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1.
World J Pediatr Congenit Heart Surg ; : 21501351241245115, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780414

RESUMO

Partial heart transplantation is a new approach to deliver growing heart valve implants. Partial heart transplants differ from heart transplants because only the part of the heart containing the necessary heart valve is transplanted. This allows partial heart transplants to grow, similar to the valves in heart transplants. However, the transplant biology of partial heart transplantation remains unexplored. This is a critical barrier to progress of the field. Without knowledge about the specific transplant biology of partial heart transplantation, children with partial heart transplants are empirically treated like children with heart transplants because the valves in heart transplants are known to grow. In order to progress the field, an animal model for partial heart transplantation is necessary. Here, we contribute our surgical protocol for partial heart transplantation in growing piglets. All aspects of partial heart transplantation, including the donor procedure, the recipient procedure, and recipient perioperative care are described in detail. There are important nuances in the conduct of virtually all aspects of open heart surgery that differs in piglets from humans. Our surgical protocol, which is based on our experience with 34 piglets, will allow other investigators to leverage our experience to seek fundamental knowledge about the nature of partial heart transplants. This is significant because the partial heart transplant model in piglets is complex and very resource intensive.

2.
Adv Healthc Mater ; : e2400237, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691819

RESUMO

Food allergy is a prevalent, potentially deadly disease caused by inadvertent sensitization to benign food antigens. Pathogenic Th2 cells are a major driver for disease, and allergen-specific immunotherapies (AIT) aim to increase the allergen threshold required to elicit severe allergic symptoms. However, the majority of AIT approaches require lengthy treatments and convey transient disease suppression, likely due to insufficient targeting of pathogenic Th2 responses. Here, the ability of allergen-encapsulating nanoparticles to directly suppress pathogenic Th2 responses and reactivity is investigated in a mouse model of food allergy. NPs associate with pro-tolerogenic antigen presenting cells, provoking accumulation of antigen-specific, functionally suppressive regulatory T cells in the small intestine lamina propria. Two intravenous doses of allergen encapsulated in poly(lactide-co-glycolide) nanoparticles (NPs) significantly reduces oral food challenge (OFC)-induced anaphylaxis. Importantly, NP treatment alters the fates of pathogenic allergen-specific Th2 cells, reprogramming these cells toward CD25+FoxP3+ regulatory and CD73+FR4+ anergic phenotypes. NP-mediated reductions in the frequency of effector cells in the gut and mast cell degranulation following OFC are also demonstrated. These studies reveal mechanisms by which an allergen-encapsulating NP therapy and, more broadly, allergen-specific immunotherapies, can rapidly attenuate allergic responses by targeting pathogenic Th2 cells.

4.
Front Cell Neurosci ; 18: 1321682, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469353

RESUMO

Mature oligodendrocytes (OLG) are the myelin-forming cells of the central nervous system. Recent work has shown a dynamic role for these cells in the plasticity of neural circuits, leading to a renewed interest in voltage-sensitive currents in OLG. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and their respective current (Ih) were recently identified in mature OLG and shown to play a role in regulating myelin length. Here we provide a biochemical and electrophysiological characterization of HCN channels in cells of the oligodendrocyte lineage. We observed that mice with a nonsense mutation in the Hcn2 gene (Hcn2ap/ap) have less white matter than their wild type counterparts with fewer OLG and fewer oligodendrocyte progenitor cells (OPCs). Hcn2ap/ap mice have severe motor impairments, although these deficits were not observed in mice with HCN2 conditionally eliminated only in oligodendrocytes (Cnpcre/+; Hcn2F/F). However, Cnpcre/+; Hcn2F/F mice develop motor impairments more rapidly in response to experimental autoimmune encephalomyelitis (EAE). We conclude that HCN2 channels in OLG may play a role in regulating metabolism.

6.
Arthrosc Sports Med Rehabil ; 6(2): 100886, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38328528

RESUMO

Purpose: To determine whether there was a relationship between sleep position and symptomatic partial- and full-thickness rotator cuff tears. Methods: A consecutive series of patients that met the inclusion/exclusion criteria (n = 58) were in seen in clinic between July 2019 and December 2019. All of these individuals had a significant partial-thickness (> 50%) or full-thickness rotator cuff tear determined by either ultrasound, magnetic resonance imaging, or both. All patients in this series either had an insidious onset of shoulder pain or their symptoms were related to the basic wear and tear of daily activities. Traumatic rotator cuff tears (those associated with a significant traumatic event such as shoulder instability, motor vehicle accidents, sports related injuries, etc.) were excluded. Previous shoulder surgery, recurrent rotator cuff tears, and worker's compensation cases also were excluded from this series. As part of the history-taking process, the patients were asked what was their preferred sleeping position-side sleeper, back sleeper, or stomach sleeper. A χ2 test was conducted to determine the relationship between rotator cuff pathology and sleep position. Results: Of the 58 subjects, 52 of the patients were side sleepers, 4 were stomach sleepers, 1 was a back sleeper, and 1 preferred all 3 positions. Statistical analysis, using the χ2 test (P < .0001), demonstrated that rotator cuff tears were most often seen in side sleepers. Conclusions: In our study, there appeared to be a relationship between the preference of being a side sleeper and the presence of a rotator cuff tear. Level of Evidence: Level IV, prognostic case series.

7.
JBI Evid Synth ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38328948

RESUMO

OBJECTIVE: The objective of this scoping review was to examine teaching approaches used to teach interprofessional health professional learners how to break bad news collaboratively. INTRODUCTION: When breaking bad news, health professionals must be equipped to deliver it skillfully and collaboratively; however, the literature shows that this skill receives little attention in program curricula. Consequently, health professionals can feel inadequately prepared to deliver bad news, which may lead to increased burnout, distress, and compassion fatigue. INCLUSION CRITERIA: Studies that describe teaching approaches used to teach learners how to break bad news collaboratively were considered for inclusion. Studies must have included 2 or more undergraduate and/or postgraduate learners working toward a professional health or social care qualification/degree at a university or college. Studies including lay, complementary and alternative, or non-health/social care learners were excluded. Due to the primary language of the research team, only English articles were included. METHODS: The JBI 3-step process was followed for developing the search. Databases searched included MEDLINE (Ovid), CINAHL (EBSCOhost), Embase, Education Resource Complete (EBSCOhost), and Social Work Abstracts (EBSCOhost). The initial search was conducted on February 11, 2021, and was updated on May 17, 2022. Title and abstract screening and data extraction were completed by 2 independent reviewers. Disagreements were resolved through discussion or with a third reviewer. Results are presented in tabular or diagrammatic format, together with a narrative summary. RESULTS: Thirteen studies were included in the scoping review, with a range of methodologies and designs (pre/post surveys, qualitative, feasibility, mixed methods, cross-sectional, quality improvement, and methodological triangulation). The majority of papers were from the United States (n=8; 61.5%). All but 1 study used simulation-enhanced interprofessional education as the preferred method to teach interprofessional cohorts of learners how to break bad news. The bulk of simulations were face-to-face (n=11; 84.6%). Three studies (23.1%) were reported as high fidelity, while the remainder did not disclose fidelity. All studies that used simulation to teach students how to break bad news utilized simulated participants/patients to portray patients and/or family in the simulations. The academic level of participants varied, with the majority noted as undergraduate (n=7; 53.8%); 3 studies (23.1%) indicated a mix of undergraduate and graduate participants, 2 (15.4%) were graduate only, and 1 (7.7%) was not disclosed. There was a range of health professional programs represented by participants, with medicine and nursing equally in the majority (n=10; 76.9%). CONCLUSIONS: Simulation-enhanced interprofessional education was the most reported teaching approach to teach interprofessional cohorts of students how to break bad news collaboratively. Inconsistencies were noted in the language used to describe bad news, use of breaking bad news and interprofessional competency frameworks, and integration of interprofessional education and simulation best practices. Further research should focus on other interprofessional approaches to teaching how to break bad news, how best to incorporate interprofessional competencies into interprofessional breaking bad news education, whether interprofessional education is enhancing collaborative breaking bad news, and whether what is learned about breaking bad news is being retained over the long-term and incorporated into practice. Future simulation-specific research should explore whether and how the Healthcare Simulation Standards of Best Practice are being implemented and whether simulation is resulting in student satisfaction and enhanced learning.

8.
JCI Insight ; 9(1)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38193532

RESUMO

Epilepsy has a profound impact on quality of life. Despite the development of new antiseizure medications (ASMs), approximately one-third of affected patients have drug-refractory epilepsy and are nonresponsive to medical treatment. Nearly all currently approved ASMs target neuronal activity through ion channel modulation. Recent human and animal model studies have implicated new immunotherapeutic and metabolomic approaches that may benefit patients with epilepsy. In this Review, we detail the proinflammatory immune landscape of epilepsy and contrast this with the immunosuppressive microenvironment in patients with glioma-related epilepsy. In the tumor setting, excessive neuronal activity facilitates immunosuppression, thereby contributing to subsequent glioma progression. Metabolic modulation of the IDH1-mutant pathway provides a dual pathway for reversing immune suppression and dampening seizure activity. Elucidating the relationship between neurons and immunoreactivity is an area for the prioritization and development of the next era of ASMs.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Glioma , Animais , Humanos , Qualidade de Vida , Epilepsia/tratamento farmacológico , Epilepsia/etiologia , Glioma/complicações , Glioma/tratamento farmacológico , Sistema Imunitário , Microambiente Tumoral
9.
Stud Health Technol Inform ; 310: 1086-1090, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38269982

RESUMO

Clinical trial enrollment is impeded by the significant time burden placed on research coordinators screening eligible patients. With 50,000 new cancer cases every year, the Veterans Health Administration (VHA) has made increased access for Veterans to high-quality clinical trials a priority. To aid in this effort, we worked with research coordinators to build the MPACT (Matching Patients to Accelerate Clinical Trials) platform with a goal of improving efficiency in the screening process. MPACT supports both a trial prescreening workflow and a screening workflow, employing Natural Language Processing and Data Science methods to produce reliable phenotypes of trial eligibility criteria. MPACT also has a functionality to track a patient's eligibility status over time. Qualitative feedback has been promising with users reporting a reduction in time spent on identifying eligible patients.


Assuntos
Neoplasias , Tecnologia , Humanos , Fluxo de Trabalho , Ciência de Dados , Definição da Elegibilidade , Neoplasias/diagnóstico , Neoplasias/terapia
10.
Brain ; 147(4): 1344-1361, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37931066

RESUMO

Neuromyelitis optica spectrum disorder (NMOSD) is a CNS autoimmune inflammatory disease mediated by T helper 17 (Th17) and antibody responses to the water channel protein, aquaporin 4 (AQP4), and associated with astrocytopathy, demyelination and axonal loss. Knowledge about disease pathogenesis is limited and the search for new therapies impeded by the absence of a reliable animal model. In our work, we determined that NMOSD is characterized by decreased IFN-γ receptor signalling and that IFN-γ depletion in AQP4201-220-immunized C57BL/6 mice results in severe clinical disease resembling human NMOSD. Pathologically, the disease causes autoimmune astrocytic and CNS injury secondary to cellular and humoral inflammation. Immunologically, the absence of IFN-γ allows for increased expression of IL-6 in B cells and activation of Th17 cells, and generation of a robust autoimmune inflammatory response. Consistent with NMOSD, the experimental disease is exacerbated by administration of IFN-ß, whereas repletion of IFN-γ, as well as therapeutic targeting of IL-17A, IL-6R and B cells, ameliorates it. We also demonstrate that immune tolerization with AQP4201-220-coupled poly(lactic-co-glycolic acid) nanoparticles could both prevent and effectively treat the disease. Our findings enhance the understanding of NMOSD pathogenesis and provide a platform for the development of immune tolerance-based therapies, avoiding the limitations of the current immunosuppressive therapies.


Assuntos
Neuromielite Óptica , Humanos , Animais , Camundongos , Neuromielite Óptica/patologia , Aquaporina 4 , Interferon gama/metabolismo , Camundongos Endogâmicos C57BL , Linfócitos B , Autoanticorpos/metabolismo
11.
J Allergy Clin Immunol ; 153(3): 549-559, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37926124

RESUMO

Food allergy is a growing public health issue among children and adults that can lead to life-threatening anaphylaxis following allergen exposure. The criterion standard for disease management includes food avoidance and emergency epinephrine administration because current allergen-specific immunotherapy treatments are limited by adverse events and unsustained desensitization. A promising approach to remedy these shortcomings is the use of nanoparticle-based therapies that disrupt disease-driving immune mechanisms and induce more sustained tolerogenic immune pathways. The pathophysiology of food allergy includes multifaceted interactions between effector immune cells, including lymphocytes, antigen-presenting cells, mast cells, and basophils, mainly characterized by a TH2 cell response. Regulatory T cells, TH1 cell responses, and suppression of other major allergic effector cells have been found to be major drivers of beneficial outcomes in these nanoparticle therapies. Engineered nanoparticle formulations that have shown efficacy at reducing allergic responses and revealed new mechanisms of tolerance include polymeric-, lipid-, and emulsion-based nanotherapeutics. This review highlights the recent engineering design of these nanoparticles, the mechanisms induced by them, and their future potential therapeutic targets.


Assuntos
Hipersensibilidade Alimentar , Nanopartículas , Criança , Adulto , Humanos , Dessensibilização Imunológica , Alimentos , Alérgenos
13.
Cell Chem Biol ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38056465

RESUMO

Selective and precise activation of signaling transduction cascades is key for cellular reprogramming and tissue regeneration. However, the development of small- or large-molecule agonists for many signaling pathways has remained elusive and is rate limiting to realize the full clinical potential of regenerative medicine. Focusing on the Wnt pathway, here we describe a series of disulfide-constrained peptides (DCPs) that promote Wnt signaling activity by modulating the cell surface levels of ZNRF3, an E3 ubiquitin ligase that controls the abundance of the Wnt receptor complex FZD/LRP at the plasma membrane. Mechanistically, monomeric DCPs induce ZNRF3 ubiquitination, leading to its cell surface clearance, ultimately resulting in FZD stabilization. Furthermore, we engineered multimeric DCPs that induce expansive growth of human intestinal organoids, revealing a dependence between valency and ZNRF3 clearance. Our work highlights a strategy for the development of potent, biologically active Wnt signaling pathway agonists via targeting of ZNRF3.

14.
NPJ Regen Med ; 8(1): 61, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919305

RESUMO

In acute skin injury, healing is impaired by the excessive release of reactive oxygen species (ROS). Melanin, an efficient scavenger of radical species in the skin, performs a key role in ROS scavenging in response to UV radiation and is upregulated in response to toxic insult. In a chemical injury model in mice, we demonstrate that the topical application of synthetic melanin particles (SMPs) significantly decreases edema, reduces eschar detachment time, and increases the rate of wound area reduction compared to vehicle controls. Furthermore, these results were replicated in a UV-injury model. Immune array analysis shows downregulated gene expression in apoptotic and inflammatory signaling pathways consistent with histological reduction in apoptosis. Mechanistically, synthetic melanin intervention increases superoxide dismutase (SOD) activity, decreases Mmp9 expression, and suppresses ERK1/2 phosphorylation. Furthermore, we observed that the application of SMPs caused increased populations of anti-inflammatory immune cells to accumulate in the skin, mirroring their decrease from splenic populations. To enhance antioxidant capacity, an engineered biomimetic High Surface Area SMP was deployed, exhibiting increased wound healing efficiency. Finally, in human skin explants, SMP intervention significantly decreased the damage caused by chemical injury. Therefore, SMPs are promising and effective candidates as topical therapies for accelerated wound healing, including via pathways validated in human skin.

15.
Genet Sel Evol ; 55(1): 76, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919645

RESUMO

BACKGROUND: Hoof structure and health are essential for the welfare and productivity of beef cattle. Therefore, we assessed the genetic and genomic background of foot score traits in American (US) and Australian (AU) Angus cattle and investigated the feasibility of performing genomic evaluations combining data for foot score traits recorded in US and AU Angus cattle. The traits evaluated were foot angle (FA) and claw set (CS). In total, 109,294 and ~ 1.12 million animals had phenotypic and genomic information, respectively. Four sets of analyses were performed: (1) genomic connectedness between US and AU Angus cattle populations and population structure, (2) estimation of genetic parameters, (3) single-step genomic prediction of breeding values, and (4) single-step genome-wide association studies for FA and CS. RESULTS: There was no clear genetic differentiation between US and AU Angus populations. Similar heritability estimates (FA: 0.22-0.24 and CS: 0.22-0.27) and moderate-to-high genetic correlations between US and AU foot scores (FA: 0.61 and CS: 0.76) were obtained. A joint-genomic prediction using data from both populations outperformed within-country genomic evaluations. A genomic prediction model considering US and AU datasets as a single population performed similarly to the scenario accounting for genotype-by-environment interactions (i.e., multiple-trait model considering US and AU records as different traits), even though the genetic correlations between countries were lower than 0.80. Common significant genomic regions were observed between US and AU for FA and CS. Significant single nucleotide polymorphisms were identified on the Bos taurus (BTA) chromosomes BTA1, BTA5, BTA11, BTA13, BTA19, BTA20, and BTA23. The candidate genes identified were primarily from growth factor gene families, including FGF12 and GDF5, which were previously associated with bone structure and repair. CONCLUSIONS: This study presents comprehensive population structure and genetic and genomic analyses of foot scores in US and AU Angus cattle populations, which are essential for optimizing the implementation of genomic selection for improved foot scores in Angus cattle breeding programs. We have also identified candidate genes associated with foot scores in the largest Angus cattle populations in the world and made recommendations for genomic evaluations for improved foot score traits in the US and AU.


Assuntos
Estudo de Associação Genômica Ampla , Genoma , Bovinos/genética , Animais , Estudo de Associação Genômica Ampla/veterinária , Austrália , Fenótipo , Genótipo , Genômica , Polimorfismo de Nucleotídeo Único
16.
Toxicon ; 234: 107284, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37683700

RESUMO

Snakebite envenoming (SBE) is common in rural communities living in tropical regions that often have fragile and/or overwhelmed healthcare systems. The complex scenarios around SBE lead to a high number of deaths, disabilities, and long-term consequences in patients. Russell's viper (Daboia russelii) is one of the most medically important snake species in India, which causes devastating pathological conditions characterised by a wide range of clinical manifestations. This broad spectrum of symptoms requires additional therapeutic interventions beyond the classical antivenom administration. Hence, positive outcomes for patients affected by SBE can be achieved with a better understanding of previous experiences describing clinical manifestations and various therapeutic interventions including for rare and underreported conditions. Here, we report an SBE victim who developed partial segmental thrombosis in the corpus cavernosum following Russell's viper envenomation and its diagnostic and treatment approaches. The patients received 180 ml of antivenom to resolve the abnormalities in their haematological parameters. Despite antivenom treatment, they developed severe pain in their genital region, and subsequent ultrasound and magnetic resonance imaging confirmed segmental thrombosis in the corpus cavernosum, which required supportive measures. The treatment using low molecular weight heparin, rivaroxaban and non-steroidal anti-inflammatory drugs resolved segmental thrombosis. In conclusion, this case report exemplifies the development of a rare segmental thrombosis in corpus cavernosum and how the medical, scientific, and general community can benefit from documenting clinical manifestations, medically relevant insights into patient care and the management of underreported complications.

18.
Front Psychol ; 14: 1110282, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37397324

RESUMO

Effective next-generation leadership is central to the multi-generational survival of family businesses. This study of 100 next-generation family business leaders found that business-owning families that openly express their opinions, take time to listen to each other, and squarely address difficult issues positively influence the development of the emotional and social intelligence competencies in next-generation family leaders that drive their leadership effectiveness. That kind of open and transparent communication in the family also makes it more likely next-generation leaders will be held accountable for their leadership performance by others, which increases the degree to which they are positively engaged with their work in the family firm. On the other hand, the results suggest that senior-generation family leaders who lead autocratically, a leadership style often observed in entrepreneurs who found family firms, make it less likely that next-generation family leaders will learn the emotional and social intelligence competencies that predict their leadership effectiveness. The study also found that autocratic senior-generation leaders negatively affect next-generation leader self-efficacy and make it less likely that others will hold them accountable, which limits their engagement with work in the family business. One of the study's most important findings is that next-generation leader acceptance of personal responsibility for their leadership behaviors and results serves as a mediator through which the nature of the family climate influences their leadership effectiveness and work engagement. This suggests that while the nature of family relationships may make it easier or more difficult, next-generation family leaders have ultimate control over the development of their leadership talent and the inspiration, enthusiasm, energy, and pride they feel when working in the family business.

19.
bioRxiv ; 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37425765

RESUMO

Firefly luciferase is homologous to fatty acyl-CoA synthetases from insects that are not bioluminescent. Here, we determined the crystal structure of the fruit fly fatty acyl-CoA synthetase CG6178 to 2.5 Å. Based on this structure, we mutated a steric protrusion in the active site to create the artificial luciferase FruitFire, which prefers the synthetic luciferin CycLuc2 to d-luciferin by >1000-fold. FruitFire enabled in vivo bioluminescence imaging in the brains of mice using the pro-luciferin CycLuc2-amide. The conversion of a fruit fly enzyme into a luciferase capable of in vivo imaging underscores the potential for bioluminescence with a range of adenylating enzymes from nonluminescent organisms, and the possibilities for application-focused design of enzyme-substrate pairs.

20.
Chem Commun (Camb) ; 59(55): 8552-8555, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37337906

RESUMO

Firefly luciferin methyl ester is hydrolyzed by monoacylglycerol lipase MAGL, amidase FAAH, poorly-characterized hydrolase ABHD11, and hydrolases known for S-depalmitoylation (LYPLA1/2), not just esterase CES1. This enables activity-based bioluminescent assays for serine hydrolases and suggests that the 'esterase activity' responsible for hydrolyzing ester prodrugs is more diverse than previously supposed.


Assuntos
Luciferina de Vaga-Lumes , Monoacilglicerol Lipases , Amidoidrolases , Serina , Inibidores Enzimáticos
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