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BACKGROUND AND METHODS: Pancreatico-duodenectomy (PD) carries significant morbidity and mortality, with very few modifiable risk factors. Radiological evidence of sarcopenia is associated with poor outcomes. This retrospective study aimed to analyse the relationship between easy-to-use bedside nutritional assessment techniques and radiological markers of muscle loss to identify those patients most likely to benefit from prehabilitation. RESULTS: Data were available in 184 consecutive patients undergoing PD. Malnutrition was present in 33-71%, and 48% had a high visceral fat-to-skeletal muscle ratio, suggestive of sarcopenic obesity (SO). Surgical risk was higher in patients with obesity (OR 1.07, 95%CI 1.01-1.14, p = 0.031), and length of stay was 5 days longer in those with SO (p = 0.006). There was no correlation between skeletal muscle and malnutrition using percentage weight loss or the malnutrition universal screening tool (MUST), but a weak correlation between the highest hand grip strength (HGS; 0.468, p < 0.001) and the Global Leadership in Malnutrition (GLIM) criteria (-0.379, p < 0.001). CONCLUSIONS: Nutritional assessment tools give widely variable results. Further research is needed to identify patients at significant nutritional risk prior to PD. In the meantime, those with malnutrition (according to the GLIM criteria), obesity or low HGS should be referred to prehabilitation.
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Desnutrición , Músculo Esquelético , Evaluación Nutricional , Estado Nutricional , Pancreaticoduodenectomía , Sarcopenia , Humanos , Masculino , Femenino , Estudios Retrospectivos , Sarcopenia/etiología , Sarcopenia/diagnóstico , Anciano , Desnutrición/diagnóstico , Desnutrición/etiología , Persona de Mediana Edad , Pancreaticoduodenectomía/efectos adversos , Fuerza de la Mano , Obesidad/cirugía , Obesidad/complicaciones , Factores de Riesgo , Anciano de 80 o más AñosRESUMEN
Specific food supplements are essential during preconception and pregnancy to ensure adequate intake of vitamins and minerals to support fetal growth and development and metabolic changes in the maternal body. Our objective was to identify food supplement recommendations, particularly those of folic acid, iron, Vitamin D, and iodine, during preconception and/or pregnancy across a geographically diverse range of countries. Further, we investigated whether country location and income-level related to the recommendations. We performed an electronic search and identified country-specific preconception and pregnancy food supplement recommendations, policy documents, and official guidelines of national organizations informing recommendations. To ensure the data were as accurate as possible, country-specific experts were contacted. Data were collected in 2017 and reevaluated in 2022. Country income level was determined by the World Bank classification. Each inspected country (n = 43) recommended folic acid supplementation, typically 400 µg/day, before and during pregnancy. About half of the countries recommended an iron supplement (dose range, 16-195 mg/day) and one quarter Vitamin D (typically 10 µg/d in higher latitudes) and iodine (150-200 µg/day). Country location and income level had some influence on the recommendations. Vitamin D was more often recommended in higher latitude, high-income countries. Almost all upper-middle and lower-middle income countries recommended iron supplementation, whereas less than one third of high-income countries had a corresponding recommendation. Findings suggest that food supplement recommendations for pregnant women vary across countries, likely influenced by geographic location as well as income level. These data may be used in the harmonization of food supplement recommendations.
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Suplementos Dietéticos , Ácido Fólico , Yodo , Micronutrientes , Humanos , Femenino , Embarazo , Micronutrientes/administración & dosificación , Ácido Fólico/administración & dosificación , Yodo/administración & dosificación , Yodo/deficiencia , Vitamina D/administración & dosificación , Ingesta Diaria Recomendada , Política Nutricional , Fenómenos Fisiologicos Nutricionales MaternosRESUMEN
PURPOSE: Cow's milk is the primary source of iodine in the UK, but consumption of plant-based milk alternatives (PBMA) is increasing and these products are often not fortified with iodine. We evaluated the impact that replacing current milk consumption with PBMA would have on iodine intake. METHODS: We used data from the National Diet and Nutrition Survey (2016-2019) for children (1.5-10 years), girls 11-18 years, and women of reproductive age (WRA). We used a dietary modelling approach with scenarios using brand-level iodine-fortification data (0, 13, 22.5, 27.4 and 45 µg/100 mL). Relative to usual diet, we calculated change in iodine intake, and the proportion with intake below the Lower Reference Nutrient Intake (LRNI) or above the upper limit. RESULTS: For all groups, replacement with PBMA, either unfortified or fortified at the lowest concentration, resulted in a meaningful decrease in iodine intake, and increased the proportion with intake < LRNI; compared to usual diet, iodine intake reduced by 58% in children 1.5-3 years (127 vs. 53 µg/day) and the proportion with intake < LRNI increased in girls (11-18 years; 20% to 48%) and WRA (13% to 33%) if an unfortified PBMA was used. Replacement of milk with PBMA fortified at 27.4 µg/100 mL had the lowest impact. CONCLUSION: Replacing milk with commercially available PBMAs has potential to reduce population iodine intake, depending on the fortification level. PBMAs fortified with ≥ 22.5 and < 45 µg iodine/100 mL would be required to minimize the impact on iodine intake. Research is needed on the impact of total dairy replacement.
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Yodo , Leche , Ácidos Polimetacrílicos , Niño , Animales , Bovinos , Humanos , Femenino , Dieta , Estado Nutricional , Alimentos FortificadosRESUMEN
The dual burden of malnutrition is characterised by the coexistence of undernutrition alongside overweight/obesity and diet-related noncommunicable diseases. It is a paradox which disproportionately affects women and is applicable to those who become pregnant after weight loss surgery. Obesity before and during pregnancy is associated with increased risk of adverse perinatal outcomes in both mother and child. Overall lifestyle interventions targeting weight loss in the preconception period have not proven effective, with people, and women in particular, increasingly seeking weight loss surgery. In women with severe obesity, surgery may normalise hormonal abnormalities and improve fertility. In those who become pregnant after surgery, evidence suggests a better overall obstetric outcome compared to those with severe obesity managed conservatively; however, there is heightened risk of maternal nutritional deficiencies and infants born small for gestational age. Specifically, pregnancy soon after surgery, in the catabolic phase when rapid weight loss is occurring, has the potential for poor outcomes. Lifelong micronutrient supplementation is required, and there is considerable risk of malnutrition if nutritional aftercare guidelines are not adhered to. It is therefore recommended that pregnancy is delayed until a stable weight is achieved and is supported by individualised advice from a multidisciplinary team. Further research is required to better understand how weight loss surgery affects the chances of having a healthy pregnancy and to ultimately improve nutritional management and patient care. In this review, we aim to summarise the evidence and guidance around nutrition during pregnancy after weight loss surgery.
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To investigate how disulfide bonds can impact protein energy landscapes, we surveyed the effects of adding or removing a disulfide in two ß-lactamase enzymes, TEM-1 and CTX-M-9. The homologs share a structure and 38% sequence identity, but only TEM-1 contains a native disulfide bond. They also differ in thermodynamic stability and in the number of states populated at equilibrium: CTX-M-9 is two-state whereas TEM-1 has an additional intermediate state. We hypothesized that the disulfide bond is the major underlying determinant for these observed differences in their energy landscapes. To test this, we removed the disulfide bridge from TEM-1 and introduced a disulfide bridge at the same location in CTX-M-9. This modest change to sequence modulates the stabilities-and therefore populations-of TEM-1's equilibrium states and, more surprisingly, creates a novel third state in CTX-M-9. Unlike TEM-1's partially folded intermediate, this third state is a higher-order oligomer with reduced cysteines that retains the native fold and is fully active. Sub-denaturing concentrations of urea shifts the equilibrium to the monomeric form, allowing the disulfide bond to form. Interestingly, comparing the stability of the oxidized monomer with a variant lacking cysteines reveals the disulfide is neither stabilizing nor destabilizing in CTX-M-9, in contrast with the observed stabilization in TEM-1. Thus, we can conclude that engineering disulfide bonds is not always an effective stabilization strategy even when analogous disulfides exist in more stable structural homologs. This study also illustrates how homo-oligomerization can result from a small number of mutations, suggesting complex formation might be easily accessed during a protein family's evolution.
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Proteínas de Escherichia coli , Pliegue de Proteína , beta-Lactamasas/química , Cisteína , Disulfuros/químicaRESUMEN
An increasing number of food-based recommendations promote a plant-based diet to address health concerns and environmental sustainability in global food systems. As the main sources of iodine in many countries are fish, eggs and dairy products, it is unclear whether plant-based diets, such as the EAT-Lancet reference diet, would provide sufficient iodine. This is important as iodine, through the thyroid hormones, is required for growth and brain development; adequate iodine intake is especially important before, and during, pregnancy. In this narrative review, we evaluated the current literature and estimated iodine provision from the EAT-Lancet reference diet. There is evidence that those following a strict plant-based diet, such as vegans, cannot reach the recommended iodine intake from food alone and are reliant on iodine supplements. Using the EAT-Lancet reference diet intake recommendations in combination with iodine values from UK food tables, we calculated that the diet would provide 128 µg/d (85 % of the adult recommendation of 150 µg/d and 5164 % of the pregnancy recommendation of 200250 µg/d). However, if milk is replaced with unfortified plant-based alternatives, total iodine provision would be just 54 µg/d (34 % and 2227 % of the recommendations for adults and pregnancy, respectively). Plant-based dietary recommendations might place consumers at risk of iodine deficiency in countries without a fortification programme and where animal products provide the majority of iodine intake, such as the UK and Norway. It is essential that those following a predominantly plant-based diet are given appropriate dietary advice to ensure adequate iodine intake.
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Yodo , Femenino , Embarazo , Animales , Yodo/análisis , Dieta a Base de Plantas , Dieta , Estado Nutricional , Leche/químicaRESUMEN
The Childhood Obesity Plan aimed to reduce sugar and energy in foods through a voluntary sugar-reduction programme. Our primary objective was to determine whether this implementation strategy had been successful, focusing on the out-of-home sector. We used a repeated cross-sectional design to evaluate nutritional changes in desserts served by leading chain restaurants. We extracted nutrition information from online menus in autumn/winter 2020, for comparison with baseline (2017) and interim (2018) values extracted from third-party datasets. We assessed compliance with the 20% sugar-reduction target and category-specific energy targets by product category and for pooled desserts. Overall, sugar/portion and energy/portion decreased by 11% and 4%, respectively. Policy targets were achieved in one of five categories (ice-cream: -38% sugar, p < 0.001; -30% energy, p < 0.001). Secondary outcomes were analysed for subgroups with the necessary data. Few chains significantly reduced sugar and/or energy across their dessert range. Energy/portion was positively associated with portion weight and sugar/portion but not with sugar/100 g. More than half of adults' desserts contained excessive sugar and/or saturated fat compared with dietary guidelines. Children's desserts less frequently exceeded guidelines. These results demonstrate that voluntary measures can drive substantial change when technical, commercial, and operational barriers can be overcome.
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Obesidad Infantil , Adulto , Humanos , Niño , Estudios Transversales , Obesidad Infantil/epidemiología , Obesidad Infantil/prevención & control , Alimentos , Política Nutricional , Azúcares , Valor Nutritivo , Ingestión de EnergíaRESUMEN
Pancreatico-duodenectomy (PD) includes resection of the duodenum and use of the proximal jejunum in a blind loop, thus reducing the absorptive capacity for vitamins and minerals. Several studies have analysed the frequency of micronutrient deficiencies, but there is a paucity of data on those taking routine supplements. A retrospective review of medical notes was undertaken on 548 patients under long-term follow-up following PD in a tertiary hepato-pancreatico-biliary centre. Data were available on 205 patients from 1-14 years following PD, and deficiencies were identified as follows: vitamin A (3%), vitamin D (46%), vitamin E (2%), iron (42%), iron-deficiency anaemia (21%), selenium (3%), magnesium (6%), copper (1%), and zinc (44%). Elevated parathyroid hormone was present in 11% of cases. There was no significant difference over time (p > 0.05). Routine supplementation with a vitamin and mineral supplement did appear to reduce the incidence of biochemical deficiency in vitamin A, vitamin E, and selenium compared to published data. However, iron, vitamin D, and zinc deficiencies were prevalent despite supplementation and require surveillance.
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Desnutrición , Selenio , Humanos , Vitamina A , Micronutrientes , Vitaminas , Suplementos Dietéticos , Vitamina D , Hierro , Vitamina E , ZincRESUMEN
BACKGROUND: Obesity can negatively influence quality of life (QoL). Polycystic ovarian syndrome (PCOS), associated with obesity, presents with sub-fertility, hyperandrogenism, and/or insulin resistance. These features can also negatively influence QoL. This study aimed to determine whether bariatric surgery improves QoL in women of reproductive age, with and without PCOS. We hypothesized greater QoL improvements would be seen post-operatively in women with PCOS. METHODS: Women undergoing bariatric surgery (N.=77) completed questionnaires exploring health-related quality of life (HR-QoL) prior to and at 3, 6 and 12 months post-surgery. Weight loss, symptoms, and association with change in QoL were assessed. RESULTS: Bariatric surgery resulted in significant QoL improvements, independent of PCOS status. Oligo/amenorrhea was reported in 68% of women at baseline, decreasing to 35% by 12 months. Sixty-five percent of women whose menstrual irregularity resolved over follow-up had PCOS. Hirsutism was reported in 64% of women at baseline (all of whom had PCOS), decreasing to 19% by 12 months. Weight loss at 12-months was 45.8±20.7 kg for women without PCOS compared to 44.3±16.8 kg in women with PCOS (P=0.07). Weight loss was moderately associated with 12-month QoL improvements for both groups. CONCLUSIONS: Bariatric surgery provides significant physical and psychological health benefits for women with obesity both with and without PCOS. Surgery can also ameliorate the clinical syndrome of PCOS, including oligomenorrhoea, hirsutism, and subfertility, with subsequent QoL benefits. Psychological support perioperatively may aid QoL outcomes by acknowledging factors influencing QoL beside absolute weight loss.
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Cirugía Bariátrica , Obesidad , Síndrome del Ovario Poliquístico , Femenino , Humanos , Cirugía Bariátrica/psicología , Estudios de Cohortes , Obesidad/complicaciones , Obesidad/cirugía , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/cirugía , Síndrome del Ovario Poliquístico/psicología , Calidad de VidaRESUMEN
Milk, dairy products, and fish are the main sources of iodine in the UK. Plant-based products are increasingly popular, especially with young women, which may affect iodine intake as they are naturally low in iodine; this is concerning as iodine is required for fetal brain development. We, aimed to (i) assess the iodine fortification of products sold as alternatives to milk, yoghurt, cheese and fish through a cross-sectional survey of UK retail outlets in 2020, and (ii) model the impact of substitution with such products on iodine intake, using portion-based scenarios. We identified 300 products, including plant-based alternatives to: (i) milk (n 146); (ii) yoghurt (n 76); (iii) cheese (n 67) and (iv) fish (n 11). After excluding organic products (n 48), which cannot be fortified, only 28 % (n 29) of milk alternatives and 6 % (n 4) of yoghurt alternatives were fortified with iodine, compared with 88 % (n 92) and 73 % (n 51), respectively, with Ca. No cheese alternative was fortified with iodine, but 55 % were fortified with Ca. None of the fish alternatives were iodine fortified. Substitution of three portions of dairy product (milk/yoghurt/cheese) per day with unfortified alternatives would reduce the iodine provided by 97·9 % (124 v. 2·6 µg) and substantially reduce the contribution to the adult intake recommendation (150 µg/d; 83 v. 1·8 %). Our study highlights that the majority of plant-based alternatives are not iodine fortified and that the use of unfortified alternatives put consumers at risk of iodine deficiency.
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Yodo , Animales , Femenino , Estudios Transversales , Alimentos Fortificados , Leche , Productos Lácteos , Peces , Reino UnidoRESUMEN
AI-based software applications for personalized nutrition have recently gained increasing attention to help users follow a healthy lifestyle. In this paper, we present a knowledge-based recommendation framework that exploits an explicit dataset of expert-validated meals to offer highly accurate diet plans spanning across ten user groups of both healthy subjects and participants with health conditions. The proposed advisor is built on a novel architecture that includes (a) a qualitative layer for verifying ingredient appropriateness, and (b) a quantitative layer for synthesizing meal plans. The first layer is implemented as an expert system for fuzzy inference relying on an ontology of rules acquired by experts in Nutrition, while the second layer as an optimization method for generating daily meal plans based on target nutrient values and ranges. The system's effectiveness is evaluated through extensive experiments for establishing meal and meal plan appropriateness, meal variety, as well as system capacity for recommending meal plans. Evaluations involved synthetic data, including the generation of 3000 virtual user profiles and their weekly meal plans. Results reveal a high precision and recall for recommending appropriate ingredients in most user categories, while the meal plan generator achieved a total recommendation accuracy of 92% for all nutrient recommendations.
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Dieta Saludable , Comidas , Humanos , Dieta , Estado Nutricional , Inteligencia ArtificialRESUMEN
The aim was to investigate, among pregnant women, (1) the use of food supplements and (2) the awareness of food supplement recommendations and beliefs about food supplement use in four European countries: Finland, Italy, Poland, and the United Kingdom. The participants (n = 1804) completed an online questionnaire with predefined statements. Daily intakes of vitamins and minerals were calculated using uploaded pictures or weblinks of the supplement packages. Country differences were assessed. Most participants (91%) used at least one food supplement during pregnancy. A prenatal multivitamin was the most commonly used supplement type (84% of the users), and 75% of the participants thought consumption of multivitamin is recommended. Of the participants, 81% knew that folic acid is recommended during pregnancy while 58% knew the recommendation for vitamin D. In 19% of the supplement users, the daily safe upper intake limit of at least one nutrient was exceeded. Nevertheless, most participants agreed that they knew which supplements (91%) and doses of supplements (87%) needed to be used during pregnancy. To conclude, the majority of the participants used food supplements, but lower proportions knew and adhered to the recommended intakes. Between-country differences were observed in the use and knowledge of and beliefs regarding supplements. The results suggest a need for assessment and monitoring of supplement use in antenatal care to ensure appropriate use.
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Suplementos Dietéticos , Mujeres Embarazadas , Femenino , Humanos , Minerales , Embarazo , Encuestas y Cuestionarios , VitaminasRESUMEN
The ubiquitous nature of smartphone ownership, its broad application and usage, along with its interactive delivery of timely feedback are appealing for health-related behavior change interventions via mobile apps. However, users' perspectives about such apps are vital in better bridging the gap between their design intention and effective practical usage. In this vein, a modified technology acceptance model (mTAM) is proposed here, to explain the relationship between users' perspectives when using an AI-based smartphone app for personalized nutrition and healthy living, namely, PROTEIN, and the mTAM constructs toward behavior change in their nutrition and physical activity habits. In particular, online survey data from 85 users of the PROTEIN app within a period of 2 months were subjected to confirmatory factor analysis (CFA) and regression analysis (RA) to reveal the relationship of the mTAM constructs, i.e., perceived usefulness (PU), perceived ease of use (PEoU), perceived novelty (PN), perceived personalization (PP), usage attitude (UA), and usage intention (UI) with the users' behavior change (BC), as expressed via the acceptance/rejection of six related hypotheses (H1-H6), respectively. The resulted CFA-related parameters, i.e., factor loading (FL) with the related p-value, average variance extracted (AVE), and composite reliability (CR), along with the RA results, have shown that all hypotheses H1-H6 can be accepted (p < 0.001). In particular, it was found that, in all cases, FL > 0.5, CR > 0.7, AVE > 0.5, indicating that the items/constructs within the mTAM framework have good convergent validity. Moreover, the adjusted coefficient of determination (R 2) was found within the range of 0.224-0.732, justifying the positive effect of PU, PEoU, PN, and PP on the UA, that in turn positively affects the UI, leading to the BC. Additionally, using a hierarchical RA, a significant change in the prediction of BC from UA when the UI is used as a mediating variable was identified. The explored mTAM framework provides the means for explaining the role of each construct in the functionality of the PROTEIN app as a supportive tool for the users to improve their healthy living by adopting behavior change in their dietary and physical activity habits. The findings herein offer insights and references for formulating new strategies and policies to improve the collaboration among app designers, developers, behavior scientists, nutritionists, physical activity/exercise physiology experts, and marketing experts for app design/development toward behavior change.
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Targeted drug delivery to disease-associated activated neutrophils can provide novel therapeutic opportunities while avoiding systemic effects on immune functions. We created a nanomedicine platform that uniquely utilizes an α1-antitrypsin-derived peptide to confer binding specificity to neutrophil elastase on activated neutrophils. Surface decoration with this peptide enabled specific anchorage of nanoparticles to activated neutrophils and platelet-neutrophil aggregates, in vitro and in vivo. Nanoparticle delivery of a model drug, hydroxychloroquine, demonstrated significant reduction of neutrophil activities in vitro and a therapeutic effect on murine venous thrombosis in vivo. This innovative approach of cell-specific and activation-state-specific targeting can be applied to several neutrophil-driven pathologies.
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Elastasa de Leucocito , Deficiencia de alfa 1-Antitripsina , Animales , Humanos , Hidroxicloroquina/farmacología , Elastasa de Leucocito/metabolismo , Ratones , Nanomedicina , NeutrófilosRESUMEN
Processed foods are increasingly under the spotlight since the development of classification systems based on proxies for food processing. Published critical reviews and commentaries suggest different views among professional disciplines about the definition and classification of processed food. There is a need to further understand perspectives of professionals on the conceptualisation of processed food and the agreements and disagreements among experts, to encourage interdisciplinary dialogue and aid communication to the public. The aim of this research was to elicit views and understandings of professionals on processed food, their perceptions of lay people's perceptions of the same, and their perspectives on the challenges of communicating about processed foods to the public. The online discussion groups brought together a range of professionals (n = 27), covering the fields of nutrition, food technology, policy making, industry, and civil society, mixed in 5 heterogenous groups. Through thematic analysis the following themes relating to the conceptualisation of processed food and challenges for communication were identified: (1) Broad concepts that need differentiation; (2) Disagreements on scope and degree of processing; (3) The role of food processing within the food system: the challenges in framing risks and benefits; and (4) The challenge of different perspectives and interests for risk communication. Throughout the discussions blurred lines in the characterisation of processing, processed foods, and unhealthy foods were observed. Participants agreed that consensus is important, but difficult. Participants identified a need for further interdisciplinary dialogue, including public engagement, to break down the observed issues, and work towards a mutual understanding and develop clear communication messages.
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Vitamin D is best known for its role in maintaining bone health and calcium homeostasis. However, it also exerts a broad range of extra-skeletal effects on cellular physiology and on the immune system. Vitamins D2 and D3 share a high degree of structural similarity. Functional equivalence in their vitamin D-dependent effects on human physiology is usually assumed but has in fact not been well defined experimentally. In this study we seek to redress the gap in knowledge by undertaking an in-depth examination of changes in the human blood transcriptome following supplementation with physiological doses of vitamin D2 and D3. Our work extends a previously published randomized placebo-controlled trial that recruited healthy white European and South Asian women who were given 15 µg of vitamin D2 or D3 daily over 12 weeks in wintertime in the UK (Nov-Mar) by additionally determining changes in the blood transcriptome over the intervention period using microarrays. An integrated comparison of the results defines both the effect of vitamin D3 or D2 on gene expression, and any influence of ethnic background. An important aspect of this analysis was the focus on the changes in expression from baseline to the 12-week endpoint of treatment within each individual, harnessing the longitudinal design of the study. Whilst overlap in the repertoire of differentially expressed genes was present in the D2 or D3-dependent effects identified, most changes were specific to either one vitamin or the other. The data also pointed to the possibility of ethnic differences in the responses. Notably, following vitamin D3 supplementation, the majority of changes in gene expression reflected a down-regulation in the activity of genes, many encoding pathways of the innate and adaptive immune systems, potentially shifting the immune system to a more tolerogenic status. Surprisingly, gene expression associated with type I and type II interferon activity, critical to the innate response to bacterial and viral infections, differed following supplementation with either vitamin D2 or vitamin D3, with only vitamin D3 having a stimulatory effect. This study suggests that further investigation of the respective physiological roles of vitamin D2 and vitamin D3 is warranted.
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Ergocalciferoles , Transcriptoma , Colecalciferol/uso terapéutico , Suplementos Dietéticos , Femenino , Humanos , Sistema Inmunológico , Vitamina D/farmacología , Vitaminas/uso terapéuticoRESUMEN
Thermodynamic stability represents one important constraint on protein evolution, but the molecular basis for how mutations that change stability impact fitness remains unclear. Here, we demonstrate that a prevalent global suppressor mutation in TEM ß-lactamase, M182T, increases fitness by reducing proteolysis in vivo. We also show that a synthetic mutation, M182S, can act as a global suppressor and suggest that its absence from natural populations is due to genetic inaccessibility rather than fundamental differences in the protein's stability or activity.
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Escherichia coli , Supresión Genética , Escherichia coli/genética , Escherichia coli/metabolismo , Evolución Molecular , Mutación , Termodinámica , beta-Lactamasas/genética , beta-Lactamasas/metabolismoRESUMEN
Breastfeeding has many known benefits, but rates vary globally. We propose two main reasons why psychological theory and interventions have not been successful to date in explaining breastfeeding behaviours. Specifically, prior research underestimates the importance of (1) specific emotions and (2) wider injunctive influences (i.e., societal and moral norms about what women feel they ought to be doing) in the breastfeeding experience. Therefore, we conducted a systematic review of quantitative, qualitative, and mixed-methods studies that explored whether injunctive norms and/ or specific emotions are associated with breastfeeding behaviours (i.e., intentions, initiation and duration). Seventy-two papers were included in this review; data were extracted and quality appraisals conducted for all included studies. A meta-analysis of effect sizes was performed with the quantitative data. A convergent qualitative synthesis of the data was conducted, resulting in the following line of argument: Breastfeeding is a social behaviour and not a personal/individual behaviour. From this line of argument, three themes with associated sub-themes were developed, highlighting the importance of both specific emotions and injunctive norms on breastfeeding behaviours. These influences are discussed in relation to both theoretical and practical implications, as well as future research.
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Lactancia Materna , Intención , Lactancia Materna/psicología , Emociones , Femenino , Humanos , Conducta Social , Normas SocialesRESUMEN
BACKGROUND/OBJECTIVES: Vitamin D deficiency remains a global public health issue, particularly in minority ethnic groups. This review investigates the vitamin D status (as measured by 25(OH)D and dietary intake) of the African-Caribbean population globally. SUBJECTS/METHODS: A systematic review was conducted by searching key databases (PUBMED, Web of Science, Scopus) from inception until October 2019. Search terms included 'Vitamin D status' and 'African-Caribbean'. A random effects and fixed effects meta-analysis was performed by combining means and standard error of the mean. RESULT: The search yielded 19 papers that included n = 5670 African-Caribbean participants from six countries. A meta-analysis found this population to have sufficient (>50 nmol/L) 25(OH)D levels at 67.8 nmol/L, 95% CI (57.9, 7.6) but poor dietary intake of vitamin D at only 3.0 µg/day, 95% CI (1.67,4.31). For those living at low latitudes 'insufficient' (as defined by study authors) 25(OH)D levels were found only in participants with type 2 diabetes and in those undergoing haemodialysis. Suboptimal dietary vitamin D intake (according to the UK recommended nutrient intake of 10 µg/day) was reported in all studies at high latitudes. Studies at lower latitudes, with lower recommended dietary intakes (Caribbean recommended dietary intake: 2.5 µg/day) found 'sufficient' intake in two out of three studies. CONCLUSIONS: 25(OH)D sufficiency was found in African-Caribbean populations at lower latitudes. However, at higher latitudes, 25(OH)D deficiency and low dietary vitamin D intake was prevalent.
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Diabetes Mellitus Tipo 2 , Deficiencia de Vitamina D , Suplementos Dietéticos , Humanos , Estaciones del Año , Vitamina D , Deficiencia de Vitamina D/epidemiología , VitaminasRESUMEN
Recent interest in the gut-brain-axis has highlighted the potential of prebiotics to impact wellbeing, and to affect behavioral change in humans. In this clinical trial, we examined the impact of four-weeks daily supplementation of galacto-oligosaccharides (GOS) on self-reported nutrient intake and relationships on gut microbiota in a four-week two-armed parallel double-blind placebo controlled GOS supplement trial in young adult females. Food diaries and stool samples were collected prior to and following 28 days of supplement consumption. It was found that four weeks of GOS supplementation influenced macronutrient intake, as evident by reduced carbohydrate and sugars and increased fats intake. Further analysis showed that the reduction in carbohydrates was predicted by increasing abundances of Bifidobacterium in the GOS group in comparison to the placebo group. This suggests that Bifidobacterium increase via GOS supplementation may help improve the gut microbiota composition by altering the desire for specific types of carbohydrates and boosting Bifidobacterium availability when fiber intake is below recommended levels, without compromising appetite for fiber from food.