Visualizing the human olfactory projection and ancillary structures in a 3D reconstruction.

Visualizing in 3D the histological microanatomy of the human olfactory projection from the olfactory mucosa in the nasal cavity to the olfactory bulbs in the cranial cavity necessitates a workflow for handling a great many sections. Here, we assembled a 3D reconstruction of a 7.45 cm en-bloc specimen extracted from an embalmed human cadaver.

Protocol for postmortem bedside endoscopic procedure to sample human respiratory and olfactory cleft mucosa, olfactory bulbs, and frontal lobe.

We present a protocol for the rapid postmortem bedside procurement of selected tissue samples using an endoscopic endonasal surgical technique that we adapted from skull base surgery. We describe steps for the postmortem collection of blood, cerebrospinal fluid, a nasopharyngeal swab, and tissue samples; the clean-up procedure; and the initial processing and storage of the samples. This protocol was validated with tissue samples procured postmortem from COVID-19 patients and can be applied in another emerging infectious disease.

Visualising SARS-CoV-2 infection of the lung in deceased COVID-19 patients.

Background: SARS-CoV-2 is a single-stranded positive-sense RNA virus. Several negative-sense SARS-CoV-2 RNA species, both full-length genomic and subgenomic, are produced transiently during viral replication. Methodologies for rigorously characterising cell tropism and visualising ongoing viral replication at single-cell resolution in histological sections are needed to assess the virological and pathological phenotypes of future SARS-CoV-2 variants.

Anatomical barriers against SARS-CoV-2 neuroinvasion at vulnerable interfaces visualized in deceased COVID-19 patients.

Can SARS-CoV-2 hitchhike on the olfactory projection and take a direct and short route from the nose into the brain? We reasoned that the neurotropic or neuroinvasive capacity of the virus, if it exists, should be most easily detectable in individuals who died in an acute phase of the infection. Here, we applied a postmortem bedside surgical procedure for the rapid procurement of tissue, blood, and cerebrospinal fluid samples from deceased COVID-19 patients infected with the Delta, Omicron BA.1, or Omicron BA.

Lung epithelial and myeloid innate immunity in influenza-associated or COVID-19-associated pulmonary aspergillosis: an observational study.

Background: Influenza-associated pulmonary aspergillosis (IAPA) and COVID-19-associated pulmonary aspergillosis (CAPA) affect about 15% of critically ill patients with influenza or COVID-19, respectively. These viral-fungal coinfections are difficult to diagnose and are associated with increased mortality, but data on their pathophysiology are scarce. We aimed to explore the role of lung epithelial and myeloid innate immunity in patients with IAPA or CAPA.

Visualizing in deceased COVID-19 patients how SARS-CoV-2 attacks the respiratory and olfactory mucosae but spares the olfactory bulb.

Anosmia, the loss of smell, is a common and often the sole symptom of COVID-19. The onset of the sequence of pathobiological events leading to olfactory dysfunction remains obscure. Here, we have developed a postmortem bedside surgical procedure to harvest endoscopically samples of respiratory and olfactory mucosae and whole olfactory bulbs.

A Prosthetically Guided Technique for Cast Post-and-Core Fabrication.

Despite it being an older, conventional production method, the cast metal post and core is still often considered the best option for the restoration of severely damaged teeth. The direct technique for fabrication of cast post-and-core patterns, however, can pose challenges due to the inefficiencies and guesswork involved in creating an appropriate form and dimension for the core segment. This article presents an enhanced technique for cast post-and-core fabrication in reference to the desired dimensions of the final restoration.

Danger perception and stress response through an olfactory sensor for the bacterial metabolite hydrogen sulfide.

The olfactory system serves a critical function as a danger detection system to trigger defense responses essential for survival. The cellular and molecular mechanisms that drive such defenses in mammals are incompletely understood. Here, we have discovered an ultrasensitive olfactory sensor for the highly poisonous bacterial metabolite hydrogen sulfide (HS) in mice.

Investigation of the Cellular Destination of Fluorescently Labeled Carbon Nanohorns in Cultured Cells.

The high surface area, facile functionalization, and biocompatibility of carbon nanohorns (CNHs) make them attractive for many applications, including drug delivery. The cellular destination of nanomaterials dictates both the therapeutic application and the potential toxicity. Identifying the uptake mechanism is challenging as several endocytic pathways have been identified that facilitate cellular entry.

Expert curation of the human and mouse olfactory receptor gene repertoires identifies conserved coding regions split across two exons.

Background: Olfactory receptor (OR) genes are the largest multi-gene family in the mammalian genome, with 874 in human and 1483 loci in mouse (including pseudogenes). The expansion of the OR gene repertoire has occurred through numerous duplication events followed by diversification, resulting in a large number of highly similar paralogous genes. These characteristics have made the annotation of the complete OR gene repertoire a complex task.

A transcriptomic atlas of mammalian olfactory mucosae reveals an evolutionary influence on food odor detection in humans.

The mammalian olfactory system displays species-specific adaptations to different ecological niches. To investigate the evolutionary dynamics of olfactory sensory neuron (OSN) subtypes across mammalian evolution, we applied RNA sequencing of whole olfactory mucosa samples from mouse, rat, dog, marmoset, macaque, and human. We find that OSN subtypes, representative of all known mouse chemosensory receptor gene families, are present in all analyzed species.

The testicular soma of Tsc22d3 knockout mice supports spermatogenesis and germline transmission from spermatogonial stem cell lines upon transplantation.

Spermatogonial stem cells (SSCs) are adult stem cells that are slowly cycling and self-renewing. The pool of SSCs generates very large numbers of male gametes throughout the life of the individual. SSCs can be cultured in vitro for long periods of time, and established SSC lines can be manipulated genetically.

Comparison of Label and Laboratory Sodium Values in Popular Sodium-Contributing Foods in the United States.

Background: Nutrition labels are important tools for consumers and for supporting public health strategies. Recent, published comparison of label and laboratory sodium values for US foods, and differences by brand type (national or private-label) or source (store or restaurant [fast-food and sit-down]) is unavailable.

Objective: The objective was to compare label and laboratory values for sodium and related nutrients (ie, total sugars, total fat, and saturated fat) in popular, sodium-contributing foods, and examine whether there are differences by brand type, and source.

PDGFRA Is Not Essential for the Derivation and Maintenance of Mouse Extraembryonic Endoderm Stem Cell Lines.

Extraembryonic endoderm stem (XEN) cell lines can be derived and maintained in vitro and reflect the primitive endoderm lineage. Platelet-derived growth factor receptor alpha (PDGFRA) is thought to be essential for the derivation and maintenance of mouse XEN cell lines. Here, we have re-evaluated this requirement for PDGFRA.

Efficient derivation of extraembryonic endoderm stem cell lines from mouse postimplantation embryos.

Various types of stem cell lines have been derived from preimplantation or postimplantation mouse embryos: embryonic stem cell lines, epiblast stem cell lines, and trophoblast stem cell lines. It is not known if extraembryonic endoderm stem (XEN) cell lines can be derived from postimplantation mouse embryos. Here, we report the derivation of 77 XEN cell lines from 85 postimplantation embryos at embryonic day E5.

Neuropilin-1 and the Positions of Glomeruli in the Mouse Olfactory Bulb.

It is known since 1996 that mouse odorant receptors (ORs) are involved in determining the positions of the sites of coalescence of axons of olfactory sensory neurons (OSNs)-the thousands of glomeruli in the olfactory bulb. But the molecular and cellular mechanisms of OR-mediated axonal coalescence into glomeruli remain unclear. A model was proposed in 2006-2009 whereby OR-derived cAMP signals, rather than direct action of OR molecules, determine the target destinations (glomeruli) of OSNs in the bulb.

Exclusive transmission of the embryonic stem cell-derived genome through the mouse germline.

Gene targeting in embryonic stem (ES) cells remains best practice for introducing complex mutations into the mouse germline. One aspect in this multistep process that has not been streamlined with regard to the logistics and ethics of mouse breeding is the efficiency of germline transmission: the transmission of the ES cell-derived genome through the germline of chimeras to their offspring. A method whereby male chimeras transmit exclusively the genome of the injected ES cells to their offspring has been developed.

Hierarchical deconstruction of mouse olfactory sensory neurons: from whole mucosa to single-cell RNA-seq.

The mouse olfactory mucosa is a complex chemosensory tissue composed of multiple cell types, neuronal and non-neuronal. We have here applied RNA-seq hierarchically, in three steps of decreasing cellular heterogeneity: starting with crude tissue samples dissected from the nose, proceeding to flow-cytometrically sorted pools of mature olfactory sensory neurons (OSNs), and finally arriving at single mature OSNs. We show that 98.

The extremely broad odorant response profile of mouse olfactory sensory neurons expressing the odorant receptor MOR256-17 includes trace amine-associated receptor ligands.

The mouse olfactory system employs ~1100 G-protein-coupled odorant receptors (ORs). Each mature olfactory sensory neuron (OSN) is thought to express just one OR gene, and the expressed OR determines the odorant response properties of the OSN. The broadest odorant response profile thus far demonstrated in native mouse OSNs is for OSNs that express the OR gene SR1 (also known as Olfr124 and MOR256-3).

Sodium monitoring in commercially processed and restaurant foods.

Background: Most sodium in the US diet comes from commercially processed and restaurant foods. Sodium reduction in these foods is key to several recent public health efforts.

Objective: The objective was to provide an overview of a program led by the USDA, in partnership with other government agencies, to monitor sodium contents in commercially processed and restaurant foods in the United States.

A family of nonclassical class I MHC genes contributes to ultrasensitive chemodetection by mouse vomeronasal sensory neurons.

The mouse vomeronasal organ (VNO) has a pivotal role in chemical communication. The vomeronasal sensory neuroepithelium consists of distinct populations of vomeronasal sensory neurons (VSNs). A subset of VSNs, with cell bodies in the basal part of the basal layer, coexpress Vmn2r G-protein-coupled receptor genes with H2-Mv genes, a family of nine nonclassical class I major histocompatibility complex genes.

Statistical analysis of differential gene expression relative to a fold change threshold on NanoString data of mouse odorant receptor genes.

Background: A challenge in gene expression studies is the reliable identification of differentially expressed genes. In many high-throughput studies, genes are accepted as differentially expressed only if they satisfy simultaneously a p value criterion and a fold change criterion. A statistical method, TREAT, has been developed for microarray data to assess formally if fold changes are significantly higher than a predefined threshold.