bluuebunny/crossref_metadata_2025 huggingface dataset:
Low vs. high concentration of levobupivacaine for post‐operative epidural analgesia: influence of mode of delivery
Authors: Dernedde M. , Stadler M. , Bardiau F. , Seidel L. , Boogaerts J. G.
Published: April 2006

Background:  Although the use of continuous epidural infusion (CEI) and patient‐controlled epidural analgesia (PCEA) has become commonplace in pain management, there is still controversy regarding the relative effects of mass, volume and concentration of the local anaesthetic. This prospective study evaluated the influence of two concentrations of levobupivacaine on the quality of analgesia in two modes of delivery after lower abdominal surgery.

Methods:  Eighty‐two patients were randomly assigned to four groups to receive combined low thoracic epidural analgesia and general anaesthesia followed by post‐operative CEI or PCEA using 1.5 or 5 mg/ml levobupivacaine (15 mg/h in CEI and bolus 5 mg, lockout 20 min in PCEA). Sensory block, pain scores, levobupivacaine and rescue morphine consumption, motor blockade, haemodynamics, side‐effects and patient satisfaction were registered within 48 h.

Results:  The four groups were similar with regard to demographics, quality of analgesia, morphine consumption and satisfaction rate. No difference in the quality of analgesia was observed for the two modes of delivery with regard to the concentration of levobupivacaine, but the consumption of the local anaesthetic was higher in the CEI groups. The Bromage scores in the PCEA groups were reduced to zero for all except one patient, whereas eight patients presented scores of one or more in the CEI population.

Conclusion:  Levobupivacaine in thoracic epidurals provides an equal quality of post‐operative analgesia in low and high volume independent of the delivery mode, i.e. CEI or PCEA. This is in accordance with the assumption that the total dose of the local anaesthetic determines the quality of analgesia.
Evaluation of the new Viewmax laryngoscope in a simulated difficult airway
Authors: Leung Y. Y. , Hung C. T. , Tan S. T.
Published: April 2006

Background:  In this study, we evaluated the learning curve and performance of the Viewmax laryngoscope during simulated difficult laryngoscopy in an intubation manikin (Laerdal Airway Management Trainer).

Methods:  To determine the learning curve, 25 anaesthesiologists without previous experience with the Viewmax laryngoscope performed 10 successive intubations in an intubation manikin with a normal airway. Time to intubation and failed intubation attempts were recorded. Another manikin was modified to enable comparison of the Viewmax laryngoscope with Macintosh and McCoy laryngoscopes. The time to intubation, number of failed intubation attempts, modified Cormack and Lehane (MCL) laryngeal view grading, percentage of glottic opening (POGO score), use of gum elastic bougie and subjective rating of degree of difficulty were recorded.

Results:  The learning curve for the Viewmax laryngoscope showed a progressive decrease in time to successful intubation and reached a plateau at the sixth attempt. In simulated difficult laryngoscopy, the Viewmax laryngoscope demonstrated significantly better laryngeal view than the Macintosh and McCoy laryngoscopes in terms of MCL grading (Macintosh, P = 0.01; McCoy, P < 0.01) and POGO score (Macintosh, P < 0.01; McCoy, P < 0.01). The time required for intubation in simulated difficult laryngoscopy for the Viewmax laryngoscope was significantly longer than that for the Macintosh (P = 0.02) and McCoy (P < 0.01) laryngoscopes. There was no significant difference in the degree of difficulty, number of failed intubations and use of gum elastic bougie.

Conclusion:  When compared with the Macintosh and McCoy laryngoscopes in a manikin, the Viewmax laryngoscope appears to improve the view of the larynx but requires a longer time for tracheal intubation.
Effect of needle insertion site on ilioinguinal‐iliohypogastric nerve block in children
Authors: Kundra P. , Sivashanmugam T. , Ravishankar M.
Published: April 2006

Background:  Three different sites of needle insertion have been proposed for ilioinguinal‐iliohypogastric (ILIH) nerve block. This double‐blind study was designed to assess the quality of analgesia produced from these different sites.

Methods:  One hundred and thirty‐two children of ASA grade I and II were randomly allocated into four groups to receive no nerve block (control group, n = 30) or ILIH block at 1 cm inferio‐medial to the anterior superior iliac spine (ASIS) in group IM (n = 34), 1–2 cm medial to the ASIS in group M (n = 34) and 2 cm superio‐medial to the ASIS in group SM (n = 34) with 0.25 ml/kg of 0.25% bupivacaine after induction of anaesthesia. Pain was assessed using the All India Institute of Medical Sciences (AIIMS) pain discomfort scale (APDS) score. The amount and pattern of fentanyl consumed over the ensuing 24‐h period was noted.

Results:  APDS score and fentanyl requirement were similar in all the study groups but significantly higher until 8 h after surgery in the control group, P < 0.05. Twenty‐two out of 102 children in the study groups and all patients in the control group received additional fentanyl during the post‐operative period. Only 6 out of 22 children required additional fentanyl supplementation beyond the 30‐min interval. Overall failure rate of ILIH nerve block was 6%.

Conclusion:  ILIH block can be successfully accomplished from any point if the needle bevel lies between the two muscle planes above and below the internal oblique.
Desflurane vs. sevoflurane as the main inhaled anaesthetic for spontaneous breathing via a laryngeal mask for varicose vein day surgery: a prospective randomized study
Authors: Saros G. B. , Doolke A. , Anderson R. E. , Jakobsson J. G.
Published: April 2006

Background:  Sevoflurane has become widely used in day surgery; however, desflurane may be a valuable alternative even in this setting. This study compares emergence from anaesthesia for day surgery with spontaneous breathing using either desflurane or sevoflurane.

Methods:  This prospective, randomized, single‐blinded study examined 70 ASA III patients undergoing elective ambulatory varicose vein surgery. Primary endpoint was emergence time (cessation of anaesthetic gas to communicating). Secondary endpoints included post‐operative pain, nausea, time to discharge, and patient satisfaction. Patients were anaesthetized according to a standardized protocol including multimodal analgesia and antiemetic therapy and were randomized to receive sevoflurane or desflurane as the main anaesthetic while breathing spontaneously through a laryngeal mask airway. Fresh gas flow was oxygen in air 1 : 2 l/min.

Results:  Intra‐operative anaesthesia was uneventful apart from airway irritation observed in 5/35 desflurane and 1/35 sevoflurane patients. Emergence was 25–40% faster in patients anaesthetized with desflurane. Pain and post‐operative nausea and vomiting (PONV) were equally infrequent in both groups. Overall, patient satisfaction was high with no difference between the groups.

Conclusion:  Desflurane is associated with a faster emergence with no differences during the post‐operative course except a somewhat higher incidence of airway irritation.
Propofol formulated with long‐/medium‐chain triglycerides reduces the pain of injection by target controlled infusion
Authors: Suzuki H. , Miyazaki H. , Andoh T. , Yamada Y.
Published: April 2006

Background:  Propofol is a widely used intravenous anesthetic although its injection pain is a common and unpleasant problem. Long‐/medium‐chain triglyceride (LCT/MCT) propofol has been introduced, as its low free propofol content is expected to reduce injection pain compared with LCT propofol. Target controlled infusion (TCI) differs from conventional induction in the initial infusion pattern. During induction using TCI, we investigated injection pain caused by two propofol solutions with different triglyceride compositions.

Methods:  Fifty patients, ASA I–II, with adequate communicative ability, were randomly assigned to two groups. TCI was conducted with Diprifusor for LCT and with BeComSim (custom‐made software) for LCT/MCT. The target blood concentration was set at 4 μg/ml for both groups. At 30, 60, and 120 s after the infusion, patients were asked questions regarding the severity of pain on a 0–10 pain score. The total dose of propofol and the time required to induce anesthesia were also investigated.

Results:  The LCT/MCT propofol group had a larger number of pain‐free patients and showed lower severity of pain than the LCT group [the number of pain‐free patients being 11 and 3, respectively (P < 0.05), and median maximum pain being 0 and 4.5, respectively (P < 0.01)]. The dose and time required for induction were not significantly different between the groups (dose of 84 ± 27 and 80 ± 24 mg, respectively, and time of 119 ± 60 and 107 ± 55 s, respectively).

Conclusion:  Our study showed that the frequency and severity of pain during TCI induction with propofol could be significantly reduced using LCT/MCT propofol rather than LCT propofol.
Testing the directionality of evolution: the case of chydorid crustaceans
Authors: Adamowicz S. J. , Sacherová V.
Published: April 2006

Although trends are of central interest to evolutionary biology, it is only recently that methodological advances have allowed rigorous statistical tests of putative trends in the evolution of discrete traits. Oligomerization is one such proposed trend that may have profoundly influenced evolutionary pathways in many types of animals, especially arthropods. It is a general hypothesis that repeated structures (such as appendage segments and spines) tend to evolve primarily through loss. Although largely untested, this principle of loss is commonly invoked in morphological studies of crustaceans for drawing conclusions about the systematic placements of taxa and about their phylogeny. We present a statistical evaluation of this hypothesis using a molecular phylogeny and character matrix for a family of crustaceans, the Chydoridae, analysed using maximum likelihood methods. We find that a unidirectional (loss-only) model of character evolution is a very poor fit to the data, but that there is evidence of a trend towards loss, with loss rates of structures being perhaps twice the rates of gain. Thus, our results caution against assuming loss a priori, in the absence of appropriate tests for the characters under consideration. However, oligomerization, considered as a tendency but not a rule, may indeed have had ramifications for the types of functional and ecological shifts that have been more common during evolutionary diversification.
Efficacy of topical griseofulvin in treatment of tinea corporis
Authors: Kassem Mohamed A. A. , Esmat Samia , Bendas Eihab R. , El‐Komy Mohamed H. M.
Published: April 2006

Tinea infections are among the most common dermatological conditions throughout the world. Griseofulvin is a classical oral fungistatic antibiotic, active against Epidermophyton floccosum, Trichophyton and Microsporum species, the causative fungi of tinea corporis. To evaluate the efficacy of topical griseofulvin in the treatment of tinea circinata using three different vehicles for drug delivery. Sixteen patients with tinea circinata were instructed to apply either griseofulvin gel form in group A or a similar placebo gel for control group; a niosomal gel formulation of griseofulvin for group B or; a liposomal gel formulation of griseofulvin for group C. Patients were evaluated both clinically and mycologically after 3 weeks. Marked improvement was seen for groups A, B and C both clinically and mycologically while no improvement was observed in the placebo group. Mild and transient irritation was reported in four patients. Our results show that topical griseofulvin preparations may be effective and safe in treating tinea circinata and that further large‐scale studies may establish the high efficacy of the niosomal gel formulation.
Propagule vs. niche limitation: untangling the mechanisms behind plant species’ distributions
Authors: Moore Kara A. , Elmendorf Sarah C.
Published: April 2006

Distinguishing the roles of propagule limitation and niche requirements in controlling plant species distributions is important for understanding community structure, invasion, and restoration. We used species distribution models based on plant and environmental survey data to assess the strength of species’ affinities for particular environmental conditions. We hypothesized that species with statistically detectable environmental requirements were primarily niche‐limited, while species with weak habitat affinities were primarily propagule‐limited. We tested this hypothesis via a seeding experiment in which we compared species’ reproductive fitness in occupied and unoccupied sites. Species that appeared to be niche‐limited based on distribution models had lower fitness when planted in unoccupied sites, while species that models suggested were propagule‐limited had equivalent fitness when planted in occupied and unoccupied sites. Our results demonstrate that within a single community, both species limited primarily by niche availability or primarily by propagule availability can be identified using observational data.
Functional diversity: back to basics and looking forward
Authors: Petchey Owen L. , Gaston Kevin J.
Published: April 2006

Functional diversity is a component of biodiversity that generally concerns the range of things that organisms do in communities and ecosystems. Here, we review how functional diversity can explain and predict the impact of organisms on ecosystems and thereby provide a mechanistic link between the two. Critical points in developing predictive measures of functional diversity are the choice of functional traits with which organisms are distinguished, how the diversity of that trait information is summarized into a measure of functional diversity, and that the measures of functional diversity are validated through quantitative analyses and experimental tests. There is a vast amount of trait information available for plant species and a substantial amount for animals. Choosing which traits to include in a particular measure of functional diversity will depend on the specific aims of a particular study. Quantitative methods for choosing traits and for assigning weighting to traits are being developed, but need much more work before we can be confident about trait choice. The number of ways of measuring functional diversity is growing rapidly. We divide them into four main groups. The first, the number of functional groups or types, has significant problems and researchers are more frequently using measures that do not require species to be grouped. Of these, some measure diversity by summarizing distances between species in trait space, some by estimating the size of the dendrogram required to describe the difference, and some include information about species’ abundances. We show some new and important differences between these, as well as what they indicate about the responses of assemblages to loss of individuals. There is good experimental and analytical evidence that functional diversity can provide a link between organisms and ecosystems but greater validation of measures is required. We suggest that non‐significant results have a range of alternate explanations that do not necessarily contradict positive effects of functional diversity. Finally, we suggest areas for development of techniques used to measure functional diversity, highlight some exciting questions that are being addressed using ideas about functional diversity, and suggest some directions for novel research.
Multivariate dispersion as a measure of beta diversity
Authors: Anderson Marti J. , Ellingsen Kari E. , McArdle Brian H.
Published: April 2006

Beta diversity can be defined as the variability in species composition among sampling units for a given area. We propose that it can be measured as the average dissimilarity from individual observation units to their group centroid in multivariate space, using an appropriate dissimilarity measure. Differences in beta diversity among different areas or groups of samples can be tested using this approach. The choice of transformation and dissimilarity measure has important consequences for interpreting results. For kelp holdfast assemblages from New Zealand, variation in species composition was greater in smaller holdfasts, while variation in relative abundances was greater in larger holdasts. Variation in community structure of Norwegian continental shelf macrobenthic fauna increased with increases in environmental heterogeneity, regardless of the measure used. We propose a new dissimilarity measure which allows the relative weight placed on changes in composition vs. abundance to be specified explicitly.
Contending with Risk Selection in Health Insurance Markets in Germany
Authors: Glazer Jacob , McGuire Thomas G.
Published: April 2006

In many countries, competition among health plans or sickness funds raises issues of risk selection. Funds may discourage or encourage potential enrollees from joining, and these actions may have efficiency or fairness implications. This article reviews the experience in the U.S., and comments on the evidence for risk selection in Germany. There is little evidence that risk selection causes efficiency problems in Germany, but risk selection does lead to an inequality in contribution rates. A simple approach to equalizing contribution rates that does not involve risk adjustment is presented and discussed.
Ethnic Diversity and Perceptions of Safety in Urban Middle Schools
Authors: Juvonen Jaana , Nishina Adrienne , Graham Sandra
Published: April 2006

Students' perceptions of their safety and vulnerability were investigated in 11 public middle schools (more than 70 sixth-grade classrooms) that varied in ethnic diversity. Results of hierarchical linear modeling analyses indicate that higher classroom diversity is associated with feelings of safety and social satisfaction. African American (n = 511) and Latino (n = 910) students felt safer in school, were less harassed by peers, felt less lonely, and had higher self-worth the more ethnically diverse their classrooms were, even when controlling for classroom differences in academic engagement. Results at the school level were similar to those at the classroom level; higher ethnic diversity was associated with lower levels of self-reported vulnerability (but no difference in self-worth) in both fall and spring of sixth grade. In the spirit of Brown v. Board of Education, the current findings offer new empirical evidence for the psychological benefits of multiethnic schools.
Shared System for Ordering Small and Large Numbers in Monkeys and Humans
Authors: Cantlon Jessica F. , Brannon Elizabeth M.
Published: April 2006

There is increasing evidence that animals share with adult humans and perhaps human infants a system for representing objective number as psychological magnitudes that are an analogue of the quantities they represent. Here we show that rhesus monkeys can extend a numerical rule learned with the values 1 through 9 to the values 10, 15, 20, and 30, which suggests that there is no upper limit on a monkey's numerical capacity. Instead, throughout the numerical range tested, both accuracy and latency in ordering two numerical values were systematically controlled by the ratio of the values compared. In a second experiment, we directly compared humans' and monkeys' performance in the same ordinal comparison task. The qualitative and quantitative similarity in their performance provides the strongest evidence to date of a single nonverbal, evolutionarily primitive mechanism for representing and comparing numerical values.
Acting Intentionally and the Side-Effect Effect
Authors: Leslie Alan M. , Knobe Joshua , Cohen Adam
Published: April 2006

The concept of acting intentionally is an important nexus where theory of mind and moral judgment meet. Preschool children's judgments of intentional action show a valence-driven asymmetry. Children say that a foreseen but disavowed side effect is brought about “on purpose” when the side effect itself is morally bad, but not when it is morally good. This is the first demonstration in preschoolers that moral judgment influences judgments of whether something was done on purpose (as opposed to judgments of purpose influencing moral judgment). Judgments of intentionality are usually assumed to be purely factual. That these judgments are sometimes partly normative—even in preschoolers—challenges current understanding. Young children's judgments regarding foreseen side effects depend on whether the children process the idea that the character does not care about the side effect. As soon as preschoolers effectively process the theory-of-mind concept “not care that P,” children show the side-effect effect.
The Effect of Personal Relevance and Approach-Related Action Expectation on Relative Left Frontal Cortical Activity
Authors: Harmon-Jones Eddie , Lueck Lacey , Fearn Meghan , Harmon-Jones Cindy
Published: April 2006

Past research using a variety of methods has suggested that the frontal cortex is asymmetrically involved in the experience and expression of positive (or approach motivational) and negative (or withdrawal motivational) affects, with the left frontal region being involved in positive affects (or approach) and the right frontal region being involved in negative affects (or withdrawal). However, some studies have failed to replicate these effects, leaving many scientists questioning the meaning of the past supportive findings. To examine these inconsistencies in results, we tested the hypothesis that increasing the personal relevance of the stimuli and approach motivational intensity would increase relative left frontal activation. Results supported the predictions. Moreover, by showing the predicted effects with anger-inducing stimuli, the results demonstrated that motivational direction, rather than affective valence, accounts for asymmetrical frontal cortical activity.
An anatomical study of the buccinator muscle fibres that extend to the terminal portion of the parotid duct, and their functional roles in salivary secretion
Authors: Kang Hyo‐Chang , Kwak Hyun‐Ho , Hu Kyung‐Seok , Youn Kwan‐Hyun , Jin Guang‐Chun , Fontaine Christian , Kim Hee‐Jin
Published: April 2006

Until now there has been no definitive anatomical study describing the area where the parotid duct enters the buccinator muscle. In this study, we performed anatomical and histological examinations to investigate the relationship between the parotid duct and the buccinator muscle. Thirty specimens (including the buccinator and the terminal portion of the parotid duct) were obtained from embalmed Korean cadavers. Dissection was performed on 22 of these specimens, and the remaining eight specimens were prepared for histological examination and stained with haematoxylin–eosin or Gomori trichrome. In all specimens, small, distinct muscle fibres originating from the buccinator muscle extended to and inserted into the terminal portion of the parotid duct. The topography of these fibres varied, and we classified them into three categories according to where they originated. Type I buccinator muscle fibres, which inserted into the terminal portion of the parotid duct, originated simultaneously from the anterior and posterior aspects of the duct (ten cases, 45.5%). Type II fibres originated from the anterior aspect of the duct and inserted into the anterior side of the duct (seven cases, 31.8%). Type III fibres originated from the posterior aspect of the parotid duct and ran anteriorly toward the duct (five cases, 22.7%). These results were confirmed in the histological examination of all eight specimens. Based on these findings, we have proposed a tentative description of the physiological role of the buccinator muscle fibres in salivary secretion and in the formation of the sialoliths.
Attenuation of MPTP‐induced neurotoxicity and locomotor dysfunction in Nucling‐deficient mice via suppression of the apoptosome pathway
Authors: Teng Xichuan , Sakai Takashi , Liu Li , Sakai Rika , Kaji Ryuji , Fukui Kiyoshi
Published: April 2006

1‐Methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)‐induced neurotoxicity is one of the experimental models most commonly used to study the pathogenesis of Parkinson's disease (PD). Although the biochemical mechanisms underlying the cell death induced by MPTP remain to be clarified, it has been found that the mitochondrial apoptotic signaling pathway plays an important role in the neurotoxicity of MPTP. Nucling is a novel type of apoptosis‐associated molecule, essential for cytochrome c, apoptosis protease activating factor 1 (Apaf‐1), pro‐caspase‐9 apoptosome induction and caspase‐9 activation following pro‐apoptotic stress. Here we found that Nucling‐deficient mice treated with MPTP did not exhibit locomotor dysfunction in an open‐field test. The substantia nigra dopaminergic neurons of Nucling‐deficient mice were resistant to the damaging effects of the neurotoxin MPTP. Up‐regulated expression of apoptosome was attenuated in Nucling‐deficient mice treated with MPTP. These results indicate an important role for Nucling in MPTP‐induced neuronal degeneration and suggest that the suppression of Nucling would be of therapeutic benefit for the treatment of neurodegeneration in PD.
Forearm blood flow and oxygen consumption in patients with bilateral repetitive strain injury measured by near‐infrared spectroscopy
Authors: Brunnekreef Jaap J. , Oosterhof Jan , Thijssen Dick H. J. , Colier Willy N. J. M. , Van Uden Caro J. T.
Published: April 2006

Despite the social impact of repetitive strain injury (RSI), little is known about its pathophysiological mechanism. The main objective of this study was to assess the local muscle oxygenation (mVO2) and blood flow (mBF) of the forearm in individuals with RSI during isometric contractions of the forearm. We employed the non‐invasive optical technique near‐infrared spectroscopy to assess forearm VO2 and BF. These variables were assessed at 10%, 20%, and 40% of their individual maximal voluntary strength. Twenty‐two patients with RSI symptoms in both arms (bilateral RSI) and 30 healthy age‐matched subjects participated in this cross‐sectional study. The results showed lower mVO2 during exercise and a reduced mBF after exercise. The results suggest that mVO2 and mVO2 are lower in the forearms of individuals with RSI compared with their controls at similar working intensities. This finding indicates that the underlying vasculature may be impaired. Although these findings contribute to the understanding of RSI, future research is necessary to further unravel the mechanisms of this area.
Cardiac pumping capability in patients with peripheral vascular disease
Authors: Hodges L. D. , Sandercock G. R. H. , Das S. K. , Brodie D. A.
Published: April 2006

Introduction:  Peripheral vascular disease (PVD) is a condition characterized by atherosclerotic occlusive disease of the lower extremities, low functional capacity and low exercise tolerance. Less empirical data are available concerning the cardiovascular response to maximum exercise tests in patients with PVD. The purpose of this study was to examine cardiovascular variables in patients with peripheral vascular disease.

Methods:  Fifty patients (67 ± 9 years) completed an incremental exercise test (2 min stages, 3·2 km h−1, with increases of 2% every 2 min) to maximum claudication pain. Maximal oxygen consumption () was assessed on a breath‐by‐breath basis by online expiratory gas analysis (CardiO2, Medical Graphics Co.). Blood pressure was recorded at peak exercise. Following a 30‐min rest period, patients exercised at the highest level attained during the first test and cardiac output () was measured using the exponential non‐invasive rebreathing method. Cardiac power output peak (CPOpeak) in Watts (W), was then computed.

Results:  Mean ± SD values were; 13·85 ± 4·14 ml kg min−1; maximal walk time 357 ± 227 s; peak mean arterial pressure 127 ± 15 mmHg; 9·8 ± 2·39 (l min−1); CPO 2·86 ± 0·87 W.

Conclusion:  Patients with peripheral vascular disease demonstrate attenuated levels of cardiovascular capacity. This group of patients should be given exercise therapy in order to improve cardiovascular status and ambulatory function.
Comparison of two physical sensor models for satellite images: Position–Rotation model and Orbit–Attitude model
Authors: Kim Taejung , Dowman Ian
Published: April 2006

The main objective of this paper is to compare two types of physical sensor models of linear pushbroom satellite images: one that uses position and rotation angles as model parameters and one that uses orbit and attitude angles as model parameters. Comparison is carried out by two accuracy measures: the accuracy of bundle adjustments and the accuracy of estimating exterior orientation parameters. The first measure has been used widely to indicate the mapping accuracy of sensor models. It is argued that the second measure is also important for certain applications. The two types were implemented with different sets of unknown parameters and tested with two KOMPSAT‐1 Earth Observing Camera (EOC) scenes and GPS‐derived control points. In terms of the first measure the two models produced similar results whereas in terms of the second measure the one based on orbit and attitude outperformed the other. It seems better to use this model if one wishes to retrieve satellite orbit or attitude through bundle adjustments.
Three-Dimensional Power: A Discussion of Steven Lukes' Power: A Radical View
Authors: Dowding Keith
Published: April 2006

Lukes' third dimension of power exists where people are subject to domination and acquiesce in that domination. The intentional stance allows us to predict and explain others' behaviour in ways that those agents may not recognise. It denies agents' privileged access to their own reasons for actions. Using the intentional stance we can understand how agents may acquiesce in their own domination. We can also make distinctions between those who dominate knowingly and those who dominate without realising they do so. It allows us to distinguish morally such cases and to understand the power structure without falling into the Foucaultian trap of seeing all social relationships in the same relativistic light and where all – dominant and dominated alike – are subject to the same power relations and moral responsibility.
Medications Associated with Probable Medication Overuse Headache Reported in a Tertiary Care Headache Center Over a 15‐Year Period
Authors: Meskunas Chelsea A. , Tepper Stewart J. , Rapoport Alan M. , Sheftell Fred D. , Bigal Marcelo E.
Published: April 2006

Objectives.—To evaluate the substances associated with medication overuse headache (MOH) in a headache center, over the course of the past 15 years.

Background.—The acute treatment of migraine has substantially changed over the past 15 years, and therefore, the substances associated with MOH may have changed as well.

Methods.—We randomly reviewed charts of subjects seen during the years of 2005, 2000, 1995, and 1990, to identify substances associated with MOH. Since the criteria proposed by the second edition of the International Classification of Headache Disorders require causal attribution, demonstrated by improvement after withdrawal (and this was not assessed in this study), herein we refer to probable MOH (PMOH). We contrasted the substances associated with PMOH over the studied years.

Results.—Our sample consists of 1200 individuals, 300 per year of interest. The proportions of subjects with a diagnosis of PMOH remained stable over the years, varying from 64% of all cases seen in the center in 1990, to 59.3% in 2005. We found a significant decrease in the relative frequency of probable ergotamine overuse headache (from 18.6% to 0%, P < .0001), and in probable combination analgesic overuse headache (from 42.2% to 13.6%, P < .0001). The differences were not significant for opioid overuse headache. The relative frequency increased significantly for the triptans (from 0% to 21.6%, P < .0001), simple analgesics (from 8.8% to 31.8%, P < .05), and for combinations of acute medications (from 9.8% to 22.7%, P= .01).

Conclusion.—While overuse of acute medications remains an important problem in the tertiary care arena, the substances associated with the overuse have dramatically changed over the past 15 years. Educational initiatives should emphasize that the newer specific acute migraine medications (triptans) may also be associated with PMOH.
Lung Cancer Presenting With Unilateral Facial Pain: Remission After Laryngeal Nerve Palsy
Authors: Palmieri Antonio
Published: April 2006

A 39‐year‐old woman presented with a 2‐month history of intractable, left‐sided facial pain. A CT scan of the thorax disclosed a large lung mass surrounding supra‐aortic vessels and hilus. The symptoms underwent a rapid and spontaneous remission after laryngeal nerve palsy with dysphonia developed. Referred facial pain secondary to the compression of the vagus nerve can rarely be the first manifestation of an underlying lung cancer. All cases of unexplained unilateral facial pain should be investigated for a mediastinal pathology, especially in smoker subjects.
The Peer Context of Adolescent Substance Use: Findings from Social Network Analysis
Authors: Ennett Susan T. , Bauman Karl E. , Hussong Andrea , Faris Robert , Foshee Vangie A. , Cai Li , DuRant Robert H.
Published: April 2006

To examine the peer context of adolescent substance use, social network analysis was used to measure three domains of attributes of peer networks: social embeddedness, social status, and social proximity to substance users. The sample was a panel of 5,104 sixth, seventh, and eighth graders in three public school systems surveyed every 6 months for five assessments. Hierarchical generalized linear models showed that adolescents less embedded in the network, with greater status, and with closer social proximity to peer substance users were more likely to use substances. Also, adolescents in less dense networks and networks with higher smoking prevalence were more likely to smoke and use marijuana. Results establish the utility of social network analysis for measuring peer context and indicate that conventionality of relationships—having friends in the network, being liked but not too well liked, and having fewer friends who use substances—is most beneficial.
Mechanisms involved in the enhancement of osteoclast formation by enamel matrix derivative
Authors: Itoh N. , Kasai H. , Ariyoshi W. , Harada E. , Yokota M. , Nishihara T.
Published: April 2006

Background and Objective:  Enamel matrix derivative (EMD) is used clinically to promote periodontal tissue regeneration, and it has been reported that EMD can induce the formation of osteoclasts in mouse marrow cultures. In the present study, we investigated the mechanisms of EMD‐induced osteoclast formation using a mouse monocytic cell line, RAW 264.7.

Material and Methods:  Bioactive fractions were purified from EMD by reverse‐phase HPLC using a C18 hydrophobic support, following which RAW 264.7 cells were cultured with EMD or its purified fractions in the presence of receptor activator of nuclear factor‐κB ligand (RANKL) for 8 d. Following staining with tartrate‐resistant acid phosphatase (TRAP), TRAP‐positive multinucleated cells were counted. The expression of receptor activator of nuclear factor‐κB (RANK), as well as phosphorylation of extracellular signal‐regulated kinase (ERK) and p38 mitogen‐activated protein (MAP) kinase, in RAW 264.7 cells were detected using immunoblotting. To determine whether EMD has an effect on osteoclast function, differentiated RAW 264.7 cells were cultured on Osteologic™ Multitest slides with RANKL in the presence of EMD.

Results:  Purified EMD fractions (fraction numbers 21–25; EMD peak 2) were found to enhance the formation and function of RAW 264.7 cells induced by RANKL. Moreover, EMD peak 2 enhanced the levels of phosphorylation of ERK p38 and RANK in RAW 264.7 cells stimulated with RANKL.

Conclusion:  Our results indicate that EMD induces the formation of osteoclasts through interaction with RANKL, while ERK and p38 MAPK may play a critical role in the enhancement of osteoclast formation in RAW 264.7 cells.
VALUE OF A SINGLE‐SHOT TURBO SPIN‐ECHO PULSE SEQUENCE FOR ASSESSING THE ARCHITECTURE OF THE SUBARACHNOID SPACE AND THE CONSTITUTIVE NATURE OF CEREBROSPINAL FLUID
Authors: PEASE ANTHONY , SULLIVAN STACEY , OLBY NATASHA , GALANO HEATHER , CERDA‐GONZALEZ SOPHIA , ROBERTSON IAN D. , GAVIN PATRICK , THRALL DONALD
Published: April 2006

Three case history reports are presented to illustrate the value of the single‐shot turbo spin‐echo pulse sequence for assessment of the subarachnoid space. The use of the single‐shot turbo spin‐echo pulse sequence, which is a heavily T2‐weighted sequence, allows for a rapid, noninvasive evaluation of the subarachnoid space by using the high signal from cerebrospinal fluid. This sequence can be completed in seconds rather than the several minutes required for a T2‐fast spin‐echo sequence. Unlike the standard T2‐fast spin‐echo sequence, a single‐shot turbo spin‐echo pulse sequence also provides qualitative information about the protein and the cellular content of the cerebrospinal fluid, such as in patients with inflammatory debris or hemorrhage in the cerebrospinal fluid. Although the resolution of the single‐shot turbo spin‐echo pulse sequence images is relatively poor compared with more conventional sequences, the qualitative information about the subarachnoid space and cerebrospinal fluid and the rapid acquisition time, make it a useful sequence to include in standard protocols of spinal magnetic resonance imaging.
HELICAL COMPUTED TOMOGRAPHIC ANGIOGRAPHY OF THE NORMAL CANINE PANCREAS
Authors: CÁCERES ANA V. , ZWINGENBERGER ALLISON L. , HARDAM ERIN , LUCENA JOSÉ M. , SCHWARZ TOBIAS
Published: April 2006

Helical abdominal computed tomography (CT) was performed in nine normal beagle‐mix dogs. Following cephalic vein injection of ionic iodinated contrast medium via power injector (rate 5 ml/s) dual‐phase CT was performed in all dogs. A delayed scan was performed in five dogs between 5 and 13 min after the contrast medium injection. The median time of appearance of contrast medium in the aorta and gastroduodenal artery was 6.3 and 7 s, post start injection and 12 and 12.2 s in the gastroduodenal and portal vein, resulting in a purely arterial pancreatic time window of 5–6 s. Pancreatic veins and parenchyma remained enhanced until the end of the dynamic scan (40 s). The pancreatic parenchyma showed heterogeneous arterial and homogenous venous contrast enhancement which was slightly hypoattenuating compared to the liver. Delayed scans provided best delineation of the pancreas from the liver. The common bile duct could be identified ventral and to the right of the portal vein joining the dorsomedial aspect of proximal duodenum. Because of the very short time window and variable onset of pure arterial enhancement careful planning of dual‐phase studies with previous dynamic CT is recommended. Dual‐phase CT angiography enables assessment of the arterial supply, parenchymal perfusion and venous drainage of the canine pancreas.
Constitutively active α subunits of Gq/11 and G12/13 families inhibit activation of the pro‐survival Akt signaling cascade
Authors: Wu Eddy H. T. , Tam Becky H. L. , Wong Yung H.
Published: April 2006

Accumulating evidence indicates that G protein signaling plays an active role in the regulation of cell survival. Our previous study demonstrated the regulatory effects of Gi/o proteins in nerve growth factor‐induced activation of pro‐survival Akt kinase. In the present study we explored the role of various members of the Gs, Gq/11 and G12/13 subfamilies in the regulation of Akt in cultured mammalian cells. In human embryonic kidney 293 cells transiently expressing constitutively active mutants of Gα11, Gα14, Gα16, Gα12, or Gα13 (Gα11QL, Gα14QL, Gα16QL, Gα12QL and Gα13QL, respectively), basal phosphorylation of Akt was attenuated, as revealed by western blotting analysis using a phosphospecific anti‐Akt immunoglobulin. In contrast, basal Akt phosphorylation was unaffected by the overexpression of a constitutively active Gαs mutant (GαsQL). Additional experiments showed that Gα11QL, Gα14QL, Gα16QL, Gα12QL and Gα13QL, but not GαsQL, attenuated phosphorylation of the Akt‐regulated translation regulator tuberin. Moreover, they were able to inhibit the epidermal growth factor‐induced Akt activation and tuberin phosphorylation. The inhibitory mechanism of Gq family members was independent of phospholipase Cβ activation and calcium signaling because Gα11QL, Gα14QL and Gα16QL remained capable of inhibiting epidermal growth factor‐induced Akt activation in cells pretreated with U73122 and the intracellular calcium chelator, BAPTA/AM. Finally, overexpression of the dominant negative mutant of RhoA blocked Gα12QL‐ and Gα13QL‐mediated inhibition, suggesting that activated Gα12 and Gα13 inhibit Akt signaling via RhoA. Collectively, this study demonstrated the inhibitory effect of activated Gα11, Gα14, Gα16, Gα12 and Gα13 on pro‐survival Akt signaling.
The Causal Structure of Land Price Determinants
Authors: Awokuse Titus O. , Duke Joshua M.
Published: April 2006

This paper investigates causation contemporaneously and dynamically to elucidate the persistent lack of agreement about what “causes” changes in farmland prices. The analysis synthesizes and extends previous investigations in this area by employing a combination of directed acyclic graphs (DAG), a recently developed modeling technique, and cointegrated VAR model. DAG theory and algorithms offer a powerful tool for analyzing contemporaneous causal relationships among economic variables. The results from this study confirm the importance of measures of return to farming, financial (credit market constraints) and/or macroeconomic activity as significant determinants of fluctuations in farmland prices.

Le présent article examine la causalité de façon contemporaine et dynamique pour élucider le manque persistant de consensus quant aux causes de variations du prix des terres. L'analyse est une synthèse des études antérieures de même qu'un prolongement effectuéà l'aide d'une combinaison de graphes acycliques orientés (DAG), technique de modélisation mise au point récemment, et du modèle VAR cointégré. La théorie des DAG et les algorithmes constituent un outil puissant pour analyser les liens causals contemporains des variables économiques. Les résultats confirment l'importance du rendement de l'activité agricole, des contraintes financières (contraintes du crédit) et/ou de l'activité macroéconomique comme déterminants significatifs des variations du prix des terres agricoles.
Green Subsidies in Agriculture: Estimating the Adoption Costs of Conservation Tillage from Observed Behavior
Authors: Kurkalova Lyubov , Kling Catherine , Zhao Jinhua
Published: April 2006

Due to payoff uncertainties combined with risk aversion and/or real options, farmers may demand a premium in order to adopt conservation tillage practices, over and above the compensation for the expected profit losses (if any). We propose a method of directly estimating the financial incentives required for adopting conservation tillage and distinguishing between the expected payoff and premium of adoption based on the observed behavior. We find that the premium may play a significant role in farmers' adoption decisions. In an application to the state of Iowa, we find that if a uniform conservation tillage adoption subsidy program were offered in 1992, over 86% of the subsidy program payments would be an income transfer to existing and low‐cost adopters.

En raison des incertitudes quant aux gains, combinées à l'aversion pour le risque et/ou aux options réelles, les agriculteurs pourraient réclamer une prime pour l'adoption de méthodes culturales de conservation du sol, une prime qui serait supérieure à l'indemnisation offerte en cas de perte de gains prévue (s'il y a lieu). Nous avons proposé une méthode fondée sur le comportement observé qui permet une estimation directe des incitatifs financiers exigés pour adopter les méthodes culturales de conservation du sol et qui fait une distinction entre les gains prévus et la prime d'adoption. Nous avons constaté qu'une prime pourrait influencer considérablement les décisions des agriculteurs quant à l'adoption de méthodes culturales de conservation du sol. En Iowa par exemple, nous avons trouvé que, si un programme de subventions uniforme pour l'adoption de méthodes de conservation du sol avait été offert en 1992, plus de 86 p. 100 des paiements du programme de subvention aurait constitué un transfert de revenus aux adopteurs existants et à faibles coûts.
Aortic and iliac thrombosis associated with angiosarcoma of skeletal muscle in a dog
Authors: Wray J. D. , Bestbier M. , Miller J. , Smith K. C.
Published: April 2006

A seven‐year‐old, neutered male greyhound was presented with a history of episodic shifting hindlimb lameness and pain. Ischaemic necrosis of areas of the hindlimb digits and skin and a firm swelling within the medial right thigh musculature were found on physical examination. Investigation demonstrated thrombosis of the terminal aorta and right external iliac artery with ischaemic necrosis of muscular and dermal tissue distal to the sites of thrombosis. The dog was euthanased due to poor prognosis. Necropsy findings were of a poorly differentiated invasive sarcoma of the skeletal muscle of the proximal right hindlimb, thrombosis of the aorta and right external iliac artery and secondary renal glomerulopathy. Immunohistochemistry of the neoplastic tissue indicated angiosarcoma based on expression of CD31 and factor VIII‐related antigen. Thrombosis was considered likely to be due to systemic hypercoagulability because of the presence of altered flow characteristics and endothelial damage in the vascular tumour bed. Aortoiliac thrombosis, paraparesis and hindlimb ischaemia are unusual sequelae of angiosarcoma in the dog.
Prevalence of fetal resorption in stray dogs in Yucatan, Mexico
Authors: Ortega‐Pacheco A. , Rodriguez‐Buenfil J. C. , Segura‐Correa J. C. , Montesde Oca‐González A. R. , Jiménez‐Coello M.
Published: April 2006

Objectives: To determine the prevalence of fetal resorption in 77 pregnant bitches and its association with the age, size and body condition score of the bitch and to determine the frequency of transuterine migration of embryos.

Methods: The number and position of embryos or fetuses and placental zones were registered postmortem. The prevalence of fetal losses was determined by comparing the number of corpora lutea with the number of embryos or fetuses in each bitch. The prevalence of transuterine migration of embryos was determined by correlating the number of fetuses in each horn and the number of corpora lutea in the ipsilateral ovary.

Results: Fetal resorption zones were demonstrated in 42·9 per cent of the bitches. However, pregnancy continued in 84·9 per cent of cases. Of the fetal losses, 25·9 per cent were determined by counting the number of corpora lutea and viable embryos or fetuses. Young bitches tended to have a higher probability of fetal resorption than adult bitches (P<0·06). The presence of fetal resorption zones was not associated with size or body condition. Transuterine migration of embryos had occurred in 15·8 per cent of the bitches.

Clinical Significance: This study demonstrated that embryo resorption is a normal event in the bitches, with a higher prevalence than previously thought.