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18
result(s) for
"Bon, Dimitra"
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Virological response after 6 week triple-drug regimens for hepatitis C: a proof-of-concept phase 2A cohort study
by
Sidharthan, Sreetha
,
Kapoor, Rama
,
McHutchison, John
in
Aged
,
Allergies
,
Antiviral Agents - therapeutic use
2015
Direct-acting antiviral drugs have a high cure rate and favourable tolerability for patients with hepatitis C virus (HCV). Shorter courses could improve affordability and adherence. Sofosbuvir and ledipasvir with ribavirin have high efficacy when taken for 8 weeks but not for 6 weeks. We assessed whether the addition of a third direct-acting antiviral drug to sofosbuvir and ledipasvir would allow a shorter treatment duration.
In this single-centre, open-label, phase 2A trial, we sequentially enrolled treatment-naive patients with HCV genotype 1 infection into three treatment groups: 12 weeks of sofosbuvir and ledipasvir; 6 weeks of sofosbuvir, ledipasvir, and GS-9669; or 6 weeks of sofosbuvir, ledipasvir, and GS-9451. Patients and investigators were not masked to treatment assignment. The primary endpoint was the propotion of patients with sustained viral response at 12 weeks after treatment completion (SVR12), assessed by serum HCV RNA concentrations lower than 43 IU/mL (the lower limit of quantification). We did an intention-to-treat analysis for the primary endpoint and adverse events. This study is registered with ClinicalTrials.gov, number NCT01805882.
Between Jan 11, 2013, and Dec 17, 2013, we enrolled 60 patients, and sequentially assigned them into three groups of 20. We noted an SVR12 in all 20 patients (100%, 95% CI 83–100) allocated to sofosbuvir and ledipasvir for 12 weeks; in 19 (95%, 75–100) of the 20 patients allocated to sofosbuvir, ledipasvir, and GS-9669 for 6 weeks (one patient relapsed 2 weeks after completion of treatment); and in 19 (95%, 75–100%) of the 20 patients allocated to sofosbuvir, ledipasvir, and GS-9451 for 6 weeks (one patient was lost to follow-up after reaching sustained viral response at 4 weeks). Most adverse events were mild and no patients discontinued treatment. Two serious adverse events occurred (pain after a post-treatment liver biopsy and vertigo), both unrelated to study drugs.
In this small proof-of-concept study, two different three-drug regimens that were given for 6 weeks resulted in high cure rates for HCV infection with excellent tolerability. Addition of a third potent direct-acting antiviral drug can reduce the duration of treatment required to achieve sustained viral response in patients with chronic HCV genotype 1 infection without cirrhosis.
National Institute of Allergy and Infectious Diseases (NIAID), National Cancer Institute and Clinical Center Intramural Program, German Research Foundation, National Institutes of Health, Gilead Sciences.
Journal Article
Comparison of strain elastography, point shear wave elastography using acoustic radiation force impulse imaging and 2D-shear wave elastography for the differentiation of thyroid nodules
by
Kyriakidou, Georgia
,
Herrmann, Eva
,
Friedrich-Rust, Mireen
in
Acoustics
,
Biology and Life Sciences
,
Cellular biology
2018
The aim of the study was to compare three different elastography methods, namely Strain Elastography (SE), Point Shear-Wave Elastography (pSWE) using Acoustic Radiation Force Impulse (ARFI)-Imaging and 2D-Shear Wave Elastography (2D-SWE), in the same study population for the differentiation of thyroid nodules.
All patients received a conventional ultrasound scan, SE and 2D-SWE, and all patients except for two received ARFI-Imaging. Cytology/histology of thyroid nodules was used as a reference method. SE measures the relative stiffness within the region of interest (ROI) using the surrounding tissue as reference tissue. ARFI mechanically excites the tissue at the ROI using acoustic pulses to generate localized tissue displacements. 2D-SWE measures tissue elasticity using the velocity of many shear waves as they propagate through the tissue.
84 nodules (73 benign and 11 malignant) in 62 patients were analyzed. Sensitivity, specificity and NPV of SE were 73%, 70% and 94%, respectively. Sensitivity, specificity and NPV of ARFI and 2D-SWE were 90%, 79%, 98% and 73%, 67%, 94% respectively, using a cut-off value of 1.98m/s for ARFI and 2.65m/s (21.07kPa) for 2D-SWE. The AUROC (Area under the Receiver Operating Characteristic) of SE, ARFI and 2D-SWE for the diagnosis of malignant thyroid nodules were 52%, 86% and 71%, respectively. A significant difference in AUROC was found between SE and ARFI (p = 0.008), while no significant difference was found between ARFI and SWE (86% vs. 71%, p = 0.31), or SWE and SE (71% vs. 52%, p = 0.26).
pSWE using ARFI and 2D-SWE showed comparable results for the differentiation of thyroid nodules. ARFI was superior to elastography using SE.
Journal Article
Downregulation of SPTAN1 is related to MLH1 deficiency and metastasis in colorectal cancer
2019
Colorectal cancers (CRCs) deficient in the DNA mismatch repair protein MutL homolog 1 (MLH1) display distinct clinicopathological features and require a different therapeutic approach compared to CRCs with MLH1 proficiency. However, the molecular basis of this fundamental difference remains elusive. Here, we report that MLH1-deficient CRCs exhibit reduced levels of the cytoskeletal scaffolding protein non-erythroid spectrin αII (SPTAN1), and that tumor progression and metastasis of CRCs correlate with SPTAN1 levels.
To investigate the link between MLH1 and SPTAN1 in cancer progression, a cohort of 189 patients with CRC was analyzed by immunohistochemistry. Compared with the surrounding normal mucosa, SPTAN1 expression was reduced in MLH1-deficient CRCs, whereas MLH1-proficient CRCs showed a significant upregulation of SPTAN1. Overall, we identified a strong correlation between MLH1 status and SPTAN1 expression. When comparing TNM classification and SPTAN1 levels, we found higher SPTAN1 levels in stage I CRCs, while stages II to IV showed a gradual reduction of SPTAN1 expression. In addition, SPTAN1 expression was lower in metastatic compared with non-metastatic CRCs. Knockdown of SPTAN1 in CRC cell lines demonstrated decreased cell viability, impaired cellular mobility and reduced cell-cell contact formation, indicating that SPTAN1 plays an important role in cell growth and cell attachment. The observed weakened cell-cell contact of SPTAN1 knockdown cells might indicate that tumor cells expressing low levels of SPTAN1 detach from their primary tumor and metastasize more easily.
Taken together, we demonstrate that MLH1 deficiency, low SPTAN1 expression, and tumor progression and metastasis are in close relation. We conclude that SPTAN1 is a candidate molecule explaining the tumor progression and metastasis of MLH1-deficient CRCs. The detailed analysis of SPTAN1 is now mandatory to substantiate its relevance and its potential value as a candidate protein for targeted therapy, and as a predictive marker of cancer aggressiveness.
Journal Article
Clinical Efficacy of Simulated Vitreoretinal Surgery to Prepare Surgeons for the Upcoming Intervention in the Operating Room
by
Schill, Markus
,
Müller, Michael
,
Wagner, Clemens
in
Analysis
,
Biology and Life Sciences
,
Bleeding
2016
To evaluate the efficacy of the virtual reality training simulator Eyesi to prepare surgeons for performing pars plana vitrectomies and its potential to predict the surgeons' performance.
In a preparation phase, four participating vitreoretinal surgeons performed repeated simulator training with predefined tasks. If a surgeon was assigned to perform a vitrectomy for the management of complex retinal detachment after a surgical break of at least 60 hours it was randomly decided whether a warmup training on the simulator was required (n = 9) or not (n = 12). Performance at the simulator was measured using the built-in scoring metrics. The surgical performance was determined by two blinded observers who analyzed the video-recorded interventions. One of them repeated the analysis to check for intra-observer consistency. The surgical performance of the interventions with and without simulator training was compared. In addition, for the surgeries with simulator training, the simulator performance was compared to the performance in the operating room.
Comparing each surgeon's performance with and without warmup trainingshowed a significant effect of warmup training onto the final outcome in the operating room. For the surgeries that were preceeded by the warmup procedure, the performance at the simulator was compared with the operating room performance. We found that there is a significant relation. The governing factor of low scores in the simulator were iatrogenic retinal holes, bleedings and lens damage. Surgeons who caused minor damage in the simulation also performed well in the operating room.
Despite the large variation of conditions, the effect of a warmup training as well as a relation between the performance at the simulator and in the operating room was found with statistical significance. Simulator training is able to serve as a warmup to increase the average performance.
Journal Article
Serum Sphingolipid Variations Associate with Hepatic Decompensation and Survival in Patients with Cirrhosis
2015
Sphingolipids constitute bioactive molecules with functional implications in liver homeostasis. Particularly, ablation of very long chain ceramides in a knockout mouse model has been shown to cause a severe hepatopathy.
We aimed to evaluate the serum sphingolipid profile of 244 patients with cirrhosis prospectively followed for a median period of 228±217 days via mass spectrometry.
We thereby observed a significant decrease of long and very long chain ceramides, particularly of C24ceramide, in patients with increasing severity of cirrhosis (p<0.001). Additionally, hydropic decompensation, defined by clinical presentation of ascites formation, was significantly correlated to low C24ceramide levels (p<0.001) while a significant association to hepatic decompensation and poor overall survival was observed for low serum concentrations of C24ceramide (p<0.001) as well. Multivariate analysis further identified low serum C24ceramide to be independently associated to overall survival (standard beta = -0.001, p = 0.022).
In our current analysis serum levels of very long chain ceramides show a significant reciprocal correlation to disease severity and hepatic decompensation and are independently associated with overall survival in patients with cirrhosis. Serum sphingolipid metabolites and particularly C24ceramide may constitute novel molecular targets of disease severity, hepatic decompensation and overall prognosis in cirrhosis and should be further evaluated in basic research studies.
Journal Article
Transcatheter or surgical aortic valve implantation in chronic dialysis patients: a German Aortic Valve Registry analysis
2021
ObjectivesThe aim of this study was to compare outcomes of transcatheter and surgical aortic valve implantation in chronic dialysis patients with aortic valve stenosis (AS).BackgroundChronic dialysis patients undergoing heart valve surgery are at higher risk for morbidity and mortality. Whether interventional techniques can reduce this risk is unclear because dialysis patients have thus far been excluded from randomized trials.MethodsChronic dialysis patients with AS enrolled in the German Aortic Valve Registry (GARY) between 2012 and 2015 were analyzed to compare transcatheter aortic valve implantation (TAVI n = 661) with surgical aortic valve replacement (SAVR n = 457). Propensity scores for inverse probability of treatment weighting (IPTW) were used to adjust the comparison of the two treatment groups for potential confounders.ResultsTAVI patients were older (78 ± 7.3 vs. 69 ± 10.2 years, p < 0.01, unadjusted) and had more comorbidities. Mortality at 1 year was the same (TAVI: 33.4% vs. SAVR 35.0%, p = 0.72, IPTW-adjusted) while it was lower with TAVI at 30 days (8.6% vs. 15.0%, p = 0.02, IPTW-adjusted). TAVI patients required more pacemaker implantation and showed more aortic regurgitation. SAVR patients required more blood transfusions and had longer hospital stay. Diabetes mellitus, atrial fibrillation, previous PCI, urgent procedure and EuroSCORE were associated with elevated 30-day mortality. Atrial fibrillation and older age were independent risk factor of 1-year mortality in both groups.ConclusionsChronic dialysis patients with AS undergoing TAVI or SAVR had the same 1-year mortality, although survival at 30 days was better with TAVI. These results suggest that TAVI may improve peri-procedural outcomes.
Journal Article
Investigation of NS3 Protease Resistance-Associated Variants and Phenotypes for the Prediction of Treatment Response to HCV Triple Therapy
2016
Triple therapy of chronic hepatitis C virus (HCV) infection with boceprevir (BOC) or telaprevir (TVR) leads to virologic failure in many patients which is often associated with the selection of resistance-associated variants (RAVs). These resistance profiles are of importance for the selection of potential rescue treatment options. In this study, we sequenced baseline NS3 RAVs population-based and investigated the sensitivity of NS3 phenotypes in an HCV replicon assay together with clinical factors for a prediction of treatment response in a cohort of 165 German and Swiss patients treated with a BOC or TVR-based triple therapy. Overall, the prevalence of baseline RAVs was low, although the frequency of RAVs was higher in patients with virologic failure compared to those who achieved a sustained virologic response (SVR) (7% versus 1%, P = 0.06). The occurrence of RAVs was associated with a resistant NS3 quasispecies phenotype (P<0.001), but the sensitivity of phenotypes was not associated with treatment outcome (P = 0.2). The majority of single viral and host predictors of SVR was only weakly associated with treatment response. In multivariate analyses, low AST levels, female sex and an IFNL4 CC genotype were independently associated with SVR. However, a combined analysis of negative predictors revealed a significantly lower overall number of negative predictors in patients with SVR in comparison to individuals with virologic failure (P<0.0001) and the presence of 2 or less negative predictors was indicative for SVR. These results demonstrate that most single baseline viral and host parameters have a weak influence on the response to triple therapy, whereas the overall number of negative predictors has a high predictive value for SVR.
Journal Article
Endogenous intrahepatic IFNs and association with IFN-free HCV treatment outcome
by
Osinusi, Anu
,
Virtaneva, Kimmo
,
Herrmann, Eva
in
Antigens
,
Antiviral agents
,
Antiviral Agents - administration & dosage
2014
BACKGROUND. Hepatitis C virus (HCV) infects approximately 170 million people worldwide and may lead to cirrhosis and hepatocellular carcinoma in chronically infected individuals. Treatment is rapidly evolving from IFN-α-based therapies to IFN-α-free regimens that consist of directly acting antiviral agents (DAAs), which demonstrate improved efficacy and tolerability in clinical trials. Virologic relapse after DAA therapy is a common cause of treatment failure; however, it is not clear why relapse occurs or whether certain individuals are more prone to recurrent viremia. METHODS. We conducted a clinical trial using the DAA sofosbuvir plus ribavirin (SOF/RBV) and performed detailed mRNA expression analysis in liver and peripheral blood from patients who achieved either a sustained virologic response (SVR) or relapsed. RESULTS. On-treatment viral clearance was accompanied by rapid downregulation of IFN-stimulated genes (ISGs) in liver and blood, regardless of treatment outcome. Analysis of paired pretreatment and end of treatment (EOT) liver biopsies from SVR patients showed that viral clearance was accompanied by decreased expression of type II and III IFNs, but unexpectedly increased expression of the type I IFN IFNA2. mRNA expression of ISGs was higher in EOT liver biopsies of patients who achieved SVR than in patients who later relapsed. CONCLUSION. These results suggest that restoration of type I intrahepatic IFN signaling by EOT may facilitate HCV eradication and prevention of relapse upon withdrawal of SOF/RBV. TRIAL REGISTRATION. ClinicalTrials.gov NCT01441180.
Journal Article
IFNL4-ΔG Genotype Is Associated With Slower Viral Clearance in Hepatitis C, Genotype-1 Patients Treated With Sofosbuvir and Ribavirin
by
Tang, Wei
,
Herrmann, Eva
,
O'Brien, Thomas R.
in
Alleles
,
Antiviral Agents - administration & dosage
,
Antiviral Agents - therapeutic use
2014
Response to pegylated interferon-alpha and ribavirin (IFNα/RBV) treatment for chronic hepatitis C virus (HCV) infection is influenced by host genetic factors, but their role for IFN-α-free, direct-acting antiviral (DAA) regimens is unclear. An exonic deletion allele (IFNL4-ΔG) bolsters the established association with IFN-α/RBV therapy treatment outcome of another IFNL4 variant, rs 12979860, which is located upstream of IFNL3 (IL28B). We report that in patients treated with the DAA sofosbuvir along with RBV, IFNL4-ΔG is associated with slower early viral decay, due to slower loss of free virus (P = .039) and decreased drug efficacy (P = .048), suggesting functional relevance of IFN-λ4 in IFN-α-free DAA therapies.
Journal Article
Propensity matched comparison of TAVI and SAVR in intermediate-risk patients with severe aortic stenosis and moderate-to-severe chronic kidney disease: a subgroup analysis from the German Aortic Valve Registry
2022
ObjectiveWe compared TAVI vs. SAVR in patients with moderate-to-severe chronic kidney disease (eGFR 15–60 ml/min/1.73 m2) for whom both procedures could possibly be considered (age ≤ 80 years, STS-score 4–8).BackgroundAccording to both ACC/AHA and ESC/EACTS recent guidelines, aortic stenosis may be treated with either transcatheter (TAVI) or surgical (SAVR) aortic valve replacement in a subgroup of patients. A shared therapeutic decision is made by a heart team based on individual factors, including chronic kidney disease (CKD).MethodsData from the large nationwide German Aortic Valve Registry were used. A propensity score method was used to select 704 TAVI and 374 SAVR matched patients. Primary endpoint was 1-year survival. Secondary endpoints were clinical complications, including pacemaker implantation, vascular complications, myocardial infarction, bleeding, and the need for new-onset dialysis.ResultsOne-year survival was similar (HR [95% CI] for TAVI 1.271 [0.795, 2.031], p = 0.316), with no divergence in Kaplan–Meier curves. In spite of post-procedural short-term survival being numerically higher for TAVI patients and 1-year survival being numerically higher for SAVR patients, such differences did not reach statistical significance (96.4% vs. 94.2%, p = 0.199, and 86.2% vs. 81.2%, p = 0.316, respectively). In weighted analyses, pacemaker implantation, vascular complications, and were significantly more common with TAVI; whereas myocardial infarction, bleeding requiring transfusion, and longer ICU-stay and overall hospitalization were higher with SAVR. Temporary dialysis was more common with SAVR (p < 0.0001); however, a probable need for chronic dialysis was rare and similar in both groups.ConclusionBoth TAVI and SAVR led to comparable and excellent results in patients with moderate-to-severe CKD in an intermediate-risk population of patients with symptomatic severe aortic stenosis for whom both therapies could possibly be considered.
Journal Article