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Leukotriene A4 hydrolase (LTA4H) is a bifunctional enzyme, with dual activities critical in defining the scale of tissue inflammation and pathology. LTA4H classically operates intracellularly, primarily within myeloid cells, to generate pro-inflammatory leukotriene B4. However, LTA4H also operates extracellularly to degrade the bioactive collagen fragment proline-glycine-proline to limit neutrophilic inflammation and pathological tissue remodeling. While the dichotomous functions of LTA4H are dictated by location, the cellular source of extracellular enzyme remains unknown. We demonstrate that airway extracellular LTA4H concentrations are governed by the level of pulmonary vascular permeability and influx of an abundant repository of blood-borne enzyme. In turn, blood LTA4H originates from liver hepatocytes, being released constitutively but further upregulated during an acute phase response. These findings have implications for our understanding of how inflammation and repair are regulated and how perturbations to the LTA4H axis may manifest in pathologies of chronic diseases.
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Behavior analysts in research and clinical practice are interested in an ever-expanding array of topics. They are compelled to explore the social validity of the interventions they propose and the findings they generate. As the field moves in these important directions, qualitative methods are becoming increasingly relevant. Representing a departure from small-n design favored by behavior analysts, qualitative approaches provide analysts a unique set of tools to answer questions that prioritize voice, experience, and understandings in context. Despite recognition of the value of qualitative approaches in other disciplines, application of qualitative methods in behavior analysis remains limited. One likely explanation is that behavior analysts are not yet fluent in applying qualitative approaches within their clinical and research investigations. To address this issue, exploration of qualitative research approaches in behavior analytic literature is needed, alongside practical advice for analysts who are interested in using qualitative methods. This article briefly outlines qualitative literature which pertains to behavior analysts wanting to incorporate qualitative methods into their inquiries. Attention is primarily drawn to the need for coherence in designing and implementing a robust qualitative study that aligns with the behavior analyst's aims and perspective on knowing. A set of guiding questions are provided to orient behavior analysts to considerations in qualitative research and outline how analysts can conceptualize a strong qualitative study. This article aims to support increased application of qualitative methods by behavior analysts, where these methods best address the function of the behavior analytic investigation.
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The journey from phenotypic observation to causal genetic mechanism is a long and challenging road. For pathogens like Mycobacterium tuberculosis (Mtb), which causes tuberculosis (TB), host-pathogen coevolution has spanned millennia, costing millions of human lives. Mammalian models can systematically recapitulate host genetic variation, producing a spectrum of disease outcomes. Leveraging genome sequences and deep phenotyping data from infected mouse genetic reference populations (GRPs), quantitative trait locus (QTL) mapping approaches have successfully identified host genomic regions associated with TB phenotypes. Here, we review the ongoing optimization of QTL mapping study design alongside advances in mouse GRPs. These next-generation resources and approaches have enabled identification of novel host-pathogen interactions governing one of the most prevalent infectious diseases in the world today.
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Over a lifetime, hematopoietic stem and progenitor cells (HSPCs) are forced to repeatedly proliferate to maintain hematopoiesis, increasing their susceptibility to DNA damaging replication stress. However, the proteins that mitigate this stress, protect HSPC replication, and prevent aging-driven dysregulation are unknown. We report two evolutionarily conserved, ubiquitously expressed chromatin remodeling enzymes with similar DNA replication fork reversal biochemical functions, Zranb3 and Smarcal1, have surprisingly specialized roles in distinct HSPC populations. While both proteins actively mitigate replication stress and prevent DNA damage and breaks during lifelong hematopoiesis, the loss of either resulted in distinct biochemical and biological consequences. Notably, defective long-term HSC function, revealed with bone marrow transplantation, caused hematopoiesis abnormalities in young mice lacking Zranb3. Aging significantly worsened these hematopoiesis defects in Zranb3-deficient mice, including accelerating the onset of myeloid-biased hematopoietic dysregulation to early in life. Such Zranb3-deficient HSPC abnormalities with age were driven by accumulated DNA damage and replication stress. Conversely, Smarcal1 loss primarily negatively affected progenitor cell functions that were exacerbated with aging, resulting in a lymphoid bias. Simultaneous loss of both Zranb3 and Smarcal1 compounded HSPC defects. Additionally, HSPC DNA replication fork dynamics had unanticipated HSPC type and age plasticity that depended on the stress and Zranb3 and/or Smarcal1. Our data reveal both Zranb3 and Smarcal1 have essential HSPC cell intrinsic functions in lifelong hematopoiesis that protect HSPCs from replication stress and DNA damage in unexpected, unique ways.
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Clinical trials with single-agent venetoclax/ABT-199 (anti-apoptotic BCL2 inhibitor) revealed that diffuse large B-cell lymphoma (DLBCL) is not solely dependent on BCL2 for survival. Gaining insight into pathways/proteins that increase venetoclax sensitivity or unique vulnerabilities in venetoclax-resistant DLBCL would provide new potential treatment avenues. Therefore, we generated acquired venetoclax-resistant DLBCL cells and evaluated these together with intrinsically venetoclax-resistant and -sensitive DLBCL lines. We identified resistance mechanisms, including alterations in BCL2 family members that differed between intrinsic and acquired venetoclax resistance and increased dependencies on specific pathways. Although combination treatments with BCL2 family member inhibitors may overcome venetoclax resistance, RNA-sequencing and drug/compound screens revealed that venetoclax-resistant DLBCL cells, including those with TP53 mutation, had a preferential dependency on oxidative phosphorylation. Mitochondrial electron transport chain complex I inhibition induced venetoclax-resistant, but not venetoclax-sensitive, DLBCL cell death. Inhibition of IDH2 (mitochondrial redox regulator) synergistically overcame venetoclax resistance. Additionally, both acquired and intrinsic venetoclax-resistant DLBCL cells were similarly sensitive to inhibitors of transcription, B-cell receptor signaling, and class I histone deacetylases. These approaches were also effective in DLBCL, follicular, and marginal zone lymphoma patient samples. Our results reveal there are multiple ways to circumvent or overcome the diverse venetoclax resistance mechanisms in DLBCL and other B-cell lymphomas and identify critical targetable pathways for future clinical investigations.
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This protocol describes the method for creating 3D-printed trachea models for use in high-fidelity simulation-based training and advanced surgical planning for pediatric patients undergoing slide tracheoplasty. The goal is to provide a template and methodology to allow for replicability and more widespread dissemination of these models to improve clinical training and patient care. Laryngoscope, 2024.
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Fatigue crack propagation resistance and high-cycle S-N fatigue life of cortical bone allograft tissue are both negatively impacted in a radiation dose-dependent manner from 0 to 25 kGy. The standard radiation sterilization dose of 25-35 kGy has been shown to induce cleavage of collagen molecules into smaller peptides and accumulation of stable crosslinks within the collagen matrix, suggesting that these mechanisms may influence radiation-induced losses in cyclic fracture resistance. The objective of this study was to determine the radiation dose-dependency of collagen chain fragmentation and crosslink accumulation within the dose range of 0-25 kGy. Previously, cortical bone compact tension specimens from two donor femoral pairs were divided into four treatment groups (0 kGy, 10 kGy, 17.5 kGy, and 25 kGy) and underwent cyclic loading fatigue crack propagation testing. Following fatigue testing, collagen was isolated from one compact tension specimen in each treatment group from both donors. Radiation-induced collagen chain fragmentation was assessed using SDS-PAGE (n = 5), and accumulation of pentosidine, pyridinoline, and non-specific advanced glycation end products were assessed using a fluorometric assay (n = 4). Collagen chain fragmentation increased progressively in a dose-dependent manner (p < 0.001). Crosslink accumulation at all radiation dose levels increased relative to the 0 kGy control but did not demonstrate dose-dependency (p < 0.001). Taken together with our previous findings on fatigue crack propagation behavior, these data suggest that while collagen crosslink accumulation may contribute to reduced notched fatigue behavior with irradiation, dose-dependent losses in fatigue crack propagation resistance are mainly influenced by radiation-induced chain fragmentation.
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Inteligencia Artificial , Ortopedia , Humanos , Investigación Biomédica , Procedimientos OrtopédicosRESUMEN
Ten years ago, (black) stem rust - the most damaging of wheat (Triticum aestivum) rusts - re-emerged in western Europe. Disease incidences have since increased in scale and frequency. Here, we investigated the likely underlying causes and used those to propose urgently needed mitigating actions. We report that the first large-scale UK outbreak of the wheat stem rust fungus, Puccinia graminis f. sp. tritici (Pgt), in 2022 may have been caused by timely arrival of airborne urediniospores from southwest Europe. The drive towards later-maturing wheat varieties in the UK may be exacerbating Pgt incidences, which could have disastrous consequences. Indeed, infection assays showed that two UK Pgt isolates from 2022 could infect over 96% of current UK wheat varieties. We determined that the temperature response data in current disease risk simulation models are outdated. Analysis of germination rates for three current UK Pgt isolates showed substantial variation in temperature response functions, suggesting that the accuracy of disease risk simulations would be substantially enhanced by incorporating data from prevailing Pgt isolates. As Pgt incidences continue to accelerate in western Europe, we advocate for urgent action to curtail Pgt losses and help safeguard future wheat production across the region.
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Enfermedades de las Plantas , Tallos de la Planta , Triticum , Triticum/microbiología , Enfermedades de las Plantas/microbiología , Europa (Continente) , Tallos de la Planta/microbiología , Puccinia/patogenicidad , Puccinia/fisiología , Temperatura , Basidiomycota/fisiología , Basidiomycota/patogenicidad , Reino Unido/epidemiologíaRESUMEN
Introduction: While the relationship between narcissism and empathy has been well-researched, studies have paid less attention to empathic accuracy, i.e., appreciating the precise strength of another person's emotions, and self-other distinction, in terms of the disparity between affective ratings for self and other in response to emotive stimuli. Furthermore, empathic responses may vary depending on whether the pain is physical or social. Methods: We investigated empathic accuracy, affective empathy, and the distinction between pain, emotion and intensity ratings for self and other, in high (n = 44) and low (n = 43) narcissism groups (HNG and LNG, respectively) selected from 611 students, in response to both types of pain. Participants watched six videos where targets expressed genuine experiences of physical and social pain, and rated the perceived affect and pain experienced by the person in the video and their own empathic emotional responses. Results and discussion: The HNG displayed lower affective empathy and empathic accuracy than the LNG for both pain types. Within the HNG there was higher empathic accuracy for social vs. physical pain, despite reduced affective empathy for social pain, in contrast to the LNG. In addition to this paradox, the HNG demonstrated greater differences between ratings for the self and for target others than the LNG, suggesting that narcissism is associated with higher self-other distinction in response to viewing other people describing social pain.
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Competition over access to resources, such as food and mates, is believed to be one of the major costs associated with group living. Two socioecological factors suggested to predict the intensity of competition are group size and the relative abundance of sexually active individuals. However, empirical evidence linking these factors to injuries and survival costs is scarce. Here, we leveraged 10 years of data from free-ranging rhesus macaques where injuries inflicted by conspecifics are associated with a high mortality risk. We tested if group size and adult sex ratio predicted the occurrence of injuries and used data on physical aggression to contextualise these results. We found that males were less likely to be injured when living in larger groups, potentially due to advantages in intergroup encounters. Females, instead, had higher injury risk when living in larger groups but this was not explained by within-group aggression among females. Further, male-biased sex ratios predicted a weak increase in injury risk in females and were positively related to male-female aggression, indicating that male coercion during mating competition may be a cause of injuries in females. Overall, our results provide insights into sex differences in the fitness-related costs of competition and empirical evidence for long-standing predictions on the evolution of group living.
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Androgen signaling skews skin immunity toward reduced inflammation in male mice.
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Andrógenos , Caracteres Sexuales , Masculino , Femenino , Ratones , Animales , Inmunidad Innata , Linfocitos , Células DendríticasRESUMEN
AIM: To explore the training, involvement and confidence of healthcare professionals involved in decision-making capacity (DMC) assessments, and to compare any differences between those conducting and those involved in, but not conducting DMC assessments. METHOD: A 10-minute anonymous, online survey was conducted with both closed and open questions. A total of 78 participants completed the survey. RESULTS: Training was lacking in quantity and adequacy. Only 14.1% received formal training during and post their qualification and only 38.5% reported the right amount of training. Just over 55% reported having the right amount of involvement, with 18% having too much and 27% having not enough involvement. A significantly higher response was given for having too much involvement by those conducting DMC assessments (p=0.006), while those not conducting felt they do not have enough involvement (p<0.001). Only 25.6% (n=20) were very confident in being able to explain DMC to a patient. CONCLUSIONS: Healthcare professionals working in this area urgently require support in the form of formal training and defined roles. Given what can be at stake for an individual undergoing a DMC assessment, it is imperative that improvements are made to upskill the workforce and utilise expertise of all healthcare professionals.
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Toma de Decisiones , Personal de Salud , Humanos , Nueva Zelanda , Emociones , Atención a la SaludRESUMEN
Cold exposure increases blood pressure (BP) and salivary flow rate (SFR). Increased cold-induced SFR would be hypothesized to enhance oral nitrate delivery for reduction to nitrite by oral anaerobes and to subsequently elevate plasma [nitrite] and nitric oxide bioavailability. We tested the hypothesis that dietary nitrate supplementation would increase plasma [nitrite] and lower BP to a greater extent in cool compared with normothermic conditions. Twelve males attended the laboratory on four occasions. Baseline measurements were completed at 28°C. Subsequently, participants ingested 140 mL of concentrated nitrate-rich (BR; â¼13 mmol nitrate) or nitrate-depleted (PL) beetroot juice. Measurements were repeated over 3 h at either 28°C (Norm) or 20°C (Cool). Mean skin temperature was lowered compared with baseline in PL-Cool and BR-Cool. SFR was greater in BR-Norm, PL-Cool, and BR-Cool than PL-Norm. Plasma [nitrite] at 3 h was higher in BR-Cool (592 ± 239 nM) versus BR-Norm (410 ± 195 nM). Systolic BP (SBP) at 3 h was not different between PL-Norm (117 ± 6 mmHg) and BR-Norm (113 ± 9 mmHg). SBP increased above baseline at 1, 2, and 3 h in PL-Cool but not BR-Cool. These results suggest that BR consumption is more effective at increasing plasma [nitrite] in cool compared with normothermic conditions and blunts the rise in BP following acute cool air exposure, which might have implications for attenuating the increased cardiovascular strain in the cold.NEW & NOTEWORTHY Compared with normothermic conditions, acute nitrate ingestion increased plasma [nitrite], a substrate for oxygen-independent nitric oxide generation, to a greater extent during cool air exposure. Systolic blood pressure was increased during cool air exposure in the placebo condition with this cool-induced blood pressure increase attenuated after acute nitrate ingestion. These findings improve our understanding of environmental factors that influence nitrate metabolism and the efficacy of nitrate supplementation to lower blood pressure.
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Presión Sanguínea , Frío , Estudios Cruzados , Nitratos , Humanos , Masculino , Nitratos/administración & dosificación , Nitratos/sangre , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Método Doble Ciego , Adulto , Adulto Joven , Nitritos/sangre , Óxido Nítrico/metabolismo , Suplementos Dietéticos , Beta vulgaris , Temperatura Cutánea/efectos de los fármacos , Temperatura Cutánea/fisiología , Jugos de Frutas y VegetalesRESUMEN
Fundamental motor skills (FMS) are the cornerstone of a child's motor development, but concerns remain on the current level of FMS competencies, and intervention is required. This evaluation investigated if a targeted Early Years FMS intervention, delivered by a specialist physical education (PE) provider, improved the FMS of 4-5-year-old children across multiple sites. METHODS: The Early Years FMS intervention ran for 18 weeks, 1 h/week, using a standardised programme of activities to develop FMS competencies across 219 children from 15 schools in the Midlands, UK. An adapted assessment was employed as a measure of FMS, assessing locomotor, object control, and stability skills at weeks 1, 9, and 18. The FMS were each rated as green = competent, amber = working towards, or red = not meeting the standards of the skill. A description of key programme implementation characteristics was described. FINDINGS: Statistically significant increases in FMS competencies were achieved for 80% of participants at 18 weeks. Key implementation characteristics for the intervention included consistent staffing, a standardised programme, and a variety of pedagogical approaches delivered by specialist PE staff. CONCLUSION: This evaluation provided important insights into the effectiveness and implementation of the Early Years FMS intervention to improve FMS competencies in children aged 4-5 years.
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BACKGROUND: Burkitt lymphoma (BL) accounts for 10-35% of AIDS-defining lymphoma in people with HIV (PWH). Previous research consisting of smaller cohorts has shown decreased survival for HIV-associated BL. This study aims to compare overall mortality in BL patients with and without HIV, while investigating impact of treatment modalities in HIV-associated BL. METHODS: Using the 2004-2019 NCDB, we identified 4312 patients with stage 3 or 4 BL who had a known HIV status and received either chemotherapy alone or chemotherapy and immunotherapy. Time to death was evaluated using Kaplan-Meier survival estimates. Risk of death was evaluated using an extended multivariable Cox model adjusted for multiple factors and with a Heaviside function for HIV status by time period (0-3 month vs. 3-60 month). RESULTS: Of the 4312 patients included, 1514 (35%) had HIV. For months 0-3 from time of diagnosis, HIV status was not associated with a statistically significant increase in risk of death (HR = 1.04, 95% CI: 0.86, 1.26, p = 0.6648). From month 3to 60, positive HIV status was associated with a 55% increase in risk of death compared to those without HIV (95% CI: 1.38, 1.75, p < 0.0001). Further, this difference in hazard rates (0-3 vs. 3-60) was statistically significant (HR = 1.49, 95% CI: 1.22-1.82, p < 0.001). CONCLUSIONS: There is an increased mortality rate from months 3 to 60 in BL patients with HIV compared to patients without HIV. Additionally, risk of death in the first 3 months is significantly decreased by 45% in patients with HIV treated with combination chemotherapy and immunotherapy compared to patients without HIV receiving combination chemotherapy and immunotherapy, providing valuable clinical insight into treatment decision making in the care of HIV-associated BL.
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There is significant evidence that an unhealthy diet greatly increases the risk of complications during pregnancy and predisposes offspring to metabolic dysfunction and obesity. While fat intake is typically associated with the onset of obesity and its comorbidities, there is increasing evidence linking sugar, particularly high fructose corn syrup, to the global rise in obesity rates. Furthermore, the detrimental effects of added sugar intake during pregnancy on mother and child have been clearly outlined. Guidelines advising pregnant women to avoid food and beverages with high fat and sugar have led to an increase in consumption of 'diet' or 'light' options. Examination of some human birth cohort studies shows that heavy consumption (at least one beverage a day) of non-nutritive sweetener (NNS) containing beverages has been associated with increased risk of preterm birth and increased weight/BMI in male offspring independent of maternal weight, which appears to be offset by breastfeeding for 6 months. Rodent models have shown that NNS exposure during pregnancy can impact maternal metabolic health, adipose tissue function, gut microbiome profiles and taste preference. However, the mechanisms underlying these effects are multifaceted and further research, particularly in a translational setting is required to fully understand the effects of NNS on maternal and infant health during pregnancy. Therefore, this review examines maternal sweetener intakes and their influence on fertility, maternal health outcomes and offspring outcomes in human cohort studies and rodent models.
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BACKGROUND AND OBJECTIVE: The Prostate Cancer Radiological Estimation of Change in Sequential Evaluation (PRECISE) recommendations standardise the reporting of prostate magnetic resonance imaging (MRI) in patients on active surveillance (AS) for prostate cancer. An international consensus group recently updated these recommendations and identified the areas of uncertainty. METHODS: A panel of 38 experts used the formal RAND/UCLA Appropriateness Method consensus methodology. Panellists scored 193 statements using a 1-9 agreement scale, where 9 means full agreement. A summary of agreement, uncertainty, or disagreement (derived from the group median score) and consensus (determined using the Interpercentile Range Adjusted for Symmetry method) was calculated for each statement and presented for discussion before individual rescoring. KEY FINDINGS AND LIMITATIONS: Participants agreed that MRI scans must meet a minimum image quality standard (median 9) or be given a score of 'X' for insufficient quality. The current scan should be compared with both baseline and previous scans (median 9), with the PRECISE score being the maximum from any lesion (median 8). PRECISE 3 (stable MRI) was subdivided into 3-V (visible) and 3-NonV (nonvisible) disease (median 9). Prostate Imaging Reporting and Data System/Likert ≥3 lesions should be measured on T2-weighted imaging, using other sequences to aid in the identification (median 8), and whenever possible, reported pictorially (diagrams, screenshots, or contours; median 9). There was no consensus on how to measure tumour size. More research is needed to determine a significant size increase (median 9). PRECISE 5 was clarified as progression to stage ≥T3a (median 9). CONCLUSIONS AND CLINICAL IMPLICATIONS: The updated PRECISE recommendations reflect expert consensus opinion on minimal standards and reporting criteria for prostate MRI in AS. PATIENT SUMMARY: The Prostate Cancer Radiological Estimation of Change in Sequential Evaluation (PRECISE) recommendations are used in clinical practice and research to guide the interpretation and reporting of magnetic resonance imaging for patients on active surveillance for prostate cancer. An international panel has updated these recommendations, clarified the areas of uncertainty, and highlighted the areas for further research.