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Airborne insect particles have been identified as an important cause of respiratory allergies, including allergic asthma and rhinitis. In the literature, the significance of respiratory exposure to insect particles as a cause of occupational allergy has been well-documented. Indeed, many cases of occupational allergy have been reported including allergy to the larvae of flies and moths in anglers and occupationally exposed workers, to grain pests in bakers or other workers handling grains, and to crickets and/or locusts in researchers and workers in aquaculture companies. Furthermore, the prevalence of sensitization to insect allergens is considerably high among patients with asthma and/or rhinitis who are not occupationally exposed to insects, suggesting the clinical relevance of exposure to insects in indoor and outdoor environmental non-occupational settings. Exposure to cockroaches, a well-studied indoor insect, is associated with cockroach sensitization and the development and exacerbation of asthma. Booklice, another common indoor insect, were recently identified as a significant sensitizer of asthmatic patients in Japan and India, and potentially of asthma patients living in warm and humid climates around the world. Lip b 1 was identified as an allergenic protein contributing to the species-specific sensitization to booklice. Moths are considered a significant seasonal outdoor allergen and their allergens are considered to have the highest sensitization rate among Japanese patients. However, other than cockroaches, allergenic insect proteins contributing to sensitization have not been fully characterized to date.

Introduction GSTs are multifunctional enzymes involved in cellular detoxification and present as potent allergens in several sources. Present study investigates allergenic relevance of GST from P. americana and determine its cross reactive potential with other indoor allergen sources. Methods Computational analysis with FASTA and ConSurf webserver was performed to determine potentially cross reactive allergens. Further, Per a 5 gene was cloned in pET 22b+ vector and expressed in E.coli BL21 cells and the rPer a 5 protein was purified using Ni-NTA affinity chromatography. Enzymatic activity of rPer a 5 was assessed using CDNB and cumene hydroperoxide. ELISA and immunoblot were performed using cockroach hypersensitive patient’s sera. Functional activity of rPer a 5 was evaluated by basophil activation test. Inhibition studies were carried out with D. pteronyssinus, A. alternata and C. lunata extracts. Results Per a 5 demonstrates highest sequence similarity with delta class GST of Blattella germanica (94.9%). It also exhibits significant sequence similarity (50–58%) with mite, fungal and helminth allergenic GSTs. ConSurf analysis reveals high degree of evolutionary similarity in N terminal region of Per a 5, especially at GST dimerization interface. The purified rPer a 5 protein resolved at 27 kDa on SDS-PAGE. The rPer a 5 protein exhibits GST activity and possess upto 65% immunoreactivity with cockroach hypersensitive patient’s sera in ELISA and immunoblot. It upregulates expression of CD203c on basophils signifying its biological ability to activate effector cells. rPer a 5 significantly inhibits corresponding GSTs in P. americana, D. pteronyssinus, A. alternata and C. lunata with EC50 values of 15.5 ng. 38.38 ng, 41.4 ng and 61.66 ng, respectively. Conclusion Recombinant delta class GST of P. americana is a clinically relevant allergen showing upto 65% immunoreactivity with hypersensitive patient’s sera. Per a 5 GST allergen showed phylogenetic similarity with dust mite, fungal and birch allergens thereby demonstrating allergen cross reactivity.

Cockroaches and termites (Order: Blattodea) have been the subject of substantial research attention for over a century due, in part, to a subset of them having a strong propensity to cohabitate with humans and their structures. Recent research has led to numerous insights into their behavior, physiology, and ecology, as well as their ability to harbor taxonomically diverse microbial communities within their digestive systems, which include taxa that contribute to host growth and development. Further, recent investigations into the physiological and behavioral adaptations that enable recalcitrant polysaccharide digestion and the maintenance of microbial symbionts in cockroaches and termites suggests that symbionts contribute significantly to nutrient provisioning and processing.

The Blattulidae is an extinct family of cosmopolitan Mesozoic cockroaches with a low generic diversity. Habroblattula laiyangensis sp. nov. from the Lower Cretaceous Laiyang Formation of Shandong Province of China with well-preserved both hind wings is only closely related to the H. drepanoides Wang, Liang & Ren, 2007 from the Early Cretaceous Yixian Formation, sharing the venation pattern, while being significantly smaller, and provides new characteristics of ancient Blattulidae. In addition, H. laiyangensis sp. nov. resembles distribution patterns of a closely related complex of “Piniblattella” yixianensis Gao, Shih & Ren, 2018 with “Mesoblattina” sinica Ping, 1928, suggesting a spatiotemporal paleobioprovincial relation among Laiyang and Yixian formations, former probably representing more warmer southern localities. Laiyangia Grabau, 1923 and Sinoblatta Grabau, 1923 are indigenous to Laiyang and lack analogues also in numerous Cretaceous Mongolian and Russian sites evidencing a degree of isolation.

We report a fossil ootheca of Dictyoptera from mid-Cretaceous Burmese (Myanmar) amber. This ootheca resembles those of extant mantises, particularly Chaeteessa, and it is provisionally identified to Mantodea. Whilst Blattodea (Blattaria and Isoptera, or ‘true’ cockroaches and termites) are ruled out as the owner of this ootheca, Alienoptera and basal Dictyoptera remain possible. This is the first fossil described of the mantis-type ootheca, and also direct evidence of Dictyoptera in Cretaceous.

Blattulidae is an extinct cockroach family which was widely distributed around the world and lasted from Late Triassic to Cretaceous. Here we describe and illustrate the first blattulid genus found in the mid-Cretaceous Burmese amber, Huablattula gen. nov., to accommodate two new species, Huablattula hui sp. nov. and Huablattula jiewenae sp. nov. Most blattulid genera were only described based on inadequate samples, or were based only on nymphs, isolated tegmina, or wings. The well-preserved adult specimens described in this work not only fill a blank in Blattulidae study in Burmese amber, but also advance out knowledge of this family.

Mid-Cretaceous amber from Myanmar, also known as “burmite”, has produced 1013 species of which 693 are Insects. The Mesozoic cockroach record is rich, with thousands of specimens that show diverse ecological adaptations. Cretaceous cockroaches in amber have been reported from Lebanon, Taimyr, New Jersey and France. Cockroaches from Myanmar amber are represented by at least 74 species, of which 14 are formally described. Spinaeblattina with S. myanmarensis gen. et sp. nov. and S. yixianensis comb. n. = Piniblattella yixianensis from the Yixian Formation is along with Cratovitisma the second genus of the Mesoblattinidae known from both amber and sedimentary deposits. Fossil ootheca are rare with 6 specimens reported so far and the present isolated one, Blattoothecichnus argenteus ichnogen. et ichnosp. nov., is the most ancient, portable, otherwise resembling that of Cryptocercus. Ancient crystals of organic salt, calcium oxalate, forming the ootheca protective layer have been preserved on its surface.

Insects are rich in major nutrients, such as protein and fat. Recently, minor nutrients like vitamins have become the subjects of interest in insects. Hence, this study reports on the development and validation of a method for the determination of vitamin B12 in mealworm (Tenebrio molitor larvae), cricket (Gryllus assimilis), grasshopper (Locusta migratoria) and cockroach (Shelfordella lateralis), using an ultra-high performance liquid chromatography approach with preliminary immunoaffinity chromatography sample preparation. The method was validated regarding linearity, specificity, accuracy and precision, as well as limits of detection/quantification, and was found to be satisfactory for the desired application. Found levels of vitamin B12 were 1.08 µg/100 g for mealworm, 2.88 µg/100 g for cricket, 0.84 µg/100 g for grasshopper, and 13.2 µg/100 g dry weight for cockroach, representing the first validated report on the content of vitamin B12 in edible insects. Observed interferences are likely caused by the presence of pseudovitamin B12.

A new corydiid cockroach, Magniocula apiculata gen. et sp. nov., is described and illustrated based on a well-preserved specimen in Upper Cretaceous Burmese amber. Magniocula is placed in the extant subfamily Euthyrrhaphinae based on the small pubescent body, large clypeus surpassing the distal border of the antennal sockets, and two spines at apex of the front femur. However, this new genus is unique among Euthyrrhaphinae for its holoptic eyes. This is the second corydiid species found in Cretaceous Burmese amber, which highlights the palaeodiversity of the family Corydiidae in the mid-Cretaceous.

Jaburetox (Jbtx) is an insecticidal peptide derived from Canavalia ensiformis urease, whose mechanism of action is not completely elucidated. We employed behavioral, electromyographical and electrophysiological protocols to identify the cellular and molecular targets involved in the Jbtx entomotoxicity in cockroaches and locusts. In Nauphoeta cinerea, Jbtx (32 μg/g) altered the locomotory behaviour inducing a significative decrease in the distance travelled followed by a significant increase in stopped time (52 ± 85 cm and 2573 ± 89 s, p .05, n = 40). Jbtx (8 to 32 μg/g body weight, respectively) also increased the leg and antennae grooming activities (p .05, n = 40, respectively). Jbtx (8 to 16 μg/g) induced a maximum neuromuscular blockade of 80.72% (n = 6, p .05) and was cardiotoxic, decreasing the cockroach heart rate. The electrophysiological profiles of both muscle and nerve of L. migratoria showed that Jbtx (2.5 × 10

In the context of animal aggression, the winner/loser effect is a cross-taxa phenomenon. In the present study, the effect of social contest experience on winning and losing subsequent encounters was investigated in the furious male lobster cockroach, Nauphoeta cinerea. Dominant and subordinate individuals were generated as the result of an encounter between two socially naive males (SNMs); the winner and loser were designated as 1st encounter dominants and 1st encounter subordinates, respectively. With these dominants and subordinates, three experiments were conducted: (I) the original pair met in a re-encounter, (II) the 1st encounter dominants and subordinates were paired with an inexperienced SNM, (III) the 1st encounter dominants and subordinates were paired with an experienced individual of the same rank. Each experiment was conducted at 1 week, 2 weeks, 3 weeks, 4 weeks and 5 weeks after the 1st encounter fight. Juvenile hormone (JH) III titer was monitored in all individuals before and after each subsequent encounter. Our results showed that, in the original pairing and in the pairing with SNMs, the probability that a 1st encounter dominant (or subordinate) would win (or lose) the subsequent encounter fit well with the 95% confidence interval of the theoretical criteria proposed by Begin et al. (1969), indicating the existence of the winning/losing effect. However, this effect was inconsistent along the five-week observation period. For all 1st encounter dominants, at each week after the 1st encounter, the before subsequent encounter JH III titers distribution was significantly different from that on the 1st encounter day; the distributions of before subsequent encounter JH III titers could be further clustered into two groups, the higher JH III group and the lower JH III group, which were significantly correlated with subsequent winning and losing, respectively. For the 1st encounter subordinates, the distributions of before subsequent encounter JH III titers were not significantly different from that of SNMs, but the titer distributions were significantly shifted to a higher level compared to the 1st encounter day. Compared with before subsequent encounter, the after subsequent encounter hemolymph JH III level was significantly increased in winners and significantly decreased in losers. From these data, we propose that instability of the winner and loser effects may occur due to physiological costs and recovery; this instability may partly explain why the social hierarchy is unstable in this cockroach species.

Here we describe a new corydiid cockroach, Nodosigalea burmanica gen. et sp. nov., from the middle Cretaceous Burmese amber. The well-preserved specimens exhibit a typical habitus of Corydiidae, and are characterized by nodulous pronotum, distinct wing venation and unique tarsi, the hind ones of which have different ventral structures from the fore- and midlegs. The combination of adhesive fore- and midtarsi and propulsive hindtarsi suggests a particular life style of the new genus. The phylogenetic position of the new genus within Corydiidae, however, is uncertain.

Toxic organophosphates (OPs) are widely used by the man to manage crops and household insects. Here we used the cockroach, Nauphoeta cinerea, as an alternative model to study the effect of chlorpyrifos (CPF) on the acetylcholinesterase (AChE) and its reactivation by pralidoxime (2-PAM). The main objective was to determine the suitability of N. cinerea as a high-throughput animal model to study the behavioral and biochemical effects of CPF. Here, in silico approaches were also used to further refine the interaction of both CPF and 2-PAM with different sources of AChEs (human, mouse, fruit fly, and cockroach). Since data about the distribution of chemicals in N. cinerea are not available in the literature, we used methylene blue as an “indirect indicator” of CPF and 2-PAM distribution in cockroaches. After 40 min of administration, methylene blue was detected in the head region of cockroaches. A single injection of CPF (3.4 nmol in 10 µL) in the dorsal region of N. cinerea caused typical signs of OP poisoning (from 30 to 60 min after CPF injection). The administration of 2-PAM (10 min after the CPF) was able to reverse the behavioral and biochemical (AChE activity) changes induced by CPF. The in silico docking simulations between the cockroach AChE and the chemicals (CPF and 2-PAM) provided insight into the binding pose and molecular interactions of the chemicals with AChE structure. Thus, the N. cinerea can be a potential experimental model and reliable for researchers because the treatments with CPF and 2-PAM on this species had the same pattern as studies realized in the mammalian models.

Pyrethrin I, pyrethrin II, cinerin I, cinerin II, jasmolin I and jasmolin II are six closely related insecticidal active esters, known as pyrethrins, found in the pyrethrum extract from the dry flowers of Tanacetum cinerariifolium. The chemical structures of the six compounds differ only in the terminal moieties at the acid and alcohol ends, but the compounds' in vivo toxicities are substantially different. Pyrethrins are lead compounds for pyrethroids, a large family of synthetic insecticides that alter nerve functions by prolonging the opening of voltage-gated sodium channels. However, data on the mechanism of action of natural pyrethrins are very limited. In this study, we examined the actions of all six pyrethrins on cockroach sodium channels expressed in Xenopus oocytes. Although the six compounds showed comparable potencies in inhibiting the inactivation of sodium channels, they had greatly variable potencies in inhibiting channel deactivation. Furthermore, unlike pyrethroids, the action of pyrethrins neither depend on nor were enhanced by repeated channel activation. We created a NavMs-based model of the cockroach sodium channel, in which pyrethrin II was docked at the pyrethroid receptor site 1 (PyR1), and proposed a rationale for the observed structure-activity relationship of the six pyrethrins. Our study sheds light on the molecular mechanism of pyrethrum action on sodium channels and reveled differences in the modes of action of the six bioactive constitutes of pyrethrum.

Environmental exposures in early life appear to play an important role in the pathogenesis of childhood asthma, but the potentially modifiable exposures that lead to asthma remain uncertain.We sought to identify early-life environmental risk factors for childhood asthma in a birth cohort of high-risk inner-city children.We examined the relationship of prenatal and early-life environmental factors to the occurrence of asthma at 7 years of age among 442 children.Higher house dust concentrations of cockroach, mouse, and cat allergens in the first 3 years of life were associated with lower risk of asthma (for cockroach allergen: odds ratio per interquartile range increase in concentration, 0.55; 95% CI, 0.36-0.86; P .01). House dust microbiome analysis using 16S ribosomal RNA sequencing identified 202 and 171 bacterial taxa that were significantly (false discovery rate 0.05) more or less abundant, respectively, in the homes of children with asthma. A majority of these bacteria were significantly correlated with 1 of more allergen concentrations. Other factors associated significantly positively with asthma included umbilical cord plasma cotinine concentration (odds ratio per geometric SD increase in concentration, 1.76; 95% CI, 1.00-3.09; P = .048) and maternal stress and depression scores.Among high-risk inner-city children, higher indoor levels of pet or pest allergens in infancy were associated with lower risk of asthma. The abundance of a number of bacterial taxa in house dust was associated with increased or decreased asthma risk. Prenatal tobacco smoke exposure and higher maternal stress and depression scores in early life were associated with increased asthma risk.

For providing their offspring females of the digger wasp species Ampulex compressa hunt cockroaches, paralyze them and attach as a rule one egg to the coxa of one of the mid legs of their prey. We observed the egg-laying behavior and examined with light- and scanning microscopy (i) nearly mature eggs from ovaries of freshly dissected females and (ii) eggs immediately after their deposition on the coxae of their prey. The length of the white bean-shaped eggs varied between 2.2 and 3.0 mm, their diameter between 0.66 and 0.72 mm, and their weight between 345 and 832 μg. The surface of fresh, untreated eggs shows even at higher magnifications (>20.000×) a smooth appearance. However, after conventional fixation, dehydration with ethyl-alcohol and critical-point drying the egg-surface exhibited a little bit texture. The eggs are at two-third of their underside glued to the coxa of the prey. With the naked eye the glue appears as a compact mass. The eggs may be mechanically removed from the substrate (their attachment site); however, in doing so the viscous attachment glue appears in a more fibrous consistence. The polypeptide composition washed off the egg surface and the glue revealed no similarities, whereas the molecular mass of two polypeptides were similar between glue and the Dufour's gland contents.

BACKGROUND: Cockroach allergens are an important cause of IgE-mediated sensitization in inner-city asthmatics. However, cockroach extracts used for diagnosis and immunotherapy are not standardized. OBJECTIVE: To determine the allergen content of non-standardized German cockroach extracts and the levels of sensitization to an expanded set of cockroach allergens as determinants of in vitro extract potency for IgE reactivity. METHODS: Twelve German cockroach extracts were compared for allergen content and for potency of IgE reactivity. Bla g 1, Bla g 2 and Bla g 5 were measured by immunoassays. IgE antibody levels to eight purified recombinant allergens from groups 1, 2, 4, 5, 6, 7, 9 and 11 were measured by ImmunoCAP. IgE antibody binding inhibition assays were performed to assess extract in vitro potencies (IC30) relative to an arbitrarily selected reference extract in five cockroach allergic subjects. RESULTS: Allergen levels were highly variable. Three new major allergens (groups 6, 9 and 11), were identified among highly cockroach-sensitized subjects (CAP-class ≥ 3). Sensitization profiles were unique per subject, without immunodominant allergens. The sum of IgE to eight allergen components showed a good correlation with cockroach-specific IgE (r = 0.88; p < 0.001). In vitro potencies varied among different extracts per subject, and among subjects for each extract. CONCLUSIONS: The in vitro potency of German cockroach extracts for IgE reactivity depends on allergen content and allergen-specific IgE titers of the cockroach-allergic subject. These factors are relevant for selection of potent extracts to be used for immunotherapy and for the design and interpretation of data from immunotherapy trials.

Juvenile hormone (JH) controls insect reproduction and development through an intracellular receptor complex comprising two bHLH-PAS proteins, the JH-binding Methoprene-tolerant (Met) and its partner Taiman (Tai). Many hemimetabolous insects including cockroaches strictly depend on JH for stimulation of vitellogenesis. In termites, the eusocial hemimetabolans, JH also regulates the development of caste polyphenism. Studies addressing the agonist ligand binding to recombinant JH receptors currently include three species belonging to two holometabolous insect orders, but none that would represent any of the hemimetabolous orders. Here, we examined JH receptors in two representatives of Blattodea, the cockroach Blattella germanica and the termite Prorhinotermes simplex. To test the JH-binding capacity of Met proteins from these species, we performed chemical synthesis and tritium labeling of the natural blattodean JH homolog, JH III. Our improved protocol increased the yield and specific activity of [10-3H]JH III relative to formerly available preparations. Met proteins from both species specifically bound [3H]JH III with high affinity, whereas Met variants mutated at a critical position within the ligand-binding domain were incapable of such binding. Furthermore, JH III and the synthetic JH mimic fenoxycarb stimulated dimerization between Met and Tai components of the respective JH receptors of both species. These data present primary evidence for agonist binding by JH receptors in any hemimetabolous species and provide a molecular basis for JH action in cockroaches and termites.

Several cockroach specimens were recovered from the Sinuiju Formation in Paektho-dong, Sinuiju City, North Phyongan Province, Democratic People's Republic of Korea (DPRK). These specimens belong to Habroblattula drepanoides Wang, Liang et Ren, 2007. Fossil plant assemblages also recovered from the Sinuiju Formation are typical of Early Cretaceous floras from warm to temperature regions.

Animals and insects are the main sources of protein. The objective of the present study was to produce a flour from cinereous cockroach (Nauphoeta cinerea) for protein enrichment of wheat bread. To prepare the flour, the dehydrated insects were crushed and sieved to reduce the granulometry to a particle size of 1.18 mm. The flour was analyzed microbiologically and then added in amounts of 5, 10, and 15% (based on wheat flour) in a bread formulation that was analyzed for chemical composition and color, firmness, and specific volume and compared to white wheat bread and whole wheat bread. Sensorial evaluation was carried out on bread enriched with 10% roasted flour as the one that presented the best nutritional characteristics, differing little from the white and whole wheat bread. It is concluded that the use of cinereous cockroach (Nauphoeta cinerea) flour is an efficient way to enrich wheat bread without alterations in sensorial quality.

Numerous cockroach specimens are found in the materials collected in the Sinuiju Formation from Paektho-dong, Sinuiju City, North Phyongan Province, Democratic People's Republic of Korea (DPRK). Of them, there is Perlucipecta aurea Wei et Ren, 2013, which belongs to the Mesoblattinidae. This discovery not only extends the geographic distribution of Perlucipecta in the Mesozoic but also fills a blank in Mesoblattinidae study in Sinuiju region.

Summary Many social species are able to perform collective decisions and reach consensus. However, how the interplay between social interactions, the diversity of preferences among the group members and the group size affects these dynamics is usually overlooked. The collective choice between odourous and odorless shelters is tested for the following three groups of social cockroaches (Periplaneta americana) which are solitary foragers: naive (individuals preferring the odorous shelter), conditioned (individuals without preference), and mixed (combining, unevenly, conditioned, and naive individuals). The robustness of the consensus is not affected by the naive individuals' proportion, but the rate and the frequency of selection of the odorous shelter are correlated to this proportion. In mixed groups, the naive individuals act as influencers. Simulations based on the mechanisms highlighted in our experiments predict that the consensus emerges only for intermediate group sizes. The universality of these mechanisms suggests that such phenomena are widely present in social systems.

A second blattoid species, Cercoula brachyptera gen. et sp. nov. is described from Cretaceous amber. It is placed in Blattoidea because of the combination of bivalvate female subgenital plate and type-A fore-femoral spination. Its relatively small size, and small, slender, pod-like cerci, suggest that the new species is a stem member of Blattoidea. Cercoula brachyptera is the first fossil of brachypterous cockroach. Since wing reduction might be a response of cockroaches to the arid environment, C. brachyptera might indicate an arid microenvironment or a dry season, or even contribute to the possibility of an arid palaeoclimate of the Myanmar amber locality. (C) 2020 Elsevier Ltd. All rights reserved.

Background Exposure to cockroaches is an important asthma trigger, particularly for children with asthma living in inner cities. Integrated pest management is the recommended approach to cockroach abatement; however, it is costly and difficult to implement. The impact of reducing cockroach exposure on asthma outcomes is not known. Objective We sought to test the use of a single intervention, insecticidal bait, to reduce cockroach exposure in the home of children with asthma in New Orleans and to examine the impact of cockroach reduction on asthma outcomes. Methods One hundred two children aged 5 to 17 years with moderate to severe asthma were enrolled in a 12-month randomized controlled trial testing the use of insecticidal bait on cockroach counts and asthma morbidity. Homes were visited 6 times and asthma symptoms were assessed every 2 months. Results After adjustment, intervention homes had significantly fewer cockroaches than did control homes (mean change in cockroaches trapped, 13.14; 95% CI, 6.88-19.39; P P = .03; 1.17, 95% CI, 0.11-2.24, P = .03, respectively) and a higher proportion of children with FEV 1 of less than 80% predicted (odds ratio, 5.74; 95% CI, 1.60-20.57; P = .01) compared with children living in intervention homes. Conclusions Previous research has demonstrated improvement in asthma health outcomes using multifaceted interventions. The strategic placement of insecticidal bait, which is inexpensive, has low toxicity, and is widely available, resulted in sustained cockroach elimination over 12 months and was associated with improved asthma outcomes. This single intervention may be an alternative to multifaceted interventions currently recommended to improve asthma morbidity.

Sense organs that monitor forces in legs can contribute to activation of muscles as synergist groups. Previous studies in cockroaches and stick insects showed that campaniform sensilla, receptors that encode forces via exoskeletal strains, enhance muscle synergies in substrate grip. However synergist activation was mediated by different groups of receptors in cockroaches (trochanteral sensilla) and stick insects (femoral sensilla). The factors underlying the differential effects are unclear as the responses of femoral campaniform sensilla have not previously been characterized. The present study characterized the structure and response properties (via extracellular recording) of the femoral sensilla in both insects. The cockroach trochantero-femoral (TrF) joint is mobile and the joint membrane acts as an elastic antagonist to the reductor muscle. Cockroach femoral campaniform sensilla show weak discharges to forces in the coxo-trochanteral (CTr) joint plane (in which forces are generated by coxal muscles) but instead encode forces directed posteriorly (TrF joint plane). In stick insects, the TrF joint is fused and femoral campaniform sensilla discharge both to forces directed posteriorly and forces in the CTr joint plane. These findings support the idea that receptors that enhance synergies encode forces in the plane of action of leg muscles used in support and propulsion.

Background There is some evidence that dampness, mould and cockroaches can increase the risk of respiratory infections in children but few studies exist from China on this topic. Aim To study associations between domestic early life exposure to biological indoor factors (dampness, mould, cats, dogs, rats, cockroaches), cleaning habits and common cold among pre-school children across China. Methods Children aged 3–6 years (n = 39,782) were recruited from randomly selected day care centres in seven cities in China. Data on common cold and prenatal and postnatal exposure to dampness, mould, windowpane condensation in wintertime (WPC), cats, dogs, cockroaches and rats were assessed by a parentally administered questionnaire. Data on annual ambient temperature and PM 10 was assessed on city level. Associations between high frequency (> 5 colds per year) and long duration (≥ 2 weeks) of common colds in the past year and exposure were calculated by multilevel logistic regression. Results A total of 9.2% had a high frequency and 11.9% had long duration of common cold. Exposure to mould (OR = 1.38, 95% CI 1.24–1.53) and WPC (OR 1.23, 95%CI 1.13–1.33) at birth was associated with frequent common cold. Exposure to dogs at birth was associated with long duration of common cold. (OR = 1.22, 95% CI 1.06–1.41). Exposure to mould (OR = 1.36, 95% CI 1.22–1.54), WPC (OR = 1.27, 95%CI 1.17–1.39) and water leakage (OR 1.34, 95% CI 1.20–1.49) in the current home was associated with frequent common cold. Presence of cockroaches were positively (OR = 1.12, 95% CI 1.02–1.24) and presence of rats (OR = 0.86, 95% CI 0.77–0.96) negatively associated with high frequency of common cold. Daily cleaning was negatively associated with frequent common cold (OR = 0.89, 95% CI 0.81–0.97). Similar associations for mould, WPC, cockroaches and rats were found for long duration. Ambient PM 10 (OR = 1.21, 95% CI 1.21–1.35 per 10 μg/m 3 ) and temperature (OR = 1.13, 95% CI 1.06–1.35 °C) on city level were associated with high frequency of common cold. Associations between cat keeping and high frequency of common cold were found only in southern China. Associations with cockroaches were stronger in northern China. Associations with dampness and mould were the same in the north and south. Conclusions Indoor mould, water damage, windowpane condensation, cockroaches and keeping cats or dogs as pets can be risk factors for common cold while daily cleaning can be protective factor. PM 10 and a warmer climate zone can be other risk factors for common cold.

WOS: 000396955500019, PubMed: 28267493, In previous studies, chitin-based films were produced from chitin nanofibers in dust form and fully characterized. However, chitin films naturally present.in many organisms have not been isolated and characterized. Herein, structurally intact chitin films were successfully extracted from the dorsal pronoturn and the wing of cockroach. Despite using the same extraction procedure, important differences were observed. Especially, hydrophobicity, transparency, antifungal and antibacterial biofilm activities of wing chitin film were recorded notably higher than those of chitin film from the dorsal pronotum. However, better mechanical properties were observed for chitin film from the dorsal pronotum. Notably, among the tested bacteria, two common pathogens could not form biofilms on the surface of the films. This study clearly demonstrated natural chitin films obtained from an insect can provide a new perspective to chitin-based applications where chitin films with high thermal stability, transparency, resistance to bacterial biofilm formation and antifungal activity are needed. (C) 2017 Elsevier Ltd. All rights reserved.

Only seven adult cockroaches have been described from Mesozoic amber. Balatronis cretacea gen. et sp. nov. from the Cenomanian burmite is the most ancient member of the type cockroach family Blattidae and the only one recorded from Cretaceous strata. Individuals represented by immature and adults (n = 14, 4) constitute 3.2 per cents of all Myanmar amber cockroaches surveyed by us – indicating habits close to source trees supported with bark body pattern (absent in sedimentary fossils). Preservation in small-sized pieces suggests longer post-depositional transportation. Its characteristic aposematic coloration suggests direct ancestry to the living repellent harlequin cockroach Neostylopyga rhombifolia, which lost its wings. Along with the bizarre Manipulatoridae, Eadiidae and Alienopteridae species, it exemplifies the high disparity of cockroaches in the ancient amber–producing tropical forest, but also documents the appearance of advanced modern taxa.

Balatronis cretacea Smidova et Lei, 2017 – ancestor of the repellent harlequin cockroach (Insecta: Blattaria) is reported in this issue as the earliest representative of the type cockroach family Blattidae in the Cenomanian Myanmar amber (98 Ma). Balatronis libanensis sp.n. from the Lebanese amber (130 Ma) extends the palaeogeographic (to Gondwana) and chronostratigraphic (to Early Cretaceous) range of this advanced Mesozoic bark cockroach and shifts the expected origin of the Blattidae to the J/K boundary. In relation also to the living harlequin Neostylopyga rhombidifolia , B. libanensis is primitive in being extremely small, less coloured and with well-developed wings. It has the standard cockroach head and rudimentary, but clearly visible plesiomorphic macula-like central ocellus (as the only representative of the modern Mesoblattinidae–Blattidae–Ectobiidae–Blaberidae lineage) and represents the earliest significant record of an aposematic and thus very probably also a repellent and/or poisonous insect.

Periplaneta americana, Blatta orientalis, Blattella germanica and Supella longipalpa are the most common worldwide cockroaches that mentioned in the "22 common pest" or "22 dirty" species named as "group I". They are able to infest any type of buildings. A meta-analysis review was conducted between January 2015 and July 2016 on any literature published about infestation of cockroaches. Scientific reports and papers about infestation of cockroaches and relevant topics were collected from various specific scientific websites such as PubMed, Web of Science, ScienceDirect, Springer, Elsevier, Scopus, and Google Scholar. About 271 scientific reports and papers were collected and after a preliminary review, 63 were selected to become part of the detailed synthesis review and meta-analysis. Results showed that the global world mean infestation trend of cockroaches, and B. germanica and P. americana cockroach species ranged 49.0-55.0, 40.0-70.0 and 60.0-70.0%, respectively suggests that their infestation trend are increasing. The global world mean infestation of cockroaches, and B. germanica and P. americana cockroach species were 52.3, 55.2 and 65.4, respectively. There was a significant difference between the global world mean infestation of cockroaches and P. americana cockroach species (P=0.019). The global mean infestation trend of cockroaches in the human dwelling environments and world ranged 55.0-65.0 and 50.0-70.0%, respectively suggests that their infestation trend are increasing. The global world mean infestation of cockroaches in the human dwelling environments and world were 60.4 and 57.7%, respectively. Although some factors affect the infestation of cockroaches and the sanitation and quality structure of the buildings are also being improved. While as present study reveal that the globally the world infestation trend of cockroaches are being increased and recent studies also indicate that the prevalence of asthma has increased dramatically over the decades suggest that infestation of cockroaches can directly affect the development of asthma.

Heteropoda venatoria is a venomous spider species distributed worldwide and has a characteristic habit of feeding on insects. Reverse-phase high-performance liquid chromatography and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry analyses revealed that H. venatoria venom contains hundreds of peptides with a predominant molecular weights of 3000-5000 Da. Intra-abdominal injection of the venom had severe toxic effects on cockroaches and caused death at higher concentrations. The LD50 was 28.18 μg/g of body weight in the cockroach. It was found that the venom had potent inhibitory effect on voltage-gated sodium channels (VGSCs) in Periplaneta americana cockroach dorsal unpaired median (DUM) neurons with an IC50 values of 6.25 ± 0.02 μg/mL. However, 100 μg/mL venom only partially blocked VGSC currents in rat dorsal root ganglion cells, a much lower inhibitory effect than that on DUM VGSCs. Our results indicate that the venom of H. venatoria contains diverse neurotoxins that might become new leads for bioinsecticides.

Circadian clocks control physiology and behavior of organisms in synchrony with external light dark cycles in changing photoperiods. The Madeira cockroach Rhyparobia maderae was the first model organism in which an endogenous circadian clock in the brain was identified. About 240 neurons constitute the cockroach circadian pacemaker network in the accessory medulla. The expression of high concentrations of neuropeptides, among them the most prominent circadian coupling factor pigment-dispersing factor, as well as their ability to generate endogenous ultradian and circadian rhythms in electrical activity and clock gene expression distinguish these pacemaker neurons. We assume that entrainment to light-dark cycles and the control of 24h rest-activity rhythms is achieved via peptidergic circuits forming autoreceptive labeled lines.

Summary Animals can follow olfactory traces to find food, detect a sexual mate, or avoid predators. A new study reveals that pheromone-specific projection neurons in the cockroach have a spatially tuned receptive field, and allow encoding spatial information of an odorant.

Extensive use of insecticides has caused widespread resistance in German cockroach (Blattella germanica) populations on a global scale. Biological control has potential to mitigate insecticide resistance, and Metarhizium anisopliae, an entomopathogenic fungus, has shown good efficacy against cockroaches alone and in combination with various insecticides, including boric acid. To investigate the mechanism(s) that underlie synergism between M. anisopliae and boric acid, we conducted dose-response assays with combinations of fungus and boric acid fed to cockroaches and histological observations of the midgut and we characterized the gut microbiome of treated cockroaches. The combination treatments were synergistic with co-toxicity factors >20 at 4 out of 12 treatments and LT50 values of 5 days at the highest concentration of boric acid. M. anisopliae reached the hemocoel faster when it was ingested with boric acid, likely because boric acid disrupted the epithelial cells of the midgut. The gut microbiome was also altered by these treatments. The abundance of Parabacteroides and Enterococcus, with known anti-inflammatory and antifungal activity, declined in boric acid and combination treatments, whereas Weissella, an opportunistic pathogen, significantly increased in these treatments. We conclude that two major mechanisms underlie this synergism: (1) boric acid facilitates the penetration of M. anisopliae by physically and chemically disrupting the midgut, and (2) by altering the gut microbiome, boric acid promotes survival and virulence of M. anisopliae in the harsh gut environment.

The family Liberiblattinidae is a small but phylogenetically most important group of Blattaria (cockroaches), comprising 17 Mesozoic genera and 20 species. The genus Stavba Vrsanska et Vrsanský in Vrsanský et al. (2019c) of this family consists of two known species. Stavba jarzembowskii sp. nov. is described and figured based on an exceptionally preserved male individual in mid-Cretaceous amber from Myanmar. It is distinguished from the other two species by having more round eyes, a narrower body, broader wings with broader costal area and less crossveins in the radial sector and medial field, and relatively uncurved A veins. Our new find further adds the diversity within this genus and of the cockroaches in 99 Ma tropical forests of Burmese amber.

The entomotoxic potential of Manilkara rufula crude extract (CEMR) and its aqueous (AFMR) and methanolic (MFMR) fractions were evaluated against Nauphoeta cinerea cockroaches. The results point out to a direct modulation of octopaminergic and cholinergic pathways in insect nervous system. CEMR induced an anti-acetylcholinesterase (AChE) effect in cockroach brain homogenates. CEMR significantly decreased the cockroach heart rate in semi-isolated heart preparations. CEMR also caused a broad disturbance in the insect behavior by reducing the exploratory activity. The decreased antennae and leg grooming activities, by different doses of CEMR, mimicked those of phentolamine activity, a selective octopaminergic receptor antagonist. The lethargy induced by CEMR was accompanied by neuromuscular failure and by a decrease of sensilla spontaneous neural compound action potentials (SNCAP) firing in in vivo and ex vivo cockroach muscle-nerve preparations, respectively. AFMR was more effective in promoting neuromuscular paralysis than its methanolic counterpart, in the same dose. These data validate the entomotoxic activity of M. rufula. The phentolamine-like modulation induced in cockroaches is the result of a potential direct inhibition of octopaminergic receptors, combined to an anti-AChE activity. In addition, the modulation of CEMR on octopaminergic and cholinergic pathways is probably the result of a synergism between AFMR and MFMR chemical compounds. Further phytochemical investigation followed by a bio-guiding protocol will improve the molecular aspects of M. rufula pharmacology and toxicology to insects.

Three complete mitochondrial genomes of Blaberidae (Insecta: Blattodea) (Gromphadorhina portentosa, Panchlora nivea, Blaptica dubia) and one complete mt genome of Blattidae (Insecta: Blattodea) (Shelfordella lateralis) were sequenced to further understand the characteristics of cockroach mitogenomes and reconstruct the phylogenetic relationship of Blattodea. The gene order and orientation of these four cockroach genomes were similar to known cockroach mt genomes, and contained 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and one control region. The mt genomes of Blattodea exhibited a characteristics of a high A+T composition (70.7%-74.3%) and dominant usage of the TAA stop codon. The AT content of the whole mt genome, PCGs and total tRNAs in G. portentosa was the lowest in known cockroaches. The presence of a 71-bp intergenic spacer region between trnQ and trnM was a unique feature in B. dubia, but absent in other cockroaches, which can be explained by the duplication/random loss model. Based on the nucleotide and amino acid datasets of the 13 PCGs genes, neighbor-joining (NJ), maximum parsimony (MP), maximum likelihood (ML) and bayesian inference (BI) analyses were used to rebuild the phylogenetic relationship of cockroaches. All phylogenetic analyses consistently placed Isoptera as the sister cluster to Cryptocercidae of Blattodea. Ectobiidae and Blaberidae (Blaberoidea) formed a sister clade to Blattidae. Corydiidae is a sister clade of all the remaining cockroach species with a high value in NJ and MP analyses of nucleotide and amino acid datasets, and ML and BI analyses of the amino acid dataset.

The present study aimed to increase our understanding about the mode of toxic action of organophosphate pesticides in insects by evaluating the biochemical and neurobehavioral characteristics in Nauphoeta cinerea exposed to chlorpyrifos (CPF)-contaminated diet. The insects were exposed for 35 consecutive days to CPF at 0.078, 0.15625, 0.3125 and 0.625μg/g feed. Locomotor behavior was assessed for a 10-min trial in a novel arena and subsequently, biochemical analyses were carried out using the cockroaches' heads. In comparison to control, CPF-exposed cockroaches showed significant decreases in the total distance traveled, body rotation, turn angle and meandering, along with significant increase in the number of falls, time and episodes of immobility. The marked decrease in the exploratory profiles of CPF-exposed cockroaches was confirmed by track plots, whereas occupancy plot analyses showed a progressive dispersion at 0.15625μg/g feed group. Moreover, the heads of CPF-exposed cockroaches showed marked decrease in acetylcholinesterase activity and antioxidant status with concomitant significant elevation in dichlorofluorescein oxidation and lipid peroxidation levels in CPF-treated cockroaches. Gas Chromatography-Mass Spectrometry analyses revealed bioaccumulation of CPF in cockroaches exposed to concentrations above 0.078μg/g feed. The findings from this investigation showed N. cinerea as a value model organism for the risk assessment of environmental organophosphate contamination in insects.

The scorpion Tityus serrulatus venom comprises a complex mixture of molecules that paralyzes and kills preys, especially insects. However, venom components also interact with molecules in humans, causing clinic envenomation. This cross-interaction may result from homologous molecular targets in mammalians and insects, such as (NEP)-like enzymes. In face of these similarities, we searched for peptides in Tityus serrulatus venom using human NEP as a screening tool. We found a NEP-inhibiting peptide with the primary sequence YLPT, which is very similar to that of the insect neuropeptide proctolin (RYLPT). Thus, we named the new peptide [des-Arg(1)]-proctolin. Comparative NEP activity assays using natural substrates demonstrated that [des-Arg(1)]-proctolin has high specificity for NEP and better inhibitory activity than proctolin. To test the initial hypothesis that molecular homologies allow Tityus serrulatus venom to act on both mammal and insect targets, we investigated the presence of a NEP-like in cockroaches, the main scorpion prey, that could be likewise inhibited by [des-Arg(1)]-proctolin. Indeed, we detected a possible NEP-like in a homogenate of cockroach heads whose activity was blocked by thiorphan and also by [des-Arg(1)]-proctolin. Western blot analysis using a human NEP monoclonal antibody suggested a NEP-like enzyme in the homogenate of cockroach heads. Our study describes for the first time a proctolin-like peptide, named [des-Arg(1)]-proctolin, isolated from Tityus serrulatus venom. The tetrapeptide inhibits human NEP activity and a NEP-like activity in a cockroach head homogenate, thus it may play a role in human envenomation as well as in the paralysis and death of scorpion preys.

Luteolin (3', 4', 5, 7-tetrahydroxyflavone) is a polyphenolic compound found in foods of plant origin and has been reported to possess antioxidant and neuroprotective properties. However, there is dearth of information on the beneficial effects of luteolin on methylmercury (MeHg), a long-established neurotoxic compound in animals and humans. This study evaluated the effect of luteolin on MeHg-induced behavioral and biochemical deficits, using lobster cockroach Nauphoeta cinerea as an alternative and complementary animal model. The insects were exposed for 35 consecutive days to either MeHg alone (0.05 mg/g feed) or in combination with luteolin at 0.25, 0.5 and 1.0 mg/g feed. Locomotor behavior was assessed using video-tracking software during a 10-min trial in a novel arena and subsequently, biochemical analyses were carried out using the cockroaches' heads. Luteolin supplementation dose-dependently reversed the MeHg-induced locomotor deficits and enhanced the exploratory profiles of MeHg-exposed cockroaches as confirmed by track and occupancy plot analyses. Luteolin reversed the MeHg-induced acetylcholinesterase activity inhibition, decreased dichlorofluorescein oxidation and lipid peroxidation levels, but increased total thiol level and catalase and glutathione S-transferase activities in the treated cockroaches. In conclusion, luteolin prevented oxidative stress indices and neurobehavioral deficits in a Nauphoeta cinerea model of MeHg toxicity.

The present paper reports the effects of Metarhizium anisopliae, Isaria fumosoroseus and Hirsutella thompsonaii on Periplaneta americana. I. fumosoroseus and H. thompsonaii were cultured at 28±1°C on potato carrot agar and M. anisopliae was cultured at 28±1°C on potato dextrose agar for 14days. Conidial suspensions of fungi were given to cockroaches through different routes. M. anisopliae shows high virulence against adult cockroaches and mortality ranges from 38.65% to 78.36% after 48h. I. fumosoroseus and H. thompsonii show less virulence compared to M. anisopliae. We also investigated the effect of these three fungi on the activity of lactate dehydrogenase, lipid peroxidation and catalase in different tissues of the insect to gain an understanding of the different target site. The result suggested that the activity of lactate dehydrogenase, catalase and level of malondialdehyde varies in different organs and through different routes of exposure. Based on mortality percentages, all tested fungi had high potentials for biocontrol agents against P. americana. Our study reveals for the first time that I. fumosoroseus and H. thompsonaii fungal infections initiate oxidative stress in the midgut, fat body, whole body and hemolymph of cockroach thereby suggesting them to be the target organs for oxidative damage.

Two 2 captive giant burrowing cockroaches ( Macropanesthia rhinoceros ) with unusual conformation developed progressive obesity followed by faecal impaction in the absence of changes in husbandry. Fluid therapy and removal of the faecal impaction under general anaesthesia was successful in the treatment of 1 case. Radiography was a useful diagnostic tool for evaluating M. rhinoceros whereas ultrasonography was unrewarding. The potential for obesity associated with the "thrifty" phenotype in pet cockroaches has implications for the commercial rearing of cockroaches for sale and for veterinarians approaching obesity and its complications in this and similar species.

Individuals are different, but they can work together to perform adaptive collective behaviours. Despite emerging evidence that individual variation strongly affects group performance, it is less clear to what extent individual variation is modulated by participation in collective behaviour. We examined light avoidance (negative phototaxis) in the gregarious cockroach Blaberus discoidalis, in both solitary and group contexts. Cockroaches in groups exhibit idiosyncratic light-avoidance performance that persists across days, with some individual cockroaches avoiding a light stimulus 75% of the time, and others avoiding the light just above chance (i.e. ~50% of the time). These individual differences are robust to group composition. Surprisingly, these differences do not persist when individuals are tested in isolation, but return when testing is once again done with groups. During the solo testing phase cockroaches exhibited individually consistent light-avoidance tendencies, but these differences were uncorrelated with performance in any group context. Therefore, we have observed not only that individual variation affects group-level performance, but also that whether or not a task is performed collectively can have a significant, predictable effect on how an individual behaves. That individual behavioural variation is modulated by whether a task is performed collectively has major implications for understanding variation in behaviours that are facultatively social, and it is essential that ethologists consider social context when evaluating individual behavioural differences.

Evolution has perfected very different six-legged walking machines from common neural and biomechanical components in an ancestral insect, as exemplified by the American cockroach and the stick insect. Comparative experimental investigations of both intact animals and reduced neural preparations, integrated with mathematical modeling, have been instrumental in advancing our understanding of insect locomotion. Locomotion in stick insects and cockroaches can be described by a related series of mathematical models that describe and quantify the effects of central coupling and feedback, and help explore the role of descending inputs (from higher neuronal centers) and neuromodulation. Insights into sensory–motor interactions and adaptive motor control in insects are useful in designing more responsive, robust, and adaptable bio-robots, which, in turn, can contribute to hypothesis-testing in biology.