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Lufenuron, a molecule that belongs to the chitin synthesis inhibitors group of insect growth regulators, has a still unclear mode of action, but probably it affects chitin synthesis at a post‐transcriptional level. In this work, we report the effects of lufenuron on nutrition and reproduction in adult females of Anthonomus grandis, the main neotropical cotton pest and tried to link the effects on peritrophic matrix (PM) with egg viability. After Lufenuron treatment A. grandis females presented weight loss and less accumulation of protein and lipids probably due to PM breakdown. Also, treated females produce the same quantity of eggs as the control, although eggs from lufenuron‐treated females were less viable. After morphological and histochemical analysis, we have noticed that oocytes from lufenuron‐treated females contained less protein. Finally, lufenuron‐treated females produced at least nine times less vitellogenin (AgraVg) RNA than control females. We specifically showed that lufenuron treatment caused PM disruption and it has probably led to vitellogenin (AgraVg) downregulation in females culminating in egg unviability. The effect of lufenuron on PM leads to insect malnutrition, and this malnutrition downregulates vitellogenin among other genes. This is the first work that describes and tries to correlate the lufenuron effects on adult females. [ABSTRACT FROM AUTHOR]

BACKGROUND: Lectins from Moringa oleifera seeds (WSMoL), Myracrodruon urundeuva bark (MuBL), and heartwood (MuHL) are larvicidal agents against Aedes aegypti; in addition, WSMoL is an ovicidal agent against this mosquito. In this work, we evaluated the ovicidal activity of MuBL and MuHL by determining the concentrations that reduce the hatching rates by 50% in 72 h (EC50). The effects of WSMoL, MuBL, and MuHL on the ultrastructure of the eggs' surface were assessed by scanning electron microscopy (SEM). In addition, the ability of these lectins to penetrate the eggs was investigated by using conjugates of the lectins with fluorescein isothiocyanate (FITC). RESULTS: MuBL and MuHL were ovicidal agents with EC50 of 0.26 and 0.80 mg/mL (260 and 800 ppm), respectively. SEM images of eggs treated with WSMoL for 24 h revealed discontinuity of the exochorionic network and the absence of the exochorionic cells and their tubercles. After 48 and 72 h of incubation, strong deformation and degeneration of egg surfaces were observed. In MuBL and MuHL‐treated eggs, the presence of lumps on the surface of the eggs, disappearance of the exochorionic network and the decrease and deformation of tubercles were observed. Lastly, fluorescence microscopy revealed that the three lectins were able to enter the eggs and reach the digestive tract of the embryos. CONCLUSION: WSMoL, MuBL, and MuHL are ovicidal agents on A. aegypti that have differing efficiencies in terms of how they cause alterations in the chorionic surface and in terms of their ability to penetrate the eggs. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Metabolic demands such as growth and reproduction of insects relate directly to the fat body. This organ is responsible for the biosynthesis and storage of nutrients, and participates in the neutralization and detoxification of xenobiotics. Studies show a relationship between its ability to accumulate nutrients and activities, such as diapause and reproduction in the beetle Anthonomus grandis, an important pest of cotton plants. However, there are no detailed studies on the structure and histochemistry of the fat body in this insect. We describe the ultrastructure and histochemistry of the fat body in A. grandis and discuss some of its characteristic features. The fat body is composed of a single cell type, the trophocyte, which is a voluminous cell with a spherical or bilobed nucleus, and cytoplasm containing several lipid droplets, glycogen granules (electron-dense), and protein granules. These trophocytes have few areas of contact with each other and form lobes, enclosed by connective tissue. A high metabolic activity of the fat body is deduced by the intense histochemical staining for protein and polysaccharide compounds, demonstrating that specific processes, such as the synthesis and secretion of vitellogenin, could be a target for more specific studies on methods to control this insect. [ABSTRACT FROM AUTHOR]

The article focuses on an attack by smooth hammerhead sharks on some pantropical spotted dolphins in waters off Brazil, and discusses some features of group antipredation tactics. A linear regression model was used to examine the relationship between distances from adult dolphins followed by sharks to subgroups.

Leishmaniasis is considered by the World Health Organization as one of the infectious parasitic diseases endemic of great relevance and a global public health problem. Pentavalent antimonials used for treatment of this disease are limited and new phytochemicals emerge as an alternative to existing treatments, due to the low toxicity and cost reduction. Usnic acid is uniquely found in lichens and is especially abundant in genera such as Alectoria, Cladonia, Evernia, Lecanora, Ramalina, and Usnea. Usnic acid has been shown to exhibit antiviral, antiprotozoal, antiproliferative, anti-inflammatory, and analgesic activity. The aim of this study was to evaluate the antileishmanial activity of usnic acid on Leishmania infantum chagasi promastigotes and the occurrence of drug-induced ultrastructural damage in the parasite. Usnic acid was effective against the promastigote forms (IC50 = 18.30 ± 2.00 µg/mL). Structural and ultrastructural aspects of parasite were analyzed. Morphological alterations were observed as blebs in cell membrane and shapes given off, increasing the number of cytoplasmic vacuoles, and cellular and mitochondrial swelling, with loss of cell polarity. We concluded that the usnic acid presented antileishmanial activity against promastigote forms of Leishmania infantum chagasi and structural and ultrastructural analysis reinforces its cytotoxicity. Further, in vitro studies are warranted to further evaluate this potential. [ABSTRACT FROM AUTHOR]

Background: Among the several challenges faced by bloodsucking arthropods, the vertebrate hemostatic response against blood loss represents an important barrier to efficient blood feeding. Here we report the first inhibitor of collagen-induced platelet aggregation derived from the salivary glands of a black fly (Simulium nigrimanum), named Simplagrin. Methods and Findings: Simplagrin was expressed in mammalian cells and purified by affinity-and size-exclusion chromatography. Light-scattering studies showed that Simplagrin has an elongated monomeric form with a hydrodynamic radius of 5.6 nm. Simplagrin binds to collagen (type I-VI) with high affinity (2–15 nM), and this interaction does not involve any significant conformational change as determined by circular dichroism spectroscopy. Simplagrin-collagen interaction is both entropically and enthalpically driven with a large negative ΔG, indicating that this interaction is favorable and occurs spontaneously. Simplagrin specifically inhibits von Willebrand factor interaction with collagen type III and completely blocks platelet adhesion to collagen under flow conditions at high shear rates; however, Simplagrin failed to block glycoprotein VI and Iα2β1 interaction to collagen. Simplagrin binds to RGQOGVMGF peptide with an affinity (KD 11 nM) similar to that of Simplagrin for collagen. Furthermore, Simplagrin prevents laser-induced carotid thrombus formation in vivo without significant bleeding in mice and could be useful as an antithrombotic agent in thrombosis related disease. Conclusion: Our results support the orthology of the Aegyptin clade in bloodsucking Nematocera and the hypothesis of a faster evolutionary rate of salivary function of proteins from blood feeding arthropods. [ABSTRACT FROM AUTHOR]

The IBM eServer™ zSeries® Model z990 offers customers significant new opportunity for server growth while preserving and enhancing server availability. The z990 provides vertical growth capability by introducing the concurrent addition of processor/memory books and horizontal growth in channels by the use of extended virtualization technology. In order to continue to support the zSeries legacy for high availability and continuous reliable operation, the z990 delivers significant new features for reliability, availability, and serviceability (RAS). This paper describes these new capabilities, in each case presenting the value of the feature, both in terms of enhancing the self-management capability of the server and its availability. [ABSTRACT FROM AUTHOR]

Leishmaniasis is considered by the World Health Organization as one of the infectious parasitic diseases endemic of great relevance and a global public health problem. Pentavalent antimonials used for treatment of this disease are limited and new phytochemicals emerge as an alternative to existing treatments, due to the low toxicity and cost reduction. Usnic acid is uniquely found in lichens and is especially abundant in genera such as Alectoria, Cladonia, Evernia, Lecanora, Ramalina, and Usnea. Usnic acid has been shown to exhibit antiviral, antiprotozoal, antiproliferative, anti-inflammatory, and analgesic activity. The aim of this study was to evaluate the antileishmanial activity of usnic acid on Leishmania infantum chagasi promastigotes and the occurrence of drug-induced ultrastructural damage in the parasite. Usnic acid was effective against the promastigote forms (IC50=18.30±2.00 µg/mL). Structural and ultrastructural aspects of parasite were analyzed. Morphological alterations were observed as blebs in cell membrane and shapes given off, increasing the number of cytoplasmic vacuoles, and cellular and mitochondrial swelling, with loss of cell polarity. We concluded that the usnic acid presented antileishmanial activity against promastigote forms of Leishmania infantum chagasi and structural and ultrastructural analysis reinforces its cytotoxicity. Further, in vitro studies are warranted to further evaluate this potential.

Botos (Inia geoffrensis) are currently provisioned for use in tourist attractions in five sites in the Brazilian Amazon. Despite the known negative effects associated with human-wild dolphin interactions, this activity has been regulated and licensed in the Anavilhanas National Park in Novo Airão, Amazonas State, Brazil. We present an updated evaluation of the perception of the local community concerning the possible socioeconomic impacts of this tourism in Novo Airão. In April 2011, 45 interviews were conducted with inhabitants. A small segment of Novo Airão perceives currently itself as being economically dependent on the botos feeding tourism. Despite that, the economic benefits of this controversial activity apparently are not shared among most inhabitants, and botos feeding tourism is perceived as generating diverse negative effects. We conclude that if the activity was banned or modified into a less impacting tourist activity, this action would probably not majorly affect the lives of the general population.

We aimed to characterize the morphology and ultrastructure of hemocytes of Nasutitermes coxipoensis (Holmgren) workers and to quantify the cell types 24 h, 48 h and 72 h after inoculation with Metarhizium anisopliae. Six hemocytes types were identified, plasmatocyte, granulocyte, spherulocyte, prohemocyte, adipohemocyte and eonocytoid Hemocytes did not present any morphological alteration at the several observation periods, but they did have a change in their abundance, as observed for spherulocytes, adipohemocytes and eonocytoids at all intervals, and for plasmatocytes and granulocytes at 48 h after host inoculation. We argue on the possible reasons and implications of the observed changes.