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DNA methylation is a key component of the epigenetic machinery that is responsible for regulating gene expression and, therefore, cell function. Patterns of DNA methylation change during development and ageing, differ between cell types, are altered in multiple diseases and can be modulated by dietary factors. However, evidence about the effects of dietary factors on DNA methylation patterns in humans is fragmentary. This study was initiated to collate evidence for causal links between dietary factors and changes in DNA methylation patterns. We carried out a systematic review of dietary intervention studies in adult humans using Medline, EMBASE and Scopus. Out of 22 149 screened titles, sixty intervention studies were included, of which 65% were randomised (n 39). Most studies (53%) reported data from blood analyses, whereas 27% studied DNA methylation in colorectal mucosal biopsies. Folic acid was the most common intervention agent (33%). There was great heterogeneity in the methods used for assessing DNA methylation and in the genomic loci investigated. Meta-analysis of the effect of folic acid on global DNA methylation revealed strong evidence that supplementation caused hypermethylation in colorectal mucosa (P=0·009). Meta-regression analysis showed that the dose of supplementary folic acid was the only identified factor (P<0·001) showing a positive relationship. In summary, there is limited evidence from intervention studies of effects of dietary factors, other than folic acid, on DNA methylation patterns in humans. In addition, the application of multiple different assays and investigations of different genomic loci makes it difficult to compare, or to combine, data across studies.
Whole-crop maize forage was ensiled without inoculant (control), inoculated with Lactobacillus buchneri and L. plantarum at a rate of 1 × 105 cfu/g fresh forage per bacterium (LBLP), or inoculated with Bacillus subtilis and L. plantarum at a rate 1 × 105 cfu/g fresh forage per bacterium (BSLP) with the goal to investigate the growth performance of finishing feedlot lambs. Thirty Dorper × Santa Ines lambs (29 ± 3.5 kg initial body weight) were used in the feedlot programme and assigned (n = 10) to one of three diets containing control, LBLP or BSLP silages in a 60:40 forage:concentrate ratio. Inoculation of maize silage did not alter dry matter intake (overall mean = 1.16 kg/day) and average daily gain (overall mean = 0.217 kg/day) of lambs. Consequently, feed efficiency remained unchanged. Inoculation of maize silage did not alter carcass and meat traits of lambs, with the exception of meat colour, wherein yellowness (b*) decreased by feeding LBLP and BSLP diets compared with the untreated diet. Regarding ruminal fermentation, there was an interaction between diets and the interval at which ruminal fluid was sampled for determining total volatile fatty acid concentration, but inoculation yielded no obvious results. In conclusion, the use of diets based on maize silage inoculated with L. plantarum combined with either L. buchneri or B. subtilis did not display relevant effects on growth performance of lambs; this response might be related to the limited impact of these bacterial inoculants on silage composition.
Understanding the peculiar properties of Ultra Diffuse Galaxies (UDGs) via spectroscopic analysis is a challenging task that is now becoming feasible. The advent of 10m-class telescopes and high sensitivity instruments is enabling the gathering of high quality spectra even for the faintest systems. In addition, advances in the modelling of stellar populations, stellar libraries, and full-spectral fitting codes are allowing the recovery of the stellar content shaping those spectra with unprecedented reliability. In this contribution we report on the extensive tests we have carried out using the inversion code STECKMAP. The similarities between the Star Formation Histories (SFH) recovered from STECKMAP (applied to high-quality spectra) and deep Colour-Magnitude diagrams fitting (resolved stars) in two Local Group dwarf galaxies (LMC and LeoA) are remarkable, demonstrating the impressive performance of STECKMAP. We exploit the capabilities of STECKMAP and perform one of the most complete and reliable characterisations of the stellar component of UDGs to date using deep spectroscopic data. We measure radial and rotation velocities, SFHs and mean population parameters, such as ages and metallicities, for a sample of five UDG candidates in the Coma cluster. From the radial velocities, we confirm the Coma membership of these galaxies. We find that their rotation properties, if detected at all, are compatible with dwarf-like galaxies. The SFHs of the UDG are dominated by old (∼ 7 Gyr), metal-poor ([M/H] ∼ -1.1) and alpha-enhanced ([Mg/Fe]∼ 0.4) populations followed by a smooth or episodic decline which halted ∼ 2 Gyr ago, possibly a sign of cluster-induced quenching. We find no obvious correlation between individual SFH shapes and any UDG morphological properties. The recovered stellar properties for UDGs are similar to those found for DDO 44, a local UDG analogue resolved into stars. We conclude that the UDGs in our sample are extended dwarfs whose properties are likely the outcome of both internal processes, such as bursty SFHs and/or high-spin haloes, as well as environmental effects within the Coma cluster.
The Pediatric Heart Network designed a career development award to train the next generation of clinician scientists in paediatric-cardiology-related research, a historically underfunded area. We sought to identify the strengths/weaknesses of the programme and describe the scholars’ academic achievements and the network’s return on investment.
Survey questions designed to evaluate the programme were sent to applicants – 13 funded and 19 unfunded applicants – and 20 mentors and/or principal investigators. Response distributions were calculated. χ2 tests of association assessed differences in ratings of the application/selection processes among funded scholars, unfunded applicants, and mentors/principal investigators. Scholars reported post-funding academic achievements.
Survey response rates were 88% for applicants and 100% for mentor/principal investigators. Clarity and fairness of the review were rated as “clear/fair” or “very clear/very fair” by 98% of respondents, but the responses varied among funded scholars, unfunded applicants, and mentors/principal investigators (clarity χ2=10.85, p=0.03; fairness χ2=16.97, p=0.002). Nearly half of the unfunded applicants rated feedback as “not useful” (47%). “Expanding their collaborative network” and “increasing publication potential” were the highest-rated benefits for scholars. Mentors/principal investigators found the programme “very” valuable for the scholars (100%) and the network (75%). The 13 scholars were first/senior authors for 97 abstracts and 109 manuscripts, served on 22 Pediatric Heart Network committees, and were awarded $9,673,660 in subsequent extramural funding for a return of ~$10 for every scholar dollar spent.
Overall, patient satisfaction with the Scholar Award was high and scholars met many academic markers of success. Despite this, programme challenges were identified and improvement strategies were developed.
Leishmaniasis is a complex of zoonotic diseases caused by parasites of the genus Leishmania, which can develop in domestic as well as wild animals and humans throughout the world. Currently, this disease is spreading in rural and urban areas of non-endemic regions in Brazil. Recently, bats have gained epidemiological significance in leishmaniasis due to its close relationship with human settlements. In this study, we investigated the presence of Leishmania spp. DNA in blood samples from 448 bats belonging to four families representing 20 species that were captured in the Triangulo Mineiro and Alto Paranaiba areas of Minas Gerais State (non-endemic areas for leishmaniasis), Brazil. Leishmania spp. DNA was detected in 8·0% of the blood samples, 41·6% of which were Leishmania infantum, 38·9% Leishmania amazonensis and 19·4% Leishmania braziliensis. No positive correlation was found between Leishmania spp. and bat food source. The species with more infection rates were the insectivorous bats Eumops perotis; 22·2% (4/18) of which tested positive for Leishmania DNA. The presence of Leishmania in the bat blood samples, as observed in this study, represents epidemiological importance due to the absence of Leishmaniasis cases in the region.
Pearl millet [Pennisetum glaucum (L.) R. Br.] is grown as a forage, cover and grain crop in Brazil. Historically, forage production has the most important use, but during the last 30 years, the use as a cover crop in no-till soybean [Glycine max (L.) Merrill] production systems has expanded greatly and is currently used on over 5 million ha. Grain production as livestock feed is presently of minor importance but expanding. This review cites 125 references and documents pearl millet research conducted in Brazil which is largely published in Portuguese. The review addresses recommended pearl millet production practices for different uses, including stand establishment, row spacing and plant population, fertiliser and pest management, and the use of pearl millet in rotation and as a cover crop between soybean or maize (Zea mays L.) production to reduce crop losses from nematode infestation. It is concluded that greater research investment in crop improvement, fertiliser and pest management, nematode management, and forage/grain utilisation is needed to fully take advantage of pearl millet to meet feed, food and soil improvement needs in Brazil. In addition, creation of a database on pearl millet production, marketing and utilisation to assist farmers and grain merchandisers, and increased extension programming on pearl millet production is needed.
Cover crops can offer erosion protection as well as soil and environmental quality benefits. Cereal rye (Secale cereale L.) is the most commonly used winter cover crop in corn–soybean rotations in the upper Midwest of the USA because of its superior winter hardiness and growth at cool temperatures. Cereal rye cover crops, however, can occasionally have negative impacts on the yield of a following corn crop, which discourages broader adoption and introduces substantial risk for corn farmers employing cover crops. We hypothesized that because cereal rye shares some pathogens with corn, it may be causing increased disease in corn seedlings planted soon after cereal rye termination. To test this, we performed a series of experiments in a controlled environment chamber to assess the response of corn seedlings with and without a commercial fungicide seed treatment to the presence of cereal rye or other species of cover crops that were terminated with herbicide prior to corn planting. Our results indicate that under cool and wet conditions, cereal rye reduces corn seedling growth performance and increases incidence of corn seedling root disease. Fungicide seed treatment had limited efficacy in preventing these effects, perhaps because environmental conditions were set to be very conducive for disease development. However, hairy vetch (Vicia villosa Roth) and winter canola (Brassica napus L.) cover crops had fewer negative impacts on corn seedlings compared with cereal rye. Thus, to expand the practice of cover cropping before corn, it should become a research priority to develop alternative management practices to reduce the risk of corn seedling root infection following cereal rye cover crops. Over the longer term, testing, selection and breeding efforts should identify potential cover crop species or genotypes that are able to match the winter hardiness, growth at cool temperatures and the conservation and environmental quality benefits of cereal rye, while avoiding the potential for negative impacts on corn seedlings when environmental conditions are suitable for disease development.
The aim of the present study was to explore and compare the association between a new vasoactive score – the Total Inotrope Exposure Score – and outcome and the established Vasoactive Inotrope Score in children undergoing cardiac surgery with cardiopulmonary bypass
The present study was a single-centre, retrospective study.
The study was carried out at a 21-bed cardiovascular ICU in a Tertiary Children’s Hospital between September, 2010 and May, 2011
The Total Inotrope Exposure Score is a new vasoactive score that brings together cumulative vasoactive drug exposure and incorporates dose adjustments over time. The performance of these scores – average, maximum Vasoactive Inotrope Score at 24 and 48 hours, and Total Inotrope Exposure Score – to predict primary clinical outcomes – either death, cardiopulmonary resuscitation, or extra-corporeal membrane oxygenation before hospital discharge – and secondary outcomes – length of invasive mechanical ventilation, length of ICU stay, and hospital stay – was calculated.
The study cohort included 167 children under 18 years of age, with 37 (22.2%) neonates and 65 (41.3%) infants aged between 1 month and 1 year. The Total Inotrope Exposure Score best predicted the primary outcome (six of 167 cases) with an unadjusted odds ratio for a poor outcome of 42 (4.8, 369.6). Although the area under curve was higher than other scores, this difference did not reach statistical significance. The Total Inotrope Exposure Score best predicted prolonged invasive mechanical ventilation, length of ICU stay, and hospital stay as compared with the other scores.
The Total Inotrope Exposure Score appears to have a good association with poor postoperative outcomes and warrants prospective validation across larger numbers of patients across institutions.
Previous studies have illustrated pediatric knowledge deficits among Emergency Medical Services (EMS) providers. The purpose of this study was to identify perspectives of a diverse group of EMS providers regarding pediatric prehospital care educational deficits and proposed methods of training improvements.
Purposive sampling was used to recruit EMS providers in diverse settings for study participation. Two separate focus groups of EMS providers (administrative and non-administrative personnel) were held in three locations (urban, suburban, and rural). A professional moderator facilitated focus group discussion using a guide developed by the study team. A grounded theory approach was used to analyze data.
Forty-two participants provided data. Four major themes were identified: (1) suboptimal previous pediatric training and training gaps in continuing pediatric education; (2) opportunities for improved interactions with emergency department (ED) staff, including case-based feedback on patient care; (3) barriers to optimal pediatric prehospital care; and (4) proposed pediatric training improvements.
Focus groups identified four themes surrounding preparation of EMS personnel for providing care to pediatric patients. These themes can guide future educational interventions for EMS to improve pediatric prehospital care.
BrownSA, HaydenTC, RandellKA, RappaportL, StevensonMD, KimIK. Improving Pediatric Education for Emergency Medical Services Providers: A Qualitative Study. Prehosp Disaster Med. 2017;32(1):20–26.
To characterise clusters of individuals based on adherence to dietary recommendations and to determine whether changes in Healthy Eating Index (HEI) scores in response to a personalised nutrition (PN) intervention varied between clusters.
Food4Me study participants were clustered according to whether their baseline dietary intakes met European dietary recommendations. Changes in HEI scores between baseline and month 6 were compared between clusters and stratified by whether individuals received generalised or PN advice.
Individuals in cluster 1 (C1) met all recommended intakes except for red meat, those in cluster 2 (C2) met two recommendations, and those in cluster 3 (C3) and cluster 4 (C4) met one recommendation each. C1 had higher intakes of white fish, beans and lentils and low-fat dairy products and lower percentage energy intake from SFA (P<0·05). C2 consumed less chips and pizza and fried foods than C3 and C4 (P<0·05). C1 were lighter, had lower BMI and waist circumference than C3 and were more physically active than C4 (P<0·05). More individuals in C4 were smokers and wanted to lose weight than in C1 (P<0·05). Individuals who received PN advice in C4 reported greater improvements in HEI compared with C3 and C1 (P<0·05).
The cluster where the fewest recommendations were met (C4) reported greater improvements in HEI following a 6-month trial of PN whereas there was no difference between clusters for those randomised to the Control, non-personalised dietary intervention.
The spiny rat (Proechimys guyannensis) is a neotropical rodent that is used in biomedical research, particularly research related to chronic resistance to epilepsy and infectious diseases. To our knowledge, there are few reports concerning the reproductive biology of this species. Therefore, besides providing basic biometric and morphometric data, in the present study we investigated testis function and spermatogenesis in adult spiny rats. The mean testis weight and gonadosomatic index obtained were 1.63 ± 0.2 g and 1.15 ± 0.1% respectively. Based on the development of the acrosomic system, 12 stages of the seminiferous epithelium cycle were characterized. Stages VI and VII presented the highest frequencies (~17–19%), whilst stages II to V showed the lowest frequencies (~2–4%). The most advanced germ cell types labelled at 1 h or 20 days after BrdU injections were respectively preleptotene/leptotene spermatocytes at stage VII and elongated spermatids at stage III. The mean duration of one cycle was 7.5 ± 0.01 days and the entire spermatogenic process lasted 33.7 ± 0.06 days (~4.5 cycles). The seminiferous tubules (ST) occupied ~96 ± 1% of the testis parenchyma, whereas Leydig cells comprised only 1.5 ± 0.4%. The number of Sertoli cells (SC) per testis gram and the SC efficiency (spermatids/SC) were respectively 78 × 106 ± 11 × 106 and 7.9 ± 1. The daily sperm production per testis gram (spermatogenic efficiency; daily sperm production (DSP)/g/testis) was 78 × 106 ± 8 × 106. To our knowledge, this spermatogenic efficiency is among the highest found for mammals investigated to date and is probably related to the very short duration of spermatogenesis and the very high ST percentage and SC number obtained for this species.
In this work we study the effect of satellite accretion on the building-up of the radial stellar age distribution in the discs of spiral galaxies. In addition, we analyse its effect on other chemical and dynamical properties of these systems up to their outskirts.
We propose a qualitative explanation for the light radial profile of a spiral galaxy based on the quantitative magnetic model of truncations (Battaner et al. 2002) in which when stars are born (hence the magnetic force acting on the progenitor gas cloud is no longer at work) migrate to larger orbits or escape.