Cambios ambientales del último milenio en sedimentos lacustres del Lago Thompson, Patagonia Chilena Norte

Este estudio se enfoca en un análisis multiproxy de un testigo sedimentario del Lago Thompson (area 1 km2; 751 masl ; 45°38’S 72°47’W) obtenido en 2008 (LT08-E, 130 cm), con el objetivo de documentar la variabilidad climática durante el último milenio en la Patagonia Chilena Norte y su impacto sobre el ambiente. El modelo de datación se basó en cinco fechados de 14C. Los resultados de 210Pb y 137 Cs no permitieron estimar la tasa de sedimentación para la parte superficial del núcleo. El lago Thompson esta caracterizado por una pequeña cuenca de suaves pendientes y sus sedimentos están dominados por limo arcilloso y partículas amorfas (principalmente diatomeas). Esto último es sustentado por la relación atómica de carbono/nitrógeno (C/N) que indica el origen fitoplanctónico del sedimento (8-10). Los perfiles de rayos –X, susceptibilidad magnética y LOI 550ºC evidencian dos depósitos volcánicos en 1410-1440 y 1780-1790 AD. Los perfiles de C/N y sílice biogénica (SiB) sugieren una alta productividad durante un periodo equivalente a la Pequeña Edad del Hielo (1650-1850 AD), con una máxima intensidad durante ~1800 AD. Desde 1850 AD hasta la actualidad, los perfiles de LOI 550ºC y SiB evidencian una reciente eutrofización y aumento del nivel del lago (asociado con aumento de temperaturas y humedad). Además, los perfiles de SiB presentan una correlación inversa con las temperaturas reconstruidas por anillos de árboles en la Patagonia. El contenido de diatomeas es dominado por especies planctónicas (Aulacoseira sp. y Cyclotella sp.), mientras que taxa bentónicos no muestran una buena diversificación en comparación a otros lagos de la Patagonia. La abundancia de diatomeas muestra respuestas específicas a los depósitos volcánicos con una disminución de Aulacoseira sp.. La relación planctónica/bentónica permite identificar dos periodos de alto y bajo nivel del lago coincidiendo con fases húmedas y secas de la Pequeña Edad de Hielo (1200-1650 y 1650-1850 AD). La realización de análisis sedimentológicos, geoquímicos y de microfósiles permitiría una mejor caracterización de los modelos de depositación del sedimento (impregnación del núcleo sedimentario) y de la interacción entre depósitos volcánicos y diatomeas. Agradecimientos a Fondecyt Nº1070508, FNRS 1360 2007-2010 y ULg CFRA 1060 2009-2010

Human prostate supports more efficient replication of HIV-1 R5 than X4 strains ex vivo

<p>Abstract</p> <p>Background</p> <p>In order to determine whether human prostate can be productively infected by HIV-1 strains with different tropism, and thus represent a potential source of HIV in semen, an organotypic culture of prostate from men undergoing prostatic adenomectomy for benign prostate hypertrophy (BPH) was developed. The presence of potential HIV target cells in prostate tissues was investigated using immunohistochemistry. The infection of prostate explants following exposures with HIV-1 R5, R5X4 and X4 strains was analyzed through the measure of RT activity in culture supernatants, the quantification of HIV DNA in the explants and the detection of HIV RNA+ cells <it>in situ</it>.</p> <p>Results</p> <p>The overall prostate characteristics were retained for 2^1/2weeks in culture. Numerous potential HIV-1 target cells were detected in the prostate stroma. Whilst HIV-1 R5_SF162strain consistently productively infected prostatic T lymphocytes and macrophages, the prototypic X4_IIIBstrain and a primary R5X4 strain showed less efficient replication in this organ.</p> <p>Conclusion</p> <p>The BPH prostate is a site of HIV-1 R5 replication that could contribute virus to semen. A limited spreading of HIV-1 X4 and R5X4 in this organ could participate to the preferential sexual transmission of HIV-1 R5 strains.</p

Anti-glomerular basement membrane disease, ulcerative colitis, and primary sclerosing cholangitis: link or co-incidence?

International audienceUlcerative colitis, primary sclerosing cholangitis, and anti-glomerular basement membrane disease (anti-GBM) are three rare immune diseases with incompletely under-stood pathogenic mechanisms. We describe here the case of a 29-year-old man with ulcer-ative colitis and primary sclerosing cholang -itis who, eight years later, developed anti-GBM disease with destruction of all glomeruli leading to end-stage kidney disease. Association of these three immune diseases in the same patient has never been described. Because HLA-mediated susceptibility cannot be incriminated completely in our case, we hypothesize that environmental factors or previous immunosuppressive treatment used might be the link

073: Very long-term effects of pacing therapy in Hypertrophic Obstructive Cardiomyopathy (HOCM)

The clinical value of DDD pacing as primary treatment of HOCM remains controversial. Very long-term data are lacking.Aimssingle-centre observational study aimed at describing the very long term effects on symptoms, clinical and echocardiographic outcomesPatients54 patients (59±14 years) with symptomatic (NYHA Class >2) drug-refractory HOCM implanted with a DDD pacemaker with or without defibrillator between 1991 and 2007 and followed up to 20 years (mean 11.5; range 0,4-21,8).Main resultsare summarised in table. No patient had myomectomy or septal ablation during follow-up (f/u). NYHA functional class and other symptoms were significantly improved at 1-2 years and at the end of f/u. Left ventricular outflow tract (LVOT) gradient decreased by a mean of 78% at 1-2 years and 89% at end f/u consistent with SAM resolution. LV ejection fraction decreased over time with a mean value of 56% at end f/u without evidence of cavity dilatation. The actuarial survival rate was 90% at 5-yrs and 65% at 10-yrs. 24 patients died, 19 from non cardiac cause and 5 cardiovascular. 2 patients had heart transplant after 8 and 13yrs.ConclusionThe clinical and echocardiographic outcome of HOCM patients treated by DDD pacing seems favourable, inviting to re-evaluate the exact value of the therapy in further controlled studiesTable – Main results.Baseline3 months1-2 yearsEnd f/uP valueNYHA functional class, (%)<0,0001Grade 10313536Grade 243535957Grade 3521667Grade 45000Syncope/nearsyncope (%)76/482/22/22/2<0,0001Angina (%)57444<0,0001LVOT gradient (mmHg)79±3620±2411±158±21<0,0001SAM (%)96383016<0,0001LVEF (%)63,5±7,561±759±756±90,05LVEDD (%)47±5NANA43±120,3

A POSSIBLE ROLE OF GUT MICROBIOTA IN THE BEHAVORIAL CONTROL OF ALCOHOL-DEPENDENT SUBJECTS

These observations suggest that alterations at the level of the gut microbiota influence the gut permeability and activate specific inflammation pathways that are related to psychological symptoms of alcoholdependence. Altogether these observations are consistent with a role of inflammation as one mediator of a gut-brain communication in AD patients

Système rénine-angiotensine et cancers urologiques / Renin-angiotensin system and urological cancers.

International audienceIntroduction: A controversy animates the literature on the potential role of the rennin-angiotensin system (RAS) in tumorogenesis. The objective of this review was to determine the involvement of this pathway in cancer, and more specifically in urological cancers. Material and Method: We made a systematic review of articles referenced in Pubmed, using the following keywords alone or combined: cancer, renin, angiotensin, VEGF, AT1R, antagonists of angiotensin-2 receptors, inhibitors of angiotensinogen converting. Results: Many types of cancers overexpress AT1-R in their tumoral tissues (breast, stomach, bladder, astrocytoma, glioblastoma, ovary, uterus, pancreas, kidney, prostate, adrenal gland). Ang-II can induce VEGF-A expression and promote neoangiogenesis, but also can trigger different molecular pathways involved in cell proliferation or inhibit apoptosis. Several xenograft murin models demonstrated anti-tumoral efficacy of RAS blockers, alone or using combined therapies, targeting angiogenesis and slowing down tumor growth. Retrospective studies in patients have also revealed a better progression-free survival and a better response to therapies in those treated with RAS blockers. Conclusion: Many data seem to demonstrate the involvement of the RAS in carcinogenesis, as well as anti-tumoral effect of RAS blockers in addition to anti-cancer treatments. Clinical data are now expected to confirm these experimental findings

Cytogénétique des carcinomes rénaux [Cytogenetics profiles of renal carcinoma]

National audienc

Low CAIX expression and absence of VHL gene mutation are associated with tumor aggressiveness and poor survival of clear cell renal cell carcinoma.

International audienceWe attempted to describe, in a series of clear cell renal cell carcinoma (RCC), the relationship between CAIX expression, VHL gene mutations, tumor characteristics and outcome. Radical nephrectomy was performed in 100 patients. Genomic DNA was extracted from frozen tumor samples. Four amplimers covering the whole coding sequence of the VHL gene were synthesized by PCR and sequenced. The monoclonal antibody M75 was used to evaluate CAIX protein expression immunohistochemically. VHL mutations were identified in 58 patients (58%) and high CAIX expression (>85%) was observed in 78 (78%). Tumors with VHL mutation showed higher CAIX expression than those without (p = 0.02). Low CAIX expression and absence of VHL mutation were associated with a more advanced tumors e.g., higher T stages and presence of metastases. VHL mutation and high CAIX expression predicted longer progression-free survival (p = 0.037) and disease-specific survival (p = 0.001), respectively. In combination, they defined three prognostic groups (p = 0.002): (i) good prognosis, defined as VHL mutation and high CAIX (2-year survival: 86%), (ii) intermediate prognosis with either VHL mutation or high CAIX (69%), and (iii) poor prognosis with no VHL mutation and low CAIX (45%, median survival 18 months). CAIX expression, but not VHL mutational status, was an independent prognostic factor in multivariate analysis. Taken together, CAIX expression and VHL mutational status are able to stratify patients with clear cell RCC into distinct groups with regards to clinicopathological variables and prognosis, with low CAIX expression and absence of VHL mutation being associated with a poor clinicopathological phenotype and diminished survival

A Phase III Randomized Study Comparing a Chemotherapy with Cisplatin and Etoposide to a Etoposide Regimen without Cisplatin for Patients with Extensive Small-Cell Lung Cancer

IntroductionIn a literature meta-analysis, we showed survival benefits for regimens including cisplatin [hazard ratio (HR) 0.61; 95% confidence interval (CI), 0.57–0.66] and for those including etoposide (HR 0.65; 0.61–0.69). That benefit was mainly observed when etoposide alone or in combination with cisplatin was included in the chemotherapy regimens. Our objective was to determine if chemotherapy with both drugs improves survival in comparison to a non-platinum regimen with etoposide.MethodsExtensive small-cell lung cancer patients were randomized between cisplatin–etoposide (CE) and ifosfamide + etoposide + epirubicin regimen (IVE) between 2000 and 2013.Results176 and 170 eligible patients were allocated to CE and IVE (315 deaths were required before analysis), respectively. Objective response rates were not significantly different: 60% with CE and 59% with IVE. No statistically significant difference in median survival and 1-year and 2-year was observed with rates of 9.6 months, 31 and 5% for CE and 10 months, 39 and 9% for IVE, respectively. HR was 0.84 (95% CI 0.68–1.05, p = 0.16). Only two prognostic factors for survival were retained in multivariate analysis: sex with HR = 0.69 (95% CI 0.49–0.97, p = 0.03) and performance status with HR = 0.53 (95% CI 0.49–0.97, p &lt; 0.0001). After adjustment for these prognostic factors, HR for survival was 0.83 (95% CI 0.65–1.08, p = 0.17). There was more thrombopenia in the CE regimen and more leukopenia with IVE.ConclusionCombination of CE failed to improve survival in comparison to an etoposide-containing regimen without cisplatin.Clinical Trial Registrationhttps://clinicaltrials.gov/ct2/show/NCT00658580?term=ELCWP+01994&amp;rank=1, identifier NCT00658580

Enquêter dans les partis politiques:Perspectives comparées

Ce dossier se situe à la croisée de deux mouvements récents qui traversent la science politique française. Le premier tient au constat que l’étude des partis politiques s’est largement transformée ces dernières années. D’abord, cet objet « canonique » a fait l’objet d’une attention renouvelée, et en particulier un nombre important de thèses, récemment soutenues ou en cours, y sont consacrées. Ensuite, ces travaux, émanant donc pour une large part de jeunes chercheur(se)s, ont pour point commun de s’appuyer sur des enquêtes, entendues au sens large comme des méthodes de production de données originales, que celles-ci soient qualitatives (par observations et entretiens) ou quantitatives (passation de questionnaires auprès d’adhérents d’un parti politique, par exemple). Cette multiplication de travaux empiriques sur les partis permet une confrontation des expériences d’enquête, afin de réfléchir collectivement à ces pratiques de recherche, pour elles-mêmes mais aussi pour ce qu’elles nous apprennent de l’objet de recherche parti politique (...)