Search

Background & Aims There are limited data on patients with chronic HCV infection in whom combination voxilaprevir (VOX), velpatasvir (VEL), sofosbuvir (SOF) retreatment fails. Thus, we aimed to assess treatment failure and rescue treatment options in these patients. Methods Samples from 40 patients with HCV genotypes (GT) 1-4 in whom VOX/VEL/SOF retreatment failed were collected within the European Resistance Study Group. Population-based resistance analyses were conducted and clinical parameters and retreatment efficacies were evaluated retrospectively in 22 patients. Results Most VOX/VEL/SOF failure patients were infected with HCV GT3a (n = 18, 45%) or GT1a (n = 11, 28%) and had cirrhosis (n = 28, 70%). Previous treatments included an NS3-inhibitor (30%), an NS5A-inhibitor (100%) and SOF (85%). Baseline RAS data from a subgroup of patients before VOX/VEL/SOF retreatment (78%) showed few NS3 RASs apart from Q80K in GT1a (40%), typical NS5A RAS patterns in most patients (74%) and no S282T in NS5B. Sequencing after VOX/VEL/SOF failure was available in 98% of patients and showed only minor changes for NS3 and NS5A RASs. In 22 patients, rescue treatment was initiated with glecaprevir, pibrentasvir alone (n = 2) or with SOF±ribavirin (n = 15), VOX/VEL/SOF±ribavirin (n = 4) or VEL/SOF and ribavirin (n = 1) for 12 to 24 weeks. Sustained virologic response was achieved in 17/21 (81%) patients with a final treatment outcome. Of these, 2 GT3a-infected patients had virologic failure after rescue treatment with VEL/SOF or glecaprevir/pibrentasvir+SOF+ribavirin, and 2 patients with cirrhosis died during treatment or before reaching SVR12. Conclusions VOX/VEL/SOF failure was mainly observed in HCV GT3- and GT1a-infected patients with cirrhosis and was not associated with specific RAS patterns within NS3, NS5A or NS5B target regions. Rescue treatment with multiple targeted therapies was effective in most patients. Lay summary The advent of direct-acting antivirals has enabled the effective cure of chronic hepatitis C in most patients. However, treatment failure occurs in some patients, who are often retreated with a combination regimen called VOX/VEL/SOF, which is associated with very high rates of cure. However, VOX/VEL/SOF retreatment also fails in some patients. Herein, we analysed samples from patients in whom VOX/VEL/SOF retreatment failed and we assessed the efficacy of different rescue therapies, showing that rescue treatment is effective in most patients (81%).

The aim of this study was to define the breadth and specificity of dominant SARS-CoV-2-specific T cell epitopes using a comprehensive set of 135 overlapping 15-mer peptides covering the SARS-CoV-2 envelope (E), membrane (M) and nucleoprotein (N) in a cohort of 34 individuals with acute (n = 10) and resolved (n = 24) COVID-19. Following short-term virus-specific in vitro cultivation, the single peptide-specific CD4+ T cell response of each patient was screened using enzyme linked immuno spot assay (ELISpot) and confirmed by single-peptide intracellular cytokine staining (ICS) for interferon-γ (IFN-γ) production. 97% (n = 33) of patients elicited one or more N, M or E-specific CD4+ T cell responses and each patient targeted on average 21.7 (range 0–79) peptide specificities. Overall, we identified 10 N, M or E-specific peptides that showed a response frequency of more than 36% and five of them showed high binding affinity to multiple HLA class II binders in subsequent in vitro HLA binding assays. Three peptides elicited CD4+ T cell responses in more than 55% of all patients, namely Mem_P30 (aa146-160), Mem_P36 (aa176-190), both located within the M protein, and Ncl_P18 (aa86-100) located within the N protein. These peptides were further defined in terms of length and HLA restriction. Based on this epitope and restriction data we developed a novel DRB*11 tetramer (Mem_aa145-164) and examined the ex vivo phenotype of SARS-CoV-2-specific CD4+ T cells in one patient. This detailed characterization of single T cell peptide responses demonstrates that SARS-CoV-2 infection universally primes a broad T cell response directed against multiple specificities located within the N, M and E structural protein., Author summary The SARS-CoV-2 genome encodes for 25 different viral proteins. However, many immunological studies have focused on the immune response against the spike protein. This current study was designed to get a detailed understanding of the breadth and specificity of the CD4+ T cell response directed against the other structural proteins, namely the envelope (E), membrane (M) and nucleoprotein (N) using a comprehensive overlapping peptide set in a cohort of patients during early and resolved COVID-19. We detected a universally broad T cell response with on average more than 20 peptide responses per patient. Three peptides elicited CD4+ T cell responses in more than 55% of all patients, two located within the M protein, and one located within the N protein. These peptides were further defined in terms of length and HLA restriction, and we developed a novel MHC class II tetramer based on this data, which enabled us to investigate the ex vivo phenotype of SARS-CoV-2-specific CD4+ T cells in one patient. This large immunological data set on individual immune responses will be useful for further detailed studies on the immunopathogenesis of SARS-CoV-2 infection and vaccine design.

A calibration routine is presented for an array of retarding field energy analyzer (RFEA) sensors distributed across a planar electrode surface with a diameter of 450 mm that is exposed to a low temperature plasma. Such an array is used to measure the ion velocity distribution function at the electrode with radial and azimuthal resolutions as a basis for knowledge-based plasma process development. The presented calibration procedure is tested by exposing such an RFEA array to a large-area capacitively coupled argon plasma driven by two frequencies (13.56 and 27.12 MHz) at a gas pressure of 0.5 Pa. Up to 12 sensors are calibrated with respect to the 13th sensor, called the global reference sensor, by systematically varying the sensor positions across the array. The results show that the uncalibrated radial and azimuthal ion flux profiles are incorrect. The obtained profiles are different depending on the sensor arrangement and exhibit different radial and azimuthal behaviors. Based on the proposed calibration routine, the ion flux profiles can be corrected and a meaningful interpretation of the measured data is possible. The calibration factors are almost independent of the external process parameters, namely, input power, gas pressure, and gas mixture, investigated under large-area single-frequency capacitively coupled plasma conditions (27.12 MHz). Thus, mean calibration factors are determined based on 45 different process conditions and can be used independent of the plasma conditions. The temporal stability of the calibration factors is found to be limited, i.e., the calibration must be repeated periodically.

Background: γδ T cells represent a unique T cell subpopulation due to their ability to recognize cancer cells in a T cell receptor- (TCR) dependent manner, but also in a non-major histocompatibility complex- (MHC) restricted way via natural killer receptors (NKRs). Endowed with these features, they represent attractive effectors for immuno-therapeutic strategies with a better safety profile and a more favorable anti-tumor efficacy in comparison to conventional αβ T cells. Also, remarkable progress has been achieved re-activating exhausted T lymphocytes with inhibitors of co-regulatory receptors e.g., programmed cell death protein 1 (PD-1), T cell immunoreceptor with Ig and ITIM domains (TIGIT) and of the adenosine pathway (CD39, CD73). Regarding γδ T cells, little evidence is available. This study aimed to immunophenotypically characterize γδ T cells from patients with diagnosed acute myeloid leukemia (AML) in comparison to patients with multiple myeloma (MM) and healthy donors (HD).Methods: The frequency, differentiation, activation, and exhaustion status of bone marrow- (BM) derived γδ T cells from patients with AML (n = 10) and MM (n = 11) were assessed in comparison to corresponding CD4+ and CD8+ T cells and peripheral blood- (PB) derived γδ T cells from HDs (n = 16) using multiparameter flow cytometry.Results: BM-infiltrating Vδ1 T cells showed an increased terminally differentiated cell population (TEMRAs) in AML and MM in comparison to HDs with an aberrant subpopulation of CD27−CD45RA++ cells. TIGIT, PD-1, TIM-3, and CD39 were more frequently expressed by γδ T cells in comparison to the corresponding CD4+ T cell population, with expression levels that were similar to that on CD8+ effector cells in both hematologic malignancies. In comparison to Vδ2 T cells, the increased frequency of PD-1+-, TIGIT+-, TIM-3+, and CD39+ cells was specifically observed on Vδ1 T cells and related to the TEMRA Vδ1 population with a significant co-expression of PD-1 and TIM-3 together with TIGIT.Conclusion: Our results revealed that BM-resident γδ T cells in AML and MM express TIGIT, PD-1, TIM-3 and CD39. As effector population for autologous and allogeneic strategies, inhibition of co-inhibitory receptors on especially Vδ1 γδ T cells may lead to re-invigoration that could further increase their cytotoxic potential.

Cr-Al-N thin film materials libraries were synthesized by combinatorial reactive high power impulse magnetron sputtering (HiPIMS). Different HiPIMS repetition frequencies and peak power densities were applied altering the ion to growth flux ratio. Moreover, time-resolved ion energy distribution functions were measured with a retarding field energy analyzer (RFEA). The plasma properties were measured during the growth of films with different compositions within the materials library and correlated to the resulting film properties such as phase, grain size, texture, indentation modulus, indentation hardness, and residual stress. The influence of the ion to growth flux ratio on the film properties was most significant for films with high Al-content (xAl = 50 at. %). X-ray diffraction with a 2D detector revealed hcp-AlN precipitation starting from Al-concentration xAl ≥ 50 at. %. This precipitation might be related to the kinetically enhanced adatom mobility for a high ratio of ions per deposited atoms, leading to strong intermixing of the deposited species. A structure zone transition, induced by composition and flux ratio JI/JG, from zone T to zone Ic structure was observed which hints toward the conclusion that the combination of increasing flux ratio and Al-concentration lead to opposing trends regarding the increase in homologous temperature.

Direct‐acting antiviral (DAA) therapies have revolutionized the treatment of chronic hepatitis C virus infection, achieving sustained virological response (SVR) rates of >90% even in patients with advanced liver cirrhosis. Having observed an unusual case of repeated DAA therapy failures in a patient with a transjugular intrahepatic portosystemic shunt (TIPS), we assessed a possible association between prior TIPS placement and DAA failure. A structured search of our clinical database revealed 10 patients who had received DAA therapy after TIPS placement. At the time of therapy, most patients (8; 80%) presented with a Child‐Pugh score B, and the following DAA regimens were used: sofosbuvir/ledipasvir ± ribavirin (5 patients), sofosbuvir/daclatasvir ± ribavirin (3), sofosbuvir/velpatasvir (2), and sofosbuvir/velpatasvir/voxilaprevir (1). In total, 5 patients (50%) achieved an SVR, whereas a virological relapse occurred in the other half of the cases, including 2 patients with multiple relapses. In this patient cohort, SVR rates were unusually low for all regimens: sofosbuvir/ledipasvir ± ribavirin, 3/5 (60%); sofosbuvir/daclatasvir ± ribavirin, 2/3 (66%); sofosbuvir/velpatasvir, 0/2 (0%); and sofosbuvir/velpatasvir/voxilaprevir, 0/1 (0%), and patients with a TIPS made up a relevant proportion of DAA failures in patients with cirrhosis at our center: sofosbuvir/ledipasvir, 2/18 (11%); sofosbuvir/daclatasvir, 1/4 (25%); sofosbuvir/velpatasvir, 2/3 (66%); and sofosbuvir/velpatasvir/voxilaprevir, 1/1 (100%). Conclusion: We observed a high rate of virological relapse in patients with a TIPS who received DAA treatment and therefore postulate that TIPS placement may be a possible risk factor for DAA failure due to the profound hemodynamic changes evoked by the intervention. Longer treatment duration or addition of ribavirin might be warranted in these patients.

Overwhelming activation of T cells in acute malaria is associated with severe outcomes. Thus, counter-regulation by anti-inflammatory mechanisms is indispensable for an optimal resolution of disease. Using Plasmodium berghei ANKA (PbA) infection of C57BL/6 mice, we performed a comprehensive analysis of co-inhibitory molecules expressed on CD4+ and CD8+ T cells using an unbiased cluster analysis approach. We identified similar T cell clusters co-expressing several co-inhibitory molecules like programmed cell death protein 1 (PD-1) and lymphocyte activation gene 3 (LAG-3) in the CD4+ and the CD8+ T cell compartment. Interestingly, despite expressing co-inhibitory molecules, which are associated with T cell exhaustion in chronic settings, these T cells were more functional compared to activated T cells that were negative for co-inhibitory molecules. However, T cells expressing high levels of PD-1 and LAG-3 also conferred suppressive capacity and thus resembled type I regulatory T cells. To our knowledge, this is the first description of malaria-induced CD8+ T cells with suppressive capacity. Importantly, we found an induction of T cells with a similar co-inhibitory rich phenotype in Plasmodium falciparum infected patients. In conclusion, we demonstrate that malaria-induced T cells expressing co-inhibitory molecules are not exhausted, but acquire additional suppressive capacity, which might represent an immune regulatory pathway to prevent further activation of T cells during acute malaria.

In patients with hepatitis E virus (HEV) infections, extrahepatic, particularly renal and hematological manifestations, are increasingly reported in the medical literature but have never been studied compared to a control cohort. We retrospectively analyzed medical records of consecutive patients that were diagnosed with acute hepatitis E (AHE) (n = 69) or acute hepatitis A (AHA) (n = 46) at the University Medical Center Hamburg Eppendorf from January 2009 to August 2019 for demographical, clinical, and laboratory information. Patients with AHE had significantly lower median levels of ALAT (798 U/L) and total bilirubin (1.8 mg/dL) compared to patients with AHA (2326 U/L, p &lt, 0.001 and 5.2 mg/dL, 0.001), suggesting a generally less severe hepatitis. In contrast, patients with AHE had significantly higher median serum creatinine levels (0.9 mg/dL vs. 0.8 mg/dL, p = 0.002) and lower median estimated glomerular filtration rate (eGFR) (91 mL/min/1.73 m2 vs. 109 mL/min/1.73 m2, 0.001) than patients with AHA. Leucocyte, neutrophil and lymphocyte count, hemoglobin, platelets, red cell distribution width (RDW), neutrophil to lymphocyte ratio (NLR), and RDW to lymphocyte ratio (RLR) did not differ between patients with AHE and those with AHA. Our observations indicate that renal but not hematological interference presents an underrecognized extrahepatic feature of AHE, while inflammation of the liver seems to be more severe in AHA.

A zero-dimensional (volume-averaged) and a pseudo-one-dimensional plug-flow (spatially resolved) model are developed to investigate atmospheric-pressure plasma jets operated with He, He/O2, He/N2 and He/N2/O2 mixtures. The models are coupled with the Boltzmann equation under the two-term approximation to self-consistently calculate the electron energy distribution function. An agreement is obtained between the zero-dimensional model calculations and the spatially averaged values of the plug-flow simulation results. The zero-dimensional model calculations are verified against spatially resolved simulation results and validated against a wide variety of measurement data from the literature. The nitric oxide (NO) concentration is thoroughly characterized for a variation of the gas mixture ratio, helium flow rate and absorbed power. An ‘effective’ and a hypothetical larger rate coefficient value for the reactive quenching N 2 ( A 3 Σ , B 3 Π ) + O ( P 3 ) → N O + N ( D 2 ) are used to estimate the role of the species N2(A3Σ, B3Π; v > 0) and multiple higher N2 electronically excited states instead of only N2(A3Σ, B3Π; v = 0) in this quenching. The NO concentration measurements at low power are better and almost identically captured by the simulations using the ‘effective’ and hypothetical values, respectively. Furthermore, the O ( P 3 ) density measurements under the same operation conditions are also better predicted by the simulations adopting these values. It is found that the contribution of the vibrationally excited nitrogen molecules N2(v ⩾ 13) to the net NO formation rate gains more significance at higher power. The vibrational distribution functions (VDFs) of molecular oxygen O2(v < 41) and nitrogen N2(v < 58) are investigated regarding their formation mechanisms and their responses to the variation of operation parameters. It is observed that the N2 VDF shows a stronger response than the O2 VDF. The sensitivity of the simulation results with respect to a variation of the VDF resolutions, wall reaction probabilities and synthetic air impurity levels is presented. The simulated plasma properties are sensitive to the variation, especially for a feed gas mixture containing nitrogen. The plug-flow model is validated against one-dimensional experimental data in the gas flow direction, and it is only used in case an analysis of the spatially resolved plasma properties inside the jet chamber is of interest. The increasing NO spatial concentration in the gas flow direction is saturated at a relatively high power. A stationary O2 VDF is obtained along the direction of the mass flow, while a continuously growing N2 VDF is observed until the jet nozzle.

We provide detailed clinical, virological, and immunological data of a B-cell–depleted patient treated with obinutuzumab for follicular lymphoma with protracted coronavirus disease 2019 (COVID-19) and viremia. A sustained response was achieved after 2 courses of remdesivir and subsequent convalescent plasma therapy. Immunocompromised patients might require combined and prolonged antiviral treatment regimens.

The ectoenzymes CD39 and CD73 play a major role in controlling tissue inflammation by regulating the balance between adenosine triphosphate (ATP) and adenosine. Still, little is known about the role of these two enzymes and ATP and its metabolites in the pathophysiology of inflammatory bowel disease (IBD). We isolated mononuclear cells from peripheral blood and lamina propria of the large intestine of patients diagnosed with IBD and of healthy volunteers. We then comprehensively analyzed the CD39 and CD73 expression patterns together with markers of activation (HLA-DR, CD38), differentiation (CCR7, CD45RA) and tissue-residency (CD69, CD103, CD49a) on CD4+, CD8+, γδ+ T cells and mucosa-associated invariant T cells using flow cytometry. CD39 expression levels of γδ+ and CD8+ T cells in lamina propria lymphocytes (LPL) were much higher compared to peripheral blood mononuclear cells. Moreover, the frequency of CD39+ CD4+ and CD8+, but not γδ+ LPL positively correlated with T-cell activation. The frequency of CD39+ cells among tissue-resident memory LPL (Trm) was higher compared to non-Trm for all subsets, confirming that CD39 is a marker for the tissue-resident memory phenotype. γδ+ Trm also showed a distinct cytokine profile upon stimulation – the frequency of IFN-γ+ and IL-17A+ cells was significantly lower in γδ+ Trm compared to non-Trm. Interestingly, we observed a decreased frequency of CD39+ γδ+ T cells in IBD patients compared to healthy controls (p = 0.0049). Prospective studies need to elucidate the exact role of this novel CD39+ γδ+ T-cell population with tissue-resident memory phenotype and its possible contribution to the pathogenesis of IBD and other inflammatory disorders.

This study aimed to characterize different natural killer (NK) cell phenotypes on bone marrow and peripheral blood cells from acute myeloid leukemia (AML) patients and healthy donors (HDs). Our data show that CD56dimCD16− and CD56brightCD16− NK cells represent the predominant NK cell subpopulations in AML, while the CD56dimCD16+ NK cells are significantly reduced compared to HDs. Moreover, TIGIT+ and PVRIG+ cells cluster on the CD56dimCD16+ subset whereas CD39+ and CD38+ cells do so on CD56brightCD16− NK cells in AML. Furthermore, functional effects of (co-)blockade of TIGIT and CD39 or A2AR on NK cell functionality were analyzed. These experiments revealed that the single blockade of the TIGIT receptor results in an increased NK-92 cell-mediated killing of AML cells in vitro. Combined targeting of CD39 or A2AR significantly augments the anti-TIGIT-mediated lysis of AML cells. Our data indicate that distinct NK cell subsets in AML exhibit different immunosuppressive patterns (via the TIGIT/PVRIG receptors and the purinergic pathway). In summary, we conclude that TIGIT, CD39, and A2AR constitute relevant inhibitory checkpoints of NK cells in AML patients. A combinatorial blockade synergistically strengthens NK-92 cell-mediated cytotoxicity. As inhibitors of TIGIT, CD39, and A2AR are clinically available, studies on their combined use could be conducted in the near future.

Background: Bidirectional interactions between the tumor microenvironment (TME) and AML cells lead to disease progression through induction of angiogenesis, migration, cancer stemness and local immunosuppression. Leukemia-associated macrophages (LAM) constitute an important cell population within the TME, but little is known about the phenotype, function, and plasticity of these cells. In the present study we provide an extensive characterization of the macrophage population in patients with AML. Methods: The phenotype and expression of co-regulatory receptors was assessed on different bone marrow-derived CD68 +CD14 + LAM populations, in comparison to corresponding CD3 + T-cells and CD117 +CD34 + AML cells (n=35), as well as peripheral blood monocytes from healthy donors (HD, n=16) using multi-parameter flow cytometry. The expression of surface markers and the distribution of LAM subpopulations was correlated with clinical parameters. The effect of a blocking anti-TIGIT antibody on the in vitro plasticity on primary LAMs and monocyte-derived macrophages from healthy donors was investigated. Furthermore, we analyzed if the treatment with blocking anti-TIGIT and anti-CD47 antibodies could increase the anti-leukemic phagocytosis of AML cell lines and in vitro polarized monocyte-derived M2 macrophages. Results: Phenotypic analysis of M1 and M2 macrophages in AML and HD revealed that the predominant macrophage population in patients with AML is made up of immunosuppressive alternatively activated M2 LAMs defined by expression of CD163 and CD86 (M1 AML vs. HD p Importantly, in vitro blockade of TIGIT in primary LAMs of AML patients or differentiated PB-derived M2 macrophages of HDs resulted in a change in polarization from the M2 towards the M1 phenotype after 24 hours (AML: anti-TIGIT vs. IgG2a p Moreover, the additional blockade of TIGIT on PB-derived M2 macrophages augmented the anti-CD47-mediated phagocytosis of the AML cell lines MOLM-13 and MV4-11 after 4 hours (MOLM-13: anti-CD47 vs. IgG1a 31% vs. 10.9%, p=0.04; anti-CD47 vs. combined anti-CD47 + anti-TIGIT 31% vs. 46.4%, p Next, we correlated the phenotypic data with clinical parameters. AML patients of the intermediate risk group according to ELN criteria exhibited a significantly higher frequency of M2 LAMs co-expressing TIGIT and LAG-3 than those in the favorable group (p=0.04 and p=0.01). Moreover, the frequency of TIM-3 + M2 LAMs was significantly increased in patients with adverse and intermediate risk in comparison to those with a favorable risk (p=0.01, p=0.0053). Furthermore, TIGIT + M2 LAMs were significantly more frequent in patients with the FLT3 ITD mutation in comparison with the wilde type (p=0.03). Conclusions: Our findings suggest that the proven clinical effect of monoclonal antibodies against TIGIT and TIM-3 in cancer may be due in part to their action on macrophages and depend on macrophage polarization. Our study identifies TIGIT + M2 LAMs co-expressing TIM-3 and LAG-3 as a promising effector population in AML. Further experiments should be conducted to investigate macrophage-mediated cytotoxicity in AML. Disclosures Brauneck: Daiichi Sankyo: Consultancy, Honoraria, Other: meeting attendance; Servier: Consultancy, Honoraria, Other: meeting attendance; Jazz Pharmaceuticals: Other: meeting attendance; Novartis: Other: meeting attendance. Bokemeyer: BMS: Honoraria, Other: Travel accomodation, Research Funding; Sanofi: Consultancy, Honoraria, Other: Travel accomodation; Merck Serono: Consultancy, Other: Travel accomodation ; Bayer Schering Pharma: Consultancy; GSO: Consultancy; AOK Health insurance: Consultancy; Abbvie: Research Funding; ADC Therapeutics: Research Funding; Agile Therapeutics: Research Funding; Alexion Pharmaceuticals: Research Funding; Amgen: Research Funding; Apellis Pharmaceuticals: Research Funding; Astellas: Research Funding; BerGenBio: Research Funding; Blueprint Medicine: Research Funding; Boehringer Ingelheim: Research Funding; Celgene: Research Funding; Daiichi Sankyo: Research Funding; Eisai: Research Funding; Gilead Sciences: Research Funding; Gylcotope GmbH: Research Funding; GlaxoSmithKline: Research Funding; Inside: Research Funding; IO Biotech: Research Funding; Isofol Medical: Research Funding; Janssen-Cilag: Research Funding; Karyopharm Therapeutics: Research Funding; Lilly: Research Funding; Millenium: Research Funding; MSD: Research Funding; Merck KGaA: Honoraria; Bayer: Honoraria, Research Funding; Roche: Honoraria, Research Funding; Merck Sharp Dohme: Consultancy, Honoraria; AstraZeneca: Honoraria, Research Funding; Lilly/ImClone: Consultancy; Nektar: Research Funding; Rafael Pharmaceuticals: Research Funding; Springworks Therapeutics: Research Funding; Taiho Pharmaceutical: Research Funding; Pfizer: Other. Fiedler: Celgene: Consultancy; Servier: Consultancy, Other: support for meeting attendance; Abbvie: Consultancy, Honoraria; Morphosys: Consultancy; Pfizer: Consultancy, Research Funding; Daiichi Sankyo: Consultancy, Other: support for meeting attendance; Jazz Pharmaceuticals: Consultancy, Other: support for meeting attendance; Stemline: Consultancy; Novartis: Consultancy; ARIAD/Incyte: Consultancy; Amgen: Consultancy, Other: support for meeting attendance, Patents & Royalties, Research Funding.

A rf magnetized double ring-shaped hollow cathode plasma with permanent magnets has been developed for high-density hydrogen plasma generation at various hydrogen gas pressures, pH2. The discharge breakdown voltage with magnet decreases with increasing pH2 and is lower than that without magnet at 1 ≤ pH2 ≤ 30 Pa and is otherwise higher than that. Spatial distributions of the ion saturation current density have also been investigated at various hydrogen gas pressures of pH2 = 5, 10, 20, 30 and 40 Pa. The high-density double peaks of the ion density due to the double ring-shaped hollow trenches are observed near the hollow electrode at pH2 ≥ 10 Pa. The laterally uniform high-density hydrogen plasma with a density of 1011cm−3 is attained at the distance z = 30 mm from the electrode under low gas pressure of 5 Pa and 10 Pa at rf power of 60 W.

External magnetic fields impose diverse effects on low-temperature plasmas. We study these in a low-pressure capacitively coupled radio frequency plasma in argon via self-consistent kinetic simulations. The primary effect of the transversal magnetic field, that manifests itself in the trapping of electrons at lower excitation frequencies and, thus, in an increase of the plasma density as a function of the magnetic field, is overruled at higher excitation frequencies by the attenuation of the self-excitation of the Plasma Series Resonance oscillations and the attenuation of the Non-Linear Electron Resonance Heating, which lead to a reduced plasma density. At higher magnetic fields the plasma density increases again due to (i) a longer interaction time between the electrons and the edges of the expanding sheaths and (ii) the electric field reversals that develop at the collapsing sheath edges to overcome the trapping of electrons and accelerate them towards the electrodes.

In the present work two subclasses of the human antibody Immunoglobulin G (IgG) have been investigated by Small-Angle X-ray Scattering under high hydrostatic pressures up to 5kbar. It is shown that IgG adopts a symmetric T-shape in solution which differs significantly from available crystal structures. Moreover, high-pressure experiments verify the high stability of the IgG molecule. It is not unfolded by hydrostatic pressures of up to 5kbar but a slight increase of the radius of gyration was observed at elevated pressures.

Supplemental Digital Content is available in the text, The aim of this retrospective cohort study was to compare safety, efficacy and rates and reasons of discontinuation of the 3 currently approved integrase strand transfer inhibitors (INSTIs) elvitegravir (EVG), dolutegravir (DTG), and raltegravir (RAL) in HIV-infected treatment-naïve and -experienced patients in a real-world cohort. One hundred four treatment-naïve patients were prescribed an INSTI-based combined antiretroviral therapy (cART)-regimen (first-line group) and 219 patients were switched to an INSTI-based cART-regimen from another treatment regimen (switch group) at our institution between May 2007 and December 2014. Twelve months after initiation of treatment, 92% of patients in the first-line group (EVG: 96%, n = 22/23; DTG: 92%, n = 34/37; RAL: 90%, n = 28/31) and 88% of patients in the switch group (EVG: 94%, n = 32/34; DTG: 90%, n = 69/77; RAL: 85%, n = 67/79) showed full virological suppression (viral load

Every year, there are an estimated 20 million hepatitis E virus (HEV) infections worldwide, leading to an estimated 3.3 million symptomatic cases of hepatitis E. HEV is largely circulating in the west and is associated with several hepatic and extrahepatic diseases. HEV Genotype 1 and 2 infections are waterborne and causative for epidemics in the tropics, while genotype 3 and 4 infections are zoonotic diseases and are mainly transmitted by ingestion of undercooked pork in industrialized nations. The clinical course of these infections differs: genotype 1 and 2 infection can cause acute illness and can lead to acute liver failure (ALF) or acute on chronic liver failure (ACLF) with a high mortality rate of 20% in pregnant women. In contrast, the majority of HEV GT-3 and -4 infections have a clinically asymptomatic course and only rarely lead to acute on chronic liver failure in elderly or patients with underlying liver disease. Immunosuppressed individuals infected with genotype 3 or 4 may develop chronic hepatitis E, which then can lead to life-threatening cirrhosis. Furthermore, several extra-hepatic manifestations affecting various organs have been associated with ongoing or previous HEV infections but the causal link for many of them still needs to be proven. There is no approved specific therapy for the treatment of acute or chronic HEV GT-3 or -4 infections but off-label use of ribavirin has been demonstrated to be safe and effective in the majority of patients. However, in approximately 15% of chronically HEV infected patients, cure is not possible.

Packed-bed plasma reactors (PBPRs) have been investigated extensively to study the abatement of volatile organic compounds such as toluene. Previous studies have reported that the applied voltage (or power) is a critical parameter that affects the performance of PBPRs. However, the origin of this change in performance is not well understood. A conventional PBPR contains irregularly filled dielectric pellets that generate several micro- and mesoscopic voids in between the pellets and between pellets and dielectric walls where filamentary discharges are generated. These voids are optically inaccessible and the reaction products are often generated in gaseous form; therefore, the location of the chemical reactions within these voids could not be studied. In this work, we have qualitatively investigated the influence of the applied voltage on the locations of chemical reactions in the void using toluene oxidation as an example. Using a single layer of regularly arranged hemispherical pellets and a transparent electrode in a PBPR, the plasma generation within these voids became optically accessible. The operating conditions were tailored to enhance the deposition of solid or liquid products on the glass beads to understand the locations of chemical reactions. The intensified charged coupled device camera images of the discharge through the transparent electrode show that the distribution of plasma emission changes with the applied voltage amplitude. The distribution of the deposited/condensed solid/liquid intermediates and reaction products was found to match the plasma emission. The analysis of the reaction products and deposition/condensation locations indicates that short-living species such as energetic electrons, OH and O radicals might play an essential role in the formation of deposited chemicals on the glass beads.

Hepatitis C virus infection is causing chronic liver disease, cirrhosis, and hepatocellular carcinoma. By combining direct-acting antivirals (DAAs), high sustained virologic response rates (SVRs) can be achieved. Resistance-associated substitutions (RASs) are commonly observed after DAA failure, and especially nonstructural protein 5A (NS5A) RASs may impact retreatment options.1-3 Data on retreatment of DAA failure patients using first-generation DAAs are limited.4-7 Recently, a second-generation protease- and NS5A-inhibitor plus sofosbuvir (voxilaprevir/velpatasvir/sofosbuvir [VOX/VEL/SOF]) was approved for retreatment after DAA failure.8 However, this and other second-generation regimens are not available in many resource-limited countries or are not reimbursed by regular insurance, and recommendations regarding the selection of retreatment regimens using first-generation DAAs are very important. This study aimed to analyze patients who were re-treated with first-generation DAAs after failure of a DAA combination therapy.

We present a spatio-temporally resolved analysis of electron power absorption in capacitively coupled argon plasmas at low pressures (1–10 Pa), based on the 1D momentum balance equation embedded into 1d3v particle-in-cell/Monte Carlo collisions simulations. In contrast to the predictions of theoretical models we find ‘Ohmic heating’ to be the dominant electron power absorption mechanism on time average at the lowest pressures, and not ‘stochastic’ or ‘Pressure heating’. The cause for this is identified to be the attenuation of electron power absorption due to electron acceleration by the ‘ambipolar’ electric field on time average at low pressure, which is a consequence of the collisionless transit of energetic beam electrons generated during sheath expansion at one electrode to the opposite electrode. At such conditions, these energetic electrons arrive during the local sheath collapse and can be lost to the surface, thereby reducing the plasma density and creating a temporally more symmetric electron temperature within the radio frequency (RF) period compared to that in discharges operated at higher pressures. The more symmetric temperature profile causes a reduction of ‘Pressure heating’ on time average. The latter is reduced further, even to negative values, by the attenuation of the ‘ambipolar’ electric field at each electrode during the local sheath collapse, which is a consequence of the temporal modulation of the electron density profile within the RF period, observed at the lowest pressures studied.

Spatially resolved tunable diode-laser absorption measurements of the absolute densities of He-I (23S1) metastables in a micro atmospheric pressure plasma jet operated in He/N2 and driven by ‘peaks’- and ‘valleys’-type tailored voltage waveforms are presented. The measurements are performed at different nitrogen admixture concentrations and peak-to-peak voltages with waveforms that consist of up to four consecutive harmonics of the fundamental frequency of 13.56 MHz. Comparisons of the measured metastable densities with those obtained from particle-in-cell/Monte Carlo collision simulations show a good quantitative agreement. The density of helium metastables is found to be significantly enhanced by increasing the number of consecutive driving harmonics. Their generation can be further optimized by tuning the peak-to-peak voltage amplitude and the concentration of the reactive gas admixture. These findings are understood based on detailed fundamental insights into the spatio-temporal electron dynamics gained from the simulations, which show that voltage waveform tailoring allows to control the electron energy distribution function to optimize the metastable generation. A high degree of correlation between the metastable creation rate and the electron impact excitation rate from the helium ground state into the He-I ((3s)3S1) level is observed for some conditions which may facilitate an estimation of the metastable densities based on phase resolved optical emission spectroscopy measurements of the 706.5 nm He-I line originating from the above level and metastable density values at proper reference conditions.

Background Type III interferons (IFNs) (λ1–3) activate similar signaling cascades as type I IFNs (α and β) via different receptors. Since IFN-α and lymphotoxin-β activate cytosine deamination and subsequent purging of nuclear hepatitis B virus (HBV) DNA, we investigated whether IFN-β and -λ may also induce these antiviral effects in differentiated HBV-infected hepatocytes. Methods After determining the biological activity of IFN-α2, -β1, -λ1, and -λ2 in differentiated hepatocytes, their antiviral effects were analyzed in HBV-infected primary human hepatocytes and HepaRG cells. Results Type I and III IFNs reduced nuclear open-circle DNA and covalently closed circular DNA (cccDNA) levels in HBV-infected cells. IFN-β and -λ were at least as efficient as IFN-α. Differential DNA-denaturing polymerase chain reaction and sequencing analysis revealed G-to-A sequence alterations of HBV cccDNA in IFN-α, -β, and -λ–treated liver cells indicating deamination. All IFNs induced apolipoprotein B messenger RNA–editing enzyme–catalytic polypeptide-like (APOBEC) deaminases 3A and 3G within 24 hours of treatment, but IFN-β and -λ induced longer-lasting expression of APOBEC deaminases in comparison to IFN-α. Conclusions IFN-β, IFN-λ1, and IFN-λ2 induce cccDNA deamination and degradation at least as efficiently as IFN-α, indicating that these antiviral cytokines are interesting candidates for the design of new therapeutic strategies aiming at cccDNA reduction and HBV cure.

There are only limited data on sofosbuvir-based treatment regimens in hepatitis C virus (HCV) genotype 4-infected patients.To evaluate safety and efficacy of sofosbuvir-based triple-therapy in HCV genotype 4 infection.All HCV genotype 4-infected patients who started sofosbuvir-based triple-therapy at our two centres between January and June 2014 were prospectively included (N=24) and compared to genotype 4 patients treated with peginterferon/ribavirin between January 2001 and December 2012 (N=63).The demographics in the sofosbuvir group and the controls were comparable (males 87.5% and 82.5%; mean age 46.7±9.0 years and 42.0±9.8 years, respectively). Sustained virological response was achieved in 83.3% in the sofosbuvir group and in 47.6% of controls (P=0.003). Fatigue (P=0.007), flu-like (P=0.015), gastrointestinal (P0.001), dermatologic (P0.001) and psychiatric symptoms (P=0.022) were more common in the control group.In our real-life cohort, sofosbuvir-based triple therapy confirmed its high efficacy and safety for chronic genotype 4 hepatitis C.

A capacitively coupled hydrogen diluted silane discharge operated at pressures above 500 Pa and driven by a combination of 13.56 MHz and 27.12 MHz is investigated by infrared laser absorption spectroscopy. Adjusting the phase angle between the two applied frequencies enables the control of the discharge symmetry via the Electrical Asymmetry Effect (EAE). The absorption measurements prove that the degree of dissociation of SiH 4 and, thus, the radical flux remains approximately constant, independently of the phase angle. Furthermore, the results show that the DC self-bias can be adjusted by tuning the phase, so that the sheath voltages change. Thus, the ion properties at the electrodes can be controlled via the EAE. This has an effect on the deposition of thin films, which are grown on glass substrates at various phase angles and analyzed using Raman spectrometry: Reducing the ion energy at the substrate leads to a decrease of the amorphous fraction in the predominantly microcrystalline film.

There are limited data regarding the real world effectiveness of direct acting antivirals (DAA) for the therapy of chronic genotype 3 hepatitis C virus (HCV) infection. All HCV genotype 3 infected patients from the German hepatitis C cohort (GECCO), which is a prospective database of nine German hepatitis C treatment centers, were included in the study. 342 chronically infected HCV genotype 3 patients were analyzed (253 males [74.0%], mean age 47.3 years, 127 cirrhotic patients [37.1%] mostly with Child A cirrhosis, 113 treatment experienced patients [37.1%], 38 HCV/HIV co-infected patients [11.1%]). SVR12 rates in the “intention-to-treat” analysis were as follows: sofosbuvir/ribavirin 69.4% (75/108), sofosbuvir/peginterferon/ribavirin 80.6% (58/72), sofosbuvir/daclatasvir ± ribavirin for 12 weeks 88.3% (53/63), sofosbuvir/daclatasvir ± ribavirin for 24 weeks 79.3% (23/29), sofosbuvir/ledipasvir ± ribavirin for 12 weeks 71.4% (10/14) and sofosbuvir/ledipasvir ± ribavirin for 24 weeks 86.7% (26/30). Forty patients were lost to follow-up, 23 patients had a relapse, 4 patients stopped treatment prematurely and 1 patient died. Female sex (P = 0.038) and treatment with two different DAAs (P = 0.05) were predictors for SVR12 in the multivariate analysis. In conclusion, sofosbuvir/daclatasvir ± ribavirin for 12 weeks and sofosbuvir/ledipasvir ± ribavirin for 24 weeks are effective for the treatment of HCV genotype 3 infected patients including cirrhotic, treatment-experienced or HIV/HCV co-infected patients. This article is protected by copyright. All rights reserved

Classical dual-frequency capacitively coupled plasmas (2f CCPs) operating at low pressures and significantly different frequencies are often used for a variety of applications in semiconductor manufacturing in order to control the mean ion energy at the electrodes separately from the ion flux. However, recent computational studies have indicated that this separate control is limited by the frequency coupling effects and by the contribution of secondary electrons to the ionization dynamics [Donko et al., Appl. Phys. Lett. 97, 081501 (2010); Schulze et al., Plasma Sources Sci. Technol. 20, 045007 (2011)]. Here, we verify these simulation results experimentally by measuring the ion flux to an electrode as a function of the low frequency (LF) and high frequency power at different neutral gas pressures in a 2f CCP operated at 2.26 MHz and 13.56 MHz in argon. In agreement with previous computational predictions, we find the ion flux to decrease as a function of the LF power at a low pressure of 1 mTorr due to the frequency coupling and to increase as a function of the LF power at a higher pressure of 60 mTorr due to the presence of secondary electrons. These experimental findings show that separate control of ion properties in classical 2f CCPs is generally not possible, but potentially limited to specific discharge conditions.Classical dual-frequency capacitively coupled plasmas (2f CCPs) operating at low pressures and significantly different frequencies are often used for a variety of applications in semiconductor manufacturing in order to control the mean ion energy at the electrodes separately from the ion flux. However, recent computational studies have indicated that this separate control is limited by the frequency coupling effects and by the contribution of secondary electrons to the ionization dynamics [Donko et al., Appl. Phys. Lett. 97, 081501 (2010); Schulze et al., Plasma Sources Sci. Technol. 20, 045007 (2011)]. Here, we verify these simulation results experimentally by measuring the ion flux to an electrode as a function of the low frequency (LF) and high frequency power at different neutral gas pressures in a 2f CCP operated at 2.26 MHz and 13.56 MHz in argon. In agreement with previous computational predictions, we find the ion flux to decrease as a function of the LF power at a low pressure of 1 mTorr due to t...

Particle-in-Cell/Monte Carlo Collision simulations are performed to investigate the effects of heavy-particle induced secondary electrons (SEs) on the ionization dynamics and on the control of ion properties at the electrodes in geometrically symmetric capacitively coupled argon discharges driven by tailored voltage waveforms. The driving voltage waveform is composed of a maximum of four ( 1≤N≤4) consecutive harmonics of the fundamental frequency of 13.56 MHz and is tailored by adjusting the identical phases of the even harmonics, θ. The simulations are carried out at neutral gas pressures of 3 Pa (nearly collisionless low-pressure regime) and 100 Pa (collisional high-pressure regime). Different approaches are used in the simulations to describe the secondary electron emission (SEE) at the electrodes: we adopt (i) constant ion-induced secondary electron emission coefficients (SEECs), γ, and (ii) realistic, energy-dependent SE yields for ions and fast neutrals. The mean ion energy at the electrodes, ⟨Ei⟩, can be controlled by θ at both pressures, for both approaches adopted to describe the SEE in the simulations. At a low pressure of 3 Pa, we obtain largely different dependencies of the ion flux at the electrodes, Γi, on θ, depending on the value of the γ-coefficient. For γ=0.2, Γi remains nearly constant as a function of θ, independently of the choice of N, i.e., the mean ion energy can be controlled separately from the ion flux by adjusting θ. However, for values of γ different from 0.2, the quality of the separate control of the ion properties changes significantly. At a high pressure of 100 Pa, independently of the choice of γ, for a given N≥2, the ion flux varies as a function of θ. At both pressures, the surface conditions affect the plasma parameters and the quality of the separate control of ion properties at the electrodes. Adopting realistic, energy-dependent SE yields for heavy particles in the simulations can lead to significantly different results compared to those obtained by assuming constant SEECs.

The spatial structures of plasma parameters in a radio-frequency (RF) capacitive discharge plasma with a ring-shaped hollow electrode operated in argon were measured at various oxygen gas concentrations for plasma processing by moving a cylindrical Langmuir probe. Their distinctive profiles are obtained around the ring-shaped hollow trench. The electron temperature alt;iagt;Talt;/iagt;alt;subagt;ealt;/subagt; at the hollow trench of radial position alt;iagt;ralt;/iagt; = 37.5 mm has a peak value at an Oalt;subagt;2alt;/subagt; gas concentration of 0 %, whereas at Oalt;subagt;2 alt;/subagt;gas concentrations of 5 and 10 % Te decreases everywhere except for positions close to the hollow trench. The plasma potential alt;iagt;Valt;/iagt;alt;subagt;salt;/subagt; at an Oalt;subagt;2alt;/subagt; gas concentration of 0 % is higher than that at Oalt;subagt;2 alt;/subagt;gas concentrations of 5 and 10 %. The electron density ne has a peak value at the hollow trench at all Oalt;subagt;2alt;/subagt; gas concentrations and decreases with increasing Oalt;subagt;2alt;/subagt; gas concentration. Their axial profiles indicate unique distributions around the hollow inlet at a radial position of alt;iagt;ralt;/iagt; = 37.5 mm, while at a radial position of alt;iagt;ralt;/iagt; = 0 the profiles are almost uniform. It is found that a double layer is formed from the axial profiles of the plasma potential at alt;iagt;ralt;/iagt; = 37.5 mm for all oxygen gas concentrations.

Summary Background Early treatment of acute hepatitis C virus (HCV) infection with interferon alfa is highly effective, but can be associated with frequent side-effects. We investigated the safety and efficacy of an interferon-free regimen for treatment of acute HCV infection. Methods In this prospective, open-label, multicentre, single-arm pilot study, we enrolled adults (≥18 years) with acute HCV genotype 1 monoinfection from ten centres in Germany. Patients were given ledipasvir (90 mg) plus sofosbuvir (400 mg) as a fixed-dose combination tablet once daily for 6 weeks. The primary efficacy outcome was the proportion of patients with sustained virological response (defined as undetectable HCV RNA 12 weeks after the end of treatment; other primary outcomes were safety and tolerability of ledipasvir plus sofosbuvir. The primary analysis population consisted of all patients who received at least one dose of study drug. Safety was also assessed in all patients who received at least one dose of the study drug. This trial is registered with ClinicalTrials.gov, number NCT02309918. Findings Between Nov 19, 2014, and Nov 10, 2015, we enrolled 20 patients. Median HCV RNA viral load at baseline was 4·04 log 10 IU/mL (1·71–7·20); 11 patients were infected with HCV genotype 1a and nine patients with genotype 1b. All patients achieved a sustained virological response 12 weeks after the end of treatment (20 [100%] of 20 patients). Treatment was well tolerated; there were no drug-related serious adverse events. Up to 12 weeks after treatment, 22 possible or probable drug-related adverse events were reported. There was one serious adverse event, which was judged unrelated to the study drug; one patient was admitted to hospital for surgery of a ruptured cruciate ligament. Interpretation Treatment for 6 weeks with ledipasvir plus sofosbuvir was well tolerated and highly effective in patients with acute HCV genotype 1 monoinfection. Short-duration treatment of acute hepatitis C might prevent the spread of HCV in high-risk populations. Funding Gilead Sciences, HepNet Study-House/German Liver Foundation, and German Centre for Infection Research (DZIF).

We present results from small-angle X-ray scattering and turbidity measurements on the effect of high hydrostatic pressure on the phase behavior of dense lysozyme solutions in the liquid-liquid phase separation region, and characterize the underlying intermolecular protein-protein interactions as a function of temperature and pressure under charge-screening conditions (0.5 M NaCl). A reentrant liquid-liquid phase separation region is observed at elevated pressures, which may originate in the pressure dependence of the solvent-mediated protein-protein interaction. A temperature-pressure-concentration phase diagram was constructed for highly concentrated lysozyme solutions over a wide range of temperatures, pressures and protein concentrations including the critical region of the liquid-liquid miscibility gap.

Background Shortening the duration of treatment with HCV direct-acting antivirals (DAAs) leads to substantial cost reductions. According to the label, sofosbuvir and ledipasvir can be prescribed for 8 weeks (SL8) in noncirrhotic women or men with HCV genotype 1 and low viral loads. However, real-world data about the efficacy and safety of SL8 are largely missing. Methods Interim results from an ongoing prospective, multicenter cohort of 9 treatment centers in Germany (GECCO). All patients started on treatment with HCV DAAs since January 2014 were included. This report describes safety and efficacy outcomes in 210 patients with HCV monoinfection and 35 with human immunodeficiency virus (HIV)-HCV coinfection given SL8 in a real-world setting. Results Of 1353 patients included into the GECCO cohort until December 2015, a total of 1287 had complete data sets for this analysis; 337 (26.2%) fulfilled the criteria for SL8 according to the package insert, but only 193 (57.2%) were eventually treated for 8 weeks. Another 52 patients did not fulfill the criteria but were treated for 8 weeks. SL8 was generally well tolerated. The overall sustained virologic response rate 12 weeks after the end of treatment was 93.5% (186 of 199). The on-treatment response rate was 99.4% (159 of 160) in HCV-monoinfected and 96.4% (27 of 28) in HIV-HCV-coinfected patients. Ten patients were lost to follow-up. Conclusions SL8 seems highly effective and safe in well-selected HCV-monoinfected and HIV-HCV-coinfected patients in a real-world setting.

A Computationally Assisted Spectroscopic Technique to measure secondary electron emission coefficients ($\gamma$-CAST) in capacitively-coupled radio-frequency plasmas is proposed. This non-intrusive, sensitive diagnostic is based on a combination of Phase Resolved Optical Emission Spectroscopy and particle-based kinetic simulations. In such plasmas (under most conditions in electropositive gases) the spatio-temporally resolved electron-impact excitation/ionization rate features two distinct maxima adjacent to each electrode at different times within each RF period. While one maximum is the consequence of the energy gain of electrons due to sheath expansion, the second maximum is produced by secondary electrons accelerated towards the plasma bulk by the sheath electric field at the time of maximum voltage drop across the adjacent sheath. Due to these different excitation/ionization mechanisms, the ratio of the intensities of these maxima is very sensitive to the secondary electron emission coefficient $\gamma$. This sensitvity, in turn, allows $\gamma$ to be determined by comparing experimental excitation profiles and simulation data obtained with various $\gamma$-coefficients. The diagnostic, tested here in a geometrically symmetric argon discharge, yields an effective secondary electron emission coefficient of $\gamma = 0.066 \pm 0.01$ for stainless steel electrodes.

Resistance mutations to hepatitis C virus (HCV) nonstructural protein 3 (NS3) protease inhibitors in1% of the viral quasispecies may still allow1000-fold viral load reductions upon treatment, consistent with their reported reduced replicative fitness in vitro. Recently, however, an R155K protease mutation was reported as the dominant quasispecies in a treatment-naïve individual, raising concerns about possible full drug resistance. To investigate the prevalence of dominant resistance mutations against specifically targeted antiviral therapy for HCV (STAT-C) in the population, we analyzed HCV genome sequences from 507 treatment-naïve patients infected with HCV genotype 1 from the United States, Germany, and Switzerland. Phylogenetic sequence analysis and viral load data were used to identify the possible spread of replication-competent, drug-resistant viral strains in the population and to infer the consequences of these mutations upon viral replication in vivo. Mutations described to confer resistance to the protease inhibitors Telaprevir, BILN2061, ITMN-191, SCH6 and Boceprevir; the NS5B polymerase inhibitor AG-021541; and to the NS4A antagonist ACH-806 were observed mostly as sporadic, unrelated cases, at frequencies between 0.3% and 2.8% in the population, including two patients with possible multidrug resistance. Collectively, however, 8.6% of the patients infected with genotype 1a and 1.4% of those infected with genotype 1b carried at least one dominant resistance mutation. Viral loads were high in the majority of these patients, suggesting that drug-resistant viral strains might achieve replication levels comparable to nonresistant viruses in vivo.Naturally occurring dominant STAT-C resistance mutations are common in treatment-naïve patients infected with HCV genotype 1. Their influence on treatment outcome should further be characterized to evaluate possible benefits of drug resistance testing for individual tailoring of drug combinations when treatment options are limited due to previous nonresponse to peginterferon and ribavirin.

In capacitively coupled radio frequency (CCRF) discharges at low pressures the electron heating is dominated by electron interaction with the plasma sheath. Especially the beams of the highly energetic electrons (of which the energy is much higher than the ionization threshold of the background gas), accelerated by the expanding plasma sheaths, play a major role to sustain the plasma. At very low pressures when the electron mean free path is comparable or larger than the gap size, electron beams traverse through the bulk with hardly any collision and interact with the opposing sheath. At a certain combination of the driving frequency, the gap size and the gas pressure of the discharge, electron beams can hit the opposing sheath near its collapse. In this case, most of the highly energetic electrons can overcome the sheath potential and are lost to the electrodes. Additionally multiple beams can be generated during one phase of sheath expansion. In this work we present the effect of changing the driving frequency on the plasma density and the electron dynamics in an argon ccrf discharge. The effect is investigated by means of "Particle-in-Cell/Monte Carlo Collisions" simulations. Based on an analytical power balance model, the confinement quality and the related modulation of the energy loss per electron lost at the electrode are demonstrated. In contrast to previous assumptions, the plasma density does not follow a quadratic dependence on the driving frequency. Instead, a step-like increase at a distinct frequency is observed. In this case most of the highly energetic electrons hit the opposing sheath during its collapse.

Background & Aims: Acute hepatitis C infection progresses to chronic infection in up to 80% of infected persons. Reports from Europe indicate that early treatment of acute hepatitis C infection produces sustained virologic response rates as high as 80%–98%. However, the outcome of acute hepatitis C infection in United States cohorts is not well-characterized. Methods: We describe the clinical course of 28 episodes of acute hepatitis C infection in 24 persons at our institution. Results: Of the 28 infections, 7 episodes resolved spontaneously. Of the remaining 21 episodes, 16 were treated, and 5 did not receive treatment. Of the 16 treated episodes, 4 received interferon and ribavirin, 11 received pegylated interferon and ribavirin, and 1 was treated initially with interferon monotherapy followed by pegylated interferon monotherapy. Among those episodes treated with interferon, 3 of 4 experienced sustained virologic response. Among those episodes treated with pegylated interferon, all 12 achieved SVR. In total, 15 of 16 treated patients (94%) experienced SVR. In all, 18 of the 24 patients (75%) experienced spontaneous or treatment-induced sustained virologic clearance. Conclusions: Our experience with treated and untreated acute HCV infection is comparable to that observed in Europe. Patients treated with antiviral therapy had an excellent response. Randomized trials to investigate immediate versus delayed treatment of acute hepatitis C infection are warranted. In view of these strongly positive outcomes, increased vigilance for acute hepatitis C becomes essential.

The behavior of a dual frequency capacitively coupled plasma (2f CCP) driven by 2.26 and 13.56 MHz radio frequency (rf) source is investigated using an approach that integrates a theoretical model and experimental data. The basis of the theoretical analysis is a time dependent dual frequency analytical sheath model that casts the relation between the instantaneous sheath potential and plasma parameters. The parameters used in the model are obtained by operating the 2f CCP experiment (2.26 MHz + 13.56 MHz) in argon at a working pressure of 50 mTorr. Experimentally measured plasma parameters such as the electron density, electron temperature, as well as the rf current density ratios are the inputs of the theoretical model. Subsequently, a convenient analytical solution for the output sheath potential and sheath thickness was derived. A comparison of the present numerical results is done with the results obtained in another 2f CCP experiment conducted by Semmler et al (2007 Plasma Sources Sci. Technol. 16 839). A good quantitative correspondence is obtained. The numerical solution shows the variation of sheath potential with the low and high frequency (HF) rf powers. In the low pressure plasma, the sheath potential is a qualitative measure of DC self-bias which in turn determines the ion energy. Thus, using this analytical model, the measured values of the DC self-bias as a function of low and HF rf powers are explained in detail.

The effects of electron induced secondary electron (SE) emission from SiO2 electrodes in single-frequency capacitively coupled plasmas (CCPs) are studied by particle-in-cell/Monte Carlo collisions (PIC/MCC) simulations in argon gas at 0.5 Pa for different voltage amplitudes. Unlike conventional simulations, we use a realistic model for the description of electron-surface interactions, which takes into account the elastic reflection and the inelastic backscattering of electrons, as well as the emission of electron induced SEs (δ-electrons). The emission coefficients corresponding to these elementary processes are determined as a function of the electron energy and angle of incidence, taking the properties of the surface into account. Compared to the results obtained by using a simplified model for the electron-surface interaction, widely used in PIC/MCC simulations of CCPs, which includes only elastic electron reflection at a constant probability of 0.2, strongly different electron power absorption and ionization dynamics are observed. We find that ion induced SEs (γ-electrons) emitted at one electrode and accelerated to high energies by the local sheath electric field propagate through the plasma almost collisionlessly and impinge on the opposing sheath within a few nanoseconds. Depending on the instantaneous local sheath voltage these energetic electrons are either reflected by the sheath electric field or they hit the electrode surface, where each γ-electron can generate multiple δ-electrons upon impact. These electron induced SEs are accelerated back into the plasma by the momentary sheath electric field and can again generate δ-electrons at the opposite electrode after propagating through the plasma bulk. Overall, a complex dynamics of γ- and δ-electrons is observed including multiple reflections between the boundary sheaths. At high voltages, the electron induced SE emission is found to strongly affect the plasma density and the ionization dynamics and, thus, it represents an important plasma-surface interaction that should be included in PIC/MCC simulations of CCPs under such conditions.

Inductive discharges with radio-frequency (RF) substrate bias are frequently used for various technological applications. We operate such a hybrid discharge with a phase-locked RF substrate bias at twice the frequency of the inductive coupling with fixed but adjustable phase between both RF sources in neon at low pressures of a few Pa. The ion flux to the substrate is found to be a function of this relative phase in the H-mode at constant RF powers as long as some residual capacitive coupling of the planar coil is present. For distinct choices of the phase, Phase Resolved Optical Emission Spectroscopy measurements show that energetic beam electrons generated by the expanding boundary sheaths (i) are well confined, (ii) are accelerated efficiently, and (iii) propagate vertically through the inductive skin layer at the times of maximum azimuthal induced electric field within the fundamental RF period. This enhances the inductive stochastic electron heating, the power coupling efficiency, and finally the ion...

In particle-in-cell/Monte Carlo collisions (PIC/MCC) simulations of capacitively coupled plasmas (CCPs), the plasma-surface interaction is generally described by a simple model in which a constant secondary electron emission coefficient (SEEC) is assumed for ions bombarding the electrodes. In most PIC/MCC studies of CCPs, this coefficient is set to γ = 0.1, independent of the energy of the incident particle, the electrode material, and the surface conditions. Here, the effects of implementing energy-dependent secondary electron yields for ions, fast neutrals, and taking surface conditions into account in PIC/MCC simulations is investigated. Simulations are performed using self-consistently calculated effective SEECs, , for 'clean' (e.g., heavily sputtered) and 'dirty' (e.g., oxidized) metal surfaces in single- and dual-frequency discharges in argon and the results are compared to those obtained by assuming a constant secondary electron yield of for ions. In single-frequency (13.56 MHz) discharges operated under conditions of low heavy particle energies at the electrodes, the pressure and voltage at which the transition between the α- and γ-mode electron power absorption occurs are found to strongly depend on the surface conditions. For 'dirty' surfaces, the discharge operates in α-mode for all conditions investigated due to a low effective SEEC. In classical dual-frequency (1.937 MHz + 27.12 MHz) discharges significantly increases with increasing low-frequency voltage amplitude, , for dirty surfaces. This is due to the effect of on the heavy particle energies at the electrodes, which negatively influences the quality of the separate control of ion properties at the electrodes. The new results on the separate control of ion properties in such discharges indicate significant differences compared to previous results obtained with different constant values of γ.

Two types of capacitive dual-frequency discharges, used in plasma processing applications to achieve the separate control of the ion flux, Гi, and the mean ion energy, , at the electrodes, operated in CF4, are investigated by particle-in-cell simulations: (i) In classical dual-frequency discharges, driven by significantly different frequencies (1.937 MHz + 27.12 MHz), and Гi are controlled by the voltage amplitudes of the low-frequency and high-frequeny components, ΦLF and ΦHF, respectively. (ii) In electrically asymmetric (EA) discharges, operated at a fundamental frequency and its second harmonic (13.56 MHz + 27.12 MHz), ΦLF and ΦHF control Гi, whereas the phase shift between the driving frequencies, θ, is varied to adjust . We focus on the effect of changing the control parameter for on the electron heating and ionization dynamics and on Гi. We find that in both types of dual-frequency strongly electronegative discharges, changing the control parameter results in a complex effect on the electron heating and ionization dynamics: in classical dual-frequency discharges, besides the frequency coupling affecting the sheath expansion heating, additional frequency coupling mechanisms influence the electron heating in the plasma bulk and at the collapsing sheath edge; in EA dual-frequency discharges the electron heating in the bulk results in asymmetric ionization dynamics for values of θ around 45°, i.e., in the case of a symmetric applied

The effect of changing the driving frequency on the plasma density and the electron dynamics in a capacitive radio-frequency argon plasma operated at low pressures of a few Pa is investigated by Particle in Cell/Monte Carlo Collisions simulations and analytical modeling. In contrast to previous assumptions the plasma density does not follow a quadratic dependence on the driving frequency in this non-local collisionless regime. Instead, a step-like increase at a distinct driving frequency is observed. Based on the analytical power balance model, in combination with a detailed analysis of the electron kinetics, the density jump is found to be caused by an electron heating mode transition from the classical $\alpha$-mode into a low density resonant heating mode characterized by the generation of two energetic electron beams at each electrode per sheath expansion phase. These electron beams propagate through the bulk without collisions and interact with the opposing sheath. In the low density mode, the second beam is found to hit the opposing sheath during its collapse. Consequently, a high number of energetic electrons is lost at the electrodes resulting in a poor confinement of beam electrons in contrast to the classical $\alpha$-mode observed at higher driving frequencies. Based on the analytical model this modulated confinement quality and the related modulation of the energy lost per electron lost at the electrodes is demonstrated to cause the step-like change of the plasma density. The effects of a variation of the electrode gap, the neutral gas pressure, the electron sticking and secondary electron emission coefficients of the electrodes on this step-like increase of the plasma density are analyzed based on the simulation results.