bluuebunny/crossref_metadata_2025 huggingface dataset:
Bld10/Cep135 stabilizes basal bodies to resist cilia-generated forces
Authors: Bayless Brian A. , Giddings Thomas H. , Winey Mark , Pearson Chad G.
Published: November 2012

Basal bodies nucleate, anchor, and organize cilia. As the anchor for motile cilia, basal bodies must be resistant to the forces directed toward the cell as a consequence of ciliary beating. The molecules and generalized mechanisms that contribute to the maintenance of basal bodies remain to be discovered. Bld10/Cep135 is a basal body outer cartwheel domain protein that has established roles in the assembly of nascent basal bodies. We find that Bld10 protein first incorporates stably at basal bodies early during new assembly. Bld10 protein continues to accumulate at basal bodies after assembly, and we hypothesize that the full complement of Bld10 is required to stabilize basal bodies. We identify a novel mechanism for Bld10/Cep135 in basal body maintenance so that basal bodies can withstand the forces produced by motile cilia. Bld10 stabilizes basal bodies by promoting the stability of the A- and C-tubules of the basal body triplet microtubules and by properly positioning the triplet microtubule blades. The forces generated by ciliary beating promote basal body disassembly in bld10Δ cells. Thus Bld10/Cep135 acts to maintain the structural integrity of basal bodies against the forces of ciliary beating in addition to its separable role in basal body assembly.
Brr2p-mediated conformational rearrangements in the spliceosome during activation and substrate repositioning
Authors: Hahn Daniela , Kudla Grzegorz , Tollervey David , Beggs Jean D.
Published: November 2012

Brr2p is one of eight RNA helicases involved in pre-mRNA splicing. Detailed understanding of the functions of Brr2p and other spliceosomal helicases has been limited by lack of knowledge of their in vivo substrates. To address this, sites of direct Brr2p–RNA interaction were identified by in vivo UV cross-linking in budding yeast. Cross-links identified in the U4 and U6 small nuclear RNAs (snRNAs) suggest U4/U6 stem I as a Brr2p substrate during spliceosome activation. Further Brr2p cross-links were identified in loop 1 of the U5 snRNA and near splice sites and 3′ ends of introns, suggesting the possibility of a previously uncharacterized function for Brr2p in the catalytic center of the spliceosome. Consistent with this, mutant brr2-G858R reduced second-step splicing efficiency and enhanced cross-linking to 3′ ends of introns. Furthermore, RNA sequencing indicated preferential inhibition of splicing of introns with structured 3′ ends. The Brr2-G858Rp cross-linking pattern in U6 was consistent with an open conformation for the catalytic center of the spliceosome during first-to-second-step transition. We propose a previously unsuspected function for Brr2p in driving conformational rearrangements that lead to competence for the second step of splicing.
Metabolic compensation of the Neurospora clock by a glucose-dependent feedback of the circadian repressor CSP1 on the core oscillator
Authors: Sancar Gencer , Sancar Cigdem , Brunner Michael
Published: November 2012

Conidial separation 1 (CSP1) is a global transcription repressor. It is expressed under control of the white collar complex (WCC), the core transcription factor of the circadian clock of Neurospora. Here we report that the length of the circadian period decreases with increasing glucose concentrations in csp1 mutant strains, while the period is compensated for changes in glucose concentration in wild-type strains. Glucose stimulated CSP1 expression. Overexpression of CSP1 caused period lengthening and, eventually, complete dampening of the clock rhythm. We show that CSP1 inhibits expression of the WHITE COLLAR 1 (WC1) subunit of the WCC by repressing the wc1 promoter. Glucose-dependent repression of wc1 transcription by CSP1 compensated for the enhanced translation of WC1 at high glucose levels, resulting in glucose-independent expression of the WCC and, hence, metabolic compensation that maintained a constant circadian period. Thus, the negative feedback of CSP1 on WC1 expression constitutes a molecular pathway that coordinates energy metabolism and the circadian clock.
Essential role for Notch signaling in restricting developmental plasticity
Authors: Djabrayan Nareg J.-V. , Dudley Nathaniel R. , Sommermann Erica M. , Rothman Joel H.
Published: November 2012

We report that Notch signaling is essential for the switch from developmental plasticity to commitment during Caenorhabditis elegans embryogenesis. The GLP-1 and LIN-12 Notch receptors act to set a memory state that affects commitment of cells arising from the major ectodermal progenitor (AB blastomere) several cell divisions later, thereby preventing their forced reprogramming by an endoderm-determining transcription factor. In contrast to Notch-dependent cell fate induction, this activity is autonomous to the AB lineage, is independent of the known cell fate-inducing Notch ligands, and requires a putative secreted Notch ligand, Delta Serrate Lag-3 (DSL-3). Thus, Notch signaling promotes developmental commitment by a mechanism that is distinct from that involved in specifying cell fates.
Data Analysis Considerations for Detecting Copy Number Changes in Formalin-Fixed, Paraffin-Embedded Tissues
Authors: Jacobs Sharoni
Published: November 2012

The Whole Genome Sampling Analysis (WGSA) assay in combination with Affymetrix GeneChip Mapping Arrays is used for copy number analysis of high-quality DNA samples (i.e., samples that have been collected from blood, fresh or frozen tissue, or cell lines). Formalin-fixed, paraffin-embedded (FFPE) samples, however, represent the most prevalent form of archived clinical samples, but they provide additional challenges for molecular assays. FFPE processing usually results in the degradation of FFPE DNA and in the contamination and chemical modification of these DNA samples. In this article, we describe the steps needed to obtain reliable copy number predictions from degraded and contaminated FFPE samples.
Objective-Type Total Internal Reflection Microscopy (Emission) for Single-Molecule FRET
Authors: Joo Chirlmin , Ha Taekjip
Published: November 2012

Single-molecule (sm) fluorescence detection is a powerful method for studying biological events without time and population averaging. Förster (fluorescence) resonance energy transfer (FRET) is a spectroscopic technique in which the efficiency of energy transfer from donor to acceptor molecules is used to determine distances between molecules in the 30–80 Å range. Structural changes in biological molecules or relative motion between two interacting molecules can be detected by a change in FRET. A variant of smFRET is based on total internal reflection (TIR) microscopy, which can be set up in two ways, either using an oil-immersion (objective-type) or a water-immersion (prism-type) lens. This protocol describes the preparation of a fluorescent bead sample and the setup for objective-type TIR microscopy (emission).
In Vivo Imaging of the Developing Neuromuscular Junction in Neonatal Mice
Authors: Turney Stephen G. , Walsh Mark K. , Lichtman Jeff W.
Published: November 2012

Although fluorescently labeled structures can be analyzed more easily at high resolution in fixed-tissue preparations than in living animals, some biological questions can only be answered by time-lapse imaging. Changes in nervous system wiring during development cannot be determined reliably by taking tissue from different animals at staggered time points. Rather, the same cells and connections must be viewed repeatedly. To study developmental synapse elimination, we image muscles in transgenic mice that express fluorescent proteins in motor neurons and follow the same neuromuscular junctions (NMJs) over multiple days. This protocol describes the use of confocal microscopy for in vivo imaging of developing NMJs in transgenic neonatal mice expressing cyan fluorescent protein (CFP) or yellow fluorescent protein (YFP). The sternomastoid, a flat, accessible neck muscle with large junctions, is imaged. A principal advantage of confocal microscopy is the ability to acquire multiple fluorescence channels simultaneously. If the channels are acquired sequentially, there is inevitably misalignment because of movement. Moreover, the total imaging time scales linearly with the number of channels. With simultaneous acquisition, only a single scan may be required. With perfect alignment between channels, irrespective of movement that might occur during a scan, color differences can be used to study interactions between axons over time. A limitation of this technique is that axons must be brightly labeled and at the muscle surface. NMJs that are more than one muscle fiber deep may be difficult to scan because of index of refraction changes that cause image blurring.
Tnt1 Retrotransposon Mutagenesis: A Tool for Soybean Functional Genomics
Authors: Cui Yaya , Barampuram Shyam , Stacey Minviluz G. , Hancock C. Nathan , Findley Seth , Mathieu Melanie , Zhang Zhanyuan , Parrott Wayne A. , Stacey Gary
Published: November 2012

Insertional mutagenesis is a powerful tool for determining gene function in both model and crop plant species. Tnt1, the transposable element of tobacco (Nicotiana tabacum) cell type 1, is a retrotransposon that replicates via an RNA copy that is reverse transcribed and integrated elsewhere in the plant genome. Based on studies in a variety of plants, Tnt1 appears to be inactive in normal plant tissue but can be reactivated by tissue culture. Our goal was to evaluate the utility of the Tnt1 retrotransposon as a mutagenesis strategy in soybean (Glycine max). Experiments showed that the Tnt1 element was stably transformed into soybean plants by Agrobacterium tumefaciens-mediated transformation. Twenty-seven independent transgenic lines carrying Tnt1 insertions were generated. Southern-blot analysis revealed that the copy number of transposed Tnt1 elements ranged from four to 19 insertions, with an average of approximately eight copies per line. These insertions showed Mendelian segregation and did not transpose under normal growth conditions. Analysis of 99 Tnt1 flanking sequences revealed insertions into 62 (62%) annotated genes, indicating that the element preferentially inserts into protein-coding regions. Tnt1 insertions were found in all 20 soybean chromosomes, indicating that Tnt1 transposed throughout the soybean genome. Furthermore, fluorescence in situ hybridization experiments validated that Tnt1 inserted into multiple chromosomes. Passage of transgenic lines through two different tissue culture treatments resulted in Tnt1 transposition, significantly increasing the number of insertions per line. Thus, our data demonstrate the Tnt1 retrotransposon to be a powerful system that can be used for effective large-scale insertional mutagenesis in soybean.
Competition for inorganic carbon between oxygenic and anoxygenic phototrophs in a hypersaline microbial mat, Guerrero Negro, Mexico
Authors: Finke Niko , Hoehler Tori M. , Polerecky Lubos , Buehring Benjamin , Thamdrup Bo
Published: November 2012

While most oxygenic phototrophs harvest light only in the visible range (400–700 nm, VIS), anoxygenic phototrophs can harvest near infrared light (> 700 nm, NIR). To study interactions between the photosynthetic guilds we used microsensors to measure oxygen and gross oxygenic photosynthesis (gOP) in a hypersaline microbial mat under full (VIS + NIR) and VIS illumination. Under normal dissolved inorganic carbon (DIC) concentrations (2 mM), volumetric rates of gOP were reduced up to 65% and areal rates by 16–31% at full compared with VIS illumination. This effect was enhanced (reduction up to 100% in volumetric, 50% in areal rates of gOP) when DIC was lowered to 1 mM, but diminished at 10 mM DIC or lowered pH. In conclusion, under full‐light illumination anoxygenic phototrophs are able to reduce the activity of oxygenic phototrophs by efficiently competing for inorganic carbon within the highly oxygenated layer. Anoxygenic photosynthesis, calculated from the difference in gOP under full and VIS illumination, represented between 10% and 40% of the C‐fixation. The DIC depletion in the euphotic zone as well as the significant C‐fixation by anoxygenic phototrophs in the oxic layer influences the carbon isotopic composition of the mat, which needs to be taken into account when interpreting isotopic biosignals in geological records.
How the impact of HR practices on employee well‐being and performance changes with age
Authors: Kooij Dorien T.A.M. , Guest David E. , Clinton Mike , Knight Terry , Jansen Paul G.W. , Dikkers Josje S.E.
Published: November 2012

With changing retirement ages and an aging workforce, interest is growing on the potential contribution of relevant bundles of HR practices in eliciting well‐being and performance among aging workers. Drawing on theories on lifespan development and self‐regulation, we distinguished two bundles of HR practices: development HR practices that help individual workers reach higher levels of functioning (e.g. training), and maintenance HR practices that help individual workers maintain their current levels of functioning in the face of new challenges (e.g. performance appraisal). Further, based on lifespan theories, we expected and found that the association between development HR practices and well‐being (i.e. job satisfaction, organisational commitment and organisational fairness) weakens, and that the associations between maintenance HR practices and well‐being, and between development HR practices and employee performance, strengthen with age. In addition, a third bundle of ‘job enrichment’ HR practices emerged that elicited higher job performance among aging workers.
Postpartum infections: occurrence, healthcare contacts and association with breastfeeding
Authors: AHNFELDT‐MOLLERUP PEDER , PETERSEN LINE KIRKEBY , KRAGSTRUP JAKOB , CHRISTENSEN RENÉ DEPONT , SØRENSEN BENTE
Published: November 2012

Objective. To investigate the following: (i) the occurrence of postpartum infections; (ii) the frequency of contact with either a general practitioner or a hospital due to postpartum infections; and (iii) the association of postpartum infections with continuation of breastfeeding. Design. Cross‐sectional study. Setting. Department of Gynecology and Obstetrics Horsens Hospital, Horsens, Denmark. Population. A total of 1871 women who gave birth at a regional hospital in Denmark over a one‐year period (2007–2008). Methods. Data were collected by a questionnaire given to the women and combined with data from general practitioner and hospital records. Main outcome measures. The distribution of different infections, as well as the overall occurrence of any infection, was evaluated according to mode of delivery and breastfeeding status (stopped/continued). Results. Within four weeks after delivery, 24% of all women had experienced one or more self‐reported episode of infection. Breast infections (12%) were most frequent, followed by wound (3%), airway (3%), vaginal (3%) and urinary tract infections (3%), endometritis (2%) and “other infections” (2%). Of the women with an infection, 66% (265 of 395) contacted their general practitioner, while 9% (37 of 395) had contact with a hospital. A significantly larger proportion of women with a postpartum infection stopped breastfeeding (21%) within the first four weeks after delivery compared with women without infection (12%; p < 0.001). Conclusions. Postpartum infections were common, and the occurrence is likely to be underestimated if based on hospital medical records only. Infection was associated with higher rates of discontinuation of breastfeeding.
Clinical characteristics of eosinophilic and noneosinophilic asthma in children
Authors: Lee Yong Ju , Kim Kyung Won , Choi Bong Seok , Sohn Myung Hyun , Kim Kyu‐Earn
Published: November 2012

Aim

Asthma is a heterogeneous and complex chronic inflammatory disease of the airways. Asthma can be classified as eosinophilic asthma (EA) or noneosinophilic asthma (NEA). We investigated whether children with EA manifest different clinical characteristics than those with NEA.

Methods

We enrolled 288 steroid‐naive asthmatic children and classified them, based on the cell counts in induced sputum, into EA (158 children) and NEA (89 children) groups.

Results

No significant differences were observed between the groups with regard to age, sex, family history of atopy, secondary smoking or asthma exacerbations. Moderate‐to‐severe asthma was more frequent in the EA group than in the NEA group. Blood eosinophil counts and serum eosinophil cationic protein were higher in EA patients than in NEA patients. The forced expiratory volume in 1 sec was lower in children with EA than in those with NEA (% of predicted value, 88.6 ± 18.5 vs. 93.6 ± 15.6, p < 0.05). The sputum eosinophil (in EA) and neutrophil (in NEA) counts increased with increasing asthma severity.

Conclusion

Airway inflammation, especially eosinophilic inflammation, was associated with asthma severity and reduced pulmonary function in children.
Use of systemic glucocorticoids and the risk of colorectal cancer
Authors: Ostenfeld E. B. , Erichsen R. , Thorlacius‐Ussing O. , Riis A. H. , Sørensen H. T.
Published: November 2012

Background

Systemic glucocorticoids are potent immunosuppressants, potentially facilitating carcinogenesis. Studies examining glucocorticoids and colorectal cancer risk are few.

Aim

To investigate the association between use of systemic glucocorticoids and colorectal cancer risk, both overall and by cancer stage (localised versus metastatic).

Methods

We conducted a nested population‐based case–control study in Northern Denmark (1.8 million people) using medical registries. The study included 14 158 patients with a first‐time diagnosis of colorectal cancer from 1991 through 2010. Using risk set sampling, we identified 141 580 population controls, matched on age and gender. Logistic regression models were used to compute odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for covariates.

Results

Frequent use of systemic glucocorticoids (defined as >2 prescriptions) was not associated with overall colorectal cancer risk [adjusted OR (aOR) = 0.93 (95% CI: 0.85–1.00)], compared with never/rare use (≤2 prescriptions). Associations according to duration of use and doses (quartiles of cumulative prednisolone equivalents) were also near the null. Examining colorectal cancer by stage, no substantial associations were found between long‐term use (>5 years) of high‐dose (>5500 mg) systemic glucocorticoids and localised [aOR = 1.12 (95% CI: 0.81–1.55)] or metastatic [aOR = 0.82 (95% CI: 0.59–1.14)] cancer.

Conclusion

Despite immunological and metabolic effects of frequent use of systemic glucocorticoids, which would be expected to increase colorectal cancer risk, we found no substantial association between the two.
Early stage development of the glycine‐1 re‐uptake inhibitor SCH 900435: central nervous system effects compared with placebo in healthy men
Authors: Liem‐Moolenaar Marieke , Peeters Pierre , Kamerling Ingrid M. C. , Hogg Chris , Holder Graham , Kleijn Huub Jan , Spaans Edwin , Udo De Haes Joanna , de Kam Marieke L. , Franson Kari L. , Cohen Adam F. , van Gerven Joop M. A.
Published: November 2012

Aims

To report the first three studies with SCH 900435, a selective glycine‐1 re‐uptake inhibitor in development for treating schizophrenia, using systematic evaluations of pharmacodynamics to understand the observed effects.

Methods

Three double‐blind, placebo‐controlled studies (single, visual effect and multiple dose) were performed. In the single and multiple dose study SCH 900435 (0.5–30 mg) was given to healthy males and frequent pharmacokinetic and pharmacodynamic measurements were performed. The visual effects study incorporated visual electrophysiological measures of macular, retinal and intracranial visual pathway function.

Results

In the single dose study (highest difference, 95% CI, P) increases in smooth pursuit eye movements (8, 12 mg (−6.09, 10.14, −2.04, 0.013), 30 mg), pupil : iris ratio (20 and 30 mg (−0.065, 0.09, −0.04, <0.0001)), VAS colour perception (30 mg (−9.48, 13.05, −5.91, <0.0001)) and changes in spontaneous reports of visual disturbance were found, while FSH (8 mg (0.42, 0.18, 0.66, 0.0015), 12, 20 mg), LH (8–30 mg (1.35, 0.65, 2.05, 0.0003)) and EEG alpha2 activity decreased (12, 20, 30 mg (0.27, 0.14, 0.41, 0.0002)). A subsequent dedicated visual effects study demonstrated that visual effects were transient without underlying electrophysiological changes. This provided enough safety information for starting a multiple ascending dose study, showing less visual symptoms after twice daily dosing and titration, possibly due to tolerance.

Conclusions

Several central nervous system (CNS) effects and gonadotropic changes resulted from administration of 8 mg and higher, providing evidence for CNS penetration and pharmacological activity of SCH 900435. Antipsychotic activity in patients, specificity of the reported effects for this drug class and possible tolerance to visual symptoms remain to be established.
A comparison of 4β‐hydroxycholesterol : cholesterol and 6β‐hydroxycortisol : cortisol as markers of CYP3A4 induction
Authors: Mårde Arrhén Yvonne , Nylén Hanna , Lövgren‐Sandblom Anita , Kanebratt Kajsa P. , Wide Katarina , Diczfalusy Ulf
Published: November 2012

Aim

To compare plasma 4β‐hydroxycholesterol : cholesterol with urinary 6β‐hydroxycortisol : cortisol as markers of cytochrome P4503A4 activity before and after treatment with rifampicin for 2 weeks.

Method

6β‐hydroxycortisol and cortisol were determined by liquid chromatography tandem mass spectrometry and 4β‐hydroxycholesterol was determined by gas chromatography–mass spectrometry in three groups of healthy volunteers.

Results

Induction ratios for 6β‐hydroxycortisol : cortisol were 1.8, 3.9 and 4.5 for 20 mg day−1, 100 mg day−1 or 500 mg day−1 of rifampicin, respectively. The corresponding ratios for 4β‐hydroxycholesterol : cholesterol were 1.5, 2.4 and 3.8.

Conclusions

Plasma 4β‐hydroxycholesterol : cholesterol gave similar induction ratios to urinary 6β‐hydroxycortisol : cortisol.
A randomized phase I study of methanesulfonyl fluoride, an irreversible cholinesterase inhibitor, for the treatment of Alzheimer's disease
Authors: Moss Donald E. , Fariello Ruggero G. , Sahlmann Jörg , Sumaya Isabel , Pericle Federica , Braglia Enrico
Published: November 2012

Aims

To ascertain the tolerability profile of single and repeated oral doses of methanesulfonyl fluoride (MSF, SNX‐001) in healthy aged subjects, and to determine the degree of erythrocyte acetylcholinesterase (AChE) inhibition induced by MSF after single and repeated oral doses.

Methods

To calculate properly the kinetics and the duration of AChE inhibition, the effects of MSF were also studied in rodents. These experiments suggested that MSF administered three times per week should provide safe and efficacious AChE inhibition. In a randomized placebo‐controlled phase I study, 3.6 mg, 7.2 mg or 10.8 mg MSF were then orally administered to 27 consenting healthy volunteers (aged 50 to 72 years). After a single dose phase and a 1 week wash‐out period, the subjects received the same doses three times per week for 2 weeks.

Results

Twenty‐two out of the 27 subjects completed the study. Four patients withdrew due to adverse events (AEs) and one for non‐compliance. Erythrocyte AChE was inhibited by a total of 33%, 46%, and 62% after 2 weeks of 3.6 mg, 7.2 mg and 10.8 mg MSF, respectively. No serious AEs occurred. The most frequent AEs were headache (27%), nausea (11%) and diarrhoea (8%).

Conclusions

MSF proved to be well tolerated even with repeated oral dosing. It is estimated that MSF provided a degree of AChE inhibition that should effectively enhance memory. This molecule deserves to be tested for efficacy in a pilot randomized controlled study in patients with Alzheimer's disease.
Characterization of AQX‐1125, a small‐molecule SHIP1 activator
Authors: Stenton Grant R , Mackenzie Lloyd F , Tam Patrick , Cross Jennifer L , Harwig Curtis , Raymond Jeffrey , Toews Judy , Wu Joyce , Ogden Nancy , MacRury Thomas , Szabo Csaba
Published: November 2012

Background

The SH2‐containing inositol‐5′‐phosphatase 1 (SHIP1) metabolizes PI(3,4,5)P3 to PI(3,4)P2. SHIP1‐deficient mice exhibit progressive inflammation. Pharmacological activation of SHIP1 is emerging as a potential therapy for pulmonary inflammatory diseases. Here we characterize the efficacy of AQX‐1125, a small‐molecule SHIP1 activator currently in clinical development.

Experimental Approach

The effects of AQX‐1125 were tested in several in vitro assays: on enzyme catalytic activity utilizing recombinant human SHIP1, on Akt phosphorylation in SHIP1‐proficient and SHIP1‐deficient cell lines, on cytokine release in murine splenocytes, on human leukocyte chemotaxis using modified Boyden chambers and on β‐hexosaminidase release from murine mast cells. In addition, pharmacokinetic and drug distribution studies were performed in rats and dogs.

Results

AQX‐1125 increased the catalytic activity of human recombinant SHIP1, an effect, which was absent after deletion of the C2 region. AQX‐1125 inhibited Akt phosphorylation in SHIP1‐proficient but not in SHIP1‐deficient cells, reduced cytokine production in splenocytes, inhibited the activation of mast cells and inhibited human leukocyte chemotaxis. In vivo, AQX‐1125 exhibited >80% oral bioavailability and >5 h terminal half‐life.

Conclusions

Consistent with the role of SHIP1 in cell activation and chemotaxis, the SHIP1 activator AQX‐1125 inhibits Akt phosphorylation, inflammatory mediator production and leukocyte chemotaxis in vitro. The in vitro effects and the pharmacokinetic properties of the compound make it a suitable candidate for in vivo testing in various models of inflammation.

Linked Article

This article is accompanied by Stenton et al., pp. 1519–1529 of this issue. To view this article visit http://dx.doi.org/10.1111/bph.12038
Inhibition of CXCR3‐mediated chemotaxis by the human chemokine receptor‐like protein CCX‐CKR
Authors: Vinet J , van Zwam M , Dijkstra IM , Brouwer N , van Weering HRJ , Watts A , Meijer M , Fokkens MR , Kannan V , Verzijl D , Vischer HF , Smit MJ , Leurs R , Biber K , Boddeke HWGM
Published: November 2012

Background and Purpose

Induction of cellular migration is the primary effect of chemokine receptor activation. However, several chemokine receptor‐like proteins bind chemokines without subsequent induction of intracellular signalling and chemotaxis. It has been suggested that they act as chemokine scavengers, which may control local chemokine levels and contribute to the function of chemokines during inflammation. This has been verified for the chemokine‐like receptor proteins D6 and DARC as well as CCX‐CKR. Here, we provide evidence for an additional biological function of human (h)CCX‐CKR.

Experimental Approach

We used transfection strategies in HEK293 and human T cells.

Key Results

Co‐expression of hCCX‐CKR completely inhibits hCXCR3‐induced chemotaxis. We found that hCCX‐CKR forms complexes with hCXCR3, suggesting a relationship between CCX‐CKR heteromerization and inhibition of chemotaxis. Moreover, negative binding cooperativity induced by ligands both for hCXCR3 and hCCX‐CKR was observed in cells expressing both receptors. This negative cooperativity may also explain the hCCX‐CKR‐induced inhibition of chemotaxis.

Conclusions and Implications

These findings suggest that hCCX‐CKR prevents hCXCR3‐induced chemotaxis by heteromerization thus representing a novel mechanism of regulation of immune cell migration.
Thymic stromal lymphopoietin expression is increased in the horny layer of patients with atopic dermatitis
Authors: Sano Y , Masuda K , Tamagawa-Mineoka R , Matsunaka H , Murakami Y , Yamashita R , Morita E , Katoh N
Published: November 2012

Thymic stromal lymphopoietin (TSLP) is known for its capacity to induce CD11c+ myeloid dendritic cells to promote T helper type 2 (Th2)-skewed inflammatory responses. Although increased expression of TSLP was reported in the lesional skin of limited numbers of patients with atopic dermatitis (AD), the relationships between the degree of TSLP expression in the skin and the severity of AD, epidermal barrier function and eruption type remain to be elucidated. The aim of this study was to examine the relationships between the degree of TSLP expression in the skin and the severity of AD, eruption type and epidermal barrier function using a non-invasive method in a sizeable group of the patients. Stratum corneum tissue was obtained from AD patients by tape stripping, and the stratum corneum TSLP (scTSLP) expression level was evaluated using a TSLP-specific antibody followed by image analysis. The correlations between the scTSLP intensity and the severity scoring of AD (SCORAD) index and epidermal barrier function, such as stratum corneum hydration and transepidermal water loss (TEWL), were analysed. The changes in the scTSLP level induced by the application of moisturizer were also examined. The scTSLP expression level was increased in AD patients compared with healthy subjects and was correlated with SCORAD, especially with the dry skin score, and stratum corneum hydration. Moisturizer application resulted in reduced scTSLP levels. The scTSLP level can be used as a biomarker of AD severity and particularly epidermal barrier status.
The prognostic accuracy of resonance frequency analysis in predicting failure risk of immediately restored implants
Authors: Atieh Momen A. , Alsabeeha Nabeel H. M. , Payne Alan G. T. , de Silva Rohana K. , Schwass Donald S. , Duncan Warwick J.
Published: November 2012

Objectives

It is of imperative clinical significance to define a safe threshold for planned immediate implant restoration. The aim of this report was to evaluate the prognostic accuracy of resonance frequency analysis (RFA) measurements recorded at two different times (implant placement and 8‐week post‐implant placement) and to determine the optimal threshold value for predicting failure risk of immediately restored/loaded implants.

Material and methods

Twenty‐eight 8‐ or 9‐mm‐diameter implants were placed in either a fresh molar extraction socket or a healed site. An electronic RFA device was used to record the implant stability quotients (ISQs) at implant placement surgery, 8 weeks and 1 year. Receiver operating characteristic (ROC) analysis was used to identify the optimal cut‐off level. Sensitivity and specificity were also determined at the selected cut‐off value.

Results

The area under the ROC curve for RFA at 8 weeks was 0.93 with a significant P‐value (P = 0.001). The optimum cut‐off value for detecting implant stability was 60.5 ISQ measured at 8 weeks, with sensitivity and specificity of 95.2% and 71.4%, respectively.

Conclusions

The implant stability measurements after 8 weeks showed a better accuracy in predicting implants that were at risk of failure than those taken at the time of implant placement.
A Test of the Testing Effect: Acquiring Problem‐Solving Skills From Worked Examples
Authors: van Gog Tamara , Kester Liesbeth
Published: November 2012

The “testing effect” refers to the finding that after an initial study opportunity, testing is more effective for long‐term retention than restudying. The testing effect seems robust and is a finding from the field of cognitive science that has important implications for education. However, it is unclear whether this effect also applies to the acquisition of problem‐solving skills, which is important to establish given the key role problem solving plays in, for instance, math and science education. Worked examples are an effective and efficient way of acquiring problem‐solving skills. Forty students either only studied worked examples (SSSS) or engaged in testing after studying an example by solving an isomorphic problem (STST). Surprisingly, results showed equal performance in both conditions on an immediate retention test after 5 min, but the SSSS condition outperformed the STST condition on a delayed retention test after 1 week. These findings suggest the testing effect might not apply to acquiring problem‐solving skills from worked examples.
The Influence of the Brain‐Derived Neurotropic Factor Val66Met ‐Genotype and HMG‐CoA Reductase Inhibitors on Insulin Resistance in the Schizophrenia and Bipolar Populations
Authors: Burghardt K.J. , Pop‐Busui R. , Bly M.J. , Grove T.B. , Taylor S.F. , Ellingrod V.L.
Published: November 2012

Introduction: The brain‐derived neurotrophic factor (BDNF) Val66Met variant and HMG‐COA reductase inhibitors (statins) have been implicated in insulin resistance with a possible increased risk of diabetes. We sought to determine the effect of the BDNF Met variant and statin medication use on insulin resistance in schizophrenia and bipolar disorder using the homeostasis model assessment of insulin resistance (HOMA‐IR).

Methods: A cross‐sectional design was used and patients with diabetes or on any medications affecting glucose regulation were ‐excluded. Associations between insulin resistance and genotype were then analyzed by ANOVA and regression analysis. Subjects were grouped by BDNF genotype as well as presence of statin.

Results: Two hundred fifty‐two subjects with a mean age of 44 years were included. The group was 53% male and 41% had a diagnosis of bipolar disorder; 78% and 19% were receiving atypical antipsychotics (AAPs) and statin medications, respectively. Analysis showed schizophrenia subjects with the BDNF met allele as well as schizophrenia subjects with both the BDNF met allele and were receiving a statin had significantly higher HOMA‐IR values compared to the other groups (p= 0.046 and p= 0.016, respectively).

Conclusions: Our results suggest that in the metabolically high‐risk population of schizophrenia the BDNF met allele alone and in combination with statin medications is associated with higher insulin resistance values. This was not seen in the bipolar population. Further validation of these associations remains necessary. Clin Trans Sci 2012; Volume 5: 486–490
Australian university students' attitudes towards the use of prescription stimulants as cognitive enhancers: Perceived patterns of use, efficacy and safety
Authors: Partridge Brad , Bell Stephanie , Lucke Jayne , Hall Wayne
Published: November 2012

Introduction and Aims

Recent, high profile articles in leading science journals have claimed that the enhancement use of prescription stimulants is a common practice among students worldwide. This study provides empirical data on Australian university students' perceptions of: (i) the prevalence of prescription stimulant use by their peers for cognitive enhancement; (ii) motivations for such use; (iii) efficacy; and (iv) its safety.

Design and Methods

Participants were 19 Australian university students with an average age of 24 who were recruited through emails lists, notice board posters and snowball sampling. Semi‐structured interviews were conducted during 2010 and 2011, recordings transcribed and responses coded using thematic analysis.

Results

Participants typically did not believe the use of stimulants for cognitive enhancement was common in Australia. Perceived motivations for use included: (i) ‘getting ahead’ to perform at high levels; (ii) ‘keeping up’ as a method of coping; and (iii) ‘going out’ so that an active social life could be maintained in the face of study demands. Australian students were generally sceptical about the potential benefits of stimulants for cognitive enhancement and they identified psychological dependence as a potential negative consequence.

Discussion and Conclusions

This study is an important first step in understanding the use of stimulants for cognitive enhancement in Australia, amid calls for more widespread use of cognitive enhancing drugs. It is important to conduct further studies of the extent of cognitive enhancement in Australia if we are to develop appropriate policy responses.
When less is more: the forbidden fruits of gene repression in the adult β‐cell
Authors: Pullen T. J. , Rutter G. A.
Published: November 2012

Outside of the biological arena the term ‘repression’ often has a negative connotation. However, in the pancreatic β‐cell a small group of genes, which are abundantly expressed in most if not all other mammalian tissues, are highly selectively repressed, with likely functional consequences. The two ‘founder’ members of this group, lactate dehydrogenase A (Ldha) and monocarboxylate transporter‐1 (MCT‐1/Slc16a1), are inactivated by multiple mechanisms including histone modifications and microRNA‐mediated silencing. Their inactivation ensures that pyruvate and lactate, derived from muscle during exercise, do not stimulate insulin release inappropriately. Correspondingly, activating mutations in the MCT‐1 promoter underlie ‘exercise‐induced hyperinsulinism’ (EIHI) in man, a condition mimicked by forced over‐expression of MCT‐1 in the β‐cell in mice. Furthermore, LDHA expression in the β‐cell is upregulated in both human type 2 diabetes and in rodent models of the disease. Recent work by us and by others has identified a further ∼60 genes which are selectively inactivated in the β‐cell, a list which we refine here up to seven by detailed comparison of the two studies. These genes include key regulators of cell proliferation and stimulus‐secretion coupling. The present, and our earlier results, thus highlight the probable importance of shutting down a subset of ‘disallowed’ genes for the differentiated function of β‐cells, and implicate previously unsuspected signalling pathways in the control of β‐cell expansion and insulin secretion. Targeting of deregulated ‘disallowed’ genes in these cells may thus, in the future, provide new therapeutic avenues for type 2 diabetes.
Hypoglycaemia and accident risk in people with type 2 diabetes mellitus treated with non‐insulin antidiabetes drugs
Authors: Signorovitch J. E. , Macaulay D. , Diener M. , Yan Y. , Wu E. Q. , Gruenberger J.‐B. , Frier B. M.
Published: November 2012

Aims

To assess associations between hypoglycaemia and risk of accidents resulting in hospital visits among people with type 2 diabetes receiving antidiabetes drugs without insulin.

Methods

People with type 2 diabetes who were not treated with insulin were identified from a US‐based employer claims database (1998–2010). Following initiation of an antidiabetes drug, the occurrence of accidents resulting in hospital visits was compared between people with, and without, claims for hypoglycaemia using multivariable Cox proportional hazard models adjusted for demographics, comorbidities, prior treatments and prior medical service use. Additional analyses were stratified by age 65 years or older.

Results

A total of N = 5582 people with claims for hypoglycaemia and N = 27 910 with no such claims were included. Accidents resulting in hospital visits occurred in 5.5 and 2.8% of people with, and without, hypoglycaemia, respectively. After adjusting for baseline characteristics, hypoglycaemia was associated with significantly increased hazards for any accident [hazard ratio (HR) 1.39, 95% CI 1.21–1.59, p < 0.001], accidental falls (HR 1.36, 95% CI 1.13–1.65, p < 0.001) and motor vehicle accidents (HR 1.82, 95% CI 1.18–2.80, p = 0.007). In age‐stratified analyses, hypoglycaemia was associated with greater hazards of driving‐related accidents in people younger than age 65 and falls in people aged 65 or older.

Conclusions

In people with type 2 diabetes receiving antidiabetes drugs without insulin, hypoglycaemia was associated with a significantly higher risk of accidents resulting in hospital visits, including accidents related to driving and falls.
Temporal changes of soluble ST2 after cardiovascular interventions
Authors: Willems Sanne , Sels Jan‐Willem , Flier Suzanne , Versteeg Dik , Buhre Wolfgang F. , de Kleijn Dominique P.V. , Hoefer Imo E. , Pasterkamp Gerard
Published: November 2012

Background

Soluble ST2 (sST2), a member of the IL‐1 receptor family, has been proposed as a novel biomarker with predictive value for heart failure and mortality in patients suffering from cardiovascular diseases. The influence of clinical characteristics on variability of sST2 levels is relatively unexplored. Here, we studied the effect of cardiovascular interventions and clinical characteristics on plasma sST2 expression levels.

Material and methods

In the current study, sST2 levels were assessed in the plasma of patients scheduled for coronary artery bypass grafting (CABG) (n = 76), percutaneous coronary intervention (PCI) (n = 68) or peripheral vascular surgery (n = 27).

Results

Age was the only classical risk factor significantly correlating with sST2 levels. Soluble ST2 levels were significantly increased 1 h after CABG (48 [33–70] vs. 61 [42–89] pg/mL, P = 0·001) and increased even further after 24 h (1116 [578–13 666] pg/mL, P < 0·001). An average threefold increase in sST2 levels was also observed in patients 24 h after peripheral interventions (30 [21–41] vs. 98 [48–211] pg/mL, P < 0·001). Two months after PCI, we found that sST2 levels were significantly higher compared with baseline levels (41 [29–61] vs. 48 [31–80] pg/mL, P = 0·007, n = 52). In addition, we did not observe an association between sST2 and any inflammatory or cardiac‐specific markers that were measured in this study.

Conclusions

Soluble ST2 increases significantly following cardiovascular interventions. The notion of a recent cardiovascular intervention is a strong determinant of sST2 levels and therefore needs to be taken into account when exploring sST2 as predictor of future cardiovascular events.
Seasonal differences in the diel movements of Macquarie perch (Macquaria australasica) in an upland reservoir
Authors: Thiem Jason D. , Broadhurst Ben T. , Lintermans Mark , Ebner Brendan C. , Clear Rhian C. , Wright Daniel
Published: November 2012

Knowledge of the movement patterns of threatened fishes aids their conservation management and informs sustainable development of natural resources including freshwater. Prior to the expansion of a temperate upland reservoir in Australia, we used radio telemetry to compare seasonal differences in the diel movements of adult endangered Macquarie perch (Macquaria australasica) (235–414 mm total length) in Cotter Reservoir, Australian Capital Territory. Macquarie perch exhibited a diel range of 389 ± 46 m, a diel mobility of 769 ± 93 m and diel area use of 24008 ± 5595 m2 among four seasons. Diel range was significantly higher in winter compared with other seasons, and diel mobility was negatively correlated with fish size among four seasons. Macquarie perch inhabited deeper water in summer across the diel cycle (7.2 ± 0.5 m) in comparison with other seasons (spring: 3.8 ± 0.3 m, autumn: 3.0 ± 0.2 m, winter: 3.0 ± 0.3 m). Within seasons, both remote and manual telemetry identified that diel activity was predominantly crepuscular. Prey availability and the threat of avian predation represent the most likely explanations for the differences in seasonal movements. In a reservoir where expansion will likely result in a loss of critical habitat (emergent macrophytes) for this endangered species, we use site‐specific knowledge of the spatial ecology of Macquarie perch to inform the placement of shelter habitat prior to filling the enlarged reservoir.
Of mast and mean: differential‐temperature cue makes mast seeding insensitive to climate change
Authors: Kelly Dave , Geldenhuis Andre , James Alex , Penelope Holland E. , Plank Michael J. , Brockie Robert E. , Cowan Philip E. , Harper Grant A. , Lee William G. , Maitland Matt J. , Mark Alan F. , Mills James A. , Wilson Peter R. , Byrom Andrea E.
Published: November 2012

Mast‐seeding plants often produce high seed crops the year after a warm spring or summer, but the warm‐temperature model has inconsistent predictive ability. Here, we show for 26 long‐term data sets from five plant families that the temperature difference between the two previous summers (ΔT) better predicts seed crops. This discovery explains how masting species tailor their flowering patterns to sites across altitudinal temperature gradients; predicts that masting will be unaffected by increasing mean temperatures under climate change; improves prediction of impacts on seed consumers; demonstrates that strongly masting species are hypersensitive to climate; explains the rarity of consecutive high‐seed years without invoking resource constraints; and generates hypotheses about physiological mechanisms in plants and insect seed predators. For plants, ΔT has many attributes of an ideal cue. This temperature‐difference model clarifies our understanding of mast seeding under environmental change, and could also be applied to other cues, such as rainfall.
Beta‐diversity in temperate and tropical forests reflects dissimilar mechanisms of community assembly
Authors: Myers Jonathan A. , Chase Jonathan M. , Jiménez Iván , Jørgensen Peter M. , Araujo‐Murakami Alejandro , Paniagua‐Zambrana Narel , Seidel Renate
Published: November 2012

Site‐to‐site variation in species composition (β‐diversity) generally increases from low‐ to high‐diversity regions. Although biogeographical differences in community assembly mechanisms may explain this pattern, random sampling effects can create this pattern through differences in regional species pools. Here, we compared assembly mechanisms between spatially extensive networks of temperate and tropical forest plots with highly divergent species pools (46 vs. 607 species). After controlling for sampling effects, β‐diversity of woody plants was similar and higher than expected by chance in both forests, reflecting strong intraspecific aggregation. However, different mechanisms appeared to explain aggregation in the two forests. In the temperate forest, aggregation reflected stronger environmental correlations, suggesting an important role for species‐sorting (e.g. environmental filtering) processes, whereas in the tropics, aggregation reflected stronger spatial correlations, more likely reflecting dispersal limitation. We suggest that biogeographical differences in the relative importance of different community assembly mechanisms contribute to these striking gradients in global biodiversity.
Can we predict the evolution of an unpredictable disease like multiple sclerosis?
Authors: Bergamaschi R.
Published: November 2012

Click here to view the accompanying paper in this issue.
Genetic analysis of the FUS/TLS gene in essential tremor
Authors: Parmalee N. , Mirzozoda K. , Kisselev S. , Merner N. , Dion P. , Rouleau G. , Clark L. , Louis E. D.
Published: November 2012

Background and purpose

Although essential tremor (ET) has a genetic basis, specific genes have not been identified. Recently, in a large ET family (FET1) from Quebec, a non‐sense mutation (p.Q290X) in the amyotrophic lateral sclerosis (ALS) gene fused in sarcoma/translated in liposarcoma (FUS/TLS) was identified by exome sequencing. No confirmatory studies have been published.

Methods

Two‐hundred and fifty‐nine ET cases and 262 controls were enrolled in a study at Columbia University. We performed a comprehensive analysis of the FUS/TLS gene by sequencing all exons in a subsample of 116 ET cases with early‐onset (≤40 years) ET. We evaluated an association between ET and SNPs in the FUS/TLS gene by genotyping four haplotype tagging SNPs in all 259 ET cases and 262 controls. Additionally, seven variants associated with ALS, two variants of unknown pathogenicity detected in ALS cases, eight mis‐sense variants predicted to be damaging, and six rare variants were genotyped in these 259 ET cases and 262 controls.

Results

FUS/TLS mutations previously reported in ALS, the FET1 family, or novel mutations were not found in any of the 116 early‐onset ET cases. In the case–control analyses, although the power of the performed associations was limited, no significant association between tagging SNPs in FUS/TLS and ET was observed, and none of the analyzed SNPs showed evidence of association with ET.

Conclusion

Our study suggests that pathogenic mutations in FUS/TLS are rare in a sample of early‐onset ET cases in North America. We did not find evidence that the FUS/TLS gene is a risk factor for ET.