bluuebunny/crossref_metadata_2025 huggingface dataset:
Seeking long‐term relationship: axon and target communicate to organize synaptic differentiation
Authors: Fox Michael A. , Umemori Hisashi
Published: April 2006

Synapses form after growing axons recognize their appropriate targets. The subsequent assembly of aligned pre and postsynaptic specializations is critical for synaptic function. This highly precise apposition of presynaptic elements (i.e. active zones) to postsynaptic specializations (i.e. neurotransmitter receptor clusters) strongly suggests that communication between the axon and target is required for synaptic differentiation. What trans‐synaptic factors drive such differentiation at vertebrate synapses? First insights into the answers to this question came from studies at the neuromuscular junction (NMJ), where axon‐derived agrin and muscle‐derived laminin β2 induce post and presynaptic differentiation, respectively. Recent work has suggested that axon‐ and target‐derived factors similarly drive synaptic differentiation at central synapses. Specifically, WNT‐7a, neuroligin, synaptic cell adhesion molecule (SynCAM) and fibroblast growth factor‐22 (FGF‐22) have all been identified as target‐derived presynaptic organizers, whereas axon‐derived neuronal activity regulated pentraxin (Narp), ephrinB and neurexin reciprocally co‐ordinate postsynaptic differentiation. In addition to these axon‐ and target‐derived inducers of synaptic differentiation, factors released from glial cells have also been implicated in regulating synapse assembly. Together, these recent findings have profoundly advanced our understanding of how precise appositions are established during vertebrate nervous system development.
Stage of Change for Making an Informed Decision about Medicare Health Plans
Authors: Levesque Deborah A. , Cummins Carol O. , Prochaska Janice M. , Prochaska James O.
Published: April 2006

Objective. To assess the applicability of the transtheoretical model of change (TTM) to informed choice in the Medicare population.

Data Sources/Study Setting. Two hundred and thirty‐nine new Medicare enrollees randomly selected from the Center for Medicare and Medicaid Services' October 2001 Initial Enrollee File, a repository of data for persons who are going to turn 65 and become entitled to enroll in Medicare in the next 3 months.

Study Design. Study participants completed TTM measures of stage of change, decisional balance, and self‐efficacy for informed choice, as well as measures of Medicare knowledge, perceived knowledge, and information seeking. Model testing was conducted to determine whether well‐established relationships between stage of change, decisional balance, and self‐efficacy replicate for informed choice in the Medicare population, and whether Medicare knowledge and information‐seeking increase across the stages.

Data Collection/Extraction Methods. Survey data were collected using mail surveys with telephone follow‐up for nonresponders.

Principal Findings. Predicted relationships were established between stage of change for informed choice and decisional balance, self‐efficacy, Medicare knowledge, and information seeking. The amount of variance accounted for by stage of change for informed choice was larger than that found for smoking cessation, where the TTM has had its greatest successes.

Conclusions. The methods and findings lay the groundwork for development of TTM‐based interventions for Medicare beneficiaries, and provide a prototype for the application of the TTM to informed decision making among other types of consumers who are being asked to take more responsibility for their health care.
Working Memory and Decision‐Making Biases in Young Adults With a Family History of Alcoholism: Studies from the Oklahoma Family Health Patterns Project
Authors: Lovallo William R. , Yechiam Eldad , Sorocco Kristen H. , Vincent Andrea S. , Collins Frank L.
Published: April 2006

Background: Alcohol misuse is more common in persons with a family history of alcoholism (FH+) than in those with no such history (FH−). Among FH+, behavioral disinhibition and male sex seem to signal the presence of an increased risk.

Methods: This study examined cognitive and behavioral characteristics of 175 nonabusing 18‐ to 30‐year‐olds, 87 FH+ and 88 FH−, who were further characterized by their degree of behavioral disinhibition using the Sociability scale of the California Personality Inventory. Working memory and decision making were tested using the Stroop Color‐Word Test and the Iowa Gambling Task, a simulated card game.

Results: Persons with a family history of alcoholism who were behaviorally disinhibited displayed significantly greater interference on the Stroop task than the other subgroups. On the Iowa Gambling Task, FH+ males, but not the females, were significantly more attentive to financial gains than other subgroups, and they had greater consistency in their choice behaviors.

Conclusions: Persons with a family history of alcoholism, in combination with behavioral disinhibition, appears to signal working memory deficits and in combination with male sex indicates an attraction to the rewarding aspects of a risk‐taking challenge. These findings are not secondary to heavy exposure to alcohol or other drugs, but instead reflect intrinsic risk‐related familial and personal characteristics of the subjects.
Influence of Subjective Intoxication, Breath Alcohol Concentration, and Expectancies on the Alcohol‐Aggression Relation
Authors: Giancola Peter R.
Published: April 2006

Background: The purpose of this study was to investigate the influence of subjective intoxication, alcohol‐aggression expectancies, and breath alcohol concentration (BrAC) on intoxicated aggression in men and women while controlling for dispositional aggressivity.

Methods: Subjects were 328 (163 men and 165 women) healthy social drinkers between 21 and 35 years of age. Following the consumption of either an alcohol or an active placebo beverage, subjects were tested on a modified version of the Taylor Aggression Paradigm in which mild electric shocks were received from, and administered to, a fictitious opponent during a competitive task. Levels of subjective intoxication and BrAC were measured immediately before subjects began the aggression task. Aggressive behavior was operationalized as the shock intensities administered to the fictitious opponent under conditions of low and high provocation.

Results: Subjective intoxication ratings were not related to aggressive behavior for either men or women. Alcohol‐aggression expectancies were related to aggression for men, but this effect was rendered nonsignificant when controlling for dispositional aggressivity, which in turn, was significantly related to the dependent variables for both men and women. Finally, BrAC was also related to aggression above and beyond the effects of dispositional aggressivity, yet only for men.

Conclusions: Taken as a whole, this study suggests that intoxicated aggression is primarily the result of alcohol's pharmacological properties in conjunction with an aggressive disposition.
Chemical Dependency Patients with Cooccurring Psychiatric Diagnoses: Service Patterns and 1‐Year Outcomes
Authors: Chi Felicia W. , Satre Derek D. , Weisner Constance
Published: April 2006

Background: Improving services and treatment outcomes for individuals with cooccurring alcohol and drug use disorders and psychiatric conditions has been a critical challenge to clinicians and policy makers. This study examined 1‐year outcomes for individuals entering chemical dependency (CD) treatment with and without cooccurring psychiatric diagnoses targeted by California parity legislation. Among those with cooccurring conditions (i.e., dual‐diagnosis patients), we examined a model including individual characteristics, treatment services, and extratreatment characteristics to understand CD outcome predictors in this population. We hypothesized that longer CD treatment duration and receiving psychiatric services would predict higher abstinence levels. In particular,patterns of psychiatric services (amount of services, receiving a critical dose, or receiving services concurrently with CD treatment) were assessed in relation to outcome.

Methods: We examined abstinence rates 1 year after intake for 747 adults with and without cooccurring conditions. Among dual‐diagnosis patients, logistic regression was used to examine predictors of abstinence.

Results: At baseline, dual‐diagnosis patients (N=104) had higher levels of medical, family, and employment problems than others. They had similar CD retention and received more psychiatric services during the year after intake and had comparable CD outcomes at 1 year. Length of stay in CD treatment, hours of psychiatric services, number of months with concurrent CD and psychiatric services, and number of 12‐step meetings attended were independent predictors of abstinence for dual diagnosis patients.

Conclusions: Chemical dependency outcomes in patients with cooccurring psychiatric conditions were positively associated with the number and patterning of services. Receiving psychiatric services concurrently with CD treatment may be beneficial for dual‐diagnosis patients. Future studies should examine how best to integrate services to optimize treatment outcomes.
Impact of different hold time before addition of platelet additive solution on the in vitro quality of apheresis platelets
Authors: Ringwald Jürgen , Haager Benedikt , Krex Daniel , Zimmermann Robert , Strasser Erwin , Antoon Marc , De Schrijver Eddy , Eckstein Reinhold
Published: April 2006

BACKGROUND:  The quality of platelets (PLTs) stored in PLT additive solution (PAS) is dependent on the type and proportion of the used PAS. No data are available as to whether a different hold time before the addition of PAS to hyperconcentrated PLT suspensions has an impact on PLT quality. The in vitro quality between single‐donor PLT concentrates was compared with two different hold times with two PASs.

STUDY DESIGN AND METHODS:  On two occasions, 6 × 1011 PLTs in 150 mL of plasma were collected from 20 blood donors. The units were split into two equal parts, and 140 mL of PAS‐II or PAS‐IIIM (randomized sequence) was added after 2 or 8 hours resulting in a PAS proportion of 65 percent. On Days 1, 5, and 7, glucose and lactate concentration, pH value, PLTs’ P‐selectin expression, response to hypotonic shock, and release of transforming growth factor‐β1 were determined.

RESULTS:  On all days, the lactate concentrations were higher and pH values were lower in units with an 8‐hour hold time, whereas the results of in vitro tests relating to the in vivo viability and activation of PLTs were similar for both groups. PAS‐IIIM–stored PLTs showed a lower glycolytic activity and better results in all performed in vitro tests than PAS‐II–stored PLTs.

CONCLUSIONS:  Although the metabolism of glucose was enhanced during hold time, the differences between both hold time groups are not meaningful from a biological viewpoint. Therefore, an 8‐hour hold time is feasible. PLT storage in PAS‐IIIM results in a PLT in vitro quality superior to that of PLTs stored in PAS‐II.
The Role of Sodium Channel Current in Modulating Transmural Dispersion of Repolarization and Arrhythmogenesis
Authors: ANTZELEVITCH CHARLES , BELARDINELLI LUIZ
Published: April 2006

Ventricular myocardium in larger mammals is composed of three distinct cell types: epicardial, M, and endocardial cells. Epicardial and M cell, but not endocardial cell, action potentials have a prominent Ito‐mediated notch. M cells are distinguished from the other cell types in that they display a smaller IKs, but a larger late INa and INa–Ca. These ionic differences may account for the longer action potential duration (APD) and steeper APD‐rate relationship of the M cell. The difference in the time course of repolarization of phase 1 and phase 3 contributes to the inscription of the electrocardiographic J wave and T wave, respectively. These repolarization gradients are modulated by electrotonic interactions, [K+]o, and agents or mutations that alter net repolarizing current. An increase in late INa, as occurring under a variety of pathophysiological states or in response to certain toxins, leads to a preferential prolongation of the M cell action potential, thus prolonging the QT interval and increasing transmural dispersion of repolarization (TDR), which underlies the development of torsade de pointes (TdP) arrhythmias. Agents that reduce late INa are effective in reducing TDR and suppressing TdP. A reduction in peak INa or an increase in net repolarizing current in the early phases of the action potential can lead to a preferential abbreviation of the action potential of epicardium in the right ventricle, and thus the development of a large TDR, phase 2 reentry, and polymorphic ventricular tachycardia associated with the Brugada syndrome.
Bradycardia‐Mediated Ventricular Electrical Remodeling
Authors: GROSS GIL J.
Published: April 2006

Bradycardic states are associated with myocardial electrical remodeling predisposing to potentially lethal ventricular tachydysrhythmias. We used a novel model of complete heart block (CHB) in the rabbit to test the hypothesis that ventricular activation rate is the primary determinant of early bradycardic electrical remodeling. Chronic endocardial right ventricular demand (VVI) pacing was applied at either the near‐physiologic rate of 280 beats/min or at the bradycardic rate of 140 beats/min, beginning immediately after transcatheter radiofrequency AV node ablation. A third group of animals underwent sham ablation and served as non‐paced, normal sinus rhythm controls. The major finding of this study was that electrical remodeling was established within 8 days of CHB induction in the bradycardic animals, but was not observed in either of the other 2 groups. Bradycardic animals had significant QT interval prolongation and biventricular downregulation of the delayed rectifier K+ currents, IKr and IKs. The Ca2+‐independent transient outward K+ current, Ito, and the inwardly rectifying K+ current, IK1, were unaffected. This paper highlights these findings in the context of a literature‐based review of heart rate‐dependent remodeling of the mammalian myocardium, summarizing the current state of knowledge and describing future challenges.
Fabrication and Characterization of Dual‐Channeled Zirconia Ceramic Scaffold
Authors: Jun In‐Kook , Koh Young‐Hag , Song Ju‐Ha , Kim Hyoun‐Ee
Published: April 2006

A novel porous ceramic with a structure containing two three‐dimensional (3D) pore channels in a tetragonal zirconia polycrystals (TZP) ceramic was fabricated using a combination of a CNC‐machining method and slurry coating process. A graphite scaffold with a single interconnected 3D channel as a template was prepared using CNC machining and lamination. The surfaces of the graphite scaffold were then coated uniformly with the TZP slurry, followed by heat treatment at 900°C for 3 h in air to remove the graphite material completely via thermal oxidation and at 1400°C for 3 h in air to sinter the TZP walls. This process produced a dual‐channeled TZP scaffold with an additional 3D channel, which replicated the 3D graphite structure with the pre‐existing channel. The fabricated scaffold showed ultra‐high porosity (91%), high surface area, and high compressive strength (2.04 MPa), as well as a tightly controlled pore structure.
Synthesis, Characterization, and Microwave Dielectric Properties of ATiO3 (A=Co, Mn, Ni) Ceramics
Authors: Anjana Prabhakaran Sreekumari , Sebastian Mailadil Thomas
Published: April 2006

The ATiO3 (A=Co, Mn, Ni) dielectric ceramics have been synthesized by the conventional solid‐state ceramic route. The structure and microstructure of these ceramic samples have been studied using powder X‐ray diffraction and scanning electron microscopy. The microwave dielectric properties such as relative permittivity (ɛr), quality factor (Qu×f), and coefficient of temperature variation of resonant frequency (τf) of the ceramics have been measured in the frequency range 4–6 GHz using resonance methods. The dielectric constant of ATiO3 (A=Co, Mn, Ni) varies from 19 to 25 and τf close to −50 ppm/°C. The ceramics have high‐quality factors (Qu×f) of 62 500 GHz (at 5.42 GHz) for CoTiO3, 15 200 GHz (at 5.22 GHz) for MnTiO3, and 13 900 GHz (at 5.24 GHz) for NiTiO3, respectively.
Analysis of Artificial Radiocarbon in Different Skeletal and Dental Tissue Types to Evaluate Date of Death
Authors: Ubelaker Douglas H. , Buchholz Bruce A. , Stewart John E. B.
Published: April 2006

ABSTRACT: Radiocarbon dating, with special reference to the modern bomb‐curve, can provide useful information to elucidate the date of death of skeletonized human remains. Interpretation can be enhanced with analysis of different types of tissues within a single skeleton because of the known variability of formation times and remodeling rates. Analysis of radiocarbon content of teeth, especially the enamel in tooth crowns, provides information about the date of formation in the childhood years and in consideration of the known timing of tooth formation can be used to estimate the birth date after 1950 ad. Radiocarbon analysis of modern cortical and trabecular bone samples from the same skeleton may allow proper placement on the pre‐1963 or post‐1963 sides of the bomb‐curve as most trabecular bone generally undergoes more rapid remodeling than does most cortical bone. Pre‐1963 bone formation would produce higher radiocarbon values for most trabecular bone than for most cortical bone. This relationship is reversed for formation after 1963. Radiocarbon analysis was conducted in this study on dental, cortical, and trabecular bone samples from two adult individuals of known birth (1925 and 1926) and death dates (1995 and 1959). As expected, the dental results correspond to prebomb‐curve values reflecting conditions during the childhoods of the individuals. The radiocarbon content of most bone samples reflected the higher modern bomb‐curve values. Within the bone sample analyses, the values of the trabecular bone were higher than those of cortical bone and supported the known placement on the pre‐1963 side of the bomb‐curve.
Sequential Monitoring of Burials Containing Large Pig Cadavers Using Ground‐Penetrating Radar
Authors: Schultz John J. , Collins Mary E. , Falsetti Anthony B.
Published: April 2006

ABSTRACT: Ground‐penetrating radar (GPR) was used to monitor 12 pig burials in Florida, each of which contained a large pig cadaver. Six of the cadavers were buried in sand at a depth of 0.50–0.60 m, and the other six were buried at a depth of 1.00–1.10 m and were in contact with the upper surface of a clay horizon. Control excavations with no pig internment were also constructed as blank graves and monitored with GPR. The burials were monitored with GPR for durations of either 12–13 or 21–21.5 months when they were then excavated to correlate the decomposition state of the cadaver with the GPR imagery. Overall, cadavers in sand were easily detected for the duration of this study at 21.5 months, even when completely skeletonized. Conversely, in clay it became increasingly difficult to image the pig cadavers over the first year of burial, even when they still retained extensive soft tissue structures.
Who has two jobs and why? Evidence from rural coastal communities in west Scotland
Authors: Dickey Heather , Theodossiou Ioannis
Published: April 2006

This article examines the incidence of and reasons for multiple‐job holding in the context of rural communities where multiple‐job holding is viewed as an important means of promoting community sustainability. Drawing upon a unique data set of a relatively homogeneous population living in an isolated area on the west coast of Scotland, where employment opportunities are limited, dual‐job holding is investigated within the fisheries and aquaculture occupations. Evidence is found that the hours constraints motive for multiple‐job holding better explains multiple‐job‐holding behavior among employed rural workers in aquaculture than among self‐employed fishermen, and that educational attainment has a positive impact on the incidence of multiple‐job holding.
Intermittent and rhythmic exposure to melatonin in primary cultured adipocytes enhances the insulin and dexamethasone effects on leptin expression
Authors: Alonso‐Vale Maria Isabel Cardoso , Andreotti Sandra , Borges‐Silva Cristina das Neves , Mukai Paula Yuri , Cipolla‐Neto José , Lima Fabio Bessa
Published: April 2006

Abstract:  Considering the cyclic characteristic of production and secretion of pineal melatonin, it is reasonable to assume that this oscillation might be important in determining the variety of its circadian and seasonal effects. To simulate this physiological condition in vitro, isolated adipocytes were exposed to melatonin in a circadian‐like pattern by adding the hormone to the incubating medium during 12 hr (mimicking the night), followed by an equal period without melatonin (mimicking the day). This intermittent procedure was interrupted when three cycles with melatonin were fulfilled (60‐hr incubation). Here, we report the effects of melatonin (1 nM) added intermittently or continuously to the incubating medium alone or in combination with insulin (5 nM) and/or dexamethasone (7 nM) on leptin release and expression by rat adipocytes. After acute 12‐hr incubation neither melatonin nor insulin alone affected leptin expression, but together they increased it by 105%. Dexamethasone increased leptin mRNA content and release (70%) but this effect was not enhanced by melatonin. Nevertheless, after 60 hr under intermittent melatonin, we observed a synergism between melatonin and dexamethasone. This interaction promoted an increment (75% compared with dexamethasone alone) in leptin release and expression. Our results suggest that circadian‐like exposure to melatonin potentiates the dexamethasone action and is important to the effects promoted by insulin on leptin expression. Based on an in vitro approach, this work helps to clarify the physiological relevance and the repercussions of the in vivo circadian pattern of melatonin secretion.
Eye on Washington
Authors: Raphel Sally
Published: April 2006

The Institute of Medicine (IOM) released the latest in the Quality Chasm Series.
Integrating Nursing Care into Systems of Care for Children with Emotional and Behavioral Disorders
Authors: Evans Mary E.
Published: April 2006

PROBLEM:  Recent developments in providing care to children with emotional and behavioral disorders, especially those with serious emotional disturbance, have included the establishment of systems of care. Guided by a set of principles and values, these systems of care have organized and delivered services to children and families with complex needs. To date, nurses have not had a salient role in systems of care.

RESULTS:  It is estimated that 20% of American children and adolescents have an emotional or mental disorder. As many as two thirds of these children are not receiving services. Systems of care have been funded to provide services for these children, particularly for the most severely affected. To date, nursing has not had a prominent role in these systems of care.

CONCLUSIONS:  Based on their knowledge, skills, and holistic approach to care, nurses could better integrate nursing care into systems of care. Possible roles as case managers, primary therapists, in‐home interventionists, and in educational programs are suggested.
Peanut (Arachis hypogaea) response to inoculation with Bradyrhizobium sp. in soils of Argentina
Authors: Bogino P. , Banchio E. , Rinaudi L. , Cerioni G. , Bonfiglio C. , Giordano W.
Published: April 2006

Soil bacteria (rhizobia) of the genus Bradyrhizobium form symbiotic relationships with peanut root cells and fix atmospheric nitrogen by converting it to nitrogenous compounds. Inoculation of peanut with rhizobia can enhance the plant’s ability to fix nitrogen from the air and thereby reduce the requirement for nitrogen fertiliser. We evaluated three Bradyrhizobium sp. strains for effect on root nodulation and on pod yield of peanut in Argentina soils, using laboratory and field experiments. Of these, strain C‐145 was the most effective in laboratory studies. In‐furrow inoculation with this strain produced increased nodule number, relative to seed inoculation. However, pod yield was not increased significantly by either type of inoculation. In view of the inconsistent response of peanut to inoculation, we examined the effect of indigenous strains of bradyrhizobia. The high degree of nodulation and nitrogen fixation produced by indigenous rhizobia were sufficient for maximal yield under the field and inoculation conditions used in this study. The data are important for future investigation of alternative inoculant strains and conditions for improving peanut production.
Effects of Geometry on Brush Seal Pressure and Flow Fields—Part I: Front Plate Configurations
Authors: Dogu Yahya , Aksit Mahmut F.
Published: April 2006

Pressure and flow fields lay at the basis of such common phenomena affecting brush seal performance as bristle flutter, blow-down, hang-up, hysteresis, pressure stiffening, wear, and leakage. Over the past two decades of brush seal evolution, manufacturers and researchers have applied many geometric configurations to the front and backing plates of a standard brush seal in order to control the flow field and consequent seal performance. The number of studies evaluating the effect of geometric configurations on the brush seal flow field remains limited in spite of the high number of filed patent disclosures. This study presents a numerical analysis of brush seal pressure and flow fields with regard to common conceptual front plate configurations. A CFD model has been employed to calculate pressure and flow fields in the seal domain. The model incorporates a bulk porous medium approach for the bristle pack. The effectiveness of various conceptual geometries has been outlined in terms of flow field formation. Results disclose unique effects of geometry on pressure and flow fields such that a longer front plate drives outward radial flow while playing a protective role against upstream cavity disturbances. Findings also indicate that variations in front plate geometry do not directly affect leakage performance. A long front plate or damper shim considerably changes the flow field while at the same time having limited effect on the pressure field. Moreover, a strong suction towards the clearance enhances inward radial flow in clearance operation.
An Empirical Prediction Method for Secondary Losses in Turbines—Part I: A New Loss Breakdown Scheme and Penetration Depth Correlation
Authors: Benner M. W. , Sjolander S. A. , Moustapha S. H.
Published: April 2006

Despite its wide use in meanline analyses, the conventional loss breakdown scheme is based on a number of assumptions that are known to be physically unsatisfactory. One of these assumptions states that the loss generated in the airfoil surface boundary layers is uniform across the span. The loss results at high positive incidence presented in a previous paper (Benner, M. W., Sjolander, S. A., and Moustapha, S. H., 2004, ASME Paper No. GT2004-53786.) indicate that this assumption causes the conventional scheme to produce erroneous values of the secondary loss component. A new empirical prediction method for secondary losses in turbines has been developed, and it is based on a new loss breakdown scheme. In the first part of this two-part paper, the new loss breakdown scheme is presented. Using data from the current authors’ off-design cascade loss measurements, it is shown that the secondary losses obtained with the new scheme produce a trend with incidence that is physically more reasonable. Unlike the conventional loss breakdown scheme, the new scheme requires a correlation for the spanwise penetration depth of the passage vortex separation line at the trailing edge. One such correlation exists (Sharma, O. P., and Butler, T. L., 1987, ASME J. Turbomach., 109, pp. 229–236.); however, it was based on a small database. An improved correlation for penetration distance has been developed from a considerably larger database, and it is detailed in this paper.
Comment on "Phylogenetic MCMC Algorithms Are Misleading on Mixtures of Trees"
Authors: Ronquist Fredrik , Larget Bret , Huelsenbeck John P. , Kadane Joseph B. , Simon Donald , van der Mark Paul
Published: April 2006

Mossel and Vigoda (Reports, 30 September 2005, p. 2207) show that nearest neighbor interchange transitions, commonly used in phylogenetic Markov chain Monte Carlo (MCMC) algorithms, perform poorly on mixtures of dissimilar trees. However, the conditions leading to their results are artificial. Standard MCMC convergence diagnostics would detect the problem in real data, and correction of the model misspecification would solve it.
The incidence and distribution of stress fractures in elite tennis players
Authors: Maquirriain J , Ghisi J P
Published: April 2006

Background:Modern professional tennis involves powerful movements repeatedly subjecting the musculoskeletal system to heavy mechanical load. Thus tennis players are exposed to high risk of overuse injuries including stress fractures.

Objective:To determine the incidence and distribution of stress fractures in elite tennis players.

Study design:Retrospective cohort study.

Methods:The cohort study population consisted of 139 elite players (mean (SD) age, 20.0 (5.0) years; 48 female, 91 male). Stress fractures were identified and confirmed radiologically from medical records during a two year period. Injuries were analysed according to age, sex, site, severity, delay in diagnosis, and time needed to return to sports.

Results:15 players sustained 18 stress fractures, corresponding to an overall case incidence of 12.9% (95% confidence interval (CI), 8.1 to 20.0). The tarsal navicular was most affected (n = 5; 27%), followed by the pars interarticularis (n = 3; 16%), the metatarsals (n = 3; 16%), the tibia (n = 2; 11%) and the lunate (n = 2; 11%). Magnetic resonance imaging showed a greater incidence of “high grade” lesions (94.4%). Stress fracture incidence was significantly higher in juniors (20.3% (95% CI, 11.4 to 33.2)) than in professional players (7.5% (2.8 to 15.6)) (p = 0.045).

Conclusions:There was a high absolute risk (12.9%) of stress fractures in elite tennis players over a two year period. Junior players were at highest risk. The lesions are a major cause of disruption both of training and of competition. Risk factors should therefore be identified and prevention emphasised.
POLYGONAL APPROXIMATION AND ENERGY OF SMOOTH KNOTS
Authors: RAWDON ERIC J. , SIMON JONATHAN K.
Published: April 2006

We establish a fundamental connection between smooth and polygonal knot energies, showing that the Minimum Distance Energy for polygons inscribed in a smooth knot converges to the Möbius Energy of the smooth knot as the polygons converge to the smooth knot. For this to work, the polygons must converge in a "nice" way, and the energies must be correctly regularized. We determine an explicit error bound for the convergence.
TWISTED VERTEX OPERATORS AND BERNOULLI POLYNOMIALS
Authors: DOYON B. , LEPOWSKY J. , MILAS A.
Published: April 2006

Using general principles in the theory of vertex operator algebras and their twisted modules, we obtain a bosonic, twisted construction of a certain central extension of a Lie algebra of differential operators on the circle, for an arbitrary twisting automorphism. The construction involves the Bernoulli polynomials in a fundamental way. We develop new identities and principles in the theory of vertex operator algebras and their twisted modules, and explain the construction by applying general results, including an identity that we call modified weak associativity, to the Heisenberg vertex operator algebra. This paper gives proofs and further explanations of results announced earlier. It is a generalization to twisted vertex operators of work announced by the second author some time ago, and includes as a special case the proof of the main results of that work.
Changes in body temperatures in king penguins at sea: the result of fine adjustments in peripheral heat loss?
Authors: Schmidt Alexander , Alard Frank , Handrich Yves
Published: April 2006

To investigate thermoregulatory adjustments at sea, body temperatures (the pectoral muscle and the brood patch) and diving behavior were monitored during a foraging trip of several days at sea in six breeding king penguins Aptenodytes patagonicus. During inactive phases at sea (water temperature: 4–7°C), all tissues measured were maintained at normothermic temperatures. The brood patch temperature was maintained at the same values as those measured when brooding on shore (38°C). This high temperature difference causes a significant loss of heat. We hypothesize that high-energy expenditure associated with elevated peripheral temperature when resting at sea is the thermoregulatory cost that a postabsorptive penguin has to face for the restoration of its subcutaneous body fat. During diving, mean pectoral temperature was 37.6 ± 1.6°C. While being almost normothermic on average, the temperature of the pectoral muscle was still significantly lower than during inactivity in five out of the six birds and underwent temperature drops of up to 5.5°C. Mean brood patch temperature was 29.6 ± 2.5°C during diving, and temperature decreases of up to 21.6°C were recorded. Interestingly, we observed episodes of brood patch warming during the descent to depth, suggesting that, in some cases, king penguins may perform active thermolysis using the brood patch. It is hypothesized that functional pectoral temperature may be regulated through peripheral adjustments in blood perfusion. These two paradoxical features, i.e., lower temperature of deep tissues during activity and normothermic peripheral tissues while inactive, may highlight the key to the energetics of this diving endotherm while foraging at sea.
Differences in the Appetite-Stimulating Effect of Orexin, Neuropeptide Y and Ghrelin among Young, Adult and Old Rats
Authors: Akimoto-Takano Saeko , Sakurai Chihiro , Kanai Setsuko , Hosoya Hiroko , Ohta Minoru , Miyasaka Kyoko
Published: April 2006

Aging is associated with a progressive decrease in appetite and food intake. The appetite-stimulating peptides orexin A, neuropeptide Y (NPY) and ghrelin are known to play a critical role in food intake. In this study, the stimulatory effect of intracerebroventricular administration of these peptides on food intake was compared among young (4 months old), adult (11 months old) and old (24–27 months old) male Wistar rats. A stainless steel cannula was implanted stereotactically into the left lateral ventricle. After a 7-day recovery period, different doses of orexin A (0.25–3 nmol), NPY and ghrelin (0.03–1 nmol) were injected into the left lateral ventricle without anesthesia. Food consumption was measured at 1, 2 and 4 h after injection. We also examined the plasma levels of acylated and desacyl ghrelin in young and old rats by ELISA. Intracerebroventricular administration of orexin A and NPY stimulated food intake in young and adult rats, but no effects were observed at any dose in old rats. Ghrelin increased food intake in a dose-dependent manner in all groups, and the effect of ghrelin was reduced with advancing age. Neither the acylated nor the desacyl plasma ghrelin level differed significantly between young and old rats. In conclusion, the orexigenic effect of the peptides orexin A, NPY and ghrelin decreased in old rats, and this reduction may have been responsible for the age-related decrease in food intake.
Surgery for Obesity: Panacea or Pandora’s Box?
Authors: Pannala Rahul , Kidd Mark , Modlin Irvin M.
Published: April 2006

Background: Given the increasing prevalence of obesity, healthcare providers should be cognizant of various non-operative (diet, exercise, behavior therapy, and medications) and operative obesity treatments. This review critically evaluates these treatments, especially bariatric surgeries. Methods: Medline analyses using a combination of the following terms: obesity, bariatric surgery, and outcomes were performed with particular emphasis on prospective studies and randomized trials. Results: Non-operative treatments result in modest sustained weight loss (5–8%) at one year. Surgery is recommended for those with BMI >40 or >35 with comorbidities. Laparoscopic adjustable gastric banding, a restrictive procedure, causes 35–54% excess weight loss (EWL) at 1 year. Malabsorptive procedures (biliopancreatic diversions with and without duodenal switch) induce 72–77% EWL but are only performed at few centers. Roux-en-Y gastric bypass, acting through a combination of restriction and malabsorption, results in 69% EWL at 1 year and 49% at 14 years. Each procedure is associated with unique anatomic and nutritional complications. Overall, operative treatment improves comorbidities and may improve all-cause mortality. Conclusions: Surgery is an effective long-term treatment for selected obese patients who have failed other treatments. Further research is needed on prospective comparisons of procedures, evaluation of long-term outcomes, especially between centers and increasingly unrealistic patient expectations.
Local Heat Shock Priming Promotes Recanalization of Thromboembolized Microvasculature by Upregulation of Plasminogen Activators
Authors: Rücker Martin , Schäfer Thilo , Scheuer Claudia , Harder Yves , Vollmar Brigitte , Menger Michael D.
Published: April 2006

Objective—

Thromboembolization and subsequent microvascular perfusion failure is implicated in the pathology of a variety of diseases, including transient ischemic attack (TIA), stroke, and myocardial infarction, and also for the complications after interventional and microsurgical procedures in coronary heart disease and peripheral arterial occlusive disease. In vitro heat shock priming has been suggested to induce plasminogen activators, which are the major upregulators of the fibrinolytic system. Herein, we determined whether local heat shock priming endogenously upregulates plasminogen activators also in vivo, and whether this promotes recanalization of thromboembolized microvasculature.

Methods and Results—

To induce thromboembolization, a suspension of preformed microthrombi (maximum diameter: 40 μm) was injected via the femoral artery into the left hindlimbs of anesthetized rats. Local heat shock priming (42.5°C, 30 minutes) was performed 24 hours before embolization and resulted in a significant increase of endothelium-derived plasminogen activator expression. The study of the microcirculation by intravital microscopy revealed in all tissues analyzed (muscle, periosteum, subcutis, and skin) that heat shock priming significantly (
P
<0.05) accelerates recanalization of the thromboembolized microvasculature when compared with nonprimed and sham-primed controls. Importantly, the addition of plasminogen activator inhibitor-1 to the microthrombi suspension completely blunted the heat shock-induced acceleration of microvascular recanalization.

Conclusions—

Heat shock induces endogenous hyperfibrinolysis by upregulation of plasminogen activators that promote recanalization of thromboembolized microvasculature.
Epidemiological characterization of Plasmodium falciparum in the Republic of Cabo Verde: implications for potential large-scale re-emergence of malaria
Authors: Alves Joana , Roque Ana Luísa , Cravo Pedro , Valdez Tomás , Jelinek Tomas , do Rosário Virgílio E , Arez Ana Paula
Published: April 2006

Background

Malaria has come near eradication at archipelago of Cabo Verde in 1970. Infections are now only observed in Santiago, where outbreaks occur. In these islands, malaria is considered by the international community as being of limited risk and, therefore, no prophylaxis is recommended. Since the understanding of factors that determine malaria outbreaks are crucial for controlling the disease, the present study aimed to investigate if the malaria infections observed in Santiago Island are maintained in isolated foci and in asymptomatic individuals.

Methods

The occurrence of asymptomatic carriers in villages with history of malaria as well as the level of exposure of these populations were investigated using PCR and serological analyses.

Results

Results indicate that malaria is maintained as asymptomatic and sub-patent infections and that the majority of the circulating parasite populations harbour chloroquine-resistant mutations.

Conclusion

These observations highlight the alarming prospect of malaria to become a serious public health problem and underscore the need for a tighter surveillance.
Mining the Mouse Transcriptome of Receptive Endometrium Reveals Distinct Molecular Signatures for the Luminal and Glandular Epithelium
Authors: Niklaus Andrea L. , Pollard Jeffrey W.
Published: April 2006

Epithelia coat most tissues where they sense and respond to the environment and participate in innate immune responses. In the adult mouse uterus, columnar epithelium lines the central lumen and the glands that penetrate the underlying stroma. A nidatory surge of estrogen causes differentiation of the luminal epithelium to the receptive state that permits blastocyst attachment and allows subsequent implantation. Here, using laser-capture microdissection to isolate the luminal and glandular epithelia separately, we have profiled gene expression 2 h before embryo attachment to determine whether there are unique roles for these two epithelial structures in this process. Although most genes were expressed in both compartments, there was greater expression of 153 and 118 genes in the lumen and glands, respectively. In the luminal epithelium, there is enrichment in lipid, metal-ion binding, and carbohydrate-metabolizing enzymes, whereas in the glands, immune response genes are emphasized. In situ hybridization to uterine sections obtained from mice during the preimplantation period validated these data and indicated an array of previously undocumented genes expressed with unique patterns in these epithelia. The data show that each epithelial compartment has a distinct molecular signature and that they act differentially and synergistically to permit blastocyst implantation.
Quantitative Reverse Transcription-PCR Assay for Detection of mRNA Encoding Full-Length Human Tissue Kallikrein 7: Prognostic Relevance of KLK7 mRNA Expression in Breast Cancer 3
Authors: Holzscheiter Leon , Biermann Julia C , Kotzsch Matthias , Prezas Panagiotis , Farthmann Juliane , Baretton Gustavo , Luther Thomas , Tjan-Heijnen Vivianne CG , Talieri Maroulio , Schmitt Manfred , Sweep Fred CGJ , Span Paul N , Magdolen Viktor
Published: April 2006

Background: The human tissue kallikrein gene family (KLK1 to KLK15) encodes a group of 15 serine proteases (hK1 to hK15), several of which have been implicated in cancer-related processes.

Methods: We established a specific quantitative reverse transcription-PCR assay for full-length KLK7 mRNA that excluded amplification of the exon 2 deletion splice variant (the latter does not encode a functional protease), and evaluated full-length KLK7 mRNA expression [normalized to human glucose-6-phosphate dehydrogenase (h-G6PDH)] in tumor tissue specimens from 155 breast cancer patients.

Results: High KLK7 mRNA expression (continuous) was significantly associated with a better patient outcome according to both univariate (P = 0.005) and multivariate (P = 0.046) Cox survival analysis. Separation of patients by optimized dichotomization revealed a significantly better prognosis for patients with high KLK7 mRNA status (n = 89) compared with patients with low KLK7 mRNA status (n = 66) [univariate hazard ratio (HR) = 0.45 (P = 0.001); multivariate HR = 0.50 (P = 0.005)]. In the subgroup of patients not receiving adjuvant treatment (n = 69), KLK7 mRNA status was a significant prognosticator [univariate HR = 0.29 (P = 0.002); multivariate HR = 0.40 (P = 0.034)]. This subgroup was least influenced by postoperative treatment and thus best showed the impact of KLK7 expression on the natural course of breast cancer disease.

Conclusion: Expression of full-length KLK7 mRNA may represent a new prognostic marker in breast cancer disease.
Heinrich Isaac among the Florentines
Authors: WILSON BLAKE
Published: April 2006

In the archives of the old and wealthy patrician family of the “da Filicaia” housed in the Florentine Archivio di Stato survives a group of letters written by, among others, one Ambrogio Angeni to the young Antonio da Filicaia, away on family business in northern Europe for extended periods of time during the 1480s and 1490s. The correspondence details the musical activities of these young men's Florentine brigata and reveals a close involvement with Heinrich Isaac and proximity to Lorenzo de' Medici's private musical circles. The letters document a very active traffic in musical scores, both vernacular works composed in Florence by Isaac and others that were mailed north, as well as sacred and secular works composed in France and sent to Florence. More specifically, the letters contain many musical references to new compositions, works by Isaac, preparations for carnival, aesthetic judgments and technical discussions, Lorenzo's patronage, and a very active local composer previously unknown to musicologists. The correspondence dates from 1487–89, while Antonio was residing in Nantes (Brittany), and it provides an unprecedented view of musical life in Florence at a critical period when carnival celebrations were resurgent, northern repertory was being collected and copied, northern composers (like Isaac) were interacting with local composers, and compositional procedures were changing.
Performing for Strangers: Women, Dance, and Music in Quattrocento Florence*
Authors: Bryce Judith
Published: April 2006

Contrary to a tradition of scholarly insistence on the invisibility of Florentine patrician women outside the domestic sphere, it can be argued such women did in effect perform a significant, public, or quasi-public, function in the negotiation of relationships between the Republic and other Italian, and European, elites. This article assembles fragmentary evidence concerning dancing and musical performance by women directed towards the entertainment of visiting notables in the second half of the Quattrocento, and uses modern concepts of gendered performance and the performance of gender to speculate on the nature of that experience for the women involved.
Healing the Body Politic: French Royal Doctors, History, and the Birth of a Nation 1560-1634
Authors: Soll Jacob
Published: April 2006

This article examines the role played by royal doctors in forming an empirical political science in France at the end of the sixteenth century. Bringing with them took from the Galenic tradition, doctors such as Rodolphe Le Maistre, Abraham-Nicolas de La Framboisière, and Jean Héroard doubled as political counselors. They not only looked for ways to heal the king's body, they also looked for ways to heal and regulate the body of the nation. Their new vision of the monarch as a practicing physician of the state is an essential yet unknown facet of the origins of political modernity.
Nuns, Images, and the Ideals of Women's Monasticism: Two Paintings from the Cistercian Convent of Flines*
Authors: Pearson Andrea G.
Published: April 2006

This study explores the dynamics between visual images and expectations for feminine monasticism in northern Europe via two paintings from the Cistercian convent of Flines. It argues that abbess Jeanne de Boubais commissioned the images for clerics who had promoted reform of Flines, in order to suggest compliance with the mandates of the program and the integral place of the convent within Cistercian monasticism. In the wake of the dissolution of several convents that had resisted reform, conveying a desire to yield to the Order must have seemed crucial for the community's survival.