Genome assembly of the dyeing poison frog provides insights into the dynamics of transposable element and genome-size evolution.

Genome size varies greatly across the tree of life and transposable elements are an important contributor to this variation. Among vertebrates, amphibians display the greatest variation in genome size, making them ideal models to explore the causes and consequences of genome size variation. However, high-quality genome assemblies for amphibians have, until recently, been rare. Here, we generate a high-quality genome assembly for the dyeing poison frog, Dendrobates tinctorius. We compare this assembly to publicly available frog genomes and find evidence for both large-scale conserved synteny and widespread rearrangements between frog lineages. Comparing conserved orthologs annotated in these genomes revealed a strong correlation between genome size and gene size. To explore the cause of gene-size variation, we quantified the location of transposable elements relative to gene features and find that the accumulation of transposable elements in introns has played an important role in the evolution of gene size in D. tinctorius, while estimates of insertion times suggest that many insertion events are recent and species-specific. Finally, we carry out population-scale mobile-element sequencing and show that the diversity and abundance of transposable elements in poison frog genomes can complicate genotyping from repetitive element sequence anchors. Our results show that transposable elements have clearly played an important role in the evolution of large genome size in D. tinctorius. Future studies are needed to fully understand the dynamics of transposable element evolution and to optimise primer or bait design for cost-effective population-level genotyping in species with large, repetitive genomes.

What is the rate of definitive stoma after subtotal colectomy for inflammatory bowel disease? A nationwide study of 1860 patients.

AIM: Some patients with inflammatory bowel disease (IBD) require subtotal colectomy (STC) with ileostomy. The recent literature reports a significant number of patients who do not undergo subsequent surgery and are resigned to living with a definitive stoma. The aim of this work was to analyse the rate of definitive stoma and the cumulative incidence of secondary reconstructive surgery after STC for IBD in a large national cohort study. METHOD: A national retrospective study (2013-2021) was conducted on prospectively collected data from the French Medical Information System Database (PMSI). All patients undergoing STC in France were included. The association between definitive stoma and potential risk factors was studied using univariate and multivariate analyses. RESULTS: A total of 1860 patients were included (age 45 ± 9 years; median follow-up 30 months). Of these, 77% (n = 1442) presented with ulcerative colitis. Mortality and morbidity at 90 days after STC were 5% (n = 100) and 47% (n = 868), respectively. Reconstructive surgery was identified in 1255 patients (67%) at a mean interval of 7 months from STC. Seveny-four per cent (n = 932) underwent a completion proctectomy with ileal pouch anal anastomosis and 26% (n = 323) an ileorectal anastomosis. Six hundred and five (33%) patients with a definitive stoma had an abdominoperineal resection (n = 114; 19%) or did not have any further surgical procedure (n = 491; 81%). Independent risk factors for definitive stoma identified in multivariate analysis were older age, Crohn's disease, colorectal neoplasia, postoperative complication after STC, laparotomy and a low-volume hospital. CONCLUSION: We found that 33% of patients undergoing STC with ileostomy for IBD had definitive stoma. Modifiable risk factors for definitive stoma were laparotomy and a low-volume hospital.

Rectovaginal Fistula: What is the Role of Martius Flap and Gracilis Muscle Interposition in the Therapeutic Strategy?

BACKGROUND: While numerous treatments exist for management of rectovaginal fistula, none has demonstrated its superiority. The role of diverting stoma remains controversial. Few series include Martius flap in the armamentarium. OBJECTIVE: Determine the role of gracilis muscle interposition and Martius flap in the surgical management of rectovaginal fistula. DESIGN: Retrospective cohort study of a pooled prospectively maintained database from 3 centers. SETTINGS/PATIENTS: All consecutive eligible patients with rectovaginal fistula undergoing Martius flap and gracilis muscle interposition were included from 2001 to 2022. MAIN OUTCOMES: Success was defined by absence of stoma and rectovaginal fistula. RESULTS: Sixty-two patients were included with 55 Martius flap and 24 gracilis muscle interposition performed after failures of 164 initial procedures. Total length of stay was longer for gracilis muscle interposition by 2 days (p = 0.01) without a significant difference in severe morbidity (20% vs. 12%, p = 0.53). 27% of Martius flap were performed without stoma, without impact on overall morbidity (p = 0.763). Per-patient immediate success rates were not significantly different between groups (35% vs. 31%, p = 1.0). Success of gracilis muscle interposition after failure of Martius flap was not significantly different from an initial gracilis muscle interposition (p = 1.0). The immediate success rate rose to 49.4% (49% vs. 50%, p = 1.0) after simple perineal procedures. After a median follow-up of 23 months, there was no significant difference detected in success rate between the two procedures (69% vs. 69%, p = 1.0). Smoking was the only negative predictive factor (p = 0.02). LIMITATIONS: By its retrospective nature, this study is limited in its comparison. CONCLUSION: This novel comparison between Martius flap and gracilis muscle interposition suggests that Martius flap presents several advantages, including shorter length of stay, similar morbidity, and success. Proximal diversion via a stoma for Martius flap does not appear mandatory. Gracilis muscle interposition could be reserved as a salvage procedure after Martius flap failure. See Video Abstract.

Pavement ant extract is a chemotaxis repellent for C. elegans.

Ant behavior relies on a collection of natural products, from following trail pheromones during foraging to warding off potential predators. How nervous systems sense these compounds to initiate a behavioral response remains unclear. Here, we used Caenorhabditis elegans chemotaxis assays to investigate how ant compounds are detected by heterospecific nervous systems. We found that C. elegans avoid extracts of the pavement ant ( Tetramorium immigrans ) and either osm-9 or tax-4 ion channels are required for this response. These experiments were conducted in an undergraduate laboratory course, demonstrating that new insights into interspecies interactions can be generated through genuine research experiences in a classroom setting.

Influence of neoadjuvant treatment strategy on perioperative outcomes in locally advanced rectal cancer.

AIM: Neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer facilitates tumour downstaging and complete pathological response (pCR). The goal of neoadjuvant systemic chemotherapy (total neoadjuvant chemotherapy, TNT) is to further improve local and systemic control. While some patients forgo surgery, total mesorectal excision (TME) remains the standard of care. While TNT appears to be noninferior to nCRT with respect to short-term oncological outcomes few data exist on perioperative outcomes. Perioperative morbidity including anastomotic leaks is associated with a negative effect on oncological outcomes, probably due to a delay in proceeding to adjuvant therapy. Thus, we aimed to compare conversion rates, rates of sphincter-preserving surgery and anastomosis formation rates in patients undergoing rectal resection after either TNT or standard nCRT. METHODS: An institutional colorectal oncology database was searched from January 2018 to July 2023. Inclusion criteria comprised patients with histologically confirmed rectal cancer who had undergone neoadjuvant therapy and TME. Exclusion criteria comprised patients with a noncolorectal primary, those operated on emergently or who had local excision only. Outcomes evaluated included rates of conversion to open, sphincter-preserving surgery, anastomosis formation and anastomotic leak. RESULTS: A total of 119 patients were eligible for inclusion (60 with standard nCRT, 59 with TNT). There were no differences in rates of sphincter preservation or primary anastomosis formation between the groups. However, a significant increase in conversion to open (p = 0.03) and anastomotic leak (p = 0.03) was observed in the TNT cohort. CONCLUSION: In this series TNT appears to be associated with higher rates of conversion to open surgery and higher anastomotic leak rates. While larger studies will be required to confirm these findings, these factors should be considered alongside oncological benefits when selecting treatment strategies.

Heterogeneous lineage-specific arginine deiminase expression within dental microbiome species.

Arginine catabolism by the bacterial arginine deiminase system (ADS) has anticariogenic properties through the production of ammonia, which modulates the pH of the oral environment. Given the potential protective capacity of the ADS pathway, the exploitation of ADS-competent oral microbes through pre- or probiotic applications is a promising therapeutic target to prevent tooth decay. To date, most investigations of the ADS in the oral cavity and its relation to caries have focused on indirect measures of activity or on specific bacterial groups, yet the pervasiveness and rate of expression of the ADS operon in diverse mixed microbial communities in oral health and disease remain an open question. Here, we use a multivariate approach, combining ultra-deep metatranscriptomic sequencing with paired metataxonomic and in vitro citrulline quantification to characterize the microbial community and ADS operon expression in healthy and late-stage cavitated teeth. While ADS activity is higher in healthy teeth, we identify multiple bacterial lineages with upregulated ADS activity on cavitated teeth that are distinct from those found on healthy teeth using both reference-based mapping and de novo assembly methods. Our dual metataxonomic and metatranscriptomic approach demonstrates the importance of species abundance for gene expression data interpretation and that patterns of differential expression can be skewed by low-abundance groups. Finally, we identify several potential candidate probiotic bacterial lineages within species that may be useful therapeutic targets for the prevention of tooth decay and propose that the development of a strain-specific, mixed-microbial probiotic may be a beneficial approach given the heterogeneity of taxa identified here across health groups. IMPORTANCE: Tooth decay is the most common preventable chronic disease, affecting more than two billion people globally. The development of caries on teeth is primarily a consequence of acid production by cariogenic bacteria that inhabit the plaque microbiome. Other bacterial strains in the oral cavity may suppress or prevent tooth decay by producing ammonia as a byproduct of the arginine deiminase metabolic pathway, increasing the pH of the plaque biofilm. While the benefits of arginine metabolism on oral health have been extensively documented in specific bacterial groups, the prevalence and consistency of arginine deiminase system (ADS) activity among oral bacteria in a community context remain an open question. In the current study, we use a multi-omics approach to document the pervasiveness of the expression of the ADS operon in both health and disease to better understand the conditions in which ADS activity may prevent tooth decay.

A toxic environment selects for specialist microbiome in poison frogs.

Shifts in microbiome community composition can have large effects on host health. It is therefore important to understand how perturbations, like those caused by the introduction of exogenous chemicals, modulate microbiome community composition. In poison frogs within the family Dendrobatidae, the skin microbiome is exposed to the alkaloids that the frogs sequester from their diet and use for defense. Given the demonstrated antimicrobial effects of these poison frog alkaloids, these compounds may be structuring the skin microbial community. To test this, we first characterized microbial communities from chemically defended and closely related non-defended frogs from Ecuador. Then we conducted a laboratory experiment to monitor the effect of the alkaloid decahydroquinoline (DHQ) on the microbiome of a single frog species. In both the field and lab experiments, we found that alkaloid-exposed microbiomes are more species rich and phylogenetically diverse, with an increase in rare taxa. To better understand the strain-specific behavior in response to alkaloids, we cultured microbial strains from poison frog skin and found the majority of strains exhibited either enhanced growth or were not impacted by the addition of DHQ. Additionally, stable isotope tracing coupled to nanoSIMS suggests that some of these strains are able to metabolize DHQ. Taken together, these data suggest that poison frog chemical defenses open new niches for skin-associated microbes with specific adaptations, including the likely metabolism of alkaloids, that enable their survival in this toxic environment. This work helps expand our understanding of how exposure to exogenous compounds like alkaloids can impact host microbiomes.

Selection on Visual Opsin Genes in Diurnal Neotropical Frogs and Loss of the SWS2 Opsin in Poison Frogs.

Amphibians are ideal for studying visual system evolution because their biphasic (aquatic and terrestrial) life history and ecological diversity expose them to a broad range of visual conditions. Here, we evaluate signatures of selection on visual opsin genes across Neotropical anurans and focus on three diurnal clades that are well-known for the concurrence of conspicuous colors and chemical defense (i.e., aposematism): poison frogs (Dendrobatidae), Harlequin toads (Bufonidae: Atelopus), and pumpkin toadlets (Brachycephalidae: Brachycephalus). We found evidence of positive selection on 44 amino acid sites in LWS, SWS1, SWS2, and RH1 opsin genes, of which one in LWS and two in RH1 have been previously identified as spectral tuning sites in other vertebrates. Given that anurans have mostly nocturnal habits, the patterns of selection revealed new sites that might be important in spectral tuning for frogs, potentially for adaptation to diurnal habits and for color-based intraspecific communication. Furthermore, we provide evidence that SWS2, normally expressed in rod cells in frogs and some salamanders, has likely been lost in the ancestor of Dendrobatidae, suggesting that under low-light levels, dendrobatids have inferior wavelength discrimination compared to other frogs. This loss might follow the origin of diurnal activity in dendrobatids and could have implications for their behavior. Our analyses show that assessments of opsin diversification in across taxa could expand our understanding of the role of sensory system evolution in ecological adaptation.

Supragingival mycobiome of HIV-exposed-but-uninfected children reflects a stronger correlation with caries-free-associated taxa compared to HIV-infected or uninfected children.

IMPORTANCE: Globally, caries is among the most frequent chronic childhood disease, and the fungal component of the microbial community responsible is poorly studied despite evidence that fungi contribute to increased acid production exacerbating enamel demineralization. HIV infection is another global health crisis. Perinatal HIV exposure with infection are caries risk factors; however, the caries experience in the context of perinatal HIV exposure without infection is less clear. Using high-throughput amplicon sequencing, we find taxonomic differences that become pronounced during late-stage caries. Notably, we show a stronger correlation with health-associated taxa for HIV-exposed-but-uninfected children when compared to unexposed and uninfected children. This aligns with a lower incidence of caries in primary teeth at age 6 or less for exposed yet uninfected children. Ultimately, these findings could contribute to improved risk assessment, intervention, and prevention strategies such as biofilm disruption and the informed design of pro-, pre-, and synbiotic oral therapies.

Tissue-specific in vivo transformation of plasmid DNA in Neotropical tadpoles using electroporation.

Electroporation is an increasingly common technique used for exogenous gene expression in live animals, but protocols are largely limited to traditional laboratory organisms. The goal of this protocol is to test in vivo electroporation techniques in a diverse array of tadpole species. We explore electroporation efficiency in tissue-specific cells of five species from across three families of tropical frogs: poison frogs (Dendrobatidae), cryptic forest/poison frogs (Aromobatidae), and glassfrogs (Centrolenidae). These species are well known for their diverse social behaviors and intriguing physiologies that coordinate chemical defenses, aposematism, and/or tissue transparency. Specifically, we examine the effects of electrical pulse and injection parameters on species- and tissue-specific transfection of plasmid DNA in tadpoles. After electroporation of a plasmid encoding green fluorescent protein (GFP), we found strong GFP fluorescence within brain and muscle cells that increased with the amount of DNA injected and electrical pulse number. We discuss species-related challenges, troubleshooting, and outline ideas for improvement. Extending in vivo electroporation to non-model amphibian species could provide new opportunities for exploring topics in genetics, behavior, and organismal biology.

Impact of HIV on the Oral Microbiome of Children Living in Sub-Saharan Africa, Determined by Using an rpoC Gene Fragment Metataxonomic Approach.

Children living with HIV have a higher prevalence of oral diseases, including caries, but the mechanisms underlying this higher prevalence are not well understood. Here, we test the hypothesis that HIV infection is associated with a more cariogenic oral microbiome, characterized by an increase in bacteria involved in the pathogenesis of caries. We present data generated from supragingival plaques collected from 484 children representing three exposure groups: (i) children living with HIV (HI), (ii) children who were perinatally exposed but uninfected (HEU), and (iii) unexposed and therefore uninfected children (HUU). We found that the microbiome of HI children is distinct from those of HEU and HUU children and that this distinction is more pronounced in diseased teeth than healthy teeth, suggesting that the impact of HIV is more severe as caries progresses. Moreover, we report both an increase in bacterial diversity and a decrease in community similarity in our older HI cohort compared to our younger HI cohort, which may in part be a prolonged effect of HIV and/or its treatment. Finally, while Streptococcus mutans is often a dominant species in late-stage caries, it tended to be found at lower frequency in our HI cohort than in other groups. Our results highlight the taxonomic diversity of the supragingival plaque microbiome and suggest that broad and increasingly individualistic ecological shifts are responsible for the pathogenesis of caries in children living with HIV, coupled with a diverse and possibly severe impact on known cariogenic taxa that potentially exacerbates caries. IMPORTANCE Since its recognition as a global epidemic in the early 1980s, approximately 84.2 million people have been diagnosed with HIV and 40.1 million people have died from AIDS-related illnesses. The development and increased global availability of antiretroviral treatment (ART) regimens have dramatically reduced the mortality rate of HIV and AIDS, yet approximately 1.5 million new infections were reported in 2021, 51% of which are in sub-Saharan Africa. People living with HIV have a higher prevalence of caries and other chronic oral diseases, the mechanisms of which are not well understood. Here, we used a novel genetic approach to characterize the supragingival plaque microbiome of children living with HIV and compared it to the microbiomes of uninfected and perinatally exposed children to better understand the role of oral bacteria in the etiology of tooth decay in the context of HIV exposure and infection.

Activity of FoxP2-positive neurons correlate with tadpole begging behavior.

Motor function is a critical aspect of social signaling in a wide range of taxa. The transcription factor FoxP2 is well studied in the context of vocal communication in humans, mice, and songbirds, but its role in regulating social signaling in other vertebrate taxa is unclear. We examined the distribution and activity of FoxP2-positive neurons in tadpoles of the mimetic poison frog (Ranitomeya imitator). In this species, tadpoles are reared in isolated plant nurseries and are aggressive to other tadpoles. Mothers provide unfertilized egg meals to tadpoles that perform a begging display by vigorously vibrating back and forth. We found that FoxP2 is widely distributed in the tadpole brain and parallels the brain distribution in mammals, birds, and fishes. We then tested the hypothesis that FoxP2-positive neurons would have differential activity levels in begging or aggression contexts compared to non-social controls. We found that FoxP2-positive neurons showed increased activation in the striatum and cerebellum only during begging. Overall, this work suggests a generalizable role for FoxP2 in social signaling across terrestrial vertebrates.

Home security cameras as a tool for behavior observations and science equity.

Reliably capturing transient animal behavior in the field and laboratory remains a logistical and financial challenge, especially for small ectotherms. Here, we present a camera system that is affordable, accessible, and suitable to monitor small, cold-blooded animals historically overlooked by commercial camera traps, such as small amphibians. The system is weather-resistant, can operate offline or online, and allows collection of time-sensitive behavioral data in laboratory and field conditions with continuous data storage for up to four weeks. The lightweight camera can also utilize phone notifications over Wi-Fi so that observers can be alerted when animals enter a space of interest, enabling sample collection at proper time periods. We present our findings, both technological and scientific, in an effort to elevate tools that enable researchers to maximize use of their research budgets. We discuss the relative affordability of our system for researchers in South America, which is home to the largest population of ectotherm diversity.

Argentine ant extract induces an osm-9 dependent chemotaxis response in C. elegans.

Many ant species are equipped with chemical defenses, although how these compounds impact nervous system function is unclear. Here, we examined the utility of Caenorhabditis elegans chemotaxis assays for investigating how ant chemical defense compounds are detected by heterospecific nervous systems. We found that C. elegans respond to extracts from the invasive Argentine Ant ( Linepithema humile ) and the osm-9 ion channel is required for this response. Divergent strains varied in their response to L. humile extracts, suggesting genetic variation underlying chemotactic responses. These experiments were conducted by an undergraduate laboratory course, highlighting how C. elegans chemotaxis assays in a classroom setting can provide genuine research experiences and reveal new insights into interspecies interactions.

Ambulatory appendectomy for acute appendicitis: Can we treat all the patients? A prospective study of 451 consecutive ambulatory appendectomies out of nearly 2,000 procedures.

BACKGROUND: Acute appendicitis represents the leading cause of acute gastrointestinal disorders, but only a small series regarding ambulatory appendectomies are available. The aim of this study was to report the results of ambulatory (day-case) appendectomy for acute appendicitis in a large consecutive cohort and to improve selection criteria in order to extend the indications. METHODS: All appendectomy procedures for acute appendicitis (March 2013 to June 2020) were included retrospectively. Criteria to select patients eligible for ambulatory appendectomy were based on our clinico-radiological St-Antoine's score ≥4. RESULTS: In total, 1,730 consecutive patients had an appendectomy for acute appendicitis: 1,279 (74%) in conventional settings and 451 (26%) in ambulatory settings. In the conventional group, 360 (28%) patients had surgery deferred to the next morning, whereas in the ambulatory group, 309 patients (70%) were readmitted the next morning (P < .0001). In the ambulatory group, 376 (83%) patients satisfied the criteria (score ≥4), and 90.9% were discharged on postoperative day 0. Rates of unplanned consultation and readmission were not significantly different (5.1% vs 6.6% P = .243). Multivariate analysis of the entire cohort confirmed absence of radiological perforation as highly predictive of early discharge (odds ratio = 6.073). In our cohort, these patients had an early discharge rate of 86.4% compared to 90.2% in those with a St-Antoine's score ≥4. Considering only radiological evidence of perforation as a selection criterion for ambulatory appendectomy, 581 more patients would be eligible for ambulatory surgery (+60%). CONCLUSION: Ambulatory surgery for acute appendicitis based on St-Antoine's score is safe. We propose to extend the indication for ambulatory management to all patients without radiological evidence of perforation.

Albino Xenopus laevis tadpoles prefer dark environments compared to wild type.

Tadpoles display preferences for different environments but the sensory modalities that govern these choices are not well understood. Here, we examined light preferences and associated sensory mechanisms of albino and wild-type Xenopus laevis tadpoles. We found that albino tadpoles spent more time in darker environments compared to the wild type, although they showed no differences in overall activity. This preference persisted when the tadpoles had their optic nerve severed or pineal glands removed, suggesting these sensory systems alone are not necessary for phototaxis. These experiments were conducted by an undergraduate laboratory course, highlighting how X. laevis tadpole behavior assays in a classroom setting can reveal new insights into animal behavior.

Effective initial management of anastomotic leak in the maintenance of functional colorectal or coloanal anastomosis.

PURPOSE: The present study assessed the factors associated with the maintenance of a functional anastomosis in a large consecutive series of patients with anastomotic leakage (AL). METHODS: All consecutive patients presenting with AL after colorectal or coloanal anastomosis (2012-2019) were analyzed. The primary end point was a functional anastomosis without a stoma at 1 year. RESULTS: A total of 156 patients were included. AL was initially treated by antibiotics (38%), drainage (43%) or urgent surgery (19%). Initial treatment of AL was not adequate in 24.3%, and reintervention in the form of drainage or surgery was required. A total of 60.9% of patients had a functional anastomosis without a stoma 1 year after surgery. Factors associated with the risk of anastomotic failure at 1 year were diabetes (odds ratio [OR] = 4.24 [95% confidence interval {CI} 1.39-14.24] p = 0.014), neoadjuvant chemoradiotherapy (OR = 3.03 [95% CI 1.14-8.63] p = 0.03) and Grade B (OR = 6.49 [95% CI 2.23-21.74] p = 0.001) or C leak (OR = 35.35 [95% CI 9.36-168.21] p < 0.001). Among patients treated initially by drainage, side-to-end or J-pouch anastomoses were significantly associated with revision of the anastomosis compared to end-to-end (OR = 12.90, p = 0.04). CONCLUSION: After acute AL following coloanal or colorectal anastomosis, 60.9% of patients had a functional anastomosis without a stoma at the 1 year of follow-up. The type of treatment of AL influenced the risk of anastomotic failure.

Does an Ileoanal Anastomosis Decrease the Rate of Successful Pregnancy Compared With an Ileorectal Anastomosis? A National Study of 1491 Patients.

OBJECTIVE: Report the rate of successful pregnancy in a national cohort of women with either an ileal pouch anal (IPAA) or ileorectal (IRA) anastomosis constructed after colectomy for inflammatory bowel disease (IBD) or polyposis. BACKGROUND: Fertility after IPAA is probably impaired. All available data are corroborated by only small sample size studies. It is not known whether construction of IPAA versus IRA influences the odds of subsequently achieving a successful pregnancy, especially with increased utilization of the laparoscopic approach. METHODS: All women (age: 12-45 y) undergoing IRA or IPAA in France for polyposis or IBD, between 2010-2020, were included. A control population was defined as women aged from 12 to 45 years undergoing laparoscopic appendicectomy during the same period. The odds of successful pregnancy were studied using an adjusted survival analysis. RESULTS: A total of 1491 women (IPAA=872, 58%; IRA=619, 42%) were included. A total of 220 deliveries (15%) occurred during the follow-up period of 71 months (39-100). After adjustment, the odds of successful pregnancy was not significantly associated with type of anastomosis (after IPAA: Hazard Ratio [HR]=0.79, 95% confidence interval=0.56-1.11, P =0.17). The laparoscopic approach increased the odds of achieving successful pregnancy (HR=1.79, 95% confidence interval=1.20-2.63, P =0.004). IRA and IPAA significantly impacted fertility when compared with the control population ( P <0.001). CONCLUSIONS: In this large cohort study, total colectomy for polyposis or IBD was associated with reduced fertility compared with the general population. No difference in odds of achieving successful pregnancy was found between IRA and IPAA after adjustment. This analysis suggests laparoscopic surgery may be associated with greater likelihood of pregnancy.

Being and doing anorexia nervosa: An autoethnography of diagnostic identity and performance of illness.

This autoethnography examines my experience of the diagnosis and treatment of anorexia nervosa. Drawing on memory and personal and medical documents relating to inpatient admissions in an adult specialist eating disorder unit, I narrate and analyse my experience in terms of my relationship to the diagnosis of anorexia and the constructions of it I encountered. I show how I came to value an identity based on anorexia and how I learned ways of 'doing' the diagnosis in treatment. This involved me valuing medical markers of illness, including signs of poor health, which became crucial to how I performed my diagnosis and retained the diagnostically-informed sense of self that I valued. I suggest that, ultimately, these diagnostic-dynamics, alongside other effects of long-term inpatient treatment such as detachment from 'normal life', prolonged my struggles with self-starvation. The insights from this autoethnography shed light on potential iatrogenic impacts of diagnosis and treatment for anorexia.

Binding and sequestration of poison frog alkaloids by a plasma globulin.

Alkaloids are important bioactive molecules throughout the natural world, and in many animals they serve as a source of chemical defense against predation. Dendrobatid poison frogs bioaccumulate alkaloids from their diet to make themselves toxic or unpalatable to predators. Despite the proposed roles of plasma proteins as mediators of alkaloid trafficking and bioavailability, the responsible proteins have not been identified. We use chemical approaches to show that a ~50 kDa plasma protein is the principal alkaloid-binding molecule in blood of poison frogs. Proteomic and biochemical studies establish this plasma protein to be a liver-derived alkaloid-binding globulin (ABG) that is a member of the serine-protease inhibitor (serpin) family. In addition to alkaloid-binding activity, ABG sequesters and regulates the bioavailability of 'free' plasma alkaloids in vitro. Unexpectedly, ABG is not related to saxiphilin, albumin, or other known vitamin carriers, but instead exhibits sequence and structural homology to mammalian hormone carriers and amphibian biliverdin-binding proteins. ABG represents a new small molecule binding functionality in serpin proteins, a novel mechanism of plasma alkaloid transport in poison frogs, and more broadly points toward serpins acting as tunable scaffolds for small molecule binding and transport across different organisms.