bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective information use in parasitoid wasps
Authors: Thiel Andra , Hoffmeister Thomas 
Published: May 2006

Abstract
Foraging animals frequently have to decide where to search, what host or prey to accept, and when to leave a patch. To achieve optimal patch exploitation rates, foragers can base their decisions on information about the quality of the current patch and on an estimate of the quality of the entire habitat. The latter has rarely been studied to date. We have analysed the patch-leaving behaviour of the parasitic wasp Asobara tabida Nees (Hymenoptera: Braconidae), a solitary parasitoid of Drosophila larvae, as a function of previous experience. Females were confronted with patches containing different numbers of larvae, which were either unparasitised, or parasitised by a conspecific or larvae of different host species. Our results show that females of A. tabida were able to recognise the different qualities of the patches that we offered but that they used information about host density, host species or parasitism status of the host to different degrees during subsequent patch visits. Encounters with an unsuitable host species had a great impact on future patch-leaving decisions while the effect of host density was relatively weak. If wasps had encountered previously parasitised hosts no response could be detected during subsequent visits. We argue that the various information sources provided are of different value for the searching female and that this might explain the observed pattern of selective information use.
Olfactory learning by predatory arthropods
Authors: de Boer Jetske , Dicke Marcel 
Published: May 2006

AbstractMany natural enemies of herbivorous arthropods can use herbivore-induced plant volatiles to locate their prey. The composition of herbivore-induced volatile blends is highly variable, e.g., for different plant or herbivore species. When this variation is predictable during the lifetime of an individual, learning is expected to be adaptive for natural enemies that use such information. Learning has indeed been demonstrated many times for parasitoid wasps that use herbivore-induced plant volatiles to locate their hosts. However, evidence for learning of plant volatiles by predatory mites and insects is scarce and this is the topic of the present paper. We first review previously published research that demonstrated that anthocorid bugs and the predatory mite Phytoseiulus persimilis have the capacity to learn. Next, we present new evidence for an effect of previous experiences of P. persimilis on its responses to mixtures of volatile blends, induced by prey or non-prey herbivores. Finally, we discuss the ecological relevance of olfactory learning by predatory arthropods and the need to address this topic in future research.
Gustatory response and appetitive learning in Microplitis croceipes in relation to sugar type and concentration
Authors: Wäckers Felix , Bonifay Claire , Vet Louise , Lewis Joe 
Published: May 2006

Abstract
Insects can be conditioned to respond to odours through associative learning. Various learning parameters, such as the rate of odour acquisition, are known to depend on the type of conditioned stimulus. Here we investigate to what extent appetitive conditioning in the parasitoid Microplitis croceipes is also affected by characteristics of the food reward (unconditioned stimulus). We tested 1 M solutions of eight sugars naturally occurring in nectar and honeydew with respect to their effect on parasitoid gustatory response and their suitability as an unconditioned stimulus in the process of associative odour learning. To test for concentration effects, a separate experiment compared parasitoid performance with 1 M and 0.25 M of sucrose, respectively. Only exposure to glucose, fructose, sucrose and melezitose enhanced feeding relative to control individuals provided water. Raffinose, mannose, galactose and melibiose did not increase or decrease consumption, indicating that these sugars are neither phagostimulants nor phagodeterrents. In the conditioning experiments, parasitoids were allowed to feed on a particular sugar solution while being exposed to the floral odour cineole. Parasitoids that had been trained with the stimulatory sugars subsequently showed a clear conditioned feeding response to the cineole. Conditioning with galactose, mannose and melibiose, on the other hand, did not lead to successful odour acquisition. Conditioning with raffinose increased the tendency of the parasitoid to exhibit a conditioned feeding response, even though this response was significantly shorter than the response following training with stimulatory sugars.The level of cineole response was not significantly influenced by the concentration of a sucrose solution, even though the 0.25 M concentration was a weaker feeding stimulant.Our findings indicate that gustatory perception is the principal unconditioned stimulus in appetitive learning. The results with raffinose indicate that postingestive feedback may be involved in food associative learning as well.
Learning in the context of sexual behaviour in insects
Authors: Dukas Reuven 
Published: May 2006

AbstractThere has been little ecological and evolutionary research on learning in the context of sexual behaviour in insects. The traditional views still dominating the literature are that insects are short-lived and have little opportunity to learn about courtship and mating. In this paper I challenge these views by illustrating, theoretically, that at least some insects have ample opportunities to learn in the context of sexual behaviour and that such learning may be beneficial. Some of the best empirical evidence for learning about sexual behaviour in insects is reviewed and future directions in this fruitful area of research are suggested. The role of learning in insect sexual behaviour has probably been underestimated. Such learning may have had an important effect on sexual selection and incipient speciation.
The efficacy of selective serotonin reuptake inhibitors in adult social anxiety disorder: a meta-analysis of double-blind, placebo-controlled trials
Authors: Hedges Dawson W. , Brown Bruce L. , Shwalb David A. , Godfrey Kirk , Larcher A. Manja 
Published: May 2006

Social anxiety disorder is associated with impairment in social and occupational functioning, significant personal distress and a possible economic burden, resulting in a reduction in quality of life. To understand better the efficacy of selective serotonin reuptake inhibitors in social anxiety disorder, randomized, double-blind, placebo-controlled trials were evaluated. Pubmed and PsychINFO electronic databases were searched for social anxiety disorder, social phobia, selective serotonin reuptake inhibitors, citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine and sertraline. Fifteen published, randomized, double-blind, placebo-controlled trials of selective serotonin reuptake inhibitors in social anxiety disorder were identified. Design, subject number, drug and dose, trial length, rating instruments, and baseline and end point data were extracted and then verified independently by a second investigator. Effect sizes were calculated from mean changes in drug and placebo groups in the Liebowitz Social Anxiety Scale and the Sheehan Disability Scale, as well as from other scales where available. For the binary data of the Clinical Global Impression of Change scores, Θlog-odds ratios (the effect-size measure appropriate for binary data) were calculated from proportion changes. Effect sizes for the Liebowitz Social Anxiety Scale ranged from -0.029 to 1.214. Effect sizes for the Sheehan Disability Scale ranged from 0.203 to 0.480 for work, 0.237 to 0.786 for social function, and 0.118 to 0.445 for family function. ΘThe log-odds ratios for Clinical Global Impression of Change scores ranged from 0.644 to 3.267. Consistent with previous studies, selective serotonin reuptake inhibitors appear more effective than placebo for social anxiety disorder, with improvement extending into social and occupational function.
Long-term clearance from small airways in subjects with ciliary dysfunction
Authors: Lindström Maria , Falk Rolf , Hjelte Lena , Philipson Klas , Svartengren Magnus 
Published: May 2006

AbstractThe objective of this study was to investigate if long-term clearance from small airways is dependent on normal ciliary function.Six young adults with primary ciliary dyskinesia (PCD) inhaled111Indium labelled Teflon particles of 4.2 μm geometric and 6.2 μm aerodynamic diameter with an extremely slow inhalation flow, 0.05 L/s. The inhalation method deposits particles mainly in the small conducting airways. Lung retention was measured immediately after inhalation and at four occasions up to 21 days after inhalation. Results were compared with data from ten healthy controls. For additional comparison three of the PCD subjects also inhaled the test particles with normal inhalation flow, 0.5 L/s, providing a more central deposition. The lung retention at 24 h in % of lung deposition (Ret24) was higher (p < 0.001) in the PCD subjects, 79 % (95% Confidence Interval, 67.6;90.6), compared to 49 % (42.3;55.5) in the healthy controls. There was a significant clearance after 24 h both in the PCD subjects and in the healthy controls with equivalent clearance. The mean Ret24with slow inhalation flow was 73.9 ± 1.9 % compared to 68.9 ± 7.5 % with normal inhalation flow in the three PCD subjects exposed twice. During day 7–21 the three PCD subjects exposed twice cleared 9 % with normal flow, probably representing predominantly alveolar clearance, compared to 19 % with slow inhalation flow, probably representing mainly small airway clearance.This study shows that despite ciliary dysfunction, clearance continues in the small airways beyond 24 h. There are apparently additional clearance mechanisms present in the small airways.
Predicting DNA-binding sites of proteins from amino acid sequence
Authors: Yan Changhui , Terribilini Michael , Wu Feihong , Jernigan Robert L , Dobbs Drena , Honavar Vasant 
Published: May 2006

Abstract

Background
Understanding the molecular details of protein-DNA interactions is critical for deciphering the mechanisms of gene regulation. We present a machine learning approach for the identification of amino acid residues involved in protein-DNA interactions.

Results
We start with a Naïve Bayes classifier trained to predict whether a given amino acid residue is a DNA-binding residue based on its identity and the identities of its sequence neighbors. The input to the classifier consists of the identities of the target residue and 4 sequence neighbors on each side of the target residue. The classifier is trained and evaluated (using leave-one-out cross-validation) on a non-redundant set of 171 proteins. Our results indicate the feasibility of identifying interface residues based on local sequence information. The classifier achieves 71% overall accuracy with a correlation coefficient of 0.24, 35% specificity and 53% sensitivity in identifying interface residues as evaluated by leave-one-out cross-validation. We show that the performance of the classifier is improved by using sequence entropy of the target residue (the entropy of the corresponding column in multiple alignment obtained by aligning the target sequence with its sequence homologs) as additional input. The classifier achieves 78% overall accuracy with a correlation coefficient of 0.28, 44% specificity and 41% sensitivity in identifying interface residues. Examination of the predictions in the context of 3-dimensional structures of proteins demonstrates the effectiveness of this method in identifying DNA-binding sites from sequence information. In 33% (56 out of 171) of the proteins, the classifier identifies the interaction sites by correctly recognizing at least half of the interface residues. In 87% (149 out of 171) of the proteins, the classifier correctly identifies at least 20% of the interface residues. This suggests the possibility of using such classifiers to identify potential DNA-binding motifs and to gain potentially useful insights into sequence correlates of protein-DNA interactions.

Conclusion
Naïve Bayes classifiers trained to identify DNA-binding residues using sequence information offer a computationally efficient approach to identifying putative DNA-binding sites in DNA-binding proteins and recognizing potential DNA-binding motifs.
Prognostic significance of cyclooxygenase-2 (COX-2) expression in patients with surgically resectable adenocarcinoma of the oesophagus
Authors: Bhandari Pradeep , Bateman Adrian C , Mehta Raj L , Stacey Bernard SF , Johnson Penny , Cree Ian A , Di Nicolantonio Federica , Patel Praful 
Published: May 2006

Abstract

Background
COX-2 expression in tumour cells has been associated with poor prognosis in gastrointestinal and non-gastrointestinal cancers. The aim of our study was to test the hypothesis that higher levels of COX-2 expression are prognostically related to poor clinico-pathologic features in adenocarcinoma of the oesophagus.

Methods
We reviewed the records of 100 consecutive patients undergoing resection for adenocarcinoma of the oesophagus to collect data on T-stage, N-stage, tumour recurrence and survival. T & N-stage was further confirmed by histological examination. COX-2 protein expression was assessed by immunohistochemistry in all patients and COX-2 m-RNA expression was measured by quantitative RT-PCR in a small group of patients.

Results
Higher levels of COX-2 expression were associated with higher T stage (p = 0.008), higher N stage (p = 0.049), increased risk of tumour recurrence (p = 0.01) and poor survival (p = <0.001). A COX-2 score of >200 was associated with a median survival of 10 months compared to 26 months with a score of <200 (p = <0.001).

Conclusion
Higher levels of COX-2 expression are associated with poor clinico-pathologic features and poor survival in patients with oesophageal adenocarcinoma.
Particulate delivery systems for vaccines: what can we expect?
Authors: Bramwell Vincent W , Perrie Yvonne 
Published: May 2006

Abstract
In our attempts to thwart the unwanted attentions of microbes by prophylactic and therapeutic vaccination, the knowledge of interactions at the molecular level may prove to be an invaluable asset. This article examines how particulate delivery systems such as liposomes and polymer micro-spheres can be applied in the light of recent advances in immunological understanding. Some of the biological interactions of these delivery systems are discussed with relevance for antigen trafficking and molecular pathways of immunogenicity and emphasis on the possible interaction of liposomal components. In particular, traditional concepts such as antigen protection, delivery to antigen presenting cells and depot formation remain important aspects, whilst the inclusion of selected co-adjuvants and enhanced delivery of these moieties in conjunction with antigen now has a firm rationale.
An investigation into the adjuvanticity and immunogenicity of zein microspheres being researched as drug and vaccine carriers
Authors: Hurtado-López Pepi , Murdan Sudaxshina 
Published: May 2006

Abstract
We have determined whether zein microspheres could act as vaccine adjuvants i.e. increase the immune responses to co-administered immunogens. Ovalbumin (model antigen)-loaded zein micro-spheres, blank zein microspheres and ovalbumin solution were intramuscularly administered to mice and the sera antibody levels were determined by ELISA. Another group of mice was orally dosed with blank zein microspheres, and serum and faecal antibody levels were determined. As expected, negligible antibody titres were obtained with the ovalbumin solution. Surprisingly, intramuscular administrations of blank zein microspheres elicited high levels of serum IgG which bound to the ovalbumin antigen coated on ELISA microtitre plates. This indicated that anti-zein antibodies had been elicited by blank zein microspheres and that these antibodies were cross-reacting with ovalbumin antigen coated onto ELISA plates. Such cross-reactivity inhibited the determination of the adjuvant activity of zein microspheres, if any. Additional ELISA assays, where zein was used as the coating antigen, confirmed the generation of anti-zein antibodies by blank zein microspheres i.e. zein microspheres were immunogenic following intramuscular administration. Upon oral administration of blank zein microspheres, serum IgG levels remained low but intestinal IgA levels increased following booster doses i.e. systemic tolerance, but not mucosal tolerance, to oral zein particles was achieved. Zein microspheres were immunogenic when administered intramuscularly and orally.
The preparation of liposomes using compressed carbon dioxide: strategies, important considerations and comparison with conventional techniques
Authors: Bridson R H , Santos R C D , Al-Duri B , McAllister S M , Robertson J , Alpar H O 
Published: May 2006

Abstract
Numerous strategies are currently available for preparing liposomes, although no single method is ideal in every respect. Two methods for producing liposomes using compressed carbon dioxide in either its liquid or supercritical state were therefore investigated as possible alternatives to the conventional techniques currently used. The first technique used modified compressed carbon dioxide as a solvent system. The way in which changes in pressure, temperature, apparatus geometry and solvent flow rate affected the size distributions of the formulations was examined. In general, liposomes in the nano-size range with an average diameter of 200 nm could be produced, although some micron-sized vesicles were also present. Liposomes were characterized according to their hydrophobic drug-loading capacity and encapsulated aqueous volumes. The latter were found to be higher than in conventional techniques such as high-pressure homogenization. The second method used compressed carbon dioxide as an antisolvent to promote uniform precipitation of phospholipids from concentrated ethanolic solutions. Finely divided solvent-free phospholipid powders of saturated lipids could be prepared that were subsequently hydrated to produce liposomes with mean volume diameters of around 5 μm.
A comparative study of cationic liposome and niosome-based adjuvant systems for protein subunit vaccines: characterisation, environmental scanning electron microscopy and immunisation studies in mice
Authors: Vangala Anil , Kirby Daniel , Rosenkrands Ida , Agger Else Marie , Andersen Peter , Perrie Yvonne 
Published: May 2006

Abstract
Vesicular adjuvant systems composing dimethyldioctadecylammonium (DDA) can promote both cell-mediated and humoral immune responses to the tuberculosis vaccine fusion protein in mice. However, these DDA preparations were found to be physically unstable, forming aggregates under ambient storage conditions. Therefore there is a need to improve the stability of such systems without undermining their potent adjuvanticity. To this end, the effect of incorporating non-ionic surfactants, such as 1-monopalmitoyl glycerol (MP), in addition to cholesterol (Chol) and trehalose 6,60-dibehenate (TDB), on the stability and efficacy of these vaccine delivery systems was investigated. Differential scanning calorimetry revealed a reduction in the phase transition temperature (Tc) of DDA-based vesicles by ∼12°C when MP and cholesterol (1:1 molar ratio) were incorporated into the DDA system. Transmission electron microscopy (TEM) revealed the addition of MP to DDA vesicles resulted in the formation of multi-lamellar vesicles. Environmental scanning electron microscopy (ESEM) of MP-Chol-DDA-TDB (16:16:4:0.5 μmol) indicated that incorporation of antigen led to increased stability of the vesicles, perhaps as a result of the antigen embedding within the vesicle bilayers. At 4°C DDA liposomes showed significant vesicle aggregation after 28 days, although addition of MP-Chol or TDB was shown to inhibit this instability. Alternatively, at 25°C only the MP-based systems retained their original size. The presence of MP within the vesicle formulation was also shown to promote a sustained release of antigen in-vitro. The adjuvant activity of various systems was tested in mice against three subunit antigens, including mycobacterial fusion protein Ag85B-ESAT-6, and two malarial antigens (Merozoite surface protein 1, MSP1, and the glutamate rich protein, GLURP). The MP-and DDA-based systems induced antibody responses at comparable levels whereas the DDA-based systems induced more powerful cell-mediated immune responses.
Evaluation in melanoma-bearing mice of an etoposide derivative associated to a cholesterol-rich nanoemulsion
Authors: Prete Ana C Lo , Maria Durvanei A , Rodrigues Dé bora G , Valduga Claudete J , Ibañez Olga C M , Maranhão Raul C 
Published: May 2006

Abstract
A cholesterol-rich nanoemulsion (LDE) may be used as a vehicle to target antineoplastic drugs against cancer cells. The association of an etoposide derivative to LDE is stable and retains the cytotoxic activity of etoposide. We have evaluated the toxicity and antitumoral action of this new preparation in-vivo. Melanoma-bearing mice and control mice were administered LDE-etoposide oleate or commercial etoposide, either with or without radioactive labelling. The maximum tolerated dose (MTD), tissue distribution, plasma decay curves, pharmacokinetic parameters and antitumoral activity were determined. Association to LDE drastically reduced the drug toxicity, since MTD was approximately five-fold greater than in commercial etoposide. LDE-etoposide oleate was concentrated four-fold in the tumour compared with the normal adjacent tissues, was removed faster from plasma in tumour-bearing mice than in controls, and remained in the bloodstream longer than commercial etoposide. The tumour growth inhibition rate and survival were greater in animals treated with LDE-etoposide oleate compared with commercial etoposide. However, increasing the dose from 17 to 85 μM kg−1 did not result in further improvement of the antitumour action. The incorporation of etoposide oleate to LDE resulted in markedly reduced toxicity and superior antitumoral activity. LDE-etoposide oleate is a promising new weapon for cancer treatment.