Severe Tricuspid Valve Endocarditis Related to Tunneled Catheters in Chronic Hemodialysis Patients: When Should the Catheter be Removed?

Introduction: Hemodialysis (HD) patients are predisposed to infective endocarditis (IE) mainly due to repeated manipulation of the vascular access. However, catheter seeding and IE may also result from a distant infection site.Case series: A diabetic patient who was maintained on regular HD through a permanent catheter in the right internal jugular vein presented with septicemia of urinary origin due to Pseudomonas aeruginosa. He was treated with injectable antibiotics for 15 days. Few days after the end of the treatment period he presented with inflammation of the catheter exit site. Blood cultures revealed Pseudomonas aeruginosa and echocardiography showed a large vegetation on the tricuspid valve, confirming the diagnosis of IE. The patient improved after catheter removal and treatment with ceftazidime, vancomycin and amikacin. Another patient who was maintained on chronic HD through a tunneled catheter in the right internal jugular vein presented with a limited infection in the sub-cutaneous tunnel of the catheter that improved after treatment with injectable antibiotics. Two months later, he presented with severe sepsis without signs of local infection of the catheter. Chest radiography showed right sided infiltrates. Injectable antibiotic therapy was given without improvement. Blood cultures were negative but echocardiography showed a large tricuspid valve vegetation. Antibiotic regimen was modified to include vancomycin, amikacin and ceftazidime and the catheter was removed. Unfortunately, the patient died two days after diagnosing IE.Conclusion: catheter seeding and IE may be a consequence of sepsis originating away from the HD catheter site. Tunneled catheters may need to be pre-emptively removed in such situations to prevent serious IE.Keywords: Hemodialysis; Infective Endocarditis; Tricuspid Valv

Évaluation des compétences pratiques en fin de deuxième cycle des études médicales : exemple du drainage du bas appareil urinaire

IntroductionLe drainage vésical peut, mal pratiqué, être iatrogène en se compliquant notamment d’infections et de traumatismes de l’appareil urinaire. Cette étude a pour objectif de déterminer la capacité des étudiants en médecine de fin de deuxième cycle à pratiquer les différents moyens de drainage des urines. Matériel et méthodes Entre janvier et mars 2007, un questionnaire d’autoévaluation des compétences de drainage urinaire a été envoyé par mail à un échantillon représentatif d’étudiants en médecine en dernière année d’externat, soit deux mois avant l’épreuve de l’examen national classant. Résultats Deux cent soixante-dix-sept réponses ont été reçues et analysées. Soixante-douze étudiants (26 %) jugeaient qu’ils maîtrisaient le cathétérisme urétrovésical chez l’homme et 106 étudiants (38,3 %) chez la femme à la fin de leur externat. Soixante et onze étudiants sur les 277 (25,5 %) avaient effectué un stage en urologie au cours de leur cursus. Parmi eux, 53,5 % estimaient acquis le sondage à demeure (SAD) chez l’homme (p < 0,001) et 39 (54,9 %) chez la femme (p < 0,001). Soixante-treize étudiants (26,4 %) estimaient qu’ils maîtrisaient le sondage minute d’une femme ou d’un homme et un seul considérait la pose de cathéter sus-pubien comme acquis. Conclusion L’apprentissage des gestes de drainage urinaire est enseigné de façon inappropriée au cours des études médicales puisque de jeunes médecins se sentent incapables de les reproduire au terme de leur externat. Cela est critiquable, car le sondage doit pouvoir être réalisé par tous médecins non urologues dans leur pratique quotidienne, notamment en terrain hospitalier. Cette étude doit mener à une réflexion sur l’amélioration de l’enseignement des gestes pratiques médicaux essentiels pendant l’externat

Evidence-based medicine et étudiants en médecine français : état des lieux

IntroductionL’Evidence-Based Medicine (EBM) est indispensable à l’exercice de la médecine. Notre objectif était de connaître quel en était son niveau de connaissance par les étudiants français. Matériel et Méthodes Entre avril et mai 2008, un questionnaire a été envoyé par courriel à 900 étudiants en dernière année du deuxième cycle des études médicales participant à des conférences publiques ou privées d’internat. Résultats Sur les 327 réponses, 297 (91 %), 94 (29 %) et 85 (26 %) étudiants déclaraient savoir lire, écrire et parler l’anglais médical. Quatre-vingt-dix étudiants (28 %) lisaient un article d’une revue médicale française, une fois par mois et 43 (13 %) lisaient un article d’une revue médicale internationale une fois par mois. Trois cent onze (95 %) connaissaient les bases de recherche médicale sur Internet et 219 (67 %) les utilisaient. Vingt-quatre (7 %) avaient déjà participé à la rédaction d’un article médical, sept (2 %) avait été co-auteurs. Deux cent soixante-douze (83 %) avait réalisé une présentation orale lors d’un staff médical et trois (1 %) lors d’un congrès. Enfin, 237 (73 %) comprenaient l’intérêt de l’épreuve d’analyse critique d’article à l’examen national classant (ECN) et 70 (21 %) pensaient y être préparés. Conclusion L’insuffisance de l’apprentissage de l’EBM est une des limites du système de formation français. L’introduction de la lecture critique d’article (LCA) à l’ECN est un début de réponse concret à ce problème

Spectroscopic Investigation of the Effect of Microstructure and Energetic Offset on the Nature of Interfacial Charge Transfer States in Polymer: Fullerene Blends

Despite performance improvements of organic photovoltaics, the mechanism of photoinduced electron-hole separation at organic donor-acceptor interfaces remains poorly understood. Inconclusive experimental and theoretical results have produced contradictory models for electron-hole separation in which the role of interfacial charge-transfer (CT) states is unclear, with one model identifying them as limiting separation and another as readily dissociating. Here, polymer-fullerene blends with contrasting photocurrent properties and enthalpic offsets driving separation were studied. By modifying composition, film structures were varied from consisting of molecularly mixed polymer-fullerene domains to consisting of both molecularly mixed and fullerene domains. Transient absorption spectroscopy revealed that CT state dissociation generating separated electron-hole pairs is only efficient in the high energy offset blend with fullerene domains. In all other blends (with low offset or predominantly molecularly mixed domains), nanosecond geminate electron-hole recombination is observed revealing the importance of spatially localized electron-hole pairs (bound CT states) in the electron-hole dynamics. A two-dimensional lattice exciton model was used to simulate the excited state spectrum of a model system as a function of microstructure and energy offset. The results could reproduce the main features of experimental electroluminescence spectra indicating that electron-hole pairs become less bound and more spatially separated upon increasing energy offset and fullerene domain density. Differences between electroluminescence and photoluminescence spectra could be explained by CT photoluminescence being dominated by more-bound states, reflecting geminate recombination processes, while CT electroluminescence preferentially probes less-bound CT states that escape geminate recombination. These results suggest that apparently contradictory studies on electron-hole separation can be explained by the presence of both bound and unbound CT states in the same film, as a result of a range of interface structures

Fatty acid profile in peri-prostatic adipose tissue and prostate cancer aggressiveness in African-Caribbean and Caucasian patients

BACKGROUND: Genetic and nutritional factors have been linked to the risk of aggressive prostate cancer (PCa). The fatty acid (FA) composition of peri-prostatic adipose tissue (PPAT), which reflects the past FA intake, is potentially involved in PCa progression. We analysed the FA composition of PPAT, in correlation with the ethno-geographical origin of the patients and markers of tumour aggressiveness. METHODS: From a cohort of 1000 men treated for PCa by radical prostatectomy, FA composition of PPAT was analysed in 156 patients (106 Caucasians and 50 African-Caribbeans), 78 with an indolent tumour (ISUP group 1 + pT2 + PSA <10 ng/mL) and 78 with an aggressive tumour (ISUP group 4-5 + pT3). The effect of FA extracted from PPAT on in-vitro migration of PCa cells DU145 was studied in 72 patients, 36 Caucasians, and 36 African-Caribbeans. RESULTS: FA composition differed according to the ethno-geographical origin. Linoleic acid, an essential n-6 FA, was 2-fold higher in African-Caribbeans compared with Caucasian patients, regardless of disease aggressiveness. In African-Caribbeans, the FA profile associated with PCa aggressiveness was characterised by low level of linoleic acid along with high levels of saturates. In Caucasians, a weak and negative association was observed between eicosapentaenoic acid level (an n-3 FA) and disease aggressiveness. In-vitro migration of PCa cells using PPAT from African-Caribbean patients was associated with lower content of linoleic acid. CONCLUSION: These results highlight an important ethno-geographical variation of PPAT, in both their FA content and association with tumour aggressiveness

Enseignement et perception de l’urologie à la fin du deuxième cycle des études médicales : état des lieux

Objectifs Déterminer la perception de l’urologie par les étudiants en fin de deuxième cycle des études médicales (DCEM) et connaître leurs supports d’enseignement. Matériel et méthodes Un auto-questionnaire a été diffusé par internet à 1600 étudiants de 16 facultés au cours de leur dernier semestre de DCEM. Résultats Au total, 590 réponses ont été reçues (36,8 %). Dans notre population, 70,2 % des étudiants étaient des femmes. Parmi eux, 24,1 % avaient fait un stage en urologie. L’urologie était considérée comme une discipline médicale, chirurgicale et médicochirurgicale, respectivement par 3,7 %, 37,8 % et 58 % d’entre eux. L’urologie était considérée comme une discipline très importante, importante, peu importante et pas importante par 5,1 %, 54,4 %, 37,5 % et 2,4 % d’entre eux. Les supports d’enseignement les plus utilisés pour préparer l’examen national classant (ENC) étaient les polycopiés d’internat (45,3 %), les conférences d’internat (43,7 %), le polycopié national du collège d’Urologie (38,6 %) et les cours dispensés à la faculté (32 %). Les items d’urologie les mieux assimilés étaient les pathologies lithiasiques (86,3 %), les troubles urinaires du bas appareil (76,3 %) et les cancers urologiques (56,7 %). À l’inverse, seulement 34,7 % et 28 % considéraient leurs connaissances suffisantes sur la dysfonction érectile et la transplantation rénale. Enfin, 7,5 % exprimaient le souhait de devenir urologue. La réalisation d’un stage en urologie était associée au sentiment d’avoir acquis les connaissances pour débuter l’internat (p < 0,001) et au souhait d’être urologue (p < 0,001). Conclusion Contre toute attente, l’urologie était considérée comme une discipline médicochirurgicale importante par la moitié des étudiants en fin de DCEM malgré le faible nombre d’items dédiés à l’urologie dans le programme de l’ENC. Un tiers d’entre eux utilisaient le polycopié national du collège d’Urologie pour préparer l’ENC et un quart avait réalisé un stage en urologie

Standardization of definitions in focal therapy of prostate cancer: report from a Delphi consensus project

Purpose: To reach standardized terminology in focal therapy (FT) for prostate cancer (PCa). Methods: A four-stage modified Delphi consensus project was undertaken among a panel of international experts in the field of FT for PCa. Data on terminology in FT was collected from the panel by three rounds of online questionnaires. During a face-to-face meeting on June 21, 2015, attended by 38 experts, all data from the online rounds were reviewed and recommendations for definitions were formulated. Results: Consensus was attained on 23 of 27 topics; Targeted FT was defined as a lesion-based treatment strategy, treating all identified significant cancer foci; FT was generically defined as an anatomy-based (zonal) treatment strategy. Treatment failure due to the ablative energy inadequately destroying treated tissue is defined as ablation failure. In targeting failure the energy is not adequately applied to the tumor spatially and selection failure occurs when a patient was wrongfully selected for FT. No definition of biochemical recurrence can be recommended based on the current data. Important definitions for outcome measures are potency (minimum IIEF-5 score of 21), incontinence (new need for pads or leakage) and deterioration in urinary function (increase in IPSS >5 points). No agreement on the best quality of life tool was established, but UCLA-EPIC and EORTC-QLQ-30 were most commonly supported by the experts. A complete overview of statements is presented in the text. Conclusion: Focal therapy is an emerging field of PCa therapeutics. Standardization of definitions helps to create comparable research results and facilitate clear communication in clinical practice

Natural resource exploitation in Western Sahara: new research directions

The authors wish to thank the Leverhulme Trust (through their Early Career scheme) and the Spanish Ministry of Economy, Industry and Competitivity, (CSO2017-86986-P, AEI/FEDER, UE) for funding this research. We would also like to thank Patricia Lalonde for her translations and editorial work, as well as all participants of the 'Analysis of the Management and Exploitation of Natural Resources in Situations of Conflict: The Case of Western Sahara' project (funded by the aforementioned ministry), for their constructive comments on earlier iterations of this paper.This review article provides an overview of research to date with an explicit focus on natural resource exploitation in Western Sahara. It integrates findings from various perspectives and disciplines, and synthesises the research done with a view to revealing gaps and, therefore, potential new research directions. As the issue of natural resource exploitation in Western Sahara has been conceptualised in very different ways and from the perspectives of a variety of disciplines, the authors have opted for a semi-systematic review of the work done encompassing academic, non-academic, and activist backgrounds.Leverhulme TrustSpanish Ministry of Economy, Industry and Competitivity (AEI/FEDER, UE) CSO2017-86986-

MicroRNA-96 Directly Inhibits γ-Globin Expression in Human Erythropoiesis

Fetal hemoglobin, HbF (α2γ2), is the main hemoglobin synthesized up to birth, but it subsequently declines and adult hemoglobin, HbA (α2β2), becomes predominant. Several studies have indicated that expression of the HbF subunit γ-globin might be regulated post-transcriptionally. This could be confered by ∼22-nucleotide long microRNAs that associate with argonaute proteins to specifically target γ-globin mRNAs and inhibit protein expression. Indeed, applying immunopurifications, we found that γ-globin mRNA was associated with argonaute 2 isolated from reticulocytes that contain low levels of HbF (<1%), whereas association was significantly lower in reticulocytes with high levels of HbF (90%). Comparing microRNA expression in reticulocytes from cord blood and adult blood, we identified several miRNAs that were preferentially expressed in adults, among them miRNA-96. The overexpression of microRNA-96 in human ex vivo erythropoiesis decreased γ-globin expression by 50%, whereas the knock-down of endogenous microRNA-96 increased γ-globin expression by 20%. Moreover, luciferase reporter assays showed that microRNA-96 negatively regulates expression of γ-globin in HEK293 cells, which depends on a seedless but highly complementary target site located within the coding sequence of γ-globin. Based on these results we conclude that microRNA-96 directly suppresses γ-globin expression and thus contributes to HbF regulation