bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modulation of a spinal locomotor network by metabotropic glutamate receptors
Authors: Chapman Rebecca J. , Sillar Keith T. 
Published: September 2007

AbstractWe have explored the potential involvement of the three main classes of metabotropic glutamate receptor in the modulation of a spinal locomotor network using tadpoles of the anuran amphibianXenopus laevis. Selective activation of group I receptors inXenopusembryos and young larvae using the general group I agonist DHPG [(S)‐3,5‐dihyroxyphenylglycine] significantly increased the frequency of swimming and the number of spontaneously occurring swimming episodes, as monitored by extracellular recordings from ventral roots. Group I receptor activation was without significant effect on the duration or amplitude of motor bursts, the duration of swimming episodes, or the head‐to‐tail delay in the propagation of swimming activity. Activation of either group II or group III receptors, however, following bath applications of the specific agonists APDC [(2R,4R)‐aminopyrrolidine‐2,4‐dicarboxylic acid] and L‐AP4 (l‐2‐amino‐4‐phosphonobutanoate), respectively, produced a net inhibitory effect on many of the parameters of fictive swimming at both developmental stages, including a reduction in swimming frequency and episode duration, along with a significant reduction in motor burst amplitude and duration in larval animals only. Applications of selective antagonists provide evidence for activation of all three groups during swimming. The group II and III antagonists EGLU (1‐ethyl‐2‐benzimidazolinone) and MAP4 [(S)‐2‐amino‐2‐methyl‐4‐phosphonobutanoate], respectively, increased, while group I antagonists, CPCCOEt and MPEP, decreased swim frequency. Our findings thus provide evidence for the presence and endogenous activation of three classes of metabotropic glutamate receptor which may function as an intrinsic modulatory control system during fictive swimming inXenopustadpoles.
Gaze pursuit, ‘attention pursuit’ and their effects on cortical activations
Authors: Ohlendorf S. , Kimmig H. , Glauche V. , Haller S. 
Published: September 2007

AbstractA moving object draws our attention to it and we can track the object with smooth pursuit eye movements (SPEM). Gaze and attention are usually directed to the same object during SPEM. In this study we investigated whether gaze and attention can be divided during pursuit. We explored the cortical control of ocular tracking and attentive tracking and the role of focused and divided attention. We presented a sinusoidally moving target for pursuit and simultaneously a stationary target for fixation. Gaze could be directed to the pursuit target and attention to the fixation target or vice versa, or gaze and attention were directed to the same (moving or stationary) target. We found that gaze (overt) and attentive (covert) pursuit similarly activated the cortical oculomotor network. Gaze pursuit showed higher activations than attentive pursuit. Activations, specific to the dissociation of attention from gaze and independent of eye movements, were found solely in the posterior parietal cortex. A cue indicating a forthcoming attention task activated large parts of the cortical SPEM network, as a kind of preparatory mechanism. We did not find any attention‐related regions outside the well‐known visuo‐oculomotor network. We conclude that attention control during gaze pursuit and gaze fixation occur within the cortical SPEM network, supporting the premotor theory of attention [Rizzolatti, G., Riggio, L., Dascola, I. & Umilta, C. (1987) Neuropsychologia, 25, 31–40].
Modulation of high‐frequency (600 Hz) somatosensory‐evoked potentials after rTMS of the primary sensory cortex
Authors: Restuccia Domenico , Ulivelli Monica , De Capua Alberto , Bartalini Sabina , Rossi Simone 
Published: September 2007

AbstractSomatosensory inputs to the primary sensory cortex (S1) after median nerve stimulation include temporally overlapping parallel processing, as reflected by standard low‐frequency somatosensory‐evoked potentials (LF‐SEPs) and high‐frequency SEPs (HF‐SEPs), the latter being more sensitive to arousal and to other rapid adaptive changes. Experimental data suggest that cortical HF‐SEPs are formed by two successive pre‐ and postsynaptic components, respectively, generated in the terminal part of thalamo‐cortical radiation (early burst) and in specialized neuronal pools within S1 (later burst).In eight healthy subjects, slow (1 Hz) or rapid (10 Hz) repetitive transcranial magnetic stimulations (rTMS), which are known to induce opposite changes on cortical excitability, applied on S1 did not modify LF‐SEPs, while HF‐SEPs showed a series of dissociate changes in the early and later high‐frequency burst, moreover occurring with a different time‐course. Slow rTMS caused an immediate and lasting decrease of the later burst activity, coupled with an immediate increase of the earlier part of the burst, suggesting that inhibition of cortical excitability triggered opposite, compensatory effects at subcortical levels; rapid rTMS induced a delayed increase of later HF‐SEPs, leaving unaltered the earlier subcortical burst.Findings causally demonstrate that LF‐ and HF‐SEPs reflect two distinct functional pathways for somatosensory input processing, and that early and late high‐frequency burst do actually reflect the activity of different generators, as suggested by experimental data. Possible underlying neurophysiological phenomena are discussed.
Entrepreneurial Academics: Developing Scientific Careers in Changing University Settings
Authors: Duberley Joanne , Cohen Laurie , Leeson Elspeth 
Published: September 2007

AbstractThis paper examines the impact of entrepreneurial initiatives within universities on scientific careers. Based on the career accounts of university‐based bioscientists involved in a government‐sponsored entrepreneurship training initiative, the paper explores the concept of academic entrepreneurialism. Three groups were identified in the data. First, academic entrepreneurs, who tended to be more experienced scientists and were now able to capitalise on their science. Second, those interested in technology transfer, who saw their career path taking them away from science, and finally a group of younger scientists who were trying to develop their career capital but were unsure what direction their career would take. The implications of these different groups for the management of universities and the development of knowledge are considered.
Institutional Diversity in Higher Education: a Cross‐National and Longitudinal Analysis
Authors: Huisman Jeroen , Meek Lynn , Wood Fiona 
Published: September 2007

AbstractThis paper contributes to the debate on institutional diversity in higher education systems by looking at the phenomenon from a comparative (cross‐national) and longitudinal perspective. Despite the attention to diversity in policy debates, surprisingly, only a limited amount of studies address methodological issues. In addition, the number of empirical studies on institutional diversity is low as well. Data on various Western higher education systems are used to illustrate developments in systems' diversity. Furthermore, these data are put in the context of current national (and supranational) policy debates, particularly the role of governments and markets, on maintaining or increasing diversity.
New and improved molecular sexing methods for museum bird specimens
Authors: BANTOCK TRISTAN M. , PRYS‐JONES ROBERT P. , LEE PATRICIA L. M. 
Published: September 2007

AbstractWe present two new avian molecular sexing techniques for nonpasserine and passerine birds (Neognathae), which are more suitable for use with museum specimens than earlier methods. The technique for nonpasserines is based on a new primer (M5) which, in combination with the existing P8 primer, targets a smaller amplicon in the CHD1 sex‐linked gene than previously. Primers targeting ATP5A1, an avian sex‐linked gene not previously used for sex identification, were developed for passerines. Comprehensive testing across species demonstrated that both primer pairs sex a range of different species within their respective taxonomic groups. Rigorous evaluation of each method within species showed that these permitted sexing of specimens dating from the 1850s. For corn bunting museum specimens, the ATP5A1 method sexed 98% of 63 samples (1857–1966). The M5/P8 CHD1 method was similarly successful, sexing 90% of 384 moorhen specimens from six different museum collections (1855–2001). In contrast, the original P2/P8 CHD1 sexing method only identified the sex of less than half of 111 museum moorhen samples. In addition to dried skin samples, these methods may be useful for other types of material that yield degraded or damaged DNA, and are hence potential new sexing tools for avian conservation genetics, population management and wildlife forensics.
Ten polymorphic STR loci in the cosmopolitan reef coral, Pocillopora damicornis
Authors: STARGER CRAIG J. , YEOH SEAN S. R. , DAI CHANG‐FENG , BAKER ANDREW C. , DESALLE ROB 
Published: September 2007

AbstractWe report the development of 10 polymorphic molecular markers containing short tandem repeats in the cosmopolitan reef‐building coral, Pocillopora damicornis, an important model species for coral health, physiology, ecology, and genetics. The availability of polymorphic DNA markers in P. damicornis can act as impetus for investigations into inheritance and population genetics, as well as novel investigations into host‐symbiont ecology and evolution. Coral bleaching and gene flow studies performed with these markers can have direct conservation implications.
Presbyopia and heat: changes associated with aging of the human lens suggest a functional role for the small heat shock protein, α‐crystallin, in maintaining lens flexibility
Authors: Heys Karl R. , Friedrich Michael G. , Truscott Roger J. W. 
Published: September 2007

SummaryPresbyopia, the inability to focus up close, affects everyone by age 50 and is the most common eye condition. It is thought to result from changes to the lens over time making it less flexible. We present evidence that presbyopia may be the result of age‐related changes to the proteins of the lens fibre cells. Specifically, we show that there is a progressive decrease in the concentration of the chaperone, α‐crystallin, in human lens nuclei with age, as it becomes incorporated into high molecular weight aggregates and insoluble protein. This is accompanied by a large increase in lens stiffness. Stiffness increases even more dramatically after middle age following the disappearance of free soluble α‐crystallin from the centre of the lens. These alterations in α‐crystallin and aggregated protein in human lenses can be reproduced simply by exposing intact pig lenses to elevated temperatures, for example, 50 °C. In this model system, the same protein changes are also associated with a progressive increase in lens stiffness. These data suggest a functional role for α‐crystallin in the human lens acting as a small heat shock protein and helping to maintain lens flexibility. Presbyopia may be the result of a loss of α‐crystallin coupled with progressive heat‐induced denaturation of structural proteins in the lens during the first five decades of life.
Is Sirt1 a miracle bullet for longevity?
Authors: Imai Shin‐ichiro 
Published: September 2007

SummaryThe Sir2 (silent information regulator 2) family of nicotinamide adenine dinucleotide‐dependent deacetylases has been implicated in the regulation of aging and longevity across a wide variety of organisms. Although controversial, Sir2 proteins have also been implicated as key mediators for the beneficial effects of caloric restriction (CR) on aging and longevity. In this issue, Bordone et al. report that transgenic mice in which the mammalian Sir2 ortholog Sirt1 is overexpressed mimic the physiological changes in response to CR. These findings have important implications for the development of CR mimetics and perhaps also for lifespan extension.
Non‐Surgical Salvage of Thrombosed Arterio‐Venous Fistulae: A Case Series and Review of the Literature
Authors: Moossavi Shahriar , Regan John D. , Pierson Eric D. , Kasey John M. , Tuttle Audrey B. , Vachharajani Tushar J. , Bettmann Michael A. , Russell Gregory B. , Freedman Barry I. 
Published: September 2007

AbstractAttempts to salvage thrombosed hemodialysis arterio‐venous fistulae (AVF) using interventional techniques are not universally performed. Patients often require temporary dialysis catheters pending creation of a new vascular access. We determined the long‐term outcome of interventional (non‐surgical) repair of completely thrombosed AVF in 49 consecutive accesses (22 radio‐cephalic, 1 radio‐basilic, 19 brachio‐cephalic, and 7 brachio‐basilic) referred for an intervention within 48 hours of thrombosis. Subjects were 65% male (32), with mean ± SD age 63.7 ± 13.5 years (range 33–91), 51% African‐American (25), 47% Caucasian (23) and 65% had diabetes (32). Overall, 96% (47/49) of thrombosed AVF were salvaged with complications observed in four cases (two extravasations of contrast; two radial artery emboli), with no serious long‐term sequelae. Interventional procedures included 34 venous angioplasties, 11 venous angioplasties with stenting and two combined venous and arterial angioplasties. The primary and secondary patency rates for all salvaged AVF were 50.5 ± 8.7%, 72.5 ± 7.8% at 1 year, and 43.3 ± 10%, 55.4 ± 12.7% at 2 years, respectively. The median estimate to first intervention after the declot procedure was 14.7 months. The median estimate for continued function exceeded 23.1 months. There was no significant statistical difference in the primary (p = 0.73) and secondary patency rates (p = 0.057) for forearm vs. upper arm AVF. We conclude that interventional repairs should routinely be employed to salvage newly thrombosed AVF. The vast majority of these individuals can avoid receiving dialysis catheters or placement of a new dialysis vascular access.
“Raynaud's Disease” in Migraineurs: One Entity or Two?
Authors: Kaiser Ronald S. 
Published: September 2007

SYNOPSISTwo cases are reported of patients who were diagnosed as having both migraine and Raynaud's disease. Because they were able to achieve effective control of both headaches and extremity temperature after undergoing a comprehensive approach‐utilizing medication, biofeedback, and psychotherapy‐it is suggested that both conditions are manifestations of the same disorder. It is recommended that a first step in approaching concurrent diagnoses of this type involve combined treatment as is often used in response to the singular diagnosis of migraine.
Reducing the risk of transfusion‐transmissible viral infection through blood donor selection: the Australian experience 2000 through 2006
Authors: Polizzotto Mark N. , Wood Erica M. , Ingham Helen , Keller Anthony J. ,   Australian Red Cross Blood Service Donor and Product Safety Team
Published: September 2007

BACKGROUND: Selection of voluntary donors who are at low risk of transfusion‐transmissible viral infection (TTVI) is central in maintaining the safety of the blood supply. Evaluation of its effectiveness and the dynamics of the process may offer opportunities to further improve transfusion safety.STUDY DESIGN AND METHODS: The impact of donor selection on prevalence of TTVI was analyzed in all allogeneic donations in Australia between July 2000 and June 2006 by interviewing donors found to have a TTVI. The presence and disclosure of infective risks was reassessed.RESULTS: A total of 6.3 million donations were tested; of these, 1449 (0.02%) were repeat‐reactive for a TTVI and were discarded. This comprised 605 (42%) positive for the presence of hepatitis B, 818 (56%) positive for the presence of hepatitis C, 18 (1%) positive for the presence of human immunodeficiency virus, and 20 (1%) positive for the presence of human T‐cell lymphotropic virus‐I and/or ‐II (HTLV‐I/II). This prevalence was 50 to 350 times lower than in the Australian population. In 1158 cases (80%), an infective risk was identified; 509 donors (44%) had more than one. The most common identified were country of birth and parental ethnicity (n = 682, 26% of risks), tattoos and/or piercings (n = 448, 18%), and intravenous drug use (n = 302, 12%). In 302 cases (21%) disclosure at predonation screening would have resulted in deferral. Factors influencing nondisclosure included temporal remoteness and perceptions that laboratory testing rendered disclosure unnecessary.CONCLUSION: These findings affirm the effectiveness of current stringent donor selection criteria in reducing the residual risk of TTVI. Ongoing donor education regarding the importance of risk disclosure is required.
Understanding the meaning of permanent deferral for blood donors
Authors: Whittaker Susan , Carter Nancy , Arnold Emmy , Shehata Nadine , Webert Kathryn E. , DiStefano Lanis , Heddle Nancy M. 
Published: September 2007

BACKGROUND:To ensure the safety of the blood supply, it is necessary to permanently defer blood donors with a repeat‐reactive transmissible disease test result. The purpose of this study was to explore the permanent deferral experience from the donor's perspective.STUDY DESIGN AND METHODS:A qualitative study was conducted with donors from two Canadian blood centers who received written notice of permanent deferral in six deferral categories: human immunodeficiency virus‐1 and/or ‐2 and hepatitis C virus and/or hepatitis B virus (negative, indeterminate, or positive). Telephone interviews were conducted with a semistructured questionnaire. Interview transcripts were coded and central themes were identified. The data were then modeled to illustrate the relationships between the themes.RESULTS:Twenty‐eight permanently deferred donors were interviewed and described a variety of negative emotional and behavioral responses including confusion, shock, disbelief, panic, fear, anger, stigmatization, and loss. A conceptual model was developed illustrating the phases that a deferred donor goes through (identifying as a healthy donor, receiving notification, experiencing emotional and behavioral reactions, trying to make sense of what happened, and taking action) as they travel along the path to becoming either a “reconciled” or “not reconciled” permanently deferred donor. Participants offered constructive suggestions for modifying the notification process including revising the letter, providing follow‐up, and educating family physicians.CONCLUSIONS:To our knowledge, this is the first study to use qualitative research methodology to explore the experience of permanent blood donor deferral. More studies are needed to validate and expand this preliminary conceptual model.
A systematic review and survey of the management of unexpected neonatal alloimmune thrombocytopenia
Authors: Bassler Dirk , Greinacher Andreas , Okascharoen Chusak , Klenner Anne , Ditomasso Juliana , Kiefel Volker , Chan Anthony , Paes Bosco 
Published: September 2007

BACKGROUND:Unexpected neonatal alloimmune thrombocytopenia (NAIT) may have devastating consequences and its management is challenging. To design future trials, evidence from the literature and existing best practice need review.STUDY DESIGN AND METHODS:This study was a cross‐sectional survey of neonatal units in Germany and Canada to determine management strategies of NAIT and a systematic search for randomized controlled trials (RCTs).RESULTS:Management of NAIT differs substantially between countries with regard to platelet (PLT) thresholds for screening, initiation of therapy, and treatment. Seventy‐seven percent of Canadian physicians versus 68 percent of German physicians screen preterm and term infants, at a PLT threshold of 30 × 109to 100 × 109per L. In preterm infants, 60 percent of Canadian neonatologists commence treatment at a PLT count of between 30 × 109and 50 × 109per L. In Germany 32 percent of the physicians start treatment at this level and 25 percent use a threshold of between 10 × 109and 20 × 109per L. In term infants, 6 percent of the Canadian physicians and 16 percent of the German physicians use even lower treatment triggers of between 5 × 109and 10 × 109per L. In the presence of bleeding, 61 percent of German physicians await the arrival of antigen‐negative PLTs, while 64 percent of Canadian neonatologists prefer intravenous immunoglobulin or random‐donor PLTs (81%). Maternal PLTs are utilized by 31 percent of physicians in both countries. No RCTs were identified.CONCLUSION:In the absence of RCTs, management of unexpected NAIT differs between countries. Clinicians and transfusion services may use the results of our study to develop collaborative protocols, redefine preferred hospitalwide strategies, and design future controlled trials.
Prediction of Atrial Fibrillation with Atrial Late Potentials and Pathological Chemoreflexsensitivity
Authors: BUDEUS MARCO , HENNERSDORF MARCUS , REINSCH NICO , WIENEKE HEINRICH , SACK STEFAN , ERBEL RAIMUND 
Published: September 2007

Background:

Atrial fibrillation (AF) is a very common arrhythmia that often causes the serious complication of a stroke.
Object:

The aim was to evaluate the utility of pathological chemoreflexsensitivity (PCHRS) and atrial late potentials (ALP) to predict AF in follow‐up.
Methods:

We investigated a prospective study on the basis of our observation about a PCHRS and ALP in paroxysmal AF. The PCHRS was predefined as a chemoreflexsensitivity below 3.0 ms/mmHg and ALP were predefined as a filtered P‐wave duration ≥120 ms and a root mean square voltage of the last 20 ms of the P‐wave ≤3.5 μV. A P‐wave triggered P‐wave signal averaged electrocardiograph (ECG) and chemoreflexsensitivity was performed on 250 consecutive patients who were divided into four groups. Group I consisted of patients with ALP and PCHRS, patients of group II had only ALP, a PCHRS was only present in group III, and patients of group IV had neither ALP nor PCHRS.
Results:

During the mean follow‐up of 37.8 months AF was observed in 10 patients (4%). The patients of the four groups were similar according to clinical baseline characteristics. The incidence of AF was higher in group I (18% of patients) than in group II (6% of patients, P = 0.229) and significantly higher than in group III (3% of patients, P = 0.034) or group IV (1% of patients, P < 0.0001). Patients with ALP and PCHRS showed a 33‐fold risk (P < 0.001) for the onset AF.
Conclusions:

The results of our study suggest that the probability of AF could be predicted with a P‐wave signal averaged ECG and an analysis of chemoreflexsensitivity. The predictive power of the combination of ALP and PCHRS seemed not high enough for risk stratification.
Dialysis quality and quantity: How much and how often?
Authors: SPALDING Elaine , FARRINGTON Ken 
Published: September 2007

AbstractHemodialysis is accepted as standard therapy for end‐stage renal failure but despite four decades of experience the morbidity and mortality associated with the treatment remains unacceptably high. Quality of dialysis is traditionally measured with reference to urea clearance but it is becoming increasingly apparent that other solutes across the range of molecular size are also important. More prolonged or more frequent therapy may improve dialysis delivery and enhance survival in patients with end‐stage renal disease.