Effect of Cry1F maize on the behavior of susceptible and resistant Spodoptera frugiperda and Ostrinia nubilalis

Understanding the behavior of pests targeted with Bacillus thuringiensis Berliner (Bt) crops is important to define resistance management strategies. Particularly the study of larval movement between plants is important to determine the feasibility of refuge configurations. Exposure to Bt maize, Zea mays L. (Poaceae), has been suggested to increase larval movement in lepidopteran species but few studies have examined the potential for resistance to interact with behavioral responses to Bt toxins. Choice and no‐choice experiments were conducted with Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae) and Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae) to determine whether Cry1F resistance influences neonate movement. Leaf discs of Cry1F maize and the corresponding isoline were used to characterize behavioral responses. In both experiments, the location (on or off of plant tissues) and mortality of susceptible and Cry1F resistant neonates was recorded for 5 days, but the analysis of larvae location was performed until 7 h. Our results indicated no strong difference between resistant and susceptible phenotypes in S. frugiperda and O. nubilalis, although a small percentage of susceptible neonates in both species abandoned maize tissue expressing Cry1F. However, significant behavioral differences were observed between species. Ostrinia nubilalis exhibited increased movement between leaf discs, whereas S. frugiperda selected plant tissue within the first 30 min and remained on the chosen plant regardless of the presence of Cry1F. Spodoptera frugiperda reduced larval movement may have implications to refuge configuration. This study represents the first step toward understanding the effects of Cry1F resistance on Lepidoptera larval behavior. Information regarding behavioral differences between species could aid in developing better and more flexible resistance management strategies.     

Potential of some Metarhizium anisopliae isolates for control of Culex quinquefasciatus (Dipt., Culicidae)

Abstract: The potential of some isolates of Metarhizium anisopliae and Beauveria bassiana for use in the integrated management of Culex quinquefasciatus was evaluated. Metarhizium anisopliae isolate 1037 was selected in initial bioassays with a 50% lethal concentration (LC₅₀) of 1.97 × 10⁴ conidia/ml. This fungus caused higher mosquito larva mortality when applied as a conidial suspension to the surface of the water than as dry conidia, with a time to 50% lethal (LT₅₀) of 1 day compared with 3.6 days for the dry conidial application. However, results with UV- and heat-inactivated conidia did not confirm a possible role of fungal toxins in causing mortality when ingested by C. quinquefasciatus larvae. Metarhizium anisopliae did not remain active for as long as the bacterium Bacillus sphaericus isolate 2362. At 24 h after application, the fungus-induced mortality on mosquito larvae was significantly lower than the mortality caused by the bacterium. By the second day, almost no activity by the fungus was observed. Results suggest that M. anisopliae isolate 1037 has potential for use in mosquito control programmes.     

Essential oils from neotropical Myrtaceae: chemical diversity and biological properties

Myrtaceae family (121 genera, 3800-5800 spp.) is one of the most important families in tropical forests. They are aromatic trees or shrubs, which frequently produce edible fruits. In the neotropics, ca. 1000 species were found. Several members of this family are used in folk medicine, mainly as an antidiarrheal, antimicrobial, antioxidant, cleanser, antirheumatic, and anti-inflammatory agent and to decrease the blood cholesterol. In addition, some fruits are eaten fresh or used to make juices, liqueurs, and sweets very much appreciated by people. The flavor composition of some fruits belonging to the Myrtaceae family has been extensively studied due to their pleasant and intense aromas. Most of the essential oils of neotropical Myrtaceae analyzed so far are characterized by predominance of sesquiterpenes, some with important biological properties. In the present work, chemical and pharmacological studies carried out on neotropical Myrtaceae species are reviewed, based on original articles published since 1980. The uses in folk medicine and chemotaxonomic importance of secondary metabolites are also briefly discussed.     

Involvement of L-type calcium channel and SERCA2a in myocardial dysfunction induced by obesity

Obesity has been shown to impair myocardial performance. Nevertheless, the mechanisms underlying the participation of calcium (Ca(2+) ) handling on cardiac dysfunction in obesity models remain unknown. L-type Ca(2+) channels and sarcoplasmic reticulum (SR) Ca(2+) -ATPase (SERCA2a), may contribute to the cardiac dysfunction induced by obesity. The purpose of this study was to investigate whether myocardial dysfunction in obese rats is related to decreased activity and/or expression of L-type Ca(2+) channels and SERCA2a. Male 30-day-old Wistar rats were fed standard (C) and alternately four palatable high-fat diets (Ob) for 15 weeks. Obesity was determined by adiposity index and comorbidities were evaluated. Myocardial function was evaluated in isolated left ventricle papillary muscles under basal conditions and after inotropic and lusitropic maneuvers. L-type Ca(2+) channels and SERCA2a activity were determined using specific blockers, while changes in the amount of channels were evaluated by Western blot analysis. Phospholamban (PLB) protein expression and the SERCA2a/PLB ratio were also determined. Compared with C rats, the Ob rats had increased body fat, adiposity index and several comorbidities. The Ob muscles developed similar baseline data, but myocardial responsiveness to post-rest contraction stimulus and increased extracellular Ca(2+) was compromised. The diltiazem promoted higher inhibition on developed tension in obese rats. In addition, there were no changes in the L-type Ca(2+) channel protein content and SERCA2a behavior (activity and expression). In conclusion, the myocardial dysfunction caused by obesity is related to L-type Ca(2+) channel activity impairment without significant changes in SERCA2a expression and function as well as L-type Ca(2+) protein levels.     

Finite element analysis of peri-implant bone volume affected by stresses around Morse taper implants: effects of implant positioning to the bone crest

Abstract

Objectives: The purpose of the present study was to evaluate the distribution and magnitude of stresses through the bone tissue surrounding Morse taper dental implants at different positioning relative to the bone crest. Materials and Methods: A mandibular bone model was obtained from a computed tomography scan. A three-dimensional (3D) model of Morse taper implant-abutment systems placed at the bone crest (equicrestal) and 2?mm bellow the bone crest (subcrestal) were assessed by finite element analysis (FEA). FEA was carried out on axial and oblique (45°) loading at 150 N relatively to the central axis of the implant. The von Mises stresses were analysed considering magnitude and volume of affected peri-implant bone. Results: On vertical loading, maximum von Mises stresses were recorded at 6-7?MPa for trabecular bone while values ranging from 73 up to 118?MPa were recorded for cortical bone. On oblique loading at the equiquestral or subcrestal positioning, the maximum von Mises stresses ranged from 15 to 21?MPa for trabecular bone while values at 150?MPa were recorded for the cortical bone. On vertical loading, >99.9vol.% cortical bone volume was subjected to a maximum of 2?MPa while von Mises stress values at 15?MPa were recorded for trabecular bone. On oblique loading, >99.9vol.% trabecular bone volume was subjected to maximum stress values at 5?MPa, while von Mises stress values at 35?MPa were recorded for >99.4vol.% cortical bone. Conclusions: Bone volume-based stress analysis revealed that most of the bone volume (>99% by vol) was subjected to significantly lower stress values around Morse taper implants placed at equicrestal or subcrestal positioning. Such analysis is commentary to the ordinary biomechanical assessment of dental implants concerning the stress distribution through peri-implant sites.     

Carvedilol Decrease IL-1β and TNF-α, Inhibits MMP-2, MMP-9, COX-2, and RANKL Expression,and Up-Regulates OPG in a Rat Model of Periodontitis

Periodontal diseases are initiated primarily by Gram-negative, tooth-associated microbial biofilms that elicit a host response that causes osseous and soft tissue destruction. Carvedilol is a β-blocker used as a multifunctional neurohormonal antagonist that has been shown to act not only as an anti-oxidant but also as an anti-inflammatory drug. This study evaluated whether Carvedilol exerted a protective role against ligature-induced periodontitis in a rat model and defined how Carvedilol affected metalloproteinases and RANKL/RANK/OPG expression in the context of bone remodeling. Rats were randomly divided into 5 groups (n = 10/group): (1) non-ligated (NL), (2) ligature-only (LO), and (3) ligature plus Carvedilol (1, 5 or 10 mg/kg daily for 10 days). Periodontal tissue was analyzed for histopathlogy and using immunohistochemical analysis characterized the expression profiles of MMP-2, MMP-9, COX-2, and RANKL/RANK/OPG and determined the presence of IL-1β, IL-10 and TNF-α, myeloperoxidase (MPO), malonaldehyde (MDA) and, glutathione (GSH). MPO activity in the group with periodontal disease was significantly increased compared to the control group (p<0.05). Rats treated with 10 mg/kg Carvedilol presented with significantly reduced MPO and MDA concentrations (p<0.05) in addition to presenting with reduced levels of the pro-inflammatory cytokines IL-1 β and TNF-α (p<0.05). IL-10 levels in Carvedilol-treated rats remained unaltered. Immunohistochemical analysis demonstrated reduced expression of MMP-2, MMP-9, RANK, RANKL, COX-2, and OPG in rats treated with 10 mg/kg Carvedilol. This study demonstrated that Carvedilol affected bone formation/destruction and anti-inflammatory activity in a rat model of periodontitis.     

Inhibiting AKT Phosphorylation Employing Non-Cytotoxic Anthraquinones Ameliorates TH2 Mediated Allergic Airways Disease and Rhinovirus Exacerbation

Background

Severe asthma is associated with T helper (T_H) 2 and 17 cell activation, airway neutrophilia and phosphoinositide-3-kinase (PI3K) activation. Asthma exacerbations are commonly caused by rhinovirus (RV) and also associated with PI3K-driven inflammation. Anthraquinone derivatives have been shown to reduce PI3K-mediated AKT phosphorylation in-vitro.

Objective

To determine the anti-inflammatory potential of anthraquinones in-vivo.

Methods

BALB/c mice were sensitized and challenged with crude house dust mite extract to induce allergic airways disease and treated with mitoxantrone and a novel non-cytotoxic anthraquinone derivative. Allergic mice were also infected with RV1B to induce an exacerbation.

Results

Anthraquinone treatment reduced AKT phosphorylation, hypoxia-inducible factor-1α and vascular endothelial growth factor expression, and ameliorated allergen- and RV-induced airways hyprereactivity, neutrophilic and eosinophilic inflammation, cytokine/chemokine expression, mucus hypersecretion, and expression of T_H2 proteins in the airways. Anthraquinones also boosted type 1 interferon responses and limited RV replication in the lung.

Conclusion

Non-cytotoxic anthraquinone derivatives may be of therapeutic benefit for the treatment of severe and RV-induced asthma by blocking pro-inflammatory pathways regulated by PI3K/AKT.     

Cryptococcus festucosus sp. nov. a new hymenomycetous yeast in the Holtermannia clade

Five yeast strains belonging to the genus Cryptococcus Vuillemin were isolated from steppe plants and turf collected in the Prioksko-terrasny biosphere reserve (Moscow region, Russia). Sequence analyses of the D1/D2 domains of the 26S rDNA and of the internal transcribed spacer region revealed that these yeast strains and strain CBS 8016 have almost identical sequences and belong to the Holtermannia clade of the Tremellomycetidae (Basidiomycota, Hymenomycetes). A novel species named Cryptococcus festucosus (type strain VKM Y-2930) is proposed to accommodate these strains. Physiological characteristics and mycocin sensitivity patterns distinguishing Cryptococcus festucosus from the other species of this clade are presented.     

Lipid transfer proteins in coffee: isolation of Coffea orthologs,Coffea arabica homeologs,expression during coffee fruit development and promoter analysis in transgenic tobacco plants

The aim of the present study was to perform a genomic analysis of non-specific lipid-transfer proteins (nsLTPs) in coffee. Several nsLTPs-encoding cDNA and gene sequences were cloned from Coffea arabica and Coffea canephora species. In this work, their analyses revealed that coffee nsLTPs belong to Type II LTP characterized under their mature forms by a molecular weight of around 7.3 kDa, a basic isoelectric points of 8.5 and the presence of typical CXC pattern, with X being an hydrophobic residue facing towards the hydrophobic cavity. Even if several single nucleotide polymorphisms were identified in these nsLTP-coding sequences, 3D predictions showed that they do not have a significant impact on protein functions. Northern blot and RT-qPCR experiments revealed specific expression of Type II nsLTPs-encoding genes in coffee fruits, mainly during the early development of endosperm of both C. arabica and C. canephora. As part of our search for tissue-specific promoters in coffee, an nsLTP promoter region of around 1.2 kb was isolated. It contained several DNA repeats including boxes identified as essential for grain specific expression in other plants. The whole fragment, and a series of 5′ deletions, were fused to the reporter gene β-glucuronidase (uidA) and analyzed in transgenic Nicotiana tabacum plants. Histochemical and fluorimetric GUS assays showed that the shorter (345 bp) and medium (827 bp) fragments of nsLTP promoter function as grain-specific promoters in transgenic tobacco plants.     

Phythochemical screening and anticonvulsant activity of Cymbopogon winterianus Jowitt (Poaceae) leaf essential oil in rodents

Cymbopogon winterianus (Poaceae) is used for its analgesic, anxiolytic and anticonvulsant properties in Brazilian folk medicine. This report aimed to perform phythochemical screening and to investigate the possible anticonvulsant effects of the essential oil (EO) from fresh leaves of C. winterianus in different models of epilepsy. The phytochemical analysis of EO showed presence of geraniol (40.06%), citronellal (27.44%) and citronellol (10.45%) as the main compounds. A behavioral screening demonstrated that EO (100, 200 and 400 mg/kg; ip) caused depressant activity on CNS. When administered concurrently, EO (200 and 400 mg/kg, ip) significantly reduced the number of animals that exhibited PTZ- and PIC-induced seizures in 50% of the experimental animals (p<0.05). Additionally, EO (100, 200 and 400 mg/kg, ip) significantly increased (p<0.05) the latencies of clonic seizures induced by STR. Our results demonstrated a possible activity anticonvulsant of the EO.