Identifying Autism Spectrum Disorder in a High-risk Follow-up Program through Quality Improvement Methodology.

Introduction: Children born prematurely are at increased risk for autism spectrum disorder (ASD). ASD can be diagnosed between 18 and 24 months of age, but access barriers and medical complexity can delay diagnosis. ASD screening was implemented in a high-risk infant follow-up program using QI methodology. The project aimed to screen 60% of children and refer 90% of those with positive screens. Methods: The team developed a standardized workflow to administer the M-CHAT-R/F to HRIF patients between the ages of 16-22 months. Telehealth ASD assessment, using the TELE-ASD-PEDS, was conducted for those who screened positive. Monthly team meetings were held to implement change cycles and review the impact of the previous month's change. Results: Within 7 months of program implementation, ASD screening exceeded the 60% aim. The program referred 72% of patients who screened as medium/high risk on the M-CHAT-R/F. The remaining patients were not referred per provider discretion. Twenty-seven percent of patients who received an autism evaluation received an ASD diagnosis. The average age at diagnosis was 22.5 months. Conclusions: An ASD screening protocol was implemented for patients enrolled in a high-risk infant follow-up program. Patients identified as at risk for ASD received an expedited telehealth ASD evaluation. The screening protocol was maintained for 13 months and is now part of the standard workflow. Screening has been expanded to other HRIF clinics, and evaluation appointments have been added to meet access needs. QI methodology is an effective tool for implementing ASD screening and referral in multidisciplinary HRIF programs.

Shifting the Focus: A Photovoice exploration of the benefits and barriers of having a pet while experiencing homelessness.

While experiencing homelessness with a pet can present unique challenges, it can also provide physical health, mental health, and social benefits. A Photovoice project with adolescents and adults experiencing homelessness with a pet was conducted in Seattle, Washington, USA in 2018-2019 to explore the experience of homelessness with a pet, the impact of the human-animal bond on the health of each, and to drive policy changes to help support people experiencing homelessness (PEH) with pets. Twenty-five people spanning a range of age groups, genders, and living situations were recruited primarily through homeless-services providers, 19 of whom completed the study and created over 900 images. One-on-one semi-structured interviews were conducted with each participant to review printed photos. A key theme emerging from the interviews and photos was the importance and strength of the human-animal bond, providing mental and physical health benefits, and motivation for daily activities or making/maintaining positive changes. Challenges related to homelessness with a pet included barriers to access services, housing, and employment. Participants provided policy recommendations to improve support for PEH with pets. Multiple public exhibitions of images from all participants were held, reaching service providers, policy makers, and the general public. Visitor feedback included statements of positive change in attitudes towards PEH with pets among housed individuals. Collectively, the images, stories and themes deepen our understanding of homelessness with pets, leading to increased empathy and potential for policies that benefit the health of PEH and their pets.

Trends in Neonatal Opioid Withdrawal Syndrome and Opioid Exposure Diagnoses Among Infants With Private Health Insurance, 2016-2021: Introduction of the P04.14 ICD-10-CM Code.

OBJECTIVE: The opioid epidemic has led to a surge in diagnoses of neonatal opioid withdrawal syndrome (NOWS). Many states track the incidence of NOWS by using the P96.1 International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) code for "neonatal withdrawal symptoms from maternal use of drugs of addiction." In October 2018, an ICD-10-CM code for neonatal opioid exposure (P04.14) was introduced. This code can be used when an infant is exposed to opioids in utero but does not have clinically significant withdrawal symptoms. We analyzed the effect of the P04.14 code on the incidence rate of NOWS (P96.1) and "other" neonatal drug exposure diagnoses (P04.49). METHODS: We used private health insurance data collected for infants in the United States from the first quarter of 2016 through the third quarter of 2021 to describe incidence rates for each code over time and examine absolute and percentage changes before and after the introduction of code P04.14. RESULTS: The exclusive use of code P96.1 declined from an incidence rate per 1000 births of 1.08 in 2016-2018 to 0.70 in 2019-2021, a -35.7% (95% CI, -47.6% to -23.8%) reduction. Use of code P04.49 only declined from an incidence rate of 2.34 in 2016-2018 to 1.64 in 2019-2021, a -30.0% (95% CI, -36.4% to -23.7%) reduction. Use of multiple codes during the course of treatment increased from an average incidence per 1000 births of 0.56 in 2016-2018 to 0.79 in 2019-2021, a 45.5% (95% CI, 24.8%-66.1%) increase. CONCLUSION: The introduction of ICD-10-CM code P04.14 altered the use of other neonatal opioid exposure codes. The use of multiple codes increased, indicating that some ambiguity may exist about which ICD-10-CM code is most appropriate for a given set of symptoms.

2D and 3D multiplexed subcellular profiling of nuclear instability in human cancer.

Nuclear atypia, including altered nuclear size, contour, and chromatin organization, is ubiquitous in cancer cells. Atypical primary nuclei and micronuclei can rupture during interphase; however, the frequency, causes, and consequences of nuclear rupture are unknown in most cancers. We demonstrate that nuclear envelope rupture is surprisingly common in many human cancers, particularly glioblastoma. Using highly-multiplexed 2D and super-resolution 3D-imaging of glioblastoma tissues and patient-derived xenografts and cells, we link primary nuclear rupture with reduced lamin A/C and micronuclear rupture with reduced lamin B1. Moreover, ruptured glioblastoma cells activate cGAS-STING-signaling involved in innate immunity. We observe that local patterning of cell states influences tumor spatial organization and is linked to both lamin expression and rupture frequency, with neural-progenitor-cell-like states exhibiting the lowest lamin A/C levels and greatest susceptibility to primary nuclear rupture. Our study reveals that nuclear instability is a core feature of cancer, and links nuclear integrity, cell state, and immune signaling.

Generation of human steroidogenic cytochrome P450 enzymes for structural and functional characterization.

Six cytochrome P450 enzymes are involved in human steroidogenesis, converting cholesterol to sex steroids, mineralocorticoids, and glucocorticoids. While early work was accomplished with steroidogenic P450 orthologs from more accessible sources, knowledge of basic biochemistry through successful drug design have been greatly facilitated by recombinantly-expressed, highly purified human versions of these membrane proteins. Many membrane proteins are difficult to express and purify and are unstable. Membrane P450 expression in E. coli has been facilitated by modification and/or truncation of the membrane-interacting N-terminus, while metal-affinity resins and histidine-tagging greatly facilitates purification. However, substantial optimization is still frequently required to maintain protein stability. Over time, a generalized three-column purification scheme has been developed and tweaked to generate substantial quantities of fully active, highly purified human cytochrome P450 enzymes that have made possible the application of many structural, biochemical, and biophysical techniques to elucidate the mysteries of these critical human enzymes.

Selective steroidogenic cytochrome P450 haem iron ligation by steroid-derived isonitriles.

Alkyl isonitriles, R-NC, have previously been shown to ligate the heme (haem) iron of cytochromes P450 in both accessible oxidation states (ferrous, Fe2+, and ferric, Fe3+). Herein, the preparation of four steroid-derived isonitriles and their interactions with several P450s, including the steroidogenic CYP17A1 and CYP106A2, as well as the more promiscuous drug metabolizers CYP3A4 and CYP2D6, is described. It was found that successful ligation of the heme iron by the isonitrile functionality for a given P450 depends on both the position and stereochemistry of the isonitrile on the steroid skeleton. Spectral studies indicate that isonitrile ligation of the ferric heme is stable upon reduction to the ferrous form, with reoxidation resulting in the original complex. A crystallographic structure of CYP17A1 with an isonitrile derived from pregnanalone further confirmed the interaction and identified the absolute stereochemistry of the bound species.

Covariational reasoning and item context affect language in undergraduate mass balance written explanations.

Mass balance (MB) reasoning offers a rich topic for examination of students' scientific thinking and skills, as it requires students to account for multiple inputs and outputs within a system and apply covariational reasoning. Using previously validated constructed response prompts for MB, we examined 1,920 student-constructed responses (CRs) aligned to an emerging learning progression to determine how student language changes from low (1) to high (4) covariational reasoning levels. As students' abilities and thinking change with Context, we used the same general prompt in six physiological contexts. We asked how Level and Context affect student language and what language is conserved across Contexts at higher reasoning Levels. Using diversity methods, we found student language becomes more similar as covariational reasoning level increases. Using text analysis, we found context-dependent words at each Level; however, the type of context words changed. Specifically, at Level 1, students used context words that are tangential to MB reasoning, while Level 4 responses used words that specify inputs and outputs for the given Item Context. Further, at Level 4, students shared 30% of language across the six contexts and leveraged context-independent words including rate, equal, and some form of slower/lower/smaller. Together, these data demonstrate that Context affects undergraduate MB language at all covariational reasoning levels, but that the language becomes more specific and similar as Level increases. These findings encourage instructors to foster context-independent, comparative, and summative language during instruction to functionally build MB and covariational reasoning skills across contexts.NEW & NOTEWORTHY This article builds on the work of Scott et al. (Scott EE, Cerchiara J, McFarland JL, Wenderoth MP, Doherty JH. J Res Sci Teach 1: 37, 2023) and Shiroda et al. (Shiroda M, Fleming MP, Haudek KC. Front Educ 8: 989836, 2023) to quantitatively examine student language in written explanations of mass balance across six contexts using constructed response assessments. These results present an evaluation of student mass balance language and provide researchers and practitioners with tools to assist students in constructing scientific mass balance reasoning explanations.

Human cytochrome P450 3A7 binding four copies of its native substrate dehydroepiandrosterone 3-sulfate.

Human fetal cytochrome P450 3A7 (CYP3A7) is involved in both xenobiotic metabolism and the estriol biosynthetic pathway. Although much is understood about cytochrome P450 3A4 and its role in adult drug metabolism, CYP3A7 is poorly characterized in terms of its interactions with both categories of substrates. Herein, a crystallizable mutated form of CYP3A7 was saturated with its primary endogenous substrate dehydroepiandrosterone 3-sulfate (DHEA-S) to yield a 2.6 Å X-ray structure revealing the unexpected capacity to simultaneously bind four copies of DHEA-S. Two DHEA-S molecules are located in the active site proper, one in a ligand access channel, and one on the hydrophobic F'-G' surface normally embedded in the membrane. While neither DHEA-S binding nor metabolism exhibit cooperative kinetics, the current structure is consistent with cooperativity common to CYP3A enzymes. Overall, this information suggests that mechanism(s) of CYP3A7 interactions with steroidal substrates are complex.

Do Mental Health Changes in Nature Co-occur with Changes in Heartrate Variability and Executive Functioning? A Systematic Review.

PURPOSE OF REVIEW: Given the global burden of mental health issues, new solutions are needed to promote mental health. Nature exposure represents a promising option to promote mental health, but the mechanisms are poorly understood. Recent frameworks have argued that changes in mental health in nature are caused by activity changes in the vagus nerve, which connects the heart and the brain, and that these changes also improve executive functioning (EF) abilities. This suggests that changes in mental health symptomology in nature should be accompanied by changes in vagus nerve activity, as well as changes in executive functioning. Yet, little work has systematically examined co-variation of these outcomes in empirical studies. The present manuscript systematically examines whether changes in mental health in nature are accompanied by changes in vagus nerve activity (approximated by heartrate variability) and changes in executive functioning. RECENT FINDINGS: There is compelling evidence that spending time in nature can increase heartrate variability, improve mental health, and improve executive functioning. However, despite strong theoretical claims that these three outcomes should be linked after spending time in nature settings, few studies directly examine such co-occurrence. The study systematically examines whether studies that considered both mental health and executive functioning (n = 6) showed co-occurring effects in response to nature exposure. Similarly, the study also considers if studies examining mental health and heartrate variability (n = 6) showed similarly directional effects following nature exposure. This systematic review concludes with discussion about the limited number of studies (n =1) that include all three measures. We find mixed results of co-occurrence with these variables, suggesting that the relationship between these three constructs in nature may be more nuanced than current theory suggests. Perhaps more importantly, our results demonstrate that there is very little existing work linking changes in mental health to changes in EF and vagal tone. We conclude with justification for why it may be beneficial for researchers to include all three metrics as well as guidance on how to do so.

Allosteric modulation of cytochrome P450 enzymes by the NADPH cytochrome P450 reductase FMN-containing domain.

NADPH-cytochrome P450 reductase delivers electrons required by heme oxygenase, squalene monooxygenase, fatty acid desaturase, and 48 human cytochrome P450 enzymes. While conformational changes supporting reductase intramolecular electron transfer are well defined, intermolecular interactions with these targets are poorly understood, in part because of their transient association. Herein the reductase FMN domain responsible for interacting with targets was fused to the N-terminus of three drug-metabolizing and two steroidogenic cytochrome P450 enzymes to increase the probability of interaction. These artificial fusion enzymes were profiled for their ability to bind their respective substrates and inhibitors and to perform catalysis supported by cumene hydroperoxide. Comparisons with the isolated P450 enzymes revealed that even the oxidized FMN domain causes substantial and diverse effects on P450 function. The FMN domain could increase, decrease, or not affect total ligand binding and/or dissociation constants depending on both P450 enzyme and ligand. As examples, FMN domain fusion has no effect on inhibitor ketoconazole binding to CYP17A1 but substantially altered CYP21A2 binding of the same compound. FMN domain fusion to CYP21A2 resulted in differential effects dependent on whether the ligand was 17α-hydroxyprogesterone versus ketoconazole. Similar enzyme-specific effects were observed on steady-state kinetics. These observations are most consistent with FMN domain interacting with the proximal P450 surface to allosterically impact P450 ligand binding and metabolism separate from electron delivery. The variety of effects on different P450 enzymes and on the same P450 with different ligands suggests intricate and differential allosteric communication between the P450 active site and its proximal reductase-binding surface.

Burden of long COVID among adults experiencing sheltered homelessness: a longitudinal cohort study in King County, WA between September 2020-April 2022.

BACKGROUND: People experiencing homelessness (PEH) are at increased risk for acquiring SARS-CoV-2, but the burden of long COVID in this population is unknown. METHODS: We conducted a matched prospective cohort study to assess the prevalence, characteristics, and impact of long COVID among sheltered PEH in Seattle, WA between September 2020-April 2022. Adults ≥ 18 years, residing across nine homeless shelters with active respiratory virus surveillance, were eligible to complete in-person baseline surveys and interval follow-up phone surveys. We included a subset of 22 COVID-19-positive cases who tested positive or inconclusive for SARS-CoV-2 and 44 COVID-19-negative controls who tested negative for SARS-CoV-2, frequency matched on age and sex. Among controls, 22 were positive and 22 were negative for one of 27 other respiratory virus pathogens. To assess the impact of COVID-19 on the risk of symptom presence at follow-up (day 30-225 post-enrollment test), we performed log-linear regression with robust standard errors, adjusting for confounding by shelter site and demographic variables determined a priori. RESULTS: Of 53 eligible COVID-19 cases, 22 (42%) completed ≥ 1 follow-up survey. While five (23%) cases reported ≥ 1 symptom at baseline, this increased to 77% (10/13) between day 30-59 and 33% (4/12) day 90 + . The most commonly reported symptoms day 30 + were fatigue (27%) and rhinorrhea (27%), with 8 (36%) reporting symptoms that interfered with or prevented daily activities. Four (33%) symptomatic cases reported receiving medical care outside of a medical provider at an isolation facility. Of 44 controls, 12 (27%) reported any symptoms day 90 + . Risk of any symptoms at follow-up was 5.4 times higher among COVID-19 cases compared to controls (95% CI: 2.7-10.5). CONCLUSIONS: Shelter residents reported a high prevalence of symptoms 30 + days after their SARS-CoV-2 detection, though few accessed medical care for persistent illness. The impact of COVID-19 extends beyond acute illness and may exacerbate existing challenges that marginalized populations face in maintaining their health and wellbeing.

Updating the relationship of the Ne/ERN to task-related behavior: A brief review and suggestions for future research.

The error negativity/error-related negativity (Ne/ERN) is one of the most well-studied event-related potential (ERP) components in the electroencephalography (EEG) literature. Peaking about 50 ms after the commission of an error, the Ne/ERN is a negative deflection in the ERP waveform that is thought to reflect error processing in the brain. While its relationships to trait constructs such as anxiety are well-documented, there is still little known about how the Ne/ERN may subsequently influence task-related behavior. In other words, does the occurrence of the Ne/ERN trigger any sort of error corrective process, or any other behavioral adaptation to avoid errors? Several theories have emerged to explain how the Ne/ERN may implement or affect behavior on a task, but evidence supporting each has been mixed. In the following manuscript, we review these theories, and then systematically discuss the reasons that there may be discrepancies in the literature. We review both the inherent biological factors of the neural regions that underlie error-processing in the brain, and some of the researcher-induced factors in analytic and experimental choices that may be exacerbating these discrepancies. We end with a table of recommendations for future researchers who aim to understand the relationship between the Ne/ERN and behavior.

Health Disparities in Lapses in Diabetic Retinopathy Care.

Objective: To develop a novel methodology to identify lapses in diabetic retinopathy care in electronic health records (EHRs) and evaluate health disparities by race and ethnicity. Design: Retrospective cohort study. Subjects: Adult patients with diabetes mellitus who were evaluated at the Wilmer Eye Institute from January 1, 2013 to April 2, 2022. Methods: The methodology to identify lapses in care first identified diabetic retinopathy screening or treatment visits and then compared the providers' recommended follow-up timeframe with the patient's actual time to next encounter. The association of race and ethnicity with odds of lapses in care was evaluated using a mixed-effects logistic regression model controlling for age, sex, insurance, severity of diabetic retinopathy, presence of other retinal disorders, and glaucoma. Main Outcome Measures: Lapses in diabetic retinopathy care. Results: The methodology to identify diabetic retinopathy-related visits had a 95.0% (95% confidence interval, 93.0-96.6) sensitivity and 98.8% (98.1-99.3) specificity as compared with a gold standard grader. The methodology resulted in a 97.3% (96.2-98.4) sensitivity and 98.1% (97.3-98.9) specificity for detecting a follow-up recommendation, with an average error of -0.05 (-0.31 to 0.21) weeks in extracting the precise timeframe. A total of 39 561 patients with 91 104 office visits were included in the analysis. The average age was 61.4 years. More than 3 (77.6%) in 4 patients had a lapse in care. In multivariable analysis, non-Hispanic Black patients had 1.24 (1.19-1.30) odds and Hispanic patients had 1.26 (1.13-1.40) odds of ever having a lapse in care compared with non-Hispanic White patients (P < 0.001, respectively). Conclusions: We have developed a reliable methodology for identifying lapses in diabetic retinopathy care that is tailored to a provider's recommended follow-up. Using this approach, we find that 3 in 4 patients experience a lapse in diabetic retinopathy care and that these rates are higher among non-Hispanic Black and Hispanic patients. Deploying this methodology in the EHR is one potential means by which to identify and mitigate lapses in critical ophthalmic care in patients with diabetes. Financial Disclosures: Proprietary or commercial disclosure may be found after the references.

Measuring affect and complex working memory in natural and urban environments.

Introduction: Research suggests that spending time in natural environments is associated with cognitive and affective benefits, while increased use of technology and time spent in urban environments are associated with depletion of cognitive resources and an increasing prevalence of mental illness. Attention Restoration Theory suggests that exposure to natural environments can restore depleted attentional resources and thereby improve cognitive functioning and mood. Specifically, recent meta-analyses have revealed that the most improved cognitive abilities after nature exposure include selective attention, working memory, and cognitive flexibility. Methods: While existing studies examined these cognitive abilities, few have examined the Operation Span (OSPAN), a complex measure of working memory capacity. Therefore, the current study (N = 100) compared performance on the OSPAN and self-reported mood using the Positive and Negative Affect Schedule before and after a 30-min walk in a natural or urban environment. Results: Results from the study showed that both groups exhibited an increase in positive affect and a decrease in negative affect, suggesting that going outside for a walk can boost mood regardless of environment type. Inconsistent with past work, there were no significant changes in OSPAN scores before and after the walk for either environment type. Discussion: Future studies should analyze how the length of time spent in the environment, certain characteristics of the environment, and individual differences in connectedness to nature may impact attention restoration to gain insight on nature's ability to improve our affect and cognition.

What a Difference in Pressure Makes! A Framework Describing Undergraduate Students' Reasoning about Bulk Flow Down Pressure Gradients.

Pressure gradients serve as the key driving force for the bulk flow of fluids in biology (e.g., blood, air, phloem sap). However, students often struggle to understand the mechanism that causes these fluids to flow. To investigate student reasoning about bulk flow, we collected students' written responses to assessment items and interviewed students about their bulk flow ideas. From these data, we constructed a bulk flow pressure gradient reasoning framework that describes the different patterns in reasoning that students express about what causes fluids to flow and ordered those patterns into sequential levels from more informal ways of reasoning to more scientific, mechanistic ways of reasoning. We obtained validity evidence for this bulk flow pressure gradient reasoning framework by collecting and analyzing written responses from a national sample of undergraduate biology and allied health majors from 11 courses at five institutions. Instructors can use the bulk flow pressure gradient reasoning framework and assessment items to inform their instruction of this topic and formatively assess their students' progress toward more scientific, mechanistic ways of reasoning about this important physiological concept.

Oaks to arteries: the Physiology Core Concept of flow down gradients supports transfer of student reasoning.

The Physiology Core Concept of flow down gradients is a major concept in physiology, as pressure gradients are the key driving force for the bulk flow of fluids in biology. However, students struggle to understand that this principle is foundational to the mechanisms governing bulk flow across diverse physiological systems (e.g., blood flow, phloem sap flow). Our objective was to investigate whether bulk flow items that differ in scenario context (i.e., taxa, amount of scientific terminology, living or nonliving system) or in which aspect of the pressure gradient is kept constant (i.e., starting pressure or pressure gradient) influence undergraduate students' reasoning. Item scenario context did not impact the type of reasoning students used. However, students were more likely to use the Physiology Core Concept of "flow down [pressure] gradients" when the pressure gradient was kept constant and less likely to use this concept when the starting pressure was kept constant. We also investigated whether item scenario context or which aspect of the pressure gradient is kept constant impacted how consistent students were in the type of reasoning they used across two bulk flow items on the same homework. Most students were consistent across item scenario contexts (76%) and aspects of the pressure gradient kept constant (70%). Students who reasoned using "flow down gradients" on the first item were the most consistent (86, 89%), whereas students using "pressures indicate (but don't cause) flow" were the least consistent (43, 34%). Students who are less consistent know that pressure is somehow involved or indicates fluid flow but do not have a firm grasp of the concept of a pressure gradient as the driving force for fluid flow. These findings are the first empirical evidence to support the claim that using Physiology Core Concept reasoning supports transfer of knowledge across different physiological systems.NEW & NOTEWORTHY These findings are the first empirical evidence to support the claim that using Physiology Core Concept reasoning supports transfer of knowledge across different physiological systems.

Pyridine-containing substrate analogs are restricted from accessing the human cytochrome P450 8B1 active site by tryptophan 281.

The human oxysterol 12α-hydroxylase cytochrome P450 8B1 (CYP8B1) is a validated drug target for both type 2 diabetes and nonalcoholic fatty liver disease, but effective selective inhibitors are not yet available. Herein, steroidal substrate-mimicking compounds with a pyridine ring appended to the C12 site of metabolism were designed as inhibitors, synthesized, and evaluated in terms of their functional and structural interactions with CYP8B1. While the pyridine nitrogen was intended to coordinate the CYP8B1 active site heme iron, none of these compounds elicited shifts in the CYP8B1 Soret absorbance consistent with this type of interaction. However, when CYP8B1 was cocrystallized with the pyridine-containing compound with the 3-keto-Δ4 steroid backbone most similar to the endogenous substrate, it was apparent that this ligand was bound in a channel leading to the active site, instead of near the heme iron. Inspection of this structure suggested that tryptophan 281 directly above the heme might restrict active site binding of potential inhibitors with this design. This hypothesis was supported when a CYP8B1 W281F mutation did allow all three compounds to coordinate the heme iron as designed. These results indicated that the design of next-generation CYP8B1 inhibitors should be compatible with the low-ceiling tryptophan immediately above the heme iron.

Human cytochrome P450 17A1 structures with metabolites of prostate cancer drug abiraterone reveal substrate-binding plasticity and a second binding site.

Abiraterone acetate is a first-line therapy for castration-resistant prostate cancer. This prodrug is deacetylated in vivo to abiraterone, which is a potent and specific inhibitor of cytochrome P450 17A1 (CYP17A1). CYP17A1 performs two sequential steps that are required for the biosynthesis of androgens that drive prostate cancer proliferation, analogous to estrogens in breast cancer. Abiraterone can be further metabolized in vivo on the steroid A ring to multiple metabolites that also inhibit CYP17A1. Despite its design as an active-site-directed substrate analog, abiraterone and its metabolites demonstrate mixed competitive/noncompetitive inhibition. To understand their binding, we solved the X-ray structures of CYP17A1 with three primary abiraterone metabolites. Despite different conformations of the steroid A ring and substituents, all three bound in the CYP17A1 active site with the steroid core packed against the I helix and the A ring C3 keto or hydroxyl oxygen forming a hydrogen bond with N202 similar to abiraterone itself. The structure of CYP17A1 with 3-keto, 5α-abiraterone was solved to 2.0 Å, the highest resolution to date for a CYP17A1 complex. This structure had additional electron density near the F/G loop, which is likely a second molecule of the inhibitor and which may explain the noncompetitive inhibition. Mutation of the adjacent Asn52 to Tyr positions its side chain in this space, maintains enzyme activity, and prevents binding of the peripheral ligand. Collectively, our findings provide further insight into abiraterone metabolite binding and CYP17A1 function.

Health-Promoting Behaviours following Primary Treatment for Cancer: A Rural-Urban Comparison from a Cross-Sectional Study.

AIM: To compare health-promoting behaviours among rural and urban residents following primary treatment for cancer. METHODS: A cross-sectional survey collecting demographic variables and data pertaining to health-promoting behaviours, documented using the 52-item Health Promotion Lifestyle Profile II (HPLP-II) measure, which is categorised into six subscales: (1) health responsibility, (2) spiritual growth, (3) physical activity, (4) interpersonal relations, (5) nutrition, and (6) stress management. Residence was defined using the U.K. Office for National Statistics RUC 2011 Rural Urban Classifications. The Index of Multiple Deprivation (IMD) Decile was used to measure deprivation. Quantitative data were analysed using independent samples t-test and multiple linear regression. Qualitative data from open-ended questions were analysed thematically. RESULTS: In total, 227 participants with a range of cancer types completed the questionnaire. Fifty-three percent were residents in urban areas and forty-five percent in rural areas. Rural participants scored significantly higher on health responsibility (p = 0.001), nutrition (p = 0.001), spiritual growth (p = 0.004), and interpersonal relationships (p = 0.001), as well as on the overall HPLP-II (p = 0.001). When controlling for deprivation, age, marital status, and education, rural-urban residence was a significant predictor of exhibiting health-promoting behaviours. A central theme from the qualitative data was the concept of "moving on" from cancer following treatment, by making adjustments to physical, social, psychological, spiritual, and emotional wellbeing. CONCLUSIONS: This research revealed, for the first time, differences in health-promoting behaviours among rural and urban U.K. populations who have completed primary cancer treatment. Rural residence can provide a positive environment for engaging with health-promoting behaviours following a cancer diagnosis and treatment.