para apoiar a identificação e o isolamento de casos inesperados de COVID-19 e, assim, conter a disseminação.

12.
J Pediatr Gastroenterol Nutr ; 73(5): 579-585, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34417399

RESUMEN

OBJECTIVES: A novel anti-regurgitation (AR) formula has been designed to support gut health and improve gastrointestinal (GI) symptoms beyond regurgitation. This study assessed the tolerance and safety of this new AR formula. METHODS: This was a 4-week double-blind, randomized, controlled trial with a 4-week extension in formula-fed infants with regurgitation. The new AR (Test) formula contained 0.4 g/100 mL locust bean gum (LBG) as thickener, partly fermented formula with postbiotics, and short-chain galacto-oligosaccharides (scGOS) and long-chain fructo-oligosaccharides (lcFOS) (0.4 g/100 mL, ratio 9:1). The Control AR formula contained LBG (0.4 g/100 mL) with postbiotics and has a history of safe use. The primary outcome was the Infant Gastrointestinal Symptom Questionnaire (IGSQ) sum score including stooling, spitting-up/vomiting, crying, fussiness and flatulence. RESULTS: All 182 infants screened were enrolled in the study. The primary analysis showed the equivalence of the IGSQ sum scores at Week 4 between groups. IGSQ sum scores improved significantly within 1 week (Mixed Model Repeated Measurement [MMRM], P < 0.001). Post-hoc analyses showed a bigger improvement of the IGSQ score in the Test (n = 38) versus Control (n = 44) group (MMRM, P = 0.008) in infants with more severe gastrointestinal (GI) symptoms (IGSQ score ≥35). Stool characteristics were comparable between groups. Growth related z scores were in line with the WHO child growth standards and both groups showed improvement of regurgitation. Adverse events did not show any safety concerns. CONCLUSIONS: The novel AR formula combining LBG, scGOS/lcFOS and postbiotics is well-tolerated, safe and supports adequate growth during the intervention. Post-hoc analyses suggest that the formula results in more improvement of GI symptom burden in infants with more severe symptoms.


Asunto(s)
Fórmulas Infantiles , Oligosacáridos , Llanto , Método Doble Ciego , Heces , Humanos , Lactante , Oligosacáridos/efectos adversos , Vómitos
13.
Radiol. bras ; 54(4): 211-218, July-Aug. 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1287744

RESUMEN

Abstract Objective: To evaluate the performance of 1.5 T true fast imaging with steady state precession (TrueFISP) magnetic resonance imaging (MRI) sequences for the detection and characterization of pulmonary abnormalities caused by coronavirus disease 2019 (COVID-19). Materials and Methods: In this retrospective single-center study, computed tomography (CT) and MRI scans of 20 patients with COVID-19 pneumonia were evaluated with regard to the distribution, opacity, and appearance of pulmonary lesions, as well as bronchial changes, pleural effusion, and thoracic lymphadenopathy. McNemar's test was used in order to compare the COVID-19-associated alterations seen on CT with those seen on MRI. Results: Ground-glass opacities were better visualized on CT than on MRI (p = 0.031). We found no statistically significant differences between CT and MRI regarding the visualization/characterization of the following: consolidations; interlobular/intralobular septal thickening; the distribution or appearance of pulmonary abnormalities; bronchial pathologies; pleural effusion; and thoracic lymphadenopathy. Conclusion: Pulmonary abnormalities caused by COVID-19 pneumonia can be detected on TrueFISP MRI sequences and correspond to the patterns known from CT. Especially during the current pandemic, the portions of the lungs imaged on cardiac or abdominal MRI should be carefully evaluated to promote the identification and isolation of unexpected cases of COVID-19, thereby curbing further spread of the disease.


Resumo Objetivo: Avaliar o desempenho da ressonância magnética (RM) de 1,5 T true fast imaging with steady state precession (TrueFISP) para detecção e caracterização de anormalidades pulmonares causadas por doença do coronavírus 2019 (COVID-19). Materiais e Métodos: Neste estudo retrospectivo unicêntrico, imagens de tomografia computadorizada (TC) e RM de 20 pacientes com pneumonia COVID-19 foram avaliadas em relação a distribuição, opacidade e forma das lesões pulmonares, anormalidades brônquicas, derrame pleural e linfadenopatia torácica. O teste de McNemar foi usado para comparar os achados associados à COVID-19 na TC e na RM. Resultados: As opacidades em vidro fosco foram mais bem visualizadas na TC do que na RM (p = 0,031). Não foram encontradas diferenças estatisticamente significantes entre TC e RM em relação aos outros aspectos, ou seja, visualização de consolidações e espessamento septal interlobular/intralobular, distribuição ou forma de anormalidades pulmonares, doenças brônquicas, derrame pleural ou linfadenopatia torácica. Conclusão: As anomalias pulmonares causadas pela pneumonia por COVID-19 podem ser detectadas nas sequências TrueFISP e correspondem aos padrões conhecidos da TC. Especialmente em face da pandemia atual, as porções de imagem dos pulmões na RM cardíaca ou abdominal devem ser cuidadosamente avaliadas para apoiar a identificação e o isolamento de casos inesperados de COVID-19 e, assim, conter a disseminação.

14.
Reprod Biomed Online ; 42(4): 789-798, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33658156

RESUMEN

RESEARCH QUESTION: Are there genetic determinants shared by unrelated women with unexplained recurrent early miscarriage (REM)? DESIGN: Thirty REM cases and 30 controls were selected with extreme phenotype among women from Eastern Brittany (France), previously enrolled in an incident case-control study on thrombophilic mutations. Cases and controls were selected based on the number of early miscarriages or live births, respectively. Peripheral blood was collected for DNA extraction at initial visit. The burden of low-frequency variants in the coding part of the genes was compared using whole exome sequencing (WES). RESULTS: Cases had 3 to 17 early miscarriages (20 cases: ≥5 previous losses). Controls had 1 to 4 live births (20 controls: ≥3 previous live births) and no miscarriages. WES data were available for 29 cases and 30 controls. A total of 209,387 variants were found (mean variant per patient: 59,073.05) with no difference between groups (P = 0.68). The top five most significantly associated genes were ABCA4, NFAM1, TCN2, AL078585.1 and EPS15. Previous studies suggest the involvement of vitamin B12 deficiency in REM. TCN2 encodes for vitamin B12 transporter into cells. Therefore, holotranscobalamin (active vitamin B12) was measured for both cases and controls (81.2 ± 32.1 versus 92.9 ± 34.3 pmol/l, respectively, P = 0.186). Five cases but no controls were below 50 pmol/l (P = 0.052). CONCLUSIONS: This study highlights four new genes of interest in REM, some of which belong to known networks of genes involved in embryonic development (clathrin-mediated endocytosis and ciliary pathway). The study also confirms the involvement of TCN2 (vitamin B12 pathway) in the early first trimester of pregnancy.


Asunto(s)
Aborto Habitual/genética , Secuenciación del Exoma , Aborto Habitual/sangre , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Embarazo , Transcobalaminas/genética , Deficiencia de Vitamina B 12/complicaciones , Adulto Joven
15.
J Phys Chem Lett ; 12(11): 2954-2962, 2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33729797

RESUMEN

In heterogeneous catalysis, free energy profiles of reactions govern the mechanisms, rates, and equilibria. Energetics are conventionally computed using the harmonic approximation (HA), which requires determination of critical states a priori. Here, we use neural networks to efficiently sample and directly calculate the free energy surface (FES) of a prototypical heterogeneous catalysis reaction-the dissociation of molecular nitrogen on ruthenium-at density-functional-theory-level accuracy. We find that the vibrational entropy of surface atoms, often neglected in HA for transition metal catalysts, contributes significantly to the reaction barrier. The minimum free energy path for dissociation reveals an "on-top" adsorbed molecular state prior to the transition state. While a previously reported flat-lying molecular metastable state can be identified in the potential energy surface, it is absent in the FES at relevant reaction temperatures. These findings demonstrate the importance of identifying critical points self-consistently on the FES for reactions that involve considerable entropic effects.

16.
J Pediatr Gastroenterol Nutr ; 72(2): 255-261, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33275399

RESUMEN

BACKGROUND/AIMS: Accurate stool consistency classification of non-toilet-trained children remains challenging. This study evaluated the feasibility of automated classification of stool consistencies from diaper photos using machine learning (ML). METHODS: In total, 2687 usable smartphone photos of diapers with stool from 96 children younger than 24 months were obtained after independent ethical study approval. Stool consistency was assessed from each photo according to the original 7 types of the Brussels Infant and Toddler Stool Scale independently by study participants and 2 researchers. A health care professional assigned a final score in case of scoring disagreement between the researchers. A proof-of-concept ML model was built upon this collected photo database, using transfer learning to re-train the classification layer of a pretrained deep convolutional neural network model. The model was built on random training (n = 2478) and test (n = 209) subsets. RESULTS: Agreements between study participants and both researchers were 58.0% and 48.5%, respectively, and between researchers 77.5% (assessable n = 2366). The model classified 60.3% of the test photos in exact agreement with the final score. With respect to the 4-class grouping of the 7 Brussels Infant and Toddler Stool Scale types, the agreement between model-based and researcher classification was 77.0%. CONCLUSION: The automated and objective scoring of stool consistency from diaper photos by the ML model shows robust agreement with human raters and overcomes limitations of other methods relying on caregiver reporting. Integrated with a smartphone application, this new framework for photo database construction and ML classification has numerous potential applications in clinical studies and home assessment.


Asunto(s)
Aprendizaje Automático , Redes Neurales de la Computación , Niño , Bases de Datos Factuales , Heces , Humanos , Lactante , Cuidado del Lactante
17.
J Phys Chem Lett ; 11(22): 9802-9811, 2020 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-33151694

RESUMEN

Acetonitrile is among the most commonly used nonaqueous solvents in catalysis and electrochemistry. We study its interfaces with multiple facets of the metals Ag, Cu, Pt, and Rh using density functional theory calculations; the structures reported shed new light on experimental observations and underscore the importance of solvent-solvent interactions at high coverage. We investigate the relationship of potential of zero charge (PZC) to metal work function, reporting results in agreement with experimental measurements. We develop a model to explain the effects of solvent chemisorption and orientation on the PZC to within a mean absolute deviation of 0.08-0.12 V for all facets studied. Our electrostatic field dependent phase diagram agrees with spectroscopic observations and sheds new light on electrostatic field effects. This work provides new insight into experimental observations on acetonitrile metal interfaces and provides guidance for future studies of acetonitrile and other nonaqueous solvent interfaces with transition metals.

18.
Cancer Res ; 80(19): 4172-4184, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32732220

RESUMEN

Heterozygous mutations in the BRCA1 gene predispose women to breast and ovarian cancer, while biallelic BRCA1 mutations are a cause of Fanconi anemia (FA), a rare genetic disorder characterized by developmental abnormalities, early-onset bone marrow failure, increased risk of cancers, and hypersensitivity to DNA-crosslinking agents. BRCA1 is critical for homologous recombination of DNA double-strand breaks (DSB). Through its coiled-coil domain, BRCA1 interacts with an essential partner, PALB2, recruiting BRCA2 and RAD51 to sites of DNA damage. Missense mutations within the coiled-coil domain of BRCA1 (e.g., L1407P) that affect the interaction with PALB2 have been reported in familial breast cancer. We hypothesized that if PALB2 regulates or mediates BRCA1 tumor suppressor function, ablation of the BRCA1-PALB2 interaction may also elicit genomic instability and tumor susceptibility. We generated mice defective for the Brca1-Palb2 interaction (Brca1 L1363P in mice) and established MEF cells from these mice. Brca1 L1363P/L1363P MEF exhibited hypersensitivity to DNA-damaging agents and failed to recruit Rad51 to DSB. Brca1 L1363P/L1363P mice were viable but exhibited various FA symptoms including growth retardation, hyperpigmentation, skeletal abnormalities, and male/female infertility. Furthermore, all Brca1 L1363P/L1363P mice exhibited macrocytosis and died due to bone marrow failure or lymphoblastic lymphoma/leukemia with activating Notch1 mutations. These phenotypes closely recapitulate clinical features observed in patients with FA. Collectively, this model effectively demonstrates the significance of the BRCA1-PALB2 interaction in genome integrity and provides an FA model to investigate hematopoietic stem cells for mechanisms underlying progressive failure of hematopoiesis and associated development of leukemia/lymphoma, and other FA phenotypes. SIGNIFICANCE: A new Brca1 mouse model for Fanconi anemia (FA) complementation group S provides a system in which to study phenotypes observed in human FA patients including bone marrow failure.See related commentary by Her and Bunting, p. 4044.


Asunto(s)
Neoplasias de la Mama , Anemia de Fanconi , Animales , Proteína BRCA1/genética , Daño del ADN/genética , Anemia de Fanconi/genética , Proteína del Grupo de Complementación N de la Anemia de Fanconi/genética , Femenino , Humanos , Masculino , Ratones , Fenotipo , Proteínas Supresoras de Tumor/genética
19.
Phys Chem Miner ; 47(5): 24, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32390681

RESUMEN

In this study, we present the first systematic dataset on natural variations of OH defect and trace element contents in quartz within igneous bodies. Samples were derived from bore holes of two plutonic bodies from the Krusné Hory/Erzgebirge (German-Czech border), representing typical A-type (Cínovec/Zinnwald granite cupola) and S-type (Podlesí Stock) granite intrusions. Fourier Transform Infrared spectroscopy of quartz was used to investigate the sample set with regard to its OH defect speciation and content. For Zinnwald quartz, IR absorption spectra reveal different lithologies due to changes of the OH defect inventory, enabling a subdivision of the granitic body: (1) hydrothermal greisen quartz of the uppermost part of the intrusion have low OH defect contents (average of 15 µg/g H2O); (2) zinnwaldite granite quartz vary strongly in defect content and show the highest content of the dataset (10-70 µg/g H2O); (3) quartz from an underlying biotite granite have slightly lower, but very uniform contents down to the bottom of the borehole at 1600 m (average 20 µg/g H2O). Infrared spectra of Podlesí quartz reveal a gradual increase in total defect water content with increasing depth over 350 m (30-55 µg/g H2O). Lithium contents in quartz samples from the uppermost part of the Zinnwald intrusion correlate with the occurrence of Li-specific OH defects, while cathodoluminescence (CL) images do not show specific differences. Our findings evidence the potential of OH defects in quartz as a tool to decipher differentiation trends in igneous bodies, and the application of their eroded material for provenance analyses.

20.
J Chem Phys ; 152(14): 144703, 2020 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-32295363

RESUMEN

Determining the influence of the solvent on electrochemical reaction energetics is a central challenge in our understanding of electrochemical interfaces. To date, it is unclear how well existing methods predict solvation energies at solid/liquid interfaces, since they cannot be assessed experimentally. Ab initio molecular dynamics (AIMD) simulations present a physically highly accurate, but also a very costly approach. In this work, we employ extensive AIMD simulations to benchmark solvation at charge-neutral metal/water interfaces against commonly applied continuum solvent models. We consider a variety of adsorbates including *CO, *CHO, *COH, *OCCHO, *OH, and *OOH on Cu, Au, and Pt facets solvated by water. The surfaces and adsorbates considered are relevant, among other reactions, to electrochemical CO2 reduction and the oxygen redox reactions. We determine directional hydrogen bonds and steric water competition to be critical for a correct description of solvation at the metal/water interfaces. As a consequence, we find that the most frequently applied continuum solvation methods, which do not yet capture these properties, do not presently provide more accurate energetics over simulations in vacuum. We find most of the computed benchmark solvation energies to linearly scale with hydrogen bonding or competitive water adsorption, which strongly differ across surfaces. Thus, we determine solvation energies of adsorbates to be non-transferable between metal surfaces, in contrast to standard practice.

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