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1.
Contemp Clin Trials ; 131: 107274, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37380019

RESUMEN

BACKGROUND: Poor diet quality is an important risk factor for increased asthma prevalence and poor asthma control. To address the question of whether adults with asthma can benefit from following a healthy diet, this trial will test the efficacy and mechanisms of action of a behavioral intervention promoting the Dietary Approaches to Stop Hypertension (DASH) dietary pattern with sodium reduction among patients with uncontrolled asthma. METHODS: In this 2-arm randomized clinical trial, 320 racially/ethnically and socioeconomically diverse adults with uncontrolled asthma on standard controller therapy will be randomized to either a control or an intervention group and assessed at baseline, 3, 6 and 12 months. Control and intervention participants will receive education on lung health, asthma, and other general health topics; additionally, the intervention group will receive DASH behavioral counseling over 12 months. The primary hypothesis is that the DASH behavioral intervention, compared with the education-only control, will lead to significantly more participants with minimum clinically important improvement (responders) in asthma-specific quality of life at 12 months. Secondary hypotheses will test the intervention effects on other asthma (e.g., asthma control, lung function) and non-asthma outcomes (e.g., quality of life). Additionally, therapeutic (e.g., short chain fatty acids, cytokines) and nutritional biomarkers (e.g., dietary inflammatory index, carotenoids) will be assessed to understand the mechanisms of the intervention effect. CONCLUSION: This trial can substantially advance asthma care by providing rigorous evidence on the benefits of a behavioral dietary intervention and mechanistic insights into the role of diet quality in asthma. CLINICALTRIALS: gov #: NCT05251402.


Asunto(s)
Asma , Enfoques Dietéticos para Detener la Hipertensión , Hipertensión , Humanos , Adulto , Calidad de Vida , Dieta , Asma/tratamiento farmacológico , Terapia Conductista/métodos , Hipertensión/epidemiología , Hipertensión/terapia
2.
Environ Sci Atmos ; 1(4): 176-191, 2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-34278306

RESUMEN

A small fraction of aerosol particles known as Ice-Nucleating Particles (INPs) have the potential to trigger ice formation in cloud droplets at higher temperatures than homogeneous freezing. INPs can strongly reduce the water content and albedo of shallow mixed-phase clouds and also influence the development of convective clouds. Therefore, it is important to understand which aerosol types serve as INPs and how effectively they nucleate ice. Using a combination of INP measurements and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS), we quantify both the INP concentrations over a range of activation temperatures and the size-resolved composition. We show that the INP population of aerosol samples collected from an aircraft over the UK during July of 2017 is consistent with ice-nucleation on mineral dust below about -20 °C, but some other INP type must account for ice-nucleation at higher temperatures. Biological aerosol particles above ∼2 µm were detected based on visual detection of their morphological features in all the analysed samples at concentrations of at least 10 to 100 L-1 in the boundary layer. We suggest that given the presence of biological material, it could substantially contribute to the enhanced ice-nucleation ability of the samples at above -20 °C. Organic material attached to mineral dust could be responsible for at least part of this enhancement. These results are consistent with a growing body of data which suggests mineral dust alone cannot explain the INP population in the mid-latitude terrestrial atmosphere and that biological ice nucleating particles are most likely important for cloud glaciation.

3.
Sci Adv ; 6(26): eaba8137, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32637618

RESUMEN

Ice-nucleating particles (INPs) have the potential to remove much of the liquid water in climatically important mid- to high-latitude shallow supercooled clouds, markedly reducing their albedo. The INP sources at these latitudes are very poorly defined, but it is known that there are substantial dust sources across the high latitudes, such as Iceland. Here, we show that Icelandic dust emissions are sporadically an important source of INPs at mid to high latitudes by combining ice-nucleating active site density measurements of aircraft-collected Icelandic dust samples with a global aerosol model. Because Iceland is only one of many high-latitude dust sources, we anticipate that the combined effect of all these sources may strongly contribute to the INP population in the mid- and high-latitude northern hemisphere. This is important because these emissions are directly relevant for the cloud-phase climate feedback and because high-latitude dust emissions are expected to increase in a warmer climate.

5.
Sci Rep ; 8(1): 13821, 2018 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-30217983

RESUMEN

A minute fraction of atmospheric particles exert a disproportionate effect on the phase of mixed-phase clouds by acting as ice-nucleating particles (INPs). To understand the effects of these particles on weather and climate, both now and into the future, we must first develop a quantitative understanding of the major INP sources worldwide. Previous work has demonstrated that aerosols such as desert dusts are globally important INPs, but the role of biogenic INPs is unclear, with conflicting evidence for their importance. Here, we show that at a temperate site all INPs active above -18 °C at concentrations >0.1 L-1 are destroyed on heating, consistent with these INPs being of biological origin. Furthermore, we show that a global model of desert dust INPs dramatically underestimates the measured INP concentrations, but is consistent with the thermally-stable component. Notably, the heat sensitive INPs are active at temperatures where shallow cloud layers in Northern Europe are frequently observed to glaciate. Hence, we suggest that biogenic material is important for primary ice production in this region. The prevalence of heat sensitive, most likely biogenic, INPs in this region highlights that, as a community, we need to quantify the sources and transport of these particles as well as determine their atmospheric abundance across the globe and at cloud altitudes.

6.
Diabetes ; 49(5): 782-8, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10905487

RESUMEN

The purpose of this study was to examine the response of pancreatic beta-cells to changes in insulin sensitivity in women at high risk for type 2 diabetes. Oral glucose tolerance tests (OGTTs) and frequently sampled intravenous glucose tolerance tests (FSIGTs) were conducted on Latino women with impaired glucose tolerance and a history of gestational diabetes before and after 12 weeks of treatment with 400 mg/day troglitazone (n = 13) or placebo (n = 12). Insulin sensitivity was assessed by minimal model analysis, and beta-cell insulin release was assessed as acute insulin responses to glucose (AIRg) and tolbutamide (AIRt) during FSIGTs and as the 30-min incremental insulin response (30-min dINS) during OGTTs. Beta-cell compensation for insulin resistance was assessed as the product (disposition index) of minimal model insulin sensitivity and each of the 3 measures of beta-cell insulin release. In the placebo group, there was no significant change in insulin sensitivity or in any measure of insulin release, beta-cell compensation for insulin resistance, or glucose tolerance. Troglitazone treatment resulted in a significant increase in insulin sensitivity, as reported previously. In response, AIRg did not change significantly, so that the disposition index for AIRg increased significantly from baseline (P = 0.004) and compared with placebo (P = 0.02). AIRt (P = 0.001) and 30-min dINS (P = 0.02) fell with improved insulin sensitivity during troglitazone treatment, so that the disposition index for each of these measures of beta-cell function did not change significantly from baseline (P > 0.20) or compared with placebo (P > 0.3). Minimal model analysis revealed that 89% of the change from baseline in insulin sensitivity during troglitazone treatment was accounted for by lowered plasma insulin concentrations. Neither oral nor intravenous glucose tolerance changed significantly from baseline or compared with placebo during troglitazone treatment. The predominant response of beta-cells to improved insulin sensitivity in women at high risk for type 2 diabetes was a reduction in insulin release to maintain nearly constant glucose tolerance.


Asunto(s)
Cromanos/uso terapéutico , Diabetes Mellitus Tipo 2/etiología , Intolerancia a la Glucosa/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Tiazoles/uso terapéutico , Tiazolidinedionas , Adulto , Diabetes Gestacional/complicaciones , Femenino , Glucosa , Intolerancia a la Glucosa/sangre , Intolerancia a la Glucosa/etiología , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/sangre , Secreción de Insulina , Embarazo , Factores de Riesgo , Tolbutamida , Troglitazona
7.
Diabetes ; 45(11): 1572-9, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8866563

RESUMEN

We conducted a randomized placebo-controlled study to determine the effects of the thiazolidinedione compound troglitazone on whole-body insulin sensitivity (SI), pancreatic beta-cell function, and glucose tolerance in 42 Latino women with impaired glucose tolerance (IGT) and a history of gestational diabetes mellitus (GDM), characteristics that carry an 80% risk of developing NIDDM within 5 years. After baseline oral (OGTT) and intravenous (IVGTT) glucose tolerance testing, subjects were assigned to take placebo or 200 or 400 mg troglitazone daily for 12 weeks (14 subjects per treatment group). An OGTT and IVGTT were repeated during the 12th week of treatment. Five subjects failed to complete the trial for personal reasons, and medication compliance averaged 90% in the remaining subjects, none of whom experienced a serious adverse event. SI, calculated by minimal model analysis of IVGTT results, changed by only 4 +/- 14% during 12 weeks of placebo administration, but increased 40 +/- 22 and 88 +/- 22% above basal during treatment with 200 and 400 mg troglitazone, respectively (P = 0.01 among groups). Troglitazone administration was also associated with a dose-dependent reduction in the total insulin area during IVGTTs, which was highly significant (P < 0.001), and with a reduction during OGTTs, which approached statistical significance (P = 0.09). Glucose tolerance improved slightly in all groups, but the magnitude of change did not differ significantly among groups, whether it was assessed as the number of subjects who continued to manifest IGT at 12 weeks (P = 0.64 among groups), the change in total glucose area during OGTTs (P = 0.58), or the change in fractional glucose disappearance rates during IVGTTs (P = 0.28). Among the women who received troglitazone, the greatest improvement in SI occurred in the women who had the highest diastolic blood pressures and the best IVGTT insulin responses during baseline testing. Our findings indicate that troglitazone improved whole-body insulin sensitivity and lowered circulating insulin concentrations in women with prior GDM who are at very high risk for NIDDM. The lack of improvement in glucose tolerance despite improved insulin sensitivity may be a manifestation of the beta-cell defect that predisposes the women to NIDDM. The overall pattern of response to troglitazone in our high-risk patients indicates that the drug is an ideal agent with which to test whether the amelioration of insulin resistance can delay or prevent diabetes in women with limited beta-cell reserve.


Asunto(s)
Cromanos/uso terapéutico , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Gestacional , Intolerancia a la Glucosa/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Insulina/sangre , Islotes Pancreáticos/metabolismo , Tiazoles/uso terapéutico , Tiazolidinedionas , Adulto , Glucemia/efectos de los fármacos , Presión Sanguínea , Índice de Masa Corporal , California , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Relación Dosis-Respuesta a Droga , Ácidos Grasos no Esterificados/sangre , Femenino , Intolerancia a la Glucosa/sangre , Intolerancia a la Glucosa/fisiopatología , Prueba de Tolerancia a la Glucosa , Hispánicos o Latinos , Humanos , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/efectos de los fármacos , Placebos , Embarazo , Medición de Riesgo , Factores de Riesgo , Tolbutamida , Triglicéridos/sangre , Troglitazona
8.
Gastroenterol Hepatol ; 21(2): 84-7, 1998 Feb.
Artículo en Español | MEDLINE | ID: mdl-9549184

RESUMEN

A case of coeliac disease (CD) and mesenteric lymph node cavitation (MLNC) in a 42-years-old female is presented. The other cases reported in the literature are also reviewed. The most important ganglionar histological features are described and a pathogenic explanation is suggested.


Asunto(s)
Enfermedad Celíaca/complicaciones , Enfermedades Linfáticas/etiología , Mesenterio , Adulto , Femenino , Humanos , Enfermedades Linfáticas/patología , Mesenterio/patología , Persona de Mediana Edad , Enfermedades Peritoneales/etiología , Enfermedades Peritoneales/patología
9.
Arch Latinoam Nutr ; 35(3): 518-35, 1985 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3842057

RESUMEN

Whole flour and milling fractions of raw amaranth seeds were used in 90:10, 80:20 and 50:50 mixtures with industrialized corn flour (MINSA) to prepare tortillas and arepas, basic nutritional foods in several Latin American countries. The three corn-amaranth mixtures showed a good protein and fat content as well as amino acid profile, and presented adequate physical characteristics for making tortillas. Amaranth whole flour and commercial corn flour mixtures in the proportion of 80:20 and 50:50 were found suitable for the preparation of arepas. Protein and fat content were substantially improved, with no changes in organoleptic characteristics. The Mexican type of Amaranthus cruentus, selected due to its availability and bromatologic properties, yielded products of excellent nutritional quality, according to their amino acid content and protein efficiency ratio (PER). The protein-rich (1R) and starchy (2-R) fractions obtained by air classification, also yielded good results when substituting amaranth flour. The afore-mentioned flours and air-classified fractions of the 50:50 mixtures proved to be adequate in gruel preparations when used in 1:8 and 1:12 dilutions, as they improved their organoleptic characteristics. Flakes and extrudates were also used, yielding products with a 13.3-15% protein content, 1.7-3.7% fat, and 65.2-74.2% carbohydrates. In addition, extrudates were utilized to prepare snacks of better nutritional quality than existing similar commercial products. Improvement of the tortilla's mineral and fatty acid contents was achieved in every case. Enrichment of this product with whole amaranth flour is, therefore, recommendable for use in programs aimed at improving the nutritional status of the population.


Asunto(s)
Harina/análisis , Alimentos Fortificados , Magnoliopsida , Zea mays , Amaranthus , Aminoácidos/análisis , Culinaria , Ácidos Grasos/análisis , Manipulación de Alimentos , Alimentos Formulados , Valor Nutritivo , Proteínas de Plantas/análisis
10.
Arch Latinoam Nutr ; 35(4): 603-19, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3842924

RESUMEN

Forty-five harvests corresponding to the two predominating domestic species of amaranth in Mexico were studied. The proximate analysis revealed some statistically significant differences throughout three years of observation. The Ca, P and Fe content did not vary greatly in 15 samples. No chemical differences were either manifested in the Mercado and Aztec types of A. hypochondriacus, nor in the Mexican type of A. cruentus. The latter exhibits a higher grain yield and a shorter life cycle; however, its baking quality is apparently inferior to that of the Mercado type of A. hypochondriacus. The heat treatment of the seeds (toasting, popping and cooking) affected protein and lysine contents as does in cereals and leguminous seeds although toasting in particular improves its sensory characteristics without altering digestibility and PER. Popping only improves PER. Heating at 90 or 170 degrees C for three to five minutes, at the usual seed's moisture rate of 6 to 15%, does not affect protein content and does so only slightly in the case of the fatty acids content. Amylographic and farinographic values of the starchy fractions indicate similarities to C. quinoa and differences with respect to wheat. In the case of "amaranth milk", viscosity and gelatinization temperature produced satisfactory values. The extension of amaranth cultivation in the country is hereby suggested in view of the seed's nutritional quality, and considering the behavior of whole amaranth flour and its fractions.


Asunto(s)
Harina , Manipulación de Alimentos , Magnoliopsida , Semillas , Amaranthus , Calcio/análisis , Ácidos Grasos/análisis , Harina/análisis , Calor , Fósforo/análisis , Proteínas de Plantas/análisis , Reología , Semillas/análisis
11.
Arch Latinoam Nutr ; 35(4): 620-30, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3842925

RESUMEN

The different milling characteristics of Amaranthus cruentus, a domestic variety prevailing in Mexico, selected as representative sample, are herein discussed. This was subjected to proximate analysis, which confirmed its good quality. Milling trials were carried out for the preparation of whole flour by means of conventional mills and by combining some of these with the Raymond and Alpine separators for air classification. Results were then compared to those obtained with a Strong-Scott pearler. Grits and bran contained the highest protein concentration. After comparing overall results, it may be concluded that the best operating conditions are the following: a) seed pearling using five passes, in a pearler, with variable yields of approximately 22% containing 36% protein, and b) combining the Miag mill and Raymond air separator, with variable yields of approximately 32% and a protein content of 30-36%. Proximate analysis of the fractions as well as farinographic and amylographic characteristics--different from those of whole wheat and amaranth flours--suggest their use in the preparation of nutritionally-enriched food products.


Asunto(s)
Harina , Manipulación de Alimentos , Magnoliopsida , Semillas , Amaranthus , Harina/análisis , Alimentos Fortificados , Calor , Valor Nutritivo , Proteínas de Plantas/análisis , Semillas/análisis
12.
Arch Latinoam Nutr ; 37(3): 480-93, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3506402

RESUMEN

A powdered blend for feeding preschool children was prepared from whole amaranth (Amaranthus cruentus) seeds, pearled oats, soybeans, sucrose and vegetable oil. The blend was similar in proximal chemical analysis and total caloric content, and identical in calorie distribution and vitamin and mineral patterns to a soy/oats infant formula previously developed. The amaranth blend equalled the FAO/WHO 1973 children's pattern in tryptophan and exceeded this pattern, as well as the soy/oats formula in all other essential amino acids; it reflected higher PER than casein and the soy/oats formula. In feeding trials with children 1-3 years of age, no significant differences in weight gain was observed when either product was fed. The anticipated cost of the amaranth blend is 6% lower than that of the soy/oats formula.


Asunto(s)
Fenómenos Fisiológicos Nutricionales Infantiles , Grano Comestible , Alimentos Formulados , Verduras , Amaranthus , Aminoácidos/análisis , Peso Corporal , Preescolar , Costos y Análisis de Costo , Alimentos Formulados/análisis , Alimentos Formulados/economía , Humanos , Lactante , Minerales/análisis , Valor Nutritivo , Glycine max , Vitaminas/análisis
20.
Gac Med Mex ; 133 Suppl 1: 35-41, 1997.
Artículo en Español | MEDLINE | ID: mdl-9580106
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