bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of BDNF mRNA in substantia nigra is dependent on target integrity and independent of neuronal activation
Authors: Rite Inmaculada , Venero José L. , Tomás‐Camardiel Mayka , Machado Alberto , Cano Josefina 
Published: October 2003

AbstractWe have analyzed the regulation of brain‐derived neurotrophic factor (BDNF) mRNA expression in the nigrostriatal system following neurotoxin ablation of striatal targets by means of kainate (KA) or quinolinic acid (QA) injections. Loss of nigral target cells in the striatum was accompanied by significant induction of BDNF mRNA levels in the ipsilateral substantia nigra (SN) at 12 and 24 h post lesion. Dual tyrosine hydroxylase (TH) and BDNF mRNA in situ hybridization (ISH) confirmed the dopaminergic nature of the BDNF mRNA expressing cells. Analysis of neuronal activity in terms of cFos mRNA expression demonstrated intense induction of this marker in the ipsilateral SN pars reticulata (SNPR), but not in SN pars compacta. Dual glutamic acid decarboxylse (GAD) and cFos mRNA ISH confirmed this view. Colchicine injections into the medial forebrain bundle to specifically disrupt neuronal trafficking between SN and striatum induced BDNF mRNA levels in the ipsilateral SNPC, thus demonstrating that nigral expression of BDNF mRNA is dependent of striatal target tissue. In addition, we found significant elevations of BDNF in the subthalamic nucleus following striatal excitotoxic lesion, which may bring novel roles of BDNF in the basal ganglia complex.
The effect of parent sex on prey deliveries to fledgling Eurasian Sparrowhawks Accipiter nisus
Authors: Eldegard Katrine , Selås Vidar , Sonerud Geir A. , Steel Christian , Rafoss Trond 
Published: October 2003

The relative contribution of each parent when providing for the fledglings has been recorded in only a few raptor species. We studied prey deliveries by Eurasian Sparrowhawk Accipiter nisus parents to fledglings at seven nests in southern Norway. Parents and young were fitted with radio‐transmitters. Males delivered a larger number of prey to the young than did females throughout the post‐fledging period (on average c. 80% of the deliveries). Two females were never observed to deliver food to the offspring, and their mates apparently raised the young to independence alone. The duration of the post‐fledging period was positively related to per‐capita delivery rate in the late stage.
Comparison of Electrocardiographic Repolarization Patterns between Hypogonad Males and Normal Subjects
Authors: Kirilmaz Ata , Bolu Erol , Kilicaslan Fethi , Erinc Kursad , Uzun Mehmet , Isik Ersoy , Ozata Metin , Ozdemir Caglayan , Demirtas Ertan 
Published: October 2003

Background: There is a significant difference in repolarization on the surface ECG between men and women. The effect of testosterone on repolarization of myocardium may provide a basis for the physiological and pathophysiological importance of these distinctions between sexes. The purpose of this study is to compare the repolarization characteristics of surface ECG in patients with secondary hypogonadotropic hypogonadism to those of healthy men and women. Methods: The study consisted of 45 consecutive patients with the diagnosis of secondary hypogonadotropic hypogonadism (study group) and age‐, weight‐ and height‐matched normal healthy men (n = 35) and women (n = 39) (control group). 12‐lead ECG recordings were obtained and electronic calipers were used for measurements of ECG repolarization variables. ECG variables were compared with those of control groups. Results: J point amplitude (0.12 ± 0.07 vs 0.05 ± 0.05 mV, respectively), T max (0.74 ± 0.28 vs 0.60 ± 0.27 mV, respectively), T wave area (81 ± 36 vs 60 ± 29 mVms, respectively) and T wave descending time (93 ± 16 vs 85 ± 15 ms, respectively) were significantly higher in healthy subjects than hypogonadal men. In comparison with those of healthy women, hypogonad males have higher J point (0.05 ± 0.05 vs 0.02 ± 0.02 mV), taller T wave (0.60 ± 0.27 vs 0.34 ± 0.13 mV), consequently less T wave area (60 ± 29 vs 34 ± 16 mVms), ascending (62 ± 18 vs 53 ± 11) and descending angle (67 ± 17 vs 55 ± 12). Corrected QT was not different among groups. Conclusions: Testosterone deprivation in hypogonadotropic hypogonadism attenuates J point, T wave peak, T wave area, and T wave descending time, but does not reach to the level of those in healthy women. Testosterone has no effect on QT interval in this group of age. Hormone replacement therapy of these patients will provide informative contribution.
Variations of Intrathoracic Amount of Blood as a Reason of ECG Voltage Changes
Authors: Saltykova Marina , Capderou Andre , Atkov Oleg , Gusakov Victor , Konovalov Gennagiy , Voronin Leonid , Kaspranskiy Rustem , Morgun Valeriy , Bailliart Olivier , Cermack Milan , Vaïda Pierre 
Published: October 2003

Background: It is known that electroconduction of intrathoracic organs and tissues significantly influences the ECG voltage. It changes during therapy or exercise test due to redistribution and/or volume variations of blood and body fluids and their electroconductivity variations. This fact must be taken into consideration during interpretation of corresponding ECG. But there are no quantitative estimations of this influence on human ECG. The goals of this study were to estimate the influence of variations of thoracic electroconduction, and heart volume on QRS voltage in humans, due to gravity change. Methods: ECGs of 26 healthy volunteers were analyzed in upright and supine position. Experimental conditions—acute change of gravity—are created in a special aircraft flying on Kepler's parabola trajectory. Each parabola includes phases of normo‐, hypergravity (blood shifts in caudal direction), and microgravity (blood redistributes in cranial direction). Amplitude of QRS in Frank leads in all phases has been analyzed. 2‐D echo studies for six subjects were used for estimation of heart volume change. Results: In an upright position during hypergravity the amplitude of R wave in Z increases in 95% of cases (mean 0.19 mV). During microgravity amplitude of R wave in Z decreases in 95% (mean 0.24 mV). In supine position changes of QRS voltage are not significantly. Conclusion: Blood redistribution during gravity change leads to changes of QRS voltage, which is more expressed and steady on R in Z lead: an average near 0.2 mV. It is due to the balance between two factors: (a) changes of degree of short circuiting by variations in the amount of blood in thorax (b) changes of distance between heart and electrodes as a result of change in the position, form, and volume of the heart.
Multiparasitism of Choristoneura fumiferana by the ichneumonid Tranosema rostrale and the tachinid Actia interrupta: occurrence in the field and outcome of competition under laboratory conditions
Authors: Cusson Michel , Laforge Marlène , Régnière Jacques , Béliveau Catherine , Trudel Diane , Thireau J.‐Claude , Bellemare Guy , Keirstead Natalie , Stolz Don 
Published: October 2003

Abstract Tranosema rostrale (Brishke) (Hymenoptera, Ichneumonidae) and Actia interrupta Curran (Hymenoptera: Tachinidae) are the two endoparasitoids most frequently encountered in low‐density populations of the spruce budworm, Choristoneura fumiferana (Clemens) (Lepidoptera, Tortricidae), in the Quebec City region. Monitoring of attack rates of implanted C. fumiferana larvae at two different study sites suggested the possible existence of competition between the two parasitoids, with A. interrupta seemingly displacing T. rostrale. Here, we show that multiparasitism involving these two species does occur in the field, but at a frequency too low to explain the seasonal pattern of decline in apparent parasitism by T. rostrale that accompanies the rise of A. interrupta attack rates. We also provide preliminary evidence, from laboratory experiments, that A. interrupta has a competitive advantage over T. rostrale and that the success of parasitism by A. interrupta may be enhanced by prior parasitism by T. rostrale under certain conditions, possibly due to the presence of the latter species' polydnavirus. In addition, we describe a PCR‐based method that we developed to help detect the presence of T. rostrale eggs which often escape detection by simple visual examination of the dissected host larvae; DNA sequences specific to the polydnavirus injected by the female wasp at the time of oviposition can be readily amplified from whole host larvae.
Clutch size, development and wing morph differentiation of Melittobia digitata
Authors: Cônsoli Fernando L. , Vinson S.Bradleigh 
Published: October 2003

Abstract Melittobia digitata Dahms (Hymenoptera, Eulophidae) is a wing polymorphic, gregarious ectoparasitoid of bees and wasps. In nature, females of this wasp start to produce their progeny after feeding on the host. The first adults to develop will emerge as short wing morphs (SWM). Mother and daughters will lay eggs in the same hosts, and the following females to develop will emerge as long wing morphs (LWM). We evaluated the effects of the clutch size on the development, egg load, and wing morph differentiation of M. digitata. Developmental time was shorter when insects developed in small clutches, and immature survivorship was reduced in the largest clutch (400 eggs/host). Morph differentiation was also affected by the clutch size. SWMs developed in small clutches (5 and 25 eggs/host) while LWMs in large clutches (200 and 400 eggs/host). However, both morphs developed in intermediate clutches (50 and 100 eggs/clutch), with a decreasing number of SWMs developing with the increase in the clutch. The size and egg load of each morph was affected with the increase in the clutch size, although the forewing length/hind‐tibia length ratio was kept constant for each morph developing from different clutch sizes. Egg load of LWMs was also reduced when compared to the SWMs that developed from the same clutch, although LWMs females were larger (longer tibia length). We discuss the possible mechanisms inducing the morph differentiation in M. digitata, as well as the physiological, behavioral, and ecological changes facing each morph.
Morphology of putative female sex pheromone glands and mating behaviour in Aphidoletes aphidimyza
Authors: van Lenteren Joop C. , Schettino Mauro , Isidoro Nunzio , Romani Roberto , van Schelt Jeroen 
Published: October 2003

AbstractAdult emergence period, sex ratio, female calling behaviour, and the risky mating behaviour of A. aphidimyza in spider webs are described. We provide evidence that A. aphidimyza females produce a sex pheromone and attract males, and we give a description of the location and structure of the supposed pheromone producing glands of A. aphidimyza based on scanning and transmission electron microscopy. This is the first demonstration of occurrence of sex pheromones for a zoophagous species of Cecidomyiidae. The question is discussed why A. aphidimyza is using spider webs for mating.
Ancestral feeding and survival of offspring in European corn borer
Authors: Andow D.A. 
Published: October 2003

AbstractExperiments were conducted to evaluate the influence of ancestral adult feeding by European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae), on larval survival in the field and neonate movement behavior in laboratory. Larval survival was higher when either the grandparental or parental generation had fed, but the feeding sites of the surviving larvae were not affected by ancestral feeding condition. This is the first evidence that grandparental feeding could influence larval survival in the field. Larval movement was observed in the laboratory. Silking speed of neonates was faster when either grandparents or parents had fed, while walking speed was faster only when parents had fed. No broad‐sense genetic correlation was found between silking speed and walking speed. Broad‐sense heritability among feeding histories were not significant for silking speed, but was significantly greater than zero for walking speed when grandparents fed and parents did not. These intergenerational effects could induce complex population dynamics in this species.
Phenological analysis of spring colonisation of apple trees by Anthonomus pomorum
Authors: Toepfer Stefan , Gu Hainan , Dorn Silvia 
Published: October 2003

AbstractAdult apple blossom weevils, Anthonomus pomorum (L.) (Coleoptera: Curculionidae), leave their overwintering sites within and outside orchards to colonise apple trees in early spring. This study was conducted to characterize the temporal pattern of spring colonization of apple trees by overwintered weevils in relation to climatic conditions and apple bud stages, based on multiple mark‐release‐recapture experiments and field observations of foraging activities of weevils. The process of spring colonization of apple trees by overwintered weevils was related to thermal time totals above 0 °C. The dispersal into orchards initiated when the thermal time totals reached 161±27 (s.d.) degree‐days (DD) calculated from January 1, or 117±16 DD from February 1. The daily dispersal speed of individual weevils within orchards was determined primarily by the maximum daily temperature, whereas crawling, feeding, and mating activities of weevils on apple trees were influenced by the mean evening temperature between 18:00 and 22:00 hours. On the other hand, the spring colonization of overwintered weevils was not synchronized with any specific apple bud stage, though the level of female foraging and reproductive activities on apple trees was related to apple bud stages. The overwintered weevils initiated dispersal into orchards over a wide range of bud developmental stages from little silver greenish tip B (51) to the mouse‐ear stage C3 (54). These findings are discussed in relation to the ecology and pest management of this insect.
Whorl and pollen‐shed stage application of Beauveria bassiana for suppression of adult western corn rootworm
Authors: Bruck Denny J. , Lewis Leslie C. 
Published: October 2003

AbstractThe corn rootworm complex is the most damaging insect pest of corn (Zea mays L.). This study was conducted to determine the efficacy of whorl and pollen‐shed stage applications of a granular formulation of Beauveria bassiana (Balsamo) Vuillemin for control of adult western corn rootworm (Diabrotica virgifera virgifera Le Conte). The effect of application time (whorl‐stage, pollen‐shed) and plant surface exposed (leaves and leaf collars; silks; leaves, leaf collars, and silks) on level of beetle fungal infection were investigated. In addition, the number of colony forming units of B. bassiana in the corn leaf collar area was quantified. In the three years (1998–2000) of the study, application of B. bassiana at whorl‐stage did not significantly increase beetle fungal infection. Beauveria bassiana applied to plants at pollen‐shed in 1998 resulted in a significant increase in beetle infection with 51% of beetles from treated plants infected and 6.0% from control plants. Similar applications at pollen‐shed in 1999 and 2000 resulted in very low infection levels. Beauveria bassiana application at pollen‐shed stage significantly increased the number of colony forming units per leaf collar during all years of the study. Beetle infection with B. bassiana did not differ consistently among plant surface to which beetles were exposed for either application. Increased fungal load in leaf collars was not correlated with increased levels of adult infection. Increased rates of B. bassiana and application when beetles are present on the plants are likely needed to significantly increase infection rates.
Prior encounters modulate subsequent choices in host acceptance behavior by the bark beetle Ips pini
Authors: Wallin Kimberly F. , Raffa Kenneth F. 
Published: October 2003

AbstractLaboratory bioassays indicate that the bark beetle Ips pini employs flexible, rather than absolute, responses to phytochemicals in its host acceptance behavior. Each beetle's decision to enter substrate was influenced by the types and concentrations of monoterpenes present. However, previous rejection of a simulated host containing a moderate concentration of monoterpenes increased the likelihood that the same concentration would be accepted upon a second or third encounter. This flexibility more than offsets any loss of vigor due to starvation and age that accompanies a process of trial and error. Starvation decreased beetles' total lipid content, but beetles can recover some energetic losses by a small amount of feeding during each trial. In addition to its adaptive value, a flexible host acceptance strategy may yield population level consequences. That is, bark beetles preferentially enter trees having low concentrations of monoterpenes, but may modify their acceptance thresholds when cues associated with stressed trees are not available. This could partially explain how some tree‐killing bark beetles colonize a broader physiological range of trees during outbreaks. The adaptive value of relating individual decisions to population density may arise from two ecological relationships: first, as populations rise, the pool of stressed trees is rapidly depleted; secondly, healthy trees are attainable through pheromone – mediated mass attacks when adequate numbers of beetles are present. Flexible host acceptance behaviors may also reduce the advantage of relying exclusively on pre‐landing cues to distinguish between susceptible and non‐susceptible trees.
Effects of age, sex, and dietary history on response to cucurbitacin in Acalymma vittatum
Authors: Smyth Rebecca R. , Tallamy Douglas W. , Renwick J. Alan A. , Hoffmann Michael P. 
Published: October 2003

AbstractThe chrysomelid Acalymma vittatum is stenophagous, subsisting almost entirely on plants in the Cucurbitaceae, which generally contain cucurbitacins. Cucurbitacins are extremely bitter tetracyclic triterpenoids that are toxic to most organisms. As do other diabroticite beetles, A. vittatum sequester cucurbitacins, which have been shown to act as phagostimulants and arrestants. Our results reveal, however, that for A. vittatum the response to cucurbitacin diminishes with continued sequestration. Colony‐reared A. vittatum were fed only roots (as larvae) and foliage of either ‘Marketmore 76’ (which contains a normal amount of cucurbitacin, ‘bitter’) or ‘Marketmore 80’ (a near isogenic line that contains no cucurbitacin, ‘non‐bitter’) cucumber. Over 1200 individual beetles from the day of adult emergence to 15 days following emergence were placed in choice and no‐choice arenas containing potted cotyledons of the two cucumber varieties for 24 h. In choice tests, overall preference for the bitter cucumber cultivar was maintained, but degree of preference changed with age and became significantly less for beetles reared on bitter diets. Furthermore, in no‐choice tests, age, sex, dietary history, and interactions among these variables all significantly affected the feeding response to cucurbitacin. For A. vittatum reared without cucurbitacin, total consumption of the bitter cultivar increased over time. For beetles reared with cucurbitacin, total foliage consumption of the bitter cultivar declined, within nine days, to equal that of the non‐bitter cultivar. Feral A. vittatum, unexpectedly, consumed more of the non‐bitter than the bitter cultivar in no‐choice tests. Ecological and applied implications of this variation in response to cucurbitacin are discussed.
Interactive effects of leaf maturation and phenolics on consumption and growth of a geometrid moth
Authors: Haukioja Erkki , Ossipov Vladimir , Lempa Kyösti 
Published: October 2003

AbstractPhenolic compounds are commonly regarded as the main chemical defenses of deciduous woody plants against insects. To examine how indices of leaf maturation (water content, toughness, and sugar/protein ratio) modified larval consumption and growth relative to phenolics and phenolic‐related leaf traits, we measured consumption and growth of fourth‐instar Epirrita autumnata (Bkh.) (Lepidoptera: Geometridae) larvae on three different days on young, normal, and mature leaves, respectively, from the same mountain birch (Betula pubescens ssp. czerepanovii (Orlova) Hämet‐Ahti) trees. The larvae achieved the same growth rates on young and normal leaves, but had to consume 40% more on the latter. On more mature leaves, larval growth was poorer and was positively correlated with sugar/protein ratios (although the ratio peaked at that time). Indices of leaf maturation correlated with several phenolics in data pooled over the three study days, but poorly in any individual day. Similarly, in the pooled data, larval consumption and growth correlated with several leaf traits, but correlations between leaf and insect traits were few on any of the three days, and no trait was significant on each of the three days.We next examined whether variation in the maturation indices modified the associations of phenolics with insect consumption and growth. When interactions between phenolics and leaf maturation indices were taken into account, the number of phenolic compounds displaying significant associations with insect traits more than doubled. The relative importance of interactive versus direct associations increased with leaf maturation: on young leaves five phenolics showed direct and eleven interactive associations with insect traits, while in mature leaves we found two phenolics to display direct and thirteen phenolics interactive associations. Leaf water content, either alone or together with toughness and sugar/protein ratio, generally explained more of the variance in Epirrita growth (up to 59%) than any phenolic or phenolic‐related trait alone (highest value 20%). Including interactive effects between phenolics and indices of leaf maturation in the model increased the proportion explained of variance in larval growth between 49 and 73%. Maturation indices explained 0 to 23% of variance in consumption, and the phenolic compound with the highest (positive!) correlation alone up to 28%, but taking into account interactions between phenolics and maturation indices raised the degree of explanation much (namely, 32 to 53%) over that explained by indices of leaf maturation alone. This indicates strong interactive effects on consumption between phenolics and indices of leaf maturation.
The effect of ozone fumigation and different Brassica rapa lines on the feeding behaviour of Pieris brassicae larvae
Authors: Jøndrup Pernille M. , Barnes Jeremy D. , Port Gordon R. 
Published: October 2003

AbstractElevated levels of tropospheric ozone and their effects on plants have been studied for a great number of years. Ozone is a gaseous pollutant and acts as a phytotoxin. Even though ozone is known to change the physiology of plants, little attention has been given to the indirect effects of ozone on plant‐insect interactions. This paper addresses this question by investigating the interactive effects of ozone and plant genotype on insects. Lines of rapid‐cycling Brassica rapa (L.) selected for their contrasting sensitivity to ozone and Pieris brassicae (L.) (Lepidoptera: Pieridae) were used as a model system. The effect of differences in ozone sensitivity and ozone fumigation on the plant's carbon and nitrogen pools, the feeding preference, and behaviour of P. brassicae larvae were investigated. The results show that the plant's susceptibility to ozone interacts in a complex way with ozone induced alterations in the suitability of the plant for the insect. Only the larval performance on the sensitive line was affected by ozone exposure. Biochemical changes in the resistant B. rapa line made the plant a better food source for the insects, since the digestibility of this plant was significantly higher than that of the sensitive line, and the larvae pupated more quickly and were heavier.