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1.
Acta Paediatr ; 112(10): 2104-2112, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37332100

RESUMEN

AIM: We examined the correlation between how long it took the parents of very low birthweight infants, born weighing up to 1500 g, to provide different kinds of autonomous care in a neonatal intensive care unit (NICU). METHODS: This prospective observational was conducted in the NICU of a Spanish hospital from 10 January 2020 to 3 May 2022. The unit had 11 beds single-family rooms and provided eight beds in an open bay room. The study examined breastfeeding, patient safety, participation in rounds, pain prevention and cleanliness. RESULTS: We studied 96 patients and their parents and there was no correlation between any type of care and the time it took parents to provide it autonomously. Parents in the single-family room cohort spent a median of 9.5 h per day between them in the NICU, while the parents in the open bay room spent 7.0 h with their infants (p = 0.03). However, parents in the single-family room group were able to recognise pain faster (p = 0.02). CONCLUSION: Parents in single-family rooms spent more time in the NICU and recognised pain faster but did not achieve autonomous care faster than parents in the open bay group.


Asunto(s)
Unidades de Cuidado Intensivo Neonatal , Padres , Recién Nacido , Femenino , Humanos , Lactante , Peso al Nacer , Lactancia Materna , Recién Nacido de muy Bajo Peso
2.
Actual. nutr ; 23(3): 146-156, jul 2022.
Artículo en Español | LILACS | ID: biblio-1418121

RESUMEN

Introducción: el sodio (Na) es un elemento abundante en la naturaleza y presente en el agua y en los alimentos que consumimos. El consumo excesivo de Na que, mayormente, proviene de alimentos procesados, es un factor de riesgo para el desarrollo de hipertensión arterial y de enfermedad cardiovascular. En Argentina, el consumo de Na duplica el consumo máximo recomendado de 2000 mg/día. Objetivo: evaluar el contenido de Na de alimentos del mercado argentino y comparar dichos valores con los declarados en los rótulos nutricionales. Materiales y métodos: se seleccionaron 97 productos de diversas categorías (fiambres, quesos, bebidas analcohólicas, galletitas). La concentración de Na se midió por espectroscopía de emisión y se expresó en mg Na/100 g/mL. Resultados: el contenido declarado de Na para los alimentos analizados fue de 630 [10-1833] (mediana [rango]), mientras que el Na medido fue de 645 [6.9-3278]; para las bebidas analcohólicas el Na declarado fue 14 [0-46] y el Na medido 3.7 [0.8-36]. Se halló diferencia significativa entre los valores de Na declarados y medidos en fiambres y bebidas analcohólicas (test de Wilcoxon, p<0.05). Un 41% del valor medido de Na en los alimentos analizados está dentro de la tolerancia ± 20% que exige el Código Alimentario Argentino y un 92% de las bebidas analcohólicas tienen un valor medido menor a dicho intervalo. Conclusiones: los valores declarados y medidos son diferentes para las categorías de fiambres y bebidas analcohólicas, lo que impediría una correcta estimación de la ingesta de Na a partir de estos alimentos


Introduction: sodium (Na) is an element abundant in nature and present in the water and food. The excessive consumption of Na, which mainly comes from processed foods, is a risk factor for the development of high blood pressure and cardiovascular disease. In Argentina, Na consumption doubles the maximum recommended consumption of 2000 mg/day. Objective: to evaluate the Na content of foods in the Argentine market and to compare the values of these with those declared in the nutritional labels. Materials and Methods: 97 products were selected from various categories (cold cuts, cheeses, sweetened beverages, cookies). The Na concentration was measured by emission spectroscopy and was expressed in mg Na/100 g/mL. Results: The median and range of the declared Na was for the foods analyzed was 630 [10-1833] (median [range]), while the measured Na was 645 [6.9-3278]; for non-alcoholic beverages, declared Na was 14 [0-46] and measured Na was 3.7 [0.8-36]. A significant difference was found between the Na values declared and measured in cold cuts and sweetened beverages (Wilcoxon test, p<0.05). Forty one percent of the measured value of Na in the foods analyzed are within the tolerance ± 20% required by The Argentine Food Code and 92% of the non-alcoholic beverages have a measured value lower than said interval. Conclusions: the declared and measured values are different for the categories of cold cuts and non-alcoholic beverages, which would prevent a correct estimation of the Na intake from these foods


Asunto(s)
Humanos , Composición de Alimentos , Etiquetado de Alimentos , Argentina , Sales (Química) , Bebidas
3.
J Org Chem ; 86(1): 103-109, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33245661

RESUMEN

Aryl boronic acids and esters are important building blocks in API synthesis. The palladium-catalyzed Suzuki-Miyaura borylation is the most common method for their preparation. This paper describes an improvement of the current reaction conditions. By using lipophilic bases such as potassium 2-ethyl hexanoate, the borylation reaction could be achieved at 35 °C in less than 2 h with very low palladium loading (0.5 mol %). A preliminary mechanistic study shows a hitherto unrecognized inhibitory effect by the carboxylate anion on the catalytic cycle, whereas 2-ethyl hexanoate minimizes this inhibitory effect. This improved methodology enables borylation of a wide range of substrates under mild conditions.

4.
Angew Chem Int Ed Engl ; 57(33): 10630-10634, 2018 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-29856904

RESUMEN

Pairing a range of bis(aryl) zinc reagents ZnAr2 with the stronger Lewis acidic [(ZnArF2 )] (ArF =C6 F5 ), enables highly stereoselective cross-coupling between glycosyl bromides and ZnAr2 without the use of a transition metal. Reactions occur at room temperature with excellent levels of stereoselectivity, where ZnArF2 acts as a non-coupling partner although its presence is crucial for the execution of the C(sp2 )-C(sp3 ) bond formation process. Mechanistic studies have uncovered a unique synergistic partnership between the two zinc reagents, which circumvents the need for transition-metal catalysis or forcing reaction conditions. Key to the success of the coupling is the avoidance of solvents that act as Lewis bases versus diarylzinc compounds (e.g. THF).

5.
J Org Chem ; 81(7): 2804-16, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26914598

RESUMEN

The unexpected ability of arylzinc reagents bearing electron-donating substituents to react in a Friedel-Crafts fashion (cine) with electrophiles like perpivaloylated glucoside bromide and benzhydryl bromides in competition with organometallic coupling (ipso) is shown. The stereoelectronic factors required to promote the cine reactivity versus the classical ipso, and the mechanism of this alternative pathway, have been investigated. The Wheland intermediate is deprotonated intramolecularly in a 1,2-shift but also in a longer-range shift, leaving in this case the C-Zn untouched. In the latter case, it is possible to take advantage of this result for further functionalization.

6.
Org Biomol Chem ; 11(15): 2482-92, 2013 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-23440078

RESUMEN

An efficient asymmetric synthesis of cyclo-archaeol and ß-glucosyl cyclo-archaeol is presented employing catalytic asymmetric conjugate addition and catalytic epoxide ring opening as the key steps. Their occurrence in deep sea hydrothermal vents has been confirmed by chromatographic comparison with natural samples.


Asunto(s)
Archaea/química , Glicerofosfolípidos/química , Glicerofosfolípidos/síntesis química , Catálisis , Técnicas de Química Sintética
8.
Org Lett ; 13(3): 402-5, 2011 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-21175140

RESUMEN

Enantioselective nitrone cycloadditions with 2-alkenoyl pyridine N-oxides as dipolarophiles have been reported. The reaction is catalyzed by Cu(II)-BOX complexes to give the expected isoxazolidine products with high diastereo- and enantioselectivity.


Asunto(s)
Alquenos/química , Cobre/química , Isoxazoles/síntesis química , Óxidos de Nitrógeno/química , Compuestos Organometálicos/química , Piridinas/química , Catálisis , Isoxazoles/química , Estructura Molecular , Estereoisomerismo
9.
J Org Chem ; 73(16): 6389-92, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18646826

RESUMEN

Alpha'-arylsulfonyl enones are efficient bidentate dienophiles for the Cu(II)-bis(oxazoline) catalyzed enantioselective Diels-Alder reaction with a number of dienes, affording the corresponding products with good to high enantiomeric excesses. The resulting products can be alkylated and the sulfone removed, so alpha'-arylsulfonyl enones can be regarded as surrogates of simple monodentate enones, which are poor dienophiles with this catalytic system.


Asunto(s)
Cobre/química , Cetonas/química , Oxazoles/química , Sulfonas/química , Catálisis , Compuestos Organometálicos/química , Polienos/química , Estereoisomerismo
10.
Org Lett ; 9(10): 1983-6, 2007 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-17447775

RESUMEN

2-Alkenoyl pyridine N-oxides are introduced as a new kind of efficient dienophiles for the Cu(II)-bis(oxazoline) (BOX) catalyzed enantioselective Diels-Alder reaction affording higher reactivity and enantioselectivity (ee's up to 96%) than the corresponding nonoxidized 2-alkenoyl pyridines.


Asunto(s)
Alquenos/química , Cobre/química , Oxazoles/química , Piridinas/química , Compuestos Aza/química , Catálisis , Chalcona/química , Ciclopentanos/química , Isomerismo , Estructura Molecular , Piridinas/síntesis química
11.
J Org Chem ; 69(20): 6821-9, 2004 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-15387607

RESUMEN

An easy access to substituted (R)-3-hydroxy-3-phenyloxindoles, (R)-benzylic acids, and benzophenones is described. The reaction of the lithium enolate of the (2S,5S)-cis-1,3-dioxolan-4-one derived from optically active (S)-mandelic acid and pivalaldehyde with several o- and p-halonitrobenzenes proceeds readily to give the corresponding arylation products in good yields and diastereoselectivities. The reduction of the nitro group with Zn/HCl/EtOH in the o-nitro arylation products with concomitant intramolecular aminolysis of the dioxolanone moiety leads directly to enantiomerically pure (R)-3-hydroxy-3-phenyloxindoles. On the other hand the basic hydrolysis of the dioxolanone moiety in all the arylation products (ortho and para) leads to enantiomerically pure substituted (R)-benzylic acids. The oxidative decarboxylation of these latter with oxygen as terminal oxidant in the presence of pivalaldehyde and the Co(III)-Me2opba complex as catalyst gives substituted nitrobenzophenones.

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