Role of prohormone convertases in pro-neuropeptide Y processing: coexpression and in vitro kinetic investigations.

Proneuropeptide Y (ProNPY) undergoes cleavage at a single dibasic site Lys38-Arg39 resulting in the formation of 1-39 amino acid NPY which is further processed successively by carboxypeptidase-like and peptidylglycine alpha-amidating monooxygenase enzymes. To investigate whether prohormone convertases are involved in ProNPY processing, a vaccinia virus derived expression system was used to coexpress recombinant ProNPY with each of the prohormone convertases PC1/3, PC2, furin, and PACE4 in Neuro2A and NIH 3T3 cell lines as regulated neuroendocrine and constitutive prototype cell lines, respectively. The analysis of processed products shows that only PC1/3 generates NPY in NIH 3T3 cells while both PC1/3 and PC2 are able to generate NPY in Neuro2A cells. The convertases furin and PACE4 are unable to process ProNPY in either cell line. Moreover, comparative in vitro cleavage of recombinant NPY precursor by the enzymes PC1/3, PC2 and furin shows that only PC1/3 and PC2 are involved in specific cleavage of the dibasic site. Kinetic studies demonstrate that PC1/3 cleaves ProNPY more efficiently than PC2. The main difference between the cleavage efficiency is observed in the Vmax values whereas no major difference is observed in Km values. In addition the cleavage by PC1/3 and PC2 of two peptides reproducing the dibasic cleavage site with different amino acid sequence lengths namely (20-49)-ProNPY and (28-43)-ProNPY was studied. These shortened ProNPY substrates, when recognized by the enzymes, are more efficiently cleaved than ProNPY itself. The shortest peptide is not cleaved by PC2 while it is by PC1/3. On the basis of these observations it is proposed, first, that the constitutive secreted NPY does not result from the cleavage carried out by ubiquitously expressed enzymes furin and PACE4; second, that PC1/3 and PC2 are not equipotent in the cleavage of ProNPY; and third, substrate peptide length might discriminate PC1/3 and PC2 processing activity.

Fracture rates of IPS Empress all-ceramic crowns: a systematic review.

Purpose: The aim of this study was to evaluate the clinical fracture rate of crowns fabricated with the pressable, leucite-reinforced ceramic IPS Empress, and relate the results to the type of tooth restored. Materials and Methods: The database SCOPUS was searched for clinical studies involving full-coverage crowns made of IPS Empress. To assess the fracture rate of the crowns in relation to the type of restored tooth and study, Poisson regression analysis was used. Results: Seven clinical studies were identified involving 1,487 adhesively luted crowns (mean observation time: 4.5 +/- 1.7 years) and 81 crowns cemented with zinc-phosphate cement (mean observation time: 1.6 +/- 0.8 years). Fifty-seven of the adhesively luted crowns fractured (3.8%). The majority of fractures (62%) occurred between the third and sixth year after placement. There was no significant influence regarding the test center on fracture rate, but the restored tooth type played a significant role. The hazard rate (per year) for crowns was estimated to be 5 in every 1,000 crowns for incisors, 7 in every 1,000 crowns for premolars, 12 in every 1,000 crowns for canines, and 16 in every 1,000 crowns for molars. One molar crown in the zinc-phosphate group fractured after 1.2 years. Conclusion: Adhesively luted IPS Empress crowns showed a low fracture rate for incisors and premolars and a somewhat higher rate for molars and canines. The sample size of the conventionally luted crowns was too small and the observation period too short to draw meaningful conclusions. Int J Prosthodont 2010;23:129-133.

Looking for factors involved in the light-dependent degradation of phytochrome A

SUMMARY : Phytochromes constitute a family of red/far-red photoreceptors regulating all the major transitions during the life cycle of plants. In Arabidopsis, five members: phyA,_ B, C, D and E, were identified. Phytochromes are synthesized in their inactive red-light absorbing form called Pr. Upon light absorbance they convert to the far-red light absorbing Pfr form. The Pfr form is the active conformer which converts back to the Pr form either rapidly upon far-red perception or in a slower process called dark reversion. ph~A represents an exception, in that it does not significantly dark-revert and two specific processes have been developed by the plants to decrease the amount of biologically active phyA. The first one is alight-dependent repression of the PHYA gene expression and the second one is alight-dependent degradation of the phyA protein. The latter is the most efficient process to rapidly decrease the level of active phyA. The ability of plants to regulate the amount of active phyA is critical in a far-red rich environment, a situation observed under a canopy. In these conditions, phyA is essential to induce the germination and the deetiolation of the young seedling. Later in the development the ability of phyA to repress growth counteracts the shade avoidance response. Therefore decreasing the amount of phyA allows stem growth and to compete with neighbours for the light. In this thesis, I investigate the light-dependent degradation of phyA. I developed a reverse genetic approach based on the systematic analysis of the light-dependent accumulation of phyA in the different cullin mutant cull, cul3a; cul3b and cul4. This analysis allowed me to show that CUL1 and CUL3A-based E3 ligase complexes are involved in the regulation of phyA degradation. Surprisingly, our results also demonstrate that cu14 is not affected in the degradation of phyA whereas constitutive Photomorphogenic 1 (COP1) a subunit of one CUL4based E3 complex was reported to be involved. Further investigations showed that the phenotype of cop1 is conditional, the mutant being defective in phyA degradation only in the presence of metabolisable sugars. I also showed that phyA is degraded by a proteasome-dependent mechanism both in the cytoplasm and in the nucleus using mutants and transgenic lines affected in the localization of phyA. Interestingly, I observed that phyA degradation was faster in the nucleus than in the cytosol and that rapid degradation of Pr also occurred in the nucleus suggesting that cytosolic accumulation of phyA in the dark is a way to regulate its proteolysis. Finally, we identify a short region similar to a PEST sequence required for phyA stability and we developed a unbiased genetic screen to identify new components involved in the regulation of the light-dependent degradation of phyA. The significance of these results are discussed. RESUME : Les phytochromes (phy) constituent une famille de photorécepteurs absorbant la lumière rouge et rouge lointaine et régulant toutes les étapes de transitions majeures dans la vie des plantes. Chez Arabidopsis, cinq membres : phyA, B, C, D et E ont été identifiés. Les phytochromes sont synthétisés sous une forme inactive appelée Pr absorbant la lumière rouge. Après perception de lumière ils passent sous une forme active Pfr absorbant dans le rouge lointain. La forme Pfr peut retourner sous la forme Pr après absorption de lumiëre rouge lointaine ou dans un processus lent appelé «réversion à l'obscurité ». phyA représente une exception à cette règle car il ne retoune pas significativement sous sa forme inactive dans le noir. Deux processus spécifiques ont donc été développés pour diminuer le taux de phyA actif. Le premier consiste en la répression du gène PHYA en condition de lumière et le second en une dégradation induite par la lumière de la protéine phyA. Ce dernier processus est le plus efficace pour diminuer rapidement le niveau de phyA. La capacité des plantes à réguler le taux de phyA actifs est critique dans un environnement riche en lumière rouge lointaine, une situation observée sous une canopée. Sous une canopée, phyA est essentiel pour induire la germination et la dé-étiolation de la jeune pousse. Plus tard dans le développement la capacité de phyA de réprimer la croissance freine la «réponse à l'évitement de l'ombre ». Par conséquent diminuer le taux de phyA permet la croissance de la tige et donc de rentrer en compétition pour la lumière avec les plantes avoisinantes. Dans cette thèse, j'ai étudié la dégradation de phyA. J'ai développé une approche génétique inverse basée sur l'analyse systématique de l'accumulation de phyA en condition de lumière dans les différents mutants cullin, cul1, cul3a, cul3b et cul4. Ces analyses nous ont permis d'identifier qu'un complexe E3 ligase CUL1 et un complexe E3 ligase CUL3A sont impliqués dans la régulation de la dégradation de phyA. Mes résultats démontrent aussi que le mutant cul4 n'est pas affecté dans la dégradation de phyA alors que Çonstitutive Photomorphogenic 1 (COPI) une sous unité d'un complexe CUL4 à été identifier dans la régulation de cette dégradation. Des analyses supplémentaires suggèrent que l'effet de la mutation cop1 est dépendante dë la présence de sucres métabolisables. J'ai aussi montré que phyA est dégradé dans le noyau et dans le cytoplasme par un mécanisme dépendant du protéasome et que la dégradation dans le.noyau est non seulement aspécifique de la forme Pr ou Pfr mais aussi est plus rapide que dans le cytoplasme. Ceci suggère que l'accumulation de phyA dans le cytoplasme permet son accumulation à des niveaux élevés à l'obscurité. Enfin j'ai identifié une région similaire à un motif PEST requise pour la stabilité de phyA et j'ai aussi développé un criblage génétique non biaisé pour identifier de nouveaux composants impliqués dans la régulation de la dégradation de phyA. L'importance de ces résultats est discutée dans le dernier chapitre de cette thèse.

Supervised injection services : what has been demonstrated? A systematic literature review

BACKGROUND: Supervised injection services (SISs) have been developed to promote safer drug injection practices, enhance health-related behaviors among people who inject drugs (PWID), and connect PWID with external health and social services. Nevertheless, SISs have also been accused of fostering drug use and drug trafficking. AIMS: To systematically collect and synthesize the currently available evidence regarding SIS-induced benefits and harm. METHODS: A systematic review was performed via the PubMed, Web of Science, and ScienceDirect databases using the keyword algorithm [("supervised" or "safer") and ("injection" or "injecting" or "shooting" or "consumption") and ("facility" or "facilities" or "room" or "gallery" or "centre" or "site")]. RESULTS: Seventy-five relevant articles were found. All studies converged to find that SISs were efficacious in attracting the most marginalized PWID, promoting safer injection conditions, enhancing access to primary health care, and reducing the overdose frequency. SISs were not found to increase drug injecting, drug trafficking or crime in the surrounding environments. SISs were found to be associated with reduced levels of public drug injections and dropped syringes. Of the articles, 85% originated from Vancouver or Sydney. CONCLUSION: SISs have largely fulfilled their initial objectives without enhancing drug use or drug trafficking. Almost all of the studies found in this review were performed in Canada or Australia, whereas the majority of SISs are located in Europe. The implementation of new SISs in places with high rates of injection drug use and associated harms appears to be supported by evidence.

The role of focal therapy in the management of localised prostate cancer: a systematic review.

CONTEXT: The incidence of localised prostate cancer is increasing worldwide. In light of recent evidence, current, radical, whole-gland treatments for organ-confined disease have being questioned with respect to their side effects, cancer control, and cost. Focal therapy may be an effective alternative strategy. OBJECTIVE: To systematically review the existing literature on baseline characteristics of the target population; preoperative evaluation to localise disease; and perioperative, functional, and disease control outcomes following focal therapy. EVIDENCE ACQUISITION: Medline (through PubMed), Embase, Web of Science, and Cochrane Review databases were searched from inception to 31 October 2012. In addition, registered but not yet published trials were retrieved. Studies evaluating tissue-preserving therapies in men with biopsy-proven prostate cancer in the primary or salvage setting were included. EVIDENCE SYNTHESIS: A total of 2350 cases were treated to date across 30 studies. Most studies were retrospective with variable standards of reporting, although there was an increasing number of prospective registered trials. Focal therapy was mainly delivered to men with low and intermediate disease, although some high-risk cases were treated that had known, unilateral, significant cancer. In most of the cases, biopsy findings were correlated to specific preoperative imaging, such as multiparametric magnetic resonance imaging or Doppler ultrasound to determine eligibility. Follow-up varied between 0 and 11.1 yr. In treatment-naïve prostates, pad-free continence ranged from 95% to 100%, erectile function ranged from 54% to 100%, and absence of clinically significant cancer ranged from 83% to 100%. In focal salvage cases for radiotherapy failure, the same outcomes were achieved in 87.2-100%, 29-40%, and 92% of cases, respectively. Biochemical disease-free survival was reported using a number of definitions that were not validated in the focal-therapy setting. CONCLUSIONS: Our systematic review highlights that, when focal therapy is delivered with intention to treat, the perioperative, functional, and disease control outcomes are encouraging within a short- to medium-term follow-up. Focal therapy is a strategy by which the overtreatment burden of the current prostate cancer pathway could be reduced, but robust comparative effectiveness studies are now required.

Potential of kite aerial photography for peatland investigations with examples from Estonia

Tiivistelmä: Leijailmakuvausmenetelmän käyttömahdollisuudet soiden kartoituksessa - esimerkkejä Viron soilta

Résumés actualisés de l'évaluation systématique de l'efficacité d'interventions médicales. [Up-to-date résumés of the systematic evaluation of efficacy of medical interventions]

La Cochrane Library (www.thecochranelibrary.com) est une bibliothèque en ligne répertoriant à ce jour plus de 3000 revues systématiques. Ces revues systématiques sont issues de l'activité continue de plus de 50 groupes de revues de la Collaboration Cochrane (www.cochrane.org ), une organisation à laquelle participent plus de 20 000 personnes dans le monde entier et dont le financement est indépendant de sources pouvant créer un conflit d'intérêt. Le public cible est constitué par les professionnels de la santé, les décideurs en matière sanitaire et le public (patients, consommateurs). En sus de la production et de la diffusion de revues systématiques, la Collaboration Cochrane propose également des activités de formation aux méthodes de la médecine factuelle et des revues systématiques. En Francophonie, de telles formations sont proposées par des partenaires du Réseau francophone Cochrane (www.res_franco.cochrane.org ), dont la coordination est assurée depuis Lausanne par une petite équipe basée à l'Institut universitaire de médecine sociale et préventive (IUMSP). [Extrait]

Structural investigations into the interaction of hemoglobin and part structures with bacterial endotoxins.

An understanding of details of the interaction mechanisms of bacterial endotoxins (lipopolysaccharide, LPS) with the oxygen transport protein hemoglobin is still lacking, despite its high biological relevance. Here, a biophysical investigation into the endotoxin:hemoglobin interaction is presented which comprises the use of various rough mutant LPS as well as free lipid A; in addition to the complete hemoglobin molecule from fetal sheep extract, also the partial structure alpha-chain and the heme-free sample are studied. The investigations comprise the determination of the gel-to-liquid crystalline phase behaviour of the acyl chains of LPS, the ultrastructure (type of aggregate structure and morphology) of the endotoxins, and the incorporation of the hemoglobins into artificial immune cell membranes and into LPS. Our data suggest a model for the interaction between Hb and LPS in which hemoglobins do not react strongly with the hydrophilic or with the hydrophobic moiety of LPS, but with the complete endotoxin aggregate. Hb is able to incorporate into LPS with the longitudinal direction parallel to the lipid A double-layer. Although this does not lead to a strong disturbance of the LPS acyl chain packing, the change of the curvature leads to a slightly conical molecular shape with a change of the three-dimensional arrangement from unilamellar into cubic LPS aggregates. Our previous results show that cubic LPS structures exhibit strong endotoxic activity. The property of Hb on the physical state of LPS described here may explain the observation of an increase in LPS-mediating endotoxicity due to the action of Hb.

Biological embedding of early-life exposures and disease risk in humans : a role for DNA methylation

BACKGROUND: Following wider acceptance of 'the thrifty phenotype' hypothesis and the convincing evidence that early-life exposures can influence adult health even decades after the exposure, much interest has been placed on the mechanisms through which early-life exposures become biologically embedded. MATERIALS AND METHODS: In this review, we summarize the current literature regarding biological embedding of early-life experiences. To this end, we conducted a literature search to identify studies investigating early-life exposures in relation to DNA methylation changes. In addition, we summarize the challenges faced in investigations of epigenetic effects, stemming from the peculiarities of this emergent and complex field. A proper systematic review and meta-analyses were not feasible given the nature of the evidence. RESULTS: We identified seven studies on early-life socio-economic circumstances, 10 studies on childhood obesity and six studies on early-life nutrition all relating to DNA methylation changes that met the stipulated inclusion criteria. The pool of evidence gathered, albeit small, favours a role of epigenetics and DNA methylation in biological embedding, but replication of findings, multiple comparison corrections, publication bias and causality are concerns remaining to be addressed in future investigations. CONCLUSIONS: Based on these results, we hypothesize that epigenetics, in particular DNA methylation, is a plausible mechanism through which early-life exposures are biologically embedded. This review describes the current status of the field and acts as a stepping stone for future, better designed investigations on how early-life exposures might become biologically embedded through epigenetic effects.

Epilepsy surgery in children and adults.

SUMMARY: Epilepsy surgery is the most effective way to control seizures in patients with drug-resistant focal epilepsy, often leading to improvements in cognition, behaviour, and quality of life. Risks of serious adverse events and deterioration of clinical status can be minimised in carefully selected patients. Accordingly, guidelines recommend earlier and more systematic assessment of patients' eligibility for surgery than is seen at present. The effectiveness of surgical treatment depends on epilepsy type, underlying pathology, and accurate localisation of the epileptogenic brain region by various clinical, neuroimaging, and neurophysiological investigations. Substantial progress has been made in the methods of presurgical assessment, particularly in patients with normal features on MRI, but evidence is scarce for the indication and effect of most presurgical investigations, with no biomarker precisely delineating the epileptogenic zone. A priority for the development of epilepsy surgery is the generation of high-level evidence to promote the harmonisation and dissemination of best practices.

Role of hepatitis C virus genotype 3 in liver fibrosis progression : a systematic review and meta-analysis ; et, Impact of nurse vaccination program on hepatitis B immunity in a Swiss HIV clinic

Rôle du génotype 3 du virus de l'hépatite C dans la progression de la fibrose hépatique, une revue systématique avec méta-analyse. On estime à 170 millions le nombre de personnes atteintes d'hépatite C chronique dans le monde. La principale conséquence de cette maladie est la fibrose du foie, qui évolue plus ou moins rapidement, pour aboutir au développement d'une cirrhose et/ou d'un hépatocarcinome. Certains des facteurs accélérateurs de la fibrose, comme l'âge avancé au moment de l'infection, le sexe masculin, la consommation d'alcool, sont bien connus. On a longtemps considéré que les six différents génotypes viraux n'influençaient pas la progression de la fibrose. Des études récentes ont cependant suggéré que certains génotypes, en particulier ie génotype 3, pouvaient entraîner une fibrose plus rapide. Le but de ce travail de thèse était de déterminer à l'aide d'une méta-analyse le rôle du génotype viral dans la progression de la fibrose dans l'infection chronique au virus de l'hépatite C. Les études ont été sélectionnées dans la littérature médicale à partir d'une série de mots-clés. Le degré de fibrose a été estimé par biopsie, en utilisant le score Metavir. Deux types d'études ont décrits de manière différente la durée d'infection. Les premières ont calculé la progression de la fibrose depuis le moment estimée de l'infection (« études avec une biopsie »), les secondes ont exprimés cette durée comme étant l'intervalle entre deux biopsies (« études avec deux biopsies »). L'analyse a permis d'identifier 8 études avec une biopsie pour un collectif total de 3182 patients ainsi que 8 études avec deux biopsies pour un collectif de 896 patients. Dans une méta-analyse de type « random effect », le rapport de cote pour l'association du génotype 3 avec une fibrose accélérée est de 1.52 (95% IC 1.12-2.07, p=0.007) pour les études à une biopsie. Pour les études à deux biopsies, le rapport de cote pour cette association est de 1.37 (95% IC 0.87-2.17, P=0.17). Cette étude montre que les patients avec une hépatite C chronique due au génotype 3 ont une progression de fibrose plus rapide que ceux qui sont infectés par les autres génotypes. Alors que la méta-analyse des études avec une biopsie est clairement significative, celle des études avec deux biopsies est au-dessous du seuil de significativité. Les études à deux biopsies peuvent être limitées par plusieurs facteurs, comprenant un « biais d'indication » (seuls les patients évoluant rapidement vers la cirrhose ont plus de risque d'avoir une deuxième biopsie), une durée d'observation très courte (5 années comparée à 13 années pour les études à 2 biopsies), et un nombre de patient limité (896 pour le études à 2 biopsies comparé à 3182 pour les études à 1 biopsie). Impact d'un programme de vaccination sur l'immunité contre l'hépatite Β dans une clinique suisse du VIH Le virus de l'hépatite Β cause une infection aigûe dont la symptomatologie varie d'une présentation subclinique à une progression fulminante. Dans une minorité de cas, l'infection aigiie est suivie d'une infection chronique pouvant évoluer vers une cirrhose hépatique et/ou un hépatocarcinome. La prévalence de l'hépatite Β aiguë et chronique chez les personnes vivant avec le virus d'immunodéficience humaine (VIH) est supérieure à celle de la population générale. Par ailleurs la co-infection avec le virus du VIH entraine une progression plus rapide de l'hépatite B. Dès lors, l'immunité pour le virus de l'hépatite Β représente un facteur primordial de prévention dans la population infectée par le virus de l'HIV. Bien que l'administration d'un vaccin contre l'hépatite Β soit particulièrement recommandée chez tous les individus infectés par le VIH, la couverture vaccinale dans cette population est souvent insuffisante. Le but de cette étude était de déterminer l'état d'immunisation contre le virus de l'hépatite Β dans la population infectée par le VIH de la cohorte Suisse HIV et d'analyser l'efficacité d'un programme de vaccination administré par le personnel soignant. L'immunité avant et après intervention dans notre centre a été comparée aux autres centres de la cohorte HIV en Suisse. L'immunité pour le centre d'intervention a passé de 32% avant intervention à 76% après intervention alors que pour les autres centres, l'immunité n'a progressé que de 33% à 39% dans le même laps de temps (n=2712, P=0.001). Cette étude montre qu'un contrôle systématique de l'immunité par du personnel soignant augmente de manière significative l'immunité pour le vaccin de l'hépatite Β dans la population HIV.

Artemisia (Asteraceae): Understanding its evolution using cytogenetic and molecular systematic tools, with emphasis on subgenus Dracunculus

The genus Artemisia is one of the largest of the Asteraceae family, with more than 500 species. It is widely distributed mainly across the Northern Hemisphere, being profusely represented in the Old World, with a great centre of diversification in Asia, and also reaching the New World. The evolution of this genus has been deeply studied using different approaches, and polyploidy has been found to perform an important role leading to speciation processes. Karyological, molecular cytogenetic and phylogenetic data have been compiled in the present review to provide a genomic characterization throughout some complexes within the genus.

Incidence of anatomical variations and disease of the maxillary sinuses as identified by cone beam computed tomography: a systematic review.

PURPOSE: To analyze available evidence on the incidence of anatomical variations or disease of the maxillary sinuses as identified by cone beam computed tomography (CBCT) in dentistry. MATERIALS AND METHODS: A focused question was developed to search the electronic databases MEDLINE, EMBASE, the Cochrane Oral Health Group Trials Register, and CENTRAL and identify all relevant papers published between 1980 and January 19, 2013. Unpublished literature at ClinicalTrials.gov, in the National Research Register, and in the Pro-Quest Dissertation Abstracts and Thesis database was also included. Studies were included irrespective of language. These results were supplemented by hand and gray literature searches. RESULTS: Twenty-two studies were identified. Twenty were retrospective cohort studies, one was a prospective cohort study, and one was a case control study. The main indication for CBCT was dental implant treatment planning, and the majority of studies used a small field of view for imaging. The most common anatomical variations included increased thickness of the sinus membrane, the presence of sinus septa, and pneumatization. Reported sinus disease frequency varied widely, ranging from 14.3% to 82%. There was a wide range in the reported prevalence of mucosal thickening related to apical pathology, the degree of lumenal opacification, features of sinusitis, and the presence of retention cysts and polyps. More pathologic findings in the maxillary sinus were reported in men than in women, and the medial wall and sinus floor were most frequently affected. CONCLUSION: CBCT is used primarily to evaluate bony anatomy and to screen for overt pathology of the maxillary sinuses prior to dental implant treatment. Differences in the classification of mucosal findings are problematic in the consistent and valid assessment of health and disease of the maxillary sinus.