A Geomechanical Approach to Landslide Hazard Assessment: The Multiscalar Method for Landslide Mitigation

AbstractThe landslide hazard assessment, when based on the deterministic diagnosis of the processes, can be pursued only through the interpretation and the geo-hydro-mechanical modelling of the slope equilibrium. In practice, though, landslide hazard assessment is still seldom dealt with slope modelling, in particular when it addresses vast areas, where either heuristic or statistical methods do not entail any geo-hydro-mechanical knowledge of slope features and stability. The Multiscalar Method for Landslide Mitigation (MMLM) is an original methodological approach for intermediate to regional landslide hazard assessment. It is based on the geo-hydro-mechanical knowledge achieved from the application of a stage-wise diagnostic methodology of the landslide mechanism at the slope scale. The paper discusses the main steps of the MMLM aiming at diagnoses of landslide hazard based on hydro-mechanics, for small scale hazard mapping (at the large area)

Different patterns of HIV-1 DNA after therapy discontinuation

Background: By persisting in infected cells for a long period of time, proviral HIV-1 DNA can represent an alternative viral marker to RNA viral load during the follow-up of HIV-1 infected individuals. In the present study sequential blood samples of 10 patients under antiretroviral treatment from 1997 with two NRTIs, who refused to continue any antiviral regimen, were analyzed for 16-24 weeks to study the possible relationship between DNA and RNA viral load. Methods: The amount of proviral DNA was quantified by SYBR green real-time PCR in peripheral blood mononuclear cells from a selected group of ten patients with different levels of plasmatic viremia (RNA viral load). Results: Variable levels of proviral DNA were found without any significant correlation between proviral load and plasma HIV-1 RNA levels. Results obtained showed an increase or a rebound in viral DNA in most patients, suggesting that the absence of therapy reflects an increase and/or a persistence of cells containing viral DNA. Conclusion: Even though plasma HIV RNA levels remain the basic parameter to monitor the intensity of viral replication, the results obtained seem to indicate that DNA levels could represent an adjunct prognostic marker in monitoring HIV-1 infected subjects

Serum antibody reactivity to human intracisternal A-type particle retrovirus proteins in systemic sclerosis patients.

Serum antibodies against human intracisternal A-typeparticle (HIAP) endogenous retrovirus have been foundto be associated with various autoimmune pathologies.To evaluate the presence of serum antibody reactivityto HIAP proteins in systemic sclerosis, a Western blotanalysis was performed on sera from 42 patients withsystemic sclerosis, in comparison with 18 sera frompatients with primary biliary cirrhosis and 52 healthysubjects. A positive Western blot was found in 55.5% ofserum samples from patients with primary biliarycirrhosis and in 66.0% of patients with systemic sclerosis.None of the 52 healthy subjects showed positive results.Although this difference may be attributable either to anautoimmune response to antigenically related cellularproteins or to a specific antibody response to HIAPproteins expressed as an incidental consequence ofattendant pathological processes, the high prevalence ofantibodies against HIAP proteins demonstrated inpatients with systemic sclerosis may be considered ahallmark of this disease.(Accepted November 10, 2003.)Acta Derm Venereol 2004; 84: 177–180.Dr Michelangelo La Placa, Department of Clinicaland Experimental Medicine, Section of Dermatology,Via Massarenti, 1, 40138 Bologna, Italy. E-mail:[email protected] sclerosis (SSc) is a connective tissue diseasecharacterized by excessive deposition of collagen inthe skin and various internal organs, and by vascularabnormalities (1). SSc is considered to be an auto-immune disease. Although both cellular microchimer-ism (2) and molecular mimicry of some commoninfectious agents, such as cytomegalovirus and parvo-virus B19 (3), have been implicated in its pathogenesis,the aetiology of SSc remains unknown.Several publications have described the presence ofretroviral sequences associated with virions, producedby cells of patients with autoimmune diseases. In recentreviews (4, 5), these viruses, identified as human endo-genous retroviruses (HERVs), have been associatedwith Sjo¨grens's syndrome, type 1 or insulin-dependentdiabetes mellitus, multiple sclerosis, rheumatoid arthri-tis, congenital heart block, systemic lupus erythemato-sus and SSc. Serum antibodies specific for humanintracisternal A-type particles (HIAP), a HERV recog-nized by monoclonal antibody against HIV-1 p24capsid protein (6), have been found in primary biliarycirrhosis (PBC) (7), familial erosive arthritis (8) andsome patients with SSc, systemic lupus erythematosus,Still's disease and idiopathic T-lymphocytopenia (9,10).To further investigate serum antibody reactivity toHIAP proteins in SSc, we performed a Western blotanalysis of a substantial number of sera from SScpatients, in comparison with sera from PBC patientsand healthy subjects.MATERIALS AND METHOD

Analysis of HIV-1 drug resistant mutations by line probe assay and direct sequencing in a cohort of therapy naive HIV-1 infected Italian patients

BACKGROUND: The routine determination of drug resistance in newly HIV-1 infected individuals documents a potential increase in the transmission of drug-resistant variants. Plasma samples from twenty seven therapy naive HIV-1 infected Italian patients were analyzed by the line probe assay (LIPA) and the TruGene HIV-1 assay for the detection of mutations conferring resistance to HIV-1. RESULTS: Both tests disclosed amino-acid substitutions associated with resistance in a variable number of patients. In particular, two mutations (K70R and V118I), detectable by LIPA and by sequencing analysis respectively, revealed resistance to NRTIs in two plasma samples. At least three mutations conferring resistance to NNRTIs, not detectable by commercial LIPA, able to reveal mutations associated only with nucleoside reverse transcriptase analogues, were disclosed by viral sequence analysis. Moreover, most samples showed mutations correlated with resistance to protease inhibitors. Remarkably, a key mutation, like V82A (found as a mixture), and some "indeterminate" results (9 samples), due the absence of signal on the lines corresponding to a specific probe, was revealed only by LIPA, while a variable number of secondary mutations was detectable only by TruGene HIV-1 assay. CONCLUSION: Even if further studies are necessary to establish the impact of different tests on the evaluation of drug-resistant strains transmission, LIPA might be useful in a wide population analysis, where bulk results are needed in a short time, while sequencing analysis, able to detect mutations conferring resistance to both NRTIs and NNRTIs, might be considered a more complete assay, albeit more expensive and more technically complex

Sustainable environmental geotechnics practices for a green economy

The revitalisation of the global economy after the Covid-19 era presents environmental geotechnics with the opportunity to reinforce the need for a change in paradigm towards a green, circular economy and to promote aggressively the use and development of sustainable technologies and management practices. This paper aims to assist in this effort by concentrating on several thematic areas where sustainability solutions and future improvements are sought. These include the re-entry of construction and demolition of wastes, excavated materials, industrial wastes and marine sediments into the production cycle and the reuse of existing foundations. Despite the recent trend in advanced countries towards recycling and waste-to-energy thermal treatment, landfills still constitute the most common municipal solid waste management practice, especially in low-and-middle-income countries, and technological solutions to improve their environmental footprint are hereby presented. At the same time, remediation solutions are required to address the multitude of contaminated sites worldwide. Advanced developments that incorporate environmental, economic and social dimensions are expounded by the authors, together with sustainable ground improvement solutions for infrastructure projects conducted in soft and weak soils. The topic of thermo-active geostructures concludes this paper, where, apart from their infrastructure utility, these structures have the potential to contribute to the renewable energy source.Published versionThe second author would like to acknowledge the support of the Office of the Associate Provost for Research and Academic Development at Abu Dhabi University, UAE through grant19300540

Molecular and phylogenetic analysis of HIV-1 variants circulating in Italy

<p>Abstract</p> <p>Objective</p> <p>The continuous identification of HIV-1 non-B subtypes and recombinant forms in Italy indicates the need of constant molecular epidemiology survey of genetic forms circulating and transmitted in the resident population.</p> <p>Methods</p> <p>The distribution of HIV-1 subtypes has been evaluated in 25 seropositive individuals residing in Italy, most of whom were infected through a sexual route during the 1995–2005 period. Each sample has been characterized by detailed molecular and phylogenetic analyses.</p> <p>Results</p> <p>18 of the 25 samples were positive at HIV-1 PCR amplification. Three samples showed a nucleotide divergence compatible with a non-B subtype classification. The phylogenetic analysis, performed on both HIV-1 <it>env </it>and <it>gag </it>regions, confirms the molecular sub-typing prediction, given that 1 sample falls into the C subtype and 2 into the G subtype. The B subtype isolates show high levels of <it>intra</it>-subtype nucleotide divergence, compatible with a long-lasting epidemic and a progressive HIV-1 molecular diversification.</p> <p>Conclusion</p> <p>The Italian HIV-1 epidemic is still mostly attributable to the B subtype, regardless the transmission route, which shows an increasing nucleotide heterogeneity. Heterosexual transmission and the interracial blending, however, are slowly introducing novel HIV-1 subtypes. Therefore, a molecular monitoring is needed to follow the constant evolution of the HIV-1 epidemic.</p

Human T-lymphotropic virus type 1 (HTLV-1) prevalence and quantitative detection of DNA proviral load in individuals with indeterminate/positive serological results

BACKGROUND: HTLV-1 infection is currently restricted to endemic areas. To define the prevalence of HTLV-1 infection in patients living in Italy, we first carried out a retrospective serological analysis in a group of people originating from African countries referred to our hospital from January 2003 to February 2005. We subsequently applied a real time PCR on peripheral blood mononuclear cells from subjects with positive or indeterminate serological results. METHODS: All the sera were first analysed by serological methods (ELISA and/or Western Blotting) and then the peripheral blood mononuclear cells from subjects with positive or inconclusive serological results were analyzed for the presence of proviral DNA by a sensitive SYBR Green real time PCR. In addition, twenty HTLV-I ELISA negative samples were assayed by real time PCR approach as negative controls. RESULTS: Serological results disclosed serum reactivity by ELISA (absorbance values equal or greater than the cut-off value) in 9 out of 3408 individuals attending the Sexually Transmitted Diseases Clinic and/or Oncology Department, and 2 out 534 blood donors enrolled as a control population. Irrespective of positive or inconclusive serological results, all these subjects were analyzed for the presence of proviral DNA in peripheral blood mononuclear cells by SYBR real time PCR. A clear-cut positive result for the presence of HTLV-1 DNA was obtained in two subjects from endemic areas. CONCLUSION: SYBR real time PCR cut short inconclusive serological results. This rapid and inexpensive assay showed an excellent linear dynamic range, specificity and reproducibility readily revealing and quantifying the presence of virus in PBMCs. Our results highlight the need to monitor the presence of HTLV-1 in countries which have seen a large influx of immigrants in recent years. Epidemiological surveillance and correct diagnosis are recommended to verify the prevalence and incidence of a new undesirable phenomenon