914 research outputs found

    HCV-1b intra-subtype variability: Impact on genetic barrier to protease inhibitors

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    Due to error-prone RNA polymerase and the lack of proofreading mechanisms, to the spread worldwide and probable long-term presence in human population, HCV showed a high degree of inter- and intra-subtype genetic variability. Protease inhibitors (PIs), a new class of drugs, have been designed specifically on the HCV genotype 1 NS3 protease three-dimensional structure. The viral genetic barrier limits the efficacy of PIs, and fourteen loci in the HCV NS3 gene are involved in resistance to PIs. A sensitive method (15UI/ml) for study the HCV genetic profile of 125 strains from patients naïve to PIs, was developed through the use of new degenerate primers for subtype 1b. We observed the presence of naturally resistance-associated variants in 14% of the HCV strains (V36L, F43S, T54S, I153V, R155Q, D168A/G). T54S was the most common mutation (4%) detected. We investigated, through minimal score (m.s.) calculating, how the HCV intra-subtype 1b variability modifies the genetic barrier to PIs. For >60% of strains a single transition (m.s. of 1) was required for selection of low to medium resistance mutations, while more than one transition/transversion (m.s. ⩾2.5) or one transition plus one transversion (m.s. ⩾3.5) was necessary for most of the high level PI-resistant-associated mutations, except for A156V, for which a single transition was sufficient (m.s. of 1). However, the presence at locus 36 of the amino acid polymorphism S36 in one case and the wild type V36 in 6 isolates, encoded by unusual GTA or GTG codons, might determined a higher probability of V36L/M mutations because of the reduction of the genetic barrier. Instead, the presence of the CGA and CGT codons in the 155(th) position increases the genetic barrier for R155M or R155Q/M. The large intra-subtype variability, suggests that a routine baseline resistance test must be used before PIs-treatment

    Phylogenetic Analysis of isolates from new cases of HBV infection in Southern Italy.

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    The level of endemicity of hepatitis B virus (HBV) infections in Italy is low and genotype D infections predominant. New HBV strains may however be introduced as a result of movements of people from regions of high endemicity. The aim of the present study was to determine whether strains from new cases of acute hepatitis B detected in southern Italy were due to endemic or new HBV strains. We studied 34 isolates from patients with acute hepatitis B infection, and 35 from chronic hepatitis B patients. A phylogenetic analysis of preS/S region was done by comparing the sequences from the acute and chronic cases with references sequences. The study showed that 44% of strain from acute hepatitis B patients were of genotype A, 53% of genotype D, and 3% of genotype E. The molecular analysis of isolates from acute hepatitis B patients from Sicily showed a change in the local epidemiology of this infection, with an increase in HBV/A infections and a clustering effect for HBV D2, possibly correlated to immigration. The introduction of new genotypes , could have an effect on HBV-correlated diseases due to the different association between genotype, liver disease and response to antiviral therapy

    LOWER LIMB REVASCULARIZATION WITH A NEW BIOACTIVE PROSTHETIC GRAFT: EARLY AND LATE RESULTS

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    Subsurface structure of the Solfatara volcano (Campi Flegreicaldera, Italy) as deduced from joint seismic-noise array,volcanological and morphostructural analysis

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    The joint application of different seismological techniques for seismic noise analysis, and the results of a volcanological and morphostructural survey, have allowed us to obtain a detailed and well constrained image of the shallow crustal structure of the Solfatara volcano (Campi Flegrei caldera, Italy). Horizontal-to-vertical spectral ratios, inversion of surface wave dispersion curves and polarization analysis provided resonance frequencies and peak amplitudes, shear wave velocity profiles and polarization pattern of coherent ambient noise. These results, combined in a unique framework, indicate that the volcanic edifice is characterized by lateral and vertical discontinuities and heterogeneities in terms of shear wave velocity, lithological contrasts and structural setting. The interpretation of the seismological results, with the volcanological and morphostructural constraints, supports the hypothesis that the volcano has been characterized by a complex and intense activity, with the alternation of constructive and destructive phases, during which magmatic and phreatomagmatic explosions built a complex tuff-cone, later reworked by atmospheric agents and altered by hydrothermal activity. The differences in the velocity structure between the central and eastern parts of the crater have been interpreted as resulting from a possible eastward migration of the eruptive vent along the deformational features affecting the area, and to the presence of viscous lava and lithified tuff bodies within the feeding conduits, which are buried under a covering of reworked materials of variable thickness. The observed fault and fracture systems, partially inherited from regional structural setting and exhumed during volcanism and ground deformation episodes also seems to strongly control wave propagation, affecting the noise polarization properties

    Liver eosinophilic infiltrate is a significant finding in patients with chronic hepatitis C.

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    Eosinophilic infiltrate of liver tissue is described in primary cholestatic diseases, hepatic allograft rejection and drug-induced liver injury, but its significance and its implications in chronic hepatitis C are unknown. The aim of this study was to investigate the clinical significance of eosinophilic liver infiltrate in patients with chronic hepatitis C. We retrospectively evaluated 147 patients with chronic hepatitis C. The presence of eosinophilic infiltrate was investigated in liver biopsies, and a numeric count of eosinophilic leucocytes in every portal tract was assessed. An eosinophilic infiltrate of liver tissue (≥3 cells evaluated in the portal/periportal spaces) was observed in 46 patients (31%), and patients who consumed drugs had an odds ratio (OR) of 4.02 (95% CI: 1.62-9.96) to have an eosinophilic infiltrate in liver biopsy. By logistic regression analysis, the presence of steatosis was independently associated with eosinophilic infiltrate (OR 5.86; 95% CI: 2.46-13.96) and homeostasis model assessment-score (OR 1.18; 95% CI: 1.00-1.39). Logistic regression analysis also showed that fibrosis staging ≥ 2 by Scheuer score was associated with grading >1 by Scheuer score (OR 6.82; 95% CI 2.46-18.80) and eosinophilic infiltrate (OR 4.00; 95% CI 1.23-12.91). In conclusion, we observed that the eosinophilic infiltrate of liver tissue was significantly more frequent in patients who assumed drugs, and found a significant association between eosinophilic infiltrate, liver steatosis and liver fibrosis. These preliminary data could lead to a constant assumption of drugs as a co-factor of eosinophils-mediated liver injury in chronic hepatitis

    Candidemia after cardiac surgery in the intensive care unit: an observational study

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    Candidemia is a well-recognized complication of hospital stay, especially in critically ill patients. There is not a general consensus that predictors for candidemia in cardiosurgical intensive care unit (cICU) are different from a general ICU and it has been reported that cardiopulmonary bypass time is a specific risk factor in the cICU. We performed a prospective study to evaluate the main predictors for candidemia in patients admitted to the cICU. Included patients were adults admitted between July 2005 and December 2007 with an ICU-length of stay (ICU-LOS) ≥48 hours after cardiac surgery. Exclusion criteria were solid organ or bone marrow transplants, previous diagnosis of candidemia or other invasive infections and ICU stay before surgery. A multiple regression analysis was performed to identify the risk factors. Among 1955 patients admitted to the cICU, 345 were enrolled. Only 26 patients (1.3%) had candidemia after an ICU-LOS of 20 days (inter-quartile range, IQR 8-49 days). Total parenteral nutrition [odds ratio (OR) = 9.56; confidence interval (CI) = 1.741-52.534], severe sepsis (OR = 4.20; CI = 1.292-13.667), simplified acute physiology score II (OR = 1.16; CI = 1.052-1.278) and ICU-LOS >20 days (OR=6.38; CI = 1.971-20.660) were independent predictors of candidemia. Patients undergoing cardiac surgery developed candidemia late after cICU admission and the independent predictors were similar to the general ICU. © 2011 Published by European Association for Cardio-Thoracic Surgery

    Screening techniques and sources of resistance to nematodes in cool season food legumes

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    Identification of sources of resistance in cool season legumes to cyst (Heterodera spp.), root-knot (Meloidogyne spp.), and stem nematode (Ditylenchus dipsaci) is generally based on number of cysts on roots, root-knot nematode induced gall index, and stem nematode reproduction in shoot tissue, respectively . Various levels of resistance to cyst nematodes have been detected in chickpea and pea. Resistance has also been identified in chickpea, faba bean, and pea to the root-knot nematodes . Broad based durable sources of resistance to plant parasitic nematodes are required . Basic research is needed to develop transgenic plants with resistance based on hatch stimulants, inhibitors, toxins, or repellents found in antagonistic rhizosphere microorganisms . Selection of genotypes that favor development of beneficial rhizosphere microorganisms or root endophytes that increase the plant resistance to nematode infection deserves attentio

    Aurora Kinase A expression predicts platinum-resistance and adverse outcome in high-grade serous ovarian carcinoma patients

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    High-Grade Serous Ovarian Carcinoma (HGSOC) is the predominant histotype of epithelial ovarian cancer (EOC), characterized by advanced stage at diagnosis, frequent TP53 mutation, rapid progression, and high responsiveness to platinum-based-chemotherapy. To date, standard first-line-chemotherapy in advanced EOC includes platinum salts and paclitaxel with or without bevacizumab. The major prognostic factor is the response duration from the end of the platinum-based treatment (platinum-free interval) and about 10-0 % of EOC patients bear a platinum-refractory disease or develop early resistance (platinum-free interval shorter than 6 months). On these bases, a careful selection of patients who could benefit from chemotherapy is recommended to avoid unnecessary side effects and for a better disease outcome. In this retrospective study, an immunohistochemical evaluation of Aurora Kinase A (AURKA) was performed on 41 cases of HGSOC according to platinum-status. Taking into account the number and intensity of AURKA positive cells we built a predictive score able to discriminate with high accuracy platinum-sensitive patients from platinum-resistant patients (p < 0.001). Furthermore, we observed that AURKA overexpression correlates to worse overall survival (p = 0.001; HR 0.14). We here suggest AURKA as new effective tool to predict the biological behavior of HGSOC. Particularly, our results indicate that AURKA has a role both as predictor of platinum-resistance and as prognostic factor, that deserves further investigation in prospective clinical trials. Indeed, in the era of personalized medicine, AURKA could assist the clinicians in selecting the best treatment and represent, at the same time, a promising new therapeutic target in EOC treatment
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