Behavior of different soot combustion catalysts under NOx/O2. Importance of the catalyst–soot contact

Four different catalysts (Pt/Al2O3, Ce0.8Zr0.2O2, PrO2−x and SrTiCuO3) have been investigated on a laboratory scale to evaluate their potential as diesel soot combustion catalysts under different experimental conditions, which simulate the situation found in a continuous regeneration technology trap (dual-bed configuration of catalyst and soot) or a catalyst-coated filter system (single-bed configuration, both catalyst and soot particles mixed under loose-contact mode). Under dual-bed configuration, the behavior of the catalysts towards soot combustion are very similar, despite the differences observed in the NO2 production profiles. However, under single-bed configuration, there are important differences in the soot combustion activities and in the NO2 slip profiles. The configurations chosen have an enormous impact on CO/(CO + CO2) ratios of combustion products as well. The most active catalyst under NOx + O2 is PrO2−x combining a high contribution of active oxygen-assisted soot combustion as well as high NO2 production activity along the catalytic bed.Financial support of Generalitat Valenciana (Prometeo/2009/047 project) and the Spanish Ministry of Science and Innovation (project CTQ2012-30703, which is co-funded by FEDER resources). N. G. H. wishes to thank Generalitat Valenciana her Ph.D. grant within VAL i+d Program

GEHEP 010 study: Prevalence and distribution of hepatitis B virus genotypes in Spain (2000–2016)

[Objective] To study the prevalence and distribution of HBV genotypes in Spain for the period 2000–2016.[Methods] Retrospective study recruiting 2559 patients from 17 hospitals. Distribution of HBV genotypes, as well as sex, age, geographical origin, mode of transmission, HDV-, HIV- and/or HCV-coinfection, and treatment were recorded.[Results] 1924 chronically HBV native Spanish patients have been recruited. Median age was 54 years (IQR: 41–62), 69.6% male, 6.3% HIV-coinfected, 3.1% were HCV-coinfected, 1.7% HDV-co/superinfected. Genotype distribution was: 55.9% D, 33.5% A, 5.6% F, 0.8% G, and 1.9% other genotypes (E, B, H and C). HBV genotype A was closely associated with male sex, sexual transmission, and HIV-coinfection. In contrast, HBV genotype D was associated with female sex and vertical transmission. Different patterns of genotype distribution and diversity were found between different geographical regions. In addition, HBV epidemiological patterns are evolving in Spain, mainly because of immigration. Finally, similar overall rates of treatment success across all HBV genotypes were found.[Conclusions] We present here the most recent data on molecular epidemiology of HBV in Spain (GEHEP010 Study). This study confirms that the HBV genotype distribution in Spain varies based on age, sex, origin, HIV-coinfection, geographical regions and epidemiological groups.This study has been funded in part by the funds of the research project GEHEP-2018-010, granted by the Hepatitis Group of the Spanish Society of Infectious Diseases and Clinical Microbiology (Grupo de Hepatitis de la Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica, GEHEP/SEIMC)

Relation of IL28B Gene Polymorphism with Biochemical and Histological Features in Hepatitis C Virus-Induced Liver Disease

BACKGROUND/AIMS: Polymorphism at the IL28B gene may modify the course of hepatitis C virus (HCV) chronic infection. Our aim was to study the influence of IL28B rs12979860 gene polymorphism on the biochemistry and pathology of HCV-induced disease in the clinical course from mild chronic hepatitis C to hepatocellular carcinoma. METHODS: We have determined the rs12979860 single nucleotide polymorphism (SNP) upstream IL28B gene in two groups of patients with HCV-induced chronic liver disease: 1) 268 patients (159 men) with biopsy-proven chronic hepatitis C, to analyse its relation with biochemical, virological and histological features; and 2) 134 patients (97 men) with HCV-related hepatocellular carcinoma. The distribution of the analysed SNP in hepatocellular carcinoma patients was compared with that found in untreated chronic hepatitis C patients. All patients were white and most were Spaniards. RESULTS: In multivariate analysis ALT values were higher (P = 0.001) and GGT values were lower (P<0.001) in chronic hepatitis C patients homozygotes for the major rs12979860C allele as compared with carriers of the mutated rs12979860T allele. Steatosis was more frequent (Odds ratio = 1.764, 95% C.I. 1.053-2.955) and severe (P = 0.026) in carriers of the rs12979860T allele. No relation was found between the analysed SNP and METAVIR scores for necroinflammation and fibrosis, and there were no differences in the distribution of the analysed SNP between hepatocellular carcinoma and untreated chronic hepatitis C patients. CONCLUSION: The IL28B rs12979860 polymorphism correlates with the biochemical activity and the presence and severity of liver steatosis in chronic hepatitis C

Preparation, characterisation and testing of CuO/Ce0.8Zr0.2O2 catalysts for NO oxidation to NO2 and mild temperature diesel soot combustion

CuO/ceria-zirconia catalysts have been prepared, deeply characterised (N2 adsorption–desorption isotherms at −196 °C, XRD, Raman spectroscopy, XPS, TEM and H2-TPR) and tested for NO oxidation to NO2 in TPR conditions, and for soot combustion at mild temperature (400 °C) in a NOx/O2 stream. The behaviour has been compared to that of a reference Pt/alumina commercial catalyst. The ceria-zirconia support was prepared by the co-precipitation method, and different amounts of copper (0.5, 1, 2, 4 and 6 wt%) were loaded by incipient wetness impregnation. The results revealed that copper is well-dispersed onto the ceria-zirconia support for the catalysts with low copper loading and CuO particles were only identified by XRD in samples with 4 and 6% of copper. A very low loading of copper increases significantly the activity for the NO oxidation to NO2 with regard to the ceria-zirconia support and an optimum was found for a 4% CuO/ceria-zirconia composition, showing a very high activity (54% at 348 °C). The soot combustion rate at 400 °C obtained with the 2% CuO/ceria-zirconia catalyst is slightly lower to that of 1% Pt/alumina in terms of mass of catalyst but higher in terms of price of catalyst.Financial support of Generalitat Valenciana (Prometeo/2009/047 project), the Spanish Ministry of Economy and Competitiveness (CTQ2012-30703project) and the UE (FEDER funding)

Influence of vitamin D-related gene polymorphisms (CYP27B and VDR) on the response to interferon/ribavirin therapy in chronic hepatitis C.

Vitamin D exerts immunomodulatory effects on the host response against infection with hepatitis C virus (HCV). This study was performed to assess the putative influence of polymorphisms in vitamin D-related genes on the response to antiviral therapy in patients with chronic hepatitis C (CHC).Single nucleotide polymorphisms (SNPs) in CYP27B-1260 gene promoter (rs10877012AC) and in vitamin D receptor (VDR) gene rs2228570TC, rs1544410CT, rs7975232AC and rs731236AT were analyzed in a cohort of 238 Caucasian CHC patients treated with pegylated interferon (Peg-IFN) plus ribavirin (RBV). Multivariate analyses were performed to exclude confounding effects of well-known baseline predictors of response to therapy (HCV genotype and load, IL28B genotype, age, and GGT and serum cholesterol).Three SNPs at the VDR gene (rs1544410, rs7975232 and rs731236) were in strong linkage disequilibrium, with the CCA haplotype predicting therapeutic failure [Odds ratio 2.743; (95% C.I. 1.313-5.731), p = 0.007]. The carrier state of the VDR rs2228570 T allele was inversely related to the probability of therapeutic failure [Odds ratio 0.438; 95 C.I. (0.204-0.882), p = 0.021]. No relation existed between CYP27B-1260 rs10877012 polymorphism and response to therapy. The area under the operating curve (AUROC) based on the model including all variables significantly related to the response to therapy was 0.846 (95% confidence interval = 0.793-0.899).VDR gene polymorphisms are independently related to the response to Peg-IFN+RBV therapy in chronic hepatitis C and could be used as complementary biomarkers of response when included in a prediction algorithm in association with demographic, virologic, biochemical and genetic traits

Vitamin D deficiency and vitamin D therapy in chronic hepatitis C

Background. Vitamin D has immunomodulatory properties, exerts an anti-hepatitis C virus (HCV) effect in vitro and improves response to interferon-based therapy in patients with chronic hepatitis C (CHC). Low serum levels of 25(OH) vitamin D [25(OH)D] are frequently found in CHC patients and seem to be related to more advanced stages of liver fibrosis. The study aims to establish the incidence of vitamin D deficiency in Spanish patients with CHC, its possible relation with features of liver damage and with the IL28B gene polymorphism, and the immediate effect of vitamin D therapy on CHC-related analytical variables.Materials and methods. Baseline serum 25(OH)D levels were measured in 108 consecutive CHC patients (60 men, age 54.3 ± 10.5 yrs). Results of transient elastography and of IL28B rs12979860C/T genotype were available in 89 and 95 patients, respectively. Forty one patients with insufficient levels of 25(OH)D received vitamin D supplements and were re-evaluated thereafter.Results. Deficiency of vitamin D (< 20 µg/dL) and suboptimal levels (20–30 µg/mL) were detected in 36.1% and 40.9% of patients, respectively. No relationships were found between 25(OH)D levels and biochemical liver tests, fibrosis stage and IL28B genotype. Vitamin D therapy normalized 25(OH)D levels in all treated patients, but did not modify significantly HCV-RNA serum levels or biochemical tests.Conclusions. Vitamin D deficiency is common in Spanish patients with CHC but it is related neither to biochemical and virological variables nor with the fibrosis stage and IL28B polymorphism. Vitamin D therapy has no immediate effect on HCV-RNA serum levels

The relation of fibrosis stage with nutritional deficiencies and bioelectrical impedance analysis of body composition in patients with chronic hepatitis C

Background. Nutritional deficiencies may aggravate the course of chronic hepatitis C (CHC). Our aim has been to perform a comprehensive analysis of body composition and nutritional deficiencies in CHC patients in non-cirrhotic and compensated cirrhotic stages to correlate the detected deficiencies with the fibrosis stage.Material and methods. Body multifrequency bioimpedance analysis (BIA) and a wide and simultaneous analytical profile were prospectively performed in 74 CHC patients (36 male) with known METAVIR fibrosis stage established with liver biopsy or transient elastography. Results were analyzed to identify deviations from the normal range and variations according to the fibrosis stage.Results. Body fat compartment was greater in women. Body composition did not change among the 4 stages of liver fibrosis. Low levels (< 30 μg/L) of vitamin D were detected in 74.3% of patients irrespective of the fibrosis stage. Most analytical results remained into the normal range with the exceptions of thrombocytopenia and vitamin A deficiency, that were limited to the stage 4 of fibrosis, and low Zn and LDL-cholesterol values, that were frequently found in patients with advanced (F3 and F4) fibrosis stage.Conclusion. Body composition and most biochemical parameters, including cyanocobalamin, folic acid and vitamin E, are well preserved in compensated patients with CHC, with the exception of generalized vitamin D insufficiency and of deficiencies of vitamin A and zinc that are restricted to the more advanced, although still compensated, stages of the disease

Logistic regression analysis of demographic, biochemical and virological variables at baseline and of <i>CYP27B1, VDR</i> and <i>IL28B</i> gene polymorphisms in relation with the lack of response (failure to antiviral therapy) in 238 patients with chronic hepatitis C.

(1)<p>Continuous variables are given as mean (SD).</p>(2)<p>Odds ratio (95% confidence interval).</p>(3)<p>Odds ratio (95% confidence interval) and <i>p value</i> in all significant variables in the univariate analysis. <i>CYP27B1</i>and <i>VDR</i> gene polymorphisms were forced into the analysis.</p