bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disturbance, invasion and re‐invasion: managing the weed‐shaped hole in disturbed ecosystems
Authors: Buckley Yvonne M. , Bolker Benjamin M. , Rees Mark 
Published: June 2007

AbstractWe aim to develop a simple model to explore how disturbance and propagule pressure determine conditions for successful invasion in systems where recruitment occurs only in disturbed sites. Disturbance is often thought to favour invaders as it allows recruitment; however, the effects of disturbance are more complicated when it results in mortality of the invader. When disturbance rates in both invader occupied and unoccupied sites are the same, recruitment and mortality effects are exactly balanced, and successful invasion is independent of the disturbance regime. Differences in the disturbance rates between invader occupied and unoccupied sites can occur through invader modification or management of disturbance. Under these conditions, we found a novel mechanism for the generation of an Allee effect, which occurs when the invader promotes disturbance in sites it already occupies. When Allee effects occur one‐off, large‐scale disturbances can result in permanent, dramatic shifts in invader abundance; and conversely, reducing the population below a critical threshold can cause extinction.
A new era in finding Type 2 diabetes genes—the unusual suspects
Authors: Frayling T. M. 
Published: June 2007

AbstractIn 1988 the task of identifying Type 2 diabetes genes was described as a nightmare. For the next 17 years this proved to be largely correct. In the meantime the prevalence of Type 2 diabetes rose sharply due to non‐genetic factors, compounding the problem of trying to find genes. Despite a huge amount of effort, progress was disappointing and only two genes, PPARG and KCNJ11, were confirmed beyond doubt as Type 2 diabetes risk factors in multiple studies. The reasons for this have been well documented and mainly consist of the use of inappropriate levels of statistical inference given the many hundreds of thousands of potential risk polymorphisms in the genome and their small effect sizes. The good news is that these problems are now surmountable and prospects for finding many more genes are bright. This year saw the identification of a third gene, TCF7L2, that has a greater impact on risk than the first two and provided important lessons for Type 2 diabetes genetic studies. The most important of these lessons was that previously unsuspected genes may be involved. In this review I discuss why this year is the start of a new era in our understanding of Type 2 diabetes genes and how this may lead to improved patient care.
The introduction of the European bitterling (Rhodeus amarus) to west and central Europe
Authors: Damme Dirk Van , Bogutskaya Nina , Hoffmann Richard C. , Smith Carl 
Published: June 2007

AbstractThe European bitterling is considered to be a native species over much of its present range in Europe. A dramatic decline in its abundance from 1960 to 1980 in west and central Europe, attributed to aquatic pollution, led to the establishment of stringent national and international regulations for protection of the species. Here, we review the evidence that until AD 1100 the bitterling was restricted to the Ponto‐Caspian and Aegean regions (south‐eastern Europe and adjacent regions of Asia Minor) and only expanded into its present range during the 19th century. The earliest records of bitterling in west and central Europe are from regions where carp cultivation was common and the bitterling appears to have spread into this region in association with the gradual expansion of carp cultivation. After an initial period of expansion, between approximately 1150 and 1560 in regions with carp cultivation, the species virtually disappeared from Europe during the coldest period of the Little Ice Age. Bitterling reappeared at the end of the 18th century, initially in historical centres of carp cultivation, and was again abundant and widespread in Europe by around 1850. Its reappearance appears to have been through expansion of refuge populations as well as new invasions. The decline in abundance of bitterling during the period 1960–80 in west and central Europe appears not only to have been caused by pollution, as is generally believed, but may also be correlated with low spring temperatures. From approximately 1980 onwards the European bitterling once again expanded its distribution in many parts of Europe, particularly in eastern Europe. This recent expansion may be due to a combination of factors, including a rise in ambient temperature coupled with an increase in anthropogenic dispersal and changes to aquatic habitats favourable to bitterling. Thus, the bitterling, which is legally protected in Europe at a national and international level as an endangered indigenous species, is actually an invasive species and a parasite of freshwater mussels. Its current expansion in distribution could pose a hazard to freshwater mussel populations in regions where they are already threatened.
The Trouble with David Goodhart's Britain
Authors: PATHAK PATHIK 
Published: June 2007

This article argues that David Goodhart's manifesto for ‘progressive nationalism’ is gravely misconceived, indicative of the entire cohesion and integration agenda. What he talks about as the making of a common culture involves dusting off tired traditions, scaling back individual rights to protect the ‘common good’, and ultimately retreating onto safe ground for Middle England. Since such measures to strengthen national solidarity are responsive only to the anxieties of the demographic majority, those who are deemed to be most prone to social marginalisation continue to be so. Goodhart, like many in New Labour's orbit, chooses to ignore that belonging is reciprocal.The article advocates an alternative culture of citizenship ‐ one that widens democratisation, brings individuals them into the political process and thereby engages the ‘reciprocity of belonging’ that the post‐7/7 consensus neglects. To build a cohesive Britain, the first step ‐ but not necessarily the last ‐ is to conceive sustainable routes towards social and political inclusion for all.
Maximum Likelihood Estimation: for the Multinomial Distribution
Authors: Davis Charles S , Jones Michael P 
Published: June 2007

SummaryIn a first course in mathematical statistics or categorical data analysis, the maximum likelihood estimators of the parameters of the multinomial distribution are often “derived” using calculus. However, the important step of verifying that the resulting estimators indeed maximize the likelihood is omitted or done incorrectly. In this paper, two simple methods of obtaining the maximum likelihood estimates are presented.
Leukocyte cDNA Analysis of NSD1 Derived from Confirmed Sotos Syndrome Patients
Authors: Duno M. , Skovby F. , Schwartz M. 
Published: June 2007

Summary Background: Haploinsufficiency of the NSD1 gene leads to Sotos syndrome (Sos), which is characterised by excessive growth, especially during childhood, distinct craniofacial features and variable degree of mental impairment. A wide spectrum of NSD1 mutations have been described in Sos patients, ranging from more than 100 different single nucleotide changes, to partial gene deletions, and to microdeletions of various sizes comprising the entire NSD1 locus. Objective: To investigate the NSD1 cDNA sequence in genetically confirmed Sos patients harbouring truncating and missense mutations. Method: Total RNA was isolated from a 250 μl standard EDTA blood sample from nine genetically verified Sos patients, and subsequent reverse‐transcribed into cDNA followed by PCR and direct sequencing of specific NSD1 cDNA sequences. Results: All nine mutations, including missense, nonsense and whole exon deletions, previously identified in genomic DNA, could confidently be detected in cDNA. Several NSD1 transcript splice variants were detected. Conclusion: Despite the fact that Sos is caused by haploinsufficiency, NSD1 transcripts containing nonsense and frame shift mutations can be detected in leukocyte‐derived cDNA. The possibility therefore exists that certain NSD1 mutations are expressed and contribute to the phenotypic variability of Sos. NSD1 cDNA analysis is likely to enhance mutation detection in Sos patients.
Evolutionary implications of bite mechanics and feeding ecology in bears
Authors: Christiansen P. 
Published: June 2007

AbstractBite forces (BFs) based on a dry skull static model were computed for 122 specimens of all eight species of extant ursids. It was found that the giant panda has high BFs for its body size, and large moment arms about the temporomandibular joint, both muscle inlever moment arms and outlever moment arms to the carnassial and canine. The insectivorous sloth bear and to some extent the omnivorous black bears were the opposite. The small sun bear has very large canines and high BFs, which are not well understood, but could potentially be related to its frequent opening of tropical hardwood trees in pursuit of insects. Force profiles along the lower jaw revealed significant differences among the various species, both related to diet and inferred applied BFs. The panda is the only specialized ursid with respect to craniodental morphology and BFs, but is still unspecialized for herbivory compared with other large, herbivorous mammals, probably owing to a rather short evolutionary history, but possibly its morphology is constrained by genealogy. The low BFs in the sloth bear and its mandibular force profiles are derived for a diet of insects and fruit, requiring only low BFs and largely dorsoventral bite moments. In contrast, the unspecialized morphology and moderate BFs relative to body size of the polar bear and spectacled bear are probably also a result of a short evolutionary history.
Diet of free‐ranging cats and dogs in a suburban and rural environment, south‐eastern Brazil
Authors: Campos C. B. , Esteves C. F. , Ferraz K. M. P. M. B. , Crawshaw P. G. , Verdade L. M. 
Published: June 2007

AbstractIn spite of the worldwide occurrence of domestic cats and dogs, and their close relationship with humans, the number of published papers on free‐ranging cats Felis catus and dogs Canis familiaris, is small. The diet of both species was estimated in a suburban and rural environment in July 2002 and January 2003. Visual observations and scat collection of both species were accomplished along a 10 km transect line in the Campus ‘Luiz de Queiroz’, University of São Paulo, Piracicaba, south‐eastern Brazil. The diet of both species was determined by analysis of sterilized, washed, dried and sorted scats. Estimated abundances of free‐ranging cats and dogs in the sampled area were 81 (±4.32) and 42 (±2.96), respectively. Cats and dogs were more abundant in the suburban than in the rural environment (t=3.78, P<0.001, N=55; t=8.38, P<0.001, N=55, respectively) and cats were more abundant than dogs in the suburban environment (t=6.76, P<0.001, N=55), even though there was no significant difference between the abundance of both species in the rural environment (t=0.82, P=0.46, N=55). Invertebrates were the most commonly consumed item by both species, followed by mammals (cats: 63.24 and 20.51%; dogs: 57.05 and 25.15%, respectively). Niche breadth was 0.4892 for cats and 0.4463 for dogs. Niche overlap was almost complete (0.97108). The consumption of mammals was estimated to be between 16.76 and 25.42 kg  individual−1year−1 for dogs and between 2.01 and 2.9 kg individual−1year−1 for cats. These data might be useful to establish a management program to minimize the predation pressure of free‐ranging cats and dogs on wildlife.
Phosphodiesterase type 2 and the homeostasis of cyclic GMP in living thalamic neurons
Authors: Hepp R. , Tricoire L. , Hu E. , Gervasi N. , Paupardin‐Tritsch D. , Lambolez B. , Vincent P. 
Published: June 2007

AbstractThe ubiquitous second messenger cyclic GMP (cGMP) is synthesized by soluble guanylate cyclases in response to nitric oxide (NO) and degraded by phosphodiesterases (PDE). We studied the homeostasis of cGMP in living thalamic neurons by using the genetically encoded fluorescence resonance energy transfer sensor Cygnet, expressed in brain slices through viral gene transfer. Natriuretic peptides had no effect on cGMP. Basal cGMP levels decreased upon inhibition of NO synthases or soluble guanylate cyclases and increased when PDEs were inhibited. Single cell RT‐PCR analysis showed that thalamic neurons express PDE1, PDE2, PDE9, and PDE10. Basal cGMP levels were increased by the PDE2 inhibitors erythro‐9‐(2‐hydroxy‐3‐nonyl) adenine (EHNA) and BAY60‐7550 but were unaffected by PDE1 or PDE10 inhibitors. We conclude that PDE2 regulates the basal cGMP concentration in thalamic neurons. In addition, in the presence of 3‐isobutyl‐1‐methylxanthine (IBMX), cGMP still decreased after application of a NO donor. Probenecid, a blocker of cGMP transporters, had no effect on this decrease, leaving PDE9 as a possible candidate for decreasing cGMP concentration. Basal cGMP level is poised at an intermediate level from which it can be up or down‐regulated according to the cyclase and PDE activities.
Electroconvulsive shock treatment differentially modulates cortical and subcortical endocannabinoid activity
Authors: Hill Matthew N. , Barr Alasdair M. , Ho W.‐S. Vanessa , Carrier Erica J. , Gorzalka Boris B. , Hillard Cecilia J. 
Published: June 2007

AbstractPrevious studies indicate that the endocannabinoid system is a potential target for the treatment of depression. To further examine this question we assessed the effects of electroconvulsive shock (ECS) treatment, both a single session and 10 daily sessions, on endocannabinoid content, CB1 receptor binding parameters and CB1 receptor‐mediated [35S]GTPγS binding in the prefrontal cortex, hippocampus, hypothalamus and amygdala. A single ECS session resulted in a general reduction in the binding affinity of the CB1 receptor in all brain regions examined, as well as reductions in N‐arachidonylethanolamine (anandamide) content in the prefrontal cortex and the hippocampus, reduced hydrolysis of anandamide by fatty acid amide hydrolase (FAAH) in the prefrontal cortex and an increase in the binding site density of the CB1 receptor in the amygdala. Following 10 ECS sessions, all these effects subsided except for the reductions in anandamide content in the prefrontal cortex, which increased in magnitude, as well as the reductions in FAAH activity in the prefrontal cortex. Additionally, repeated ECS treatment resulted in a significant reduction in the binding site density of the CB1 receptor in the prefrontal cortex, but did not alter CB1 receptor‐mediated [35S]GTPγS binding. Repeated ECS treatment also significantly enhanced the sensitivity of CB1 receptor‐mediated [35S]GTPγS binding in the amygdala. Collectively, these data demonstrate that ECS treatment results in a down‐regulation of cortical and an up‐regulation of subcortical endocannabinoid activity, illustrating the possibility that the role of the endocannabinoid system in affective illness may be both complex and regionally specific.
The impact of metabolic state on Cd adsorption onto bacterial cells
Authors: JOHNSON K. J. , AMS D. A. , WEDEL A. N. , SZYMANOWSKI J. E. S. , WEBER D. L. , SCHNEEGURT M. A. , FEIN J. B. 
Published: June 2007

ABSTRACTThis study examines the effect of bacterial metabolism on the adsorption of Cd onto Gram‐positive and Gram‐negative bacterial cells. Metabolically active Gram‐positive cells adsorbed significantly less Cd than non‐metabolizing cells. Gram‐negative cells, however, showed no systematic difference in Cd adsorption between metabolizing and non‐metabolizing cells. The effect of metabolism on Cd adsorption to Gram‐positive cells was likely due to an influx of protons in and around the cell wall from the metabolic proton motive force, promoting competition between Cd and protons for adsorption sites on the cell wall. The relative lack of a metabolic effect on Cd adsorption onto Gram‐negative compared to Gram‐positive cells suggests that Cd binding in Gram‐negative cells is focused in a region of the cell wall that is not reached, or is unaffected by this proton flux. Thermodynamic modeling was used to estimate that proton pumping causes the pH in the cell wall of metabolizing Gram‐positive bacteria to decrease from the bulk solution value of 7.0 to approximately 5.7.
Physiological determinants of the variation in left ventricular mass from early adolescence to late adulthood in healthy subjects
Authors: Cain Peter A. , Ahl Ragnhild , Hedstrom Erik , Ugander Martin , Allansdotter‐Johnsson Ase , Friberg Peter , Marild Staffan , Arheden Hakan 
Published: June 2007

SummaryBackground:  The physiological determinants of left ventricular mass (LVM) measured by cardiac magnetic resonance (CMR) imaging are not well defined as prior investigators have studied either adults or adolescents in isolation or have not strictly excluded hypertension or accounted for the effects of exercise habits, haemodynamic, demographic, or body shape characteristics.Methods:  Ninety‐seven healthy volunteers (11–81 years, 51 males) underwent CMR. All parameters [unstandardized and adjusted for body surface area (BSA)] were analysed according to gender and by adolescence versus adulthood (adolescents <20 years, adults ≥20 years). The influence of haemodynamic factors, exercise and demographic factors on LVM were determined with multivariate linear regression.Results:  Left ventricular mass rose during adolescence and declined in adulthood. LVM and LVMBSA were higher in males both in adults (LVM: 188 ± 22 versus 140 ± 21 g, P<0·001; LVMBSA: 94 ± 11 versus 80 ± 11 g m−2, P<0·001) and in adolescents when adjusted for BSA (LVM: 128 ± 29 versus 107 ± 20 g, P = 0·063; LVMBSA: 82 ± 8 versus 71 ± 10 g m−2, P = 0·025). In adults, systolic blood pressure (SBP) and self‐reported physical activity increased while meridional and circumferential wall stress were constant with age. Multivariate regression analysis revealed age, gender and BSA as the major determinants of LVM (global R2 = 0·68).Conclusions:  Normal LVM shows variation over a broad age range in both genders with a rise in adolescence and subsequent decline with increasing age in adulthood despite an increase in SBP and physical activity. BSA, age and gender were found to be major contributors to the variation in LVM in healthy adults, while haemodynamic factors, exercise and wall stress were not.
An International Multicenter Randomized Double‐Blind Controlled Trial of Lamotrigine and Sustained‐Release Carbamazepine in the Treatment of Newly Diagnosed Epilepsy in the Elderly
Authors: Saetre Erik , Perucca Emilio , Isojärvi Jouko , Gjerstad Leif ,   on behalf of the LAM 40089 Study Group
Published: June 2007

Summary:  Purpose: To assess the comparative effectiveness, efficacy, and tolerability of lamotrigine (LTG) and sustained‐release carbamazepine (CBZ) in the treatment of newly diagnosed epilepsy in the elderly. Methods: Patients aged 65 years or older, who had experienced at least two unprovoked partial and/or generalized tonic–clonic seizures, were randomized to receive LTG (n = 93) or CBZ (n = 92) according to a multicenter double‐blind, parallel‐group design. Trial duration was 40 weeks and included a 4‐week dose escalation followed by a maintenance phase during which dosages could be adjusted according to response. Initial, maintenance and maximum dosages were 25 mg, 100 mg, and 500 mg per day for LTG, and 100 mg, 400 mg, and 2,000 mg per day for CBZ, respectively. The primary end point was retention in the trial. Results: In the LTG group, 68 patients (73%) completed the 40‐week study period compared with 61 (67%) in the CBZ group, a nonsignificant difference. Time to withdrawal from any cause did not differ between groups (p = 0.34). The number of subjects who completed the 40‐week period and were seizure free in the last 20 weeks was 48 (52%) in the LTG group and 52 (57%) in the CBZ group. Adverse events leading to withdrawal occurred in 13 (14%) subjects in the LTG group and 23 (25%) subjects in the CBZ group. Conclusion: LTG and CBZ showed comparable effectiveness, with a trend for higher seizure‐free rates for CBZ and better tolerability for LTG. Differences in outcome compared with previous trials may be related to different dosing rates and use of a sustained‐release formulation for CBZ.
Jackson, Todd, and the Concept of “Discharge” in Epilepsy
Authors: Reynolds Edward H. 
Published: June 2007

Summary: Purpose:To explore the historical origins of the modern concept of electrical discharges in the brain in epilepsy.Methods:I have examined the writings of Hughlings Jackson (1835–1911) and Robert Bentley Todd (1809–1860), especially their Lumleian Lectures on convulsive disorders to the Royal College of Physicians of 1890 and 1849, respectively; and also the influence of Herbert Spencer (1820–1903) on the former and Michael Faraday (1791–1867) on the latter.Results/Conclusions:Contrary to the widely taught view that Jackson was the first to propose electrical discharges in epilepsy it is clear that the discharges suggested by Jackson, influenced by the evolutionary philosopher, Herbert Spencer, were chemical, based on katabolism and anabolism. Jackson had no understanding or proposal based on physics or electricity. On the other hand, Todd had earlier proposed and described electrical concepts of discharges in epilepsy, influenced by his contemporary and colleague in London, Michael Faraday, who at the time was laying the foundations of our modern understanding of electricity and magnetism. Todd and Faraday saw “nervous polarity” as another polar force interchangeable with the polar forces of electricity and magnetism.
Large‐scale generation of autologous dendritic cells for immunotherapy in patients with acute myeloid leukemia
Authors: Schmitt Anita , Reinhardt Peter , Hus Iwona , Tabarkiewicz Jacek , Roliñski Jacek , Barth Thomas , Giannopoulos Krzysztof , Dmoszyñska Anna , Wiesneth Markus , Schmitt Michael 
Published: June 2007

BACKGROUND: Mononuclear cells (MNCs) of severely impaired acute myeloid leukemia (AML) patients may be collected by leukapheresis for large‐scale generation of dendritic cells (AML‐DCs) under good manufacturing practice (GMP) conditions for adoptive immunotherapy.STUDY DESIGN AND METHODS: In five end‐stage AML patients, a leukapheresis procedure was performed with a cell separator (either COBE Spectra [Gambro BCT] or Amicus [Baxter]). For large‐scale AML‐DC generation, the MNCs of a single leukapheresis concentrate were isolated by density gradient and plated into a cell factory under GMP conditions. The AML‐DCs were harvested on Day 8 of culture, and their viability, the mature morphology, and the phenotype were evaluated. The AML‐DCs were injected subcutaneously into five AML patients up to four times at a biweekly interval.RESULTS: All AML patients entered the leukapheresis procedure with a highly pathologic blood count. In a mean separation time of 198 ± 33 minutes, a mean of 1.3 ± 0.2‐fold the total blood volume was processed with a white blood cell (WBC) yield of 9 × 109 to 70 × 109 per collection dependent on the precollection WBC count. After density gradient a mean of 2.2 × 109 ± 0.3 × 109 MNCs were plated into a cell factory. This resulted in a mean viable and mature DC yield of 0.01 × 109 of MNCs.CONCLUSION: The leukapheresis procedure is a feasible and safe procedure even in patients with hematologic malignancies and highly pathologic blood counts. Sufficient amounts of MNCs can be collected in leukopenic patients and the large‐scale generation of AML‐DCs in cell factories under GMP conditions yields in an adequate quantity of viable and mature AML‐DCs.