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1.
Mol Neurobiol ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261388

RESUMEN

The most common cause of dementia among elderly people is Alzheimer's disease (AD). The typical symptom of AD is the decline of cognitive abilities, which is caused by loss of synaptic function. Amyloid-ß (Aß) oligomers play a significant role in the development of this synaptic dysfunction. Neuroligin-(NL)1 is a postsynaptic cell-adhesion molecule located in excitatory synapses and involved in the maintenance and modulation of synaptic contacts. A recent study has found that Aß interacts with the soluble N-terminal fragment of NL1. The present study aimed to elucidate the role of NL1 in Aß-induced neuropathology. Employing surface plasmon resonance and competitive ELISA, we confirmed the high-affinity binding of NL1 to the Aß peptide. We also identified a sequence motif representing the NL1-binding site for the Aß peptide and showed that a synthetic peptide modeled after this motif, termed neurolide, binds to the Aß peptide with high affinity, comparable to the NL1-Aß interaction. To assess the effect of neurolide in vivo, wild-type and 5XFAD mice were subcutaneously treated with this peptide for 10 weeks. We observed an increase in Aß plaque formation in the cortex of neurolide-treated 5XFAD mice. Furthermore, we showed that neurolide reduces the activity of neprilysin, the predominant Aß-degrading enzyme in the brain. Accordingly, we suggest that neurolide is the NL1-binding site for Aß peptide, and acts as an inhibitor of neprilysin activity. Based on these data, we confirm the involvement of NL1 in the development of AD and suggest a mechanism for NL1-induced Aß plaque formation.

2.
Qual Life Res ; 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39174866

RESUMEN

PURPOSE: The minimal important change (MIC) in a patient-reported outcome measure is often estimated using patient-reported transition ratings as anchor. However, transition ratings are often more heavily weighted by the follow-up state than by the baseline state, a phenomenon known as "present state bias" (PSB). It is unknown if and how PSB affects the estimation of MICs using various methods. METHODS: We simulated 3240 samples in which the true MIC was simulated as the mean of individual MICs, and PSB was created by basing transition ratings on a "weighted change", differentially weighting baseline and follow-up states. In each sample we estimated MICs based on the following methods: mean change (MC), receiver operating characteristic (ROC) analysis, predictive modeling (PM), adjusted predictive modeling (APM), longitudinal item response theory (LIRT), and longitudinal confirmatory factor analysis (LCFA). The latter two MICs were estimated with and without constraints on the transition item slope parameters (LIRT) or factor loadings (LCFA). RESULTS: PSB did not affect MIC estimates based on MC, ROC, and PM but these methods were biased by other factors. PSB caused imprecision in the MIC estimates based on APM, LIRT and LCFA with constraints, if the degree of PSB was substantial. However, the unconstrained LIRT- and LCFA-based MICs recovered the true MIC without bias and with high precision, independent of the degree of PSB. CONCLUSION: We recommend the unconstrained LIRT- and LCFA-based MIC methods to estimate anchor-based MICs, irrespective of the degree of PSB. The APM-method is a feasible alternative if PSB is limited.

3.
Gastrointest Endosc ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38908453

RESUMEN

BACKGROUND AND AIMS: Implementation of screening modalities have reduced the burden of colorectal cancer (CRC), but high false positive rates pose a major problem for colonoscopy capacity. We aimed to create a tailored screening algorithm that expands the fecal immunochemical test (FIT) with a blood specimen and current age to improve selection of individuals for diagnostic colonoscopy. METHODS: In this prospective multicenter study, 8 blood-based biomarkers (carcinoembryonic antigen, ferritin, high-sensitivity C-reactive protein, human epididymis protein 4, Cyfra21-1, hepsin, interleukin 8, and osteoprotegerin) were investigated in 1977 FIT-positive individuals from the Danish national CRC screening program undergoing follow-up colonoscopy. Specimens were analyzed on Architect i2000, Architect c8000 (both from Abbott, Chicago, IL, USA), or Luminex xMAP machines (MilliporeSigma, St. Louis, Mo, USA). FIT analyses and blood-based biomarker data were combined with clinical data (ie, age and colonoscopy findings) in a cross-validated logistic regression model (algorithm) benchmarked against a model solely using the FIT result (FIT model) applying different cutoffs for FIT positivity. RESULTS: The cohort included individuals with CRC (n = 240), adenomas (n = 938), or no neoplastic lesions (n = 799). The cross-validated algorithm combining the 8 biomarkers, quantitative FIT result, and age performed superior to the FIT model in discriminating CRC versus non-CRC individuals (area under the receiver operating characteristic curve, 0.77 vs 0.67, respectively; P < .001). When discriminating individuals with either CRC or high- or medium-risk adenomas versus low-risk adenomas or clean colorectum, the areas under the receiver operating characteristic curve were 0.68 versus 0.64 for the algorithm and FIT model, respectively. CONCLUSIONS: The algorithm presented here can improve patient allocation to colonoscopy, reducing colonoscopy burden without compromising cancer and adenoma detection rates or vice versa.

4.
Eur J Cardiothorac Surg ; 65(6)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38837348

RESUMEN

OBJECTIVES: To assess the accuracy of a deep learning-based algorithm for fully automated detection of thoracic aortic calcifications in chest computed tomography (CT) with a focus on the aortic clamping zone. METHODS: We retrospectively included 100 chest CT scans from 91 patients who were examined on second- or third-generation dual-source scanners. Subsamples comprised 47 scans with an electrocardiogram-gated aortic angiography and 53 unenhanced scans. A deep learning model performed aortic landmark detection and aorta segmentation to derive 8 vessel segments. Associated calcifications were detected and their volumes measured using a mean-based density thresholding. Algorithm parameters (calcium cluster size threshold, aortic mask dilatation) were varied to determine optimal performance for the upper ascending aorta that encompasses the aortic clamping zone. A binary visual rating served as a reference. Standard estimates of diagnostic accuracy and inter-rater agreement using Cohen's Kappa were calculated. RESULTS: Thoracic aortic calcifications were observed in 74% of patients with a prevalence of 27-70% by aorta segment. Using different parameter combinations, the algorithm provided binary ratings for all scans and segments. The best performing parameter combination for the presence of calcifications in the aortic clamping zone yielded a sensitivity of 93% and a specificity of 82%, with an area under the receiver operating characteristic curve of 0.874. Using these parameters, the inter-rater agreement ranged from κ 0.66 to 0.92 per segment. CONCLUSIONS: Fully automated segmental detection of thoracic aortic calcifications in chest CT performs with high accuracy. This includes the critical preoperative assessment of the aortic clamping zone.


Asunto(s)
Aorta Torácica , Enfermedades de la Aorta , Aprendizaje Profundo , Tomografía Computarizada por Rayos X , Calcificación Vascular , Humanos , Aorta Torácica/diagnóstico por imagen , Estudios Retrospectivos , Femenino , Masculino , Calcificación Vascular/diagnóstico por imagen , Anciano , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Enfermedades de la Aorta/diagnóstico por imagen , Algoritmos , Anciano de 80 o más Años
5.
JACC Adv ; 3(3): 100829, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38938835

RESUMEN

Background: Left ventricular noncompaction (LVNC) is characterized by excessive trabeculations of the left ventricular (LV) wall. Objectives: The authors aimed to examine changes in LV function and morphology in 2 to 4-year-old children with and without LVNC at birth and to describe the prevalence of LVNC in first-degree relatives. Methods: Echocardiograms in children with and without LVNC (matched 1:4) were performed at 2 to 4 years and in first-degree relatives. LVNC was blindly assessed and defined as a ratio of non-compact to compact myocardium of ≥2 in ≥1 LV segment. Trabeculations were expressed as a percentage of the number of segments with LVNC out of the total number of segments. Results: In total, 14 (median age 3 years, 71% male) of 16 children with LVNC at birth and 56 children without (median age 4 years, 71% male), 37 first-degree relatives of children with LVNC (median age 31 years, 46% male) and 146 first-degree relatives of children without (median age 33 years, 50% male) were included. In children with LVNC, trabeculation (8% vs 13%, P = 0.81) and LV ejection fraction (50% vs 49%, P = 0.91) were unchanged from birth to follow-up but LV ejection fraction was lower compared to children without LVNC (49% vs 60%, P < 0.001). In relatives of children with LVNC, 11 of 37 (30%) fulfilled LVNC criteria compared to no relatives to children without LVNC (P < 0.001). Conclusions: At 2 to 4 years, children with LVNC diagnosed at birth had reduced systolic function compared to children without but did not have progression of LV dysfunction or extent of trabeculations. In first-degree relatives to children with LVNC, 30% fulfilled criteria.

6.
J Crohns Colitis ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38940464

RESUMEN

BACKGROUND AND AIMS: Reliable and easily accessible objective markers of disease activity to predict long-term treatment outcomes in severe ulcerative colitis (UC) are missing. We aimed to investigate if intestinal ultrasound (IUS) might predict long-term outcomes in hospitalized patients with severe UC treated with intravenous corticosteroids. METHODS: Hospitalized patients with severe UC and IUS inflammation (bowel wall thickness (BWT)>3.0mm) starting IV corticosteroids were recruited at three university hospitals in Denmark. IUS was performed before treatment, 48±24 hours (h), 6±1 days, and 3 months after treatment initiation. Time until colectomy or need for new interventions was registered together with Mayo score at 3 months and partial Mayo score (pMayo) at 12-months. Follow-up time was 12 months. RESULTS: Fifty-six patients were included in the final analysis. Forty-five (80%) patients needed intervention, including 9 colectomies, during the 12-month follow-up. After 48±24h: No patient with a BWT<3mm needed a colectomy, p=0.04. BWT≥4mm showed an increased risk of colectomy (odds ratio 9.5 (95%CI 1.5-186), p=0.03), while a BWT≥3mm showed an increased risk of intervention (3.6 (1.1-12.5), p=0.03). A BWT≥4mm resulted in a significantly shorter time until both colectomy, p=0.03, and treatment intensification (mean days 75 (95%CI24-127) vs. 176 (119-233), p=0.005. However, neither IUS parameters nor pMayo score, CRP, hemoglobin, or p-albumin could predict remission at 3- and 12-months. CONCLUSION: BWT assessed at 48h post intravenous corticosteroid initiation in patients hospitalized with severe UC may identify patients with an increased risk of short- and long-term colectomy and predict a more aggressive short-term disease course.

7.
J Crohns Colitis ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38899778

RESUMEN

BACKGROUND AND AIMS: To demonstrate that administration of 7500 Trichuris suis ova every second week over 24 weeks would reduce the intestinal inflammation in moderate ulcerative colitis. METHODS: A single-centre, randomized, double-blinded, placebo-controlled, phase 2b clinical trial of 7500 Trichuris suis ova every two weeks for 24 weeks compared to placebo in moderate activity of ulcerative colitis (Mayo score 6-10) were performed. Primary outcome: Clinical remission. Secondary outcomes: Clinical response at 24 weeks, complete corticosteroid-free clinical remission, endoscopic remission, symptomatic remission at 12 and 24 weeks and partial Mayo score over time. RESULTS: 119 patients were randomized to Trichuris suis ova (n=60) and placebo (n=59). At week 24, clinical remission was achieved in 30% of Trichuris suis ova-treated vs. 34% of placebo-treated (RR=0.89; CI:0.52-1.50; p=0.80, ITT). No difference was found in clinical response in any of the clinical response subgroups. However, in patients who did not need treatment with corticosteroids during the trial, a temporary effect of TSO was seen in the analysis of symptomatic remission of week 12 (p=0.01), and the partial Mayo score at week 14 and week 18 (p<0.05 and p=0.02). CONCLUSIONS: Compared to placebo, Trichuris suis ova was not superior in achieving clinical remission at week 24 in ulcerative colitis or in achieving clinical Mayo score reduction, complete corticosteroid-free clinical remission or endoscopic remission. However, Trichuris suis ova treatment induced symptomatic temporary remission at week 12.

8.
Diabetes Obes Metab ; 26(7): 2945-2955, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38698650

RESUMEN

AIMS: To summarize the effects of semaglutide 2.4 mg on weight-related quality of life (WRQOL) and health-related quality of life (HRQOL), focusing on the confirmatory secondary endpoint of physical functioning. MATERIALS AND METHODS: The STEP 1-4 Phase 3a, 68-week, double-blind, randomized controlled trials assessed the efficacy and safety of semaglutide 2.4 mg versus placebo in individuals with overweight/obesity. WRQOL and HRQOL were assessed by change from baseline to Week 68 in two different but complementary measures, the Impact of Weight on Quality of Life-Lite Clinical Trials Version (IWQOL-Lite-CT; STEP 1 and 2) and the SF-36v2 Health Survey Acute (SF-36v2; STEP 1-4). RESULTS: Superiority for semaglutide 2.4 mg over placebo based on IWQOL-Lite-CT and SF-36v2 physical functioning scores was confirmed in STEP 1 and 2 and in STEP 1, 2 and 4, respectively. At Week 68, a greater proportion of participants treated with semaglutide 2.4 mg than with placebo reached meaningful within-person change (MWPC) thresholds for IWQOL-Lite-CT Physical Function scores in STEP 1 (51.8% vs. 28.3%; p < 0.0001) and STEP 2 (39.6% vs. 29.5%; p = 0.0083) and the MWPC threshold for SF-36v2 Physical Functioning in STEP 1 (39.8% vs. 24.1%; p < 0.0001), STEP 2 (41.0% vs. 27.3%; p = 0.0001) and STEP 4 (18.0% vs. 6.6%; p < 0.0001). All other IWQOL-Lite-CT and SF-36v2 scale scores in STEP 1-4 were numerically improved with semaglutide 2.4 mg versus placebo, except for SF-36v2 Role Emotional in STEP 2. CONCLUSIONS: Semaglutide 2.4 mg significantly improved physical functioning, with greater proportions of participants achieving MWPC compared with placebo, and showed beneficial effects on WRQOL and HRQOL beyond physical functioning.


Asunto(s)
Péptidos Similares al Glucagón , Obesidad , Sobrepeso , Medición de Resultados Informados por el Paciente , Calidad de Vida , Humanos , Péptidos Similares al Glucagón/uso terapéutico , Masculino , Femenino , Persona de Mediana Edad , Método Doble Ciego , Adulto , Obesidad/tratamiento farmacológico , Obesidad/psicología , Sobrepeso/tratamiento farmacológico , Pérdida de Peso/efectos de los fármacos , Hipoglucemiantes/uso terapéutico
9.
J Crohns Colitis ; 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38727089

RESUMEN

BACKGROUND AND AIMS: Despite advances in the medical treatment of Crohn's disease (CD), many patients will still need bowel resections and face the subsequent risk of recurrence and re-resection. We describe contemporary re-resection rates and identify disease-modifying factors and risk factors for re-resection. METHODS: We conducted a retrospective, population-based, individual patient data cohort study covering 47.4% of the Danish population, including all CD patients who underwent a primary resection between 2010 and 2020. RESULTS: Among 631 primary resected patients, 24.5% underwent a second resection, and 5.3% a third. Re-resection rates after one, five, and 10 years were 12.6%, 22.4%, and 32.2%, respectively. Reasons for additional resections were mainly disease activity (57%) and stoma reversal (40%). Disease activity-driven re-resection rates after one, five, and 10 years were 3.6%, 10.1%, and 14.1%, respectively. Most stoma reversals occurred within one year (80%). The median time to recurrence was 11.0 months. Biologics started within one year of the first resection revealed protective effect against re-resection for stenotic and penetrating phenotypes. Prophylactic biologic therapy at primary ileocecal resection reduced disease recurrence and re-resection risk (HR 0.58, 95% CI (0.34-0.99), p=0.047). Risk factors for re-resection were location of resected bowel segments at the primary resection, disease location, disease behavior, smoking, and perianal disease. CONCLUSION: Re-resection rates, categorized by disease activity, are lower than those reported in other studies and are closely associated with disease phenotype and localization. Biological therapy may be disease-modifying for certain subgroups when initiated within one year of resection.

10.
Am J Physiol Gastrointest Liver Physiol ; 327(1): G70-G79, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38713614

RESUMEN

Although impaired regeneration is important in many gastrointestinal diseases including ulcerative colitis (UC), the dynamics of mucosal regeneration in humans are poorly investigated. We have developed a model to study these processes in vivo in humans. Epithelial restitution (ER) and extracellular matrix (ECM) regulation after an experimental injury of the sigmoid colonic mucosa was assessed by repeated high-resolution endoscopic imaging, histological assessment, RNA sequencing, deconvolution analysis, and 16S rDNA sequencing of the injury niche microbiome of 19 patients with UC in remission and 20 control subjects. Human ER had a 48-h lag before induction of regenerative epithelial cells [wound-associated epithelial (WAE) and transit amplifying (TA) cells] along with the increase of fibroblast-derived stem cell growth factor gremlin 1 mRNA (GREM1). However, UC deconvolution data showed rapid induction of inflammatory fibroblasts and upregulation of major structural ECM collagen mRNAs along with tissue inhibitor of metalloproteinase 1 (TIMP1), suggesting increased profibrotic ECM deposition. No change was seen in transforming growth factor ß (TGFß) mRNA, whereas the profibrotic cytokines interleukin 13 (IL13) and IL11 were upregulated in UC, suggesting that human postinjury responses could be TGFß-independent. In conclusion, we found distinct regulatory layers of regeneration in the normal human colon and a potential targetable profibrotic dysregulation in UC that could lead to long-term end-organ failure, i.e., intestinal damage.NEW & NOTEWORTHY The study reveals the regulatory dynamics of epithelial regeneration and extracellular matrix remodeling after experimental injury of the human colon in vivo and shows that human intestinal regeneration is different from data obtained from animals. A lag phase in epithelial restitution is associated with induction of stromal cell-derived epithelial growth factors. Postinjury regeneration is transforming growth factor ß-independent, and we find a profibrotic response in patients with ulcerative colitis despite being in remission.


Asunto(s)
Colitis Ulcerosa , Mucosa Intestinal , Transducción de Señal , Factor de Crecimiento Transformador beta , Humanos , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/patología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Masculino , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta/genética , Femenino , Adulto , Matriz Extracelular/metabolismo , Persona de Mediana Edad , Regeneración , Fibrosis , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Péptidos y Proteínas de Señalización Intercelular/genética , Células Epiteliales/metabolismo , Cicatrización de Heridas , Colon Sigmoide/metabolismo , Colon Sigmoide/patología , Fibroblastos/metabolismo
11.
J Am Heart Assoc ; 13(8): e033287, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38563363

RESUMEN

BACKGROUND: We aimed to correlate alterations in the rat sarcoma virus (RAS)/mitogen-activated protein kinase pathway in vascular anomalies to the clinical phenotype for improved patient and treatment stratification. METHODS AND RESULTS: This retrospective multicenter cohort study included 29 patients with extracranial vascular anomalies containing mosaic pathogenic variants (PVs) in genes of the RAS/mitogen-activated protein kinase pathway. Tissue samples were collected during invasive treatment or clinically indicated biopsies. PVs were detected by the targeted sequencing of panels of genes known to be associated with vascular anomalies, performed using DNA from affected tissue. Subgroup analyses were performed according to the affected genes with regard to phenotypic characteristics in a descriptive manner. Twenty-five vascular malformations, 3 vascular tumors, and 1 patient with both a vascular malformation and vascular tumor presented the following distribution of PVs in genes: Kirsten rat sarcoma viral oncogene (n=10), neuroblastoma ras viral oncogene homolog (n=1), Harvey rat sarcoma viral oncogene homolog (n=5), V-Raf murine sarcoma viral oncogene homolog B (n=8), and mitogen-activated protein kinase kinase 1 (n=5). Patients with RAS PVs had advanced disease stages according to the Schobinger classification (stage 3-4: RAS, 9/13 versus non-RAS, 3/11) and more frequent progression after treatment (RAS, 10/13 versus non-RAS, 2/11). Lesions with Kirsten rat sarcoma viral oncogene PVs infiltrated more tissue layers compared with the other PVs including other RAS PVs (multiple tissue layers: Kirsten rat sarcoma viral oncogene, 8/10 versus other PVs, 6/19). CONCLUSIONS: This comparison of patients with various PVs in genes of the RAS/MAPK pathway provides potential associations with certain morphological and clinical phenotypes. RAS variants were associated with more aggressive phenotypes, generating preliminary data and hypothesis for future larger studies.


Asunto(s)
Proteínas Proto-Oncogénicas p21(ras) , Malformaciones Vasculares , Humanos , Estudios de Cohortes , Estudios de Asociación Genética , Proteínas Quinasas Activadas por Mitógenos/genética , Mutación , Malformaciones Vasculares/genética
13.
Malar J ; 23(1): 100, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589884

RESUMEN

BACKGROUND: Anopheles gambiae, the major malaria mosquito in sub-Saharan Africa, feed largely indoors at night. Raising a house off the ground with no barriers underneath reduces mosquito-house entry. This experiment tested whether walling off the space under an elevated hut affects mosquito-hut entry. METHODS: Four inhabited experimental huts, each of which could be moved up and down, were used in rural Gambia. Nightly collections of mosquitoes were made using light traps and temperature and carbon dioxide levels monitored indoors and outdoors using loggers. Each night, a reference hut was kept at ground level and three huts raised 2 m above the ground; with the space under the hut left open, walled with air-permeable walls or solid walls. Treatments were rotated every four nights using a randomized block design. The experiment was conducted for 32 nights. Primary measurements were mosquito numbers and indoor temperature in each hut. RESULTS: A total of 1,259 female Anopheles gambiae sensu lato were collected in the hut at ground level, 655 in the hut with an open ground floor, 981 in the hut with air-permeable walls underneath and 873 in the hut with solid walls underneath. Multivariate analysis, adjusting for confounders, showed that a raised hut open underneath had 53% fewer mosquitoes (95% CI 47-58%), those with air-permeable walls underneath 24% fewer (95% CI 9-36%) and huts with solid walls underneath 31% fewer (95% CI 24-37%) compared with a hut on the ground. Similar results were found for Mansonia spp. and total number of female mosquitoes, but not for Culex mosquitoes where hut entry was unaffected by height or barriers. Indoor temperature and carbon dioxide levels were similar in all huts. CONCLUSION: Raising a house 2 m from the ground reduces the entry of An. gambiae and Mansonia mosquitoes, but not Culex species. The protective effect of height is reduced if the space underneath the hut is walled off.


Asunto(s)
Anopheles , Culex , Insecticidas , Animales , Femenino , Gambia , Dióxido de Carbono/farmacología , Control de Mosquitos/métodos , Mosquitos Vectores , Insecticidas/farmacología
14.
Nature ; 629(8010): 92-97, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38503346

RESUMEN

Ammonia is crucial as a fertilizer and in the chemical industry and is considered to be a carbon-free fuel1. Ammonia electrosynthesis from nitrogen under ambient conditions offers an attractive alternative to the Haber-Bosch process2,3, and lithium-mediated nitrogen reduction represents a promising approach to continuous-flow ammonia electrosynthesis, coupling nitrogen reduction with hydrogen oxidation4. However, tetrahydrofuran, which is commonly used as a solvent, impedes long-term ammonia production owing to polymerization and volatility problems. Here we show that a chain-ether-based electrolyte enables long-term continuous ammonia synthesis. We find that a chain-ether-based solvent exhibits non-polymerization properties and a high boiling point (162 °C) and forms a compact solid-electrolyte interphase layer on the gas diffusion electrode, facilitating ammonia release in the gas phase and ensuring electrolyte stability. We demonstrate 300 h of continuous operation in a flow electrolyser with a 25 cm2 electrode at 1 bar pressure and room temperature, and achieve a current-to-ammonia efficiency of 64 ± 1% with a gas-phase ammonia content of approximately 98%. Our results highlight the crucial role of the solvent in long-term continuous ammonia synthesis.

15.
Front Plant Sci ; 15: 1359226, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38476691

RESUMEN

Introduction: The seeds of wild pea (Pisum) exhibit marked physical dormancy due to impermeability of the seed coat to water, and the loss of this dormancy is thought to have been critical for domestication. Wild pea seed coats are also notably thick and rough, traits that have also reduced during domestication and are anecdotally linked to increased permeability. However, how these traits specifically interact with permeability is unclear. Methods: To investigate this, we examined the genetic control of differences in seed coat characteristics between wild P. sativum ssp. humile and a non-dormant domesticated P. s. sativum accession in a recombinant inbred population. QTL effects were confirmed and their locations refined in segregating F4/5 populations. Results: In this population we found a moderate correlation between testa thickness and permeability, and identified loci that affect them independently, suggesting no close functional association. However, the major loci affecting both testa thickness and permeability collocated closely with Mendel's pigmentation locus A, suggesting flavonoid compounds under its control might contribute significantly to both traits. We also show that seed coat roughness is oligogenic in this population, with the major locus independent of both testa thickness and permeability, suggesting selection for smooth seed was unlikely to be due to effects on either of these traits. Discussion: Results indicate loss of seed coat dormancy during domestication was not primarily driven by reduced testa thickness or smooth seededness. The close association between major permeability and thickness QTL and Mendel's 'A' warrant further study, particularly regarding the role of flavonoids.

16.
Nat Commun ; 15(1): 2417, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499554

RESUMEN

Ammonia is a crucial component in the production of fertilizers and various nitrogen-based compounds. Now, the lithium-mediated nitrogen reduction reaction (Li-NRR) has emerged as a promising approach for ammonia synthesis at ambient conditions. The proton shuttle plays a critical role in the proton transfer process during Li-NRR. However, the structure-activity relationship and design principles for effective proton shuttles have not yet been established in practical Li-NRR systems. Here, we propose a general procedure for verifying a true proton shuttle and established design principles for effective proton shuttles. We systematically evaluate several classes of proton shuttles in a continuous-flow reactor with hydrogen oxidation at the anode. Among the tested proton shuttles, phenol exhibits the highest Faradaic efficiency of 72 ± 3% towards ammonia, surpassing that of ethanol, which has been commonly used so far. Experimental investigations including operando isotope-labelled mass spectrometry proved the proton-shuttling capability of phenol. Further mass transport modeling sheds light on the mechanism.

17.
Kidney Med ; 6(1): 100755, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38192435

RESUMEN

Rationale & Objective: Using OVERTURE (NCT01430494) study data on patient-perceived health, health care utilization, and productivity in autosomal dominant polycystic kidney disease (ADPKD), this research was conducted to characterize the burden of illness in patients with ADPKD and assess whether patient-reported outcome (PRO) assessment scores predict clinical and health-economic outcomes. Study Design: Data were analyzed from a prospective, observational study. Setting & Participants: The study cohort comprised 3,409 individuals with ADPKD in 20 countries who were aged 12-78 years and were in chronic kidney disease (CKD) stages G1-G5 and Mayo risk subclasses 1A-1E. Predictors: Scores on PRO instruments, including disease-specific assessments [ADPKD-Impact Scale (ADPKD-IS), and ADPKD-Urinary Impact Scale (ADPKD-UIS)] and generic measures were assessed. Outcomes: Clinical variables [eg, height-adjusted total kidney volume (htTKV), estimated glomerular filtration rate (eGFR), and abdominal girth] and health-economic outcomes were assessed. Analytical Approach: Associations among variables were evaluated using Spearman correlations, logistic regression, and generalized linear mixed effects repeated measures models. Results: Baseline CKD stage and Mayo risk classification showed little correlation with baseline PRO scores; however, scores on disease-specific instruments and measures of physical functioning were worse at more severe CKD stages. PRO scores predicted hospitalizations and sick days at 6-18 months, with strongest associations noted for the ADPKD-IS. PRO scores were not associated with htTKV and eGFR, but worse PRO scores were associated with greater abdominal girth. Poor baseline ADPKD-IS scores were positively associated with occurrence of ADPKD-related symptoms up to 18 months, including kidney pain (OR, 5.30; 95% CI, 2.75-10.24), hematuria (OR, 4.58; 95% CI, 1.99-10.53), and urinary tract infection (OR, 4.41; 95% CI, 1.93-10.11; P < 0.001 for all). Limitations: A limitation of the study was the maximum 18 months of follow-up available to assess outcomes. Conclusions: PRO scores predicted clinical and health-economic outcomes, such as hospitalization and absence from work, underscoring the importance of quality of life assessment of individuals with ADPKD. Plain-Language Summary: Patient-reported outcomes (PROs) are increasingly recognized as important parameters for assessing the clinical and humanistic burden of autosomal dominant polycystic kidney disease (ADPKD). We analyzed data from the observational OVERTURE study to better characterize disease impact on quality of life and determine whether patient-perceived burden might predict outcomes. Scores on PRO assessment instruments predicted hospitalizations and sick days at 6-18 months, with associations strongest for the disease-specific ADPKD-Impact Scale. Compared to patients who rated their health-related quality of life as good, those with poor baseline scores were significantly more likely to report ADPKD-related signs and symptoms up to 18 months of follow-up. These findings support using disease-specific PRO assessment instruments to assess and predict the impact of ADPKD.

18.
Artículo en Inglés | MEDLINE | ID: mdl-38278191

RESUMEN

BACKGROUND: Evidence on ustekinumab safety in pregnancy is gradually expanding, but its clearance in the postnatal period is unknown. The aim of this study was to investigate ustekinumab concentrations in umbilical cord blood and rates of clearance after birth, as well as how these correlate with maternal drug concentrations, risk of infection, and developmental milestones during the first year of life. METHODS: Pregnant women with inflammatory bowel disease were prospectively recruited from 19 hospitals in Denmark and the Netherlands between 2018 and 2022. Infant infections leading to hospitalization/antibiotics and developmental milestones were assessed. Serum ustekinumab concentrations were measured at delivery and specific time points. Nonlinear regression analysis was applied to estimate clearance. RESULTS: In 78 live-born infants from 76 pregnancies, we observed a low risk of adverse pregnancy outcomes and normal developmental milestones. At birth, the median infant-mother ustekinumab ratio was 2.18 (95% confidence interval, 1.69-2.81). Mean time to infant clearance was 6.7 months (95% confidence interval, 6.1-7.3 months). One in 4 infants at 6 months had an extremely low median concentration of 0.015 µg/mL (range 0.005-0.12 µg/mL). No variation in median ustekinumab concentration was noted between infants with (2.8 [range 0.4-6.9] µg/mL) and without (3.1 [range 0.7-11.0] µg/mL) infections during the first year of life (P = .41). CONCLUSIONS: No adverse signals after intrauterine exposure to ustekinumab were observed with respect to pregnancy outcome, infections, or developmental milestones during the first year of life. Infant ustekinumab concentration was not associated with risk of infections. With the ustekinumab clearance profile, live attenuated vaccination from 6 months of age seems of low risk.

19.
Nat Mater ; 23(1): 101-107, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37884670

RESUMEN

Ammonia (NH3) is a key commodity chemical for the agricultural, textile and pharmaceutical industries, but its production via the Haber-Bosch process is carbon-intensive and centralized. Alternatively, an electrochemical method could enable decentralized, ambient NH3 production that can be paired with renewable energy. The first verified electrochemical method for NH3 synthesis was a process mediated by lithium (Li) in organic electrolytes. So far, however, elements other than Li remain unexplored in this process for potential benefits in efficiency, reaction rates, device design, abundance and stability. In our demonstration of a Li-free system, we found that calcium can mediate the reduction of nitrogen for NH3 synthesis. We verified the calcium-mediated process using a rigorous protocol and achieved an NH3 Faradaic efficiency of 40 ± 2% using calcium tetrakis(hexafluoroisopropyloxy)borate (Ca[B(hfip)4]2) as the electrolyte. Our results offer the possibility of using abundant materials for the electrochemical production of NH3, a critical chemical precursor and promising energy vector.

20.
Qual Life Res ; 33(4): 963-973, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38151593

RESUMEN

PURPOSE: The minimal important change (MIC) is defined as the smallest within-individual change in a patient-reported outcome measure (PROM) that patients on average perceive as important. We describe a method to estimate this value based on longitudinal confirmatory factor analysis (LCFA). The method is evaluated and compared with a recently published method based on longitudinal item response theory (LIRT) in simulated and real data. We also examined the effect of sample size on bias and precision of the estimate. METHODS: We simulated 108 samples with various characteristics in which the true MIC was simulated as the mean of individual MICs, and estimated MICs based on LCFA and LIRT. Additionally, both MICs were estimated in existing PROMIS Pain Behavior data from 909 patients. In another set of 3888 simulated samples with sample sizes of 125, 250, 500, and 1000, we estimated LCFA-based MICs. RESULTS: The MIC was equally well recovered with the LCFA-method as using the LIRT-method, but the LCFA analyses were more than 50 times faster. In the Pain Behavior data (with higher scores indicating more pain behavior), an LCFA-based MIC for improvement was estimated to be 2.85 points (on a simple sum scale ranging 14-42), whereas the LIRT-based MIC was estimated to be 2.60. The sample size simulations showed that smaller sample sizes decreased the precision of the LCFA-based MIC and increased the risk of model non-convergence. CONCLUSION: The MIC can accurately be estimated using LCFA, but sample sizes need to be preferably greater than 125.


Asunto(s)
Medición de Resultados Informados por el Paciente , Calidad de Vida , Humanos , Calidad de Vida/psicología , Dolor
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