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Abstract

Arthropods are the largest group of the living organisms. They attack other organisms by biting, stinging, or piercing and sucking. Among various medically important arthropods, which feed on living hosts, mosquitoes' piercing spread viruses which have been reported to cause the highest number of deaths annually. The primary cause of the deaths is malaria, which is spread by infected mosquitoes' piercing. This study aims at elucidating lessons from mosquitoes' painless piercing. Mosquitoes pierce using their fascicle, which is a bundle of coherently functioning six stylets. Based on experiments and available literature, it is presented that mosquitoes painlessly pierce using a combination of the numbing, the fascicle's serrated design, the vibratory actuation, and the graded and frequency-dependent mechanical properties of the labrum. Based on this understanding, a mosquito-inspired microneedle design has also been proposed.

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... Many invertebrates capable of penetrating solid substrates (especially mosquito and wasp) were also investigated in prior research to develop bio-inspired needles to improve needle insertion performance. Two common biological features were observed, the serrated/notched apparatuses and vibratory reciprocating motions [1][2][3][4][24][25][26] , which enabled easier piercing/penetration. Inspired by these features, an early study demonstrated the feasibility of harpoon-shape notches in a silicon needle tip for insertion into a soft tissue phantom 27 . In experiments of insertion into the tissue-mimicking phantom 1 and the ex-vivo tissue 28 , the notched needle tips exhibited lower insertion forces when compared to the needle without notches. ...
... The opposite needle-cannula motions (mimicking mosquito proboscis's insertion 1-3 ) in NCI and MPI insertions reduced the U A and U P compared to those of NCD insertion. The incremental advancements of needle and cannula generated vibratory insertion similar to that of a mosquito proboscis for easier penetration into soft tissue 4 . The cannula/needle retraction further created the opposite force to reduce the tissue deformation caused by the needle/cannula advancement during the incremental insertion. ...
... The cannula/needle retraction further created the opposite force to reduce the tissue deformation caused by the needle/cannula advancement during the incremental insertion. The tissue and organ displacement could also be stabilized and reduced 4,29 . The harpoon-shape notches at the needle tip (mimicking the mosquito's proboscis notches 1,5 ) in MPI insertion resulted in the much reduced U A and U P among three insertions. ...
Article
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This study investigates mosquito proboscis-inspired (MPI) insertion applied to the clinically used biopsy needle to reduce tissue deformation and organ displacement. Advanced medical imagining has enabled early-stage identification of cancerous lesions that require needle biopsy for minimally invasive tissue sampling and pathological analysis. Accurate cancer diagnosis depends on the accuracy of needle deployment to the targeted cancerous lesion site. However, currently available needle delivery systems deform and move soft tissue and organs, leading to a non-diagnostic biopsy or undersampling of the target. Two features inspired by the mosquito proboscis were adopted for MPI insertion in prostate biopsy: (1) the harpoon-shape notches at the needle tip and (2) reciprocating needle-cannula motions for incremental insertion. The local tissue deformation and global prostate displacement during the MPI vs. traditional direct insertions were quantified by optically tracking the displacement of particle-embedded tissue-mimicking phantoms. Results show that the MPI needle insertion reduced both local tissue deformation and global prostate displacement because of the opposite needle-cannula motions and notches which stabilized and reduced the tissue deformation during insertion. Findings provide proof of concept for MPI insertion in the clinical biopsy procedures as well as insights of needle–tissue interaction for future biopsy technology development.
... Some arthropods simply attack their prey with stingers and others feed on their host on plant nectar, blood, and other organisms. A few medically important arthropods are classified based on their attacking mechanism in Fig. 2 (Dickerson and Lavoipierre 1959;Durden and Mullen 2009;Chapman et al. 2013;Gurera et al. 2018). Arthropods are classified as biters, stingers, and piercers and suckers. ...
... In the first part, mosquitoes locomotory attributes, which are used by them to hunt a host, are described. Next, based on Gurera et al. (2018), microanatomy, feeding process, and nanomechanical properties data of mosquitoes' labrum are presented. A hypothesis behind the painless piercing is presented followed by mosquito-inspired microneedle design guidelines. ...
... Moreover, a mosquito weighs about 1-4 mg. The features mentioned, however, do not appear the same for both sexes of mosquitoes, as shown in Fig. 3 (bottom) (Gordon and Lavoipierre 1962; Gurera et al. 2018). Visually, male mosquitoes are smaller in size, have longer maxillary palps, and have more bushy antennas (Foster and Walker 2009). ...
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This paper provides an overview of lessons from mosquitoes’ locomotion and their painless piercing and from wasp stinging. Based on the understanding, conceptual schematics of bioinspired microneedle designs are presented for biomedical applications. In the first part, mosquitoes locomotory attributes, which are used by them to hunt a host, are described. Next, microanatomy, feeding process, and nanomechanical properties data of mosquitoes’ labrum are presented. A hypothesis behind the painless piercing is presented followed by mosquito-inspired microneedle design guidelines. In the second part, wasp anatomy and stinging process are described. Their structure and nanomechanical properties data, modeling of the penetration process, and stinger-inspired microneedle design guidelines are presented.
... Figure 1 provides an overview of various species and objects from living nature and their selected functions [2,4]. These include bacteria [12], plants [13][14][15], insects/spiders/lizards/frogs [16][17][18], aquatic animals [19][20][21][22][23][24], birds [25], structural coloration [26], seashells/bones/teeth [27][28][29][30][31][32][33], spider webs [11,34], insect piercing [35][36][37], moths' eyes [38,39], biological systems with a self-healing capability [40][41][42] and sensory-aid devices [11,43]. ...
... Leaves of water-repellent plants, such as Nelumbo nucifera (lotus), are known to be superhydrophobic, self-cleaning and antifouling, owing to hierarchical roughness (microbumps superimposed with a nanostructure) and the presence of a hydrophobic wax coating [2,4,44,49,50]. Water droplets on these surfaces readily sit on the [44]; the slippery rim (peristome) of the pitcher plant captures insects by insect aquaplaning [14]; water strider walking on water [45]; butterfly wing effect [46]; gecko foot exhibiting reversible adhesion [47]; scale structure of shark, reducing drag [48]; wings of a bird in landing approach; brilliant iridescent colours in bird and peacock feathers; nacre of the inner abalone shell showing mesostructure with mesolayers [31]; spider's web made of silk material [11]; mosquito with painless-piercing fascicle mouthpart [35,37]; antireflective moth's eye [38]; bruised or skinned knee which heals itself; and ears and eyes as examples of sensory-aid devices. ...
... Arthropods feed on various kinds of food, including plants, nectar, blood and flesh [36,37]. Among various medically important arthropods which feed on living hosts, mosquitoes have been reported to cause the highest number of deaths annually. ...
Article
Nature has developed materials, objects and processes that function from the macroscale to the nanoscale. The emerging field of biomimetics allows one to mimic biology or nature to develop nanomaterials, nanodevices and processes which provide desirable properties. The biologically inspired materials and structured surfaces are being explored for various commercial applications. These should have minimum human impact on the environment, leading to eco-friendly or green science and technology. There are a large number of flora and fauna including bacteria, plants, land and aquatic animals, and seashells with properties of commercial interest. The paper presents an overview of the general field of biomimetics followed by a detailed overview of mechanisms, fabrication techniques and characterization of superliquiphobic/philic surfaces and their applications. This article is part of the theme issue ‘Bioinspired materials and surfaces for green science and technology’.
... As a less painful alternative to the commonly used hypodermic needle for subcutaneous vaccine delivery, microneedles are micron-scale needles that provide a minimally invasive method for transcutaneous delivery of vaccine past the outermost layer of epidermis, the stratum corneum (SC), without activating the underlying pain receptors like conventional needles [134][135][136] (Figure 1). Available as solid, drug-coated, deep, dissolving, and hollow, microneedles may confer an advantage in vector-borne vaccine development in that they more closely mimic deposition of the pathogen or antigen into the skin microenvironment. ...
... Available as solid, drug-coated, deep, dissolving, and hollow, microneedles may confer an advantage in vector-borne vaccine development in that they more closely mimic deposition of the pathogen or antigen into the skin microenvironment. Indeed, bioengineers have now proposed a microneedle design based on the mosquito fascicle, a collection of six stylets with serrated design and vibration specialized for painless insertion into the skin [136]. Given the initial goal of all vector-borne pathogens is to survive the skin's initial immune assault, a vector-borne disease vaccine delivery model would also disrupt epithelium and drive antigen presentation within the pathogen's initial target tissue, the skin. ...
Article
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The current increase in vector-borne disease worldwide necessitates novel approaches to vaccine development targeted to pathogens delivered by blood-feeding arthropod vectors into the host skin. A concept that is gaining traction in recent years is the contribution of the vector or vector-derived components, like salivary proteins, to host-pathogen interactions. Indeed, the triad of vector-host-pathogen interactions in the skin microenvironment can influence host innate and adaptive responses alike, providing an advantage to the pathogen to establish infection. A better understanding of this “bite site” microenvironment, along with how host and vector local microbiomes immunomodulate responses to pathogens, is required for future vaccines for vector-borne diseases. Microneedle administration of such vaccines may more closely mimic vector deposition of pathogen and saliva into the skin with the added benefit of near painless vaccine delivery. Focusing on the ‘micro’–from microenvironments to microbiomes to microneedles–may yield an improved generation of vector-borne disease vaccines in today’s increasingly complex world.
... One such new vaccine strategy concerns the delivery of vaccines by microscale needles, which, in additional to being painless, more accurately mimic the natural inoculation of the virus by the arthropod vector and thus might elicit better immune activation in the skin (Manning and Cantaert, 2019). In 2018, researchers described the design of a microneedle based on the biology of mosquito mouth parts and the mechanism behind the painless bite, providing an example of innovative and better-designed vaccine delivery systems (Gurera et al., 2018). In comparison to traditional hypodermic needles, which deliver the vaccine into the subcutaneous strata of the skin, transcutaneous microneedle delivery appears to provide the advantage of promoting robust protective skin-resident responses. ...
Article
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Vector-borne diseases are responsible for over a billion infections each year and nearly one million deaths. Mosquito-borne dengue virus, West Nile, Japanese encephalitis, Zika, Chikungunya, and Rift Valley Fever viruses constitute major public health problems in regions with high densities of arthropod vectors. During the initial step of the transmission cycle, vector, host, and virus converge at the bite site, where local immune cells interact with the vector's saliva. Hematophagous mosquito saliva is a mixture of bioactive components known to modulate vertebrate hemostasis, immunity, and inflammation during the insect's feeding process. The capacity of mosquito saliva to modulate the host immune response has been well-studied over the last few decades and has led to the consensus that the presence of saliva is linked to the enhancement of virus transmission, host susceptibility, disease progression, viremia levels, and mortality. We review some of the major aspects of the interactions between mosquito saliva and the host immune response that may be useful for future studies on the control of arboviruses.
... Anecdotally, convenience is a major consideration in the success of biomarker measurement in athletes. Blood sample collection is now possible without traditional venepuncture via micro-filament needles inspired by mosquitoes [34,35], although this technology has not yet been widely deployed. A continuum exists with comprehensive biomarker analysis via venous blood sampling at one extreme, and point-of-care tests for single biomarkers via capillary sampling at the other (lactate is the obvious example in sport, blood glucose is the most common point-of-care test globally). ...
Article
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Blood test data were traditionally confined to the clinic for diagnostic purposes, but are now becoming more routinely used in many professional and elite high-performance settings as a physiological profiling and monitoring tool. A wealth of information based on robust research evidence can be gleaned from blood tests, including: the identification of iron, vitamin or energy deficiency; the identification of oxidative stress and inflammation; and the status of red blood cell populations. Serial blood test data can be used to monitor athletes and make inferences about the efficacy of training interventions, nutritional strategies or indeed the capacity to tolerate training load. Via a profiling and monitoring approach, blood biomarker measurement combined with contextual data has the potential to help athletes avoid injury and illness via adjustments to diet, training load and recovery strategies. Since wide inter-individual variability exists in many biomarkers, clinical population-based reference data can be of limited value in athletes, and statistical methods for longitudinal data are required to identify meaningful changes within an athlete. Data quality is often compromised by poor pre-analytic controls in sport settings. The biotechnology industry is rapidly evolving, providing new technologies and methods, some of which may be well suited to athlete applications in the future. This review provides current perspectives, limitations and recommendations for sports science and sports medicine practitioners using blood profiling and monitoring for nutrition and performance purposes.
... Upon proboscis insertion, a retractable outer cover called labium bends to unravel a fascicle composed of six stylets (14). These include a pair of sharp mandibles and a pair of serrated maxilla that effortlessly pierce through the skin by vibration (15). The hypopharynx, which is enclosed within a sheath-like structure formed by the maxilla and mandibles, releases saliva along the proboscis path to limit bite-sensing, platelet aggregation, bloodclotting, and the immune response (16,17). ...
Article
Mosquito blood-feeding behavior is a key determinant of the epidemiology of dengue viruses (DENV), the most-prevalent mosquito-borne viruses. However, despite its importance, how DENV infection influences mosquito blood-feeding and, consequently, transmission remains unclear. Here, we developed a high-resolution, video-based assay to observe the blood-feeding behavior of Aedes aegypti mosquitoes on mice. We then applied multivariate analysis on the high-throughput, unbiased data generated from the assay to ordinate behavioral parameters into complex behaviors. We showed that DENV infection increases mosquito attraction to the host and hinders its biting efficiency, the latter resulting in the infected mosquitoes biting more to reach similar blood repletion as uninfected mosquitoes. To examine how increased biting influences DENV transmission to the host, we established an in vivo transmission model with immuno-competent mice and demonstrated that successive short probes result in multiple transmissions. Finally, to determine how DENV-induced alterations of host-seeking and biting behaviors influence dengue epidemiology, we integrated the behavioral data within a mathematical model. We calculated that the number of infected hosts per infected mosquito, as determined by the reproduction rate, tripled when mosquito behavior was influenced by DENV infection. Taken together, this multidisciplinary study details how DENV infection modulates mosquito blood-feeding behavior to increase vector capacity, proportionally aggravating DENV epidemiology. By elucidating the contribution of mosquito behavioral alterations on DENV transmission to the host, these results will inform epidemiological modeling to tailor improved interventions against dengue.
... Most biological structures having the ability to penetrate through a hard substrate (like spider fang, scorpion stinger, parasitoid ovipositor 14 etc.) have a tip with higher stiffness. But, in our study of mosquito labrum 15 , the nanomechanical properties revealed that the tip of the labrum has the least amount of hardness. It is believed that because of the soft and compliant tip, lesser pain is experienced during mosquito piercing. ...
Article
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In order to design a painless and mechanically durable micro syringe-needle system for biomedical applications, the study of insect stingers is of interest because of their elegant structures and functionalities. In the present work, the structure, mechanical properties and the mechanical behavior during insertion of wasp and honeybee stingers have been investigated. The non-invasive imaging tool, micro-computed tomography has been employed to reveal the 3D-structures of wasp and honeybee stingers. A quasi-static nanoindentation instrument was used to measure the nanomechanical properties. Both wasp and honeybee stingers have graded mechanical properties, decreasing along their longitudinal direction starting from the base. The computed tomography images and the measured material properties from nanoindentation were fed into a computational framework to determine the mechanical behavior of the stingers during penetration. The computation results predicted the penetration angle of +10o for the wasp stinger and -6o for the honeybee stinger, which mimics the practical insertion mechanism of both stingers. Based on this understanding, a wasp and honeybee stringer inspired micro syringe-needle design has also been proposed.
... The measured location and load-depth curves are shown in Figure S7C. The elastic modulus of the proboscis can be achieved by the initial part of the recovery curve [27]. ...
Article
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Garments treated with chemical insecticides are commonly used to prevent mosquito bites. Resistance to insecticides, however, is threatening the efficacy of this technology, and people are increasingly concerned about the potential health impacts of wearing insecticide-treated clothing. Here, we report a mathematical model for fabric barriers that resist bites from Aedes aegypti mosquitoes based on textile physical structure and no insecticides. The model was derived from mosquito morphometrics and analysis of mosquito biting behavior. Woven filter fabrics, precision polypropylene plates, and knitted fabrics were used for model validation. Then, based on the model predictions, prototype knitted textiles and garments were developed that prevented mosquito biting, and comfort testing showed the garments to possess superior thermophysiological properties. Our fabrics provided a three-times greater bite resistance than the insecticide-treated cloth. Our predictive model can be used to develop additional textiles in the future for garments that are highly bite resistant to mosquitoes.
... The activities of mosquitoes in the ecosystem are as sophisticated and specialized as that of any other creature, and indeed more complex than many. The study of mosquito biology may reveal biochemical, anatomical and behavioural secrets that may not only enrich our understanding of nature but also become a source of bioinspiration in future sciences and technologies, from the design of pain-free microneedles (Gurera et al., 2018) to algorithms for f lying drones (Nakata et al., 2020). Critically, the overwhelming majority of insects that fall within the Culicidae do not pose a threat to human health or comfort, so caution must be exercised when discussing "mosquitoes", generically, as carriers of disease. ...
Chapter
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https://www.taylorfrancis.com/books/oa-edit/10.4324/9781003056034/mosquitopia-marcus-hall-dan-tam%C3%AFr Mosquitoes are one of the most intensely studied creatures on the planet. Their role in disease transmission and nuisance biting makes them worthy of such attention. There are over 3,500 species of mosquito on Earth and they are found on every continent except Antarctica. Yet, from this great diversity, only a small handful can carry the pathogens that cause disease and it is these species which have been studied most intensely. For the purposes of public health, this substantial body of research has helped us to understand mosquito-borne disease transmission and informed the development of mosquito- and disease-control methods. But parallel to this, a fascinating and complex biology has been revealed, showing the mosquito’s incredible and unusual behavioural, anatomical and physiological traits. This chapter will explore some of the unique aspects of mosquito biology and ecology, drawn from the ever-growing body of research on the most medically important species, and highlight the sophisticated adaptations of mosquitoes to their ecological niche.
... A jagged-shaped, vibrated microneedle made from PLA was presented in [73]. Jagged-shaped vibrated microneedles that consist of multiple parallel segments in a number of other studies, made from PLA [74], silicon [75], silicon with a biocompatible coating [76], photocurable epoxy resin [77], ceramic [78], and a frequency-dependent viscoelastic material [79]. Smooth-surface vibrated microneedles made from silicon [58] or titanium for a micro pumping device are presented in a number of other studies [59,[80][81][82]. ...
Article
Insects are important agents in ecosystems. Their diverseness and developed coping mechanisms also make them interesting for direct application and as a source of inspiration in medical engineering. We summarized the main contribution of insects in biomedical applications. Medical centers in North America, the United Kingdom, and Europe use fly larvae for maggot therapy to remove necrotic tissue, decrease infection risk, and improve wound healing. Ant mandibles are used as a suturing technique by African tribes and as sources of inspiration for surgical clamps. Both the mosquito fascicle and the wasp ovipositor are sources of inspiration for the design of medical needles. Herein, a new research field called “entomomedical engineering,” is proposed. We define entomomedical engineering as the branch of engineering that uses insects either directly or as a source of inspiration to design and develop medical treatments or instruments. In addition, we want to emphasize the importance of preserving insects because of their function in the ecosystem, medicine, and medical engineering.
... Because of this, repellency is evaluated by comparing the proportions of blood-fed mosquitoes on treated vs untreated fabric sleeves. A probing female mosquito first injects saliva into a host to numb the local area before finding and feeding on blood (Gurera et al., 2018). This means probing females who do not take a blood meal may nonetheless inject allergens and, if present, pathogens into a 12. Human subject studies of arthropod repellent efficacy, at the interface of science, ethics, and regulatory oversight Increased use of pesticides worldwide drives the evolution of resistance in arthropod populations including those that focus on human hosts. ...
Chapter
In this chapter, we describe considerations for the design of experiments to measure the protective efficacy of bite prevention tools against mosquito vectors. The chapter focuses on the evaluation of spatial repellents (specifically volatile pyrethroids) and topical repellents under semifield conditions including a description of the semifield system and experimental huts used to simulate outdoor and indoor use settings, respectively. We also explain the preparation needed for conducting an experiment in these bioassays to maximise data reproducibility as well as the limitations of the experimental systems. Bite prevention technologies are ultimately designed to prevent the transmission of pathogens by inhibiting bites and in some cases killing the vector. We explain the primary outcomes used to measure the efficacy of bite prevention tools, analysis, and data interpretation. We also describe the relationship between data collected in the semifield and the field setting. The chapter ends with a brief description of how these endpoints can be used in mathematical modeling to simulate the expected public health outcome when bite prevention tools are implemented alone or in combination with other vector control tools for the prevention of vector-borne disease.
... Because of this, repellency is evaluated by comparing the proportions of blood-fed mosquitoes on treated vs untreated fabric sleeves. A probing female mosquito first injects saliva into a host to numb the local area before finding and feeding on blood (Gurera et al., 2018). This means probing females who do not take a blood meal may nonetheless inject allergens and, if present, pathogens into a 12. Human subject studies of arthropod repellent efficacy, at the interface of science, ethics, and regulatory oversight Increased use of pesticides worldwide drives the evolution of resistance in arthropod populations including those that focus on human hosts. ...
Chapter
The chapter discusses the importance of ticks in public health and the extent of threats posed by tick-borne diseases to the wellbeing of humans. The history of tick control efforts highlights various developments over the years from monitoring tick populations to the development and use of tick repellents and control strategies. Different evaluation techniques and procedures used for spatial and topical arthropod repellents are described and discussed. This chapter also includes and summarizes laboratory bioassays, field methodologies, impregnated and sprayed fabric evaluation methodologies, their efficacy determination, the challenges encountered by the arthropod repellents used, evaluations, and recommendations.
Chapter
This chapter deals with smart devices, which were developed on the basis of certain living organisms having unique functions. These include the razor clam whose mode of digging inspired the development of burrowing RoboClams, and various novel sensors such as bioinspired underwater pressure sensors (Notonecta sp.), crack‐based strain sensors (lyriform slit organs of spiders), and actuators mimicking the ice plant seed capsules. Ideas for collecting water from dew and fog have come from studies on organisms which demonstrate four key steps: condensation, coalescence, transportation, and absorption. Such organisms include the Namib Desert Beetle, spider's webs, and minimization of water loss by cacti such as Opuntia microdasys. Ladybirds have wings whose collapse is akin to origami; the ladybird integrates structural stability and deformability which could be applied to space‐deployable structures. The chapter also highlights the painless bites of mosquitoes in contrast to the painful injection needles.
Article
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Chapter
Some 10 million different species of animals and plants are known to exist on earth. Of which, arthropods make up the largest category with roughly 5 million species. The word, arthropods, is derived from two Greek words: arthron (joint) + podos (foot), meaning jointed-feet. These are spineless animals with segmented bodies, paired and jointed legs, exoskeletons, and bilateral symmetry. Arthropods, being one of the major class of animals, create medical problems. They attack other organisms, cause allergic reactions, release toxins and venoms, and may even cause death.
Chapter
People have literally had skin in the game from the beginning of arthropod repellent science more than a century ago. However, formal ethical guidance for human subject repellent studies appeared much more recently, as regulatory agencies that require human data have adopted biomedical standards. The 2005 US EPA Human Studies Rule inaugurated a modern chapter in arthropod repellent development, in which the augmented demands at the intersection of scientific rigor and subject protection have escalated study costs and added challenging strategic quandaries to the pursuit of improved repellents. Risk concerns have likewise led to reliance on carbon dioxide trap counts rather than human subjects for area repellent studies and have fueled a move toward arm-in-cage studies to replace field testing in the European Union. However, neither traps nor arm-in-cage tests necessarily replicate human subject field outcomes, suggesting that uncritical regulatory reliance on surrogate hosts and laboratory systems may risk data relevance while also hampering the development of products that perform better under actual conditions of use. Other repellent modalities, like treated fabrics, will also benefit from methods that more clearly show modes of action and protection from pathogens. While the modern regulatory environment has likely slowed development of new repellent products, efforts toward harmonization among regulatory agencies may increase efficiencies and expedite international commercialization. The coalescence of a more advanced regulatory platform may facilitate the development of new technologies for personal-use protection from arthropods, with better linkages to integrated public health management of disease transmission and pesticide resistance.
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Abstarct Wound healing is the regenerative process of original skin structure after destructing by different damage sources. Due to their transdermal delivery capability and high specific surface area, microneedles arrays (MAs) have been recognized as encouraging biomaterials for wound healing. In this review, we have outlined the engineered MAs used for tissue regeneration and wound healing. Engineered MAs was first classified by design methodologies such as bionic design, intelligent-responsive design, actively-triggered design, matrix materials innovation, and composite smart design. Then, the MAs were divided into two categories based on the different loading substances: drug-loaded MAs and living component-loaded MAs. Finally, we have summed up the important elements of the preceding discussions and forecasted their future evolution.
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To measure nanomechanical properties of surface layers of bulk materials and thin films, depth-sensing nanoindentation measurement techniques are used commonly. The nanoindentation apparatus continuously monitors the load and the position of the indenter relative to the surface of the specimen (depth of an indent or displacement) during the indentation process. Indentation experiments can be performed at a penetration depth of as low as about 5 nm. This paper presents an overview of various nanoindentation techniques, various measurement options, and data analysis. Data on elastic–plastic deformation behavior, hardness, elastic modulus, scratch resistance, film-substrate adhesion, residual stresses, time-dependent creep and relaxation properties, fracture toughness, and fatigue are presented.
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Although mosquitoes (Diptera: Culicidae) are important disease vectors, information on their biodiversity in Mauritania is scarce and very dispersed in the literature. Data from the scientific literature gathered in the country from 1948 to 2016 were collected and analyzed. Overall 51 culicid species comprising 17 Anopheles spp., 14 Aedes spp., 18 Culex spp. and two Mansonia spp. have been described in Mauritania among which Anopheles arabiensis, Aedes vexans, Culex poicilipes and Culex antennatus are of epidemiological significance. Anopheles arabiensis is widely distributed throughout the country and its geographic distribution has increased northwards in recent years, shifting its northern limit form 17°32′N in the 1960s to 18°47′N today. Its presence in the central region of Tagant highlights the great ecological plasticity of the species. Conversely, the distribution of Anopheles gambiae (s.s.) and Anopheles melas has shrunk compared to that of the 1960s. Anopheles rhodesiensis and An. d’thali are mainly confined in the mountainous areas (alt. 200–700 m), whereas Anopheles pharoensis is widely distributed in the Senegal River basin. Culex poicilipes and Cx. antenattus were naturally found infected with Rift valley fever virus in central and northern Mauritania following the Rift valley outbreaks of 1998 and 2012. Recently, Ae. aegypti emerged in Nouakchott and is probably responsible for dengue fever episodes of 2015. This paper provides a concise and up-to-date overview of the existing literature on mosquito species known to occur in Mauritania and highlights areas where future studies should fill a gap in knowledge about vector biodiversity. It aims to help ongoing and future research on mosquitoes particularly in the field of medical entomology to inform evidence-based decision-making for vector control and management strategies.
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Anopheles gambiae is a major vector of malaria and lymphatic filariasis. The arthropod-host interactions occurring at the skin interface are complex and dynamic. We used a global approach to describe the interaction between the mosquito (infected or uninfected) and the skin of mammals during blood feeding. Intravital video microscopy was used to characterize several features during blood feeding. The deposition and movement of Plasmodium berghei sporozoites in the dermis were also observed. We also used histological techniques to analyze the impact of infected and uninfected feedings on the skin cell response in naive mice. The mouthparts were highly mobile within the skin during the probing phase. Probing time increased with mosquito age, with possible effects on pathogen transmission. Repletion was achieved by capillary feeding. The presence of sporozoites in the salivary glands modified the behavior of the mosquitoes, with infected females tending to probe more than uninfected females (86% versus 44%). A white area around the tip of the proboscis was observed when the mosquitoes fed on blood from the vessels of mice immunized with saliva. Mosquito feedings elicited an acute inflammatory response in naive mice that peaked three hours after the bite. Polynuclear and mast cells were associated with saliva deposits. We describe the first visualization of saliva in the skin by immunohistochemistry (IHC) with antibodies directed against saliva. Both saliva deposits and sporozoites were detected in the skin for up to 18 h after the bite. This study, in which we visualized the probing and engorgement phases of Anopheles gambiae blood meals, provides precise information about the behavior of the insect as a function of its infection status and the presence or absence of anti-saliva antibodies. It also provides insight into the possible consequences of the inflammatory reaction for blood feeding and pathogen transmission.
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The diversity of life is one of the most striking aspects of our planet; hence knowing how many species inhabit Earth is among the most fundamental questions in science. Yet the answer to this question remains enigmatic, as efforts to sample the world's biodiversity to date have been limited and thus have precluded direct quantification of global species richness, and because indirect estimates rely on assumptions that have proven highly controversial. Here we show that the higher taxonomic classification of species (i.e., the assignment of species to phylum, class, order, family, and genus) follows a consistent and predictable pattern from which the total number of species in a taxonomic group can be estimated. This approach was validated against well-known taxa, and when applied to all domains of life, it predicts ~8.7 million (± 1.3 million SE) eukaryotic species globally, of which ~2.2 million (± 0.18 million SE) are marine. In spite of 250 years of taxonomic classification and over 1.2 million species already catalogued in a central database, our results suggest that some 86% of existing species on Earth and 91% of species in the ocean still await description. Renewed interest in further exploration and taxonomy is required if this significant gap in our knowledge of life on Earth is to be closed.
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The mechanics of a fascicle insertion into the skin by a mosquito of the type aedes aegypti has been studied experimentally using high-speed video (HSV) imaging, and analytically using a mathematical model. The fascicle is a polymeric microneedle composed of a ductile material, chitin. It has been proposed that the mosquito applies a non-conservative follower force component in addition to the Euler compressive load in order to prevent buckling and penetrate the skin. In addition, the protective sheath surrounding the fascicle (labium) provides lateral support during insertion. The mechanics model presented approximates the fascicle as a slender column supported on an elastic foundation (labium) subjected to non-conservative (Beck) and conservative Euler loads simultaneously at the end. Results show that the lateral support of the fascicle provided by the labium is essential for successful penetration by increasing the critical buckling load by a factor of 5. The non-conservative follower force application increases the buckling load by an additional 20% and may or may not be necessary for successful penetration. Experimental results showing the importance of the labium have been cited to validate the model predictions, in addition to the video observations presented in this work. This understanding may be useful in designing painless needle insertion systems as opposed to miniaturized hypodermic needles.
Article
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Malaria is estimated to cause 0.7 to 2.7 million deaths per year, but the actual figures could be substantially higher owing to under-reporting and difficulties in diagnosis. If no new control measures are developed, the malaria death toll is projected to double in the next 20 years. Efforts to control the disease are hampered by drug resistance in the Plasmodium parasites, insecticide resistance in mosquitoes, and the lack of an effective vaccine. Because mosquitoes are obligatory vectors for malaria transmission, the spread of malaria could be curtailed by rendering them incapable of transmitting parasites. Many of the tools required for the genetic manipulation of mosquito competence for malaria transmission have been developed. Foreign genes can now be introduced into the germ line of both culicine and anopheline mosquitoes, and these transgenes can be expressed in a tissue-specific manner. Here we report on the use of such tools to generate transgenic mosquitoes that express antiparasitic genes in their midgut epithelium, thus rendering them inefficient vectors for the disease. These findings have significant implications for the development of new strategies for malaria control.
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Blood-feeding insects, including the malaria mosquito Anopheles gambiae, use highly specialized and sensitive olfactory systems to locate their hosts. This is accomplished by detecting and following plumes of volatile host emissions, which include carbon dioxide (CO2). CO2 is sensed by a population of olfactory sensory neurons in the maxillary palps of mosquitoes and in the antennae of the more genetically tractable fruitfly, Drosophila melanogaster. The molecular identity of the chemosensory CO2 receptor, however, remains unknown. Here we report that CO2-responsive neurons in Drosophila co-express a pair of chemosensory receptors, Gr21a and Gr63a, at both larval and adult life stages. We identify mosquito homologues of Gr21a and Gr63a, GPRGR22 and GPRGR24, and show that these are co-expressed in A. gambiae maxillary palps. We show that Gr21a and Gr63a together are sufficient for olfactory CO2-chemosensation in Drosophila. Ectopic expression of Gr21a and Gr63a together confers CO2 sensitivity on CO2-insensitive olfactory neurons, but neither gustatory receptor alone has this function. Mutant flies lacking Gr63a lose both electrophysiological and behavioural responses to CO2. Knowledge of the molecular identity of the insect olfactory CO2 receptors may spur the development of novel mosquito control strategies designed to take advantage of this unique and critical olfactory pathway. This in turn could bolster the worldwide fight against malaria and other insect-borne diseases.
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Rethinking the relationship between Homo sapiens and Planet Earth in the Anthropocene is fundamental for a sustainable future for humankind. The complex Earth system and planetary boundaries demand new approaches to addressing our current challenges. Bionics, namely learning from the diversity of life for nature-based technical solutions, is an increasingly important component. In this paper, we address the interrelated aspects of the uneven geographic distribution of biodiversity, the issue of the continued erosion of biodiversity translating into a loss of the “living prototypes” for bionics, the relationship between bionics and biodiversity and the North-south gradient in institutional capacity related to biodiversity and bionics-related areas. World maps illustrating these points are included. In particular, we discuss historical aspects and complex terminological issues within bionics or rather bionics-related disciplines, the role of evolution and biodiversity as contributors to the fabric of bionics and the contribution of bionics to the attainment of sustainable development. The history of bionic ideas and the confusing terminologies associated with them (the term bionic was coined in 1901) are discussed with regard to research, design and marketing. Bionics or Biomimetics, as we understand it today, dates back to the period between 1800 and 1925 and its proponents Alessandro Volta (electric battery), Otto Lilienthal (flying machine), and Raoul Francé (concepts). It was virtually reinvented under the strong influence of cybernetics in the 1960s by H. v. Foerster and W. McCulloch. The term biomimetics arose simultaneously with a slightly different connotation. “Bioinspiration” is a convenient modern overarching term that embraces everything from bionics and biotechnology to bioinspired fashion design. Today, marketing strategies play a crucial role in product placement within an increasingly competitive economy. The majority of so-called “biomimetic” products, however, only pretend to have a bionic origin or function; we have introduced the term “parabionic” for such products. Life arose almost four billion years ago. Today’s relevant living prototypes for bionics have a history of more than one billion years of evolution, in essence a process of “technical optimization” governed by mutation and selection. In one specific example, we provide evidence that superhydrophobicity, an important biomimetic feature, has been in existence since at least the Paleozoic period, the time when life conquered land. Bionics might be a major contributor to future nature-based technological solutions and innovations, thus addressing some of humankind’s most pressing issues. Bionics and related fields may become a major component of the current “great transformation” that humanity is experiencing on its trajectory towards sustainable development.
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Transdermal drug delivery offers a number of advantages for the patient, due to not only its noninvasive and convenient nature, but also factors such as avoidance of first-pass metabolism and prevention of gastrointestinal degradation. It has been demonstrated that microneedles can increase the number of compounds amenable to transdermal delivery by penetrating the skin's protective barrier, the stratum corneum, creating a pathway for drug permeation to the dermal tissue below. Microneedles have been extensively investigated for drug and vaccine delivery. The different types of microneedle arrays and their delivery capabilities are discussed in terms of drugs, including biopharmaceutics and vaccines. Patient usage and effects on the skin are also considered. Microneedle research and development are now at the stage where commercialization is a viable possibility. A number of long-term safety questions relating to patient usage will need to be addressed moving forward. Regulatory guidance is awaited to direct the scale-up of the manufacturing process alongside provision of clearer patient instruction for safe and effective use of microneedle devices.
Article
Special internal structures of the cuticle of a beetle have multifunctionality including self-protection and attraction of mates using structural coloration, and being lightweight with high strength, which can protect the body and membranous hindwings. Special optical properties were found in the black spots region (BSR) of the cuticle of the multicolored Asian lady beetle (Harmonia axyridis). Both the BSR and the orange region (OR) have alternating layers of chitin and melanoprotein, as detected using field emission scanning electron microscopy (FESEM). However, a parallel wavy line structure was found in the BSR via laser scanning confocal microscopy (LSCM). This special structural color may arise via a diffraction grating mechanism. To explore the relationship between the material and its optical properties, the dynamic nanoindentation approach (nano-DMA) was used. The viscoelastic properties of the cuticle were assessed including the storage modulus (E′), loss modulus (E′′) and loss tangent (tanδ), in the differently colored zones. The extent of protein cross-linking affects the cuticle's mechanical properties. We then demonstrated the applicability of a power-law frequency dependence analysis of E′ and tan δ. Furthermore, the frequency exponent of n and tan δ were discussed in relation to the BSR and OR. A lower wavelength of maximum reflectance was found in the BSR that had little frequency dependence on n and a larger tan δ value related to its extent of protein cross-linking. This is contrary to the results obtained in the OR. The results will help in designing lightweight, high strength, and color-changing micro air vehicles (MAVs).
Article
In this chapter, the current progress on nanoindentation measurement of dental hard tissues is summarized. With the help of nanoindentation techniques, it is possible to measure the mechanical properties of small volumes of dental hard tissues at the micro- and nano-level with respect to their unique microstructures, namely the rod unit of the enamel and tubule structure of dentin. The results indicate that the microstructure and organic components regulate the mechanical behaviour of these natural biocomposites to a great extent. Furthermore, application of nanoindentation to the investigation of diseased or defective states of tooth tissues, dental treatments and dental materials is also introduced and discussed. © 2011 by Pan Stanford Publishing Pte. Ltd. All rights reserved.
Article
The great importance of mosquitoes lies in their role as transmitters of pathogens and parasites, and in their use as experimental animals well suited to laboratory investigations into aspects of biochemistry, physiology and behaviour. The largest part of this latest volume of The Biology of Mosquitoes concerns interactions between mosquitoes and viruses and the transmission of arboviruses to their vertebrate hosts, while the remainder concerns symbiotic interactions between mosquitoes and bacteria. The introduction provides a timely review of the first major development in mosquito taxonomy for several decades. Further chapters describe the interactions between mosquitoes and the viruses that infect them, the transmission and epidemiology of seven very important arboviruses, and the biology of bacteria that are important control agents or of great biological interest. Like the earlier volumes, Volume 3 combines recent information with earlier important findings from field and laboratory to provide the broadest coverage available on the subject.
Article
Preface Part A. The Head, Ingestion, Utilization and Distribuiton of Food: 1. Head 2. Mouthparts and feeding 3. Alimentary canal, digestion and absorption 4. Nutrition 5. Circulatory system, blood and immune system 6. Fat body Part B. The Thorax, Muscles and Locomotion: 7. Thorax 8. Legs and locomotion 9. Wings and flight 10. Muscles Part C. The Abdomen, Reproductive System and Development: 11. Abdomen 12. Reproductive system: male 13. Reproductive system: female 14. The egg and embryology 15. Postembryonic development Part D. The Integument, Gas Exchange and Homeostasis: 16. Integument 17. Gaseous exchange 18. Excretion and salt and water regulation 19. Thermal relations Part E. Communication: I. Physiological Co-ordination within the Insects: 20. Nervous system 21. Endocrine System II. Perception of the Environment: 22. Visual system 23. Mechanoreception 24. Chemoreception III. Communication with other Organisms: 25. Color and light production 26. Mechanical communication: sound production 27. Chemical communication: pheromones and chemicals with interspecific significance Species index Subject index.
Article
The piercing mouthparts of three species of mosquitoes were examined with a stereoscan scanning electron microscope. The structures observed are discussed in relation to existing morphological studies. Two pairs of peg-like organs were seen at the tip of the labrum and sensory-like structures measuring approximately 1.2 μ were shown at the tip of the hypopharynx of all species. Differences were observed in the numbers of maxillary teeth of different species. The stylets of Wyeomyia smithii appear functional despite the belief that this species does not take a blood meal.
Article
A biological and dry-style superhydrophobic antifogging properties of mosquito C. pipines compound eyes with clear vision were studied and the artificial compound eyes were fabricated by using soft lithography to investigate the effects of micro- and nanostructures on the surface hydrophobicity. The mosquito eye compound structure composed of microscale hemisphere acted as individual sensory units ommatidia and the hierarchical micro- and nanostructures were considered as heterogeneous curved surfaces composed of air and solids. The mosquito eyes with superhydrophobic characters are found to provide antifogging for microscale fog drops and the tiny drops are tapped. The optical photography of an artificial compound eye shows that the PDMS hemisphere has uniform diameters and surface of each PDMS micro-hemisphere structures enhances the water-resistant property of the surface.
Article
Dragonfly wings possess great stability and high load-bearing capacity during flapping flight, glide, and hover. Scientists have been intrigued by them and have carried out research for biomimetic applications. Relative to the large number of works on its flight aerodynamics, few researchers have focused on the insect wing structure and its mechanical properties. The wings of dragonflies are mainly composed of veins and membranes, a typical nanocomposite material. The veins and membranes have a complex design within the wing that give rise to whole-wing characteristics which result in dragonflies being supremely versatile, maneuverable fliers. The wing structure, especially corrugation, on dragonflies is believed to enhance aerodynamic performance. The mechanical properties of dragonfly wings need to be understood in order to perform simulated models. This paper focuses on the effects of structure, mechanical properties, and morphology of dragonfly wings on their flyability, followed by the implications in fabrication and modeling.
Article
An indentation system is developed to directly apply loads ranging from 1μN to 10 mN and to make load - displacement measurements with subnanometre indentation depth capability. This system is used here in conjunction with a commercial atomic force microscope to provide in-situ imaging. A three-sided pyramidal (Berkovich) diamond tip has been used to obtain a load - displacement curve with residual depths of the order of 1 nm. The load - displacement data have been used to obtain indentation hardness and Young's modulus of elasticity for single-crystal silicon and GaAs. Hardness on the nanoscales is found to be higher than that on the microscale. Ceramics exhibit significant plasticity and creep on the nanoscale.
Article
The mouthparts of female mosquitoes have evolved to form a special proboscis, a natural biomicroelectromechanical system (BMEMS), which is used for painlessly penetrating human skin and sucking blood. Scanning electron microscope observations show that the mosquito proboscis consists of a small bundle of long, tapering, and feeding stylets that are collectively called the fascicle, and a large scaly outer lower lip called the labium. During blood feeding, only the fascicle penetrates into the skin while the labium buckles back to remain on the surface of the skin. Here, we measured the dynamic force of penetration of the fascicle into human skin to reveal the mechanical principle underlying the painless process of penetration. High-speed video observations of movements associated with insertion of the fascicle indicate that the "smart" mosquito does not directly pierce its victim's skin with the fascicle. Instead, it uses the two maxillas as variable frequency microsaws with nanosharp teeth to advance into the skin tissue. This elegant BMEMS enables the mosquito to insert its feeding fascicle into human skin using an exceedingly small force (average of 16.5 μN).
Article
Within the Diptera and outside the suborder Brachycera, the blood-feeding habit occurred at least twice, producing the present day sand flies, and the Culicomorpha, including the mosquitoes (Culicidae), black flies (Simulidae), biting midges (Ceratopogonidae) and frog feeding flies (Corethrellidae). Alternatives to this scenario are also discussed. Successful blood-feeding requires adaptations to antagonize the vertebrate's mechanisms of blood clotting, platelet aggregation, vasoconstriction, pain and itching, which are triggered by tissue destruction and immune reactions to insect products. Saliva of these insects provides a complex pharmacological armamentarium to block these vertebrate reactions. With the advent of transcriptomics, the sialomes (from the Greek word sialo = saliva) of at least two species of each of these families have been studied (except for the frog feeders), allowing an insight into the diverse pathways leading to today's salivary composition within the Culicomorpha, having the sand flies as an outgroup. This review catalogs 1288 salivary proteins in 10 generic classes comprising over 150 different protein families, most of which we have no functional knowledge. These proteins and many sequence comparisons are displayed in a hyperlinked spreadsheet that hopefully will stimulate and facilitate the task of functional characterization of these proteins, and their possible use as novel pharmacological agents and epidemiological markers of insect vector exposure.
Article
Unfed 2- to 5-day-old females of different species of Florida mosquitoes were fed ad lib. a meal of chicken blood to repletion and analyzed for weights and calorie intake, survival, and accumulation and depletion of energy reserves. Females ingested blood meals with wet weights of 2.5 to 4 times greater than their own wet weights and dry weights of 1.2 to 1.7 times greater than their own dry weights. Efficiency of blood ingested for survival was highest in Aedes aegypti (84.5 hr/cal.) followed by Aedes taeniorhynchus (68.5 hr/cal.) and A. sollicitans, Anopheles quadrimaculatus and Psorophora confinnis (44.0 to 48.4 hr/cal.). Glycogen and triglycerides accumulated after blood ingestion, reaching maximum values within 24 to 72 hr before decreasing to stable values in the next 24 to 96 hr. Part of the energy reserves synthesized from blood prolonged survival of unfed females from 3 days in An. quadrimaculatus to 8 days in A. taeniorhynchus more than the starved females, and the remainder of the reserves was stored in yolk of matured oocytes. It is concluded that a blood meal provides sufficient reserves to enable the species investigated to survive long enough to produce a batch of eggs.
Article
This review of the history of medical entomology commemorates the centenary of the historic discovery in 1877 by Patrick Manson in China that Culex pipiens fatigans was a vector of bancroftian filariasis. This discovery, published in 1878, provided the first real evidence that a disease of man underwent obligatory development in an insect, and is, therefore, justifiably regarded as the Birth of Medical Entomology. Although medical entomology as a science began in 1877, much earlier theories and speculations are found in the histories of many lands concerning the possibility that insects were somehow associated with the spread of disease. Accounts of some of these early concepts dating from prebiblical and biblical times through the Renaissance period of Europe up to about the middle of the 19th century are presented, culminating in a description of the investigations leading to the discovery of mosquito-borne filariasis. Medical entomology flourished from the late 1890ʼs to about the mid-1930's when new discoveries of the role of arthropods in disease transmission came in quick succession. This review highlights and traces the development of medical entomology during this period by describing the investigations that led to the discoveries that arthropods were vectors of malaria, Texas fever, animal and human trypanosomiasis, plague and yellow fever.
Article
Extracellular microelectrode recordings were made of the responses of thin-walled sensillae on the antennae and maxillary palpi of female Aedes aegypti to water vapour and carbon dioxide. One type of antennal sensilla basiconica responded to water vapour with an increase in the action potential rate and was capable of detecting a sudden increase of 2 per cent in the relative humidity. One neuron in another type of sensilla basiconica on the maxillary palpi showed a logarithmic sensitivity to sedden increases in carbon dioxide concentration from below 0·01% to a saturation level of 0·05 to 0·5%.
Article
We evaluated the potential for several North American mosquito species to transmit the newly introduced West Nile (WN) virus. Mosquitoes collected in the New York City metropolitan area during the recent WN virus outbreak, at the Assateague Island Wildlife Refuge, VA, or from established colonies were allowed to feed on chickens infected with WN virus isolated from a crow that died during the 1999 outbreak. These mosquitoes were tested approximately 2 wk later to determine infection, dissemination, and transmission rates. Aedes albopictus (Skuse), Aedes atropalpus (Coquillett), and Aedes japonicus (Theobald) were highly susceptible to infection, and nearly all individuals with a disseminated infection transmitted virus by bite. Culex pipiens L. and Aedes sollicitans (Walker) were moderately susceptible. In contrast, Aedes vexans (Meigen), Aedes aegypti (L.), and Aedes taeniorhynchus (Wiedemann) were relatively refractory to infection, but individual mosquitoes inoculated with WN virus did transmit virus by bite. Infected female Cx. pipiens transmitted WN virus to one of 1,618 F1 progeny, indicating the potential for vertical transmission of this virus. In addition to laboratory vector competence, host-feeding preferences, relative abundance, and season of activity also determine the role that these species could play in transmitting WN virus.
Article
A cDNA coding for a protein with significant similarity to adenosine deaminase (ADA) was found while randomly sequencing a cDNA library constructed from salivary gland extracts of adult female Culex quinquefasciatus. Prompted by this result, we found high ADA activities in two culicine mosquitoes, Culex quinquefasciatus and Aedes aegypti, but not in the anopheline Anopheles gambiae. Homogenates from Culex quinquefasciatus also have an AMP deaminase activity that is three times greater than the ADA activity, whereas in Aedes aegypti the AMP deaminase activity is less than 10% of the ADA activity. Evidence for secretion of ADA during blood feeding by Aedes aegypti includes the presence of ADA activity in warm solutions probed through a membrane by mosquitoes and in serotonin-induced saliva and a statistically significant reduction in the levels of the enzyme in Aedes aegypti following a blood meal. We could not demonstrate, however, that C. quinquefasciatus secrete ADA in their saliva. Male Aedes aegypti and C. quinquefasciatus, which do not feed on blood, have less than 3% of the levels of ADA found in females. We propose that ADA activity in A. aegypti may help blood feeding by removing adenosine, a molecule associated with both the initiation of pain perception and the induction of mast cell degranulation in vertebrates, and by producing inosine, a molecule that potently inhibits the production of inflammatory cytokines. The role of salivary ADA in Culex quinquefasciatus remains unclear.
Article
Landscape and climatic factors regulate distributions of mosquitoes (Diptera: Culicidae) over time and space. The anthropogenic control of mosquito populations is often carried out at a local administrative scale, and it is applied based on the relevant agency's experiential knowledge rather than systematic analysis of spatial and temporal data. To address this shortcoming, a spatial and temporal analysis of landscape and climatic parameters in relation to mosquito populations in Black Hawk County, IA, USA, has been carried out. Adult mosquito sampling took place using CDC light traps from May to August 2003 in representative landscapes. Mosquitoes were identified to species level with Aedes trivittatus (Coquillet) and Aedes vexans (Meigen) dominating the collection totals. The best publicly available spatial data on landscape and demographic attributes were collated and included land cover, human census, soils, floodplain, elevation, wetlands, hydrography, roads, and vegetation indices derived from satellite imagery. Spatial processing was carried out to organize landscape attributes for statistical comparison with abundance data from the potentially important West Nile virus (family Flaviviridae, genus Flavivirus, WNV) vector species Ae. vexans and Ae. trivittatus. Landscape parameters shown to be significantly correlated with mosquito counts included soil hydrological properties, presence in floodplain, wetland areas, and deciduous and bottomland forest cover. Data on temperature and precipitation were used to investigate the climatic influence on the temporal occurrence of mosquito population abundances. Late spring rain provided ample moisture for mosquito development, but low temperatures delayed widespread emergence of Ae. trivittatus and Ae. vexans until June 2003. Landscape and climatic impacts on adult mosquito population distributions were demonstrated, and these results could form the basis for the development of a spatiotemporal modeling framework that would inform anthropogenic mosquito control anld vector-borne disease surveillance. A qualitative discussion concerning Culex pipiens (L.) and Culex restuans Theobald is included.
The Yellowjackets of America North of Mexico
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Why I'd Rather Cuddle with a Shark than a Kissing Bug
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Gates III, W. H. Why I'd Rather Cuddle with a Shark than a Kissing Bug. gatesnotes.com (2016). Available at: https://www.gatesnotes.com/Health/Most-Deadly-Animal-Mosquito-Week-2016.
Entomology for Students of Medicine
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Bugs of the world. (Facts on File
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Fewer species. Nat 347
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Introduction. in Medical and Veterinary Entomology
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Durden, L. A. & Mullen, G. R. Introduction. in Medical and Veterinary Entomology (eds. Mullen, G. R. & Durden, L. A.) 1-12 (Academic Press, 2009).