440 research outputs found

    Fermiology and superconductivity studies on the non-tetrachalcogenafulvalene structured organic superconductor beta-(BDA-TTP)_2SbF_6

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    The quantum oscillatory effect and superconductivity in a non-tetrachalcogenafulvalene (TCF) structure based organic superconductor beta-(BDA-TTP)_2SbF_6 are studied. Here the Shubnikov-de Haas effect (SdH) and angular dependent magnetoresistance oscillations (AMRO) are observed. The oscillation frequency associated with a cylindrical Fermi surface is found to be about 4050 tesla, which is also verified by the tunnel diode oscillator (TDO) measurement. The upper critical field Hc2 measurement in a tilted magnetic field and the TDO measurement in the mixed state reveal a highly anisotropic superconducting nature in this material. We compared physical properties of beta-(BDA-TTP)_2SbF_6 with typical TCF structure based quasi two-dimensional organic conductors. A notable feature of beta-(BDA-TTP)_2SbF_6 superconductor is a large value of effective cyclotron mass m_c^*=12.4+/1.1 m_e, which is the largest yet found in an organic superconductor. A possible origin of the enhanced effective mass and its relation to the superconductivity are briefly discussed.Comment: 8 pages, 10 figure

    The relationship between transmission time and clustering methods in Mycobacterium tuberculosis epidemiology

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    YesBackground: Tracking recent transmission is a vital part of controlling widespread pathogens such as Mycobacterium tuberculosis. Multiple methods with specific performance characteristics exist for detecting recent transmission chains, usually by clustering strains based on genotype similarities. With such a large variety of methods available, informed selection of an appropriate approach for determining transmissions within a given setting/time period is difficult. Methods: This study combines whole genome sequence (WGS) data derived from 324 isolates collected 2005–2010 in Kinshasa, Democratic Republic of Congo (DRC), a high endemic setting, with phylodynamics to unveil the timing of transmission events posited by a variety of standard genotyping methods. Clustering data based on Spoligotyping, 24-loci MIRU-VNTR typing, WGS based SNP (Single Nucleotide Polymorphism) and core genome multi locus sequence typing (cgMLST) typing were evaluated. Findings: Our results suggest that clusters based on Spoligotyping could encompass transmission events that occurred almost 200 years prior to sampling while 24-loci-MIRU-VNTR often represented three decades of transmission. Instead, WGS based genotyping applying low SNP or cgMLST allele thresholds allows for determination of recent transmission events, e.g. in timespans of up to 10 years for a 5 SNP/allele cut-off. Interpretation: With the rapid uptake of WGS methods in surveillance and outbreak tracking, the findings obtained in this study can guide the selection of appropriate clustering methods for uncovering relevant transmission chains within a given time-period. For high resolution cluster analyses, WGS-SNP and cgMLST based analyses have similar clustering/timing characteristics even for data obtained from a high incidence setting.ERC grant [INTERRUPTB; no. 311725] to BdJ, FG and CJM; an ERC grant to TS [PhyPD; no. 335529]; an FWO PhD fellowship to PM [grant number 1141217N]; the Leibniz Science Campus EvolLUNG for MM and SN; the German Centre for Infection Research (DZIF) for TAK, MM, CU, PB and SN; a SNF SystemsX grant (TBX) to JP and TS and a Marie Heim-Vögtlin fellowship granted to DK by the Swiss National Science Foundation. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation - Flanders (FWO) and the Flemish Government – department EWI

    Percutaneous treatment with Mitraclip for functional mitral regurgitation: medium-term follow up according to left ventricular function

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    Background: Functional mitral regurgitation (FMR) is a bad prognosis condition despite optimal medical treatment. Nowadays there is an open debate about the surgical versus percutaneous treatment. The main objective of this study is to evaluate the mid-term follow up clinical outcomes of patients with FMR treated with MitraClip((R)) system, according to their left ventricular ejection fraction (LVEF). Methods: Data was obtained from two experienced centers in transcatheter mitral valve repair (TMVR). All consecutive cases of severe FMR undergoing TMVR in both centers with the same inclusion criteria were included prospectively in this study and followed-up. Periodical follow-ups with clinical and echocardiographic evaluation were scheduled from the baseline procedure, at 3 months and then yearly. Results: From October 2015 to October 2019, a total of 119 patients with FMR at 2 centers in Spain underwent TMVR with the MitraClip((R)) procedure and were included in this study. The mean age was 73.8+/-8.9 years old and 32 patients (26.9%) were female. A 39.5% of cases [47] had a LVEF 30% (group 2). There was a similar distribution in cardiovascular risk factors, age and other diseases. All MitraClip((R)) implantations were elective and procedural success was achieved in 110 patients (92.4%) with a similar distribution between the groups. There were no differences in procedural time and the number of implanted clips. The median follow-up was 22.6 months (IQR, 11.43-34.98 months). The primary combined endpoint occurred in the 41.6% of the global cohort, 57.5% in group 1 and 30.99% in group 2 (P=0.036). LVEF was associated to the main event in the multivariate analysis (HR 2.09, 95% CI: 1.12-3.89; P=0.02). Conclusions: The MitraClip edge-to-edge technique is a safe and effective procedure for the treatment of FMR. In this study, patients with LVEF >30% treated with Mitraclip presented better clinical cardiovascular outcomes than those with a LVEF </=30%. Regardless clinical outcomes, at the end of the follow-up, there was a sustained reduction in MR grades and an important improvement in NYHA functional class

    Prognosis After Resection of Barcelona Clinic Liver Cancer (BCLC) Stage 0, A, and B Hepatocellular Carcinoma: A Comprehensive Assessment of the Current BCLC Classification

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    Background: Although the Barcelona Clinic Liver Cancer (BCLC) staging system has been largely adopted in clinical practice, recent studies have questioned the prognostic stratification of this classification schema, as well as the proposed treatment allocation of patients with a single large tumor. Methods: Patients who underwent curative-intent hepatectomy for histologically proven hepatocellular carcinoma (HCC) between 1998 and 2017 were identified using an international multi-institutional database. Overall survival (OS) among patients with BCLC stage 0, A, and B was examined. Patients with a single large tumor were classified as BCLC stage A1 and were independently assessed. Results: Among 814 patients, 68 (8.4%) were BCLC-0, 310 (38.1%) were BCLC-A, 279 (34.3%) were BCLC-A1, and 157 (19.3%) were BCLC-B. Five-year OS among patients with BCLC stage 0, A, A1, and B HCC was 86.2%, 69.0%, 56.9%, and 49.9%, respectively (p < 0.001). Among patients with very early- and early-stage HCC (BCLC 0, A, and A1), patients with BCLC stage A1 had the worst OS (p = 0.0016). No difference in survival was noted among patients undergoing surgery for BCLC stage A1 and B HCC (5-year OS: 56.9% vs. 49.9%; p = 0.259) even after adjusting for competing factors (hazard ratio 0.83, 95% confidence interval 0.54-1.28; p = 0.40). Conclusion: Prognosis following liver resection among patients with BCLC-A1 HCC was similar to patients presenting with BCLC-B tumors. Surgery provided acceptable long-term outcomes among select patients with BCLC-B HCC. Designation into BCLC stage B should not be considered an a priori contraindication to surgery.info:eu-repo/semantics/publishedVersio

    Effect of Surgical Margin Width on Patterns of Recurrence among Patients Undergoing R0 Hepatectomy for T1 Hepatocellular Carcinoma: an International Multi-Institutional Analysis

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    Introduction: Although a positive surgical margin is a known prognostic factor for recurrence, the optimal surgical margin width in the context of an R0 resection for early-stage hepatocellular carcinoma (HCC) is still debated. The aim of the current study was to examine the impact of wide (> 1 cm) versus narrow (< 1 cm) surgical margin status on the incidence and recurrence patterns among patients with T1 HCC undergoing an R0 hepatectomy. Methods: Between 1998 and 2017, patients with T1 HCC who underwent R0 hepatectomy for stage T1 HCC were identified using an international multi-institutional database. Recurrence-free survival (RFS) was estimated, and recurrence patterns were examined based on whether patients had a wide versus narrow resection margins. Results: Among 404 patients, median patient age was 66 years (IQR: 58-73). Most patients (n = 326, 80.7%) had surgical margin 1 cm margin. The majority of patients had early recurrences ( 1 cm: 85.7%, p = 0.141); recurrence site was mostly intrahepatic ( 1 cm: 61.9%, p = 0.169). The 1-, 3-, and 5-year RFS among patients with margin 1 cm, respectively (p = 0.02). Among patients undergoing anatomic resection, resection margin did not impact RFS (3-year RFS: 1 cm: 58.9%, p = 0.169), whereas in the non-anatomic resection group, margin width > 1 cm was associated with a better 3-year RFS compared to margin 1 cm remained protective against recurrence (HR = 0.50, 95%CI 0.28-0.89), whereas Child-Pugh B (HR = 2.13, 95%CI 1.09-4.15), AFP > 20 ng/mL (HR = 1.71, 95%CI 1.18-2.48), and presence of microscopic lymphovascular invasion (HR = 1.48, 95%CI 1.01-2.18) were associated with a higher hazard of recurrence. Conclusion: Resection margins > 1 cm predicted better RFS among patients undergoing R0 hepatectomy for T1 HCC, especially small (< 5 cm) HCC. Although resection margin width did not influence outcomes after anatomic resection, wider margins were more important among patients undergoing non-anatomic liver resections.info:eu-repo/semantics/publishedVersio

    Serum α-Fetoprotein Levels at Time of Recurrence Predict Post-Recurrence Outcomes Following Resection of Hepatocellular Carcinoma

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    Introduction: Although preoperative α-fetoprotein (AFP) has been recognized as an important tumor marker among patients with hepatocellular carcinoma (HCC), the predictive value of AFP levels at the time of recurrence (rAFP) on post-recurrence outcomes has not been well examined. Methods: Patients undergoing curative-intent resection of HCC between 2000 and 2017 were identified using a multi-institutional database. The impact of rAFP on post-recurrence survival, as well as the impact of rAFP relative to the timing and treatment of HCC recurrence were examined. Results: Among 852 patients who underwent resection of HCC, 307 (36.0%) individuals developed a recurrence. The median rAFP level was 8 ng/mL (interquartile range 3-100). Among the 307 patients who developed recurrence, 3-year post-recurrence survival was 48.5%. Patients with rAFP > 10 ng/mL had worse 3-year post-recurrence survival compared with individuals with rAFP 10 vs. 10 vs. 10 ng/mL had a twofold higher hazard of death in the post-recurrence setting (hazard ratio 1.96, 95% confidence interval 1.26-3.04). Conclusion: AFP levels at the time of recurrence following resection of HCC predicted post-recurrence survival independent of the secondary treatment modality used. Evaluating AFP levels at the time of recurrence can help inform post-recurrence risk stratification of patients with recurrent HCC.info:eu-repo/semantics/publishedVersio

    The multikinase inhibitor EC‐70124 synergistically increased the antitumor activity of doxorubicin in sarcomas

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    Cytotoxic drugs like doxorubicin remain as the most utilized agents in sarcoma treatment. However, advanced sarcomas are often resistant, thus stressing the need for new therapies aimed to overcome this resistance. Multikinase inhibitors provide an efficient way to target several pro-tumorigenic pathways using a single agent and may constitute a valuable strategy in the treatment of sarcomas, which frequently show an aberrant activation of pro-tumoral kinases. Therefore, we studied the antitumor activity of EC-70124, an indolocarbazole analog that have demonstrated a robust ability to inhibit a wide range of pro-survival kinases. Evaluation of the phospho-kinase profile in cell-of-origin sarcoma models and/or sarcoma primary cell lines evidenced that PI3K/AKT/mTOR, JAK/STAT or SRC were among the most highly activated pathways. In striking contrast with the structurally related drug midostaurin, EC-70124 efficiently prevented the phosphorylation of these targets and robustly inhibited proliferation through a mechanism associated to the induction of DNA damage, cell cycle arrest and apoptosis. In addition, EC-70124 was able to partially reduce tumor growth in vivo. Importantly, this compound inhibited the expression and activity of ABC efflux pumps involved in drug resistance. In line with this ability, we found that the combined treatment of EC-70124 with doxorubicin resulted in a synergistic cytotoxic effect in vitro and an increased antitumor activity of this cytotoxic drug in vivo. Altogether, these results uncover the capability of the novel multikinase inhibitor EC-70124 to counteract drug resistance in sarcoma and highlight its therapeutic potential when combined with current treatmentsPeer ReviewedPostprint (author's final draft

    The role of TET-mediated DNA hydroxymethylation in prostate cancer

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    Massie C. is funded by an ERC grant (337905) and acknowledges support of the University of Cambridge, the Cancer Research UK Cambridge Centre and Hutchison Whampoa Limited. Claessens F. and Joniau S. hold grants from Fonds Wetenschappelijk Onderzoek-Vlaanderen (GOA9816N, G.0684.12N, G.0830.13N). Van den Broeck T. is supported by a PhD fellowship from Fonds Wetenschappelijk Onderzoek-Vlaanderen (11ZO616N). This work was also supported by the KU Leuven (GOA/15/017) and Kom op tegen Kanker.Ten-eleven translocation (TET) proteins are recently characterized dioxygenases that regulate demethylation by oxidizing 5-methylcytosine to 5-hydroxymethylcytosine and further derivatives. The recent finding that 5hmC is also a stable and independent epigenetic modification indicates that these proteins play an important role in diverse physiological and pathological processes such as neural and tumor development. Both the genomic distribution of (hydroxy)methylation and the expression and activity of TET proteins are dysregulated in a wide range of cancers including prostate cancer. Up to now it is still unknown how changes in TET and 5(h)mC profiles are related to the pathogenesis of prostate cancer. In this review, we explore recent advances in the current understanding of how TET expression and function are regulated in development and cancer. Furthermore, we look at the impact on 5hmC in prostate cancer and the potential underlying mechanisms. Finally, we tried to summarize the latest techniques for detecting and quantifying global and locus-specific 5hmC levels of genomic DNA.PostprintPeer reviewe

    Which behavioural and exercise interventions targeting fatigue show the most promise in multiple sclerosis? A systematic review with narrative synthesis and meta-analysis

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    Fatigue is a common and highly debilitating symptom of multiple sclerosis (MS). This meta-analytic systematic review with detailed narrative synthesis examined randomised-controlled (RCTs) and controlled trials of behavioural and exercise interventions targeting fatigue in adults with MS to assess which treatments offer the most promise in reducing fatigue severity/impact. Medline, EMBASE and PsycInfo electronic databases, amongst others, were searched through to August 2018. Thirty-four trials (12 exercise, 16 behavioural and 6 combined; n = 2,434 participants) met inclusion criteria. Data from 31 studies (n = 1,991 participants) contributed to the meta-analysis. Risk of bias (using the Cochrane tool) and study quality (GRADE) were assessed. The pooled (SMD) end-of-treatment effects on self-reported fatigue were: exercise interventions (n = 13) -.84 (95% CI -1.20 to -.47); behavioural interventions (n = 16) -.37 (95% CI -.53 to -.22); combined interventions (n = 5) -.16 (95% CI: -.36 to .04). Heterogeneity was high overall. Study quality was very low for exercise interventions and moderate for behavioural and combined interventions. Considering health care professional time, subgroup results suggest web-based cognitive behavioural therapy for fatigue, balance and/or multicomponent exercise interventions may be the cost-efficient therapies. These need testing in large RCTs with long-term follow-up to help define an implementable fatigue management pathway in MS.MS Society, U
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