Lithobiontic recolonization following cleaning and preservative treatments on the rock engravings of Valle Camonica, Italy: A 54-months monitoring

: Both the indirect control of microclimate conditions and the direct application of preservative products to contrast stone bioreceptivity may contribute to limit lithobiontic recolonization of cultural heritage surfaces after cleaning interventions. However, the priority deserved by these different preventive approaches has still been poorly evaluated, particularly in outdoor environments. This work dealt with the engraved sandstone surfaces of the National Park of Rock Engravings of Naquane (Italy, UNESCO WHS), widely colonized by lichens, mosses and a dark cyanobacterial biofilm, and thus requiring frequent cleaning interventions to preserve their legibility for visitors and scholars. In particular, post-cleaning recolonization by the different lithobionts was seasonally monitored along 54 months in different zones of an engraved outcrop, primarily differing in levels of shading, on parcels exposed to nine different conservative treatments. These included (or not) a pre-cleaning devitalization of lithobionts and the post-cleaning application of biocidal (benzalkonium chloride, plant essential oils, usnic acid) and other restoration products (nanocrystalline anatase, polysiloxane-based water repellent, ethyl-silicate-based consolidant). The combination of surface image analyses, fluorimetric and colorimetric measurements showed that mosses and the cyanobacterial biofilm rapidly recolonized all the parcels in the more shaded zone, irrespective of conservative treatments. In the other areas, recolonization significantly differed depending on the treatment. The post-cleaning application of biocides determined the best results through two vegetative seasons, but only nanocrystalline anatase and the polysiloxane-based water repellent maintained the surfaces lighter than uncleaned controls along the whole monitoring period. Recolonization primarily proceeded by the uncleaned surfaces surrounding the parcels and, at least in the examined case of lichens, did not show substantial shifts in community composition, although some nitrophytic species increased their frequency. In conclusion, the effectiveness of preservative treatments to prevent a rapid recolonization of heritage stone surfaces appeared subordinate to the presence of microenvironmental conditions less favourable to lithobionts

Litobionti e arte rupestre: strategie per la conservazione

Prova a guardare da vicino la superficie di una roccia esposta in ambiente esterno, che sia in un bosco o al bordo di una strada, in alta montagna, in prossimità del mare o anche in città: vedrai che è colonizzata da organismi viventi! Sono tanti e diversi fra loro per dimensioni e strategie di vita, nel loro complesso sono chiamati litobionti. I più grandi, ad esempio i muschi e i licheni, hanno per lo più dimensioni centimetriche e si vedono bene ad occhio nudo o con l’aiuto di una lente d’ingrandimento, mentre i più piccoli possono essere distinti solo con l'aiuto di un microscopio: sono cianobatteri, alghe verdi unicellulari e funghi neri a sviluppo microcoloniale. Questi microrganismi spesso si organizzano in biofilm ossia patine di vari colori spesso visibili sulle rocce; avvolti da una matrice gelatinosa che li protegge dagli agenti esterni, convivono tanti organismi diversi sia autotrofi che eterotrofi. Continua a leggere..

Aplastic anaemia in childhood. Description of two cases and review of the literature

AbstractChildhood aplastic anaemia (AA) is an uncommon but potentially fatal haematological disorder. Patients with AA receive supportive care based on transfusions and timely treatment of opportunistic infections, along with specific therapies, which may be bone marrow transplantation and immunosuppressive therapy. Early diagnosis and supportive therapy are required to prevent fatal complications like overwhelming sepsis or life threatening haemorrhages. We report two cases of aplastic anaemia having a different aetiology. The diagnostic work-up and the therapeutic management for each case are described below

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Use of larvae of the wax moth Galleria mellonella as an in vivo model to study the virulence of Helicobacter pylori.

Background: Helicobacter pylori is the first bacterium formally recognized as a carcinogen and is one of the most successful human pathogens, as over half of the world’s population is colonized by the bacterium. H. pylori-induced gastroduodenal disease depends on the inflammatory response of the host and on the production of specific bacterial virulence factors. The study of Helicobacter pylori pathogenic action would greatly benefit by easy-to-use models of infection. Results: In the present study, we examined the effectiveness of the larvae of the wax moth Galleria mellonella as a new model for H. pylori infection. G. mellonella larvae were inoculated with bacterial suspensions or broth culture filtrates from either different wild-type H. pylori strains or their mutants defective in specific virulence determinants, such as VacA, CagA, CagE, the whole pathogenicity island (PAI) cag, urease, and gamma-glutamyl transpeptidase (GGT). We also tested purified VacA cytotoxin. Survival curves were plotted using the Kaplan-Meier method and LD50 lethal doses were calculated. Viable bacteria in the hemocoel were counted at different time points post-infection, while apoptosis in larval hemocytes was evaluated by annexin V staining. We found that wild-type and mutant H. pylori strains were able to survive and replicate in G. mellonella larvae which underwent death rapidly after infection. H. pylori mutant strains defective in either VacA, or CagA, or CagE, or cag PAI, or urease, but not GGT-defective mutants, were less virulent than the respective parental strain. Broth culture filtrates from wild-type strains G27 and 60190 and their mutants replicated the effects observed using their respective bacterial suspension. Also, purified VacA cytotoxin was able to kill the larvae. The killing of larvae Always correlated with the induction of apoptosis in hemocytes. Conclusions: G. mellonella larvae are susceptible to H. pylori infection and may represent an easy to use in vivo model to identify virulence factors and pathogenic mechanisms of H. pylori. The experimental model described can be useful to screen a large number of clinical H. pylori strain and to correlate virulence of H. pylori strains with patients’ disease status

Il riparo del Cuel (Cimbergo, BS) tra frequentazione protostorica e pitture parietali

Between 2008 and 2015 the Soprintendenza Archeologia della Lombardia performed two excavation campaigns at the Cuel rockshelter, located in the municipal area of Cimbergo, in Valle Camonica (BS), known since the 1990s for two painted figures on top of the rock wall, right above the shelter. This paper presents new unpublished data from the diggings, along with the results of the analyses on the sediments and a 14C dating, a typological analysis of the material culture and a stylistic consideration of the painted figures. The excavations documented a sequence of 4 phases of frequentation: the first human presence is evidenced by a carbonaceous layer and several copper slag, dated to the 9th-8th centuries BCE. After a hiatus, the site was re-occupied in the 6th century BCE, and a sequence of five fireplaces, all constructed in the same peculiar fashion, were created inside the small shelter. The close proximity of these structures, along with their particular shape and the analyses carried out on their contents, suggests that their use was somehow related to some sort of cultic or symbolic occurrence. The painted figures on top of the rock, which do not have physical contact with the archaeological layers, are painted in red, and depict a deer with semi-folded legs and short antlers along with an almost fully erased anthropomorphic figure. These figures are stylistically akin to other painted scenes in the area of Paspardo, which are dated to the final Iron Age (2nd-1st century BC), so there is no clear chronological link between the material use at the site and the paintings. The last stage of habitation appears to be from the middle ages, dated from the find of a silver coin found in the 2008 excavations