bluuebunny/crossref_metadata_2025 huggingface dataset:
Francis Hauksbee and his air pump
Authors: Brundtland Terje
Published: July 2012

Francis Hauksbee was active in London between 1699 and 1713. During those years he built scientific instruments, gave public lectures on natural philosophy and worked as a curator of experiments for the Royal Society. His most celebrated instrument is the double-barrelled air pump, which represents the ‘state of the art’ of eighteenth-century vacuum technology in Britain. Based on original texts and an examination of extant pumps of this design, this article offers a description of the air pump and an account of some of the experiments performed with it. In addition, notes on existing Hauksbee pumps to be found in modern museums and collections are provided.
Sharp bounds on enstrophy growth in the viscous Burgers equation
Authors: Pelinovsky Dmitry
Published: July 2012

We use the Cole–Hopf transformation and the Laplace method for the heat equation to justify the numerical results on enstrophy growth in the viscous Burgers equation on the unit circle. We show that the maximum enstrophy achieved in the time evolution is scaled as

, where

is the large initial enstrophy, whereas the time needed for reaching the maximal enstrophy is scaled as

. These bounds are sharp for initial conditions given by odd
C
3
functions that are convex on half-period.
The coevolution of toxin and antitoxin genes drives the dynamics of bacterial addiction complexes and intragenomic conflict
Authors: Rankin Daniel J. , Turner Leighton A. , Heinemann Jack A. , Brown Sam P.
Published: July 2012

Bacterial genomes commonly contain ‘addiction’ gene complexes that code for both a toxin and a corresponding antitoxin. As long as both genes are expressed, cells carrying the complex can remain healthy. However, loss of the complex (including segregational loss in daughter cells) can entail death of the cell. We develop a theoretical model to explore a number of evolutionary puzzles posed by toxin–antitoxin (TA) population biology. We first extend earlier results demonstrating that TA complexes can spread on plasmids, as an adaptation to plasmid competition in spatially structured environments, and highlight the role of kin selection. We then considered the emergence of TA complexes on plasmids from previously unlinked toxin and antitoxin genes. We find that one of these traits must offer at least initially a direct advantage in some but not all environments encountered by the evolving plasmid population. Finally, our study predicts non-transitive ‘rock-paper-scissors’ dynamics to be a feature of intragenomic conflict mediated by TA complexes. Intragenomic conflict could be sufficient to select deleterious genes on chromosomes and helps to explain the previously perplexing observation that many TA genes are found on bacterial chromosomes.
Kin selection, not group augmentation, predicts helping in an obligate cooperatively breeding bird
Authors: Browning L. E. , Patrick S. C. , Rollins L. A. , Griffith S. C. , Russell A. F.
Published: July 2012

Kin selection theory has been the central model for understanding the evolution of cooperative breeding, where non-breeders help bear the cost of rearing young. Recently, the dominance of this idea has been questioned; particularly in obligate cooperative breeders where breeding without help is uncommon and seldom successful. In such systems, the direct benefits gained through augmenting current group size have been hypothesized to provide a tractable alternative (or addition) to kin selection. However, clear empirical tests of the opposing predictions are lacking. Here, we provide convincing evidence to suggest that kin selection and not group augmentation accounts for decisions of whether, where and how often to help in an obligate cooperative breeder, the chestnut-crowned babbler (
Pomatostomus ruficeps
). We found no evidence that group members base helping decisions on the size of breeding units available in their social group, despite both correlational and experimental data showing substantial variation in the degree to which helpers affect productivity in units of different size. By contrast, 98 per cent of group members with kin present helped, 100 per cent directed their care towards the most related brood in the social group, and those rearing half/full-sibs helped approximately three times harder than those rearing less/non-related broods. We conclude that kin selection plays a central role in the maintenance of cooperative breeding in this species, despite the apparent importance of living in large groups.
Ground squirrel tail-flag displays alter both predatory strike and ambush site selection behaviours of rattlesnakes
Authors: Barbour Matthew A. , Clark Rulon W.
Published: July 2012

Many species approach, inspect and signal towards their predators. These behaviours are often interpreted as predator-deterrent signals—honest signals that indicate to a predator that continued hunting is likely to be futile. However, many of these putative predator-deterrent signals are given when no predator is present, and it remains unclear if and why such signals deter predators. We examined the effects of one such signal, the tail-flag display of California ground squirrels, which is frequently given both during and outside direct encounters with northern Pacific rattlesnakes. We video-recorded and quantified the ambush foraging responses of rattlesnakes to tail-flagging displays from ground squirrels. We found that tail-flagging deterred snakes from striking squirrels, most likely by advertising squirrel vigilance (i.e. readiness to dodge a snake strike). We also found that tail-flagging by adult squirrels increased the likelihood that snakes would leave their ambush site, apparently by elevating the vigilance of nearby squirrels which reduces the profitability of the ambush site. Our results provide some of the first empirical evidence of the mechanisms by which a prey display, although frequently given in the absence of a predator, may still deter predators during encounters.
Genetic change for earlier migration timing in a pink salmon population
Authors: Kovach Ryan P. , Gharrett Anthony J. , Tallmon David A.
Published: July 2012

To predict how climate change will influence populations, it is necessary to understand the mechanisms, particularly microevolution and phenotypic plasticity, that allow populations to persist in novel environmental conditions. Although evidence for climate-induced phenotypic change in populations is widespread, evidence documenting that these phenotypic changes are due to microevolution is exceedingly rare. In this study, we use 32 years of genetic data (17 complete generations) to determine whether there has been a genetic change towards earlier migration timing in a population of pink salmon that shows phenotypic change; average migration time occurs nearly two weeks earlier than it did 40 years ago. Experimental genetic data support the hypothesis that there has been directional selection for earlier migration timing, resulting in a substantial decrease in the late-migrating phenotype (from more than 30% to less than 10% of the total abundance). From 1983 to 2011, there was a significant decrease—over threefold—in the frequency of a genetic marker for late-migration timing, but there were minimal changes in allele frequencies at other neutral loci. These results demonstrate that there has been rapid microevolution for earlier migration timing in this population. Circadian rhythm genes, however, did not show any evidence for selective changes from 1993 to 2009.
How selection structures species abundance distributions
Authors: Magurran Anne E. , Henderson Peter A.
Published: July 2012

How do species divide resources to produce the characteristic species abundance distributions seen in nature? One way to resolve this problem is to examine how the biomass (or capacity) of the spatial guilds that combine to produce an abundance distribution is allocated among species. Here we argue that selection on body size varies across guilds occupying spatially distinct habitats. Using an exceptionally well-characterized estuarine fish community, we show that biomass is concentrated in large bodied species in guilds where habitat structure provides protection from predators, but not in those guilds associated with open habitats and where safety in numbers is a mechanism for reducing predation risk. We further demonstrate that while there is temporal turnover in the abundances and identities of species that comprise these guilds, guild rank order is conserved across our 30-year time series. These results demonstrate that ecological communities are not randomly assembled but can be decomposed into guilds where capacity is predictably allocated among species.
The Role of Return Home Welfare Interviews in Responding to the Needs of Young Runaways
Authors: Mitchell Fiona , Malloch Margaret , Burgess Cheryl
Published: July 2012

When children and young people run away from home or care it is most often indicative of problems in their lives. Reporting on the findings of a recent evaluation, this study considers the role, delivery and impact of ‘return home welfare interviews’ (RHWIs) in identifying children and young people in need. It concludes that RHWIs function as an effective screening mechanism and can be facilitative in creating multiple pathways for referral to appropriate services. It challenges assumptions about the unsuitability of the police in undertaking RHWIs and highlights the importance of context, training and appropriate resourcing to the success of police delivery.
Biofertilizers and/or some micronutrients role on wheat plants grown on newly reclaimed soil
Authors: Eleiwa Mona E. , Hamed Eman R. , Shehata Heba Sh.
Published: July 2012

Pot experiment was conducted to study the effect of biofertilizers (inoculation with different bacterial isolates), foliar spraying with some micronutrients (Mn, Zn, Fe and Mn+Zn+Fe) and their interaction on growth, physiological parameters and nutrients content of wheat plants grown on reclaimed soil. Pot experiment was conducted in the greenhouse of National Research center, The experimental design was split plot with four replicates. Four biofertilizer treatments (un‐inoculated, Bacillus polymyxa, Azotobacter chroococcum or Azosprillium barasilense) were used and randomly distributed in the main pots. The foliar treatments with micronutrients were randomly distributed in the sub plots. The growth parameters (plant height, leaf area, roots, shoots and whole plant dry weights and number of tillers & leaves per plant); some physiological parameters (soluble sugar %, protein %, polysaccharide %, chl. A+b μg cm−1 leaf per plant, carotenoids μg g−1, IAA mg kg−1 and psll mol DCPIP reduced per mg chl. per h) and nutrient contents (N, P, K, Mg, Mn, Zn and Cu) of wheat plants were significantly increased by inoculating wheat grains with different bacteria as compared with un‐inoculated plants (control). The highest values of all the mentioned parameters were obtained by using Azospirillum brasilense followed by Azotobacter chroococcum and Bacillus polymyxa in decreasing order. Foliar spraying treatments significantly increased the growth parameters, physiological parameters as well as nutrients content of wheat plants as compared with control. Highest values were obtained by using (Mn+Fe+Zn) treatment followed by Zn, Fe and Mn in decreasing order. Micronutrients in wheat plants differed as the foliar treatments were differed, so application of any micronutrient individually significantly increased its content and enhanced the content of other micronutrients in wheat. Interaction between the used biofertilizers and foliar spraying with micronutrients significantly affected all the studied parameters of wheat plants, the highest were obtained by inoculating wheat grains with Azospirillum brasilense and spraying the plants with (Mn+Fe+Zn) treatment, while the lowest values were attained by un‐inoculated grains (control) and spraying the wheat plants with tap water (control). Effective microorganisms in combination with micronutrients could be recommended to farmers to lead higher wheat yield.
Randomised clinical trial: alosetron improves quality of life and reduces restriction of daily activities in women with severe diarrhoea‐predominant IBS
Authors: Cremonini F. , Nicandro J. P. , Atkinson V. , Shringarpure R. , Chuang E. , Lembo A.
Published: July 2012

Background

Patients with irritable bowel syndrome with diarrhoea (IBS‐D) experience restriction in daily activities and decreased health‐related quality of life (QOL).

Aim

To investigate effects of alosetron on patient‐reported health‐related QOL, satisfaction and productivity in women with severe IBS‐D.

Methods

A total of 705 women (severe IBS‐D, Rome II criteria) randomised to alosetron 0.5 mg QD, 1 mg QD, 1 mg BID, or placebo for 12 weeks were studied. IBSQOL, treatment satisfaction, daily activities, and lost workplace productivity (LWP) were evaluated at randomisation and Week 12.

Results

One or more doses of alosetron significantly improved all IBSQOL domains except for sexual function from baseline vs. placebo. The magnitude of IBSQOL changes was consistent with a clinically meaningful effect. Alosetron 0.5 mg QD and 1 mg BID significantly reduced IBS interference with social/leisure activities and LWP from baseline vs. placebo [social/leisure (mean ±S.E.) days lost: −6.7 ± 0.8, −7.0 ± 0.9, P < 0.01; LWP (mean ± S.E.) h lost: −11.0 ± 3.3, −21.1 ± 4.1, P < 0.05 respectively]. Significantly more patients treated with alosetron reported satisfaction vs. placebo. Improvements in IBSQOL, LWP, and treatment satisfaction significantly correlated with global improvement of IBS symptoms. The incidence of adverse events with alosetron was low with constipation being the most commonly reported event. A single case of ischaemic colitis occurred, in a patient receiving alosetron 0.5 mg QD.

Conclusions

In women with severe IBS‐D, alosetron treatment, including 0.5 mg QD, resulted in statistically significant and clinically relevant improvements in health‐related QOL, restriction of daily activities and treatment satisfaction over placebo. IBS symptom improvement corresponded with positive changes in IBSQOL, LWP and treatment satisfaction.
Mathematical model of heterogeneous cancer growth with an autocrine signalling pathway
Authors: Hu G.‐M. , Lee C.‐Y. , Chen Y.‐Y. , Pang N.‐N. , Tzeng W. J.
Published: July 2012

Objectives

Cancer is a complex biological occurrence which is difficult to describe clearly and explain its growth development. As such, novel concepts, such as of heterogeneity and signalling pathways, grow exponentially and many mathematical models accommodating the latest knowledge have been proposed. Here, we present a simple mathematical model that exhibits many characteristics of experimental data, using prostate carcinoma cell spheroids under treatment.

Materials and methods

We have modelled cancer as a two‐subpopulation system, with one subpopulation representing a cancer stem cell state, and the other a normal cancer cell state. As a first approximation, these follow a logistical growth model with self and competing capacities, but they can transform into each other by using an autocrine signalling pathway.

Results and conclusion

By analysing regulation behaviour of each of the system parameters, we show that the model exhibits many characteristics of actual cancer growth curves. Features reproduced in this model include delayed phase of evolving cancer under 17AAG treatment, and bi‐stable behaviour under treatment by irradiation. In addition, our interpretation of the system parameters corresponds well with known facts involving 17AAG treatment. This model may thus provide insight into some of the mechanisms behind cancer.
Modeling the spatial and temporal heterogeneity of deforestation‐driven carbon emissions: the INPE‐EM framework applied to the Brazilian Amazon
Authors: Aguiar Ana Paula Dutra , Ometto Jean Pierre , Nobre Carlos , Lapola David Montenegro , Almeida Claudio , Vieira Ima Célia , Soares João Vianei , Alvala Regina , Saatchi Sassan , Valeriano Dalton , Castilla‐Rubio Juan Carlos
Published: July 2012

We present a generic spatially explicit modeling framework to estimate carbon emissions from deforestation (INPE‐EM). The framework incorporates the temporal dynamics related to the deforestation process and accounts for the biophysical and socioeconomic heterogeneity of the region under study. We build an emission model for the Brazilian Amazon combining annual maps of new clearings, four maps of biomass, and a set of alternative parameters based on the recent literature. The most important results are as follows: (a) Using different biomass maps leads to large differences in estimates of emission; for the entire region of the Brazilian Amazon in the last decade, emission estimates of primary forest deforestation range from 0.21 to 0.26 Pg C yr−1. (b) Secondary vegetation growth presents a small impact on emission balance because of the short duration of secondary vegetation. In average, the balance is only 5% smaller than the primary forest deforestation emissions. (c) Deforestation rates decreased significantly in the Brazilian Amazon in recent years, from 27 Mkm2 in 2004 to 7 Mkm2 in 2010. INPE‐EM process‐based estimates reflect this decrease even though the agricultural frontier is moving to areas of higher biomass. The decrease is slower than a non‐process instantaneous model would estimate as it considers residual emissions (slash, wood products, and secondary vegetation). The average balance, considering all biomass, decreases from 0.28 in 2004 to 0.15 Pg C yr−1 in 2009; the non‐process model estimates a decrease from 0.33 to 0.10 Pg C yr−1. We conclude that the INPE‐EM is a powerful tool for representing deforestation‐driven carbon emissions. Biomass estimates are still the largest source of uncertainty in the effective use of this type of model for informing mechanisms such as REDD+. The results also indicate that efforts to reduce emissions should focus not only on controlling primary forest deforestation but also on creating incentives for the restoration of secondary forests.
Improving plant functional groups for dynamic models of biodiversity: at the crossroads between functional and community ecology
Authors: Boulangeat Isabelle , Philippe Pauline , Abdulhak Sylvain , Douzet Roland , Garraud Luc , Lavergne Sébastien , Lavorel Sandra , Van Es Jérémie , Vittoz Pascal , Thuiller Wilfried
Published: July 2012

The pace of on‐going climate change calls for reliable plant biodiversity scenarios. Traditional dynamic vegetation models use plant functional types that are summarized to such an extent that they become meaningless for biodiversity scenarios. Hybrid dynamic vegetation models of intermediate complexity (hybrid‐DVMs) have recently been developed to address this issue. These models, at the crossroads between phenomenological and process‐based models, are able to involve an intermediate number of well‐chosen plant functional groups (PFGs). The challenge is to build meaningful PFGs that are representative of plant biodiversity, and consistent with the parameters and processes of hybrid‐DVMs. Here, we propose and test a framework based on few selected traits to define a limited number of PFGs, which are both representative of the diversity (functional and taxonomic) of the flora in the Ecrins National Park, and adapted to hybrid‐DVMs. This new classification scheme, together with recent advances in vegetation modeling, constitutes a step forward for mechanistic biodiversity modeling.
Sward structure management for a maximum short‐term intake rate in annual ryegrass
Authors: Amaral M. F. , Mezzalira J. C. , Bremm C. , Da Trindade J. K. , Gibb M. J. , Suñe R. W. M. , de F. Carvalho P. C.
Published: July 2012

This study tested the hypothesis that different sward structures, which were constructed by varying the pre‐ and post‐grazing sward heights of annual ryegrass pasture (Lolium multiflorumLam.) in southernBrazil, affect the short‐term intake rate (STIR) by dairy cows. Treatments consisted of four sward‐management strategies defined by a combination of two pre‐ (25 and 15 cm) and two post‐grazing sward heights (10 and 5 cm): 15‐05, 15‐10, 25‐05 and 25‐10. A completely randomized block design with four replicates was used for the experimental design. TheSTIRwas determined by the double‐weighing technique. Jaw movements were evaluated using automatic recorders (IGER BehaviourRecorder). The results showed that treatment 25‐10 allowed the animals to collect more herbage with a greater bite mass and thus resulted in a greaterSTIR. Treatments in which sward height was reduced to 10 cm generally favoured the ingestion process than treatments with a post‐grazing sward height of 5 cm.
Should pulp chamber pulpotomy be seen as a permanent treatment? Some preliminary thoughts
Authors: Simon S. , Perard M. , Zanini M. , Smith A. J. , Charpentier E. , Djole S. X. , Lumley P. J.
Published: July 2012

Aim

To investigate the benefits of pulpotomy (to the level of the floor of the pulp chamber) as an endodontic treatment for teeth with vital pulps.

Methodology

Seventeen patients, aged 7–54 years (mean of 37.2 year), were treated by pulpotomy and filling with ProRoot MTA® in premolar or molar teeth with vital pulps and without clinical evidence of irreversible pulpitis. The patients were then followed up for 12 to 24 months and the teeth then assessed by clinical and radiographic examination. Statistical analysis was performed with Kaplan–Meier survival probability statistics to estimate the survival of the treated teeth.

Results

At 24 months, the survival rate without any complementary treatment was estimated to be 82%. Two of the 17 treated teeth required root canal treatment for pain control and one for prosthetic reasons.

Conclusions

Under the conditions of this study, pulpotomy offered a viable alternative to root canal treatment for teeth with vital pulps in the short term. However, there is insufficient clinical evidence to consider this technique for the treatment of every permanent tooth. Nevertheless, it should be considered as a potential alternative approach to be further developed for future applications.
Characterization of a programmed necrosis process in 3‐dimensional cultures of dental pulp fibroblasts
Authors: Le Clerc J. , Pérard M. , Pellen‐Mussi P. , Novella A. , Tricot‐Doleux S. , Jeanne S. , Pérez F.
Published: July 2012

Aim

To analyse and compare the expression of nemosis markers in human lung and dental pulp fibroblasts and to determine whether this process differs by the type of mesenchymal cell.

Methods

Human dental pulp fibroblasts were obtained from unerupted third molars. Sound lung and pulpal fibroblasts were cultured in vitro as spheroids to determine the expression of the nemosis hallmark cyclooxygenase‐2 (COX‐2) mRNA using RT‐PCR and the concentrations of vascular endothelial growth factor (VEGF) and hepatocyte growth factor/scatter factor (HGF/SF) proteins using an ELISA test. Cell viability within spheroids was also compared with spheroid diameters over time.

Results

Increased expression of COX‐2 and VEGF was found in all spheroids compared with corresponding monolayers. Although HGF/SF was highly expressed in MRC5 cells, dental pulp fibroblasts aggregates maintained only a basal level compared with monolayer cultures. Further, the observed progressive loss of viable cells explained the decreased diameters of spheroids over time. The results demonstrate that nemosis occurs in sound lung and pulpal fibroblasts. This cell death also displays differences between these two different cell types, as they do not produce the same growth factors quantity release.

Conclusions

The nemosis process occurred in human dental pulp fibroblasts and is different between the two cell types studied. This in vitro experimental nemosis model could become an interesting inflammatory tool. More investigations are needed to compare nemosis process in dental pulp fibroblast and inflammation during pulpitis.
The usefulness of lean six sigma to the development of a clinical pathway for hip fractures
Authors: Niemeijer Gerard C. , Flikweert Elvira , Trip Albert , Does Ronald J. M. M. , Ahaus Kees T. B. , Boot Anja F. , Wendt Klaus W.
Published: July 2012

Aims and objectives

The objective of this study was to show the usefulness of lean six sigma (LSS) for the development of a multidisciplinary clinical pathway.

Methods

A single centre, both retrospective and prospective, non‐randomized controlled study design was used to identify the variables of a prolonged length of stay (LOS) for hip fractures in the elderly and to measure the effect of the process improvements – with the aim of improving efficiency of care and reducing the LOS.

Results

The project identified several variables influencing LOS, and interventions were designed to improve the process of care. Significant results were achieved by reducing both the average LOS by 4.2 days (−31%) and the average duration of surgery by 57 minutes (−36%). The average LOS of patients discharged to a nursing home reduced by 4.4 days.

Conclusion

The findings of this study show a successful application of LSS methodology within the development of a clinical pathway. Further research is needed to explore the effect of the use of LSS methodology at clinical outcome and quality of life.
The 2011 Program Evaluation Standards: a framework for quality in medical education programme evaluations
Authors: Ruhe Valerie , Boudreau J. Donald
Published: July 2012

Rationale, aims and objectives

Based on input from 400 stakeholders over 6 years, the 2011 Program Evaluation Standards represents an in‐depth analysis of values, meaning and measurement and their relationships in programme evaluation. Evaluation quality is achieved by balancing five attributes: utility, feasibility, propriety, accuracy and evaluation accountability. These attributes are used to organize 30 standards, 200 strategies and 197 hazards.

Method

In response to a call from the authors of the standards, we have used them to guide our meta‐evaluation of McGill's undergraduate physicianship programme.

Results

Our findings show how the standards illuminate the tensions, dilemmas and hazards inherent in all stages of programme evaluation studies and offer helpful strategies for designing and conducting high‐quality evaluation studies.

Conclusions

Based on our experience, the third edition needs to be used as a reference document in all stages of evaluations of medical education programmes.
Two CheW coupling proteins are essential in a chemosensory pathway of Borrelia burgdorferi
Authors: Zhang Kai , Liu Jun , Tu Youbin , Xu Hongbin , Charon Nyles W. , Li Chunhao
Published: July 2012

In the model organism Escherichia coli, the coupling protein CheW, which bridges the chemoreceptors and histidine kinase CheA, is essential for chemotaxis. Unlike the situation in E. coli, Borrelia burgdorferi, the causative agent of Lyme disease, has three cheW homologues (cheW1, cheW2 and cheW3). Here, a comprehensive approach is utilized to investigate the roles of the three cheWs in chemotaxis of B. burgdorferi. First, genetic studies indicated that both the cheW1 and cheW3 genes are essential for chemotaxis, as the mutants had altered swimming behaviours and were non‐chemotactic. Second, immunofluorescence and cryo‐electron tomography studies suggested that both CheW1 and CheW3 are involved in the assembly of chemoreceptor arrays at the cell poles. In contrast to cheW1 and cheW3, cheW2 is dispensable for chemotaxis and assembly of the chemoreceptor arrays. Finally, immunoprecipitation studies demonstrated that the three CheWs interact with different CheAs: CheW1 and CheW3 interact with CheA2 whereas CheW2 binds to CheA1. Collectively, our results indicate that CheW1 and CheW3 are incorporated into one chemosensory pathway that is essential for B. burgdorferi chemotaxis. Although many bacteria have more than one homologue of CheW, to our knowledge, this report provides the first experimental evidence that two CheW proteins coexist in one chemosensory pathway and that both are essential for chemotaxis.
Cationic antimicrobial peptides disrupt the Streptococcus pyogenes ExPortal
Authors: Vega Luis Alberto , Caparon Michael G.
Published: July 2012

Although they possess a well‐characterized ability to porate the bacterial membrane, emerging research suggests that cationic antimicrobial peptides (CAPs) can influence pathogen behaviour at levels that are sublethal. In this study, we investigated the interaction of polymyxin B and human neutrophil peptide (HNP‐1) with the human pathogen Streptococcus pyogenes. At sublethal concentrations, these CAPs preferentially targeted the ExPortal, a unique microdomain of the S. pyogenes membrane, specialized for protein secretion and processing. A consequence of this interaction was the disruption of ExPortal organization and a redistribution of ExPortal components into the peripheral membrane. Redistribution was associated with inhibition of secretion of certain toxins, including the SpeB cysteine protease and the streptolysin O (SLO) cytolysin, but not SIC, a protein that protects S. pyogenes from CAPs. These data suggest a novel function for CAPs in targeting the ExPortal and interfering with secretion of factors required for infection and survival. This mechanism may prove valuable for the design of new types of antimicrobial agents to combat the emergence of antibiotic‐resistant pathogens.
Mycobacterium tuberculosis WhiB4 regulates oxidative stress response to modulate survival and dissemination in vivo
Authors: Chawla Manbeena , Parikh Pankti , Saxena Alka , Munshi MohamedHusen , Mehta Mansi , Mai Deborah , Srivastava Anup K. , Narasimhulu K. V. , Redding Kevin E. , Vashi Nimi , Kumar Dhiraj , Steyn Adrie J. C. , Singh Amit
Published: July 2012

Host‐generated oxidative stress is considered one of the main mechanisms constraining Mycobacterium tuberculosis (Mtb) growth. The redox‐sensing mechanisms in Mtb are not completely understood. Here we show that WhiB4 responds to oxygen (O2) and nitric oxide (NO) via its 4Fe‐4S cluster and controls the oxidative stress response in Mtb. The WhiB4 mutant (MtbΔwhiB4) displayed an altered redox balance and a reduced membrane potential. Microarray analysis demonstrated that MtbΔwhiB4 overexpresses the antioxidant systems including alkyl hydroperoxidase (ahpC‐ahpD) and rubredoxins (rubA‐rubB). DNA binding assays showed that WhiB4 [4Fe‐4S] cluster is dispensable for DNA binding. However, oxidation of the apo‐WhiB4 Cys thiols induced disulphide‐linked oligomerization, DNA binding and transcriptional repression, whereas reduction reversed the effect. Furthermore, WhiB4 binds DNA with a preference for GC‐rich sequences. Expression analysis showed that oxidative stress repressed whiB4 and induced antioxidants in Mtb, while their hyper‐induction was observed in MtbΔwhiB4. MtbΔwhiB4 showed increased resistance to oxidative stress in vitro and enhanced survival inside the macrophages. Lastly, MtbΔwhiB4 displayed hypervirulence in the lungs of guinea pigs, but showed a defect in dissemination to their spleen. These findings suggest that WhiB4 systematically calibrates the activation of oxidative stress response in Mtb to maintain redox balance, and to modulate virulence.
Functional alteration in frontolimbic systems relevant to moral judgment in cocaine‐dependent subjects
Authors: Verdejo‐Garcia Antonio , Contreras‐Rodríguez Oren , Fonseca Francina , Cuenca Aida , Soriano‐Mas Carles , Rodriguez Joan , Pardo‐Lozano Ricardo , Blanco‐Hinojo Laura , de Sola Llopis Susana , Farré Magí , Torrens Marta , Pujol Jesús , de la Torre Rafael
Published: July 2012

Cocaine addiction is characterized by persistent decision‐making deficits, which are linked to structural and functional abnormalities in frontolimbic systems. Moral judgment is as a special instance of decision making, in which both cognitive and emotional signals must be adequately integrated to decide how to resolve moral dilemmas. Here, we employed a moral dilemmas functional magnetic resonance imaging (fMRI) task to explore possible alterations of frontolimbic systems in cocaine‐dependent subjects. We also explored if these alterations relate to more basic deficits in functional connectivity within these systems during spontaneous resting‐state activation. Ten cocaine‐dependent subjects and 14 non‐drug‐using controls participated in the study. Cocaine‐dependent subjects were carefully selected to discard potentially confounding co‐morbidities, and they underwent a uniform supervised abstinence period of 10 days. Both groups were scanned, and fMRI maps were generated to identify (1) brain response to moral dilemmas; and (2) the strength of functional connectivity within frontolimbic systems during resting‐state. During the moral dilemmas task, cocaine‐dependent subjects showed reduced activation involving frontolimbic structures as the anterior cingulate cortex (ACC), left insula and brain stem. Connectivity analyses showed that cocaine users had less resting‐state functional connectivity between ACC, thalamus, insula and brain stem. These results demonstrate that cocaine‐dependent subjects have functional alterations in the frontolimbic systems that support moral judgment and social decision making.
Potent rewarding and reinforcing effects of the synthetic cathinone 3,4‐methylenedioxypyrovalerone (MDPV)
Authors: Watterson Lucas R. , Kufahl Peter R. , Nemirovsky Natali E. , Sewalia Kaveish , Grabenauer Megan , Thomas Brian F. , Marusich Julie A. , Wegner Scott , Olive M. Foster
Published: July 2012

Reports of abuse and toxic effects of synthetic cathinones, frequently sold as ‘bath salts’ or ‘legal highs’, have increased dramatically in recent years. One of the most widely used synthetic cathinones is 3,4‐methylenedioxypyrovalerone (MDPV). The current study evaluated the abuse potential of MDPV by assessing its ability to support intravenous self‐administration and to lower thresholds for intracranial self‐stimulation (ICSS) in rats. In the first experiment, the rats were trained to intravenously self‐administer MDPV in daily 2‐hour sessions for 10 days at doses of 0.05, 0.1 or 0.2 mg/kg per infusion. The rats were then allowed to self‐administer MDPV under a progressive ratio (PR) schedule of reinforcement. Next, the rats self‐administered MDPV for an additional 10 days under short access (ShA; 2 hours/day) or long access (LgA; 6 hours/day) conditions to assess escalation of intake. A separate group of rats underwent the same procedures, with the exception of self‐administering methamphetamine (0.05 mg/kg per infusion) instead of MDPV. In the second experiment, the effects of MDPV on ICSS thresholds following acute administration (0.1, 0.5, 1 and 2 mg/kg, i.p.) were assessed. MDPV maintained self‐administration across all doses tested. A positive relationship between MDPV dose and breakpoints for reinforcement under PR conditions was observed. LgA conditions led to escalation of drug intake at 0.1 and 0.2 mg/kg doses, and rats self‐administering methamphetamine showed similar patterns of escalation. Finally, MDPV significantly lowered ICSS thresholds at all doses tested. Together, these findings indicate that MDPV has reinforcing properties and activates brain reward circuitry, suggesting a potential for abuse and addiction in humans.
Exploring older and younger adults' preferences for health information and participation in decision making using the Health Information Wants Questionnaire (HIWQ)
Authors: Xie Bo , Wang Mo , Feldman Robert , Zhou Le
Published: July 2012

Context

Existing measurements of patient preferences cover only a limited range of health information and participation in decision making. A broader approach is necessary to understand the breadth and variations in patient preferences.

Objective

To explore the breadth and variances in patient preferences for health information and participation in decision making and to understand the relationship between age and each type of preference.

Design

The Health Information Wants Questionnaire (HIWQ) was administered during May–December 2010 to gather data about the information and corresponding decision‐making autonomy participants would want in seven areas: diagnosis, treatment, laboratory tests, self‐care, complementary and alternative medicine (CAM), psychosocial factors and health‐care providers.

Setting

A large state university, public libraries and senior centres in Maryland, USA.

Participants

A convenience sample of 438 individuals, including 226 undergraduates (mean age = 20; SD = 2.15) and 212 community‐dwelling older adults (mean age = 72; SD = 9.00).

Main Outcome Measures

Ratings on the information and decision‐making items of the HIWQ.

Results

Participants expressed higher levels of preference for information than for participation in decision making on six of seven subscales. On the psychosocial subscale, they expressed stronger desire for participation in decision making than for information. Age had no predictive effect on the overall preferences or specific preferences for information and participation in decision making about standard treatments and CAM. The predictive effect of age on the other types of preferences varied significantly.

Conclusions

Physicians should take into account the breadth and variations in patient preferences. The predictive effect of age on patient preferences varied depending on the specific area of preferences.
When should we expect early bursts of trait evolution in comparative data? Predictions from an evolutionary food web model
Authors: Ingram T. , Harmon L. J. , Shurin J. B.
Published: July 2012

Conceptual models of adaptive radiation predict that competitive interactions among species will result in an early burst of speciation and trait evolution followed by a slowdown in diversification rates. Empirical studies often show early accumulation of lineages in phylogenetic trees, but usually fail to detect early bursts of phenotypic evolution. We use an evolutionary simulation model to assemble food webs through adaptive radiation, and examine patterns in the resulting phylogenetic trees and species’ traits (body size and trophic position). We find that when foraging trade‐offs result in food webs where all species occupy integer trophic levels, lineage diversity and trait disparity are concentrated early in the tree, consistent with the early burst model. In contrast, in food webs in which many omnivorous species feed at multiple trophic levels, high levels of turnover of species’ identities and traits tend to eliminate the early burst signal. These results suggest testable predictions about how the niche structure of ecological communities may be reflected by macroevolutionary patterns.
Anatomical Study of the Forearm and Hand Nerves of the Domestic Cat (Felis catus), Puma (Puma concolor) and Jaguar (Panthera onca)
Authors: Sánchez H. L. , Silva L. B. , Rafasquino M. E. , Mateo A. G. , Zuccolilli G. O. , Portiansky E. L. , Alonso C. R.
Published: July 2012

The innervation of the forearm and hand regions of cats has not been well described despite its importance for any surgery or any neurological disorder. It is probably the main area where disorders of peripheral nerves in this species are observed. In felines, the forelimbs facilitate the jump and represent the most important way for capturing prey. The main muscles and nerves involved in this activity are located in the region of the forearm and hand. The aim of the present study was to provide a detailed description of the innervation of the forearm and hand regions of the jaguar and puma, in comparison with that of the domestic cat, contributing thus with the anatomical knowledge of the area for applying it to surgery and pathology. The forearms of three pumas and two jaguars (all of them fixed in formalin) and of six domestic cats (fresh) were dissected. The nerves path and their forearm distribution patterns of all three species were described. The analysed results indicate that the observed variations between species are minimal; thus, the anatomy described for domestic cats can be widely applied to American wild felids.
Efficient selection against categorically scored hip dysplasia in dogs is possible using best linear unbiased prediction and optimum contribution selection: a simulation study
Authors: Malm S. , Sørensen A.C. , Fikse W.F. , Strandberg E.
Published: July 2012

Breeding to reduce the prevalence of categorically scored hip dysplasia (HD), based on phenotypic assessment of radiographic hip status, has had limited success. The aim of this study was to evaluate two selection strategies for improved hip status: truncation selection based on phenotypic record versus best linear unbiased prediction (BLUP), using stochastic simulation and selection scenarios resembling those in real dog populations. In addition, optimum contribution selection (OCS) was evaluated. Two traits were considered:HD(as a categorical trait with five classes and a heritability of 0.45 on the liability scale) and a continuous trait (with a heritability of 0.25) intended to represent other characteristics in the breeding goal. A population structure mimicking that in real dog populations was modelled. The categorical nature ofHDcaused a considerably lower genetic gain compared to simulatingHDas a continuous trait. Genetic gain was larger forBLUPselection than for phenotypic selection in all scenarios. However,BLUPselection resulted in higher rates of inbreeding. By applyingOCS, the rate of inbreeding was lowered to about the same level as phenotypic selection but with increased genetic improvement. For efficient selection againstHD, use ofBLUPbreeding values should be prioritized. In small populations,BLUPshould be used together withOCSor similar strategy to maintain genetic variation.
Reticular variant of mid‐dermal elastolysis
Authors: Posada Celia , No Nuria , De La Torre Carlos , Flórez Ángeles
Published: July 2012

Mid‐dermal elastolysis is a rare disorder characterised by focal loss of elastic tissue in the mid‐dermis. Most patients present with lesions of fine wrinkling (type I) or perifollicular papules (type II). The reticular variant (type III) has been described less often in the literature. We report a case of a young woman with type III mid‐dermal elastolysis.
Chromium levels in healthy and newly diagnosed type 1 diabetic children
Authors: Karagun Barbaros Sahin , Temiz Fatih , Ozer Guler , Yuksel Bilgin , Topaloglu Ali Kemal , Mungan Neslihan Onenli , Mazman Muhsin , Karagun Gokhan Murat
Published: July 2012

Background:  The aim of this study was to compare the chromium levels of plasma (PCL), erythrocyte (ECL) and urine (UCL) in type 1 diabetics and healthy subjects and to review the relation between metabolic parameters.

Methods:  We evaluated 165 subjects who were: newly diagnosed type 1 diabetics (group 1 [n= 29]); previously diagnosed type 1 diabetics (group 2 [n= 18]); non‐diabetic control subjects who were admitted and treated for any reason in hospital (group 3 [n= 21]); and two other groups of control subjects from two schools that have different socioeconomic levels (group 4 [n= 48] and group 5 [n= 49]).

Results:  PCL in group 1 and group 2 subjects (7.21 ± 4.78 and 10.94 ± 3.04 mcg/L, respectively) was significantly lower than in all control groups (21.84 ± 7.87, 16.11 ± 7.44, 17.25 ± 8.58 mcg/L, respectively) (P < 0.05). A significant difference in PCL between the group 1 and group 2 subjects was present (7.21 ± 4.78 and 10.94 ± 3.04, respectively) (P= 0.021). ECL (as tissue chromium) in group 1 and group 2 subjects (13.99 ± 11.37 and 19.64 ± 12.58, respectively) was significantly lower than in all control groups (28.20 ± 7.34.25, 49 ± 12.47, 26.37 ± 9.77 mcg/L, respectively) (P= 0.05). UCL in group 1 and group 2 subjects (11.44 ± 6.88 and 15.68 ± 6.75 mcg/L, respectively) was significantly lower than in group 3 subjects (28.83 ± 9.37mcg/L) (P < 0.05). There were significant correlations between length, bodyweight and PCL in the group 1 subjects (r = 0.42, P= 0.22 and r = 0.53, P= 0.03, respectively). There was a negative correlation between plasma glucose and UCL, which was not statistically significant in group 2 subjects (r =−0.4, P= 0.061).

Conclusion:  There was a negative chromium balance in type 1 diabetics. This negative balance may affect the insulin function badly. If this negative balance should be confirmed by recent studies we suggest that chromium supplementation with insulin is necessary for type 1 diabetes.
Sudden death in the first 2 years of life following immunization in the Republic of Korea
Authors: Choe Young June , Kim Jong‐Hee , Son Hyun Jin , Bae Geun‐Ryang , Lee Duk‐hyoung
Published: July 2012

Background:  Because the peak age for incidence of sudden deaths in infancy temporally coincides with the age of infant primary immunization, some have raised the question as to whether immunization is a risk factor for sudden death in infancy. Recent occurrence of two sudden deaths in infants in Korea has renewed concerns about the causal association between immunization and sudden deaths in infants.

Methods:  We carried out a retrospective review of data from the Korea Centers for Disease Control and Prevention Adverse Events Following Immunization Surveillance System and Vaccine Compensation programs.

Results:  From 1994 to 2011, a total of 45 cases of sudden deaths in the first 2 years of life following immunization were reported in Korea. The causes of death were classified as follows: infectious diseases (n= 13); accidental injuries (n= 7); congenital abnormalities (n= 2); and malignancy (n= 1). Of 20 sudden deaths in infancy, nine deaths met Brighton Collaboration case definition level I and II, and therefore were classified as possible sudden infant death syndrome cases. Hepatitis B vaccine (n= 13) was the most frequent vaccine with temporal association with sudden deaths in the first 2 years of life.

Conclusion:  Few sudden deaths in the first 2 years of life following immunization have been reported, despite the use of universal immunization in Korea. The majority of deaths in infancy did not meet case definition for sudden infant death syndrome. Encouraging investigators to perform thorough investigation, including postmortem autopsy and death scene examination, may promote data comparability and provide guidance on decision‐making in the vaccine‐safety monitoring and response system in Korea.
Preparing for aging among older villagers in northeastern Thailand
Authors: Rattanamongkolgul Duangduan , Sritanyarat Wanapa , Manderson Lenore
Published: July 2012

In the present study, we examined how older people prepared themselves in older age, by drawing on data from a qualitative study conducted in an urban area in Khon Kaen province, Thailand. Data were collected using observations, natural interviews, and in‐depth interviews with 35 older people, concurrently analyzed using thematic analysis. Preparation for aging, from their perspectives, consisted of attending to their physical health, spiritual well‐being, and preparing for death. The degree and quality of aging preparation was influenced by life events, personal health status, and family economic status. People actively prepare themselves for aging, and this appears to help them as they encounter life difficulties during their old age. Lifelong preparation strategies need to be studied further, so that locally‐appropriate strategies of health care can be implemented for older people.