Axo-glial interactions between midbrain dopamine neurons and oligodendrocyte lineage cells in the anterior corpus callosum.

Oligodendrocyte progenitor cells (OPCs) receive synaptic innervation from glutamatergic and GABAergic axons and can be dynamically regulated by neural activity, resulting in activity-dependent changes in patterns of axon myelination. However, it remains unclear to what extent other types of neurons may innervate OPCs. Here, we provide evidence implicating midbrain dopamine neurons in the innervation of oligodendrocyte lineage cells in the anterior corpus callosum and nearby white matter tracts of male and female adult mice. Dopaminergic axon terminals were identified in the corpus callosum of DAT-Cre mice after injection of an eYFP reporter virus into the midbrain. Furthermore, fast-scan cyclic voltammetry revealed monoaminergic transients in the anterior corpus callosum, consistent with the anatomical findings. Using RNAscope, we further demonstrate that ~ 40% of Olig2 + /Pdfgra + cells and ~ 20% of Olig2 + /Pdgfra- cells in the anterior corpus callosum express Drd1 and Drd2 transcripts. These results suggest that oligodendrocyte lineage cells may respond to dopamine released from midbrain dopamine axons, which could affect myelination. Together, this work broadens our understanding of neuron-glia interactions with important implications for myelin plasticity by identifying midbrain dopamine axons as a potential regulator of corpus callosal oligodendrocyte lineage cells.

Real-Time, Multiplexed SHERLOCK for in Vitro Diagnostics.

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has highlighted the need for simple, low-cost, and scalable diagnostics that can be widely deployed for rapid testing. Clustered regularly interspaced short palindromic repeats (CRISPR)-based diagnostics have emerged as a promising technology, but its implementation in clinical laboratories has been limited by the requirement of a separate amplification step prior to CRISPR-associated (Cas) enzyme-based detection. This article reports the discovery of two novel Cas12 enzymes (SLK9 and SLK5-2) that exhibit enzymatic activity at 60°C, which, when combined with loop-mediated isothermal amplification (LAMP), enable a real-time, single-step nucleic acid detection method [real-time SHERLOCK (real-time SLK)]. Real-time SLK was demonstrated to provide accurate results comparable to those from real-time quantitative RT-PCR in clinical samples, with 100% positive and 100% negative percent agreement. The method is further demonstrated to be compatible with direct testing (real-time SLK Direct) of samples from anterior nasal swabs, without the need for standard nucleic acid extraction. Lastly, SLK9 was combined with either Alicyclobacillus acidoterrestris AacCas12b or with SLK5-2 to generate a real-time, multiplexed CRISPR-based diagnostic assay for the simultaneous detection of SARS-CoV-2 and a human-based control in a single reaction, with sensitivity down to 5 copies/µL and a time to result of under 30 minutes.

High-Throughput CRISPR-Cas13 SARS-CoV-2 Test.

BACKGROUND: The ability to control the spread of COVID-19 continues to be hampered by a lack of rapid, scalable, and easily deployable diagnostic solutions. METHODS: We developed a diagnostic method based on CRISPR (clustered regularly interspaced short palindromic repeats) that can deliver sensitive, specific, and high-throughput detection of Sudden Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2). The assay utilizes SHERLOCK (Specific High-sensitivity Enzymatic Reporter unLOCKing) for the qualitative detection of SARS-CoV-2 RNA and may be performed directly on a swab or saliva sample without nucleic acid extraction. The assay uses a 384-well format and provides results in <1 hour. RESULTS: Assay performance was evaluated with 105 (55 negative, 50 positive) remnant SARS-CoV-2 specimens previously tested using Food and Drug Administration emergency use authorized assays and retested with a modified version of the Centers for Disease Control and Prevention (CDC) quantitative PCR with reverse transcription (RT-qPCR) assay. When combined with magnetic bead-based extraction, the high-throughput SHERLOCK SARS-CoV-2 assay was 100% concordant (n = 60) with the CDC RT-qPCR. When used with direct sample addition the high-throughput assay was also 100% concordant with the CDC RT-qPCR direct method (n = 45). With direct saliva sample addition, the negative and positive percentage agreements were 100% (15/15, 95% CI: 81.8-100%) and 88% (15/17, 95% CI: 63.6-98.5%), respectively, compared with results from a collaborating clinical laboratory. CONCLUSIONS: This high-throughput assay identifies SARS-CoV-2 from patient samples with or without nucleic acid extraction with high concordance to RT-qPCR methods. This test enables high complexity laboratories to rapidly increase their testing capacities with simple equipment.

Pathogenicity of Enterococci.

Enterococci are unusually well adapted for survival and persistence in a variety of adverse environments, including on inanimate surfaces in the hospital environment and at sites of infection. This intrinsic ruggedness undoubtedly played a role in providing opportunities for enterococci to interact with other overtly drug-resistant microbes and acquire additional resistances on mobile elements. The rapid rise of antimicrobial resistance among hospital-adapted enterococci has rendered hospital-acquired infections a leading therapeutic challenge. With about a quarter of a genome of additional DNA conveyed by mobile elements, there are undoubtedly many more properties that have been acquired that help enterococci persist and spread in the hospital setting and cause diseases that have yet to be defined. Much remains to be learned about these ancient and rugged microbes, particularly in the area of pathogenic mechanisms involved with human diseases.

Miíase: uma experiência dramática em assistência de enfermagem / Myiasis: a dramatic experience in nursing assistance

Os autores relatam aspectos da assistência de enfermagem a um paciente internado com quadro grave e fatal de miíase na região central da face. Questionam a atenção primária dos serviços de saúde pública que ainda favorecem a ocorrência de casos extremos como esse.