bluuebunny/crossref_metadata_2025 huggingface dataset:
Betaproteobacteria Limnohabitans strains increase fecundity in the crustacean Daphnia magna: symbiotic relationship between major bacterioplankton and zooplankton in freshwater ecosystem
Authors: Peerakietkhajorn Saranya , Kato Yasuhiko , Kasalický Vojtěch , Matsuura Tomoaki , Watanabe Hajime
Published: May 2015

How symbioses between bacteria and aquatic animals influence food webs in freshwater ecosystems is a fundamental question in ecology. We investigated symbiosis between a crustacean zooplankton Daphnia magna and its dominant bacterial symbiont Limnohabitans, an abundant and globally distributed freshwater Betaproteobacteria. Aposymbiotic juvenile Daphnia were prepared and exposed to any of four Limnohabitans sp. – Limnohabitans strains DM1, 2KL‐3, 2KL‐7 and Limnohabitans planktonicus strain II‐D5, all previously found in D. magna digestive tract or culture. Re‐infected Daphnia were cultured until they produced the first clutch of juveniles. Limnohabitans strain DM1 and L. planktonicus strain II‐D5 successfully re‐infected Daphnia through single exposure at the first instar juvenile stage. In contrast to aposymbiotic Daphnia that produced non‐viable juveniles, re‐infected Daphnia produced viable juveniles and increased fecundity to levels of that of symbiotic Daphnia. Re‐infected Daphnia did not increase their number of eggs nor growth rates. Limnohabitans strains 2KL‐7 and 2KL‐3 could not recover fecundity even in multiple exposures during culture. This study shows the functional evidence demonstrating that a single bacterium Limnohabitans regulates fecundity of the consumer Daphnia through symbiosis. Our results indicated that symbiotic relationship between major bacterioplankton and zooplankton is important for maintaining the population of zooplankton in freshwater ecosystems.
Exerting Influence: The Common Agency Model
Authors: Mallard Graham
Published: May 2015

Since it was formalised in 1986, the use of the common agency model has generated important results in the fields of political influence, industrial organisation and public goods provision. A general version of the model is presented in this article, and its underlying intuition is explained, before a discussion of a topical application in each of the first two of these key fields. The article concludes with observations about the model's fruitfulness but also about its limitations and the avenues of research that remain to be examined.
Refinery Exchange Agreements: Pro‐Competitive, Anti‐Competitive or Benign?
Authors: Davey Alistair
Published: May 2015

This study examines the impact of the termination of refinery exchange agreements on retail petrol prices in Melbourne and Sydney in July 2002. This is done using autoregressive integrated moving average methodology coupled with intervention analysis using average weekly retail petrol price data. It is found the termination of refinery exchange agreements was associated with an increase in relative retail petrol prices. It is concluded that refinery exchange agreements were pro‐competitive, leading to relatively lower retail petrol prices for consumers arising from reduced transaction costs.
Rules and Flexibility in Public Budgeting: The Case of Budget Modernisation in Australia
Authors: Francesco Michael Di
Published: May 2015

This paper explores the features of public budgeting that make it resistant to efforts to balance central oversight and situational flexibility. Its aim is to help explain why systemic efforts at budget modernisation in the name of ‘devolution’ may have failed to deliver expanded budget flexibility. After defining flexibility, and briefly surveying how it can be inhibited by budget practices using the example of collaboration, the paper applies a taxonomy of general ‘budget rules’ to illustrate the trade‐offs between control and flexibility. It uses an analysis of budget reform in the Australian federal government over the last 30 years to identify a key set of ‘legacy reforms’ – all intended primarily to enable budget flexibility – to show how their design and redesign were purposed as modification to the general rules, and how, ultimately, they were constrained by them.
Association ofHLA‐B*27 with ankylosing spondylitis in Kurdish patients
Authors: Al‐Qadi Rawand , Salih Saadallah Fareeq , AlDoski Heleen Jalal , Nabeel Mariam , Ali Jumaa Hussein , Khasho Djwar , Yaqo Rafil Toma
Published: May 2015

Objective

To investigate the prevalence of human leukocyte antigen (HLA)‐B*27 among a healthy Kurdish population and in patients with ankylosing spondylitis.

Methods

The prevalence ofHLA‐B*27 was investigated in 209 healthy donors recruited from the Kurdistan Region of Iraq, and in 41 diagnosed ankylosing spondylitis patients. TheHLAstatuses for the patients and healthy donors were determined by using the low‐resolution OlerupSSP®HLAtyping kits.

Results

We observed that the prevalence ofHLA‐B*27 in healthy Kurdish donors was 3.8% (8/209). While the prevalence ofHLA‐B*27 in patients with ankylosing spondylitis was 65.9% (27/41 studied) with aP‐value of < 0.01. The relative risk of having the disease is 12 times higher in individuals withHLA‐B*27 compared to those who do not have it. The male‐to‐female ratio was 5.8 : 1 inHLA‐B*27 positive patients. The disease onset is earlier inHLA‐B*27‐positive patients.

Conclusion

From this study, we can conclude that the prevalence ofHLA‐B*27 among the Kurdish healthy population is 3.8% and there is a strong association betweenHLA‐B*27 and ankylosing spondylitis patients in the Kurdistan Region of Iraq.
IL23R gene polymorphism with juvenile idiopathic arthritis and its association with serum IL‐17A
Authors: Emami Samira , Ziaee Vahid , Rezaei Arezou , Sadr Maryam , Maddah Marzieh , Amirzargar Ali Akbar , Rezaei Nima
Published: May 2015

Aim

Interleukin 23 (IL‐23) and its receptor (IL‐23R) seem to play a major role in differentiation of CD4+ T cells into Th17 cells, induction of IL‐17 production, and activation of inflammatory pathways. Recent studies have suggested the association of IL‐23R polymorphisms with bone and articular inflammation in diseases such as ankylosing spondylitis and rheumatoid arthritis. The aim of this study was to determine the association between IL‐23R polymorphisms and juvenile idiopathic arthritis (JIA).

Method

A case–control study on 55 patients with JIA and 78 healthy controls was performed. All samples were genotyped for eight single nucleotide polymorphisms (SNPs) of IL23R (rs1004819, rs2201841, rs10889677, rs1495965, rs7517847, rs10489629, rs11209026 and rs1343151), using real‐time polymerase chain reaction Taqman genotyping technique. Forty‐two patients and 42 healthy controls were chosen randomly to measure the level of serum IL‐17A using enzyme‐linked immunosorbent assay.

Results

Although the heterozygous genotype of rs1004819 (GA) showed a weak, but statistically significant protective effect on polyarticular subtype (P = 0.03), none of the selected SNPs were associated with JIA overall. Indeed the analysis of haplotypes did not show any significant association with JIA. Serum IL‐17A level was not significantly different among patients and healthy controls and between JIA subtypes, as well. Moreover, there was no significant correlation between SNPs and serum IL‐17A concentration.

Conclusion

This is the first study of the IL‐23R gene in Iranian patients with JIA. Our results did not show any strong association between IL‐23R polymorphisms and JIA disease or serum IL‐17A levels. The only association was seen between rs1004819 and polyarticular JIA. Further larger studies may help clarify the role, if any, of the IL‐23/IL‐17 pathway in the pathogenesis of JIA.
Optimality and Contrasts in Block Designs with Unequal Treatment Replication
Authors: Williams Emlyn , Piepho Hans‐Peter
Published: May 2015

The computer construction of optimal or near‐optimal experimental designs is common in practice. Search procedures are often based on the non‐zero eigenvalues of the information matrix of the design. Minimising the average of the pairwise treatment variances can also be used as a search criterion. For equal treatment replication these approaches are equivalent to maximising the harmonic mean of the design's canonical efficiency factors, but differ when treatments are unequally replicated. This paper investigates the extent of these differences and discusses some apparent inconsistencies previously observed when comparing the optimality of equally and unequally replicated designs.
Mechanisms and clinical applications of chromosomal instability in lymphoid malignancy
Authors: Krem Maxwell M. , Press Oliver W. , Horwitz Marshall S. , Tidwell Timothy
Published: May 2015

Lymphocytes are unique among cells in that they undergo programmed DNA breaks and translocations, but that special property predisposes them to chromosomal instability (CIN), a cardinal feature of neoplastic lymphoid cells that manifests as whole chromosome‐ or translocation‐based aneuploidy. In several lymphoid malignancies translocations may be the defining or diagnostic markers of the diseases. CIN is a cornerstone of the mutational architecture supporting lymphoid neoplasia, though it is perhaps one of the least understood components of malignant transformation in terms of its molecular mechanisms. CIN is associated with prognosis and response to treatment, making it a key area for impacting treatment outcomes and predicting prognoses. Here we will review the types and mechanisms of CIN found in Hodgkin lymphoma, non‐Hodgkin lymphoma, multiple myeloma and the lymphoid leukaemias, with emphasis placed on pathogenic mutations affecting DNA recombination, replication and repair; telomere function; and mitotic regulation of spindle attachment, centrosome function, and chromosomal segregation. We will discuss the means by which chromosome‐level genetic aberrations may give rise to multiple pathogenic mutations required for carcinogenesis and conclude with a discussion of the clinical applications of CIN and aneuploidy to diagnosis, prognosis and therapy.
Abnormal corticosteroid signalling in airway smooth muscle: mechanisms and perspectives for the treatment of severe asthma
Authors: Chachi L. , Gavrila A. , Tliba O. , Amrani Y.
Published: May 2015

Growing in vivo evidence supports the concept that airway smooth muscle produces various immunomodulatory factors that could contribute to asthma pathogenesis via the regulation of airway inflammation, airway narrowing and remodelling. Targeting ASM using bronchial thermoplasty has provided undeniable clinical benefits for patients with uncontrolled severe asthma who are refractory to glucocorticoid therapy. The present review will explain why the failure of glucocorticoids to adequately manage patients with severe asthma could derive from their inability to affect the immunomodulatory potential of ASM. We will support the view that ASM sensitivity to glucocorticoid therapy can be blunted in severe asthma and will describe some of the factors and mechanisms that could be responsible for glucocorticoid insensitivity.
Epidermal consumption in benign and malignant melanocytic neoplasms
Authors: Bandino Justin P. , Kazlouskaya Viktoryia , Ergin Şeniz , Molés‐Poveda Paula , Cleaver Nathan J. , Kabigting Filamer D. , Shackelton Jeffrey B. , Thieu Khanh , Elston Dirk M.
Published: May 2015

Consumption of the epidermis associated with effacement of the rete ridge pattern has been cited as a useful criterion in the diagnosis of melanoma, but the significance of consumption in the absence of rete ridge effacement is unknown. We evaluated 701 melanocytic neoplasms for presence and ‘grade’ of consumption by melanocytic nests relative to diagnosis, body location, gender and age. We defined 1+ consumption as collections of melanocytes occupying greater than two thirds of the viable epidermis, with or without loss of the rete ridge pattern. Nests extending to the bottom of, within, and through the granular layer were graded 2+, 3+ and 4+, respectively. Consumption was more frequent and higher grades were found in melanomas followed by Spitz nevi compared with conventional melanocytic nevi (p < 0.001). Melanomas with higher Breslow thickness showed higher grades (p < 0.05). In conventional nevi, consumption occurred most frequently in back (13.7%), acral (11.9%) and scalp (9.8%) locations. Consumption without the requirement for rete ridge effacement occurs more frequently and at higher grades in melanoma. Higher grades correlate with higher Breslow thickness. Consumption is also common in Spitz nevi and occurs at lower grades in conventional (non‐Spitz) nevi, especially on the back, the scalp and at acral sites.
Relating mesocarnivore relative abundance to anthropogenic land‐use with a hierarchical spatial count model
Authors: Crimmins Shawn M. , Walleser Liza R. , Hertel Dan R. , McKann Patrick C. , Rohweder Jason J. , Thogmartin Wayne E.
Published: May 2015

There is growing need to develop models of spatial patterns in animal abundance, yet comparatively few examples of such models exist. This is especially true in situations where the abundance of one species may inhibit that of another, such as the intensively‐farmed landscape of the Prairie Pothole Region (PPR) of the central United States, where waterfowl production is largely constrained by mesocarnivore nest predation. We used a hierarchical Bayesian approach to relate the distribution of various land‐cover types to the relative abundances of four mesocarnivores in the PPR: coyoteCanis latrans, raccoonProcyon lotor, red foxVulpes vulpes, and striped skunkMephitis mephitis. We developed models for each species at multiple spatial resolutions (41.4 km2, 10.4 km2, and 2.6 km2) to address different ecological and management‐related questions. Model results for each species were similar irrespective of resolution. We found that the amount of row‐crop agriculture was nearly ubiquitous in our best models, exhibiting a positive relationship with relative abundance for each species. The amount of native grassland land‐cover was positively associated with coyote and raccoon relative abundance, but generally absent from models for red fox and skunk. Red fox and skunk were positively associated with each other, suggesting potential niche overlap. We found no evidence that coyote abundance limited that of other mesocarnivore species, as might be expected under a hypothesis of mesopredator release. The relationships between relative abundance and land‐cover types were similar across spatial resolutions. Our results indicated that mesocarnivores in the PPR are most likely to occur in portions of the landscape with large amounts of agricultural land‐cover. Further, our results indicated that track‐survey data can be used in a hierarchical framework to gain inferences regarding spatial patterns in animal relative abundance.
Landscape‐scale modelling of erosion processes and soil carbon dynamics under land‐use and climate change in agroecosystems
Authors: Lacoste M. , Viaud V. , Michot D. , Walter C.
Published: May 2015

Soil organic carbon (SOC) sequestration and soil redistribution are linked to soil properties, land use, farming system and climate. In a global‐change context, landscape and climate changes are expected and will most probably have impacts on changes in the soil. Soil change was simulated from 2010 to 2100 in an 86‐ha hedgerow landscape under different scenarios of landscape and climate changes. These scenarios combined contrasting land uses, hedgerow networks and climates. Two models were combined to evaluate the impact of these scenarios on soils: LandSoil, a soil redistribution model, and a SOC model based on RothC‐26.3. A soil thickness of 105 cm was considered. The results indicate that the main factor influencing soil degradation was land‐use change: when compared with the baseline business‐as‐usual landscape, the landscape with the most intensive agricultural systems had the greatest soil erosion (+0.26 t ha−1 year−1) and reduced mean SOC stocks (−17 t ha−1 after 90 years). The second significant factor was climate change, followed by hedgerow network density. Sensitivity to climate change differed between landscapes, and the most sensitive were those with continuous winter wheat. The results indicate that a hedgerow landscape is well adapted to protect soil (regarding carbon storage and soil erosion) in a context of climate change. However, this type of landscape is highly sensitive to cropping intensification and should be protected.
Improved estimates of organic carbon using proximally sensed vis–NIR spectra corrected by piecewise direct standardization
Authors: Ji W. , Viscarra Rossel R. A. , Shi Z.
Published: May 2015

We investigated the use of piecewise direct standardization (PDS) to remove the effects of water and other environmental factors from proximally sensed (field) visible–near infrared (vis–NIR) spectra. Our hypothesis was that the PDS‐standardized field spectra can be used to predict soil carbon effectively with calibrations derived from existing spectroscopic databases of spectra recorded in the laboratory on dried, ground and sieved samples. In our experiments we used field spectra recorded in situ with a portable spectrometer at 124 sites in 11 paddy fields in Zhejiang Province, China. We sampled the soil at these same sites, recorded their spectra in the laboratory and measured their soil organic carbon (SOC) contents with a conventional laboratory technique. Two‐thirds of the samples were used to relate the laboratory spectra to SOC by partial least squares regression (PLSR), and the remaining one‐third was used as an independent validation dataset. We selected a representative set of samples from corresponding field and laboratory spectra that we could use as the PDS transfer set. Piecewise direct standardization was used to relate each wavelength in the laboratory spectra to the corresponding wavelength and its neighbours in the field spectra. The field spectra of the validation samples were then corrected with PDS so that they acquired the characteristics of the spectra measured under laboratory conditions. The approach was evaluated by (i) quantifying the similarity between the PDS‐standardized spectra and their corresponding laboratory spectra, (ii) measuring the accuracy of their SOC predictions on the independent validation dataset and (iii) comparing these results with those of direct standardization (DS). Both PDS and DS led to considerable improvements in the predictions of SOC (R2 = 0.71, R2 = 0.60, respectively), compared with those with original field spectra (R2 = 0.03). However, fewer transfer samples were needed with PDS to obtain similar results.
Sebum, inflammasomes and the skin: current concepts and future perspective
Authors: Oyewole Anne O. , Birch‐Machin Mark A.
Published: May 2015

Increasing evidence has identified ultraviolet radiation (UVR) as the skins most potent mutagen as over exposure results in sunburn, inflammation and DNA damage, thus contributing to a photo‐ageing phenotype and possibly skin carcinogenesis. The lipid‐rich sebum secreted onto the surface of the skin plays an important physiological role in protecting the skin against external challenges. When skin is photosensitised by UVR, the lipid constituents of sebum are easily oxidised, generating several lipid photo‐oxidative products (e.g. squalene peroxides). These photo‐oxidative products have been shown to exert diverse toxicological, biological and immunological effects in the skin and have therefore been implicated in several detrimental skin alterations including premature skin ageing. The involvement of lipid peroxidation products in UVR‐induced inflammatory responses has been inadequately studied and highly controversial. Furthermore, it is unclear to what extent these oxidative products contribute to the underlying mechanisms of skin photo‐ageing. Therefore, this viewpoint essay will discuss the current knowledge on the effect of UVR exposure on skin surface lipids and how these may mediate UVR‐induced inflammatory responses which may be key contributors to photo‐damage in skin. This essay will also examine the potential role of inflammasomes (innate immune complexes) in the inflammatory response associated with UVR‐induced lipid peroxidation. Limited evidence is available on the interactions between sebaceous lipids, downstream mediators and concomitant immune response in sun‐exposed skin and clearer elucidation may lead to novel biomarkers of photo‐ageing and the incorporation of new molecules into current skin therapies which better target oxidised lipids and or downstream mediators/pathways.
Situated Transgressiveness: Exploring One Transwoman's Lived Experiences across Three Situated Contexts
Authors: Muhr Sara Louise , Sullivan Katie Rose , Rich Craig
Published: May 2015

This study investigates the lived experience of one transwoman, Claire, a public advocate and a manager with client services responsibilities. We examine Claire's story in order to discuss how situated contexts, such as different roles, locales and interactions, shape the way she experiences and perceives her trans body and gender identity. In particular, our analysis centres on how Claire's lived experience of personal and professional life shift across three different situated contexts, each enabling and constraining opportunities for political transgression. Our findings contribute to existing conversations within queer theory, transgender and organization studies by highlighting how situated contexts mediate the political potential of queer bodies at work. By developing the concept ‘situated transgressiveness’, this article challenges notions of transgender as a stable, ideal disruptive category and advances a more contextually sensitive approach to understanding the contingency of transgender lives and politics. Such insights are important in facilitating more nuanced understandings of the situatedness of transgression and transgender bodies within work and professional settings.
Discordant human epidermal growth factor receptor 2 overexpression in primary and metastatic upper gastrointestinal adenocarcinoma signifies poor prognosis
Authors: Hedner Charlotta , Tran Lena , Borg David , Nodin Björn , Jirström Karin , Eberhard Jakob
Published: May 2015

Aims

Targeted therapy with trastuzumab has proved to be effective for patients with gastric cancer overexpressing the human epidermal growth factor receptor 2 (HER2). Further studies are needed to determine the best method for assessment of HER2 overexpression. Moreover, the prognostic value of HER2 overexpression, including the significance of tumour heterogeneity, remains unclear.

Methods and results

HER2 overexpression and gene copy alterations were assessed by immunohistochemistry and silver in‐situ hybridization, respectively, on tissue microarrays with primary tumours and a subset of paired lymph node metastases from 174 patients with oesophageal or gastric adenocarcinoma. Cox proportional hazards modelling was applied to assess the prognostic impact of HER2 overexpression, intratumoural heterogeneity and conversion from primary tumour to metastasis. The correlation between protein expression and gene amplification was in line with previous studies. Primary–metastatic conversion was observed in 12.9% of the cases. HER2 overexpression or intratumoural heterogeneity was not prognostic, but primary–metastatic conversion was an independent predictor of a shorter overall survival (hazard ratio = 4.93).

Conclusions

As trastuzumab is emerging as an important targeted therapy for patients with upper gastointestinal cancer, these results underline the importance of further studies addressing the occurrence and clinical significance of discrepant HER2 expression in primary tumours and metastases.
Urban Growth as an Absorbing Markov Process
Authors: Stafford James
Published: May 2015

We propose to treat the growth of Alberta urban areas as an absorbing Markov chain. The transition matrix is derived from the experience of all urban areas in Canada from 1901 to 1951. The matrix is tested using Alberta urban areas from 1931 to 1971 and found to have a fairly good fit. A projection is made to urban areas in Alberta in 1981.
Northern Ireland 1968–1988: Enter an Art Historian in Search of a Useful Theory
Authors: Loftus Belinda
Published: May 2015

Publications and museum or art-gallery displays have tended to separate the visual images related to the Northern Ireland troubles into illustrations of history, works of art and media imagery. These distinct categories to some degree reflect the growing specialisation of art workers in Europe from the late eighteenth century onwards. But in the context of the Northern Ireland conflict visual images patently cut across such distinctions. Fine art works have direct political and therefore historical impact; media images use and are used by the producers of popular emblems; visual styles are held in common by all categories of imagery. The perpetuation of the separate history illustration/artwork/media picture categories when dealing with Northern Ireland imagery is therefore attributed to the formal and informal training of British and Irish historians and art historians. An alternative theoretical basis for examining the images related to the Northern Ireland conflict is suggested, in which those images are seen as parts of visual language codes, whose constant use and re-use simultaneously adds further layers of meaning to them, ensures their real impact on social, political, economic and religious developments, and modifies the overall visual language of their producers/users. This approach is related to the work of German and Austrian art-historians and their successors, American media studies focusing on the links between institutional organisation and visual style, anthropological analyses of ritual symbols and recent sociological use of linguistic theory.
Aesthetics and Digital Image Processing: Representational Craft in Contemporary Astronomy
Authors: Lynch Michael , Edgerton Samuel Y.
Published: May 2015

This paper examines whether ‘aesthetic’ considerations play a part in contemporary scientific work, and focuses on a scientific field undergoing rapid transformation through the introduction of digital imaging and image processing technologies. Interviews with astronomers at two image processing laboratories indicate that they orient explicitly to the ‘aesthetic’ judgments of their audiences when preparing images to promote and popularize their research. Although they acknowledge no such ‘aesthetic’ pretensions for their ‘scientific’ work, further analysis shows that a more ancient aesthetic, that of perfecting nature through a crafting of resemblances, is deeply a part of routine image processing work.
Pictures from the Subsoil, 1939
Authors: Bowker Geof
Published: May 2015

In this paper, an anatomy is given of the ambiguous representations of the subsoil produced by the Schlumberger Company during the 1930s. In ‘normal’ scientific work, ambiguities are carefully concealed so that the visual depictions that accompany a text lend it authority and give it the appearance of clarity. However, in a patent trial instigated by Schlumberger over electrical methods of picturing the subsoil adjacent to oil wells, sharp relief is thrown on the shading of information. In particular, we see that it was in the interests of Schlumberger and their rivals to produce graphics open to multiple interpretation, and that the juggling and control of these was a conscious part of their work – and indeed necessary to their survival.
The effect of subduction on the sulphur, carbon and redox budget of lithospheric mantle
Authors: Evans K.A. , Powell R.
Published: May 2015

Subduction of hydrated lithospheric mantle introduces HO, ferric iron, oxidized carbon and sulphur to the subduction zone system. The fate of these components is poorly known, but is intimately linked to the global geochemical cycles of iron, carbon and sulphur, the genesis of arc‐related ore deposits, the temporal evolution of mantle redox state and subduction‐related earthquakes and magmatism. thermocalc is used to provide first‐order constraints on the effect of subduction zone metamorphism on metamorphic redistribution of iron, carbon, sulphur and water in ultramafic rocks via construction of P−T and T‐X(O) pseudosections with open system calculation of the effect of fluid loss. The calculations replicate observed mineral assemblages in high‐P to low‐T ultramafic rocks at P−T conditions consistent with those suggested by other workers. The results are consistent with open system fluid loss without significant fluid infiltration. Water loss is complete by 850 C, the corresponding depth of fluid loss being consistent with that inferred for earthquakes in subducting slabs. Losses of carbon and sulphur are relatively minor, at around <5% and <1%, respectively, so it is envisaged that most carbon and sulphur subducted in ultramafic lithologies is transported to >5 GPa, below the depths of the source zone for arc volcanoes. Oxygen activity for rocks in closed systems that evolve with a fixed redox budget is calculated to change from ΔFMQ −1 at 350 C to over ΔFMQ +3 at 850 C. This result emphasizes the need to consider redox budget as well as oxygen activity when the results of experiments performed at fixed oxygen activity relative to some buffer are interpreted in the context of natural systems. In open systems, devolatilization is calculated to increase the redox budget and oxygen activity of the residue via loss of methane and HS at the brucite‐out and serpentine‐out reactions respectively. No fluid‐induced mechanism for oxidation of sub‐arc mantle by transfer of redox budget from hydrated ultramafic lithologies to the overlying sub‐arc mantle was identified, although further thermodynamic data on fluid species such as S are required to confirm this.
Assembly, trafficking and function of α1β2γ2 GABAA receptors are regulated by N‐terminal regions, in a subunit‐specific manner
Authors: Wong Lik‐Wei , Tae Han‐Shen , Cromer Brett A.
Published: May 2015

GABAA receptors are pentameric ligand‐gated ion channels that mediate inhibitory fast synaptic transmission in the central nervous system. Consistent with recent pentameric ligand‐gated ion channels structures, sequence analysis predicts an α‐helix near the N‐terminus of each GABAA receptor subunit. Preceding each α‐helix are 8–36 additional residues, which we term the N‐terminal extension. In homomeric GABAC receptors and nicotinic acetylcholine receptors, the N‐terminal α‐helix is functionally essential. Here, we determined the role of the N‐terminal extension and putative α‐helix in heteromeric α1β2γ2 GABAA receptors. This role was most prominent in the α1 subunit, with deletion of the N‐terminal extension or further deletion of the putative α‐helix both dramatically reduced the number of functional receptors at the cell surface. Conversely, deletion of the β2 or γ2 N‐terminal extension had little effect on the number of functional cell surface receptors. Additional deletion of the putative α‐helix in the β2 or γ2 subunits did, however, decrease both functional cell surface receptors and incorporation of the γ2 subunit into mature receptors. In the β2 subunit only, α‐helix deletions affected GABA sensitivity and desensitization. Our findings demonstrate that N‐terminal extensions and α‐helices make key subunit‐specific contributions to assembly, consistent with both regions being involved in inter‐subunit interactions.

image

N‐terminal α‐helices and preceding sequences of eukaryotic pentameric ligand‐gated ion channels are absent in prokaryotic homologues, suggesting they may not be functionally essential. Here, we show that in heteropentameric α1β2γ2 GABAA receptors, the role of these segments is highly subunit dependent. The extension preceding the α‐helix in the α subunit is crucial for assembly and trafficking, but is of little importance in β and γ subunits. Indeed, robust receptor levels remain when the extension and α‐helix are removed in β or γ subunits.
Phenolic compounds prevent the oligomerization of α‐synuclein and reduce synaptic toxicity
Authors: Takahashi Ryoichi , Ono Kenjiro , Takamura Yusaku , Mizuguchi Mineyuki , Ikeda Tokuhei , Nishijo Hisao , Yamada Masahito
Published: May 2015

Lewy bodies, mainly composed of α‐synuclein (αS), are pathological hallmarks of Parkinson's disease and dementia with Lewy bodies. Epidemiological studies showed that green tea consumption or habitual intake of phenolic compounds reduced Parkinson's disease risk. We previously reported that phenolic compounds inhibited αS fibrillation and destabilized preformed αS fibrils. Cumulative evidence suggests that low‐order αS oligomers are neurotoxic and critical species in the pathogenesis of α‐synucleinopathies. To develop disease modifying therapies for α‐synucleinopathies, we examined effects of phenolic compounds (myricetin (Myr), curcumin, rosmarinic acid (RA), nordihydroguaiaretic acid, and ferulic acid) on αS oligomerization. Using methods such as photo‐induced cross‐linking of unmodified proteins, circular dichroism spectroscopy, the electron microscope, and the atomic force microscope, we showed that Myr and RA inhibited αS oligomerization and secondary structure conversion. The nuclear magnetic resonance analysis revealed that Myr directly bound to the N‐terminal region of αS, whereas direct binding of RA to monomeric αS was not detected. Electrophysiological assays for long‐term potentiation in mouse hippocampal slices revealed that Myr and RA ameliorated αS synaptic toxicity by inhibition of αS oligomerization. These results suggest that Myr and RA prevent the αS aggregation process, reducing the neurotoxicity of αS oligomers.

image

To develop disease modifying therapies for α‐synucleinopathies, we examined effects of phenolic compounds on α‐synuclein (αS) oligomerization. Phenolic compounds, especially Myricetin (Myr) and Rosmarinic acid (RA), inhibited αS oligomerization and secondary structure conversion. Myr and RA ameliorated αS synaptic toxicity on the experiment of long‐term potentiation. Our results suggest that Myr and RA prevent αS aggregation process and reduce the neurotoxicity of αS oligomers. Phenolic compounds are good candidates of disease modifying drugs for α‐synucleinopathies.
‘Language of the past’ – Exploring past tense disruption during autobiographical narration in neurodegenerative disorders
Authors: Irish Muireann , Kamminga Jody , Addis Donna Rose , Crain Stephen , Thornton Rosalind , Hodges John R. , Piguet Olivier
Published: May 2015

Compromised retrieval of autobiographical memory (ABM) is well established in neurodegenerative disorders. The recounting of autobiographical events is inextricably linked to linguistic knowledge, yet no study to date has investigated whether tense use during autobiographical narration is disrupted in dementia syndromes. This study investigated the incidence of correct past tense use during ABM narration in patients with Alzheimer's disease (AD, n = 10) and semantic dementia (SD, n = 10) in comparison with healthy older Controls (n = 10). Autobiographical narratives were analysed for episodic content (internal/external) and classified according to tense use (past/present). Across both patient groups, use of the past tense was significantly compromised relative to Controls, with increased levels of off‐target present tense verbs observed. Voxel‐based morphometry analyses based on structural MRI revealed differential associations between past tense use and regions of grey matter intensity in the brain. Bilateral temporal cortices were implicated in the SD group, whereas frontal, lateral, and medial temporal regions including the right hippocampus emerged in AD. This preliminary study provides the first demonstration of the disruption of specific linguistic constructs during autobiographical narration in AD and SD. Future studies are warranted to clarify at what point in the disease trajectory such deficits in tense use emerge, and whether these deficits are a product or contributing factor in memory disruption in these syndromes.
Genetic rescue: a safe or risky bet?
Authors: Waller Donald M.
Published: May 2015

Small and isolated populations face threats from genetic drift and inbreeding. To rescue populations from these threats, conservation biologists can augment gene flow into small populations to increase variation and reduce inbreeding depression. Spectacular success stories include greater prairie chickens in Illinois (Westermeier et al. ), adders in Sweden (Madsen et al. ) and panthers in Florida (Johnson et al. ). However, we also know that performing such crosses risks introducing genes that may be poorly adapted to local conditions or genetic backgrounds. A classic example of such ‘outbreeding depression’ occurred when different subspecies of ibex from Turkey and the Sinai were introduced to assist recovery of an ibex population in Czechoslovakia (Templeton ). Despite being fertile, the hybrids birthed calves too early, causing the whole population to disappear. In the face of uncertainty, conservation biologists have tended to respect genetic identity, shying away from routinely crossing populations. In this issue of Molecular Ecology, Frankham () compiles empirical data from experimental studies to assess the costs and benefits of between‐population crosses (Fig. ). Crosses screened to exclude those involving highly divergent populations or distinct habitats show large heterosis with few apparent risks of outbreeding depression. This leads Frankham to advocate for using assisted gene flow more widely. But do the studies analysed in this meta‐analysis adequately test for latent outcrossing depression?
Limiting climatic factors and habitats of Erica tetralix at the eastern edge of its distribution range
Authors: Auniņa Liene , Auniņš Ainārs
Published: May 2015

We determined the limiting climatic factors, as well as the preferred habitats, of Erica tetralix L. at the eastern limit of its distribution range in the eastern Baltic region. It was found that E. tetralix in this region is a typical bog woodland plant preferring the wettest Sphagnum‐rich sites. Northern Atlantic wet heath fragments, base‐rich fens and species‐rich Nardus grasslands were other habitats for the species. The species composition in E. tetralix habitats resembled that found in appropriate habitats within its main distribution range, although the habitats in the eastern Baltic region lack many Atlantic floristic elements characteristic of wet heath.

A generalised linear model describing the climatic niche of E. tetralix in Latvia suggests that mild winters, which exhibit a combination of a shallow maximum depth of soil freezing and a large number of days when the air temperature exceeds 0°C, as well as abundant annual and winter precipitation, are the main factors allowing the presence of E. tetralix in Latvia. The climate parameters at the eastern limit of the species’ distribution range are consistent with those recorded as being suitable for E. tetralix elsewhere.

Our results reveal a strong relationship between oceanity and the distribution of E. tetralix. The climatic niche model suggests more climatically suitable areas in the Coastal Lowland geobotanical region where the species could potentially be found, most likely in bog woodlands. The future prospects to restore open areas of northern Atlantic wet heath with E. tetralix in Latvia are poor due to the decline in traditional land‐use; these areas have turned into bog woodlands or been converted into agricultural land.
Ultrasonography Leads to Accurate Diagnosis and Management of Painful Acromioclavicular Joint Cyst
Authors: Chang Chien George C. , Best Craig S. , Clay Brian S. , Candido Kenneth D.
Published: May 2015

Background

Acromioclavicular joint (ACJ) cysts are uncommon causes of shoulder pain. Type 1 ACJ cysts are limited to the ACJ and form in the presence of intact rotator cuff musculature, while type 2 cysts form secondary to biomechanical instability following rotator cuff tear or rupture.

Case Presentation

A 36‐year‐old overweight male with history of chronic left grade 2 (Rockwood classification) ACJ separation presented with intermittent pain at the distal superoanterior left clavicle. Physical examination revealed small step off at the ACJ and multiple subcutaneous cysts surrounding the ACJ. Ultrasound examination revealed a mild separation of the left ACJ, mild distension of the joint capsule, and a small, well‐circumscribed, compressible hypo‐echoic cyst overlying the clavicle. Palpation of the cyst against the clavicle reproduced the patient's symptoms of intermittent pain. He opted for ultrasound‐guided aspiration and subsequently had full resolution of his symptoms.

Discussion

Musculoskeletal ultrasound is useful for diagnosis and management of refractory musculoskeletal conditions that are commonly misdiagnosed on physical examination and translucent to radiographic imaging. Musculoskeletal ultrasound allowed us to exclude rotator cuff pathology, identify ACJ cyst as the pain generator, classify it as a type 1 ACJ cyst, and aid in needle guidance for successful aspiration leading to full resolution of our patient's pain.
Quantifying the dynamics of light tolerance inArabidopsisplants during ontogenesis
Authors: Carvalho Fabricio E. L. , Ware Maxwell A. , Ruban Alexander V.
Published: May 2015

The amount of light plants can tolerate during different phases of ontogenesis remains largely unknown. This was addressed here employing a novel methodology that uses the coefficient of photochemical quenching (qP) to assess the intactness of photosystemIIreaction centres. Fluorescence quenching coefficients, total chlorophyll content and concentration of anthocyanins were determined weekly during the juvenile, adult, reproductive and senescent phases of plant ontogenesis. This enabled quantification of the protective effectiveness of non‐photochemical fluorescence quenching (NPQ) and determination of light tolerance. The light intensity that caused photoinhibition in 50% of leaf population increased from ∼70 μmol m−2 s−1, for 1‐week‐old seedlings, to a maximum of 1385 μmol m−2 s−1for 8‐week‐old plants. After 8 weeks, the tolerated light intensity started to gradually decline, becoming only 332 μmol m−2 s−1for 13‐week‐old plants. The dependency of light tolerance on plant age was well‐related to the amplitude of protectiveNPQ(pNPQ) and the electron transport rates (ETRs). Light tolerance did not, however, show a similar trend to chlorophylla/bratios and content of anthocyanins. Our data suggest that pNPQis crucial in defining the capability of high light tolerance byArabidopsisplants during ontogenesis.
Inoculation with an enhanced N2‐fixing Bradyrhizobium japonicum strain (USDA110) does not alter soybean (Glycine max Merr.) response to elevated [CO2]
Authors: Sanz‐sáez Álvaro , Heath Katy D. , Burke Patricia V. , Ainsworth Elizabeth A.
Published: May 2015

This study tested the hypothesis that inoculation of soybean (Glycine max Merr.) with a Bradyrhizobium japonicum strain (USDA110) with greater N2 fixation rates would enhance soybean response to elevated [CO2]. In field experiments at the Soybean Free Air CO2 Enrichment facility, inoculation of soybean with USDA110 increased nodule occupancy from 5% in native soil to 54% in elevated [CO2] and 34% at ambient [CO2]. Despite this success, inoculation with USDA110 did not result in greater photosynthesis, growth or seed yield at ambient or elevated [CO2] in the field, presumably due to competition from native rhizobia. In a growth chamber experiment designed to study the effects of inoculation in the absence of competition, inoculation with USDA110 in sterilized soil resulted in nodule occupation of >90%, significantly greater 15N2 fixation, photosynthetic capacity, leaf N and total plant biomass compared with plants grown with native soil bacteria. However, there was no interaction of rhizobium fertilization with elevated [CO2]; inoculation with USDA110 was equally beneficial at ambient and elevated [CO2]. These results suggest that selected rhizobia could potentially stimulate soybean yield in soils with little or no history of prior soybean production, but that better quality rhizobia do not enhance soybean responses to elevated [CO2].
Congenital dacryocystoceles controlled by nCPAP via nasal mask in a neonate
Authors: Kuboi Toru , Okazaki Kaoru , Kusaka Takashi , Shimada Aki
Published: May 2015

Congenital dacryocystocele is a relatively rare type of nasolacrimal duct obstruction that may induce respiratory distress during the early neonatal period. We encountered a case of bilateral congenital dacryocystoceles with intranasal cysts in a premature infant delivered at 34 weeks of gestation. The patient developed symptoms of respiratory failure immediately after birth, but no ophthalmologic symptoms. Treatment with nasal continuous positive airway pressure via a nasal mask, instead of a nasal prong, effectively relieved the symptoms. Early diagnosis and appropriate treatment are critical for infants with nasal obstruction.
11p15 duplication and 13q34 deletion with Beckwith–Wiedemann syndrome and factor VII deficiency
Authors: Jurkiewicz Dorota , Kugaudo Monika , Tańska Anna , Wawrzkiewicz‐Witkowska Angelika , Tomaszewska Agnieszka , Kucharczyk Marzena , Cieślikowska Agata , Ciara Elżbieta , Krajewska‐Walasek Małgorzata
Published: May 2015

Here we report a patient with 11p15.4p15.5 duplication and 13q34 deletion presenting with Beckwith–Wiedemann syndrome (BWS) and moderate deficiency of factor VII (FVII). The duplication was initially diagnosed on methylation‐sensitive multiplex ligation‐dependent probe amplification. Array comparative genome hybridization confirmed its presence and indicated a 13q34 distal deletion. The patient's clinical symptoms, including developmental delay and facial dysmorphism, were typical of BWS with paternal 11p15 trisomy. Partial 13q monosomy in this patient is associated with moderate deficiency of FVII and may also overlap with a few symptoms of paternal 11p15 trisomy such as developmental delay and some facial features. To our knowledge this is the first report of 11p15.4p15.5 duplication associated with deletion of 13q34 and FVII deficiency. Moreover, this report emphasizes the importance of detailed clinical as well as molecular examinations in patients with BWS features and developmental delay.
Black tattoos protect against UVR‐induced skin cancer in mice
Authors: Lerche Catharina M. , Sepehri Mitra , Serup Jørgen , Poulsen Thomas , Wulf Hans Christian
Published: May 2015

Background

Black tattoos may involve risk of cancer owing to polycyclic aromatic hydrocarbons including benzo(a)pyrene (BaP) in inks. Ultraviolet radiation (UVR) induces skin cancer. The combination of UVR and black tattoo may therefore potentially be very problematic, but has not been previously studied.

Methods

Immunocompetent C3.Cg/TifBomTac mice (n = 99) were tattooed on the back with Starbrite Tribal Black™. This ink has a high content of the carcinogen BaP. Half of the mice were irradiated with three standard erythema doses UVR thrice weekly. Time to induction of first, second and third squamous cell carcinoma (SCC) was measured. Controls were ‘tattooed’ without ink.

Results

All irradiated mice developed SCCs while no malignant tumours were found in the nonirradiated group. In the tattooed and irradiated group, the development of the first, second and third SCC was significantly delayed in comparison with the irradiated controls without black tattoos (212, 232, 247 days vs. 163, 183, 191 days, P < 0.001).

Conclusion

In UVR‐irradiated black tattoos, remarkably, the development of UVR‐induced skin cancer was delayed by the tattoos. Skin reflectance measurement indicated that the protective effect of black pigment in the dermis might be attributed to UVR absorption by black pigment below the epidermis and thereby reduction of backscattered radiation.