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1.
Chem Sci ; 14(48): 14140-14145, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38098714

RESUMEN

Coordination cage catalysis has commonly relied on the endogenous binding of substrates, exploiting the cavity microenvironment and spatial constraints to engender increased reactivity or interesting selectivity. Nonetheless, there are issues with this approach, such as the frequent occurrence of product inhibition or the limited applicability to a wide range of substrates and reactions. Here we describe a strategy in which the cage acts as an exogenous catalyst, wherein reactants, intermediates and products remain unbound throughout the course of the catalytic cycle. Instead, the cage is used to alter the properties of a cofactor guest, which then transfers reactivity to the bulk-phase. We have exemplified this approach using photocatalysis, showing that a photoactivated host-guest complex can mediate [4 + 2] cycloadditions and the aza-Henry reaction. Detailed in situ photolysis experiments show that the cage can both act as a photo-initiator and as an on-cycle catalyst where the quantum yield is less than unity.

2.
Chem Soc Rev ; 52(7): 2322-2357, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-36811891

RESUMEN

Typical PeT-based fluorescent probes are multi-component systems where a fluorophore is connected to a recognition/activating group by an unconjugated linker. PeT-based fluorescent probes are powerful tools for cell imaging and disease diagnosis due to their low fluorescence background and significant fluorescence enhancement towards the target. This review provides research progress towards PeT-based fluorescent probes that target cell polarity, pH and biological species (reactive oxygen species, biothiols, biomacromolecules, etc.) over the last five years. In particular, we emphasise the molecular design strategies, mechanisms, and application of these probes. As such, this review aims to provide guidance and to enable researchers to develop new and improved PeT-based fluorescent probes, as well as promoting the use of PeT-based systems for sensing, imaging, and disease therapy.


Asunto(s)
Electrones , Colorantes Fluorescentes , Colorantes Fluorescentes/química , Transporte de Electrón , Diagnóstico por Imagen , Fluorescencia
3.
Inorg Chem ; 62(5): 1827-1832, 2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-35512336

RESUMEN

The host-guest chemistry of coordination cages continues to promote significant interest, not least because confinement effects can be exploited for a range of applications, such as drug delivery, sensing, and catalysis. Often a fundamental analysis of noncovalent encapsulation is required to provide the necessary insight into the design of better functional systems. In this paper, we demonstrate the use of various techniques to probe the host-guest chemistry of a novel Pd2L4 cage, which we show is preorganized to selectively bind dicyanoarene guests with high affinity through hydrogen-bonding and other weak interactions. In addition, we exemplify the use of Raman spectroscopy as a tool for analyzing coordination cages, exploiting alkyne and nitrile reporter functional groups that are contained within the host and guest, respectively.

4.
Mayo Clin Proc ; 97(8): 1437-1448, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35933132

RESUMEN

OBJECTIVE: To compare dietary factors between incident symptomatic stone formers and controls, and among the incident stone formers, to determine whether dietary factors were predictive of symptomatic recurrence. PATIENTS AND METHODS: We prospectively recruited 411 local incident symptomatic kidney stone formers (medical record validated) and 384 controls who were seen at Mayo Clinic in Minnesota or Florida between January 1, 2009, and August 31, 2018. Dietary factors were based on a Viocare, Inc, food frequency questionnaire administered during a baseline in-person study visit. Logistic regression compared dietary risk factors between incident symptomatic stone formers and controls. Incident stone formers were followed up for validated symptomatic recurrence in the medical record. Cox proportional hazards models estimated risk of symptomatic recurrence with dietary factors. Analyses adjusted for fluid intake, energy intake, and nondietary risk factors. RESULTS: In fully adjusted analyses, lower dietary calcium, potassium, caffeine, phytate, and fluid intake were all associated with a higher odds of an incident symptomatic kidney stone. Among incident stone formers, 73 experienced symptomatic recurrence during a median 4.1 years of follow-up. Adjusting for body mass index, fluid intake, and energy intake, lower dietary calcium and lower potassium intake were predictive of symptomatic kidney stone recurrence. With further adjustment for nondietary risk factors, lower dietary calcium intake remained a predictor of recurrence, but lower potassium intake only remained a predictor of recurrence among those not taking thiazide diuretics or calcium supplements. CONCLUSION: Enriching diets in stone formers with foods high in calcium and potassium may help prevent recurrent symptomatic kidney stones.


Asunto(s)
Calcio de la Dieta , Cálculos Renales , Calcio , Dieta/efectos adversos , Humanos , Cálculos Renales/epidemiología , Cálculos Renales/etiología , Potasio , Factores de Riesgo
5.
Molecules ; 26(3)2021 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-33540541

RESUMEN

Three new heterometallic [CrIII8NiII6] coordination cubes of formulae [CrIII8NiII6L24(H2O)12](NO3)12 (1), [CrIII8NiII6L24(MeCN)7(H2O)5](ClO4)12 (2), and [CrIII8NiII6L24Cl12] (3) (where HL = 1-(4-pyridyl)butane-1,3-dione), were synthesised using the paramagnetic metalloligand [CrIIIL3] and the corresponding NiII salt. The magnetic skeleton of each capsule describes a face-centred cube in which the eight CrIII and six NiII ions occupy the eight vertices and six faces of the structure, respectively. Direct current magnetic susceptibility measurements on (1) reveal weak ferromagnetic interactions between the CrIII and NiII ions, with JCr-Ni = + 0.045 cm-1. EPR spectra are consistent with weak exchange, being dominated by the zero-field splitting of the CrIII ions. Excluding wheel-like structures, examples of large heterometallic clusters containing both CrIII and NiII ions are rather rare, and we demonstrate that the use of metalloligands with predictable bonding modes allows for a modular approach to building families of related polymetallic complexes. Compounds (1)-(3) join the previously published, structurally related family of [MIII8MII6] cubes, where MIII = Cr, Fe and MII = Cu, Co, Mn, Pd.


Asunto(s)
Cromo/química , Complejos de Coordinación/química , Níquel/química , Fenómenos Magnéticos , Modelos Moleculares , Conformación Molecular
6.
Chem Commun (Camb) ; 56(79): 11799-11802, 2020 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-33021303

RESUMEN

The self-assembly of Pd4L2 metallocylcic and Pd6L3 trigonal prismatic assemblies are described. The selection of one species over the other has been achieved by careful choice of ancilliary ligands, which switch the dynamics of the Pd-pyridine bonds such that a highly unusual and distorted smaller assembly can be kinetically trapped en route to the more energetically favourable larger species. Both assemblies provide promise as easy to access multicavity reaction vessels.

7.
Dalton Trans ; 48(27): 10180-10190, 2019 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-31187830

RESUMEN

A family of mono- and ditopic hydroxamic acids has been employed in the synthesis and structural and physical characterisation of discrete (0D) and (1- and 2-D) extended network coordination complexes. Examples of the latter include the 1-D coordination polymer {[Zn(ii)(L3H)2]·2MeOH}n (5; L3H2 = 2-(methylamino)phenylhydroxamic acid) and the 2-D extended network {[Cu(ii)(L2H)(H2O)(NO3)]·H2O}n (5; L2H2 = 4-amino-2-(acetoxy)phenylhydroxamic acid). The 12-MC-4 metallacrown [Cu(ii)5(L4H)4(MeOH)2(NO3)2]·3H2O·4MeOH (7) represents the first metal complex constructed using the novel ligand N-hydroxy-2-[(2-hydroxy-3-methoxybenzyl)amino]benzamide (L4H3). Variable temperature magnetic susceptibility studies confirm strong antiferromagnetic exchange between the Cu(ii) centres in 7. Coordination polymer 5 shows photoluminescence in the blue region (λPL∼ 421-450 nm) with a bathochromic shift of the emission (∼15-30 nm) from solution to the solid state.

8.
Dalton Trans ; 48(4): 1477-1488, 2019 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-30632582

RESUMEN

Previous employment of the ligands 2-methoxy-6-[(methylimino)methyl]phenol (L1H) and 2-methoxy-6-[(phenylimino)methyl]phenol (L2H) has resulted in the self-assembly of pseudo metallocalix[6]arene complexes of general formulae: [M7(µ3-OH)6(Lx)6](NO3)y (M = Ni(ii), x = 1, y = 2 (1) and Co(ii/iii), x = 2, y = 3 (2)). Extrapolating upon this work, we report the coordination chemistry of ligands 2-methoxy-6-{[(2-methoxyphenyl)imino]methyl}phenol (L3H), 2-[(benzylimino)methyl]-6-methoxyphenol (L4H), 2-[(benzylamino)methyl]-6-methoxyphenol (L5H) and 2-[(benzylamino)methyl]-4-bromo-6-methoxyphenol (L6H), whose structures are modifications of ligands L1-2H. These ligands are employed in the synthesis and characterisation of the dimetallic complex [Ni(ii)2(L3)3(H2O)](NO3)·2H2O·3MeOH (3); the monometallic complexes [Ni(ii)(L4)2] (4) and [Co(iii)(L4)3]·H2O·MeOH (5a); and the tetranuclear pseudo metallocalix[4]arene complexes: [(NO3)⊂Co(ii)4(µ3-OH)2(L5)4(H2O)2](NO3)·H2O (6), [(NO3)⊂Ni(ii)4(µ3-OH)2(L5)4(H2O)2](NO3)·H2O (7) and [Ni(ii)4(µ3-OH)2(L6)4(NO3)2]·MeCN (8). The tetrametallic 'butterfly' core topologies in 6-8 are discussed with respect to their structural and topological relationship with their heptanuclear [M7] (M = Co(ii), Ni(ii)) pseudo metallocalix[6]arene ancestors (1 and 2).

9.
Inorg Chem ; 57(7): 3500-3506, 2018 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-29323893

RESUMEN

The reaction of the simple metalloligand [FeIIIL3] [HL = 1-(4-pyridyl)butane-1,3-dione] with a variety of different MII salts results in the formation of a family of heterometallic cages of formulae [FeIII8PdII6L24]Cl12 (1), [FeIII8CuII6L24(H2O)4Br4]Br8 (2), [FeIII8CuII6L24(H2O)10](NO3)12 (3), [FeIII8NiII6L24(SCN)11Cl] (4), and [FeIII8CoII6L24(SCN)10(H2O)2]Cl2 (5). The metallic skeleton of each cage describes a cube in which the FeIII ions occupy the eight vertices and the MII ions lie at the center of the six faces. Direct-current magnetic susceptibility and magnetization measurements on 3-5 reveal the presence of weak antiferromagnetic exchange between the metal ions in all three cases. Computational techniques known in theoretical nuclear physics as statistical spectroscopy, which exploit the moments of the Hamiltonian to calculate relevant thermodynamic properties, determine JFe-Cu = 0.10 cm-1 for 3 and JFe-Ni = 0.025 cm-1 for 4. Q-band electron paramagnetic resonance spectra of 1 reveal a significantly wider spectral width in comparison to [FeL3], indicating that the magnitude of the FeIII zero-field splitting is larger in the heterometallic cage than in the monomer.

10.
Dig Dis Sci ; 61(1): 117-25, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26297132

RESUMEN

BACKGROUND: Stool DNA testing represents a potential noninvasive approach to detect upper gastrointestinal (UGI) neoplasms. However, little is known about fecal recovery efficiency of DNA exfoliated from UGI tumors. AIMS: The purpose of this study was to establish a human ingestion model that quantitatively approximates daily cellular shedding from UGI neoplasms and to estimate fecal DNA marker recovery rates. METHODS: Healthy volunteers (n = 10) ingested two scheduled doses of raw salmon, 0.3 and 30 g, simulating the mass exfoliated daily from 1 to 4.5 cm lesions. To approach a steady-state, each dose was ingested over three consecutive days in randomized order. Following defecation of an indicator dye ingested with test meals, stools were collected over 48 h. Ingested salmon DNA was captured from stools using probes targeting pathognomonic Salmonidae sequences (SlmII). Captured DNA was quantified using PCR primers to generate 178, 138, 88 and 55 bp amplicons. RESULTS: SlmII sequences were recovered from all stools following salmon ingestion; recovery was proportional to amount ingested (p = 0.004). Fecal recovery of ingested salmon varied inversely with amplicon size targeted; mean recovery rates of SlmII were 0.49, 0.91, 3.63, and 7.31 copies per 100,000 copies ingested for 178, 134, 88, and 55 bp amplicons, respectively (p < 0.0001). Longer oro-anal transit was associated with reduced recovery. CONCLUSIONS: While recovery efficiencies are low, ingested cellular DNA simulating daily amounts shed from UGI tumors can readily be detected in stool. Assay of shorter-fragment analyte increases recovery. This ingestion model has potential value in studying the effects of perturbations relevant to the fecal recovery of DNA exfoliated from UGI tumors.


Asunto(s)
ADN de Neoplasias/metabolismo , Heces/química , Neoplasias Gastrointestinales/diagnóstico , Reacción en Cadena de la Polimerasa , Salmón/genética , Alimentos Marinos , Animales , ADN de Neoplasias/aislamiento & purificación , Femenino , Neoplasias Gastrointestinales/genética , Neoplasias Gastrointestinales/metabolismo , Voluntarios Sanos , Humanos , Masculino , Valor Predictivo de las Pruebas , Factores de Tiempo
11.
Gastroenterology ; 150(2): 367-79.e1, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26460205

RESUMEN

BACKGROUND & AIMS: In fecal samples from patients with chronic constipation, the microbiota differs from that of healthy subjects. However, the profiles of fecal microbiota only partially replicate those of the mucosal microbiota. It is not clear whether these differences are caused by variations in diet or colonic transit, or are associated with methane production (measured by breath tests). We compared the colonic mucosal and fecal microbiota in patients with chronic constipation and in healthy subjects to investigate the relationships between microbiota and other parameters. METHODS: Sigmoid colonic mucosal and fecal microbiota samples were collected from 25 healthy women (controls) and 25 women with chronic constipation and evaluated by 16S ribosomal RNA gene sequencing (average, 49,186 reads/sample). We assessed associations between microbiota (overall composition and operational taxonomic units) and demographic variables, diet, constipation status, colonic transit, and methane production (measured in breath samples after oral lactulose intake). RESULTS: Fourteen patients with chronic constipation had slow colonic transit. The profile of the colonic mucosal microbiota differed between constipated patients and controls (P < .05). The overall composition of the colonic mucosal microbiota was associated with constipation, independent of colonic transit (P < .05), and discriminated between patients with constipation and controls with 94% accuracy. Genera from Bacteroidetes were more abundant in the colonic mucosal microbiota of patients with constipation. The profile of the fecal microbiota was associated with colonic transit before adjusting for constipation, age, body mass index, and diet; genera from Firmicutes (Faecalibacterium, Lactococcus, and Roseburia) correlated with faster colonic transit. Methane production was associated with the composition of the fecal microbiota, but not with constipation or colonic transit. CONCLUSIONS: After adjusting for diet and colonic transit, the profile of the microbiota in the colonic mucosa could discriminate patients with constipation from healthy individuals. The profile of the fecal microbiota was associated with colonic transit and methane production (measured in breath), but not constipation.


Asunto(s)
Bacterias/metabolismo , Colon/microbiología , Estreñimiento/microbiología , Heces/microbiología , Microbioma Gastrointestinal , Tránsito Gastrointestinal , Mucosa Intestinal/microbiología , Metano/metabolismo , Adulto , Algoritmos , Bacterias/clasificación , Bacterias/genética , Pruebas Respiratorias , Estudios de Casos y Controles , Enfermedad Crónica , Colon/fisiopatología , Estreñimiento/diagnóstico , Estreñimiento/fisiopatología , Femenino , Humanos , Mucosa Intestinal/fisiopatología , Persona de Mediana Edad , Análisis Multivariante , Dinámicas no Lineales , Filogenia , Ribotipificación
12.
Dalton Trans ; 44(48): 20839-42, 2015 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-26599842

RESUMEN

Two new paramagnetic ionic liquids (ILs) comprising a mononuclear iron(III) or manganese(III) complex cation, charge balanced by a dicyanamide anion are reported which show a range of spin states. Both are liquids at room temperature and the Fe(III) based IL exhibits a spin crossover close to 300 K. The spin crossover profile is independent of the solvation, and is both air and moisture stable.

13.
Angew Chem Int Ed Engl ; 54(23): 6761-4, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-25891167

RESUMEN

[Cr(III)8M(II)6](12+) (M(II) =Cu, Co) coordination cubes were constructed from a simple [Cr(III) L3 ] metalloligand and a "naked" M(II) salt. The flexibility in the design proffers the potential to tune the physical properties, as all the constituent parts of the cage can be changed without structural alteration. Computational techniques (known in theoretical nuclear physics as statistical spectroscopy) in tandem with EPR spectroscopy are used to interpret the magnetic behavior.

14.
J Nutr ; 143(5): 672-81, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23486982

RESUMEN

We evaluated the association of dietary fat and protein intake with risk of non-Hodgkin lymphoma (NHL) in a clinic-based study in 603 cases (including 218 chronic lymphocytic leukemia/small lymphocytic lymphoma, 146 follicular lymphoma, and 105 diffuse large B-cell lymphoma) and 1007 frequency-matched controls. Usual diet was assessed with a 128-item food-frequency questionnaire. Unconditional logistic regression was used to estimate ORs and 95% CIs, and polytomous logistic regression was used to assess subtype-specific risks. trans Fatty acid (TFA) intake was positively associated with NHL risk [OR = 1.60 for highest vs. lowest quartile (95% CI = 1.18, 2.15); P-trend = 0.0014], n3 (ω3) fatty acid intake was inversely associated with risk [OR = 0.48 (95% CI = 0.35, 0.65); P-trend < 0.0001], and there was no association with total, animal, plant-based, or saturated fat intake. When examining intake of specific foods, processed meat [OR = 1.37 (95% CI = 1.02, 1.83); P-trend = 0.03], milk containing any fat [OR = 1.47 (95% CI = 1.16, 1.88); P-trend = 0.0025], and high-fat ice cream [OR = 4.03 (95% CI = 2.80, 5.80); P-trend < 0.0001], intakes were positively associated with risk, whereas intakes of fresh fish and total seafood [OR = 0.61 (95% CI = 0.46, 0.80); P-trend = 0.0025] were inversely associated with risk. Overall, there was little evidence for NHL subtype-specific heterogeneity. In conclusion, diets high in TFAs, processed meats, and higher fat dairy products were positively associated with NHL risk, whereas diets high in n3 fatty acids and total seafood were inversely associated with risk.


Asunto(s)
Dieta , Grasas de la Dieta , Ácidos Grasos Omega-3/uso terapéutico , Linfoma no Hodgkin/etiología , Linfoma no Hodgkin/prevención & control , Ácidos Grasos trans/efectos adversos , Adulto , Anciano , Estudios de Casos y Controles , Intervalos de Confianza , Dieta/efectos adversos , Encuestas sobre Dietas , Grasas de la Dieta/efectos adversos , Grasas de la Dieta/uso terapéutico , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/etiología , Leucemia Linfocítica Crónica de Células B/prevención & control , Leucemia Linfoide/etiología , Leucemia Linfoide/prevención & control , Modelos Logísticos , Linfoma de Células B/etiología , Linfoma de Células B/prevención & control , Linfoma Folicular/etiología , Linfoma Folicular/prevención & control , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo , Encuestas y Cuestionarios
15.
J Alzheimers Dis ; 32(2): 329-39, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22810099

RESUMEN

High caloric intake has been associated with an increased risk of cognitive impairment. Total caloric intake is determined by the calories derived from macronutrients. The objective of the study was to investigate the association between percent of daily energy (calories) from macronutrients and incident mild cognitive impairment (MCI) or dementia. Participants were a population-based prospective cohort of elderly persons who were followed over a median 3.7 years (interquartile range, 2.5-3.9) of follow-up. At baseline and every 15 months, participants (median age, 79.5 years) were evaluated using the Clinical Dementia Rating scale, a neurological evaluation, and neuropsychological testing for a diagnosis of MCI, normal cognition, or dementia. Participants also completed a 128-item food-frequency questionnaire at baseline; total daily caloric and macronutrient intakes were calculated using an established database. The percent of total daily energy from protein (% protein), carbohydrate (% carbohydrate), and total fat (% fat) was computed. Among 937 subjects who were cognitively normal at baseline, 200 developed incident MCI or dementia. The risk of MCI or dementia (hazard ratio, [95% confidence interval]) was elevated in subjects with high % carbohydrate (upper quartile: 1.89 [1.17-3.06]; p for trend = 0.004), but was reduced in subjects with high % fat (upper quartile: 0.56 [0.34-0.91]; p for trend = 0.03), and high % protein (upper quartile 0.79 [0.52-1.20]; p for trend = 0.03) in the fully adjusted models. A dietary pattern with relatively high caloric intake from carbohydrates and low caloric intake from fat and proteins may increase the risk of MCI or dementia in elderly persons.


Asunto(s)
Disfunción Cognitiva/etiología , Demencia/etiología , Carbohidratos de la Dieta , Grasas de la Dieta , Proteínas en la Dieta , Ingestión de Energía , Anciano , Anciano de 80 o más Años , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/psicología , Demencia/diagnóstico , Demencia/psicología , Progresión de la Enfermedad , Femenino , Humanos , Estudios Longitudinales , Masculino , Pruebas Neuropsicológicas , Estudios Prospectivos , Riesgo
16.
Urology ; 80(2): 250-4, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22554593

RESUMEN

OBJECTIVE: To identify the effect of a controlled metabolic diet on reducing urinary calcium oxalate (CaOx) supersaturation in subjects with hyperoxaluric nephrolithiasis after potentially malabsorptive forms of bariatric surgery. METHODS: Subjects with a history of CaOx kidney stones and mild hyperoxaluria after bariatric surgery (n = 9) collected baseline 24-hour urine samples while consuming a free choice diet. They were then instructed to consume a controlled diet low in oxalate (70-80 mg/d), normal in calcium (1000 mg/d), and moderate in protein before 2 final 24-hour urine collections. RESULTS: Overall, the urinary CaOx supersaturation decreased from 1.97 ± 0.49 delta Gibbs (DG) with the free choice diet to 1.13 ± 0.75 DG with the controlled diet (P < .01). This occurred in the absence of a significant change in urinary oxalate excretion (0.69 ± 0.29 mmol/d with the free choice diet compared with 0.66 ± 0.38 mmol/d with the controlled diet). Urinary volume, citrate, and pH all increased, although not significantly (P > .05), contributing to the significant CaOx supersaturation change. CONCLUSION: A controlled metabolic diet normal in calcium, moderate in protein, and reduced in oxalate can positively affect urinary CaOx supersaturation after bariatric surgery. However, this diet did not appear to decrease urinary oxalate excretion. Therefore, restriction of dietary oxalate alone might not be enough to reduce urinary oxalate excretion to normal levels in this group of patients with known enteric hyperoxaluria. Additional strategies could be necessary, such as the use of oral calcium supplements as oxalate binders and a lower fat diet.


Asunto(s)
Cirugía Bariátrica , Oxalato de Calcio/metabolismo , Dieta , Oxalatos/orina , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
Int J Cancer ; 131(5): 1158-68, 2012 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22038870

RESUMEN

Antioxidants, primarily from fruits and vegetables, have been hypothesized to protect against non-Hodgkin lymphoma (NHL). The oxygen radical absorbance capacity (ORAC) assay, which measures total antioxidant capacity of individual foods and accounts for synergism, can be estimated using a food-frequency questionnaire (FFQ). We tested the hypothesis that higher intake of antioxidant nutrients from foods, supplements and FFQ-based ORAC values are associated with a lower risk of NHL in a clinic-based study of 603 incident cases and 1,007 frequency-matched controls. Diet was assessed with a 128-item FFQ. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals adjusted for age, sex, residence and total energy. Dietary intake of α-tocopherol (OR=0.50; p-trend=0.0002), ß-carotene (OR=0.58; p-trend=0.0005), lutein/zeaxanthin (OR=0.62; p-trend=0.005), zinc (OR=0.54; p-trend=0.003) and chromium (OR=0.68; p-trend=0.032) was inversely associated with NHL risk. Inclusion of supplement use had little impact on these associations. Total vegetables (OR=0.52; p-trend<0.0001), particularly green leafy (OR=0.52; p-trend<0.0001) and cruciferous (OR=0.68; p-trend=0.045) vegetables, were inversely associated with NHL risk. NHL risk was inversely associated with both hydrophilic ORAC (OR=0.61, p-trend=0.003) and lipophilic ORAC (OR=0.48, p-trend=0.0002), although after simultaneous adjustment for other antioxidants or total vegetables, only the association for lipophilic ORAC remained significant. There was no striking heterogeneity in results across the common NHL subtypes. Higher antioxidant intake as estimated by the FFQ-ORAC, particularly the lipophilic component, was associated with a lower NHL risk after accounting for other antioxidant nutrients and vegetable intake, supporting this as potentially useful summary measure of total antioxidant intake.


Asunto(s)
Antioxidantes/uso terapéutico , Dieta , Frutas , Linfoma no Hodgkin/epidemiología , Linfoma no Hodgkin/prevención & control , Verduras , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Depuradores de Radicales Libres/química , Humanos , Linfoma no Hodgkin/clasificación , Masculino , Persona de Mediana Edad , Minnesota/epidemiología , Pronóstico , Especies Reactivas de Oxígeno/química , Factores de Riesgo , Encuestas y Cuestionarios , alfa-Tocoferol/administración & dosificación , beta Caroteno/administración & dosificación
18.
Kidney Int ; 78(11): 1178-85, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20736987

RESUMEN

We examined the effect of a controlled diet and two probiotic preparations on urinary oxalate excretion, a risk factor for calcium oxalate kidney stone formation, in patients with mild hyperoxaluria. Patients were randomized to a placebo, a probiotic, or a synbiotic preparation. This tested whether these probiotic preparations can increase oxalate metabolism in the intestine and/or decrease oxalate absorption from the gut. Patients were maintained on a controlled diet to remove the confounding variable of differing oxalate intake from food. Urinary oxalate excretion and calcium oxalate supersaturation on the controlled diet were significantly lower compared with baseline on a free-choice diet. Neither study preparation reduced urinary oxalate excretion nor calcium oxalate supersaturation. Fecal lactobacilli colony counts increased on both preparations, whereas enterococcal and yeast colony counts were increased on the synbiotic. Total urine volume and the excretion of oxalate and calcium were all strong independent determinants of urinary calcium oxalate supersaturation. Hence, dietary oxalate restriction reduced urinary oxalate excretion, but the tested probiotics did not influence urinary oxalate levels in patients on a restricted oxalate diet. However, this study suggests that dietary oxalate restriction is useful for kidney stone prevention.


Asunto(s)
Oxalato de Calcio/orina , Dieta , Tracto Gastrointestinal/metabolismo , Hiperoxaluria/terapia , Cálculos Renales/prevención & control , Probióticos/administración & dosificación , Administración Oral , Adulto , Anciano , Biomarcadores/orina , Método Doble Ciego , Heces/microbiología , Femenino , Tracto Gastrointestinal/microbiología , Humanos , Hiperoxaluria/complicaciones , Hiperoxaluria/dietoterapia , Hiperoxaluria/orina , Cálculos Renales/etiología , Cálculos Renales/orina , Modelos Lineales , Masculino , Persona de Mediana Edad , Minnesota , Efecto Placebo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
19.
J Alzheimers Dis ; 21(3): 853-65, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20634591

RESUMEN

Mono- and polyunsaturated fatty acids (MUFA, PUFA) have been associated with a reduced risk of dementia. The association of these fatty acids with mild cognitive impairment (MCI) is not fully established. The objective of the study was to investigate the cross-sectional association of dietary fatty acids with MCI in a population-based sample. Participants aged >or= 70 years on October 1, 2004, were evaluated using the Clinical Dementia Rating Scale (participant and informant), a neurological evaluation, and neuropsychological testing. A panel of nurses, physicians, and neuropsychologists reviewed the data for each participant in order to establish a diagnosis of MCI, normal cognition, or dementia by consensus. Participants also completed a 128-item food-frequency questionnaire. Among 1,233 non-demented subjects, 163 (13.2%) had MCI. The odds ratio (OR) of MCI decreased with increasing PUFA and MUFA intake. Compared to the lowest tertile, the OR (95% confidence interval) for the upper tertiles were 0.44 (0.29-0.66; p for trend = 0.0004) for total PUFA; 0.44 (0.30-0.67; p for trend = 0.0004) for omega-6 fatty acids; 0.62 (0.42-0.91; p for trend = 0.012) for omega-3 fatty acids; and 0.56 (0.38-0.83; p for trend = 0.01) for (MUFA+PUFA):saturated fatty acid ratio after adjustment for age, sex, number of years of education, and caloric intake. In this study, higher intake of PUFA and MUFA was associated with a reduced likelihood of MCI among elderly persons in the population-based setting.


Asunto(s)
Trastornos del Conocimiento/sangre , Grasas de la Dieta/administración & dosificación , Ácidos Grasos Insaturados/administración & dosificación , Ácidos Grasos Insaturados/sangre , Anciano , Anciano de 80 o más Años , Envejecimiento/sangre , Encuestas sobre Dietas , Femenino , Humanos , Masculino , Examen Neurológico , Pruebas Neuropsicológicas , Oportunidad Relativa , Análisis de Regresión , Encuestas y Cuestionarios
20.
Dement Geriatr Cogn Disord ; 29(5): 413-23, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20502015

RESUMEN

BACKGROUND/AIMS: To investigate associations of the Mediterranean diet (MeDi) components and the MeDi score with mild cognitive impairment (MCI). METHODS: Participants (aged 70-89 years) were clinically evaluated to assess MCI and dementia, and completed a 128-item food frequency questionnaire. RESULTS: 163 of 1,233 nondemented persons had MCI. The odds ratio of MCI was reduced for high vegetable intake [0.66 (95% CI = 0.44-0.99), p = 0.05] and for high mono- plus polyunsaturated fatty acid to saturated fatty acid ratio [0.52 (95% CI = 0.33-0.81), p = 0.007], adjusted for confounders. The risk of incident MCI or dementia was reduced in subjects with a high MeDi score [hazard ratio = 0.75 (95% CI = 0.46-1.21), p = 0.24]. CONCLUSION: Vegetables, unsaturated fats, and a high MeDi score may be beneficial to cognitive function.


Asunto(s)
Consumo de Bebidas Alcohólicas/psicología , Trastornos del Conocimiento/epidemiología , Trastornos del Conocimiento/psicología , Dieta Mediterránea , Grasas Insaturadas , Verduras , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Demencia/epidemiología , Demencia/psicología , Encuestas sobre Dietas , Femenino , Humanos , Estudios Longitudinales , Masculino , Pruebas Neuropsicológicas , New York/epidemiología , Escalas de Valoración Psiquiátrica , Encuestas y Cuestionarios
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