Naturwissenschaften
December 2010
The olfactory circuitry of Drosophila melanogaster is becoming increasingly clear. However, how olfactory processing translates into appropriate behavioral responses is still poorly understood. Using a sibling species approach, we tested how a perturbation in the olfactory circuitry affects odor preference.
View Article and Find Full Text PDFBackground: The European corn borer (ECB), Ostrinia nubilalis, is a textbook example of pheromone polymorphism. Males of the two strains (Z and E) prefer opposite ratios of the two pheromone components, Z11- and E11-tetradecenyl acetate, with a sex-linked factor underlying this difference in preference. The male antennal lobes of the two strains contain a pheromone sensitive macroglomerular complex (MGC) that is identical in morphology, but reversed in functional topology.
View Article and Find Full Text PDFBackground: The European Corn Borer, Ostrinia nubilalis (Hubner), is a keystone model for studies on the evolution of sex pheromone diversity and its role in establishing reproductive isolation. This species consists of two sympatric races, each utilizing opposite isomers of the same compound as their major pheromone component. Female production and male response are congruent in each race, and males from each strain exhibit phenotypic differences in peripheral physiology.
View Article and Find Full Text PDFThe nasal botfly Oestrus ovis (Diptera, Cyclorrhapha: Oestridae) is a myiasis-causing insect species, which affects the health of sheep, goats and humans. Gravid females are viviparous and larviposit into the animal's nostrils. Host-searching and larvipositing flies are visually guided and influenced by climatic conditions, whereas olfaction seemed to play no role in this process.
View Article and Find Full Text PDFBackground: the role of chemotherapy in advanced malignant peripheral nerve sheath tumor (MPNST) is unclear.
Patients And Methods: chemotherapy-naive soft tissue sarcomas (STS) patients treated on 12 pooled nonrandomized and randomized European Organization for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group trials were retrospectively analyzed. Clinical outcomes, overall survival, progression-free survival (PFS) and response were determined for MPNST and other STS histotypes and compared.
The European corn borer Ostrinia nubilalis (Hübner) is a model of evolution of sexual communication in insects. Two pheromone strains produce and respond to opposite ratios of the two pheromone components, Z11 and E11-tetradecenylacetate. The Z-strain uses a ratio of 97:3 of Z11:E11 tetradecenylacetate, whereas the E-strain uses a ratio of 1:99.
View Article and Find Full Text PDFWith the rapid advance of bio-genetic technology, it will soon be possible for parents to design children who are born with certain genetic traits. This raises the question whether parents should be allowed to use this technology to engineer their children as they please. In this context it is often thought and argued that liberalism, which has a reputation for being permissive of all kinds of practices, grants parents the right to do so.
View Article and Find Full Text PDFOlfaction in the fruit fly Drosophila melanogaster is increasingly understood, from ligand-receptor-neuron combinations to their axonal projection patterns into the antennal lobe . Drosophila thus offers an excellent opportunity to study the evolutionary and ecological dynamics of olfactory systems. We compared the structure and function of the generalist D.
View Article and Find Full Text PDFMosquito behavior is heavily dependent on olfactory and mechanosensory cues, which are detected by receptor neurons on the antenna and on the palps. Recent progress in mosquito sensory genomics highlights the need for an up-to-date understanding of the neural architecture of the mosquito brain. Here we present a detailed description of the neural structure of the primary target of the majority of these neurons, the deutocerebrum, in the African malaria (Anopheles gambiae) and yellow fever (Aedes aegypti) mosquitoes.
View Article and Find Full Text PDFThis study reports on the development and application of a whole sediment toxicity test using a benthic cladoceran Chydorus sphaericus, as an alternative for the use of pelagic daphnids. A C. sphaericus laboratory culture was started and its performance under control conditions was optimised.
View Article and Find Full Text PDFAim: Matrix metalloproteinases (MMPs) play an eminent role in airway injury and remodelling. We explored the hypothesis that pulmonary MMP levels would differ early after birth (2-4 days) between infants with resolving respiratory distress syndrome (RDS) and infants developing chronic lung disease of prematurity (CLD).
Methods: Thirty-two prematurely born infants (gestational age < or =30 weeks) diagnosed with RDS were included.
Female mosquitoes are noted for their ability to use odours to locate a host for a blood meal. Two sensory organs contribute to their sense of smell: the maxillary palps, which measure the level of CO2, and the antennae, which detect other host-released odours. To establish the relative importance and interactions of CO2 and other body emissions in freely flying mosquitoes, we presented female yellow fever mosquitoes Aedes aegypti L.
View Article and Find Full Text PDFKawasaki disease (KD) is an acute febrile syndrome of childhood, characterized by vasculitis of the medium-sized arteries. White blood cell counts and the inflammatory parameter C-reactive protein (CRP) are known to be elevated in the acute phase of the disease. In this study we investigated the course of inflammatory cell type-specific parameters in KD over a longer period of time.
View Article and Find Full Text PDFMebendazole is a common benzimidazole anthelmintic that is water insoluble. It is reported to exist in three different polymorphic forms in the solid state, i.e.
View Article and Find Full Text PDFA series of thioacridone compounds that were previously shown to have DNA binding interaction, were screened for antimalarial activity. The new compounds were assessed for in vitro antimalarial activity against a chloroquine sensitive (D10) strain of the malaria parasite Plasmodium falciparum, using a lactate dehydrogenase (PfLDH) assay. In the series, the IC(50) values ranged from 0.
View Article and Find Full Text PDFThe well-reported, but moderate antitumor activity of the acronycine alkaloid led us to synthesize a novel series of thioacridone compounds related to acronycine, as potential anticancer agents. Compounds were designed either as DNA intercalating agents, or as DNA intercalating agents with covalent bond forming potential. Bathochromic shifts of the compounds upon complexation with salmon testis DNA suggested intercalation as the mode of DNA binding.
View Article and Find Full Text PDFSerum levels of cytokines (IL-4, IL-5, IFN-gamma, TNF-alpha), cytokine receptors (TNFR I and II) and one monokine (neopterin) were estimated in seven leprosy patients to establish disease associated markers for reversal reactions (RR). Sera were collected at diagnosis of leprosy, at the onset of reversal reaction and at different time points during and at the end of prednisone treatment of reactions. It was expected that the serum cytokine and monokine profile before and at different time points during reactions would provide guidelines for the diagnosis and monitoring of reversal reactions in leprosy.
View Article and Find Full Text PDFProc Biol Sci
November 2003
The Drosophila melanogaster subgroup has been the focus of numerous studies about evolution. We address the question of how the olfactory code has evolved among the nine sister species. By using in vivo electrophysiological measurements, so called single-cell recordings, we have established the ligand affinity of a defined subset of olfactory receptor neurons (ORNs) across all nine species.
View Article and Find Full Text PDFBackground: Lower respiratory tract infection caused by respiratory syncytial virus (RSV) is in part an immune-mediated disease. For that reason corticosteroids might be effective, especially in patients with severe RSV lower respiratory tract infection. Our aim was to assess the effect of dexamethasone on tracheal viral load and airway inflammation in patients with RSV infection.
View Article and Find Full Text PDFUsing a dual-choice olfactometer, the role of L-lactic acid was investigated in relation to host-seeking and selection by female Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) mosquitoes in a Y-tube bioassay. L-lactic acid alone was not attractive, but it significantly augmented the attractiveness of CO2, skin odour and skin-rubbing extracts from humans and other vertebrates. Comparing the left and right index fingers of the same person, one could be made more attractive than the other by adding L-lactic acid to the air stream over that finger.
View Article and Find Full Text PDFIn field studies, Anopheles gambiae Giles sensu stricto obtains most blood meals from humans, whereas Anopheles quadriannulatus Theobald bites predominantly bovids. We investigated whether host odors modulate the host preference of these mosquito species. In a dual-choice olfactometer, mosquitoes were given a choice between clean air and putative host-specific odor blends.
View Article and Find Full Text PDFThe effect of sediment-bound cadmium on several life history parameters of the benthic cladoceran Chydorus piger, was tested in the laboratory. It was investigated whether a test with C. piger is an ecologically realistic alternative for the Daphnia test applied to sediments.
View Article and Find Full Text PDFRisk assessment procedures use toxicity tests in which organisms are subjected to chemicals under otherwise constant and favorable experimental conditions. Because variable and suboptimal environmental conditions are common aspects of natural ecosystems, the hazard of underestimation of risk arises. Therefore, an uncertainty factor is used in the extrapolation of results of standard toxicity tests to field situations.
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