Circulating fibrocytes as a marker of liver fibrosis in chronic hepatitis C

n/

Clustering activity at Mt Etna based on volcanic tremor: A case study

AbstractThis paper deals with the classification of volcanic activity into three classes, referred to as Quite, Strombolian and Paroxysm. The main purpose is to give a measure of the reliability with which such a classification, typically carried out by experts, can be performed by Machine Learning algorithms, by using the volcanic tremor as a feature. Both supervised and unsupervised methods are considered. It is experimentally shown that at least the Paroxysm activity can be reliably classified. Performances are rigorously assessed, in comparison with the classification made by expert volcanologists, in terms of popular indices such as thef1-score and the Area under the ROC curve (AuC). The work is basically a case study carried out on a dataset recorded in the area of the Mt Etna volcano. However, as volcanic tremor is a geophysical signal widely available, considered methods and strategies can be easily applied to similar volcanic areas

Experimental investigation of a sheared thermally unstable boundary layer

In many natural and industrial systems, heat is transported by mixed convection, where an externally driven flow causes advection of the temperature field in addition to the fluid motion due to buoyancy of differentially heated areas. We investigate experimentally the heat flux across a thermally unstable boundary layer subject to a shear flow. In the experiment, we use a two meter long aluminium plate that is subject to a shear flow above its heated surface. For varying Richardson, Reynolds and Grashof numbers, we measure the heat flux from the plate, as well as the vertical velocity and temperature profiles above it by using hot-wire anemometry and thermistors arrays. The fluid is air at atmospheric pressure, resulting in a Prandtl number of Pr = 0.75. The goal of this research is not only to investigate the transition from fully forced to dominantly free convection, but we also hope to better understand the difference between a shear driven turbulent boundary layer and a laminar boundary layer which is perturbed by thermal plumes.2021-07-0

A case study of eruptive fissure opening at Mount Etna

AbstractThis paper deals with the online offset detection in GPS time series recorded in volcanic areas. The interest for this problem lies in the fact that an offset can indicate the opening of eruptive fissures. A Change Point Detection algorithm is applied to carry out, in an online framework, the offset detection. Experimental results show that the algorithm is able to recognize the offset generated by the Mount Etna eruption, occurred on December 24, 2018, with a delay of about 4 samples, corresponding to 40 min, compared to the best offline detection. Furthermore, analysis of the trade-off between success and false alarms is carried out and discussed

Changes in serum Interleukin-33 concentration before and after treatment with pegylated interferon alfa-2a plus ribavirin in patients with chronic hepatitis C genotype 1b infection.

BACKGROUND: IL-33 is a novel member of the IL-1 family, which has been shown to play an important role in T helper 2 (Th2)-associated immune responses. Recent studies have suggested a possible role for IL-33 in the pathogenesis of liver damage during acute and chronic hepatitis; furthermore, IL-33 may be involved in the development and progression of liver fibrosis. OBJECTIVES: To evaluate serum IL-33 levels in a group of patients with chronic hepatitis C (CHC) genotype 1b at enrolment and after a course of pegylated (PEG)-IFN plus ribavirin. PATIENTS AND METHODS: 60 patients with chronic hepatitis C (CHC) and 65 healthy controls were examined and compared for serum IL-33 levels by ELISA. All CHC patients were submitted to liver biopsy either before starting antiviral treatment or during post-treatment follow up. We evaluated whether post-treatment IL-33 concentration was associated with histologic outcome as well as with virologic response to therapy. RESULTS: Serum IL-33 levels were significantly higher among CHC patients in comparison with healthy controls. IL-33 concentration was lower among patients with a METAVIR fibrosis score F1-F2, compared with those having a more advanced liver disease (METAVIR stage F3-F4). In addition, sustained virologic response (SVR) was associated with a significant drop in IL-33 levels, whereas no changes were found among relapsers and nonresponders. Analogously, patients experiencing liver histologic improvement after antiviral therapy had lower post-treatment IL-33 levels in comparison with baseline values. Contrarily, no variations were detected among subjects with worsened or stable histologic features. CONCLUSIONS: IL-33 may represent a new and easy-to-detect biomarker for the diagnosis of liver damage in CHC patients, as it appears to be modulated in parallel with biochemical and histologic parameters, such as ALT levels and liver fibrosis. Furthermore, considering that serum IL-33 concentration was significantly reduced following a successful course of antiviral treatment, this cytokine may also represent a sensitive indicator of SVR

Denoising gravity and geomagnetic signals from Etna volcano (Italy) using multivariate methods

Abstract. Multivariate methods were applied to denoise the gravity and geomagnetic signals continuously recorded by the permanent monitoring networks on the Etna volcano. Gravity and geomagnetic signals observed in volcanic areas are severely influenced by meteorological variables (i.e. pressure, temperature and humidity), whose disturbances can make the detection of volcanic source effects more difficult. For volcano monitoring it is necessary, therefore, to reduce the effects of these perturbations. To date filtering noise is a very complex problem since the spectrum of each noise component has wide intervals of superposition and, some times, traditional filtering techniques provide unsatisfactory results. We propose the application of two different approaches, the adaptive neuro-fuzzy inference system (ANFIS) and the Independent Component Analysis (ICA) to remove noise effects from gravity and geomagnetic time series. Results suggest a good efficiency of the two proposed approaches since they are capable of finding and effectively representing the underlying factors or sources, and allow local features of the signal to be detected

HIV RNA Suppression and Immune Restoration: Can We Do Better?

HAART has significantly changed the natural history of HIV infection: patients receiving antiretrovirals are usually able to control viremia, even though not all virological responders adequately recover their CD4+ count. The reasons for poor immune restoration are only partially known and they include genetic, demographic and immunologic factors. A crucial element affecting immune recovery is immune activation, related to residual viremia; indeed, a suboptimal virological control (i.e., low levels of plasma HIV RNA) has been related with higher levels of chronic inflammation and all-cause mortality. The sources of residual viremia are not yet completely known, even though the most important one is represented by latently infected cells. Several methods, including 2-LTR HIV DNA and unspliced HIV RNA measurement, have been developed to estimate residual viremia and predict the outcome of antiretroviral therapy. Considering that poor immunologic responders are exposed to a higher risk of both AIDS-related and non-AIDS-related diseases, there is a need of new therapeutic strategies, including immunomodulators and drugs targeting the latent viral reservoirs, in order to face residual viremia but also to “drive” the host immunologic responses

Microbial translocation in chronic liver diseases.

The intestinal microflora is not only involved in the digestion of nutrients, but also in local immunity, forming a barrier against pathogenic microorganisms. The derangement of the gut microflora may lead to microbial translocation, defined as the passage of viable microorganisms or bacterial products (i.e., LPS, lipopeptides) from the intestinal lumen to the mesenteric lymph nodes and other extraintestinal sites. The most recent evidence suggests that microbial translocation (MT) may occur not only in cirrhosis, but also in the early stage of several liver diseases, including alcoholic hepatopathy and nonalcoholic fatty liver disease. Different mechanisms, such as small intestinal bacterial overgrowth, increased permeability of intestinal mucosa, and impaired immunity, may favor MT. Furthermore, MT has been implicated in the pathogenesis of the complications of cirrhosis, which are a significant cause of morbidity and mortality in cirrhotic subjects. Therapeutic strategies aiming at modulating the gut microflora and reducing MT have focused on antibiotic-based options, such as selective intestinal decontamination, and nonantibiotic-based options, such as prokinetics and probiotics. In particular, probiotics may represent an attractive strategy, even though the promising results of experimental models and limited clinical studies need to be confirmed in larger randomized trials

Incidence of Mediterranean Spotted Fever in Sicilian children: a clinical-epidemiological observational retrospective study from 1987 to 2010

Background: Zoonoses are human infectious diseases caused by pathogens that primarily infect animals. Mediterranean Spotted Fever (MSF) represents one such example, affecting the Mediterranean region, in which household animals can be immune-carriers of infected ticks. Materials and methods: We retrospectively analysed the incidence and the clinical and laboratory features of MSF caused by R.Conorii in children admitted to the Paediatric Operative Unit from 1987 to 2010, for persistent fever and generalised macular-popular erythematous lesions. Clinical, immunological and serological parameters of 55 cases of Rickettsia infections observed in children between 2 and 11 years of age were collected. Results: We found an increasing incidence of MSF in childhood from 1987 to 2010. Diagnosis of MSF at the moment of hospital admission was done in 16 patients (29.09%). The presence of the typical Tache noire was observed in 16 cases out of 55 patients (29.09% of cases). We noticed a different representation of R. conorii antigens in serological testing over the time period of the study, corresponding to overall higher incidence rates for infection in the latter years. We also observed a higher incidence of infection in those years in which all four antigens were found positive at serum testing with respect to those years in which only two of the four antigens were observed (1987-1990: 0-16%; 2007-2010: 0.46%; P<0.005). Conclusions: These changes in R. conorii antigenicity may be the cause of higher pathogenicity in this parasite, perhaps linked to increased immigration along with consequent changes in the epidemiology of infectious diseases in host countries

Acute Glomerulonephritis in a Child with Chlamydia pneumoniae Infection: A Case Report.

Background. Infectious diseases seem to be an important and independent risk factor for renal failure, but the underlying mechanism of renal involvement during some kinds of infectious diseases is still unclear, even if the literature data report immunomediated and/or autoimmune mechanisms to explain the pathogenic relationship between the two diseases. In paediatric patients, Chlamydia pneumoniae is a rare cause of renal complications and it may manifest in several ways, mainly involving the respiratory system, even if also renal and glomerulalr complications, have been described. Case Diagnosis/Treatment. Herein we report a case of a 3-year-old child who developed an acute glomerulonephritis that was chronologically, clinically, and biologically related to a previous Chlamydia pneumoniae infection. On our knowledge, in the literature it is the youngest patient with renal involvement during course of Chlamydia pneumoniae infection ever reported. Conclusions. The present case supports the hypothesis of a rather close causal relationship between this infective agent and renal and glomerular symptoms occurred in this child, during an acute episode of respiratory disease