scholarly journals Geosmin attractsAedes aegyptimosquitoes to oviposition sites

2019 ◽  
Author(s):  
Nadia Melo ◽  
Gabriella H. Wolff ◽  
Andre Luis Costa-da-Silva ◽  
Robert Arribas ◽  
Merybeth Fernandez Triana ◽  
...  
Keyword(s):  
Site Selection ◽  
Mosquito Control ◽  
Egg Laying ◽  
Multiphoton Imaging ◽  
Vinegar Fly ◽  
Extreme Sensitivity ◽  
High Degree ◽  
Oviposition Sites ◽  
Peel Extract

Geosmin is one of the most recognizable and common microbial smells on the planet. Some insects, like mosquitoes, require microbial-rich environments for their progeny, whereas for other insects such microbes may prove dangerous. In the vinegar flyDrosophila melanogaster, geosmin is decoded in a remarkably precise fashion and induces aversion, presumably signaling the presence of harmful microbes. We have here investigated the effect of geosmin on the behavior of the yellow fever mosquitoAedes aegypti. In contrast to flies, geosmin is not aversive in mosquitoes but stimulates egg-laying site selection. Female mosquitoes could associate geosmin with microbes, including cyanobacteria consumed by larvae, who also find geosmin – as well as geosmin producing cyanobacteria – attractive. Usingin vivomultiphoton imaging from mosquitoes with pan-neural expression of the calcium reporter GCaMP6s, we show thatAe. aegypticode geosmin in a similar fashion to flies, i.e. with extreme sensitivity and with a high degree of selectivity. We further demonstrate that geosmin can be used as bait under field conditions, and finally we show that geosmin, which is both expensive and difficult to obtain, can be substituted by beetroot peel extract, providing a cheap and viable mean of mosquito control and surveillance in developing countries.

Reproductive Site Selection: Evidence of an Oviposition Cue in a Highly Adaptive Dipteran, Drosophila suzukii (Diptera: Drosophilidae)

2020 ◽  
Vol 49 (2) ◽  
pp. 355-363 ◽  
Author(s):  
Gabriella Tait ◽  
Kyoo Park ◽  
Rachele Nieri ◽  
M Cristina Crava ◽  
Serhan Mermer ◽  
...  
Keyword(s):  
Site Selection ◽  
Control Strategies ◽  
Drosophila Suzukii ◽  
Larval Stages ◽  
Video Recordings ◽  
Photographic Evidence ◽  
Vinegar Fly ◽  
Synthetic Blend ◽  
Oviposition Sites ◽  
Selection Of

Abstract Drosophila suzukii (Matsumura) is a vinegar fly species that originates from Eastern Asia and has spread throughout Europe and the Americas since its initial detection in United States in 2008. Its relatively large, sclerotized, and serrated ovipositor enables the ability to penetrate ripening fruits, providing a protected environment for its egg and larval stages. Because the mechanism of oviposition site selection of D. suzukii is a matter of hypothesis, the aim of the present study was to elucidate behavioral and chemical aspects of short-range ovipositional site selection within the context of D. suzukii reproductive biology. The preference of D. suzukii to lay eggs on artificially pierced, previously infested, or intact fruits was tested. Video recordings and photographic evidence documented the release of an anal secretion over the fruit surface near the oviposition sites. Gas chromatographic analysis revealed the presence of 11 compounds detected only on the skin of egg-infested berries. Electroantennographic experiments with both sexes of D. suzukii highlighted the importance of six volatile compounds: methyl myristate, methyl palmitate, myristic acid, lauric acid, palmitic acid, and palmitoleic acid. Finally, a synthetic blend composed of the six compounds in a ratio similar to that found on the skin of egg-infested berries increased the oviposition rate of conspecific females. Data from our work suggest that the identified volatiles are cues for reproductive site selection. We discuss how these oviposition cues may affect the fitness of D. suzukii. The knowledge gained from this study may accelerate establishment of control strategies based on the interference and disruption of D. suzukii communication during the oviposition processes.

Preparation and Biochemical Evaluation of Functionalized Multi-Walled Carbon Nanotubes with Punica granatum Extract

2019 ◽  
Vol 15 (1) ◽  
pp. 138-144 ◽  
Author(s):  
Ahmed A. Haroun ◽  
Abdel-Tawab H. Mossa ◽  
Samia M.M. Mohafrash
Keyword(s):  
Liver Enzymes ◽  
Histopathological Analysis ◽  
Pomegranate Peel ◽  
Liver And Kidney ◽  
Multi Walled Carbon Nanotubes ◽  
Pomegranate Peel Extract ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts ◽  
Peel Extract

Background: Funcionalized multi-walled carbon nanotubes (ox-MWCNTs) were used for the preparation of therapeutic nanoparticles for delivery of some bioactive compounds. Consequently, this work deals with the preparation of grafted MWCNTs with n-vinyl caprolactam in the presence of pomegranate peel extract (P. granatum), titanium dioxide (TiO2) and/or silver nanoparticeles and their toxic effects on male mice using in vivo biological examination (liver and kidney dysfunction biomarkers) and the histopathological analysis. Methods: P. granatum extract was immobilized onto functionalized MWCNTs using simple adsorption technique. Moreover, The prepared materials were analyzed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM). In vivo examination using liver and kidney dysfunction biomarkers was investigated. In addition, the histopathological study was carried out. Results: The ox-MWCNTs induced significant elevation in the liver enzymes including AST, ALT and ALP relative to the control group. While, the treatment with P. granatum extract only did not induce any change in the liver and kidney biomarkers. In other words, P. granatum extract loaded onto functionalized MWCNTs showed low effects on liver enzymes and kidney function biomarkers in the treated mice in comparison with ox-MWCNTs and extract separately. Moreover, histopathological analysis revealed that the P. granatum extract functionalized MWCNTs exhibited normal renal tissue with no histopathological alteration. Conclusion: The grafted MWCNTs with n-vinyl caprolactam in the presence of pomegranate peel extract (P. granatum), titanium dioxide (TiO2) and/or silver nanoparticeles were successfully prepared. SEM-micrographs showed complete coating of MWCNTs fiber with the extract. The prepared materials resulted in no toxic effects and the histopathological findings were confirmed by inflammation of the liver and kidney tissues.

scholarly journals Compensatory mechanisms in resistant Anopheles gambiae AcerKis and KdrKis neurons modulate insecticide-based mosquito control

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Stéphane Perrier ◽  
Eléonore Moreau ◽  
Caroline Deshayes ◽  
Marine El-Adouzi ◽  
Delphine Goven ◽  
...  
Keyword(s):  
Sodium Channel ◽  
Anopheles Gambiae ◽  
Calcium Concentration ◽  
Mosquito Control ◽  
Point Mutations ◽  
Resting Membrane Potential ◽  
Compensatory Mechanisms ◽  
Pyrethroid Insecticides

AbstractIn the malaria vector Anopheles gambiae, two point mutations in the acetylcholinesterase (ace-1R) and the sodium channel (kdrR) genes confer resistance to organophosphate/carbamate and pyrethroid insecticides, respectively. The mechanisms of compensation that recover the functional alterations associated with these mutations and their role in the modulation of insecticide efficacy are unknown. Using multidisciplinary approaches adapted to neurons isolated from resistant Anopheles gambiae AcerKis and KdrKis strains together with larval bioassays, we demonstrate that nAChRs, and the intracellular calcium concentration represent the key components of an adaptation strategy ensuring neuronal functions maintenance. In AcerKis neurons, the increased effect of acetylcholine related to the reduced acetylcholinesterase activity is compensated by expressing higher density of nAChRs permeable to calcium. In KdrKis neurons, changes in the biophysical properties of the L1014F mutant sodium channel, leading to enhance overlap between activation and inactivation relationships, diminish the resting membrane potential and reduce the fraction of calcium channels available involved in acetylcholine release. Together with the lower intracellular basal calcium concentration observed, these factors increase nAChRs sensitivity to maintain the effect of low concentration of acetylcholine. These results explain the opposite effects of the insecticide clothianidin observed in AcerKis and KdrKis neurons in vitro and in vivo.

scholarly journals Precision radiogenomics: fusion biopsies to target tumour habitats in vivo

2021 ◽  
Author(s):  
Mireia Crispin-Ortuzar ◽  
Evis Sala
Keyword(s):  
Ovarian Cancer ◽  
Ct Scans ◽  
High Grade ◽  
Serous Ovarian Cancer ◽  
High Degree ◽  
Degree Of Heterogeneity

SummaryHigh-grade serous ovarian cancer lesions display a high degree of heterogeneity on CT scans. We have recently shown that regions with distinct imaging profiles can be accurately biopsied in vivo using a technique based on the fusion of CT and ultrasound scans.

scholarly journals Formulation and Mathematical Optimization of Controlled Release Calcium Alginate Micro Pellets of Frusemide

2013 ◽  
Vol 2013 ◽  
pp. 1-14 ◽  
Author(s):  
Amitava Ghosh ◽  
Prithviraj Chakraborty
Keyword(s):  
Sodium Alginate ◽  
Calcium Alginate ◽  
Mathematical Optimization ◽  
Extended Period ◽  
Cost Effective ◽  
Polynomial Equation ◽  
Chronic Hypertension ◽  
Order Polynomial ◽  
High Degree

Objective. Frusemide loaded calcium alginate micropellets, an oral microparticulate delivery system, was statistically optimized exhibiting prolonged therapeutic action minimizing its adverse effects.Methods. Ionotropic Gelation technique was adopted employing 32Factorial designs and keeping the entire process free from organic solvents. Physicochemical and the release characteristics of the prepared formulations were studied, keeping variations only in sodium alginate (primary polymer) and Acrycoat E30D (copolymer) dispersion.Result. Sodium alginate was predominant over Acrycoat E30D in all batches. Nonadditives or interaction was observed to be insignificant. Multiple regressions produced second-order polynomial equation, and the predictive results obtained were validated with high degree of correlation. Thein vivostudy applauded that optimized calcium alginate micropellets of frusemide can produce a much greater diuretic effect over an extended period of 24 hours.Conclusion. This study reveals that the potential of a single dose of the mathematically optimized micro pellets of frusemide formulation is sufficient in the management of peripheral edema and ascites in congestive heart failure and as well in the treatment of chronic hypertension, leading to better patient compliance, and can be produced with minimum experimentation and time, proving far more cost-effective formulation than the conventional methods of formulating dosage forms.

scholarly journals The anti-angiogenic isoforms of VEGF in health and disease

2009 ◽  
Vol 37 (6) ◽  
pp. 1207-1213 ◽  
Author(s):  
Yan Qiu ◽  
Coralie Hoareau-Aveilla ◽  
Sebastian Oltean ◽  
Steven J. Harper ◽  
David O. Bates
Keyword(s):  
Splice Site ◽  
Site Selection ◽  
Age Related Macular Degeneration ◽  
Splicing Factor ◽  
Splice Site Selection ◽  
Age Related ◽  
Normal Human ◽  
Radical Revision

Anti-angiogenic VEGF (vascular endothelial growth factor) isoforms, generated from differential splicing of exon 8, are widely expressed in normal human tissues but down-regulated in cancers and other pathologies associated with abnormal angiogenesis (cancer, diabetic retinopathy, retinal vein occlusion, the Denys–Drash syndrome and pre-eclampsia). Administration of recombinant VEGF165b inhibits ocular angiogenesis in mouse models of retinopathy and age-related macular degeneration, and colorectal carcinoma and metastatic melanoma. Splicing factors and their regulatory molecules alter splice site selection, such that cells can switch from the anti-angiogenic VEGFxxxb isoforms to the pro-angiogenic VEGFxxx isoforms, including SRp55 (serine/arginine protein 55), ASF/SF2 (alternative splicing factor/splicing factor 2) and SRPK (serine arginine domain protein kinase), and inhibitors of these molecules can inhibit angiogenesis in the eye, and splice site selection in cancer cells, opening up the possibility of using splicing factor inhibitors as novel anti-angiogenic therapeutics. Endogenous anti-angiogenic VEGFxxxb isoforms are cytoprotective for endothelial, epithelial and neuronal cells in vitro and in vivo, suggesting both an improved safety profile and an explanation for unpredicted anti-VEGF side effects. In summary, C-terminal distal splicing is a key component of VEGF biology, overlooked by the vast majority of publications in the field, and these findings require a radical revision of our understanding of VEGF biology in normal human physiology.

Reproduction in Aplysia californica: correlations between egg laying in vivo and egg release in vitro

1980 ◽  
Vol 58 (11) ◽  
pp. 2163-2166 ◽  
Author(s):  
F. Edward Dudek ◽  
Amd Bonnie Soutar ◽  
Stephen S. Tobe
Keyword(s):  
Aplysia Californica ◽  
Egg Laying ◽  
Previous Episode ◽  
Laboratory Conditions ◽  
Release In Vitro

Aspects of egg laying by isolated Aplysia californica and egg release from ovotestis fragments were compared under laboratory conditions. The volume of eggs laid per episode increased as a function of time since the previous episode of egg laying. Egg output in vivo and egg release in vitro were maximal in autumn and minimal in spring, but a factor in the parietovisceral ganglion evoked egg release from ovotestis fragments throughout the year. These data are consistent with previous studies which have suggested that the effects of season and egg-laying history on egg laying involve substantial changes in the ovotestis.

scholarly journals Structural comparison of the rostra of two species of weevils coexisting on Ailanthus altissima: the response to ecological demands of egg deposition

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ganyu Zhang ◽  
Wenjuan Guo ◽  
Xiaoyi Wang ◽  
Qian Wang ◽  
Jin Cui ◽  
...  
Keyword(s):  
Adaptive Radiation ◽  
Egg Laying ◽  
Ailanthus Altissima ◽  
Structural Comparison ◽  
Structural Differentiation ◽  
Functional Potential ◽  
Egg Deposition ◽  
Adductor Muscles ◽  
Structural Differences ◽  
Oviposition Sites

Abstract Background Elongated rostra play an important role in the egg-laying of weevils, and its emergence plays a key role in the adaptive radiation of weevils. Eucryptorrhynchus scrobiculatus Motschulsky and E. brandti Harold co-occur on the same only host Ailanthus altissima, while their oviposition sites are different. In order to understand the adaptation between the rostra of the two weevils and their oviposition sites, the structural differentiation of the rostra in E. scrobiculatus and E. brandti was compared. Results The present study reveals that: (1) The rostra length of E. scrobiculatus and E. brandti was found to be correlated with body size, larger weevils have a correspondingly longer rostrum. The increase of rostra length may be a byproduct of larger weevils. (2) There were significant differences in the external shape of the two rostra, especially the shape of the mandibles of the mouthparts at the apex of the rostra used to excavate an oviposition cavity. (3) There was no difference in the size of the abductor muscles that control the extension of the mandibles, but there were significant differences in the size of the adductor muscles that control the contraction of the mandibles. Conclusions These structural differences reflect the functional potential ovipositional tactics of rostra, which is considered to be a response to the ecological demands of egg deposition, and also provide new insights into the coexistence of two weevil species in the same host A. altissima.

scholarly journals Bioactivity-Guided Investigation of the Anti-Inflammatory Activity of Hippophae rhamnoides Fruits

Planta Medica ◽  
2017 ◽  
Vol 84 (01) ◽  
pp. 26-33 ◽  
Author(s):  
Dóra Rédei ◽  
Norbert Kúsz ◽  
Nikoletta Jedlinszki ◽  
Gábor Blazsó ◽  
István Zupkó ◽  
...  
Keyword(s):  
Hippophae Rhamnoides ◽  
Inflammatory Activity ◽  
Hippophaë Rhamnoides ◽  
Rat Paw Edema ◽  
In Vivo Animal Models ◽  
Anti Inflammatory ◽  
Rat Paw ◽  
First Time ◽  
Peel Extract

AbstractAccording to modern ethnobotanical records, the fruit of Hippophae rhamnoides is effective in the treatment of different allergic symptoms. In order to obtain pharmacological evidence for this observation, the fruit was investigated for anti-inflammatory activity using in vivo animal models. Aqueous and 70% MeOH extracts were tested in 48/80-induced rat paw edema assay after oral administration, and it was found that the 70% MeOH extract (500 mg/kg) reduced significantly edema volume (0.660 ± 0.082 mL vs. control 0.935 ± 0.041 mL). Extracts of different parts of the fruit (pulp, peel, seed) were investigated in the same assay, and the peel extract was shown to exhibit maximum edema-reducing effect (0.470 ± 0.124 mL vs. control 0.920 ± 0.111 mL). This extract was used to elucidate the mode of action. Different inflammation inducers (serotonin, histamine, dextran, bradykinin, and carrageenan) were applied in the rat paw model, but the extract inhibited only the compound 48/80 elicited inflammation. The active extract was then fractionated by solvent-solvent partitioning and chromatographic methods with the guidance of the 48/80-induced anti-inflammatory assay, and the main compounds responsible for the activity were identified as ursolic acid and oleanolic acid. Our data suggest that the activity is most probably based on a membrane stabilizing effect caused by the inhibition of degranulation of mast cells. Moreover, previously unknown 2,5-bis-aryl-3,4-dimethyltetrahydrofuran lignans, nectandrin B, fragransin A2, and saucernetindiol were isolated and identified from H. rhamnoides for the first time.

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