Narrative Medicine Theory and Practice: the Double Helix Model.

The genesis of the medical humanities as a discrete academic discipline engendered a need for a theoretical framework, a function taken on by the growing narrative medicine movement. More recently, scholars have begun to develop a critical medical humanities, an analytical movement that emphasises the fundamental enmeshment of the sciences and humanities. Building on Helene Scott-Fordsmand's work on reversing the medical humanities, this paper develops an alternative to the current version of narrative medicine. We propose a new interpretive heuristic, the Double Helix Model, and place it in critical dialogue with the Columbia School's close reading based-approach. Through this new conceptual frame, we suggest that critical narrative medicine may empower clinicians to contribute to the reorientation of the roles of the sciences and humanities, benefiting providers, scholars and patients.

Inflammatory bowel disease patients undergoing total hip arthroplasty have higher odds of implant-related complications.

PURPOSE: This study evaluates whether IBD patients are at increased risk of implant-related complications after THA. MATERIALS AND METHODS: A retrospective study from 01 January 2010 to 31 October 31 2020 using an administrative claims database was performed. IBD patients undergoing THA (n = 11,025), without corticosteroid treatment, were propensity score matched to controls in a 1:5 ratio (n = 55,121) based on age, sex, and the Charlson Comorbidity Index (CCI). Outcomes evaluated included periprosthetic fracture, aseptic loosening, prosthetic joint infection, and THA revision within 2 years of index procedure. Chi-square analyses were used to compare the matched cohorts. The association of IBD and implant-related complications was evaluated using logistical regression to calculate odds ratios (ORs), 95% confidence intervals (95% CIs), and p-values. A p-value < 0.001 was used as the significance threshold. RESULTS: Patients with IBD had a greater incidence and odds of total implant complications (7.03% vs. 3.98%; OR 1.76; p < 0.001) compared with matched controls. IBD patients had significantly higher incidence and odds of developing periprosthetic fracture (0.50% vs. 0.20%; OR 2.46; p < 0.001), THA revisions (2.21% vs. 1.17%; OR 1.91; p < 0.001), aseptic loosening (1.45% vs. 0.84%; OR 1.75; p < 0.001), and prosthetic joint infection (2.87% vs. 1.77%; OR 1.64; p < 0.001). CONCLUSIONS: Patients with IBD who underwent primary THA had a significantly higher risk of implant-related complications compared to matched controls. Providers should use this study to appropriately assess post-complication risk factors for their patients with IBD.

Retbindin mediates light-damage in mouse retina while its absence leads to premature retinal aging.

Vision requires the transport and recycling of the pigment 11-cis retinaldehyde (retinal) between the retinal pigment epithelium (RPE) and photoreceptors. 11-cis retinal is also required for light-mediated photoreceptor death in dark-adapted mouse eye, probably through overstimulation of rod cells adapted for low light. Retbindin is a photoreceptor-specific protein, of unclear function, that is localized between the RPE and the tips of the photoreceptors. Unexpectedly, young Rtbdn-KO mice, with targeted deletion (KO) of retbindin, showed delayed regeneration of retinal function after bleaching and were strongly resistant to light-induced photoreceptor death. Furthermore, bio-layer interferometry binding studies showed recombinant retbindin had significant affinity for retinoids, most notably 11-cis retinal. This suggests that retbindin mediates light damage, probably through a role in transport of 11-cis retinal. In Rtbdn-KO mice, retinal development was normal, as were amplitudes of rod and cone electroretinograms (ERG) up to 4 months, although implicit times and c-waves were affected. However, with aging, both light- and dark-adapted ERG amplitudes declined significantly and photoreceptor outer segments became disordered, However, in contrast to other reports, there was little retinal degeneration or drop in flavin levels. The RPE developed vacuoles and lipid, protein and calcium deposits reminiscent of age-related macular degeneration. Other signs of premature aging included loss of OPN4+ retinal ganglion cells and activation of microglia. Thus, retbindin plays an unexpected role in the mammalian visual cycle, probably as an adaptation for vision in dim light. It mediates light damage in the dark-adapted eye, but also plays a role in light-adapted responses and in long term retinal homeostasis.

Male rainbow darters (Etheostoma caeruleum) prefer larger conspecific females.

Female mate choice is a well studied mechanism of sexual selection that can affect the evolution of male secondary sexual traits. However, males also exhibit selective mate choice in some animals, which can affect the evolution of female phenotypes. We tested for evidence of intraspecific male mate choice in the Rainbow Darter (Percidae: Etheostoma caeruleum). Males of numerous darter species have been shown to prefer conspecific over heterospecific females; however, intraspecific preferences in males have not yet been demonstrated in this genus. This study investigated male preference for indicators of female fecundity, specifically female size. We found that male Rainbow Darters prefer larger females, both in dichotomous choice tests, when access between individuals was prevented, and in unrestricted behavioral tests with full access to females. Notably, however, the dichotomous trials were not repeatable; males only displayed a significant preference for larger females in the first dichotomous trial and in the unrestricted trial. We discuss our results in light of experimental methods and the role of male mate choice in sexual selection.

A Novel Genus of Actinobacterial Tectiviridae.

Streptomyces phages WheeHeim and Forthebois are two novel members of the Tectiviridae family. These phages were isolated on cultures of the plant pathogen Streptomyces scabiei, known for its worldwide economic impact on potato crops. Transmission electron microscopy showed viral particles with double-layered icosahedral capsids, and frequent instances of protruding nanotubes harboring a collar-like structure. Mass-spectrometry confirmed the presence of lipids in the virion, and serial purification of colonies from turbid plaques and immunity testing revealed that both phages are temperate. Streptomycesphages WheeHeim and Forthebois have linear dsDNA chromosomes (18,266 bp and 18,251 bp long, respectively) with the characteristic two-segment architecture of the Tectiviridae. Both genomes encode homologs of the canonical tectiviral proteins (major capsid protein, packaging ATPase and DNA polymerase), as well as PRD1-type virion-associated transglycosylase and membrane DNA delivery proteins. Comparative genomics and phylogenetic analyses firmly establish that these two phages, together with Rhodococcusphage Toil, form a new genus within the Tectiviridae, which we have tentatively named Deltatectivirus. The identification of a cohesive clade of Actinobacteria-infecting tectiviruses with conserved genome structure but with scant sequence similarity to members of other tectiviral genera confirms that the Tectiviridae are an ancient lineage infecting a broad range of bacterial hosts.

Effects of surfactant and gentle agitation on inkjet dispensing of living cells.

Inkjet dispensing is a promising method for patterning cells and biomaterials for tissue engineering applications. In a novel approach, this work uses a biocompatible surfactant to improve the reliability of droplet formation in piezoelectric drop-on-demand inkjet printing of Hep G2 hepatocytes onto hydrogels. During a long printing process, cell aggregation and sedimentation within the inkjet reservoir can lead to inconsistent printing results. In order to improve repeatability, the effects of gentle agitation on cell sedimentation and aggregation within the inkjet reservoir were also investigated. Cell viability and proliferation when printed onto prepared collagen substrates were assessed using live/dead staining and the Alamar Blue metabolic assay. The addition of 0.05% Pluronic as a surfactant did not reduce cell viability, which remained above 95% 2 days after printing. The surfactant improved the reliability of droplet formation. Although gentle stirring of the inkjet reservoir was sufficient to maintain a cell suspension and reduce sedimentation, aggregation within the suspension continued to affect printing performance over a 180 min printing period.