bluuebunny/crossref_metadata_2025 huggingface dataset:
Decomposing phylogenetic entropy into
α
,
β
and
γ
components
Authors: Mouchet Maud A. , Mouillot David
Published: October 2010

Measuring the phylogenetic diversity of communities has become a key issue for biogeography and conservation. However, most diversity indices that rely on interspecies phylogenetic distances may increase with species loss and thus violate the principle of weak monotonicity. Moreover, most published phylogenetic diversity indices ignore the abundance distribution along phylogenetic trees, even though lineage abundances are crucial components of biodiversity. The recently introduced concept of phylogenetic entropy overcomes these limitations, but has not been decomposed across scales, i.e. into
α
,
β
and
γ
components. A full understanding of mechanisms sustaining biological diversity within and between communities needs such decomposition. Here, we propose an additive decomposition framework for estimating
α
,
β
and
γ
components of phylogenetic entropy. Based on simulated trees, we demonstrate its robustness to phylogenetic tree shape and species richness. Our decomposition fulfils the requirements of both independence between components and weak monotonicity. Finally, our decomposition can also be adapted to the partitioning of functional diversity across different scales with the same desirable properties.
Intraspecific queen parasitism in a highly eusocial bee
Authors: Wenseleers Tom , Alves Denise A. , Francoy Tiago M. , Billen Johan , Imperatriz-Fonseca Vera L.
Published: October 2010

Insect societies are well-known for their advanced cooperation, but their colonies are also vulnerable to reproductive parasitism. Here, we present a novel example of an intraspecific social parasitism in a highly eusocial bee, the stingless beeMelipona scutellaris. In particular, we provide genetic evidence which shows that, upon loss of the mother queen, many colonies are invaded by unrelated queens that fly in from unrelated hives nearby. The reasons for the occurrence of this surprising form of social parasitism may be linked to the fact that unlike honeybees,Meliponabees produce new queens in great excess of colony needs, and that this exerts much greater selection on queens to seek alternative reproductive options, such as by taking over other nests. Overall, our results are the first to demonstrate that queens in highly eusocial bees can found colonies not only via supersedure or swarming, but also by infiltrating and taking over other unrelated nests.
Parasitic infection reduces dispersal of ciliate host
Authors: Fellous Simon , Quillery Elsa , Duncan Alison B. , Kaltz Oliver
Published: October 2010

Parasitic infection can modify host mobility and consequently their dispersal capacity. We experimentally investigated this idea using the ciliateParamecium caudatumand its bacterial parasiteHolospora undulata. We compared the short-distance dispersal of infected and uninfected populations in interconnected microcosms. Infection reduced the proportion of hosts dispersing, with levels differing among host clones. Host populations with higher densities showed lower dispersal, possibly owing to social aggregation behaviour. Parasite isolates that depleted host populations most had the lowest impact on host dispersal. Parasite-induced modification of dispersal may have consequences for the spatial distribution of disease, host and parasite genetic population structure, and coevolution.
Applying the method of normal forms to second-order nonlinear vibration problems
Authors: Neild Simon A. , Wagg David J.
Published: October 2010

Vibration problems are naturally formulated with second-order equations of motion. When the vibration problem is nonlinear in nature, using normal form analysis currently requires that the second-order equations of motion be put into first-order form. In this paper, we demonstrate that normal form analysis can be carried out on the second-order equations of motion. In addition, for forced, damped, nonlinear vibration problems, we show that the invariance properties of the first- and second-order transforms differ. As a result, using the second-order approach leads to a simplified formulation for forced, damped, nonlinear vibration problems.
Gaussian curvature from flat elastica sheets
Authors: Modes C. D. , Bhattacharya K. , Warner M.
Published: October 2010

We discuss methods of reversibly inducing non-developable surfaces from flat sheets of material at the micro-scale all the way to macroscopic objects. We analyse the elastic ground states of a nematic glass in the membrane approximation as a function of temperature for disclination defects of topological charge +1. An aim is to show that by writing an appropriate director field into such a solid, one could create a surface with Gaussian curvature, dynamically switchable from flat sheets while avoiding stretch energy. In addition to the prospect of programmable structures, such surfaces offer actuation via stretch in thin systems since when illumination is subsequently removed, unavoidable stretches return.
Optimum structure to carry a uniform load between pinned supports: exact analytical solution
Authors: Tyas A. , Pichugin A. V. , Gilbert M.
Published: October 2010

Recent numerical evidence indicates that a parabolic funicular is not necessarily the optimal structural form to carry a uniform load between pinned supports. When the constituent material is capable of resisting equal limiting tensile and compressive stresses, a more efficient structure can be identified, comprising a central parabolic section and networks of truss bars emerging from the supports. In the current article, a precise geometry for this latter structure is identified, avoiding the inconsistencies that render the parabolic form non-optimal. Explicit analytical expressions for the geometry, stress and virtual-displacement fields within and above the structure are presented. Furthermore, a suitable displacement field below the structure is computed numerically and shown to satisfy the Michell–Hemp optimality criteria, hence formally establishing the global optimality of this new structural form.
Hybrid approach to analysis of β-sheet structures based on signal processing and statistical consideration
Authors: Vojisavljevic V. , Pirogova E. , Davidovic D. M. , Cosic I.
Published: October 2010

A number of biotechnology applications are based on protein design. For this design, the relationship between a protein’s primary structure and its conformation is of vital importance. A β-sheet is a common feature of a protein’s two-dimensional structure; therefore, elucidating the principles governing β-sheet structure and its stability is critical for understanding the protein-folding process. In the three-dimensional representation of protein molecules,
C

α

carbon coordinates (carbon atom immediately adjacent to the carboxylate group) have often been employed instead of the complete set of coordinates for the corresponding residues. Using the
C

α

carbon coordinates, we showed that particular amino acids are not randomly distributed within a β-sheet structure. On the basis of a new statistical approach for the analysis of a spatial distribution of amino acids in a protein, presented by their physico-chemical parameters, the electron–ion interaction potential (EIIP) and hydrophobicity, are described here. The relationship between amino acid positions inside the β-sheet and the EIIP and hydrophobicity parameters was established. The correlation between amino acid propensities related to the β-sheet was examined using multiple cross-spectra analysis. We also applied the continuous wavelet transform for the analysis of selected β-sheet structures using the EIIP and hydrophobicity parameters. The findings provide new insight into conformational propensities of amino acids for the adaption of β-sheet structures.
Azooxanthellate? Most Hawaiian black corals contain
Symbiodinium
Authors: Wagner Daniel , Pochon Xavier , Irwin Leslie , Toonen Robert J. , Gates Ruth D.
Published: October 2010

The ecological success of shallow-water reef-building corals (Hexacorallia: Scleractinia) is framed by their intimate endosymbiosis with photosynthetic dinoflagellates in the genus
Symbiodinium
(zooxanthellae). In contrast, the closely related black corals (Hexacorallia: Anthipatharia) are described as azooxanthellate (lacking
Symbiodinium
), a trait thought to reflect their preference for low-light environments that do not support photosynthesis. We examined 14 antipatharian species collected between 10 and 396 m from Hawai'i and Johnston Atoll for the presence of
Symbiodinium
using molecular typing and histology.
Symbiodinium
internal transcribed spacer-2 (ITS-2) region sequences were retrieved from 43 per cent of the antipatharian samples and 71 per cent of the examined species, and across the entire depth range. The ITS-2 sequences were identical or very similar to those commonly found in shallow-water scleractinian corals throughout the Pacific. Histological analyses revealed low densities of
Symbiodinium
cells inside antipatharian gastrodermal tissues (0–92 cells mm
−3
), suggesting that the
Symbiodinium
are endosymbiotic. These findings confirm that the capacity to engage in endosymbiosis with
Symbiodinium
is evolutionarily conserved across the cnidarian subclass Hexacorallia, and that antipatharians associate with
Symbiodinium
types found in shallow-water scleractinians. This study represents the deepest record for
Symbiodinium
to date, and suggests that some members of this dinoflagellate genus have extremely diverse habitat preferences and broad environmental ranges.
The shape of things to come: woodland herb niche contraction begins during recruitment in mesic forest microhabitat
Authors: Warren Robert J. , Bradford Mark A.
Published: October 2010

Natural abundance is shaped by the abiotic requirements and biotic interactions that shape a species' niche, yet these influences are rarely decoupled. Moreover, most plant mortality occurs during early life stages, making seed recruitment critical in structuring plant populations. We find that natural abundance of two woodland herbs,Hexastylis arifoliaandHepatica nobilis, peaks at intermediate resource levels, a pattern probably formed by concurrent abiotic and biotic interactions. To determine how this abundance patterning reflects intrinsic physiological optima and extrinsic biotic interactions, we translocate adults and seeds to novel locations across experimentally extended abiotic gradients. These experiments indicate that the plant distributions probably reflect biotic interactions as much as physiological requirements, and that adult abundance provides a poor indication of the underlying niche requirements. The positive response exhibited by adult transplants in the wettest conditions is offset by increased fungal attack on buried seeds consistent with peak natural abundance where soil moisture is intermediate. This contraction of niche space is best described by Connell's model—species are limited by physiological tolerances where resources are low and biotic interactions where resources are high.
A general rule for sensory cue summation: evidence from photographic, musical, phonetic and cross-modal stimuli
Authors: To M. P. S. , Baddeley R. J. , Troscianko T. , Tolhurst D. J.
Published: October 2010

The Euclidean and MAX metrics have been widely used to model cue summation psychophysically and computationally. Both rules happen to be special cases of a more general Minkowski summation rule

, where
m
= 2 and ∞, respectively. In vision research, Minkowski summation with power
m
= 3–4 has been shown to be a superior model of how subthreshold components sum to give an overall detection threshold. Recently, we have previously reported that Minkowski summation with power
m
= 2.84 accurately models summation of
supra
threshold visual cues in photographs. In four suprathreshold discrimination experiments, we confirm the previous findings with new visual stimuli and extend the applicability of this rule to cue combination in auditory stimuli (musical sequences and phonetic utterances, where
m
= 2.95 and 2.54, respectively) and cross-modal stimuli (
m
= 2.56). In all cases, Minkowski summation with power
m
= 2.5–3 outperforms the Euclidean and MAX operator models. We propose that this reflects the summation of neuronal responses that are not entirely independent but which show some correlation in their magnitudes. Our findings are consistent with electrophysiological research that demonstrates signal correlations (
r
= 0.1–0.2) between sensory neurons when these are presented with natural stimuli.
Salticid predation as one potential driving force of ant mimicry in jumping spiders
Authors: Huang Jin-Nan , Cheng Ren-Chung , Li Daiqin , Tso I-Min
Published: October 2010

Many spiders possess myrmecomorphy, and species of the jumping spider genusMyrmarachneexhibit nearly perfect ant mimicry. Most salticids are diurnal predators with unusually high visual acuity that prey on various arthropods, including conspecifics. In this study, we tested whether predation pressure from large jumping spiders is one possible driving force of perfect ant mimicry in jumping spiders. The results showed that small non-ant-mimicking jumping spiders were readily treated as prey by large ones (no matter whether heterospecific or conspecific) and suffered high attack and mortality rates. The size difference between small and large jumping spiders significantly affected the outcomes of predatory interactions between them: the smaller the juvenile jumping spiders, the higher the predation risk from large ones. The attack and mortality rates of ant-mimicking jumping spiders were significantly lower than those of non-ant-mimicking jumping spiders, indicating that a resemblance to ants could provide protection against salticid predation. However, results of multivariate behavioural analyses showed that the responses of large jumping spiders to ants and ant-mimicking salticids differed significantly. Results of this study indicate that predation pressure from large jumping spiders might be one selection force driving the evolution of nearly perfect myrmecomorphy in spiders and other arthropods.
Helper effects on pup lifetime fitness in the cooperatively breeding red wolf (
Canis rufus
)
Authors: Sparkman Amanda M. , Adams Jennifer , Beyer Arthur , Steury Todd D. , Waits Lisette , Murray Dennis L.
Published: October 2010

The evolutionary maintenance of cooperative breeding systems is thought to be a function of relative costs and benefits to breeders, helpers and juveniles. Beneficial effects of helpers on early-life survivorship and performance have been established in several species, but lifetime fitness benefits and/or costs of being helped remain unclear, particularly for long-lived species. We tested for effects of helpers on early- and late-life traits in a population of reintroduced red wolves (
Canis rufus
), while controlling for ecological variables such as home-range size and population density. We found that the presence of helpers in family groups was positively correlated with pup mass and survival at low population density, but negatively correlated with mass/size at high density, with no relation to survival. Interestingly, mass/size differences persisted into adulthood for both sexes. While the presence of helpers did not advance age at first reproduction for pups of either sex, females appeared to garner long-term fitness benefits from helpers through later age at last reproduction, longer reproductive lifespan and a greater number of lifetime reproductive events, which translated to higher lifetime reproductive success. In contrast, males with helpers exhibited diminished lifetime reproductive performance. Our findings suggest that while helper presence may have beneficial short-term effects in some ecological contexts, it may also incur long-term sex-dependent costs with critical ramifications for lifetime fitness.
Social complexity and linguistic diversity in the Austronesian and Bantu population expansions
Authors: Walker Robert S. , Hamilton Marcus J.
Published: October 2010

Reconstructing the rise and fall of social complexity in human societies through time is fundamental for understanding some of the most important transformations in human history. Phylogenetic methods based on language diversity provide a means to reconstruct pre-historic events and model the transition rates of cultural change through time. We model and compare the evolution of social complexity in Austronesian (n= 88) and Bantu (n= 89) societies, two of the world's largest language families with societies representing a wide spectrum of social complexity. Our results show that in both language families, social complexity tends to build and decline in an incremental fashion, while the Austronesian phylogeny provides evidence for additional severe demographic bottlenecks. We suggest that the greater linguistic diversity of the Austronesian language family than Bantu likely follows the different biogeographic structure of the two regions. Cultural evolution in both the Bantu and Austronesian cases was not a simple linear process, but more of a wave-like process closely tied to the demography of expanding populations and the spatial structure of the colonized regions.
Transcriptional regulation, occurrence and putative role of the Pht family of Streptococcus pneumoniae
Authors: Rioux Stéphane , Neyt Cécile , Di Paolo Emmanuel , Turpin Laurence , Charland Nathalie , Labbé Steve , Mortier Marie-Cécile , Mitchell Tim J. , Feron Christiane , Martin Denis , Poolman Jan T.
Published: October 2010

Restricted to the genusStreptococcus, the Pht protein family comprises four members: PhtA, PhtB, PhtD and PhtE. This family has the potential to provide a protein candidate for incorporation in pneumococcal vaccines. Based on sequence analysis and on RT-PCR experiments, we show here that thephtgenes are organized in tandem but that their expression, except that ofphtD, is monocistronic. PhtD, PhtE, PhtB and PhtA are present in 100, 97, 81 and 62 % of the strains, respectively, and, by analysing its sequence conservation across 107 pneumococcal strains, we showed that PhtD displays very little variability. To analyse the physiological function of these proteins, several mutants were constructed. The quadruple Pht-deficient mutant was not able to grow in a poor culture medium, but the addition of Zn2+or Mn2+restored its growth capacity. Moreover, thephtDmRNA expression level increased when the culture medium was depleted in zinc. Therefore, we suggest that these proteins are zinc and manganese scavengers, and are able to store these metals and to release them when the bacterium faces an ion-restricted environment. The data also showed that this protein family, and more particularly PhtD, is a promising candidate to be incorporated into pneumococcal vaccines.
Roles for the Yb body components Armitage and Yb in primary piRNA biogenesis in Drosophila
Authors: Saito Kuniaki , Ishizu Hirotsugu , Komai Miharu , Kotani Hazuki , Kawamura Yoshinori , Nishida Kazumichi M. , Siomi Haruhiko , Siomi Mikiko C.
Published: October 2010

PIWI-interacting RNAs (piRNAs) protect genome integrity from transposons. In Drosophila ovarian somas, primary piRNAs are produced and loaded onto Piwi. Here, we describe roles for the cytoplasmic Yb body components Armitage and Yb in somatic primary piRNA biogenesis. Armitage binds to Piwi and is required for localizing Piwi into Yb bodies. Without Armitage or Yb, Piwi is freed from the piRNAs and does not enter the nucleus. Thus, piRNA loading is required for Piwi nuclear entry. We propose that a functional Piwi–piRNA complex is formed and inspected in Yb bodies before its nuclear entry to exert transposon silencing.
Leaf Senescence Is Accompanied by an Early Disruption of the Microtubule Network in Arabidopsis
Authors: Keech Olivier , Pesquet Edouard , Gutierrez Laurent , Ahad Abdul , Bellini Catherine , Smith Steven M. , Gardeström Per
Published: October 2010

The dynamic assembly and disassembly of microtubules (MTs) is essential for cell function. Although leaf senescence is a well-documented process, the role of the MT cytoskeleton during senescence in plants remains unknown. Here, we show that both natural leaf senescence and senescence of individually darkened Arabidopsis (Arabidopsis thaliana) leaves are accompanied by early degradation of the MT network in epidermis and mesophyll cells, whereas guard cells, which do not senesce, retain their MT network. Similarly, entirely darkened plants, which do not senesce, retain their MT network. While genes encoding the tubulin subunits and the bundling/stabilizing MT-associated proteins (MAPs) MAP65 and MAP70-1 were repressed in both natural senescence and dark-induced senescence, we found strong induction of the gene encoding the MT-destabilizing protein MAP18. However, induction of MAP18 gene expression was also observed in leaves from entirely darkened plants, showing that its expression is not sufficient to induce MT disassembly and is more likely to be part of a Ca2+-dependent signaling mechanism. Similarly, genes encoding the MT-severing protein katanin p60 and two of the four putative regulatory katanin p80s were repressed in the dark, but their expression did not correlate with degradation of the MT network during leaf senescence. Taken together, these results highlight the earliness of the degradation of the cortical MT array during leaf senescence and lead us to propose a model in which suppression of tubulin and MAP genes together with induction of MAP18 play key roles in MT disassembly during senescence.
Miocene and Post‐Miocene Proboscidea from East Africa.
Authors: MacInnes D. G.
Published: October 2010

Deinotherium (Kaup). The occurrence of Deinoiherium in Pleistocene deposits in Africa is now well known. The material from Kanam appears to belong to the species Deinotherium bozasi (Arambourg), originally described from the Omo River deposits. The Kanam teeth are slightly smaller than those from Olduvai, and may possibly be a more primitive form. This, however, is inconclusive owing to the great range of variation in the size of Deinotherium teeth.

Pentalopkodon (Falconer). The material from Kanam which is assigned to this genus may equally be compared with Dibunodon arvernensis of Europe, and Pentalopkodon sivalensis of Asia. The Pleistocene fauna of Africa appears, in the light of present knowledge, to have affinities with that of Asia rather than that of Europe, and for this reason the material is here taken to represent a geographical race of the Indian form Pentalopkodon sivalensis.

Stegodon (Falconer and Cautley). A fragmentary skull of Stegodon was found near Lake Edward, in deposits apparently contemporary with those of Kaiso. This is the second occurrence of this genus in Africa, and the teeth appear to be more advanced than those of S. clifti from the Pliocene of India, whilst differing in various respects from those of the other Asiatic species. The material is referred to a new species 8. fuchsi, named after the discoverer.

Archidiskodon (Pohlig). In the British Museum collections the material referred to Elepkas planifrons shows many variations, which can be arranged in an ascending series from the primitive form which Matsumoto calls Leith‐Adamsia (B.M. No. 36695) to the more advanced form (No. 15351). In the latter the structure of the ridges is very similar to that which is found in the primitive forms of Elephas (Archidiskodon) meridionalis. The Kanam series of deposits has yielded the remains of a variety of A. planifrons which is not exactly reproduced in the Indian material, but which has distinct affinities to the more primitive part of the planifrons series. In the same deposit at Kanam, however, there occurs another representative of the Archidiskodon which appears to correspond to the primitive forms of A. meridionalis. Thus, if these forms do show an ascending series, the occurrence of two widely differing varieties in a single deposit suggests that the more primitive of the two may be a survival from earlier times, which perhaps represents an almost unchanged branch of the primitive stock.

Palœoloxodon (Matsumoto). An African race of Palœoloxodon antiquus was first described from the deposits of Olduvai, in Tanganyika, under the subspecific name P. a. recki (Dietrich). Its occurrence at Kanjira indicates that the deposits of this locality are of the same general age as those of the Olduvai series.
Outreach screening of drug users for cirrhosis with transient elastography
Authors: Moessner Belinda K. , Jørgensen Tina R. , Skamling Merete , Vyberg Mogens , Junker Peter , Pedersen Court , Christensen Peer B.
Published: October 2010

Aims  Transient elastography (TE) is a non‐invasive sensitive tool for diagnosing cirrhosis in hospital‐based cohorts. This study aimed to evaluate TE as a screening tool for cirrhosis among drug users.

Design  Cross‐sectional study.

Setting  All treatment centres in the county of Funen, Denmark.

Participants  Drug users attending treatment centres during the presence of the study team.

Measurements  Liver stiffness measurements (LSM) by transient elastography using the Fibroscan device; blood tests for viral hepatitis, HIV infection and hyaluronic acid (HA) levels; and routine liver tests. Individuals with LSM ≥ 8 kPa were referred to the hospital for treatment evaluation. Individuals with LSM ≥ 12 kPa were recommended a liver biopsy.

Findings  Among 175 drug users negative for hepatitis C, 13% had LSM = 8–11.9 kPa and 4% had LSM ≥ 12 kPa; elevated LSM was associated with a body mass index (BMI) > 30. Among 128 drug users with chronic hepatitis C, 19.5% had LSM = 8–11.9 kPa and 21.1% had LSM ≥ 12 kPa (P < 0.001). Repeat LSM at liver biopsy performed a median 3 months after screening showed a significant decrease (<12 kPa) among 30% (six of 20), and this was independent of alcohol consumption, BMI, age and gender. In 29 patients where liver biopsy was performed a LSM ≥ 16 kPa predicted cirrhosis with 88.9% sensitivity and 90% specificity.

Conclusions  Transient elastography is a feasible screening tool for cirrhosis among drug users. Transient elastography identifies severe liver fibrosis in a significant proportion of drug users with hepatitis C infections but management should not be based on a single elevated liver stiffness measurement.
The population impact of smoke‐free workplace and hospitality industry legislation on smoking behaviour. Findings from a national population survey
Authors: Nagelhout Gera E. , Willemsen Marc C. , de Vries Hein
Published: October 2010

Aims  To study the impact of implementing smoke‐free workplace and hospitality industry legislation on smoking behaviour.

Design, setting and participants  A cross‐sectional population survey from 2001 to 2008 (n ≈ 18 000 per year) was used to assess trends and seasonal patterns in smoking and quitting, and to examine whether changes could be observed after the workplace smoking ban in the Netherlands in 2004 and the hospitality industry ban in 2008.

Measurements  Outcome measures were smoking prevalence, quit attempts and successful quit attempts. Interactions with educational level (socio‐economic status) and bar visiting (exposure to the hospitality industry ban) were tested.

Findings  The workplace ban was followed by a decrease in smoking prevalence (OR = 0.91, P < 0.001), but the hospitality industry ban was not (OR = 0.96, P = 0.127). Both bans, especially the workplace ban, were followed by an increase in quit attempts and successful quit attempts: workplace ban, OR = 1.31, P < 0.001; OR = 1.49, P < 0.001; hospitality industry ban, OR = 1.13, P = 0.013; OR = 1.44, P < 0.001. The workplace ban had a larger effect on successful quitting among higher‐educated (OR = 0.35, P < 0.001) than on lower‐educated respondents (OR = 0.74, P = 0.052). The hospitality industry ban had a larger effect on quit attempts among frequent bar visitors (OR = 1.48, P = 0.003) than on non‐bar visitors (OR = 0.71, P = 0.014).

Conclusions  A workplace smoking ban in the Netherlands was followed by more changes in smoking and quitting than a hospitality industry ban. The hospitality industry ban only appeared to have an impact on quit attempts, and not on smoking prevalence.
Development of a core drug list towards improving prescribing education and reducing errors in the UK
Authors: Baker Emma , Pryce Roberts Adele , Wilde Kirsty , Walton Hannah , Suri Sati , Rull Gurvinder , Webb Andrew
Published: October 2010

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• 8.9% medication orders written by doctors contain prescribing errors, which are made by all grades of doctor from foundation year 1 to consultant.

• Recommendations to improve prescribing safety include continuing education from medical school to retirement, as well as improvement of NHS systems.

• Priority areas for education in prescribing with potential to have impact on prescribing errors have not previously been identified.

WHAT THIS STUDY ADDS

• This study has identified 100 drugs most commonly prescribed in primary and secondary care and shown that these drugs are those most frequently associated with prescribing errors.

• This core drug list has potential to direct prescribing training for both undergraduate and postgraduate prescribers as part of a national strategy to reduce prescribing errors.

AIM To develop a core list of 100 commonly prescribed drugs to support prescribing education.

METHODS A retrospective analysis of prescribing data from primary care in England (2006 and 2008) and from two London Teaching Hospitals (2007 and 2009) was performed. A survey of prescribing by foundation year 1 (FY1) doctors in 39 NHS Trusts across London was carried out.

RESULTS A core list of 100 commonly prescribed drugs comprising ≥0.1% prescriptions in primary and/or secondary care was developed in 2006/7. The core list remained stable over 2 years. FY1 doctors prescribed 65% drugs on the list at least monthly. Seventy‐six% of FY1 doctors did not regularly prescribe any drugs not on the core list. There was a strong correlation between prescribing frequency (prescriptions for each drug class expressed as percentage of all prescriptions written) and error rate described in the EQUIP study (errors made when prescribing each drug class expressed as a percentage of all errors made), n= 39, r= 0.861, P= 0.000.

CONCLUSIONS Our core drug list identifies drugs that are commonly used and associated with error and is stable over at least 2 years. This list can now be used to develop learning resources and training programmes to improve prescribing of drugs in regular use. Complementary skills required for prescribing less familiar drugs must be developed in parallel. Ongoing research is required to monitor the effect of new training initiatives on prescribing error and patient safety.
Amoxicillin/clavulanic acid‐warfarin drug interaction: a randomized controlled trial
Authors: Zhang Qian , Simoneau Guy , Verstuyft Celine , Drouet Ludovic , Bal dit Sollier Claire , Alvarez Jean‐Claude , Rizzo‐Padoin Nathalie , Bergmann Jean Francois , Becquemont Laurent , Mouly Stéphane
Published: October 2010

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Increased INR was previously observed in patients treated with warfarin and amoxicillin/clavulanic acid (amoxiclav) combination. To date, no prospective study has yet evaluated the effect of amoxiclav on INR in patients on warfarin therapy and consequently, there are no clear‐cut conclusions or clear recommendations for clinicians.

WHAT THIS PAPER ADDS

• We provided the first systematic prospective evaluation of the interaction between amoxiclav and warfarin and found that amoxiclav did not modify INR in patients treated with stable warfarin therapy in the absence of any infectious or inflammatory syndrome, suggesting that the previously observed INR increase in these patients may not be attributable to a drug–drug interaction.

AIMS To investigate whether an interaction exists between amoxicillin/clavulanic acid (amoxiclav) and warfarin in patients treated with stable oral anticoagulant therapy.

METHODS In a double‐blind, cross‐over, placebo‐controlled study, 12 patients on stable warfarin therapy, received a 7 day amoxiclav regimen or placebo.

RESULTS The mean maximum increase in INR observed was 0.22 ± 0.3 with amoxiclav vs. 0.24 ± 0.6 with placebo (P= 0.94). The day 7–day 1 factor II, R(–) and S(–) warfarin plasma concentrations were similar during the amoxiclav and placebo study periods (P= 0.81, P= 0.45, P= 0.75, respectively).

CONCLUSION Amoxiclav did not modify anticoagulation in patients treated with stable warfarin therapy and without infection.
Phosphodiesterase (PDE) inhibitors in the treatment of lower urinary tract dysfunction
Authors: Ückert Stefan , Oelke Matthias
Published: October 2010

Several disorders of the human upper and lower urinary tract, such as urinary stone disease, lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) and detrusor overactivity, can be therapeutically addressed by influencing the function of the smooth musculature of the ureter, prostate or urinary bladder, respectively. In order to ensure a drug effect without significant adverse events, a certain degree of tissue selectivity is mandatory. The treatment of said conditions aims to focus on orally available drugs acting via intracellular signalling pathways. Specifically, the cyclic nucleotide monophosphate cyclic GMP represents an important mediator in the control of the outflow region (bladder, urethra). The use of phosphodiesterase (PDE) inhibitors, such as sildenafil, tadalafil, vardenafil, avanafil or udenafil, known to restrain the degradation of the second messenger cyclic GMP, offers great opportunities in the treatment of lower urinary tract dysfunction. PDE inhibitors are regarded as efficacious, have a rapid onset of action and favourable effect‐to‐side‐effect ratio. The role of PDE5 inhibitors in the treatment of BPH/LUTS and the overactive bladder has already been addressed in randomized, double‐blind, placebo‐controlled trials, as well as preliminary open‐label studies enrolling either several hundreds or only 20 patients. The purpose of this review is to focus on the potential use and clinical significance of PDE inhibitors in the treatment of storage and voiding dysfunctions of the lower urinary tract. The strategy of modulating the activity of PDE isoenzymes might represent a novel approach in patients with lower urinary tract dysfunction (LUTD).
Review of negative and low‐grade cervical smears in women with invasive cervical cancer after the first 3 years of the national cervical screening programme in Slovenia
Authors: Repše‐Fokter A. , Pogačnik A. , Snoj V. , Primic‐Žakelj M. , Fležar M. S.
Published: October 2010

A. Repše‐Fokter, A. Pogačnik, V. Snoj, M. Primic‐Žakelj and M. S. Fležar  Review of negative and low‐grade cervical smears in women with invasive cervical cancer after the first 3 years of the national cervical screening programme in Slovenia

Objective:  The purpose of the study was to perform a national review of negative, low‐grade and inadequate smears reported during the latest screening period before cervical cancer diagnosis in 2006, after the first 3 years of the screening programme.

Methods:  Among 162 new cervical cancer cases there were 47 (29%) without previous cytology, 47 (29%) with one high‐grade smear prior to diagnosis and 68 (42.0%) with at least one previous negative, low‐grade, atypical or inadequate smear 1–40 months before diagnosis. Of the latter 68 cases, 37 patients with 59 smears (together with 118 control slides) were included in the review as 31 had smears reported at laboratories no longer operating. Findings were related to the last cytology report before diagnosis as well as to histological type and stage of the cancer.

Results:  In our study group, 19 (51%) of 37 patients had squamous cell carcinoma, 15 (41%) adenocarcinoma and 3 (8%) adenosquamous carcinoma, compared with 121 (75%), 26 (16%), 12 (7%), respectively, and 3 (2%) other types, for all carcinomas. Twenty‐one of 37 women also had high‐grade cytology prior to diagnosis of cancer. Women with previous cytology (with or without recent high‐grade smears) were more likely to have stage I cancers than those without cytology (P < 0.0001). The expert group upgraded 17/33 smears in the patients with squamous carcinomas, which was more than in those with adeno‐ and adenosquamous carcinomas (5/24, P < 0.05).

Conclusion:  As expected, a higher proportion of smears preceding adenocarcinomas were true negative. Under‐diagnosed smears were not related to cancer stage or last cytology report before diagnosis.
Single live‐bacterial cell assay of promoter activity and regulation
Authors: Teramoto Jun , Yamanishi Yoko , Magdy El‐Shimy H. , Hasegawa Akiko , Kori Ayako , Nakajima Masahiro , Arai Fumihito , Fukuda Toshio , Ishihama Akira
Published: October 2010

Laboratory cultures of a single species of bacteria harboring the same genetic background include heterogeneous cell populations, each differing in apparent morphology and physiology, as found in natural environments. To get insights into difference in the genome expression between individual cells, we constructed various types of the cell chip for monitoring the growth and fate of individual bacterial cells. Immobilization of portions of Escherichia coli culture within these cell chips was established after raising the local temperature in the presence of poly‐(N‐isopropylacrylamide) (PNIPAAm). The newly developed cell‐chip system allows the investigation of activity and regulation of green fluorescent protein (GFP)‐fused promoter in single live‐bacterial cells for prolonged time under controlled culture conditions. Using this single‐cell observation system, we succeeded, for the first time, the real‐time single‐cell assay of promoter activity of the E. coli gcl gene encoding glyoxylate carboligase as a model system, and the kinetics of gcl induction by an effector glyoxylate. Marked heterogeneity was found in the expression level of the gcl promoter. The heterogeneity in gcl promoter activity was, however, confirmed by Flow cytometry of suspension cultures. Our success provides an experimental system for the increased demand of single‐cell biology in bacterial studies.
In vitro alterations in dental enamel exposed to acidic medicines
Authors: Valinoti Ana Carolina , da Silva Pierro Viviane Santos , da Silva Eduardo Moreira , Maia Lucianne Cople
Published: October 2010

Objective

To evaluate the effect of acidic medicines (Klaricid®, Claritin®, and Dimetapp®) on surface enamel in vitro.

Methods

Enamel blocks (n = 104) were randomly distributed into two groups: G1 (pH‐cycling simulating physiological oral conditions) and G2 (erosive conditions). Each group was divided into four subgroups, three to be immersed in the medicines and the control in deionized water. Specimen surfaces were evaluated for roughness and hardness at baseline and again after the in vitro experimental phase, which included 30 min immersions in the medicines twice daily for 12 days. Scanning electron microscopy (SEM) was also performed after the in vitro experimental phase.

Results

All medicines produced a significant reduction in hardness in G1 after 12 days (P < 0.05). The three medicines promoted greater roughness after both pH‐regimens – G1 and G2 (P < 0.01), except for Claritin in G1. Scanning electron microscopy analysis showed erosive patterns in all subgroups. Dimetapp® showed the most erosion and Klaricid® the least, in both groups.

Conclusion

Dimetapp® (lowest pH and viscosity) and deionized water (control) showed the most pronounced erosive patterns. Klaricid® (highest pH and viscosity) presented an in vitro protective effect against acid attacks perhaps due to its mineral content and viscosity.
Long‐distance seed and pollen dispersal inferred from spatial genetic structure in the very low–density rainforest tree,Baillonella toxispermaPierre, in Central Africa
Authors: NDIADE‐BOUROBOU D. , HARDY O. J. , FAVREAU B. , MOUSSAVOU H. , NZENGUE E. , MIGNOT A. , BOUVET J.‐M.
Published: October 2010

We analysed the spatial distribution of genetic diversity to infer gene flow forBaillonella toxispermaPierre (Moabi), a threatened entomophilous pollinated and animal‐dispersed Central African tree, with typically low density (5–7 adults trees/km2). Fifteen nuclear and three universal chloroplast microsatellites markers were used to type 247 individuals localized in three contiguous areas with differing past logging intensity. These three areas were within a natural forest block of approximately 2886 km2in Gabon. Expected heterozygosity and chloroplast diversity were Henuc = 0.570 andHcp = 0.761, respectively.FISwas only significant in one area (FIS = 0.076,P < 0.01) and could be attributed to selfing. For nuclear loci, Bayesian clustering did not detect discrete gene pools within and between the three areas and global differentiation (FSTnuc = 0.007,P > 0.05) was not significant, suggesting that they are one population. At the level of the whole forest, both nuclear and chloroplast markers revealed a weak correlation between genetic relatedness and spatial distance between individuals: Spnuc = 0.003 and Spcp = 0.015, respectively. The extent of gene flow (σ) was partitioned into global gene flow (σg) from 6.6 to 9.9 km, seed dispersal (σs) from 4.0 to 6.3 km and pollen dispersal (σp) from 9.8 to 10.8 km. These uncommonly high dispersal distances indicate that low‐density canopy trees in African rainforests could be connected by extensive gene flow, although, given the current threats facing many seed disperser species in Central Africa, this may no longer be the case.
Monophyletic origin of multiple clonal lineages in an asexual fish (Poecilia formosa)
Authors: STÖCK MATTHIAS , LAMPERT KATHRIN P. , MÖLLER DIRK , SCHLUPP INGO , SCHARTL MANFRED
Published: October 2010

Despite the advantage of avoiding the costs of sexual reproduction, asexual vertebrates are very rare and often considered evolutionarily disadvantaged when compared to sexual species. Asexual species, however, may have advantages when colonizing (new) habitats or competing with sexual counterparts. They are also evolutionary older than expected, leaving the question whether asexual vertebrates are not only rare because of their ‘inferior’ mode of reproduction but also because of other reasons. A paradigmatic model system is the unisexual Amazon molly, Poecilia formosa, that arose by hybridization of the Atlantic molly, Poecilia mexicana, as the maternal ancestor, and the sailfin molly, Poecilia latipinna, as the paternal ancestor. Our extensive crossing experiments failed to resynthesize asexually reproducing (gynogenetic) hybrids confirming results of previous studies. However, by producing diploid eggs, female F1‐hybrids showed apparent preadaptation to gynogenesis. In a range‐wide analysis of mitochondrial sequences, we examined the origin of P. formosa. Our analyses point to very few or even a single origin(s) of its lineage, which is estimated to be approximately 120 000 years old. A monophyletic origin was supported from nuclear microsatellite data. Furthermore, a considerable degree of genetic variation, apparent by high levels of clonal microsatellite diversity, was found. Our molecular phylogenetic evidence and the failure to resynthesize the gynogenetic P. formosa together with the old age of the species indicate that some unisexual vertebrates might be rare not because they suffer the long‐term consequences of clonal reproduction but because they are only very rarely formed as a result of complex genetic preconditions necessary to produce viable and fertile clonal genomes and phenotypes (‘rare formation hypothesis’).
Production of Interleukin‐13 is Influenced by the Interleukin‐4 −34TT and −590TT Genotype in Patients with Aggressive Periodontitis
Authors: Gonzales J. R. , Gröger S. , Haley G. , Bödeker R.‐H. , Meyle J.
Published: October 2010

Aggressive periodontitis (AgP) is a specific form of periodontal disease, with rapid destruction of the tissues supporting the teeth in otherwise young healthy individuals. We recently showed a higher frequency of the interleukin‐4 (IL‐4) −34TT and −590TT genotype in AgP patients compared to controls (P < 0.05). Herein, we demonstrated that this specific IL‐4 genotype exerts its function by increasing expression of IL‐4 and STAT6, and producing higher concentrations of IL‐4 in activated CD4+ cells of patients with AgP. In the present study, we investigated the effects of the IL‐4‐specific genotype on IL‐13, IL‐2 and IFN‐γ expression and production in activated CD4+ cells of patients with AgP and healthy controls. Results revealed higher IFN‐γ and IL‐2 expression and significantly increased IL‐13 production in the cells of the patients who were homozygous for the −34T and −590T alleles in comparison with the patients who were homozygous for the −34C and −590C alleles (P < 0.05). Results of controls with the −34C and −590C alleles were similar to those of AgP with the same genotype. To our knowledge, the present study is the first to show an effect of the −34TT and −590TT genotype on IL‐13 production. There is an increased production of IL‐13 by the T cells of aggressive periodontitis patients with the IL‐4 genotype.
A calcipotriene/betamethasone dipropionate two‐compound scalp formulation in the treatment of scalp psoriasis in Hispanic/Latino and Black/African American patients: results of the randomized, 8‐week, double‐blind phase of a clinical trial
Authors: Tyring Stephen , Mendoza Natalia , Appell Melanie , Bibby Adrian , Foster Richard , Hamilton Tiffani , Lee Mark
Published: October 2010

The calcipotriene/betamethasone dipropionate two‐compound scalp formulation has been shown to be safe and effective in the treatment of scalp psoriasis over 8 weeks, but the patients studied were mainly White and non‐Hispanic. The aim of this study was to evaluate the efficacy and safety of the two‐compound scalp formulation in the treatment of scalp psoriasis in Hispanic/Latino and Black/African American patients. A total of 99 Hispanic/Latino and 78 Black/African American patients were randomized double‐blind in a 3 : 1 ratio to 8 weeks of once daily treatment of scalp psoriasis with either the two‐compound scalp formulation (n = 135) or its vehicle (n = 42). In the two‐compound group, 71.9% of patients had cleared or minimal disease at week 8 by the investigator’s global assessment compared to 40.5% in the vehicle group (odds ratio 3.30; 95% CI 1.62–6.72; P < 0.001). For the five secondary efficacy response criteria, three (total sign score, thickness of scalp psoriasis, patient’s global assessment) showed that two‐compound scalp formulation was statistically significantly more effective than its vehicle, and the other two (redness and scaliness of scalp psoriasis) approached statistical significance in favor of the two‐compound scalp formulation. There was no statistically significant difference (P = 1.00) between the percentage of patients with adverse reactions in the two‐compound group (7.0%) and the vehicle group (7.9%). The two‐compound scalp formulation is safe and effective in the treatment of scalp psoriasis over 8 weeks in Hispanic/Latino and Black/African American patients.