431 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

    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

    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

    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

    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

    Prognostic Utility of Albumin-Bilirubin Grade for Short- and Long-Term Outcomes Following Hepatic Resection for Intrahepatic Cholangiocarcinoma: a Multi-Institutional Analysis of 706 Patients

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    Background: The objective of the current study was to define the impact of albumin-bilirubin (ALBI) grade on short- as well as long-term outcomes among patients with intrahepatic cholangiocarcinoma (ICC). Methods: Patients who underwent hepatectomy for ICC between 1990 and 2016 were identified using an international multi-institutional database. Clinicopathologic factors including ALBI score were assessed using bivariate and multivariable analyses, as well as standard survival analyses. Results: Among 706 patients, 453 (64.2%) patients had ALBI grade 1, 231 (32.7%) ALBI grade 2, and 22 (3.1%) had ALBI grade 3. After adjusting for all competing factors, patients with ALBI grade 2/3 had higher odds of a prolonged length-of-stay (>10 days, odds ratio [OR] = 2.37, 95% confidence interval [CI]:1.47-3.80), perioperative transfusion (OR = 2.15, 95% CI:1.45-3.18) and 90-day mortality (OR = 2.50, 95% CI:1.16-5.38). Median and 5-year overall survival (OS) for the entire cohort was 41.5 months (IQR:15.7-107.8) and 39.8%, respectively. Of note, median OS incrementally worsened with increased ALBI grade: grade 1, 49.6 months (IQR:18.3-NR) vs grade 2, 29.6 months (IQR:12.6-98.4) vs grade 3, 16.9 months (IQR:6.5-32.4; P < 0.001). On multivariable analysis, higher ALBI grade remained associated with higher hazards of death (grade 2/3: hazard ratio = 1.36, 95% CI:1.04-1.78). Conclusion: The ALBI score was associated with both short- and long-term outcomes following resection for ICC and could prove a useful surrogate marker to identify patients at risk for adverse outcomes.info:eu-repo/semantics/publishedVersio

    Natural history, phenotypic spectrum, and discriminative features of multisystemic RFC1 disease

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    Objective To delineate the full phenotypic spectrum, discriminative features, piloting longitudinal progression data, and sample size calculations of replication factor complex subunit 1 (RFC1) repeat expansions, recently identified as causing cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS). Methods Multimodal RFC1 repeat screening (PCR, Southern blot, whole-exome/genome sequencing?based approaches) combined with cross-sectional and longitudinal deep phenotyping in (1) cross-European cohort A (70 families) with ?2 features of CANVAS or ataxia with chronic cough (ACC) and (2) Turkish cohort B (105 families) with unselected late-onset ataxia. Results Prevalence of RFC1 disease was 67% in cohort A, 14% in unselected cohort B, 68% in clinical CANVAS, and 100% in ACC. RFC1 disease was also identified in Western and Eastern Asian individuals and even by whole-exome sequencing. Visual compensation, sensory symptoms, and cough were strong positive discriminative predictors (>90%) against RFC1-negative patients. The phenotype across 70 RFC1-positive patients was mostly multisystemic (69%), including dysautonomia (62%) and bradykinesia (28%) (overlap with cerebellar-type multiple system atrophy [MSA-C]), postural instability (49%), slow vertical saccades (17%), and chorea or dystonia (11%). Ataxia progression was ?1.3 Scale for the Assessment and Rating of Ataxia points per year (32 cross-sectional, 17 longitudinal assessments, follow-up ?9 years [mean 3.1 years]) but also included early falls, variable nonlinear phases of MSA-C?like progression (SARA points 2.5?5.5 per year), and premature death. Treatment trials require 330 (1-year trial) and 132 (2-year trial) patients in total to detect 50% reduced progression. Conclusions RFC1 disease is frequent and occurs across continents, with CANVAS and ACC as highly diagnostic phenotypes yet as variable, overlapping clusters along a continuous multisystemic disease spectrum, including MSA-C-overlap. Our natural history data help to inform future RFC1 treatment trials. Classification of Evidence This study provides Class II evidence that RFC1 repeat expansions are associated with CANVAS and ACC.FUNDING: Study Funding This work was supported via the European Union’s Horizon 2020 research and innovation program by the BMBF under the frame of the E-Rare-3 network PREPARE (01GM1607; to M. Synofzik,M.A., H.P., B.P.v.d.W.), by the DFG under the frame of EJP-RD network PROSPAX (No. 441409627; M. Synofzik, B.P.v.d.W., A.N.B.), and grant 779257 “Solve-RD” (toM. Synofzik, B.P.v.d.W.). B.P.v.d.W. receives additional research support from ZonMW, Hersenstichting, Gossweiler Foundation, uniQure, and Radboud University Medical Centre. T.B.H. was supported by the DFG (No 418081722). A.T. receives funding from the University of T¨ubingen, medical faculty, for the Clinician Scientist Program grant 439-0-0. A.C. thanks Medical Research Council, MR/T001712/1) and Fondazione CARIPLO (2019-1836) for grant support. L.S., T.K., B.P.v.d.W., and M. Synofzik are members of the European Reference Network for Rare Neurological Diseases, project 739510. A.N.B. is supported by the Suna and Inan Kirac Foundation and Koç University School of Medicine

    Natural History, Phenotypic Spectrum, and Discriminative Features of Multisystemic RFC1-disease

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    OBJECTIVE: To delineate the full phenotypic spectrum, discriminative features, piloting longitudinal progression data, and sample size calculations of RFC1-repeat expansions, recently identified as causing cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS). METHODS: Multimodal RFC1 repeat screening (PCR, southern blot, whole-exome/genome (WES/WGS)-based approaches) combined with cross-sectional and longitudinal deep-phenotyping in (i) cross-European cohort A (70 families) with ≥2 features of CANVAS and/or ataxia-with-chronic-cough (ACC); and (ii) Turkish cohort B (105 families) with unselected late-onset ataxia. RESULTS: Prevalence of RFC1-disease was 67% in cohort A, 14% in unselected cohort B, 68% in clinical CANVAS, and 100% in ACC. RFC1-disease was also identified in Western and Eastern Asians, and even by WES. Visual compensation, sensory symptoms, and cough were strong positive discriminative predictors (>90%) against RFC1-negative patients. The phenotype across 70 RFC1-positive patients was mostly multisystemic (69%), including dysautonomia (62%) and bradykinesia (28%) (=overlap with cerebellar-type multiple system atrophy [MSA-C]), postural instability (49%), slow vertical saccades (17%), and chorea and/or dystonia (11%). Ataxia progression was ∼1.3 SARA points/year (32 cross-sectional, 17 longitudinal assessments, follow-up ≤9 years [mean 3.1]), but also included early falls, variable non-linear phases of MSA-C-like progression (SARA 2.5-5.5/year), and premature death. Treatment trials require 330 (1-year-trial) and 132 (2-year-trial) patients in total to detect 50% reduced progression. CONCLUSIONS: RFC1-disease is frequent and occurs across continents, with CANVAS and ACC as highly diagnostic phenotypes, yet as variable, overlapping clusters along a continuous multisystemic disease spectrum, including MSA-C-overlap. Our natural history data help to inform future RFC1-treatment trials. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that RFC1-repeat expansions are associated with CANVAS and ACC
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