bluuebunny/crossref_metadata_2025 huggingface dataset:
Acetazolamide Acts on Neuromuscular Transmission Abnormalities Found in Some Migraineurs
Authors: Ambrosini A , Pierelli F , Schoenen J
Published: December 2004

Mild subclinical impairment of neuromuscular transmission can be detected with single-fibre electromyography (SFEMG) in subgroups of patients suffering from migraine and could be due to dysfunctioning Ca2+-channels on motor axons controlling stimulation-induced acetylcholine release. Acetazolamide, which is thought to ameliorate ion channel function, was shown effective in familial hemiplegic migraine and episodic ataxia type 2, both of which are associated with mutations of the neuronal Ca2+-channel gene CACNA1A, as well as in aura status. We treated therefore in an open pilot study five non-hemiplegic migraineurs showing mild SFEMG abnormalities with acetazolamide for several weeks. This was followed by a normalization of SFEMG recordings in all patients and by clinical improvement in four. These results support the assumption that the subclinical impairment of neuromuscular transmission found in certain migraineurs might be due to dysfunctioning Ca2+-channels.
Reversible Segmental Cerebral Vasoconstriction (Call-Fleming Syndrome): Are Calcium Channel Inhibitors A Potential Treatment Option?
Authors: Nowak DA , Rodiek SO , Henneken S , Zinner J , Schreiner R , Fuchs H-H , Topka H
Published: December 2004

The Call-Fleming syndrome is characterized by sudden onset of thunderclap-like headache and focal neurological deficits. The pathophysiological correlate is a reversible segmental cerebral vasoconstriction frequently associated with focal cerebral ischaemia. The syndrome has been described in a variety of clinical conditions, and recently an association between the syndrome and exposure to vasoactive drugs was observed. Effective treatment options are not known. A 63-year-old female developed sudden ‘worst ever’ headache. Initial neurological examination, laboratory blood tests, CSF examination and brain magnetic resonance imaging (MRI) were normal. Previous medical history was unremarkable and she did not take vasoactive drugs. Eleven days after the onset of headache she developed visual field impairment and a right-sided hemiparesis. Brain MRI revealed bilateral posterior and left parietal ischaemic strokes. Cerebral catheter angiography showed segmental arterial vasoconstriction. A vasodilatative therapy with calcium channel inhibitors was started and serial transcranial Doppler ultrasonography demonstrated resolution of cerebral arterial vasoconstriction. The present case illustrates that calcium channel inhibitors may be an effective therapy for segmental cerebral arterial vasoconstriction. However, more clinical data are needed to prove this observation.
One-Year Prevalence of Migraine in Austria: A Nation-Wide Survey
Authors: Lampl C , Buzath A , Baumhackl U , Klingler D
Published: December 2004

This study presents the first nation-wide survey of migraine in Austria. A sample of 997 Austrian ≥ 15 years old were interviewed personally (face-to-face) in a random sample in the whole country. Diagnosis of migraine was based on the International Headache Society (IHS) classification. Of the Austrian adult population 10.2% were identified to suffer from IHS migraine, 5.6% from migraine without aura, 2.3% from migraine with aura and 2.3% from borderline migraine. Another 8.5% have possible migraine. Other primary headaches were reported in 30.7%. Sex, age, working status and region were found to be the main demographic influencing factors. Further influences were stress, spinal column problems or weather changes. The most used acute medications were over-the-counter drugs, doctor attendance rate was very low. Working people with migraine dropped out of work 14 days per year, which adds up to 6.8 million working days per year. This remains a substantial economic factor. The findings indicate that migraine sufferers in Austria need to be more informed about their illness and what to do against it, especially encouraging doctor visits.
Peripheral and Central Mechanisms in Tension-Type Headache: an Update
Authors: Jensen R
Published: December 2004

Despite the tremendous socoeconomic impact of tension-type headache surprisingly little is known about the underlying pathophysiology and treatment. Existing evidence and theories about the relation between central and peripheral mechanisms are discussed. Central sensitization is probably the most important key to understand this widespread disorder. An effective prevention or reversal of this central sensitization will probably be of major importance in future treatment strategies.
Syncope – an unusual presentation of ventricle dysfunction in a patient with Fontan circulation
Authors: Holmgren Daniel , Redfors Staffan , Rydberg Annika , Wåhlander Håkan
Published: December 2004

We report a case of recurrent syncope in association with moderate ventricular dysfunction and mild AV‐valve regurgitation in an 18‐year‐old girl, 4 years after she underwent total cavopulmonary connection surgery. Cardiac catheterization revealed a transpulmonary gradient of 1–2 mmHg. During exercise, a dramatic fall in blood pressure and blood oxygenation was observed, paralleled by an increase in heart rate and central venous pressure. Although a slight increase in pulmonary vascular resistance could not be excluded, the reaction was interpreted in terms of an extremely low transpulmonary gradient in association with ventricular dysfunction. Five months after heart transplantation, the patient has been completely free from syncope. Fontan circulation usually involves a delicate haemodynamic situation which may necessitate haemodynamic re‐evaluations, including dynamic measurements of the central venous pressure during exercise. Also a moderate ventricular dysfunction may result in compromised pulmonary circulation which in turn may lead to syncope during exercise as a result of insufficient systemic circulation.
Relationship between breath‐synchronous arterial pressure and heart rate variations during orthostatic stress
Authors: Sundblad Patrik , Linnarsson Dag
Published: December 2004

It has recently been shown that the phase relationship between respiration‐induced changes in arterial pressure (AP) and heart rate (HR) are different in supine and upright postures. We wanted to further analyse the coupling between respiration, arterial blood pressure and HR in the time domain, and how this coupling was altered during orthostatic stress. Nine healthy subjects were studied. Respiration‐induced changes in AP and HR were recorded during frequency‐ and volume‐controlled breathing. This was done during supine rest with and without lower body negative pressure (−50 mmHg) (LBNP). All experiments were performed after β1‐blockade. Responses were averaged breath‐by‐breath to enhance the time resolution and to eliminate noise. The respiration‐induced changes in arterial pulse pressure (PP) were different between control and LBNP: The peak in PP during the respiratory cycle occurred 0·9 ± 0·8 (mean ± SD) s before the onset of inspiration during supine control and 0·8 ± 2·1 s after the onset of inspiration during LBNP (P = 0·03). These changes in the timing of peak PP significantly distorted the cyclic systolic AP and mean AP fluctuations during LBNP. Despite the altered AP response with LBNP, HR fluctuations closely correlated in time with respiration in all conditions, albeit with a significantly reduced amplitude during LBNP (−49%, P = 0·01). The results points to a lack of coupling between AP and HR during paced breathing and thus suggest that respiratory sinus dysrhythmia at least, to a large extent, is independent of the arterial baroreflex.
Human SP‐A and a pharmacy‐grade porcine lung surfactant extract can be reconstituted into tubular myelin – a comparative structural study of alveolar surfactants using cryo‐transmission electron microscopy
Authors: Larsson Marcus , van Iwaarden J. Freek , Haitsma Jack J. , Lachmann Burkhard , Wollmer Per
Published: December 2004

Cryo‐transmission electron microscopy (cryo‐TEM) is a rather artefact‐free method, well suited to study the alveolar surfactant system. A pharmacy grade porcine lung surfactant extract (HL‐10) was mixed with human SP‐A and Ringer's solution (for calcium ions), and it was shown by cryo‐TEM that the tubular myelin (TM) type of structure was reconstituted. These aggregates were associated to liposomal aggregates, and resulted in macroscopic phase‐separation. This phase showed a weak birefringence in the polarising microscope, which is characteristic for a liquid‐crystalline type of structure. TM from rabbit lung lavage was also examined, and showed the same periodic arrangement of bilayers as alveolar surface layer from freshly cut rabbit lungs deposited directly on the cryo‐TEM grids. The distance between the bilayers of TM was 40–50 nm, and an electron dense material, assumed to be SP‐A, was sometimes seen to occur periodically along the bilayers, oriented perpendicularly to the tubuli. The results are consistent with the surface‐phase model of the alveolar lining.
EMG signs of neuromuscular fatigue related to the ventilatory threshold during cycling exercise
Authors: Hug François , Faucher Marion , Kipson Nathalie , Jammes Yves
Published: December 2004

SummaryWe questioned whether electromyographic (EMG) signs of neuromuscular fatigue accompany the changes in respiratory variables measured at the ventilatory threshold (VTh) during exercise on a cycloergometer. This was based on the assumption that the activation of muscle afferents sensitive to accumulation of lactate and potassium is suspected to elicit both the EMG signs of fatigue and hyperventilation. In 39 subjects performing an incremental cycling, the EMG estimates of neuromuscular fatigue in vastus lateralis were a non‐linear increase in root mean square (RMS), a decrease in median frequency (MF), a non‐linear increase in low‐frequency EMG energies (EL), and/or a decrease in high‐frequency energies (EH).VThwas determined from a non‐linear increase inVCO2[VTh(VCO2slope)] and an increased value of the respiratory equivalent for oxygen [VTh(VE/VO2)]. We measured a significant increase in venous blood concentration of lactate and potassium, and a significant pHv fall atVTh. One EMG estimate of fatigue was detected in 33/39 individuals and two EMG estimates in 17 subjects. Highly significant positive correlations were found between the oxygen uptakes corresponding to each EMG estimate and to each detection criterion ofVTh. These observations suggest that the activation of muscle sensory pathways contribute to the mechanism ofVTh.
Expression of one sponge Iroquois homeobox gene in primmorphs from Suberites domuncula during canal formation
Authors: Perović Sanja , Schröder Heinz C. , Sudek Sebastian , Grebenjuk Vladislav A. , Batel Renato , ˇStifanić Mauro , Müller Isabel M. , Müller Werner E. G.
Published: December 2004

SUMMARY Sponges (Porifera) represent the evolutionary oldest multicellular animals. They are provided with the basic molecules involved in cell–cell and cell–matrix interactions. We report here the isolation and characterization of a complementary DNA from the sponge Suberites domuncula coding for the sponge homeobox gene, SUBDOIRX‐a. The deduced polypeptide with a predicted Mr of 44,375 possesses the highly conserved Iroquois‐homeodomain. We applied in situ hybridization to localize Iroquois in the sponge. The expression of this gene is highest in cells adjacent to the canals of the sponge in the medulla region. To study the expression of Iroquois during development, the in vitro primmorph system from S. domuncula was used. During the formation of these three‐dimensional aggregates composed of proliferating cells, the expression of Iroquois depends on ferric iron and water current. An increased expression in response to water current is paralleled with the formation of canal‐like pores in the primmorphs. It is suggested that Iroquois expression is involved in the formation of the aquiferous system, the canals in sponges and the canal‐like structures in primmorphs.
Heat shock in the developmentally sensitive period of butterfly eyespots fails to increase fluctuating asymmetry
Authors: Breuker Casper J. , Brakefield Paul M.
Published: December 2004

SUMMARYFluctuating asymmetry (FA) is considered to provide a means of evaluating developmental stability and to reflect an individual's quality or the stress experienced during development. Stress is predicted to increase the phenotypic variation of both FA and trait size. In this study we examined the effect of a particular heat shock on both FA and size of eyespots in the butterfly,Bicyclus anynana.We also examined whether those eyespots thought to be involved in partner choice and sexual selection were particularly sensitive to stress. We applied a heat shock of 39.5°C for 3 h before, during, and after a sensitive period in eyespot development. We examined the FA, variation in FA, size, and variation in size of five eyespots, two on the dorsal forewing (sexually selected traits), two on the ventral forewing, and one on the ventral hindwing (nonsexually selected traits). For each sex and treatment, the heat shock did not result in significant changes in mean trait size and FA nor in the variation of size and FA. There were no differences in the response to the heat shock between sexually and nonsexually selected traits. We discuss how the increased production of heat shock proteins, including HSP60, may have stabilized development and how this might explain the results.
A mechanistic study of evolvability using the mitogen‐activated protein kinase cascade
Authors: Nijhout H. F. , Berg A. M. , Gibson W. T.
Published: December 2004

SUMMARY Evolvability is a function of the way genetic variation interacts with the mechanisms that produce the phenotype. We explore an explicitly mechanistic way of studying the evolvability of phenotypes that are produced by a relatively simple genetic mechanism, the mitogen‐activated protein kinase (MAPK) cascade. We developed a quantitative model of MAPK activation that can be used to study the effects of genetic variation on the various components of this signaling cascade. We show how some standard tools of applied mathematics, such as steady‐state formulations and nondimensionalization, can be used to elucidate the relative importance of variation in each gene of this mechanism. We also give insights into non‐intuitive patterns of dependence and trade‐off among the genes. The mechanism produces several different phenotypes (ultrasensitivity to stimulation, switch‐like behavior, amount of MAPK‐PP delivered, persistence of MAPK‐PP activity), each of which is sensitive to different (but partially overlapping) combinations of genes. We show that the mechanism imposes clear limitations on the evolvability of each of the different phenotypes of the pathway, even in the presence of genetic variation in the components of the mechanism. This approach to the study of evolvability is generally applicable and complements the traditional approach through statistical genetics by providing a mechanistic understanding of the genetic interactions that produce the phenotype.
Conflicting phylogenetic signals at the base of the metazoan tree
Authors: Rokas Antonis , King Nicole , Finnerty John , Carroll Sean B.
Published: December 2004

SummaryA phylogenetic framework is essential for under‐standing the origin and evolution of metazoan development. Despite a number of recent molecular studies and a rich fossil record of sponges and cnidarians, the evolutionary relationships of the early branching metazoan groups to each other and to a putative outgroup, the choanoflagellates, remain uncertain. This situation may be the result of the limited amount of phylogenetic information found in single genes and the small number of relevant taxa surveyed. To alleviate the effect of these analytical factors in the phylogenetic recons‐truction of early branching metazoan lineages, we cloned multiple protein‐coding genes from two choanoflagellates and diverse sponges, cnidarians, and a ctenophore. Comparisons of sequences for α‐tubulin, β‐tubulin, elongation factor 2, HSP90, and HSP70 robustly support the hypothesis that choanoflagellates are closely affiliated with animals. However, analyses of single and concatenated amino acid sequences fail to resolve the relationships either between early branching metazoan groups or between Metazoa and choano‐flagellates. We demonstrate that variable rates of evolution among lineages, sensitivity of the analyses to taxon selection, and conflicts in the phylogenetic signal contained in different amino acid sequences obscure the phylogenetic associations among the early branching Metazoa. These factors raise concerns about the ability to resolve the phylogenetic history of animals with molecular sequences. A consensus view of animal evolution may require investigations of genome‐scale characters.
Defining phyla: morphological and molecular clues to metazoan evolution
Authors: Nielsen Claus
Published: December 2004

Summary None of the supraspecific taxonomic categories can be defined objectively. Each taxon should of course be monophyletic, but there is no morphological or molecular character that identifies, for example, the phylum level. This has led some authors to abandon the Linnaean categories, but they appear to be practical “handles” in daily communication. It has been proposed that each phylum exhibits a characteristic Bauplan, but the identification of such “types” have in practice proved difficult or impossible for several phyla. Monophyly of some of the approximately 30 morphology‐based phyla has been put in question by molecular studies, but recent reports clearly show that the 18S rRNA molecule, which has been used extensively in phylogenetic analyses, cannot be used alone in identifying phyla (or other higher taxonomic groups). Some higher taxa, for example Chordata, Vertebrata, and Echinodermata, consistently show up as monophyletic in the analyses, whereas molluscan and annelidan subgroups just as consistently are mixed with each other and with a number of other protostomian phyla in varying patterns.
Neuropsychology of Epilepsy
Authors: Matsuoka Hiroo
Published: December 2004

Summary:  Purpose: The neuropsychological approach to epilepsy is indispensable for assessment of cognitive function in an interictal period including pre‐ and postsurgical evaluation, and for disclosing the semiology of nonconvulsive status epilepticus. Another use of the neuropsychological approach is to identify a seizure‐precipitating factor by loading systematic cognitive tasking, termed “neuropsychological EEG activation” (NPA), during standard EEG recordings.

Methods: In this study, NPA tasks consisted of reading, speaking, writing, written arithmetic calculation, mental arithmetic calculation, and spatial construction.

Results: The NPA tasks provoked epileptic discharges in 7.9% of the 480 epileptic patients and were often accompanied by myoclonic seizures. Among the cognitive tasks, mental activities mainly associated with use of the hands [i.e., writing (68.4%), written calculation (55.3%), and spatial construction (63.2%)] provoked the most discharges. Seizure‐precipitating mental activities were found to be almost exclusively related to idiopathic generalized epilepsies (IGEs).

Conclusions: These results suggest that NPA is a useful tool for examining the relationship between cognitive function and epileptic seizures, and that the IGE patients with myoclonic seizures are vulnerable to higher mental activity.
Elderly Patients with Systemic Disease
Authors: Boggs Jane G.
Published: December 2004

Although the healthy elderly seizure patient can often be treated with antiepileptic drugs (AEDs) similarly to a younger counterpart, the elderly with systemic disease require a more complex approach. The interplay of multiple organ dysfunctions and multiple non‐AED medications greatly increases the challenges of managing the majority of older epilepsy patients. In addition, age‐related physiologic changes in hepatic and renal function, volume of distribution, and exaggerated sensitivity to side effects alter the usual “rules” for administering AEDs. Thorough knowledge of the general principles of geriatric physiology and pharmacology may predict optimal selection of initial or subsequent AED therapy in this population.
Usefulness of Transesophageal Three‐Dimensional Echocardiography in the Identification of Individual Segment/Scallop Prolapse of the Mitral Valve
Authors: Ahmed Sujood , Nanda Navin C. , Miller Andrew P. , Nekkanti Rajasekhar , Yousif Abdalla M. , Pacifico Albert D. , Kirklin James K. , McGiffin David C.
Published: December 2004

We evaluated the potential usefulness of three‐dimensional (3D) transesophageal echocardiography (TEE) in assessing individual scallop/segment prolapse in 36 adult patients with mitral valve prolapse (MVP) undergoing surgical correction. Intraoperative 3D TEE correctly identified the location of scallop/segment prolapse in 34 of 36 patients (94%). However, in 6 of these patients 3D TEE images revealed more scallops or segments with prolapse than the surgeon noted intraoperatively. Prolapse of these areas was less prominent and this could possibly explain the lack of correlation with the surgical findings in these patients. In another 2 patients areas of prolapse seen by the surgeon were missed by 3D TEE because some of those scallops/segments could not be well imaged due to image “drop out” and artifacts. Thus, perfect correlation between 3D TEE and surgery was noted in 28 of 36 (78%) patients. Noncoaptation of the MV was also identified in 2 patients. The prolapsed area of posterior (n = 28 observations) and anterior (n = 9 observations) MV leaflets ranged from 1 cm2 to 9 cm2 (mean 3.50 cm2± 2.14) and 1.20 cm2 to 5.99 cm2 (mean 3.21 cm2± 1.33), respectively. Interobserver and intraobserver agreement for location and area of MVP was excellent (r = 0.97 and r = 0.99, respectively; all P values are <0.0001). In conclusion, 3D TEE is useful in identifying the location of MVP. It may also be potentially useful in assessing the extent of individual scallop/segment prolapse and identifying sites of MV noncoaptation. This information could aid the surgeon in deciding the extent of MV resection. (ECHOCARDIOGRAPHY, Volume 20, February 2003)
Ankylosing Spondylitis in Association With Mitral Stenosis, Mitral Regurgitation, and Aortic Regurgitation: A Case Report and Review of the Literature
Authors: Gupta B. K. , Panwar Raja Babu , Kabra P. K. , Kaushik A. N. , Meena G. L. , Chadda V. S.
Published: December 2004

We report on a patient with ankylosing spondylitis in association with mitral stenosis, mitral regurgitation, and aortic regurgitation. Despite extensive search of literature, we could not find association of mitral stenosis with ankylosing spondylitis. This report is the first to describe this association. Our findings are based on clinical and echocardiographic findings. (ECHOCARDIOGRAPHY, Volume 20, April 2003)
Successful Repair of Aortic and Mitral Incompetence Induced by Methylsergide Maleate: Confirmation by Intraoperative Transesophageal Echocardiography
Authors: Joseph Thomas , Tam Stanley K.C. , Kamat Brinda R. , Mangion Judy R.
Published: December 2004

Methylsergide maleate, an effective anti‐migraine medication, has a well‐documented association with left‐sided cardiac valve dysfunction. Prior reports have described cardiac valve dysfunction in patients using methylsergide chronically for a minimum of 6 years, with surgical intervention consisting of valve replacement for patients with intractable congestive heart failure. We report a 51‐year‐old woman who developed severe mitral and aortic valvular dysfunction after taking methylsergide maleate for migraine headaches for a period of 19 months, and who subsequently underwent aortic and mitral valve repair with excellent short‐term results. (ECHOCARDIOGRAPHY, Volume 20, April 2003)
Role of volatiles emitted by host and non‐host plants in the foraging behaviour of Dentichasmias busseolae, a pupal parasitoid of the spotted stemborer Chilo partellus
Authors: Gohole Linnet S. , Overholt William A. , Khan Zeyaur R. , Vet Louise E. M.
Published: December 2004

The role of volatiles from stemborer host and non‐host plants in the host‐finding process of Dentichasmias busseolae Heinrich (Hymenoptera: Ichneumonidae) a pupal parasitoid of Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) was studied. The non‐host plant, molasses grass (Melinis minutiflora Beauv. (Poaceae)), is reported to produce some volatile compounds known to be attractive to some parasitoid species. The studies were conducted to explore the possibility of intercropping stemborer host plants with molasses grass in order to enhance the foraging activity of D. busseolae in such a diversified agro‐ecosystem. Olfactometric bioassays showed that volatiles from the host plants maize, Zea mays L., and sorghum, Sorghum bicolor (L.) (Poaceae), were attractive to the parasitoid. Infested host plants were the most attractive. Volatiles from molasses grass were repellent to the parasitoid. Further tests showed that volatiles from infested and uninfested host plants alone were preferred over those from infested and uninfested host plants combined with the non‐host plant, molasses grass. In dual choice tests, the parasitoid did not discriminate between volatiles from maize infested by either of the two herbivore species, C. partellus or Busseola fusca Fuller (Lepidoptera: Noctuidae). Volatiles from sorghum infested by C. partellus were preferred over those from C. partellus‐infested maize. The study showed that the pupal parasitoid D. busseolae uses plant volatiles during foraging, with those from the plant–herbivore complex being the most attractive. The fact that volatiles from molasses grass were deterrent to the parasitoid suggested that intercropping maize or sorghum with molasses grass was not likely to enhance the foraging behaviour of D. busseolae. Volatiles from the molasses grass may hinder D. busseolae's host location efficiency.
Identification of a coffee berry borer‐associated yeast: does it break down caffeine?
Authors: Vega Fernando E. , Blackburn Michael B. , Kurtzman Cletus P. , Dowd Patrick F.
Published: December 2004

Two yeasts isolated from laboratory reared adult coffee berry borers [Hypothenemus hampei (Ferrari) (Coleoptera: Scolytidae)] and from insects collected in the field in Colombia were identified as Pichia burtonii Boidin and Candida fermentati (Saito) Bai, based on sequencing of the nuclear large subunit 26S rDNA variable D1/D2 domain. Liquid culture experiments using P. burtonii in media containing different caffeine levels indicated that caffeine levels in a range found within coffee seeds can retard yeast growth. HPLC analysis shows that P. burtonii does not break down caffeine.
Soil nutrients and water availability interact to influence willow growth and chemistry but not leaf beetle performance
Authors: Lower Steven S. , Orians Colin M.
Published: December 2004

We investigated the effects of soil nutrient and water availability on the growth and chemistry of the silky willow (Salix sericea Marshall), and on the performance of the imported willow leaf beetle (Plagiodera versicolora Laichartig). Our major aims were to determine whether there are nutrient–water interactions on plant traits and whether this leads to parallel interactions for herbivore performance. We used a 2 × 3 fully factorial design, which consisted of high and low nutrient treatments crossed with dry, field capacity, and flooded water treatments. We found that nutrient additions increased plant growth, but only in field capacity and flooded conditions (nutrient–water interaction). Leaf nitrogen content also depended on the interaction between soil nutrients and water: nutrient addition resulted in a larger increase in foliar nitrogen in the field capacity treatment than in the flooded and dry treatments. Of the two phenolic glycosides measured, salicortin and 2′‐cinnamoylsalicortin, only one was affected by the treatments. 2′‐cinnamoylsalicortin concentration was lower in the high nutrient–dry treatment compared with the other treatments. In contrast to plant responses, there were no interactions found for larval or pupal weight or development time. Nutrient addition led to an increase in female pupal weight, and foliar N was positively correlated with female pupal weight and negatively correlated with female development time. In addition, leaf water was positively correlated with female development time. The lack of interactions for insect performance may stem from the small absolute differences in foliar nitrogen content associated with the interaction between the nutrients and water. Taken together, our results suggest that nutrient–water interactions influence plant traits that are potentially important for insect performance (leaf nitrogen and water), but these interactions do not produce parallel interactions in beetle performance.
Endophyte infection in perennial ryegrass reduces the susceptibility of black cutworm to an entomopathogenic nematode
Authors: Kunkel Brian A. , Grewal Parwinder S.
Published: December 2004

Abstract The perennial ryegrass, Lolium perenne, forms a symbiotic relationship with Neotyphodium lolii, a fungus that produces alkaloids. This relationship provides a competitive advantage to the host plant in grassland communities by increasing drought tolerance, and disease and herbivore resistance. Black cutworm, Agrotis ipsilon, is among the few insect species that are able to feed and develop on endophytic perennial ryegrass. Some insects can use plant secondary compounds to defend themselves against predators, therefore we hypothesized that the cutworms fed on endophytic grasses would exhibit greater defense against a lethal endoparasitic nematode, Steinernema carpocapsae. Laboratory experiments involving 4–5th instars support the hypothesis that A. ipsilon feeding on grass clippings from field plots with high (> 90%) incidence of endophyte infected perennial ryegrass are less susceptible to entomopathogenic nematodes than larvae fed grass clippings from plants with little or no incidence of endophyte. Laboratory studies resulted in similar overall mortality after 48 h. Field studies, however, show decreased susceptibility to S. carpocapsae when larvae were confined to areas of endophytic grass (> 75% infected). Early instars (2–3rd) fed on endophyte free grass suffered greater overall mortality at all nematode concentrations than 4–5th instars fed similarly. Early (2–3rd) instars were equally susceptible to nematode attack regardless of food source. Our results indicate that the fungal endosymbionts of grasses can influence the biology of natural enemies of an herbivorous insect.
Side‐effects of cowpea treatment with botanical insecticides on two parasitoids of Callosobruchus maculatus
Authors: Boeke Sara J. , Sinzogan Antonio A.C. , De Almeida Raul P. , De Boer Paul W.M. , Jeong Gilsang , Kossou Dansou K. , Van Loon Joop J.A.
Published: December 2004

Studies on the protective effect of botanical products against pest insects have infrequently been extended to side‐effects on natural enemies. Indirect effects of botanicals on the storability of seeds could occur through their possible negative impact on biological control agents. Four plant powders and six plant oils with a known effect on the cowpea beetle Callosobruchus maculatus (Fabr.) (Coleoptera: Bruchidae) were investigated for their effect on the beetles’ egg parasitoid Uscana lariophaga (Steffan) (Hymenoptera: Trichogrammatidae) and the larval parasitoid Dinarmus basalis (Rondani) (Hymenoptera: Pteromalidae). All treatments caused a decrease in parasitisation by U. lariophaga, and developing parasitoids of this species were affected by powders of Nicotiana tabacum (L.) and Tephrosia vogelii (Hook. f). In a two‐choice situation using a linear olfactometer, U. lariophaga was repelled by most of the oils. In a no‐choice situation, parasitisation by D. basalis was hampered by treatment with plant powders, but eggs that were laid developed normally. In a Y‐tube olfactometer, this parasitoid did not discriminate between odours of untreated and plant‐powder‐treated beans. The powders of N. tabacum and T. vogelii had stronger negative effects on the two parasitoids than the powders of Azadirachta indica (Juss.) or Blumea aurita (DC). In samples collected from untreated traditional storage facilities, subsequently treated with plant powders in the laboratory, none of the treatments could prevent the increase in beetle numbers. At 24 days after treatment, most beetles had emerged from beans treated with powders of N. tabacum and T. vogelii. Parasitoids were affected by the botanical insecticides tested here, but the powders of A. indica and B. aurita may be compatible with biological control by D. basalis.
CLINICAL MANAGEMENT OF THE AVULSED TOOTH: PRESENT STRATEGIES and FUTURE DIRECTIONS
Authors: Trope Martin
Published: December 2004

Abstract  – The aim of this review article is to supplement the recently published International Association of Dental Traumatology (IADT) guidelines on treatment of the avulsed tooth. A thorough discussion on the reasoning behind each guideline is presented. In addition, the author's views on alternate treatment strategies and future directions, along with recent research on the subject of the avulsed tooth, are also presented.
Xeroderma Pigmentosum: Mondscheinkinder
Authors: Herouy Yared , Krutmann Jean , Norgauer Johannes , Schöpf Erwin
Published: December 2004

Das Krankheitsbild des Xeroderma Pigmentosum beruht auf einem Gendefekt im DNS‐Reparatursystem und manifestiert sich bereits in der frühen Kindheit. Beim Xeroderma Pigmentosum handelt es sich um eine seltene autosomal rezessive Genodermatose. Klinisch zeigen diese Kinder eine starke Sonnenempfindlichkeit. Patienten mit Xeroderma Pigmentosum entwickeln schwere Sonnenbrände mit der Ausbildung einer Poikilodermie in lichtexponierter Haut. Bereits in der Kindheit entwickeln sich spinozelluläre Karzinome, Basaliome und maligne Melanome. Die Mehrzahl der Patienten versterben vor dem Erreichen des Erwachsenenalters aufgrund metastasierender kutaner Malignome. Genetisch wird das Xeroderma Pigmentosum in 7 Komplementationsgruppen (XP‐A bis XP‐G) und die Xeroderma‐Pigmentosum‐Variante (XP‐V) unterteilt. Diagnostisch erfolgt die Zuordnung in die jeweilige Komplementationsgruppe durch Fusionierung von Xeroderma‐Pigmentosum‐Fibroblasten. Differentialdiagnostisch muß das Xeroderma Pigmentosum von anderen sogenannten DNS‐Reparatur‐Defizienz‐Syndromen wie dem Cockayne‐Syndrom und der Trichothiodystrophie abgegrenzt werden. Aktuell wird über eine erfolgreiche Anwendung eines topisch applizierten DNS‐Reparatur‐Enzyms berichtet. Hierbei handelt es sich um eine rekombinante liposomal verkapselte T4‐Endonuklease V, welche UV‐induzierte Cyclobutan‐Pyrimidin‐Dimere repariert. In Zukunft könnte eine kausale Behandlung auf der Gentherapie basieren. Das Einschleusen eines intakten Reparaturgens, welches spezifisch das Reparaturprotein kodiert, könnte neue Möglichkeiten der Behandlung des Xeroderma Pigmentosum eröffnen.
Histologische Diagnose der Onychomykose
Authors: Herbst Rudolf A. , Brinkmeier Thomas , Frosch Peter J.
Published: December 2004

Wegen möglicher Nebenwirkungen und der relativ hohen Kosten einer systemischen antimykotischen Therapie muß dieser eine sichere Diagnosestellung vorangehen. Hierzu sind die lichtmikroskopische „Nativuntersuchung” und die Pilzkultur die am weitesten verbreiteten Methoden. Nach eigenen und den Erfahrungen anderer gibt es immer wieder Patienten, bei denen sich der klinische Verdacht auf eine Onychomykose auch durch wiederholte Nativuntersuchungen und Pilzkulturen nicht erhärten läßt. In diesen Fällen kann die histologische Untersuchung als Zusatzuntersuchung hilfreich sein. Im eigenen Kollektiv von 32 histopathologisch nachgewiesenen Fällen von Onychomykose war in nur 14 von 29 Fällen (48 %) die Pilzkultur positiv. Die Nativuntersuchung wurde nur in 12 Fällen durchgeführt, da meistens mehrfach negative Befunde der zuweisenden Dermatologen vorlagen: sie war in 5 Fällen (42 %) positiv. Neben der Sensitivität – insbesondere in schwierig zu diagnostizierenden Fällen – sind die fehlende Gefahr einer Kontamination, der Erhalt eines dauerhaften Präparates mit der Möglichkeit, die Invasion des Nagelorgans sowie andere bzw. begleitende Nagelerkrankungen zu demonstrieren, die einfache Durchführbarkeit sowie ein schnelles Ergebnis weitere Vorteile der Histologie. Eine Erregerspezifizierung ist durch die Histologie allerdings nicht möglich. Da die histologische Untersuchung in der aktuellen Leitlinie der DDG zur Onychomykose nicht erwähnt wird, möchten wir hiermit an diese einfache, aber dennoch sensitive Zusatzuntersuchungsmethode in der Diagnostik von Nagelpilzerkrankungen erinnern.
Berufliche Beifuß‐Allergie
Authors: Kurzen Marina , Bayerl Christiane , Goerdt Sergij
Published: December 2004

Hintergrund: Beifuß (Artemisia vulgaris) wird traditionell als Gewürz, Gemüse und Heilpflanze eingesetzt. Zur Familie der Artemisiagewächse gehören auch andere bekannte Vertreter wie z. B. Artemisia absinthum und Artemisia dracunculus (Estragon). Beifuß‐Allergene sind bedeutsam für die Pollinose des Spätsommers; bekannt sind auch Kreuzallergien von Beifußpollen mit verschiedenen Nahrungsmitteln aus der Familie der Umbelliferae wie z. B. Sellerie, Karotten und bestimmte Gewürze.

Patienten: In der vorliegenden Arbeit berichten wir über eine Floristin, die bei vorbestehender Allergie auf Sonnenblumen nach beruflichem Kontakt mit Beifuß ein lebensbedrohliches subglottisches Ödem entwickelte. Ein orales Allergiesyndrom auf Beifußpollenkreuzallergene lag nicht vor.

Ergebnisse: Bei der allergologischen Diagnostik fand sich in den Hauttestungen (Prick‐ und Scratchtestung) eine hochgradige Sensibilisierung gegenüber Beifuß und Estragon. Die spezifischen IgE‐Antikörper gegen Beifuß‐, Sonnenblumen‐, Karotten‐, Sellerie‐, Fenchel‐ und Anis‐Antigene im Blut waren erhöht.

Schlußfolgerungen: Die Beobachtung einer ausgeprägten Beifuß‐Allergie bei einer Floristin unterstreicht das allergene Potential von Artemisia‐Gewächsen und zeigt erstmals die berufliche Relevanz einer solchen Allergie.
Kinetic Theory of Moderately Dense Gases
Authors: Snider R. F. , Curtiss C. F.
Published: December 2004

A kinetic theory of moderately dense gases is developed. The theory is based on a modified Boltzmann equation, which takes into account the ``collisional transfer'' of momentum and energy. The theory applies to pure gases made up of spherical molecules, and the effect of multiple collisions is neglected. The Boltzmann equation is solved by a perturbation method which is applicable near equilibrium. Expressions for the flux coefficients, i.e., the thermal conductivity, bulk, and shear viscosity are obtained from this solution and these are in turn evaluated for a rigid sphere potential.
Interaction of Cylindrical Sound Waves with a Stationary Shock Wave
Authors: Johnson W. R. , Laporte Otto
Published: December 2004

The interaction of cylindrical sound waves with a stationary shock is investigated by a method analogous to that used by H. Weyl in his treatment of the propagation of radio waves over the surface of a plane earth. The incident cylindrical sound wave is represented as a superposition of plane sound waves of varying direction. Each of the plane waves in this superposition interacts with the shock giving rise to a previously determined distortion of the shock front and reflected or refracted wave field; the cylindrical wave causes a disturbance which may be written in integral form as a superposition of these plane waves. The resulting interaction integrals are evaluated asymptotically to give explicit formulas for the distortion of the shock, the sound field, and the entropy-vorticity wave.
The Stellarator Concept
Authors: Spitzer Lyman
Published: December 2004

The basic concepts of the controlled thermonuclear program at Project Matterhorn, Princeton University are discussed. In particular, the theory of confinement of a fully ionized gas in the magnetic configuration of the stellarator is given, the theories of heating are outlined, and the bearing of observational results on these theories is described.

Magnetic confinement in the stellarator is based on a strong magnetic field produced by solenoidal coils encircling a toroidal tube. The configuration is characterized by a ``rotational transform,'' such that a single line of magnetic force, followed around the system, intersects a cross-sectional plane in points which successively rotate about the magnetic axis. A theorem by Kruskal is used to prove that each line of force in such a system generates a toroidal surface; ideally the wall is such a surface. A rotational transform may be generated either by a solenoidal field in a twisted, or figure-eight shaped, tube, or by the use of an additional transverse multipolar helical field, with helical symmetry.

Plasma confinement in a stellarator is analyzed from both the macroscopic and the microscopic points of view. The macroscopic equations, derived with certain simplifying assumptions, are used to show the existence of an equilibrium situation, and to discuss the limitations on material pressure in these solutions. The single-particle, or microscopic, picture shows that particles moving along the lines of force remain inside the stellarator tube to the same approximation as do the lines of force. Other particles are presumably confined by the action of the radial electric field that may be anticipated.

Theory predicts and observation confirms that initial breakdown, complete ionization, and heating of a hydrogen or helium gas to about 106 degrees K are possible by means of a current parallel to the magnetic field (ohmic heating). Flow of impurities from the tube walls into the heated gas, during the discharge, may be sharply reduced by use of an ultra-high vacuum system; some improvement is also obtained with a divertor, which diverts the outer shell of magnetic flux away from the discharge. Experiments with ohmic heating verify the presence of a hydromagnetic instability predicted by Kruskal for plasma currents greater than a certain critical value and also indicate the presence of other cooperative phenomena. Heating to very much higher temperatures can be achieved by use of a pulsating magnetic field. Heating at the positive-ion cyclotron resonance frequency has been proposed theoretically and confirmed observationally by Stix. In addition, an appreciable energy input to the positive ions should be possible, in principle, if the pulsation period is near the time between ion-ion collisions or the time required for a positive ion to pass through the heating section (magnetic pumping).
Compressibility and Intermolecular Forces in Gases: Methane
Authors: Schamp H. W. , Mason E. A. , Richardson A. C. B. , Altman A.
Published: December 2004

The compressibility of a sample of very pure methane has been measured with high precision from 0°C to 150°C and over a pressure range of about 20 to 230 atmos. The precision attained is of the order of 1 part in 104. Small but consistent discrepancies exist between the present results and earlier measurements, and it is believed these discrepancies are the result of a small impurity of ethane in the methane used earlier. The virial coefficients of methane are redetermined from the present measurements, and the intermolecular forces of methane are calculated from the second virial coefficient for several forms of force laws. These force laws are then used to calculate the third virial coefficient, the crystal properties at 0°K, and the viscosity for comparison with experiment. All the force laws fit the second virial coefficient very well, but some can be eliminated on the basis of the other properties.
Cylindrical Shock Waves from Exploding Wires
Authors: Bennett F. D.
Published: December 2004

A simple technique has been found for rendering visible the shock wave formed by an exploding wire after the shock has separated from the luminous contact surface. A small, plane mirror is placed just behind the wire so as to be perpendicular to the axis of the optical system. Thus the reflected image of the wire explosion coincides with the disturbance itself when seen through the slit by the camera lens. Rotating mirror pictures taken under these conditions show very clear outlines of the parabolic shock wave as it propagates ahead of the luminous contact surface. The separation of the shock and contact surface is complete by about one μsec. Beyond this time the shock is clearly nonluminous and ordinarily would not be visible. Comparison of shock trajectories with predictions from the similarity solutions for strong shock waves obtained by S. C. Lin may be interpreted as showing that the shock is receiving additional energy while traversing the early part of its path. After this phase both shock and contact surface accurately obey a parabolic law over intervals of several microseconds.
High-Altitude Atmospheric Density
Authors: Sterne Theodore E.
Published: December 2004

Atmospheric density values obtained from the motion of artificial earth satellites, at altitudes between 186 and 656 kilometers, are discussed. There is some doubt about the reliability of densities from satellites because of the effects of ionization and, in the case of nonspherical satellites, because of their orientation. Densities inferred from satellites are higher than for the ARDC model of the atmosphere. These densities are about ten times higher than densities inferred from rocket-borne ionization gauges between 186 and 230 kilometers.

The inference of atmospheric density from rocket-borne ionization gauges is discussed critically, and densities so obtained are considered to be inferior in reliability to the satellite densities. The satellite densities suggest molecular scale temperatures higher than those of the ARDC model in one or more regions of altitude above 80 kilometers.
Interaction of the Solar Wind with the Geomagnetic Field
Authors: Parker E. N.
Published: December 2004

The dynamical properties of the solar wind blowing past the geomagnetic field are investigated by considering the effective viscosity and the resulting transition layer thickness. The collision of ions in the solar wind produces a negligible viscosity in the flow past the geomagnetic field, but such an inviscid flow is shown to be unstable. The resulting disordered interface between the field and the wind yields Fermi acceleration of ions and consequently a not insignificant effective viscosity. The Fermi acceleration results in suprathermal ions which may have an energy spectrum like that observed for primary auroral protons.

The auroral zones and the agitated nature of the polar geomagnetic field are shown to follow from the depth of penetration of the solar wind into the geomagnetic field. The injection of gas into the geomagnetic field is studied. The effect at Earth of the distortion of the outer boundary of the geomagnetic field is computed; no matter how unevenly and anisotropically the outer field is distorted, the effect at Earth is a nearly uniform perturbation field which is closely parallel to the geomagnetic axis. Pushing in on the outer field increases the horizontal component at Earth, and pulling out decreases it; the total increase of the horizontal component is the algebraic sum of all the pushing and pulling. The simultaneous world-wide onset and the main phase of a geomagnetic storm follow.

The common tendency of large and/or violent bodies of plasma to produce suprathermal particles is noted and suggested to be a general dynamical property.