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1.
Eur J Radiol ; 126: 108909, 2020 May.
Article En | MEDLINE | ID: mdl-32145600

PURPOSE: To assess the dose-normalized iodine contrast-to-noise-ratio (CNRD) improvement and contrast media reduction potential obtained with photon-counting (PC) CT compared to conventional energy-integrating (EI) CT as a function of patient size and tube voltage. METHOD: Images of a semi-anthropomorphic phantom of different sizes (small, medium, large) equipped with vials containing different iodine concentrations were acquired at the SOMATOM CounT prototype CT system using tube voltages of 80 kV-140 kV. CNRD is evaluated in reconstructions obtained using the EI detector, the PC detector using a single bin, and in reconstructions obtained by statistically optimally weighting acquisitions with two bins. Iodine CNRD improvements, potential dose reduction and the potential contrast media volume reduction are reported. RESULTS: In general, iodine CNRD improvement increases with increasing tube voltage for all patient sizes. In particular, if only one energy bin is used, the CNRD improvement is up to 30 % (small: 10 %, medium: 18 %, large: 30 %) and up to 37 % if an optimal weighting of two bins is performed (small: 13 %, medium: 25 %, large: 37 %) which is equivalent to the potential contrast media volume reduction. The improved iodine CNRD of PC compared to EI may allow for a potential radiation dose reduction of up to 46 %. CONCLUSIONS: All patients' iodine contrast at given x-ray dose, and particularly medium and large sized patients acquired at higher tube voltages, may benefit from photon-counting CT. The iodine contrast improvement can be used to reduce patient dose or to reduce the amount of contrast agent that is administered.


Contrast Media , Phantoms, Imaging , Radiation Dosage , Radiographic Image Enhancement/methods , Tomography, X-Ray Computed/methods , Whole-Body Counting/methods , Iodine , Photons
2.
Int J Cosmet Sci ; 39(6): 580-588, 2017 Dec.
Article En | MEDLINE | ID: mdl-28699157

OBJECTIVE: Organosiloxanes are prevalent in personal care products (PCPs) due to the desired properties they impart in the usage and application of such products. However, the European Chemical Agency (ECHA) has recently published restriction proposals on the amount of two cyclic siloxanes, octamethylcyclotetrasiloxane (D4) and decamethylcyclotetrasiloxane (D5), allowed in wash off products such as shampoos and conditioners which are discharged down the drain during consumer use. This legislation will require that reliable analytical methods are available for manufacturers and government agencies to use in documenting compliance with the restrictions. This article proposes a simple analytical method to enable accurate measurement of these compounds down to the circa 0.1 weight per cent level in PCPs. METHODS: Although gas chromatography methods are reported in the literature for quantitation of D4 and D5 in several matrices including PCPs, the potential for generation of false positives due to contamination, co-elution and in situ generation of cyclic volatile methylsiloxanes (cVMS) is always present and needs to be controlled. This report demonstrates the applicability of using a combination of emulsion break, liquid-liquid extraction and silylation sample preparation followed by GC-FID analysis as a suitable means of analysing PCPs for specific cVMS. RESULTS: The reliability and limitations of such methodology were demonstrated through several round-robin studies conducted in the laboratories of a consortium of silicone manufacturers. In addition, this report presents examples of false positives encountered during development of the method and presents a comparative analysis between this method and a published QuEChERS sample preparation procedure to illustrate the potential for generation of false positives when an inappropriate approach is applied to determination of cVMS in personal care products. CONCLUSION: This report demonstrates that an approach to determine cVMS levels in personal care products is to perform an emulsion break on the sample, isolate the non-polar phase from the emulsion break and treat with a silylation reagent to abate potential in situ formation of cyclics during the course of GC-FID analysis. Round-robin studies conducted in laboratories representing multiple siloxane manufacturers demonstrated the reliability of the GC-FID method when measuring cVMS in PCPs down to circa 0.1%.


Chromatography, Gas/methods , Cosmetics/chemistry , Siloxanes/analysis , Reproducibility of Results , Volatilization
3.
Bull Entomol Res ; 107(2): 268-280, 2017 Apr.
Article En | MEDLINE | ID: mdl-27809942

Understanding herbivore diversity both at the species and genetic levels is a key to effective pest management. We examined moth samples from multiple locations from a major apple growing region in China. For specimen collection, we used a pheromone trap designed to attract Grapholita molesta (Busck) (Lepidoptera: Tortricidae). Surprisingly, we found a second species captured at high proportions. Its external morphology (e.g., male genitalia and forewing coloration) was the same as for Grapholita funebrana Treitschke (Lepidoptera: Tortricidae) specimens from Europe. However, the barcode sequence of the mitochondrial gene cytochrome oxidase I (COI) diverged markedly between specimens from China and Europe, and the genetic distance value between the specimens from the two regions as estimated using the Juke-Cantor (JC) model amounted to 0.067. These morphological and molecular findings together point to a cryptic species in G. funebrana from China. Further molecular analyses based on COI and COII genes revealed its extremely high genetic diversity, indicating that the origin of this species includes the sampling region. Moreover, molecular data suggest that this species passed through a recent population expansion. This is the first report on a cryptic species in G. funebrana, as well as the first report on its genetic diversity.


Food Chain , Genetic Variation , Insect Proteins/genetics , Moths/genetics , Animals , China , Electron Transport Complex IV/genetics , Electron Transport Complex IV/metabolism , Genetic Speciation , Genitalia, Male/anatomy & histology , Insect Proteins/metabolism , Male , Mitochondrial Proteins , Moths/anatomy & histology , Phylogeny , Population Dynamics , Sequence Analysis, DNA , Sympatry
4.
Neurogastroenterol Motil ; 27(1): 128-34, 2015 Jan.
Article En | MEDLINE | ID: mdl-25482042

BACKGROUND: Although essential, many medical practices are unable to adequately support irritable bowel syndrome (IBS) patient self-management. Web-based programs can help overcome these barriers. METHODS: We developed, assessed, and refined an integrated IBS self-management program (IBS Self-care). We then conducted a 12-week pilot test to assess program utilization, evaluate its association with patients' self-efficacy and quality of life, and collect qualitative feedback to improve the program. KEY RESULTS: 40 subjects with generally mild IBS were recruited via the Internet to participate in a 12-week pilot study. Subjects found the website easy to use (93%) and personally relevant (95%), and 90% would recommend it to a friend. Self-rated IBS knowledge increased from an average of 47.1 on a 100-point VAS scale (SD 22.1) at baseline to 77.4 (SD: 12.4) at week 12 (p < 0.0001). There were no significant changes in patient self-efficacy (Patient Activation Measure) or quality of life (IBS -Quality of Life Scale). CONCLUSIONS & INFERENCES: The IBS Self-Care program was well received by users who after 12 weeks reported improved knowledge about IBS, but no significant changes in self-efficacy or quality of life. If applied to the right population, this low cost solution can overcome some of the deficiencies of medical care and empower individuals to better manage their own IBS.


Health Knowledge, Attitudes, Practice , Internet , Irritable Bowel Syndrome/prevention & control , Self Care/methods , Adolescent , Adult , Aged , Female , Health Status Indicators , Humans , Male , Middle Aged , Pilot Projects , Young Adult
5.
J Chem Ecol ; 40(2): 136-49, 2014 Feb.
Article En | MEDLINE | ID: mdl-24500734

Compensation growth and chemical defense are two components of plant defense strategy against herbivores. In this study, compensation growth and the response of primary and secondary metabolites were investigated in Brassica rapa plants subjected to infestation by two herbivores from contrasting feeding guilds, the phloem-feeding aphid Brevicoryne brassicae and the leaf-feeding caterpillar Pieris brassicae. These specialist herbivores were used at two different densities and allowed to feed for seven days on a young caged leaf. Changes in growth rates were assessed for total leaf area and bulb mass, whereas changes in primary and secondary metabolites were evaluated in young and mature leaves, roots, and bulbs. Mild stress by caterpillars on young plants enhanced mean bulb mass and elicited a contrasting regulation of aliphatic and indolic glucosinolates in the leaves. In contrast, mild stress by aphids enhanced leaf growth and increased glucosinolate concentrations in the bulb, the most important storage organ of B. rapa. A similar mild stress by either herbivore to older plants did not alter plant growth parameters or concentrations of the metabolites analyzed. In conclusion, Brassica plant growth was either maintained or enhanced under mild herbivore stress, and defense patterns differed strongly in response to herbivore type and plant development stage. These results have implications for the understanding of plasticity in plant defenses against herbivores and for the management of Brassica rapa in agroecosystems.


Aphids/physiology , Brassica/physiology , Brassica/parasitology , Butterflies/physiology , Herbivory , Animals , Brassica/growth & development , Female , Glucosinolates/metabolism
6.
Int Endod J ; 47(8): 769-75, 2014 Aug.
Article En | MEDLINE | ID: mdl-24246167

AIM: To evaluate the cytotoxic effects of triple antibiotic paste (TAP), double antibiotic paste (DAP), minocycline and calcium hydroxide and their influence on cytokine mRNA expression levels on human periodontal ligament (HPDL) fibroblasts. METHODOLOGY: Triple antibiotic paste, DAP and Ca(OH)2 test samples were immersed in culture medium and incubated at 37 °C for 24 and 48 h. HPDL cells were seeded at a density of 2 × 10(4) cells and exposed to either culture media (negative control), 0.1% SDS (positive control), 24- or 48-h elutes of each test material and incubated for 24 h. A multiparametric cytotoxicity assay kit (XTT, NR and CVDE) was used to evaluate the cytotoxic effects of each test material. Results were analysed using an ELISA plate reader and light absorbances of 450 and 530 nm as references. Cytokine mRNA expression levels in HPDL cells treated with the materials were also investigated using real-time PCR. Expression levels were calculated using the comparative 2(-ΔΔCt) method. Statistical analyses included anova followed by Bonferroni correction. RESULTS: Triple antibiotic paste and minocycline were the most cytotoxic materials when compared with DAP and Ca(OH)2 in all three (XTT, NR and CVDE) assays (P < 0.0001). No significant differences (P > 0.05) were found for cytokine gene expression levels after exposure to 24- or 48-h elutes of any of the materials except for IL6, which had significantly higher mRNA levels with the 24-h TAP elute (P < 0.01). CONCLUSION: Ca(OH)2 had a minimal effect on cell viability and cytokine production. The TAP showed deleterious effects on HPDL viability and increased expression of the pro-inflammatory cytokine IL6.


Anti-Bacterial Agents/pharmacology , Periodontal Ligament/drug effects , Cells, Cultured , Cytokines/genetics , Cytokines/metabolism , Fibroblasts/drug effects , Humans , Periodontal Ligament/cytology , Periodontal Ligament/metabolism , RNA, Messenger/genetics
7.
J Evol Biol ; 26(11): 2321-30, 2013 Nov.
Article En | MEDLINE | ID: mdl-23981249

Nongenetic parental effects may affect offspring phenotype, and in species with multiple generations per year, these effects may cause life-history traits to vary over the season. We investigated the effects of parental, offspring developmental and offspring adult temperatures on a suite of life-history traits in the globally invasive agricultural pest Grapholita molesta. A low parental temperature resulted in female offspring that developed faster at low developmental temperature compared with females whose parents were reared at high temperature. Furthermore, females whose parents were reared at low temperature were heavier and more fecund and had better flight abilities than females whose parents were reared at high temperature. In addition to these cross-generational effects, females developed at low temperature had similar flight abilities at low and high ambient temperatures, whereas females developed at high temperature had poorer flight abilities at low than at high ambient temperature. Our findings demonstrate a pronounced benefit of low parental temperature on offspring performance, as well as between- and within-generation effects of acclimation to low temperature. In cooler environments, the offspring generation is expected to develop more rapidly than the parental generation and to comprise more fecund and more dispersive females. By producing phenotypes that are adaptive to the conditions inducing them as well as heritable, cross-generational plasticity can influence the evolutionary trajectory of populations. The potential for short-term acclimation to low temperature may allow expanding insect populations to better cope with novel environments and may help to explain the spread and establishment of invasive species.


Flight, Animal , Moths/physiology , Temperature , Adaptation, Physiological , Animals , Breeding , Female , Larva/growth & development , Larva/physiology , Male , Moths/growth & development , Phenotype
8.
J Chem Ecol ; 39(5): 653-65, 2013 May.
Article En | MEDLINE | ID: mdl-23609163

Plants growing under elevated CO2 concentration may acclimate by modifying chemical traits. Most studies have focused on the effects of environmental change on plant growth and productivity. Potential effects on chemical traits involved in resistance, and the consequences of such effects on plant-insect interactions, have been largely neglected. Here, we evaluated the performance of two Brassica specialist herbivores from contrasting feeding guilds, the leaf-feeding Pieris brassicae and the phloem-feeding Brevicoryne brassicae, in response to potential CO2-mediated changes in primary and major secondary metabolites (glucosinolates) in Brassica oleracea. Plants were exposed to either ambient (400 ppm) or elevated (800 ppm) CO2 concentrations for 2, 6, or 10 weeks. Elevated CO2 did not affect primary metabolites, but significantly increased glucosinolate content. The performance of both herbivores was significantly reduced under elevated CO2 suggesting that CO2-mediated increases in constitutive defense chemistry could benefit plants. However, plants with up-regulated defenses could also be subjected to intensified herbivory by some specialized herbivores, due to a chemically-mediated phagostimulatory effect, as documented here for P. brassicae larvae. Our results highlight the importance of understanding acclimation and responses of plants to the predicted increases in atmospheric CO2 concentrations and the concomitant effects of these responses on the chemically-mediated interactions between plants and specialized herbivores.


Aphids/physiology , Brassica/drug effects , Butterflies/physiology , Carbon Dioxide/pharmacology , Glucosinolates/metabolism , Herbivory/physiology , Animals , Brassica/metabolism
9.
J Chem Ecol ; 39(3): 418-29, 2013 Mar.
Article En | MEDLINE | ID: mdl-23440443

Insect herbivores that have more than one generation per year and reproduce on different host plants are confronted with substantial seasonal variation in the volatile blends emitted by their hosts. One way to deal with such variation is to respond to a specific set of compounds common to all host plants. The oriental fruit moth Cydia (=Grapholita) molesta is a highly damaging invasive pest. The stone fruit peach (Prunus persica) is its primary host, whereas pome fruits such as pear (Pyrus communis) are considered secondary hosts. In some parts of their geographic range, moth populations switch from stone to pome fruit orchards during the growing season. Here, we tested whether this temporal switch is facilitated by female responses to plant volatiles. We collected volatiles from peach and pear trees in situ and characterized their seasonal dynamics by gas chromatography-mass spectrometry. We also assessed the effects of the natural volatile blends released by the two plant species on female attraction by using Y-tube olfactometry. Finally, we related variations in volatile emissions to female olfactory responses. Our results indicate that the seasonal host switch from peach to pear is facilitated by the changing olfactory effect of the natural volatile blends being emitted. Peach volatiles were only attractive early and mid season, whereas pear volatiles were attractive from mid to late season. Blends from the various attractive stages shared a common set of five aldehydes, which are suggested to play an essential role in female attraction to host plants. Particular attention should be given to these aldehydes when designing candidate attractants for oriental fruit moth females.


Behavior, Animal/drug effects , Laboratories , Moths/drug effects , Odorants/analysis , Rosaceae/chemistry , Seasons , Volatile Organic Compounds/pharmacology , Animals , Biological Assay , Female , Prunus/chemistry , Pyrus/chemistry , Trees/chemistry , Volatile Organic Compounds/chemistry
10.
Behav Genet ; 42(4): 687-97, 2012 Jul.
Article En | MEDLINE | ID: mdl-22528142

Lepidopteran insects are major pests of agricultural crops, and mated female moths exploit plant volatiles to locate suitable hosts for oviposition. We investigated the heritability of odor-guided host location behavior and fecundity in the cosmopolitan oriental fruit moth Grapholita (Cydia) molesta, an oligophagous herbivore that attacks fruit trees. We used a full-sib/half-sib approach to estimate the heritability and the genetic correlation between these two traits. Results document a considerable genetic basis for olfactory attraction of females (h ( 2 ) = 0.37 ± 0.17) and their fecundity (h ( 2 ) = 0.32 ± 0.13), as well as a genetic trade-off between female attraction and fecundity (r ( g ) = -0.85 ± 0.21). These estimations were empirically corroborated by comparing two strains maintained in the laboratory for different numbers of generations. The long-term reared strain lost its olfactory discrimination ability but achieved significantly higher fecundity compared with the short-term reared strain. Our results highlight that genetic studies are relevant for understanding the evolution of odor-guided behavior in herbivore insects and for judging the promise of pest management strategies involving behavioral manipulation with plant volatiles.


Behavior, Animal , Herbivory/genetics , Moths/genetics , Odorants , Smell , Animals , Female , Fertility/genetics , Prunus , Volatile Organic Compounds
11.
J Exp Biol ; 213(Pt 19): 3388-97, 2010 Oct 01.
Article En | MEDLINE | ID: mdl-20833933

Ratios of compounds in host plant odors fluctuate with the phenological stage of the plant. In the present study, we investigated the effect of changing ratios of host plant volatile constituents on herbivore insect attraction and olfactory information processing. We tested a synthetic mixture of bioactive peach shoot volatiles with different concentrations of one of the mixture constituents, benzonitrile, on oriental fruit moth Cydia (=Grapholita) molesta females. Y-tube olfactometer bioassays showed that female attraction to the mixture was maintained while increasing the benzonitrile level up to 100 times. Further increases led to behaviorally ineffective mixtures. Then, we recorded odor-evoked neural activity patterns in the antennal lobes, the main olfactory center of the brain, using calcium imaging. Benzonitrile-containing mixtures elicited strong activation in two glomeruli, which were found to process mixture-related information in specific ways. Activation in one glomerulus directly paralleled behavioral effects of the different ratios tested whereas a deviating pattern was noted in the other glomerulus. Our results indicate that the ratio of constituents in a volatile mixture can be varied to a certain degree without reducing female attraction. Thus, volatile blends in nature might vary quantitatively within a certain range without affecting odor-guided host location. Neurophysiological results showed that the processing of mixture-related information inside the antennal lobes is not uniform across glomeruli. Thus, final processing of this information probably takes place in higher-order brain centers.


Moths/physiology , Plants/chemistry , Plants/parasitology , Animals , Arthropod Antennae/drug effects , Arthropod Antennae/innervation , Arthropod Antennae/physiology , Behavior, Animal/drug effects , Female , Host-Parasite Interactions/physiology , Moths/drug effects , Nitriles/pharmacology , Odorants , Pheromones/chemistry , Pheromones/pharmacology , Prunus/chemistry , Prunus/parasitology , Volatile Organic Compounds/chemistry , Volatile Organic Compounds/pharmacology , Volatilization
12.
Mol Ecol ; 19(11): 2336-45, 2010 Jun.
Article En | MEDLINE | ID: mdl-20465585

Inbreeding occurs in numerous animal and plant species. In haplodiploid hymenopterans with the widespread single locus complementary sex determination, the frequency of diploid males, which are produced at the expense of females, is increased under inbreeding. Diploid males in species of bees, ants and wasps are typically either unviable or effectively sterile and thus impose a severe genetic load on populations. However, a recent study indicated that diploid males can be reproductive in the gregarious parasitoid wasp Cotesia glomerata, effectively reducing the diploid male load. To understand the role of inbreeding as a potential selective pressure towards the evolution of diploid male fertility, we genotyped specimens collected in the field at four locations using microsatellite markers to estimate the ratio of sibling matings under natural conditions. Results show that more than half of all matings involved siblings. We argue that the frequent occurrence of inbreeding has driven the evolution of diploid male fertility.


Inbreeding , Sexual Behavior, Animal , Wasps/genetics , Alleles , Animals , Bayes Theorem , Cluster Analysis , Diploidy , Evolution, Molecular , Female , Genotype , Male , Microsatellite Repeats , Models, Genetic , Reproduction/genetics , Selection, Genetic , Sequence Analysis, DNA
13.
Aliment Pharmacol Ther ; 32(4): 513-21, 2010 Aug.
Article En | MEDLINE | ID: mdl-20497137

BACKGROUND: Irritable bowel syndrome is an extremely common and costly condition. Because there is no cure, patients must be supported to manage their own condition. AIM: To assess systematically the interventions used to support irritable bowel syndrome patient self-management. METHODS: A search of PubMed, EMBASE, CINAHL and PsycINFO was performed to identify all studies that involved self-management support interventions for irritable bowel syndrome. Studies that compared the self-management-related intervention to a control group were included. RESULTS: Eleven studies that involved a total of 1657 patients were included. For nearly all studies, the intervention was associated with statistically significant benefits. However, across studies there was significant heterogeneity in terms of sample size, diagnostic criteria, study setting, study design, primary outcome, statistical analyses and study quality. Therefore, individual study results could not be statistically combined. CONCLUSIONS: Many self-management support interventions appear benefit patients with irritable bowel syndrome. However, studies were limited by methodological flaws. Furthermore, feasibility in 'real world' clinical practice is uncertain. Thus, practical self-management interventions that can be applied across various clinical settings should be developed, and then tested in well-designed clinical trials.


Irritable Bowel Syndrome/therapy , Self Care/methods , Books , Cognitive Behavioral Therapy/methods , Humans , Hypnosis , Patient Education as Topic , Self-Help Groups
14.
Mol Ecol Resour ; 10(6): 1034-7, 2010 Nov.
Article En | MEDLINE | ID: mdl-21565113

This study examined cross-species amplification of 33 microsatellite markers, previously developed for Cydia pomonella, in three related fruit moth species of the same tribe (Grapholitini), namely Grapholita molesta, Grapholita funebrana and Grapholita lobarzewskii. Eight microsatellite loci yielded polymorphic products for G. molesta, nine for G. funebrana and 11 for G. lobarzewskii. At all these loci, the number of alleles ranged between four and 11 in G. molesta, and between four and nine in G. funebrana and G. lobarzewskii each. The successful cross-amplified loci can be used for research on population genetics and gene flow of the three target species.

15.
Bull Entomol Res ; 100(1): 75-85, 2010 Feb.
Article En | MEDLINE | ID: mdl-19366473

Little is known about genetic differentiation and gene flow in populations of insect species that have a high genetic variability in dispersal but lack morphologically visible morphs that disperse. These characteristics apply to the codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae), a major pest of fruits and nuts. Larvae were collected from three orchards each of pome fruits, stone fruits and nut trees in a major fruit growing area of Switzerland (Valais) and from six further (mainly apple) orchards throughout this country. Nine microsatellite loci were used to investigate genetic differentiation and the amount of gene flow among the sampled populations. All the loci were shown to be polymorphic in all populations. The number of alleles ranged from five to 15 over nine loci for the 15 populations. Significant genetic differentiation was noted among the populations from apple, apricot and walnut in the Valais region. Furthermore, among the eight populations sampled from apple in different geographic regions throughout Switzerland, AMOVA and pairwise FST analysis revealed significant population genetic differentiation even between populations collected from orchards 10 km apart. These results indicate that a distinct prevailing characteristic, in the present case the sedentary behaviour of the moth, can shape population architecture.


Demography , Genetic Variation , Genetics, Population , Moths/genetics , Analysis of Variance , Animals , Gene Flow/genetics , Microsatellite Repeats/genetics , Switzerland
16.
Aliment Pharmacol Ther ; 31(6): 666-75, 2010 Mar.
Article En | MEDLINE | ID: mdl-20015103

BACKGROUND: Previous studies on coeliac disease (CD)-related quality of life (QOL) have been limited by their use of a 'generic' rather than coeliac disease-specific assessment instruments. AIM: To develop and psychometrically validate a new coeliac disease-specific instrument, the CD-QOL. METHODS: Through a series of focus groups, we elicited items from patients that related to the specific nature of their disease and its impact on their basic needs. Through expert review, cognitive debriefing with patients and pilot testing, a scale was developed, refined and administered to 387 patients on a gluten-free diet from both community-based support groups and a tertiary care referral centre. Finally, a formal validation study was conducted to assess the psychometric properties of the CD-QOL. RESULTS: The final CD-QOL has 20 items across four clinically relevant subscales (Limitations, Dysphoria, Health Concerns, and Inadequate Treatment). The CD-QOL has high internal consistency, reliability, and psychometric validation indicates both convergent and discriminate validity. CONCLUSIONS: The CD-QOL is a reliable and valid measure of coeliac disease related QOL. As a new disease-specific instrument, it is likely to be a useful tool for evaluating patients with this disorder.


Celiac Disease/psychology , Psychometrics/standards , Quality of Life , Surveys and Questionnaires/standards , Adolescent , Adult , Aged , Aged, 80 and over , Female , Focus Groups , Health Status , Humans , Male , Middle Aged , Reproducibility of Results
17.
J Econ Entomol ; 102(6): 2209-16, 2009 Dec.
Article En | MEDLINE | ID: mdl-20069850

The fruit pests Cydia pomonella (L.), Grapholita molesta (Busck), Grapholita funebrana Treitschke, and Grapholita lobarzewskii Nowicki (all Lepidoptera: Tortricidae) are sympatric in Europe, and some of them are expanding their distribution range worldwide by continuous invasion into new areas. Identification of the small larvae by morphological characters and damage symptoms is difficult, and many misidentifications among these tortricids of the tribe Grapholitini are reported. In the current study, the species were separated using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analyses. Samples were obtained from different countries and continents, and the mitochondrial cytochrome oxidase subunit I (COI) fragments of one individual per species and geographical site were sequenced. Based on the alignments of the amplified COI sequences, the PCR-RFLP method was established with 42 individuals and successfully validated using a total of 122 individuals of the four species. Results document that this method allows for discrimination of larvae, pupae, and adult specimens of all four species and can be used for a rapid and reliable identification of C. pomonella, G. molesta, G. funebrana, and G. lobarzewskii. Moreover, it can easily be expanded to other internal tortricid fruit feeder species that occur on different continents.


Electron Transport Complex IV/genetics , Moths/classification , Animals , DNA Restriction Enzymes , Europe , Fruit/parasitology , Genes, Insect , Malus/parasitology , Moths/genetics , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Prunus/parasitology , Sequence Alignment , Sequence Analysis, DNA
18.
Neurogastroenterol Motil ; 19(8): 630-7, 2007 Aug.
Article En | MEDLINE | ID: mdl-17640177

Among patients with irritable bowel syndrome (IBS) enrolled in clinical trials of conventional medical therapy, the placebo response rate is high. IBS patients also frequently use complementary and alternative medicine (CAM), which may act through an 'enhanced placebo effect'. The purpose of this study was to estimate the magnitude of the placebo response rate in CAM trials for IBS and to identify factors that influence this response. We performed a systematic review and meta-analysis of randomized, placebo-controlled clinical trials of CAM therapies for IBS identified from MEDLINE/EMBASE/PsychLIT databases from 1970 to 2006. Placebo and active treatment response rates for global symptom improvement were assessed. Nineteen studies met the inclusion criteria. The pooled estimate of the placebo response rate was 42.6% (95% confidence interval, 38.0-46.5%). Significant heterogeneity existed across trials (range 15.0-72.2%, P < 0.00001). Higher placebo response rates correlated with a longer duration of treatment (r = 0.455, P = 0.05) and a greater number of office visits (r = 0.633, P = 0.03). Among IBS patients in CAM trials, the placebo response rate is high. That this rate is similar in magnitude to that seen in conventional medicine trials suggests that the placebo response is independent of the type of therapy used and that it is not particularly 'enhanced' in CAM trials.


Complementary Therapies , Irritable Bowel Syndrome/therapy , Placebo Effect , Humans
19.
Heredity (Edinb) ; 96(6): 487-92, 2006 Jun.
Article En | MEDLINE | ID: mdl-16622470

The parasitoid Cotesia glomerata usually produces female-biased sex ratios in the field, which are presumably caused by inbreeding and local mate competition (LMC); yet, sibling mating increases the production of males, leading to the male-biased sex ratio of broods in the laboratory. Previous studies have suggested that the sex allocation strategy of C. glomerata is based on both partial LMC in males and inbreeding avoidance in females. The current study investigated the presence of single-locus complementary sex determination (sl-CSD) as a sex-determining mechanism in this species through inbreeding experiment, cytological examination and microsatellite analysis. Cytological examination detected diploid males in nine of 17 single pairs of sibling mating, thus in agreement with the proportion of matched matings predicted by the sl-CSD model. Sex ratio shifts in these matched sibling matings were consistent with the sl-CSD model with less viable diploid males. The haploid males have a single set of maternal chromosomes (n = 10), whereas diploid males possess a double set of chromosomes (2n = 20). Microsatellite analyses confirmed that diploid males produced from the matched matings inherited segregating genetic materials from both parents. Thus, this study provides the first solid evidence for the presence of sl-CSD as a sex-determining mechanism in the braconid genus Cotesia.


Sex Determination Processes , Wasps/genetics , Animals , Female , Longevity , Male , Metaphase , Microsatellite Repeats , Sexual Behavior, Animal , Spermatocytes/cytology , Wasps/growth & development , Wasps/pathogenicity
20.
Article En | MEDLINE | ID: mdl-16317561

Certain parasitic wasps (Ichneumonidae, Pimplinae) use self-produced vibrations transmitted on plant substrate to locate their immobile concealed hosts (i.e. lepidopteran pupae). This mechanosensory mechanism, called the vibrational sounding, depends both on physical cues of the environment and physical activity of the parasitoid and is postulated to depend on ambient temperature. We analysed the influences of temperature on vibrational sounding by choice experiments using plant-stem models with hidden host mimics in the temperate species Pimpla turionellae. The results show a significant effect of temperature on host-location activity and on the success of this process. Outside an optimum range, the performance of the wasps decreased both at low and high temperatures. Below 10 degrees C and beyond 24 degrees C, the wasps displayed (1) substantial reduction in responsiveness, i.e. proportion of females showing ovipositor insertions, (2) reduction of quantitative activity with ovipositor insertions in the individuals, and (3) reduced precision of mechanosensory host location. Nevertheless, female wasps were able to locate their host over a surprisingly broad range of ambient temperatures which indicates that the wasps are able to compensate for temperature effects on vibrational sounding.


Echolocation/physiology , Host-Parasite Interactions/physiology , Lepidoptera/parasitology , Mechanoreceptors/physiology , Predatory Behavior/physiology , Temperature , Wasps/physiology , Animals , Environment , Female , Pupa/parasitology , Vibration
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