BACKGROUND Insect eggshells must combine protection for the yolk and embryo with provisions for respiration and for the entry of sperm, which are ensured by aeropyles and micropyles, respectively. Insects which oviposit the eggs in an egg-case have a double problem of respiration as gas exchange then involves two barriers. An example of this situation is found in the cockroach Blattella germani...

The ribosomal DNA (rDNA) cluster of insects contains several hundred repeating structural-functional units and, therefore, is a typical example of a multigene family. Eukaryotic ribosomal RNA (rRNA) genes (18S, 5.8S, and 28S like) are arranged in tandemly repeated clusters in the nucleolus organizers, separated by several spacers, namely the nontranscribed spacer, the external transcribed space...

background: leishmaniasis is a vector-borne disease caused by flagellated protozoan parasites of the genus leishmania, which affects both humans and other mammals. most of the available drugs against the disease are toxic and some are parasite resistance to them. objective: the purpose of this study was to examine the effect of mespilus germanica extract on cutaneous leishmaniasis (cl) in balb/...

Vespula germanica is a social wasp that has become established outside its native range in many regions of the world, becoming a major pest in the invaded areas. In the present work we analyze social communication processes used by V. germanica when exploiting un-depleted food sources. For this purpose, we investigated the arrival pattern of wasps at a protein bait and evaluated whether a forag...

Na(+), K(+)-ATPases is a heterodimer protein consisting of α- and β-subunits that control the ion transport through cell membranes. In insects the β-subunit of the Na(+), K(+)-ATPase, known as Nervana, was characterized as a nervous system-specific glycoprotein antigen from adult Drosophila melanogaster heads. Nervana is expressed ubiquitously in all insect tissues, and in epithelial cells appe...

Although a number of species live syanthropically with humans, few rely entirely on humans for their survival and distribution. Unlike other cosmopolitan human commensals, the German cockroach (Blattella germanica), an insect of both public and livestock health concern, is considered incapable of dispersal outside human dwellings. Patterns of genetic association are therefore constrained and ma...

Several insecticide bait formulations were evaluated for their attractiveness to cockroaches in olfactometer assays in the laboratory and in trapping experiments in the field. Included in the assays were bait stations, gels, pastes, and a powder that contained one of the following active ingredients: abamectin, boric acid, chlorpyrifos, or hydramethylnon. There were significant differences amon...

Cockroach allergy is a health problem in many parts of the world. In urban environments, indoor exposure to cockroach allergens involves a risk of asthma. The aim of this study was to measure the mass fraction of Bla g 1, a major allergen of the German cockroach (Blatella germanica) in 30 house samples, collected at random from Zagreb area households, Croatia. Dust samples were collected on cel...

Abstract Patterns of juvenile hormone have been intensively studied in the cockroach Blattella germanica under different physiological situations. However, data have been mainly obtained in vitro, and refer to hormone synthesized by isolated corpora allata, whereas information available on hormone concentration in the hemolymph is restricted to adult females. In order to complement our studies ...

Juvenile Hormone (JH) represses metamorphosis of young instars in insects. One of the main players in hormonal signalling is Methoprene-tolerant (Met), which plays the role of JH receptor. Using the Polyneopteran insect Blattella germanica as the model and RNAi for transcript depletion, we have confirmed that Met transduces the antimetamorphic signal of JH in young nymphs and plays a role in th...