Evolutionary processes and its environmental correlates in the cranial morphology of western chipmunks (Tamias).

The importance of the environment in shaping phenotypic evolution lies at the core of evolutionary biology. Chipmunks of the genus Tamias (subgenus Neotamias) are part of a very recent radiation, occupying a wide range of environments with marked niche partitioning among species. One open question is if and how those differences in environments affected phenotypic evolution in this lineage. Herein we examine the relative importance of genetic drift versus natural selection in the origin of cranial diversity exhibited by clade members. We also explore the degree to which variation in potential selective agents (environmental variables) are correlated with the patterns of morphological variation presented. We found that genetic drift cannot explain morphological diversification in the group, thus supporting the potential role of natural selection as the predominant evolutionary force during Neotamias cranial diversification, although the strength of selection varied greatly among species. This morphological diversification, in turn, was correlated with environmental conditions, suggesting a possible causal relationship. These results underscore that extant Neotamias represent a radiation in which aspects of the environment might have acted as the selective force driving species' divergence

Contrasting patterns of RUNX2 repeat variations are associated with palate shape in phyllostomid bats and New World primates

Establishing the genetic basis that underlies craniofacial variability in natural populations is one of the main topics of evolutionary and developmental studies. One of the genes associated with mammal craniofacial variability is RUNX2, and in the present study we investigated the association between craniofacial length and width and RUNX2 across New World bats (Phyllostomidae) and primates (Catarrhini and Platyrrhini). Our results showed contrasting patterns of association between the glutamate/alanine ratios (Q/A ratio) and palate shape in these highly diverse groups. In phyllostomid bats, we found an association between shorter/broader faces and increase of the Q/A ratio. In New World monkeys (NWM) there was a positive correlation of increasing Q/A ratios to more elongated faces. Our findings reinforced the role of the Q/A ratio as a flexible genetic mechanism that would rapidly change the time of skull ossification throughout development. However, we propose a scenario in which the influence of this genetic adjustment system is indirect. The Q/A ratio would not lead to a specific phenotype, but throughout the history of a lineage, would act along with evolutionary constraints, as well as other genes, as a facilitator for adaptive morphological changes.Fil: Ferraz, Tiago. Universidade Federal do Rio Grande do Sul; Brasil. Universidade de Sao Paulo; BrasilFil: Rossoni, Daniela M.. Universidade de Sao Paulo; BrasilFil: Althoff, Sérgio L.. Universidade Regional de Blumenau; BrasilFil: Pissinatti, Alcides. Universidade Federal da Bahia; BrasilFil: Paixão Cortês, Vanessa R.. Centro de Primatologia do Rio de Janeiro; BrasilFil: Bortolini, María Cátira. Universidade Federal do Rio Grande do Sul; BrasilFil: González José, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Marroig, Gabriel. Universidade de Sao Paulo; BrasilFil: Salzano, Francisco M.. Universidade Federal do Rio Grande do Sul; BrasilFil: Gonçalves, Gislene L.. Universidad de Tarapacá de Arica; Chile. Universidade Federal do Rio Grande do Sul; BrasilFil: Hünemeier, Tábita. Universidade de Sao Paulo; Brasi

Baccharis trimera (Carqueja) Improves metabolic and redox status in an experimental model of type 1 diabetes.

Diabetes mellitus is a metabolic disorder that causes severe complications due to the increased oxidative stress induced by disease. Many plants are popularly used in the treatment of diabetes, e.g., Baccharis trimera (carqueja). The aim of this study was to explore the potential application of the B. trimera hydroethanolic extract in preventing redox stress induced by diabetes and its hypoglycemic properties. Experiments were conducted with 48 female rats, divided into 6 groups, named C (control), C600 (control + extract 600 mg/kg), C1200 (control + extract 1200 mg/kg), D (diabetic), D600 (diabetic + 600 mg/kg), and D1200 (diabetic + 1200 mg/kg). Type 1 diabetes was induced with alloxan, and the animals presented hyperglycemia and reduction in insulin and body weight. After seven days of experimentation, the nontreated diabetic group showed changes in biochemical parameters (urea, triacylglycerol, alanine aminotransferase, and aspartate aminotransferase) and increased carbonyl protein levels. Regarding the antioxidant enzymes, an increase in superoxide dismutase activity was observed but in comparison a decrease in catalase and glutathione peroxidase activity was noted which suggests that diabetic rats suffered redox stress. In addition, the mRNA of superoxide dismutase, catalase, and glutathione peroxidase enzymes were altered. Treatment of diabetic rats with B. trimera extract resulted in an improved glycemic profile and liver function, decreased oxidative damage, and altered the expression of mRNA of the antioxidants enzymes. These results together suggest that B. trimera hydroethanolic extract has a protective effect against diabetes

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

A multiple peak adaptive landscape based on feeding strategies and roosting ecology shaped the evolution of cranial covariance structure and morphological differentiation in phyllostomid bats

We explored the evolution of morphological integration in the most noteworthy example of adaptive radiation in mammals, the New World leaf-nosed bats, using a massive dataset and by combining phylogenetic comparative methods and quantitative genetic approaches. We demonstrated that the phenotypic covariance structure remained conserved on a broader phylogenetic scale but also showed a substantial divergence between interclade comparisons. Most of the phylogenetic structure in the integration space can be explained by splits at the beginning of the diversification of major clades. Our results provide evidence for a multiple peak adaptive landscape in the evolution of cranial covariance structure and morphological differentiation, based upon diet and roosting ecology. In this scenario, the successful radiation of phyllostomid bats was triggered by the diversification of dietary and roosting strategies, and the invasion of these new adaptive zones lead to changes in phenotypic covariance structure and average morphology. Our results suggest that intense natural selection preceded the invasion of these new adaptive zones and played a fundamental role in shaping cranial covariance structure and morphological differentiation in this hyperdiverse clade of mammals. Finally, our study demonstrates the power of combining comparative methods and quantitative genetic approaches when investigating the evolution of complex morphologies.Fil: Rossoni, Daniela M.. Bioscience Institute, Universidade de Sao Paulo; BrasilFil: Costa, Bárbara M. A.. Bioscience Institute, Universidade de Sao Paulo; BrasilFil: Giannini, Norberto Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Marroig, Gabriel. Bioscience Institute, Universidade de Sao Paulo; Brasi

Evolutionary processes and its environmental correlates in the cranial morphology of western chipmunks (Tamias).

The importance of the environment in shaping phenotypic evolution lies at the core of evolutionary biology. Chipmunks of the genus Tamias (subgenus Neotamias) are part of a very recent radiation, occupying a wide range of environments with marked niche partitioning among species. One open question is if and how those differences in environments affected phenotypic evolution in this lineage. Herein we examine the relative importance of genetic drift versus natural selection in the origin of cranial diversity exhibited by clade members. We also explore the degree to which variation in potential selective agents (environmental variables) are correlated with the patterns of morphological variation presented. We found that genetic drift cannot explain morphological diversification in the group, thus supporting the potential role of natural selection as the predominant evolutionary force during Neotamias cranial diversification, although the strength of selection varied greatly among species. This morphological diversification, in turn, was correlated with environmental conditions, suggesting a possible causal relationship. These results underscore that extant Neotamias represent a radiation in which aspects of the environment might have acted as the selective force driving species' divergence

Multiples lines of evidence unveil cryptic diversity in the <i>Lophostoma brasiliense</i> (Chiroptera: Phyllostomidae) complex

Phenotypically similar species – often called cryptic species – represent a challenge for taxonomy and conservation biology because they are usually undetectable to scientists. To unravel these cryptic taxa, studies now employ data from different sources under an integrative approach. We present an assessment of the cryptic diversity of the Lophostoma brasiliense species complex (Chiroptera: Phyllostomidae) based on multiple lines of evidence (molecular, morphological, morphometric, and geographic data) and using molecular (ABGD, ASAP, GMYC, and bPTP) and phenotypic (distance-based approaches and Normal Mixture Model Analyses) species delimitation methods. Our analyses recognized two distinct lineages with clear allopatric distributions. One lineage corresponds to Lophostoma brasiliense with a cis-Andean distribution and the other to the formerly species Lophostoma nicaraguae with a trans-Andean distribution. The two lineages probably diverged from a vicariant speciation driven by the uplift of the Andes less than six million years ago. Our work also shows that the wide range of environmental conditions during the recent history of South America may have promoted restrictions to gene flow among the populations of Lophostoma brasiliense. Finally, we raised L. nicaraguae to species level clarifying the species limit and morphological characteristics of lineages, and we provide an emended diagnosis and comparisons between the two taxa. We highlight the need for multiple lines of evidence to solve the remaining taxonomic problems among the remaining species complexes in Lophostoma.</p

Annato extract and ?-carotene modulate the production of reactive oxygen species/nitric oxide in neutrophils from diabetic rats.

Annatto has been identified asecarotenoids that havetantioxidative effects. It is well known that one of the key elements in the development of diabetic complications is oxidative stress. The immune system is especially vulnerable to oxidative damage because many immune cells, such as neutrophils, produce reactive oxygen species and reactive nitrogen species as part of the body?s defense mechanisms to destroy invading pathogens. Reactive oxygen species/reactive nitrogen species are excessively produced by active peripheral neutrophils, and may damage essential cellular components, which in turn can cause vascular complications in diabetes. The present study was undertaken to evaluate the possible protective effects of annatto on the reactive oxygen species and nitric oxide (NO) inhibition in neutrophils from alloxan-induced diabetic rats. Adult female rats were divided into six groups based on receiving either a standard diet with or without supplementation of annatto extract or beta carotene. All animals were sacrificed 30 days after treatment and the neutrophils were isolated using two gradients of different densities. The reactive oxygen species and NO were quantified by a chemiluminescence and spectrophotometric assays, respectively. Our results show that neutrophils from diabetic animals produce significantly more reactive oxygen species and NO than their respective controls and that supplementation with beta carotene and annatto is able to modulate the production of these species. Annatto extract may have therapeutic potential for modulation of the balance reactive oxygen species/NO induced by diabetes

Cyclic adenosine monophosphate protects renal cell lines against amphotericin B toxicity in a PKA-independent manner.

Amphotericin B is the ??gold standard?? agent in the management of serious systemic fungal infections. However, this drug can cause nephrotoxicity, which contributes up to 25% of all acute kidney injuries in critically ill patients. Cyclic adenosine monophosphate can protect kidney cells from death due to injury or drug exposure in some cases. Hence, the objective of this work was to evaluate if cAMP could prevent cell death that occurs in renal cell lines subjected to AmB treatment and, if so, to assess the involvement of PKA in the transduction of this signal. Two different renal cell lines (LLC-PK1 and MDCK) were used in this study. MTT and flow cytometry assays showed increased cell survival when cells were exposed to cAMP in a PKA-independent manner, which was confirmed by western blot. This finding suggests that cAMP (db-cAMP) may prevent cell death caused by exposure to AmB. This is the first time this effect has been identified when renal cells are exposed to AmB?s nephrotoxic potential

Alteration in cellular viability, pro-inflammatory cytokines and nitric oxide production in nephrotoxicity generation by Amphotericin B : involvement of PKA pathway signaling.

Amphotericin B is one of the most effective antifungal agents; however, its use is often limited owing to adverse effects, especially nephrotoxicity. The purpose of this study was to evaluate the effect of inhibiting the PKA signaling pathway in nephrotoxicity using Amphotericin B from the assessment of cell viability, pro-inflammatory cytokines and nitric oxide (NO) production in LLC-PK1 and MDCK cell lines. Amphotericin B proved to be cytotoxic for both cell lines, as assessed by the mitochondrial enzyme activity (MTT) assay; caused DNA fragmentation, determined by flow cytometry using the propidium iodide (PI) dye; and activated the PKA pathway (western blot assay). In MDCK cells, the inhibition of the PKA signaling pathway (using the H89 inhibitor) caused a significant reduction in DNA fragmentation. In both cells lines the production of interleukin-6 (IL)-6 proved to be a dependent PKA pathway, whereas tumor necrosis factor-alpha (TNF-?) was not influenced by the inhibition of the PKA pathway. The NO production was increased when cells were pre-incubated with H89 followed by Amphotericin B, and this production produced a dependent PKA pathway in LLC-PK1 and MDCK cells lines. Therefore, considering the present study?s results as a whole, it can be concluded that the inhibition of the PKA signaling pathway can aid in reducing the degree of nephrotoxicity caused by Amphotericin B