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1.
J Pediatr Gastroenterol Nutr ; 78(6): 1310-1316, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38477385

RESUMEN

OBJECTIVES: This study aimed to evaluate the contributions of the Adapted Celiac Dietary Adherence Test (CDAT) and the Rapid Urinary Gluten Detection Test (u-GIP) in assessing gluten-free diet adherence in children and adolescents with celiac disease. METHODS: Fifty-four celiac patients from two pediatric gastroenterology outpatient clinics affiliated with university hospitals were evaluated. The original CDAT was adapted for children through a transcultural process, and the original cutoff point was adopted to define adherence. A single examiner carried out the u-GIP test in fresh urine samples. Sociodemographic and clinical factors and family food security status were also evaluated. RESULTS: A total of 88.9% of participants (confidence interval [CI]: 77.4-95.8; p<0.001) adhered to the gluten-free diet, as determined by the adapted CDAT score, while 87.0% (CI: 75.1-94.6; p<0.001) had negative u-GIP results. Among the 48 children adhering to the CDAT, six exhibited positive u-GIP results in a urine sample. Of the six nonadherent participants, only one had a positive u-GIP result. Notably, none of the children and adolescents with celiac disease who tested positive for u-GIP reported symptoms on the day of testing, and their growth rates remained stable. CONCLUSIONS: Even celiac children and adolescents adhering to the CDAT questionnaire may show a positive u-GIP in a single measurement without accompanying symptoms or growth impairment. The u-GIP could be helpful in complementary tests in specific situations, such as for patients who exhibit compliant behavior but still experience symptoms or maintain persistent positive serology.


Asunto(s)
Enfermedad Celíaca , Dieta Sin Gluten , Glútenes , Cooperación del Paciente , Humanos , Enfermedad Celíaca/dietoterapia , Enfermedad Celíaca/orina , Enfermedad Celíaca/diagnóstico , Niño , Masculino , Femenino , Adolescente , Cooperación del Paciente/estadística & datos numéricos , Encuestas y Cuestionarios , Glútenes/orina , Preescolar
2.
Molecules ; 26(23)2021 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-34885785

RESUMEN

Heterogeneous catalysis, which has served well the petrochemical industry, may valuably contribute towards a bio-based economy by sustainably enabling selective reactions to renewable chemicals. Carbohydrate-containing matter may be obtained from various widespread sources and selectively converted to furanic platform chemicals: furfural (Fur) and 5-(hydroxymethyl)furfural (Hmf). Valuable bioproducts may be obtained from these aldehydes via catalytic transfer hydrogenation (CTH) using alcohols as H-donors under relatively moderate reaction conditions. Hafnium-containing TUD-1 type catalysts were the first of ordered mesoporous silicates explored for the conversion of Fur and Hmf via CTH/alcohol strategies. The materials promoted CTH and acid reactions leading to the furanic ethers. The bioproducts spectrum was broader for the reaction of Fur than of Hmf. A Fur reaction mechanism based on literature data was discussed and supported by kinetic modelling. The influence of the Hf loading and reaction conditions (catalyst load, type of alcohol H-donor, temperature, initial substrate concentration) on the reaction kinetics was studied. The reaction conditions were optimized to maximize the yields of 2-(alkoxymethyl)furan ethers formed from Fur; up to 63% yield was reached at 88% Fur conversion, 4 h/150 °C, using Hf-TUD-1(75), which was a stable catalyst. The Hf-TUD-1(x) catalysts promoted the selective conversion of Hmf to bis(2-alkoxymethyl)furan; e.g., 96% selectivity at 98% Hmf conversion, 3 h/170 °C for Hf-TUD-1(50).

3.
Emerg Infect Dis ; 23(8): 1253-1259, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28604336

RESUMEN

We summarize the characteristics of dysphagia in 9 infants in Brazil with microcephaly caused by congenital Zika virus infection. The Schedule for Oral Motor Assessment, fiberoptic endoscopic evaluation of swallowing, and the videofluoroscopic swallowing study were used as noninstrumental and instrumental assessments. All infants had a degree of neurologic damage and showed abnormalities in the oral phase. Of the 9 infants, 8 lacked oral and upper respiratory tract sensitivity, leading to delays in initiation of the pharyngeal phase of swallowing. Those delays, combined with marked oral dysfunction, increased the risk for aspiration of food, particularly liquid foods. Dysphagia resulting from congenital Zika virus syndrome microcephaly can develop in infants >3 months of age and is severe.


Asunto(s)
Trastornos de Deglución/etiología , Microcefalia/complicaciones , Microcefalia/virología , Complicaciones Infecciosas del Embarazo/virología , Infección por el Virus Zika/complicaciones , Brasil/epidemiología , Trastornos de Deglución/patología , Femenino , Humanos , Lactante , Microcefalia/epidemiología , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Infección por el Virus Zika/epidemiología
4.
Inorg Chem ; 56(3): 1193-1208, 2017 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-28125229

RESUMEN

Phosphonate- and yttrium-based metal-organic frameworks (MOFs), formulated as [Y(H5btp)]·5.5H2O (1), [Y(H5btp)]·2.5H2O (2), (H3O)[Y2(H5btp)(H4btp)]·H2O (3), and [Y(H5btp)]·H2O·0.5(MeOH) (4), were prepared using a "green" microwave-assisted synthesis methodology which promoted the self-assembly of the tetraphosphonic organic linker [1,1'-biphenyl]-3,3',5,5'-tetrayltetrakis(phosphonic acid) (H8btp) with Y3+ cations. This new family of functional materials, isolated in bulk quantities, exhibits a remarkable breathing effect. Structural flexibility was thoroughly studied by means of X-ray crystallography, thermogravimetry, variable-temperature X-ray diffraction, and dehydration and rehydration processes, ultimately evidencing a remarkable reversible single-crystal to single-crystal (SC-SC) transformation solely through the loss and gain of crystallization solvent molecules. Topologically, frameworks remained unaltered throughout this interconversion mechanism, with all compounds being binodal 6,6-connected network with a Schäfli symbol of {413.62}{48.66.8}. Results show that this is one of the most stable and thermally robust families of tetraphosphonate-based MOFs synthesized reported to date. Porous materials 2 and 3 were further studied to ascertain their performance as heterogeneous catalysts and proton conductors, respectively, with outstanding results being registered for both materials. Compound 2 showed a 94% conversion of benzaldehyde into (dimethoxymethyl)benzene after just 1 h of reaction, among the best results registered to date for MOF materials. On the other hand, the protonic conductivity of compound 3 at 98% of relative humidity (2.58 × 10-2 S cm-1) was among the highest registered among MOFs, with the great advantage of the material to be prepared using a simpler and sustainable synthesis methodology, as well as exhibiting a good stability at ambient conditions (temperature and humidity) over time when compared to others.

6.
Chemistry ; 22(37): 13136-46, 2016 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-27505712

RESUMEN

A positively charged lamellar coordination polymer based on a flexible triphosphonic acid linker is reported. [Gd(H4 nmp)(H2 O)2 ]Cl⋅2 H2 O (1) [H6 nmp=nitrilotris(methylenephosphonic acid)] was obtained by a one-pot approach by using water as a green solvent and by forcing the inclusion of additional acid sites by employing HCl in the synthesis. Compound 1 acts as a versatile heterogeneous acid catalyst with outstanding activity in organic reactions such as alcoholysis of styrene oxide, acetalization of benzaldehyde and cyclohexanaldehyde and ketalization of cyclohexanone. For all reaction systems, very high conversions were reached (92-97 %) in only 15-30 min under mild conditions (35 °C, atmospheric pressure). The coordination polymer exhibits a protonic conductivity of 1.23×10(-5)  S cm(-1) at 98 % relative humidity and 40 °C.

7.
Org Biomol Chem ; 14(16): 3873-7, 2016 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-27035403

RESUMEN

Metal-free cucurbit[7]uril (CB7) solid-state assemblies promote acid-catalysed alcoholysis of aliphatic and aromatic epoxides under mild conditions to give ß-alkoxy alcohols, which are important intermediates for the synthesis of a vast range of compounds such as bioactive pharmaceuticals. The catalytic process is heterogeneous and the catalyst can be reused in consecutive runs without any reactivation treatment. The acid species responsible for the catalytic activity of CB7 may be entrapped hydronium ions.

8.
Inorg Chem ; 54(20): 9690-703, 2015 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-26134888

RESUMEN

The tungsten oxide/2,2'-bipyridine hybrid material [WO3(2,2'-bpy)]·nH2O (n = 1-2) (1) has been prepared in near quantitative yield by the reaction of H2WO4, 2,2'-bpy, and H2O in the mole ratio of ca. 1:2:700 at 160 °C for 98 h in a rotating Teflon-lined digestion bomb. The solid-state structure of 1 was solved and refined through Rietveld analysis of high-resolution synchrotron X-ray diffraction data collected for the microcrystalline powder. The material, crystallizing in the orthorhombic space group Iba2, is composed of a one-dimensional organic-inorganic hybrid polymer, ∞(1)[WO3(2,2'-bpy)], topologically identical to that found in the previously reported anhydrous phases [MO3(2,2'-bpy)] (M = Mo, W). While in the latter the N,N'-chelated 2,2'-bpy ligands of adjacent corner-shared {MO4N2} octahedra are positioned on the same side of the 1D chain, in 1 the 2,2'-bpy ligands alternate above and below the chain. The catalytic behavior of compound 1 for the epoxidation of cis-cyclooctene was compared with that for several other tungsten- or molybdenum-based (pre)catalysts, including the hybrid polymer [MoO3(2,2'-bpy)]. While the latter exhibits superior performance when tert-butyl hydroperoxide (TBHP) is used as the oxidant, compound 1 is superior when aqueous hydrogen peroxide is used, allowing near-quantitative conversion of the olefin to the epoxide. With H2O2, compounds 1 and [MoO3(2,2'-bpy)] act as sources of soluble active species, namely, the oxodiperoxo complex [MO(O2)2(2,2'-bpy)], which is formed in situ. Compounds 1 and [WO(O2)2(2,2'-bpy)] (2) were further tested in the epoxidation of cyclododecene, trans-2-octene, 1-octene, (R)-limonene, and styrene. The structure of 2 was determined by single-crystal X-ray diffraction and found to be isotypical with the molybdenum analogue.

9.
J Pediatr Gastroenterol Nutr ; 61(4): 445-50, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25944218

RESUMEN

OBJECTIVE: The aim of the present study was to investigate the influence of enteral feeding management on occurrences of necrotizing enterocolitis (NEC) in very-low-birth-weight (VLBW) infants. METHODS: This was a case-control study conducted in a sample of 1028 VLBW infants (750 to 1499 g) admitted to a neonatal intensive care unit between January 2003 and May 2008. "Cases" were infants born with VLBW and diagnosed with NEC within the first 30 days of life, and "controls" were VLBW infants who did not develop NEC during this period. Occurrences of NEC were defined using the modified Bell criteria (stage ≥2). RESULTS: Among the 1028 VLBW infants, 55 (5.4%) developed NEC within the first month of life. Logistic regression analysis showed that breast milk given exclusively for <7 days (odds ratio [OR] = 4.02), never achieving full enteral feeding during the first month (OR = 3.50), and parenteral nutrition (OR = 2.70) were factors that increased the chances of NEC occurrence. The use of vasoactive drugs was associated with a lower risk of NEC (OR = 0.15). CONCLUSIONS: Breast milk should be recommended as a priority for the enteral nutrition of VLBW infants for no <7 days. Enteral nutrition should start early and progress quickly to achieve full enteral feeding; these procedures may help reduce the occurrence of NEC.


Asunto(s)
Ingestión de Energía , Nutrición Enteral , Enterocolitis Necrotizante/prevención & control , Retardo del Crecimiento Fetal/fisiopatología , Fenómenos Fisiológicos Nutricionales del Lactante , Leche Humana , Nacimiento Prematuro/fisiopatología , Brasil/epidemiología , Estudios de Casos y Controles , Nutrición Enteral/efectos adversos , Enterocolitis Necrotizante/epidemiología , Enterocolitis Necrotizante/etiología , Femenino , Humanos , Incidencia , Recién Nacido , Recién Nacido de muy Bajo Peso , Unidades de Cuidado Intensivo Neonatal , Modelos Logísticos , Masculino , Nutrición Parenteral/efectos adversos , Embarazo , Riesgo , Vasoconstrictores/efectos adversos , Vasoconstrictores/uso terapéutico , Vasodilatadores/efectos adversos , Vasodilatadores/uso terapéutico
10.
Nanomaterials (Basel) ; 13(23)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38063742

RESUMEN

The integration of metal oxide nanomaterials with mesoporous silica is a promising approach to exploiting the advantages of both types of materials. Traditional synthesis methods typically require multiple steps. This work instead presents a fast, one-step, template-free method for the synthesis of metal oxides homogeneously dispersed within mesoporous silica, including oxides of W, Ti, Nb, Ta, Sn, and Mo. These composites have tunable metal oxide contents, large surface areas, and wide mesopores. The combination of Nb2O5 nanoparticles (NPs) with SiO2 results in an increased surface area and a larger number of acid sites compared to pure Nb2O5 NPs. The surface texture and acidity of the silica-niobia composites can be tuned by adjusting the Nb/Si molar ratio. Moreover, the silica provides protection to the niobia NPs, preventing sintering during thermal treatment at 400 °C. The silica-niobia materials exhibit superior performance as catalysts in the aldol condensation of furfural (Fur) with acetone compared to pure niobia, leading to an up to 62% in product yield. Additionally, these catalysts show remarkable stability, retaining their performance over multiple runs. This work demonstrates the potential of the proposed synthesis approach for preparing more sustainable, high-performance, durable, and stable nanoscale metal oxide-based catalysts with a tunable composition, surface area, and active site density.

11.
Molecules ; 17(4): 3690-707, 2012 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-22450680

RESUMEN

Micro/mesoporous chromium, aluminium-containing silicates of the type TUD-1 (Al-TUD-1, Cr-TUD-1, CrAl-TUD-1) and zeolite BEA, Cr-BEA, and related composites BEA/TUD-1 and Cr-BEA/TUD-1, were prepared, characterised, and tested as solid acids coupled with the ionic liquid (IL) 1-butyl-3-methylimidazolium chloride ([bmim]Cl) as solvent, in the transformation of D-glucose into 5-(hydroxymethyl)-2-furaldehyde (Hmf), at 120 °C. The chromium-containing catalytic systems lead to considerably higher Hmf yields in comparison to the related systems without chromium. The IL is a favourable solvent for this target reaction (in terms of Hmf yields reached) compared to water or dimethylsulfoxide. A detailed study on the stabilities of the nanoporous solid acids in the IL medium is presented.


Asunto(s)
Silicatos de Aluminio/química , Cromo/química , Furaldehído/análogos & derivados , Glucosa/química , Líquidos Iónicos/química , Catálisis , Furaldehído/química , Imidazoles/química , Solventes/química
12.
Front Chem ; 10: 1006981, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36247668

RESUMEN

The biomass-derived platform chemicals furfural and 5-(hydroxymethyl)furfural (HMF) may be converted to α-angelica lactone (AnL) and levulinic acid (LA). Presently, LA (synthesized from carbohydrates) has several multinational market players. Attractive biobased oxygenated fuel additives, solvents, etc., may be produced from AnL and LA via acid and reduction chemistry, namely alkyl levulinates and γ-valerolactone (GVL). In this work, hierarchical hafnium-containing multifunctional Linde type L (LTL) related zeotypes were prepared via top-down strategies, for the chemical valorization of LA, AnL and HMF via integrated catalytic transfer hydrogenation (CTH) and acid reactions in alcohol medium. This is the first report of CTH applications (in general) of LTL related materials. The influence of the post-synthesis treatments/conditions (desilication, dealumination, solid-state impregnation of Hf or Zr) on the material properties and catalytic performances was studied. AnL and LA were converted to 2-butyl levulinate (2BL) and GVL in high total yields of up to ca. 100%, at 200°C, and GVL/2BL molar ratios up to 10. HMF conversion gave mainly the furanic ethers 5-(sec-butoxymethyl)furfural and 2,5-bis(sec-butoxymethyl)furan (up to 63% total yield, in 2-butanol at 200°C/24 h). Mechanistic, reaction kinetics and material characterization studies indicated that the catalytic results depend on a complex interplay of different factors (material properties, type of substrate). The recovered-reused solids performed steadily.

13.
Inorg Chem ; 50(2): 525-38, 2011 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-21141938

RESUMEN

The dioxomolybdenum(VI) complexes [MoO2Cl2(PzPy)] (1) and [MoO2(OSiPh3)2(PzPy)] (5) (PzPy = 2-[3(5)-pyrazolyl]pyridine) were synthesized and characterized by vibrational spectroscopy, with assignments being supported by DFT calculations. Complex 5 was additionally characterized by single crystal X-ray diffraction. Recrystallization of 1 under different conditions originated crystal structures containing either the mononuclear [MoO2Cl2(PzPy)] complex co-crystallized with 2-[3(5)-pyrazolyl]pyridinium chloride, binuclear [Mo2O4(µ2-O)Cl2(PzPy)2] complexes, or the oxodiperoxomolybdenum(VI) complex [MoO(O2)2Cl(PzPyH)], in which a 2-[3(5)-pyrazolyl]pyridinium cation weakly interacts with the Mo(VI) center via a pyrazolyl N-atom. The crystal packing in the different structures is mediated by a variety of supramolecular interactions: hydrogen bonding involving the pyridinium and/or pyrazolyl N-H groups, weak CH · · · O and CH · · · π contacts, and strong π-π stacking. Complexes 1 and 5 are moderately active catalysts for the epoxidation of cis-cyclooctene at 55 °C using tert-butylhydroperoxide as oxidant, giving 1,2-epoxycyclooctane as the only reaction product. Insoluble materials were recovered at the end of the first catalytic runs and characterized by IR spectroscopy, elemental analysis, scanning electron microscopy (SEM)-energy dispersive spectroscopy (EDS), and powder X-ray diffraction. For complex 5 the loss of the triphenylsiloxy ligands during the catalytic run resulted in the formation of a tetranuclear complex, [Mo4O8(µ2-O)4(PzPy)4]. The recovered solids could be used as efficient heterogeneous catalysts for the epoxidation of cyclooctene, showing no loss of catalytic performance between successive catalytic runs.

14.
Inorg Chem ; 49(15): 6865-73, 2010 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-20604548

RESUMEN

The reaction of [MoO(2)Cl(2)(bipy)] (1) (bipy = 2,2'-bipyridine) with water in a Teflon-lined stainless steel autoclave (100 degrees C, 19 h), in an open reflux system with oil bath heating (12 h) or in a microwave synthesis system (120 degrees C, 4 h), gave the molybdenum oxide/bipyridine hybrid material {[MoO(3)(bipy)][MoO(3)(H(2)O)]}(n) (2) as a microcrystalline powder in yields of 72-92%. The crystal structure of 2 determined from synchrotron X-ray powder diffraction data is composed of two distinct neutral one-dimensional polymers: an organic-inorganic polymer, [MoO(3)(bipy)](n), and a purely inorganic chain, [MoO(3)(H(2)O)](n), which are interconnected by O-H...O hydrogen bonding interactions. Compound 2 is a moderately active, stable, and selective catalyst for the epoxidation of cis-cyclooctene at 55 degrees C with tert-butylhydroperoxide (tBuOOH, 5.5 M in decane or 70% aqueous) as the oxidant. Biphasic solid-liquid or triphasic solid-organic-aqueous mixtures are formed, and 1,2-epoxycyclooctane is the only reaction product. When n-hexane is employed as a cosolvent and tBuOOH(decane) is the oxidant, the catalytic reaction is heterogeneous in nature, and the solid catalyst can be recycled and reused without a loss of activity. For comparison, the catalytic performance of the precursor 1 was also investigated. The IR spectra of solids recovered after catalysis indicate that 1 transforms into the organic-inorganic polymer [MoO(3)(bipy)] when the oxidant is tBuOOH(decane) and compound 2 when the oxidant is 70% aqueous tBuOOH.


Asunto(s)
2,2'-Dipiridil/química , Ciclooctanos/química , Compuestos Epoxi/química , Molibdeno/química , Compuestos Organometálicos/química , Compuestos Organometálicos/síntesis química , Catálisis , Cristalografía por Rayos X , Calor , Microondas , Modelos Moleculares , Conformación Molecular , Estereoisomerismo
15.
Molecules ; 15(6): 3863-77, 2010 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-20657413

RESUMEN

The one-pot acid-catalysed conversion of mono/di/polysaccharides (inulin, xylan, cellobiose, sucrose, glucose, fructose, xylose) into 2-furfuraldehyde (FUR) or 5-hydroxymethylfurfural (HMF) in the presence of aluminium-containing mesoporous TUD-1 (denoted as Al-TUD-1, Si/Al = 21), at 170 degrees C was investigated. Xylose gave 60% FUR yield after 6 h reaction; hexose-based mono/disaccharides gave less than 20% HMF yield; polysaccharides gave less than 20 wt % FUR or HMF yields after 6 h. For four consecutive 6 h batches of the xylose reaction in the presence of Al-TUD-1, the FUR yields achieved were similar, without significant changes in Si/Al ratio.


Asunto(s)
Ácidos/química , Aldehídos/química , Aldehídos/síntesis química , Furaldehído/química , Furaldehído/síntesis química , Catálisis , Fructosa/química , Furaldehído/análogos & derivados , Modelos Químicos , Polisacáridos/química , Sacarosa/química , Xilosa/química
16.
Dalton Trans ; 48(30): 11508-11519, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31292582

RESUMEN

The reaction of the macrocyclic cavitand cucurbit[6]uril (CB[6]) and the diaqua complex [MoO2Cl2(H2O)2] in hydrochloric acid solution gave a water insoluble supramolecular compound with the general composition 2[MoO2Cl2(H2O)2]·CB[6]·xH2O·yHCl·z(CH3COCH3) (2). Single crystal X-ray diffraction (XRD) analysis revealed the presence of barrel-shape supramolecular entities, {CB[6]·10(H2O)}, aligned in layers which are shifted relative to adjacent layers to form a brick-like pattern. The CB[6]/water hydrogen-bonded entities further engage in intermolecular interactions with water, HCl and [MoO2Cl2(H2O)2] molecules to form a three-dimensional (3D) framework. Compound 2 was characterised by thermogravimetric analysis (TGA), IR and Raman vibrational spectroscopy, and 13C{1H} CP MAS NMR. The reference complex [MoO2Cl2(H2O)2]·(diglyme)2 (1) and compound 2 were studied for the oxidative catalytic conversion of olefins (cis-cyclooctene, cyclohexene and styrene) with aqueous H2O2 as oxidant. Using alcohols as solvents, 2 was employed in a one-pot two-stage strategy for converting olefins to alkoxy products, which involves oxidation (with H2O2) and acid chemistry. Mechanistic studies were carried out using different intermediates as substrates, and the type of solvent and substrate scope were investigated. The results demonstrated the ability of the CB[6]/MoVI supramolecular adduct to function as an acid-oxidation multifunctional catalyst, and its recovery and reuse via relatively simple procedures.

17.
J Pediatr (Rio J) ; 93(6): 632-638, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28628759

RESUMEN

OBJECTIVE: To verify whether infants with cow's milk protein allergy have inadequate vitamin D levels. METHODS: This cross-sectional study included 120 children aged 2 years or younger, one group with cow's milk protein allergy and a control group. The children were recruited at the pediatric gastroenterology, allergology, and pediatric outpatient clinics of a university hospital in the Northeast of Brazil. A questionnaire was administered to the caregiver and blood samples were collected for vitamin D quantification. Vitamin D levels <30ng/mL were considered inadequate. Vitamin D level was expressed as mean and standard deviation, and the frequency of the degrees of sufficiency and other variables, as proportions. RESULTS: Infants with cow's milk protein allergy had lower mean vitamin D levels (30.93 vs.35.29ng/mL; p=0.041) and higher deficiency frequency (20.3% vs.8.2; p=0.049) than the healthy controls. Exclusively or predominantly breastfed infants with cow's milk protein allergy had higher frequency of inadequate vitamin D levels (p=0.002). Regardless of sun exposure time, the groups had similar frequencies of inadequate vitamin D levels (p=0.972). CONCLUSIONS: Lower vitamin D levels were found in infants with CMPA, especially those who were exclusively or predominantly breastfed, making these infants a possible risk group for vitamin D deficiency.


Asunto(s)
Hipersensibilidad a la Leche/sangre , Hipersensibilidad a la Leche/complicaciones , Deficiencia de Vitamina D/etiología , Vitamina D/sangre , Estudios de Casos y Controles , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Masculino , Factores Socioeconómicos , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/diagnóstico
18.
Chem Commun (Camb) ; 51(54): 10807-10, 2015 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-25966779

RESUMEN

Rationalization of the synthetic conditions allowed the predictable fast sustainable preparation of [La2(H3nmp)2(H2O)4]·4.5H2O having a 1D coordination polymer. The material exhibits a remarkable chemical stability, can be converted into other layered compounds, and is an excellent catalyst surpassing other related materials.

19.
Arq Bras Endocrinol Metabol ; 48(6): 823-7, 2004 Dec.
Artículo en Portugués | MEDLINE | ID: mdl-15761555

RESUMEN

To know the prevalence of celiac disease (CD) in a group of children and adolescents with type I diabetes mellitus. A cross sectional study was conducted at the Instituto Materno Infantil de Pernambuco (IMIP) in March 2000. The sample consisted of 19 children and adolescents with type I diabetes mellitus that had the human anti-tissue transglutaminase antibodies assessed using kits from the Eurospital Laboratory. In case of positive results it was realized small intestine biopsy to confirm the diagnosis. For the calculation of the prevalence of CD it was considered the number of patients with serum positive histological alterations of the mucous membrane of the small intestine compatible with CD. Four patients presented serum positivity for human anti-tissue transglutaminase antibodies with a serum prevalence of 21% (4/19). Out of these four subjects, three who accomplished small intestine biopsy presented histological alterations compatible with CD. The prevalence of CD in this group was 15.8% (3/19). The prevalence of CD in this study group was high, suggesting that those with type I diabetes mellitus should be led as a group of high risk to develop this disease.


Asunto(s)
Enfermedad Celíaca/epidemiología , Diabetes Mellitus Tipo 1/complicaciones , Adolescente , Enfermedad Celíaca/etiología , Niño , Estudios Transversales , Complicaciones de la Diabetes/epidemiología , Complicaciones de la Diabetes/etiología , Femenino , Humanos , Prevalencia
20.
ChemSusChem ; 7(3): 804-12, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24497470

RESUMEN

The acid-catalyzed reaction of 5-(hydroxymethyl)-2-furfural with ethanol is a promising route to produce biofuels or fuel additives within the carbohydrate platform; specifically, this reaction may give 5-ethoxymethylfurfural, 5-(ethoxymethyl)furfural diethylacetal, and/or ethyl levulinate (bioEs). It is shown that sulfonated, partially reduced graphene oxide (S-RGO) exhibits a more superior catalytic performance for the production of bioEs than several other acid catalysts, which include sulfonated carbons and the commercial acid resin Amberlyst-15, which has a much higher sulfonic acid content and stronger acidity. This was attributed to the cooperative effects of the sulfonic acid groups and other types of acid sites (e.g., carboxylic acids), and to the enhanced accessibility to the active sites as a result of the 2D structure. Moreover, the acidic functionalities bonded to the S-RGO surface were more stable under the catalytic reaction conditions than those of the other solids tested, which allowed its efficient reuse.


Asunto(s)
Biocombustibles , Furaldehído/análogos & derivados , Grafito/química , Óxidos/química , Ácidos Sulfónicos/química , Catálisis , Furaldehído/química , Ácidos Levulínicos/química , Oxidación-Reducción
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