bluuebunny/crossref_metadata_2025 huggingface dataset:
Pre‐school staffs’ attitudes toward foods in relation to the pedagogic meal
Authors: Sepp Hanna , Abrahamsson Lillemor , Fjellström Christina
Published: October 2005

The aim of this study, with the pedagogic meal in focus, was to identify pre‐school staff members’ attitudes to the role of food and meals as part of daily activities at pre‐school. Interviews were carried out at 12 pre‐schools and a total of 34 pre‐school staff participated. The staff revealed strong opinions as well as ambivalence towards how food and meals should best be integrated into their daily work and pedagogic activities. The pre‐school staffs’ lack of or insufficient education and knowledge regarding food and nutrition resulted in an ambivalent and uncertain situation with respect to how they should see themselves as teachers in the meal situation. Nevertheless, most of the staff had a clear perception of what it meant to practice a pedagogic meal. It meant helping and encouraging the children to help themselves and serving as an adult model for the children at table, though this pedagogic activity was uncommon. While the staff were satisfied with the pre‐schools’ role of catering for the children, they expressed concern about or even mistrust towards the children's parents. Despite, or perhaps due to, their inadequate knowledge about food and nutrition and the lack of specific aims for the pedagogic meal, they assumed that the public sector was a better educational institution regarding foods and a better guarantor for children's food habits and dietary intake. As the teachers’ identities have changed over the past years they have not yet found a solid ground for determining how food and meals could be integrated into their everyday work as pre‐school teachers and childminders.
Cellular phone etiquette among college students
Authors: Lipscomb Thomas J. , Totten Jeff W. , Cook Roy A. , Lesch William
Published: October 2005

There has been tremendous growth in the cellular telephone industry in recent years. This evolving technology has given rise to concerns over the social rules of etiquette governing cellphone usage behaviour. The present study was undertaken to better understand the perceptions of cellphone usage propriety among one of the most important target markets for cellphone products – young adults attending college. Data were collected from a total of 383 cellphone consumers residing in geographically diverse regions of the United States. Overall, the results indicated a high degree of agreement among respondents as to appropriate and inappropriate situations for cellphone usage. Respondents considered inappropriate situations for cellphone usage to include during worship/church, during class, in a library and in a movie theatre during a movie. Respondents considered it to be appropriate to use cellphones while on public transportation, in a supermarket, and to use a hands‐free set while driving. Specific differences were found as a function of geographic regions, gender and employment status.
3D milk‐fouling model of plate heat exchangers using computational fluid dynamics
Authors: JUN SOOJIN , PURI VIRENDRA M
Published: October 2005

A 3D fouling model for milk pasteurization using PHEs (plate heat exchangers) was developed using CFD (computational fluid dynamics). Based on the hydrodynamic and thermodynamic performances of PHEs in a 3D environment, the chemical reaction equations employed for protein denaturation and absorption onto the stainless steel surface were coupled using the fluent software. The 10‐channel PHE system with both counter‐current and cocurrent flows was applied to validate the model by visualizing and quantifying the milk deposit formulated in the fluid channels. The predicted mass deposit values were in good agreement with the experimental data with the prediction error of 0.01 g or 1%. The simulation results based on new PHE system, designed for the uniformity of flow distribution, showed the deposited mass could be reduced to 1/10, compared to the current system under identical energy condition. Although the computational efforts required were quite intensive, the 3D fouling model was validated as an effective tool for design of new plate shape and corrugation profile optimized for minimizing milk fouling.
Influence of tribomechanical micronization on the physical and functional properties of whey proteins
Authors: HERCEG Z , LELAS V , KREŠIĆ G
Published: October 2005

Because of their high nutritional value and commercially important functional properties, whey proteins are of high interest nowadays. Whey protein concentrates (WPCs) containing 60% and 80% proteins (WPC‐60 and WPC‐80, respectively) were treated using laboratory equipment for tribomechanical micronization and activation (TMA) with three different rotor speeds: 16 000, 20 000 and 22 000 r.p.m. The results showed that the TMA treatment causes a significant decrease (  P < 0.05) in particle size, a change in particle size distribution and an increase in specific area of WPC. As a consequence of the TMA process, rupturing of protein globules and the appearance of a greater number of protein fragments occurred. The solubility, dispersibility, foaming and emulsifying properties of tribomechanically treated whey protein concentrates (TWPCs) were also modified. The results of particle analysis confirmed that a decrease in particle size correlates with an improvement of the foaming properties. These changes in the treated materials depend on the type of the WPCs used and the rotor speed of the TMA equipment. The most obvious changes were observed in samples treated at the maximum rotor speed of the TMA equipment.
Factors affecting lactoperoxidase activity
Authors: FONTEH FLORENCE A , GRANDISON ALISTAIR S , LEWIS MICHAEL J
Published: October 2005

The extent to which lactoperoxidase (LP) activity was affected while varying the concentration of various compounds normally present in the reaction medium was investigated. LP activity increased with increasing concentrations of 2,2′‐azino‐bis‐3‐ethylbenz‐thiazoline‐6‐sulphonic acid (ABTS) but decreased with increasing thiocyanate concentrations. Maximum activity was at 0.1 mm for peroxide. Activity increased in the presence of lactose, whey protein concentrate, sodium, magnesium and calcium chlorides, but decreased in the presence of casein. Activity was similar in either acetate or phosphate buffers but higher in either citrate or succinate buffers. These compounds influence LP activity and should be considered when optimum activity conditions are being established.
12‐O‐tetradecanoyl‐phorbol‐13‐acetate‐dependent up‐regulation of dopaminergic gene expression requires Ras and neurofibromin in human IMR‐32 neuroblastoma
Authors: Mangoura Dimitra , Theofilopoulos Spyros , Karouzaki Sophia , Tsirimonaki Emmanouella
Published: October 2005

The dopaminergic transcriptional programme is highly regulated during development and in the adult, in response to activation of membrane receptor signalling cascades. Gene expression of tyrosine hydroxylase (TH), the rate‐limiting enzyme in dopamine synthesis, is known to be regulated by receptors that act through protein kinase C (PKC) or Ras signalling. To investigate possible interactions between these two pathways before they converge on Raf activation, we evaluated whether phorbol ester (12‐O‐tetradecanoyl‐phorbol‐13‐acetate, TPA)‐dependent PKC activation required Ras for regulation of TH expression in IMR‐32 cells. We found that long‐term treatment with TPA, which induces down‐regulation of PKC‐α, led to induction of both protein and message levels of TH by autocrine factors. This was dependent on endogenous Ras, but independent of the transcription factor Nurr1. Moreover, this mechanism of action mimicked the effects of overexpression of the Ras‐GAP domain of neurofibromin, GAP‐related domain (GRD) I, which is part of the upstream mechanism for regulation of Ras activation and a PKC‐α substrate. Overexpression of Ras also led to transcriptional and translational up‐regulation of TH, independent of Nurr1 induction, as well as distinct phenotypic changes consistent with cell hypertrophy and increased secretory activity shown by induction of expression of vesicular monoamine transporter 2 and synaptosomal‐associated protein‐25. Most interestingly, overexpression of GRDI and down‐regulation of the endogenous GRDII neurofibromin led to significant increases in Nurr1 message, possibly reflecting a transcriptional hierarchy during development. Taken together, these studies suggest that PKC‐α, neurofibromin and Ras are essential in regulation of TH gene expression in IMR‐32 cells.
Microtubule affinity‐regulating kinase 1 (MARK1) is activated by electroconvulsive shock in the rat hippocampus
Authors: Jeon Songhee , Kim Yong‐Sik , Park Joobae , Bae Chang‐Dae
Published: October 2005

Electroconvulsive shock (ECS) induces phosphorylation and dephosphorylation of many signaling molecules in the rat brain. While studying phosphorylated proteins in the rat brain after ECS, we observed a 100‐kDa protein that cross‐reacted with anti‐phospho‐p70 S6 kinase antibody, which was subsequently purified and identified as microtubule affinity‐regulating kinase 1 (MARK1). Purified MARK1 was phosphorylated at the Ser and Thr residues. MARK1 activation and subsequent Tau phosphorylation in the hippocampus after ECS was confirmed by an in‐gel kinase assay using tau protein as a substrate. MARK1 was maximally activated between 2 and 5 min after ECS, and Tau phosphorylation at Ser262 was also increased at 2 min and lasted to 1 h after ECS. Taken together, we concluded that ECS activated MARK1 and subsequently phosphorylated Tau at Ser262. Both MARK1 activity and Tau phosphorylation were increased in the rat hippocampus after chronic ECS where axonal remodeling was apparent. In order to investigate the physiologic stimuli which are involved in the activation of MARK1, SH‐SY 5Y cells were treated with brain‐derived neurotrophic factor or 60 mm KCl. Both stimuli were capable of inducing MARK activation.
Parents’ and Clinicians’ Perception of Severity of Referral Problems
Authors: Maguire Siobain , Guishard‐Pine Jeune
Published: October 2005

Background:  Referral meetings are commonly used in CAMH Services to allocate a priority rating that reflects urgency, and thus severity, of the referral. Whilst it is recognised that a system is needed to manage the current level of demand, the literature suggests that decisions about severity are often inaccurate.

Method:  The current study aimed to evaluate a CAMHS referral system by looking at whether the priority ratings allocated by the Multi‐Disciplinary Team (MDT) accorded with the parents’ and the individual clinician's perception of the severity of the child's difficulties. Data were taken from the Service's outcome database.

Results:  The results showed that priority ratings did not reflect the parents’ and the individual clinician's perception of the problem. It is therefore suggested that the current system for prioritising referrals requires some reform.

Conclusion:  There is discussion of procedures that might improve the accuracy of the priority rating process, such as using scores on standardised measures as part of the decision‐making process.
Use of Psychotropic Medication in an Outpatient CAMHS Over a 5‐Year Period
Authors: Sivaprasad Leela , Kolind Annette , Berg Birgit
Published: October 2005

Background:  Psychotropic medication is being prescribed with increasing frequency for children and adolescents but there are very few prescription reviews on the extent of use in the UK.

Method:  A retrospective prescriptions’ survey was carried out in an outpatient CAMHS in three time‐bands between 1997 and 2002.

Results:  We found a five‐fold increase in the number of prescriptions, a ten‐fold increase in the number of young people prescribed medications, and a dramatic increase in the range of psychotropics prescribed.

Conclusions:  There is a need to further evaluate prescribing for children and adolescents in the UK. Clearer guidelines should be developed to ensure safe practices.
Reflections on the Challenges of Effective Dissemination of Behavioural Family Intervention: Our Experience with the Triple P – Positive Parenting Program
Authors: Sanders Matthew R. , Turner Karen M. T.
Published: October 2005

This paper draws on learnings from dissemination and diffusion research to discuss predictors of dissemination outcomes, obstacles to effective dissemination, and phases of dissemination failure. A model is presented of effective dissemination of a multilevel system of intervention known as the Triple P‐Positive Parenting Program (Triple P). This model takes a systems‐contextual approach, addressing program design, skills training, practitioner confidence and self‐regulation, and workplace support. Recommendations are made for agencies adopting evidence‐based programs, particularly in relation to the selection, establishment and maintenance of new programs as well as guiding ongoing program development. Future directions for research into the dissemination of evidence‐based practice are also discussed.
Self Esteem/Self Concept Scales for Children and Adolescents: A Review
Authors: Butler Richard J. , Gasson Sarah L.
Published: October 2005

There remains a flourishing interest in self esteem/self concept both in academic and clinical circles and popular literature. This paper elaborates various notions of the self and discusses the principles underpinning ways of measuring self esteem/self concept with children and adolescents. A review over the last 20 years indicates a raft of scales currently employed. The 14 most frequently cited are considered, with the top six measures and the latest British scale discussed in detail. The paper highlights issues and themes emerging from a comprehensive analysis of these scales, with a conclusion framed around assisting the reader to make an informed choice.
UK Government Policy and Unaccompanied Adolescents Seeking Asylum
Authors: Kralj Lucy , Goldberg David
Published: October 2005

A series of decisions made by successive UK governments with the aim of reducing the flow of immigration has impacted in countless ways on those seeking asylum. The recently published 5‐year strategy for asylum and immigration (Home Office, 2005) has potentially very serious implications for unaccompanied asylum seeking children with the government making plans to commence routine detention and deportation of these children if their asylum claim is not accepted. This paper aims to lay out recent legislation in relation to the treatment of unaccompanied 16‐ and 17‐year old young people seeking asylum and to outline the complex asylum process negotiated by these young people.
Benefit–Cost in the California Treatment Outcome Project: Does Substance Abuse Treatment “Pay for Itself”?
Authors: Ettner Susan L. , Huang David , Evans Elizabeth , Rose Ash Danielle , Hardy Mary , Jourabchi Mickel , Hser Yih‐Ing
Published: October 2005

Objective. To examine costs and monetary benefits associated with substance abuse treatment.

Data Sources. Primary and administrative data on client outcomes and agency costs from 43 substance abuse treatment providers in 13 counties in California during 2000–2001.

Study Design. Using a social planner perspective, the estimated direct cost of treatment was compared with the associated monetary benefits, including the client's costs of medical care, mental health services, criminal activity, earnings, and (from the government's perspective) transfer program payments. The cost of the client's substance abuse treatment episode was estimated by multiplying the number of days that the client spent in each treatment modality by the estimated average per diem cost of that modality. Monetary benefits associated with treatment were estimated using a pre–posttreatment admission study design, i.e., each client served as his or her own control.

Data Collection. Treatment cost data were collected from providers using the Drug Abuse Treatment Cost Analysis Program instrument. For the main sample of 2,567 clients, information on medical hospitalizations, emergency room visits, earnings, and transfer payments was obtained from baseline and 9‐month follow‐up interviews, and linked to information on inpatient and outpatient mental health services use and criminal activity from administrative databases. Sensitivity analyses examined administrative data outcomes for a larger cohort (N=6,545) and longer time period (1 year).

Principal Findings. On average, substance abuse treatment costs $1,583 and is associated with a monetary benefit to society of $11,487, representing a greater than 7:1 ratio of benefits to costs. These benefits were primarily because of reduced costs of crime and increased employment earnings.

Conclusions. Even without considering the direct value to clients of improved health and quality of life, allocating taxpayer dollars to substance abuse treatment may be a wise investment.
A Needle in a Haystack? Uninsured Workers in Small Businesses That Do Not Offer Coverage
Authors: Kronick Richard , Olsen Louis C.
Published: October 2005

Objective. To describe the insurance status of workers at small businesses, and to describe the status of uninsured persons by the employment characteristics (employment status, firm size, and whether the employer offers insurance) of the head of household.

Data Sources. Data from the March and February 2001 Current Population Survey, and a survey of 2,830 small businesses in San Diego County conducted in 2001.

Study Design. The survey of small businesses was undertaken as part of a project testing the response of employers to offers of subsidized coverage. Employers were asked whether they offered insurance, and about the insurance status of their employees. The merged February–March 2001 CPS was used to identify the employment status, firm size, and employer‐offering status for uninsured persons in the U.S.

Data Collection. Telephone interviews with small businesses in San Diego County.

Principal Findings. Only 21 percent of the uninsured in the U.S. are full‐time employees (or their dependents) in small businesses (<100 employees) that do not offer insurance. The employment status of the uninsured is heterogeneous: many work for large employers, small employers who do offer insurance, or are self‐employed, part‐time workers, or have no workers in the household. Although there are many small businesses in San Diego that do not offer coverage, most of them have very few uninsured workers. Over 50 percent of businesses that do not offer coverage have either zero or one uninsured worker. There are very few small businesses that do not offer coverage and that have substantial numbers of uninsured workers. These businesses are not quite as rare as a needle in a haystack, but they are very difficult to find.

Conclusions. If all small businesses that do not offer insurance now could be persuaded to start offering coverage, and if all the full‐time workers (and their dependents) in those businesses accepted insurance, the number of uninsured would decline by 21 percent—a significant decline, but leaving 80 percent of the problem untouched. If the prime target for programs of subsidized insurance are small businesses that do not offer coverage now and that have substantial numbers of uninsured workers, the target is very small.
Disparities in Use of and Unmet Need for Therapeutic and Supportive Services among School‐Age Children with Functional Limitations: A Comparison across Settings
Authors: Benedict Ruth E.
Published: October 2005

Objectives. To determine whether family resources predict use of therapeutic and supportive services and unmet needs in medical versus educational settings.

Data Source. Children 5–17 years of age with at least one functional limitation (n=3,434) from the 1994 to 1995 Disability Supplement to the U.S. National Health Interview Survey.

Study Design. Family resources included the child's type of health insurance, household education level, and poverty status. Therapeutic services included audiology; social work; occupational, physical, or speech therapy. Supportive services included special equipment, personal care assistance, respite care, transportation, or environmental modifications. Need was controlled by child health status and the severity and type of functional limitation(s). Age, gender, race/ethnicity, family size, and structure were covariates.

Data Analysis Methods. Logistic regression provided estimates of associations between‐family resources and use of or unmet need for therapeutic and supportive services. Multinomial methods were used to determine therapeutic service outcomes in medical versus educational settings.

Principal Findings. Children with public insurance were two to three times more likely to use services than children with private or no insurance regardless of type of service. Household education and public insurance were associated with supportive and therapeutic service use, but for therapeutic services only among children receiving services beyond the school setting. Household education predicted unmet need for both types of services and therapeutic services across settings. Findings should be interpreted cautiously, given the survey's dependence on respondent report to define the need for services and the potential for overrepresentation of children with more severe needs in the public insurance category.

Conclusions. Disparities in the use of services by household education level and by type of health insurance across service settings suggests inequitable access among the U.S. policies and programs serving children with functional limitations. Family income and education appear to give families an advantage in obtaining services and in identifying a child's unmet need.
The Influence of Comorbid Chronic Medical Conditions on the Adequacy of Depression Care for Older Americans
Authors: Harman Jeffrey S. , Edlund Mark J. , Fortney John C. , Kallas Henrique
Published: October 2005

Objectives: To assess the effect of the co‐occurrence of four common chronic medical conditions (hypertension, diabetes mellitus, arthritis, heart disease) on the probability of receiving adequate depression treatment.

Design: Retrospective analysis of the 2000 and 2001 Medical Expenditure Panel Surveys (MEPS).

Setting: Households in the United States.

Participants: MEPS respondents aged 65 and older with self‐reported depression (N=498).

Measurements: Adequate depression treatment is defined as receiving eight psychotherapy sessions or filling at least four antidepressant prescriptions at a minimally adequate dosage. Comorbid diabetes mellitus, hypertension, heart disease, and arthritis in older persons with depression were identified from patient self‐report.

Results: An estimated 34% (95% confidence interval=28–39%) of older persons with self‐reported depression received an adequate course of depression treatment during a calendar year. Having hypertension or diabetes mellitus was associated with significantly greater odds of receiving adequate depression care (hypertension odds ratio (OR)=1.81, P=.02; diabetes mellitus OR=1.77, P=.03). Having heart disease or arthritis was not significantly associated with the odds of receiving adequate depression care.

Conclusion: Some chronic medical conditions are associated with a greater likelihood of receiving adequate depression care; comorbid medical conditions do not result in lower quality of depression treatment in older persons. The high prevalence rates of comorbid depression and low rates of adequate depression care in elderly persons with chronic illnesses point to the importance of improving primary care depression treatment or enhancing specialty mental health referral.
A Novel Design for Estimating Relative Accuracy of Screening Tests When Complete Disease Verification Is Not Feasible
Authors: Alonzo Todd A. , Kittelson John M.
Published: October 2005

SummaryThe accuracy (sensitivity and specificity) of a new screening test can be compared with that of a standard test by applying both tests to a group of subjects in which disease status can be determined by a gold standard (GS) test. However, it is not always feasible to administer a GS test to all study subjects. For example, a study is planned to determine whether a new screening test for cervical cancer (“ThinPrep”) is better than the standard test (“Pap”), and in this setting it is not feasible (or ethical) to determine disease status by biopsy in order to identify women with and without disease for participation in a study. When determination of disease status is not possible for all study subjects, therelative accuracyof two screening tests can still be estimated by using a paired screen‐positive (PSP) design in which all subjects receive both screening tests, but only have the GS test if one of the screening tests is positive. Unfortunately in the cervical cancer example, the PSP design is also infeasible because it is not technically possible to administer both the ThinPrep and Pap at the same time. In this article, we describe a randomized paired screen‐positive (RPSP) design in which subjects are randomized to receive one of the two screening tests initially, and only receive the other screening test and GS if the first screening test is positive. We derive maximum likelihood estimators and confidence intervals for the relative accuracy of the two screening tests, and assess the small sample behavior of these estimators using simulation studies. Sample size formulae are derived and applied to the cervical cancer screening trial example, and the efficiency of the RPSP design is compared with other designs.
SIMPLE GENERALIZATIONS OF LORENTZ TRANSFORMATIONS AND THEIR IMPLICATIONS FOR HIGH ENERGY EXPERIMENTS
Authors: SCHMITT DANIEL T. , HSU JONG-PING
Published: October 2005

Based on Lorentz and Poincaré invariance, we discuss reference frames with constant-linear-accelerations and their generalized space–time transformations with minimal departure from the Lorentz transformations. The requirement of limiting four-dimensional symmetry of the Lorentz and Poincaré groups assures that the generalized transformations reduce to the Lorentz transformations in the limit of zero acceleration. This suggests that the space–time coordinates xμ of accelerated frames are as meaningful as those of inertial frames. A flexibility and "gauge invariance" of the time for noninertial frames are discussed. These properties and the changes in the space–time of accelerated frames are shown graphically, including singularities and horizons. Physical implications of various accelerated transformations related to accelerated lifetime or decay-length dilations are predicted for experimental test.
BLACK HOLE EVAPORATION BASED UPON A q-DEFORMATION DESCRIPTION
Authors: ZHANG XIN
Published: October 2005

A toy model based upon the q-deformation description for studying the radiation spectrum of black hole is proposed. The starting point is to make an attempt to consider the space–time noncommutativity in the vicinity of black hole horizon. We use a trick that all the space–time noncommutative effects are ascribed to the modification of the behavior of the radiation field of black hole and a kind of q-deformed degrees of freedom are postulated to mimic the radiation particles that live on the noncommutative space–time, meanwhile the background metric is preserved as usual. We calculate the radiation spectrum of Schwarzschild black hole in this framework. The new distribution deviates from the standard thermal spectrum evidently. The result indicates that some correlation effect will be introduced to the system if the noncommutativity is taken into account. In addition, an infrared cutoff of the spectrum is the prediction of the model.
PHASE TRANSITION IN GAUGE THEORIES, MONOPOLES AND THE MULTIPLE POINT PRINCIPLE
Authors: DAS C. R. , LAPERASHVILI L. V.
Published: October 2005

This review is devoted to the Multiple Point Principle (MPP), according to which several vacuum states with the same energy density exist in Nature. The MPP is implemented to the Standard Model (SM), Family replicated gauge group model (FRGGM) and phase transitions in gauge theories with/without monopoles. Using renormalization group equations for the SM, the effective potential in the two-loop approximation is investigated, and the existence of its postulated second minimum at the fundamental scale is confirmed. Phase transitions in the lattice gauge theories are reviewed. The lattice results for critical coupling constants are compared with those of the Higgs monopole model, in which the lattice artifact monopoles are replaced by the point-like Higgs scalar particles with magnetic charge. Considering our (3+1)-dimensional space–time as, in some way, discrete or imagining it as a lattice with a parameter a = λP, where λP is the Planck length, we have investigated the additional contributions of monopoles to the β-functions of renormalization group equations for running fine structure constants αi(μ) (i = 1, 2, 3 correspond to the U (1), SU(2) and SU(3) gauge groups of the SM) in the FRGGM extended beyond the SM at high energies. It is shown that monopoles have N fam times smaller magnetic charge in the FRGGM than in the SM (N fam is a number of families in the FRGGM). We have estimated also the enlargement of a number of fermions in the FRGGM leading to the suppression of the asymptotic freedom in the non-Abelian theory. We have reviewed that, in contrast to the case of the Anti-grand-unified-theory (AGUT), there exists a possibility of unification of all gauge interactions (including gravity) near the Planck scale due to monopoles. The possibility of the [SU(5)]3 or [SO(10)]3 unification at the GUT-scale ~1018 GeV is briefly considered.
PHENOMENOLOGY OF DOUBLY SPECIAL RELATIVITY
Authors: AMELINO-CAMELIA GIOVANNI , MANDANICI GIANLUCA , PROCACCINI ANDREA , KOWALSKI-GLIKMAN JERZY
Published: October 2005

Investigations of the possibility that some novel "quantum" properties of space–time might induce a Planck-scale modification of the energy/momentum dispersion relation focused at first on scenarios with Planck-scale violations of Lorentz symmetry, with an associated reduced n-parameter (n<6) rotation-boost symmetry group. More recently several studies have also considered the possibility of a "doubly special relativity," in which the modification of the dispersion relation emerges from a framework with both the Planck scale and the speed-of-light scale as characteristic scales of a 6-parameter group of rotation-boost symmetry transformations (a deformation of the Lorentz transformations). For the schemes with broken Lorentz symmetry at the Planck scale there is a large literature on the derivation of experimental limits. Here we show that the analysis of the experimental limits could be significantly different in a doubly-special-relativity framework. We find that the study of photon stability, synchrotron radiation, and threshold conditions for particle production in collision processes, the three contexts which are considered as most promising for constraining the broken-Lorentz-symmetry scenario, should not provide significant constraints on a doubly-special-relativity parameter space. However, certain types of analyses of gamma-ray bursts should be sensitive to the symmetry deformation. A key element of our study is an observation that removes a possible sign ambiguity for the doubly-special-relativity framework. This result also allows us to characterize more sharply the differences between the doubly-special-relativity framework and the framework of κ-Poincaré Hopf algebras, two frameworks which are often confused with each other in the literature.
Use of Stents to Treat Extracranial Cerebrovascular Disease
Authors: Meyers Philip M. , Schumacher H. Christian , Higashida Randall T. , Leary Megan C. , Caplan Louis R.
Published: October 2005

Stent-assisted carotid angioplasty (CAS) is increasingly utilized for hemodynamically significant stenoses of the extracranial carotid artery. Carotid endarterectomy (CEA) is still considered the gold standard in the management of symptomatic hemodynamically significant carotid stenoses. However, endovascular device technology is rapidly evolving and the recent introduction of embolic filtration devices (EFD) proved to reduce periprocedural stroke rates in CAS considerably. Several randomized multicenter trials are currently recruiting patients to compare CAS with EFD to carotid endarterectomy in different cohorts, such as patients at high surgical risk for CEA and those with asymptomatic stenosis. The review presents current developments in CAS.
Advances in Radiation Oncology
Authors: Elshaikh Mohamed , Ljungman Mats , Ten Haken Randall , Lichter Allen S.
Published: October 2005

Advances in radiation oncology have been made on three major fronts: biology, physics, and clinical application. Our biological understanding of how radiation kills cells and how malignant cells avoid damage has identified new targets for therapeutic manipulation. Research in physics has yielded sophisticated methods to direct the deposition of radiation energy in ways that enhance target coverage while minimizing dose to normal structures as much as possible. Intensity-modulated radiation therapy (IMRT) and image-guided radiation therapy represent new paradigms in treatment planning and dose delivery. Clinical management of the cancer patient is multidisciplinary. Increasingly, combinations of radiation and chemotherapy, with or without surgery, are enhancing cure rates, often with preservation of organ function. Taken together, these advances have increased the effectiveness of radiation therapy and promise better treatment results in the future.
FUNCTION OF RETINOID NUCLEAR RECEPTORS: Lessons from Genetic and Pharmacological Dissections of the Retinoic Acid Signaling Pathway During Mouse Embryogenesis
Authors: Mark Manuel , Ghyselinck Norbert B. , Chambon Pierre
Published: October 2005

▪ Abstract  Retinoic acid (RA) is involved in vertebrate morphogenesis, growth, cellular differentiation, and tissue homeostasis. The use of in vitro systems initially led to the identification of nuclear receptor RXR/RAR heterodimers as possible transducers of the RA signal. To unveil the physiological functions of RARs and RXRs, genetic and pharmacological studies have been performed in the mouse. Together, their results demonstrate that (a) RXR/RAR heterodimers in which RXR is either transcriptionally active or silent are involved in the transduction of the RA signal during prenatal development, (b) specific RXRα/RAR heterodimers are required at many distinct stages during early embryogenesis and organogenesis, (c) the physiological role of RA and its receptors cannot be extrapolated from teratogenesis studies using retinoids in excess. Additional cell type–restricted and temporally controlled somatic mutagenesis is required to determine the functions of RARs and RXRs during postnatal life.
Acute hypoxia selectively inhibits KCNA5 channels in pulmonary artery smooth muscle cells
Authors: Platoshyn Oleksandr , Brevnova Elena E. , Burg Elyssa D. , Yu Ying , Remillard Carmelle V. , Yuan Jason X.-J.
Published: October 2005

Acute hypoxia causes pulmonary vasoconstriction in part by inhibiting voltage-gated K+ (Kv) channel activity in pulmonary artery smooth muscle cells (PASMC). The hypoxia-mediated decrease in Kv currents [ IK(V)] is selective to PASMC; hypoxia has little effect on IK(V) in mesenteric artery smooth muscle cells (MASMC). Functional Kv channels are homo- and/or heterotetramers of pore-forming α-subunits and regulatory β-subunits. KCNA5 is a Kv channel α-subunit that forms functional Kv channels in PASMC and regulates resting membrane potential. We have shown that acute hypoxia selectively inhibits IK(V) through KCNA5 channels in PASMC. Overexpression of the human KCNA5 gene increased IK(V) and caused membrane hyperpolarization in HEK-293, COS-7, and rat MASMC and PASMC. Acute hypoxia did not affect IK(V) in KCNA5-transfected HEK-293 and COS-7 cells. However, overexpression of KCNA5 in PASMC conferred its sensitivity to hypoxia. Reduction of Po2 from 145 to 35 mmHg reduced IK(V) by ∼40% in rat PASMC transfected with human KCNA5 but had no effect on IK(V) in KCNA5-transfected rat MASMC (or HEK and COS cells). These results indicate that KCNA5 is an important Kv channel that regulates resting membrane potential and that acute hypoxia selectively reduces KCNA5 channel activity in PASMC relative to MASMC and other cell types. Because Kv channels (including KCNA5) are ubiquitously expressed in PASMC and MASMC, the observation from this study indicates that a hypoxia-sensitive mechanism essential for inhibiting KCNA5 channel activity is exclusively present in PASMC. The divergent effect of hypoxia on IK(V) in PASMC and MASMC also may be due to different expression levels of KCNA5 channels.
Opposite regulation of connexin33 and connexin43 by LPS and IL-1α in spermatogenesis
Authors: Fiorini Celine , Decrouy Xavier , Defamie Norah , Segretain Dominique , Pointis Georges
Published: October 2005

The gap junction proteins, connexins (Cxs), are present in the testis, and among them, Cx43 play an essential role in spermatogenesis. In the present study, we investigated the testicular expression and regulation of another Cx, Cx33, previously described as a negative regulator of gap junction communication. Cx33 mRNA was present in testis and undetectable in heart, liver, ovary, and uterus. In the mature testis, Cx33 was specifically immunolocalized in the basal compartment of the seminiferous tubules, whereas Cx43 was present in both seminiferous tubule and interstitial compartments. During stages IX and X of spermatogenesis, characterized by Sertoli cell phagocytosis of residual bodies, Cx43 was poorly expressed within seminiferous tubules, while Cx33 signal was strong. To evaluate the role of phagocytosis in the control of Cx33 and Cx43 expression, the effect of LPS was analyzed in the Sertoli cell line 42GPA9. We show herein that phagocytosis activation by LPS concomitantly stimulated Cx33 and inhibited Cx43 mRNA levels. These effects appear to have been mediated through IL-1α, because the exposure of Sertoli cells to the IL-1 receptor antagonist partly reversed these effects. IL-1α enhanced and reduced, respectively, the levels of Cx33 and Cx43 mRNA in a time- and dose-dependent manner. These data reveal that Cx33 and Cx43 genes are controlled differently within the testis and suggest that these two Cxs may exert opposite and complementary effects on spermatogenesis.
Ouabain potentiates the activation of ERK1/2 by carbachol in parotid gland epithelial cells; inhibition of ERK1/2 reduces Na+-K+-ATPase activity
Authors: Plourde Deana , Soltoff Stephen P.
Published: October 2005

The Na+-K+-ATPase and the ERK1/2 pathway appear to be linked in some fashion in a variety of cells. The Na+-K+-ATPase inhibitor ouabain can promote ERK1/2 activation. This activation involves Src, intracellular Ca2+ concentration ([Ca2+]i) elevation, reactive oxygen species (ROS) generation, and EGF receptor (EGFR) transactivation. In contrast, ERK1/2 can mediate changes in Na+-K+-ATPase activity and/or expression. Thus signaling between ERK1/2 and Na+-K+-ATPase can occur from either direction. Whether such bidirectionality can occur within the same cell has not been reported. In the present study, we have demonstrated that while ouabain (1 mM) produces only a small (∼50%) increase in ERK1/2 phosphorylation in freshly isolated rat salivary (parotid acinar) epithelial cells, it potentiates the phosphorylation of ERK1/2 by submaximal concentrations of carbachol, a muscarinic receptor ligand that initiates fluid secretion. Although ERK1/2 is only modestly phosphorylated when cells are exposed to 1 mM ouabain or 10−6 M carbachol, the combination of these agents promotes ERK1/2 phosphorylation to near-maximal levels achieved by a log order carbachol concentration. These effects of ouabain are distinct from Na+-K+-ATPase inhibition by lowering extracellular K+, which promotes a rapid and large increase in ERK1/2 phosphorylation. ERK1/2 potentiation by ouabain (EC50 ∼100 μM) involves PKC, Src, and alterations in [Ca2+]i but not ROS generation or EGFR transactivation. In addition, inhibition of ERK1/2 reduces Na+-K+-ATPase activity (measured as stimulation of Qo2 by carbachol and the cationophore nystatin). These results suggest that ERK1/2 and Na+-K+-ATPase may signal to each other in each direction under defined conditions in a single cell type.
Chondrocyte cell death mediated by reactive oxygen species-dependent activation of PKC-βI
Authors: DelCarlo Marcello , Loeser Richard F.
Published: October 2005

Signals generated by the extracellular matrix (ECM) promote cell survival. We have shown that chondrocytes detached from their native ECM and plated without serum at low density on poly-l-lysine undergo significant cell death that is associated with the production of reactive oxygen species (ROS). No cell death or ROS production was observed when cells were plated on fibronectin under the same conditions. Cell death on poly-l-lysine could be completely inhibited with the addition of either antioxidants or inhibitors of specific protein kinase C (PKC) isoforms including PKC-βI. PKC-βI was noted to translocate from the cytosol to the particulate membrane after plating on poly-l-lysine, and this translocation was inhibited by the addition of an antioxidant. Time-course analyses implicated endogenous ROS production as a secondary messenger leading to PKC-βI activation and subsequent chondrocyte cell death. Cell survival on poly-l-lysine was significantly improved in the presence of oligomycin or DIDS, suggesting that ROS production occurred via complex V of the electron transport chain of the mitochondria and that ROS were released to the cytosol via voltage-dependent anion channels. Together, these results represent a novel mechanism by which ROS can initiate cell death through the activation of PKC-βI.
Transition of Homer isoforms during skeletal muscle regeneration
Authors: Bortoloso Elena , Pilati Nadia , Megighian Aram , Tibaldo Elisa , Sandonà Dorianna , Volpe Pompeo
Published: October 2005

Homer represents a new and diversified family of proteins that includes several isoforms, Homer 1, 2, and 3; some of these isoforms have been reported to be present in striated muscles. In this study, the presence of Homer isoforms 1a, 1b/c/d, 2b, and 3 was thoroughly investigated in rat skeletal muscles under resting conditions. Transition in Homer isoforms compositon was studied under experimental conditions of short-term and long-term adaptation, e.g., fatigue and regeneration, respectively. First, we show that Homer 1a was constitutively expressed and was transiently upregulated during regeneration. In C2C12 cell cultures, Homer 1a was also upregulated during formation of myotubes. No change of Homer 1a was observed in fatigue. Second, Homer 1b/c/d and Homer 2b were positively and linearly related to muscle mass change during regeneration, and third, Homer 3 was not detectable under resting conditions but was transiently expressed during regeneration although with a temporal pattern distinct from that of Homer 1a. Thus a switch in Homer isoforms is associated to muscle differentiation and regeneration. Homers may play a role not only in signal transduction of skeletal muscle, in particular regulation of Ca2+ release from sarcoplasmic reticulum (Ward CW, Feng W, Tu J, Pessah IN, Worley PF, and Schneider MF. Homer protein increases activation of Ca2+ sparks in permeabilized skeletal muscle. J Biol Chem 279: 5781–5787, 2004), but also in adaptation.
Laminin-10 and Lutheran blood group glycoproteins in adhesion of human endothelial cells
Authors: Vainionpää Noora , Kikkawa Yamato , Lounatmaa Kari , Miner Jeffrey H. , Rousselle Patricia , Virtanen Ismo
Published: October 2005

Laminin α5-chain, a constituent of laminins-10 and -11, is expressed in endothelial basement membranes. In this study we evaluated the roles of α5 laminins and Lutheran blood group glycoproteins (Lu), recently identified receptors of the laminin α5-chain, in the adhesion of human dermal microvascular and pulmonary artery endothelial cells. Field emission scanning electron microscopy and immunohistochemistry showed that the endothelial cells spread on laminin-10 and formed fibronectin-positive fibrillar adhesion structures. Immunoprecipitation results suggested that the cells produced fibronectin, which they could use as adhesion substratum, during the adhesion process. When the protein synthesis during the adhesion was inhibited with cycloheximide, the formation of fibrillar adhesions on laminin-10 was abolished, suggesting that laminin-10 does not stimulate the formation of any adhesion structures. Northern and Western blot analyses showed that the cells expressed Mr 78,000 and 85,000 isoforms of Lu. Quantitative cell adhesion assays showed that in the endothelial cell adhesion to laminin-10, Lu acted in concert with integrins β1 and αvβ3, whereas in the adhesion to laminin-10/11, Lu and integrin β1 were involved. In the cells adhering to the α5 laminins, Lu and the integrins showed uniform cell surface distribution. These findings indicate that α5 laminins stimulate endothelial cell adhesion but not the formation of fibrillar or focal adhesions. Lu mediates the adhesion of human endothelial cells to α5 laminins in collaboration with integrins β1 and αvβ3.
Immunoblotting PKC-δ: a cautionary note from the bench
Authors: Rybin Vitalyi O. , Steinberg Susan F.
Published: October 2005

Antibodies that specifically recognize signaling proteins (or individual phosphorylation events at specific residues in proteins of interest) have become important tools in the study of signaling pathways. However, the recognition properties of many commercially available antibodies have not been fully characterized. In the course of studies exploring PKC-δ phosphorylation mechanisms in cardiomyocytes, we have demonstrated that a BD Transduction Laboratories anti-PKC-δ MAb (generally viewed as an anti-PKC-δ protein antibody) recognizes PKC-δ in resting, but not in PMA-treated, cardiomyocytes. The observations that PKC-δ immunoreactivity is preserved when cultures are treated with PMA in the presence of a the PKC inhibitor GF-109203X and that PKC-δ immunoreactivity is restored by in vitro acid phosphatase treatment indicate that the epitope recognized by the BD Transduction Laboratories anti-PKC-δ MAb is masked by phosphorylation. The BD Transduction Laboratories MAb is poorly suited for studies that compare PKC-δ expression in resting and agonist-activated samples (or in studies of the relationship between PKC-δ phosphorylation and PKC-δ downregulation) because it artifactually displays PKC-δ phosphorylation as a decline in total PKC-δ protein. Other studies have shown that two anti-PKC-δ-pY311 antibodies (manufactured by Cell Signaling Technology, Beverly, MA, and BioSource International, Camarillo, CA, respectively) specifically recognize stimulus-induced changes in PKC-δ-Y311 phosphorylation on the endogenous PKC-δ enzyme, but the Cell Signaling Technology anti-PKC-δ-pY311 antibody provides a better measure of Y311 phosphorylation in overexpressed PKC-δ. Collectively, these studies have identified features of anti-PKC-δ antibodies that affect the interpretation of immunoblot analysis experiments. These findings related to PKC-δ may be symptomatic of a more pervasive feature of immunoblot analysis studies of phosphoproteins in general.