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Human mpox is caused by the Monkeypox virus, a microorganism closely related to the Variola virus, both belonging to the Orthopoxvirus genus. Mpox had been considered a rare disease until a global outbreak occurred in 2022. People infected with the virus present similar symptoms to patients suffering smallpox and other rash illnesses, hindering diagnosis. The WHO indicated that no commercial PCR or serology kits are currently widely available. In the present study, the MPXV MONODOSE dtec-qPCR kit was validated following guidelines of the UNE/EN ISO/IEC 17025:2005. The parameters evaluated for the acceptance of the assay were in silico and in vitro specificity, quantitative phase analysis, reliability, and sensitivity. The assay passed validation criteria and yielded an efficiency of 95.8%, high repeatability, reproducibility, and a Limit of Detection and Quantification of at least 10 copies. Results from the validation of the MPXV dtec-qPCR kit were satisfactory. The use of the MONODOSE format (dehydrated single PCR-tubes, ready to use) provided considerable advantages allowing the detection of the Monkeypox virus to be accurately achieved. This detection kit may be considered a reliable, fast, simple, and universally available option. [ABSTRACT FROM AUTHOR]

Summary: Candida auris is an emerging multidrug resistant pathogenic fungus that causes candidaemia with high mortality rates and exhibits the ability to persist within the hospital environment. Candida auris is phylogenetically closely related to Candida haemulonii, C. lusitaniae, C. pseudohaemulonii and C. duobushaemulonii and is frequently misidentified by commercial identification methods. In the present study, the GPS™MONODOSE dtec‐qPCR kit (dried single‐dose PCR tubes) for the detection of C. auris was validated following the guidelines of the UNE/EN ISO/IEC 17025:2005, the French Standard NF T90‐471:2010 and using fast‐cycling protocols. Validation terms included in vitro specificity (inclusivity/exclusivity), quantitative phase analysis (10‐106 standard DNA copies), reliability (repeatability/reproducibility) and sensitivity (detection/quantification limits). GPS™ dtec‐qPCR kits passed validation with strict acceptance criteria (n ≥ 10 repetitions). In silico specificity was proven by the designer (GPS™). Experimental inclusiveness was achieved in two independent laboratories by testing strain JCM15448T and 117 clinical C. auris isolates from Asia, the Middle‐East Africa, Latin America and Europe. Exclusiveness was evaluated with 25 strains of closely related Candida spp. Use of the MONODOSE format provided considerable advantages allowing the detection of C. auris to be accurately achieved in less than an hour. The GPS™MONODOSE dtec‐qPCR kit is ready to undergo clinical evaluation. [ABSTRACT FROM AUTHOR]

A new species of the genus Aeromonas, Aeromonas sharmana sp. nov., was recently described on the basis of a single isolate, strain GPTSA-6⊃ T, obtained from a warm spring in India. The description of this new species included biochemical characterization, antibiotic susceptibility, cellular fatty-acid profiles, and 16S rRNA gene sequencing, but not DNADNA hybridization data. In the present article, phylogenetic analysis (branch distances in the tree and nucleotide signatures) of the 16S rRNA of isolate GPTSA-⊃ T, together with certain phenotypic characteristics of the isolate reported in the earlier description, clearly indicate that this microorganism does not belong to the genus Aeromonas as known to date, although it falls within the radiation of the family Aeromonadaceae. Emendation from the List of Prokaryotic Names with Standing in Nomenclature is consequently propose [ABSTRACT FROM AUTHOR]

The taxonomy of the "Aeromonas hydrophila" complex (comprising the species A. hydrophila, A. bestiarum, A. salmonicida, and A. popoffii) has been controversial, particularly the relationship between the two relevant fish pathogens A. salmonicida and A. bestiarum. In fact, none of the biochemical tests evaluated in the present study were able to separate these two species. One hundred and sixteen strains belonging to the four species of this complex were identified by 16S rDNA restriction fragment length polymorphism (RFLP). Sequencing of the 16S rDNA and cluster analysis of the 16S--23S intergenic spacer region (ISR)-RFLP in selected strains of A. salmonicida and A. bestiarum indicated that the two species may share extremely conserved ribosomal operons and demonstrated that, due to an extremely high degree of sequence conservation, 16S rDNA cannot be used to differentiate these two closely related species. Moreover, DNA--DNA hybridization similarity between the type strains of A. salmonicida subsp. salmonicida and A. bestiarum was 75.6 %, suggesting that they may represent a single taxon. However, a clear phylogenetic divergence between A. salmonicida and A. bestiarum was ascertained from an analysis based on gyrB and rpoD gene sequences, which provided evidence of a lack of congruence of the results obtained from 16S rDNA, 16S--23S ISR-RFLP, DNA--DNA pairing, and biochemical profiles. [ABSTRACT FROM AUTHOR]

Characterization of 999 Aeromonas strains using a published 16S rDNA RFLP identification method showed that 8.1% of the strains produced unexpected (hereafter called "atypical") restriction patterns, making their identification uncertain. Atypical patterns were due to the presence of nucleotide polymorphisms among the rrn operons of the 16S rRNA gene (so-called microheterogeneities). Double sequencing signals at certain positions revealed the nucleotide composition was responsible for the microheterogeneities. Although the number of microheterogeneities was relatively low (0.06-0.66%), trees inferred from the 16S rRNA gene led either to a misidentification or to an inconclusive result for the majority of these strains. Strains with atypical patterns were, however, correctly identified using the rpoD gene sequences, as belonging to Aeromonas caviae, A. veronii, and A. media. All of them, but particularly the two former species, are associated with human disease. Microheterogeneities in 16S rRNA gene sequence were significantly (P < 0.01) more prevalent in clinical than in environmental strains. This work also analyzed the effects of these microheterogeneities on the taxonomic position of the investigated strains. The results suggest the need for recording microheterogeneities in the 16S rRNA gene. [ABSTRACT FROM AUTHOR]

Candida auris is a multidrug-resistant pathogenic ascomycete yeast of increasing health concern. C. auris colonizes patient's skin and can persist for weeks on surfaces, so it can be transmitted within and between hospitals. The most common diagnostic platforms in microbiology use reference databases that have not yet incorporated C. auris, misidentifying it. This chapter describes how to detect C. auris by qPCR with the GPS™ CanAur MONODOSE dtec-qPCR Test (Alicante, Spain) in less than 45 min, using ready-to-use tubes with all the components dehydrated. This commercial kit was subjected to validation following the guidelines of the UNE-EN ISO/IEC 17025:2005 and French Standard NF T90-471:2010., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Candida auris is an emerging multidrug resistant pathogenic fungus that causes candidaemia with high mortality rates and exhibits the ability to persist within the hospital environment. Candida auris is phylogenetically closely related to Candida haemulonii, C. lusitaniae, C. pseudohaemulonii and C. duobushaemulonii and is frequently misidentified by commercial identification methods. In the present study, the GPS ™ MONODOSE dtec-qPCR kit (dried single-dose PCR tubes) for the detection of C. auris was validated following the guidelines of the UNE/EN ISO/IEC 17025:2005, the French Standard NF T90-471:2010 and using fast-cycling protocols. Validation terms included in vitro specificity (inclusivity/exclusivity), quantitative phase analysis (10-10 6  standard DNA copies), reliability (repeatability/reproducibility) and sensitivity (detection/quantification limits). GPS ™ dtec-qPCR kits passed validation with strict acceptance criteria (n ≥ 10 repetitions). In silico specificity was proven by the designer (GPS ™ ). Experimental inclusiveness was achieved in two independent laboratories by testing strain JCM15448 T and 117 clinical C. auris isolates from Asia, the Middle-East Africa, Latin America and Europe. Exclusiveness was evaluated with 25 strains of closely related Candida spp. Use of the MONODOSE format provided considerable advantages allowing the detection of C. auris to be accurately achieved in less than an hour. The GPS ™ MONODOSE dtec-qPCR kit is ready to undergo clinical evaluation., (© 2018 Blackwell Verlag GmbH.)

A new species of the genus Aeromonas, Aeromonas sharmana sp. nov., was recently described on the basis of a single isolate, strain GPTSA-6T, obtained from a warm spring in India. The description of this new species included biochemical characterization, antibiotic susceptibility, cellular fatty-acid profiles, and 16S rRNA gene sequencing, but not DNADNA hybridization data. In the present article, phylogenetic analysis (branch distances in the tree and nucleotide signatures) of the 16S rRNA of isolate GPTSA-6T, together with certain phenotypic characteristics of the isolate reported in the earlier description, clearly indicate that this microorganism does not belong to the genus Aeromonas as known to date, although it falls within the radiation of the family Aeromonadaceae. Emendation from the List of Prokaryotic Names with Standing in Nomenclature is consequently proposed.

Bacterial infections caused by members of the genus Aeromonas, with a relatively high antibiotic resistance, are among the most common and troublesome diseases of fish raised in ponds with recirculation systems. In this study, carried out at an experimental aquaculture station in northern Portugal, 51 strains identified as belonging to the genus Aeromonas were isolated from 20 rainbow trout (Oncorhynchus mykiss) skin and kidney samples, as well as from raceway water samples. Macro- and microscopic examination of the fish tissues revealed lesions or cellular alterations in skin and kidney that seemed to correlate with the presence of those isolates. The sensitivity of all isolated strains to different groups of beta-lactam antibiotics (penicillins, cephalosporins, monobactams and carbapenems) was evaluated using the disc diffusion method. The highest rates of resistance were to amoxicillin, carbenicillin and ticarcillin. Unexpected resistance to imipenem, an antibiotic of clinical usage, was also detected, which suggests that resistance may have been transferred to the Aeromonas population from the environment.