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SrMnSb$_2$ is suggested to be a magnetic topological semimetal. It contains square, 2D Sb planes with non-symmorphic crystal symmetries that could protect band crossings, offering the possibility of a quasi-2D, robust Dirac semi-metal in the form of a stable, bulk (3D) crystal. Here, we report a combined and comprehensive experimental and theoretical investigation of the electronic structure of SrMnSb$_2$, including the first ARPES data on this compound. SrMnSb$_2$ possesses a small Fermi surface originating from highly 2D, sharp and linearly dispersing bands (the Y-states) around the (0,$\pi$/a)-point in $k$-space. The ARPES Fermi surface agrees perfectly with that from bulk-sensitive Shubnikov de Haas data from the same crystals, proving the Y$-$states to be responsible for electrical conductivity in SrMnSb$_2$. DFT and tight binding (TB) methods are used to model the electronic states, and both show good agreement with the ARPES data. Despite the great promise of the latter, both theory approaches show the Y-states to be gapped above E$_F$, suggesting trivial topology. Subsequent analysis within both theory approaches shows the Berry phase to be zero, indicating the non-topological character of the transport in SrMnSb$_2$, a conclusion backed up by the analysis of the quantum oscillation data from our crystals.

Objectives: To improve the identification of anaerobic bacteria, the identity of clinical isolates which could not be identified using MALDI-TOF MS was assessed using whole genome sequencing (WGS) and in-house made main spectral profiles (MSPs) were created. Four novel Anaerococcus species, each represented by at least two isolates, were encountered., Methods: The novelty of the isolates was confirmed by comparing the 16S rRNA gene sequences and the WGS with their closest relatives. Phylogenetic and phylogenomic relationships were determined using MEGA X and DSMZ TYGS. Biochemical features were determined and the clustering of the created MSPs was calculated. Possible clinical relevance was assessed., Results: The novelty of the four different species was confirmed by the ANI value, and phylogenetic/phylogenomic clustering. Three of these species shared the same biochemical features, while one showed a different pattern. Only this latter species can be differentiated from other Anaerococcus spp. Remarkebly, six of the ten isolates were obtained from a positive blood culture, of which in five cases the bacterium was the only species encountered., Conclusions: We propose to name these novel species: Anaerococcus kampingiae (ENR0874 T  = DSM 117234 T , CCUG 77487 T (accession numbers PP192775/JBGMEF000000000)), Anaerococcus groningensis (ENR1011 T  = DSM 117232 T , CCUG 77488 T (accession numbers PP192777/JBGMEG000000000)), Anaerococcus martiniensis (ENR0831 T  = DSM 117233 T , CCUG 77486 T (accession numbers PP192776/JBGMEI000000000)), and Anaerococcus cruorum (ENR1039 T  = DSM 117235 T , CCUG 77489 T (accession numbers PP192778/JBGMEH000000000))., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Pets can have many positive effects on their owners. However, close contact with pets offers optimal conditions for transmission of micro-organisms. Especially immunocompromised patients are at risk for zoonotic infections. Here we describe the diagnosis, microbiology and treatment of three patients with severe zoonotic infections with Helicobacter canis, Pasteurella multocida and Capnocytophaga canimorsus . With this case report we would like to emphasize the importance of awareness for pet-related zoonotic infections in immunocompromised patients., (© 2022 The Authors.)

The majority of patients with neuroblastoma have tumors that initially respond to chemotherapy, but a large proportion will experience therapy-resistant relapses. The molecular basis of this aggressive phenotype is unknown. Whole-genome sequencing of 23 paired diagnostic and relapse neuroblastomas showed clonal evolution from the diagnostic tumor, with a median of 29 somatic mutations unique to the relapse sample. Eighteen of the 23 relapse tumors (78%) showed mutations predicted to activate the RAS-MAPK pathway. Seven of these events were detected only in the relapse tumor, whereas the others showed clonal enrichment. In neuroblastoma cell lines, we also detected a high frequency of activating mutations in the RAS-MAPK pathway (11/18; 61%), and these lesions predicted sensitivity to MEK inhibition in vitro and in vivo. Our findings provide a rationale for genetic characterization of relapse neuroblastomas and show that RAS-MAPK pathway mutations may function as a biomarker for new therapeutic approaches to refractory disease.