bluuebunny/crossref_metadata_2025 huggingface dataset:
Munc18b is an essential gene in mice whose expression is limiting for secretion by airway epithelial and mast cells
Authors: Kim Kyubo , Petrova Youlia M. , Scott Brenton L. , Nigam Rupesh , Agrawal Anurag , Evans Christopher M. , Azzegagh Zoulikha , Gomez Alejandra , Rodarte Elsa M. , Olkkonen Vesa M. , Bagirzadeh Rustam , Piccotti Lucia , Ren Binhui , Yoon Joo-Heon , McNew James A. , Adachi Roberto , Tuvim Michael J. , Dickey Burton F.
Published: June 2012

Airway mucin secretion and MC (mast cell) degranulation must be tightly controlled for homoeostasis of the lungs and immune system respectively. We found the exocytic protein Munc18b to be highly expressed in mouse airway epithelial cells and MCs, and localized to the apical pole of airway secretory cells. To address its functions, we created a mouse with a severely hypomorphic Munc18b allele such that protein expression in heterozygotes was reduced by ~50%. Homozygous mutant mice were not viable, but heterozygotes showed a ~50% reduction in stimulated release of mucin from epithelial cells and granule contents from MCs. The defect in MCs affected only regulated secretion and not constitutive or transporter-mediated secretion. The severity of passive cutaneous anaphylaxis was also reduced by ~50%, showing that reduction of Munc18b expression results in an attenuation of physiological responses dependent on MC degranulation. The Munc18b promoter is controlled by INR (initiator), Sp1 (specificity protein 1), Ets, CRE (cAMP-response element), GRE (glucocorticoid-response element), GATA and E-box elements in airway epithelial cells; however, protein levels did not change during mucous metaplasia induced by allergic inflammation. Taken together, the results of the present study identify Munc18b as an essential gene that is a limiting component of the exocytic machinery of epithelial cells and MCs.
AMP-activated protein kinase: new regulation, new roles?
Authors: Carling David , Thornton Claire , Woods Angela , Sanders Matthew J.
Published: June 2012

The hydrolysis of ATP drives virtually all of the energy-requiring processes in living cells. A prerequisite of living cells is that the concentration of ATP needs to be maintained at sufficiently high levels to sustain essential cellular functions. In eukaryotic cells, the AMPK (AMP-activated protein kinase) cascade is one of the systems that have evolved to ensure that energy homoeostasis is maintained. AMPK is activated in response to a fall in ATP, and recent studies have suggested that ADP plays an important role in regulating AMPK. Once activated, AMPK phosphorylates a broad range of downstream targets, resulting in the overall effect of increasing ATP-producing pathways whilst decreasing ATP-utilizing pathways. Disturbances in energy homoeostasis underlie a number of disease states in humans, e.g. Type 2 diabetes, obesity and cancer. Reflecting its key role in energy metabolism, AMPK has emerged as a potential therapeutic target. In the present review we examine the recent progress aimed at understanding the regulation of AMPK and discuss some of the latest developments that have emerged in key areas of human physiology where AMPK is thought to play an important role.
Proteomic analysis of endogenous nitrotryptophan-containing proteins in rat hippocampus and cerebellum
Authors: Uda Munehiro , Kawasaki Hiroaki , Shigenaga Ayako , Baba Takeshi , Yamakura Fumiyuki
Published: June 2012

Nitration of tryptophan residues is a novel post-translational modification. In the present study, we examined whether NO2Trp (nitrotryptophan)-containing proteins are produced in the hippocampus and cerebellum of the adult rat under physiological conditions in vivo. Using Western blot analysis with anti-6-NO2Trp-specific antibody, we found many similar immunoreactive spots in the protein extracts from both regions. These spots were subsequently subjected to trypsin digestion and LC-ESI-MS/MS (LC-electrospray ionization-tandem MS) analysis. We identified several cytoskeletal proteins and glycolytic enzymes as NO2Trp-containing proteins and determined the position of nitrated tryptophan residues with significant ion score levels (P<0.05) in several proteins in both regions. We also observed that the total amount of NO2Trp-containing proteins in the cerebellum was significantly greater than that in the hippocampus (P<0.05). Moreover, IP (immunoprecipitation) assays using anti-aldolase C antibody showed that the relative intensity of immunostaining for NO2Trp over aldolase C was much higher in cerebellum than in hippocampus. The amounts of nNOS (neuronal nitric oxide synthase) and eNOS (endothelial nitric oxide synthase) were much greater in cerebellum than in hippocampus. This is the first evidence of several specific sites of nitrated tryptophan in proteins under physiological conditions in vivo.
A single ligand is sufficient to activate EGFR dimers
Authors: Liu Ping , Cleveland Thomas E. , Bouyain Samuel , Byrne Patrick O. , Longo Patti A. , Leahy Daniel J.
Published: June 2012

Crystal structures of human epidermal growth factor receptor (EGFR) with bound ligand revealed symmetric, doubly ligated receptor dimers thought to represent physiologically active states. Such complexes fail to rationalize negative cooperativity of epidermal growth factor (EGF) binding to EGFR and the behavior of the ligandless EGFR homolog ErbB2/HER2, however. We report cell-based assays that provide evidence for active, singly ligated dimers of human EGFR and its homolog, ErbB4/HER4. We also report crystal structures of the ErbB4/HER4 extracellular region complexed with its ligand Neuregulin-1β that resolve two types of ErbB dimer when compared to EGFR:Ligand complexes. One type resembles the recently reported asymmetric dimer of
Drosophila
EGFR with a single high-affinity ligand bound and provides a model for singly ligated human ErbB dimers. These results unify models of vertebrate and invertebrate EGFR/ErbB signaling, imply that the tethered conformation of unliganded ErbBs evolved to prevent crosstalk among ErbBs, and establish a molecular basis for both negative cooperativity of ligand binding to vertebrate ErbBs and the absence of active ErbB2/HER2 homodimers in normal conditions.
A study of nanoellipsoids for thin-film plasmonic solar cell applications
Authors: Ji Alok , Sangita  , Sharma R P
Published: June 2012

Metal nanoparticles (MNPs) support surface plasmon modes, which are used to couple light into the underlying optical modes of a semiconductor. In this paper, we investigate the suitability of localized surface plasmons to enhance the scattering efficiency of incident light from a silver nanoellipsoid and hence its absorption into silicon solar cells. Light scattering efficiency of the silver nanoellipsoid was calculated based on a quasi-static approximation. We found that the silver nanoellipsoid may be tuned to have higher scattering efficiency in the near infrared region. In this work the particle size, shape, aspect ratio and the distance of the nanoellipsoid from the substrate were varied to study their impact on light trapping in solar cells. We found that the nanoellipsoid (oblate) is more suitable to tune the resonance near the band gap of silicon as compared with a nanosphere. Calculations show that the desired resonance (around 1000 nm) can be achieved with aspect ratio lying in the domain 0.3–0.4 with a particle size of 15 nm and distance between substrate and nanoellipsoid of around 2–3 nm.
Dynamics of ionization wave splitting and merging of atmospheric-pressure plasmas in branched dielectric tubes and channels
Authors: Xiong Zhongmin , Robert Eric , Sarron Vanessa , Pouvesle Jean-Michel , Kushner Mark J
Published: June 2012

Atmospheric-pressure fast ionization waves (FIWs) generated by nanosecond, high voltage pulses are able to propagate long distances through small diameter dielectric tubes or channels, and so deliver UV fluxes, electric fields, charged and excited species to remote locations. In this paper, the dynamics of FIW splitting and merging in a branched dielectric channel are numerically investigated using a two-dimensional plasma hydrodynamics model with radiation transport, and the results are compared with experiments. The channel consists of a straight inlet section branching 90° into a circular loop which terminates to form a second straight outlet section aligned with the inlet section. The plasma is sustained in neon gas with a trace amount of xenon at atmospheric pressure. The FIW generated at the inlet approaches the first branch point with speeds of ≈108 cm s−1, and produces a streamer at the inlet–loop junction. The induced streamer then splits into two FIW fronts, each propagating in opposite directions through half of the loop channel. The FIWs slow as they traverse the circular sections due to a shorting of the electric field by the other FIW. Approaching the loop–outlet junction, the two FIW fronts nearly come to a halt, induce another streamer which goes through further splitting and finally develops into a new FIW front. The new FIW increases in speed and plasma density propagating in the straight outlet channel. The electrical structure of the FIWs and the induced streamers during the splitting and merging processes are discussed with an emphasis on their mutual influence and their interaction with the channel wall. The FIW propagation pattern is in good agreement with experimental observations. Based on numerical and experimental investigations, a model for the splitting and merging FIWs in the branched loop channel is proposed.
Nanomechanical properties of lithiated Si nanowires probed with atomic force microscopy
Authors: Lee Hyunsoo , Shin Weonho , Choi Jang Wook , Park Jeong Young
Published: June 2012

The nanomechanical properties of fully lithiated and pristine Si nanowires (NWs) deposited on a Si substrate were studied with atomic force microscopy (AFM). Si NWs were synthesized using the vapour–liquid–solid process on stainless-steel substrates using an Au catalyst. Fully lithiated Si NWs were obtained using the electrochemical method, followed by drop-casting on a Si substrate. The roughness of the Si NWs, which was derived from AFM images, is greater for the lithiated Si NWs than for the pristine Si NWs. Force spectroscopy was used to study the influence of lithiation on the tip–surface adhesion force. The lithiated Si NWs revealed a smaller tip–surface adhesion force than the Si substrate by a factor of two, while the adhesion force of the Si NWs is similar to that of the Si substrate. Young's modulus, obtained from the force–distance curve, also shows that the pristine Si NWs have a relatively higher value than the lithiated Si NWs due to the elastically soft and amorphous structures of the lithiated region. These results suggest that force spectroscopy can be used to probe the degree of lithiation at nanometer scale during the charging and discharging processes.
A hybrid heterojunction with reverse rectifying characteristics fabricated by magnetron sputtered TiOx and plasma polymerized aniline structure
Authors: Sarma Bimal K , Pal Arup R , Bailung Heremba , Chutia Joyanti
Published: June 2012

A TiO
x
film produced by direct current reactive magnetron sputtering without substrate heating or post-deposition annealing and a plasma polymerized aniline (PPA) structure deposited in the same reactor by a radio-frequency glow discharge without the assistance of a carrier gas are used for the fabrication of a heterojunction. The gas phase discharge is investigated by a Langmuir probe and optical emission spectroscopy. The individual layers and the heterojunction are characterized for structural and optoelectronic properties. PPA has polymer-like structure and texture and is characterized by saturated–unsaturated, branched and crosslinked networks. X-ray photoelectron spectroscopy reveals a slightly reduced TiO
x
surface, which exhibits near band edge luminescence. The free radicals trapped in PPA readily react with oxygen when exposed to atmosphere. The heterojunction shows reverse rectifying characteristics under dark and ultraviolet (UV) irradiation. The energy levels of TiO
x
and PPA might exhibit reverse band bending and electrons and holes are accumulated on both sides of the heterojunction. The charge accumulation phenomena at the interface may play a key role in the device performance of a hybrid heterojunction. The current–voltage characteristic of the heterojunction is sensitive to UV light, so the structure may be used for photo-sensing applications.
On the spherically symmetric Einstein–Yang–Mills–Higgs equations in Bondi coordinates
Authors: Tadmon Calvin , Tchapnda Sophonie Blaise
Published: June 2012

We revisit and generalize, to the Einstein–Yang–Mills–Higgs (EYMH) system, previous results of Christodoulou and Chae concerning global solutions for the Einstein-scalar field and the Einstein–Maxwell–Higgs (EMH) equations. The novelty of the present work is twofold. For one thing, the assumption on the self-interaction potential is improved. For another thing, explanation is furnished why the solutions obtained here and those proved by Chae for the EMH system decay more slowly than those established by Christodoulou in the case of self-gravitating scalar fields. Actually, this latter phenomenon stems from the non-vanishing local charge in EMH and EYMH models.
Genic and nongenic contributions to natural variation of quantitative traits in maize
Authors: Li Xianran , Zhu Chengsong , Yeh Cheng-Ting , Wu Wei , Takacs Elizabeth M. , Petsch Katherine A. , Tian Feng , Bai Guihua , Buckler Edward S. , Muehlbauer Gary J. , Timmermans Marja C.P. , Scanlon Michael J. , Schnable Patrick S. , Yu Jianming
Published: June 2012

The complex genomes of many economically important crops present tremendous challenges to understand the genetic control of many quantitative traits with great importance in crop production, adaptation, and evolution. Advances in genomic technology need to be integrated with strategic genetic design and novel perspectives to break new ground. Complementary to individual-gene–targeted research, which remains challenging, a global assessment of the genomic distribution of trait-associated SNPs (TASs) discovered from genome scans of quantitative traits can provide insights into the genetic architecture and contribute to the design of future studies. Here we report the first systematic tabulation of the relative contribution of different genomic regions to quantitative trait variation in maize. We found that TASs were enriched in the nongenic regions, particularly within a 5-kb window upstream of genes, which highlights the importance of polymorphisms regulating gene expression in shaping the natural variation. Consistent with these findings, TASs collectively explained 44%–59% of the total phenotypic variation across maize quantitative traits, and on average, 79% of the explained variation could be attributed to TASs located in genes or within 5 kb upstream of genes, which together comprise only 13% of the genome. Our findings suggest that efficient, cost-effective genome-wide association studies (GWAS) in species with complex genomes can focus on genic and promoter regions.
Kv4 potassium channels modulate hippocampal EPSP-spike potentiation and spatial memory in rats
Authors: Truchet Bruno , Manrique Christine , Sreng Leam , Chaillan Franck A. , Roman François S. , Mourre Christiane
Published: June 2012

Kv4 channels regulate the backpropagation of action potentials (b-AP) and have been implicated in the modulation of long-term potentiation (LTP). Here we showed that blockade of Kv4 channels by the scorpion toxin AmmTX3 impaired reference memory in a radial maze task. In vivo, AmmTX3 intracerebroventricular (i.c.v.) infusion increased and stabilized the EPSP-spike (E-S) component of LTP in the dentate gyrus (DG), with no effect on basal transmission or short-term plasticity. This increase in E-S potentiation duration could result from the combination of an increase in excitability of DG granular cells with a reduction of GABAergic inhibition, leading to a strong reduction of input specificity. Radioactive in situ hybridization (ISH) was used to evaluate the amounts of Kv4.2 and Kv4.3 mRNA in brain structures at different stages of a spatial learning task in naive, pseudoconditioned, and conditioned rats. Significant differences in Kv4.2 and Kv4.3 mRNA levels were observed between conditioned and pseudoconditioned rats. Kv4.2 and Kv4.3 mRNA levels were transiently up-regulated in the striatum, nucleus accumbens, retrosplenial, and cingulate cortices during early stages of learning, suggesting an involvement in the switch from egocentric to allocentric strategies. Spatial learning performance was positively correlated with the levels of Kv4.2 and Kv4.3 mRNAs in several of these brain structures. Altogether our findings suggest that Kv4 channels could increase the signal-to-noise ratio during information acquisition, thereby allowing a better encoding of the memory trace.
Tumor suppressor TAp73 gene specifically responds to deregulated E2F activity in human normal fibroblasts
Authors: Ozono Eiko , Komori Hideyuki , Iwanaga Ritsuko , Tanaka Tatsuya , Sakae Takahiro , Kitamura Hodaka , Yamaoka Shoji , Ohtani Kiyoshi
Published: June 2012

Discrimination of oncogenic growth signals from normal growth signals is crucial for tumor suppression. The transcription factor E2F, the main target of pRB, plays central role in cell proliferation by activating growth‐promoting genes. E2F also plays an important role in tumor suppression by activating growth‐suppressive genes such as pro‐apoptotic genes. The regulatory mechanism of the latter genes is not known in detail, especially in response to normal and oncogenic growth signals. E2F is physiologically activated by growth stimulation through phosphorylation of pRB. In contrast, upon dysfunction of pRB, a major oncogenic change, E2F is activated out of control by pRB, generating deregulated E2F activity. We show here that the tumor suppressor TAp73 gene, which can induce apoptosis independently of p53, responds to deregulated E2F activity, but not to physiological E2F activity induced by growth stimulation in human normal fibroblasts. We identified E2F‐responsive elements (ERE73s) in TAp73 promoter that can specifically sense deregulated E2F activity. Moreover, RB1‐deficient cancer cell lines harbored deregulated E2F activity that activated ERE73s and the TAp73 gene, which were suppressed by re‐introduction of pRB. These results underscore the important role of deregulated E2F in activation of the TAp73 gene, a component of major intrinsic tumor suppressor pathways.
Joint estimation of habitat dynamics and species interactions: disturbance reduces co‐occurrence of non‐native predators with an endangered toad
Authors: Miller David A. W. , Brehme Cheryl S. , Hines James E. , Nichols James D. , Fisher Robert N.
Published: June 2012

1. Ecologists have long been interested in the processes that determine patterns of species occurrence and co‐occurrence. Potential short‐comings of many existing empirical approaches that address these questions include a reliance on patterns of occurrence at a single time point, failure to account properly for imperfect detection and treating the environment as a static variable.

2. We fit detection and non‐detection data collected from repeat visits using a dynamic site occupancy model that simultaneously accounts for the temporal dynamics of a focal prey species, its predators and its habitat. Our objective was to determine how disturbance and species interactions affect the co‐occurrence probabilities of an endangered toad and recently introduced non‐native predators in stream breeding habitats. For this, we determined statistical support for alternative processes that could affect co‐occurrence frequency in the system.

3. We collected occurrence data at stream segments in two watersheds where streams were largely ephemeral and one watershed dominated by perennial streams. Co‐occurrence probabilities of toads with non‐native predators were related to disturbance frequency, with low co‐occurrence in the ephemeral watershed and high co‐occurrence in the perennial watershed. This occurred because once predators were established at a site, they were rarely lost from the site except in cases when the site dried out. Once dry sites became suitable again, toads colonized them much more rapidly than predators, creating a period of predator‐free space.

4. We attribute the dynamics to a storage effect, where toads persisting outside the stream environment during periods of drought rapidly colonized sites when they become suitable again. Our results support that even in highly connected stream networks, temporal disturbance can structure frequencies with which breeding amphibians encounter non‐native predators.

5. Dynamic multi‐state occupancy models are a powerful tool for rigorously examining hypotheses about inter‐species and species–habitat interactions. In contrast to previous methods that infer dynamic processes based on static patterns in occupancy, the approach we took allows the dynamic processes that determine species–species and species–habitat interactions to be directly estimated.
Measuring ectomycorrhizal fungal dispersal: macroecological patterns driven by microscopic propagules
Authors: PEAY KABIR G. , SCHUBERT MAX G. , NGUYEN NHU H. , BRUNS THOMAS D.
Published: June 2012

Dispersal plays a prominent role in most conceptual models of community assembly. However, direct measurement of dispersal across a whole community is difficult at ecologically relevant spatial scales. For cryptic organisms, such as fungi and bacteria, the scale and importance of dispersal limitation has become a major point of debate. We use an experimental island biogeographic approach to measure the effects of dispersal limitation on the ecological dynamics of an important group of plant symbionts, ectomycorrhizal fungi. We manipulated the isolation of uncolonized host seedlings across a natural landscape and used a range of molecular techniques to measure the dispersal rates of ectomycorrhizal propagules and host colonization. Some species were prolific dispersers, producing annual spore loads on the order of trillions of spores per km2. However, fungal propagules reaching host seedlings decreased rapidly with increasing distance from potential spore sources, causing a concomitant reduction in ectomycorrhizal species richness, host colonization and host biomass. There were also strong differences in dispersal ability across species, which correlated well with the predictable composition of ectomycorrhizal communities associated with establishing pine forest. The use of molecular tools to measure whole community dispersal provides a direct confirmation for a key mechanism underlying island biogeography theory and has the potential to make microbial systems a model for understanding the role of dispersal in ecological theory.
Binding of transcription factor activating protein 2 γ on the 5′‐proximal promoter region of human porcine endogenous retrovirus subgroup A receptor 2/GPR172B
Authors: Nakaya Yuki , Shimode Sayumi , Kobayashi Takeshi , Imakawa Kazuhiko , Miyazawa Takayuki
Published: June 2012

Nakaya Y, Shimode S, Kobayashi T, Imakawa K, Miyazawa T. Binding of transcription factor activating protein 2γ on the 5′‐proximal promoter region of human porcine endogenous retrovirus subgroup A receptor 2/GPR172B. Xenotransplantation 2012; 19: 177–185. © 2012 John Wiley & Sons A/S.

Abstract: Background:  Xenotransplantation is one of the solutions for the shortage of organ donors, and pigs have been considered to be the most suitable animal donors. Specific pathogen‐free pigs are utilized in the xenotransplantation; however, pigs have infectious gammaretroviruses, named porcine endogenous retroviruses (PERVs) in their genome. Of them, PERV‐A and PERV‐B can infect human cells in vitro and potentially induce diseases like other gammaretroviruses. The human cellular receptors for PERV‐A were identified and named human PERV‐A receptor (HuPAR)‐1 and HuPAR‐2 (also called as GPR172A and GPR172B, respectively). We have recently reported that HuPAR‐2 expression was regulated by epigenetic modification and preferentially expressed in placenta. However, the detailed mechanisms of HuPAR‐2 expression have not been fully characterized. In this study, we analyzed molecular mechanisms associated with HuPAR‐2 transcription through the identification of transcription factors that bind to the promoter region of HuPAR‐2.

Methods:  In situ hybridization was performed to identify the cells expressing HuPAR‐2 in placental tissues. Transcriptional activities were measured by dual‐luciferase reporter assay using serial deletion mutants of HuPAR‐2 5′‐flanking region. To identify the transcription factors bound to the promoter region, in silico analysis, electrophoresis mobility shift assay, and chromatin immunoprecipitation assay were conducted. The effect of the transcription factor transcription factor activator protein (TFAP)‐2γ on the promoter activities was investigated by overexpression of the factor.

Results:  We identified that HuPAR‐2 was specifically expressed in villous trophoblast cells. We also identified that a region spanning from −126 to −32 had proximal promoter activities and TFAP‐2γ bound to a region spanning from −58 to −35 in vitro and in vivo. The overexpression of TFAP‐2γ also augmented the proximal promoter activity.

Conclusion:  We demonstrated that TFAP‐2γ is one of the transcription factors involved in the HuPAR‐2 expression in human villous trophoblast cells. By studying transcriptional factors involved in the expression of HuPAR‐2, we may find a clue to control the potential risks caused by PERV‐A infection in xenotransplantation.
Health workforce changes and the roles of information technology associated with these changes. “The Times They Are A‐Changin' ” (Bob Dylan, 1964)
Authors: Hannan T. , Brooks P.
Published: June 2012

Healthcare is considered a service profession and most of what clinicians do is manage information. Thus, information is not a necessary adjunct to care. It is care and effective patient management that require effective management of patients' clinical data. This perspective is supported by the World Health Organisation in its use of the quotation from Gonzalo Vecina Neto, head of the Brazilian National Health Regulatory Agency, ‘There is no health without management, and there is no management without information’.

This opinion paper discusses how traditional clinical decision‐making led ‘by the doctor’ is unsustainable in the modern era and how e‐technologies will facilitate distributed effective decision‐making and new divisions of labour across the health workforce.
Implementation of standardised surveillance for Clostridium difficile infections in Australia: initial report from the Victorian Healthcare Associated Infection Surveillance System
Authors: Bull A. L. , Worth L. J. , Richards M. J.
Published: June 2012

Detection of a hypervirulent strain of Clostridium difficile in Victoria led to commencement of targeted surveillance for C. difficile infection in 2010. Cases were reported through the Victorian Healthcare Associated Infection Surveillance System. Between 1 October 2010 and 31 March 2011, 477 cases of C. difficile infection were identified; 11 (2.3%) secondary to a hypervirulent strain. Three hundred and seventy (1.7 per 10 000 occupied bed days) were healthcare associated. Data reflect successful implementation of continuous surveillance for C. difficile infection. With hypervirulent C. difficile infection now reported in other Australian states, development of a national data repository for C. difficile infection is necessary.
Point‐prevalence study of inappropriate antibiotic use at a tertiary Australian hospital
Authors: Ingram P. R. , Seet J. M. , Budgeon C. A. , Murray R.
Published: June 2012

A point‐prevalence study at a tertiary Australian hospital found 199 of 462 inpatients (43%) to be receiving antibiotic therapy. Forty‐seven per cent of antibiotic use was discordant with guidelines or microbiological results and hence considered inappropriate. Risk factors for inappropriate antibiotic prescribing included bone/joint infections, the absence of infection, creatinine level >120 µmol/L, carbapenem or macrolide use and being under the care of the aged care/rehabilitation team. In the setting of finite antimicrobial stewardship resources, identification of local determinants for inappropriate antibiotic use may enable more targeted interventions.
Delusions of Korean patients with Alzheimer's disease: Study of drug‐naïve patients
Authors: Kwak Yong Tae , Yang YoungSoon , Kwak Soon‐Gu , Koo Min‐Seong
Published: June 2012

Aim:  Although delusions are one of the most prominent psychiatric symptoms in Alzheimer's disease (AD), research on the subtypes, prevalence and associated factors of delusions, especially in drug (psychotropic)‐naïve patients, has been limited.

Methods:  Patients (n = 230) with psychotropic‐naïve (drug‐naïve) probable AD were assessed with the Korean Neuropsychiatric Inventory (K‐NPI) delusion subscale at the time of initial presentation. After determining the four delusion subtypes (paranoid, misidentification, mixed and expansive delusion), clinical characteristics and prevalence of each type were compared.

Results:  Delusions were present in 63 patients (27.4%). Among those patients, paranoid delusions were the most common type of delusion (38, 60.3%), followed by misidentification delusions (12, 19.0%), then mixed delusions (11, 17.5%). Expansive delusions are rare in drug‐naïve probable AD patients. Compared with paranoid delusions, misidentification and mixed delusions appeared at a later stage, and were associated with greater cognitive impairment. Mixed delusions were associated with hallucinations.

Conclusions:  This study showed that delusions are associated with global cognitive dysfunction. Although paranoid delusions are the most common, misidentification and mixed delusions comprised significant portions of delusions in AD patients, and appeared in the later stages of dementia. Geriatr Gerontol Int 2013; 13: 307–313.
Simultaneous application of slow‐oscillation transcranial direct current stimulation and theta burst stimulation prolongs continuous theta burst stimulation‐induced suppression of corticomotor excitability in humans
Authors: Doeltgen Sebastian H. , McAllister Suzanne M. , Ridding Michael C.
Published: June 2012

The objective of this study was to assess whether the simultaneous application of slow‐oscillation transcranial direct current stimulation enhances the neuroplastic response to transcranial magnetic theta burst stimulation. Motor evoked potential amplitude was assessed at baseline and at regular intervals up to 60 min following continuous theta burst stimulation, slow‐oscillation transcranial direct current stimulation, and the simultaneous application of these paradigms. In addition, the electroencephalographic power spectra of slow and fast delta, and theta frequency bands recorded over the motor cortex were analyzed prior to and up to 5 min following each intervention. There was longer‐lasting motor evoked potential suppression following the simultaneous application of continuous theta burst stimulation and slow‐oscillation transcranial direct current stimulation compared with when continuous theta burst stimulation was applied alone. Slow‐oscillation transcranial direct current stimulation applied alone did not modulate the motor evoked potential amplitude. No significant changes in spectral power were observed following slow‐oscillation transcranial direct current stimulation. Simultaneous application of continuous theta burst stimulation and slow‐oscillation transcranial direct current stimulation may provide an approach to prolong the induction of neuroplastic changes in motor cortical circuits by repetitive transcranial magnetic brain stimulation.
Axonal properties determine somatic firing in a model of in vitro CA1 hippocampal sharp wave/ripples and persistent gamma oscillations
Authors: Traub Roger D. , Schmitz Dietmar , Maier Nikolaus , Whittington Miles A. , Draguhn Andreas
Published: June 2012

Evidence has been presented that CA1 pyramidal cells, during spontaneous in vitro sharp wave/ripple (SPW‐R) complexes, generate somatic action potentials that originate in axons. ‘Participating’ (somatically firing) pyramidal cells fire (almost always) at most once during a particular SPW‐R whereas non‐participating cells virtually never fire during an SPW‐R. Somatic spikelets were small or absent, while ripple‐frequency EPSCs and IPSCs occurred during the SPW‐R in pyramidal neurons. These experimental findings could be replicated with a network model in which electrical coupling was present between small pyramidal cell axonal branches. Here, we explore this model in more depth. Factors that influence somatic participation include: (i) the diameter of axonal branches that contain coupling sites to other axons, because firing in larger branches injects more current into the main axon, increasing antidromic firing probability; (ii) axonal K+ currents and (iii) somatic hyperpolarization and shunting. We predict that portions of axons fire at high frequency during SPW‐R, while somata fire much less. In the model, somatic firing can occur by occasional generation of full action potentials in proximal axonal branches, which are excited by high‐frequency spikelets. When the network contains phasic synaptic inhibition, at the axonal gap junction site, gamma oscillations result, again with more frequent axonal firing than somatic firing. Combining the models, so as to generate gamma followed by sharp waves, leads to strong overlap between the population of cells firing during gamma and the population of cells firing during a subsequent sharp wave, as observed in vivo.
Structuring of bacterioplankton communities by specific dissolved organic carbon compounds
Authors: Gómez‐Consarnau Laura , Lindh Markus V. , Gasol Josep M. , Pinhassi Jarone
Published: June 2012

The main role of microorganisms in the cycling of the bulk dissolved organic carbon pool in the ocean is well established. Nevertheless, it remains unclear if particular bacteria preferentially utilize specific carbon compounds and whether such compounds have the potential to shape bacterial community composition. Enrichment experiments in the Mediterranean Sea, Baltic Sea and the North Sea (Skagerrak) showed that different low‐molecular‐weight organic compounds, with a proven importance for the growth of marine bacteria (e.g. amino acids, glucose, dimethylsulphoniopropionate, acetate or pyruvate), in most cases differentially stimulated bacterial growth. Denaturing gradient gel electrophoresis ‘fingerprints’ and 16S rRNA gene sequencing revealed that some bacterial phylotypes that became abundant were highly specific to enrichment with specific carbon compounds (e.g. Acinetobacter sp. B1‐A3 with acetate or Psychromonas sp. B3‐U1 with glucose). In contrast, other phylotypes increased in relative abundance in response to enrichment with several, or all, of the investigated carbon compounds (e.g. Neptuniibacter sp. M2‐A4 with acetate, pyruvate and dimethylsulphoniopropionate, and Thalassobacter sp. M3‐A3 with pyruvate and amino acids). Furthermore, different carbon compounds triggered the development of unique combinations of dominant phylotypes in several of the experiments. These results suggest that bacteria differ substantially in their abilities to utilize specific carbon compounds, with some bacteria being specialists and others having a more generalist strategy. Thus, changes in the supply or composition of the dissolved organic carbon pool can act as selective forces structuring bacterioplankton communities.
Inhibition of Bacillus subtilis natural competence by a native, conjugative plasmid‐encoded comK repressor protein
Authors: Singh Praveen K. , Ramachandran Gayetri , Durán‐Alcalde Lucía , Alonso Carlos , Wu Ling Juan , Meijer Wilfried J. J.
Published: June 2012

Under certain growth conditions, Bacillus subtilis can develop natural competence, the state in which it is able to bind, adsorb and incorporate exogenous DNA. Development of competence is a bistable process and is subject to complex regulation. Rok is a repressor of the key transcriptional activator of competence genes, comK, and limits the size of the subpopulation that develops competence. Here we report the finding that the large conjugative B. subtilis plasmid pLS20 harbours a rok homologue rokLS20. Although the deduced product of rokLS20 is considerably shorter than the chromosomally encoded Rok protein, we show that ectopic expression of the plasmid‐encoded RokLS20 leads to inhibition of competence by repressing comK, and that the effects of the plasmid and chromosomally encoded Rok proteins are additive. We also show that pLS20 inhibits competence in a rokLS20‐dependent manner and that purified RokLS20 preferentially binds to the comK promoter. By analysing the available databases we identified several additional rok‐like genes. These putative rok genes can be divided into two groups and we propose that rokLS20 is the prototype of a newly identified subgroup of nine rok genes. Finally, we discuss the possible role of the plasmid‐located rok and its relatedness with other rok genes.
Hypolithic microbial communities: between a rock and a hard place
Authors: Chan Yuki , Lacap Donnabella C. , Lau Maggie C. Y. , Ha Kong Ying , Warren‐Rhodes Kimberley A. , Cockell Charles S. , Cowan Donald A. , McKay Christopher P. , Pointing Stephen B.
Published: June 2012

Drylands are the largest terrestrial biome on Earth and a ubiquitous feature is desert pavement terrain, comprising rocks embedded in the mineral soil surface. Quartz and other translucent rocks are common and microbial communities termed hypoliths develop as biofilms on their ventral surfaces. In extreme deserts these represent major concentrations of biomass, and are emerging as key to geobiological processes and soil stabilization. These highly specialized communities are dominated by cyanobacteria that support diverse heterotrophic assemblages. Here we identify global‐scale trends in the ecology of hypoliths that are strongly related to climate, particularly with regard to shifts in cyanobacterial assemblages. A synthesis of available data revealed a linear trend for colonization with regard to climate, and we suggest potential application for hypoliths as ‘biomarkers’ of aridity on a landscape scale. The potential to exploit the soil‐stabilizing properties of hypolithic colonization in environmental engineering on dryland soils is also discussed.
Staging lymphadenectomy in renal cell carcinoma must be extended: a sensitivity curve analysis
Authors: Capitanio Umberto , Suardi Nazareno , Matloob Rayan , Abdollah Firas , Castiglione Fabio , Briganti Alberto , Carenzi Cristina , Roscigno Marco , Montorsi Francesco , Bertini Roberto
Published: June 2012

What's known on the subject? and What does the study add?

In renal cell carcinoma the role of lymphadenectomy (LND) is still controversial. Moreover, no firm consensus exists regarding the minimum number of lymph nodes that should be removed to obtain a satisfactory staging LND at the time of surgery.

Our findings demonstrate that, when clinically indicated, staging LND in renal cell carcinoma should be extended. The removal of 15 lymph nodes might represent the lowest threshold to define a staging LND as adequate. More extended LND should be pursued if unfavourable clinical and pathological characteristics are evident at diagnosis and/or during surgery.

Objective

To investigate the staging of lymphadenectomy in renal cell carcinoma. No convincing data exist regarding the minimum number of lymph nodes that should be removed at the time of nephrectomy to ensure an accurate staging.

Methods

Between 1987 and 2011, 850 patients with renal cell carcinoma underwent either partial or radical nephrectomy plus lymph node dissection (LND) at a single tertiary care institution (TanyN0–1Many). Receiver operating characteristic curve coordinates were used to graph the probability of finding lymph node invasion according to the number of removed lymph nodes. Assuming that the likelihood of finding lymph node invasion according to the number of lymph nodes removed may be affected by patient characteristics, analyses were further stratified for clinical and pathological characteristics.

Results

The rate of lymph node metastases strongly correlated with the clinical and pathological characteristics of the patients. Fifteen lymph nodes need to be removed to achieve a 90% probability of detecting at least one metastatic lymph node. Only slight differences were recorded after stratification for clinical nodal status, the presence of metastases at diagnosis and pathological T stage. Finally, 13, 16 and 21 lymph nodes need to be removed to achieve a 90% probability of detecting lymph node invasion, if present, in the low risk (score 0–1), intermediate risk (score 2–3) and high risk (score 4–5) Mayo Clinic classification, respectively.

Conclusion

The removal of 15 lymph nodes represents the lowest threshold for considering a staging LND as adequate. More extended LND should be pursued if unfavourable clinical and pathological characteristics are evident at diagnosis and/or during surgery.
The development of reading skills in young partially sighted readers
Authors: Tobin Michael , Hill Eileen W.
Published: June 2012

Young learners with severe visual impairments are restricted in many ways, and psychologists and special needs teachers require information about the nature and extent of the possible educationally handicapping effects. This article, written by Michael Tobin, Emeritus Professor of Special Education within the School of Education at the University of Birmingham, and Eileen Hill, a teacher at Queen Alexandra College, Birmingham, reports the use of a longitudinal approach to measure how reading development is affected in these children and to uncover the relationships with and among other cognitive factors. The 60 participants were part of a larger cohort of children registered as blind or partially sighted, their reading progress being monitored from seven to 12 years of age. While improving in all three skill areas as measured by the Neale Analysis of Reading Ability, there were significant deficits/lags in development as compared with the norms for their fully‐sighted age peers, especially in speed of reading. Even more disturbing was the finding that the deficits increased with age. Significant correlates of reading, changing in importance over time, were intelligence, visual efficiency, phonological awareness, vocabulary knowledge and short‐term memory. It is proposed that, if the educationally handicapping effects of the impairment are to be overcome, a formal, regular cycle of testing to monitor progress be instituted by specialist teachers and educational psychologists. together with the design, development and standardisation of a new reading assessment procedure; and that the professionals collaborate in the construction of programmes of continuing structured teaching to improve speed of reading throughout primary and early secondary schooling.
RIVER DEEP
Authors: Crainer Stuart
Published: June 2012

Low‐profile and family‐owned, River Island is a retail surprise. Stuart Crainer taps into fashion consciousness with CEO Ben Lewis.
VITAL STATISTICS
Authors: Crainer Stuart
Published: June 2012

Numbers are the fuel which drives the London economy. They also shed light on the city's history and dynamically cosmopolitan present.
LONDON LIVING
Authors: Nicholson Nigel
Published: June 2012

Urban living is the modern reality. Nigel Nicholson provides a unique perspective on human nature out of nature.
THE PRICE OF OLYMPIC SUCCESS
Authors: Bertini Marco , Crainer Stuart
Published: June 2012

Pricing almost eight million tickets for the 2012 London Olympic Games was a hugely complex challenge. How could those in charge of the Olympics, billed as ‘Everybody's Games’, juggle the clashing objectives of the event's many stakeholders?Marco Bertini spoke with Stuart Crainer about the challenge of Olympic ticketing and what it reveals about setting the price of all goods in the future, especially given today's savvy consumers and the new technologies that are changing the way business is done.
BRITISH ENTREPRENEURS, GLOBAL VISIONS
Authors: Meyer Klaus , Xia Helen
Published: June 2012

Start‐ups used to start local and then expand globally. Now, say Klaus Meyer and Helen Xia, a growing number start local and global.
THE NEW OIL
Authors: Crainer Stuart
Published: June 2012

The British social philosopher Charles Handy celebrates his 80th birthday in 2012. His work provides a powerful link between the leading pioneers of management thinking and the future of work. Ideas really are the new oil. Stuart Crainer examines Handy's unique contribution.
BANK ON IT
Authors: Ball Ray , Jayaraman Sudarshan , Shivakumar Lakshmanan
Published: June 2012

Ray Ball, Sudarshan Jayaraman and Lakshmanan Shivakumar, “Audited financial reporting and voluntary disclosure as complements: A test of the confirmation hypothesis”, Journal of Accounting and Economics, 2011 (http://dx.doi.org/10.1016/j.jacceco.2011.11.005).
VOICES: SEARCHING FOR THE TRUE LEADER
Authors: Sorich David W
Published: June 2012

What are the essential components of being a good leader?David W Sorich tells of his quest to find the most fundamental qualities.
Earning While Learning: When and How Student Employment is Beneficial
Authors: Geel Regula , Backes‐Gellner Uschi
Published: June 2012

Although studies of student employment (‘earning while learning’) mostly find positive wage effects, they do not adequately consider the relation of the employment to the field of study. We investigate how different types of student employment during tertiary education affect short‐ and long‐term labour market returns. Beyond examining differences between non‐working and part‐time working students, we distinguish between student employment related and unrelated to the field of study. Our results show significant positive labour market returns of ‘earning while learning’ only for student employment related to the field of study. These returns consist of a lower unemployment risk, shorter job‐search duration, higher wage effects, and greater job responsibility.
Product Market Regulation and Labor Market Performance around the World
Authors: Feldmann Horst
Published: June 2012

Using annual data on 80 countries for 1980–2007 and a new indicator of product market regulation, this paper studies the effects of product market regulation on labor market performance among the total population as well as among two important groups of labor market outsiders: women and youth. It finds that stricter regulation is likely to both increase the unemployment rate and decrease the employment rate. The magnitude of the estimated effects is substantial. There are above‐average effects on both groups of outsiders, with the effects being particularly strong on youth. The results are robust to variations in specification.