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1.
New Media Soc ; 26(5): 2804-2828, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38706952

RESUMO

Having a disability, in particular, an intellectual disability, is associated with Internet non-use. This article explores how people with intellectual disabilities used the Internet across the United Kingdom during the COVID-19 pandemic. In April to May 2021, 571 adults with intellectual disabilities were interviewed. Participants most commonly used the Internet for being with family and friends, social media or doing online activities with other people. People who lived with family were the most likely to use social media; people who lived with other people with intellectual disabilities were the least likely. People who self-reported as not lonely were more likely to use the Internet for online activities with others and play video games with others. Social connections were identified as the best thing about the Internet. Many participants chose not to identify a worst thing about Internet use, while others reported issues with technology, online harm and threats to well-being.

2.
Diagnostics (Basel) ; 14(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38732321

RESUMO

The present report describes the history of a 58-year-old woman with a rapidly progressing neuroendocrine pancreatic tumor (initially G2) presenting with extensive liver, bone, and lymph node metastases. Previous treatments included chemotherapy, hemithyroidectomy for right lobe metastasis, Peptide Receptor Radionuclide Therapy (PRRT) with [177Lu]Lu-DOTATATE, Lanreotide, Everolimus, and liver embolization. Due to severe disease progression, after a liver biopsy revealing tumor grade G3, PRRT with the somatostatin receptor antagonist LM3 was initiated. [68Ga]GaDOTA-LM3 PET/CT showed intense tracer uptake in the liver, pancreatic tumor, lymph nodes, and bone metastases. Three TANDEM-PRRT cycles using [177Lu]LuDOTA-LM3 and [225Ac]AcDOTA-LM3, administered concurrently, resulted in significant improvement, notably in liver metastases, hepatomegaly reduction, the complete regression of bone and lymph node metastases, and primary tumor improvement. Partial remission was confirmed by positron emission tomography/computed tomography, chest-abdomen-pelvis contrast-enhanced computed tomography, and magnetic resonance of the abdomen, with marked clinical improvement in pain, energy levels, and quality of life, enabling full resumption of physical activity.

3.
Appl Phys Lett ; 124(4)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38711922

RESUMO

A large-format mid-infrared single-photon imager with very low dark count rates would enable a broad range of applications in fields like astronomy and chemistry. Superconducting nanowire single-photon detectors (SNSPDs) are a mature photon-counting technology as demonstrated by their figures of merit such as high detection efficiencies and very low dark count rates. However, scaling SNSPDs to large array sizes for mid-infrared applications requires sophisticated readout architectures in addition to superconducting materials development. In this work, an SNSPD array design that combines a thermally coupled row-column multiplexing architecture with a thermally coupled time-of-flight transmission line was developed for mid-infrared applications. The design requires only six cables and can be scaled to larger array sizes. The demonstration of a 64-pixel array shows promising results for wavelengths between 3.4 µm and 10 µm, which will enable the use of this single-photon detector technology for a broad range of new applications.

6.
Cytotherapy ; 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38703154

RESUMO

One of the challenges in Good Manufacturing Practice (GMP)-compliant human induced pluripotent stem cell (hiPSC) production is the validation of quality control (QC) tests specific for hiPSCs, which are required for GMP batch release. This study presents a comprehensive description of the validation process for hiPSC-specific GMP-compliant QC assays; more specifically, the validation of assays to assess the potential presence of residual episomal vectors (REVs), the expression of markers of the undifferentiated state and the directed differentiation potential of hiPSCs. Critical aspects and specific acceptance criteria were formulated in a validation plan prior to assay validation. Assay specificity, sensitivity and reproducibility were tested, and the equipment used for each assay was subjected to performance qualification. A minimum input of 20 000 cells (120 ng of genomic DNA) was defined for accurate determination of the presence of REVs. Furthermore, since vector loss in hiPSC lines is a passage-dependent process, we advocate screening for REVs between passages eight and 10, as testing at earlier passages might lead to unnecessary rejection of hiPSC lines. The cutoff value for assessment of markers of the undifferentiated state was set to the expression of at least three individual markers on at least 75% of the cells. When multi-color flow cytometry panels are used, a fluorescence minus one control is advised to ensure the control for fluorescent spread. For the assay to assess the directed differentiation potential, the detection limit was set to two of three positive lineage-specific markers for each of the three individual germ layers. All of our assays proved to be reproducible and specific. Our data demonstrate that our implemented analytical procedures are suitable as QC assays for the batch release of GMP-compliant hiPSCs.

7.
Vaccine ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38704262

RESUMO

Social events may provide important cues that influence the sense of reality, including the perception that conspiracy theories are plausible. Using longitudinal panel data collected in the UK from March 2020 to December 2021, this study aims to identify whether social events influenced the strength of the association between conspiracy mentality and vaccine intentions during the COVID-19 pandemic. Consistent with previous research, the conspiracy mentality was a significant predictor of vaccine intentions across three-time points, but also that conspiracy mentality measured in March 2020 predicted that participants were more hesitant to the vaccines in December 2020. The primary finding was that different social events moderated the strength of the correlation between conspiracy mentality and vaccine intentions within similar participants. Conspiracy mentality became more vital to evaluate COVID-19 vaccines in December 2020, when the vaccination program was about to commence.

8.
J Am Coll Cardiol ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38739065

RESUMO

BACKGROUND: The 6-minute walk test (6MWT) represents a comprehensive functional assessment that is commonly used in patients with heart failure; however, data are lacking in patients with transthyretin cardiac amyloidosis (ATTR-CA). OBJECTIVES: This study aimed to assess the prognostic importance of the 6MWT in patients with ATTR-CA. METHODS: A retrospective analysis of patients diagnosed with ATTR-CA at the National Amyloidosis Centre who underwent a baseline 6MWT between 2011 and 2023 identified 2,141 patients, of whom 1,118 had follow-up at 1 year. RESULTS: The median baseline 6MWT distance was 347 m (Q1-Q3: 250-428 m) and analysis by quartiles demonstrated an increased death rate with each distance reduction (deaths per 100 person-years: 6.3 vs 9.2 vs 13.6 vs 19.0; log-rank P < 0.001). A 6MWT distance of <350 m was associated with a 2.2-fold higher risk of mortality (HR: 2.15; 95% CI: 1.85-2.50; P < 0.001), with a similar increased risk across National Amyloidosis Centre disease stages (P for interaction = 0.761) and genotypes (P for interaction = 0.172). An absolute (reduction of >35 m) and relative worsening (reduction of >5%) of 6MWT at 1 year was associated with an increased risk of mortality (HR: 1.80; 95% CI: 1.51-2.15; P < 0.001 and HR: 1.89; 95% CI: 1.59-2.24; P < 0.001, respectively), which was similar across the aforementioned subgroups. When combined with established measures of disease progression (N-terminal pro-B-type natriuretic peptide progression and outpatient diuretic intensification), each incremental increase in progression markers was associated with an increased death rate (deaths per 100 person-years: 7.6 vs 13.9 vs 22.4 vs 32.9; log-rank P < 0.001). CONCLUSIONS: The baseline 6MWT distance can refine risk stratification beyond traditional prognosticators. A worsening 6MWT distance can stratify disease progression and, when combined with established markers, identifies patients at the highest risk of mortality.

9.
Prostate ; 84(9): 823-831, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38606933

RESUMO

BACKGROUND: There are limited preclinical orthotopic prostate cancer models due to the technical complexity of surgical engraftment and tracking the tumor growth in the mouse prostate gland. Orthotopic xenografts recapitulate the tumor microenvironment, tumor stromal interactions, and clinical behavior to a greater extent than xenografts grown at subcutaneous or intramuscular sites. METHODS: This study describes a novel micro-surgical technique for orthotopically implanting intact tumors pieces from cell line derived (transgenic adenocarcinoma mouse prostate [TRAMP]-C2) or patient derived (neuroendocrine prostate cancer [NEPC]) tumors in the mouse prostate gland and monitoring tumor growth using magnetic resonance (MR) imaging. RESULTS: The TRAMP-C2 tumors grew rapidly to a predetermined endpoint size of 10 mm within 3 weeks, whereas the NEPC tumors grew at a slower rate over 7 weeks. The tumors were readily detected by MR and confidently identified when they were approximately 2-3 mm in size. The tumors were less well-defined on CT. The TRAMP-C2 tumors were characterized by amorphous sheets of poorly differentiated cells similar to a high-grade prostatic adenocarcinoma and frequent macroscopic peritoneal and lymph node metastases. In contrast, the NEPC's displayed a neuroendocrine morphology with polygonal cells arranged in nests and solid sheets and high count. There was a local invasion of the bladder and other adjacent tissues but no identifiable metastases. The TRAMP-C2 tumors were more hypoxic than the NEPC tumors. CONCLUSIONS: This novel preclinical orthotopic prostate cancer mouse model is suitable for either syngeneic or patient derived tumors and will be effective in developing and advancing the current selection of treatments for patients with prostate cancer.


Assuntos
Adenocarcinoma , Modelos Animais de Doenças , Neoplasias da Próstata , Animais , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Neoplasias da Próstata/diagnóstico por imagem , Camundongos , Humanos , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Linhagem Celular Tumoral , Camundongos Transgênicos , Transplante de Neoplasias/métodos , Imageamento por Ressonância Magnética , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/diagnóstico por imagem , Carcinoma Neuroendócrino/terapia
11.
Curr Cardiol Rep ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607539

RESUMO

PURPOSE OF REVIEW: Fabry Disease (FD) is a rare lysosomal storage disorder characterised by multiorgan accumulation of glycosphingolipid due to deficiency in the enzyme α-galactosidase A. Cardiac sphingolipid accumulation triggers various types of arrhythmias, predominantly ventricular arrhythmia, bradyarrhythmia, and atrial fibrillation. Arrhythmia is likely the primary contributor to FD mortality with sudden cardiac death, the most frequent cardiac mode of death. Traditionally FD was seen as a storage cardiomyopathy triggering left ventricular hypertrophy, diastolic dysfunction, and ultimately, systolic dysfunction in advanced disease. The purpose of this review is to outline the current evidence exploring novel mechanisms underlying the arrhythmia substrate. RECENT FINDINGS: There is growing evidence that FD cardiomyopathy is a primary arrhythmic disease with each stage of cardiomyopathy (accumulation, hypertrophy, inflammation, and fibrosis) contributing to the arrhythmia substrate via various intracellular, extracellular, and environmental mechanisms. It is therefore important to understand how these mechanisms contribute to an individual's risk of arrhythmia in FD. In this review, we outline the epidemiology of arrhythmia, pathophysiology of arrhythmogenesis, risk stratification, and cardiac therapy in FD. We explore how advances in conventional cardiac investigations performed in FD patients including 12-lead electrocardiography, transthoracic echocardiography, and cardiac magnetic resonance imaging have enabled early detection of pro-arrhythmic substrate. This has allowed for appropriate risk stratification of FD patients. This paves the way for future work exploring the development of therapeutic initiatives and risk prediction models to reduce the burden of arrhythmia.

12.
J Neurosurg Spine ; : 1-6, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669714

RESUMO

OBJECTIVE: Policy concern and debate surround the concept of overlapping spine surgery. Overlapping surgery specifically refers to nonessential portions of the case or noncutting time overlap. This differs from concurrent surgery, in which critical portions of the procedure overlap. Here the authors explore the barriers for safe and efficient overlapping surgery in academic spinal deformity practice. METHODS: Over a 24-month period, cases of spinal deformity, degenerative cases, anterior cervical discectomy and fusions (ACDFs), and laminectomy were reviewed for duration in operating room (OR) prior to surgery, duration of cutting time, duration in OR after surgery, turnover duration, and time delay from initial start time. Standard degenerative cases were referenced as 1-2 ACDFs as well as 1- to 2-level laminectomy surgery. The blocks of time between two consecutive cutting periods were investigated to determine the feasibility of overlapping an additional surgery. Specifically, the authors compared the blocks of time that include the postsurgery period, the turnover period, and the presurgery period to cutting periods. RESULTS: One hundred twenty-six complex spinal deformity procedures and 85 degenerative cases (including 49 ACDFs and 36 laminectomies) from one center and one neurosurgeon were reviewed. These procedures were performed between September 2019 and December 2021 with a 3-month gap in military deployment. On average, the procedure's duration for cases of deformity was 236.5 minutes, for cases of ACDFs it was 84 minutes, and for cases of laminectomies it was 105.5 minutes. The block of noncutting time while the patient was in the OR showed no difference from the surgical cut time. The turnover time between cases was 52.35 minutes. Of 100 cases scheduled as the first case of the day, 94 had a delay to the OR averaging 18.2 minutes. CONCLUSIONS: The data in this study indicate that estimates for pre- and postsurgical times alone are not sufficient to allow for overlapping surgery. The average cut-time duration of ACDF was 84 minutes; the average presurgical time for deformity was 68 minutes. This highlights the critical analysis for further examination of optimal scheduling, on-time first start, turnover periods, and the orchestration of all members of the providing team to optimize the cutting time for safe and consistent implementation of overlapping spine surgery.

13.
J Arthroplasty ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38604282

RESUMO

BACKGROUND: Wearable sensors and associated supporting technologies (ie, patient applications) can provide both objective (joint position, step counts, etc.) and subjective data (ie, pain scores and patient-reported outcome measures) to track a patient's episode of care. Establishing a subjective and objective baseline of a patient's experience may arguably be beneficial for multiple reasons, including setting recovery expectations for the patient and demonstrating the effectiveness or success of the intervention. METHODS: In this pilot study, we characterized a subset of patients (n = 82 from 7 surgeons) using a wearable sensor system at least 6 days before total knee arthroplasty and provided postsurgical data up to 50 days postintervention. The 5-day average before surgery for total step counts (activity), achieved flexion and extension on a progress test (functional limit) and visual analog scale daily pain score were calculated. The difference from baseline was then calculated for each patient for each day postsurgery and reported as averages. RESULTS: On average, a patient will experience a relative deficit of 4,000 steps immediately following surgery that will return to near-baseline levels 50 days postintervention. A 30° deficit in flexion and a 10° deficit in extension will return at a similar rate as steps. Relative pain scores will worsen with an increase of approximately 3 points immediately following surgery. However, pain will decrease by 2 points relative to baseline between 40 and 50 days. CONCLUSIONS: The results of this pilot study demonstrate a method to baseline a patient's presurgical subjective and objective data and to provide a reference for postsurgical recovery expectations. Applications for these data include benchmarking for evaluating intervention success as well as setting patient expectations.

14.
Proc Natl Acad Sci U S A ; 121(17): e2320239121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38630721

RESUMO

Collective motion is ubiquitous in nature; groups of animals, such as fish, birds, and ungulates appear to move as a whole, exhibiting a rich behavioral repertoire that ranges from directed movement to milling to disordered swarming. Typically, such macroscopic patterns arise from decentralized, local interactions among constituent components (e.g., individual fish in a school). Preeminent models of this process describe individuals as self-propelled particles, subject to self-generated motion and "social forces" such as short-range repulsion and long-range attraction or alignment. However, organisms are not particles; they are probabilistic decision-makers. Here, we introduce an approach to modeling collective behavior based on active inference. This cognitive framework casts behavior as the consequence of a single imperative: to minimize surprise. We demonstrate that many empirically observed collective phenomena, including cohesion, milling, and directed motion, emerge naturally when considering behavior as driven by active Bayesian inference-without explicitly building behavioral rules or goals into individual agents. Furthermore, we show that active inference can recover and generalize the classical notion of social forces as agents attempt to suppress prediction errors that conflict with their expectations. By exploring the parameter space of the belief-based model, we reveal nontrivial relationships between the individual beliefs and group properties like polarization and the tendency to visit different collective states. We also explore how individual beliefs about uncertainty determine collective decision-making accuracy. Finally, we show how agents can update their generative model over time, resulting in groups that are collectively more sensitive to external fluctuations and encode information more robustly.


Assuntos
Comportamento de Massa , Modelos Biológicos , Animais , Teorema de Bayes , Movimento , Movimento (Física) , Peixes , Comportamento Social , Comportamento Animal
15.
J Lipid Res ; : 100548, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38649096

RESUMO

DHA is abundant in brain where it regulates cell survival, neurogenesis and neuroinflammation. DHA can be obtained from the diet or synthesized from alpha-linolenic acid (ALA; 18:3n-3) via a series of desaturation and elongation reactions occurring in the liver. Tracer studies suggest that dietary DHA can downregulate its own synthesis, but the mechanism remains undetermined and is the primary objective of this paper. First, we show by tracing 13C content (δ13C) of DHA via compound-specific isotope analysis (CSIA), that following low dietary DHA, the brain receives DHA synthesized from ALA. We then show that dietary DHA increases mouse liver and serum EPA, which is dependant on ALA. Furthermore, by CSIA we demonstrate that the source of increased EPA is slowed EPA metabolism, not increased DHA retroconversion as previously assumed. DHA feeding alone or with ALA lowered liver elongation of very long-chain (ELOVL2, EPA elongation) enzyme activity despite no change in protein content. To further evaluate the role of ELOVL2, a liver-specific Elovl2 knockout was generated showing that DHA feeding in the presence or absence of a functional liver ELOVL2 yields similar results. An enzyme competition assay for EPA elongation suggests both uncompetitive and non-competitive inhibition by DHA depending on DHA levels. To translate our findings, we show that DHA supplementation in men and women increases EPA levels in a manner dependent on a SNP (rs953413) in the ELOVL2 gene. In conclusion, we identify a novel feedback inhibition pathway where dietary DHA downregulates its liver synthesis by inhibiting EPA elongation.

16.
Proc Natl Acad Sci U S A ; 121(16): e2320623121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38607930

RESUMO

Fine root lifespan is a critical trait associated with contrasting root strategies of resource acquisition and protection. Yet, its position within the multidimensional "root economics space" synthesizing global root economics strategies is largely uncertain, and it is rarely represented in frameworks integrating plant trait variations. Here, we compiled the most comprehensive dataset of absorptive median root lifespan (MRL) data including 98 observations from 79 woody species using (mini-)rhizotrons across 40 sites and linked MRL to other plant traits to address questions of the regulators of MRL at large spatial scales. We demonstrate that MRL not only decreases with plant investment in root nitrogen (associated with more metabolically active tissues) but also increases with construction of larger diameter roots which is often associated with greater plant reliance on mycorrhizal symbionts. Although theories linking organ structure and function suggest that root traits should play a role in modulating MRL, we found no correlation between root traits associated with structural defense (root tissue density and specific root length) and MRL. Moreover, fine root and leaf lifespan were globally unrelated, except among evergreen species, suggesting contrasting evolutionary selection between leaves and roots facing contrasting environmental influences above vs. belowground. At large geographic scales, MRL was typically longer at sites with lower mean annual temperature and higher mean annual precipitation. Overall, this synthesis uncovered several key ecophysiological covariates and environmental drivers of MRL, highlighting broad avenues for accurate parametrization of global biogeochemical models and the understanding of ecosystem response to global climate change.


Assuntos
Ecossistema , Longevidade , Evolução Biológica , Mudança Climática , Cabeça
17.
Eur J Psychotraumatol ; 15(1): 2330305, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590124

RESUMO

Military personnel and veterans are at heightened risk for exposure to traumatic events and posttraumatic stress disorder (PTSD), as well as intimate relationship problems associated with PTSD.The purpose of this study was to evaluate the relative efficacy of CBCT and PE in improving intimate relationship functioning in active duty military personnel or veterans and their intimate partners; both conditions were hypothesized to significantly improve PTSD. Method: In this study, 32 military service members or veterans with PTSD and their intimate partners were randomized to receive either Cognitive-Behavioral Conjoint Therapy for PTSD (n = 15; CBCT; [Monson, C. M., & Fredman, S. J. (2012). Cognitive-behavioral conjoint therapy for posttraumatic stress disorder: Harnessing the healing power of relationships. Guilford]), a trauma-focused couple therapy, or Prolonged Exposure (n = 17; PE; [Foa, E. B., Hembree, E. A., Dancu, C. V., Peterson, A. L., Cigrang, J. A., & Riggs, D. S. (2008). Prolonged exposure treatment for combat-related stress disorders - provider's treatment manual [unpublished]. Department of Psychiatry, University of Pennsylvania]), a front-line evidence-based individual treatment for PTSD.There were significant challenges with recruitment and a significant difference in dropout from treatment for the two therapies (65% for PE; 27% for CBCT). Treatment dropout was differentially related to pre-treatment relationship functioning; those with below average relationship functioning had higher dropout in PE compared with CBCT, whereas those with above average relationship functioning did not show differential dropout. In general, CBCT led to relational improvements, but this was not consistently found in PE. Clinician- and self-reported PTSD symptoms improved with both treatments.This study is the first to test a couple or family therapy against a well-established, front-line recommended treatment for PTSD, with expected superiority of CBCT over PE on relationship outcomes. Lessons learned in trial design, including considerations of equipoise, and the effects of differential dropout on trial analyses are discussed. This trial provides further support for the efficacy of CBCT in the treatment of PTSD and enhancement of intimate relationships.


Differential dropout from trial of couple versus individual therapy for PTSD.General pattern of improvements in relationship outcomes in couple therapy for PTSD.PTSD symptoms improved in the individual and couple therapy for PTSD.Lessons learned in trial design, including considerations of equipoise, and the effects of differential dropout by condition on trial analyses are discussed.


Assuntos
Militares , Transtornos de Estresse Pós-Traumáticos , Veteranos , Humanos , Transtornos de Estresse Pós-Traumáticos/terapia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Resultado do Tratamento , Cognição
18.
Br J Psychiatry ; : 1-6, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634312

RESUMO

BACKGROUND: Elevated risk of psychosis for ethnic minority groups has generally been shown to be mitigated by high ethnic density. However, past survey studies examining UK Pakistani populations have shown an absence of protective ethnic density effects, which is not observed in other South Asian groups. AIMS: To assess the ethnic density effect at a local neighbourhood level, in the UK Pakistani population in East Lancashire. METHOD: Data was collected by the East Lancashire Early Intervention Service, identifying all cases of first episode psychosis (FEP) within their catchment area between 2012 and 2020. Multilevel Poisson regression analyses were used to compare incidence rates between Pakistani and White majority groups, while controlling for age, gender and area-level deprivation. The ethnic density effect was also examined by comparing incidence rates across high and low density areas. RESULTS: A total of 455 cases of FEP (364 White, 91 Pakistani) were identified. The Pakistani group had a higher incidence of FEP compared to the White majority population. A clear effect of ethnic density on rates of FEP was shown, with those in low density areas having higher incidence rates compared to the White majority, whereas incidence rates in high density areas did not significantly differ. Within the Pakistani group, a dose-response effect was also observed, with risk of FEP increasing incrementally as ethnic density decreased. CONCLUSIONS: Higher ethnic density related to lower risk of FEP within the Pakistani population in East Lancashire, highlighting the impact of local social context on psychosis incidence.

19.
Integr Comp Biol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637295

RESUMO

Organisms produce antimicrobial peptides (AMPs) either in response to infection (induced) or continuously (constitutively) to combat microbes encountered during normal trophic activities and/or through pathogenic infections. The expression of AMPs is tightly regulated often with specificity to particular tissues or developmental stages. As a result, AMPs face varying selective pressures based on the microbes the organism's tissue or developmental stage encounters. Here, we analyzed the evolution and developmental-specific expression of Defensins, which are ancient AMPs in insects, in the stable fly (Stomoxys calcitrans). Stable fly larvae inhibit microbe-rich environments, whereas adult flies, as blood-feeders, experience comparatively fewer encounters with diverse microbial communities. Using existing RNA-seq datasets, we identified six Defensins that were only expressed in larvae (larval Defensins) and five that were not expressed in larvae (non-larval Defensins). Each of the non-larval Defensins was expressed in at least one adult tissue sample. Half of the larval Defensins were induced by mating or feeding in adults, and all three of the induced Defensins were located downstream of canonical binding sites for an Imd transcription factor involved in the highly conserved NF-κB signaling that regulates induction of AMPs. The larval and non-larval Defensins were located in distinct genomic regions, and the amino acid sequences of the larval Defensins formed a monophyletic clade. There were more amino acid substitutions across non-larval Defensins, with multiple genes losing a highly conserved furin cleavage site thought to be required for the removal of the amino terminus from the mature Defensin domain. However, larval Defensins had a higher proportion of radical amino acid substitutions, altering amino acid size and polarity. Our results reveal insights into the developmental stage-specific regulation of AMPs, and they suggest different regulatory regimes impose unique selection pressures on AMPs, possibly as a result of variation in exposure to microbial communities across development.

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