Comparative transcriptome analysis reveals lineage- and environment-specific adaptations in cacti from the Brazilian Atlantic Forest.

MAIN CONCLUSION: Natural selection influenced adaptive divergence between Cereus fernambucensis and Cereus insularis, revealing key genes governing abiotic stress responses and supporting neoteny in C. insularis. Uncovering the molecular mechanisms driving adaptive divergence in traits related to habitat adaptation remains a central challenge. In this study, we focused on the cactus clade, which includes Cereus sericifer F.Ritter, Cereus fernambucensis Lem., and Cereus insularis Hemsley. These allopatric species inhabit distinct relatively drier regions within the Brazilian Atlantic Forest, each facing unique abiotic conditions. We leveraged whole transcriptome data and abiotic variables datasets to explore lineage-specific and environment-specific adaptations in these species. Employing comparative phylogenetic methods, we identified genes under positive selection (PSG) and examined their association with non-synonymous genetic variants and abiotic attributes through a PhyloGWAS approach. Our analysis unveiled signatures of selection in all studied lineages, with C. fernambucensis northern populations and C. insularis showing the most PSGs. These PSGs predominantly govern abiotic stress regulation, encompassing heat tolerance, UV stress response, and soil salinity adaptation. Our exclusive observation of gene expression tied to early developmental stages in C. insularis supports the hypothesis of neoteny in this species. We also identified genes associated with abiotic variables in independent lineages, suggesting their role as environmental filters on genetic diversity. Overall, our findings suggest that natural selection played a pivotal role in the geographic range of these species in response to environmental and biogeographic transitions.

A historical stepping-stone path for an island-colonizing cactus across a submerged "bridge" archipelago.

Here we use population genomic data (ddRAD-Seq) and ecological niche modeling to test biogeographic hypotheses for the divergence of the island-endemic cactus species Cereus insularis Hemsl. (Cereeae; Cactaceae) from its sister species C. fernambucensis Lem. The Cereus insularis grows in the Fernando de Noronha Islands (FNI), a Neotropical archipelago located 350 km off the Brazilian Atlantic Forest (BAF) coast. Phylogeographic reconstructions support a northward expansion by the common ancestor of C. insularis and C. fernambucensis along the mainland BAF coast, with C. insularis diverging from the widespread mainland taxon C. fernambucensis after colonizing FNI in the late Pleistocene. The morphologically distinct C. insularis is monophyletic and nested within C. fernambucensis, as expected from a progenitor-derivative speciation model. We tested alternative biogeographic and demographic hypotheses for the colonization of the FNI using Approximate Bayesian Computation. We found the greatest support for a stepping-stone path that emerged during periods of decreased sea level (the "bridge" hypothesis), in congruence with historical ecological niche modeling that shows highly suitable habitats on stepping-stone islands during glacial periods. The outlier analyses reveal signatures of selection in C. insularis, suggesting a putative role of adaptation driving rapid anagenic differentiation of this species in FNI.

Unravelling phylogenetic relationships of the tribe Cereeae using target enrichment sequencing.

BACKGROUND AND AIMS: Cactaceae are succulent plants, quasi-endemic to the American continent, and one of the most endangered plant groups in the world. Molecular phylogenies have been key to unravelling phylogenetic relationships among major cactus groups, previously hampered by high levels of morphological convergence. Phylogenetic studies using plastid markers have not provided adequate resolution for determining generic relationships within cactus groups. This is the case for the tribe Cereeae s.l., a highly diverse group from tropical America. Here we aimed to reconstruct a well-resolved phylogenetic tree of tribe Cereeae and update the circumscription of suprageneric and generic groups in this tribe. METHODS: We integrated sequence data from public gene and genomic databases with new target sequences (generated using the customized Cactaceae591 probe set) across representatives of this tribe, with a denser taxon sampling of the subtribe Cereinae. We inferred concatenated and coalescent phylogenetic trees and compared the performance of both approaches. KEY RESULTS: Six well-supported suprageneric clades were identified using different datasets. However, only genomic datasets, especially the Cactaceae591, were able to resolve the contentious relationships within the subtribe Cereinae. CONCLUSIONS: We propose a new taxonomic classification within Cereeae based on well-resolved clades, including new subtribes (Aylosterinae subtr. nov., Uebelmanniinae subtr. nov. and Gymnocalyciinae subtr. nov.) and revised subtribes (Trichocereinae, Rebutiinae and Cereinae). We emphasize the importance of using genomic datasets allied with coalescent inference to investigate evolutionary patterns within the tribe Cereeae.

Leishmania (L.) amazonensis LaLRR17 increases parasite entry in macrophage by a mechanism dependent on GRP78.

Leishmaniases affect 12 million people worldwide. They are caused by Leishmania spp., protozoan parasites transmitted to mammals by female phlebotomine flies. During the life cycle, promastigote forms of the parasite live in the gut of infected sandflies and convert into amastigotes inside the vertebrate macrophages. The parasite evades macrophage's microbicidal responses due to virulence factors that affect parasite phagocytosis, survival and/or proliferation. The interaction between Leishmania and macrophage molecules is essential to phagocytosis and parasite survival. Proteins containing leucine-rich repeats (LRRs) are common in several organisms, and these motifs are usually involved in protein­protein interactions. We have identified the LRR17 gene, which encodes a protein with 6 LRR domains, in the genomes of several Leishmania species. We show here that promastigotes of Leishmania (L.) amazonensis overexpressing LaLRR17 are more infective in vitro. We produced recombinant LaLRR17 protein and identified macrophage 78 kDa glucose-regulated protein (GRP78) as a ligand for LaLRR17 employing affinity chromatography followed by mass spectrometry. We showed that GRP78 binds to LaLRR17 and that its blocking precludes the increase of infection conferred by LaLRR17. Our results are the first to report LRR17 gene and protein, and we hope they stimulate further studies on how this protein increases phagocytosis of Leishmania.

Quality of podcasts recorded by nursing lecturers as pre-class learning material for students: An observational study.

AIM: To evaluate the quality of podcasts produced by lecturers as pre-class learning material; to verify lecturers' buy-in, after a specific workshop, regarding the practice of producing and using podcasts. BACKGROUND: The teaching-learning process has undergone significant changes in recent years with the proposal of the flipped classroom strategy, which places the student at the center of the learning process and uses technology that requires adaptation of lecturers, both inside and outside the classroom. Pre-class learning material is one of the features of the flipped classroom model. It provides basic concepts for problem solving in small group discussion in classroom. Podcasts for this educational purpose are a recent technology and their innovative characteristics require deeper understanding in terms of their influence and usability. DESIGN: Prospective, descriptive and quantitative study. SETTING AND POPULATION: A workshop on the production of educational podcasts was offered to 23 lecturers on the Nursing course. METHODS: Data were collected in the second semester of 2021 and the quality analysis was based on criteria available in the literature. RESULTS: Eighteen professors (78 %) participated in the study and 46 podcasts were produced. Most professors being nurses (61 %), followed by biologists (28 %). Most have a doctorate degree (72 %). These podcasts were available for a mean of five days before the classes and their mean access rate by students was 58 %. There was no correlation between the access rate and the period of availability before the relative class. Most podcasts were informative (100 %) and monologues (98 %). The average duration was 6.2 min, which is within the ideal duration recommended in the literature. All of the podcasts included a description of the learning objectives at the beginning and most of them also included a closing message at the end. CONCLUSION: The nursing lecturers were able to produce their podcasts, which met quality criteria and reached the standards suggested by experts in the field.

Revisiting phylogeny, systematics, and biogeography of a Pleistocene radiation.

PREMISE: Pilosocereus (Cactaceae) is an important dry forest element in all subregions and transitional zones of the neotropics, with the highest diversity in eastern Brazil. The genus is subdivided into informal taxonomic groups; however, most of these are not supported by recent molecular phylogenetic inferences. This lack of confidence is probably due to the use of an insufficient number of loci and the complexity of cactus diversification. Here, we explored the species relationships in Pilosocereus in more detail, integrating multilocus phylogenetic approaches with the assessment of the ancestral range and the effect of geography on diversification shifts. METHODS: We used 28 nuclear, plastid, and mitochondrial loci from 54 plant samples of 31 Pilosocereus species for phylogenetic analyses. We used concatenated and coalescent phylogenetic trees and Bayesian models to estimate the most likely ancestral range and diversification shifts. RESULTS: All Pilosocereus species were clustered in the same branch, except P. bohlei. The phylogenetic relationships were more associated with the geographic distribution than taxonomic affinities among taxa. The genus began diversifying during the Plio-Pleistocene transition in the Caatinga domain and experienced an increased diversification rate during the Calabrian age. CONCLUSIONS: We recovered a well-supported multispecies coalescent phylogeny. Our results refine the pattern of rapid diversification of Pilosocereus species across neotropical drylands during the Pleistocene and highlight the need for taxonomic rearrangements in the genus. We recovered a pulse of diversification during the Pleistocene that was likely driven by multiple dispersal and vicariance events within and among the Caatinga, Cerrado, and Atlantic Forest domains.

Análise de complicações de lipoenxertias realizadas em hospital público universitário entre 2015 e 2018: estudo retrospectivo transversal / Analysis of complications from fat grafting performed at a public university hospital between 2015 and 2018: a cross-sectional retrospective study

Introdução: A lipoenxertia consiste no processo de coleta de gordura de uma área doadora de gordura por meio de lipoaspiração seguida da realocação desse tecido em área receptora por meio de seringas e cânulas. É um processo seguro utilizado em cirurgias estéticas e reconstrutivas, de acordo com a literatura. O objetivo é avaliar as taxas de complicações dos procedimentos de lipoenxertia realizados em um hospital público universitário no período de 2015 a 2018, em comparação com dados previamente relatados na literatura. Métodos: Estudo observacional retrospectivo desenvolvido em hospital universitário público de Campinas - SP a partir da revisão de prontuários de pacientes submetidos a lipoenxertia nesta instituição de 2015 a 2018. Resultados: Em relação às complicações, a grande maioria correspondeu à reabsorção de gordura (62%). O hematoma correspondeu ao segundo mais comum (38% dos casos), seguido do edema (19%). Dor e discromia vieram em seguida, com 10% e 7% dos casos, respectivamente. Apenas um caso de infecção de ferida operatória foi descrito. Outras complicações menos frequentes foram hiperemia (5%), assimetrias (5%), descamação (2%), parestesia local (3%) e lesão cutânea (2%). Nenhuma outra complicação maior foi relatada, como embolia gordurosa ou complicações cirúrgicas graves como sangramento, sepse, anafilaxia, entre outras. Conclusão: Os procedimentos de lipoaspiração para coleta de gordura e lipoenxertia mostraram-se seguros e com baixo índice de complicações na amostra estudada, concordando com dados da literatura.

Introduction: Fat grafting consists of collecting fat from one fat donor area via liposuction, then reallocating this tissue into a receptor area through syringes and cannulas. According to the literature, it is a safe process used in aesthetic and reconstructive surgeries. The objective is to evaluate complication rates of fat grafting procedures performed in a public university hospital from 2015 to 2018 in comparison with data previously reported in the literature. Methods: A retrospective observational study developed at a public university hospital in Campinas-SP based on the revision of medical records of patients who underwent the fat grafting procedure in this institution from 2015 to 2018. Results: Regarding the complications, the vast majority corresponded to fat reabsorption (62%). Bruise corresponded to the second most common (38% of cases), followed by edema (19%). Pain and dyschromia followed next, with 10% and 7% of cases, respectively. Only one case of operative wound infection was described. Other less frequent complications included hyperemia (5%), asymmetries (5%), desquamation (2%), local paraesthesia (3%) and skin lesion (2%). No other larger complication was reported, such as fat embolism or severe surgical complications such as bleeding, sepsis, or anaphylaxis. Conclusion: The procedures of liposuction for fat collection and fat grafting were proved to be safe, yielding low complication rates in the studied sample, which agrees with data reported in the literature.

Perfil epidemiológico dos pacientes submetidos à cirurgia para tratamento de fratura de face em um hospital universitário / Epidemiological profile of patients undergoing surgery to treat facial fractures in a university hospital

Introdução: Trauma facial apresenta relevância estética, social e econômica. Conhecer sua epidemiologia permite formular medidas de prevenção, educação e sistematização de atendimento. Métodos: Triagem, através do sistema de informação hospitalar, buscando pacientes que necessitaram de cirurgia para fratura de face entre abril de 2015 e abril de 2020. Foram, então, coletados dados epidemiológicos. Resultados: Foram selecionados 141 pacientes. A média de idade foi 34 anos, com maioria do sexo masculino (85%). A etiologia predominante foi acidente com veículo automotor e a fratura cirúrgica mais prevalente foi a de órbita (67%). A mediana de tempo entre o trauma e a cirurgia foi de 18 dias. Sessenta pacientes apresentaram lesões associadas à fratura de face, com destaque para as ortopédicas e neurológicas. Conclusão: A etiologia mais comum de fraturas faciais cirúrgicas foi acidente de trânsito, sendo o sexo masculino mais afetado. As fraturas de órbita foram as mais tratadas cirurgicamente.

Introduction: Facial trauma presents aesthetic, social and economic relevance. Knowing its epidemiology makes it possible to formulate measures for prevention, education and systematization of care. Methods: Research through the hospital information system, looking for patients who needed to undergo surgery for face fracture between April 2015 and April 2020. Epidemiological data were then collected. Results: 141 patients were selected. The average age was 34 years, with most males (85%). The predominant etiology was motor vehicle accidents, and the most prevalent surgical fracture was orbit (67%). The median time between trauma and surgery was 18 days. Sixty patients had injuries associated with facial fractures, especially orthopedic and neurological injuries. Conclusion: The most common etiology of surgical facial fractures was a traffic accident, predominantly among men. Orbit fractures were the most surgically treated.

A target Capture Probe Set Useful for Deep- and Shallow-Level Phylogenetic Studies in Cactaceae.

The molecular phylogenies of Cactaceae have enabled us to better understand their systematics, biogeography, and diversification ages. However, most of the phylogenetic relationships within Cactaceae major groups remain unclear, largely due to the lack of an appropriate set of molecular markers to resolve its contentious relationships. Here, we explored the genome and transcriptome assemblies available for Cactaceae and identified putative orthologous regions shared among lineages of the subfamily Cactoideae. Then we developed a probe set, named Cactaceae591, targeting both coding and noncoding nuclear regions for representatives from the subfamilies Pereskioideae, Opuntioideae, and Cactoideae. We also sampled inter- and intraspecific variation to evaluate the potential of this panel to be used in phylogeographic studies. We retrieved on average of 547 orthologous regions per sample. Targeting noncoding nuclear regions showed to be crucial to resolving inter- and intraspecific relationships. Cactaceae591 covers 13 orthologous genes shared with the Angiosperms353 kit and two plastid regions largely used in Cactaceae studies, enabling the phylogenies generated by our panel to be integrated with angiosperm and Cactaceae phylogenies, using these sequences. We highlighted the importance of using coalescent-based species tree approaches on the Cactaceae591 dataset to infer accurate phylogenetic trees in the presence of extensive incomplete lineage sorting in this family.

Evolutionary Genetics of Cacti: Research Biases, Advances and Prospects.

Here, we present a review of the studies of evolutionary genetics (phylogenetics, population genetics, and phylogeography) using genetic data as well as genome scale assemblies in Cactaceae (Caryophyllales, Angiosperms), a major lineage of succulent plants with astonishing diversity on the American continent. To this end, we performed a literature survey (1992-2021) to obtain detailed information regarding key aspects of studies investigating cactus evolution. Specifically, we summarize the advances in the following aspects: molecular markers, species delimitation, phylogenetics, hybridization, biogeography, and genome assemblies. In brief, we observed substantial growth in the studies conducted with molecular markers in the past two decades. However, we found biases in taxonomic/geographic sampling and the use of traditional markers and statistical approaches. We discuss some methodological and social challenges for engaging the cactus community in genomic research. We also stressed the importance of integrative approaches, coalescent methods, and international collaboration to advance the understanding of cactus evolution.

Coalescent-based species delimitation meets deep learning: Insights from a highly fragmented cactus system.

Delimiting species boundaries is a major goal in evolutionary biology. An increasing volume of literature has focused on the challenges of investigating cryptic diversity within complex evolutionary scenarios of speciation, including gene flow and demographic fluctuations. New methods based on model selection, such as approximate Bayesian computation, approximate likelihoods, and machine learning are promising tools arising in this field. Here, we introduce a framework for species delimitation using the multispecies coalescent model coupled with a deep learning algorithm based on convolutional neural networks (CNNs). We compared this strategy with a similar ABC approach. We applied both methods to test species boundary hypotheses based on current and previous taxonomic delimitations as well as genetic data (sequences from 41 loci) in Pilosocereus aurisetus, a cactus species complex with a sky-island distribution and taxonomic uncertainty. To validate our method, we also applied the same strategy on data from widely accepted species from the genus Drosophila. The results show that our CNN approach has a high capacity to distinguish among the simulated species delimitation scenarios, with higher accuracy than ABC. For the cactus data set, a splitter hypothesis without gene flow showed the highest probability in both CNN and ABC approaches, a result agreeing with previous taxonomic classifications and in line with the sky-island distribution and low dispersal of P. aurisetus. Our results highlight the cryptic diversity within the P. aurisetus complex and show that CNNs are a promising approach for distinguishing complex evolutionary histories, even outperforming the accuracy of other model-based approaches such as ABC.

[Historical construction of the concept of the enzyme and approaches in biology textbooks]. / A construção histórica do conceito de enzima e sua abordagem em livros didáticos de biologia.

The use of the history and philosophy of science in teaching and learning is commonly neglected, linear, and/or out of context in textbooks. This article investigates whether this also occurs with the concept of enzymes. A brief review of the literature establishes the theoretical foundation to investigate how the concept of enzymes is presented in nine textbooks, following three different lines of analysis. A general lack of interconnection was seen in biochemistry topics, with enzymes usually only presented via the "lock-and-key" model, which does not best represent their complexity. Furthermore, conceptual limitations resulting from a lack of historical contextualization (partial or complete) were also observed.

O uso de história e filosofia da ciência no ensino-aprendizagem é comumente negligenciado, linear e/ou descontextualizado nos livros didáticos. Isso aconteceria com a história do conceito de enzimas? Este trabalho busca investigar essa questão. Para a fundamentação teórica, foi realizada breve revisão bibliográfica, investigando-se como o conceito de enzimas é apresentado em nove livros didáticos, seguindo três categorias de análise. Encontrou-se, de forma geral, falta de interconexão nos assuntos de bioquímica, sendo as enzimas usualmente apresentadas apenas pelo modelo "chave-fechadura", que hoje não é representativo da complexidade do fenômeno. Além disso, foram observados limites conceituais decorrentes da ausência ou deficiência na contextualização histórica presente no material didático.

A construção histórica do conceito de enzima e sua abordagem em livros didáticos de biologia / Historical construction of the concept of the enzyme and approaches in biology textbooks

Resumo O uso de história e filosofia da ciência no ensino-aprendizagem é comumente negligenciado, linear e/ou descontextualizado nos livros didáticos. Isso aconteceria com a história do conceito de enzimas? Este trabalho busca investigar essa questão. Para a fundamentação teórica, foi realizada breve revisão bibliográfica, investigando-se como o conceito de enzimas é apresentado em nove livros didáticos, seguindo três categorias de análise. Encontrou-se, de forma geral, falta de interconexão nos assuntos de bioquímica, sendo as enzimas usualmente apresentadas apenas pelo modelo "chave-fechadura", que hoje não é representativo da complexidade do fenômeno. Além disso, foram observados limites conceituais decorrentes da ausência ou deficiência na contextualização histórica presente no material didático.

Abstract The use of the history and philosophy of science in teaching and learning is commonly neglected, linear, and/or out of context in textbooks. This article investigates whether this also occurs with the concept of enzymes. A brief review of the literature establishes the theoretical foundation to investigate how the concept of enzymes is presented in nine textbooks, following three different lines of analysis. A general lack of interconnection was seen in biochemistry topics, with enzymes usually only presented via the "lock-and-key" model, which does not best represent their complexity. Furthermore, conceptual limitations resulting from a lack of historical contextualization (partial or complete) were also observed.

The genome of a thorny species: comparative genomic analysis among South and North American Cactaceae.

MAIN CONCLUSION: The first South American cactus nuclear genome assembly associated with comparative genomic analyses provides insights into nuclear and plastid genomic features, such as size, transposable elements, and metabolic processes related to cactus development. Here, we assembled the partial genome, plastome, and transcriptome of Cereus fernambucensis (Cereeae, Cactaceae), a representative species of the South American core Cactoideae. We accessed other genomes and transcriptomes available for cactus species to compare the heterozygosity level, genome size, transposable elements, orthologous genes, and plastome structure. These estimates were obtained from the literature or using the same pipeline adopted for C. fermabucensis. In addition to the C. fernambucensis plastome, we also performed de novo plastome assembly of Pachycereus pringlei, Stenocereus thurberi, and Pereskia humboldtii based on the sequences available in public databases. We estimated a genome size of ~ 1.58 Gb for C. fernambucensis, the largest genome among the compared species. The genome heterozygosity was 0.88% in C. fernambucensis but ranged from 0.36 (Carnegiea gigantea) to 17.4% (Lophocereus schottii) in the other taxa. The genome lengths of the studied cacti are constituted by a high amount of transposable elements, ranging from ~ 57 to ~ 67%. Putative satellite DNAs are present in all species, excepting C. gigantea. The plastome of C. fernambucensis was ~ 104 kb, showing events of translocation, inversion, and gene loss. We observed a low number of shared unique orthologs, which may suggest gene duplication events and the simultaneous expression of paralogous genes. We recovered 37 genes that have undergone positive selection along the Cereus branch that are associated with different metabolic processes, such as improving photosynthesis during drought stress and nutrient absorption, which may be related to the adaptation to xeric areas of the Neotropics.

The influence of dietary Motore™ supplement on antioxidant status to Aeromonas hydrophila infection in Rhamdia quelen.

This study points to evaluate the effects of pre-treatment with standardized dry extract of Curcuma longa (Motore™) added to the diet (0; 250; 500; and 750 mg/kg) on oxidative stress parameters, longevity, and therapeutic success in Rhamdia quelen experimentally infected with Aeromonas hydrophila (MF 372510). After treatment, the liver and kidney were collected to determine non-enzymatic oxidative parameters such as the formation of thiobarbituric acid reactive substances (TBARS), non-protein thiols (NPSH), and quantification of reactive oxygen species (ROS) levels. Also, two enzymatic antioxidant parameters were evaluated: superoxide dismutase (SOD) and catalase (CAT) activities. The results showed an increase of ROS and TBARS levels, a depletion in NPSH, and a decrease of SOD and CAT activities in infected fish compared to control. The highest Motore™ dose minimized the deleterious effect of A. hydrophila infection improving longevity, oxidative status, and survival rate. The addition of 750 mg Motore™/kg feed is recommended for silver catfish in fish farming. Serious economic losses in Rhamdia quelen culture caused by Aeromonas hydrophila infections can be prevented by the addition of Motore™ to the diet.

The potential of genome-wide RAD sequences for resolving rapid radiations: a case study in Cactaceae.

The reconstruction of relationships within recently radiated groups is challenging even when massive amounts of sequencing data are available. The use of restriction site-associated DNA sequencing (RAD-Seq) to this end is promising. Here, we assessed the performance of RAD-Seq to infer the species-level phylogeny of the rapidly radiating genus Cereus (Cactaceae). To examine how the amount of genomic data affects resolution in this group, we used datasets and implemented different analyses. We sampled 52 individuals of Cereus, representing 18 of the 25 species currently recognized, plus members of the closely allied genera Cipocereus and Praecereus, and other 11 Cactaceae genera as outgroups. Three scenarios of permissiveness to missing data were carried out in iPyRAD, assembling datasets with 30% (333 loci), 45% (1440 loci), and 70% (6141 loci) of missing data. For each dataset, Maximum Likelihood (ML) trees were generated using two supermatrices, i.e., only SNPs and SNPs plus invariant sites. Accuracy and resolution were improved when the dataset with the highest number of loci was used (6141 loci), despite the high percentage of missing data included (70%). Coalescent trees estimated using SVDQuartets and ASTRAL are similar to those obtained by the ML reconstructions. Overall, we reconstruct a well-supported phylogeny of Cereus, which is resolved as monophyletic and composed of four main clades with high support in their internal relationships. Our findings also provide insights into the impact of missing data for phylogeny reconstruction using RAD loci.

Dermal Sinus Tract associated with Type I and Type II Split Cord Malformation.

The dermal sinus tract of the spine is associated with other occult spinal dysraphisms, such as the split cord malformation (diastematomyelia) in a 40% of the cases and embryologically is not clearly defined if the dermal sinus and split cord malformation have origin in gastrulation or late primary neurulation, but the most accepted theory of the dermal sinus tract consists in early incomplete disjunction, which explains the relation with other spinal dysraphisms. Here, we present two cases, with a dermal sinus tract of the spine associated with Type I and Type II split cord malformation.

Dinâmica da recuperação ambiental de pilhas de estéril em mineração de calcário por regeneração natural / Environmental recovery dynamics of waste dumps in calcary mining by natural regeneration

RESUMO A presente pesquisa teve como objetivo avaliar a dinâmica da recuperação ambiental de pilhas de estéril de mineração de calcário por meio da análise da composição e estrutura fitossociológica da regeneração natural. O estudo foi conduzido em um empreendimento minerário localizado em Salto de Pirapora (SP), Brasil, com pilhas de estéril abandonadas desde 1994 e 2013, e um fragmento florestal nativo, totalizando três tratamentos. Em cada área, foram alocadas 12 parcelas de 10 × 10 m, onde todos os indivíduos arbustivo-arbóreos com altura acima de 1,30 m foram amostrados, identificados e avaliados quanto à composição e à estrutura fitossociológica. Foi constatada a ocorrência da regeneração natural nas pilhas de estéril com o aumento de indivíduos e espécies ao longo do tempo. Os resultados indicam que a vegetação presente nessas pilhas está em transição de floresta pioneira para um estágio sucessional mais avançado. Contudo, a Leucaena leucocephala estabeleceu-se mais expressivamente que as demais, inibindo o desenvolvimento de outras espécies. Por fim, sugerem-se ações de manejo para que a sucessão ecológica das pilhas de estéril não seja comprometida.

ABSTRACT The present research had as objective to evaluate the dynamics of the environmental recovery of waste dumps in calcary mining by analyzing the composition and phytosociological structure of natural regeneration. The study was carried out in a waste dumo located in Salto de Pirapora, São Paulo, Brazil, with sterile piles abandoned since 1994 and 2013 and a native forest fragment, totaling three treatments. Twelve plots of 10 × 10 m were allocated to each area, where all shrub-tree individuals with height above 1.30 m were sampled, identified and evaluated for their composition and phytosociological structure. The occurrence of natural regeneration in the sterile cells was observed with the increased number of individuals and species over time. The results indicate that the vegetation present in the waste dumps is in transition from pioneer forest to a more advanced successional stage. However, Leucaena leucocephala has established itself more expressively than other species, inhibiting the development of other species. Finally, management actions are suggested so that the ecological succession of the waste dumps is not compromised.

Maintaining genetic integrity with high promiscuity: Frequent hybridization with low introgression in multiple hybrid zones of Melocactus (Cactaceae).

Hybridization and introgression between species in contact/hybrid zones provide important insight into the genetic and ecological mechanisms of speciation. Cactaceae represents the most important radiation of true succulent angiosperms in the New World. This diversification continues to date, with species experiencing few intrinsic barriers to gene flow and the frequent occurrence of natural hybridization. Here, we used RAD-Seq single-nucleotide polymorphism (SNP) data to investigate the genetic architecture of hybridization in four hybrid zones hosting Melocactus concinnus and four congeneric species (M. ernestii, M. glaucescens, M. paucispinus, and M. zehntneri). Our results revealed that M. concinnus is highly promiscuous in sympatric areas and hybridizes with various species distributed in Morro do Chapéu (Diamantina Plateau, Bahia), eastern Brazil. However, the contemporary genomic introgression among the investigated species is very low (c. 2-5%), confirming that even in the face of hybridization, Melocactus species maintain their genetic integrity. The genomic cline approach showed a large fraction of loci deviating from a model of neutral introgression, where most of the loci are consistent with selection favoring parental genotypes. Our results suggest the occurrence of weak premating but strong postmating reproductive isolation in the analyzed cactus species. Furthermore, as most of the Melocactus species are restricted in distribution, hybridization might negatively affect their integrity if hybrids replace the parental species.

Recalcitrant carbon and nitrogen in agriculture soi ls with residue accumulation and fertilization under tropical conditions / Carbono recalcitrante e nitrogênio em solos com acumulação e fertilização de resíduos em condições tropicais

Soil organic matter has a strong relation to total organic carbon, and about 85% of organic carbon consists of humic substances (HS), classified as humin (HU), humic (HA) and fulvic acids (FA), and denominated as recalcitrant carbon in soil. HS are formed by complex, heterogeneous and polydisperse molecules, which have significant influence on the soil physical and chemical characteristics. The study evaluates the hypothesis that agricultural soils treated with organic residues may present higher carbon stocks as presented in forest soils. The aim of this study was to evaluate alterations in recalcitrant carbon and nitrogen stocks in Oxisol (Forest - FL, unfertilized Brachiaria - UB, and fertilized Brachiaria - FB) and Cambisol (Forest - FC, Coastcross - CC, sugarcane - CA, and silage corn - SM) at surface (0.0 - 0.1) and subsurface (0.1 - 0.2 m), in the Zona da Mata in Minas Gerais state, Brazil. Result shows that fertilization, low soil disturbance and residual removal promoted increase of C and N content in HS, being close to native forests. Both, carbon and nitrogen recalcitrant, presented reduction with soil depth. HU ranged from 10.5 to 16.7 g kg-1 and presented the highest concentration compared to FA and HA. In Oxisol, FL and FB presented the highest SH concentration and demonstrate the positive effect of fertilization on carbon stocks improving soil quality in well-managed and productive areas. While, In Cambisol, FC and CC presented higher carbon and nitrogen in HS, mainly for HU and HA fractions, and SM showed the lowest concentrations in all fractions. Our results suggest that soil managements with lower soil disturbance and residual removal promotes increasing of carbon and nitrogen in recalcitrant fraction, with concentration close to native forests. Pasture should be fertilized to improve recalcitrant carbon and nitrogen stocks, avoiding process of degradation in tropical soil. It is an important outcome due to high levels of degraded areas in Brazil caused by inadequate use of soil mainly with pasture.

A matéria orgânica do solo tem uma forte relação com o carbono orgânico total, cerca de 85% do carbono orgânico é composto por substâncias húmicas (HS), classificadas como humina (HU), ácidos húmicos (HA) e fúlvicos (FA), denominadas como carbono recalcitrante no solo. As HS são formadas por moléculas complexas, heterogêneas e polidispersas, que exercem influência significativa nas características físicas e químicas do solo. O estudo avalia a hipótese de que solos agrícolas tratados com resíduos orgânicos podem apresentar maiores estoques de carbono como os encontrados em solos florestais. O objetivo destetrabalho foi avaliar as alterações nos estoques de carbono e nitrogênio recalcitrantes em Latossolo (Floresta - FL, Brachiaria não fertilizada ­ UB, e Brachiaria fertilizada - FB) e Cambissolo (Floresta - FC, coastcross - CC, cana-de-açúcar e milho para silagem - SM) na superfície (0,0 - 0,1) e sub-superfície (0,1 - 0,2 m), na Zona da Mata em Minas Gerais, Brasil. Os resultados mostram que a adubação, a baixa perturbação do solo e a remoção dos resíduos promoveram aumento do teor de C e N na HS, estando próximos às florestas nativas. Ambos, carbono e nitrogênio recalcitrantes, apresentaram redução com a profundidade do solo. A HU variou de 10,5 a 16,7 g kg-1 e apresentou a maior concentração em relação à FA e HA. Em Latossolo, FL e FB apresentaram a maior concentração de SH e demonstraram o efeito positivo da adubação nos estoques de carbono, melhorando a qualidade do solo em áreas bem manejadas e produtivas. Enquanto, no Cambissolo, FC e CC apresentarammaiores teores de carbono e nitrogênio nas HS, principalmente nas frações HU e HA, e SM apresentou as menores concentrações em todas as frações. Nossos resultados mostram que manejos de solo com menor perturbação e remoção de resíduos promovem o aumento de carbono e nitrogênio em frações recalcitrantes, com concentração próxima às florestas nativas. A pastagem deve ser fertilizada para melhorar o estoque de carbono e nitrogênio recalcitrante, evitando o processo de degradação do solo tropical. Este é um resultado importante devido aos altos níveis de áreas degradadas no Brasil causadas pelo uso inadequado do solo,principalmente com pastagens.