MAARS: a novel high-content acquisition software for the analysis of mitotic defects in fission yeast

Faithful segregation of chromosomes during cell division relies on multiple processes such as chromosome attachment and correct spindle positioning. Yet mitotic progression is defined by multiple parameters, which need to be quantitatively evaluated. To study the spatiotemporal control of mitotic progression, we developed a high-content analysis (HCA) approach that combines automated fluorescence microscopy with real-time quantitative image analysis and allows the unbiased acquisition of multiparametric data at the single-cell level for hundreds of cells simultaneously. The Mitotic Analysis and Recording System (MAARS) provides automatic and quantitative single-cell analysis of mitotic progression on an open-source platform. It can be used to analyze specific characteristics such as cell shape, cell size, metaphase/anaphase delays, and mitotic abnormalities including spindle mispositioning, spindle elongation defects, and chromosome segregation defects. Using this HCA approach, we were able to visualize rare and unexpected events of error correction during anaphase in wild-type or mutant cells. Our study illustrates that such an expert system of mitotic progression is able to highlight the complexity of the mechanisms required to prevent chromosome loss during cell division

Combination of blood tests for significant fibrosis and cirrhosis improves the assessment of liver-prognosis in chronic hepatitis C

BACKGROUND: Recent longitudinal studies have emphasised the prognostic value of noninvasive tests of liver fibrosis and cross-sectional studies have shown their combination significantly improves diagnostic accuracy. AIM: To compare the prognostic accuracy of six blood fibrosis tests and liver biopsy, and evaluate if test combination improves the liver-prognosis assessment in chronic hepatitis C (CHC). METHODS: A total of 373 patients with compensated CHC, liver biopsy (Metavir F) and blood tests targeting fibrosis (APRI, FIB4, Fibrotest, Hepascore, FibroMeter) or cirrhosis (CirrhoMeter) were included. Significant liver-related events (SLRE) and liver-related deaths were recorded during follow-up (started the day of biopsy). RESULTS: During the median follow-up of 9.5 years (3508 person-years), 47 patients had a SLRE and 23 patients died from liver-related causes. For the prediction of first SLRE, most blood tests allowed higher prognostication than Metavir F [Harrell C-index: 0.811 (95% CI: 0.751-0.868)] with a significant increase for FIB4: 0.879 [0.832-0.919] (P = 0.002), FibroMeter: 0.870 [0.812-0.922] (P = 0.005) and APRI: 0.861 [0.813-0.902] (P = 0.039). Multivariate analysis identified FibroMeter, CirrhoMeter and sustained viral response as independent predictors of first SLRE. CirrhoMeter was the only independent predictor of liver-related death. The combination of FibroMeter and CirrhoMeter classifications into a new FM/CM classification improved the liver-prognosis assessment compared to Metavir F staging or single tests by identifying five subgroups of patients with significantly different prognoses. CONCLUSIONS: Some blood fibrosis tests are more accurate than liver biopsy for determining liver prognosis in CHC. A new combination of two complementary blood tests, one targeted for fibrosis and the other for cirrhosis, optimises assessment of liver-prognosis

Acoustic radiation force impulse: a new ultrasonographic technology for the widespread noninvasive diagnosis of liver fibrosis:

Background/aims: As a module of a standard ultrasound imaging device, acoustic radiation force impulse (ARFI) is a new technology for liver stiffness evaluation (LSE). We aimed to evaluate accuracy, feasibility, reproducibility, and training effect of ARFI for liver fibrosis evaluation.Methods: One hundred and one patients with chronic liver disease had LSE by Fibroscan and ARFI. LSE by ARFI was performed in the two liver lobes by two operators: an expert and a novice. Correlation and agreement were evaluated by the Pearson (Rp) and intraclass (Ric) correlation coefficients. The independent reference for liver fibrosis was fibrosis blood tests. Results: ARFI results, ranging from 0.7 to 4.6 m/s, were well correlated with Fibroscan results (Rp=0.76). Fibroscan had a significantly higher area under the receiver operating characteristic curve (AUROC) than ARFI for the perprotocol diagnosis of significant fibrosis: 0.890±0.034 versus 0.795±0.047 (P=0.04). However, LSE failure occurred in zero patients using ARFI versus six patients using Fibroscan (P=0.03). Thus, on an intention-to-diagnose basis, Fibroscan and ARFI AUROCs for the diagnosis of significant fibrosis were not different: 0.791±0.049 versus 0.793±0.046 (P=0.98). Interobserver agreement was very good (Ric=0.84) and excellent for ARFI interquartile range (IQR)≤0.30 (Ric=0.91). Indeed, agreement was independently predicted only by ARFI IQR, but not by LSE result as earlier observed for Fibroscan. ARFI AUROC was 0.876±0.057 in patients with ARFI IQR ratio≤0.30, and Fibroscan AUROC was 0.912±0.034 in patients with Fibroscan IQR ratio less than 0.21 (P=0.59). Intersite ARFI agreement between the two liver lobes was fair (Ric=0.60). There was no training effect for LSE by ARFI. Conclusion: ARFI is highly feasible and reproducible, and provides diagnostic accuracy similar to Fibroscan. This new device seems noteworthy for the widespread noninvasive diagnosis of liver fibrosis

Radiofrequency ablation of hepatocellular carcinoma: Mono or multipolar?

BACKGROUND AND AIMS: Thermo-ablation by radiofrequency is recognized as a curative treatment for early-stage hepatocellular carcinoma. However, local recurrence may occur because of incomplete peripheral tumor destruction. Multipolar radiofrequency has been developed to increase the size of the maximal ablation zone. We aimed to compare the efficacy of monopolar and multipolar radiofrequency for the treatment of hepatocellular carcinoma and determine factors predicting failure. METHODS: A total of 171 consecutive patients with 214 hepatocellular carcinomas were retrospectively included. One hundred fifty-eight tumors were treated with an expandable monopolar electrode and 56 with a multipolar technique using several linear bipolar electrodes. Imaging studies at 6 weeks after treatment, then every 3 months, assessed local effectiveness. Radiofrequency failure was defined as persistent residual tumor after two sessions (primary radiofrequency failure) or local tumor recurrence during follow-up. This study received institutional review board approval (number 2014/77). RESULTS: Imaging showed complete tumor ablation in 207 of 214 lesions after the first session of radiofrequency. After a second session, only two cases of residual viable tumor were observed. During follow-up, there were 46 local tumor recurrences. Thus, radiofrequency failure occurred in 48/214 (22.4%) cases. By multivariate analysis, technique (P < 0.001) and tumor size (P = 0.023) were independent predictors of radiofrequency failure. Failure rate was lower with the multipolar technique for tumors < 25 mm (P = 0.023) and for tumors between 25 and 45 mm (P = 0.082). There was no difference for tumors ≥ 45 mm (P = 0.552). CONCLUSIONS: Compared to monopolar radiofrequency, multipolar radiofrequency improves tumor ablation with a subsequent lower rate of local tumor recurrence

Liver fibrosis diagnosis by blood test and elastography in chronic hepatitis C: agreement or combination?

BACKGROUND: In chronic hepatitis C, the European Association for the Study of the Liver and the Asociacion Latinoamericana para el Estudio del Higado recommend performing transient elastography plus a blood test to diagnose significant fibrosis; test concordance confirms the diagnosis. AIM: To validate this rule and improve it by combining a blood test, FibroMeter (virus second generation, Echosens, Paris, France) and transient elastography (constitutive tests) into a single combined test, as suggested by the American Association for the Study of Liver Diseases and the Infectious Diseases Society of America. METHODS: A total of 1199 patients were included in an exploratory set (HCV, n = 679) or in two validation sets (HCV ± HIV, HBV, n = 520). Accuracy was mainly evaluated by correct diagnosis rate for severe fibrosis (pathological Metavir F ≥ 3, primary outcome) by classical test scores or a fibrosis classification, reflecting Metavir staging, as a function of test concordance. RESULTS: Score accuracy: there were no significant differences between the blood test (75.7%), elastography (79.1%) and the combined test (79.4%) (P = 0.066); the score accuracy of each test was significantly (P < 0.001) decreased in discordant vs. concordant tests. Classification accuracy: combined test accuracy (91.7%) was significantly (P < 0.001) increased vs. the blood test (84.1%) and elastography (88.2%); accuracy of each constitutive test was significantly (P < 0.001) decreased in discordant vs. concordant tests but not with combined test: 89.0 vs. 92.7% (P = 0.118). Multivariate analysis for accuracy showed an interaction between concordance and fibrosis level: in the 1% of patients with full classification discordance and severe fibrosis, non-invasive tests were unreliable. The advantage of combined test classification was confirmed in the validation sets. CONCLUSIONS: The concordance recommendation is validated. A combined test, expressed in classification instead of score, improves this rule and validates the recommendation of a combined test, avoiding 99% of biopsies, and offering precise staging

Evolution of noninvasive tests of liver fibrosis is associated with prognosis in patients with chronic hepatitis C

UNLABELLED: No data are available about the prediction of long-term survival using repeated noninvasive tests of liver fibrosis in chronic hepatitis C (CHC). We aimed to assess the prognostic value of 3-year liver stiffness measurement (LSM), aspartate aminotransferase to platelet ratio index (APRI), and fibrosis 4 (FIB-4) evolution in CHC. CHC patients with two LSM (1,000-1,500 days interval) were prospectively included. Blood fibrosis tests APRI and FIB-4 were calculated the day of baseline (bLSM) and follow-up (fLSM) LSM. Evolution of fibrosis tests was expressed as delta: (follow-up-baseline results)/duration. Date and cause of death were recorded during follow-up that started the day of fLSM. In all, 1,025 patients were included. Median follow-up after fLSM was 38.0 months (interquartile range [IQR]: 27.7-46.1) during which 35 patients died (14 liver-related death) and seven had liver transplantation. Prognostic accuracy (Harrell C-index) of multivariate models including baseline and delta results was not significantly different between LSM and FIB-4 (P ≥ 0.24), whereas FIB-4 provided more accurate prognostic models than APRI (P = 0.03). By multivariate analysis including LSM variables, overall survival was independently predicted by bLSM, delta (dLSM), and sustained virological response (SVR). Prognosis was excellent in patients having bLSM <7 kPa, SVR, or no increase (<1 kPa/year) in 7-14 kPa bLSM. Prognosis was significantly impaired in patients with an increase (≥ 1 kPa/year) in 7-14 kPa bLSM, or decrease (≤ 0 kPa/year) in ≥ 14 kPa bLSM (P = 0.949 between these two groups). Patients with an increase (>0 kPa/year) in ≥ 14 kPa bLSM had the worst prognosis. Baseline and delta FIB-4 also identified patient subgroups with significantly different prognosis. CONCLUSION: Three-year evolution of noninvasive tests of liver fibrosis has a strong prognostic value in CHC patients. These tests should be repeated to monitor patients and predict their outcome

Exploring the role of the Sun’s motion in terrestrial comet impacts

The cratering record on the Earth and Moon shows that our planet has been exposed to high velocity impacts for much or all of its existence. Some of these craters were produced by the impact of long-period comets (LPCs). These probably originated in the Oort Cloud, and were put into their present orbits through gravitational perturbations arising from the Galactic tide and stellar encounters, both of which are modulated by the solar motion about the Galaxy. Here we construct dynamical models of these mechanisms in order to predict the time-varying impact rate of LPCs and the angular distribution of their perihelia (which is observed to be non-uniform). Comparing the predictions of these dynamical models with other models, we conclude that cometary impacts induced by the solar motion contribute only a small fraction of terrestrial impact craters over the past 250 Myr. Over this time-scale, the apparent cratering rate is dominated by a secular increase towards the present, which might be the result of the disruption of a large asteroid. Our dynamical models, together with the solar apex motion, predict a non-uniform angular distribution of the perihelia, without needing to invoke the existence of a massive body in the outer Oort Cloud. Our results are reasonably robust to changes in the parameters of the Galaxy model, Oort Cloud, and stellar encounters.Peer reviewedFinal Accepted Versio

Antiviral effect of ribavirin in early non-responders to interferon monotherapy assessed by kinetics of hepatitis C virus RNA and hepatitis C virus core antigen

BACKGROUND/AIMS: To evaluate the efficacy of ribavirin, given in second intention in non-responders to interferon alone, by studying viral kinetics. METHODS: We conducted a trial including 203 patients with chronic hepatitis C, naïve of treatment. Patients were treated with interferon three times a week with or without ribavirin and amantadine according to response. Viral kinetics were assessed by serial measurements of HCV RNA (bDNA 3.0 and Monitor 2.0) and a new assay, trak-C, able to quantify total Hepatitis C virus (HCV) core antigen. RESULTS: A significant initial drop in HCV RNA or HCV core antigen, under interferon alone, was associated with response to therapy, -4.85+/-1.33 log for HCV RNA in sustained responders versus -1.86+/-1.53 log for others groups, P<0.001. In patients receiving ribavirin in second intention, we also observed a similar drop in HCV RNA and HCV core antigen, predictive of sustained response, -2.67+/-1.26 log for HCV RNA in sustained responders versus -0.44+/-0.49 log in non-responders, P<0.001. CONCLUSIONS: Ribavirin has probably an additional antiviral effect in interferon treated patients. Kinetics of HCV RNA and HCV core antigen under treatment are highly predictive of a sustained virological response

Doppler ultrasonography devices, including elastography, allow for accurate diagnosis of severe liver fibrosis

OBJECTIVES: Advanced chronic liver disease is frequent yet largely underdiagnosed. Doppler-US is a common examination and we recently identified three simple Doppler-US signs associated with severe liver fibrosis. Recent Doppler-US devices include elastography modules, allowing for liver stiffness measurement (LSM). Our aim was to assess whether the use of elastography following positive simple Doppler-US signs improves the detection of severe liver fibrosis in a single Doppler-US examination. METHODS: 514 patients with chronic liver disease who consecutively underwent percutaneous liver biopsy were included in the study. All patients had a Doppler-US examination and LSM with Virtual Touch Quantification (VTQ) on the same day as a liver biopsy. A subset of 326 patients also had LSM with 2D shear wave elastography (SSI). Severe fibrosis was defined as Metavir F ≥ 3 on liver biopsy. RESULTS: Multivariate analysis confirmed our three simple Doppler-US signs (liver surface irregularity, splenomegaly ≥110 mm, and demodulation of hepatic veins) as independently associated with severe fibrosis. The presence of at least one of these three signs showed 85.6% sensitivity and 36.1% specificity for the diagnosis of severe liver fibrosis. Using VTQ (≥1.59 m/s) where there was a positive Doppler-US sign increased the specificity to 80.8%, at the cost of a decrease in sensitivity (73.7%). Similar results were obtained with SSI (≥9.5 kPa), with 73.3% specificity and 81.5% sensitivity. CONCLUSION: Elastography improves the accuracy of Doppler-US in the detection of severe fibrosis. This two-step procedure will help radiologists to accurately identify patients who need to be referred to specialist hepatologists during routine Doppler-US examinations

Liver stiffness in nonalcoholic fatty liver disease: A comparison of supersonic shear imaging, FibroScan, and ARFI with liver biopsy

Nonalcoholic fatty liver disease (NAFLD) has become a major public health issue. The goal of this study was to assess the clinical use of liver stiffness measurement (LSM) evaluated by supersonic shear imaging (SSI), FibroScan, and acoustic radiation force impulse (ARFI) in a cohort of NAFLD patients who underwent liver biopsy. A total of 291 NAFLD patients were prospectively enrolled from November 2011 to February 2015 at 2 French university hospitals. LSM was assessed by SSI, FibroScan (M probe), and ARFI within two weeks prior to liver biopsy. Calculations of the area under the receiver operating curve (AUROC) were performed and compared for the staging of liver fibrosis. AUROC for SSI, FibroScan, and ARFI were 0.86, 0.82, and 0.77 for diagnoses of ≥F2; 0.89, 0.86, and 0.84 for ≥F3; and 0.88, 0.87, and 0.84 for F4, respectively. SSI had a higher accuracy than ARFI for diagnoses of significant fibrosis (≥F2) (P = 0.004). Clinical factors related to obesity such as body mass index ≥ 30 kg/m(2) , waist circumference ≥102 cm or increased parietal wall thickness were associated with LSM failures when using SSI or FibroScan and with unreliable results when using ARFI. In univariate analysis, FibroScan values were slightly correlated with NAFLD activity score and steatosis (R = 0.28 and 0.22, respectively), whereas SSI and ARFI were not; however, these components of NAFLD did not affect LSM results in multivariate analysis. The cutoff values for SSI and FibroScan for staging fibrosis with a sensitivity ≥90% were very close: 6.3/6.2 kPa for ≥F2, 8.3/8.2 kPa for ≥F3, and 10.5/9.5 kPa for F4. CONCLUSION: Although obesity is associated with an increase in LSM failure, the studied techniques and especially SSI provide high value for the diagnosis of liver fibrosis in NAFLD patients. (Hepatology 2016;63:1817-1827)