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Brazil's Atlantic Ocean coast is approximately 7500 km long, with several coastal and oceanic islands. The cyanoflora of this area is not commonly included in published studies, resulting in an underestimated diversity. Here, we isolated and analysed through a polyphasic approach three strains of marine benthic homocyted cyanobacteria from Brazilian coastal islands with two distinct climates: ALCB 132761 and ALCB 132774 are from the tropics, and ALCB 132760 from the subtropics. These strains presented differences in their cell morphometry and presence/absence of sheath, but were similar in apical cell shape, colour, and form of the trichome. In the 16S rRNA phylogeny, Maximum likelihood (ML) and Bayesian posterior probability (PP) analyses placed our strains in two robust clades. We propose that Microlinema tropicalium gen. et sp. nov. (ALCB 132774) is placed in the Leptolyngbyaceae, and Insularia amadoi gen. et sp. nov. (ALCB 132761) and Salileptolyngbya insularis sp. nov. (ALCB 132760) in Pseudanabaenaceae. The 16S-23S Internal Transcribed Spacer (ITS) was used to reconstruct Box B and D1-D1' secondary structures, which were treated as autapomorphic characters. The new thin homocyted benthic cyanobacterial taxa described here from marine coastal islands of Brazil help to disentangle the Leptolyngbyaceae and Pseudanabaenaceae. •Polyphasic description of two new Brazilian genera Insularia and Microlinema. •Expansion of Salileptolyngbya: recognition of one species for the Atlantic Ocean. •Elucidation of benthic genera in the Leptolyngbyaceae and Pseudanabaenaceae. [ABSTRACT FROM AUTHOR]

• The venation pattern is of high diagnostic value in recognizing the species studied. • Both species exhibit adaptive xeromorphic characteristics in the Chaco Biome. • Both in Chaco, one more mesophytic, the other more xerophytic. Aspidosperma is one of the most representative genera in Apocynaceae in Brazil, composed of trees or small trees popularly known as perobas. The genus is distributed throughout tropical America, from Mexico to Argentina, with the exception of Chile. It comprises 80 species, 42 of which occur in Brazil, which is the center of diversity for the genus. Aspidosperma triternatum and Aspidosperma quebracho-blanco , name the Aspidosperma sect. Pungentia , section is easily distinguished from the others, even in the vegetative state, by grouping species that have leaves with pungent apexes, unique in the genus. However, A. triternatum and A. quebracho-blanco are difficult to distinguish due to the morphological similarities they present, such as the pungent apex of their whorled leaves and the yellowish white color of their flowers. Therefore, our objective was to develop a study to obtain leaf morphological using the usual methods of microscopy. The most important diagnostic characters useful for delimiting the species were: the number of pairs of secondary veins; the patterns of distance between these and the median and distal region, as well as the reticulation of these veins; the branching of the tertiary veins; the impression of the quaternary veins as well as their development and the shape of the areola; shape of epidermal cells; cuticular ornamentation pattern; types and distribution of trichomes; distribution of stomata; organization and number of cell layers in mesophyll. We have shown from the performed study that the species have remarkable morphological and anatomical differences which made possible a better circumscription of the group. [ABSTRACT FROM AUTHOR]

Sporotrichosis is a neglected endemic mycosis with a high incidence in Latin America, mainly in Brazil. Sporothrix schenckii is the most frequent species in Latin America, whereas Sporothrix brasiliensis is the predominant species observed in Brazil and is associated with both human and animal sporotrichosis. Sporotrichosis treatment remains restricted to a few options, itraconazole being the first choice for human and animal therapy. In this work, we screened the molecular library Pathogen Box (Medicines for Malaria Venture [MMV], Switzerland) in search of compounds with anti-Sporothrix activity. Our initial screen of the 400 compounds identified five compounds that inhibited more than 80% of S. brasiliensis and S. schenkii growth. Among those, three compounds (MMV675968, MMV102872, and MMV002817 (known as iodoquinol)) not previously described as antifungals or agrochemicals, were selected for further evaluation. MMV102872 and iodoquinol showed the most promising combination of antifungal activity (lower inhibitory concentration) and fungal selectivity (lower cytotoxicity in LLC-MK2 cells). Scanning electron microscopy and flow cytometry analyses revealed that MMV102872 and iodoquinol induced changes in cell morphology, membrane integrity, and the presence of neutral lipids, impairing fungal survival. Our results indicate that MMV102872 and iodoquinol are promising molecules for use as scaffolds for the development of new antifungal agents. [ABSTRACT FROM AUTHOR]

Background: Wild capuchin monkeys (Sapajus libidinosus) usually are found in conserved forests near the zoo and the urban areas of Brasília city, Brazil. In this study, some capuchin monkeys were captured using traps, followed by safe biological procedures for their overall health analysis, based on specific haematological and biochemical tests of blood samples. Methods: Blood was collected from a total of 17 monkeys for the determination of parameters, namely packed cell volume (PCV), leucocytes, erythrocytes, platelets and triglycerides. Statistical analyses for average values, median, standard deviation and range were performed. Results: These parameters were set based on the minimum and maximum values obtained from the blood tests. Data are presented in tabulated form. Conclusions: Capture procedures were based on animal safety analysis for free‐living animals and would help future studies on wild animals. The collected samples used in this study suggested the animals to be apparently healthy in their habitat. [ABSTRACT FROM AUTHOR]

Background: More than 3 years since the last Zika virus (ZIKV) outbreak in Brazil, researchers are still deciphering the molecular mechanisms of neurovirulence and vertical transmission, as well as the best way to control spread of ZIKV, a flavivirus. The use of pesticides was the main strategy of mosquito control during the last ZIKV outbreak. Methods: We used vesicular stomatitis virus (VSV) tagged with green fluorescent protein (GFP) as our prototypical virus to study the impact of insecticide pyriproxyfen (PPF). VZV-GFP infected and uninfected Jurkat, HeLa and trophoblast cells were treated with PPF and compared to untreated cells (control). Cell viability was determined by the MTT assay. Cell morphology, presence of extracellular vesicles (EVs), virus infection/GFP expression as well as active mitochondrial levels/localization were examined by confocal microscopy. Results: PPF, which was used to control mosquito populations in Brazil prior to the ZIKV outbreak, enhances VSV replication and has cell membrane-altering properties in the presence of virus. PPF causes enhanced viral replication and formation of large EVs, loaded with virus as well as mitochondria. Treatment of trophoblasts or HeLa cells with increasing concentrations of PPF does not alter cell viability, however, it proportionately increases Jurkat cell viability. Increasing concentrations of PPF followed by VSV infection does not interfere with HeLa cell viability. Both Jurkats and trophoblasts show proportionately increased cell death with increased concentrations of PPF in the presence of virus. Conclusions: We hypothesize that PPF disrupts the lipid microenvironment of mammalian cells, thereby interfering with pathways of viral replication. PPF lowers viability of trophoblasts and Jurkats in the presence of VSV, implying that the combination renders immune system impairment in infected individuals as well as enhanced vulnerability of fetuses towards viral vertical transmission. We hypothesize that similar viruses such as ZIKV may be vertically transmitted via EV-to-cell contact when exposed to PPF, thereby bypassing immune detection. The impact of pesticides on viral replication must be fully investigated before large scale use in future outbreaks of mosquito borne viruses. [ABSTRACT FROM AUTHOR]

The green alga Micrasterias arcuata is commonly found in the periphyton of slightly acidic ponds and wet grasslands of central Brazil. We used M. arcuata complex as a model system for evaluation of the following questions: (a) Is there any relation between morphological characteristics of M. arcuata populations and ecological features of the sites? (b) Can the observed plasticity be explained by an allometric scaling relationship leading to differential distribution of the morphotypes among different habitats (ponds and wet grasslands)? (c) Is there any surface-to-volume ratio (S:V) scaling that can be explained as adaptive response to ecological characteristics of sites? A total of 50 individual semicells of M. arcuata were photographed from ten natural populations, yielding a 500 objects dataset. Individuals from ponds were morphologically different from the ones in the wet grasslands, presenting bigger cells, but also with higher S:V. The eventual surface loss usually associated to bigger sizes was compensated by more elaborated cells, yielding positive allometry of the S:V ratio scaling. Our data support the idea that such differences in cell morphology are an adaptation to environmental conditions, especially desiccation stress favoring cells with lower S:V and higher isoperimetric quotient in the wet grasslands. [ABSTRACT FROM AUTHOR]

In the last decade ostrich farms spread throughout the world as an alternative source of investment. Although previous studies have reported hematology and biochemical values for ostriches from several regions of the world, little information is available regarding leukocyte morphology. This study reports the morphology and ultrastructure of ostrich leukocytes and hematology and biochemical values from birds raised in Brazil. Heterophils presented a lobulated nucleus, and fusiform, and acidophilic and peroxidase-negative granules. Ultrastructurally, 2 kinds of cytoplasmic granules were observed: one was large and fusiform and the other smaller with heterogeneous morphology and electrondensity; granules were peroxidase-negative. Eosinophils had a kidney-shaped eccentrically placed nucleus that was rarely lobulated and eosinophilic, round, and peroxidase-positive granules. At the ultrastructure level, 2 main kinds of granules with the same size and form but different electron density were seen; granules were peroxidase-positive. Lymphocytes and thrombocytes had the same characteristics of other avian species; monocytes presented morphological heterogeneity. Hematological and serum biochemical profiles had no sex influence and were established for ostriches raised in southeastern Brazil. These parameters will help the diagnosis of specific ostrich pathologies and serve as basic knowledge for studies in immunology and comparative avian pathology. [ABSTRACT FROM AUTHOR]

• The chemical composition and structure of the layers of the external coat and the three-dimensional organization of the gel during the swelling process are reported here for seeds of Magonia pubescens. • Histochemical-light and scanning electron microscopy (SEM) were used in conjunction with CP-MAS (cross polarization--magic angle spinning: solid state) &sup13;C NMR spectroscopy to analyse the seed coat layers. • M. pubescens seeds extrude a gel from the second of five regions of the external seed coat when immersed in water. This gel, visualized by SEM, had an extruded cylindrical, laminated structure. Staining revealed two anionic components in the cells of the second layer; the cytoplasm showed the presence of carbohydrates containing vicinal hydroxyl groups and at least some of these carbohydrates were acidic polysaccharides. Part of the β-linked glucan present in this layer was cellulosic material. Phenolic compounds were not detected in the second layer, but existed in other layers. Lignin and/or tannins were shown in the cell walls of the three innermost layers by CP-MAS &sup13;C NMR spectroscopy. • The solid-state NMR technique had the advantage of being more sensitive and quantitative compared with light microscropy and might prove to be a useful tool in investigating cell components. [ABSTRACT FROM AUTHOR]

• The study describes Alexandrium fragae , a new harmful species closely related to A. minutum. • The presence of reticulation only on the hypotheca is the main morphological feature in A. fragae which diferentiate it from A. minutum. • The new species produces GTX2&3 and STX. The genus Alexandrium comprises some of the most potentially toxic marine algae. A new toxic species of Alexandrium, A. fragae sp. nov., was found in Guanabara Bay, Rio de Janeiro, southern Brazil. The new species produces GTX2&3 and STX. The cell morphology of A. fragae resembles A. minutum in many characters, including the small size; the rounded-elliptical shape; and the shapes of the apical pore complex (APC), first apical plate (1′), sixth precingular plate (6″), and anterior and posterior sulcal plates (s.a. and s.p.). The main diagnostic characters of A. fragae are the ornamentation pattern, smooth epitheca and reticulated hypotheca, all of which were present in both natural populations and cultures. Phylogenies inferred from the ITS, LSU, and SSU rDNA of A. fragae showed that A. fragae clustered in a well-supported clade, distinct from other Alexandrium species. Morphology and molecular analyses based on ITS and LSU rDNA indicated that A. fragae strains and Alexandrium sp. from Japan (D163C5, D164C6) are a single species. Our findings suggest that the Alexandrium morphotype with a smooth epitheca and reticulated hypotheca, previously identified as A. minutum in different geographic regions, may corresponds to A. fragae. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the cytocompatibility and mineralization potential of two premixed hydraulic endodontic sealers compared with an epoxy resin-based root canal sealer. The cellular responses and mineralization capacity were studied in human periodontal ligament stem cells (hPDLSCs) that were exposed to premixed hydraulic sealers, Bio-C Sealer (Angelus, Londrína, PR, Brazil), TotalFill BC Sealer (FKG Dentaire SA, La-Chaux-de-fonds, Switzerland) and an epoxy resin-based material, AH Plus (Dentsply De Trey, Konstanz, Germany). Non-exposed cultures served as the control. The endodontic sealers were assessed using scanning electron microscopy (SEM) and energy dispersive X-ray microanalysis (EDX). Statistical analyses were done using Analisis of Variance (ANOVA), with Bonferroni adjusted pairwise comparison (p = 0.05). AH Plus reduced cell viability and cell migration, whereas increased cell viability and cell migration were observed in the Bio-C Sealer and the TotalFill BC Sealer (p < 0.05). The lowest cell attachment and spreading were observed for all concentrations of AH Plus, whereas the highest were observed for TotalFill BC Sealer. At the end of 21 days, only the Bio-C Sealer and the TotalFill BC Sealer supported matrix mineralization (p < 0.05). Additionally, SEM-EDX revealed high content of calcium, oxygen, and silicon in the Bio-C Sealer and the TotalFill BC Sealer. Based on the results from this study, Bio-C Sealer and TotalFill BC Sealer demonstrated better cytocompatibility in terms of cell viability, migration, cell morphology, cell attachment, and mineralization capacity than AH Plus. [ABSTRACT FROM AUTHOR]