bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient Estimation of Auto-Regression Parameters and Innovation Distributions for Semiparametric Integer-Valued AR(p) Models
Authors: Drost Feike C. , Van Den Akker Ramon , Werker Bas J. M.
Published: April 2009

Integer-valued auto-regressive (INAR) processes have been introduced to model non-negative integer-valued phenomena that evolve over time. The distribution of an INAR(p) process is essentially described by two parameters: a vector of auto-regression coefficients and a probability distribution on the non-negative integers, called an immigration or innovation distribution. Traditionally, parametric models are considered where the innovation distribution is assumed to belong to a parametric family. The paper instead considers a more realistic semiparametric INAR(p) model where there are essentially no restrictions on the innovation distribution. We provide an (semiparametrically) efficient estimator of both the auto-regression parameters and the innovation distribution.
Prevalence of psychopathology in childhood epilepsy: categorical and dimensional measures
Authors: DUNN DAVID W , AUSTIN JOAN K , PERKINS SUSAN M
Published: April 2009

Few studies have utilized both categorical and dimensional measures of psychopathology in children with epilepsy. We evaluated 173 children (88 males, 85 females; mean age 11.7y [SD 1.8]; range 9−14y) who had epilepsy (generalized 36%, partial 61%) for at least 6 months. The primary caregiver completed a dimensional measure, the Child Behavior Checklist (CBCL), and a categorical measure, either the Child Symptom Inventory (CSI) or the Adolescent Symptom Inventory (ASI). Correlation coefficients were computed between the CBCL scores and CSI/ASI symptom scores. For all children, diagnostic risk was higher than norms on CSI/ASI for attention‐deficit−hyperactivity disorder (ADHD) inattentive type, ADHD combined type, oppositional defiant disorder, and dysthymic disorder. For children between 9 and 12 years, elevated scores were found on CBCL, total, internalizing, and attention problems, and on CSI, diagnostic risk for conduct disorder and Asperger syndrome. For children of 13 and 14 years, ASI diagnostic risk was higher for specific phobia, obsessions, posttraumatic stress disorder, motor tics, antisocial personality, panic attack, somatization disorder, and enuresis. CBCL and symptom scores on the CSI/ASI were significantly correlated. The conclusion was that children with epilepsy have high rates of behavioral difficulties on both dimensional and categorical measures. Concurrent validity for the CSI/ASI was supported.
Children at risk for developmental coordination disorder: judgement of changes in action capabilities
Authors: JOHNSON DANIEL C , WADE MICHAEL G
Published: April 2009

In three separate manipulations, a group of children at risk for developmental coordination disorder (DCD; five males, seven females; mean age 11y 6mo [SD 6.8mo]who were at or below the 15th centile on the Movement ABC) and a group of typically developing children (TDC; seven males, five females; mean age 11y 3mo [SD 6.8mo]) judged the limit of their standing horizontal reach (HRmax) under two conditions in which actual HRmax differed. The manipulations were: (1) one‐hand versus two‐hand reach; and (2) standard versus short effective foot‐length; and (3) rigid versus compliant support surface. For the foot‐length and support surface manipulations (but not for the hand manipulation), children correctly judged that their actual HRmax differed in the two conditions (p<.05). On all three manipulations, TDC made significantly larger adjustments in their judgements than did children at risk for DCD (p<0.05). The TDC group adjusted their judgements in the appropriate direction on all three manipulations, whereas the DCD group adjusted in the appropriate direction for the foot‐length manipulation only. The results suggest that children at risk for DCD are less adept at detecting changes in the limits of their action capabilities.
Exogenous melatonin for sleep problems in individuals with intellectual disability: a meta‐analysis
Authors: BRAAM WIEBE , SMITS MARCEL G , DIDDEN ROBERT , KORZILIUS HUBERT , GEIJLSWIJK INGEBORG M VAN , CURFS LEOPOLD M G
Published: April 2009

Recent meta‐analyses on melatonin has raised doubts as to whether melatonin is effective in treating sleep problems in people without intellectual disabilities. This is in contrast to results of several trials on melatonin in treating sleep problems in individuals with intellectual disabilities. To investigate the efficacy of melatonin in treating sleep problems in individuals with intellectual disabilities, we performed a meta‐analysis of placebo‐controlled randomized trials of melatonin in individuals with intellectual disabilities and sleep problems. Data were selected from articles published on PubMed, Medline, and Embase between January 1990 and July 2008. We examined the influence of melatonin on sleep latency, total sleep time, and number of wakes per night. Quality of trials was assessed using the Downs and Black checklist. Nine studies (including a total of 183 individuals with intellectual disabilities) showed that melatonin treatment decreased sleep latency by a mean of 34 minutes (p<0.001), increased total sleep time by a mean of 50 minutes (p<0.001), and significantly decreased the number of wakes per night (p<0.05). Melatonin decreases sleep latency and number of wakes per night, and increases total sleep time in individuals with intellectual disabilities.
Unmasking emotion: Exposure duration and emotional engagement
Authors: Codispoti Maurizio , Mazzetti Michela , Bradley Margaret M.
Published: April 2009

Effects of exposure duration on emotional reactivity were investigated in two experiments that parametrically varied the duration of exposure to affective pictures from 25–6000 ms in the presence or absence of a visual mask. Evaluative, facial, autonomic, and cortical responses were measured. Results demonstrated that, in the absence of a visual mask (Experiment 1), emotional content modulated evaluative ratings, cortical, autonomic, and facial changes even with very brief exposures, and there was little evidence that emotional engagement increased with longer exposure. When information persistence was reduced by a visual mask (Experiment 2), differences as a function of hedonic content were absent for all measures when exposure duration was 25 ms but statistically reliable when exposure duration was 80 ms. Between 25–80 ms, individual differences in discriminability were critical in observing affective reactions to masked pictures.
Protective effect of interval exercise on psychophysiological stress reactivity in children
Authors: Roemmich James N. , Lambiase Maya , Salvy Sarah J. , Horvath Peter J.
Published: April 2009

Two studies determined whether interval exercise reduces children's stress reactivity. For Experiment 1 children completed interval exercise (n=14) or watched TV (n=14) for 25 min. After 20 min rest children completed a speech task. Speech‐induced diastolic blood pressure (DBP) reactivity was dampened in the exercise group (p<.05). For Experiment 2 children (n=22) completed interval exercise‐speech and TV‐speech conditions on separate days. Physical activity was assessed by accelerometry and aerobic fitness estimated by submaximal exercise. DBP, systolic BP, and heart rate (HR) reactivity to the speech stressor were dampened (p<.05) after exercise compared to TV watching. Fitness was positively associated with HR reactivity. Interval exercise that mimics usual patterns of physically active play dampens cardiovascular reactivity to interpersonal stress.
The application of subliminal priming in lie detection: Scenario for identification of members of a terrorist ring
Authors: Lui Ming , Rosenfeld J. Peter
Published: April 2009

We studied a lie detection protocol immune to countermeasures. The 4 stimulus conditions were (1 and 2) supraliminal acquaintance name primed by subliminal acquaintance name (A‐A) versus subliminal nonacquaintance name (N‐A) and (3 and 4) supraliminal nonacquaintance name primed by subliminal acquaintance name (A‐N) versus subliminal nonacquaintance name (N‐N). In Experiment 1 and replication, principal components analysis‐derived event‐related potential components revealed significant differences between dishonestly answered supraliminal acquaintance conditions with differing primes (A‐A vs. N‐A). In Experiment 2 subjects were required to lie in A‐N and N‐N conditions, in contrast to Experiment 1, in which subjects lied in A‐A and N‐A conditions. No significant effects were found. In Experiment 3, the lying task was removed and no significant differences were found. We conclude that subliminal primes modulate ERPs in conditions with supraliminal acquaintance name when the task involves lying.
Genetic and environmental influences on frontal EEG asymmetry and alpha power in 9–10‐year‐old twins
Authors: Gao Yu , Tuvblad Catherine , Raine Adrian , Lozano Dora I. , Baker Laura A.
Published: April 2009

Modest genetic influences on frontal EEG asymmetry have been found in adults, but little is known about its genetic origins in children. Resting frontal asymmetry and alpha power were examined in 951 9–10‐year‐old twins. Results showed that in both males and females: (1) a modest but significant amount of variance in frontal asymmetry was accounted for by genetic factors (11–28%) with the remainder accounted for by non‐shared environmental influences, and (2) alpha power were highly heritable, with 71–85% of the variance accounted for by genetic factors. Results suggest that the genetic architecture of frontal asymmetry and alpha power in late childhood are similar to that in adulthood and that the high non‐shared environmental influences on frontal asymmetry may reflect environmentally influenced individual differences in the maturation of frontal cortex as well as state‐dependent influences on specific measurements.
A simple classification tool for single‐trial analysis of ERP components
Authors: Bandt Christoph , Weymar Mathias , Samaga Daniel , Hamm Alfons O.
Published: April 2009

Event‐related potentials (ERPs) were recorded by measuring a dense sensor EEG from eight healthy volunteers in a visual oddball experiment. Single trials were analyzed with an extremely simple high‐dimensional version of discriminant analysis. The question was how many of the target trials contribute to the average P3, and to test whether other components in the ERP are sensitive to discriminate between target and non‐target trials. One common classification rule for all participants expressing the P3 component correctly classified 88% of the ERPs of all subjects in response to a target or non‐target trial. For four of the eight participants, there were strong differences in an early ERP component over the occipital recording sites. Their individual classification rules, obtained from the training data in the time interval up to 200 ms, correctly classified 85% of the trials of the test data.
Determining the effects of habitat management and climate on the population trends of a declining steppe bird
Authors: DELGADO MARÍA PAULA , MORALES MANUEL B. , TRABA JUAN , GARCIA DE LA MORENA ELADIO L.
Published: April 2009

The Little Bustard Tetrax tetrax is one of the most threatened steppe bird species in Europe, due mainly to agricultural intensification. Despite the relative importance of the Iberian population (approximately 50% of the global population) little is known about its dynamics and trends, especially in core distribution areas. This study evaluates the influences of meteorological factors and land management on the oscillations and medium‐term trends of two Little Bustard populations in Central Spain. During 2001–2007, surveys of breeding male and female Little Bustards were carried out in two central Spanish locations: Valdetorres, in Special Protection Area (SPA) no. 139 (1600 ha), and Campo Real, in Important Bird Area (IBA) no. 075 (1150 ha). Densities were 3.3–4.0 and 1.1–2.1 males/km2 in Campo Real, and 1.8–2.2 and 0.6–1.3 females/km2 in Valdetorres. The sex ratio was biased towards males in both cases. Both populations declined during 2001–2007, especially in Valdetorres (60%). Variation in habitat composition did not explain variation in the numbers of males. Both populations were influenced by total precipitation in the preceding October–May period. Results suggest that the Little Bustard may be sensitive to future climate trends in Europe. Finally, different simulated demographic scenarios suggest that low female survival and productivity may be the immediate cause of the decline in Little Bustard populations, which is consistent with their sensitivity to climatic conditions.
The Impact of Governmental Guidance on the Time Taken to Receive a Prescription for Medication for ADHD in England
Authors: Foreman David M.
Published: April 2009

The National Health Service in England has deployed guidance from the National Institute of Clinical Excellence (NICE) to assist practitioners in the diagnosis and treatment of Attention Deficit Hyperactivity Disorder (ADHD) but, though the number of prescriptions has risen since its introduction, the impact of the guidance on prescribing practice has not been studied. Clinic records of all open ADHD cases (296) in three English Child and Adolescent Mental Health Services were examined. The time from referral to either prescription or data collection was extracted for a survival analysis. It was hypothesised that NICE guidance, clinic, patient and referral characteristics would all influence the speed and likelihood of prescription. Following the introduction of NICE guidance, the median time to start prescribing medication fell from 1262 to 526 days: the minimum realistic time to complete a routine assessment was approximately 70 days. Overall, 70% were prescribed medication. Most of the wait was after face‐to‐face appointments at the clinic had been initiated. Waiting times differed between clinics and shorter waits were likely for older children and those referred from an educational source. While the introduction of NICE guidance has increased the rate of prescription, the time taken before prescription suggests that the tendency in England is still to postpone treatment by medication. The reasons for this require further research.
THE LOWER CAMBRIAN EODISCOID TRILOBITECALODISCUS LOBATUSFROM SWEDEN: MORPHOLOGY, ONTOGENY AND DISTRIBUTION
Authors: CEDERSTRÖM PETER , AHLBERG PER , CLARKSON EUAN N. K. , NILSSON CARIN H. , AXHEIMER NIKLAS
Published: April 2009

Abstract: Several thousand disarticulated remains together with a few complete enrolled specimens of the lower Cambrian eodiscoid trilobiteCalodiscus lobatus(Hall, 1847) have been collected at two outcrop areas in Sweden. The material reveals new details of morphology and morphogenesis during ontogenetic development. Size‐frequency analyses show that the material from the Fånån rivulet in Jämtland, central Sweden, represents a natural population dominated by juveniles, whereas the material from Gislövshammar in Scania, southern Sweden, has been sorted during postmortem transport. Three stages of protaspid development can be traced and defined as well as all subsequent ontogenetic stages for the cephalon, hypostome and pygidium. The early meraspid pygidium has a pronounced larval notch, which persists, though becoming progressively less distinct in later meraspides. The number of axial rings in the transitory pygidium increases throughout meraspid development until a third and final thoracic segment is liberated. During ontogeny the articulating half‐rings are strongly developed, and both meraspides and holaspides were capable of full sphaeroidal enrollment and outstretched postures. The hypostome undergoes some dramatic modifications; in M0 the anterior margin is axe‐shaped, by M1 the area of attachment greatly decreases and the hypostome becomes more elongated and pear‐shaped, before attaining its adult form, which has an overall resemblance to that of polymerid trilobites. During ontogeny, the hypostome changes from a conterminant attachment to a natant condition, thereby mirroring hypostomal evolution within trilobites generally. The morphology, ontogeny, enrollment, hypostomal development and the presence of calcified protaspides suggest polymerid rather than agnostoid affinities of the eodiscoids.
AN ORDOVICIAN LOBOPODIAN FROM THE SOOM SHALE LAGERSTÄTTE, SOUTH AFRICA
Authors: WHITTLE ROWAN J. , GABBOTT SARAH E. , ALDRIDGE RICHARD J. , THERON JOHANNES
Published: April 2009

Abstract:  The first lobopodian known from the Ordovician is described from the Soom Shale Lagerstätte, South Africa. The organism shows features homologous to Palaeozoic marine lobopodians described from the Middle Cambrian Burgess Shale, the Lower Cambrian Chengjiang biota, the Lower Cambrian Sirius Passet Lagerstätte and the Lower Cambrian of the Baltic. The discovery provides a link between marine Cambrian lobopodians and younger forms from the Silurian and Carboniferous. The new fossil preserves an annulated trunk, lobopods with clear annulations, and curved claws. It represents a rare record of a benthic organism from the Soom Shale, and demonstrates intermittent water oxygenation during the deposition of the unit.
Ezetimibe – new anti‐atherogenic properties?
Authors: Tomkin Gerald H
Published: April 2009

Ezetimibe, a Niemann Pick C1‐like1 inhibitor, inhibits cholesterol absorption. The drug has been shown to affect lipid raft function in monocytes and therefore may inhibit lipid accumulation in the atheromatous plaque with a mechanism that is unrelated to its effect in reducing cholesterol absorption. In this issue of the British journal of pharmacology, Gómez‐Garre et al. demonstrate that ezetimibe and simvastatin both have a beneficial effect on the atheromatous plaque, which may be due to their effect on both monocyte/macrophage function and reduction in nuclear factor‐κB activity. Whether these results in a rabbit model of atherosclerosis can be translated into human atherosclerosis awaits further studies.
Biochemical and behavioural characterization of EMPA, a novel high‐affinity, selective antagonist for the OX2 receptor
Authors: Malherbe P , Borroni E , Gobbi L , Knust H , Nettekoven M , Pinard E , Roche O , Rogers‐Evans M , Wettstein JG , Moreau J‐L
Published: April 2009

Background and purpose:  The OX2 receptor is a G‐protein‐coupled receptor that is abundantly found in the tuberomammillary nucleus, an important site for the regulation of the sleep‐wake state. Herein, we describe the in vitro and in vivo properties of a selective OX2 receptor antagonist, N‐ethyl‐2‐[(6‐methoxy‐pyridin‐3‐yl)‐(toluene‐2‐sulphonyl)‐amino]‐N‐pyridin‐3‐ylmethyl‐acetamide (EMPA).

Experimental approach:  The affinity of [3H]EMPA was assessed in membranes from HEK293‐hOX2‐cells using saturation and binding kinetics. The antagonist properties of EMPA were determined by Schild analysis using the orexin‐A‐ or orexin‐B‐induced accumulation of [3H]inositol phosphates (IP). Quantitative autoradiography was used to determine the distribution and abundance of OX2 receptors in rat brain. The in vivo activity of EMPA was assessed by reversal of [Ala11,D‐Leu15]orexin‐B‐induced hyperlocomotion during the resting phase in mice and the reduction of spontaneous locomotor activity (LMA) during the active phase in rats.

Key results:  [3H]EMPA bound to human and rat OX2‐HEK293 membranes with KD values of 1.1 and 1.4 nmol·L−1 respectively. EMPA competitively antagonized orexin‐A‐ and orexin‐B‐evoked accumulation of [3H]IP at hOX2 receptors with pA2 values of 8.6 and 8.8 respectively. Autoradiography of rat brain confirmed the selectivity of [3H]EMPA for OX2 receptors. EMPA significantly reversed [Ala11,D‐Leu15]orexin‐B‐induced hyperlocomotion dose‐dependently during the resting phase in mice. EMPA, injected i.p. in rats during the active phase, reduced LMA dose‐dependently. EMPA did not impair performance of rats in the rotarod procedure.

Conclusions and implications:  EMPA is a high‐affinity, reversible and selective OX2 receptor antagonist, active in vivo, which should prove useful for analysis of OX2 receptor function.
3D information extraction from laser point clouds covering complex road junctions
Authors: Oude Elberink Sander J. , Vosselman George
Published: April 2009

An automated method for 3D modelling of complex highway interchanges is presented. Laser data and 2D topographic map data have been combined in an innovative 3D reconstruction procedure. Complex situations as shown in this paper demand knowledge to guide the automatic reconstruction. This knowledge has been used in the fusion procedure to constrain the topological and geometrical properties of the reconstructed 3D model. These additions are needed to take care of the lack of data in occluded areas. Laser data has been segmented and filtered before it is fused with map data. In the surface‐growing algorithm combining map and laser points, the laser data is assigned to the corresponding road element. Although results are shown using two specific data sources, the algorithm is designed to be capable of dealing with any polygon‐based topographic map and any aerial laser scanner data‐set.
A photogrammetric application in virtual sport training
Authors: Chong Albert K. , Croft Hayden G.
Published: April 2009

The paper discusses an application of close range photogrammetry for the development of a virtual training system for rugby football, and the use of the technique for the evaluation of rugby players’ performance. NuView, a stereo‐imaging device, and a digital high‐definition video (HDV) camera were used to capture stereoscopic video footage of players during field training. The left view and the right view were colour‐tinted cyan and red, respectively. The tinted stereo (anaglyph) views were projected onto a white screen, and players were instructed to practise ball‐throwing at the screen. A custom‐built laser device (TAM) measured the accuracy of the virtual throws. In addition, a photogrammetric system was used to track the movement of body segments, for example, the angle of shoulder orientation and the trunk flexion of the thrower. The measurements determined the parameters needed for an accurate throw and these parameters would be used in the training of new players. The study shows statistically significant differences in the values of these parameters between experienced and inexperienced players.
Superoxide anions and hydrogen peroxide inhibit proliferation of activated rat stellate cells and induce different modes of cell death
Authors: Dunning Sandra , Hannivoort Rebekka A. , De Boer Jan Freark , Buist‐Homan Manon , Faber Klaas Nico , Moshage Han
Published: April 2009

Background: In chronic liver injury, hepatic stellate cells (HSCs) proliferate and produce excessive amounts of connective tissue causing liver fibrosis and cirrhosis. Oxidative stress has been implicated as a driving force of HSC activation and proliferation, although contradictory results have been described.

Aim: To determine the effects of oxidative stress on activated HSC proliferation, survival and signalling pathways.

Methods: Serum‐starved culture‐activated rat HSCs were exposed to the superoxide anion donor menadione (5–25 μmol/L) or hydrogen peroxide (0.2–5 mmol/L). Haem oxygenase‐1 mRNA expression, glutathione status, cell death, phosphorylation of mitogen‐activated protein (MAP) kinases and proliferation were investigated.

Results: Menadione induced apoptosis in a dose‐ and time‐dependent, but caspase‐independent manner. Hydrogen peroxide induced necrosis only at extremely high concentrations. Both menadione and hydrogen peroxide activated Jun N‐terminal kinase (JNK) and p38. Hydrogen peroxide also activated extracellular signal‐regulated protein. Menadione, but not hydrogen peroxide, reduced cellular glutathione levels. Inhibition of JNK or supplementation of glutathione reduced menadione‐induced apoptosis. Non‐toxic concentrations of menadione or hydrogen peroxide inhibited platelet‐derived growth factor‐ or/and serum‐induced proliferation.

Conclusion: Reactive oxygen species (ROS) inhibit HSC proliferation and promote HSC cell death in vitro. Different ROS induce different modes of cell death. Superoxide anion‐induced HSC apoptosis is dependent on JNK activation and glutathione status.
Outcomes of transjugular intrahepatic portosystemic shunt through the left branch vs. the right branch of the portal vein in advanced cirrhosis: a randomized trial
Authors: Chen Lei , Xiao Tianli , Chen Wensheng , Long Qingling , Li Rongjun , Fang Dianchun , Wang Rongquan
Published: April 2009

Background/Aims: The transjugular intrahepatic portosystemic shunt (TIPS) is technically divided into TIPS through the left branch of the portal vein (TIPS‐LBPV) and TIPS through the right branch of the portal vein (TIPS‐RBPV). In order to compare their advantages and disadvantages, this randomized, controlled trial was designed to investigate their outcomes in advanced cirrhotic patients.

Methods: Seventy‐two patients were randomly placed into TIPS‐LBPV (36 patients) and TIPS‐RBPV (36 patients, with four failures) groups, and they were prospectively followed for 2 years after TIPS implantation.

Results: Patients who underwent the two different kinds of TIPS were balanced during recruitment for this study. The incidences of overall encephalopathy and de novo encephalopathy in the TIPS‐LBPV group were significantly lower than that of the TIPS‐RBPV group during follow‐up (P=0.036 and 0.012 respectively). The incidences of rebleeding or re‐intervention and improvement of ascites were similar between groups (P>0.05). Patients undergoing TIPS‐RBPV required more rehospitalization and incurred more costs than those who underwent TIPS‐LBPV (P=0.030 and 0.039 respectively). There was no significant difference between the two groups in survival based on a survival curve constructed according to the Kaplan–Meier method (P>0.05).

Conclusion: Patients undergoing TIPS‐LBPV had a lower incidence of encephalopathy, less rehospitalization and lower costs after TIPS implantation compared with patients undergoing TIPS‐RBPV.
Habitat Fragmentation and Species Loss across Three Interacting Trophic Levels: Effects of Life‐History and Food‐Web Traits
Authors: CAGNOLO LUCIANO , VALLADARES GRACIELA , SALVO ADRIANA , CABIDO MARCELO , ZAK MARCELO
Published: April 2009

Abstract: Not all species are likely to be equally affected by habitat fragmentation; thus, we evaluated the effects of size of forest remnants on trophically linked communities of plants, leaf‐mining insects, and their parasitoids. We explored the possibility of differential vulnerability to habitat area reduction in relation to species‐specific and food‐web traits by comparing species–area regression slopes. Moreover, we searched for a synergistic effect of these traits and of trophic level. We collected mined leaves and recorded plant, leaf miner, and parasitoid species interactions in five 100‐m2transects in 19 Chaco Serrano woodland remnants in central Argentina. Species were classified into extreme categories according to body size, natural abundance, trophic breadth, and trophic level.Species–area slopes differed between groups with extreme values of natural abundance or trophic specialization. Nevertheless, synergistic effects of life‐history and food‐web traits were only found for trophic level and trophic breadth: area‐related species loss was highest for specialist parasitoids. It has been suggested that species position within interaction webs could determine their vulnerability to extinction. Our results provide evidence that food‐web parameters, such as trophic level and trophic breadth, affect species sensitivity to habitat fragmentation.
Fellows’ Forum: Laparoscopy in the Early Diagnosis and Management of Sclerosing Encapsulating Peritonitis
Authors: Kropp Jeffrey , Sinsakul Marvin , Butsch John , Rodby Roger
Published: April 2009

Sclerosing encapsulating peritonitis (SEP) is a rare and dreaded complication that can occur in patients undergoing peritoneal dialysis (PD). Although risk factors have been identified, the diagnosis is difficult and is usually made late in the disease after extensive fibrosis of the peritoneal membrane has occurred, at which point therapy is often fruitless. The high mortality rate of SEP is due to complications resulting from recurrent bowel obstruction, malnutrition, and sepsis. We report three patients with signs and symptoms suggestive of SEP all of whom had normal abdominal CT scans. Nevertheless, each patient underwent diagnostic laparoscopy, which confirmed the clinical suspicion of SEP. In each case, the diagnosis was made before extensive peritoneal fibrosis had occurred allowing therapeutic intervention at an early stage. All three patients subsequently became asymptomatic and thrived. This clinical improvement was supported by the lack of progression to overt peritoneal fibrosis on repeat laparoscopy. We conclude that a high index of suspicion in conjunction with a low threshold for diagnostic laparoscopy may be an effective strategy to establish an early diagnosis and treatment regimen for SEP. Additionally, repeat laparoscopy can be used to guide the length of therapy. These interventions may ultimately improve the long‐term morbidity and mortality of SEP.
Editorial: Aminoglycosides in Hemodialysis Patients: Is the Current Practice of Post Dialysis Dosing Appropriate?
Authors: O’Shea Stacey , Duffull Stephen , Johnson David W.
Published: April 2009

Aminoglycosides have been widely used in end‐stage renal failure patients for the treatment of infections caused by gram‐negative bacilli and Staphylococcus aureus. Traditionally, these agents are administered post dialysis to avoid premature dialytic clearance, although no studies have been performed to confirm that this dosing strategy represents the optimal treatment regimen. In recent years, a more complete understanding of the pharmacokinetics–pharmacodynamics of aminoglycosides has led to a global change in clinical practice from multiple to once‐daily dosing in patients with normal renal function with the aim of providing intermittent pulses to maximize the peak concentration relative to overall drug exposure. These same considerations strongly support administration of aminoglycosides before, rather than after, hemodialysis. This study will review the key pharmacokinetic/pharmacodynamic considerations in aminoglycoside dosing, the relationship between serum aminoglycoside concentrations and efficacy/toxicity, the influence of renal function and hemodialysis on aminoglycoside pharmacokinetics/pharmacodynamics, and the mounting population pharmacokinetic and clinical study evidence supporting a paradigm shift in aminoglycoside dosing from post dialysis to predialysis.
Review: Neuromuscular Disease in the Dialysis Patient: An Update for the Nephrologist
Authors: Krishnan Arun V. , Pussell Bruce A. , Kiernan Matthew C.
Published: April 2009

Neuromuscular disease is an extremely common complication of end‐stage kidney disease (ESKD), manifesting in almost all dialysis patients, and leading to weakness, reduced exercise capacity, and disability. Recent studies have suggested that hyperkalemia may underlie the development of neuropathy. As such, maintenance of serum K+ within normal limits between periods of dialysis in ESKD patients manifesting early neuropathic symptoms may reduce neuropathy development and progression. For patients with more severe neuropathic syndromes, increased dialysis frequency or a switch to high‐flux dialysis may prevent further deterioration, while ultimately, renal transplantation is required to improve and restore nerve function. Exercise training programs are beneficial for ESKD patients with muscle weakness due to neuropathy or myopathy, and are capable of improving exercise tolerance and quality of life. Specific treatments have recently been evaluated for symptoms of autonomic neuropathy, including sildenafil for impotence and midodrine for intra‐dialytic hypotension, and have been shown to be effective and well tolerated. Other important management strategies for neuropathy include attention to foot care to prevent callus and ulceration, vitamin supplementation, and erythropoietin. Treatment with membrane‐stabilizing agents, such as amitryptiline and gabapentin, are highly effective in patients with painful neuropathy.
Barriers to Satisfactory Migraine Outcomes. What Have We Learned, Where Do We Stand?
Authors: Bigal Marcelo , Krymchantowski Abouch Valenty , Lipton Richard B.
Published: April 2009

Barriers to optimal migraine care have traditionally been divided into a number of categories: under‐recognition and underconsultation by migraine sufferers; underdiagnosis and undertreatment by health care professionals; lack of follow‐up and treatment optimization. These “traditional” barriers have been recognized and addressed for at least 15 years. Epidemiologic studies suggest that consultation, diagnosis, and treatment rates for migraine have improved although many migraine sufferers still do not get optimal treatment. Herein, we revisit the problem, review areas of progress, and expand the discussion of barriers to migraine care. We hypothesize that the subjective nature of pain and difficulty in communicating it contributes to clinical and societal barriers to care. We then revisit some of the traditional barriers to care, contrasting rates of recognition, diagnosis, and treatment over the past 15 years. We follow by addressing new barriers to migraine care that have emerged as a function of the knowledge gained in this process.
The influence of concurrent anticonvulsants on the efficacy of the ketogenic diet
Authors: Morrison Peter F. , Pyzik Paula L. , Hamdy Rana , Hartman Adam L. , Kossoff Eric H.
Published: April 2009

It is unknown if any particular anticonvulsants modify the likelihood of seizure reduction when used in combination with the ketogenic diet (KD). A retrospective study was performed of 217 consecutive children who started the KD from 2000–2007. Patients included did not have any changes to their anticonvulsant dose. Efficacy data at 3 months on the KD were analyzed with respect to the six most frequently used anticonvulsants in this cohort. A total of 115 patients were included. Children receiving phenobarbital in combination with the KD were significantly less likely to have a >50% seizure reduction (p = 0.003). Conversely, those receiving zonisamide in combination with the KD at onset were more likely to have a >50% reduction (p = 0.04). These results provide practical information to clinicians who are treating children receiving both the KD and anticonvulsants.
Hippocampal distribution of vesicular glutamate transporter 1 in patients with temporal lobe epilepsy
Authors: Van Der Hel W. Saskia , Verlinde Suzanne A.M.W. , Meijer Dimphna H.M. , De Wit Marina , Rensen Marije G. , Van Gassen Koen L.I. , Van Rijen Peter C. , Van Veelen Cees W.M. , De Graan Pierre N.E.
Published: April 2009

Purpose:  Vesicular glutamate transporters (VGLUTs) are responsible for loading synaptic vesicles with glutamate, determining the phenotype of glutamatergic neurons, and have been implicated in the regulation of quantal size and presynaptic plasticity. We analyzed VGLUT subtype expression in normal human hippocampus and tested the hypothesis that alterations in VGLUT expression may contribute to long‐term changes in glutamatergic transmission reported in patients with temporal lobe epilepsy (TLE).

Methods:  VGLUT immunohistochemistry, immunofluorescence, in situ hybridization, Western blotting, and quantitative polymerase chain reaction (qPCR) were performed on biopsies from TLE patients without (non‐HS) and with hippocampal sclerosis (HS) and compared to autopsy controls and rat hippocampus. VGLUT1 expression was compared with synaptophysin, neuropeptide Y (NPY), and Timm’s staining.

Results:  VGLUT1 was the predominant VGLUT in human hippocampus and appeared to be localized to presynaptic glutamatergic terminals. In non‐HS hippocampi, VGLUT1 protein levels were increased compared to control and HS hippocampi in all subfields. In HS hippocampi VGLUT1 expression was decreased in subfields with severe neuronal loss, but strongly up‐regulated in the dentate gyrus, characterized by mossy fiber sprouting.

Discussion:  VGLUT1 is used as marker for glutamatergic synapses in the human hippocampus. In HS hippocampi VGLUT1 up‐regulation in the dentate gyrus probably marks new glutamatergic synapses formed by mossy fiber sprouting. Our data indicate that non‐HS patients have an increased capacity to store glutamate in vesicles, most likely due to an increase in translational processes or upregulation of VGLUT1 in synapses from afferent neurons outside the hippocampus. This up‐regulation may increase glutamatergic transmission, and thus contribute to increased extracellular glutamate levels and hyperexcitability.
Are the dichotomies generalized versus focal epilepsies and idiopathic versus symptomatic epilepsies still valid in modern epileptology?
Authors: Lüders Hans O. , Turnbull John , Kaffashi Farhad
Published: April 2009

In this commentary we discuss the basic concept of an epileptogenicity level, which is variable in different brain regions and is a function of multiple factors including the basic epileptogenicity level, routine environmental or internal stimuli, and various triggering and causative factors. This concept blurs the distinction between focal versus generalized and between idiopathic versus symptomatic epilepsies. We suggest dropping the dichotomy idiopathic versus symptomatic and to instead simply list the different etiologic factors that increase the epileptogenicity level. On the other hand, even if there is a continuum between focal and generalized epilepsies, most epilepsies are either predominantly focal or predominantly generalized. It is useful to maintain this distinction (even if somewhat artificial) because focal epilepsies can be treated with epilepsy surgery, and all focal epilepsies tend to respond to the same type of anticonvulsants. Generalized epilepsies cannot be treated surgically and respond to different anticonvulsants depending on the semiologic type of seizures.
Epilepsy surgery outcomes in temporal lobe epilepsy with a normal MRI
Authors: Bell Michael L. , Rao Satish , So Elson L. , Trenerry Max , Kazemi Noojan , Matt Stead S. , Cascino Gregory , Marsh Richard , Meyer Fredric B. , Watson Robert E. , Giannini Caterina , Worrell Gregory A.
Published: April 2009

Purpose:  To determine the long‐term efficacy of anterior temporal lobectomy for medically refractory temporal lobe epilepsy in patients with nonlesional magnetic resonance imaging (MRI).

Methods:  We identified a retrospective cohort of 44 patients with a nonlesional modern “seizure protocol” MRI who underwent anterior temporal lobectomy for treatment of medically refractory partial epilepsy. Postoperative seizure freedom was determined by Kaplan‐Meyer survival analysis. Noninvasive preoperative diagnostic factors potentially associated with excellent surgical outcome were examined by univariate analysis in the 40 patients with follow‐up of >1 year.

Results:  Engel class I outcomes (free of disabling seizures) were observed in 60% (24 of 40) patients. Preoperative factors associated with Engel class I outcome were: (1) absence of contralateral or extratemporal interictal epileptiform discharges, (2) subtraction ictal single photon emission computed tomography (SPECT) Coregistered to MRI (SISCOM) abnormality localized to the resection site, and (3) subtle nonspecific MRI findings in the mesial temporal lobe concordant to the resection.

Discussion:  In carefully selected patients with temporal lobe epilepsy and a nonlesional MRI, anterior temporal lobectomy can often render patients free of disabling seizures. This favorable rate of surgical success is likely due to the detection of concordant abnormalities that indicate unilateral temporal lobe epilepsy in patients with nonlesional MRI.
EFFECT OF CHROMIUM(VI) ON PHOTOSYSTEM II ACTIVITY AND HETEROGENEITY OF SYNECHOCYSTIS SP. (CYANOPHYTA): STUDIED WITH IN VIVO CHLOROPHYLL FLUORESCENCE TESTS1
Authors: Pan Xiangliang , Chen Xi , Zhang Daoyong , Wang Jianlong , Deng Chunnuan , Mu Guijin , Zhu Huaisong
Published: April 2009

The inhibitory effect of Cr(VI) on the PSII of Synechocystis sp. was studied. Cr(VI) reduced O2 evolution and inhibited the water‐splitting system in PSII. S‐states test and flash induction test showed that Cr(VI) exposure increased the proportion of inactivated PSII (PSIIX) and PSIIβ reaction centers, which increased the fluxes of dissipated energy. JIP test and QA− reoxidation test demonstrated that Cr(VI) treatment induces inhibition of electron transport from QA− to QB/QB− and accumulation of P680+. More QA− had to be oxidized through S2(QAQB)− charge recombination and oxidation by PQ9 molecules in PSII under Cr(VI) stress. These changes finally decreased the index of photosynthesis performance.
UNRAVELING THE REGULATION OF NITROGEN ASSIMILATION IN THE MARINE DIATOM THALASSIOSIRA PSEUDONANA (BACILLARIOPHYCEAE): DIURNAL VARIATIONS IN TRANSCRIPT LEVELS FOR FIVE GENES INVOLVED IN NITROGEN ASSIMILATION1
Authors: Brown Kathryn L. , Twing Katrina I. , Robertson Deborah L.
Published: April 2009

We examined the diurnal expression of five genes encoding nitrogen‐assimilating enzymes in the marine diatom Thalassiosira pseudonana (Hust.) Hasle et Heimdal following a transition from NH4+‐ to NO3−‐supplemented media. The accumulation of nia transcripts (encoding nitrate reductase, NR) following the transition to NO3−‐supplemented media was similar to previously reported changes in NR abundance and activity. Nia mRNA levels varied diurnally, and the diurnal oscillations were abolished when cells were transferred to continuous light. Genes encoding chloroplastic (niiA) and cytosolic (nirB) nitrite reductases were identified in the genome of T. pseudonana. NiiA and nirB transcript levels increased within 2 h following the addition of NO3− and varied diurnally. Patterns of diurnal variation in nia, niiA, and glnII (encoding the chloroplast‐localized glutamine synthetase) mRNA abundances were similar. NirB and glnN (encoding the cytosolic‐localized glutamine synthetase) mRNA levels also oscillated diurnally; however, the oscillation was out of phase with nia, niiA, and glnII. We propose that NO3− is assimilated into organic molecules in both the chloroplast and cytosol of diatoms and that enzymes encoded by nirB and glnN contribute to the ecologically important dark assimilation of NO3− observed in marine diatoms. As with nia, the diurnal variations in niiA, nirB, glnII, and glnN were abolished when cells were transferred to continuous light. Our results demonstrate that transcript accumulation is not circadian controlled, but, rather, changes in metabolic pools triggered by light:dark (L:D) transitions may be important in regulating the cellular mRNA levels encoding these key nitrogen assimilating enzymes.
TAXONOMIC STUDY OF TWO NEW GENERA OF FUSIFORM GREEN FLAGELLATES, TABRIS GEN. NOV. AND HAMAKKO GEN. NOV. (VOLVOCALES, CHLOROPHYCEAE)1
Authors: Nakada Takashi , Nozaki Hisayoshi
Published: April 2009

On the basis of LM, we isolated strains of two species of fusiform green flagellates that could be assigned to former Chlorogonium (Cg.) Ehrenb. One species, “Cg.”heimii Bourr., lacked a pyrenoid in its vegetative cells and required organic compounds for growth. The other was similar to Cg. elongatum (P. A. Dang.) Francé and “Cg.”acus Nayal, but with slightly smaller vegetative cells. Their molecular phylogeny was also studied based on combined 18S rRNA, RUBISCO LSU (rbcL), and P700 chl a‐apoprotein A2 (psaB) gene sequences. Both species were separated from Chlorogonium emend., Gungnir Nakada and Rusalka Nakada, which were formerly assigned to Chlorogonium. They were accordingly assigned to new genera, Tabris Nakada gen. nov. and Hamakko (Hk.) Nakada gen. nov. as T. heimii (Bourr.) Nakada comb. nov. and Hk. caudatus Nakada sp. nov., respectively. Tabris is differentiated from other genera of fusiform green flagellates by its vegetative cells, which only have two apical contractile vacuoles and lack a pyrenoid in the chloroplast. Hamakko, on the other hand, is distinguishable by the fact that its pyrenoids in vegetative cells are penetrated by flattened thylakoid lamellae.
Is Hyperglycemia Associated with Frailty Status in Older Women?
Authors: Blaum Caroline S. , Xue Qian Li , Tian Jing , Semba Richard D. , Fried Linda P. , Walston Jeremy
Published: April 2009

OBJECTIVES: To determine whether hyperglycemia is related to prevalent frailty status in older women.

DESIGN: Secondary data analysis of baseline data of a prospective cohort study.

SETTING: Baltimore, Maryland.

PARTICIPANTS: Five hundred forty‐three women aged 70 to 79.

METHODS: Research used baseline data from 543 participants in the Women's Health and Aging Studies I and II aged 70 to 79 who had all variables needed for analyses. The dependent variable was baseline frailty status (not frail, prefrail, frail), measured using an empirically derived model defining frailty according to weight loss, slow walking speed, weakness, exhaustion, and low activity (1–2 characteristics present=prefrail, ≥3=frail). Covariates included body mass index (BMI), interleukin‐6 (IL‐6), age, race, and several chronic diseases. Analyses included descriptive methods and multinomial logistic regression to adjust for key covariates.

RESULTS: A hemoglobin A1c (HbA1c) level of 6.5% or greater in older women was significantly associated with higher likelihood of prefrail and frail status (normal HbA1c <6.0% was reference). The association between HbA1C levels of 6.0% to 6.5% and frailty status was not different from that of normal HbA1c, but HbA1c levels of 6.5% to 6.9% had nearly twice the likelihood of frailty (odds ratio (OR)=1.96, 95% confidence interval (CI)=1.47–2.59) as normal HbA1c. A HbA1c level of 9.0% or greater was also strongly associated (OR=2.57, 95% CI=1.99,3.32). Significant associations were also seen between baseline prefrail and frail status and low (18.5–20.0 kg/m2) and high (>30.0 kg/m2) body mass index (BMI), interleukin‐6, and all chronic diseases evaluated, but controlling for these covariates only minimally attenuated the independent association between HbA1c and frailty status.

CONCLUSION: Hyperglycemia is associated with greater prevalence of prefrail and frail status; BMI, inflammation, and comorbidities do not explain the association. Longitudinal research and study of alternative pathways are needed.