bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of positive mood induction on emotional processing in euthymic individuals with bipolar disorder and controls
Authors: Roiser J. , Farmer A. , Lam D. , Burke A. , O'Neill N. , Keating S. , Smith G. Powell , Sahakian B. , McGuffin P.
Published: August 2008

Background

Many studies have used negative mood induction techniques to investigate the effect of emotional state on cognitive performance but positive mood induction paradigms have been used less frequently. The objective of this study was to investigate the effect of positive mood induction on emotional processing in euthymic individuals with bipolar disorder (BD) and controls.

Method

Previously, we reported that positive mood induction using a novel technique based on feedback produced a longer-lasting effect in euthymic individuals with BD than controls (Farmer et al.2006). Here we report the effect of mood induction on two tests of emotional processing, the Affective Go/No-go test (AGNG) and the Cambridge Gamble task (CGT), on which BD patients in the manic phase differ in their performance from controls.

Results

Following positive mood induction, bipolar cases exhibited a positive emotional bias on the AGNG and performed more slowly than controls on the CGT, particularly when making more difficult decisions.

Conclusions

These data confirm that positive mood induction is more effective in individuals with BD than controls. They also suggest that alterations in decision making and attentional biases occur even with transient and subtle changes in mood in bipolar disorder.
Attention deficit hyperactivity disorder (ADHD): gender- and age-related differences in neurocognition
Authors: Bálint S. , Czobor P. , Komlósi S. , Mészáros Á. , Simon V. , Bitter I.
Published: August 2008

Background

Despite the growing recognition that the clinical symptom characteristics associated with attention deficit hyperactivity disorder (ADHD) persist into adulthood in a high proportion of subjects, little is known about the persistence of neurocognitive deficits in ADHD. The objective was twofold: (1) to conduct a meta-analysis of neuropsychological studies to characterize attentional performance in subjects with adult ADHD by examining differences in ADHDversusnormal control subjects; and (2) to investigate whether these differences vary as a function of age and gender.

Method

Twenty-five neuropsychological studies comparing subjects with adult ADHD and healthy controls were evaluated. Statistical effect size was determined to characterize the difference between ADHD and control subjects. Meta-regression analysis was applied to investigate whether the difference between ADHD and control subjects varied as a function of age and gender across studies.

Results

Tests measuring focused and sustained attention yielded an effect size with medium to large magnitude whereas tests of simple attention resulted in a small to medium effect size in terms of poorer attention functioning of ADHD subjectsversuscontrols. On some of the measures (e.g. Stroop interference), a lower level of attention functioning in the ADHD groupversusthe controls was associated with male gender.

Conclusions

Adult ADHD subjects display significantly poorer functioningversushealthy controls on complex but not on simple tasks of attention, and the degree of impairment varies with gender, with males displaying a higher level of impairment.
On the Selmer groups of abelian varieties over function fields of characteristic p > 0
Authors: OCHIAI TADASHI , TRIHAN FABIEN
Published: August 2008

We study a (p-adic) geometric analogue for abelian varieties over a function field of characteristic p of the cyclotomic Iwasawa theory and the non-commutative Iwasawa theory for abelian varieties over a number field initiated by Mazur and Coates respectively. We will prove some analogue of the principal results obtained in the case over a number field and we study new phenomena which did not happen in the case of number field case. We also propose a conjecture (Conjecture 1.6) which might be considered as a counterpart of the principal conjecture in the case over a number field.
A Systematic Approach to Identifying Protein-Ligand Binding Profiles on a Proteome Scale
Authors: Xie Li , Buchmeier Nancy , Xie Lei , Bourne Philip
Published: August 2008

Identification of protein-ligand interaction networks on a proteome scale is crucial to address a wide range of biological problems such as correlating molecular functions to physiological processes and designing safe and efficient therapeutics. We have developed a novel computational strategy to identify ligand binding profiles of proteins across gene families and applied it to predicting protein functions, elucidating molecular mechanisms of drug adverse effects, and repositioning safe pharmaceuticals to treat different diseases.
DISTRIBUTION OF CRAYFISH IN EUROPE AND SOME ADJOINING COUNTRIES
Authors: HOLDICH D. M.
Published: August 2008

The distribution of crayfish in Europe is examined using information from a variety of sources mainly for the last two decades. All European countries have at least one indigenous crayfish species (ICS), many with large stocks, and most countries in Western Europe have at least one non-indigenous crayfish species (NICS). Some species termed indigenous in certain countries may have been introduced in relatively recent times. However, the meaning of the term indigenous (native) varies between countries. NICS continue to expand their ranges and present a continued threat to ICS through competition and transmission of diseases, notably crayfish plague. The current high level of interest in crayfish means that many countries are monitoring their crayfish situation and, where necessary, taking steps to renew stocks of threatened indigenous species, some of which are apparently on the verge of extinction. A more regular monitoring programme for European crayfish as a whole is needed if the demise of indigenous species is to be prevented.
THE FRESHWATER CRAYFISH AUSTROPOTAMOBIUS PALLIPES (LEREBOULLET, 1858) IN LIGURIA, NW ITALY: IMPLICATIONS FOR MANAGEMENT AT THE REGIONAL LEVE
Authors: SALVIDIO S. , MORI M. , LATTES A. , GALLI L. , ARILLO A.
Published: August 2008

Since 1990, field surveys have been undertaken in Liguria to assess the distribution and status of Austropotamobius pallipes populations. In this region, crayfish stocks were found in three bioclimatic regions: Alpine, Mediterranean and Continental. Although epidemic diseases and invasive alien crayfish have been recorded, modifications of freshwater habitats have to be considered as the most significant threats to native crayfish stocks. Regarding management, the Regional Administration of Liguria proposed 18 Sites of Community Importance (SCI) containing crayfish populations, in the framework of the Habitats Directive (92/43/EEC). Since public managers need to take informed decisions in land-use management and conservation a numeric biodiversity map, composed by a georeferred database connected to a geographic information system (GIS), has been implemented. This regional system is composed by 22 different layers containing all the available information about the location of species and habitats of conservation interest. This system is now routinely used by regional administrators in environmental impact assessment. Finally, emphasis is placed on the need of promoting research programmes on the long-term monitoring of crayfish populations.
DISTRIBUTION AND HABITAT REQUIREMENTS OF THE WHITE-CLAWED CRAYFISH, AUSTROPOTAMOBIUS PALLIPES, IN A STREAM FROM THE PAYS DE LOIRE REGION, FRANCE: AN EXPERIMENTAL AND DESCRIPTIVE STUDY
Authors: BROQUET T. , THIBAULT M. , NEVEU A.
Published: August 2008

A population of white-clawed crayfish (Austropotamobius pallipes) was studied from January to October 2000 in a stream from the Pays de Loire region (Western France). An experimental modification of habitat was performed in four stream sections by providing refuges for crayfish, followed by a regular survey of population dynamics in these areas. The crayfish distribution along the brook was studied in relation to several parameters, including water quality, current speed, brook depth and presence of refuges for crayfish. Presence of hiding places was the only habitat parameter correlated with crayfish distribution along the stream whereas colonization process in modified sections was determined by sun exposure and current speed conditions. Despite a presumably high growth rate and its ability to reach locally important densities, the population appeared to be fragmented.
INFESTATION RATE OF BRANCHIOBDELLIDS IN AUSTROPOTAMOBIUS PALLIPES ITALICUS FROM A STREAM OF CENTRAL ITALY: PRELIMINARY RESULTS
Authors: GHERARDI F. , CENNI F. , CRUDELE G. , MORI M.
Published: August 2008

Species identity, infestation rate and distribution over the host body of branchiobdellids (Annelida, Clitellata) have been analysed in an Austropotamobius pallipes italicus population from the National Park of the Foreste Casentinesi, Monte Falterona and Campigna (central Italy). Branchiobdella italica - the nearly unique species present in our samples - did not differ in its occurrence among the size classes of its host, while female crayfish showed a significantly higher infestation rate than the other sex. Branchiobdellids were mostly found on gill chambers and cephalothorax base, and only in the case of larger crayfish and males did they occupy other body areas.
ROUNDTABLE SESSION 2B: NATIONAL INTERACTIONS BETWEEN NON-INDIGENOUS AND INDIGENOUS CRAYFISH SPECIES
Authors: GHERARDI F. , SMIETANA P. , LAURENT P.
Published: August 2008

The main object of the present essay is to summarise some aspects underlying the interactions between non-indigenous (NICS) and indigenous (ICS) crayfish species. The discussion has been also extended to the effects exercised by NICS on the natural habitats they occupy. While doing research on the dyads NICS/ICS, one starting point is to extrapolate common traits that make NICS good invaders from the analysis of their biology, ecology and ethology and the comparison with indigenous species. A subsequent step is to switch attention to the understanding of the characteristics that make ecosystems less vulnerable to invasions and then to analyse both the complex interactions of invaders and target communities and the negative and positive impacts exerted by NICS on the occupied habitats. Examples from Sweden, Britain, and Italy have shown that NICS can replace the native species by a combination of several interacting mechanisms. Besides the transmission of the crayfish plague fungus, mechanisms into action include mostly competitive interference, but also diverse life history traits, recruitment failure, differential susceptibility to predation, and reproductive interference. It has been claimed that invasion theory is full of rules of thumb that, having no precise predictive powers, are thus useless to guide reliable public policy. The solution of the prediction problem requires an in-depth study of every potential invader and target community, trespassing the boundaries among disciplines and having a look at crayfish as a whole and not a single entity. The expectation is thus the return to precise and clear empirical generalisations that can be most useful to develop management strategies.
DESCRIPTION DE LA ZOOÉPIBIOSE DE L’ÉCREVISSE SIGNAL (PACIFASTACUS LENIUSCULUS, DANA) EN ASTACICULTURE
Authors: CUELLAR M. C. , GARCIA-CUENCA I. , FONTANILLAS J. C.
Published: August 2008

Des recherches ont été effectuées concernant la zooépibiose de l’écrevisse signal (Pacifastacus leniusculus, D.), provenant d’un centre d’astaciculture espagnol, au cours de la période 1997-1998.

Les organismes épibiotiques dominants trouvés sur l’exosquelette appartiennent aux groupes zoologiques d’Invertébrés suivants : Mastigophora (Bodo), Cilliophora (Stentor, Epistylis, Zoothamnium, Acineta), Turbelaria (Temnocephala), Rotifera (Brachionus), Annelida (Branchiobdella), Acarina (Hygrobates) et Ostracode (Eucypris ou Enthocytera), on souligne le nombre élevé de Branchiobdellides de l’espèce Branchiobdella instabilia M., dont les quantités minimum et maximum, en mâles et femelles, oscillent de 12 à 139 et de 7 à 130, respectivement.

Les hyperbranchiobdelloses provoquent des automutilations, des décollements des pinces et autres appendices, des mues anormales, des lésions cuticulaires, de l’hémocytopénie et des changements éthologiques.

Les colonisations maximales d’Ostracodes de l’espèce Eucypris virens, J.O., Enthocytera heterodonta, R., dans les poches d’incubation des femelles donnent lieu à une coloration rougeâtre des oeufs et à leur perte postérieure.

Compte tenu de leur nombre limité et de la période d’épibiose, les genres des sous-types Mastigophora, Ciliophora, Turbelaria, Rotifera et Arachnida ne représentent aucun danger pour les écrevisses.

En ce qui concerne la zooépibiose associée aux appendices et aux régions du corps des écrevisses du Pacifique, les chélipèdes ou pinces constituent le substrat où se place de préférence le genre Branchiobdella ; le céphalothorax sert de support à tous les groupes taxonomiques d’épibiontes identifiés.
APPROCHE MORPHOLOGIQUE DE L’ÉCREVISSE ASTACUS ASTACUS L. 1758 ASSOCIÉE À L’IMAGERIE (TOMOSCANNER ET ÉCHO-DOPPLER) ET AUX TECHNIQUES IMMUNOHISTOCHIMIQUES
Authors: BENYAHIA T. M. , BELABBAS A. M. , BENSAID H. , AMRANI M. , BENJELLOUN A. , SEMLALI A.
Published: August 2008

Après avoir souligné, d’une manière concrète, les difficultés de la dissection et le repérage par les méthodes classiques, nous avons essayé dans ce travail d’aborder l’apport de la macroscopie indirecte de l’animal grâce à la radiologie (échographie, tomoscanner, lavement baryté) afin de vérifier les donnés anatomiques sur l’écrevisse à pattes rouges, complété par des techniques microscopiques.

Dans notre travail, l’adaptation pour l’écrevisse de techniques nouvelles de radiologie (tomoscanner et échographie) complétées par les études d’histologie (colorations et immunohistochimie) ont permis de se rendre compte des possibilités qu’elles offrent pour l’exploration dynamique et le repérage précis des organes et pour le diagnostic de maladies histopathologiques et ceci sans porter atteinte à l’animal.

Le but de cette approche est de mettre au point des moyens d’investigation sur l’animal vivant pour mieux cerner les éventuels états pathologiques touchant surtout ses organes profonds et contribuer ainsi à préserver cette espèce menacée par la pollution des milieux astacicoles et par la sécheresse persistante que connaît le Maroc ces dernières années.
GENETIC DIFFERENTIATION BETWEEN NOBLE CRAYFISH, ASTACUS ASTACUS (L.), POPULATIONS DETECTED BY MICROSATELLITE LENGTH VARIATION IN THE RDNA ITS1 REGION
Authors: EDSMAN L. , FARRIS J. S. , KÄLLERSJÖ M. , PRESTEGAARD T.
Published: August 2008

The Internal Transcribed Spacer (ITS) region of the nuclear ribosomal repeat was investigated in the search for a suitable genetic marker for population studies of the noble crayfish Astacus astacus (L.). DNA sequencing revealed the presence of two microsatellite insertions in ITS1. By designing highly specific PCR primers, adjacent to one of the insertions, we were able to use fragment analysis to explore the variation of the insertion in 642 specimens from 17 populations of crayfish from Sweden and former Yugoslavia. A new statistical test, the Population Divergence Test, was developed to assess statistical significance of divergence between populations. This test does not assume Mendelian inheritance. Our results demonstrate that different populations often produce characteristic fragment patterns, and that most, but not all, populations are genetically distinct, with high significance. The populations that cannot be significantly differentiated are situated in close geographic proximity to each other and belong to the same main river system, probably reflecting that these populations have had recent contact and that gene flow has occurred.
Modelling the impact of possible snowpack emissions of O(3P) and NO2 on photochemistry in the South Pole boundary layer
Authors: Hamer P. D. , Shallcross D. E. , Yabushita A. , Kawasaki M.
Published: August 2008

Environmental context. The study of surface photochemical ozone production on the Antarctic continent has direct relevance to climate change and general air quality and is scientifically noteworthy given the otherwise pristine nature of this environmental region. The identification of possible direct ozone emissions from snow surfaces and their contribution to the already active photochemical pollution present there represents a unique physical phenomenon. This process could have wider global significance for other snow-covered regions and therefore for global climate change.
Abstract. O(3P) emissions due to photolysis of nitrate were recently identified from ice surfaces doped with nitric acid. O(3P) atoms react directly with molecular oxygen to yield ozone. Therefore, these results may have direct bearing on photochemical activity monitored at the South Pole, a site already noted for elevated summertime surface ozone concentrations. NO2 is also produced via the photolysis of nitrate and the firn air contains elevated levels of NO2, which will lead to direct emission of NO2. A photochemical box model was used to probe what effect O(3P) and NO2 emissions have on ozone concentrations within the South Pole boundary layer. The results suggest that these emissions could account for a portion of the observed ozone production at the South Pole and may explain the observed upward fluxes of ozone identified there.
Morphometric study of Euchiton traversii complex (Gnaphalieae: Asteraceae)
Authors: Flann Christina , Breitwieser Ilse , Ward Josephine M. , Walsh Neville G. , Ladiges Pauline Y.
Published: August 2008

A morphometric study was undertaken into alpine and subalpine species of Euchiton Cass. (Gnaphalieae: Asteraceae) in the Euchiton traversii species complex in south-eastern Australia and New Zealand. Phenetic analysis of both field-collected and herbarium specimens resolved the following six taxa included: Euchiton traversii (Hook.f.) Holub, Euchiton argentifolius (N.A.Wakef.) Anderb., Euchiton lateralis (C.J.Webb) Breitw. & J.M.Ward, Argyrotegium mackayi (Buchanan) J.M.Ward & Breitw., Argyrotegium fordianum (M.Gray) J.M.Ward & Breitw. and Argyrotegium poliochlorum (N.G.Walsh) J.M.Ward & Breitw. The results support the segregation of the genus Argyrotegium J.M.Ward & Breitw. from Euchiton. E. argentifolius is distinct from E. traversii, but conspecific with A. mackayi. E. lateralis is present in Tasmania as well as New Zealand. The distribution of Australian E. traversii is redefined to mainland alpine regions with a few rare occurrences in Tasmania. Australian E. traversii was shown to be similar to its New Zealand counterparts. Differences between E. lateralis and E. traversii were clarified. A. fordianum and A. poliochlorum are distinct species and their transfer to Argyrotegium is supported.
The intrinsic conformational propensities of the 20 naturally occurring amino acids and reflection of these propensities in proteins
Authors: Beck David A. C. , Alonso Darwin O. V. , Inoyama Daigo , Daggett Valerie
Published: August 2008

Here, we compare the distributions of main chain (Φ,Ψ) angles (i.e., Ramachandran maps) of the 20 naturally occurring amino acids in three contexts: (
i
) molecular dynamics (MD) simulations of Gly-Gly-X-Gly-Gly pentapeptides in water at 298 K with exhaustive sampling, where X = the amino acid in question; (
ii
) 188 independent protein simulations in water at 298 K from our Dynameomics Project; and (
iii
) static crystal and NMR structures from the Protein Data Bank. The GGXGG peptide series is often used as a model of the unstructured denatured state of proteins. The sampling in the peptide MD simulations is neither random nor uniform. Instead, individual amino acids show preferences for particular conformations, but the peptide is dynamic, and interconversion between conformers is facile. For a given amino acid, the (Φ,Ψ) distributions in the protein simulations and the Protein Data Bank are very similar and often distinct from those in the peptide simulations. Comparison between the peptide and protein simulations shows that packing constraints, solvation, and the tendency for particular amino acids to be used for specific structural motifs can overwhelm the “intrinsic propensities” of amino acids for particular (Φ,Ψ) conformations. We also compare our helical propensities with experimental consensus values using the host–guest method, which appear to be determined largely by context and not necessarily the intrinsic conformational propensities of the guest residues. These simulations represent an improved coil library free from contextual effects to better model intrinsic conformational propensities and provide a detailed view of conformations making up the “random coil” state.
Role of furin in granular acidification in the endocrine pancreas: Identification of the V-ATPase subunit Ac45 as a candidate substrate
Authors: Louagie Els , Taylor Neil A. , Flamez Daisy , Roebroek Anton J. M. , Bright Nicholas A. , Meulemans Sandra , Quintens Roel , Herrera Pedro L. , Schuit Frans , Van de Ven Wim J. M. , Creemers John W. M.
Published: August 2008

Furin is a proprotein convertase which activates a variety of regulatory proteins in the constitutive exocytic and endocytic pathway. The effect of genetic ablation of
fur
was studied in the endocrine pancreas to define its physiological function in the regulated secretory pathway.
Pdx1-Cre
/loxP furin KO mice show decreased secretion of insulin and impaired processing of known PC2 substrates like proPC2 and proinsulin II. Both secretion and PC2 activity depend on granule acidification, which was demonstrated to be significantly decreased in furin-deficient β cells by using the acidotrophic agent 3-(2,4-dinitroanilino)-3′amino-
N
-methyldipropylamine (DAMP). Ac45, an accessory subunit of the proton pump V-ATPase, was investigated as a candidate substrate. Ac45 is highly expressed in islets of Langerhans and furin was able to cleave Ac45
ex vivo
. Furthermore, the exact cleavage site was determined. In addition, reduced regulated secretion and proinsulin II processing could be obtained in the insulinoma cell line βTC3 by downregulation of either furin or Ac45. Together, these data establish an important role for furin in regulated secretion, particularly in intragranular acidification most likely due to impaired processing of Ac45.
Evolution exacerbates the paradox of the plankton
Authors: Shoresh Noam , Hegreness Matthew , Kishony Roy
Published: August 2008

Can biodiversity evolve and persist in a uniform environment? This question is at the heart of the plankton paradox: in the natural world we observe many species sharing few resources, whereas the principle of competitive exclusion would lead us to expect that only a few species could coexist in such circumstances. To bridge the gap between theory and observation, previous studies have shown that the maximum number of species that can stably coexist is equal to the number of essential resources and that even more species can coexist out of equilibrium. These studies were viewed as a significant step toward a resolution of the paradox. Evolutionary dynamics, however, have been studied in this context only in limited cases, and it is largely unknown how mutations impact ecologically stable multispecies states, and whether large species consortia can spontaneously evolve. In the present study we introduce evolution to the standard ecological model of competition for essential resources. Combining numeric and analytic approaches, we find that ecologically stable species communities are severely destabilized by long-term evolutionary dynamics. Moreover, the number of species in spontaneously evolved consortia is much lower than the number of available resources. Contrary to expectations based on studies of two resources, these limits on biodiversity are not results of the occasional emergence of superspecies, superior to all competitors; nor are they alleviated by the inclusion of tradeoffs in resource utilization. Rather, we show that it is an accelerated depletion of limiting resources, combined with the essentiality of resources to all species, that leads invariably to catastrophic extinctions.
Crystal structures of fibronectin-binding sites from
Staphylococcus aureus
FnBPA in complex with fibronectin domains
Authors: Bingham Richard J. , Rudiño-Piñera Enrique , Meenan Nicola A. G. , Schwarz-Linek Ulrich , Turkenburg Johan P. , Höök Magnus , Garman Elspeth F. , Potts Jennifer R.
Published: August 2008

Staphylococcus aureus
can adhere to and invade endothelial cells by binding to the human protein fibronectin (Fn). FnBPA and FnBPB, cell wall-attached proteins from
S. aureus
, have multiple, intrinsically disordered, high-affinity binding repeats (FnBRs) for Fn. Here, 30 years after the first report of
S. aureus
/Fn interactions, we present four crystal structures that together comprise the structures of two complete FnBRs, each in complex with four of the N-terminal modules of Fn. Each ≈40-residue FnBR forms antiparallel strands along the triple-stranded β-sheets of four sequential F1 modules (
2–5
F1) with each FnBR/
2–5
F1 interface burying a total surface area of ≈4,300 Å
2
. The structures reveal the roles of residues conserved between
S. aureus
and
Streptococcus pyogenes
FnBRs and show that there are few linker residues between FnBRs. The ability to form large intermolecular interfaces with relatively few residues has been proposed to be a feature of disordered proteins, and
S. aureus
/Fn interactions provide an unusual illustration of this efficiency.
Competition between cryptic species explains variations in rates of lineage evolution
Authors: Alizon Samuel , Kucera Michal , Jansen Vincent A. A.
Published: August 2008

Gradual evolution is a common phenomenon in the fossil record of marine microplankton, yet no theoretical model has so far been presented to explain the observed pattern of unidirectionality in trait evolution lasting over tens of millions of generations. Recent molecular genetic data show that the majority of microfossil-producing plankton groups harbors substantial cryptic diversity. Here, we examine the effect of cryptic diversity on apparent rates of lineage evolution. By using a theoretical approach, we show that under resource competition, an increasing number of sibling species within a hypothetical lineage leads to an exponential slowdown of the apparent rate of evolution. This mechanism explains both the remarkable variation in apparent rates of evolution observed in marine plankton, as well as the presence of long gradual evolutionary trends.
Stochastic hybrid modeling of DNA replication across a complete genome
Authors: Lygeros J. , Koutroumpas K. , Dimopoulos S. , Legouras I. , Kouretas P. , Heichinger C. , Nurse P. , Lygerou Z.
Published: August 2008

DNA replication in eukaryotic cells initiates from hundreds of origins along their genomes, leading to complete duplication of genetic information before cell division. The large number of potential origins, coupled with system uncertainty, dictates the need for new analytical tools to capture spatial and temporal patterns of DNA replication genome-wide. We have developed a stochastic hybrid model that reproduces DNA replication throughout a complete genome. The model can capture different modes of DNA replication and is applicable to various organisms. Using genome-wide data on the location and firing efficiencies of origins in the fission yeast, we show how the DNA replication process evolves during S-phase in the presence of stochastic origin firing. Simulations reveal small regions of the genome that extend S-phase to three times its reported duration. The low levels of late replication predicted by the model are below the detection limit of techniques used to measure S-phase length. Parameter sensitivity analysis shows that increased replication fork speeds genome-wide, or additional origins are not sufficient to reduce S-phase to its reported length. We model the redistribution of a limiting initiation factor during S-phase and show that it could shorten S-phase to the reported duration. Alternatively, S-phase may be extended, and what has traditionally been defined as G2 may be occupied by low levels of DNA synthesis with the onset of mitosis delayed by activation of the G2/M checkpoint.
Secular Trends in Candidemia-Related Hospitalization in the United States, 2000–2005
Authors: Zilberberg Marya D. , Shorr Andrew F. , Kollef Marin H.
Published: August 2008

In the United States, from January 1, 2000, through December 31, 2005, the incidence of candidemia-related hospitalization per 100,000 population rose by 52%, from 3.65 to 5.56 cases; and the incidence per 1,000 hospitalizations rose by 49%, from 0.28 to 0.42 cases. The proportion of all candidemia-related hospitalizations in which candidemia was the principal diagnosis remained stable at approximately 14%.
Sea lampreyPetromyzon marinus: an exception to the rule of homing in anadromous fishes
Authors: Waldman John , Grunwald Cheryl , Wirgin Isaac
Published: August 2008

Anadromous fishes are believed to make regular circuits of migration in the sea before homing to their natal rivers. Sea lampreyPetromyzon marinusis an anadromous fish that is an exception to this life-history pattern. It also differs from other anadromous fishes in that its adult phase is parasitic, a feeding strategy that should make homing problematic for lamprey cohorts that become widely dispersed through transport by the diverse hosts they parasitize. We sequenced a portion of the mitochondrial DNA control region from sea lampreys collected from 11 North American east coast rivers to test for genetic evidence of homing. There were no significant differences (Χ2=235.1,p=0.401) in haplotype frequencies among them, with almost 99 per cent of haplotypic diversity occurring within populations. These findings, together with concordant genetic results from other geographical regions and ancillary information on pheromonal communication, suggest that sea lamprey does not home but rather exhibits regional panmixia while using a novel ‘suitable river’ strategy to complete its life cycle.
Testing the island effect in adaptive radiation: rates and patterns of morphological diversification in Caribbean and mainlandAnolislizards
Authors: Pinto Gabriel , Mahler D. Luke , Harmon Luke J , Losos Jonathan B
Published: August 2008

Many of the classic examples of adaptive radiation, including CaribbeanAnolislizards, are found on islands. However,Anolisalso exhibits substantial species richness and ecomorphological disparity on mainland Central and South America. We compared patterns and rates of morphological evolution to investigate whether, in fact, islandAnolisare exceptionally diverse relative to their mainland counterparts. Quite the contrary, we found that rates and extent of diversification were comparable—Anolisadaptive radiation is not an island phenomenon. However, mainland and Caribbean anoles occupy different parts of morphological space; in independent colonizations of both island and mainland habitats, island anoles have evolved shorter limbs and better-developed toe pads. These patterns suggest that the two areas are on different evolutionary trajectories. The ecological causes of these differences are unknown, but may relate to differences in predation or competition among mainland and island communities.
A fast and accurate computational approach to protein ionization
Authors: Spassov Velin Z. , Yan Lisa
Published: August 2008

We report a very fast and accurate physics‐based method to calculate pH‐dependent electrostatic effects in protein molecules and to predict the pK values of individual sites of titration. In addition, a CHARMm‐based algorithm is included to construct and refine the spatial coordinates of all hydrogen atoms at a given pH. The present method combines electrostatic energy calculations based on the Generalized Born approximation with an iterative mobile clustering approach to calculate the equilibria of proton binding to multiple titration sites in protein molecules. The use of the GBIM (Generalized Born with Implicit Membrane) CHARMm module makes it possible to model not only water‐soluble proteins but membrane proteins as well. The method includes a novel algorithm for preliminary refinement of hydrogen coordinates. Another difference from existing approaches is that, instead of monopeptides, a set of relaxed pentapeptide structures are used as model compounds. Tests on a set of 24 proteins demonstrate the high accuracy of the method. On average, the RMSD between predicted and experimental pK values is close to 0.5 pK units on this data set, and the accuracy is achieved at very low computational cost. The pH‐dependent assignment of hydrogen atoms also shows very good agreement with protonation states and hydrogen‐bond network observed in neutron‐diffraction structures. The method is implemented as a computational protocol in Accelrys Discovery Studio and provides a fast and easy way to study the effect of pH on many important mechanisms such as enzyme catalysis, ligand binding, protein–protein interactions, and protein stability.
Effects of target concentration infusion of propofol and tracheal intubation on QTc interval*
Authors: Kim D. H. , Kweon T. D. , Nam S. B. , Han D. W. , Cho W. Y. , Lee J. S.
Published: August 2008

This study was designed to evaluate the effect of target controlled infusion of propofol on QTc interval and tracheal intubation. Twenty‐five unpremedicated, ASA class I or II patients were selected and target concentration infusion of propofol at 5 μg.ml−1 was used throughout the study. The QTc interval was measured before anaesthetic induction (baseline, T1), 10 min after propofol infusion (T2), immediately after tracheal intubation (T3), and 1 min after tracheal intubation (T4). The QTc interval increased significantly at 10 min after the propofol infusion started compared to baseline (p = 0.003). After tracheal intubation, the QTc interval was further increased when compared to that at T2 (p < 0.0001). The increased QTc interval was within normal limit and no patient had an arrhythmia. In conclusion, although statistically significant, the increase in QTc interval was too small to be clinically significant during propofol infusion. However, the combination of propofol and tracheal intubation must be used carefully in patients with prolonged QTc interval.
Evaluation of bag‐valve‐mask ventilation in simulated toxic environments*
Authors: Brinker A. , Stratling W. M. , Schumacher J.
Published: August 2008

Bag‐valve‐mask ventilation is a key component of life support, but only one handheld resuscitator is designed to operate in contaminated or toxic atmospheres. Following Institutional Review Board approval we determined the efficacy of this device. Twenty anaesthetists ventilated a modified manikin, either with or without a combination filter attached to the resuscitator inlet. The mean (SD) maximum minute volume achieved without the filter was 9.3 (3.1) l.min‐1. Use of the inlet filtration system reduced the maximum minute volume significantly to 6.4 (2.2) l.min−1 (reduction of 30%, p = 0.0017). The achieved maximum minute volumes ranged from 13.4 to 4 l.min−1 in the controls and from 9.5 to 3 l.min−1 in the filter group. The delay in refilling of the self‐inflatable bag may have resulted in reduced achievable minute volumes. The range of the maximum minute volumes in both groups highlights the need for continuous bag‐valve‐mask ventilator training.
The effect of temperature on bougies: a photographic and manikin study*
Authors: Mingo O. , Suaris P. , Charman S. , Ferguson C. , Patel A.
Published: August 2008

We investigated the effect of temperature on single use and reuseable bougies. In a photographic study, three bougies (Portex® Venn reuseable (R), Portex single use (S) and Breathesafe™ single use (B)) were exposed to increasing temperatures and sequential photographs were taken of the bougies uncoiling from a preformed curve. Bougie type was associated with rate of uncoiling, type R maintaining its curve the longest but changing temperature did not affect this. In a randomised cross‐over manikin study, 16 anaesthetists attempted to pass two bougies (Portex reuseable (R) and Portex single use (S)) at three temperatures (10, 20 and 30 °C) into the trachea of a manikin. Type R was significantly associated with higher success rate of tracheal placement compared to type S. Change of temperature was significant with success rate increasing with lower temperature. The odds of success at 10 °C was six times that at 30 °C (OR (95%) 6.7 (1.7, 25.7)). We concluded that both bougies performed best at 10 °C.
Multiple organ failure and severe bone marrow dysfunction in two 18 year‐old Caucasian patients: Epstein–Barr virus and the haemophagocytic syndrome
Authors: Berry P. A. , Bernal W. , Pagliuca A. , Sizer E. , Salisbury J. R. , Wendon J. A. , Auzinger G.
Published: August 2008

Haemophagocytic lymphohistiocytosis secondary to viral infection is an unusual but well recognised cause of bone marrow dysfunction and multiple organ failure in young patients. Two 18 year‐old patients were admitted to a tertiary liver unit with features of acute liver failure, cardio‐respiratory collapse and pancytopenia. Serological tests and bone marrow examination with in‐situ hybridisation revealed severe acquired haemophagocytic lymphohistiocytosis secondary to acute Epstein–Barr virus infection. Both patients died despite full supportive therapy; the first due to pulmonary haemorrhage, the second due to acute respiratory distress syndrome refractory to high frequency oscillatory ventilation. The clinical spectrum, diagnostic features and current evidence based recommendations for treatment of this condition are explored. The diagnosis of haemophagocytic lymphohistiocytosis should be considered in young patients with marked bone marrow dysfunction and multiple organ failure. Further research into appropriate therapy for patients with acute severe forms of the disease who require intensive organ support is required.
Posterior reversible encephalopathy syndrome: a report of a case with atypical features
Authors: Pratap J. N. , Down J. F.
Published: August 2008

We report a case of a young woman presenting with profound depression of consciousness and intra‐uterine death in the late stages of an unbooked pregnancy. She proceeded to develop features of cardiovascular, renal, hepatic and haematological failures. The patient was challenging to manage in view of uncertainty regarding the underlying cause, and required multidisciplinary consultation. A diagnosis was subsequently made of posterior reversible encephalopathy syndrome in the context of pre‐eclampsia. We review the typical presentation and wide‐ranging associations of this recently described clinico‐neuroradiological syndrome, and look at how appropriate management may lead to rapid resolution of its often life‐threatening features. We highlight the importance to anaesthetists and critical care physicians of recognising even atypical cases such as this one in view of key differences in management from similarly presenting conditions.
No difference between strontium ranelate (SR) and calcium/vitamin D on bone turnover markers in women with established osteoporosis previously treated with teriparatide: a randomized controlled trial
Authors: Anastasilakis Athanasios D. , Goulis Dimirtios G. , Polyzos Stergios A. , Gerou Spiridon , Ballaouri Iris , Efstathiadou Zoe , Kita Marina , Avramidis Avraam
Published: August 2008

Objective   To evaluate the effect of strontium ranelate (SR) on bone turnover markers in women with established osteoporosis previously treated with teriparatide (TPTD – recombinant human PTH 1–34).

Design   patients: Twenty‐two postmenopausal Caucasian women (aged 65·7 ± 1·7 years) with established osteoporosis previously treated with TPTD 20 µg daily for 18 months were randomly assigned to receive either SR (SR group, n = 11) or calcium and vitamin D (control group, n = 11).

Measurements   Blood samples for serum N‐terminal propeptide of type 1 collagen (P1NP), C‐terminal telopeptide of type 1 collagen (CTx) and total alkaline phosphatase (ALP) were obtained from all women before (pre‐TPTD) and after (post‐TPTD) TPTD administration, as well as 6 months after SR or calcium/vitamin D administration (post‐SR/Ca).

Results   Serum P1NP, CTx and total ALP increased significantly after TPTD treatment and decreased at the end of the study in both SR and control groups, with no difference between them.

Conclusions   SR following TPTD administration acts predominantly as an antiresorptive agent with no evidence of additional osteoanabolic action. In this setting, SR is not more effective than Ca/vitamin D as far as bone turnover markers are concerned.
The Pro12Ala PPARγ gene polymorphism: possible modifier of the activity and severity of thyroid‐associated orbitopathy (TAO)
Authors: Alevizaki Maria , Mantzou Emily , Cimponeriu Adriana , Saltiki Katerina , Philippou George , Wiersinga Wilmar
Published: August 2008

Objective  The PPARγ transcription factor, is involved in both adipogenesis and inflammation, which have been implicated in the pathogenesis of thyroid‐associated orbitopathy (TAO). The aim of this study was to explore the possibility that the Pro12Ala polymorphism of the PPARγ gene, associated with a modified transcriptional activity, might be affecting the severity of TAO.

Subjects and design   We studied two cohorts of patients with Graves’ disease (GD): Group 1 comprised 172 patients of Dutch ethnic origin with TAO, who attended the outpatients’ clinic, Department of Endocrinology and Orbital Centre of the Academic Medical Centre, Amsterdam. Group 2 comprised 93 consecutive patients with GD of Greek ethnic origin, who did not have TAO. In group 1, exophthalmometry measurements, lid oedema, diplopia (n = 172) and clinical activity score (CAS) (n = 110), always assessed by the same group of three investigators, were recorded. Autoantibody levels were measured.

Results  Allele frequency was 11·5%. There was no difference in the distribution of the polymorphism between GD patients with and without TAO. Among group 1 patients proptosis was significantly lower in Pro12Ala carriers (20·1 ± 3·3 vs. 22·1 ± 3·1, P = 0·003, t‐test). PPARγ polymorphism carriers had lower TSH‐Rab levels (mean rank 61·8 vs. 83·2, P = 0·015) and lower CAS (available in 110 patients) (mean rank 38·9 vs. 55·4, P = 0·022, M–W‐test). The frequency of the polymorphism decreased with increasing CAS (P = 0·023 linear by linear association). Multivariate analysis (step) showed that the association of either proptosis or CAS with the PPARγ gene variant remained significant when age, smoking and TSH‐Rab levels were taken into account (P < 0·01).

Conclusions  The distribution of the Pro12Ala PPARγ gene polymorphism is equally present in patients with GD with or without TAO. Among patients with TAO this polymorphism is associated with less‐severe and less‐active disease.
Relationships between deforestation, riparian forest buffers and benthic macroinvertebrates in neotropical headwater streams
Authors: LORION CHRISTOPHER M. , KENNEDY BRIAN P.
Published: August 2008

1. Few studies have evaluated the effectiveness of riparian buffers in the tropics, despite their potential to reduce the impacts of deforestation on stream communities. We examined macroinvertebrate assemblages and stream habitat characteristics in small lowland streams in southeastern Costa Rica to assess the impacts of deforestation on benthic communities and the influence of riparian forest buffers on these effects. Three different stream reach types were compared in the study: (i) forested reference reaches, (ii) stream reaches adjacent to pasture with a riparian forest buffer at least 15 m in width on both banks and (iii) stream reaches adjacent to pasture without a riparian forest buffer.

2. Comparisons between forest and pasture reaches suggest that deforestation, even at a very local scale, can alter the taxonomic composition of benthic macroinvertebrate assemblages, reduce macroinvertebrate diversity and eliminate the most sensitive taxa. The presence of a riparian forest buffer appeared to significantly reduce the effects of deforestation on benthic communities, as macroinvertebrate diversity and assemblage structure in forest buffer reaches were generally very similar to those in forested reference reaches. One forest buffer reach was clearly an exception to this pattern, despite the presence of a wide riparian buffer.

3. The taxonomic structure of macroinvertebrate assemblages differed between pool and riffle habitats, but contrasts among the three reach types in our study were consistent across the two habitats. Differences among reach types also persisted across three sampling periods during our 15‐month study.

4. Among the environmental variables we measured, only stream water temperature varied significantly among reach types, but trends in periphyton abundance and stream sedimentation may have contributed to observed differences in macroinvertebrate assemblage structure.

5. Forest cover was high in all of our study catchments, and more research is needed to determine whether riparian forest buffers will sustain similar functions in more extensively deforested landscapes. Nevertheless, our results provide support for Costa Rican regulations protecting riparian forests and suggest that proper riparian management could significantly reduce the impacts of deforestation on benthic communities in tropical streams.
Isolated remnant or recent introduction? Estimating the provenance of Yellingbo Leadbeater's possums by genetic analysis and bottleneck simulation
Authors: HANSEN BIRGITA D. , TAYLOR ANDREA C.
Published: August 2008

Effective conservation management requires that genetically divergent populations potentially harbouring important local adaptations be identified and maintained as separate management units. In the case of the endangered Australian Leadbeater's possum (Gymnobelideus leadbeateri), an arboreal marsupial endemic to Victoria, uncertainty over the evolutionary origin of a potentially important extant wild population recently discovered in atypical habitat (lowland swamp) at Yellingbo is hampering such efforts. The population is rumoured to be a recent introduction. Microsatellite allele frequencies at Yellingbo differed substantially from those in sampled populations in montane ash forest (FST between 0.23 and 0.36), and Bayesian clustering analyses of genotypes strongly separated them (K = 2). We conducted a suite of bottlenecking tests which all indicated that Yellingbo had undergone a recent reduction in size. The extent to which the distinctiveness of Yellingbo animals might be expected solely through bottlenecking associated with a recent introduction, was tested by simulating population–history scenarios seeded with genotypes from candidate wild and captive sources. No bottleneck scenario reproduced anything approaching the genetic distinction of the Yellingbo population, with all structure analyses placing Yellingbo in a separate cluster to simulated populations (K = 2, minimum FST = 0.13). These results suggest that Yellingbo does not share recent ancestry with other extant populations and instead may be a remnant of an otherwise extinct gene pool. Importantly, this may include genes involved in adaptation to a lowland swamp environment, substantially adding to the conservation importance of this population, and suggesting that separate management may be prudent until evidence suggests otherwise.