bluuebunny/crossref_metadata_2025 huggingface dataset:
Validation of a maternal questionnaire on correlates of physical activity in preschool children
Authors: McMinn Alison M , van Sluijs Esther MF , Harvey Nicholas C , Cooper Cyrus , Inskip Hazel M , Godfrey Keith M , Griffin Simon J
Published: December 2009

Background

Valid measures of physical activity correlates in preschool children are lacking. This study aimed to assess the validity, factor structure and internal consistency of a maternal questionnaire on potential correlates of four-year-old children's physical activity.

Methods

The questionnaire was designed to measure the following constructs: child personal factors; parental support and self-efficacy for providing support; parental rules and restrictions; maternal attitudes and perceptions; maternal behaviour; barriers to physical activity; and the home and local environments. Two separate studies were conducted. Study I included 24 mothers of four-year-old children who completed the questionnaire then participated in a telephone interview covering similar items to the questionnaire. To assess validity, the agreement between interview and questionnaire responses was assessed using Cohen's kappa and percentage agreement. Study II involved 398 mothers of four-year-old children participating in the Southampton Women's Survey. In this study, principal components analysis was used to explore the factor structure of the questionnaire to aid future analyses with these data. The internal consistency of the factors identified was assessed using Cronbach's alpha.

Results

Kappa scores showed 30% of items to have moderate agreement or above, 23% to have fair agreement and 47% to have slight or poor agreement. However, 89% of items had fair agreement as assessed by percentage agreement (≥ 66%). Limited variation in responses to variables is likely to have contributed to some of the low kappa values. Six questions had a low kappa and low percentage agreement (defined as poor validity); these included questions from the child personal factors, maternal self-efficacy, rules and restrictions, and local environment domains. The principal components analysis identified eleven factors and found several variables to stand alone. Eight of the composite factors identified had acceptable internal consistency (α ≥ 0.60) and three fell just short of achieving this (0.60 > α > 0.50).

Conclusion

Overall, this maternal questionnaire had reasonable validity and internal consistency for assessing potential correlates of physical activity in young children. With minor revision, this could be a useful tool for future research in this area. This, in turn, will aid the development of interventions to promote physical activity in this age group.
Increasing phylogenetic resolution at low taxonomic levels using massively parallel sequencing of chloroplast genomes
Authors: Parks Matthew , Cronn Richard , Liston Aaron
Published: December 2009

Background

Molecular evolutionary studies share the common goal of elucidating historical relationships, and the common challenge of adequately sampling taxa and characters. Particularly at low taxonomic levels, recent divergence, rapid radiations, and conservative genome evolution yield limited sequence variation, and dense taxon sampling is often desirable. Recent advances in massively parallel sequencing make it possible to rapidly obtain large amounts of sequence data, and multiplexing makes extensive sampling of megabase sequences feasible. Is it possible to efficiently apply massively parallel sequencing to increase phylogenetic resolution at low taxonomic levels?

Results

We reconstruct the infrageneric phylogeny of Pinus from 37 nearly-complete chloroplast genomes (average 109 kilobases each of an approximately 120 kilobase genome) generated using multiplexed massively parallel sequencing. 30/33 ingroup nodes resolved with ≥ 95% bootstrap support; this is a substantial improvement relative to prior studies, and shows massively parallel sequencing-based strategies can produce sufficient high quality sequence to reach support levels originally proposed for the phylogenetic bootstrap. Resampling simulations show that at least the entire plastome is necessary to fully resolve Pinus, particularly in rapidly radiating clades. Meta-analysis of 99 published infrageneric phylogenies shows that whole plastome analysis should provide similar gains across a range of plant genera. A disproportionate amount of phylogenetic information resides in two loci (ycf1, ycf2), highlighting their unusual evolutionary properties.

Conclusion

Plastome sequencing is now an efficient option for increasing phylogenetic resolution at lower taxonomic levels in plant phylogenetic and population genetic analyses. With continuing improvements in sequencing capacity, the strategies herein should revolutionize efforts requiring dense taxon and character sampling, such as phylogeographic analyses and species-level DNA barcoding.
Development of a synoptic MRI report for primary rectal cancer
Authors: Spiegle Gillian , Leon-Carlyle Marisa , Schmocker Selina , Fruitman Mark , Milot Laurent , Gagliardi Anna R , Smith Andy J , McLeod Robin S , Kennedy Erin D
Published: December 2009

Background

Although magnetic resonance imaging (MRI) is an important imaging modality for pre-operative staging and surgical planning of rectal cancer, to date there has been little investigation on the completeness and overall quality of MRI reports. This is important because optimal patient care depends on the quality of the MRI report and clear communication of these reports to treating physicians. Previous work has shown that the use of synoptic pathology reports improves the quality of pathology reports and communication between physicians.

Methods

The aims of this project are to develop a synoptic MRI report for rectal cancer and determine the enablers and barriers toward the implementation of a synoptic MRI report for rectal cancer in the clinical setting. A three-step Delphi process with an expert panel will extract the key criteria for the MRI report to guide pre-operative chemoradiation and surgical planning following a review of the literature, and a synoptic template will be developed. Furthermore, standardized qualitative research methods will be used to conduct interviews with radiologists to determine the enablers and barriers to the implementation and sustainability of the synoptic MRI report in the clinic setting.

Conclusion

Synoptic MRI reports for rectal cancer are currently not used in North America and may improve the overall quality of MRI report and communication between physicians. This may, in turn, lead to improved patient care and outcomes for rectal cancer patients.
Abdominal angina due to recurrence of cancer of the papilla of Vater: a case report
Authors: Biolato Marco , Gabrieli Maria Letizia , Parente Antonello , Racco Simona , Costantini Melania , Bonomo Lorenzo , Rapaccini Gian Ludovico , Gasbarrini Giovanni , Grieco Antonio
Published: December 2009

Introduction

Abdominal angina is usually caused by atherosclerotic disease, and other causes are considered uncommon. This is the first report of a case of abdominal angina secondary to neoplastic vascular stenosis caused by local recurrence of an adenocarcinoma of the papilla of Vater.

Case presentation

An 80-year-old woman of Caucasian origin presented with abdominal pain and diarrhea. She had undergone a pancreaticoduodenectomy for adenocarcinoma of the papilla of Vater four years earlier. Computed tomography revealed a mass surrounding her celiac trunk and superior mesenteric artery. Her abdominal pain responded poorly to analgesic drugs, but disappeared when oral feedings were withheld. A duplex ultrasonography of the patient's splanchnic vessels was consistent with vascular stenosis. Parenteral nutrition was started and the patient remained pain free until her death.

Conclusion

Pain relief is an important therapeutic target in patients with cancer. In this case, abdominal pain was successfully managed only after the ischemic cause had been identified. The conventional analgesic therapy algorithm based on nonsteroidal anti-inflammatory drugs and opioids had been costly and pointless, whereas the simple withdrawal of oral feeding spared the patient of the discomfort of additional invasive procedures and allowed her to spend her remaining days in a completely pain-free state.
Core promoter acetylation is not required for high transcription from the phosphoenolpyruvate carboxylase promoter in maize
Authors: Horst Ina , Offermann Sascha , Dreesen Bjoern , Niessen Markus , Peterhansel Christoph
Published: December 2009

Background

Acetylation of promoter nucleosomes is tightly correlated and mechanistically linked to gene activity. However, transcription is not necessary for promoter acetylation. It seems, therefore, that external and endogenous stimuli control histone acetylation and by this contribute to gene regulation. Photosynthetic genes in plants are excellent models with which to study the connection between stimuli and chromatin modifications because these genes are strongly expressed and regulated by multiple stimuli that are easily manipulated. We have previously shown that acetylation of specific histone lysine residues on the photosynthetic phosphoenolpyruvate carboxylase (Pepc) promoter in maize is controlled by light and is independent of other stimuli or gene activity. Acetylation of upstream promoter regions responds to a set of other stimuli which include the nutrient availability of the plant. Here, we have extended these studies by analysing histone acetylation during the diurnal and circadian rhythm of the plant.

Results

We show that histone acetylation of individual lysine residues is removed from the core promoter before the end of the illumination period which is an indication that light is not the only factor influencing core promoter acetylation. Deacetylation is accompanied by a decrease in gene activity. Pharmacological inhibition of histone deacetylation is not sufficient to prevent transcriptional repression, indicating that deacetylation is not controlling diurnal gene regulation. Variation of thePepcpromoter activity during the day is controlled by the circadian oscillator as it is maintained under constant illumination for at least 3 days. During this period, light-induced changes in histone acetylation are completely removed from the core promoter, although the light stimulus is continuously applied. However, acetylation of most sites on upstream promoter elements follows the circadian rhythm.

Conclusion

Our results suggest a central role of upstream promoter acetylation in the quantitative regulation of gene expression in this model gene. Induced core promoter acetylation is dispensable for the highest gene expression in the diurnal and circadian rhythm.
Repressive and non-repressive chromatin at native telomeres in Saccharomyces cerevisiae
Authors: Loney Esther R , Inglis Peter W , Sharp Sarah , Pryde Fiona E , Kent Nicholas A , Mellor Jane , Louis Edward J
Published: December 2009

Background

In Saccharomyces cerevisiae genes that are located close to a telomere can become transcriptionally repressed by an epigenetic process known as telomere position effect. There is large variation in the level of the telomere position effect among telomeres, with many native ends exhibiting little repression.

Results

Chromatin analysis, using microccocal nuclease and indirect end labelling, reveals distinct patterns for ends with different silencing states. Differences were observed in the promoter accessibility of a subtelomeric reporter gene and a characteristic array of phased nucleosomes was observed on the centromere proximal side of core X at a repressive end. The silent information regulator proteins 2 - 4, the yKu heterodimer and the subtelomeric core X element are all required for the maintenance of the chromatin structure of repressive ends. However, gene deletions of particular histone modification proteins can eliminate the silencing without the disruption of this chromatin structure.

Conclusion

Our data identifies chromatin features that correlate with the silencing state and indicate that an array of phased nucleosomes is not sufficient for full repression.
Pathologic dislocation of the shoulder secondary to septic arthritis: a case report
Authors: Bagheri Farshid , Ebrahimzadeh Mohamad H , Sharifi Seyed Reza , Ahmadzadeh-Chabok Hossien , Khajah-Mozaffari Javad , Fattahi Asieh S
Published: December 2009

Septic arthritis of the shoulder is uncommon in adults, and complete dislocation of the glenohumeral joint following septic arthritis is extremely rare. We report a case of pathologic shoulder dislocation secondary to septic arthritis in an intravenous drug abuser.
Closed total talus dislocation without fracture: a case report
Authors: Sharifi Seyed Reza , Ebrahimzadeh Mohamad H , Ahmadzadeh-Chabok Hosein , Khajeh-Mozaffari Javad
Published: December 2009

Total dislocation of the talus from all of its joints is a rare injury specially when the talus and malleoli are not fractured and frequently it is as a result of a high-energy trauma. It usually leads to degenerative changes in neighboring joints and frequently avascular necrosis is a predictable outcome. We present a case of total talus dislocation because of a high-energy trauma in association with other major fractures resulting from a fall from height, but no fracture could be detected in the talus and any of malleols. Closed reduction was unsuccessful and we performed open reduction. At 6 month post operation follow-up, the talus didn't show subluxation and avascular necrosis could not be detected.
The macrophage: the intersection between HIV infection and atherosclerosis
Authors: Crowe Suzanne M , Westhorpe Clare L V , Mukhamedova Nigora , Jaworowski Anthony , Sviridov Dmitri , Bukrinsky Michael
Published: December 2009

Review of the increased risk of coronary artery disease with HIV-1 infection, association with traditional risk factors, monocyte activation, and impaired cholesterol metabolism.

HIV-infected individuals are at increased risk of coronary artery disease (CAD) with underlying mechanisms including chronic immune activation and inflammation secondary to HIV-induced microbial translocation and low-grade endotoxemia; direct effects of HIV and viral proteins on macrophage cholesterol metabolism; and dyslipidemia related to HIV infection and specific antiretroviral therapies. Monocytes are the precursors of the lipid-laden foam cells within the atherosclerotic plaque and produce high levels of proinflammatory cytokines such as IL-6. The minor CD14+/CD16+ “proinflammatory” monocyte subpopulation is preferentially susceptible to HIV infection and may play a critical role in the pathogenesis of HIV-related CAD. In this review, the central role of monocytes/macrophages in HIV-related CAD and the importance of inflammation and cholesterol metabolism are discussed.
Critical Roles of Kisspeptins in Female Puberty and Preovulatory Gonadotropin Surges as Revealed by a Novel Antagonist
Authors: Pineda R. , Garcia-Galiano D. , Roseweir A. , Romero M. , Sanchez-Garrido M. A. , Ruiz-Pino F. , Morgan K. , Pinilla L. , Millar R. P. , Tena-Sempere M.
Published: December 2009

Kisspeptins (Kp) have recently emerged as master regulators of the reproductive axis and among the most potent elicitors of GnRH-gonadotropin secretion. Despite their paramount importance in reproductive physiology and their potential therapeutic implications, development of Kp antagonists has remained elusive, and only recently has the first compound with the ability to block Kp actions in vitro and in vivo, namely p234, been reported. However, previous in vivo studies all used acute central injections, whereas characterization of the effects of the antagonist after continuous or systemic administration, which poses pharmacological challenges, is still pending. We report herein a comprehensive series of analyses on the impact of continuous intracerebroventricular infusion of p234 on puberty onset and the preovulatory surge of gonadotropins in the female rat. In addition, the effects of systemic (ip) administration of a tagged p234-penetratin, with a predicted higher permeability at the blood-brain barrier, on Kp-10 induced gonadotropin secretion were evaluated. Central infusion of p234 to pubertal females delayed vaginal opening and decreased uterine and ovarian weights at the expected time of puberty, without affecting body weight. Likewise, chronic intracerebroventricular administration of p234 for 4 d prevented the preovulatory surges of LH and FSH. In addition, systemic (ip) administration of p234-penetratin significantly attenuated acute LH and FSH responses to Kp-10, either after intracerebroventricular or ip injection of Kp. Our data document the validity of p234 for antagonizing Kp actions in vivo and provide direct experimental evidence for the important role of Kp signaling in the key events of female reproduction, such as puberty onset and the preovulatory surge of gonadotropins.
Palmitate Attenuates Insulin Signaling and Induces Endoplasmic Reticulum Stress and Apoptosis in Hypothalamic Neurons: Rescue of Resistance and Apoptosis through Adenosine 5′ Monophosphate-Activated Protein Kinase Activation
Authors: Mayer Christopher M. , Belsham Denise D.
Published: December 2009

Hypothalamic insulin signaling is essential to the maintenance of glucose and energy homeostasis. During pathological states, such as obesity and type 2 diabetes mellitus, insulin signaling is impaired. One key mechanism involved in the development of insulin resistance is lipotoxicity, through increased circulating saturated fatty acids. Although many studies have begun to determine the underlying mechanisms of lipotoxicity in peripheral tissues, little is known about the effects of excess lipids in the brain. We used a hypothalamic, neuronal cell model, mHypoE-44, to understand how the highly prevalent nonesterified fatty acid, palmitate, affects neuronal insulin signaling. Through Western blot analysis, we discerned that prolonged exposure to palmitate impairs insulin activation, as assessed by phosphorylation of Akt. We investigated the role of endoplasmic reticulum (ER) stress, which is known to promote cellular insulin resistance and apoptosis in peripheral tissues. Palmitate treatment induced ER stress through a c-Jun N-terminal kinase (JNK)-dependent pathway because a selective JNK inhibitor blocked palmitate activation of the ER stress pathways eIF2α and X-box binding protein-1. Interestingly, JNK inhibition did not prevent the palmitate-mediated cleaved caspase-3 increase, an apoptotic marker, or insulin signaling attenuation. However, pretreatment with the AMP kinase activator, aminoimidazole carboxamide ribonucleotide, blocked JNK phosphorylation and importantly prevented caspase-3 cleavage and restored insulin signaling during short-term exposure to palmitate. Thus, activation of AMP kinase prevents the deleterious effects of palmitate on hypothalamic neurons by inhibiting the onset of insulin resistance and apoptosis.
Association of Duoxes with Thyroid Peroxidase and Its Regulation in Thyrocytes
Authors: Song Yue , Ruf Jean , Lothaire Philippe , Dequanter Didier , Andry Guy , Willemse Esther , Dumont Jacques Emile , Van Sande Jacqueline , De Deken Xavier
Published: December 2009

Context: Thyroid hormone synthesis requires H2O2 produced by dual oxidases (Duoxes) and thyroperoxidase (TPO). Defects in this system lead to congenital hypothyroidism. H2O2 damage to the thyrocytes may be a cause of cancer.

Objective: The objective of the study was to investigate whether Duox and TPO, the H2O2 producer and consumer, might constitute a complex in the plasma membrane of human thyroid cells, thus maximizing efficiency and minimizing leakage and damage.

Design: The interaction between Duox and TPO was studied by coimmunoprecipitation and Western blotting of plasma membranes from incubated follicles prepared from freshly resected human thyroid tissue from patients undergoing thyroidectomy, and COS-7 cells transiently transfected with the entire Duoxes or truncated [amino (NH2) or carboxyl (COOH) terminal].

Results: The following results were reached: 1) Duox and TPO from membranes are coprecipitated, 2) this association is up-regulated through the Gq-phospholipase C-Ca2+-protein kinase C pathway and down-regulated through the Gs-cAMP-protein kinase A pathway, 3) H2O2 increases the association of Duox1 and Duox2 to TPO in cells and in membranes, and 4) truncated NH2- or COOH-terminal Duox1 and Duox2 proteins show different binding abilities with TPO.

Conclusion: Coimmunoprecipitations show that Duox and TPO locate closely in the plasma membranes of human thyrocytes, and this association can be modulated by H2O2, optimizing working efficiency and minimizing H2O2 spillage. This association could represent one part of a postulated pluriprotein complex involved in iodination. This suggests that defects in this association could impair thyroid hormone synthesis and lead to thyroid insufficiency and cell damage.
Exquemelin's Buccaneers: Violence, Authority, and the Word in Early Caribbean History
Authors: Frohock Richard
Published: December 2009

First published in Dutch in 1678, Alexander Exquemelin's Buccaneers of America (Americaensche Zee-Rovers) presented European readers with a novel and shockingly candid portrait of the international band of sea rovers operating throughout the Caribbean and along the coastlines of Central and South America in the late seventeenth century. Exquemelin's sensationalized account captured considerable attention and was translated into multiple European languages, including German, Spanish, and English, in the ensuing years. Many scholarly treatments of his influential narrative have focused on distinguishing truth from fiction; sometimes, he has been cited as a reliable witness, and often he has been criticized for his apparent fabrications and exaggerations. This essay proposes an alternative approach to questions of truthfulness by focusing instead on how Exquemelin himself continually engages with issues of language and authority. Exquemelin was fascinated with the challenges of producing credible accounts of experience and with the techniques and politics of manipulating narrative for empowerment. For Exquemelin, buccaneers are not only violent criminals but also linguistic rebels who usurp, but ultimately cannot control, the authoritative word. Exquemelin also examines language produced by officials of empire, such as Spanish priests, English governors, and state sovereigns. Drawing parallels between their deceptive language and that of the buccaneers, Exquemelin indicates that the horror of piracy, which consists of atrocities concealed and advanced through discursive manipulation, is also the horror of imperialism generally.
Laminin deposition in the extracellular matrix: a complex picture emerges
Authors: Hamill Kevin J. , Kligys Kristina , Hopkinson Susan B. , Jones Jonathan C. R.
Published: December 2009

Laminins are structural components of basement membranes. In addition, they are key extracellular-matrix regulators of cell adhesion, migration, differentiation and proliferation. This Commentary focuses on a relatively understudied aspect of laminin biology: how is laminin deposited into the extracellular matrix? This topic has fascinated researchers for some time, particularly considering the diversity of patterns of laminin that can be visualized in the matrix of cultured cells. We discuss current ideas of how laminin matrices are assembled, the role of matrix receptors in this process and how laminin-associated proteins modulate matrix deposition. We speculate on the role of signaling pathways that are involved in laminin-matrix deposition and on how laminin patterns might play an important role in specifying cell behaviors, especially directed migration. We conclude with a description of new developments in the way that laminin deposition is being studied, including the use of tagged laminin subunits that should allow the visualization of laminin-matrix deposition and assembly by living cells.
Characterization of low-impedance materials at elevated strain rates
Authors: Hiermaier S , Meenken T
Published: December 2009

Experimental characterization of materials at elevated strain rates of the order of 103 s×1 is typically performed by Hopkinson-bar-type facilities. The specific nature of Hopkinson bar tests is that a specimen is loaded by waves. As both the input and output bars are often made from high-impedance metallic materials, the ratio between transmitted and reflected wave components is very poor in the case of low-impedance specimen materials such as rubbers and foams. That poor wave transmission brings with it a limited quality of the signal-to-noise ratio. Changing the bar materials (e.g. to polycarbonate) is of little help because of the related viscous effects. A further deficiency of the wave-driven Hopkinson bar test for many rubber and foam applications is the comparably small amount of compression that is achievable. Maximum compressions of 95 per cent and above, often expected for damping and energy absorption applications, are out of the range of most Hopkinson bar set-ups. In order to overcome these deficiencies, first a split Hopkinson pressure bar (SHPB) facility was equipped with polyvinylidenefluoride (PVDF) thin-film sensors. Second, a direct-impact set-up for low-impedance materials was developed and calibrated at the Ernst Mach Institute (EMI). With the PVDF gauges, the range of application both for the SHPB and for the new set-up was enhanced. This is demonstrated with an SHPB-based investigation of stress homogeneity in polyurethane (PU) specimens. The direct-impact facility made it possible to derive the stress–strain relations for PU-rubber up to strain rates in the range of several 103 s×1. Maximum compressions of more than 95 per cent were achieved. The paper describes the limitations of a classic SHPB set-up applied to low-impedance materials. The problem of stress homogeneity is addressed, and a set-up for a new direct-impact facility is presented. As an example application, a Confor-Blue foam, typically used for automotive crash-test dummies, is characterized at strain rates between 160 and 1115 s×1.
Numerical investigation of a centrifugal pump running in reverse mode
Authors: Fernández J , Barrio R , Blanco E , Parrondo J L , Marcos A
Published: December 2009

This article reports a work on the three-dimensional flow simulation in a centrifugal pump operating in reverse mode. The simulations were carried out with the commercial code Fluent using unsteady flow calculations together with a sliding mesh technique. Hence, it was possible to account for the effect of blade—tongue interactions on the local flow. The numerical predictions were compared with the experimentally determined performance characteristics and also with the static pressure distribution obtained around the periphery of the impeller. Once validated, the numerical model was used to investigate the global flow. Additionally, the total radial force (steady and unsteady components) on the impeller for a number of flowrates was estimated. It was found that the unsteady radial force (peak to peak) varied between 24 and 54.3 per cent of the steady value within the considered flow interval. The maximum force amplitude was reached when the trailing edge of one blade (pressure side) was located 3° downstream of the tongue tip.
Numerical investigations of pressure loss and heat transfer in a 180° bend of a ribbed two-pass internal cooling channel with engine-similar cross-sections
Authors: Schüler M , Neumann S O , Weigand B
Published: December 2009

Numerical investigations of a two-pass internal cooling channel with engine representative cross-sections related to turbine blade cooling were conducted. The channel consisted of a trapezoidal leading edge pass, a sharp 180° bend, and a nearly rectangular outlet pass. The numerical predictions were validated against experimental results in terms of pressure distributions, total pressure losses, and local heat transfer coefficient distributions. The investigations focused on the influence of rib turbulators and tip-to-web distance on the pressure loss and heat transfer. The channel was equipped with skewed ribs (α = 45°, P/ e = 10, and e/ dh = 0.1) in a parallel and a staggered configuration. The dimensionless tip-to-web distance Wel/ dS was varied from 0.6 to 2.0. The investigated Reynolds number was 50 000. The computational study was performed by solving the Reynolds-averaged Navier—Stokes equations with the commercial finite-volume-solver FLUENT and three turbulence models: the realizable k—ε turbulence model with a two-layer wall treatment, the k—ω—SST model, and the v2– f model. The computations were performed on hybrid, unstructured grids created with the semi-automatic grid generator CENTAUR.

The predictions using the k—ω—SST model were in overall agreement with the experimental results, showing an increasing pressure loss with a decreasing tip-to-web distance while the heat transfer was increased to a smaller extent.
Foam sclerotherapy techniques: different gases and methods of preparation, catheter versus direct injection
Authors: Cavezzi A , Tessari L
Published: December 2009

Introduction

Foam sclerotherapy has gained a great popularity among phlebologists worldwide, although a major lack of homogeneity in the material used to produce sclerosant foam (SF) and to inject SF has been reported.

Aims

To highlight the literature data and a few personal clinical and experimental outcomes concerning the main variables in SF production and injection.

Methods

A review of the published literature and of our own 12 year clinical and experimental experience has been undertaken in order to focus on a few variables of the material and methods used to produce SF with Tessari method and to inject SF.

Results

In SF production, differences in gas components, liquid to gas ratio, as well in disposable material can variably influence the resulting SF. Similarly SF injection through ultrasound guidance, with needle, or with short/long catheter may exhibit different foam behaviours according to the variable material and techniques which are employed. More recently the introduction of long catheters, possibly together with hook phlebectomy, seems to potentiate the short-mid term outcomes of foam sclerotherapy.

Conclusion

SF formation is greatly influenced by the choice of the gas component, the liquid-to-gas ratio, the type of syringes; also larger needles are to be preferred for injection of SF, while long catheters seem to represent a valid alternative especially when combined with tumescence to minimise saphenous diameter.
Sampling Practices of Internal Auditors at Corporations on the Standard & Poor's Toronto Stock Exchange Composite Index*
Authors: Maingot Michael , Quon Tony K.
Published: December 2009

The purpose of this study is to find out how often statistical and nonstatistical audit sampling practices are used by internal auditors in companies listed on the Standard and Poor's (S&P) Toronto Stock Exchange (TSX) Composite Index and how such practices are related to the training and background of the respondents. We adapted the questionnaire used by Hall, Hunton, and Pierce (2002) in their survey of U.S. auditors in public accounting, industry, and government.

Although 20 percent of companies responding do not have an internal audit department, the other 80 percent use statistical methods to plan sample sizes 15 percent (+5 percent) of the time, random sample selection methods 23 percent (+5 percent) of the time, but statistical evaluation methods only 10% (+4%) of the time. Despite the low percentage use, almost half of the respondents reported substantial training in statistical sampling and evaluation methods. Moreover, we found statistically significantly higher proportions of respondents with substantial training in audit sampling methods among companies cross‐listed on U.S. exchanges compared with companies listed only on the TSX.

Finally, respondents with a chartered accountant designation tend to have a negative impact on the use of statistical methods in audit sampling, and companies cross‐listed on U.S. exchanges tend to have larger internal audit departments than companies listed only on the TSX.
Great Galway Goslings: Organizational Context of Managerial Accounting*
Authors: Abdallah Wagdy , Henry Theresa F. , Murtuza Athar , Weiss Renee E.
Published: December 2009

This case seeks to enhance student understanding of the relationship between accounting information and the order fulfllment and production activities of a manufacturing frm, Great Galway Goslings. Great Galway Goslings manufactures goose sculptures and has been suffering losses in recent years. Students draw on the skills they learned in financial accounting to analyze the company's order fulfllment activities, identify economic transactions, and prepare journal entries. The case provides a link to managerial accounting topics as students use segment financial statements to create contribution margin income statements, perform break‐even analyses, and recommend whether Great Galway Goslings should keep its retail business segment. Students will become familiar with the key features of business process management (BPM) and the extensive, real‐world activities that a manufacturing entity engages in to fll an order. Students will analyze the company's existing order fulfllment process and apply their knowledge of BPM to recommend process improvements for Great Galway. This case contributes to the accounting case literature by serving as a bridge from financial accounting to managerial accounting, intertwining many topics from managerial accounting into one cohesive case, and providing real‐world business process knowledge. Student feedback indicates that, overall, the case met its stated learning objectives. Great Galway Goslings is appropriate for an undergraduate introductory managerial accounting course but can be adapted to the equivalent graduate‐level course or an accounting information systems course.
Progressive Changes in Synaptic Inputs to Motoneurons in Adult Sacral Spinal Cord of a Mouse Model of Amyotrophic Lateral Sclerosis
Authors: Jiang Mingchen , Schuster Jenna E. , Fu Ronggen , Siddique Teepu , Heckman C. J.
Published: December 2009

Amyotrophic lateral sclerosis (ALS) is characterized by progressive degeneration of motoneurons. One potential mechanism is excitotoxicity. We studied the behaviors of spinal neurons using anin vitropreparation of the sacral cord from the G93A SOD1 mouse model of ALS. Measurements were conducted at presymptomatic [approximately postnatal day 50 (∼P50)], early (∼P90), and late (>P120) stages of the disease. Short-latency reflexes (SRs) in ventral roots, presumably monosynaptic, were evoked by electrical stimulation of a dorsal root. The fraction of motoneurons capable of responding to this activation was evaluated by measuring the compound action potential [total motor activity (TMA)] evoked by antidromic stimulation of the distal ventral root. In mutant SOD1 (mSOD1) mice, both the SR and the TMA decreased with age compared with nontransgenic littermates, ruling out the SR as a source of increasing excitotoxicity. Spinal interneuron activity was assessed using the synchronized ventral root bursts generated by both bath application of blockers of inhibitory neurotransmitters (glycine, GABAA) and agonists of glutamate receptors (especially NMDA receptors). After symptom onset, a higher percentage of preparations from mSOD1 mice exhibited bursting, and these bursts exhibited more sub-bursts and a more disorganized pattern. In mSOD1 mice with clear muscle tremor, the ventral roots exhibited spontaneous synchronized bursts, which were highly sensitive to the blockade of NMDA receptors. These data suggest that although short-latency sensory input does not increase as symptoms develop, interneuron activity does increase and may contribute to excitotoxicity.
Damage to Association Fiber Tracts Impairs Recognition of the Facial Expression of Emotion
Authors: Philippi Carissa L. , Mehta Sonya , Grabowski Thomas , Adolphs Ralph , Rudrauf David
Published: December 2009

An array of cortical and subcortical structures have been implicated in the recognition of emotion from facial expressions. It remains unknown how these regions communicate as parts of a system to achieve recognition, but white matter tracts are likely critical to this process. We hypothesized that (1) damage to white matter tracts would be associated with recognition impairment and (2) the degree of disconnection of association fiber tracts [inferior longitudinal fasciculus (ILF) and/or inferior fronto-occipital fasciculus (IFOF)] connecting the visual cortex with emotion-related regions would negatively correlate with recognition performance. One hundred three patients with focal, stable brain lesions mapped onto a reference brain were tested on their recognition of six basic emotional facial expressions. Association fiber tracts from a probabilistic atlas were coregistered to the reference brain. Parameters estimating disconnection were entered in a general linear model to predict emotion recognition impairments, accounting for lesion size and cortical damage. Damage associated with the right IFOF significantly predicted an overall facial emotion recognition impairment and specific impairments for sadness, anger, and fear. One subject had a pure white matter lesion in the location of the right IFOF and ILF. He presented specific, unequivocal emotion recognition impairments. Additional analysis suggested that impairment in fear recognition can result from damage to the IFOF and not the amygdala. Our findings demonstrate the key role of white matter association tracts in the recognition of the facial expression of emotion and identify specific tracts that may be most critical.
Estradiol-Induced Estrogen Receptor-α Trafficking
Authors: Bondar Galyna , Kuo John , Hamid Naheed , Micevych Paul
Published: December 2009

Estradiol has rapid actions in the CNS that are mediated by membrane estrogen receptors (ERs) and activate cell signaling pathways through interaction with metabotropic glutamate receptors (mGluRs). Membrane-initiated estradiol signaling increases the free cytoplasmic calcium concentration ([Ca2+]i) that stimulates the synthesis of neuroprogesterone in astrocytes. We used surface biotinylation to demonstrate that ERα has an extracellular portion. In addition to the full-length ERα [apparent molecular weight (MW), 66 kDa], surface biotinylation labeled an ERα-immunoreactive protein (MW, ∼52 kDa) identified by both COOH- and NH2-directed antibodies. Estradiol treatment regulated membrane levels of both proteins in parallel: within 5 min, estradiol significantly increased membrane levels of the 66 and 52 kDa ERα. Internalization, a measure of membrane receptor activation, was also increased by estradiol with a similar time course. Continuous treatment with estradiol for 24–48 h reduced ERα levels, suggesting receptor downregulation. Estradiol also increased mGluR1a trafficking and internalization, consistent with the proposed ERα–mGluR1a interaction. Blocking ER with ICI 182,780 or mGluR1a with LY 367385 prevented ERα trafficking to and from the membrane. Estradiol-induced [Ca2+]iflux was also significantly increased at the time of peak ERα activation/internalization. These results demonstrate that ERα is present in the membrane and has an extracellular portion. Furthermore, membrane levels and internalization of ERα are regulated by estradiol and mGluR1a ligands. The pattern of trafficking into and out of the membrane suggests that the changing concentration of estradiol during the estrous cycle regulates ERα to augment and then terminate membrane-initiated signaling.
Outwardly Rectifying Tonically Active GABAAReceptors in Pyramidal Cells Modulate Neuronal Offset, Not Gain
Authors: Pavlov Ivan , Savtchenko Leonid P. , Kullmann Dimitri M. , Semyanov Alexey , Walker Matthew C.
Published: December 2009

Hippocampal pyramidal cell excitability is regulated both by fast synaptic inhibition and by tonically active high-affinity extrasynaptic GABAAreceptors. The impact of tonic inhibition on neuronal gain and offset, and thus on information processing, is unclear. Offset is altered by shunting inhibition, and the gain of a neuronal response to an excitatory input can be modified by changing the level of “background” synaptic noise. Therefore, tonic activation of GABAAreceptors would be expected to modulate offset and, in addition, to alter gain through a shunting effect on synaptic noise. Here we show that tonically active GABAAreceptors in CA1 pyramidal cells show marked outward rectification, while the peaks of IPSCs exhibit a linear current–voltage relationship. As a result, tonic GABAAreceptor-mediated currents have a minimal effect upon subthreshold membrane potential variation due to synaptic noise, but predominantly affect neurons at spiking threshold. Consistent with this, tonic GABAAreceptor-mediated currents in pyramidal cells exclusively affect offset and not gain. Modulation of tonically active GABAAreceptors by fluctuations in extracellular GABA concentrations or neuromodulators acting on high-affinity receptors potentially provides a powerful mechanism to alter neuronal offset independently of neuronal gain.
Twinfilin 2 Regulates Actin Filament Lengths in Cochlear Stereocilia
Authors: Peng Anthony W. , Belyantseva Inna A. , Hsu Patrick D. , Friedman Thomas B. , Heller Stefan
Published: December 2009

Inner ear sensory hair cells convert mechanical stimuli into electrical signals. This conversion happens in the exquisitely mechanosensitive hair bundle that protrudes from the cell's apical surface. In mammals, cochlear hair bundles are composed of 50–100 actin-filled stereocilia, which are organized in three rows in a staircase manner. Stereocilia actin filaments are uniformly oriented with their barbed ends toward stereocilia tips. During development, the actin core of each stereocilium undergoes elongation due to addition of actin monomers to the barbed ends of the filaments. Here we show that in the mouse cochlea the barbed end capping protein twinfilin 2 is present at the tips of middle and short rows of stereocilia from postnatal day 5 (P5) onward, which correlates with a time period when these rows stop growing. The tall stereocilia rows, which do not display twinfilin 2 at their tips, continue to elongate between P5 and P15. When we expressed twinfilin 2 in LLC/PK1-CL4 (CL4) cells, we observed a reduction of espin-induced microvilli length, pointing to a potent function of twinfilin 2 in suppressing the elongation of actin filaments. Overexpression of twinfilin 2 in cochlear inner hair cells resulted in a significant reduction of stereocilia length. Our results suggest that twinfilin 2 plays a role in the regulation of stereocilia elongation by restricting excessive elongation of the shorter row stereocilia thereby maintaining the mature staircase architecture of cochlear hair bundles.
Plasticity between Neuronal Pairs in Layer 4 of Visual Cortex Varies with Synapse State
Authors: Sáez Ignacio , Friedlander Michael J.
Published: December 2009

In neocortex, the induction and expression of long-term potentiation (LTP) and long-term depression (LTD) vary depending on cortical area and laminae of presynaptic and postsynaptic neurons. Layer 4 (L4) is the initial site of sensory afference in barrel cortex and primary visual cortex (V1) in which excitatory inputs from thalamus, L6, and neighboring L4 cells are integrated. However, little is known about plasticity within L4. We studied plasticity at excitatory synaptic connections between pairs and triplets of interconnected L4 neurons in guinea pig V1 using a fixed delay pairing protocol. Plasticity outcomes were heterogeneous, with some connections undergoing LTP (n= 7 of 42), some LTD (n= 19 of 42), and some not changing (n= 16 of 42). Although quantal analysis revealed both presynaptic and postsynaptic plasticity expression components, reduction in quantal size (a postsynaptic property) contributing to LTD was ubiquitous, whereas in some cell pairs, this change was overridden by an increase in the probability of neurotransmitter release (a presynaptic property) resulting in LTP. These changes depended on the initial reliability of the connections: highly reliable connections depressed with contributions from presynaptic and postsynaptic effects, and unreliable connections potentiated as a result of the predominance of presynaptic enhancement. Interestingly, very strong, reliable pairs of connected cells showed little plasticity. Pairs of connected cells with a common presynaptic or postsynaptic L4 cell behaved independently, undergoing plasticity of different or opposite signs. Release probability of a connection with initial 100% failure rate was enhanced after pairing, potentially avoiding silencing of the presynaptic terminal and maintaining L4–L4 synapses in a broader dynamic range.
Trial-to-Trial Variability of Single Cells in Motor Cortices Is Dynamically Modified during Visuomotor Adaptation
Authors: Mandelblat-Cerf Yael , Paz Rony , Vaadia Eilon
Published: December 2009

Neurons in all brain areas exhibit variability in their spiking activity. Although part of this variability can be considered as noise that is detrimental to information processing, recent findings indicate that variability can also be beneficial. In particular, it was suggested that variability in the motor system allows for exploration of possible motor states and therefore can facilitate learning and adaptation to new environments. Here, we provide evidence to support this idea by analyzing the variability of neurons in the primary motor cortex (M1) and in the supplementary motor area (SMA-proper) of monkeys adapting to new rotational visuomotor tasks. We found that trial-to-trial variability increased during learning and exhibited four main characteristics: (1) modulation occurred preferentially during a delay period when the target of movement was already known, but before movement onset; (2) variability returned to its initial levels toward the end of learning; (3) the increase in variability was more apparent in cells with preferred movement directions close to those experienced during learning; and (4) the increase in variability emerged at early phases of learning in the SMA, whereas in M1 behavior reached plateau levels of performance. These results are highly consistent with previous findings that showed similar trends in variability across a population of neurons. Together, the results strengthen the idea that single-cell variability can be much more than mere noise and may be an integral part of the underlying mechanism of sensorimotor learning.
Fate of Mammalian Cochlear Hair Cells and Stereocilia after Loss of the Stereocilia
Authors: Jia Shuping , Yang Shiming , Guo Weiwei , He David Z. Z.
Published: December 2009

Cochlear hair cells transduce mechanical stimuli into electrical activity. The site of hair cell transduction is the hair bundle, an array of stereocilia with different height arranged in a staircase. Tip links connect the apex of each stereocilium to the side of its taller neighbor. The hair bundle and tip links of hair cells are susceptible to acoustic trauma and ototoxic drugs. It has been shown that hair cells in lower vertebrates and in the mammalian vestibular system may survive bundle loss and undergo self-repair of the stereocilia. Our goals were to determine whether cochlear hair cells could survive the trauma and whether the tip link and/or the hair bundle could be regenerated. We simulated the acoustic trauma-induced tip link damage or stereociliary loss by disrupting tip links or ablating the hair bundles in the cultured organ of Corti from neonatal gerbils. Hair-cell fate and stereociliary morphology and function were examined using confocal and scanning electron microscopies and electrophysiology. Most bundleless hair cells survived and developed for ∼2 weeks. However, no spontaneous hair-bundle regeneration was observed. When tip links were ruptured, repair of tip links and restoration of mechanotransduction were observed in <24 h. Our study suggests that the dynamic nature of the hair cell's transduction apparatus is retained despite the fact that regeneration of the hair bundle is lost in mammalian cochlear hair cells.