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The impact of socio-economic status on the risk of allergy in African children is not clear.This was a cross sectional study including children aged 6–14 years from urban and rural settings in north-central Nigeria. Participants underwent... more
The impact of socio-economic status on the risk of allergy in African children is not clear.This was a cross sectional study including children aged 6–14 years from urban and rural settings in north-central Nigeria. Participants underwent skin prick tests to house dust mite (HDM) and an interview investigating socio-economic status through the Family Affluence Scale (FAS) based on a score of 0–6.A total of 346 children were enrolled (52.8% boys; mean age ± SD 9.6 ± 2.0 years), including 142 (41% of total) rural and 204 (59% of total) urban pupils. Prevalence of HDM sensitivity was 2.8% (4/142) in the rural setting and 15.6% (32/204) in the urban setting (P < 0.001). Among urban children, frequency of HDM sensitization was 8.6% (7/81) in the lowest socio-economic group (FAS 0–1), 13.1% (8/61) in the intermediate one (FAS 2–3) and 27.4% (17/62) in the highest one (FAS ≥ 4).Urbanization and increasing wealth are associated with a higher frequency of sensitization to HDM in Nigerian ...
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Macrophages are white blood cells with diverse functions contributing to a healthy immune response as well as the pathogenesis of cancer, osteoarthritis, atherosclerosis, and obesity. Due to their pleiotropic and dynamic nature, tools for... more
Macrophages are white blood cells with diverse functions contributing to a healthy immune response as well as the pathogenesis of cancer, osteoarthritis, atherosclerosis, and obesity. Due to their pleiotropic and dynamic nature, tools for imaging and tracking these cells at scales spanning the whole body down to microns could help to understand their role in disease states. Here we report fluorescent and radioisotopic quantum dots (QDs) for multimodal imaging of macrophage cells in vivo, ex vivo, and in situ. Macrophage specificity is imparted by click-conjugation to dextran, a biocompatible polysaccharide that natively targets these cell types. The emission spectral band of the crystalline semiconductor core was tuned to the near-infrared for optical imaging deep in tissue, and probes were covalently conjugated to radioactive iodine for nuclear imaging. The performance of these probes was compared with all-organic dextran probe analogues in terms of their capacity to target macrophages in visceral adipose tissue using in vivo positron emission tomography/computed tomography (PET/CT) imaging, in vivo fluorescence imaging, ex vivo fluorescence, post-mortem isotopic analyses, and optical microscopy. All probe classes exhibited equivalent physicochemical characteristics in aqueous solution and similar in vivo targeting specificity. However, dextran-mimetic QDs provided enhanced signal-to-noise ratio for improved optical quantification, long-term photostability, and resistance to chemical fixation. In addition, the vascular circulation time for the QD-based probes was extended 9-fold compared with dextran, likely due to differences in conformational flexibility. The enhanced photophysical and photochemical properties of dextran-mimetic QDs may accelerate applications in macrophage targeting, tracking, and imaging across broad resolution scales, particularly advancing capabilities in single-cell and single-molecule imaging and quantification.
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Peripheral arterial disease (PAD) manifests with a wide range of symptoms, from mild claudication to critical limb-threatening ischemia with tissue loss. Symptom severity is often a direct result of the increased atherosclerotic vascular... more
Peripheral arterial disease (PAD) manifests with a wide range of symptoms, from mild claudication to critical limb-threatening ischemia with tissue loss. Symptom severity is often a direct result of the increased atherosclerotic vascular burden and diminished limb arterial outflow. Current management paradigms ranges from conservative medical optimization that relies on antiplatelet and cholesterol lowering agents to invasive surgical intervention using endovascular, open, or hybrid approaches. However, this armamentarium is limited in its ability to encourage angiogenesis, especially when tissue loss has occurred. Contemporary attempts at inducing angiogenesis in patients with PAD using gene therapy have not yet been clinically efficacious. Thus, new therapeutic approaches to PAD are needed. In a new JVS Vascular Science article, Tsuruoka et al found a unique role for an essential element, zinc. Zinc encouraged angiogenesis and limb salvage in a murine model of limb ischemia and improved surface perfusion in patients with PAD requiring surgical intervention. Normally, zinc is implicated in cellular oxidative processes and has not been linked to angiogenic properties in the PAD population. In their study, the authors showed that in diet-induced, zinc-deficient mice, the ischemic wounds exhibited slower, less-efficient repair and decreased angiogenesis compared with their wild-type counterparts consuming normal chow. They subsequently studied patients who had undergone an index surgical intervention for critical limb-threatening ischemia and noted that those with increased serum levels of zinc had better bloodetissue perfusion postoperatively, implying that zinc is essential to limb salvage.
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The COVID-19 pandemic has had significant ramifications for provider well-being. During these unprecedented and challenging times, one institution's Department of Surgery put in place several important initiatives for promoting the... more
The COVID-19 pandemic has had significant ramifications for provider well-being. During these unprecedented and challenging times, one institution's Department of Surgery put in place several important initiatives for promoting the well-being of trainees as they were redeployed to provide care to COVID-19 patients. In this article, the authors describe these initiatives, which fall into 3 broad categories: redeploying faculty and trainees, ensuring provider safety, and promoting trainee wellness.The redeployment initiatives are the following: reframing the team mindset, creating a culture of grace and forgiveness, establishing a multidisciplinary wellness committee, promoting centralized leadership, providing clear communication, coordinating between departments and programs, implementing phased restructuring of the department's services, establishing scheduling flexibility and redundancy, adhering to training regulations, designating a trainee ombudsperson, assessing physical health risks for high-risk individuals, and planning for structured deimplementation.Initiatives specific to promoting provider safety are appointing a trainee safety advocate, guaranteeing personal protective equipment and relevant information about these materials, providing guidance regarding safe practices at home, and offering alternative housing options when necessary.Finally, the initiatives put in place to directly promote trainee wellness are establishing an environment of psychological safety, providing mental health resources, maintaining the educational missions, solidifying a sense of community by showing appreciation, being attentive to childcare, and using social media to promote community morale.The initiatives to carry out the department's strategy presented in this article, which were well received by both faculty and trainee members of the authors' community, may be employed in other departments and even outside the context of COVID-19. The authors hope that colleagues at other institutions and departments, independent of specialty, will find the initiatives described here helpful during, and perhaps after, the pandemic as they develop their own institution-specific strategies to promote trainee wellness.
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Significance The COVID-19 pandemic has disproportionately affected patients with comorbidities, namely, obesity and type 2 diabetes. Macrophages (Mφs) are a key innate immune cell primarily responsible for the harmful, hyperinflammatory... more
Significance The COVID-19 pandemic has disproportionately affected patients with comorbidities, namely, obesity and type 2 diabetes. Macrophages (Mφs) are a key innate immune cell primarily responsible for the harmful, hyperinflammatory “cytokine storm” in patients that develop severe COVID-19. We describe a mechanism for this Mφ-mediated cytokine storm in response to coronavirus. In response to coronavirus infection, expression of the chromatin-modifying enzyme, SETDB2, decreases in Mφs, leading to increased transcription of inflammatory cytokines. Further, we find SETDB2 is regulated by an interferon beta (IFNβ)/JaK/STAT3 mechanism, and that exogenous administration of IFNβ can reverse inflammation, particularly in diabetic Mφs via an increase in SETDB2. Together, these results suggest therapeutic targeting of the IFNβ/SETDB2 axis in diabetic patients with COVID-19 may decrease pathologic inflammation.
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Abdominal aortic aneurysms (AAAs) are a life-threatening disease for which there is a lack of effective therapy preventing aortic rupture. During AAA formation, pathological vascular remodeling is driven by macrophage infiltration, and... more
Abdominal aortic aneurysms (AAAs) are a life-threatening disease for which there is a lack of effective therapy preventing aortic rupture. During AAA formation, pathological vascular remodeling is driven by macrophage infiltration, and the mechanisms regulating macrophage-mediated inflammation remain undefined. Recent evidence suggests that an epigenetic enzyme, JMJD3, plays a critical role in establishing macrophage phenotype. Using single-cell RNA sequencing of human AAA tissues, we identified increased JMJD3 in aortic monocyte/macrophages resulting in up-regulation of an inflammatory immune response. Mechanistically, we report that interferon-β regulates Jmjd3 expression via JAK/STAT and that JMJD3 induces NF-κB–mediated inflammatory gene transcription in infiltrating aortic macrophages. In vivo targeted inhibition of JMJD3 with myeloid-specific genetic depletion (JMJD3f/fLyz2Cre+) or pharmacological inhibition in the elastase or angiotensin II–induced AAA model preserved the rep...
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NEMO is a scaffolding protein that, together with the catalytic subunits IKKα and IKKβ, plays an essential role in the formation of the IKK complex and in the activation of the canonical NF-κB pathway. Rational drug design targeting the... more
NEMO is a scaffolding protein that, together with the catalytic subunits IKKα and IKKβ, plays an essential role in the formation of the IKK complex and in the activation of the canonical NF-κB pathway. Rational drug design targeting the IKK-binding site on NEMO would benefit from structural insight, but to date, the determination of the structure of unliganded NEMO has been hindered by protein size and conformational heterogeneity. Here we show how the utilization of a homodimeric coiled-coil adaptor sequence stabilizes the minimal IKK-binding domain NEMO(44-111) and furthers our understanding of the structural requirements for IKK binding. The engineered constructs incorporating the coiled coil at the N-terminus, C-terminus, or both ends of NEMO(44-111) present high thermal stability and cooperative melting and, most importantly, restore IKKβ binding affinity. We examined the consequences of structural content and stability by circular dichoism and nuclear magnetic resonance (NMR) ...