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The developmental programs that generate a broad repertoire of regulatory T cells (Treg cells) able to respond to both self antigens and non-self antigens remain unclear. Here we found that mature Treg cells were generated through two distinct developmental programs involving CD25+ Treg cell progenitors (CD25+ TregP cells) and Foxp3lo Treg cell progenitors (Foxp3lo TregP cells). CD25+ TregP cells showed higher rates of apoptosis and interacted with thymic self antigens with higher affinity than did Foxp3lo TregP cells, and had a T cell antigen receptor repertoire and transcriptome distinct from that of Foxp3lo TregP cells. The development of both CD25+ TregP cells and Foxp3lo TregP cells was controlled by distinct signaling pathways and enhancers. Transcriptomics and histocytometric data suggested that CD25+ TregP cells and Foxp3lo TregP cells arose by coopting negative-selection programs and positive-selection programs, respectively. Treg cells derived from CD25+ TregP cells, but not those derived from Foxp3lo TregP cells, prevented experimental autoimmune encephalitis. Our findings indicate that Treg cells arise through two distinct developmental programs that are both required for a comprehensive Treg cell repertoire capable of establishing immunotolerance.
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Diferenciação Celular/imunologia , Encefalomielite Autoimune Experimental/imunologia , Células Progenitoras Linfoides/fisiologia , Linfócitos T Reguladores/fisiologia , Timo/crescimento & desenvolvimento , Animais , Autoantígenos/imunologia , Colite/imunologia , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Adjuvante de Freund/administração & dosagem , Adjuvante de Freund/imunologia , Humanos , Tolerância Imunológica/imunologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Células Progenitoras Linfoides/transplante , Camundongos , Camundongos Transgênicos , Mycobacterium tuberculosis/imunologia , Glicoproteína Mielina-Oligodendrócito/administração & dosagem , Glicoproteína Mielina-Oligodendrócito/imunologia , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/imunologia , Transdução de Sinais , Organismos Livres de Patógenos Específicos , Timo/citologia , Timo/imunologiaRESUMO
The senataxin (SETX, Sen1 in yeasts) RNA-DNA hybrid resolving helicase regulates multiple nuclear transactions, including DNA replication, transcription, and DNA repair, but the molecular basis for Sen1 activities is ill defined. Here, Sen1 cryoelectron microscopy (cryo-EM) reconstructions reveal an elongated inchworm-like architecture. Sen1 is composed of an amino terminal helical repeat Sen1 N-terminal (Sen1N) regulatory domain that is flexibly linked to its C-terminal SF1B helicase motor core (Sen1Hel) via an intrinsically disordered tether. In an autoinhibited state, the Sen1Sen1N domain regulates substrate engagement by promoting occlusion of the RNA substrate-binding cleft. The X-ray structure of an activated Sen1Hel engaging single-stranded RNA and ADP-SO4 shows that the enzyme encircles RNA and implicates a single-nucleotide power stroke in the Sen1 RNA translocation mechanism. Together, our data unveil dynamic protein-protein and protein-RNA interfaces underpinning helicase regulation and inactivation of human SETX activity by RNA-binding-deficient mutants in ataxia with oculomotor apraxia 2 neurodegenerative disease.
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Doenças Neurodegenerativas , RNA , Humanos , RNA/genética , Microscopia Crioeletrônica , RNA Helicases/genética , RNA Helicases/química , Enzimas Multifuncionais/genética , DNA/genética , Homeostase , DNA Helicases/genéticaRESUMO
The capability to reach ultracold atomic temperatures in compact instruments has recently been extended into space1,2. Ultracold temperatures amplify quantum effects, whereas free fall allows further cooling and longer interactions time with gravity-the final force without a quantum description. On Earth, these devices have produced macroscopic quantum phenomena such as Bose-Einstein condensates (BECs), superfluidity, and strongly interacting quantum gases3. Terrestrial quantum sensors interfering the superposition of two ultracold atomic isotopes have tested the universality of free fall (UFF), a core tenet of Einstein's classical gravitational theory, at the 10-12 level4. In space, cooling the elements needed to explore the rich physics of strong interactions or perform quantum tests of the UFF has remained elusive. Here, using upgraded hardware of the multiuser Cold Atom Lab (CAL) instrument aboard the International Space Station (ISS), we report, to our knowledge, the first simultaneous production of a dual-species BEC in space (formed from 87Rb and 41K), observation of interspecies interactions, as well as the production of 39K ultracold gases. Operating a single laser at a 'magic wavelength' at which Rabi rates of simultaneously applied Bragg pulses are equal, we have further achieved the first spaceborne demonstration of simultaneous atom interferometry with two atomic species (87Rb and 41K). These results are an important step towards quantum tests of UFF in space and will allow scientists to investigate aspects of few-body physics, quantum chemistry and fundamental physics in new regimes without the perturbing asymmetry of gravity.
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Quantum mechanics governs the microscopic world, where low mass and momentum reveal a natural wave-particle duality. Magnifying quantum behaviour to macroscopic scales is a major strength of the technique of cooling and trapping atomic gases, in which low momentum is engineered through extremely low temperatures. Advances in this field have achieved such precise control over atomic systems that gravity, often negligible when considering individual atoms, has emerged as a substantial obstacle. In particular, although weaker trapping fields would allow access to lower temperatures1,2, gravity empties atom traps that are too weak. Additionally, inertial sensors based on cold atoms could reach better sensitivities if the free-fall time of the atoms after release from the trap could be made longer3. Planetary orbit, specifically the condition of perpetual free-fall, offers to lift cold-atom studies beyond such terrestrial limitations. Here we report production of rubidium Bose-Einstein condensates (BECs) in an Earth-orbiting research laboratory, the Cold Atom Lab. We observe subnanokelvin BECs in weak trapping potentials with free-expansion times extending beyond one second, providing an initial demonstration of the advantages offered by a microgravity environment for cold-atom experiments and verifying the successful operation of this facility. With routine BEC production, continuing operations will support long-term investigations of trap topologies unique to microgravity4,5, atom-laser sources6, few-body physics7,8 and pathfinding techniques for atom-wave interferometry9-12.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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The replicative mitochondrial DNA polymerase, Polγ, and its protein regulation are essential for the integrity of the mitochondrial genome. The intricacies of Polγ regulation and its interactions with regulatory proteins, which are essential for fine-tuning polymerase function, remain poorly understood. Misregulation of the Polγ heterotrimer, consisting of (i) PolG, the polymerase catalytic subunit and (ii) PolG2, the accessory subunit, ultimately results in mitochondrial diseases. Here, we used single particle cryo-electron microscopy to resolve the structure of PolG in its apoprotein state and we captured Polγ at three intermediates within the catalytic cycle: DNA bound, engaged, and an active polymerization state. Chemical crosslinking mass spectrometry, and site-directed mutagenesis uncovered the region of LonP1 engagement of PolG, which promoted proteolysis and regulation of PolG protein levels. PolG2 clinical variants, which disrupted a stable Polγ complex, led to enhanced LonP1-mediated PolG degradation. Overall, this insight into Polγ aids in an understanding of mitochondrial DNA replication and characterizes how machinery of the replication fork may be targeted for proteolytic degradation when improperly functioning.
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DNA Polimerase gama , Replicação do DNA , DNA Mitocondrial , Proteínas Mitocondriais , Polimerização , Proteólise , DNA Polimerase gama/metabolismo , DNA Polimerase gama/genética , Humanos , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/química , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/genética , DNA Polimerase Dirigida por DNA/química , Proteases Dependentes de ATP/metabolismo , Proteases Dependentes de ATP/genéticaRESUMO
CyVerse, the largest publicly-funded open-source research cyberinfrastructure for life sciences, has played a crucial role in advancing data-driven research since the 2010s. As the technology landscape evolved with the emergence of cloud computing platforms, machine learning and artificial intelligence (AI) applications, CyVerse has enabled access by providing interfaces, Software as a Service (SaaS), and cloud-native Infrastructure as Code (IaC) to leverage new technologies. CyVerse services enable researchers to integrate institutional and private computational resources, custom software, perform analyses, and publish data in accordance with open science principles. Over the past 13 years, CyVerse has registered more than 124,000 verified accounts from 160 countries and was used for over 1,600 peer-reviewed publications. Since 2011, 45,000 students and researchers have been trained to use CyVerse. The platform has been replicated and deployed in three countries outside the US, with additional private deployments on commercial clouds for US government agencies and multinational corporations. In this manuscript, we present a strategic blueprint for creating and managing SaaS cyberinfrastructure and IaC as free and open-source software.
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Inteligência Artificial , Software , Humanos , Computação em Nuvem , EditoraçãoRESUMO
Twinkle is the mammalian helicase vital for replication and integrity of mitochondrial DNA. Over 90 Twinkle helicase disease variants have been linked to progressive external ophthalmoplegia and ataxia neuropathies among other mitochondrial diseases. Despite the biological and clinical importance, Twinkle represents the only remaining component of the human minimal mitochondrial replisome that has yet to be structurally characterized. Here, we present 3-dimensional structures of human Twinkle W315L. Employing cryo-electron microscopy (cryo-EM), we characterize the oligomeric assemblies of human full-length Twinkle W315L, define its multimeric interface, and map clinical variants associated with Twinkle in inherited mitochondrial disease. Cryo-EM, crosslinking-mass spectrometry, and molecular dynamics simulations provide insight into the dynamic movement and molecular consequences of the W315L clinical variant. Collectively, this ensemble of structures outlines a framework for studying Twinkle function in mitochondrial DNA replication and associated disease states.
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Microscopia Crioeletrônica , DNA Helicases , Doenças Mitocondriais , Proteínas Mitocondriais , Multimerização Proteica , DNA Helicases/química , DNA Helicases/genética , DNA Helicases/metabolismo , DNA Helicases/ultraestrutura , Replicação do DNA , DNA Mitocondrial/biossíntese , Humanos , Espectrometria de Massas , Doenças Mitocondriais/genética , Proteínas Mitocondriais/química , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/ultraestrutura , Simulação de Dinâmica Molecular , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Proteínas Mutantes/ultraestruturaRESUMO
In Saccharomyces cerevisiae, the transcriptional repressor Opi1 regulates the expression of genes involved in phospholipid synthesis responding to the abundance of the phospholipid precursor phosphatidic acid at the endoplasmic reticulum. We report here the identification of the conserved leucine zipper (LZ) domain of Opi1 as a hot spot for gain of function mutations and the characterization of the strongest variant identified, Opi1N150D. LZ modeling posits asparagine 150 embedded on the hydrophobic surface of the zipper and specifying dynamic parallel homodimerization by allowing electrostatic bonding across the hydrophobic dimerization interface. Opi1 variants carrying any of the other three ionic residues at amino acid 150 were also repressing. Genetic analyses showed that Opi1N150D variant is dominant, and its phenotype is attenuated when loss of function mutations identified in the other two conserved domains are present in cis. We build on the notion that membrane binding facilitates LZ dimerization to antagonize an intramolecular interaction of the zipper necessary for repression. Dissecting Opi1 protein in three polypeptides containing each conserved region, we performed in vitro analyses to explore interdomain interactions. An Opi11-190 probe interacted with Opi1291-404, the C terminus that bears the activator interacting domain (AID). LZ or AID loss of function mutations attenuated the interaction of the probes but was unaffected by the N150D mutation. We propose a model for Opi1 signal transduction whereby synergy between membrane-binding events and LZ dimerization antagonizes intramolecular LZ-AID interaction and transcriptional repression.
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Zíper de Leucina , Fosfolipídeos , Proteínas Repressoras , Proteínas de Saccharomyces cerevisiae , Fosfolipídeos/biossíntese , Proteínas Repressoras/química , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais , Multimerização ProteicaRESUMO
"Cases of SCMR" is a case series on the SCMR website (https://www.scmr.org) for the purpose of education. The cases reflect the clinical presentation, and the use of cardiovascular magnetic resonance (CMR) in the diagnosis and management of cardiovascular disease. The 2022 digital collection of cases are presented in this manuscript.
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Doenças Cardiovasculares , Valor Preditivo dos Testes , Humanos , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/terapia , Pessoa de Meia-Idade , Feminino , Masculino , Idoso , Imageamento por Ressonância Magnética , Adulto , Prognóstico , Adulto JovemRESUMO
OBJECTIVE: The objective of this study was to describe feeding practices and weight status in a cohort of children with congenital Zika syndrome (CZS) in northeastern Brazil. METHODS: This longitudinal study of children with CZS (N = 156) included data collection on child feeding practices and weight status at five timepoints between 2018 and 2022. The average age of the children was 32.1 months at enrollment and 76.6 months at the fifth assessment. Multilevel models, with repeated observations nested within children, were used to estimate time-related differences in each outcome. RESULTS: Use of enteral feeding, such as gastrostomy, increased from 19.2% to 33.3% over 4 years (p < .001). Among children who did not exclusively use an enteral feeding method, the percentage experiencing at least one dysphagia-associated behavior, such as coughing or gagging, increased from 73.9% to 85.3% (p = .030) while consuming liquids and from 36.2% to 73.5% (p = .001) while consuming solids. Based on weight-for-age z-scores, the percentage of children who were moderately or severely underweight increased from 42.5% to 46.1% over the 4 years but was not statistically significant. Children exclusively using an enteral feeding method had significantly decreased odds of being underweight at assessments 3, 4, and 5. CONCLUSIONS: These data highlight the ongoing and increasing challenges of feeding young children with CZS. Our findings elucidate the physiological reasons children with CZS may be underweight and point to intervention targets, such as enteral feeding, to improve their feeding practices.
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BACKGROUND: Cardiovascular disease (CVD) remains a leading cause of death in people living with HIV. Myocardial fibrosis is well-described in HIV infection acquired in adulthood. We evaluate the burden of fibrosis by cardiac magnetic resonance in people with perinatal HIV infection. METHODS: Individuals with perinatally acquired HIV (pnHIV) diagnosed before 10 years-old and on antiretroviral treatment for ≥ 6 months were matched with uninfected controls. Patients with significant cardiometabolic co-morbidities and pregnancy were excluded. Diffuse fibrosis was assessed by cardiac magnetic resonance (CMR) with native T1 mapping for calculation of extracellular volume fraction (ECV). Viability was assessed with late gadolinium enhancement. The normality of fibrosis was assessed using the Komogrov-Smirnov test. Fibrosis between the groups was analyzed using a Mann-Whitney U test, as the data was not normally distributed. Statistical significance was defined as a p-valve < 0.05. RESULTS: Fourteen adults with pnHIV group and 26 controls (71% female and 86% Black race) were assessed. The average (± standard deviation) age in the study group was 29 (± 4.3) years-old. All pnHIV had been on ART for decades. Demographic data, CMR functional/volumetric data, and pre-contrast T1 mapping values were similar between groups. Diastolic function was normal in 50% of pnHIV patients and indeterminate in most of the remainder (42%). There was no statistically significant difference in ECV between groups; p = 0.24. CONCLUSION: Perinatally-acquired HIV was not associated with diffuse myocardial fibrosis. Larger prospective studies with serial examinations are needed to determine whether pnHIV patients develop abnormal structure or function more often than unaffected controls.
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Infecções por HIV , Adulto , Gravidez , Humanos , Feminino , Adulto Jovem , Criança , Masculino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Meios de Contraste , Estudos Prospectivos , Gadolínio , FibroseRESUMO
BACKGROUND: Mixed pulmonary disease with pulmonary regurgitation (PR) and stenosis (PS) in repaired tetralogy of Fallot (rTOF) can negatively impact ventricular health. Myocardial strain has been shown to be more sensitive at detecting occult ventricular dysfunction compared to right ventricular ejection fraction (RV EF). We hypothesize that rTOF patients with predominant PS will have lower RV global longitudinal strain (RV GLS) prior to and post-transcatheter pulmonary valve replacement (TPVR). METHODS: A retrospective cohort of rTOF patients who underwent cardiac magnetic resonance (CMR) and cardiac catheterization for right ventricular pressure (RVSP) measurement were analyzed at three time points: before valve implantation, at discharge and within 18 months post-TPVR. Patients were dichotomized into three groups based on RVSP: 0%-49%, 50%-74%, and >75%. RV GLS and left ventricular (LV) GLS by speckle tracking echocardiography (STE) were obtained from the apical 4-chamber using TomTec software (TOMTEC IS, Germany). RESULTS: Forty-eight patients were included. Every 14.3% increase in preimplantation RVSP above 28% was associated with an absolute magnitude 1% lower RV GLS (p = .001). Preimplantation RVSP when 75% or higher had 3.36% worse RV GLS than the lowest bin (p = .014). Overall, average RV strain magnitude was higher when preimplantation RVSP was less than 50% and had greater improvement over the three time points. Higher post implantation RVSP correlated with lower strain magnitude. CONCLUSION: Patients with significant PS (>50%) may benefit from earlier PVR and not depend solely on RV size and EF. Myocardial strain may be a more sensitive marker of function; however, larger, prospective studies are needed.
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Insuficiência da Valva Pulmonar , Estenose da Valva Pulmonar , Valva Pulmonar , Tetralogia de Fallot , Disfunção Ventricular Direita , Humanos , Tetralogia de Fallot/complicações , Tetralogia de Fallot/cirurgia , Deformação Longitudinal Global , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/cirurgia , Volume Sistólico , Estudos Retrospectivos , Função Ventricular Direita , Estenose da Valva Pulmonar/complicações , Estenose da Valva Pulmonar/cirurgia , Insuficiência da Valva Pulmonar/complicações , Insuficiência da Valva Pulmonar/diagnóstico por imagem , Insuficiência da Valva Pulmonar/cirurgia , Disfunção Ventricular Direita/complicações , Disfunção Ventricular Direita/diagnóstico por imagemRESUMO
Adults with congenital heart disease (CHD) benefit from cardiology follow-up at recommended intervals of ≤ 2 years. However, benefit for children is less clear given limited studies and unclear current guidelines. We hypothesize there are identifiable risks for gaps in cardiology follow-up in children with CHD and that gaps in follow-up are associated with differences in healthcare utilization. Our cohort included children < 10 years old with CHD and a healthcare encounter from 2008 to 2013 at one of four North Carolina (NC) hospitals. We assessed associations between cardiology follow-up and demographics, lesion severity, healthcare access, and educational isolation (EI). We compared healthcare utilization based on follow-up. Overall, 60.4% of 6,969 children received cardiology follow-up within 2 years of initial encounter, including 53.1%, 58.1%, and 79.0% of those with valve, shunt, and severe lesions, respectively. Factors associated with gaps in care included increased drive time to a cardiology clinic (Hazard Ratio (HR) 0.92/15-min increase), EI (HR 0.94/0.2-unit increase), lesion severity (HR 0.48 for shunt/valve vs severe), and older age (HR 0.95/month if < 1 year old and 0.94/year if > 1 year old; p < 0.05). Children with a care gap subsequently had more emergency department (ED) visits (Rate Ratio (RR) 1.59) and fewer inpatient encounters and procedures (RR 0.51, 0.35; p < 0.05). We found novel factors associated with gaps in care for cardiology follow-up in children with CHD and altered health care utilization with a gap. Our findings demonstrate a need to mitigate healthcare barriers and generate clear cardiology follow-up guidelines for children with CHD.
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Cardiopatias Congênitas , Humanos , Cardiopatias Congênitas/terapia , Masculino , Feminino , Pré-Escolar , Fatores de Risco , Lactente , Criança , North Carolina/epidemiologia , Acessibilidade aos Serviços de Saúde , Estudos Retrospectivos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Recém-Nascido , SeguimentosRESUMO
OBJECTIVE: Identifying thrombus formation in Fontan circulation has been highly variable, with reports between 17 and 33%. Initially, thrombus detection was mainly done through echocardiograms. Delayed-enhancement cardiac MRI is emerging as a more effective imaging technique for thrombus identification. This study aims to determine the prevalence of occult cardiac thrombosis in patients undergoing clinically indicated cardiac MRI. METHODS: A retrospective chart review of children and adults in the Duke University Hospital Fontan registry who underwent delayed-enhancement cardiac MRI. Individuals were excluded if they never received a delayed-enhancement cardiac MRI or had insufficient data. Demographic characteristics, native heart anatomy, cardiac MRI measurements, and thromboembolic events were collected for all patients. RESULTS: In total, 119 unique individuals met inclusion criteria with a total of 171 scans. The median age at Fontan procedure was 3 (interquartile range 1, 4) years. The majority of patients had dominant systemic right ventricle. Cardiac function was relatively unchanged from the first cardiac MRI to the third cardiac MRI. While 36.4% had a thrombotic event by history, only 0.5% (1 patient) had an intracardiac thrombus detected by delayed-enhancement cardiac MRI. CONCLUSIONS: Despite previous echocardiographic reports of high prevalence of occult thrombosis in patients with Fontan circulation, we found very low prevalence using delayed-enhancement cardiac MRI. As more individuals are reaching adulthood after requiring early Fontan procedures in childhood, further work is needed to develop thrombus-screening protocols as a part of anticoagulation management.
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BACKGROUND: Despite a trend towards combining abdominoplasty with breast reduction surgery, so called "mommy makeovers", the safety of this combined approach has been the subject of debate, with previous research yielding conflicting results. We evaluated the risk for complications and revision associated with adding abdominoplasty to bilateral breast reduction surgery. METHODS: We conducted a 10-year single-center retrospective chart review of bilateral breast reduction patients in Nova Scotia. Univariate and multivariate analyses were performed to compare the risk for complication and revision in patients with bilateral breast reduction to those with a concomitant abdominoplasty. RESULTS: Of the 1871 patients initially screened, 738 were included. 44 underwent a concomitant abdominoplasty procedure. Compared to the breast reduction alone group, patients with concomitant abdominoplasty were significantly older (47.5±9.9 vs. 42.8±13.2, p=0.004), had a higher BMI (28.1±4.4 vs. 25.8±3.1, p<0.001), and experienced longer operating room times (226±6 vs. 115±3 mins, p<0.001). In multivariate analysis, concomitant abdominoplasty did not increase the risk for breast-related (OR: 0.86 95%CI 0.43-1.7, p=0.668) or total complications (OR: 1.63, 95%CI 0.83-3.19, p=0.154). However, there was a trend towards an increased risk of breast revision (OR: 2.684, 95%CI 0.95-7.6, p=0.062) and a significantly increased risk of total revision (OR: 6.624, 95%CI 2.7-16.1, p<0.001). Moreover, patients with concomitant abdominoplasty experienced more follow-up visits (median: 4 vs. 3 visits, p=0.042). CONCLUSION: In our single-center retrospective analysis, combining abdominoplasty with bilateral breast reduction did not increase the risk for breast, or total complications; however, it did increase the risk for total revisions. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
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The Wilderness Medical Society reconvened an expert panel to update best practice guidelines for spinal cord protection during trauma management. This panel, with membership updated in 2023, was charged with the development of evidence-based guidelines for management of the injured or potentially injured spine in wilderness environments. Recommendations are made regarding several parameters related to spinal cord protection. These recommendations are graded based on the quality of supporting evidence and balance the benefits and risks/burdens for each parameter according to American College of Chest Physicians methodology. Key recommendations include the concept that interventions should be goal-oriented (spinal cord/column protection in the context of overall patient and provider safety) rather than technique-oriented (immobilization). An evidence-based, goal-oriented approach excludes the immobilization of suspected spinal injuries via rigid collars or backboards.
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Medula Espinal , Medicina Selvagem , Humanos , Sociedades MédicasRESUMO
BACKGROUND: The perception of an ideal nose is influenced by a variety of factors, with demographic characteristics playing a significant role in what is considered an ideal nose. The nasolabial angle (NLA) is considered one of the defining features shaping the nose. OBJECTIVES: In this study we set out to capture the perception of the ideal nasolabial angle among Canadian, Saudi, Kuwaiti, and Lebanese populations. METHODS: An online questionnaire-based cross-sectional study was conducted to investigate the ideal nasolabial angle among Canadian, Saudi, Kuwaiti, and Lebanese populations (n = 197). Participants were patients attending outpatient clinics, plastic surgery residents, and medical students. The questionnaire included demographics and the perception of respondents of the ideal NLA for each gender: male (85°, 90°, 95°, 100°, 110°) and females (95°, 100°, 110°, 115°). RESULTS: The majority of respondents were female (81.2%), ages between 20 and 39 (84.3%). The mean and standard deviation of ideal NLA choices in both male and female models were 97.1 ± 6.39 and 109.5 ± 5.32, respectively. The ideal male NLA choices were found to correlate significantly with age (P = .044) and work status (P = .019). In choosing the ideal female NLA, age was a significant factor (P = .012). CONCLUSIONS: Identifying the ideal NLA is essential to establishing aesthetic goals for patient and surgeon alike. It is important to understand the effects of demographics on the choice of the ideal NLA, which ultimately influences the planning and outcome of the rhinoplasty procedure.
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Rinoplastia , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Rinoplastia/métodos , Estudos Transversais , Canadá , Nariz/cirurgia , Inquéritos e QuestionáriosRESUMO
Right ventricular (RV) failure is the major determinant of outcome in pulmonary hypertension (PH). Calves exposed to 2-wk hypoxia develop severe PH and unlike rodents, hypoxia-induced PH in this species can lead to right heart failure. We, therefore, sought to examine the molecular and structural changes in the RV in calves with hypoxia-induced PH, hypothesizing that we could identify mechanisms underlying compensated physiological function in the face of developing severe PH. Calves were exposed to 14 days of environmental hypoxia (equivalent to 4,570 m/15,000 ft elevation, n = 29) or ambient normoxia (1,525 m/5,000 ft, n = 25). Cardiopulmonary function was evaluated by right heart catheterization and pressure volume loops. Molecular and cellular determinants of RV remodeling were analyzed by cDNA microarrays, RealTime PCR, proteomics, and immunochemistry. Hypoxic exposure induced robust PH, with increased RV contractile performance and preserved cardiac output, yet evidence of dysregulated RV-pulmonary artery mechanical coupling as seen in advanced disease. Analysis of gene expression revealed cellular processes associated with structural remodeling, cell signaling, and survival. We further identified specific clusters of gene expression associated with 1) hypertrophic gene expression and prosurvival mechanotransduction through YAP-TAZ signaling, 2) extracellular matrix (ECM) remodeling, 3) inflammatory cell activation, and 4) angiogenesis. A potential transcriptomic signature of cardiac fibroblasts in RV remodeling was detected, enriched in functions related to cell movement, tissue differentiation, and angiogenesis. Proteomic and immunohistochemical analysis confirmed RV myocyte hypertrophy, together with localization of ECM remodeling, inflammatory cell activation, and endothelial cell proliferation within the RV interstitium. In conclusion, hypoxia and hemodynamic load initiate coordinated processes of protective and compensatory RV remodeling to withstand the progression of PH.NEW & NOTEWORTHY Using a large animal model and employing a comprehensive approach integrating hemodynamic, transcriptomic, proteomic, and immunohistochemical analyses, we examined the early (2 wk) effects of severe PH on the RV. We observed that RV remodeling during PH progression represents a continuum of transcriptionally driven processes whereby cardiac myocytes, fibroblasts, endothelial cells, and proremodeling macrophages act to coordinately maintain physiological homeostasis and protect myocyte survival during chronic, severe, and progressive pressure overload.
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Insuficiência Cardíaca , Hipertensão Pulmonar , Disfunção Ventricular Direita , Animais , Bovinos , Hipertensão Pulmonar/metabolismo , Células Endoteliais/metabolismo , Mecanotransdução Celular , Proteômica , Hipertrofia Ventricular Direita/genética , Hipertrofia Ventricular Direita/metabolismo , Ventrículos do Coração , Modelos Animais de Doenças , Hipóxia , Remodelação Ventricular , Função Ventricular Direita , Disfunção Ventricular Direita/genética , Disfunção Ventricular Direita/complicaçõesRESUMO
A method for the generation and reaction of carbamoyl radicals from oxamate salts, followed by reaction with electron-poor olefins, is described. The oxamate salt acts as a reductive quencher in the photoredox catalytic cycle, allowing mild and mass-efficient formation of 1,4-dicarbonyl products; a challenging transformation in the context of functionalized amide formation. Increased understanding has been obtained by the use of ab initio calculations, in support of experimental observations. Furthermore, steps have been taken towards an environmentally-friendly protocol, by utilizing sodium as a cheap and low mass counterion, and demonstrating successful reactions using a metal-free photocatalyst and a sustainable, non-toxic solvent system.