Anharmonic vs. relaxational sound damping in glasses: I. Brillouin scattering from densified silica

This series discusses the origin of sound damping and dispersion in glasses. In particular, we address the relative importance of anharmonicity versus thermally activated relaxation. In this first article, Brillouin-scattering measurements of permanently densified silica glass are presented. It is found that in this case the results are compatible with a model in which damping and dispersion are only produced by the anharmonic coupling of the sound waves with thermally excited modes. The thermal relaxation time and the unrelaxed velocity are estimated.Comment: 9 pages with 7 figures, added reference

Femoro-tibial knee osteoarthritis: One or two X-rays? Results from a population-based study

International audienceOBJECTIVE:Our objective was to compare the use of both anteroposterior (AP) extended-knee X-ray and semi-flexed X-ray (current gold standard) versus the use of semi-flexed X-ray alone to detect femoro-tibial osteoarthritis (OA).METHODS:Individuals 40 to 75 years of age with symptomatic hip and/or knee OA (Kellgren/Lawrence [KL] score≥2) were recruited using a multiregional prevalence survey in France. Both AP and schuss X-rays were performed and read; two years later, the same examiner, blinded to the results of the first reading, performed a second reading of the schuss X-ray. We compared the KL stages of each knee and analyzed osteophyte detection and localization, joint space narrowing (JSN), and the relationship to obesity.RESULTS:The analysis included 350 participants with OA of various stages. Comparing the two readings showed that a higher proportion of patients had KL≥2 when the two X-ray views were combined (right knee: P<0.0001; left knee: P<0.001). There were no differences when using the schuss X-ray alone versus in combination with an AP X-ray in terms of detecting JSN, osteophytes. A comparison of schuss X-ray alone versus AP X-ray alone demonstrated the superiority of the schuss view for evaluating JSN (P=0.0001 and P=0.0001) and no difference in osteophyte detection.CONCLUSION:Our study shows that the schuss view alone was sufficient for detecting knee osteophytes and JSN. Using one X-ray rather than two will reduce medical costs and irradiation burden. Using two views seems preferable for epidemiological studies

Association between hip morphology and prevalence, clinical severity and progression of hip osteoarthritis over 3 years: The knee and hip osteoarthritis long-term assessment cohort results

International audienceOBJECTIVE:To assess the effects of variations in hip morphology on prevalence, clinical severity and progression of hip osteoarthritis.METHODS:From 2007 to 2009, we conducted a study of 242 patients aged between 40 and 75 years with symptomatic lower limb osteoarthritis, as part of a population-based osteoarthritis cohort study in France. Standard radiographs of both hips were obtained at baseline and at three years. The progression of hip osteoarthritis was evaluated according to the radiological Kellgren-Lawrence score (KL) and clinical severity from the scores on a Visual Analogic Scale (VAS) for pain recorded yearly. Five measures were used to describe hip morphology: centre edge angle, acetabular index (AI), vertical centre anterior angle, acetabular depth and neck-shaft angle.RESULTS:Of the 484 hips studied, 205 (42%) showed osteoarthritis at baseline and 16 (11 right and 5 left) underwent joint replacement during the follow-up. AI was the morphological measure most consistently and strongly associated with radiographic osteoarthritis at baseline (odds-ratio=1.05, 95% CI: 1.01-1.08 per degree of angle change), clinical severity (correlation coefficient with VAS during 3 years=0.15, P=0.004), radiological progression (odds-ratio=1.05, 95% CI: 1.00-1.10 per degree) and joint replacement (hazard ratio=1.18, 95% CI: 1.07-1.29 per degree).CONCLUSIONS:Acetabular obliquity and especially AI is strongly, and likely causally, associated with the existence, severity and progression of hip osteoarthritis

Relationship between hip dysplasia, pain, and osteoarthritis in a cohort of patients with hip symptoms

International audienceOBJECTIVE: The relationship between acetabular dysplasia (HD) and hip osteoarthritis (OA) remains unclear, especially for mild forms of dysplasia. Our objectives were to estimate the prevalence of HD in a population-based sample with symptoms and to evaluate potential associations linking HD, hip OA, and hip pain. METHODS: Individuals 40 to 75 years of age with symptoms in 1 or both hips were recruited during a multiregional prevalence survey. All study participants underwent examination and radiographs. Radiographs were evaluated using Kellgren-Lawrence staging (with stages ≥ 2 indicating hip OA) and HD measures [center-edge (CE) angle, acetabular inclination angle (HTE), acetabular depth (AD), and vertical center-anterior margin angle]. RESULTS: We studied both hips of 842 individuals (1684 hips), among whom 203 had hip OA. Compared to left hips, right hips had significantly smaller CE angles and significantly greater AD and HTE values (p ≤ 0.001). Overall, the prevalence of HD ranged from 7.6% to 22.2% of the hips depending on the measure used. The prevalence of HD was higher in individuals with hip OA, with significant differences for abnormal HTE (19.1% vs 11.4%; p < 0.0001) and abnormal CE (11.3% vs 7.5%; p = 0.04). By logistic regression, only abnormal HTE remained associated with OA. Same-side hip pain was not statistically more common in individuals with HD after stratification on OA status (p = 0.12). CONCLUSION: Our study confirms the relationship between OA and HD, particularly as defined based on the HTE angle

The KHOALA cohort of knee and hip osteoarthritis in France

International audienceOBJECTIVES: This study aimed to describe the prevalence of symptomatic knee and hip osteoarthritis (OA) and its course over time, as well as identify prognostic factors of OA course and determinants of costs and access to care in France in a patient cohort. METHODS: Subjects aged 40 to 75 years, with uni- or bilateral symptomatic hip and/or knee OA (ACR criteria), Kellgren and Lawrence (KL) stage 2 or greater, were recruited from a French national prevalence survey for the multicenter KHOALA cohort study. Data collected at baseline included sociodemographic and clinical data; WOMAC, IKS and Harris scores for pain and function; MAQ score for physical activity; functional comorbidity index; GHQ28 score for psychological status; and SF-36 (generic) and OAKHQOL (specific) scores for quality of life. Blood and urine samples were collected. RESULTS: Eight hundred and seventy-eight subjects were included, 222 with OA of the hip (mean age 61.2±8.8 years), 607 knee (mean age 62.0±8.5 years) and 49 both hip and knee (mean age 64.9±7.9 years). Mean body mass index was 26.9±4.5 for hip OA and 30.3±6.3 for knee OA. Hip and knee OA patients had 1.99 and 2.06 comorbidities, on average, respectively. Disease severity on X-rays for KL stages 2, 3 and 4 for hip OA was 69.8, 26.1 and 4.1%, respectively, and for knee OA, 44.5, 30.3, and 25.2%. As compared with population norms, age- and sex-standardized SF-36 scores were greatly decreased for both knee and hip OA in all dimensions, particularly physical and emotional dimensions. PERSPECTIVES: Patients will be followed up annually, alternately by mail and clinical visit. This cohort of representative patients with knee and hip OA will be an opportunity for future collaborative research

Cytoreductive Surgery With or Without Hyperthermic Intraperitoneal Chemotherapy for Gastric Cancer With Peritoneal Metastases (CYTO-CHIP study): A Propensity Score Analysis

International audiencePURPOSE:Gastric cancer (GC) with peritoneal metastases (PMs) is a poor prognostic evolution. Cytoreductive surgery (CRS) yields promising results, but the impact of hyperthermic intraperitoneal chemotherapy (HIPEC) remains controversial. Here we aimed to compare outcomes between CRS-HIPEC versus CRS alone (CRSa) among patients with PMs from GC.PATIENTS AND METHODS:From prospective databases, we identified 277 patients with PMs from GC who were treated with complete CRS with curative intent (no residual nodules > 2.5 mm) at 19 French centers from 1989 to 2014. Of these patients, 180 underwent CRS-HIPEC and 97 CRSa. Tumor burden was assessed using the peritoneal cancer index. A Cox proportional hazards regression model with inverse probability of treatment weighting (IPTW) based on propensity score was used to assess the effect of HIPEC and account for confounding factors.RESULTS:After IPTW adjustment, the groups were similar, except that median peritoneal cancer index remained higher in the CRS-HIPEC group (6 v 2; P = .003). CRS-HIPEC improved overall survival (OS) in both crude and IPTW models. Upon IPTW analysis, in CRS-HIPEC and CRSa groups, median OS was 18.8 versus 12.1 months, 3- and 5-year OS rates were 26.21% and 19.87% versus 10.82% and 6.43% (adjusted hazard ratio, 0.60; 95% CI, 0.42 to 0.86; P = .005), and 3- and 5-year recurrence-free survival rates were 20.40% and 17.05% versus 5.87% and 3.76% (P = .001), respectively; the groups did not differ regarding 90-day mortality (7.4% v 10.1%, respectively; P = .820) or major complication rate (53.7% v 55.3%, respectively; P = .496).CONCLUSION:Compared with CRSa, CRS-HIPEC improved OS and recurrence-free survival, without additional morbidity or mortality. When complete CRS is possible, CRS-HIPEC may be considered a valuable therapy for strictly selected patients with limited PMs from GC

High Risk of Anal and Rectal Cancer in Patients With Anal and/or Perianal Crohn’s Disease

International audienceBackground & AimsLittle is known about the magnitude of the risk of anal and rectal cancer in patients with anal and/or perineal Crohn’s disease. We aimed to assess the risk of anal and rectal cancer in patients with Crohn’s perianal disease followed up in the Cancers Et Surrisque Associé aux Maladies Inflammatoires Intestinales En France (CESAME) cohort.MethodsWe collected data from 19,486 patients with inflammatory bowel disease (IBD) enrolled in the observational CESAME study in France, from May 2004 through June 2005; 14.9% of participants had past or current anal and/or perianal Crohn’s disease. Subjects were followed up for a median time of 35 months (interquartile range, 29–40 mo). To identify risk factors for anal cancer in the total CESAME population, we performed a case-control study in which participants were matched for age and sex.ResultsAmong the total IBD population, 8 patients developed anal cancer and 14 patients developed rectal cancer. In the subgroup of 2911 patients with past or current anal and/or perianal Crohn’s lesions at cohort entry, 2 developed anal squamous-cell carcinoma, 3 developed perianal fistula–related adenocarcinoma, and 6 developed rectal cancer. The corresponding incidence rates were 0.26 per 1000 patient-years for anal squamous-cell carcinoma, 0.38 per 1000 patient-years for perianal fistula–related adenocarcinoma, and 0.77 per 1000 patient-years for rectal cancer. Among the 16,575 patients with ulcerative colitis or Crohn’s disease without anal or perianal lesions, the incidence rate of anal cancer was 0.08 per 1000 patient-years and of rectal cancer was 0.21 per 1000 patient-years. Among factors tested by univariate conditional regression (IBD subtype, disease duration, exposure to immune-suppressive therapy, presence of past or current anal and/or perianal lesions), the presence of past or current anal and/or perianal lesions at cohort entry was the only factor significantly associated with development of anal cancer (odds ratio, 11.2; 95% CI, 1.18-551.51; P = .03).ConclusionsIn an analysis of data from the CESAME cohort in France, patients with anal and/or perianal Crohn’s disease have a high risk of anal cancer, including perianal fistula–related cancer, and a high risk of rectal cancer