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HYPOTHESIS: Small scale Marangoni motors, which self-generate motion by inducing surface tension gradients on water interfaces through release of surface-active "fuels", have recently been proposed as self-powered mixing devices for low volume fluids. Such devices however, often show self-limiting lifespans due to the rapid saturation of surface-active agents. A potential solution to this is the use volatile surface-active agents which do not persist in their environment. Here we investigate menthyl acetate (MA) as a safe, inexpensive and non-persistent fuel for Marangoni motors. EXPERIMENTS: MA was loaded asymmetrically into millimeter scale silicone sponges. Menthyl acetate reacts slowly with water to produce the volatile surface-active menthol, which induces surface tension gradients across the sponge to drive motion by the Marangoni effect. Videos were taken and trajectories determined by custom software. Mixing was assessed by the ability of Marangoni motors to homogenize milliliter scale aqueous solutions containing colloidal sediments. FINDINGS: Marangoni motors, loaded with asymmetric "Janus" distributions of menthyl acetate show velocities and rotational speeds up to 30 mm s-1 and 500 RPM respectively, with their functional lifetimes scaling linearly with fuel volume. We show these devices are capable of enhanced mixing of solutions at orders of magnitude greater rates than diffusion alone.
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Abstract: Studies have found that blood flow to the renal medulla is an important determinant of pressure-natriuresis and the long-term regulation of arterial pressure. First, a brief review of methods developed enabling the study of the medullary circulation is presented. Second, studies performed in rats are presented showing medullary blood flow plays a vital role in the pressure-natriuresis relationship and thereby in hypertension. Third, it is shown that chronic reduction of medullary blood flow results in hypertension and that enhancement of medullary blood flow reduces hypertension hereditary models of both salt-sensitive rats and salt-resistant forms of hypertension. The key role that medullary nitric oxide production plays in protecting this region from ischemic injury associated with circulating vasoconstrictor agents and reactive oxygen species is presented. The studies cited are largely the work of my students, research fellows, and colleagues with whom I have performed these studies dating from the late 1980s to more recent years.
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Espécies Reativas de Oxigênio , Fluxometria por Laser-Doppler , Hipertensão , Natriurese , Óxido Nítrico , VasoconstritoresRESUMO
Background: The clinical course of idiopathic pulmonary fibrosis (IPF) is highly variable and unpredictable, with multiple genetic variants influencing IPF outcomes. Notably, rare pathogenic variants in telomere-related genes are associated with poorer clinical outcomes in these patients. Here we assessed whether rare qualifying variants (QVs) in monogenic adult-onset pulmonary fibrosis (PF) genes are associated with IPF survival. Using polygenic risk scores (PRS), we also evaluated the influence of common IPF risk variants in individuals carrying these QVs. Methods: We identified QVs in telomere and non-telomere genes linked to monogenic PF forms using whole-genome sequences (WGS) from 888 Pulmonary Fibrosis Foundation Patient Registry (PFFPR) individuals. We also derived a PRS for IPF (PRS-IPF) from 19 previously published common sentinel IPF variants. Using regression models, we then examined the mutual relationships of QVs and PRS-IPF and their association with survival. Validation of results was sought in WGS from an independent IPF study (PROFILE, n=472), and results from the two cohorts were meta-analyzed. Results: Carriers of QVs in monogenic adult-onset PF genes, representing nearly 1 out of 6 IPF patients, were associated with lower PRS-IPF (Odds Ratio [OR]: 1.79; 95% Confidence Interval [CI]: 1.15-2.81; p=0.010) and shorter survival (Hazard Ratio [HR]: 1.53; 95% CI: 1.12-2.10; p=7.3×10 -3 ). Notably, carriers of pathogenic variants at telomere genes showed the strongest association with survival (HR: 1.76; 95% CI: 1.13-2.76; p=0.013). The meta-analysis of the results showed a consistent direction of effect across both cohorts. Conclusions: We revealed the opposite effects of QVs and PRS-IPF on IPF survival. Thus, a distinct IPF molecular subtype might be defined by QVs in monogenic adult-onset PF genes. Assessing the carrier status for QVs and modelling PRS-IPF promises to further contribute to predicting disease progression among IPF patients.
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Myrtaceae are a large family of woody plants, including hundreds that are currently under threat from the global spread of a fungal pathogen, Austropuccinia psidii (G.Winter) Beenken, which causes myrtle rust. A reference genome for the Australian native rainforest tree Rhodamnia argentea Benth. (malletwood) was assembled from Oxford Nanopore Technologies (ONT) long-reads, 10x Genomics Chromium linked-reads, and Hi-C data (N50 = 32.3 Mbp and BUSCO completeness 98.0%) with 99.0% of the 347 Mbp assembly anchored to 11 chromosomes (2n = 22). The R. argentea genome will inform conservation efforts for Myrtaceae species threatened by myrtle rust, against which it shows variable resistance. We observed contamination in the sequencing data and further investigation revealed an arthropod source. This study emphasises the importance of checking sequencing data for contamination, especially when working with non-model organisms. It also enhances our understanding of a tree that faces conservation challenges, contributing to broader biodiversity initiatives.
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Patients with metastatic brain melanomas (MBM) experience shorter-lasting survival than patients with extracranial metastases, and this is associated with a higher fraction of dysfunctional CD8 T cells. The goal of this study was to understand the underlying cause of T cell dysfunction in MBM. To accomplish this, we compared murine B16 melanomas implanted intracranially (IC) or subcutaneously (SC). CD8 T cell activation was not altered, but representation in IC tumors was lower. Transferred activated or naïve CD8 T cells accumulated in similar numbers in both tumors, suggesting that the vasculature does not differentially impair T cell presence. Surprisingly, we found no evidence for T cell activation in draining lymph nodes of SC or IC tumor-bearing mice, consistent with the fact that dendritic cells (DC) that had acquired tumor antigen showed an immature phenotype. Instead, T cell activation occurred within both tumors, where the majority of tumor antigen+ myeloid cells were found. While, the numbers of intratumoral DC were comparable, those in IC tumors acquired less tumor antigen, and were alternatively matured based on upregulation of MHCII without upregulation of CD86. Additionally, in IC tumors, the largest population of tumor antigen+ myeloid cells were microglia. However, their presence did not influence either antigen acquisition or the phenotype of other myeloid cell populations. Overall, our data suggest that diminished representation of CD8 T cells in IC tumors is a consequence of alternatively matured DC and/or microglia that induce distinctly activated T cells, which ultimately fail to continue to accumulate inside the tumor.
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Neoplasias Encefálicas , Linfócitos T CD8-Positivos , Células Dendríticas , Melanoma Experimental , Melanoma , Camundongos Endogâmicos C57BL , Células Mieloides , Animais , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Camundongos , Células Mieloides/imunologia , Células Mieloides/metabolismo , Linfócitos T CD8-Positivos/imunologia , Melanoma/imunologia , Melanoma/patologia , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Ativação Linfocitária/imunologia , Feminino , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologiaRESUMO
The Notch receptor is activated by the Delta/Serrate/Lag-2 (DSL) family of ligands. The organization of the extracellular signaling complex is unknown, although structures of Notch/ligand complexes comprising the ligand-binding region (LBR), and negative regulatory region (NRR) region, have been solved. Here, we investigate the human Notch-1 epidermal growth factor-like (EGF) 20-27 region, located between the LBR and NRR, and incorporating the Abruptex (Ax) region, associated with distinctive Drosophila phenotypes. Our analyses, using crystallography, NMR and small angle X-ray scattering (SAXS), support a rigid, elongated organization for EGF20-27 with the EGF20-21 linkage showing Ca2+-dependent flexibility. In functional assays, Notch-1 variants containing Ax substitutions result in reduced ligand-dependent trans-activation. When cis-JAG1 was expressed, Notch activity differences between WT and Ca2+-binding Ax variants were less marked than seen in the trans-activation assays alone, consistent with disruption of cis-inhibition. These data indicate the importance of Ca2+-stabilized structure and suggest the balance of cis- and trans-interactions explains the effects of Drosophila Ax mutations.
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Intestinal smooth muscle differentiation is a complex physico-biological process involving several different pathways. Here, we investigate the properties of Ca2+ waves in the developing intestinal mesenchyme using GCamp6f expressing mouse embryos and investigate their relationship with smooth muscle differentiation. We find that Ca2+ waves are absent in the pre-differentiation mesenchyme and start propagating immediately following α-SMA expression. Ca2+ waves are abrogated by CaV1.2 and gap-junction blockers, but are independent of the Rho pathway. The myosine light-chain kinase inhibitor ML-7 strongly disorganized or abolished Ca2+ waves, showing that perturbation of the contractile machinery at the myosine level also affected the upstream Ca2+ handling chain. Inhibiting Ca2+ waves and contractility with CaV1.2 blockers did not perturb circular smooth muscle differentiation at early stages. At later stages, CaV1.2 blockers abolished intestinal elongation and differentiation of the longitudinal smooth muscle, leading instead to the emergence of KIT-expressing interstitial cells of Cajal at the gut periphery. CaV1.2 blockers also drove apoptosis of already differentiated, CaV1.2-expressing smooth muscle and enteric neural cells. We provide fundamental new data on Ca2+ waves in the developing murine gut and their relation to myogenesis in this organ.
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Sinalização do Cálcio , Diferenciação Celular , Mesoderma , Músculo Liso , Animais , Camundongos , Músculo Liso/metabolismo , Músculo Liso/embriologia , Mesoderma/metabolismo , Mesoderma/embriologia , Mesoderma/citologia , Cálcio/metabolismo , Canais de Cálcio Tipo L/metabolismo , Desenvolvimento Muscular , Intestinos/embriologia , Intestinos/citologiaRESUMO
Background: In the phase III SYNAPSE study, mepolizumab plus standard of care reduced total endoscopic nasal polyp score (NPS) versus that with placebo in patients with chronic rhinosinusitis with nasal polyps. Objective: Our aim was to investigate relationships between NPS and (1) peak nasal inspiratory flow (PNIF) and (2) patient-reported outcomes. Methods: In this post hoc analysis, patients randomized 1:1 received mepolizumab, 100 mg, or placebo subcutaneously every 4 weeks (plus standard of care). Changes from baseline in PNIF (week 52), visual analog scale scores (overall symptoms, nasal obstruction, and loss of smell [weeks 49-52]), and total 22-Item Sino-Nasal Outcome Test score (week 52) were assessed in patients with or without improvements in NPS (improvement of ≥1 point) or without (improvement of <1 point or worsening). Results: Patients with improvements in NPS had greater improvements in PNIF (a median of 50 L per minute [interquartile range (IQR) = 10.5-87.5] with mepolizumab vs a median of 40 L per minute [IQR = 0-85.0] with placebo) than did those patients without improvements in NPS (a median of 0.0 L per minute [IQR = -10.0 to 45.0] with mepolizumab vs a median of 0.0 L per minute [IQR = -30.0 to 30.0] with placebo). Similar results were seen for the following: change from baseline in overall symptoms (a median of -5.8 [IQR = -8.1 to -3.80] with mepolizumab and a median of -4.1 [IQR = -7.0 to -1.2] with placebo with improvement in NPS vs a median of -1.3 [IQR = -6.3 to 0.0] with mepolizumab and a median of -0.1 [IQR = -3.4 to 0.0] with placebo without improvement in NPS); change in nasal obstruction (a median of -5.7 [IQR = -8.2 to -3.5] with mepolizumab and a median of -4.5 [IQR = -7.3 to -1.2] with placebo with improvement in NPS vs a median of -1.3 [IQR = -6.6 to 0.0] with mepolizumab and a median of 0.0 [IQR = -3.6 to 0.0] with placebo without improvement in NPS); change in loss of smell (a median of -2.8 [IQR = -7.9 to 0.0] with mepolizumab and a median of -0.7 [IQR = -4.0 to 0.0] with placebo with improvement in NPS vs a median of 0.0 [IQR = -2.4 to 0.0] with mepolizumab and a median of 0.0 [IQR = -0.3 to 0.0]) with placebo without improvement in NPS); and change in visual analog scale score and 22-Item Sino-Nasal Outcome Test total score (a median of -37.0 [IQR = -52.0 to -24.0] with mepolizumab and a median of -29.0 [IQR = -43.0 to -9.0] with placebo with improvement in NPS vs a median of -16.0 [IQR = -42.0 to 0.0] with mepolizumab and a median of 0.0 [IQR = -27.0 to 0.0] with placebo without improvement in NPS). Conclusion: Improvement in NPS was associated with improvements in PNIF and patient-reported outcomes irrespective of treatment. PNIF could be a useful noninvasive tool for monitoring nasal polyp size.
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Objective: To describe patterns and variations in the medical and procedural management of early pregnancy loss (EPL) among reproductive endocrinology and infertility specialists, with attention to mifepristone use. Design: Cross-sectional. Setting: Online survey. Patients: Society for Reproductive Endocrinology and Infertility members. Intervention: Not applicable. Main Outcome Measure: Preferred management for EPL. Results: Of 101 completed surveys (response rate: 12.2%), 70.3% of respondents reported diagnosing EPL at least once per week. Half (50.5%) of respondents preferred medical management compared with 27.7% who preferred procedural management and 21.8% who preferred expectant management. Approximately one-quarter (26.7%) of respondents offer mifepristone for medical management of EPL. The most common reason cited for not prescribing mifepristone was a lack of access to the medication. Mifepristone prescribers were more likely to work in a hospital or university setting than private practice. Increasing years in practice was also associated with mifepristone use. The use of mifepristone for EPL did not vary by the respondent's age, gender, prior abortion training, or practice region. Conclusion: The most effective method of medical management uses both mifepristone and misoprostol. However, nearly three-quarters of reproductive endocrinology and infertility physicians do not offer mifepristone, which may be linked to access issues.
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BACKGROUND: The Hospital Frailty Risk Score (HFRS) has demonstrated strong correlation with adverse outcomes in various joint replacement surgeries, yet its applicability in total elbow arthroplasty (TEA) remains unexplored. The purpose of this study is to assess the association between HFRS and postoperative complications following elective primary TEA. METHODS: The Nationwide Readmissions Database was queried to identify patients undergoing primary TEA from 2016 to 2020. The HFRS was used to compare medical, surgical, and clinical outcomes of frail vs. non-frail patients. Mean and relative costs, total hospital length of stay (LOS), and discharge disposition for frail and non-frail patients were also compared. RESULTS: We identified 2,049 primary TEA in frail patients and 3,693 in non-frail patients. Frail patients had increased complication rates including acute respiratory failure (13.6% vs. 1.1%; p < 0.001), urinary tract infections (12.3% vs. 0.0%; p < 0.001), transfusions (3.9% vs. 1.1%; p < 0.001), pneumonia (1.1% vs. 0.2%; p < 0.001), acute respiratory distress syndrome (3.2% vs 0.6%; p < 0.001), sepsis (0.7% vs. 0.1%; p < 0.001), and hardware failure (1.2% vs 0.1%; p < 0.001). Frail patients also experienced higher rates of readmission (37% vs. 25%; p < 0.001) and death (1.7% vs. 0.2%; p < 0.001), while being less likely to undergo revision (6.5% vs. 17%; p < 0.001). Frail patients incurred higher healthcare costs ($28,497 vs. $23,377; p < 0.001) and longer LOS (5.3 days vs. 2.6 days; p < 0.001), with reduced likelihood of routine hospital stays (36% vs. 71%; p < 0.001) and increased utilization of short-term hospitalization (p < 0.001), care facilities (p < 0.001), and home health care services (p < 0.001). CONCLUSION: HFRS is a validated indicator of frailty and is strongly associated with increased rates of complications in patients undergoing elective primary TEA. These findings should be considered by orthopedic surgeons when assessing surgical candidacy and discussing treatment options in this at-risk patient population.
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Despite decades of research on yoga and depression, subjective experiences of participants in these studies have rarely been reported, and never in individuals receiving heated yoga for depression. We examined patient-reported qualitative findings from an 8-week randomized controlled trial of heated yoga for depression. Eighty medically healthy participants with moderate-to-severe depression were randomized to 8 weeks of at least twice-weekly heated yoga classes, derived from Bikram yoga, or a waitlist control. Fifty-seven participants received a clinician-administered exit interview at intervention completion/study withdrawal. The exit interview assessed: (1) how participants felt immediately following the heated yoga sessions (acute effects), (2) what they liked or found helpful about heated yoga over the 8-week intervention (positive effects), and (3) what they disliked/did not find helpful over the 8-week intervention (negative effects). Qualitative data were analyzed using thematic analysis. Acute improvements in depressive symptoms (i.e., immediately following yoga) were the most commonly reported (n = 44, 77.2%), followed by overall positive effects on depressive symptoms (i.e., over the course of the 8-week intervention; n = 33, 57.9%), including improvements in sleep (n = 10, 17.5%), energy (n = 13, 22.8%), mood (n = 18, 31.6%), motivation (n = 2, 3.5%), and concentration/decision-making (n = 5, 8.8%). Overall negative effects (i.e., over the course of the 8-week intervention) included dislike of various aspects of the intervention (n = 19, 33.3%), such as instruction (n = 7, 12.3%), difficulty (n = 7, 12.3%), repetitiveness (n = 3, 5.3%), class length (n = 2, 3.5%), and boredom (n = 7, 12.3%). Most participants reported both overall positive and negative effects (n = 37, 64.9%). Of the rest, 19 (33.3%) reported only overall positive effects, and 1 (1.8%) reported only overall negative effects. Most participant experiences were positive. Negative effects were less common and primarily involved dislike of different aspects of the heated yoga. The findings support strong acceptability and subjective improvement in depressive symptoms in depressed individuals.
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Depressão , Yoga , Humanos , Masculino , Feminino , Depressão/terapia , Pessoa de Meia-Idade , Adulto , Resultado do TratamentoRESUMO
Objectives: The last major UK survey of medical undergraduate rheumatology teaching was 25 years ago. This study aimed to describe current teaching practice, the perceptions of teachers and students and their engagement with Versus Arthritis teaching resources and future challenges and opportunities. Methods: Electronic surveys were distributed by e-mail and/or social media to relevant teachers and students identified within all 37 UK medical schools. Results: A total of 34/37 (91%) teacher and 30/37 (81%) student surveys were returned. Compared with the last survey, the proportion of schools delivering rheumatology-identifiable teaching has fallen from 100% to 86% and the mean number of teaching days from 30 to 10. Rheumatology teaching is now more dispersed throughout the curriculum. Students preferred active learning methods such as simulation and expert patient teaching, while teachers preferred small-group teaching, online learning and lectures. The Versus Arthritis resources appeared underutilized by students but were considered useful. Most students thought rheumatology careers were not promoted within their medical school. Conclusion: A decrease in dedicated rheumatology teaching time was noted since the last survey 25 years ago. Greater promotion of rheumatology as a speciality and future career is required to maintain its professional identity and prevent marginalization.
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Bacillus coagulans, a Gram-positive thermophilic bacterium, is recognized for its probiotic properties and recent development as a microbial cell factory. Despite its importance for biotechnological applications, the current understanding of B. coagulans' robustness is limited, especially for undomesticated strains. To fill this knowledge gap, we characterized the metabolic capability and performed functional genomics and systems analysis of a novel, robust strain, B. coagulans B-768. Genome sequencing revealed that B-768 has the largest B. coagulans genome known to date (3.94 Mbp), about 0.63 Mbp larger than the average genome of sequenced B. coagulans strains, with expanded carbohydrate metabolism and mobilome. Functional genomics identified a well-equipped genetic portfolio for utilizing a wide range of C5 (xylose, arabinose), C6 (glucose, mannose, galactose), and C12 (cellobiose) sugars present in biomass hydrolysates, which was validated experimentally. For growth on individual xylose and glucose, the dominant sugars in biomass hydrolysates, B-768 exhibited distinct phenotypes and proteome profiles. Faster growth and glucose uptake rates resulted in lactate overflow metabolism, which makes B. coagulans a lactate overproducer; however, slower growth and xylose uptake diminished overflow metabolism due to the high energy demand for sugar assimilation. Carbohydrate Transport and Metabolism (COG-G), Translation (COG-J), and Energy Conversion and Production (COG-C) made up 60%-65% of the measured proteomes but were allocated differently when growing on xylose and glucose. The trade-off in proteome reallocation, with high investment in COG-C over COG-G, explains the xylose growth phenotype with significant upregulation of xylose metabolism, pyruvate metabolism, and tricarboxylic acid (TCA) cycle. Strain B-768 tolerates and effectively utilizes inhibitory biomass hydrolysates containing mixed sugars and exhibits hierarchical sugar utilization with glucose as the preferential substrate.IMPORTANCEThe robustness of B. coagulans makes it a valuable microorganism for biotechnology applications; yet, this phenotype is not well understood at the cellular level. Through phenotypic characterization and systems analysis, this study elucidates the functional genomics and robustness of a novel, undomesticated strain, B. coagulans B-768, capable of utilizing inhibitory switchgrass biomass hydrolysates. The genome of B-768, enriched with carbohydrate metabolism genes, demonstrates high regulatory capacity. The coordination of proteome reallocation in Carbohydrate Transport and Metabolism (COG-G), Translation (COG-J), and Energy Conversion and Production (COG-C) is critical for effective cell growth, sugar utilization, and lactate production via overflow metabolism. Overall, B-768 is a novel, robust, and promising B. coagulans strain that can be harnessed as a microbial biomanufacturing platform to produce chemicals and fuels from biomass hydrolysates.
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BACKGROUND: Vitamin D deficiency has been associated with headaches in adults, but data for children with headaches are sparse. OBJECTIVE: To describe vitamin D levels in children with headaches. METHODS: We retrospectively analyzed serum 25(OH)D concentrations in children aged 2-17 years with headaches compared to children with epilepsy at the Children's Hospital of Eastern Ontario between October 1, 2014, and August 19, 2021. Serum 25(OH)D <50 nmol/L was classified as insufficient. RESULTS: Vitamin D concentrations of 353 children (117 with headaches; 236 with epilepsy) were analyzed. The median age in years was 10 (interquartile range [IQR] 5, 14); 50.4% of subjects were female. The median serum 25(OH)D was 56 nmol/L (IQR 41, 69) in children with headaches and 70 nmol/L (IQR 50, 95) in children with epilepsy. Vitamin D insufficiency was present in 42% of children with headaches and 25% of children with epilepsy (P = .002). In a multivariable linear regression model adjusting for age, sex and seasonality, children with headaches had serum 25(OH)D concentrations that were on average 9 nmol/L (95% CI-16.76, -0.96) lower compared to children with epilepsy (P = .029). CONCLUSION: The prevalence of vitamin D insufficiency is higher in children with headaches compared to children with epilepsy. Prospective studies are needed to assess if vitamin D supplementation may have a therapeutic effect on pediatric headaches.
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Johne's disease (JD; paratuberculosis) control programs have been regionally implemented across the globe, but few have successfully eradicated the pathogen (Mycobacterium avium ssp. paratuberculosis (MAP)) causing this disease. The limited success may partly be attributed to excluding young stock (calves and replacement heifers or bulls) from testing strategies aimed at identifying MAP-infected cattle. Young stock can shed MAP in feces and can have detectable MAP-specific antibodies in blood, as confirmed in experimentally and naturally infected cattle. Furthermore, MAP transmission causes new infections in young stock. Calves and heifers are often included in JD management strategies on dairy farms but excluded from conventional diagnostic tests due to a presumed lag between infection and detection of MAP shedding and/or MAP-specific serum antibodies. We summarize evidence of MAP shedding early in the course of infection and discuss promising diagnostics, testing and management strategies to support inclusion of young stock in JD control programs. Improvements in fecal Polymerase Chain Reaction, interferon-gamma release assay (IGRA), and enzyme-linked immunosorbent assay (ELISA) enable earlier detection of MAP and specific early immune responses. Studies on IGRA and ELISA have focused on evaluation of new antigens and optimal age of testing. There are new diagnostics, including phage-based tests to detect viable MAP, and gene expression patterns and metabolomics to detect MAP-infected young stock. In addition, refinements in testing and management of calves and heifers may enable reductions in MAP prevalence. We provide recommendations for dairy farmers, researchers, veterinarians, and other stakeholders that may improve JD control programs with an objective to control and potentially eradicate JD. Additionally, we have identified the most pressing gaps in knowledge that currently hamper inclusion of young stock in JD prevention and control programs. In summary, transmission among young stock may cause new MAP infections, and appropriate use of new diagnostic tests, testing and management strategies for young stock may improve the efficacy of JD control programs.
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The tumor suppressor p53 antagonizes tumorigenesis, notably including the suppression of T cell lymphomas while its role on physiological T cell biology including thymic T cell development has not been fully understood. Invariant natural killer T (iNKT) cells develop in the thymus as innate-like αß-T cells which consist of NKT1, NKT2 and NKT17 subsets. We found that the tumor suppressor p53 regulates specifically thymic NKT17 development. p53 is highly expressed in NKT17 relative to other T cell populations. Loss of p53 in the T cell lineage resulted in increased thymic NKT17 cell number with retention of lineage specific cytokine production, while development of NKT1, NKT2 and conventional T cells was not affected. Of interest, γH2AX expression was higher in NKT17 than NKT1 and NKT2 at steady state, and it was further increased in p53-deficient NKT17, suggesting that NKT17 development involves selectively greater DNA damage or genomic instability and that p53 expression might be in response to these damage signals. Taken together, our results indicated that the tumor suppressor p53 is active in selectively controlling thymic NKT17 development, with absence of p53 leading to an increase in thymic NKT17 cells expressing high levels of DNA damage response.
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The magnetic field in the Sun's corona stores energy that can be released to heat plasma and drive solar eruptions. Measurements of the global coronal magnetic field have been limited to several snapshots. In this work, we present observations, using the Upgraded Coronal Multi-channel Polarimeter, that provide 114 magnetograms of the global corona above the solar limb spanning ~8 months. We determined the magnetic field distribution with altitude in the corona and monitored the evolution at different latitudes over multiple solar rotations. The field strength between 1.05 and 1.60 solar radii varies from <1 to ~20 gauss. A signature of active longitudes appears in the coronal magnetic field measurements. Coronal models are generally consistent with our observations, though they have larger discrepancies in high-latitude regions.
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RATIONALE & OBJECTIVE: The benefits of kidney transplantation compared to treatment with dialysis, including in older adult, are primarily limited by the number of donated kidneys. We studied the potential to expand the use of older living kidney donors. STUDY DESIGN: Secondary analysis of the Berlin Initiative Study, a population-based cohort. SETTING: & Participants: 2069 adults aged ≥70 years in Germany. EXPOSURES: Age and sex. OUTCOMES: Suitability for living donation assessed by the absence of kidney-related exclusions for donation including albuminuria and low estimated glomerular filtration rate (eGFR) as well as absence of other medical exclusions. Willingness for living and deceased kidney donation assessed by participant survey. ANALYTICAL APPROACH: Descriptive analysis. RESULTS: Among the 2069 participants (median age 80 years, 53% women, median eGFR 63 ml/min/1.73m2), 93% had ≥1 medical contraindication for living donation at study entry unrelated to eGFR or albuminuria. Using two published eGFR and albuminuria thresholds for donor acceptance, 38% to 54% of participants had kidney-related exclusions for donation. Among the 5% to 6% of participants with neither medical nor kidney-related exclusions for living donation at baseline, 11% to 12% remained suitable for donation during 8 years of follow-up. Willingness for living or deceased donation was high (73% and 60%, respectively). LIMITATIONS: GFR was not measured and medical exclusions unrelated to eGFR and albuminuria were assessed using a cohort database complemented by claims data. CONCLUSIONS: One in twenty older adults were potentially suitable for living kidney donation and willingness for living donation was high. Further studies are warranted to define the feasibility of expanding living kidney donation among older adults.