Protein-binding site at the immunoglobulin mu membrane polyadenylylation signal: possible role in transcription termination.

mRNAs specifying immunoglobulin mu and delta heavy chains are encoded by a single large, complex transcription unit (mu + delta gene). The transcriptional activity of delta gene segments in terminally differentiated, IgM-secreting B lymphocytes is 10-20 times lower than in earlier B-lineage cells expressing delta mRNA. We find that transcription of the mu + delta gene in IgM-secreting murine myeloma cells terminates within a region of 500-1000 nucleotides immediately following the mu membrane (mu m) polyadenylylation site. Transcription decreases only minimally through this region in murine cell lines representative of earlier stages in B-cell development. A DNA fragment containing the mu m polyadenylylation signal gives protein-DNA complexes with different mobilities in gel retardation assays with nuclear extracts from myeloma cells than with nuclear extracts from earlier B-lineage cells. However, using a recently developed "footprinting" procedure in which protein-DNA complexes resolved in gel retardation assays are subjected to nucleolytic cleavage while still in the polyacrylamide gel, we find that the DNA sequences protected by factors from the two cell types are indistinguishable. The factor-binding site on the DNA is located 5' of the mu m polyadenylylation signal AATAAA and includes the 15-nucleotide-long A + T-rich palindrome CTGTAAACAAATGTC. This type of palindromic binding site exhibits orientation-dependent activity consistent with the reported properties of polymerase II termination signals. This binding site is followed by two sets of directly repeated DNA sequences with different helical conformation as revealed by their reactivity with the chemical nuclease 1,10-phenanthroline-copper. The close proximity of these features to the signals for mu m mRNA processing may reflect a linkage of the processes of developmentally regulated mu m polyadenylylation and transcription termination.

Relation between intraoperative EMG values and final pedicle screw position as seen on CT images

Introduction: Intraoperative EMG based neurophysiological monitoring is increasingly used to assist pedicle screw insertion. We carried out a study comparing the final screw position in the pedicle measured on CT images in relation to its corresponding intraoperative muscle compound action potential (CMAP) values. Material and methods: A total of 189 screws were inserted in thoracolumbar spines of 31 patients during instrumented fusion under EMG control. An observer, blinded to the CMAP value, assessed the horizontal and vertical 'screw edge to pedicle edge' distance perpendicular to the longitudinal axis of the screw on reformatted CT reconstructions using OsiriX software. These distances were analysed with their corresponding CMAP values. Data from 62 thoracic and 127 lumbar screws were processed separately. Interobserver reliability of distance measurements was assessed. Results: No patient suffered neurological injury secondary to screw insertion. Distance measurements were reliable (paired t-test, P = 0.13/0.98 horizontal/vertical). Two screws had their position altered due to low CMAP values suggesting close proximity of nerve tissue. Seventy five percent of screws had CMAP results above 10mA and had an average distance of 0.35cm (SD 0.23) horizontally and 0.46cm (SD 0.26) vertically from the pedicle edge. Additional 12% had a distance from the edge of the pedicle less than 0mm indicating cortical breach but had CMAP values above 10mA. A poor correlation between CMAP values and screw position was found. Discussion: In this study CMAP values above 10mA indicated correct screw position in the majority of cases. The zone of 10-20mA CMAP carries highest risk of a misplaced screw despite high CMAP value (17% of screws this CMAP range). In order to improve accuracy of EMG predictive value further research is warranted including improvement of probing techniques.

PAP1 [poly(A) polymerase 1] homozygosity and hyperadenylation are major determinants of increased mRNA stability of CDR1 in azole-resistant clinical isolates of Candida albicans.

Using genetically matched azole-susceptible (AS) and azole-resistant (AR) clinical isolates of Candida albicans, we recently demonstrated that CDR1 overexpression in AR isolates is due to its enhanced transcriptional activation and mRNA stability. This study examines the molecular mechanisms underlying enhanced CDR1 mRNA stability in AR isolates. Mapping of the 3' untranslated region (3' UTR) of CDR1 revealed that it was rich in adenylate/uridylate (AU) elements, possessed heterogeneous polyadenylation sites, and had putative consensus sequences for RNA-binding proteins. Swapping of heterologous and chimeric lacZ-CDR1 3' UTR transcriptional reporter fusion constructs did not alter the reporter activity in AS and AR isolates, indicating that cis-acting sequences within the CDR1 3' UTR itself are not sufficient to confer the observed differential mRNA decay. Interestingly, the poly(A) tail of the CDR1 mRNA of AR isolates was approximately 35-50 % hyperadenylated as compared with AS isolates. C. albicans poly(A) polymerase (PAP1), responsible for mRNA adenylation, resides on chromosome 5 in close proximity to the mating type-like (MTL) locus. Two different PAP1 alleles, PAP1-a/PAP1-alpha, were recovered from AS (MTL-a/MTL-alpha), while a single type of PAP1 allele (PAP1-alpha) was recovered from AR isolates (MTL-alpha/MTL-alpha). Among the heterozygous deletions of PAP1-a (Deltapap1-a/PAP1-alpha) and PAP1-alpha (PAP1-a/Deltapap1-alpha), only the former led to relatively enhanced drug resistance, to polyadenylation and to transcript stability of CDR1 in the AS isolate. This suggests a dominant negative role of PAP1-a in CDR1 transcript polyadenylation and stability. Taken together, our study provides the first evidence, to our knowledge, that loss of heterozygosity at the PAP1 locus is linked to hyperadenylation and subsequent increased stability of CDR1 transcripts, thus contributing to enhanced drug resistance.

Does VAA popularity pay off ? : Smartvote users preferred candidates and their results in the 2007 Swiss federal elections

Voting is fundamental for democracy, however, this decisive democratic act requires quite an effort. Decision making at elections depends largely on the interest to gather information about candidates and parties, the effort to process the information at hand and the motivation to reach a vote choice. Especially in electoral systems with highly fragmented party systems and hundreds of candidates running for office, the process of decision making in the pre‐election sphere is highly demanding. In the age of information and communication technologies, new possibilities for gathering and processing such information are available. Voting Advice Applications (VAAs) provide guidance to voters prior to the act of voting and assist voters in choosing between different candidates and parties on the basis of issue congruence. Meanwhile widely used all over the world, scientific inquiry into the effect of such tools on electoral behavior is ongoing. This paper adds to the current debate by focusing on whether the popularity of candidates on the Swiss VAA smartvote eventually paid off at the 2007 Swiss federal elections and whether there is a direct link between the performance of a candidate on the tool and his or her electoral performance.

The Strength of Promissory Representation : What Makes MPs Change their Positions ?

The paper analyses the positional congruence between pre-election statements in the Swiss voting assistance application "smartvote" and post-election behaviour in the Swiss lower house between 2003 and 2009. For this purpose, we selected 34 smartvote questions which subsequently came up in parliament. Unlike previous studies which assessed the program-to-policy linkage of governments or party groups the paper examines the question at the level of individual MPs which seems appropriate for political systems which follow the idea of power dispersion. While the average rate of political congruence is at some 85 percent, a multivariate analysis detects the underlying factors which push or curb a candidate's propensity to change his or her mind once elections are over. The results show that positional changes are more likely if (1) MPs are freshmen, (2) individual voting behaviour is invisible to the public, (3) the vote is not about a party's core issue, (4) the MP belongs to a party which is located in the political centre, and (5) if the pre-election statement is in disagreement with the majority position of the legislative party group. The last-mentioned factor is paramount: the farer away a candidate's pre-election profile from his or her party is located, the weaker turns out to be the electoral link of promissory representation.

Ku-deficient yeast strains exhibit alternative states of silencing competence.

In Saccharomyces cerevisiae, efficient silencer function requires telomere proximity, i.e. compartments of the nucleoplasm enriched in silencing factors. Accordingly, silencers located far from telomeres function inefficiently. We show here that cells lacking yKu balance between two mitotically stable states of silencing competence. In one, a partial delocalization of telomeres and silencing factors throughout the nucleoplasm correlates with enhanced silencing at a non-telomeric locus, while in the other, telomeres retain their focal pattern of distribution and there is no repression at the non-telomeric locus, as observed in wild-type cells. The two states also differ in their level of residual telomeric silencing. These findings indicate the existence of a yKu-independent pathway of telomere clustering and Sir localization. Interestingly, this pathway appears to be under epigenetic control.

Une approche strategique du vote : à propos de « vote par appobation, vote par note »

Ce texte a pour ambition de revenir sur une procédure d'expérimentation destinée à tester l'impact du vote par approbation ainsi que du vote par note sur l'ampleur de ce qu'on a coutume d'appeler le vote utile. Les résultats de ces expériences, menées lors des élections présidentielles françaises de 2007 et de 2012, ont fait l'objet de deux articles publiés dans la Revue économique. Notre objectif est ici d'attirer l'attention du lecteur sur la conception implicite qui sous-tend ces expériences : le vote comme outil de dévoilement des préférences individuelles. Une telle orientation se fait au détriment d'une conception stratégique du vote, c'est-à-dire le vote comme processus de coordination. Or, il nous semble que le propre du vote utile est précisément de s'inscrire dans une dimension stratégique du vote, dimension que la procédure expérimentale mise en place tend à gommer en ne fournissant pas aux votants de repères informationnels relatifs aux choix des autres votants. On parlera à cet effet d'isolation informationnelle. This text has the ambition to return to an experimental procedure designed to test the impact of approval voting as well as evaluating voting on the scope of what is called in French vote utile (strategic voting). The results of these experiences, held during the 2007 and 2012 French presidential elections, have been the object of two papers published in the Revue économique. Our aim is to catch the attention of readers on the implicit conception inherent to these experiences: voting as a means to reveal individual preferences. Such a direction is taken at the cost of a strategic conception of voting, i.e. voting as a coordination process. Yet, it seems to us that the main characteristic of strategic voting is precisely to be strategic. The design of the experimental procedure tends to erase this dimension, by depriving the voters of information on other voter's choices. This is what we call informational isolation.

Morphological scoring of human pronuclear zygotes for prediction of pregnancy outcome.

BACKGROUND: As embryo selection is not allowed by law in Switzerland, we need a single early scoring system to identify zygotes with high implantation potential and to select zygotes for fresh transfer or cryopreservation. The underlying aim is to maximize the cumulated pregnancy rate while limiting the number of multiple pregnancies. METHODS: In all, 613 fresh and 617 frozen-thawed zygotes were scored for proximity, orientation and centring of the pronuclei, cytoplasmic halo, and number and polarization of the nucleolar precursor bodies. From these individual scores, a cumulated pronuclear score (CPNS) was calculated. Correlation between CPNS and implantation was examined and compared between fresh and frozen-thawed zygotes. The effect of freezing on CPNS was also investigated. RESULTS: CPNS was positively associated with embryo implantation in both fresh and frozen zygotes. With similar CPNS, frozen zygotes presented implantation rates as high as those of fresh zygotes. Nucleolar precursor bodies pattern and cytoplasmic halo appeared as the most important factors predictive of implantation for both types of zygotes, while pronuclei position was specifically relevant for frozen-thawed zygotes. Freezing induced an alteration of most zygote parameters, resulting in a significantly lower CPNS and a lower pregnancy rate. CONCLUSIONS: CPNS may be used as a single prognostic tool for implantation of both fresh and frozen-thawed zygotes. Lower CPNS values of frozen-thawed zygotes may also be indicative of freezing damage to zygotes. Successful implantation of frozen zygotes despite lower CPNS suggests that they may recover after thawing and in vitro culture.

Latitude gradients in melanoma incidence and mortality in the non-Maori population of New Zealand

The variation with latitude of incidence and mortality for cutaneous malignant melanoma (CMM) in the non-Maori population of New Zealand was assessed. For those aged 20 to 74 years, the effects of age, time period, birth-cohort, gender, and region (latitude), and some interactions between them were evaluated by log-linear regression methods. Increasing age-standardized incidence and mortality rates with increasing proximity to the equator were found for men and women. These latitude gradients were greater for males than females. The relative risk of melanoma in the most southern part of New Zealand (latitude 44 degrees S) compared with the most northern region (latitude 36 degrees S) was 0.63 (95 percent confidence interval [CI] = 0.60-0.67) for incidence and 0.76 (CI = 0.68-0.86) for mortality, both genders combined. The mean percentage change in CMM rates per degree of latitude for males was greater than those reported in other published studies. Differences between men and women in melanoma risk with latitude suggest that regional sun-behavior patterns or other risk factors may contribute to the latitude gradient observed.

What explains electoral turnout in Swiss municipalities?

What explains the higher electoral turnout in some of the Swiss municipalities? Since there are important differences as far as size, socio-economic structure, importance, political systems and the prevailing political culture are concerned, the Swiss municipalities offer a laboratory-like field of research. Using aggregate level data from our own surveys and from official sources covering the whole country this paper investigates the determinants of voting turnout at the local level. It comes to the following conclusion: The level of electoral turnout in Swiss municipalities depends to an important extent on institutional variables. If the executive is elected in a citizens' assembly there are considerably fewer people participating than in elections at the polls. PR also has a positive effect on turnout, whereas it cannot be shown that having a local parliament leads to higher turnout (and thus to increased interest in politics). Another important variable is the size of a municipality. In smaller municipalities turnout is consistently higher than in bigger ones. As for the importance of Catholicism for turnout, our study confirms the findings of Freitag (2005) at the cantonal level. The Catholic milieu has a positive impact on participation

Evidence evaluation in fingerprint comparison and automated fingerprint identification systems: modeling between finger variability

In the context of the investigation of the use of automated fingerprint identification systems (AFIS) for the evaluation of fingerprint evidence, the current study presents investigations into the variability of scores from an AFIS system when fingermarks from a known donor are compared to fingerprints that are not from the same source. The ultimate goal is to propose a model, based on likelihood ratios, which allows the evaluation of mark-to-print comparisons. In particular, this model, through its use of AFIS technology, benefits from the possibility of using a large amount of data, as well as from an already built-in proximity measure, the AFIS score. More precisely, the numerator of the LR is obtained from scores issued from comparisons between impressions from the same source and showing the same minutia configuration. The denominator of the LR is obtained by extracting scores from comparisons of the questioned mark with a database of non-matching sources. This paper focuses solely on the assignment of the denominator of the LR. We refer to it by the generic term of between-finger variability. The issues addressed in this paper in relation to between-finger variability are the required sample size, the influence of the finger number and general pattern, as well as that of the number of minutiae included and their configuration on a given finger. Results show that reliable estimation of between-finger variability is feasible with 10,000 scores. These scores should come from the appropriate finger number/general pattern combination as defined by the mark. Furthermore, strategies of obtaining between-finger variability when these elements cannot be conclusively seen on the mark (and its position with respect to other marks for finger number) have been presented. These results immediately allow case-by-case estimation of the between-finger variability in an operational setting.

Genome-wide analysis of SREBP1 activity around the clock reveals its combined dependency on nutrient and circadian signals.

In mammals, the circadian clock allows them to anticipate and adapt physiology around the 24 hours. Conversely, metabolism and food consumption regulate the internal clock, pointing the existence of an intricate relationship between nutrient state and circadian homeostasis that is far from being understood. The Sterol Regulatory Element Binding Protein 1 (SREBP1) is a key regulator of lipid homeostasis. Hepatic SREBP1 function is influenced by the nutrient-response cycle, but also by the circadian machinery. To systematically understand how the interplay of circadian clock and nutrient-driven rhythm regulates SREBP1 activity, we evaluated the genome-wide binding of SREBP1 to its targets throughout the day in C57BL/6 mice. The recruitment of SREBP1 to the DNA showed a highly circadian behaviour, with a maximum during the fed status. However, the temporal expression of SREBP1 targets was not always synchronized with its binding pattern. In particular, different expression phases were observed for SREBP1 target genes depending on their function, suggesting the involvement of other transcription factors in their regulation. Binding sites for Hepatocyte Nuclear Factor 4 (HNF4) were specifically enriched in the close proximity of SREBP1 peaks of genes, whose expression was shifted by about 8 hours with respect to SREBP1 binding. Thus, the cross-talk between hepatic HNF4 and SREBP1 may underlie the expression timing of this subgroup of SREBP1 targets. Interestingly, the proper temporal expression profile of these genes was dramatically changed in Bmal1-/- mice upon time-restricted feeding, for which a rhythmic, but slightly delayed, binding of SREBP1 was maintained. Collectively, our results show that besides the nutrient-driven regulation of SREBP1 nuclear translocation, a second layer of modulation of SREBP1 transcriptional activity, strongly dependent from the circadian clock, exists. This system allows us to fine tune the expression timing of SREBP1 target genes, thus helping to temporally separate the different physiological processes in which these genes are involved.

Angiogenesis in Wounds Treated by Microdeformational Wound Therapy.

BACKGROUND:: Mechanical forces play an important role in tissue neovascularization and are a constituent part of modern wound therapies. The mechanisms by which vacuum assisted closure (VAC) modulates wound angiogenesis are still largely unknown. OBJECTIVE:: To investigate how VAC treatment affects wound hypoxia and related profiles of angiogenic factors as well as to identify the anatomical characteristics of the resultant, newly formed vessels. METHODS:: Wound neovascularization was evaluated by morphometric analysis of CD31-stained wound cross-sections as well as by corrosion casting analysis. Wound hypoxia and mRNA expression of HIF-1α and associated angiogenic factors were evaluated by pimonidazole hydrochloride staining and quantitative reverse transcription-polymerase chain reaction (RT-PCR), respectively. Vascular endothelial growth factor (VEGF) protein levels were determined by western blot analysis. RESULTS:: VAC-treated wounds were characterized by the formation of elongated vessels aligned in parallel and consistent with physiologically function, compared to occlusive dressing control wounds that showed formation of tortuous, disoriented vessels. Moreover, VAC-treated wounds displayed a well-oxygenated wound bed, with hypoxia limited to the direct proximity of the VAC-foam interface, where higher VEGF levels were found. By contrast, occlusive dressing control wounds showed generalized hypoxia, with associated accumulation of HIF-1α and related angiogenic factors. CONCLUSIONS:: The combination of established gradients of hypoxia and VEGF expression along with mechanical forces exerted by VAC therapy was associated with the formation of more physiological blood vessels compared to occlusive dressing control wounds. These morphological changes are likely a necessary condition for better wound healing.

Factors influencing interprofessional practices of physiotherapists working in private settings with people with low back pain: a qualitative study

Purpose: Collaboration and interprofessional practices are highly valued in health systems everywhere, partly based on the rationale that they improve outcomes of care for people with complex health problems, such as low back pain. Research in the area of low back pain also supports the involvement of different health professionals in the interventions for people who present this condition. The aim of this studywas to identify factors influencing the interprofessional practices of physiotherapists working in private settings with people with low back pain. Relevance: Physiotherapists, like other health professionals, are encouraged to engage in interprofessional practices in their dailywork. However, to date, very little is known of their interprofessional practices, especially in private settings. Understanding physiotherapists' interprofessional practices and their influencing factors will notably advance knowledge relating to the organisation of physiotherapy services for people with low back pain. Participants: Participants in this study were 13 physiotherapists including 10 women and 3 men, having between 3 and 22 years of professional experience, and working in one of 10 regions of the Province of Quebec (Canada). In order to obtain maximal variation in the perspectives, participants were selected using a recruitment matrix including three criteria: duration of professional experience, work location, and physical proximity with other professionals. Methods: Thiswas a descriptive qualitative study using faceto- face semi-structured interviews as the main method of data collection. An interview guide was developed based on an evidence-derived frame of reference. Each interview lasted between 55 and 95 minutes and was transcribed verbatim. Analysis: Qualitative analyses took the form of content analysis, encompassing data coding and general thematic regrouping. NVivo version 8 was used to assist data organisation and analysis. Results: Multiple factors influencing the interprofessional practices of physiotherapists were identified. The main factors include the consulting person's health condition, the extent of knowledge on health professionals' roles and fields of practice, the proximity and availability of professional resources, as well as daily work schedules. Conclusions: Our findings highlight the influence of multiple factors on physiotherapists' interprofessional practices, including professional practice and organisational issues. However, further research on the interprofessional practices of physiotherapists is still required. Research priorities targeting the views of other health professionals, as well as those of services users, would enhance our comprehension of interprofessional practices of physiotherapists. Implications: This study provides new insights that improve our understanding of the interprofessional practices of physiotherapists working in private settings with people with low back pain, more specifically on the factors influencing these practices. Based on our findings, implementing changes such as improving current and future health professionals' knowledge of the fields and roles of other health professionals through training may contribute to positively influencing interprofessional practices. Keywords: Interprofessional practices; Private practice; Low back pain Funding acknowledgements: This research was supported in part by a B.E. Schnurr Memorial Fund Research Grant administered by the Physiotherapy Foundation of Canada, as well as from a clinical research partnership in physiotherapy between the Quebec Rehabilitation Research Network (REPAR) and the Ordre professionnel de la physiothérapie du Québec (OPPQ). KP received doctoral-level scholarships from the Canadian Institutes of Health Research (CIHR) and the Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST). CE Dionne is a FRSQ senior Research Scholar. Ethics approval: This project was approved by the ethics research committee of the Institut de réadaptation en déficience physique de Québec.