Increasing the impact of vertebrate scientific collections through 3D imaging: The openVertebrate (oVert) Thematic Collections Network.

The impact of preserved museum specimens is transforming and increasing by three-dimensional (3D) imaging that creates high-fidelity online digital specimens. Through examples from the openVertebrate (oVert) Thematic Collections Network, we describe how we created a digitization community dedicated to the shared vision of making 3D data of specimens available and the impact of these data on a broad audience of scientists, students, teachers, artists, and more. High-fidelity digital 3D models allow people from multiple communities to simultaneously access and use scientific specimens. Based on our multiyear, multi-institution project, we identify significant technological and social hurdles that remain for fully realizing the potential impact of digital 3D specimens.

Parasite escape mechanisms drive morphological diversification in avian lice.

Organisms that have repeatedly evolved similar morphologies owing to the same selective pressures provide excellent cases in which to examine specific morphological changes and their relevance to the ecology and evolution of taxa. Hosts of permanent parasites act as an independent evolutionary experiment, as parasites on these hosts are thought to be undergoing similar selective pressures. Parasitic feather lice have repeatedly diversified into convergent ecomorphs in different microhabitats on their avian hosts. We quantified specific morphological characters to determine (i) which traits are associated with each ecomorph, (ii) the quantitative differences between these ecomorphs, and (iii) if there is evidence of displacement among co-occurring lice as might be expected under louse-louse competition on the host. We used nano-computed tomography scan data of 89 specimens, belonging to four repeatedly evolved ecomorphs, to examine their mandibular muscle volume, limb length and three-dimensional head shape data. Here, we find evidence that lice repeatedly evolve similar morphologies as a mechanism to escape host defences, but also diverge into different ecomorphs related to the way they escape these defences. Lice that co-occur with other genera on a host exhibit greater morphological divergence, indicating a potential role of competition in evolutionary divergence.

Comparative analysis of osteoderms across the lizard body.

Osteoderms (ODs) are mineralized tissue embedded within the skin and are particularly common in reptiles. They are generally thought to form a protective layer between the soft tissues of the animal and potential external threats, although other functions have been proposed. The aim of this study was to characterize OD variation across the lizard body. Adults of three lizard species were chosen for this study. After whole body CT scanning of each lizard, single ODs were extracted from 10 different anatomical regions, CT scanned, and characterized using sectioning and nanoindentation. Morphological analysis and material characterization revealed considerable diversity in OD structure across the species investigated. The scincid Tiliqua gigas was the only studied species in which ODs had a similar external morphology across the head and body. Greater osteoderm diversity was found in the gerrhosaurid Broadleysaurus major and the scincid Tribolonotus novaeguineae. Dense capping tissue, like that reported for Heloderma, was found in only one of the three species examined, B. major. Osteoderm structure can be surprisingly complex and variable, both among related taxa, and across the body of individual animals. This raises many questions about OD function but also about the genetic and developmental factors controlling OD shape.

The first full body diffusible iodine-based contrast-enhanced computed tomography dataset and teaching materials for a member of the Testudines.

Diffusible iodine-based contrast-enhanced Computed Tomography (diceCT) is now a widely used technique for imaging metazoan soft anatomy. Turtles present a particular challenge for anatomists; gross dissection is inherently destructive and irreversible, whereas their near complete shell of bony plates, covered with keratinous scutes, presents a barrier for iodine diffusion and significantly increases contrast-enhanced CT preparation time. Consequently, a complete dataset visualizing the internal soft anatomy of turtles at high resolution and in three dimensions has not yet been successfully achieved. Here we outline a novel method that augments traditional diceCT preparation with an iodine injection technique to acquire the first full body contrast-enhanced dataset for the Testudines. We show this approach to be an effective method of staining the soft tissues inside the shell. The resulting datasets were processed to produce anatomical 3D models that can be used in teaching and research. As diceCT becomes a widely employed method for nondestructively documenting the internal soft anatomy of alcohol preserved museum specimens, we hope that methods applicable to the more challenging of these, such as turtles, will contribute toward the growing stock of digital anatomy in online repositories.

Anatomy of the female reproductive tract organs of the brown anole (Anolis sagrei).

Female reproduction in squamate reptiles (lizards and snakes) is highly diverse and mode of reproduction, clutch size, and reproductive tract morphology all vary widely across this group of ~11,000 species. Recently, CRISPR genome editing techniques that require manipulation of the female reproductive anatomy have been developed in this group, making a more complete understanding of this anatomy essential. We describe the adult female reproductive anatomy of the model reptile the brown anole (Anolis sagrei). We show that the brown anole female reproductive tract has three distinct anterior-to-posterior regions, the infundibulum, the glandular uterus, and the nonglandular uterus. The infundibulum has a highly ciliated epithelial lip, a region where the epithelium is inverted so that cilia are present on the inside and outside of the tube. The glandular uterus has epithelial ducts that are patent with a lumen as well as acinar structures with a lumen. The nonglandular uterus has a heterogeneous morphology from anterior to posterior, with a highly folded, ciliated epithelium transitioning to a stratified squamous epithelium. This transition is accompanied by a loss of keratin-8 expression and together, these changes are similar to the morphological and gene expression changes that occur in the mammalian cervix. We recommend that description of the nonglandular uterus include the regional sub-specification of a "cervix" and "vagina" as this terminology change more accurately describes the morphology. Our data extend histological studies of reproductive organ morphology in reptiles and expand our understanding of the variation in reproductive system anatomy across squamates and vertebrates.

The seven-fold rise in incidence of Stevens-Johnson syndrome & toxic epidermal necrolysis: Associations with COVID-19 and the vaccine.

Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) is a rare, potentially life threatening mucocutaneous hypersensitivity reaction resulting in desquamation of the skin and mucosa. These patients are managed on burns units due to the widespread desquamation. We report the largest case series of participants developing SJS/TEN in the setting of recent COVID infection or vaccination. We found a seven-fold increase in SJS/TEN since the COVID pandemic. This increase correlates with an increase in COVID infections and vaccination rates. We explore the immunopathological relationships between COVID and SJS/TEN and propose theories for possible associations.

3D pollination biology using micro-computed tomography and geometric morphometrics in Theobroma cacao.

Premise: Imaging technologies that capture three-dimensional (3D) variation in floral morphology at micro- and nano-resolutions are increasingly accessible. In herkogamous flowers, such as those of Theobroma cacao, structural barriers between anthers and stigmas represent bottlenecks that restrict pollinator size and access to reproductive organs. To study the unresolved pollination biology of cacao, we present a novel application of micro-computed tomography (micro-CT) using floral dimensions to quantify pollinator functional size limits. Methods: We generated micro-CT data sets from field-collected flowers and museum specimens of potential pollinators. To compare floral variation, we used 3D Slicer to place landmarks on the surface models and performed a geometric morphometric (GMM) analysis using geomorph R. We identified the petal side door (an opening between the petal hoods and filament) as the main bottleneck for pollinator access. We compared its mean dimensions with proposed pollinators to identify viable candidates. Results: We identified three levels of likelihood for putative pollinators based on the number of morphological (body) dimensions that fit through the petal side door. We also found floral reward microstructures whose presence and location were previously unclear. Discussion: Using micro-CT and GMM to study the 3D pollination biology of cacao provides new evidence for predicting unknown pollinators. Incorporating geometry and floral rewards will strengthen plant-pollinator trait matching models for cacao and other species.

Uncovering key clinical trial features influencing recruitment.

Background: Randomized clinical trials (RCT) are the foundation for medical advances, but participant recruitment remains a persistent barrier to their success. This retrospective data analysis aims to (1) identify clinical trial features associated with successful participant recruitment measured by accrual percentage and (2) compare the characteristics of the RCTs by assessing the most and least successful recruitment, which are indicated by varying thresholds of accrual percentage such as ≥ 90% vs ≤ 10%, ≥ 80% vs ≤ 20%, and ≥ 70% vs ≤ 30%. Methods: Data from the internal research registry at Columbia University Irving Medical Center and Aggregated Analysis of ClinicalTrials.gov were collected for 393 randomized interventional treatment studies closed to further enrollment. We compared two regularized linear regression and six tree-based machine learning models for accrual percentage (i.e., reported accrual to date divided by the target accrual) prediction. The outperforming model and Tree SHapley Additive exPlanations were used for feature importance analysis for participant recruitment. The identified features were compared between the two subgroups. Results: CatBoost regressor outperformed the others. Key features positively associated with recruitment success, as measured by accrual percentage, include government funding and compensation. Meanwhile, cancer research and non-conventional recruitment methods (e.g., websites) are negatively associated with recruitment success. Statistically significant subgroup differences (corrected p-value < .05) were found in 15 of the top 30 most important features. Conclusion: This multi-source retrospective study highlighted key features influencing RCT participant recruitment, offering actionable steps for improvement, including flexible recruitment infrastructure and appropriate participant compensation.

Reed bamboos drive skull shape evolution in bush frogs of the Western Ghats, Peninsular India.

Reed bamboo is a major ecological and economic resource for many animals, including humans. Nonetheless, the influence of this plant's evolutionary role on the morphology of animal species remains unexplored. Here, we investigated the significance of bamboo habitats as ecological opportunities in shaping the skull morphology of bush frogs (Raorchestes) from the Western Ghats, Peninsular India. We applied a three-dimensional (3D) geometric morphometric approach to capture the skull shape of 55 species of bush frogs. We visualized the skull shape variables in phylomorphospace with principal component analysis and performed phylogenetic generalized least-squares analysis to assess the impact of cranial size (evolutionary allometry) and habitat (bamboo or non-bamboo) on cranial shape. We quantified the morphological disparity between bamboo and non-bamboo bush frogs' skull shape, and employed RRphylo, a phylogenetic ridge regression method, to access the evolutionary rate and rate shifts of skull shape change. The phylomorphospace delineated bamboo and non-bamboo bush frogs. While cranial shape exhibited a significant but smaller association with size, its association with habitat type was non-significant. We detected, however, significant differences in skull shape between the two frog groups, with bamboo frogs showing higher morphological disparity and a remarkable shift in the evolutionary rate of skull shape diversification. These findings underscore the role of reed bamboo in the evolution of skull shape in the radiation of frogs, endemic to the Western Ghats. We demonstrate that the association between the members of two distinct endemic clades (bamboo reeds and bamboo frogs) is the outcome of a deep-time ecological opportunity that dates back to the Miocene.

Mammography Screening Outreach Through Non-Primary Care-Based Services.

OBJECTIVE: To estimate the proportion of patients visiting urgent care centers or emergency departments or being hospitalized who were not up to date with recommended mammography screening to assess the potential impact of non-primary care-based cancer screening interventions. METHODS: Adult participants from the 2019 National Health Interview Survey were included. Among participants not up to date with breast cancer screening guidelines based on ACR recommendations, the proportion of patients reporting an urgent care, emergency department visit, or hospitalization within the last year was estimated accounting for complex survey sampling design features. Multiple variable logistic regression analyses were then conducted to evaluate the association between sociodemographic characteristics and mammography screening adherence. RESULTS: The study included 9,139 women between the ages of 40 and 74 years without history of breast cancer. Of these respondents, 44.9% did not report mammography screening within the last year. Among participants who did not report mammography screening, 29.2% reported visiting an urgent care center, 21.8% reported visiting an emergency room, and 9.6% reported being hospitalized within the last year. The majority of patients receiving non-primary care-based services, who were not up to date with mammography screening, were from historically underserved groups including Black and Hispanic patients. CONCLUSION: Nearly 10% to 30% of participants who have not obtained recommended breast cancer screening have visited non-primary care-based services including urgent care centers or emergency rooms or have been hospitalized within the last year.

Osteoderms in a mammal the spiny mouse Acomys and the independent evolution of dermal armor.

Osteoderms are bony plates found in the skin of vertebrates, mostly commonly in reptiles where they have evolved independently multiple times, suggesting the presence of a gene regulatory network that is readily activated and inactivated. They are absent in birds and mammals except for the armadillo. However, we have discovered that in one subfamily of rodents, the Deomyinae, there are osteoderms in the skin of their tails. Osteoderm development begins in the proximal tail skin and is complete 6 weeks after birth. RNA sequencing has identified the gene networks involved in their differentiation. There is a widespread down-regulation of keratin genes and an up-regulation of osteoblast genes and a finely balanced expression of signaling pathways as the osteoderms differentiate. Future comparisons with reptilian osteoderms may allow us to understand how these structures have evolved and why they are so rare in mammals.

Understanding Neural Factors in Burn-related Pruritus and Neuropathic Pain.

Post-burn pruritus and neuropathic pain significantly affect the quality of life of affected individuals in several domains including psychosocial well-being, sleep and general impairment in activities of daily living. Whilst neural mediators involved in itch in the non-burns setting have been well investigated, there remains a lacuna of literature examining the pathophysiological and histological changes unique to burn-related pruritus and neuropathic pain. The aim of our study was to conduct a scoping review into the neural factors that contribute to burn-related pruritus and neuropathic pain. A scoping review was conducted to provide an overview of the available evidence. The PubMed, EMBASE and Medline databases were searched for publications. Data regarding neural mediators implicated, population demographics, total body surface area (TBSA) affected and sex was extracted. In total, 11 studies were included in this review with a total of 881 patients. The most frequently investigated neurotransmitter was the Substance P (SP) neuropeptide which appeared in 36% of studies (n = 4), followed by calcitonin gene-related peptide (CGRP) in 27% of studies (n = 3). Post-burn pruritus and neuropathic pain are symptomatic experiences that are predicated upon a heterogeneous group of underlying mechanisms. What is clear from the literature, however, is that itch and pain may occur secondary to the influence of both neuropeptides, such as SP, and other neural mediators including Transient receptor protein channels. Of the articles included for review, they were characterized by small sample sizes and large differences in statistical methodology and reporting.

Predicting strength outcomes for upper limb nerve transfer surgery in tetraplegia.

We report a retrospective study of 112 nerve transfers in 39 participants to investigate predictors of strength outcomes after nerve transfer surgery for upper limb reanimation in tetraplegia. We measured clinical and pre- and intraoperative neurophysiological assessment variables and compared them with strength outcomes 2 years after nerve transfer surgery. We found statistically significant improvement in Medical Research Council strength grades after nerve transfer surgery with lower cervical spine injuries (between one and two grades), lower donor nerve stimulation thresholds (half of a grade), greater motor evoked potential activity in recipient nerves (half of a grade) and greater muscle responses to intraoperative stimulation of donor (half of a grade) and recipient nerves (half of a grade).Level of evidence: III.

Semicircular canal size constrains vestibular function in miniaturized frogs.

Miniaturization has evolved repeatedly in frogs in the moist leaf litter environments of rainforests worldwide. Miniaturized frogs are among the world's smallest vertebrates and exhibit an array of enigmatic features. One area where miniaturization has predictable consequences is the vestibular system, which acts as a gyroscope, providing sensory information about movement and orientation. We investigated the vestibular system of pumpkin toadlets, Brachycephalus (Anura: Brachycephalidae), a clade of miniaturized frogs from Brazil. The semicircular canals of miniaturized frogs are the smallest recorded for adult vertebrates, resulting in low sensitivity to angular acceleration due to insufficient displacement of endolymph. This translates into a lack of postural control during jumping in Brachycephalus and represents a physical constraint resulting from Poiseuille's law, which governs movement of fluids within tubes.

A new Early Cretaceous lizard in Myanmar amber with exceptionally preserved integument.

We here report on a well-preserved juvenile lizard specimen in Albian amber (ca. 110 mya) from the Hkamti site (Myanmar). This new taxon is represented by an articulated skull and the anterior portion of the trunk, including the pectoral girdle and forelimbs. The scleral ossicles and eyelid are also visible, and the specimen exhibits pristine detail of the integument (of both head and body). In a combined molecular and morphological analysis, it was consistently recovered as a scincoid lizard (Scinciformata), as sister to Tepexisaurus + Xantusiidae. However, the phylogenetic position of the new taxon should be interpreted with caution as the holotype is an immature individual. We explored the possibility of miscoding ontogenetically variable characters by running alternative analyses in which these characters were scored as missing data for our taxon. With the exception of one tree, in which it was sister to Amphisbaenia, the specimen was recovered as a Pan-xantusiid. Moreover, we cannot rule out the possibility that it represents a separate lineage of uncertain phylogenetic position, as it is the case for many Jurassic and Cretaceous taxa. Nonetheless, this fossil offers a rare opportunity to glimpse the external appearance of one group of lizards during the Early Cretaceous.

Re-evaluating the morphological evidence for the re-evolution of lost mandibular teeth in frogs.

Dollo's law of irreversibility states that once a complex structure is lost, it cannot be regained in the same form. Several putative exceptions to Dollo's law have been identified using phylogenetic comparative methods, but the anatomy and development of these traits are often poorly understood. Gastrotheca guentheri is renowned as the only frog with teeth on the lower jaw. Mandibular teeth were lost in the ancestor of frogs more than 200 million years ago and subsequently regained in G. guentheri. Little is known about the teeth in this species despite being a frequent example of trait "re-evolution," leaving open the possibility that it may have mandibular pseudoteeth. We assessed the dental anatomy of G. guentheri using micro-computed tomography and histology and confirmed the longstanding assumption that true mandibular teeth are present. Remarkably, the mandibular teeth of G. guentheri are nearly identical in gross morphology and development to upper jaw teeth in closely related species. The developmental genetics of tooth formation are unknown in this possibly extinct species. Our results suggest that an ancestral odontogenic pathway has been conserved but suppressed in the lower jaw since the origin of frogs, providing a possible mechanism underlying the re-evolution of lost mandibular teeth.

Unveiling the elusive: X-rays bring scolecophidian snakes out of the dark.

Scolecophidian snakes have long posed challenges for scholars interested in elucidating their anatomy. The importance, and relative paucity, of high-quality anatomical data pertaining to scolecophidians was brought into sharp focus in the late 20th century as part of a controversy over the phylogeny and ecological origin of snakes. The basal position of scolecophidians in the phylogeny of snakes makes their anatomy, behavior, ecology, and evolution especially important for such considerations. The depauperate fossil record for the group meant that advances in understanding their evolutionary history were necessarily tied to biogeographic distributions and anatomical interpretations of extant taxa. Osteological data, especially data pertaining to the skull and mandible, assumed a dominant role in shaping historical and modern perspectives of the evolution of scolecophidians. Traditional approaches to the exploration of the anatomy of these snakes relied heavily upon serial-sectioned specimens and cleared-and-stained specimens. The application of X-ray computed tomography (CT) to the study of scolecophidians revolutionized our understanding of the osteology of the group, and now, via diffusible iodine-based contrast-enhanced computed tomography (diceCT), is yielding data sets on internal soft anatomical features as well. CT data sets replicate many aspects of traditional anatomical preparations, are readily shared with a global community of scholars, and now are available for unique holotype and other rare specimens. The increasing prevalence and relevance of CT data sets is a strong incentive for the establishment and maintenance of permanent repositories for digital data.

Underground Down Under: Skull anatomy of the southern blind snake Anilios australis Gray, 1845 (Typhlopidae: Serpentes: Squamata).

The cranial anatomy of blindsnakes has been markedly understudied, with the small size and relative rarity of encountering these subterranean reptiles being significant limiting factors. In this article, we re-visit the skull anatomy of the Australian southern blind snake Anilios australis Gray, 1845 using microCT data, and produce the first complete atlas for the cranial anatomy of a representative of this speciose typhlopid genus. The skull is formed by 18 paired and four unpaired elements. We here produce a bone-by-bone description of each element as well as an inner ear endocast for each of two specimens differing in skull size. This approach has revealed the presence of a highly perforated dorsal plate on the septomaxilla-a structure convergent with the cribriform plate of the mammalian ethmoid bone-and a feature previously unknown for typhlopid snakes. This detailed anatomical study will facilitate ongoing taxonomic and systematic studies in the genus Anilios as well as provide comparative data for future studies on blindsnake anatomy more broadly.