81 research outputs found
Incidence of HIV-related anal cancer remains increased despite long-term combined antiretroviral treatment: results from the french hospital database on HIV.
PURPOSE: To study recent trends in the incidence of anal cancer in HIV-infected patients receiving long-term combined antiretroviral treatment (cART) compared with the general population. PATIENTS AND METHODS: From the French Hospital Database on HIV, we identified 263 cases of invasive anal squamous cell carcinoma confirmed histologically between 1992 and 2008. We compared incidence rates of anal cancer across four calendar periods: 1992-1996 (pre-cART period), 1997-2000 (early cART period), and 2001-2004 and 2005-2008 (recent cART periods). Standardized incidence ratios (SIRs) were calculated by using general population incidence data from the French Network of Cancer Registries. RESULTS: In HIV-infected patients, the hazard ratio (HR) in the cART periods versus the pre-cART period was 2.5 (95% CI, 1.28 to 4.98). No difference was observed across the cART calendar periods (HR, 0.9; 95% CI, 0.6 to 1.3). In 2005-2008, HIV-infected patients compared with the general population had an excess risk of anal cancer, with SIRs of 109.8 (95% CI, 84.6 to 140.3), 49.2 (95% CI, 33.2 to 70.3), and 13.1 (95% CI, 6.8 to 22.8) for men who have sex with men (MSM), other men, and women, respectively. Among patients with CD4 cell counts above 500/μL for at least 2 years, SIRs were 67.5 (95% CI, 41.2 to 104.3) when the CD4 nadir was less than 200/μL for more than 2 years and 24.5 (95% CI, 17.1 to 34.1) when the CD4 nadir was more than 200/μL. CONCLUSION: Relative to that in the general population, the risk of anal cancer in HIV-infected patients is still extremely high, even in patients with high current CD4 cell counts. cART appears to have no preventive effect on anal cancer, particularly in MSM
Stability of nonlinear Vlasov-Poisson equilibria through spectral deformation and Fourier-Hermite expansion
We study the stability of spatially periodic, nonlinear Vlasov-Poisson
equilibria as an eigenproblem in a Fourier-Hermite basis (in the space and
velocity variables, respectively) of finite dimension, . When the advection
term in Vlasov equation is dominant, the convergence with of the
eigenvalues is rather slow, limiting the applicability of the method. We use
the method of spectral deformation introduced in [J. D. Crawford and P. D.
Hislop, Ann. Phys. 189, 265 (1989)] to selectively damp the continuum of
neutral modes associated with the advection term, thus accelerating
convergence. We validate and benchmark the performance of our method by
reproducing the kinetic dispersion relation results for linear (spatially
homogeneous) equilibria. Finally, we study the stability of a periodic
Bernstein-Greene-Kruskal mode with multiple phase space vortices, compare our
results with numerical simulations of the Vlasov-Poisson system and show that
the initial unstable equilibrium may evolve to different asymptotic states
depending on the way it was perturbed.Comment: 15 pages, 11 figure
Management of inflammatory bowel disease in France: a nationwide survey among private gastroenterologists
Introduction : Les données sur la gestion actuelle des patients atteints de maladie inflammatoire chronique intestinale (MICI) sont rares. Matériel et méthodes : Il s’agissait d’une enquête nationale sur internet réalisée auprès de gastro-entérologues libéraux sous forme de questions à choix multiples en Juin 2012. Résultats : 375 patients atteints de MICI ont été inclus : 48 % d’entre eux avaient une rectocolite hémorragique (RCH). Un antécédent d’hospitalisation concernait un tiers des patients atteints de MICI, et un antécédent de chirurgie 40 % des patients atteints de maladies de Crohn (MC). Deux tiers des patients avaient une maladie active le jour de la consultation (l’activité de la maladie était jugée par le médecin sans score). Soixante pour cent des patients atteints de RCH étaient traités par 5-aminosalicylés contre 18,5 % de MC (p<0,001). Parmi les patients traités par anti-TNF, seulement 4,5 % recevaient un traitement concomitant par immunomodulateur. La moitié des patients avaient eu une coloscopie dans l’année. Concernant le dépistage du cancer colorectal, des biopsies étagées et la chromoendoscopie étaient réalisées dans respectivement 75 % et 40 % des cas. Un score endoscopique d’activité n’était utilisé que chez 10 % des patients. Environ un tiers des patients ayant une MICI avait eu une imagerie dans l’année : l’entéro-IRM représentait environ la moitié de ces prescriptions. Le scanner a été prescrit chez 12 % des patients et l’échographie chez seulement 7 %. Conclusion : De nombreux patients ont encore une maladie active à l’ère des biothérapies, et la proportion de patients recevant une association anti-TNF et azathioprine reste faible en médecine libérale. La coloscopie est toujours la référence pour évaluer l’activité des MICI même si l’IRM est de plus en plus pratiquée. La chromoendoscopie et les scores endoscopiques sont encore sous-utilisés.Background: Data on the current management of inflammatory bowel disease (IBD) are scarce. Materials and Methods: This was a web-based nationwide survey consisting of multiple-choice questions among private gastroenterologists in France in June 2012. Results: 375 IBD patients were analyzed: 48% had ulcerative colitis (UC). History of hospitalization concerned one third of IBD patients, and history of surgery 40% of Crohn’s disease patients (CD). Two thirds of IBD patients had active disease (disease activity was judged by the physician without using a validated tool or a score). The proportion of patients treated with anti-TNF therapy was significantly lower in UC (18.9%) than in CD (38.9 %; p<0.0001). Sixty per cent of UC patients were treated with 5-aminosalicylates as compared with 18.5% of in CD (p<0.0001). Among anti-TNF treated patients, only 4.5% were receiving concomitant immunomodulator. Half of IBD patients had a colonoscopy within the past year. Regarding colorectal cancer screening, random biopsies and chromoendoscopy were performed in 75% and 40% of cases, respectively. An endoscopic score was used for only 10% of IBD patients. About one third of IBD patients had imaging studies within the past year, MRI enterography representing about half of them. Abdominal CT was prescribed for 12% of IBD patients and abdominal ultrasound for only 7% of them. Conclusions: Many patients still have active disease in the biologics era despite an increasing use of immunosuppressive therapy, and the number of patients receiving combination therapy is low in private practice. Colonoscopy remains the gold standard to assess IBD even though MRI is increasingly used in these patients. Chromoendoscopy and endoscopy scores are not often used
Matter-wave diffraction in time with a linear potential
Diffraction in time of matter waves incident on a shutter which is removed at
time is studied in the presence of a linear potential. The solution is
also discussed in phase space in terms of the Wigner function. An alternative
configuration relevant to current experiments where particles are released from
a hard wall trap is also analyzed for single-particle states and for a
Tonks-Girardeau gas.Comment: 11 pages, 6 figure
Implementing two-photon interference in the frequency domain with electro-optic phase modulators
Frequency-entangled photons can be readily produced using parametric
down-conversion. We have recently shown how such entanglement could be
manipulated and measured using electro-optic phase modulators and narrow-band
frequency filters, thereby leading to two-photon interference patterns in the
frequency domain. Here we introduce new theoretical and experimental
developments showing that this method is potentially a competitive platform for
the realization of quantum communication protocols in standard
telecommunication fibres. We derive a simple theoretical expression for the
coincidence probabilities and use it to optimize a Bell inequality.
Furthermore, we establish an equivalence between the entangled- photon scheme
and a classical interference scheme. Our measurements of two-photon
interference in the frequency domain yield raw visibilities in excess of 99%.
We use our high quality setup to experimentally validate the theoretical
predictions, and in particular we report a violation of the CH74 inequality by
more than 18 standard deviations.Comment: 19 pages, 3 figure
Matter wave pulses characteristics
We study the properties of quantum single-particle wave pulses created by
sharp-edged or apodized shutters with single or periodic openings. In
particular, we examine the visibility of diffraction fringes depending on
evolution time and temperature; the purity of the state depending on the
opening-time window; the accuracy of a simplified description which uses
``source'' boundary conditions instead of solving an initial value problem; and
the effects of apodization on the energy width.Comment: 11 pages, 11 figure
Prognostic role of HPV integration status and molecular profile in advanced anal carcinoma: An ancillary study to the epitopes-HPV02 trial.
peer reviewedSquamous Cell Carcinoma of the Anal canal (SCCA) is a rare disease associated with a Human Papillomavirus (HPV) infection in most cases, predominantly the HPV16 genotype. About 15% of SCCA are diagnosed in metastatic stage and some will relapse after initial chemoradiotherapy (CRT). Treatment of patients by Docetaxel, Cisplatin and 5-fluorouracil (DCF) has been recently shown to improve their complete remission and progression-free survival. The aim of this retrospective study was to explore the impact of HPV infection, HPV DNA integration, TERT promoter mutational status and somatic mutations of oncogenes on both progression-free (PFS) and overall survivals (OS) of patients treated by DCF. Samples obtained from 49 patients included in the Epitopes-HPV02 clinical trial, diagnosed with metastatic or non-resectable local recurrent SCCA treated by DCF, were used for analyses. Median PFS and OS were not associated with HPV status. Patients with episomal HPV had an improved PFS compared with SCCA patients with integrated HPV genome (p=0.07). TERT promoter mutations were rarely observed and did not specifically distribute in a subset of SCCA and did not impact DCF efficacy. Among the 42 genes investigated, few gene alterations were observed, and were in majority amplifications (68.4%), but none were significantly correlated to PFS. As no biomarker is significantly associated with patients' survival, it prompts us to include every patient failing CRT or with metastatic disease in DCF strategy
Practical recipes for the model order reduction, dynamical simulation, and compressive sampling of large-scale open quantum systems
This article presents numerical recipes for simulating high-temperature and
non-equilibrium quantum spin systems that are continuously measured and
controlled. The notion of a spin system is broadly conceived, in order to
encompass macroscopic test masses as the limiting case of large-j spins. The
simulation technique has three stages: first the deliberate introduction of
noise into the simulation, then the conversion of that noise into an equivalent
continuous measurement and control process, and finally, projection of the
trajectory onto a state-space manifold having reduced dimensionality and
possessing a Kahler potential of multi-linear form. The resulting simulation
formalism is used to construct a positive P-representation for the thermal
density matrix. Single-spin detection by magnetic resonance force microscopy
(MRFM) is simulated, and the data statistics are shown to be those of a random
telegraph signal with additive white noise. Larger-scale spin-dust models are
simulated, having no spatial symmetry and no spatial ordering; the
high-fidelity projection of numerically computed quantum trajectories onto
low-dimensionality Kahler state-space manifolds is demonstrated. The
reconstruction of quantum trajectories from sparse random projections is
demonstrated, the onset of Donoho-Stodden breakdown at the Candes-Tao sparsity
limit is observed, a deterministic construction for sampling matrices is given,
and methods for quantum state optimization by Dantzig selection are given.Comment: 104 pages, 13 figures, 2 table
Dysplasie anale chez les patients porteurs d'une condylomatose diffuse : mosaïque ou homogénéité ?
REIMS-BU Santé (514542104) / SudocSudocFranceF
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