bluuebunny/crossref_metadata_2025 huggingface dataset:
Systems-level analysis and evolution of the phototransduction network inDrosophila
Authors: Landry Christian R. , Castillo-Davis Cristian I. , Ogura Atsushi , Liu Jun S. , Hartl Daniel L.
Published: February 2007

Networks of interacting genes are responsible for generating life's complexity and for mediating how organisms respond to their environment. Thus, a basic understanding of genetic variation in gene networks in natural populations is important for elucidating how changes at the genetic level map to higher levels of biological organization. Here, using the well-characterized phototransduction network inDrosophila, we analyze variation in gene expression within and between two closely related species,Drosophila melanogasterandDrosophila simulans, under different environmental conditions. Gene expression levels in the pathway are largely conserved between these two sibling species. For most genes in the network, differences in level of gene expression between species are correlated with degree of polymorphism within species. However, one gene encoding the light-induced ion channel TRPL (transient receptor potential-like) shows an excess of expression divergence relative to polymorphism, suggesting a possible role for natural selection in shaping this expression difference between species. Finally, this difference in TRPL expression likely has significant functional consequences, because it is known that a high level of rhabdomeral TRPL leads to increased sensitivity to dim background light and an increased response to a wider range of light intensities. These results provide a preliminary quantification of variation and divergence of gene expression between species in a known gene network and provide a foundation for a system-level understanding of functional and evolutionary change.
Structural characterization of the fission yeast U5.U2/U6 spliceosome complex
Authors: Ohi Melanie D. , Ren Liping , Wall Joseph S. , Gould Kathleen L. , Walz Thomas
Published: February 2007

The spliceosome is a dynamic macromolecular machine that catalyzes the excision of introns from pre-mRNA. The megadalton-sized spliceosome is composed of four small nuclear RNPs and additional pre-mRNA splicing factors. The formation of an active spliceosome involves a series of regulated steps that requires the assembly and disassembly of large multiprotein/RNA complexes. The dynamic nature of the pre-mRNA splicing reaction has hampered progress in analyzing the structure of spliceosomal complexes. We have used cryo-electron microscopy to produce a 29-Å density map of a stable 37S spliceosomal complex from the genetically tractable fission yeast,
Schizosaccharomyces pombe
. Containing the U2, U5, and U6 snRNAs, pre-mRNA splicing intermediates, U2 and U5 snRNP proteins, the Nineteen Complex (NTC), and second-step splicing factors, this complex closely resembles
in vitro
purified mammalian C complex. The density map reveals an asymmetric particle, ≈30 × 20 × 18 nm in size, which is composed of distinct domains that contact each other at the center of the complex.
Regulation of a glutamyl-tRNA synthetase by the heme status
Authors: Levicán Gloria , Katz Assaf , de Armas Merly , Núñez Harold , Orellana Omar
Published: February 2007

Glutamyl-tRNA (Glu-tRNA), formed by Glu-tRNA synthetase (GluRS), is a substrate for protein biosynthesis and tetrapyrrole formation by the C
5
pathway. In this route Glu-tRNA is transformed to δ-aminolevulinic acid, the universal precursor of tetrapyrroles (e.g., heme and chlorophyll) by the action of Glu-tRNA reductase (GluTR) and glutamate semialdehyde aminotransferase. GluTR is a target of feedback regulation by heme. In
Acidithiobacillus ferrooxidans
, an acidophilic bacterium that expresses two GluRSs (GluRS1 and GluRS2) with different tRNA specificity, the intracellular heme level varies depending on growth conditions. Under high heme requirement for respiration increased levels of GluRS and GluTR are observed. Strikingly, when intracellular heme is in excess, the cells respond by a dramatic decrease of GluRS activity and the level of GluTR. The recombinant GluRS1 enzyme is inhibited
in vitro
by hemin, but NADPH restores its activity. These results suggest that GluRS plays a major role in regulating the cellular level of heme.
Pyrrolysine is not hardwired for cotranslational insertion at UAG codons
Authors: Ambrogelly Alexandre , Gundllapalli Sarath , Herring Stephanie , Polycarpo Carla , Frauer Carina , Söll Dieter
Published: February 2007

Pyrrolysine (Pyl), the 22nd naturally encoded amino acid, gets acylated to its distinctive UAG suppressor tRNA
Pyl
by the cognate pyrrolysyl-tRNA synthetase (PylRS). Here we determine the RNA elements required for recognition and aminoacylation of tRNA
Pyl
in vivo
by using the Pyl analog
N
-ε-cyclopentyloxycarbonyl-
l
-lysine. Forty-two
Methanosarcina barkeri
tRNA
Pyl
variants were tested in
Escherichia coli
for suppression of the
lac
amber A24 mutation; then relevant tRNA
Pyl
mutants were selected to determine
in vivo
binding to
M. barkeri
PylRS in a yeast three-hybrid system and to measure
in vitro
tRNA
Pyl
aminoacylation. tRNA
Pyl
identity elements include the discriminator base, the first base pair of the acceptor stem, the T-stem base pair G51:C63, and the anticodon flanking nucleotides U33 and A37. Transplantation of the tRNA
Pyl
identity elements into the mitochondrial bovine tRNA
Ser
scaffold yielded chimeric tRNAs active both
in vitro
and
in vivo
. Because the anticodon is not important for PylRS recognition, a tRNA
Pyl
variant could be constructed that efficiently suppressed the
lac
opal U4 mutation in
E. coli
. These data suggest that tRNA
Pyl
variants may decode numerous codons and that tRNA
Pyl
:PylRS is a fine orthogonal tRNA:synthetase pair that facilitated the late addition of Pyl to the genetic code.
The Trithorax group protein Lid is a trimethyl histone H3K4 demethylase required for dMyc-induced cell growth
Authors: Secombe Julie , Li Ling , Carlos Leni , Eisenman Robert N.
Published: February 2007

The Myc oncoprotein is a potent inducer of cell growth, cell cycle progression, and apoptosis. While many direct Myc target genes have been identified, the molecular determinants of Myc’s transcriptional specificity remain elusive. We have carried out a genetic screen in Drosophila and identified the Trithorax group protein Little imaginal discs (Lid) as a regulator of dMyc-induced cell growth. Lid binds to dMyc and is required for dMyc-induced expression of the growth regulatory gene Nop60B. The mammalian Lid orthologs, Rbp-2 (JARID1A) and Plu-1 (JARID1B), also bind to c-Myc, indicating that Lid–Myc function is conserved. We demonstrate that Lid is a JmjC-dependent trimethyl H3K4 demethylase in vivo and that this enzymatic activity is negatively regulated by dMyc, which binds to Lid’s JmjC domain. Because Myc binding is associated with high levels of trimethylated H3K4, we propose that the Lid–dMyc complex facilitates Myc binding to, or maintenance of, this chromatin context.
Evaluating the perceived role of the nurse consultant through the lived experience of healthcare professionals
Authors: McSherry Rob , Mudd Dave , Campbell Steve
Published: February 2007

Aims and objectives.  This study aimed to evaluate the perceived impact of the nurse consultant through the lived experience of the staff.

Background.  Ambiguities exist about the nature, function and value of the nurse consultant role to the individual, nursing and the UK National Health Service.

Design.  A descriptive qualitative research design was developed to evaluate the perceived impact of the nurse consultant through the lived experience of staff by the use of a 360‐degree semi‐structured interview framework. Interviews were undertaken with executive, senior managers, medical, nursing and allied healthcare professional colleagues. The study was based on three nurse consultants working at a University Hospital in the North East of England. A collaborative purposive sampling technique was used involving 10 participants to provide detailed, objective and relevant information associated with the nurse consultant role.

Findings.  Thirty semi‐structured interviews were undertaken. A thematic analysis using Bowling's approach to deciphering interview data revealed nine primary categories. With the exception of the personal qualities, the nurse consultant brings to the role. A series of generalist themes emerged associated with how the role can be enhanced in the future by involving, informing and engaging staff and by developing a phased approach to implementing and evaluating the role.

Conclusions.  The findings indicate that the continued success of the nurse consultant role is associated with developing a more structured approach to implementation and evaluation within the employing organizations.

Relevance to clinical practice.  Awareness of the nurse consultant should be raised through communication, clarification of expectations by engaging and supporting the staff in the acceptance of the role. Organizationally there should be a more phased approach to establishing, implementing and evaluating the nurse consultant.
Prognostic factors associated with poor graft outcomes in renal recipients with post‐transplant glomerulonephritis
Authors: Requião‐Moura Lúcio R , Moscoso‐Solorzano Grace T , Franco Marcello F , Ozaki Kikumi S , Pacheco‐Silva Alvaro , Kirsztajn Gianna Mastroianni , Câmara Niels O.S.
Published: February 2007

Abstract:  Background:  Little data are available concerning post‐transplantation glomerulonephritis (PTx‐GN) and its prognostic factors associated with graft outcomes.

Methods:  We retrospectively evaluated patients with de novo and recurrent PTx‐GN to identify the factors associated with their negative impact on graft and patient outcomes. PTx‐GN was diagnosed in 55 patients, wherein 17 (31%) had recurrent glomerulonephritis (GN) and 16 (29%) had de novo.

Results:  Our enrolled population consisted of 34 ± 13.7‐yr‐old male patients (72%), on hemodialysis for a median of 18 months (0–204) and mainly grafted from living donors (76%). The median onset time of proteinuria and hematuria was 50 d (10–2160) and 30 d (4–1170), respectively. One‐yr graft survival rates after PTx‐GN diagnosis was 64%. The most frequent de novo GN was membranous GN (26%), while focal segmental glomerulosclerosis was the most frequent recurrent GN (41%), with a very early onset (median of three months). One‐yr graft survival was better in the recurrent disease than in the de novo patients, 76% vs. 55% (p = 0.24). The best predictor factors that correlated with graft survival were: proteinuria <3.5 g [relative risk (RR) = 0.24, p = 0.017], serum creatinine below 2.0 mg/dL (RR = 0.06, p = 0.016) at the time of biopsy and the use of angiotensin‐converting enzyme inhibitors (ACEI) (RR = 0.12, p = 0.005). The use of ACEI markedly improved one‐yr graft survival rates (92% vs. 47%, p < 0.001).

Conclusion:  PTx‐GN has a strong negative impact on kidney graft survival. De novo GN appears to have a poorer prognosis than the recurrent type. Patients who used ACEI showed a better survival rate in the follow‐up.
Reduced dose of foscarnet as preemptive therapy for cytomegalovirus infection following reduced‐intensity cord blood transplantation
Authors: Narimatsu H. , Kami M. , Kato D. , Matsumura T. , Murashige N. , Kusumi E. , Yuji K. , Hori A. , Shibata T. , Masuoka K. , Wake A. , Miyakoshi S. , Morinaga S. , Taniguchi S.
Published: February 2007

Abstract: Although foscarnet is a promising alternative for the treatment of cytomegalovirus (CMV) infection, its toxicity can be significant in patients with advanced age. We retrospectively reviewed medical records of 123 patients (median age of 55; range, 17–79) who received reduced‐intensity cord blood transplantation (RI‐CBT). Patients preemptively received reduced‐dose foscarnet 30 mg/kg twice daily when CMV antigenemia exceeded 10/50,000. Sixty‐three patients developed CMV antigenemia on a median of day 34, and 29 received foscarnet preemptively. The median level of CMV antigenemia at the initiation of foscarnet was 30. Median duration of foscarnet administration was 24 days. Adverse effects included electrolyte abnormalities (n=19), renal impairment (n=13), and skin eruption requiring discontinuation of foscarnet (n=1). Preemptive therapy of foscarnet was completed in 18 patients. Seven patients died during foscarnet use without developing CMV disease. The remaining 3 developed CMV enterocolitis 5, 14, and 17 days after initiation of foscarnet. All of them were successfully treated with ganciclovir or foscarnet. Reduced dose of foscarnet is beneficial to control CMV reactivation following RI‐CBT; however, it has considerable toxicities in RI‐CBT recipients with advanced age. Further studies are warranted to minimize toxicities and identify optimal dosages.
Multisystemic therapy project in Sweden: what factors affect the tendency of social workers to refer subjects to the research project?
Authors: Gustle Lars‐Henry , Hansson Kjell , Sundell Knut , Andrée‐Löfholm Cecilia
Published: February 2007

This article examines some of the factors that may have affected the tendency for social workers to refer adolescents to a randomised controlled study of multisystemic therapy (MST). If we are to improve integration between researchers and the clinical setting in the future, it is important to consider those factors that affect implementation of research projects and evidence‐based treatment methods. Evidence‐based methods that lack the support of clinicians will have problems surviving in clinical practice. In the present study, we found that social workers’ treatment ideology was associated with referral rate. Social workers who sympathised with the ideology on which MST is based referred patients to the project to a greater extent. Moreover, we found that the perception of a good work climate and good social support correlated positively with the referral rate from the unit. The results suggest that when implementing evidence‐based methods, or research projects on treatment methods, researchers should consider whether the method is consistent with the current treatment ideology within the unit. Working conditions in the unit should also be considered.
Drug Transporters in the Epileptic Brain
Authors: Löscher Wolfgang
Published: February 2007

Summary:  Current estimates indicate that up to one‐third of all individuals with epilepsy are refractory to antiepileptic drug (AED) therapy. Moreover, most of these people are resistant to multiple drugs with a wide range of mechanistic actions. These observations suggest that the development of multidrug resistance involves nonspecific, global changes in the brain. The multidrug transporter hypothesis of pharmacoresistant epilepsy proposes that regional‐specific overexpression of drug efflux transporters in the blood–brain barrier limits the brain penetration of AEDs. Consequently, drug concentrations are too low to induce antiepileptic effects at target brain sites. Cumulative clinical and experimental data support this hypothesis and offer novel therapeutic approaches for the treatment of drug‐resistant epilepsy.
Implementation and Evaluation of a Nursing Home Fall Management Program
Authors: Rask Kimberly , Parmelee Patricia A. , Taylor Jo A. , Green Diane , Brown Holly , Hawley Jonathan , Schild Laura , Strothers Harry S. , Ouslander Joseph G.
Published: February 2007

OBJECTIVES: To evaluate the feasibility and effectiveness of a falls management program (FMP) for nursing homes (NHs).

DESIGN: A quality improvement project with data collection throughout FMP implementation.

SETTING: NHs in Georgia owned and operated by a single nonprofit organization.

PARTICIPANTS: All residents of participating NHs.

INTERVENTION: A convenience sample of 19 NHs implemented the FMP. The FMP is a multifaceted quality improvement and culture change intervention. Key components included organizational leadership buy‐in and support, a designated facility‐based falls coordinator and interdisciplinary team, intensive education and training, and ongoing consultation and oversight by advanced practice nurses with expertise in falls management.

MEASUREMENTS: Process‐of‐care documentation using a detailed 24‐item audit tool and fall and physical restraint use rates derived from quality improvement software currently used in all Georgia NHs (MyInnerView).

RESULTS: Care process documentation related to the assessment and management of fall risk improved significantly during implementation of the FMP. Restraint use decreased substantially during the project period, from 7.9% to 4.4% in the intervention NHs (a relative reduction of 44%), and decreased in the nonintervention NHs from 7.0% to 4.9% (a relative reduction of 30%). Fall rates remained stable in the intervention NHs (17.3 falls/100 residents per month at start and 16.4 falls/100 residents per month at end), whereas fall rates increased 26% in the NHs not implementing the FMP (from 15.0 falls/100 residents/per month to 18.9 falls/100 residents per month).

CONCLUSION: Implementation was associated with significantly improved care process documentation and a stable fall rate during a period of substantial reduction in the use of physical restraints. In contrast, fall rates increased in NHs owned by the same organization that did not implement the FMP. The FMP may be a helpful tool for NHs to manage fall risk while attempting to reduce physical restraint use in response to the Centers for Medicare and Medicaid Services quality initiatives.
Light‐chain removal by plasmapheresis in myeloma‐associated renal failure
Authors: Cserti Christine , Haspel Richard , Stowell Christopher , Dzik Walter
Published: February 2007

BACKGROUND: Although plasmapheresis has been recommended to reverse nephrotoxic elevations of serum free light chains (sFLCs), there are scant published data on removal of sFLC measured with modern assays.

STUDY DESIGN AND METHODS: sFLC levels were recorded in two patients with myeloma‐associated renal failure receiving multiple plasmapheresis procedures.

RESULTS: In one patient, presenting with acute renal failure 8 months after diagnosis of κ‐LC myeloma, 16 plasmapheresis procedures neither reduced sFLC levels (percent removal ranging from −70% to +40%) nor improved renal function. In another patient who presented with leukemic immunoglobulin A‐λ myeloma and acute renal failure, sFLC decreased by 30 to 60 percent after each plasmapheresis procedure, but rebounded within 5 to 10 hours. Renal failure occurred despite plasmapheresis, and hemodialysis was required.

CONCLUSIONS: In both patients, plasmapheresis failed to effectively lower sFLC levels. The results provide initial biologic data supporting the conclusions of a recent randomized multicenter clinical trial in which plasmapheresis was an ineffective adjunct to chemotherapy for myeloma‐associated acute renal failure.
Generation of kinins during preparation and storage of whole blood–derived platelet concentrates
Authors: Moreau Marie Eve , Thibault Louis , Désormeaux Anik , Chagnon Miguel , Lemieux Réal , Robillard Pierre , Marceau François , Colman Robert W. , Lepage Yves , Rivard Georges‐Étienne , Adam Albert
Published: February 2007

BACKGROUND: Leukoreduction of platelet (PLT) concentrates (PCs) may be associated with hypotension in recipients, and a role for bradykinin (BK)‐related peptides has been proposed for this side effect.

STUDY DESIGN AND METHODS: The concentration of BK and one of its vasoactive metabolites, des‐arginine9‐BK (des‐Arg9‐BK), was measured in a large number of PCs as a function of leukoreduction and storage duration with specific enzyme immunoassays and complementary techniques.

RESULTS: On Day 0 of storage, kinins were detected in leukoreduced and unfiltered PCs at a concentration lower than 100 pg per mL. During storage, both kinin levels peaked on Day 5 of storage, with a concentration higher than 1 ng per mL in 22 percent of PCs whether filtered on Day 0 or not. Physicochemical and pharmacologic characterizations of immunoreactive kinins confirm their nature. In vitro activation of the contact system of the corresponding PLT‐poor plasma showed that a high kinin concentration on Day 5 of the storage corresponded with a low kinin‐forming capacity of plasma. On Day 7, BK was no longer elevated presumably due to its degradation and the depletion of kinin‐forming capacity of the plasma in stored PCs. The activities of metallopeptidases that metabolize BK‐related peptides in plasma from PCs were at levels similar to those recorded in the plasma of a normal reference population and were unaffected by storage.

CONCLUSION: Storage of PCs contributes to the hydrolysis of high‐molecular‐weight kininogen and generation of pharmacologically relevant BK levels that might pose a hazard in susceptible patients.
Development and Psychometric Properties of an Assessment for Persons With Intellectual Disability—The interRAI ID
Authors: Martin Lynn , Hirdes John P. , Fries Brant E. , Smith Trevor F.
Published: February 2007

Abstract  This paper describes the development of the interRAI‐Intellectual Disability (interRAI ID), a comprehensive instrument that assesses all key domains of interest to service providers relative to a person with an intellectual disability (ID). The authors report on the reliability and validity of embedded scales for cognition, self‐care, aggression, and depression. Four provider agencies volunteered to participate and assessed a total of 160 community‐dwelling adults with ID using the interRAI ID, Dementia Questionnaire for Persons with Mental Retardation, and Reiss Screen for Maladaptive Behavior. All scales had acceptable levels of internal consistency (Cronbach’s alpha 0.74–0.93) and good relationships with the criterion measures (r = 0.50–0.93, p < 0.0001). The development of the interRAI ID represents an important and successful first step toward an integrated, comprehensive, and standardized assessment of adults with ID. Use of this instrument may lead to more appropriate support planning, enhanced communication between various professionals supporting persons with ID, and a more seamless approach to supports across the health and social service systems.
Self‐Determined Roommate Selection for Individuals with Intellectual Disabilities: Barriers and New Directions
Authors: Wiltz James
Published: February 2007

Abstract  In many places, most individuals with intellectual disabilities (ID) who reside in government‐funded housing live with roommates. Selecting roommates can be a complicated task, and the individuals themselves seldom have any input on the decision. Although caregivers often consider self‐determination to be a basic human right for people with ID, many complicated decisions are made without incorporating self‐determination. One difficulty is that people with ID rely on support, whereas the concept of self‐determination places an emphasis on autonomy. Therefore, delineating self‐determination for people with ID involves trying to balance how much support caregivers need to provide in choice making, and it potentially can vary from individual to individual. The reality for people with ID is that the balance of support in self‐determination shifts depending, not on the individual, but on the complexity of the decision being made. Probably as a result, more complicated decisions, including selecting roommates, seldom incorporate self‐determination. This paper highlights the problem, and two barriers to self‐determined roommate selection are identified: (1) waiting lists for residential services, and (2) the scarcity of information that is available on roommate relationships and compatibility. These barriers need to be addressed in order to increase the level of self‐determination in this important life choice.
Effects of Size of Cellulose Granules on Dough Rheology, Microscopy, and Breadmaking Properties
Authors: Seguchi M. , Tabara A. , Fukawa I. , Ono H. , Kumashiro C. , Yoshino Y. , Kusunose C. , Yamane C.
Published: February 2007

ABSTRACT:  Breadmaking was performed with cellulose‐blended wheat flour. Cellulose granules (7 types) of various sizes (diameter) were prepared by kneading. With increase of the blend percent of the cellulose samples from 10% to 20%, breadmaking properties such as bread height and specific volume (SV) gradually decreased in every sample; however, the decreasing levels of the properties in 7 types of various sizes varied. The decrease of bread height and SV was associated with the size of the cellulose granule. It was observed at both 10% and 20% blends that the same bread height and SV as for bread baked with only wheat flour could be obtained when the diameter of cellulose granule was above 154 μm in cellulose/wheat flour breadmaking, while they gradually decreased with granules below 154 μm. When the largest cellulose granules were mechanically ground to make smaller ones, the bread height and SV decreased with increasing grinding time. It was ascertained that the size of the cellulose granule was important for breadmaking properties. Cellulose‐blended wheat flour was subjected to mixograph tests. When cellulose granules above 154‐μm dia were blended with wheat flour, the profile of the mixogram was almost the same as that for wheat flour; that is, the profile had a short mixing requirement and showed a viscous gluten matrix. However, when cellulose granules below 81‐μm dia were blended, a different curve showing a nonviscous dough due to breakdown of the gluten protein was observed, as ascertained by microscopy. Farmograph test showed that the amount of the released gas from cellulose‐blended bread dough increased with decrease of the size of the cellulose granule due to breakdown of the gluten protein.
Food Microstructure Affects the Bioavailability of Several Nutrients
Authors: Parada J. , Aguilera J.M.
Published: February 2007

ABSTRACT:  There is an increased interest in the role that some nutrients may play in preventing or ameliorating the effect of major diseases (for example, some types of cancer, cardiovascular diseases, eye disorders, among others). In this respect, the bioavailability or the proportion of an ingested nutrient that is made available (that is, delivered to the bloodstream) for its intended mode of action is more relevant than the total amount present in the original food. Disruption of the natural matrix or the microstructure created during processing may influence the release, transformation, and subsequent absorption of some nutrients in the digestive tract. Alternatively, extracts of bioactive molecules (for example, nutraceuticals) and beneficial microorganisms may be protected during their transit in the digestive system to the absorption sites by encapsulation in designed matrices. This review summarizes relevant in vivo and in vitro methods used to assess the bioavailability of some nutrients (mostly phytochemicals), types of microstructural changes imparted by processing and during food ingestion that are relevant in matrix‐nutrient interactions, and their effect on the bioavailability of selected nutrients.
Do sensorial manipulations affect subjects differently depending on their postural abilities?
Authors: Paillard Thierry , Bizid Riadh , Dupui Philippe
Published: February 2007

Objectives:To examine whether sensorial manipulation affects subjects differently according to their postural performance and the strategies used. The literature showed that the level of competition of soccer players influences their postural performance and strategy.

Methods:Eight high-level (HL) professional soccer players and nine regional-level (RL) soccer players were tested (1) in a reference condition and (2) in a manipulated sensorial condition (MAN). The MAN condition consisted of perturbing the proprioceptive and exteroceptive information. For each postural condition, balance was assessed by measuring the centre of foot pressure using a force platform during a test of bipedal standing posture.

Results:The postural control was less perturbed in the HL than in the RL players in the two postural conditions. Moreover, the group–condition interaction showed that the postural control was less disturbed in the HL than in the RL players when the sensory information was manipulated.

Conclusions:The HL soccer players probably possessed a better internal model of verticality than the RL players. Subjects who had a better postural control level were less disturbed by sensorial manipulation than the others in postural regulation.
B→Kπ DECAYS IN THE GENERAL AND THE CONSTRAINED MINIMAL SUPERGRAVITY MODEL
Authors: ZOU WENJUAN , XIAO ZHENJUN
Published: February 2007

In this paper, we calculated the supersymmetric contributions to the branching ratios and CP-violating asymmetries of the four B→Kπ decays in both the general and the constrained minimal supergravity (mSUGRA) model. Within the considered parameter space, we found that (a) the phase ϕμin the general mSUGRA model is strongly constrained by the data of the electron and neutron electric dipole moment and the data of B→Xsγ decay: ϕμ<0.1 (<10-3) for the case of small (large) tan β, but no limit on the phase ϕAcan be derived from the above data; (b) in both the general and the constrained mSUGRA model, the SUSY contributions are not large enough to explain the observed B→Kπ puzzle.
BRANS–DICKE THEORY: JORDAN VERSUS EINSTEIN FRAME
Authors: BHADRA A. , SARKAR K. , DATTA D. P. , NANDI K. K.
Published: February 2007

It is well known that, in contrast to general relativity, there are two conformally related frames, the Jordan frame and the Einstein frame, in which the Brans–Dicke theory, a prototype of generic scalar–tensor theory, can be formulated. There is a long standing debate on the physical equivalence of the formulations in these two different frames. It is shown here that gravitational deflection of light to second order accuracy may observationally distinguish the two versions of the Brans–Dicke theory.
RADION INDUCED SPONTANEOUS BARYOGENESIS
Authors: ALBERGHI G. L. , CASADIO R. , TRONCONI A.
Published: February 2007

We describe a possible scenario for spontaneous baryogenesis given by the Randall–Sundrum brane-world model with two branes and a radion stabilizing potential. It is known that the cosmological expansion of the Universe can be recovered in this brane-world model by adding matter on the branes, and time-reversal is then broken. We show here that, as a consequence of such a time dependence of the system, the effective coupling of the radion with matter fields generates a chemical potential with opposite signs for baryons and anti-baryons and spontaneous baryogenesis is therefore induced naturally and self-consistently.
UNDERLYING GAUGE SYMMETRIES OF SECOND-CLASS CONSTRAINTS SYSTEMS
Authors: KRIVORUCHENKO M. I. , FAESSLER AMAND , RADUTA A. A. , FUCHS C.
Published: February 2007

Gauge-invariant systems in unconstrained configuration and phase spaces, equivalent to second-class constraints systems upon a gauge-fixing, are discussed. A mathematical pendulum on an (n-1)-dimensional sphere Sn-1 as an example of a mechanical second-class constraints system and the O(n) nonlinear sigma model as an example of a field theory under second-class constraints are discussed in details and quantized using the existence of underlying dilatation gauge symmetry and by solving the constraint equations explicitly. The underlying gauge symmetries involve, in general, velocity dependent gauge transformations and new auxiliary variables in extended configuration space. Systems under second-class holonomic constraints have gauge-invariant counterparts within original configuration and phase spaces. The Dirac's supplementary conditions for wave functions of first-class constraints systems are formulated in terms of the Wigner functions which admit, as we show, a broad set of physically equivalent supplementary conditions. Their concrete form depends on the manner the Wigner functions are extrapolated from the constraint submanifolds into the whole phase space.
GENERAL COORDINATE TRANSFORMATIONS AS THE ORIGINS OF DARK ENERGY
Authors: RODGERS VINCENT G. J. , YASUDA TAKESHI
Published: February 2007

In this note we demonstrate that the algebra associated with coordinate transformations might contain the origins of a scalar field that can behave as an inflaton and/or a source for dark energy. We will call this particular scalar field the diffeomorphism scalar field. In one dimension, the algebra of coordinate transformations is the Virasoro algebra while the algebra of gauge transformations is the Kac–Moody algebra. An interesting representation of these algebras corresponds to certain field theories that have meaning in any dimension. In particular, the so-called Kac–Moody sector corresponds to Yang–Mills theories and the Virasoro sector corresponds to the diffeomorphism field theory that contains the scalar field and a rank-two symmetric, traceless tensor. We will focus on the contributions of the diffeomorphism scalar field to cosmology. We show that this scalar field can, qualitatively, act as a phantom dark energy, an inflaton, a dark matter source, and the cosmological constant Λ.
A software retrieval service based on adaptive knowledge-driven agents for wireless environments
Authors: Mena Eduardo , Illarramendi Arantza , Royo Jose A. , GoñI Alfredo
Published: February 2007

The ability to retrieve software in an easy and efficient way confers competitive advantage on computer users in general and, even more especially, on users of wireless devices (like some laptops, PDAs, etc.). In this article, we present a software retrieval service that allows users to select and retrieve software in an easy and efficient way, anywhere and anytime. Two relevant components of this service are: 1) a software ontology (software catalog) which provides users with a semantic description of software elements, hiding the location and access method of various software repositories, and 2) a set of specialist agents that allow browsing of the software catalog (automatically customized for each user), and an efficient retrieval method for the selected software. These agents automatically adapt their behavior to different users and situations by considering the profile and preferences of the users and the network status.In summary, our software-obtaining process based on an ontology and autonomous and adaptive agents presents a qualitative advance with respect to existing solutions: our approach adapts to the features of users, relieving them from knowing the technical features of their devices and the location and access method of various remote software repositories.
Fast Cathodoluminescent Calcium Sulfide Phosphors
Authors: Lehmann W. , Ryan F. M.
Published: February 2007

Abstract not Available.
Investigations on the Structure of the Color Compound in Caustic
Authors: Wawzonek S. , Eftax D. S. P.
Published: February 2007

The material isolated by Heller from stubs of graphite anodes used in chlorine‐caustic soda cells and shown by him to give the color in concentrated caustic soda has been reinvestigated. An extract from the stubs after treatment with nitric acid was found to consist of mellitic acid, pentacarboxychloro‐benzene, a tetracarboxychlorobenzene of unknown configuration, and material of unknown structure which is the source of the color. The acids were formed during the treatment with nitric acid. The color forming material seems to be of high molecular weight and structurally more complex than proposed by Heller.
Aldosterone-induced EGFR expression: interaction between the human mineralocorticoid receptor and the human EGFR promoter
Authors: Grossmann Claudia , Krug Alexander W. , Freudinger Ruth , Mildenberger Sigrid , Voelker Katharina , Gekle Michael
Published: February 2007

Aldosterone plays a key role in cardiovascular and renal injury. The underlying mechanisms are not completely understood. Because the epidermal growth factor receptor (EGFR) is involved in the development of fibrosis and vascular dysfunction, upregulation of EGFR expression by aldosterone-bound mineralocorticoid receptor (MR) is an attractive hypothesis. We investigated the effect of aldosterone on EGFR expression in the aorta of adrenalectomized rats and in human aorta smooth muscle cells (HAoSMC) in primary culture. Aldosterone, but not dexamethasone, stimulated EGFR expression in vivo in the aorta as well as in HAoSMC. EGFR degradation was not affected. Aldosterone-induced EGFR expression in HAoSMC was dose dependent and prevented by spironolactone. Furthermore, incubation of HAoSMC with aldosterone led to enhanced EGF-induced ERK1/2 phosphorylation and an EGFR-dependent increase in media fibronectin. EGFR promoter reporter gene assay as well as chromatin immunoprecipitation data indicate that MR interacts with the EGFR promoter. With deletion constructs we gained evidence that this interaction takes place between the hMR and the EGFR promoter regions 316–163 (stronger activation site, EC50∼1.0 nM) and 163–1 (weaker activation site, EC50∼0.7 nM), which do not comprise canonical glucocorticoid response elements and are not activated by the human glucocorticoid receptor. The interactions require in part the NH2-terminal domains of MR. ELISA-based transcription factor DNA binding assay with in vitro synthesized hMR suggest direct binding to region 163–1. Our results indicate that aldosterone leads to enhanced EGFR expression via an interaction with the EGFR promoter, which is MR specific and could contribute to the aldosterone-induced increase in fibronectin abundance.
Neuroactive Steroids in Depression and Anxiety Disorders: Clinical Studies
Authors: Eser Daniela , Schüle Cornelius , Baghai Thomas C. , Romeo Elena , Rupprecht Rainer
Published: February 2007

Certain neuroactive steroids modulate ligand-gated ion channels via non-genomic mechanisms. Especially 3α-reduced pregnane steroids are potent positive allosteric modulators of the γ-aminobutyric acid type A (GABAA) receptor. During major depression, there is a disequilibrium of 3α-reduced neuroactive steroids, which is corrected by clinically effective pharmacological treatment. To investigate whether these alterations are a general principle of successful antidepressant treatment, we studied the impact of nonpharmacological treatment options on neuroactive steroid concentrations during major depression. Neither partial sleep deprivation, transcranial magnetic stimulation, nor electroconvulsive therapy affected neuroactive steroid levels irrespectively of the response to these treatments. These studies suggest that the changes in neuroactive steroid concentrations observed after antidepressant pharmacotherapy more likely reflect distinct pharmacological properties of antidepressants rather than the clinical response. In patients with panic disorder, changes in neuroactive steroid composition have been observed opposite to those seen in depression. However, during experimentally induced panic induction either with cholecystokinine-tetrapeptide or sodium lactate, there was a pronounced decline in the concentrations of 3α-reduced neuroactive steroids in patients with panic disorder, which might result in a decreased GABAergic tone. In contrast, no changes in neuroactive steroid concentrations could be observed in healthy controls with the exception of 3α,5α-tetrahydrodeoxycorticosterone. The modulation of GABAA receptors by neuroactive steroids might contribute to the pathophysiology of depression and anxiety disorders and might offer new targets for the development of novel anxiolytic compounds.
Genes and Pulmonary Arterial Hypertension
Authors: Sztrymf Benjamin , Yaïci Azzedine , Girerd Barbara , Humbert Marc
Published: February 2007

Familial pulmonary arterial hypertension (FPAH) was first described more than 50 years ago. Before the availability of modern genetic tools, studies of the genealogies demonstrated that these cases segregated as an autosomic dominant trait, with an incomplete penetrance and a genetic anticipation phenomenon by which age at onset of the disease is decreasing in the subsequent generations. Germline mutations in the gene coding for the bone morphogenetic protein receptor II (BMPR2) are present in more than 70% of FPAH and up to 26% of idiopathic, apparently sporadic cases (IPAH). Incomplete penetrance (around 20%) is a major pitfall because FPAH becomes ignored when the disease skips one or several generations. Genetic counseling is complex, with a significant number of BMPR2 mutation healthy carriers screened in some families. Incomplete penetrance puts them in the anxious situation of being potentially affected in the future by this devastating condition or to transmit this risk to their offspring. Nevertheless, genetic testing and counseling is about to become a standard in the management of PAH. Recent international guidelines on PAH state that genetic testing is recommended in FPAH and that IPAH patients have to be informed about the availability of such testing.
The Implementation of Guidelines and Prognosis among Patients with Acute Coronary Syndromes Is Influenced by Physicians’ Perception of Antecedent Physical and Cognitive Status
Authors: Porter Avital , Iakobishvili Zaza , Dictiar Rita , Behar Solomon , Hod Hanoch , Gottlieb Shmuel , Hammerman Haim , Zahger Doron , Hasdai David
Published: February 2007

Background/Aims: Physicians’ perception of antecedent physical/cognitive status may account for the suboptimal implementation of acute coronary syndrome (ACS) guidelines. Methods: In an ACS survey of all cardiac wards, physicians’ perception of antecedent physical/cognitive status was prospectively recorded and categorized as either normal, mildly impaired or significantly impaired. We examined the impact of antecedent status on the use of evidence-based medications and procedures and on mortality. Results: Of the 2,021 patients, 1,025 (51%) had ST elevation. Impaired antecedent physical/cognitive status was diagnosed in 417 patients (20.6%), more commonly among non-ST-elevation patients (26.2 vs. 15.2%). Patients with impaired physical/cognitive status, with or without ST elevation, had significantly worse baseline demographic and clinical characteristics. They less often received aspirin, clopidogrel, platelet glycoprotein IIb/IIIa receptor antagonists, statins and β-adrenergic blockers, and significantly less often underwent in-hospital catheterization and revascularization. Reperfusion treatment was given significantly less frequently to ST elevation patients with impaired status (63.0% for normal vs. 50.8% and 33.3% for mildly and significantly impaired status, respectively; p = 0.001). After adjustment for differences in baseline characteristics, impaired antecedent status remained independently associated with lower use of these therapies and higher mortality rates. Conclusions: ACS guideline implementation is significantly influenced by physicians’ perception of antecedent physical/cognitive status, and thus is a crucial parameter for understanding ACS management and outcomes.
Antimicrobial Activities of Some Tetrahydronaphthalene-Benzimidazole Derivatives
Authors: Ates-Alagoz Zeynep , Yildiz Sulhiye , Buyukbingol Erdem
Published: February 2007

Novel retinoid derivatives containing a benzimidazole moiety were synthesized and tested for their antimicrobial activity. Their antimicrobial activities against methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Candida krusei and Candida albicans were evaluated. While some of the compounds exhibited moderate activity against MRSA, S. aureus, E. faecalis, C. krusei and C. albicans, none of the compounds showed activity against E. coli and P. aeruginosa.
Use of Antidromic Evoked Potentials in Placement of Dorsal Cord Disc Electrodes
Authors: Yingling Charles D. , Hosobuchi Yoshio
Published: February 2007

Intraoperative recordings of somatosensory evoked potentials were made in 16 patients undergoing implantation of a dorsal cord stimulation system. Antidromic recordings, obtained by stimulating through the dorsal cord electrode placed in the epidural space and recording over peripheral nerves in the painful region of the body, had much higher signal-to-noise ratios and could be obtained with greater reliability than Standard orthodromic recordings. When the placement of the electrode was adjusted to obtain evoked responses in the painful region, paresthesias referred to that region were obtained in virtually every case. Use of this procedure allows implantation and internalization of the electrodes in a single procedure under general anesthesia, and reduces the necessity of subsequent revisions.
Influence of Long-Term Low Direct Current on Rat Ischiadic Nerves
Authors: Rosenkranz D. , Fenzl G. , Holle J. , Lack W. , Losert U. , Thoma H.
Published: February 2007

The effects of a low direct current on peripheral nerves and electrodes on the ischiadic nerve were investigated, and a constant direct current was applied for various time periods. Afterwards clinicophysiological tests and histological evaluations were performed. The muscles of 55 rats could be stimulated by external stimulation during the follow-up examinations, but 90% of all animals showed microscopically visible nerve tissue alterations which might have been caused by mechanical rather than electrolytic factors.
Transcutaneous Nerve Stimulation
Authors: Katims Jefferson J. , Long Donlin M. , Ng Lorenz K.Y.
Published: February 2007

The effects of transcutaneous electrical nerve stimulation (TNS) of a constant alternating current administered at various frequencies and waveforms to volunteer human subjects were investigated. The TNS was found to evoke noncutaneous subjective sensations in all the subjects. Only with a sinusoid waveform of TNS were distinct frequency ranges of the stimulation associated with specific noncutaneous subjective sensations. Our findings suggest that nervous tissue is capable of discriminating the waveform parameters of an electrical stimulus.
Gouda Frame Redesigned Specifically for Computed Tomographic Compatibility
Authors: Gouda Kasim I. , Freidberg Stephen R. , Baker Richard A. , Larsen Carl R. , Silverman Mark L.
Published: February 2007

The Gouda stereotactic frame has been redesigned for use with computed tomography. The patient is attached to the frame, is scanned, and is moved to the operating room for stereotactic biopsy. The Gouda frame permits accurate biopsy of otherwise inaccessible tumors of the brain.
Stereotactic Computed Tomographic-Guided Functional Neurosurgery Using the Redesigned Gouda Frame
Authors: Gouda Kasim I. , Freidberg Stephen R. , Fager Charles A. , Tarlov Edward C. , Baker Richard A. , Larsen Carl R. , Kott Stephen H.
Published: February 2007

The Gouda frame has been used to perform thalamotomy successfully. Computer-generated coordinates were used without the need of ventriculography.
Effect of Epidural Spinal Cord Stimulation on the Activity of Lateral Vestibular Nucleus Neurons in the Cat
Authors: Çuliç M. , Jeftinija S.
Published: February 2007

The activity of neurons in Deiters’ lateral vestibular nucleus was recorded in decerebrate cats before, during and after spinal cord stimulation. An almost equal number of units were inhibited and excited early during stimulation. Later during stimulation the majority of units was inhibited. Early after cessation of stimulation an ever larger number of units were inhibited to an even larger extent (for about 2 imp/s on the average). Later after stimulus cessation the predominant inhibitory effect could still be noted, as well as excitation in some units. The results could support the hypothesis that the inhibition of Deiters’ neurons during and for some time after epidural cord stimulation may play a part in the decrease of limb spasticity. The mechanism of inhibitory and excitatory unitary responses, side effects during stimulation and differences between the experimental model and human state are discussed.