[Unusual presentation of a mast cell tumor in the ear canal of a cat]. / Ungewöhnlicher Mastzelltumor im Gehörgang einer Katze.

A 12-year-old male neutered European Shorthair cat was presented for pruritus in the right ear region, bleeding from ear canal and a suspected polyp-like mass in its lumen.After the diagnostic imaging a biopsy of the mass was taken and submitted for histopathological evaluation. Histopathologic examination led to the diagnosis of low grade mast cell tumor. The subsequent staging examinations included ultrasonography of the liver and spleen as well as a complete blood count. Total ear canal ablation was performed on the same day, and the removed ear canal was again submitted for histopathologic evaluation of the surgical margins. The excision incision margins were free from infiltrating tumor cells. The cat was euthanised 14 months after the surgery. It is unknown whether the reasons for this were associated to metastatic spread of the initial mast cell tumor.A mast cell tumor in the ear canal is an unusual and rare finding, however it should be included in the list of differential diagnoses for ear canal tumors.

Sulfur disproportionation in deep COHS slab fluids drives mantle wedge oxidation.

Sulfur degassed at volcanic arcs calls for dissolved sulfate ions (S6+) released by subduction-zone fluids, oxidizing (in association with carbon) the subarc mantle, but sulfur speciation in subduction fluids at subarc depths remains unclear. We apply electrolytic fluid thermodynamics to model the dissolution behavior of pyrite in metacarbonate sediments as a function of P, T and rock redox state up to 4.3 gigapascals and 730°C. At subarc depth and the redox conditions of the fayalite-magnetite-quartz oxygen buffer, pyrite dissolution releases oxidized sulfur in fluids by disproportionation into sulfate, bisulfite, and sulfide species. These findings indicate that oxidized, sulfur-rich carbon-oxygen-hydrogen-sulfur (COHS) fluids form within subducting slabs at depths greater than 100 kilometers independent from slab redox state and that sulfur can be more effective than the concomitantly dissolved carbon at oxidizing the mantle wedge, especially when carbonates are stable.

Cultivation and sequencing-free protocol for Serratia marcescens detection and typing.

Serratia marcescens is an opportunistic pathogen that survives in inhospitable environments causing large outbreaks, particularly in neonatal intensive care units (NICUs). Genomic studies revealed that most S. marcescens nosocomial infections are caused by a specific clone (here "Infectious clone"). Whole genome sequencing (WGS) is the only portable method able to identify this clone, but it requires days to obtain results. We present a cultivation-free hypervariable-locus melting typing (HLMT) protocol for the fast detection and typing of S. marcescens, with 100% detection capability on mixed samples and a limit of detection that can reach the 10 genome copies. The protocol was able to identify the S. marcescens infectious clone with 97% specificity and 96% sensitivity when compared to WGS, yielding typing results portable among laboratories. The protocol is a cost and time saving method for S. marcescens detection and typing for large environmental/clinical surveillance screenings, also in low-middle income countries.

The diagnostic performances of the Atellica® 1500 automated urinalysis system for ruling out bacterial urinary tract infection.

Urinary tract infection (UTI) is one of the most common diseases occurring in both hospitalized and community subjects. Urine culture is the gold standard test for the diagnosis of UTI, but approximately 80% are negative. The aim of this study was to evaluate the performance of the automated urinalysis system Atellica® 1500 (Siemens Healthineers, Erlangen, Germany) as screening tool for ruling out UTI. A total of 5,490 urine specimens from outpatients, that had simultaneous requests for urinalysis and urine culture, were evaluated. Of the 5,490 samples, 833 (15.2 %) resulted positive for urine culture. Among UTI-related parameters, bacterial count was considered the most apt to be diagnostic of subjects affected by UTI. Using a cutoff value for bacteria count equal to 180 elements/µL, Atellica® 1500 detected bacteriuria with diagnostic sensitivity (Se) of 88.1 %, diagnostic specificity (Sp) of 82.1 %, and negative predictive value (NPV) of 95.2 %. Comparing our results with the literature's data, we observed that our Se and NPV were lower, while our Sp was higher. Our data showed that the Atellica® 1500 system detected bacteria with satisfactory analytical performance, but the results obtained do not make it a reliable tool for excluding UTI with urinalysis.

Hypervariable-Locus Melting Typing: a Novel Approach for More Effective High-Resolution Melting-Based Typing, Suitable for Large Microbiological Surveillance Programs.

Pathogen typing is pivotal to detecting the emergence of high-risk clones in hospital settings and to limit their spread. Unfortunately, the most commonly used typing methods (i.e., pulsed-field gel electrophoresis [PFGE], multilocus sequence typing [MLST], and whole-genome sequencing [WGS]) are expensive or time-consuming, limiting their application to real-time surveillance. High-resolution melting (HRM) can be applied to perform cost-effective and fast pathogen typing, but developing highly discriminatory protocols is challenging. Here, we present hypervariable-locus melting typing (HLMT), a novel approach to HRM-based typing that enables the development of more effective and portable typing protocols. HLMT types the strains by assigning them to melting types (MTs) on the basis of a reference data set (HLMT-assignment) and/or by clustering them using melting temperatures (HLMT-clustering). We applied the HLMT protocol developed on the capsular gene wzi for Klebsiella pneumoniae on 134 strains collected during surveillance programs in four hospitals. Then, we compared the HLMT results to those obtained using wzi, MLST, WGS, and PFGE typing. HLMT distinguished most of the K. pneumoniae high-risk clones with a sensitivity comparable to that of PFGE and MLST+wzi. It also drew surveillance epidemiological curves comparable to those obtained using MLST+wzi, PFGE, and WGS typing. Furthermore, the results obtained using HLMT-assignment were consistent with those of wzi typing for 95% of the typed strains, with a Jaccard index value of 0.9. HLMT is a fast and scalable approach for pathogen typing, suitable for real-time hospital microbiological surveillance. HLMT is also inexpensive, and thus, it is applicable for infection control programs in low- and middle-income countries. IMPORTANCE In this work, we describe hypervariable-locus melting typing (HLMT), a novel fast approach to pathogen typing using the high-resolution melting (HRM) assay. The method includes a novel approach for gene target selection, primer design, and HRM data analysis. We successfully applied this method to distinguish the high-risk clones of Klebsiella pneumoniae, one of the most important nosocomial pathogens worldwide. We also compared HLMT to typing using WGS, the capsular gene wzi, MLST, and PFGE. Our results show that HLMT is a typing method suitable for real-time epidemiological investigation. The application of HLMT to hospital microbiology surveillance can help to rapidly detect outbreak emergence, improving the effectiveness of infection control strategies.

A biomimetic approach to the chemical inactivation of chrysotile fibres by lichen metabolites.

Some lichens were recently reported to modify the surface state of asbestos. Here we report some new insight on the physico-chemical modifications induced by natural chelators (lichen metabolites) on two asbestos samples collected in two different locations. A biomimetic approach was followed by reproducing in the laboratory the weathering effect of lichen metabolites. Norstictic, pulvinic and oxalic acid (0.005, 0.5 and 50 mM) were put in contact with chrysotile fibres, either in pure form (A) or intergrown with balangeroite, an iron-rich asbestiform phase (B). Mg and Si removal, measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), reveals an incongruent dissolution for pure chrysotile (A), with Mg removal always exceeding that of Si, while chrysotile-balangeroite (B) follows a congruent dissolution pattern in all cases except in the presence of 50 mM oxalic acid. A much larger removal of Mg than Si in the solutions of 0.5 and 50 mM oxalic acid with chrysotile (A) suggests a structural collapse, which in the case of chrysotile-balangeroite (B) only occurs with 50 mM oxalic acid; in these cases both samples are converted into amorphous silica (as detected by X-ray diffraction (XRD)). Subsequent to incubation, some new phases (Fe(2)O(3), CaMg(CO(3))(2), Ca(C(2)O(4)) x H(2)O and Mg(C(2)O(4))2 x H(2)O), similar to those observed in the field, were detected by XRD and micro-Raman spectroscopy. The leaching effect of lichen metabolites also modifies the Fenton activity, a process widely correlated with asbestos pathogenicity: pure chrysotile (A) activity is reduced by 50 mM oxalic acid, while all lichen metabolites reduce the activity of chrysotile-balangeroite (B). The selective removal of poorly coordinated, highly reactive iron ions, evidenced by NO adsorption, accounts for the loss in Fenton activity. Such fibres were chemically close to the ones observed in the field. Chrysotile-rich rocks, colonised by lichens, could be exposed to a natural bioattenuation and considered as a transient environmental hazard.

Chrysotile asbestos is progressively converted into a non-fibrous amorphous material by the chelating action of lichen metabolites.

A natural deactivation of chrysotile asbestos occurs on serpentinite rocks where lichens selectively grow on the fibres and secrete metabolites, including oxalic acid, which, in the long term, turn the fibres into a non-toxic amorphous material.