bluuebunny/crossref_metadata_2025_split huggingface dataset:
Niche width collapse in a resilient top predator following ecosystem fragmentation
Authors: Layman Craig A. , Quattrochi John P. , Peyer Caroline M. , Allgeier Jacob E. 
Published: July 2007

AbstractMuch research has focused on identifying species that are susceptible to extinction following ecosystem fragmentation, yet even those species that persist in fragmented habitats may have fundamentally different ecological roles than conspecifics in unimpacted areas. Shifts in trophic role induced by fragmentation, especially of abundant top predators, could have transcendent impacts on food web architecture and stability, as well as ecosystem function. Here we use a novel measure of trophic niche width, based on stable isotope ratios, to assess effects of aquatic ecosystem fragmentation on trophic ecology of a resilient, dominant, top predator. We demonstrate collapse in trophic niche width of the predator in fragmented systems, a phenomenon related to significant reductions in diversity of potential prey taxa. Collapsed niche width reflects a homogenization of energy flow pathways to top predators, likely serving to destabilize remnant food webs and render apparently resilient top predators more susceptible to extinction through time.
On the stability of populations of mammals, birds, fish and insects
Authors: Sibly Richard M. , Barker Daniel , Hone Jim , Pagel Mark 
Published: July 2007

AbstractA key concern for conservation biologists is whether populations of plants and animals are likely to fluctuate widely in number or remain relatively stable around some steady‐state value. In our study of 634 populations of mammals, birds, fish and insects, we find that most can be expected to remain stable despite year to year fluctuations caused by environmental factors. Mean return rates were generally around one but were higher in insects (1.09 ± 0.02 SE) and declined with body size in mammals. In general, this is good news for conservation, as stable populations are less likely to go extinct. However, the lower return rates of the large mammals may make them more vulnerable to extinction. Our estimates of return rates were generally well below the threshold for chaos, which makes it unlikely that chaotic dynamics occur in natural populations – one of ecology’s key unanswered questions.
Nephrolithiasis in identical twins: the impact of nature vs nurture
Authors: Haleblian George E. , Cantor David A. , Sur Roger L. , Assimos Dean G. , Preminger Glenn M. 
Published: July 2007

In a unique paper from the USA, authors look at the interplay between environmental, genetic and anatomical factors in the development of kidney stones. They suggest that additional controlled studies of monozygotic stone‐forming twins are required for further elaboration of this interaction.OBJECTIVETo assess possible underlying metabolic abnormalities in three sets of monozygotic twins, to evaluate the interplay among the factors of kidney stone formation, a complex multifactorial process influenced by environmental, genetic and anatomical factors.PATIENTS AND METHODSThree sets of identical twins with either cystine or calcium oxalate stones were identified. Demographic data, medical histories and the results of 24‐h urine testing, with samples collected on self‐selected diets, were reviewed and analysed.RESULTSThe cystinuric twins had very similar cystine excretion rates, while stone activity was significantly more pronounced in one. Metabolic abnormalities were concordant in one set of twins with calcium oxalate stones, both being hypercalciuric and hyperuricosuric. However, metabolic abnormalities were discordant in the other pair, one twin with hypercalciuria and the other with hypocitraturia. Two of the three pairs had low urinary volume.CONCLUSIONSThese results support previous observations that environmental, genetic and potentially, anatomical factors play roles in kidney‐stone formation. Additional controlled studies of monozygotic stone‐forming twins might help to define the interplay between environmental and genetic factors, and allow the identification of susceptibility genes involved in stone generation.
Genetic impact on prostate anatomical variability during ageing: role of CYP17, SRD5A2 and androgen receptor genes polymorphisms
Authors: Larré Stéphane , Hamadeh Hikmat , Azzouzi Abdel Rahmene , Vallancien Guy , Cochand‐Priollet Beatrix , Cancel‐Tassin Géraldine , Cussenot Olivier 
Published: July 2007

OBJECTIVESTo investigate the role of genetic determinism on individual variability in age‐related prostate changes, as defining ‘normal’ anatomy in prostate gland ageing is a challenge because the variability of changes in prostate morphology increases with age.MATERIALS AND METHODSWe assessed the influence of androgen‐ and oestrogen‐regulating genetic polymorphisms on age‐related weight and stromal‐ratio changes in the prostate, using an anatomical, autopsy‐based study. We quantified weight and glandular/stromal ratio in 85 autopsy prostates from men aged > 50 years. We genotyped allelic variants of androgen‐regulating genes [androgen receptor (CAG repeats) and type II 5‐α reductase (TA repeat and V89L)] and an oestrogen‐regulating gene (A1/A2 variants of the 17α‐hydroxylase (CYP17)).RESULTSThere was a fair negative correlation between prostate weight and the number of CAG repeats (r = −0.32, P = 0.003); the group with ≤ 19 CAG repeats had heavier prostates than the ≥ 20 group (P = 0.015). The stromal ratio was higher in the group with 20–23 CAG repeats (P = 0.02) and in the A2A2 group of the CYP17 polymorphism (P = 0.016) compared with the other groups mixed together.CONCLUSIONA low number of CAG repeats is associated with higher prostate weights. The A2A2 genotype of CYP17 is associated with a higher stromal ratio.
Genome‐wide analysis for micro‐aberrations in familial exstrophy of the bladder using array‐based comparative genomic hybridization
Authors: Reutter Heiko , Hoischen Alexander , Ludwig Michael , Stein Raimund , Radlwimmer Bernhard , Engels Hartmut , Wolffenbuttel Katja P. , Weber Ruthild G. 
Published: July 2007

OBJECTIVEExstrophy of the bladder (EB) is part of the bladder‐exstrophy‐epispadias complex (BEEC). Because familial occurrence of BEEC is rare, exogenous factors are thought to play a major role in the etiology of most BEEC cases. We aimed to investigate a possible genetic basis of BEEC in a consanguineous kindred of Moroccan origin with three members showing the same phenotypic expression of BEEC.PATIENTS AND METHODSThe three affected males (two cousins and their maternal uncle) all presenting with nonsyndromic classic EB, were born in Morocco or The Netherlands. One Moroccan patient had an open bladder surface for 22 years due to late surgical reconstruction, avoided upright posture and developed severe lumbar scoliosis. Because three maternally related males from a consanguineous family living in different environments are affected, a genetic basis for EB is likely in this family. To screen for chromosomal aberrations and micro‐aberrations in the two patients who were still alive, conventional karyotyping and array‐based comparative genomic hybridization (array‐CGH) were used on DNA‐microarrays with a genome‐wide average resolution of <0.5 Mb.RESULTSChromosome banding revealed normal karyotypes. By array‐CGH, one of 8000 clones was aberrant in both affected cousins. This clone from 1p21.1 contained the AMY1B, AMY2B, AMY2A genes coding for salivary and pancreatic amylases.CONCLUSIONThe aberration detected by array‐CGH in both affected cousins is a known copy‐number variant and most likely unrelated to the EB‐phenotype. Nevertheless, in this family the nonsyndromic EB could be a monogenic disorder inherited in an autosomal‐recessive or X‐linked fashion.
Choosing What to Protect: Strategic Defensive Allocation against an Unknown Attacker
Authors: BIER VICKI , OLIVEROS SANTIAGO , SAMUELSON LARRY 
Published: July 2007

AbstractWe study a strategic model in which a defender must allocate defensive resources to a collection of locations and an attacker must choose a location to attack. In equilibrium, the defender sometimes optimally leaves a location undefended and sometimes prefers a higher vulnerability at a particular location even if a lower risk could be achieved at zero cost. The defender prefers to allocate resources in a centralized (rather than decentralized) manner, the optimal allocation of resources can be non‐monotonic in the value of the attacker's outside option, and the defender prefers her defensive allocation to be public rather than secret.
When Redistribution Leads to Regressive Taxation
Authors: HARITON CYRIL , PIASER GWENAËL 
Published: July 2007

AbstractWe introduce labor contracts in a framework of optimal redistribution: firms have some local market power and try to discriminate among heterogeneous workers. In this setting we show that if the firms have perfect information, i.e., they perfectly discriminate against workers and take all the surplus, the best tax function is flat. If firms have imperfect information, i.e., if they offer incentive contracts, then (under some assumptions) the best redistributive taxation is regressive.
Preemptive Competition in City Development
Authors: HEUBECK STEVEN 
Published: July 2007

AbstractThe rise of decentralization and polycentrism in cities raises questions of optimality. This paper proposes a model of two competing developers that generates new development prior to the optimal time. If demand is growing for new developments, the development built later will have potentially lower present value profitability, due to discounting, when compared to the earlier development. Both developers compete to gain the “first‐mover advantage” to build the first of the two developments, and developing sooner than what is optimal achieves this goal. This preemptive theory of competition offers a result that cities are more decentralized and polycentric than what is optimal.
Poverty‐Reducing and Welfare‐Improving Marginal Public Price and Price Cap Reforms
Authors: MAKDISSI PAUL , WODON QUENTIN 
Published: July 2007

AbstractThis paper extends familiar results on the optimal pricing of publicly provided goods and price cap regulations in a stochastic dominance framework. The key advantage is that the assessment as to whether pricing or price cap reforms are poverty reducing or welfare improving is not contingent on any given social welfare function. Rather, robust assessments of the impact of reforms can be made for wide classes of ethical judgments.
On the Choice of Public Pensions when Income and Life Expectancy Are Correlated
Authors: BORCK RAINALD 
Published: July 2007

AbstractThe paper presents a model where public pensions are determined by majority voting. Voters differ by age and income. Moreover, life expectancy increases with income. Depending on the strength of the link between contributions and benefits, and the relationship between income and life expectancy, individually optimal tax rates may increase or decrease with income. If they decrease, high tax rates are supported by pensioners and poor workers. If they increase with income, the coalition for high tax rates consists of pensioners and rich workers. “Ends against the middle” equilibria are also possible.
Molecular and cellular characterization of the age‐related neuroinflammatory processes occurring in normal rat hippocampus: potential relation with the loss of somatostatin GABAergic neurons
Authors: Gavilán M. Paz , Revilla Elisa , Pintado Cristina , Castaño Angélica , Vizuete M. Luisa , Moreno‐González Inés , Baglietto‐Vargas David , Sánchez‐Varo Raquel , Vitorica Javier , Gutiérrez Antonia , Ruano Diego 
Published: July 2007

AbstractIncreased neuroinflammatory reaction is frequently observed during normal brain aging. However, a direct link between neuroinflammation and neurodegeneration during aging has not yet been clearly shown. Here, we have characterized the age‐related hippocampal inflammatory processes and the potential relation with hippocampal neurodegeneration. The mRNA expression of the pro‐inflammatory cytokines IL‐1β and tumor necrosis factor‐α (TNF‐α), and the iNOs enzyme was significantly increased in aged hippocampus. Accordingly, numerous activated microglial cells were observed in aged rats. These cells were differentially distributed along the hippocampus, being more frequently located in the hilus and the CA3 area. The mRNA expression of somatostatin, a neuropeptide expressed by some GABAergic interneurons, and the number of somatostatin‐immunopositive cells decreased in aged rats. However, the number of hippocampal parvalbumin‐containing GABAergic interneurons was preserved. Interestingly, in aged rats, the mRNA expression of somatostatin and IL‐1β was inversely correlated and, the decrease in the number of somatostatin‐immunopositive cells was higher in the hilus of dentate gyrus than in the CA1 region. Finally, intraperitoneal chronic lipopolysaccharide (LPS) injection in young animals mimicked the age‐related hippocampal inflammation as well as the decrease of somatostatin mRNA expression. Present results strongly support the neuroinflammation as a potential factor involved in the age‐related degeneration of somatostatin GABAergic cells.
High mobility group box 1 protein is released by neural cells upon different stresses and worsens ischemic neurodegeneration in vitro and in vivo
Authors: Faraco G. , Fossati S. , Bianchi M. E. , Patrone M. , Pedrazzi M. , Sparatore B. , Moroni F. , Chiarugi A. 
Published: July 2007

AbstractHigh mobility group proteins are chromatin binding factors with key roles in maintenance of nuclear homeostasis. The evidence indicates that extracellularly released high mobility group box 1 (HMGB1) protein behaves as a cytokine, promoting inflammation and participating to the pathogenesis of several disorders in peripheral organs. In this study, we have investigated the expression levels and relocation dynamics of HMGB1 in neural cells, as well as its neuropathological potential. We report that HMGB1 is released in the culture media of neurons and astrocytes challenged with necrotic but not apoptotic stimuli. Recombinant HMGB1 prompts induction of pro‐inflammatory mediators such as inducible nitric oxide synthase (iNOS), cyclooxygenase‐2, interleukin‐1β, and tumor necrosis factor α, and increases excitotoxic as well as ischemic neuronal death in vitro. Dexamethasone reduces HMGB1 dependent immune glia activation, having no effect on the protein’s neurotoxic effects. HMGB1 is expressed in the nucleus of neurons and astrocytes of the mouse brain, and promptly (1 h) translocates into the cytoplasm of neurons within the ischemic brain. Brain microinjection of HMGB1 increases the transcript levels of pro‐inflammatory mediators and sensitizes the tissue to the ischemic injury. Together, data underscore the neuropathological role of nuclear HMGB1, and point to the protein as a mediator of post‐ischemic brain damage.
Nicotine‐induced phosphorylation of ERK in mouse primary cortical neurons: evidence for involvement of glutamatergic signaling and CaMKII
Authors: Steiner Rebecca C. , Heath Christopher J. , Picciotto Marina R. 
Published: July 2007

AbstractExtracellular signal‐regulated kinase (ERK) is activatedin vivoin a number of brain areas by nicotine and other drugs of abuse. Here we show that nicotine stimulation of cultured mouse cortical neurons leads to a robust induction of ERK phosphorylation that is dependent on nicotine concentration and duration of exposure. Calcium/calmodulin‐dependent protein kinase II activity is necessary for nicotine‐induced ERK phosphorylation and neither cAMP‐dependent protein kinase or protein kinase C appear to be involved. Activity of glutamate receptors, L‐type voltage‐gated calcium channels, and voltage‐gated sodium channels are also required for nicotine‐induced ERK phosphorylation. Nicotine‐induced ERK phosphorylation was inhibited by high concentrations of mecamylamine, however it was not blocked by other broad nicotinic acetylcholine receptor (nAChR) inhibitors (including hexamethonium and chlorisondamine) or nAChR subtype selective inhibitors (such as methyllycaconitine, alpha‐bungarotoxin, dihydro‐beta‐erythroidine, and α‐conotoxin Au1B). In accord with these pharmacological results, nicotine‐induced ERK phosphorylation was normal in primary cultures made from β2 or α7 nAChR subunit knockout mice. The α3/β4 nAChR agonist cytisine did not induce ERK phosphorylation suggesting that α3/β4 nAChRs were not involved in this process. Taken together, these data define a necessary role for glutamatergic signaling and calcium/calmodulin‐dependent protein kinase II in nicotine‐induced ERK phosphorylation in cortical neurons and do not provide evidence for the involvement of classical nAChRs.
Calcineurin activity is required for depolarization‐induced, CREB‐dependent gene transcription in cortical neurons
Authors: Kingsbury Tami J. , Bambrick Linda L. , Roby Clinton D. , Krueger Bruce K. 
Published: July 2007

AbstractCyclic AMP response element binding protein (CREB) functions as an activity‐dependent transcription factor in the nervous system. Increases in intracellular Ca2+ due to neuronal activity lead to the phosphorylation and subsequent activation of CREB. Although phosphorylation of CREB at Ser‐133 is necessary for the stimulation of transcriptional activity, it is not sufficient. Here we demonstrate that in mouse cortical neurons, inhibition of the Ca2+‐dependent protein phosphatase calcineurin by FK506 or cyclosporine A blocks CREB‐dependent gene expression induced by depolarization without inhibiting depolarization‐induced Ca2+ influx or CREB Ser‐133 phosphorylation. Over‐expression of a constitutively‐active allele of the transducer of regulated CREB activity could not bypass the requirement for calcineurin activity. Stimulation of a CRE‐luciferase reporter gene by depolarization was sensitive to FK506 throughout the entire time course of the transcriptional response, revealing that calcineurin activity is required to maintain CREB‐dependent transcription. Stimulation of CRE‐luciferase expression by forskolin and 8‐Br‐cAMP also required calcineurin activity. These results suggest that calcineurin functions as a critical determinant in shaping genome responses to CREB activation in cortical neurons.
Emerging functions of the calpain superfamily of cysteine proteases in neuroendocrine secretory pathways
Authors: Evans Joanne S. , Turner Mark D. 
Published: July 2007

AbstractThe first calpain protease was discovered over 40 years ago now, yet despite the vast amount of literature that has subsequently emerged detailing their involvement in the pathophysiology of a variety of human diseases, it is only in the last decade that calpain‐mediated actions along the secretory pathway have begun to emerge. However, the number of secretory pathway substrates identified and their diversity of function continues to grow. This review summarizes our current knowledge of calpain‐mediated mechanisms of action that are pertinent to synaptic vesicle assembly and budding, cytoskeletal organization, endosomal recycling, and exocytotic membrane fusion.
Prevalence of fimA genotypes of Porphyromonas gingivalis and periodontal health status in Chinese adults
Authors: Zhao L. , Wu Y.‐F. , Meng S. , Yang H. , OuYang Y.‐L. , Zhou X.‐D. 
Published: July 2007

Background and Objective:  Porphyromonas gingivalis fimbriae play a key role in colonization of the oral cavity. The fimA gene, which encodes fimbrillin (FimA), can be classified into six types (I–V and Ib) according to nucleotide sequence. In the present study, we investigated the relationship between the prevalence of P. gingivalis‐specific fimA genotypes and periodontal health status in Chinese adults.Material and Methods:  One‐hundred and fifteen patients with chronic periodontitis and 136 periodontally healthy adults were selected. P. gingivalis detection, determination of fimA genotypes, and the co‐existence of Actinobacillus actinomycetemcomitans and Tannerella forsythia with various fimA types, were assessed by the polymerase chain reaction. Odds ratios and 95% confidence intervals were calculated for associating the fimA‐specific genes with periodontitis.Results:  P. gingivalis was detected in 22.1% of healthy subjects and in 81.7% of the patients. A single fimA genotype was detected in most samples. In healthy adults, the most prevalent fimA genotype was type I (66.7%). However, type II was detected most frequently (43.6%) in the patient group, followed by type IV (30.9%). The frequency of co‐existing A. actinomycetemcomitans and T. forsythia was highest in type II fimA‐positive sites. Statistical analysis revealed that periodontitis was associated with occurrences of type I (odds ratio 0.97), Ib (odds ratio 13.26), II (odds ratio 36.62), III (odds ratio 4.57), IV (odds ratio 22.86) and V (odds ratio 1.19).Conclusion:  P. gingivalis type II followed by type IV were considered as disease‐associated strains that account for the pathogenesis of chronic periodontitis in Chinese adults.
Female Sexual Dysfunction in Urogenital Prolapse Surgery: Colposacropexy vs. Hysterocolposacropexy
Authors: Zucchi Alessandro , Costantini Elisabetta , Mearini Luigi , Fioretti Fabrizio , Bini Vittorio , Porena Massimo 
Published: July 2007

ABSTRACT

Introduction
Colposacropexy (CSP), with or without hysterectomy, is a valid technique for the repair of severe urogenital prolapse. For many years, uterine prolapse has represented an indication for hysterectomy, apart from the presence or absence of uterine disease and the patient's desires. Nevertheless, sparing the uterus is essential to women not only to have normal sexual functioning but to maintain physical and anatomical integrity as well.

Aim
To assess sexual function in a group of patients who underwent CSP or hysterocolposacropexy (HSP).

Materials and Methods
We enrolled 37 patients who underwent surgery for urogenital prolapse (15 HSP, mean age 53 years; 22 CSP, mean age 56 years). Based on a preliminary sexual history and sexual questionnaire, all patients were sexually active before surgery. At a mean follow-up of 39 months, we reassessed the patients using the Female Sexual Function Index (FSFI).

Main Outcome Measure
We considered sexual activity with a score of 30=good, 23–29=intermediate, and &lt;23=poor.

Results
In patients who underwent CSP and HSP, sexual activity was good in 13% and 26%, intermediate in 33% and 21%, and poor in 54% and 53%, respectively; considering also five patients who no longer had sexual activity postoperatively. Nevertheless, the statistical analysis, performed based on the data obtained from the FSFI questionnaire, showed that there were no significant differences between the two groups of points in terms of total score—CSP 21.1 (1.2–33.5) vs. HSP 22.8 (3.6–34.5)—and single domains (desire, arousal, lubrication, orgasm, satisfaction, and pain) (P =not significant).

Conclusions
Our data demonstrated no substantial differences regarding sexual activity in patients in which the uterus has been spared as opposed to those in whom it has been removed. Furthermore, in a small percentage of cases, surgery actually reduced regular sexual activity.