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1.
Br J Nutr ; : 1-25, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38831516

RESUMEN

Children hospitalised with severe malnutrition have high mortality and readmission rates post-discharge. Current milk-based formulations target restoring ponderal growth but not modification of gut barrier integrety or microbiome which increase risk of gram-negative sepsis and poor outcomes. We propose that legume-based feeds rich in fermentable carbohydrates will promote better gut health and improve overall outcomes.We conducted an open-label Phase II trial at Mbale and Soroti Regional Referral Hospitals, Uganda involving 160 children aged 6 months-5 years with severe malnutrition (mid-upper arm circumference (MUAC) <11.5cm and/or nutritional oedema). Children were randomised to a lactose-free, chickpea-enriched legume paste feed (LF) (n=80) versus WHO standard F75/F100 feeds (n=80). Co-primary outcomes were change in MUAC and mortality to Day 90. Secondary outcomes included weight gain (>5 g/kg/day), de novo development of diarrhoea, time to diarrhoea and oedema resolution.Day 90 MUAC increase was marginally lower in LF versus WHO arm (1.1 cm (IQR 1.1) vs 1.4cm (IQR 1.40) p=0.09; Day 90 mortality was similar 11/80 (13.8%) vs 12/80 (15%) respectively OR 0.91 (95% CI 0.40 -2.07) p=0.83. There were no differences in any of the other secondary outcomes. Owing to initial poor palatability of the legume feed 10 children switched to WHO feeds. Per protocol analysis indicated a trend to lower Day 90 mortality and readmission rates in the legume feed (6/60: (10%) and (2/60: 3%) vs WHO feeds (12/71: 17.5%) and (4/71: 6%) respectively.Further refinement of legume feeds and clinical trials are warrented given the poor outcomes in children with severe malnutrition.Trial registration ISRCTN 10309022.

2.
J Mol Model ; 30(6): 176, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773049

RESUMEN

CONTEXT: In the present work, the influence of aromatic ring substitution on a series of small-donor organic molecules (A, B, C, D, and E) with isoxazole cores was investigated for photovoltaic applications in organic solar cells. Frontier molecular orbital analysis, chemical reactivity descriptors, dipole moment, and population analysis showed that all the organic materials have intramolecular charge transfer abilities capable of donating electrons to the acceptor material (PCBM). The required photovoltaic parameters such as Voc, FF, Jsc, LHE, and other associated optoelectronic parameters are reported. The results demonstrate that aromatic ring substitution influences charge transfer and power conversion efficiencies of solar cells. That is, an increase in the aromatic character of a material increases its charge transfer, and as a result, its photovoltaic properties are increased. Additionally, all the investigated derivatives are good charge transporters with suitable electron reorganization energies, which are beneficial for minimizing energy loss. Hence, these organic derivatives with isoxazole backbones are promising materials and may provide fresh insights into the design of new materials for organic solar cell applications. METHOD: All calculations were performed using DFT and the ORCA 4.1.0 program package as the main tool for geometry optimization and frequency calculations. The Avogadro 1.2.1 visualization tool was used to prepare all input files executed by ORCA 4.1.0. The BP86, B3LYP, and wB97M series of functionals coupled with the def2/TZVP basis set were employed for geometry optimization. All energy-related calculations were carried out using the M06-2x functional. Multiwfn version 3.7 was used for aromaticity and population analysis. Excited state and UV-visible spectra were simulated using the TD-DFT method at the CAM-B3LYP-D3, wB97X-D3, and PBE0-D3 coupled with the ma-def2-TZVP basis set. Moreover, solvent effects were incorporated using the SMD scheme as incorporated in the ORCA software. Lastly, the RIJCOSX approximations were used to speed up calculations while maintaining accuracy.

3.
Chem Biol Drug Des ; 94(4): 1849-1858, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31361393

RESUMEN

A series of 3',4'-dihydro-1'H-spiro(indoline-3,2'-quinolin)-2-ones were prepared by the inverse-electron-demand aza-Diels-Alder reaction (Povarov reaction) of imines derived from isatin and substituted anilines, and the electron-rich alkenes trans-isoeugenol and 3,4-dihydro-2H-pyran. These compounds were assessed for in vitro antiplasmodial activity against drug-sensitive and drug-resistant forms of the P. falciparum parasite. Three compounds derived from 3,4-dihydro-2H-pyran and four compounds derived from trans-isoeugenol showed antiplasmodial activity in the low micromolar range against the drug-resistant FCR-3 strain (1.52-4.20 µM). Only compounds derived from trans-isoeugenol showed antiplasmodial activity against the drug-sensitive 3D7 strain (1.31-1.80 µM).


Asunto(s)
Antimaláricos , Plasmodium falciparum/crecimiento & desarrollo , Antimaláricos/síntesis química , Antimaláricos/química , Antimaláricos/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Compuestos de Espiro/síntesis química , Compuestos de Espiro/química , Compuestos de Espiro/farmacología
4.
Wellcome Open Res ; 3: 95, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30345381

RESUMEN

Background: Changes in intestinal mucosal integrity and gut microbial balance occur in severe acute malnutrition (SAM), resulting in treatment failure and adverse clinical outcomes (gram-negative sepsis, diarrhoea and high case-fatality). Transient lactose intolerance, due to loss of intestinal brush border lactase, also complicates SAM, thus milk based feeds may not be optimal for nutritional rehabilitation. Since the gut epithelial barrier can be supported by short chain fatty acids, derived from microbiota fermentation by particular fermentable carbohydrates, we postulated that an energy-dense nutritional feed comprising of legume-based fermentable carbohydrates, incorporated with lactose-free versions of standard World Health Organization (WHO) F75/F100 nutritional feeds will enhance epithelial barrier function in malnourished children, reduce and promote resolution of diarrhoea and improve overall outcome. Methods: We will investigate in an open-label trial in 160 Ugandan children with SAM, defined by mid-upper arm circumference <11.5cm and/or presence of kwashiorkor. Children will be randomised to a lactose-free, chickpea-enriched feed containing 2 kcal/ml, provided in quantities to match usual energy provision (experimental) or WHO standard treatment F75 (0.75 kcal/ml) and F100 (1 kcal/ml) feeds on a 1:1 basis, conducted at Mbale Regional Referral Hospital nutritional rehabilitation unit. The primary outcomes are change in MUAC at day 90 and survival to day 90. Secondary outcomes include: i) moderate to good weight gain (>5 g/kg/day), ii) de novo development of diarrhoea (>3 loose stools/day), iii) time to diarrhoea resolution (if >3 loose stools/day), and iv) time to oedema resolution (if kwashiorkor) and change in intestinal biomarkers (faecal calprotectin). Discussion: We hypothesize that, if introduced early in the management of malnutrition, such lactose-free, fermentable carbohydrate-based feeds, could safely and cheaply improve global outcome by reducing lactose intolerance-related diarrhoea, improving mucosal integrity and enhancing immunity, and limiting the risk of systemic infection and associated broad-spectrum antibiotic resistance. Registration: ISRCTN 10309022.

5.
Nature ; 552(7685): 386-390, 2017 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-29160306

RESUMEN

The Great Pyramid, or Khufu's Pyramid, was built on the Giza plateau in Egypt during the fourth dynasty by the pharaoh Khufu (Cheops), who reigned from 2509 bc to 2483 bc. Despite being one of the oldest and largest monuments on Earth, there is no consensus about how it was built. To understand its internal structure better, we imaged the pyramid using muons, which are by-products of cosmic rays that are only partially absorbed by stone. The resulting cosmic-ray muon radiography allows us to visualize the known and any unknown voids in the pyramid in a non-invasive way. Here we report the discovery of a large void (with a cross-section similar to that of the Grand Gallery and a minimum length of 30 metres) situated above the Grand Gallery. This constitutes the first major inner structure found in the Great Pyramid since the nineteenth century. The void, named ScanPyramids' Big Void, was first observed with nuclear emulsion films installed in the Queen's chamber, then confirmed with scintillator hodoscopes set up in the same chamber and finally re-confirmed with gas detectors outside the pyramid. This large void has therefore been detected with high confidence by three different muon detection technologies and three independent analyses. These results constitute a breakthrough for the understanding of the internal structure of Khufu's Pyramid. Although there is currently no information about the intended purpose of this void, these findings show how modern particle physics can shed new light on the world's archaeological heritage.

6.
J Health Psychol ; 22(9): 1187-1191, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28805522

RESUMEN

The PACE trial set out to discover whether cognitive behaviour therapy and graded exercise therapy are safe and effective forms of treatment for myalgic encephalomyelitis/chronic fatigue syndrome. It concluded that these interventions could even result in recovery. However, patient evidence has repeatedly found that cognitive behaviour therapy is ineffective and graded exercise therapy can make the condition worse. The PACE trial methodology has been heavily criticised by clinicians, academics and patients. A re-analysis of the data has cast serious doubts on the recovery rates being claimed. The trust of patients has been lost. The medical profession must start listening to people with myalgic encephalomyelitis/chronic fatigue syndrome if trust is going to be restored.


Asunto(s)
Disentimientos y Disputas , Síndrome de Fatiga Crónica/terapia , Ensayos Clínicos Controlados Aleatorios como Asunto , Terapia Cognitivo-Conductual/métodos , Terapia por Ejercicio , Síndrome de Fatiga Crónica/psicología , Humanos , Resultado del Tratamiento
7.
Am J Cardiol ; 109(6): 861-5, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22196785

RESUMEN

Cardiovascular magnetic resonance (CMR) imaging can predict hemodynamically significant coarctation of the aorta (CoA) with a high degree of discrimination. However, the ability of CMR to predict important clinical outcomes in this patient population is unknown. Therefore, we sought to define the ability of CMR to predict the need for surgical or transcatheter intervention in patients with CoA. We retrospectively reviewed the data from 133 consecutive patients who had undergone CMR for the evaluation of known or suspected CoA. The characteristics of the CMR-derived variables predicting the need for surgical or transcatheter intervention for CoA within 1 year were determined through logistic regression analysis. Therapeutic aortic intervention was performed in 41 (31%) of the 133 patients during the study period. The indexed minimum aortic cross-sectional area was the strongest predictor of subsequent intervention (area under the receiver operating characteristic curve 0.975) followed by heart rate-corrected deceleration time in the descending aorta (area under the receiver operating characteristic curve 0.951), and the percentage of flow increase (area under the receiver operating characteristic curve 0.867). The combination of the indexed minimum aortic cross-sectional area and rate-corrected deceleration time in the descending aorta provided the best predictive model (area under the receiver operating characteristic curve 0.986). In conclusion, CMR findings can predict the need for subsequent intervention in CoA. These findings reinforce the "gate-keeper role" of CMR to cardiac catheterization by providing valuable diagnostic and powerful prognostic information and could guide additional treatment of patients with CoA with the final intent of reducing the number of diagnostic catheterizations in such patients.


Asunto(s)
Coartación Aórtica/diagnóstico , Imagen por Resonancia Cinemagnética/estadística & datos numéricos , Adolescente , Adulto , Coartación Aórtica/fisiopatología , Coartación Aórtica/cirugía , Velocidad del Flujo Sanguíneo , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Adulto Joven
8.
Am J Cardiol ; 108(9): 1335-40, 2011 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-21861960

RESUMEN

A published formula containing minimal aortic cross-sectional area and the flow deceleration pattern in the descending aorta obtained by cardiovascular magnetic resonance predicts significant coarctation of the aorta (CoA). However, the existing formula is complicated to use in clinical practice and has not been externally validated. Consequently, its clinical utility has been limited. The aim of this study was to derive a simple and clinically practical algorithm to predict severe CoA from data obtained by cardiovascular magnetic resonance. Seventy-nine consecutive patients who underwent cardiovascular magnetic resonance and cardiac catheterization for the evaluation of native or recurrent CoA at Children's Hospital Boston (n = 30) and the University of California, San Francisco (n = 49), were retrospectively reviewed. The published formula derived from data obtained at Children's Hospital Boston was first validated from data obtained at the University of California, San Francisco. Next, pooled data from the 2 institutions were analyzed, and a refined model was created using logistic regression methods. Finally, recursive partitioning was used to develop a clinically practical prediction tree to predict transcatheter systolic pressure gradient ≥ 20 mm Hg. Severe CoA was present in 48 patients (61%). Indexed minimal aortic cross-sectional area and heart rate-corrected flow deceleration time in the descending aorta were independent predictors of CoA gradient ≥ 20 mm Hg (p <0.01 for both). A prediction tree combining these variables reached a sensitivity and specificity of 90% and 76%, respectively. In conclusion, the presented prediction tree on the basis of cutoff values is easy to use and may help guide the management of patients investigated for CoA.


Asunto(s)
Aorta Torácica/patología , Coartación Aórtica/patología , Imagen por Resonancia Cinemagnética , Índice de Severidad de la Enfermedad , Adolescente , Adulto , Algoritmos , Velocidad del Flujo Sanguíneo , Cateterismo Cardíaco , Niño , Preescolar , Circulación Colateral , Medios de Contraste , Estudios Transversales , Frecuencia Cardíaca , Humanos , Imagenología Tridimensional , Lactante , Modelos Logísticos , Persona de Mediana Edad , Flujo Sanguíneo Regional , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
9.
J Agric Food Chem ; 53(11): 4417-25, 2005 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-15913304

RESUMEN

This study is the first of two publications that investigate the phenomena of coffee nonvolatiles interacting with coffee volatile compounds. The purpose was to identify which coffee nonvolatile(s) are responsible for the interactions observed between nonvolatile coffee brew constituents and thiols, sulfides, pyrroles, and diketones. The overall interaction of these compounds with coffee brews prepared with green coffee beans roasted at three different roasting levels (light, medium, and dark), purified nonvolatiles, and medium roasted coffee brew fractions (1% solids after 1 or 24 h) was measured using a headspace solid-phase microextraction technique. The dark roasted coffee brew was slightly more reactive toward the selected compounds than the light roasted coffee brew. Selected pure coffee constituents, such as caffeine, trigonelline, arabinogalactans, chlorogenic acid, and caffeic acid, showed few interactions with the coffee volatiles. Upon fractionation of medium roasted coffee brew by solid-phase extraction, dialysis, size exclusion chromatography, or anion exchange chromatography, characterization of each fraction, evaluation of the interactions with the aromas, and correlation between the chemical composition of the fractions and the magnitude of the interactions, the following general conclusions were drawn. (1) Low molecular weight and positively charged melanoidins present significant interactions. (2) Strong correlations were shown between the melanoidin and protein/peptide content, on one hand, and the extent of interactions, on the other hand (R = 0.83-0.98, depending on the volatile compound). (3) Chlorogenic acids and carbohydrates play a secondary role, because only weak correlations with the interactions were found in complex matrixes.


Asunto(s)
Coffea/química , Café/química , Odorantes/análisis , Carbohidratos/análisis , Carbohidratos/química , Ácido Clorogénico/análisis , Ácido Clorogénico/química , Interacciones Farmacológicas , Manipulación de Alimentos/métodos , Calor , Proteínas de Plantas/análisis , Polímeros/análisis , Polímeros/química , Semillas/química , Volatilización
10.
J Agric Food Chem ; 53(11): 4426-33, 2005 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-15913305

RESUMEN

This study is the second of two publications that investigate the interactions between volatile and nonvolatile components in coffee brew. The purpose here was to shed some light into the chemical mechanisms responsible for the decrease of volatile thiols when in contact with coffee nonvolatiles. A mixture of volatile thiols covering a large range of physicochemical properties was monitored over time in the presence of a coffee brew model. The binding potential was estimated by SPME-GC-MS. Additives inhibiting specific reaction pathways were preincubated with the coffee brew 1 h prior to addition of the volatile compounds. Degradation kinetics of the volatile thiols were characterized by their rate constants k(obs). The effect of individual additives was shown by calculating k(rel), the relative rate constant as compared to the reference without additive. The conclusion was that thiols, mainly responsible for the "roasty" and "burnt" notes, disappear via two main chemical mechanisms. The results suggest that nucleophilic addition is the major pathway for thiol degradation. Addition occurs on oxidized species generated in the matrix in the presence of air. This mechanism prevails for aliphatic thiols (e.g., ethanethiol, methanethiol). Benzylic thiols (such as 2-furfurylthiol) can react in parallel via another pathway that is slowed in the absence of oxygen and in the presence of a radical scavenger. This points to a radical mechanism, but further work is needed to support this hypothesis. A direct correlation between thiol hydrophobicity and the magnitude of the interactions was shown as well. Therefore, weak physical interactions or hydrophobic assistance accelerating chemical reactions cannot be excluded at this point of the study.


Asunto(s)
Café/química , Odorantes/análisis , Compuestos de Sulfhidrilo/análisis , Compuestos de Sulfhidrilo/química , Fenómenos Químicos , Química Física , Interacciones Farmacológicas , Radicales Libres/química , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Oxidación-Reducción , Volatilización
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