• Premise of the study: Floral display describes the effect of flower size combined with the number of flowers per inflorescence. There is strong evidence that a floral-display trade-off operates ...under energetic constraint, with few-flowered inflorescences likely to have larger flowers than many-flowered inflorescences. Flower size can be estimated by different variables; thus, we propose that the variable for flower size that is most highly (negatively) correlated with the number of flowers per inflorescence will also be the best estimate of floral cost. Ranking the correlation with the phylogenetic signal of the variable can provide additional insight into the evolution of floral display. • Methods: The Myrtales were chosen as a model order based on age, worldwide distribution, and diversity of reproductive strategies. Ninety-nine species representing all families and one quarter of generic diversity across its geographic and ecological range were sampled to reconstruct a phylogeny based on rbcL and ndhF sequences. Correlation coefficients were calculated for flower size variables vs. the number of flowers per inflorescence. Phylogenetic signal was measured for all variables and for floral display. • Key results: Flowers per inflorescence showed significant negative correlation with the following flower size variables (weakest to strongest): filament length < anther size < flower depth < flower diameter. As the correlation of each character with number of flowers per inflorescence rose (suggesting increased cost), the values for phylogenetic signal diminished (suggesting less constraint). • Conclusions: We conclude that energetically costly floral characters appear to be less phylogenetically constrained, while lowcost floral characters maintain higher levels of phylogenetic inertia.
Climbers germinate on the ground but need external support to sustain their stems, which are maintained attached to supports through modified organs, that is, climbing mechanisms. Specialized ...climbing mechanisms have been linked to higher diversification rates. Also, different mechanisms may have different support diameter restrictions, which might influence climbers' spatial distribution. We test these assumptions by linking climbing mechanisms to the spatiotemporal diversification of neotropical climbers. A dataset of climbing mechanisms is presented for 9071 species. WCVP was used to standardize species names, map geographical distributions, and estimate diversification rates of lineages with different mechanisms. Twiners appear concentrated in the Dry Diagonal of South America and climbers with adhesive roots in the Chocó region and Central America. However, climbing mechanisms do not significantly influence the distribution of neotropical climbers. Also, we found no strong support for correlations between specialized climbing mechanisms and higher diversification rates. Climbing mechanisms do not strongly impact the spatiotemporal diversification of neotropical climbers on a macroevolutionary scale. We argue that the climbing habit is a synnovation, meaning the spatiotemporal diversification it promotes is due to the sum effect of all the habit's traits rather than isolated traits, such as climbing mechanisms.
The habit of eating specific meals has been addressed in several studies, but the evaluation of meal patterns has received less attention. This study aimed to describe the meal patterns of the ...Brazilian population. A complex sampling design was used to select the 46,164 ≥ 10-year-old individuals examined in the Brazilian National Dietary Survey. Food consumption was assessed by two non-consecutive 24-hour recalls applied throughout a one-week period. The exploratory data analysis approach was used to determine the meal patterns, i.e., how individuals combined the main meals (breakfast, lunch, dinner) and snacks (morning, afternoon, evening/night) throughout the day. The most common meal patterns were three main meals + one snack, reported by 25.1% of the individuals, and three main meals + two snacks (24.6%). Other meal patterns identified were: three main meals + three snacks (18.5%); three main meals and no snacks (10.9%); one or two main meals + two snacks (7.4%); one or two main meals + one snack (6.9%); one or two main meals + three snacks (4.2%); and one or two main meals and no snacks (2.3%). Meal patterns varied according to gender and age group, and on typical versus atypical food consumption days. We found that eight patterns characterized the daily meal consumption in Brazil. Furthermore, around 80% of the population had three main meals every day and about 13% did not report having any snacks. The characterization of meal habits is important for tailoring and targeting health promotion actions.
Cystic fibrosis (CF) is a genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator gene that leads to respiratory complications and mortality. Studies have shown ...shifts in the respiratory microbiota during disease progression in individuals with CF. In addition, CF patients experience short cycles of acute intermittent aggravations of symptoms called pulmonary exacerbations, which may be characterized by a decrease in lung function and weight loss. The resident microbiota become imbalanced, promoting biofilm formation, and reducing the effectiveness of therapy. The aim of this study was to monitor patients aged 8-23 years with CF to evaluate their lower respiratory microbiota using 16S rRNA sequencing. The most predominant pathogens observed in microbiota, Staphylococcus (Staph) and Pseudomonas (Pseud) were correlated with clinical variables, and the in vitro capacity of biofilm formation for these pathogens was tested. A group of 34 patients was followed up for 84 days, and 306 sputum samples were collected and sequenced. Clustering of microbiota by predominant pathogen showed that children with more Staph had reduced forced expiratory volume in one second (FEV.sub.1) and forced vital capacity (FVC) compared to children with Pseud. Furthermore, the patients' clinical condition was consistent with the results of pulmonary function. More patients with pulmonary exacerbation were observed in the Staph group than in the Pseud group, as confirmed by lower body mass index and pulmonary function. Additionally, prediction of bacterial functional profiles identified genes encoding key enzymes involved in virulence pathways in the Pseud group. Importantly, this study is the first Brazilian study to assess the lower respiratory microbiota in a significant group of young CF patients. In this sense, the data collected for this study on the microbiota of children in Brazil with CF provide a valuable contribution to the knowledge in the field.
This study was aimed at describing the snack consumption among Brazilian adolescents. The Brazilian National Dietary Survey (2017–2018) is a nationwide representative cross‐sectional study that ...collected food consumption data from 8264 adolescents (10 to 19 years old); data from one 24‐h recall were used, in which all foods and beverages consumed throughout the day prior to the interview were described along with the amount, unit of measurement, time, place and occasion of consumption (breakfast, lunch, dinner or snack). Snacks were classified as follows: (a) Morning snack: “Snacks” consumed between 6 AM and 12 PM; (b) Afternoon snack: “Snacks” consumed between 1 PM and 5 PM; (c) Evening snack: “Snacks” consumed between 6 PM and 5 AM. Individuals were categorised according to the number of “Snacks” per day (zero, one, two or three or more). Among the evaluated adolescents, 52.8% were female and 23.0% were overweight. The consumption of at least one snack per day was mentioned by 88.2% of the adolescents, with an average of 2.33 snacks per day. An afternoon snack was consumed by 70.0% of the adolescents. Snack consumption was related to higher mean daily energy intake and a greater contribution of carbohydrates, added sugar and trans fat to the total daily energy intake. ‘Cookies & Crackers’ and ‘Fast Foods’ were the groups that contributed the most to the energy intake provided by snacks, showing, therefore, that less healthy foods were relevant components of the snacks consumed. For their important contribution to food intake, snacking habits deserve attention among the topics covered in dietary guidelines.
This study aimed at assessing the association between psychosocial aspects and fruit and vegetable consumption in adolescents. Cross-sectional study developed with 327 adolescents from a public ...school in Brazil. A questionnaire developed for adolescents was applied to assess the influence of self-efficacy, family, peers, and body image on the consumption of fruits and vegetables. Specific questions assessed the intake frequency of fruits and vegetables, and the mean consumption was estimated using two 24-hour recalls. Scores related to psychosocial aspects were described as mean and median and the weight status was classified based on the body mass index. The average daily consumption of fruits and vegetables was 36.2 g and 45.4 g, respectively. Self-efficacy and the influence of peers were associated with an increase in the amount and frequency of fruits and vegetables consumption. Adolescents with higher scores of self-efficacy had greater average consumption of fruits and vegetables when compared to those with lower scores. The same was observed for the influence of peers. Self-efficacy and the influence of peers were the factors that most influenced the consumption of fruits and vegetables in adolescents.
Invasive candidiasis (IC) is a major cause of morbimortality in children. Previous studies described the clinical characteristics and risk factors for this infection; however, limited data are ...available on the predictors of mortality in these patients. In this context, we evaluated the risk factors associated with death due to IC in a pediatric tertiary care hospital in South of Brazil.
This is a retrospective, cross-sectional, observational, and analytical study of a series of pediatric patients with clinical and laboratory diagnosis of IC from March 2014 to September 2017. Univariate and multivariate analysis were performed to estimate the association between the characteristics of the patients and death.
A total of 94 cases of IC were included. The incidence was 1.13 cases per 1000 patients/d, with a mortality rate of 14%. There was a predominance of non-albicans Candida (71.3%) in IC cases and, although there is no species difference in mortality rates, biofilm formation was associated with increased mortality. Clinical characteristics such as male sex, stay in the intensive care unit, and thrombocytopenia; comorbidities such as cardiological disease and renal insufficiency; and risks such as mechanical ventilation and dialysis were associated with increased mortality.
Data from this study suggest that biofilm formation by Candida sp. is associated with increased mortality, and this is the first study to correlate the male sex and cardiological disease as risk factors for death in pediatric IC patients.
•Changes in floral traits across evolutionary time are expected in response to selective pressures imposed by pollinators.•Stamen dimetrism represents an important strategy to decrease pollen loss ...during bee-flower interactions in pollen flowers.•Stamen dimetrism is a labile trait, appeared several times throughout the Melastomataceae evolutionary history.•Our data suggest that plants that rely on pollinators to reproduce have evolved larger flowers with greater stamen dimetrism.•The dependence on pollinators for reproduction has probably contributed to the maintenance of the buzz pollination.
Changes in floral traits across evolutionary time are expected in response to selective pressures imposed by pollinators. Stamen dimetrism (here defined as size differences between stamens within the same flower) represents an important strategy to decrease pollen loss during bee-flower interactions in pollen flowers. However, the evolutionary history of stamen dimetrism, and the links between this and other reproductive traits across long periods of time are still poorly understood. Here we investigate the evolution of stamens dimetrism and the evolutionary correlation of this trait and other floral structures and reproductive strategies in Melastomataceae. Floral traits were scored from 336 species and reproductive biology data was gathered for 81 species. Stamen dimetrism is a labile trait, appeared several times throughout the evolutionary history of this clade and is evolutionarily correlated to floral size. Among the 81 species analyzed, we observed that the lineages that depend on pollinators to reproduce correspond to those that evolved the highest stamen dimetrism. The evolutionary lability of stamen dimetrism has probably contributed to the maintenance of the buzz pollination adaptive plateau in possibly the largest radiation of pollen flowers in angiosperms.
•Incongruence between morphological classification and molecular phylogenies is one of the biggest challenges to systematists.•Such incongruence might be explained by underlying homologies, namely ...parallelisms.•This study case shows how parallelisms and convergences are both related to taxonomic problems in systematic complex groups.•Parallelism may be a feature of recent diversified lineages, where the molecular basis for the expression of a character can still be trigged.•Re-expression of characters can make changes in early steps of development being less phylogenetically constraint than late stage ones.
The greatest challenge to the modern plant systematist is the interpretation of molecular phylogenies that do not correspond to previous classifications based on morphological data. Characters that on first appearance seem highly diagnostic are brought into focus by phylogeny and frequently shown to have evolved multiple times independently. Parallelism is usually neglected in such systematic studies and the homoplastic distribution of a character in a phylogeny is commonly accredited to convergent evolution. The impact of parallel evolution on angiosperm systematics is examined here using a taxonomically complex and species-rich group of tropical tree genera (Myrcia, Marlierea, Calyptranthes; Myrtaceae) as a case study. These groups are traditionally distinguished by flower characters and have been shown to be polyphyletic by molecular data. Floral ontogeny of distinct lineages is examined using SEM and plotted on a five gene phylogenetic hypothesis to estimate ancestral states and phylogenetic signal for developmental variation. Results show that floral characters responsible for taxonomic confusion are a result of both parallel evolution and convergence. This is contrasted with other diverse and taxonomically complex angiosperm groups and problematic taxonomy appears linked to recent diversification events where the same genetic basis remains latent, demonstrating parallelism to be an important factor in problematic taxonomies. In this study, variations in early stage floral development produce the most labile characters. This is discussed in light of ontogenetic patterns in angiosperms with focus on the evolutionary consequences of homoplastic variation during early vs late floral development. The prevalence of parallelism must be appreciated by taxonomists of complex groups. Future classifications of groups affected by parallelism are likely to require data from detailed, multi-disciplinary studies of key characters to interpret phylogenies correctly.
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