Neuroimmune pathophysiology of long COVID.

Although COVID-19 was originally considered a respiratory illness, it is now well established that SARS-CoV-2 infection can have far-reaching impacts on the nervous system. Neurological symptoms such as chemosensory dysfunction are frequently observed during acute infection and approximately 10% of COVID-19 cases will go on to develop new or persistent long-term symptoms, a condition known in the literature as post-acute symptoms of COVID-19 (PASC) or by the patient-coined term Long COVID. Common neurological symptoms in Long COVID include new onset cognitive difficulties, dysautonomia, fatigue, and peripheral neuropathy.

Acclimation conditions and subsequent acute hypoxia challenges do not affect the frequency of erythrocyte nuclear segmentation in triploid brook charr Salvelinus fontinalis (Mitchill 1814).

Routine observations of blood smears have repeatedly shown that triploid fish have a greater proportion of erythrocytes with nuclear segmentation (ENS) than diploids; however, there is as yet no understanding of why this is the case and whether it affects erythrocyte function. In an attempt to address this, we examined blood smears from two previous experiments to determine whether ENS frequency is affected by rearing conditions (acclimation temperature or dissolved oxygen level) and subsequent acute aerobic distress in diploid and triploid brook charr Salvelinus fontinalis (Mitchill 1814). As expected, triploids had a higher ENS frequency than corresponding diploids, but with no biologically significant effect of experimental conditions on ENS frequency in triploids.

A Systematic Review and Meta-Analysis of Chemical Sanitizer Efficacy Against Biofilms of Listeria monocytogenes, Salmonella enterica, and STEC on Food Processing Surfaces.

Chemical sanitizers are applied to food processing surfaces to inactivate bacterial pathogens. Pathogen type, surface type along with sanitizer type, concentration, and contact time are important factors potentially impacting sanitation efficacy. Numerous studies on chemical agents and lab-generated biofilms have been published; however, cross-study comparisons can be difficult.

Online integration of capillary electrophoresis and dual detector Taylor dispersion analysis a 3D printed instrument.

Hydrodynamic radius () is a descriptive metric of protein structure with the potential to impact drug development, disease diagnosis, and other important research areas of molecular biology. Common instrumental methods for molecular size characterization are disadvantageous due to high sample consumption, measurements made in non-physiological conditions, and/or inaccurate size determinations. Capillary Taylor dispersion analysis (TDA) is a molecular sizing method that utilizes nL sample volumes and achieves absolute size determination without calibration or comparison to standards.

Real-time imaging of axonal membrane protein life cycles.

The construction of neuronal membranes is a dynamic process involving the biogenesis, vesicular packaging, transport, insertion and recycling of membrane proteins. Optical imaging is well suited for the study of protein spatial organization and transport. However, various shortcomings of existing imaging techniques have prevented the study of specific types of proteins and cellular processes.

Beyond antiviral: role of IFN-I in brain development.

Interferons and central nervous system resident macrophages, microglia, are well-known for their respective roles in antiviral defense and phagocytosis. Using a classic experimental paradigm for examining activity-dependent neural plasticity, Escoubas, Dorman, et al. recently identified a role for microglial type I interferon signaling in the clearance of unwanted neurons during mouse brain development.

Aqueous Ozone Efficacy for Inactivation of Foodborne Pathogens on Vegetables Used in Raw Meat-Based Diets for Companion Animals.

The present study evaluates the efficacy of a batch wash ozone sanitation system (BWOSS) and spray wash ozone sanitation system (SWOSS) against Listeria monocytogenes (two strains) and Salmonella enterica subsp. enterica (three serovars) inoculated on the surface of carrots, sweet potatoes, and butternut squash, commonly used in raw meat-based diets (RMBDs) marketed for companion animals such as dogs and cats. Produce either remained at room temperature for 2 h or were frozen at -20°C and then tempered overnight at 4°C to mimic the preprocessing steps of a raw pet food processing operation ('freeze-temper') prior to ozone treatment.

Sensitivity optimization of a rhodopsin-based fluorescent voltage indicator.

The ability to optically image cellular transmembrane voltages at millisecond-timescale resolutions can offer unprecedented insight into the function of living brains in behaving animals. Here, we present a point mutation that increases the sensitivity of Ace2 opsin-based voltage indicators. We use the mutation to develop Voltron2, an improved chemigeneic voltage indicator that has a 65% higher sensitivity to single APs and 3-fold higher sensitivity to subthreshold potentials than Voltron.

Draft Genome Sequences of 110 Shiga Toxin-Producing Escherichia coli Isolates Collected from Bovine Manure Samples in the Southern United States.

Shiga toxin-producing Escherichia coli (STEC) bacteria continue to impact the food industry. Environmental sampling of potential sources of contamination is important to aid epidemiologic efforts in tracking foodborne illnesses throughout the United States. Here, the draft genome sequences of 110 STEC isolates from bovine manure collected in Florida and Texas are reported.

Inflammation differentially controls transport of depolarizing Nav versus hyperpolarizing Kv channels to drive rat nociceptor activity.

Inflammation causes pain by shifting the balance of ionic currents in nociceptors toward depolarization, leading to hyperexcitability. The ensemble of ion channels within the plasma membrane is regulated by processes including biogenesis, transport, and degradation. Thus, alterations in ion channel trafficking may influence excitability.

Paclitaxel effects on axonal localization and vesicular trafficking of Na1.8.

Patients treated with paclitaxel (PTX) or other antineoplastic agents can experience chemotherapy-induced peripheral neuropathy (CIPN), a debilitating side effect characterized by numbness and pain. PTX interferes with microtubule-based transport, which inhibits tumor growth cell cycle arrest but can also affect other cellular functions including trafficking of ion channels critical to transduction of stimuli by sensory neurons of the dorsal root ganglia (DRG). We examined the effects of PTX on voltage-gated sodium channel Na1.

Surface Inactivation of a SARS-CoV-2 Surrogate with Hypochlorous Acid is Impacted by Surface Type, Contact Time, Inoculum Matrix, and Concentration.

Indirect contact with contaminated surfaces is a potential transmission route for COVID-19. Therefore, it is necessary to investigate convenient and inexpensive surface sanitization methods, such as HOCl, against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 surrogate, Phi6 (~ 7 log PFU/mL), was prepared in artificial saliva and tripartite matrices, spot inoculated on coupons of either stainless steel or vinyl, and allowed to dry.

Transfer of Phi6 bacteriophage between human skin and surfaces common to consumer-facing environments.

Aims: This study aimed to determine the extent of Phi6 (Φ6) transfer between skin and surfaces relevant to consumer-facing environments based on inoculum matrix, surface type and contact time.

Methods And Results: Φ6 transfer rates were determined from skin-to-fomite and fomite-to-skin influenced by inoculum matrix (artificial saliva and tripartite), surface type (aluminium, plastic, stainless steel, touchscreen, vinyl and wood) and contact time (5 and 10 s). Significant differences in estimated means were observed based on surface type (both transfer directions), inoculum matrix (skin-to-fomite) and contact time (both transfer directions).

Persistence of SARS-CoV-2 on surfaces and relevance to the food industry.

Determining the prevalence and persistence of viruses outside the human host aids our ability to characterize exposure risk across multiple transmission pathways. Since 2020, the Coronavirus Disease 2019 pandemic has resulted in a surge of research regarding severe acute respiratory syndrome-coronavirus-type 2 (SARS-CoV-2) and its potential to spread via direct and indirect contact transmission routes. Here, the authors discuss the current state of the science concerning SARS-CoV-2 transmission via contaminated surfaces and its persistence on environmental surfaces.

3D Printed Instrument for Taylor Dispersion Analysis with Two-Point Laser-Induced Fluorescence Detection.

Precisely controlling the size of engineered biomolecules and pharmaceutical compounds is often critical to their function. Standard methods for size characterization, such as dynamic light scattering or size exclusion chromatography, can be sample intensive and may not provide the sensitivity needed for mass- or concentration-limited biological systems. Taylor dispersion analysis (TDA) is a proven analytical method for direct, calibration-free size determination which utilizes only nL-pL sample volumes.

Factors Impacting Persistence of Phi6 Bacteriophage, an Enveloped Virus Surrogate, on Fomite Surfaces.

The persistence of Phi6 (Φ6) bacteriophage on surfaces commonly encountered in consumer-facing environments was evaluated. Φ6 has been utilized as a surrogate for enveloped viruses, including SARS-CoV-2-the causative agent of COVID-19-due to structural similarities, biosafety level 1 (BSL-1) status, and ease of use. Φ6 persistence on fomites was evaluated by characterizing the impact of the inoculum matrix (artificial saliva, phosphate-buffered saline [PBS], tripartite), inoculum level (low and high), and surface type (nonporous-aluminum, stainless steel, plastic, touchscreen, vinyl; porous-wood).

Synaptic connectivity to L2/3 of primary visual cortex measured by two-photon optogenetic stimulation.

Understanding cortical microcircuits requires thorough measurement of physiological properties of synaptic connections formed within and between diverse subclasses of neurons. Towards this goal, we combined spatially precise optogenetic stimulation with multicellular recording to deeply characterize intralaminar and translaminar monosynaptic connections to supragranular (L2/3) neurons in the mouse visual cortex. The reliability and specificity of multiphoton optogenetic stimulation were measured across multiple Cre lines, and measurements of connectivity were verified by comparison to paired recordings and targeted patching of optically identified presynaptic cells.

Phi 6 recovery from inoculated fingerpads based on elution buffer and methodology.

Phi 6 (Φ6) bacteriophage is a proposed surrogate to study pathogenic enveloped viruses including SARS-CoV-2-the causative agent of COVID-19-based on structural similarities, BSL-1 status, and ease of use. To determine the role of virus-contaminated hands in disease transmission, an enhanced understanding of buffer and method performance for Φ6 recovery needs to be determined. Four buffer types and three methodologies were investigated for the recovery of Φ6 from human fingerpads over a 30 min duration.

Influence of Free Chlorine and Contact Time on the Reduction of Salmonella Cross-Contamination of Tomatoes in a Model Flume System.

Abstract: The process of washing tomatoes in dump (flume) tanks has been identified as a potential source of cross-contamination. This study's objective was to assess the potential for Salmonella enterica cross-contamination at various inoculation levels in the presence of free chlorine (HOCl) and organic matter. Uninoculated tomatoes were introduced into a laboratory-based model flume containing tomatoes inoculated with a cocktail of five rifampin-resistant S.

Determining Bacterial Load and Water Quality Parameters of Chlorinated Tomato Flume Tanks in Florida Packinghouses.

Abstract: Monitoring and maintenance of water quality in dump tanks or flume systems is crucial to maintaining proper sanitizer levels to prevent pathogen cross-contamination during postharvest washing of tomatoes, but there is limited information on how organic matter influences sanitizer efficacy in the water. The main objective of this study was to monitor water quality in flume tanks and evaluate the efficacy of postharvest washing of tomatoes in commercial packinghouses. Flume tank water samples (n = 3) were collected on an hourly basis from three packinghouses in Florida and analyzed for pH, total dissolved solids (TDS), free chlorine, chemical oxygen demand (COD), oxidation-reduction potential, and turbidity.

Pathogen and Surrogate Survival in Relation to Fecal Indicator Bacteria in Freshwater Mesocosms.

The microbial quality of agricultural water for fresh produce production is determined by the presence of the fecal indicator bacterium (FIB) Escherichia coli, despite poor correlations with pathogen presence. Additional FIB, such as enterococci, have been utilized for assessing water quality. The study objective was to determine the survival times (first time to detect zero or censored) of FIB (E.

Taylor dispersion analysis in fused silica capillaries: a tutorial review.

Biological and pharmaceutical analytes like liposomes, therapeutic proteins, nanoparticles, and drug-delivery systems are utilized in applications, such as pharmaceutical formulations or biomimetic models, in which controlling their size is often critical. Many of the common techniques for sizing these analytes require method development, significant sample preparation, large sample quantities, and lengthy analysis times. In other cases, such as DLS, sizing can be biased towards the largest constituents in a mixture.

Autonomous Purkinje cell activation instructs bidirectional motor learning through evoked dendritic calcium signaling.

The signals in cerebellar Purkinje cells sufficient to instruct motor learning have not been systematically determined. Therefore, we applied optogenetics in mice to autonomously excite Purkinje cells and measured the effect of this activity on plasticity induction and adaptive behavior. Ex vivo, excitation of channelrhodopsin-2-expressing Purkinje cells elicits dendritic Ca transients with high-intensity stimuli initiating dendritic spiking that additionally contributes to the Ca response.

A microfluidic bubble perfusion device for brain slice culture.

Ex vivo brain slice cultures are utilized as analytical models for studying neurophysiology. Common approaches to maintaining slice cultures include roller tube and membrane interface techniques. The rise of organ-on-chip technologies has demonstrated the value of microfluidic perfusion culture systems for sampling and analysis of complex biology under well-controlled in vitro or ex vivo conditions.