CHARACTERIZATION AND REACTIVITY OF SILICATIC CONSOLIDANS

In this study some results on the reactivity of silicatic consolidants employed for the conservation of valuable artistic and cultural porous materials are discussed. In particular, a colloidal suspension of silica made by particles with an average diameter of 10– 15 nm, a sodium silicate and an ethyl silicate consolidant are studied. The chemical–physical characterization of xerogels achieved from the examined products were carried out determining the superficial area (BET method) and the average dimension of particles (SAXS) while the chemical structure of xerogels were investigated through NMR MAS spectroscopy of the 29Si nucleus. The investigation on reactivity between silica and stone support was executed by mixing consolidants with calcite and quartz powder to simplify as much as possible the system otherwise very complex. On silica produced by the three examined consolidants structural differences are revealed and these diversities can be responsible for the dissimilar reactivity of the silicatic systems towards the stone, in particular with regard to the carbonatic component

Low occurrence of digital ulcers in scleroderma patients treated with bosentan for pulmonary arterial hypertension: a retrospective case-control study.

Digital ulcers (DU) are one of the most common and debilitating manifestations of vasculopathy in systemic sclerosis (SSc). Their prevention is important in order to improve patients\u2019 outcome and as a result of the economic impact they have on society. Randomised controlled studies have demonstrated that bosentan, an endothelin receptor antagonist, reduces the appearance of new DU. The aim of this retrospective study was to evaluate the occurrence of DU in a group of patients receiving long-term bosentan treatment for pulmonary arterial hypertension associated with SSc (PAH-SSc). Patients with PAH-SSc and treated with bosentan for at least 6 months (n=30) were evaluated. Thirty patients with SSc not treated with bosentan, but matched for sex, age, disease duration and cutaneous form of SSc, were considered as a control group. The occurrence of DU, defined as loss of tissue of varying degrees in the epidermis, dermis and subcutaneous tissue, was determined in the bosentan-treated and untreated groups. Mean duration of bosentan treatment was 3.6 years. DU were detected in six patients in the bosentan-treated group (20.0 %) and 16 patients (53.3 %) in the untreated group (p=0.0015). There were no significant differences in demographic or clinical characteristics between patients with or without DU at study end. The occurrence of DU in patients with PAH-SSc receiving long-term bosentan treatment was significantly lower than in untreated patients. The results from this long-term observational study provide valuable information on management of patients with PAH-SSc

CAPILLAROSCOPIC SKIN ULCER RISK INDEX (CSURI) IN SYSTEMIC SCLEROSIS: RESULTS FROM AN ITALIAN MULTICENTER VALIDATION STUDY

Background: Digital ulcers (DU) represent one of the most frequent complications of microangiopathy in systemic sclerosis (SSc). Recently, we developed a capillaroscopic skin ulcers risk index (CSURI), to detect patients at risk to develop DU. CSURI takes into account maximum capillary diameter (D) in a videocapillaroscopic image, number of giant capillaries (M), and number of capillaries (N), following the formula: D × M/N2. CSURI showed a sensitivity and specificity of 94.3% and 85.9% respectively, at the cut-off value of 2.94, with an area under a ROC curve of 0.926.Objectives: Aim of our multicenter study is to validate the predictive value (PV) of CSURI in a larger series of SSc patients (pts).Methods: Two hundred and fifty-nine unselected SSc pts from 10 Italian rheumatologic centers were consecutively enrolled for the study during a six-month period. Capillaroscopic parameters were defined and collected according to our previous study. With regards to their clinical history of DU, 106 pts have never experienced DU, 63 have had DU more than one year before, 42 have experienced ulcers in the last year, while 48 pts presented DU at the baseline. All pts underwent videocapillaroscopy at baseline; after three-month follow-up, they were evaluated for the possible development or persistence of DU.Results: During the follow-up period, DU were observed in 71/259 pts; in particular, 48 subjects experienced new DU, whereas 23 pts showed the persistence of ulcers already present at the baseline. The ROC curve analysis showed an area under the curve of 0.861 (95%CI 0.812-0.901) for new ulcer appearance or non-healing ulcers, with specificity and sensitivity of 78.1% (95%CI 71.6–83.8) and 92.96% (95%CI 84.3–97.6) respectively, at the cut-off value of 2.96 (the positive and negative likelihood ratios were 4.26 and 0.09 respectively).The overall PV of CSURI was 61.7%. On the other hand, the negative PV was confirmed to be very high (96.7%), considering that only 5/152 pts with CSURI ≤2.96 had DU. Among pts with recent history of DU, 58.9% of them presented DU within 3 months by NVC. In this group, CSURI had a positive PV of 78.5% and a negative PV of 92%. With regard to the healing of DU, 23 pts continued to have DU 3 months and CSURI showed a negative PV of healing of 80.8%. On the contrary, 81.8% of the pts with CSURI <2.96 showed a regression of DU. Of interest, 15/18 pts without a recent history of DU, and with DU during the follow-up, were correctly identified by CSURI.Conclusions: This multicenter study confirms the high PV of CSURI, which is able to identify SSc pts at high risk to develop new DU. The introduction of this reliable tool in the clinical practice may permit the early detection of these pts, along with a better preventive treatment strategy and reduction of morbidity and social costs

Predictive role of capillaroscopic skin ulcer risk index in systematic sclerosis: a multicentre validation study

Introduction The early detection of systemic sclerosis (SSc) patients at high risk of developing digital ulcers could allow preventive treatment, with a reduction of morbidity and social costs. In 2009, a quantitative score, the capillaroscopic skin ulcer risk index (CSURI), calculated according to the formula 'D×M/N(2'), was proposed, which was highly predictive of the appearance of scleroderma digital ulcers within 3 months of capillaroscopic evaluation.OBJECTIVES:This multicentre study aims to validate the predictive value and reproducibility of CSURI in a large population of SSc patients.METHODS:CSURI was analysed in 229 unselected SSc patients by nailfold videocapillaroscopy (NVC). All patients were re-evaluated 3 months later with regard to the persistence and/or appearance of new digital ulcers.RESULTS:57 of 229 patients presented with digital ulcers after 3 months. The receiver operating characteristic curve analysis showed an area under the curve of 0.884 (95% CI 0.835 to 0.922), with specificity and sensitivity of 81.4% (95% CI 74.8 to 86.89) and 92.98% (95% CI 83.0 to 98.0), respectively, at the cut-off value of 2.96. The reproducibility of CSURI was validated on a random sample of 81 patients, with a κ-statistic measure of interrater agreement of 0.8514.CONCLUSIONS:The role of CSURI was confirmed in detecting scleroderma patients with a significantly high risk of developing digital ulcers within the first 3 months from NVC evaluation. CSURI is the only method validated to predict the appearance of digital ulcers and its introduction into routine clinical practice might help optimise the therapeutic strategy of these harmful SSc complications

Predictive role of capillaroscopic skin ulcer risk index in systemic sclerosis: a multicentre validation study

Introduction The early detection of systemic sclerosis (SSc) patients at high risk of developing digital ulcers could allow preventive treatment, with a reduction of morbidity and social costs. In 2009, a quantitative score, the capillaroscopic skin ulcer risk index (CSURI), calculated according to the formula 'D×M/N(2'), was proposed, which was highly predictive of the appearance of scleroderma digital ulcers within 3 months of capillaroscopic evaluation.OBJECTIVES: This multicentre study aims to validate the predictive value and reproducibility of CSURI in a large population of SSc patients. METHODS: CSURI was analysed in 229 unselected SSc patients by nailfold videocapillaroscopy (NVC). All patients were re-evaluated 3 months later with regard to the persistence and/or appearance of new digital ulcers. RESULTS: 57 of 229 patients presented with digital ulcers after 3 months. The receiver operating characteristic curve analysis showed an area under the curve of 0.884 (95% CI 0.835 to 0.922), with specificity and sensitivity of 81.4% (95% CI 74.8 to 86.89) and 92.98% (95% CI 83.0 to 98.0), respectively, at the cut-off value of 2.96. The reproducibility of CSURI was validated on a random sample of 81 patients, with a κ-statistic measure of interrater agreement of 0.8514. CONCLUSIONS: The role of CSURI was confirmed in detecting scleroderma patients with a significantly high risk of developing digital ulcers within the first 3 months from NVC evaluation. CSURI is the only method validated to predict the appearance of digital ulcers and its introduction into routine clinical practice might help optimise the therapeutic strategy of these harmful SSc complications

Diatom-based models for inferring water chemistry and hydrology in temporary depressional wetlands

Information on the response of temporary depressional wetland diatoms to human-induced disturbances is a limited and important component for the development of temporary wetland biological assessments in human-modified landscapes. Establishing a reference condition of variation due to natural disturbances in depressional wetlands using diatoms is necessary for further investigations of anthropogenic impacts. We examined the temporal and spatial responses of epiphytic diatom communities to natural environmental disturbances within three least disturbed wetlands in the Mpumalanga Province, South Africa. Alkalinity, Na+ and Cl−, water depth and total relative evapotranspiration (ETo) accounted for the highest proportion of temporal variation in composition of epiphytic diatoms, as revealed by canonical correspondence analysis (CCA). Alkalinity, Na+, and Cl− explained a much higher proportion of species variation, using partial CCA. A simple WA with inverse deshrinking produced reasonably robust models for Na+ (rboot2 = 0.71), depth (rboot2 = 0.64) and alkalinity (rboot2 = 0.46), not for Cl− and ETo. We determined species optima and tolerances for Na+, depth and alkalinity which can facilitate identification of anthropogenic impacts based on changes of indicator taxa assemblages. Our study provides a basis for newly developed quantitative tools to be used in biomonitoring studies and evaluations of reference conditions for temporary wetland management.Luisa Riato was supported by a Coaltech Research Association Research Fellowship.http://link.springer.com/journal/107502018-08-30hj2017Paraclinical Science