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Background and aims – Brazil has more than 40 species of Vanilla. Some taxa have been considered to be obscure since they are known only from the type specimen. This is the case of some south-eastern Brazilian species such as V. dubia and V. dungsii. While studying the diversity of Brazilian Vanilla, plants of an unidentified species were found in Ubatuba, São Paulo, Brazil. After flowering, it was confirmed that the species corresponded to the obscure V. dubia. Material and methods – A redescription of V. dubia is provided and a morphological comparison with the related taxa V. dungsii and V. paulista is presented. An illustration of V. dubia is provided, and its geographic distribution is presented. The identity of the enigmatic V. dungsii is also clarified based on holotype examination and on images of living specimens. Key results – Vanilla dubia is recognized by its coriaceous leaves with prominent vascular bundles in transverse section, by its white 3-lobed labellum with yellow lobes and undulate-crenulate margins, and by its tuberculate appendages on the apical portion of the labellar crest. Morphological characteristics suggest a close relationship of V. dubia with V. dungsii and V. paulista. Vanilla dubia occurs in the Dense Ombrophilous Forest, while V. paulista occurs in the Semi-deciduous Mesophytic Forest, and V. dungsii is endemic to the Dense Montane Ombrophilous Forest. Based on current data, V. dubia is assessed as Endangered. Conclusion – Evaluation of vegetative and reproductive characters from living and herbaria specimens is crucial to understanding the identity and species boundaries of Vanilla. The data presented here show that the species occurring in the Atlantic Forest, V. dubia and V. dungsii, are more closely related to each other than to V. paulista, which occurs in Semi-deciduous Mesophytic Forests. A proposal to change the status of V. dungsii as a subspecies of V. dubia can be further considered.

Background and aims – With 40 species, Brazil is the centre of diversity for Vanilla. Frederico Carlos Hoehne described eight Vanilla species for the Brazilian flora, including Vanilla schwackeana, an obscure taxon currently assumed to be a synonym of V. planifolia. While studying Neotropical Vanilla, plants were found in gallery forests of the Vale do Rio Doce region, Minas Gerais, south-eastern Brazil. Based on the examination of the protologues of the Brazilian species, in addition to the study of herbarium specimens, it was verified that the plants correspond to the rare V. schwackeana. Material and methods – A redescription of V. schwackeana is provided, and a morphological comparison with other Neotropical taxa is presented. An illustration of V. schwackeana based on living specimens is provided, and its geographic distribution is presented based on recent findings. The position of V. schwackeana within Vanilla is discussed based on both morphological data and a molecular phylogeny. Key results – Vanilla schwackeana is distinguishable by its pseudopetiolate leaves, by its largely elliptic to obelliptic leaf blades with attenuate base and acuminate apex, by its apical racemes with small flowers, by its yellow labellum with white undulate-crenulate margins, and by its papillous appendages on the apical portion of the labellar crest. Both morphological and molecular data suggest a close relationship of V. schwackeana with V. appendiculata, V. hartii, and the Brazilian endemic V. rupicola. Based on current data, V. schwackeana is assessed as Critically Endangered. Conclusion – Integrative taxonomy was crucial to understand the identity and species boundaries of V. schwackeana. The V. appendiculata/V. schwackeana/(V. hartii/V. rupicola) clade comprises an unrecognized infrageneric Vanilla group. It seems plausible that the formation of a new infrageneric group will be necessary. As the habitat of V. schwackeana has been devastated by iron ore extraction, conservation strategies for this Brazilian endemic species will be necessary.

This study focuses on the synthesis of silver nanoparticles (AgNPs) at different high concentrations and investigates their physicochemical properties, antimicrobial activity, and cytotoxicity. AgNPs were synthesized using the alcohol reduction process, involving the reduction of AgNO3 and its subsequent stabilization via PVP at 80 °C for 4 h. The AgNO3/PVP molar ratio and the average molecular weight were modified in this study. Characterization analyses revealed that the synthesized AgNPs exhibited characteristic surface plasmon resonance absorption peaks at approximately 415 nm, as observed in the UV–Vis spectrum. The results presented in X-ray diffractograms confirmed the face-centered cubic structure of metallic Ag in the nanoparticles. The nanoparticles demonstrated uniform size and shape, with controllable dimensions ranging from 3 to 800 nm. Regarding antimicrobial activity, the MIC solutions exhibited higher potency against the planktonic cells of Candida albicans. The determination of inhibition halos indicated that the silver nanoparticles had an impact on the microorganisms Streptococcus mutans, Candida albicans, and Actinomyces israelii. Furthermore, lower-concentration compositions showed reduced cytotoxic effects compared to higher-concentration particles. Based on the findings, it was concluded that the AgNO3/PVP molar ratio plays a crucial role in the production of AgNPs. These synthesized nanoparticles exhibit desirable physicochemical properties and demonstrate potential antimicrobial activity and controlled cytotoxicity.

Despite numerous efforts over the last three decades, nucleic acid-based therapeutics still lack delivery platforms in the clinical stage. Cell-penetrating peptides (CPPs) may offer solutions as potential delivery vectors. We have previously shown that designing a “kinked” structure in the peptide backbone resulted in a CPP with efficient in vitro transfection properties. Further optimization of the charge distribution in the C-terminal part of the peptide led to potent in vivo activity with the resultant CPP NickFect55 (NF55). Currently, the impact of the linker amino acid was further investigated in the CPP NF55, with the aim to discover potential transfection reagents for in vivo application. Taking into account the expression of the delivered reporter in the lung tissue of mice, and the cell transfection in the human lung adenocarcinoma cell line, the new peptides NF55-Dap and NF55-Dab* have a high potential for delivering nucleic acid-based therapeutics to treat lung associated diseases, such as adenocarcinoma.

Several studies have reported stingless Meliponini bees gathering hairs from the labella of Maxillaria spp., including M. ochroleuca, a member of the M. splendens alliance. Such hairs usually contain food materials and are thought to have nutritional value. The papillose labella of representatives of the Maxillaria splendens alliance, however, bear scattered, simple 1-5-celled uniseriate trichomes (hairs) that lack food materials. By contrast, here, as well as polyphenolic compounds, typical labellar papillae usually contain small quantities of starch, protein, and minute droplets of lipid, the last probably involved in the production of fragrance. Towards the labellum apex occur elevated groups of papillae that lack food materials, but contain volatile compounds, probably fragrance precursors. In the past, the terms ‘trichomes’ or ‘hairs’ and ‘papillae’ have been used interchangeably, causing some confusion. Since the trichomes, however, unlike the papillae, are easily detachable and can fragment, it is most likely they, not the papillae, that have previously been observed being collected by bees, but their poor food content indicates that they do not function as food-hairs. Even so, our field observations of M. ochroleuca reveal that stingless bees scrape polyphenol-rich labellar tissue and possibly use this material to produce a resinous, complex, heterogeneous substance commonly referred to as ‘bee glue’, used for nest construction and repair.

In this paper, I seek to clarify, criticize, and expand upon the ambiguous-yet-influential concept of divine violence introduced by Walter Benjamin’s “Zur Kritik der Gewalt”. I proceed in three parts: in the first, I outline Benjamin’s argument about the cycle of mythical violence and divine violence’s special role as an interruption of that cycle. Next, I explicate Spinoza’s key concepts of potentia and potestas, which can be used to more clearly define what ought to instead be translated as “divine force”. In the third part, through Benjamin’s brief discussion of Sorel’s theory of the anarchist general strike, I equate potentia as a determinate power of aggregative individuals to divine force, both as a collective action and as an idea itself. I use this renewed and more sophisticated concept of divine force to oppose several interpretations of Benjamin’s concept, including Benjamin’s own quietist stance toward divine force.

Abstract Background In several Apicomplexa, the formation of moving junctions (MJs) at the interface between the external membranes of the invading parasite and the host cell is essential for the process of parasite invasion. In Plasmodium falciparum and Toxoplasma gondii, the MJ is composed of the Apical Membrane Antigen 1 (AMA1) and Rhoptry Neck Proteins (RONs) complex; specifically, AMA1 interacts with RON2 during host cell invasion. Methods Recombinant proteins based on Plasmodium vivax RON2 (A2033-P2100) and its synthetic peptide fragments, one cyclic and one linear, based on PvRON2 (D2035-T2074) were generated and used to evaluate the interaction with P. vivax AMA1 (PvAMA1) by the far western blot, surface plasmon resonance (SPR), and isothermal titration microcalorimetry (ITC) methods. The structural studies of peptides were performed by circular dichroism, and the structural analysis of the complex of PvAMA1 with peptides based on PvRON2 (D2035-T2074) was conducted with small-angle X-ray scattering (SAXS). Results Surface plasmon resonance (KD = 23.91 ± 2.078 μmol/L) and ITC (K = 3 × 105 mol/L) studies conclusively showed an interaction between the cyclic peptide based on PvRON2 and PvAMA1-His6. In contrast, the linear peptide and recombinant PvRON2 (GST fusion protein) did not show an interaction with PvAMA1. However, the interaction among recombinant proteins PvRON2.2 and PvAMA1-His6 was possible to show by far western blot. Conclusions The results show that the PvRON2 structure, particularly the S–S bond between C2051 and C2063, is determinant for the existence of the interaction between PvAMA1 and PvRON2.

Environmental pollution is a major cause of disease and death. Exposures in early life are especially dangerous. Patterns of exposure vary greatly across countries. In low-income and lower middle income countries (LMICs), infectious, maternal, neonatal, and nutritional diseases are still major contributors to disease burden. By contrast, in upper middle income and high-income countries noncommunicable diseases predominate. To examine patterns of environmental exposure and disease and to relate these patterns to levels of income and development, we obtained publically available data in 12 countries at different levels of development through a global network of World Health Organization Collaborating Centres in Children's Environmental Health. Pollution exposures in early life contribute to both patterns. Chemical and pesticide pollution are increasing, especially in LMICs. Hazardous wastes, including electronic waste, are accumulating. Pollution-related chronic diseases are becoming epidemic. Future Global Burden of Disease estimates must pay increased attention to the short- and long-term consequences of environmental pollution.

Epidendrum, the largest genus of Neotropical orchids, contains both nectar-secreting and nectarless species. Here, we compare the fine structure of the inner floral spur, termed the cuniculus, in nectariferous (E. difforme, E. nocturnum,E. porpax, E. rigidum, E. vesicatum) and seemingly nectarless (E. capricornu, E. ciliare, E. criniferum, E. pseudepidendrum, E. radicans, E. xanthoianthinum) species. This is the first time for such a detailed investigation of cuniculus structure to be undertaken for Epidendrum. Our aim was to characterize features indicative of secretory activity and to ascertain whether flowers presumed to be nectarless produce alternative pollinator food-rewards. The cuniculus is formed by fusion of the basal part of the labellum and column and extends alongside the ovary and transmitting tract. Our study indicates that all investigated species produce nectar or nectar-like secretion to varying degrees, and no alternative pollinator food-rewards were observed. Even though macroscopic investigation of presumed rewardless species failed to reveal the presence of secretion within the cuniculus, close observations of the cells lining the cuniculus by LM, SEM, and TEM revealed the presence of cuticular blisters and surface material. Moreover, the similarity of both the thick tangential cell walls (with the exception of E. vesicatum) and organelle complement of cuniculus epidermal cells in both copiously nectariferous species and those producing only small quantities of surface secretion confirmed the presence of secretory activity in species generally regarded to be rewardless. The secretory character was particularly obvious in the cells of the cuniculus of E. nocturnum, but also in E. ciliare, E. radicans and E. xanthoianthinum, since electron-dense cytoplasm and mitochondria, ER and secretory vesicles were abundant. Furthermore, cell wall protuberances occurred in E. nocturnum, which was indicative of intense transmembrane transport. This investigation highlights the need to examine more closely whether Epidendrum spp. considered to lack food-rewards based solely on macroscopic examination really are rewardless and deceptive.

Sepsis is a disease that affects a wide variety of individuals, including the young, the elderly, and those admitted to the hospital with diverse acute or chronic conditions. Because sepsis is such a heterogeneous disease, some researchers believe that personalized medicine may represent a promising means of improving the prognosis for certain patients. Of those who develop sepsis, diabetic patients remain a significant proportion, because diabetes is a metabolic disorder that is associated with disturbances in the immune system, which facilitates bacterial infections. Fatty acid–binding proteins (FABPs) are a family of transport proteins with an important role in metabolism; therefore, we decided to measure their levels in diabetic rats, as part of a search for a novel biomarker of sepsis. Diabetes was experimentally induced in male Wistar rats, some of which then underwent cecal ligation and puncture, and the levels of FABP4 and FABP7 were measured in their serum and key tissues. Serum FABP7 levels in diabetic septic rats were significantly higher than those in non-diabetic septic rats. Consequently, we propose that FABP7 should be further investigated as a potential biomarker of sepsis in diabetic patients.

Environmental problems related to the generation of wastewater contaminated with organic compounds and the emissions of pollutants from fuel burning have become major global problems. Thus, there is a need for the development of alternative and economically viable technologies for the remediation of the affected ecosystems. Therefore, this work describes the preparation and characterization of a Ti(OH)4 catalyst with the modified surface for application in the photodegradation of organic compounds (methylene blue (MB) dye and the drug amiloride (AML)) and in the artificial photosynthesis process. Characterization results reveal that peroxo groups on the surface of the catalyst had a great influence on the optical properties of the Ti(OH)4 and consequently in its photocatalytic property. This catalyst showed a high photocatalytic activity for the degradation of organic pollutants under visible radiation, reaching approximately 98% removal of both the dye and the drug in 150 min of reaction. In addition, the catalyst presented a great potential for the reduction of CO2 under ultraviolet (UV) radiation when compared to P25, which is a classic catalyst used in photocatalytic processes. The highest photocatalytic activity can be attributed to the strong visible light absorption, due to the narrow band gap, and the effective separation of photogenerated electron-hole pairs caused by the peroxo groups on the Ti(OH)4 surface.

The ability to control the assembly of nanoparticles on substrates used in plasmon-enhanced spectroscopy continues to drive research in the field of nanofabrication. Here we describe the use of fungi as soft biotemplates to fabricate nanostructured microtubules with gold and gold-silver nanoparticles with potential applications as sensors and biosensors. In the first step, spores of the filamentous fungus Cladosporium sphaerospermum were inoculated in a suspension of gold nanoparticles, forming stable microtubules of gold nanoparticles during fungus growth. These materials were exposed to a second suspension of silver nanoparticles, resulting in complexes multilayers structures of gold and silver nanoparticles, which were evaluated as substrates for surface-enhanced Raman scattering (SERS) using small amounts of thiophenol as probe molecules directly on the microtubules. Both gold and the gold-silver substrates provide the SERS effect.