bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid Kinetic Labeling of Arabidopsis Cell Suspension Cultures: Implications for Models of Lipid Export from Plastids
Authors: Tjellström Henrik , Yang Zhenle , Allen Doug K. , Ohlrogge John B.
Published: December 2011

Cell cultures allow rapid kinetic labeling experiments that can provide information on precursor-product relationships and intermediate pools. T-87 suspension cells are increasingly used in Arabidopsis (Arabidopsis thaliana) research, but there are no reports describing their lipid composition or biosynthesis. To facilitate application of T-87 cells for analysis of glycerolipid metabolism, including tests of gene functions, we determined composition and accumulation of lipids of light- and dark-grown cultures. Fatty acid synthesis in T-87 cells was 7- to 8-fold higher than in leaves. Similar to other plant tissues, phosphatidylcholine (PC) and phosphatidylethanolamine were major phospholipids, but galactolipid levels were 3- to 4-fold lower than Arabidopsis leaves. Triacylglycerol represented 10% of total acyl chains, a greater percentage than in most nonseed tissues. The initial steps in T-87 cell lipid assembly were evaluated by pulse labeling cultures with [14C]acetate and [14C]glycerol. [14C]acetate was very rapidly incorporated into PC, preferentially at sn-2 and without an apparent precursor-product relationship to diacylglycerol (DAG). By contrast, [14C]glycerol most rapidly labeled DAG. These results indicate that acyl editing of PC is the major pathway for initial incorporation of fatty acids into glycerolipids of cells derived from a 16:3 plant. A very short lag time (5.4 s) for [14C]acetate labeling of PC implied channeled incorporation of acyl chains without mixing with the bulk acyl-CoA pool. Subcellular fractionation of pea (Pisum sativum) leaf protoplasts indicated that 30% of lysophosphatidylcholine acyltransferase activity colocalized with chloroplasts. Together, these data support a model in which PC participates in trafficking of newly synthesized acyl chains from plastids to the endoplasmic reticulum.
Plastid Proteome Assembly without Toc159: Photosynthetic Protein Import and Accumulation of N-Acetylated Plastid Precursor Proteins
Authors: Bischof Sylvain , Baerenfaller Katja , Wildhaber Thomas , Troesch Raphael , Vidi Pierre-Alexandre , Roschitzki Bernd , Hirsch-Hoffmann Matthias , Hennig Lars , Kessler Felix , Gruissem Wilhelm , Baginsky Sacha
Published: December 2011

Import of nuclear-encoded precursor proteins from the cytosol is an essential step in chloroplast biogenesis that is mediated by protein translocon complexes at the inner and outer envelope membrane (TOC). Toc159 is thought to be the main receptor for photosynthetic proteins, but lacking a large-scale systems approach, this hypothesis has only been tested for a handful of photosynthetic and nonphotosynthetic proteins. To assess Toc159 precursor specificity, we quantitatively analyzed the accumulation of plastid proteins in two mutant lines deficient in this receptor. Parallel genome-wide transcript profiling allowed us to discern the consequences of impaired protein import from systemic transcriptional responses that contribute to the loss of photosynthetic capacity. On this basis, we defined putative Toc159-independent and Toc159-dependent precursor proteins. Many photosynthetic proteins accumulate in Toc159-deficient plastids, and, surprisingly, several distinct metabolic pathways are negatively affected by Toc159 depletion. Lack of Toc159 furthermore affects several proteins that accumulate as unprocessed N-acetylated precursor proteins outside of plastids. Together, our data show an unexpected client protein promiscuity of Toc159 that requires a far more differentiated view of Toc159 receptor function and regulation of plastid protein import, in which cytosolic Met removal followed by N-terminal acetylation of precursors emerges as an additional regulatory step.
Revisiting issues, drawbacks and opportunities with observational studies in comparative effectiveness research
Authors: Alemayehu Demissie , Cappelleri Joseph C.
Published: December 2011

Rationale  Despite their inherently pervasive limitations, data from observational studies are increasingly relied upon by health care decision makers to fill critical information gaps created by lack of evidence from randomized controlled trials.

Aim and objective  The aim and objective of this article was to revisit the major issues associated with observational studies from secondary data sources.

Method  The method of this article was canvass of the literature.

Results  Sources of bias are highlighted and steps intended to minimize bias are summarized.

Conclusion  Efforts should be made to improve causal inference of treatment effects from observational studies found in secondary data sources. Extra care and caution should be exercised in the interpretation and reporting of results from these studies.
Attitude, knowledge and behaviour towards evidence‐based medicine of physical therapists, students, teachers and supervisors in the Netherlands: a survey
Authors: Scholten‐Peeters Gwendolijne G. M. , Beekman‐Evers Monique S. , van Boxel Annemiek C. J. W. , van Hemert Sjanna , Paulis Winifred D. , van der Wouden Johannes C. , Verhagen Arianne P.
Published: December 2011

Rationale, aims and objectives  Evidence‐based medicine (EBM) has gained widespread acceptance in physical therapy. However, because little is known about the attitudes, knowledge and behaviour of physical therapists towards EBM, and their participation in research to generate EBM, we explored these aspects among physical therapy students, teachers, supervisors and practising physical therapists.

Methods  This is a cross‐sectional survey in which participants completed a web‐based questionnaire to determine their attitudes, knowledge and behaviour regarding EBM, and their participation in research.

Results  Questionnaires were sent to 814 participants of which 165 were returned. The overall mean score for attitude was 4.3 [standard deviation (SD) 1.0; range 1–7], which indicates a weak positive attitude. Teachers scored the highest (4.9, SD 1.2) and students the lowest (4.1, SD 0.8). Although most participants had some understanding of the technical terms used in EBM, only teachers felt able to explain these terms to others. Of the students, 45% rated their perceived EBM knowledge as bad and 45% as average, whereas 78% of the teachers considered that they had good knowledge. To answer clinical questions, most students generally use textbooks (96%) and the opinion of their supervisors (87.7%).

Conclusions  There is a weak positive attitude of physical therapists, teachers, supervisors and students towards participating in research in general practice, but there is a lack of knowledge and active behaviour regarding EBM, especially among physical therapy students.
Heterozygosity predicts clutch and egg size but not plasticity in a house sparrow population with no evidence of inbreeding
Authors: WETZEL DANIEL P. , STEWART IAN R. K. , WESTNEAT DAVID F.
Published: December 2011

We investigated the link between heterozygosity and the reaction norm attributes of reproductive performance in female house sparrows (Passer domesticus). We collected data on clutch size, egg size, hatching success and nestling survival in 2816 nesting attempts made by 791 marked individuals over a 16‐year period. Pedigree analysis revealed no evidence of inbreeding. Neither parent–offspring regression nor an animal model revealed significant heritability in clutch or egg size. We selected 42 females that laid at least seven clutches at our study site and used a survey of 21 autosomal microsatellite loci to estimate heterozygosity for each female. We controlled for phenotypic plasticity and found that both clutch and egg size showed significant positive correlations with heterozygosity. We found no evidence that heterozygosity influenced the slope of individual reaction norms. Further analysis suggested that clutch size was affected by heterozygosity across the genome, but egg size had more complex relationships, with evidence favouring the influence of multiple loci. Given the apparent lack of inbreeding and large population size, our results suggest associative overdominance as the likely mechanism for the impact of heterozygosity, but also created a puzzle about the process producing associations between neutral markers and the genes affecting clutch size or egg size. One possible explanation is a long‐term residual effect of the historical bottleneck that occurred when house sparrows were introduced into North America. The existence of heterozygosity‐fitness correlations in a population with considerable phenotypic plasticity and little inbreeding implies that the effects of heterozygosity may be more significant than previously thought.
Transient expression of pepper Bs2 gene in Citrus limon as an approach to evaluate its utility for management of citrus canker disease
Authors: Sendín L. N. , Filippone M. P. , Orce I. G. , Rigano L. , Enrique R. , Peña L. , Vojnov A. A. , Marano M. R. , Castagnaro A. P.
Published: December 2011

The pepper Bs2 gene confers resistance to Xanthomonas campestris pv. vesicatoria (Xcv) pathogenic strains containing the avrBs2 avirulence gene in susceptible pepper and tomato. The avrBs2 gene is highly conserved in the Xanthomonas genus and when bacteria lack this gene their growth in a susceptible host is diminished, indicating that the avrBs2 gene product could confer an adaptive advantage to the pathogen. The avrBs2 of Xanthomonas citri subsp. citri (Xcc), cause of citrus canker, shares 96% homology with avrBs2 of Xcv. To evaluate if Bs2 could recognize avrBs2 of Xcc in citrus plants and thereby activate plant defence mechanisms to increase resistance to canker, transient expression experiments were conducted using Agrobacterium tumefaciens in lemon plants subsequently challenged with wildtype Xcc. The results showed that transient expression of Bs2 reduced canker formation in lemon and induced plant defence mechanisms, as shown by callose deposition and PR‐1 expression. Moreover, when an avrBs2 mutant of Xcc was used, no decrease in disease symptoms was observed. This work shows that the Bs2 gene from Solanaceae is functional in lemon, a member of the Rutaceae family. Therefore, Bs2 is a potential candidate gene for stable expression in transgenic citrus plants in order to improve resistance to canker disease.
Environmental enrichment blocks ethanol‐induced locomotor sensitization and decreases BDNF levels in the prefrontal cortex in mice
Authors: Rueda André Veloso Lima , Teixeira Ana Maria Aristimunho , Yonamine Mauricio , Camarini Rosana
Published: December 2011

The use of addictive drugs can lead to long‐term neuroplastic changes in the brain, including behavioral sensitization, a phenomenon related to addiction. Environmental enrichment (EE) is a strategy used to study the effect of environment on the response to several manipulations, including treatment with addictive drugs. Brain‐derived neurotrophic factor (BDNF) has been associated with behaviors related to ethanol addiction. The aim of the present study was to evaluate the effects of EE on ethanol‐induced behavioral sensitization and BDNF expression. Mice were exposed to EE and then repeatedly treated with a low dose (1.8 g/kg) of ethanol. Another group of mice was first subjected to repeated ethanol treatment according to the behavioral sensitization protocol and then exposed to EE. Environmental enrichment prevented the development of ethanol‐induced behavioral sensitization and blocked behavioral sensitization in sensitized mice. Both repeated ethanol and EE decreased BDNF levels in the prefrontal cortex but not in the hippocampus. However, BDNF levels were lower in ethanol‐treated mice exposed to EE. These findings suggest that EE can act on the mechanisms implicated in behavioral sensitization, a model for drug‐induced neuroplasticity and relapse. Additionally, EE alters BDNF levels, which regulate addiction‐related behaviors.
Basophil allergen threshold sensitivity, CD‐sens, IgE‐sensitization and DBPCFC in peanut‐sensitized children
Authors: Glaumann S. , Nopp A. , Johansson S. G. O. , Rudengren M. , Borres M. P. , Nilsson C.
Published: December 2011

To cite this article: Glaumann S, Nopp A, Johansson SGO, Rudengren M, Borres MP, Nilsson C. Basophil allergen threshold sensitivity, CD‐sens, IgE‐sensitization and DBPCFC in peanut‐sensitized children. Allergy 2012; 67: 242–247.

Background:  Immunoglobulin E (IgE)‐sensitization to peanut is common and can indicate an allergy. A positive test needs to be confirmed by a double‐blind, placebo‐controlled food challenge (DBPCFC), which is regarded as ‘the gold standard’. The aim of the study was to evaluate the basophil allergen threshold sensitivity (CD‐sens) and antibodies to peanut allergen components in relation to DBPCFC in the diagnoses of peanut allergy in children.

Methods:  Thirty‐eight children with suspected peanut allergy underwent a DBPCFC. CD‐sens to peanut and Ara h 2 were analysed as well as IgE‐antibody to peanut and some of its allergen components (Ara h 1, 2, 3, 8 and 9).

Results:  Twenty‐five children had a positive DBPCFC, and 92% of these were positive in CD‐sens to peanut and Ara h 2. Two children with a positive DBPCFC were classified as ‘low‐responders’ and were not further evaluated. Children positive in DBPCFC had higher CD‐sens values to peanut (median 1.3; range 0.4–29, n = 21) compared with children negative in DBPCFC (median 0; range 0–0.5, n = 13) (P < 0.0001). A positive DBPCFC correspond with increased levels of IgE‐antibody to Ara h 1, 2 and 3 compared with those with a negative challenge (P < 0.0001 for all). All children with a negative CD‐sens were negative in DBPCFC.

Conclusion:  In this study, a negative CD‐sens to peanut excluded peanut allergy. Both tests, CD‐sens to peanut and immunoassay for IgE‐antibody to the peanut components, appear to be safe, time saving and cost‐effective complements to DBPCFC.
Successful treatment of disseminated fusariosis with voriconazole in an acute lymphoblastic leukaemia patient
Authors: Labois Aurelie , Gray Christian , Lepretre Stephane
Published: December 2011

Fusarium species are actually the second most common pathogenic mould in immunocompromised patients, and it is difficult to treat such fusarial infections with current antifungal agents. We report the case of a 53‐year‐old woman with Philadelphia‐positive acute lymphoblastic leukaemia. During induction chemotherapy with febrile neutropenia, she developed a disseminated fusariosis, with persistent fever refractory to antibacterial agents and caspofungin (as empirical therapy), painful skin lesions and respiratory impairment. Fusarium solani was isolated from skin biopsy. Voriconazole was successfully implemented as antifungal curative therapy. During the second intensive chemotherapy no reactivation of fusariosis was detected.
Recurrent candidaemia and pacemaker wire infection with Candida albicans
Authors: Glöckner A.
Published: December 2011

Recurrent candidaemia is both a cause and a symptom of deep organ candidiasis or infection of foreign bodies (e.g. central venous line, other indwelling catheter or pacemaker wire) and is associated with significant morbidity and mortality. This case report demonstrates that in the event of pacemaker wire infection with Candida and when it is not possible to remove the infected pacemaker wire, treatment with an echinocandin, such as anidulafungin, can be safe and successful.
Candida tropicalis pylephlebitis with persistent fungaemia in a 72‐year‐old lady with severe pancreatitis
Authors: Meersseman Wouter
Published: December 2011

Pylephlebitis is defined as septic thrombophlebitis of the portal venous system, usually secondary to infection or inflammation in the abdomen. In the current report, we present a case of fungal pylephlebitis that complicated the course of pancreatitis and resolved with echinocandins.
Evaluation of fluorescence in situ hybridisation (FISH) for the identification of Candida albicans in comparison with three phenotypic methods
Authors: Lakner Anna , Essig Andreas , Frickmann Hagen , Poppert Sven
Published: December 2011

Severe Candida infections are increasing and are associated with considerable morbidity and mortality. Rapid and accurate differentiation of Candida albicans from non‐C. albicans species is essential for therapeutic decisions. We therefore developed a fluorescence in situ hybridisation (FISH) assay comprising previously described probes and a newly designed specific C. albicans probe/competitor probe combination. The FISH probes were first evaluated using 99 selected fungal strains covering 31 species, and a specificity between 96% and 100% and a sensitivity of 100%. The FISH assay was then applied to 110 clinical isolates in parallel with API32C, the chromogenic Candida ID agar, and determination of filamentous colony morphology. All tests produced highly reliable results. However, the Candida ID agar misidentified Candida dubliniensis as C. albicans. Determination of filamentous colony morphology allowed 100% reliable identification of C. albicans, but took 48 h. FISH allowed identification of clinical C. albicans isolates within 3 h with a sensitivity and specificity of 100%. FISH was additionally applied to 48 blood cultures showing yeasts in the Gram stain and correctly identified all 33 cases of C. albicans.
Early origins of heart disease: Low birth weight and determinants of cardiomyocyte endowment
Authors: Botting KJ , Wang KCW , Padhee M , McMillen IC , Summers‐Pearce B , Rattanatray L , Cutri N , Posterino GS , Brooks DA , Morrison JL
Published: December 2011

1. World‐wide epidemiological and experimental animal studies demonstrate that adversity in fetal life, resulting in intrauterine growth restriction, programmes the offspring for a greater susceptibility to ischaemic heart disease and heart failure in adult life.

2. After cardiogenesis, cardiomyocyte endowment is determined by a range of hormones and signalling pathways that regulate cardiomyocyte proliferation, apoptosis and the timing of multinucleation/terminal differentiation.

3. The small fetus may have reduced cardiomyocyte endowment owing to the impact of a suboptimal intrauterine environment on the signalling pathways that regulate cardiomyocyte proliferation, apoptosis and the timing of terminal differentiation.
Intraductal papillary neoplasm arising from peribiliary glands connecting with the inferior branch of the bile duct of the anterior segment of the liver
Authors: Nakanishi Yoshitsugu , Nakanuma Yasuni , Ohara Masanori , Iwao Toshiyasu , Kimura Noriko , Ishidate Takuzo , Kijima Hiroshi
Published: December 2011

Intraductal papillary neoplasms of the bile duct are generally thought to arise from neoplastic papillary proliferation of epithelial cells lining the bile duct. We herein report a case with findings that strongly suggested that the biliary cystic tumor might have derived from a peribiliary gland. A 69‐year‐old female was found to have a cystic lesion with intracystic protrusions at the anterior segment of the right hepatic lobe and underwent hepatic anterior segment resection. Fluoroscopy of the resected specimen injected with contrast medium into the cyst revealed a connection between the cystic lesion and the bile ducts. The cyst was multilocular in appearance. On microscopic examination, the cyst was located within the portal tract of the inferior branch of the anterior segment and connected with the inferior branch of the bile duct. The wall of the hepatic cyst lacked an ovarian‐like stroma. The tumor was composed of papillary and glandular components, and the tumor cells were similar to gastric foveolar and pyloric gland epithelia and regarded as adenoma. These tumor cells were positive for MUC 5AC, MUC6, and HIK1083. The tumor was finally diagnosed as an intraductal papillary neoplasm of the bile duct (adenoma, gastric type) arising from a peribiliary gland.
Evidence of bladder oversensitivity in the absence of an infection in premenopausal women with a history of recurrent urinary tract infections
Authors: Arya Lily A. , Northington Gina M. , Asfaw Tirsit , Harvie Heidi , Malykhina Anna
Published: December 2011

Study Type – Prevalence (case control)

Level of Evidence 4

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

Urinary tract infections (UTIs) have been implicated in the aetiology of interstitial cystitis/painful bladder syndrome (IC/PBS). Prior studies have described symptoms and laboratory tests suggestive of UTI at the onset of IC/PBS as well as a significant history of childhood recurrent UTIs. However, the mechanism by which recurrent UTIs contribute to the development of IC/PBS is not clear.

Our study shows that women with recurrent UTI suffer from bladder oversensitivity. Our findings have useful clinical implications. Women with bladder oversensitivity complain of urinary frequency which is often misdiagnosed as an infection and treated with unnecessary antibiotics. Additionally, there are no effective therapies for bladder oversensitivity. Therefore, women with recurrent UTI should undergo prompt evaluation and treatment of episodes of infection to prevent the development of bladder oversensitivity. Our findings also provide a possible mechanism for the development of IC/PBS. Whether women with recurrent UTI are at increased risk for developing IC/PBS in the future will need to be confirmed in future studies.

OBJECTIVE

To compare the mean voided volume and bladder sensation during filling cystometry in women with a history of recurrent urinary tract infection (UTI) and controls.

PATIENTS AND METHODS

This was a case–control study including adult women seen in the urogynaecology clinic.

The cases were 49 women with at least three documented positive urine cultures >105 colonies/mL in the previous 12 months and no active infection at the time of data collection.

Controls were 53 women with stress urinary incontinence and no history of recurrent UTI or coexistent urge urinary incontinence.

We compared bladder diary variables and filling cystometry data in the absence of an active infection.

RESULTS

There was no significant difference in the median age, parity and body mass index of women with a history of recurrent UTI and controls.

The median number of voids per day and median number of voids per litre of fluid intake was significantly greater in women with recurrent UTI than controls (12 vs 7 voids/day and 6 vs 4 voids/L, P= 0.005 and P= 0.004 respectively).

The median average voided volume was significantly lower in women with recurrent UTI than controls (155 vs 195 mL, P= 0.008).

On filling cystometry, median volumes of strong desire to void and maximum cystometric capacity were significantly lower in women with recurrent UTI than controls (all P < 0.05).

CONCLUSION

In the absence of an infection, premenopausal women with a history of recurrent UTI have significantly greater urinary frequency, lower average voided volume and a lower threshold of bladder sensitivity than controls.
Therapist attentiveness and negative capability in dialogical family meetings for psychosis
Authors: Reed Alex
Published: December 2011

Jaakko Seikkula (2008) has pointed towards the importance of practitioners working in the present moment in dialogical therapy. Extrapolating from Seikkula's work, this article considers the significance of the qualities of therapist attentiveness, generosity and negative capability in dialogical family meetings for psychosis. It is proposed that these qualities are of particular importance when family meetings occur in crisis situations, as when under pressure practitioners can easily be drawn into prematurely interventionist stances that may unintentionally promote chronicity for the person experiencing psychosis. The value of co‐working arrangements in enabling practitioners to maintain attentiveness and negative capability in this work is also considered.
Cellulose factories: advancing bioenergy production from forest trees
Authors: Mizrachi Eshchar , Mansfield Shawn D. , Myburg Alexander A.
Published: December 2011

Fast‐growing, short‐rotation forest trees, such as Populus and Eucalyptus, produce large amounts of cellulose‐rich biomass that could be utilized for bioenergy and biopolymer production. Major obstacles need to be overcome before the deployment of these genera as energy crops, including the effective removal of lignin and the subsequent liberation of carbohydrate constituents from wood cell walls. However, significant opportunities exist to both select for and engineer the structure and interaction of cell wall biopolymers, which could afford a means to improve processing and product development. The molecular underpinnings and regulation of cell wall carbohydrate biosynthesis are rapidly being elucidated, and are providing tools to strategically develop and guide the targeted modification required to adapt forest trees for the emerging bioeconomy. Much insight has already been gained from the perturbation of individual genes and pathways, but it is not known to what extent the natural variation in the sequence and expression of these same genes underlies the inherent variation in wood properties of field‐grown trees. The integration of data from next‐generation genomic technologies applied in natural and experimental populations will enable a systems genetics approach to study cell wall carbohydrate production in trees, and should advance the development of future woody bioenergy and biopolymer crops.
Amplification success of multilocus genotypes from feathers found in the field compared with feathers obtained from shot birds
Authors: JOHANSSON MAGNUS P. , MCMAHON BARRY J. , HÖGLUND JACOB , SEGELBACHER GERNOT
Published: December 2011

Effective DNA extraction methods from bird feathers have facilitated non‐invasive sampling, leading to the suggestion that feathers are a great source for genetic studies. However, few studies have assessed whether all feathers can be used or provide equal numbers of useful templates. In this study, feathers collected in various ways from Red Grouse Lagopus lagopus were examined to establish the quality of DNA extracted. Individual samples were classified into two categories according to whether they were collected from shot birds or found in the field. DNA was extracted from all samples and genotyped at 19 microsatellite loci. PCR products were analysed on a MegaBACE 1000. A total of 93% of the ‘shot’ category produced a genotype that was considered successful (i.e. 15 of 18 loci) and 23% of the ‘collected’ category produced successful genotypes under the same criteria. There was a significant difference between shot and collected samples in genotyping success and the observed number of missing loci. Recommendations and best practices are discussed along with the utility of bird feathers as a source of DNA for population and conservation biology.
Geographic variation in the age‐ and gender‐specific prevalence and incidence of epilepsy: Analysis of Taiwanese National Health Insurance–based data
Authors: Chen Chih‐Chuan , Chen Li‐Sheng , Yen Ming‐Fang , Chen Hsiu‐Hsi , Liou Horng‐Huei
Published: December 2011

Purpose:  We studied geographic variation in age‐ and gender‐specific prevalence and incidence of epilepsy in four different areas of Taiwan.

Methods:  By using large‐scale, National Health Insurance (NHI)–based data from 2000–2003 in Taiwan, we identified 131,287 patients diagnosed with epilepsy (ICD code 345) receiving at least of one of 11 antiepileptic drugs (AEDs). Information on age, gender, and location were also collected. The multivariable Poisson regression analysis was used to assess the heterogeneity of the morbidity of epilepsy in different regions. External data validation was also performed to assess the accuracy of capturing epilepsy cases through our NHI data set.

Key Findings:  The age‐adjusted prevalence and incidence of epilepsy were 5.85 (per 1,000) between 2000 and 2003 and 97 (per 100,000 person‐years) during the follow‐up time from 2001 to 2003 in Taiwan. The sensitivity and specificity of ICD‐9 coding for epilepsy in the NHI data set were 83.91% and 99.83%, respectively, resulting in a slight overestimation. Male patients had a higher probability of having epilepsy than did females. East Taiwan had significantly higher prevalence and incidence than did other areas. The age‐specific incidence pattern in east Taiwan was atypical in that it revealed clustering in young and middle‐aged groups.

Significance:  Our study demonstrated geographic variation in epidemiologic patterns of epilepsy within Taiwan. The findings are informative and provide insight into the clinical management of epilepsy based on consideration of different target groups in different areas.
Gray matter loss correlates with mesial temporal lobe neuronal hyperexcitability inside the human seizure‐onset zone
Authors: Staba Richard J. , Ekstrom Arne D. , Suthana Nanthia A. , Burggren Alison , Fried Itzhak , Engel Jerome , Bookheimer Susan Y.
Published: December 2011

Purpose:  Patient studies have not provided consistent evidence for interictal neuronal hyperexcitability inside the seizure‐onset zone (SOZ). We hypothesized that gray matter (GM) loss could have important effects on neuronal firing, and quantifying these effects would reveal significant differences in neuronal firing inside versus outside the SOZ.

Methods:  Magnetic resonance imaging (MRI) and computational unfolding of mesial temporal lobe (MTL) subregions was used to construct anatomic maps to compute GM loss in presurgical patients with medically intractable focal seizures in relation to controls. In patients, these same maps were used to locate the position of microelectrodes that recorded interictal neuronal activity. Single neuron firing and burst rates were evaluated in relation to GM loss and MTL subregions inside and outside the SOZ.

Key Findings:  MTL GM thickness was reduced inside and outside the SOZ in patients with respect to controls, yet GM loss was associated more strongly with firing and burst rates in several MTL subregions inside the SOZ. Adjusting single neuron firing and burst rates for the effects of GM loss revealed significantly higher firing rates in the subregion consisting of dentate gyrus and CA2 and CA3 (CA23DG), as well as CA1 and entorhinal cortex (EC) inside versus outside the SOZ where normalized MRI GM loss was ≥1.40 mm. Firing rates were higher in subicular cortex inside the SOZ at GM loss ≥1.97 mm, whereas burst rates were higher in CA23DG, CA1, and EC inside than outside the SOZ at similar levels of GM loss.

Significance:  The correlation between GM loss and increased firing and burst rates suggests GM structural alterations in MTL subregions are associated with interictal neuronal hyperexcitability inside the SOZ. Significant differences in firing rates and bursting in areas with GM loss inside compared to outside the SOZ indicate that synaptic reorganization following cell loss could be associated with varying degrees of epileptogenicity in patients with intractable focal seizures.
The Value of Reducing Cancer Risks at Contaminated Sites: Are More Knowledgeable People Willing to Pay More?
Authors: Tonin Stefania , Alberini Anna , Turvani Margherita
Published: December 2011

We use conjoint choice questions to investigate people's tastes for cancer risk reductions and income in the context of public programs that would provide for remediation at abandoned industrial contaminated sites. Our survey was self‐administered using the computer by persons living in the vicinity of an important contaminated site on the Italian National Priority List. The value of a prevented case of cancer is €2.6 million, but this figure does vary with income, perceived exposure to contaminants, and respondent opinions about priorities that should be pursued by cleanup programs.
Suppression of Torsades de Pointes by Biventricular Pacing in a Patient with Long QT Syndrome
Authors: MIYOSHI FUMITO , TANNO KAORU , KOBAYASHI YOUICHI
Published: December 2011

This report describes a case of a patient with long QT syndrome (LQTS) with recurrent episodes of torsades de pointes (TdP). Use of biventricular pacing (BiVP) resulted in a shorter QT interval and a shorter T‐peak‐end interval and prevented further episodes of TdP. These findings suggest that BiVP may be helpful in patients with LQTS and refractory TdP.
Activation of the prolyl‐hydroxylase oxygen‐sensing signal cascade leads to AMPK activation in cardiomyocytes
Authors: Yan Hong , Zhang Dong‐Xia , Shi Xiaohua , Zhang Qiong , Huang Yue‐Sheng
Published: December 2011

The proline hydroxylase domain‐containing enzymes (PHD) act as cellular oxygen sensors and initiate a hypoxic signal cascade to induce a range of cellular responses to hypoxia especially in the aspect of energy and metabolic homeostasis regulation. AMP‐activated protein kinase (AMPK) is recognized as a major energetic sensor and regulator of cardiac metabolism. However, the effect of PHD signal on AMPK has never been studied before. A PHD inhibitor (PHI), dimethyloxalylglycine and PHD2‐specific RNA interference (RNAi) have been used to activate PHD signalling in neonatal rat cardiomyocytes. Both PHI and PHD2‐RNAi activated AMPK pathway in cardiomyocytes effectively. In addition, the increased glucose uptake during normoxia and enhanced myocyte viability during hypoxia induced by PHI pretreatment were abrogated substantially upon AMPK inhibition with an adenoviral vector expressing a dominant negative mutant of AMPK‐α1. Furthermore, chelation of intracellular Ca2+ by BAPTA, inhibition of calmodulin‐dependent kinase kinase (CaMKK) with STO‐609, or RNAi‐mediated down‐regulation of CaMKK α inhibited PHI‐induced AMPK activation significantly. In contrast, down‐regulation of LKB1 with adenoviruses expressing the dominant negative form did not affect PHI‐induced AMPK activation. We establish for the first time that activation of PHD signal cascade can activate AMPK pathway mainly through a Ca2+/CaMKK‐dependent mechanism in cardiomyocytes. Furthermore, activation of AMPK plays an essential role in hypoxic protective responses induced by PHI.
Patterning skin by planar cell polarity: the multi‐talented hair designer
Authors: Chen Jiang , Chuong Cheng‐Ming
Published: December 2011

Abstract:  In mammals, the skin can form complex global and local patterns to meet diverse functional requirements in different parts of the body. To date, the fundamental principles that underlie skin patterning remain poorly understood because of the involvement of multiple interacting processes. Genes involved in the planar cell polarity (PCP) signalling pathway, which is capable of polarizing cells within the planar plane of an epithelium, can control the orientation and differentiation of hair follicles, underlining their involvement in skin pattern formation. Here, we summarize recent progress that has been made to understand the PCP signalling pathway and its function in mammalian skin, including its role in hair follicle morphogenesis, ciliogenesis and wound healing. We argue that dissecting PCP signalling in the context of hair follicle formation might reveal many as‐yet‐undiscovered functions for PCP in the development, homeostasis and regeneration of skin.
What happens below the canopy? Direct and indirect influences of the dominant species on forest vertical layers
Authors: Yuan Zuoqiang , Gazol Antonio , Wang Xugao , Xing Dingliang , Lin Fei , Bai Xuejiao , Zhao Yuqiang , Li Buhang , Hao Zhanqing
Published: December 2011

Temperate forests are one of the most important ecosystems in the world, and thus disentangling the factors that drive diversity within these ecosystems is of major concern. However, due to the complex interactions among forests layers, topography and soil factors, discovering the drivers of diversity is often complicated. In this study, we tested three a priori hypotheses about the effect of the dominant competitor (Pinus koraiensis) on the different forest layers in a 25 ha full mapped plot of temperate forest in the Changbai Mountain of northeastern China. Structural equation modelling (SEM) was used to study the direct and indirect interactions between four vertical forest layers (dominant competitor, canopy composition, sub‐canopy diversity and shrub diversity), topographic factors, edaphic factors to discover sub‐canopy and shrub diversity drivers. Our results suggest that the dominant competitor (Pinus koraiensis) is a key factor explaining canopy variation, and sub‐canopy diversity and shrub diversity, and that this competitor can act directly (through shading) and indirectly (through the modification of the soil). Topographic heterogeneity also had significant effects on the soil variation and the diversity of the sub‐canopy and shrub layers. Finally our results indicate that the influence of canopy composition on the diversity of the rest of forest layers is indirect and positive, suggesting that the dominant competitor is the main factor limiting diversity.

In conclusion, we have found strong evidence that the dominant species of the canopy can influence, both directly and indirectly, the diversity of the different vertical forest layers. Patterns of diversity in forests are driven by a multiplicity of factors that are inherently related.
Dominant species and dispersal limitation regulate tree species distributions in a 20‐ha plot in Xishuangbanna, southwest China
Authors: Hu Yue‐Hua , Sha Li‐Qing , Blanchet F. Guillaume , Zhang Jiao‐Lin , Tang Yong , Lan Guo‐Yu , Cao Min
Published: December 2011

Habitat heterogeneity and dispersal limitation are widely considered to be the two major mechanisms in determining tree species distributions. However, few studies have quantified the relative importance of these two mechanisms at different life stages of trees. Moreover, rigorous quantification of the effects of dominant tree species in determining species distributions has seldom been explored. In the present study, we tested the hypothesis that the distribution of tree species is regulated by different mechanisms at different life history stages. In particular, we hypothesised that dispersal limitation regulates the distribution of trees at early life stages and that environmental factors control the distribution of trees as they grow, because of niche differentiation resulting from environmental filtering. To test this, trees in 400‐m2 quadrats in a 20‐ha plot in Xishuangbanna, southwest China were grouped into four classes on the basis of the diameter at breast height (DBH) that roughly represent different stages in the life history of trees. A neighbourhood index was computed to represent a neutral spatial autocorrelation effect. We used both biotic (dominant species) and abiotic (topography and soil) predictor variables to model the distribution of each target species while controlling for spatial autocorrelation within each of the DBH classes. To determine which factors played the largest role in regulating target species distribution, the simulated annealing method was used in model selection based on Akaike information criterion (AIC) values. The results showed that the relative importance of neutral and niche processes in regulating species distribution varied across life stages. The neutral neighbourhood index played the most important role in determining the distributions of small trees (1 cm ≤ DBH ≤ 10 cm), and dominant species, as biotic environmental predictor variables, were the next most important regulators for trees of this size. Environmental predictor variables played the most important role in determining the distributions of large trees (10 cm ≤ DBH). This finding builds on previous research into the relative importance of neutral and niche processes in determining species distributions regardless of life stages or DBH classes.
Sizing up community genetics: it's a matter of scale
Authors: Tack Ayco J. M. , Johnson Marc T. J. , Roslin Tomas
Published: December 2011

The burgeoning field of community genetics posits that genetic variation within species affects the structure and dynamics of associated communities and ecosystems. While many experiments support this hypothesis, we argue that the most commonly employed experimental design suffers from a fundamental flaw that might result in overestimating the importance of genetic variation. Specifically, most studies collect genotypes from a wide area but perform experiments in small common gardens. Since environmental and genetic variation typically increase with spatial scale, this mismatch in scale is predicted to artificially inflate estimates of the ecological importance of genetic effects. Furthermore, most existing studies have used study systems with particular ecological characteristics, which might further inflate the inferred importance of genetic variation. To critically examine this potential problem, we reanalyze previous studies in community genetics and show how current methods lead to biased conclusions. More specifically, while a growing body of literature shows that intraspecific genetic variation can have an effect, it does not accurately estimate its effect size. As a remedy to this bias, we propose an experimental design that can accurately quantify the importance of genetic and environmental variation in affecting communities and ecosystems.
Local variations in turnover of periodontal collagen fibers in rats
Authors: Henneman S. , Reijers R. R. , Maltha J. C. , Von den Hoff J. W.
Published: December 2011

Henneman S, Reijers RR, Maltha JC, Von den Hoff JW. Local variations in turnover of periodontal collagen fibers in rats. J Periodont Res 2012; 47: 383–388. © 2011 John Wiley & Sons A/S

Background and Objective:  The exact cause of orthodontic relapse is still unclear, although it is often suggested to be caused by periodontal collagen fibers. We hypothesize that long‐lived collagen fibers in the periodontium cause relapse. The aim was to determine the half‐life of periodontal collagen fibers around rat molars.

Material and Methods:  Thirty weanling rats were repeatedly injected with 3H‐proline, and autoradiography of histological sections was performed at 1, 4, 8, 15, 22, 29, 36, 57, 78 and 113 d after labeling. Grain densities determined in specific areas of the periodontium were used to calculate collagen half‐life.

Results:  The half‐life (t½) was found to decrease from the supra‐alveolar region to the apical periodontal ligament region. It was longer in the supra‐alveolar region (1.39 ± 0.14 wk) compared with the deeper regions (p < 0.05). The t½ of the upper periodontal ligament region (0.78 ± 0.20 wk) was longer than that of the inter‐radicular periodontal ligament region (0.42 ± 0.07 wk, p < 0.05). The t½ of the apical periodontal ligament region was 0.61 ± 0.15 wk.

Conclusion:  The data indicate that long‐lived collagen fibers do not exist in the soft tissues of the periodontium, and are probably not responsible for relapse. The differences in collagen half‐life might be caused by local variations in compressive strain induced by normal function.
A Relational View of Organizational Restructuring: The Case of Transitional China
Authors: Ma Dali
Published: December 2011

This article addresses three questions concerning authority relations (personal relations with superiors) in transitional China. First, can superiors retain an organizational unit in order to save a protege's job? Second, has instrumental usage of particularistic relations, orguanxi,lost its importance? Third, has ‘principled particularism’, an integration of political loyalty and authority relations, continued to impact careers? Based on first-hand survey data, I find that state-owned enterprises in which managers had closer authority relations were less likely to be sold or discontinued, and close authority relations also reduced the likelihood of career blockage (demotion/lay off). The significant interactive effect of party membership and authority relations revealed the continuation of ‘principled particularism’. The study underlines institutional continuity during rapid social change, renders insights into the processes of organizational restructuring, and depicts the relational base of formal organizations.
Intrinsic regulation of hemoglobin expression by variable subunit interface strengths
Authors: Manning James M. , Popowicz Anthony M. , Padovan Julio C. , Chait Brian T. , Manning Lois R.
Published: December 2011

The expression of the six types of human Hb subunits over time is currently considered to be regulated mainly by transcription factors that bind to upstream control regions of the gene (the ‘extrinsic’ component of regulation). Here, we describe how subunit pairing and further assembly to tetramers in the liganded state is influenced by the affinity of subunits for one another (the ‘intrinsic’ component of regulation). The adult Hb dimers have the strongest subunit interfaces and the embryonic Hbs the weakest, with fetal Hbs being of intermediate strength, corresponding to the temporal order of their expression. These variable subunit binding strengths and the attenuating effects of acetylation contribute to the differences with which these Hb types form functional O2‐binding tetramers consistent with gene switching.
Solution structure of a truncated anti‐MUC1 DNA aptamer determined by mesoscale modeling and NMR
Authors: Baouendi Meriem , Cognet Jean A. H. , Ferreira Catia S. M. , Missailidis Sotiris , Coutant Jérome , Piotto Martial , Hantz Edith , Hervé du Penhoat Catherine
Published: December 2011

Mucin 1 is a well‐established target for the early diagnosis of epithelial cancers. The nucleotides of the S1.3/S2.2 DNA aptamer involved in binding to variable number tandem repeat mucin 1 peptides have been identified using footprinting experiments. The majority of these binding nucleotides are located in the 25‐nucleotide variable region of the total aptamer. Imino proton and 2D NMR spectra of truncated and total aptamers in supercooled water reveal common hydrogen‐bonding networks and point to a similar secondary structure for this 25‐mer sequence alone or embedded within the total aptamer. NMR titration experiments confirm that the TTT triloop structure is the primary binding site and show that the initial structure of the truncated aptamers is conserved upon interaction with variable number tandem repeat peptides. The thermal dependence of the NMR chemical shift data shows that the base‐paired nucleotides melt cooperatively at 47 ± 4 °C. The structure of the 25‐mer oligonucleotide was determined using a new combined mesoscale molecular modeling, molecular dynamics and NMR spectroscopy investigation. It contains three Watson–Crick pairs, three consecutive mispairs and four Watson–Crick pairs capped by a TTT triloop motif. The 3D model structures (PDB 2L5K) and biopolymer chain elasticity molecular models are consistent with both NMR and long unconstrained molecular dynamics (10 ns) in explicit water, respectively.

Database
 Structural data are available in the Protein Data Bank and BioMagResBank databases under the accession numbers 2L5K and 17129, respectively