bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic inactivation of the adenosine A2A receptor exacerbates brain damage in mice with experimental autoimmune encephalomyelitis
Authors: Yao Shu‐Qin , Li Zheng‐Zheng , Huang Qing‐Yuan , Li Fang , Wang Zhao‐Wei , Augusto Elisabete , He Jin‐Cai , Wang Xiao‐Tong , Chen Jiang‐Fan , Zheng Rong‐Yuan
Published: May 2012

Studies with multiple sclerosis patients and animal models of experimental autoimmune encephalomyelitis (EAE) implicate adenosine and adenosine receptors in modulation of neuroinflammation and brain injury. Although the involvement of the A1 receptor has been recently demonstrated, the role of the adenosine A2A receptor (A2AR) in development of EAE pathology is largely unknown. Using mice with genetic inactivation of the A2A receptor, we provide direct evidence that loss of the A2AR exacerbates EAE pathology in mice. Compared with wild‐type mice, A2AR knockout mice injected with myelin oligodendroglia glycoprotein peptide had a higher incidence of EAE and exhibited higher neurological deficit scores and greater decrease in body weight. A2AR knockout mice displayed increased inflammatory cell infiltration and enhanced microglial cell activation in cortex, brainstem, and spinal cord. In addition, demyelination and axonal damage in brainstem were exacerbated, levels of Th1 cytokines increased, and Th2 cytokines decreased. Collectively, these findings suggest that extracellular adenosine acting at A2ARs triggers an important neuroprotective mechanism. Thus, the A2A receptor is a potential target for therapeutic approaches to multiple sclerosis.
Constitutively active mutant gives novel insights into the mechanism of bitter taste receptor activation
Authors: Pydi Sai Prasad , Bhullar Rajinder Pal , Chelikani Prashen
Published: May 2012

J. Neurochem. (2012) 122, 537–544.

The human bitter taste receptors (T2Rs) belong to the G‐protein coupled receptor (GPCR) superfamily. T2Rs share little homology with the large subfamily of Class A G‐protein coupled receptors, and their mechanisms of activation are poorly understood. Guided by biochemical and molecular approaches, we identified two conserved amino acids Gly281.46 and Ser2857.47 present on transmembrane (TM) helices, TM1 and TM7, which might play important roles in T2R activation. Previously, it was shown that naturally occurring Gly511.46 mutations in the dim light receptor, rhodopsin, cause autosomal dominant retinitis pigmentosa, with the mutants severely defective in signal transduction. We mutated Gly281.46 and Ser2857.47 in T2R4 to G28A, G28L, S285A, S285T, and S285P, and carried out pharmacological characterization of the mutants. No major changes in signaling were observed upon mutation of Gly281.46 in T2R4. Interestingly, S285A mutant displayed agonist‐independent activity (approximately threefold over basal wild‐type T2R4 or S285T or S285P). We propose that Ser2857.47 stabilizes the inactive state of T2R4 by a network of hydrogen‐bonds connecting important residues on TM1‐TM2‐TM7. We compare and contrast this hydrogen‐bond network with that present in rhodopsin. Thus far, S285A is the first constitutively active T2R mutant reported, and gives novel insights into T2R activation.
Leucine‐rich repeat kinase 2 disturbs mitochondrial dynamics via Dynamin‐like protein
Authors: Niu Jingwen , Yu Mei , Wang Chunyan , Xu Zhiheng
Published: May 2012

J. Neurochem. (2012) 122, 650–658.

Mutations in Leucine‐rich repeat kinase 2 (LRRK2) are the leading causes of genetically inherited Parkinson’s disease (PD) identified so far. The underlying mechanism whereby missense alterations in LRRK2 initiate neurodegeneration remains largely unclear. Mitochondrial dysfunction has been recognized to contribute to the pathogenesis of both sporadic and familial PD. The pathogenic gain‐of‐function mutant form of LRRK2, LRRK2 G2019S, is associated with elevated kinase activity and PD. Here we show that LRRK2 G2019S can cause defects in the morphology and dynamics of mitochondria in cortical neurons. In neurons, endogenous LRRK2 and the mitochondrial fission factor Dynamin like protein 1 (DLP1) interact with and partially co‐localize with each other. DLP1 plays an essential role in LRRK2‐induced mitochondrial fission. In support of this, expression of LRRK2 leads to the translocation of DLP1 from the cytosol to the mitochondria and knockdown of DLP1 expression inhibits LRRK2‐induced mitochondrial fission. In addition, co‐expression of LRRK2 and DLP1 induces mitochondrial clearance. Furthermore, we have found that expression of LRRK2 leads to increased reactive oxygen species levels in cells. Taken together, our results provide insights into the pathobiology of LRRK2 and suggest that LRRK2 G2019S may induce neuronal dysfunction or cell death by disturbing normal mitochondrial fission/fusion dynamics and function.
Functional differences between ATP‐gated human and rat P2X3 receptors are caused by critical residues of the intracellular C‐terminal domain
Authors: Sundukova Mayya , Vilotti Sandra , Abbate Rita , Fabbretti Elsa , Nistri Andrea
Published: May 2012

J. Neurochem. (2012) 122, 557–567.

ATP‐activated P2X3 receptors of sensory ganglion neurons contribute to pain transduction and are involved in chronic pain signaling. Although highly homologous (97%) in rat and human species, it is unclear whether P2X3 receptors have identical function. Studying human and rat P2X3 receptors expressed in patch‐clamped human embryonic kidney (HEK) cells, we investigated the role of non‐conserved tyrosine residues in the C‐terminal domain (rat tyrosine‐393 and human tyrosine‐376) as key determinants of receptor function. In comparison with rat P2X3 receptors, human P2X3 receptors were more expressed and produced larger responses with slower desensitization and faster recovery. In general, desensitization was closely related to peak current amplitude for rat and human receptors. Downsizing human receptor expression to the same level of the rat one still yielded larger responses retaining slower desensitization and faster recovery. Mutating phenylalanine‐376 into tyrosine in the rat receptor did not change current amplitude; yet, it retarded desensitization onset, demonstrating how this residue was important to functionally link these two receptor states. Conversely, removing tyrosine from position 376 strongly down‐regulated human receptor function. The different topology of tyrosine residues in the C‐terminal domain has contrasting functional consequences and is sufficient to account for species‐specific properties of this pain‐transducing channel.
Subcellular localization of regulator of G protein signaling RGS7 complex in neurons and transfected cells
Authors: Liapis Evangelos , Sandiford Simone , Wang Qiang , Gaidosh Gabriel , Motti Dario , Levay Konstantin , Slepak Vladlen Z.
Published: May 2012

J. Neurochem. (2012) 122, 568–581.

The R7 family of regulators of G protein signaling (RGS) is involved in many functions of the nervous system. This family includes RGS6, RGS7, RGS9, and RGS11 gene products and is defined by the presence of the characteristic first found in Disheveled, Egl‐10, Pleckstrin (DEP), DEP helical extension (DHEX), Gγ‐like, and RGS domains. Herein, we examined the subcellular localization of RGS7, the most broadly expressed R7 member. Our immunofluorescence studies of retinal and dorsal root ganglion neurons showed that RGS7 concentrated at the plasma membrane of cell bodies, in structures resembling lamellipodia or filopodia along the processes, and at the dendritic tips. At the plasma membrane of dorsal root ganglia neurons, RGS7 co‐localized with its known binding partners R7 RGS binding protein (R7BP), Gαo, and Gαq. More than 50% of total RGS7‐specific immunofluorescence was present in the cytoplasm, primarily within numerous small puncta that did not co‐localize with R7BP. No specific RGS7 or R7BP immunoreactivity was detected in the nuclei. In transfected cell lines, ectopic RGS7 had both diffuse cytosolic and punctate localization patterns. RGS7 also localized in centrosomes. Structure‐function analysis showed that the punctate localization was mediated by the DEP/DHEX domains, and centrosomal localization was dependent on the DHEX domain.
Accuracy, completeness and comprehensiveness of information on pressure ulcers recorded in the patient record
Authors: Thoroddsen Asta , Sigurjónsdóttir Guðrún , Ehnfors Margareta , Ehrenberg Anna
Published: May 2012

Scand J Caring Sci; 2013; 27; 84–91

Accuracy, completeness and comprehensiveness of information on pressure ulcers recorded in the patient record

Aim:  To describe the accuracy, completeness and comprehensiveness of information on pressure ulcers documented in patient records.

Design and setting:  A cross‐sectional descriptive study performed in 29 wards at a university hospital in Iceland. The study included skin assessment of patients and retrospective audits of records of patients identified with pressure ulcers.

Participants:  A sample of 219 patients was inspected for signs of pressure ulcers on 1 day in 2008. Records of patients identified with pressure ulcers were audited (n = 45) retrospectively.

Results:  The prevalence of pressure ulcers was 21%. Information in patient records lacked accuracy, completeness and comprehensiveness. Only 60% of the identified pressure ulcers were documented in the patient records. The lack of accuracy was most prevalent for stage I pressure ulcers.

Conclusions:  The purpose of documentation to record, communicate and support the flow of information in the patient record was not met. The patient records lacked accuracy, completeness and comprehensiveness, which can jeopardise patient safety, continuity and quality of care. The information on pressure ulcers in patient records was found not to be a reliable source for the evaluation of quality in health care. To improve accuracy, completeness and comprehensiveness of data in the patient record, a systematic risk assessment for pressure ulcers and assessment and treatment of existing pressure ulcers based on evidence‐based guidelines need to be implemented and recorded in clinical practice. Health information technology, including the electronic health record with decision support, has shown promising results to facilitate and improve documentation of pressure ulcers.
Impacts of data quality on the setting of conservation planning targets using the species–area relationship
Authors: Metcalfe Kristian , Delavenne Juliette , Garcia Clément , Foveau Aurélie , Dauvin Jean‐Claude , Coggan Roger , Vaz Sandrine , Harrop Stuart R. , Smith Robert J.
Published: May 2012

Aim

The species–area relationship (SAR) is increasingly being used to set conservation targets for habitat types when designing protected area networks. This approach is transparent and scientifically defensible, but there has been little research on how it is affected by data quality and quantity.

Location

EnglishChannel.

Methods

We used a macrobenthic dataset containing 1314 sampling points and assigned each point to its associated habitat type. We then used theSAR‐based approach and tested whether this was influenced by changes in (i) the number of sampling points used to generate estimates of total species richness for each habitat type; (ii) the nonparametric estimator used to calculate species richness; and (iii) the level of habitat classification employed. We then compared our results with targets from a similar national‐level study that is currently being used to identifyMarineConservationZones in theUK.

Results

We found that targets were affected by all of the tested factors. Sample size had the greatest impact, with specific habitat targets increasing by up to 45% when sample size increased from 50 to 300. We also found that results based on theBootstrap estimator of species richness, which is the most widely used for setting targets, were more influenced by sample size than the other tested estimators. Finally, we found that targets were higher when using broader habitat classification levels or a larger study region. However, this could also be a sample size effect because these larger habitat areas generally contained more sampling points.

Main conclusions

Habitat targets based on theSARcan be strongly influenced by sample size, choice of richness estimator and the level of habitat classification. Whilst setting habitat targets using best‐available data should play a key role in conservation planning, further research is needed to develop methods that better account for sampling effort.
Global land use intensity and the endangerment status of mammal species
Authors: Pekin Burak K. , Pijanowski Bryan C.
Published: May 2012

Aim

Human land use activities are creating a biodiversity crisis. However, it is not clear how species respond to different intensities of land use at a global scale. We used spatial analyses to determine the relationships between human settlements, croplands, rangelands and forests of varying intensities and the endangerment status of mammal species across the globe. In doing so, we sought to assess the role of different land use and land management strategies in global biodiversity conservation.

Location

Global.

Methods

A GIS database with distribution ranges for 4734 Red‐Listed and non‐threatened terrestrial mammal species was obtained from the IUCN and combined with the global anthropogenic biomes dataset, which uses population density class (dense, residential, populated and remote) as a proxy for land use intensity. Ordered logistic regression was used to predict the effect of each land use intensity class on the probability of having a more endangered IUCN status for all mammal species together and for species within major mammal groups separately.

Results

The probability of having a more endangered status generally increased for mammal species as the proportion of urban settlements, mosaic and cropped ‘villages’, and residential and populated croplands within their distribution ranges increased. In contrast, endangerment probability of mammals decreased with proportion of irrigated, pastoral and rainfed ‘villages’, remote croplands and all rangeland classes. Endangerment probability also decreased with proportion of wildlands and remote forests, but increased with proportion of populated forests for several mammal groups.

Main conclusions

Urbanization and high‐intensity crop production pose a significant threat to mammals worldwide. In contrast, rangelands, low‐intensity croplands and certain low‐intensity human settlements may in fact help maintain mammal diversity at global scales. While the area of wild habitat available to species is also highly important for biodiversity conservation, forested lands that are disturbed or over utilized by humans do not benefit and may even endanger species.
Temporal analysis of vascular smooth muscle cell elasticity and adhesion reveals oscillation waveforms that differ with aging
Authors: Zhu Yi , Qiu Hongyu , Trzeciakowski Jerome P. , Sun Zhe , Li Zhaohui , Hong Zhongkui , Hill Michael A. , Hunter William C. , Vatner Dorothy E. , Vatner Stephen F. , Meininger Gerald A.
Published: May 2012

A spectral analysis approach was developed for detailed study of time‐resolved, dynamic changes in vascular smooth muscle cell (VSMC) elasticity and adhesion to identify differences in VSMC from young and aged monkeys. Atomic force microscopy (AFM) was used to measure Young’s modulus of elasticity and adhesion as assessed by fibronectin (FN) or anti‐beta 1 integrin interaction with the VSMC surface. Measurements demonstrated that VSMC cells from old vs. young monkeys had increased elasticity (21.6 kPa vs. 3.5 kPa or a 612% increase in elastic modulus) and adhesion (86 pN vs. 43 pN or a 200% increase in unbinding force). Spectral analysis identified three major frequency components in the temporal oscillation patterns for elasticity (ranging from 1.7 × 10−3 to 1.9 × 10−2 Hz in old and 8.4 × 10−4 to 1.5 × 10−2 Hz in young) and showed that the amplitude of oscillation was larger (P < 0.05) in old than in young at all frequencies. It was also observed that patterns of oscillation in the adhesion data were similar to the elasticity waveforms. Cell stiffness was reduced and the oscillations were inhibited by treatment with cytochalasin D, ML7 or blebbistatin indicating the involvement of actin–myosin‐driven processes. In conclusion, these data demonstrate the efficacy of time‐resolved analysis of AFM cell elasticity and adhesion measurements and that it provides a uniquely sensitive method to detect real‐time functional differences in biomechanical and adhesive properties of cells. The oscillatory behavior suggests that mechanisms governing elasticity and adhesion are coupled and affected differentially during aging, which may link these events to changes in vascular stiffness.
Changing countries, changing climates: achieving thermal comfort through adaptation in everyday activities
Authors: Fuller Sara , Bulkeley Harriet
Published: May 2012

Whilst increasing mobility leads to people regularly experiencing new climatic conditions, understanding how people actually adapt to new regimes of heat in their everyday lives is currently under researched. It is often assumed that increased demand for air conditioning will be an automatic response to heat, but widespread international variation in the current use of cooling technologies suggests a more complex situation. As one means of exploring how thermal comfort is achieved under different climatic conditions, this paper reports on the findings of a pilot study exploring adaptive practices in relation to heat with people who have recently migrated to Spain. The paper explores how thermal comfort is accomplished through adaptation in everyday activities including cooling technologies, clothing and routines and rhythms. The paper emphasises the importance of attending to how new routines emerge in the context of relocation and highlights a need for further research to understand how changing climatic conditions may serve to reconfigure the production of comfort.
Direct democracy and regional integration: Citizens' perceptions of treaty implications and the Irish reversal on Lisbon
Authors: GARRY JOHN
Published: May 2012

Analyses of voting in European Union referendums typically distinguish between ‘second‐order’ effects and the impact of substantive ‘issues’. In order to explain change in referendum outcome, two types of substantive issues are distinguished in this article. Focusing on Irish voting in the Lisbon Treaty referendums and using data from post‐referendum surveys, it is found that perceptions of treaty implications outperform underlying attitudes to EU integration in predicting vote choice at both referendums, and perceptions of treaty implications are strong predictors of vote change between the referendums. The findings have broadly positive implications for normative assessments of the usefulness of direct democracy as a tool for legitimising regional integration advance.
A Sumatriptan Iontophoretic Transdermal System for the Acute Treatment of Migraine
Authors: Goldstein Jerome , Smith Timothy R. , Pugach Neil , Griesser Jim , Sebree Terri , Pierce Mark
Published: May 2012

Objective.— Gastrointestinal symptoms, such as nausea and vomiting, occur almost universally at one time or another in patients during a migraine attack. One third of patients who experience migraine‐related nausea report that this symptom interferes with their ability to take oral medications. The sumatriptan iontophoretic transdermal system (NuPathe Inc., Conshohocken, PA, USA) uses proprietary technology to circumvent the gastrointestinal tract while delivering triptan therapy. This phase III randomized, double‐blind, placebo‐controlled trial evaluated the efficacy and tolerability of this system for the acute treatment of migraine.

Methods.— Patients were randomized to treat a single moderate‐to‐severe migraine attack with the sumatriptan iontophoretic transdermal system or placebo. The primary end point was the proportion of patients who were headache pain‐free 2 hours after patch activation. Other end points included the proportions of patients who reported headache pain relief, and freedom from nausea, photophobia, and phonophobia; rescue medication use; and tolerability.

Results.— Four hundred sixty‐nine patients were treated. Significantly more patients treated with the sumatriptan iontophoretic transdermal system compared with placebo experienced freedom from headache pain, nausea, photophobia, and phonophobia 2 hours after patch activation, experienced rapid and sustained headache pain relief, and used less rescue medication. Treatment‐emergent adverse events were reported by 50% and 44% of patients treated with the sumatriptan iontophoretic transdermal system and placebo, respectively. Most events were transient mild‐to‐moderate application‐site reactions.

Conclusions.— The sumatriptan iontophoretic transdermal system is effective and well tolerated, and may be particularly useful in patients with migraine‐related gastrointestinal symptoms such as nausea.
Efficacy of Transcranial Direct Current Stimulation and Repetitive Transcranial Magnetic Stimulation for Treating Fibromyalgia Syndrome: A Systematic Review
Authors: Marlow Nicole M. , Bonilha Heather S. , Short E. Baron
Published: May 2012

Objective:  To systematically review the literature to date applying repetitive transcranial magnetic stimulation (rTMS) or transcranial direct current stimulation (tDCS) for patients with fibromyalgia syndrome (FMS).

Method:  Electronic bibliography databases screened included PubMed, Ovid MEDLINE, PsychINFO, CINAHL, and Cochrane Library. The keyword “fibromyalgia” was combined with (“transcranial” and “stimulation”) or “TMS” or “tDCS” or “transcranial magnetic stimulation” or “transcranial direct current stimulation”.

Results:  Nine of 23 studies were included; brain stimulation sites comprised either the primary motor cortex (M1) or the dorsolateral prefrontal cortex (DLPFC). Five studies used rTMS (high‐frequency‐M1: 2, low‐frequency‐DLPFC: 2, high‐frequency‐DLPFC: 1), while 4 applied tDCS (anodal‐M1: 1, anodal‐M1/DLPFC: 3). Eight were double‐blinded, randomized controlled trials. Most (80%) rTMS studies that measured pain reported significant decreases, while all (100%) tDCS studies with pain measures reported significant decreases. Greater longevity of significant pain reductions was observed for excitatory M1 rTMS/tDCS.

Conclusion:  Studies involving excitatory rTMS/tDCS at M1 showed analogous pain reductions as well as considerably fewer side effects compared to FDA apaproved FMS pharmaceuticals. The most commonly reported side effects were mild, including transient headaches and scalp discomforts at the stimulation site. Yearly use of rTMS/tDCS regimens appears costly ($11,740 to 14,507/year); however, analyses to apapropriately weigh these costs against clinical and quality of life benefits for patients with FMS are lacking. Consequently, rTMS/tDCS should be considered when treating patients with FMS, particularly those who are unable to find adequate symptom relief with other therapies. Further work into optimal stimulation parameters and standardized outcome measures is needed to clarify associated efficacy and effectiveness.
Spinal Mechanisms of Pain and Analgesia
Authors: Miljanich George , Rauck Richard , Saulino Michael
Published: May 2012

Abstract:  Chronic pain—especially that which is refractory to conventional treatment—presents particular challenges to physicians and patients. Examination of the molecular and cellular mechanisms involved in this pathophysiology suggests that spinal instillation of therapeutic agents may offer an effective treatment option through the modification of the processing and sensation of chronic pain. Intrathecal therapy, used alone or in combination with other analgesic agents, may reduce chronic pain by attenuating both pre‐ and postsynaptic activities. This article reviews chronic pain pathophysiology and the mechanisms whereby spinally administered analgesics may modify chronic pain. Available treatment options are also considered, including recommendations from the 2007 Polyanalgesic Consensus Conference (PACC) guidelines on the use of intrathecal agents for nociceptive, neuropathic, and mixed pain.
Optimal Design for the Precise Estimation of an Interaction Threshold: The Impact of Exposure to a Mixture of 18 Polyhalogenated Aromatic Hydrocarbons
Authors: Yeatts Sharon D. , Gennings Chris , Crofton Kevin M.
Published: May 2012

Traditional additivity models provide little flexibility in modeling the dose–response relationships of the single agents in a mixture. While the flexible single chemical required (FSCR) methods allow greater flexibility, its implicit nature is an obstacle in the formation of the parameter covariance matrix, which forms the basis for many statistical optimality design criteria. The goal of this effort is to develop a method for constructing the parameter covariance matrix for the FSCR models, so that (local) alphabetic optimality criteria can be applied. Data from Crofton et al. are provided as motivation; in an experiment designed to determine the effect of 18 polyhalogenated aromatic hydrocarbons on serum total thyroxine (T4), the interaction among the chemicals was statistically significant. Gennings et al. fit the FSCR interaction threshold model to the data. The resulting estimate of the interaction threshold was positive and within the observed dose region, providing evidence of a dose‐dependent interaction. However, the corresponding likelihood‐ratio‐based confidence interval was wide and included zero. In order to more precisely estimate the location of the interaction threshold, supplemental data are required. Using the available data as the first stage, the Ds‐optimal second‐stage design criterion was applied to minimize the variance of the hypothesized interaction threshold. Practical concerns associated with the resulting design are discussed and addressed using the penalized optimality criterion. Results demonstrate that the penalized Ds‐optimal second‐stage design can be used to more precisely define the interaction threshold while maintaining the characteristics deemed important in practice.
Managing Employee Compliance with Information Security Policies: The Critical Role of Top Management and Organizational Culture*
Authors: Hu Qing , Dinev Tamara , Hart Paul , Cooke Donna
Published: May 2012

We develop an individual behavioral model that integrates the role of top management and organizational culture into the theory of planned behavior in an attempt to better understand how top management can influence security compliance behavior of employees. Using survey data and structural equation modeling, we test hypotheses on the relationships among top management participation, organizational culture, and key determinants of employee compliance with information security policies. We find that top management participation in information security initiatives has significant direct and indirect influences on employees’ attitudes towards, subjective norm of, and perceived behavioral control over compliance with information security policies. We also find that the top management participation strongly influences organizational culture which in turn impacts employees’ attitudes towards and perceived behavioral control over compliance with information security policies. Furthermore, we find that the effects of top management participation and organizational culture on employee behavioral intentions are fully mediated by employee cognitive beliefs about compliance with information security policies. Our findings extend information security research literature by showing how top management can play a proactive role in shaping employee compliance behavior in addition to the deterrence oriented remedies advocated in the extant literature. Our findings also refine the theories about the role of organizational culture in shaping employee compliance behavior. Significant theoretical and practical implications of these findings are discussed.
Integration of clinical and imaging data to predict death in hemodialysis patients
Authors: Bellasi Antonio , Block Geoffrey A. , Ferramosca Emiliana , Ratti Carlo , Raggi Paolo
Published: May 2012

In a prior publication, we demonstrated that a model integrating clinical and simple imaging data predicted the presence and severity of coronary artery calcification in prevalent hemodialysis patients. Herein we report the ability of the same model to predict all‐cause death. We assessed all‐cause mortality in 141 consecutive maintenance hemodialysis patients from two dialysis centers followed for a median of 79 months from enrollment. Patients were risk stratified according to a simple cardiovascular calcification index (CCI) that included patient's age, dialysis vintage, calcification of the cardiac valves, and abdominal aorta. The mean patients’ age was 55 ± 14 years. Abdominal aorta calcification was present in 57% of the patients, and 44% and 38% had aortic and mitral valve calcification, respectively. During follow‐up, 75 deaths (93 deaths per 1000 person‐years) were recorded. The CCI was linearly associated with risk of death, such that the unadjusted hazard risk (HR) increased by 12% for each point increase in CCI (P < 0.001). Further adjustments for age, sex, study center, diabetes mellitus, history of cardiovascular disease, hypertension, congestive heart failure, left ventricular hypertrophy, systolic, and diastolic blood pressure did not substantially change the strength of this association (HR 1.10; 95%CI: 1.00–1.21; P = 0.03). The CCI is a simple clinical model that can be used to risk stratify maintenance hemodialysis patients.
Heparin‐induced thrombocytopenia in a hemodialysis patient treated with fondaparinux: Nephrologists between two fires
Authors: Solak Yalcin , Demircioglu Sinan , Polat Ilker , Biyik Zeynep , Gaipov Abduzhappar , Acar Kadir , Turk Suleyman
Published: May 2012

Heparin‐induced thrombocytopenia (HIT) is caused by heparin exposure and presents with reduced platelet count. Patients undergoing hemodialysis (HD) treatment have increased risk of developing HIT due to prolonged exposure to unfractionated heparin or low‐molecular weight heparin. We report a 79‐year‐old male patient with end‐stage renal disease who developed type‐II HIT during maintenance HD. Platelet count of the patient decreased gradually and antiplatelet factor IV antibody was found to be positive. The patient was treated with fondaparinux and continued heparin‐free HD. Unfortunately, despite favorable initial response without any thrombotic episodes, the patient died due to severe sepsis complicated by gastrointestinal hemorrhage.
Cell–Cell Communication in the Resistance Vasculature: The Past, Present, and Future
Authors: WELSH DONALD G. , TAYLOR MARK S.
Published: May 2012

Please cite this paper as: Welsh DG, Taylor MS. Cell–cell communication in the resistance vasculature: the past, present, and future. Microcirculation 19: 377–378, 2012.

Cell–cell communication among neighboring vascular cells plays an important role in blood flow control. In this overview, we highlight a series of expert opinion articles focused on key issues related to the foundational nature and functional importance of electrical and second messenger communication. These manuscripts are written in an opinionated manner to provoke thought and to illuminate new emerging areas of investigation.
Nanostructured Photocatalysts with Enhanced Visible‐Light Activity by a Low‐Temperature Sol‐Gel Process
Authors: Tung Wing Sze , Daoud Walid A.
Published: May 2012

Visible‐light active titanium dioxide catalysts were obtained using a single chemical doping process. In contrast to reported doping approaches, a low‐temperature sol‐gel doping process was developed. The photocatalytic efficiency was evaluated through the degradation of methylene blue and methyl orange under UV and visible light irradiation, wherein doped titanium dioxide catalysts outperformed Degussa P‐25. The structure of the synthesized catalysts was investigated using Fourier transformation infrared, X‐ray diffraction, transmission electron microscopy, and selected area electron diffraction. The elemental composition of the resulting catalysts was characterized by X‐ray photoelectron spectroscopy. The optical absorption of the catalysts is also discussed.
Multifractal Analysis of Calcium Silicate Hydrate (C–S–H) Mapped by X‐ray Diffraction Microtomography
Authors: Valentini Luca , Artioli Gilberto , Voltolini Marco , Dalconi Maria Chiara
Published: May 2012

An investigation of Calcium Silicate Hydrate (C–S–H) topological distribution and modes of precipitation is performed by combining X‐ray powder diffraction tomography, performed on an ordinary Portland cement sample, with a numerical scheme that simulates C–S–H precipitation. C–S–H distribution maps obtained both experimentally and numerically are analyzed by means of a quantitative method based on the principles of multifractal systems. The combination of these methods allows C–S–H spatial distribution and modes of precipitation and aggregation to be assessed quantitatively. In particular, the multifractal spectra obtained from the digital images of the cement paste microstructure, act as a structural probe, which is able to quantify the tendency of C–S–H to form clusters. The results of this combined approach suggest that a multifractal network forms by aggregation of C–S–H clusters heterogeneously nucleated on clinker grains and preexisting clusters that are partly homogeneously nucleated in the porous space.
The Effect of Cation Distribution on Magnetic and Infrared Emission Properties of RE3+, MnO2:CoZn (RE = La,Ce,Pr,Nd,Sm,Eu,Gd,Tb, and Dy) Ferrite Ceramics
Authors: Zhang Ying , Wen Dijiang
Published: May 2012

The RE3+, MnO2:CoZn (RE = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, and Dy) ferrite ceramics were prepared by solid‐state reaction method. The change in the magnetic and infrared emission properties of the samples due to the co‐doping of RE3+ and Mn4+ ions have been studied. X‐ray diffraction studies show that the main phase of the system is the spinel phase and the secondary phase (REFeO3) is formed on co‐doping of RE3+ and Mn4+ ions. The distribution of cation in the tetrahedral and octahedral sites was analyzed using X‐ray photoelectron spectroscopy and Mössbauer spectroscopy. It was observed that larger RE3+ ions easily occupy the interstitial sites or grain boundary, but not the octahedral sites of the spinel. Magnetic and infrared emission measurements indicate that saturation magnetization decreases and infrared emissivity and coercivity exhibit the nonlinear variations with kinds of RE3+ ions. The magnetic and infrared emission properties of samples seem to be greatly influenced by the cation distribution caused by synergistic effect of RE3+ and Mn4+ ions, in which the rare earth elements of La, Nd, and Gd play a more important role to improve the infrared emissivity and coercivity than others.
Influences of Temperature and Oxygen Partial Pressure on Mechanical Properties of La0.6Sr0.4Co1−yFeyO3−δ
Authors: Kimura Yuta , Kushi Takuto , Hashimoto Shin‐ichi , Amezawa Koji , Kawada Tatsuya
Published: May 2012

Young's and shear moduli and Poisson's ratio of La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF6428), La0.6Sr0.4CoO3−δ (LSC), and La0.6Sr0.4FeO3−δ (LSF) were investigated in the temperature range from room temperature to 1173 K and in the oxygen partial pressure, P(O2), range from 1 × 10−1 to 1 × 10−4 bar by the resonance method. The Young's and the shear moduli decreased with increasing temperature at low temperatures and drastically increased at intermediate temperatures. The drastic increase was associated with the second‐order phase transition. In contrast, the Poisson's ratios of LSCF6428, LSC, and LSF decreased around the phase transition temperature. The P(O2) dependence of the Young's and the shear moduli of LSCF6428 showed different tendencies depending on temperature. At 873 K, the Young's and the shear moduli were almost independent of P(O2), whereas they increased with decreasing P(O2) at 973 K. At 1073 K, they first increased with decreasing P(O2) under higher P(O2) and then gradually decreased under lower P(O2). At 1173 K, they monotonically decreased with decreasing P(O2). Such complicated P(O2) dependence were interpreted by complex influences of the phase transition, the chemical expansion and the variation of the oxygen nonstoichiometry and the cation mean valence.
In Situ Observations of Templated Grain Growth in (Na0.5K0.5)0.98Li0.02NbO3 Piezoceramics: Texture Development and Template–Matrix Interactions
Authors: Tutuncu Goknur , Chang Yunfei , Poterala Stephen , Messing Gary L. , Jones Jacob L.
Published: May 2012

Nucleation, texture development, and phase equilibria were observed during templated grain growth (TGG) of (Na0.5K0.5)0.98Li0.02NbO3 (NKLN) via in situ X‐ray diffraction (XRD). Initially, NaNbO3 templates and NKLN matrix powder exist as distinct phases with unique lattice parameters. Above 850°C, the templates and matrix begin to react via interdiffusion as characterized by an increase in diffuse scattering between the NaNbO3 and NKLN peaks. This process intensifies immediately prior to template growth, leading to merging of diffraction peaks for these two phases. TGG in this system is thus homoepitaxial in nature as it occurs after the NKLN matrix and NaNbO3 templates form a solid solution. The degree of alignment in the matrix phase is quantified in situ using the March–Dollase parameters r and f. The degree of orientation of the textured NKLN mirrors the initial alignment of the template particles (r ≈ 0.3), while the texture fraction f increases from 0.04 to ~0.67 after 3 h at 1138°C. This increase in texture fraction follows n = 1/3 power law kinetics consistent with liquid‐phase‐assisted normal grain growth on plate‐like templates. As the observed template–matrix interdiffusion and the onset of texture development proceed extremely rapidly, this work demonstrates the utility of in situ XRD for observing details of TGG that cannot easily be seen via ex situ methods.
Porous χ‐Al2O3 Flake Powder as Dye‐Fixing Materials for Inkjet Printing Paper
Authors: Yu Pei‐Ching , Chen Chih‐I , Yang Rung‐Je , Yen Fu‐Su , Max Yen Shih‐Tsung
Published: May 2012

Cationic additives are generally used in coated inkjet printing paper to improve water fastness. This study develops a coating for photographic inkjet printing paper that achieves good water fastness without cationic additives. Porous χ‐
Al

2

O

3 flake powder, which has high porosity, high specific surface area, and positive surface charges, is used as a pigment in the coating. The water fastness of prints is evaluated using an immersion method combined with the measurement of light absorbance of the water used for immersion. The results indicate that water fastness can be improved by introducing χ‐
Al

2

O

3 powder into the coating pigments. The intrinsic crevices and pores of χ‐
Al

2

O

3 provide concave sites for dye colorants and enhance the sorbtion of liquid phase of inks, but stick the dye colorants on the pigment surface. Furthermore, the positive surface charge of χ‐
Al

2

O

3 provides cationic sites for the fixation of dye on the coating surface via electrostatic interactions.
Synthesis of Pure YB4 Powder via the Reaction of Y2O3 with B4C
Authors: Li Junguo , Peng Aiyi , He Yong , Yuan Huiping , Guo Qilong , Shen Qiang , Zhang Liangmeng
Published: May 2012

Pure YB4 powder was synthesized via the reaction of Y2O3 with B4C under a vacuum pressure within the range of 20–50 Pa using spark plasma sintering (SPS) route. The effect of temperature and the molar ratio of the starting materials was studied. The role of the YBO3, an intermediate product, in the synthesis of YB4 was investigated. For preparation of high purity YB4, the molar proportion of B4C to Y2O3 should not be higher than the stoichiometric ratio (15/7). YBO3 can be removed through decomposing to Y2O3 and B2O3 or reacting with B4C to form YB4 and B2O3 at a temperature above 1650°C. The little residual impurities, such as Y2O3 and YBO3, can be removed by hydrochloric acid washing. Thus, a high purity YB4 powder has been synthesized. The oxygen content of the obtained YB4 is about 0.007% and the particle size is in the range of 3–10 μm.
Nickel allergy in relation to piercing and orthodontic appliances – a population study
Authors: Fors Ronny , Stenberg Berndt , Stenlund Hans , Persson Maurits
Published: May 2012

Background. Studies have shown conflicting results on the association between nickel exposure from orthodontic appliances and nickel sensitization.

Objectives & Method. In a cross‐sectional study, we investigated the association between nickel sensitization and exposure to orthodontic appliances and piercings. 4376 adolescents were patch tested following a questionnaire asking for earlier piercing and orthodontic treatment. Exposure to orthodontic appliances was verified in dental records.

Results. Questionnaire data demonstrated a reduced risk of nickel sensitization when orthodontic treatment preceded piercing (OR 0.46; CI 0.27–0.78). Data from dental records demonstrated similar results (OR 0.61, CI 0.36–1.02), but statistical significance was lost when adjusting for background factors. Exposure to full, fixed appliances with NiTi‐containing alloys (OR 0.31, CI 0.10–0.98) as well as a pooled ‘high nickel‐releasing’ appliance group (OR 0.56, CI 0.32–0.97) prior to piercing was associated with a significantly reduced risk of nickel sensitization.

Conclusion. High nickel‐containing orthodontic appliances preceding piercing reduces the risk of nickel sensitization by a factor 1.5–2. The risk reduction is associated with estimated nickel release of the appliance and length of treatment. Sex, age at piercing and number of piercings are also important risk indicators. Research on the role of dental materials in the development of immunological tolerance is needed.
Landscape‐ and small‐scale determinants of grassland species diversity: direct and indirect influences
Authors: Gazol Antonio , Tamme Riin , Takkis Krista , Kasari Liis , Saar Liina , Helm Aveliina , Pärtel Meelis
Published: May 2012

Species richness is influenced both by mechanisms occurring at landscape scales, such as habitat availability, and local‐scale processes, that are related to abiotic conditions and plant–plant interactions. However, it is rarely tested to what extent local species richness can be explained by the combined effect of factors measured at multiple spatial scales. In this study, we quantified the simultaneous influence of historical landscape‐scale factors (past human population density, and past habitat availability – an index combining area and connectivity) and small‐scale environmental conditions (shrub cover, and heterogeneity of light, soil depth, and other soil environmental variables) on plant species richness in dry calcareous grasslands (alvars). By applying structural equation modelling (SEM) we found that both landscape conditions and local environmental factors had significant direct and indirect (i.e. through the modification of another factor), effects on species richness. At the landscape scale, we found a direct positive influence of historical habitat availability on species richness, and indirect positive influence of past human population (via its effects on historical habitat availability). At small scales, we found a positive direct influence of light heterogeneity and shrub cover on species richness. Conversely, we found that small‐scale soil environmental heterogeneity, which was mainly determined by soil depth heterogeneity, had a negative effect on species richness. Our study indicates that patterns of species richness in alvar grasslands are positively influenced by the anthropogenic management regime that maintained the landscape habitat conditions in the past. However, the abandonment of management, leading to shrub invasion and increased competition for light resources also influenced species richness. In contrast to the positive heterogeneity–diversity relationship we found that soil heterogeneity reduced species richness. Environmental heterogeneity, occurring at the plant neighbourhood scale (i.e. centimetres), can increase the isolation among suitable soil patches and thus hinder the normal functioning of populations. The combination of previous knowledge of the system with new ecological theories facilitates disentangling how species richness responds to complex relationships among factors operating at multiple scales.
Rituximab‐induced thrombocytopenia: a cohort study
Authors: Giezen Thijs J. , Mantel‐Teeuwisse Aukje K. , ten Berg Maarten J. , Straus Sabine M. J. M. , Leufkens Hubert G. M. , van Solinge Wouter W. , Egberts Toine C. G.
Published: May 2012

The combined information of drug exposure and laboratory test results on an individual patient level obtained in daily clinical practice can add important information about the safety of a drug. Thrombocytopenia is a known adverse drug reaction of rituximab, which has already been identified during the preregistration trials, but knowledge on incidence and risk factors in clinical practice is limited. We, therefore, aimed to estimate the incidence and explore the risk factors for the development of rituximab‐induced thrombocytopenia (a platelet count, <100 × 109 platelets/L) in clinical practice. Ninety patients were eligible for inclusion of which 27 developed thrombocytopenia (cumulative incidence, 30%) within 30 days after administration of rituximab and 18 patients developed grade 3/4 thrombocytopenia (cumulative incidence, 20%). Patients with and without thrombocytopenia were compared to explore risk factors. Patients with a relatively low platelet count (217 vs. 324 × 109/L, P = 0.011) before administration of rituximab had a higher risk for the development of thrombocytopenia, and although not statistically significant, patients treated with rituximab within the oncology setting (OR, 4.7; 95% CI, 1.0–23.3), independent of concomitant use of cytostatics, as compared to the autoimmune diseases and patients with a high platelet distribution width (PDW) (16.1 vs. 15.8, P = 0.051). In conclusion, the incidence of rituximab‐induced thrombocytopenia was higher than that identified during the clinical trials. Healthcare professionals should consider thrombocytopenia as a relevant reaction during treatment with rituximab. More frequent monitoring of the platelet count is especially advised in patients treated in the oncology indication and/or with a low platelet count and high PDW.
Polypodium leucotomos decreases UV‐induced epidermal cell proliferation and enhances p53 expression and plasma antioxidant capacity in hairless mice
Authors: Rodríguez‐Yanes Esperanza , Juarranz Ángeles , Cuevas Jesús , Gonzalez Salvador , Mallol Jordi
Published: May 2012

A single dose of ultraviolet radiation (UVR) induces significant changes in blood and skin of hairless mice. Oral administration of a hydrophilic extract of the fern Polypodium leucotomos (PL, 300 mg/kg during 5 days before UVR and for two additional days after irradiation) modulates some of the effects of UVR. Most significantly, PL administration reduced the number of proliferating cells by 13%, increased the number of p53+ cells by 63%, enhanced the antioxidant plasma capacity (ORAC) by 30% and reinforced the network of dermal elastic fibres. Western blot analysis of skin antioxidant‐related enzymes failed to demonstrate significant changes caused by PL. Thus, the beneficial effect of PL likely owes to its antioxidant and anti‐ROS properties rather than its modulation of the expression of endogenous antioxidant systems. These data provide mechanistic clues for its efficacy as a systemic photoprotective agent with antioxidant and anti‐photo‐ageing properties.