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1.
Crit Care Med ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578158

RESUMO

OBJECTIVES: Quantify the relationship between perioperative anaerobic lactate production, microcirculatory blood flow, and mitochondrial respiration in patients after cardiovascular surgery with cardiopulmonary bypass. DESIGN: Serial measurements of lactate-pyruvate ratio (LPR), microcirculatory blood flow, plasma tricarboxylic acid cycle cycle intermediates, and mitochondrial respiration were compared between patients with a normal peak lactate (≤ 2 mmol/L) and a high peak lactate (≥ 4 mmol/L) in the first 6 hours after surgery. Regression analysis was performed to quantify the relationship between clinically relevant hemodynamic variables, lactate, LPR, and microcirculatory blood flow. SETTING: This was a single-center, prospective observational study conducted in an academic cardiovascular ICU. PATIENTS: One hundred thirty-two patients undergoing elective cardiovascular surgery with cardiopulmonary bypass. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients with a high postoperative lactate were found to have a higher LPR compared with patients with a normal postoperative lactate (14.4 ± 2.5 vs. 11.7 ± 3.4; p = 0.005). Linear regression analysis found a significant, negative relationship between LPR and microcirculatory flow index (r = -0.225; ß = -0.037; p = 0.001 and proportion of perfused vessels: r = -0.17; ß = -0.468; p = 0.009). There was not a significant relationship between absolute plasma lactate and microcirculation variables. Last, mitochondrial complex I and complex II oxidative phosphorylation were reduced in patients with high postoperative lactate levels compared with patients with normal lactate (22.6 ± 6.2 vs. 14.5 ± 7.4 pmol O2/s/106 cells; p = 0.002). CONCLUSIONS: Increased anaerobic lactate production, estimated by LPR, has a negative relationship with microcirculatory blood flow after cardiovascular surgery. This relationship does not persist when measuring lactate alone. In addition, decreased mitochondrial respiration is associated with increased lactate after cardiovascular surgery. These findings suggest that high lactate levels after cardiovascular surgery, even in the setting of normal hemodynamics, are not simply a type B phenomenon as previously suggested.

2.
J Gastrointest Surg ; 28(4): 507-512, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38583903

RESUMO

BACKGROUND: The risk of recurrence is an important consideration when deciding to treat patients medically or with elective colectomy after recovery from diverticulitis. It is unclear whether age is associated with recurrence. This study aimed to examine the relationship between age and the risk of recurrent diverticulitis while considering important epidemiologic factors, such as birth decade. METHODS: The Utah Population Database was used to identify individuals with incident severe diverticulitis, defined as requiring an emergency department visit or hospitalization, between 1998 and 2018. This study measured the relationship between age and recurrent severe diverticulitis after adjusting for birth decade and other important variables, such as sex, urban/rural status, complicated diverticulitis, and body mass index using a Cox proportional hazards model. RESULTS: The cohort included 8606 individuals with a median age of 61 years at index diverticulitis diagnosis. After adjustment, among individuals born in the same birth decade, increasing age at diverticulitis onset was associated with an increased risk of recurrent diverticulitis (hazard ratio [HR] for 10 years, 1.8; 95% CI, 1.5-2.1). Among individuals with the same age of onset, those born in a more recent birth decade were also at greater risk of recurrent diverticulitis (HR, 1.9; 95% CI, 1.6-2.3). CONCLUSION: Among individuals with an index episode of severe diverticulitis, recurrence was associated with increasing age and more recent birth decade. Clinicians may wish to employ age-specific strategies when counseling patients regarding treatment options after a diverticulitis diagnosis.


Assuntos
Doença Diverticular do Colo , Diverticulite , Humanos , Pessoa de Meia-Idade , Criança , Doença Diverticular do Colo/epidemiologia , Doença Diverticular do Colo/cirurgia , Doença Diverticular do Colo/complicações , Estudos Retrospectivos , Diverticulite/complicações , Hospitalização , Colectomia/efeitos adversos , Recidiva
3.
Front Immunol ; 15: 1347542, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558815

RESUMO

Background: Neoantigens, mutated tumour-specific antigens, are key targets of anti-tumour immunity during checkpoint inhibitor (CPI) treatment. Their identification is fundamental to designing neoantigen-directed therapy. Non-canonical neoantigens arising from the untranslated regions (UTR) of the genome are an overlooked source of immunogenic neoantigens. Here, we describe the landscape of UTR-derived neoantigens and release a computational tool, PrimeCUTR, to predict UTR neoantigens generated by start-gain and stop-loss mutations. Methods: We applied PrimeCUTR to a whole genome sequencing dataset of pre-treatment tumour samples from CPI-treated patients (n = 341). Cancer immunopeptidomic datasets were interrogated to identify MHC class I presentation of UTR neoantigens. Results: Start-gain neoantigens were predicted in 72.7% of patients, while stop-loss mutations were found in 19.3% of patients. While UTR neoantigens only accounted 2.6% of total predicted neoantigen burden, they contributed 12.4% of neoantigens with high dissimilarity to self-proteome. More start-gain neoantigens were found in CPI responders, but this relationship was not significant when correcting for tumour mutational burden. While most UTR neoantigens are private, we identified two recurrent start-gain mutations in melanoma. Using immunopeptidomic datasets, we identify two distinct MHC class I-presented UTR neoantigens: one from a recurrent start-gain mutation in melanoma, and one private to Jurkat cells. Conclusion: PrimeCUTR is a novel tool which complements existing neoantigen discovery approaches and has potential to increase the detection yield of neoantigens in personalised therapeutics, particularly for neoantigens with high dissimilarity to self. Further studies are warranted to confirm the expression and immunogenicity of UTR neoantigens.


Assuntos
Melanoma , Humanos , Antígenos de Neoplasias/genética , Genes MHC Classe I , Mutação , Imunoterapia
4.
Pediatr Res ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565916

RESUMO

BACKGROUND: Infants with single ventricle heart disease (SVHD) suffer morbidity from insufficient pulmonary blood flow, which may be related to impaired arginine metabolism. No prior study has reported quantitative mapping of arginine metabolites to evaluate the relationship between circulating metabolite levels and outcomes. METHODS: Prospective cohort study of 75 SVHD cases peri-Stage 2 and 50 healthy controls. We targeted pre- and post-op absolute serum quantification of 9 key members of the arginine metabolism pathway by tandem mass spectrometry. Primary outcomes were length of stay (LOS) and post-Stage 2 hypoxemia. RESULTS: Pre-op cases showed alteration in 6 metabolites including decreased arginine and increased asymmetric dimethyl arginine (ADMA) levels compared to controls. Post-op cases demonstrated decreased arginine and citrulline levels persisting through 48 h. Adjusting for clinical variables, lower pre-op and 2 h post-op concentrations of multiple metabolites, including arginine and citrulline, were associated with longer post-op LOS (p < 0.01). Increased ADMA at 24 h was associated with greater post-op hypoxemia burden (p < 0.05). CONCLUSION: Arginine metabolism is impaired in interstage SVHD infants and is further deranged following Stage 2 palliation. Patients with greater metabolite alterations experience greater post-op morbidity. Decreased arginine metabolism may be an important driver of pathology in SVHD. IMPACT: Interstage infants with SVHD have significantly altered arginine-nitric oxide metabolism compared to healthy children with deficiency of multiple pathway intermediates persisting through 48 h post-Stage 2 palliation. After controlling for clinical covariates and classic catheterization-derived predictors of Stage 2 readiness, both lower pre-operation and lower post-operation circulating metabolite levels were associated with longer post-Stage 2 LOS while increased post-Stage 2 ADMA concentration was associated with greater post-op hypoxemia. Arginine metabolism mapping offers potential for development using personalized medicine strategies as a biomarker of Stage 2 readiness and therapeutic target to improve pulmonary vascular health in infants with SVHD.

6.
Zebrafish ; 21(2): 181-190, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38621218

RESUMO

Fipronil is a broad-spectrum insecticide that has off-target effects in developing vertebrate embryos. In this study, we investigate treatment of zebrafish embryos with fipronil over the course of 5 days and examine the effects on body length, the cardiovascular system, and craniofacial morphology. We found the insecticide caused shorter body length and a decrease in eye size. By examining specific heart chamber morphology, as well as jaw angle and length, we quantified defects including enlargement of the heart and increases in jaw length and width. Further studies are needed to assess the mechanisms of fipronil's effect on vertebrate development for both environmental and human health concerns.


Assuntos
Inseticidas , Poluentes Químicos da Água , Animais , Humanos , Peixe-Zebra , Inseticidas/toxicidade , Embrião não Mamífero , Pirazóis/toxicidade
7.
Chem Sci ; 15(14): 5152-5162, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38577349

RESUMO

Coupling of octahedral, terminal d1 molybdenum(v) nitrido complexes supported by a dianionic pentadentate ligand via N-N bond formation to give µ-dinitrogen complexes was found to be thermodynamically feasible but faces significant kinetic barriers. However, upon oxidation, a kinetically favored nucleophilic/electrophilic N-N bond forming mechanism was enabled to give monocationic µ-dinitrogen dimers. Computational and experimental evidence for this "oxidation-induced ambiphilic nitrido coupling" mechanism is presented. The factors influencing release of dinitrogen from the resulting µ-dinitrogen dimers were also probed and it was found that further oxidation to a dicationic species is required to induce (very rapid) loss of dinitrogen. The mechanistic path discovered for N-N bond formation and dinitrogen release follows an ECECC sequence (E = "electrochemical step"; C = "chemical step"). Experimental evidence for the intermediacy of a highly electrophilic, cationic d0 molybdenum(vi) nitrido in the N-N bond forming mechanism via trapping with an isonitrile reagent is also discussed. Together these results are relevant to the development of molecular catalysts capable of mediating ammonia oxidation to dihydrogen and dinitrogen.

8.
Cell Stem Cell ; 31(4): 537-553.e5, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38579684

RESUMO

In polycystic kidney disease (PKD), microscopic tubules expand into macroscopic cysts. Among the world's most common genetic disorders, PKD is inherited via heterozygous loss-of-function mutations but is theorized to require additional loss of function. To test this, we establish human pluripotent stem cells in allelic series representing four common nonsense mutations, using CRISPR base editing. When differentiated into kidney organoids, homozygous mutants spontaneously form cysts, whereas heterozygous mutants (original or base corrected) express no phenotype. Using these, we identify eukaryotic ribosomal selective glycosides (ERSGs) as PKD therapeutics enabling ribosomal readthrough of these same nonsense mutations. Two different ERSGs not only prevent cyst initiation but also limit growth of pre-formed cysts by partially restoring polycystin expression. Furthermore, glycosides accumulate in cyst epithelia in organoids and mice. Our findings define the human polycystin threshold as a surmountable drug target for pharmacological or gene therapy interventions, with relevance for understanding disease mechanisms and future clinical trials.


Assuntos
Cistos , Doenças Renais Policísticas , Humanos , Camundongos , Animais , Códon sem Sentido/metabolismo , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo , Doenças Renais Policísticas/genética , Doenças Renais Policísticas/terapia , Doenças Renais Policísticas/metabolismo , Rim/metabolismo , Organoides/metabolismo , Cistos/genética , Cistos/metabolismo , Glicosídeos/metabolismo
9.
J Am Soc Nephrol ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652562

RESUMO

In response to decreasing numbers of individuals entering into nephrology fellowships, the American Society of Nephrology launched Kidney TREKS (Tutored Research and Education for Kidney Scholars) to stimulate interest in nephrology among medical students, graduate students, and postdoctoral fellows. The program combines a one-week intensive exposure to kidney physiology with a longitudinal mentorship program at the participants' home institutions. Ten years in, an analysis was conducted to assess its effectiveness. We surveyed participants to assess their opinions regarding nephrology before and after the course and followed them longitudinally to determine their career choices. TREKS applicants who were not selected to participate were used as a comparison group. 381 people participated in the program and 242 completed the survey. After TREKS, both medical students and graduate students showed increased interest in nephrology, with rank scores of 5.6±0.2 pre- to 7.5±0.1 post-course for medical students (mean ± standard deviation, n=189, p=0.001) and 7.3±0.3 to 8.7±0.3 (n=53, p=0.001) for graduate students. In long term follow-up, TREKS medical students chose a nephrology pipeline residency at a higher rate than medical students overall (57% vs. 31%, p=0.01) and TREKS applicants who did not participate (47% vs. 31%, p=0.04). Nephrology fellowship rates for these groups exceeded the general population but did not significantly differ between TREKS participants and applicants. PhD students and postdoctoral TREKS participants had a higher rate of participating in nephrology research compared to TREKS applicants (66% vs. 30%, p=0.01). In summary, the ASN Kidney TREKS program has demonstrated that it can improve interest in nephrology in the short term and increase the number of individuals going into nephrology careers. This long-term effect is most evident in PhD students and postdoctoral participants. Further study is needed to assess the impact of TREKS on enrollment in nephrology fellowship programs.

10.
bioRxiv ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38586057

RESUMO

Resting state functional MRI (rs-fMRI) is a popular and widely used technique to explore the brain's functional organization and to examine if it is altered in neurological or mental disorders. The most common approach for its analysis targets the measurement of the synchronized fluctuations between brain regions, characterized as functional connectivity (FC), typically relying on pairwise correlations in activity across different brain regions. While hugely successful in exploring state- and disease-dependent network alterations, these statistical graph theory tools suffer from two key limitations. First, they discard useful information about the rich frequency content of the fMRI signal. The rich spectral information now achievable from advances in fast multiband acquisitions is consequently being under-utilized. Second, the analyzed FCs are phenomenological without a direct neurobiological underpinning in the underlying structures and processes in the brain. There does not currently exist a complete generative model framework for whole brain resting fMRI that is informed by its underlying biological basis in the structural connectome. Here we propose that a different approach can solve both challenges at once: the use of an appropriately realistic yet parsimonious biophysical signal generation model followed by graph spectral (i.e. eigen) decomposition. We call this model a Spectral Graph Model (SGM) for fMRI, using which we can not only quantify the structure-function relationship in individual subjects, but also condense the variable and individual-specific repertoire of fMRI signal's spectral and spatial features into a small number of biophysically-interpretable parameters. We expect this model-based inference of rs-fMRI that seamlessly integrates with structure can be used to examine state and trait characteristics of structure-function relations in a variety of brain disorders.

11.
PLoS One ; 19(4): e0298464, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38630652

RESUMO

The global population consumes more seafood from aquaculture today than from capture fisheries and although the aquaculture industry continues to grow, both seafood sectors will continue to be important to the global food supply into the future. As farming continues to expand into ocean systems, understanding how wild populations and fisheries will interact with farms will be increasingly important to informing sustainable ocean planning and management. Using a spatially explicit population and fishing model we simulate several impacts from ocean aquaculture (i.e., aggregation, protection from fishing, and impacts on fitness) to evaluate the mechanisms underlying interactions between aquaculture, wild populations and fisheries. We find that aggregation of species to farms can increase the benefits of protection from fishing that a farm provides and can have greater impacts on more mobile species. Splitting total farm area into smaller farms can benefit fishery catches, whereas larger farms can provide greater ecological benefits through conservation of wild populations. Our results provide clear lessons on how to design and co-manage expanding ocean aquaculture along with wild capture ecosystem management to benefit fisheries or conservation objectives.


Assuntos
Ecossistema , Pesqueiros , Animais , Aquicultura/métodos , Abastecimento de Alimentos , Oceanos e Mares , Conservação dos Recursos Naturais , Alimentos Marinhos
12.
J Vasc Surg ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608965

RESUMO

OBJECTIVES: Society for Vascular Surgery guidelines recommend revascularization for patients with intermittent claudication (IC) if it can improve patient function and quality of life. However, it is still unclear if IC patients achieve a significant functional benefit from surgery compared to medical management alone. This study examines the relationship between IC treatment modality (operative vs. non-operative optimal medical management) and patient reported outcomes for physical function (PROMIS-PF) and satisfaction in social roles and activities (PROMIS-SA). METHODS: We identified patients with IC who presented for index evaluation in a vascular surgery clinic at an academic medical center between 2016 and 2021. Patients were stratified based on whether they underwent a revascularization procedure during follow-up versus continued non-operative management with medication and recommended exercise therapy. We used linear mixed-effect models to assess the relationship between treatment modality and PROMIS-PF, PROMIS-SA, and ankle-brachial index (ABI) over time, clustering among repeat patient observations. Models were adjusted for age, sex, diabetes, Charlson Comorbidity Index, Clinical Frailty Score, tobacco use, and index ABI. RESULTS: 225 IC patients were identified, of which 40% (N=89) underwent revascularization procedures (42% bypass, 58% PVI) and 60% (N=136) continued non-operative management. Patients were followed up to 6.9 years with an average follow-up of 5.2 +/- 1.6 years. Patients who underwent revascularization were more likely to be clinically frail (P=0.03), have a lower index ABI (0.55 +/- 0.24 vs. 0.72 +/- 0.28, P <0.001), and lower baseline PROMIS-PF score (36.72 +/- 8.2 vs. 40.40 +/- 6.73, P=0.01). There were no differences in patient demographics or medications between treatment groups. Examining patient reported outcome trends over time; there were no significant differences in PROMIS-PF between groups, trends over time, or group differences over time after adjusting for covariates (P= 0.07, 0.13, and 0.08, respectively). However, all patients with IC significantly increased their PROMIS-SA over time (adjusted P= 0.019), with patients managed non-operatively more likely to have an improvement in PROMIS-SA over time than those who underwent revascularization (adjusted P= 0.045). CONCLUSIONS: Patient-reported outcomes associated with functional status and satisfaction in activities are similar for patients with IC for up to 7 years, irrespective of whether they undergo treatment with revascularization or continue non-operative management. These findings support conservative long-term management for IC.

13.
bioRxiv ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38586000

RESUMO

Time-correlated single photon counting (TCSPC) coupled with confocal microscopy is a versatile biophysical tool that enables real-time monitoring of biomolecular dynamics across many timescales. With TCSPC, Fluorescence correlation spectroscopy (FCS) and pulsed interleaved excitation-Förster resonance energy transfer (PIE-FRET) are collected simultaneously on diffusing molecules to extract diffusion characteristics and proximity information. This article is a guide to calibrating FCS and PIE-FRET measurements with several biological samples including liposomes, streptavidin-coated quantum dots, proteins, and nucleic acids for reliable determination of diffusion coefficients and FRET efficiency. The FRET efficiency results are also compared to surface-attached single molecules using fluorescence lifetime imaging microscopy (FLIM-FRET). Combining the methods is a powerful approach to revealing mechanistic details of biological processes and pathways.

14.
Resusc Plus ; 17: 100598, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38497047

RESUMO

Background: During pulseless electrical activity (PEA) the cardiac mechanical and electrical functions are dissociated, a phenomenon occurring in 25-42% of in-hospital cardiac arrest (IHCA) cases. Accurate evaluation of the likelihood of a PEA patient transitioning to return of spontaneous circulation (ROSC) may be vital for the successful resuscitation. The aim: We sought to develop a model to automatically discriminate between PEA rhythms with favorable and unfavorable evolution to ROSC. Methods: A dataset of 190 patients, 120 with ROSC, were acquired with defibrillators from different vendors in three hospitals. The ECG and the transthoracic impedance (TTI) signal were processed to compute 16 waveform features. Logistic regression models where designed integrating both automated features and characteristics annotated in the QRS to identify PEAs with better prognosis leading to ROSC. Cross validation techniques were applied, both patient-specific and stratified, to evaluate the performance of the algorithm. Results: The best model consisted in a three feature algorithm that exhibited median (interquartile range) Area Under the Curve/Balanced accuracy/Sensitivity/Specificity of 80.3(9.9)/75.6(8.0)/ 77.4(15.2)/72.3(16.4) %, respectively. Conclusions: Information hidden in the waveforms of the ECG and TTI signals, along with QRS complex features, can predict the progression of PEA. Automated methods as the one proposed in this study, could contribute to assist in the targeted treatment of PEA in IHCA.

15.
Resusc Plus ; 18: 100606, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38533482

RESUMO

Background: Shock-refractory ventricular fibrillation (VF) or ventricular tachycardia (VT) is a treatment challenge in out-of-hospital cardiac arrest (OHCA). This study aimed to develop and validate machine learning models that could be implemented by emergency medical services (EMS) to predict refractory VF/VT in OHCA patients. Methods: This was a retrospective study examining adult non-traumatic OHCA patients brought into the emergency department by Singapore EMS from the Pan-Asian Resuscitation Outcomes Study (PAROS) registry. Data from April 2010 to March 2020 were extracted for this study. Refractory VF/VT was defined as VF/VT persisting or recurring after at least one shock. Features were selected based on expert clinical opinion and availability to dispatch prior to arrival at scene. Multivariable logistic regression (MVR), LASSO and random forest (RF) models were investigated. Model performance was evaluated using receiver operator characteristic (ROC) area under curve (AUC) analysis and calibration plots. Results: 20,713 patients were included in this study, of which 860 (4.1%) fulfilled the criteria for refractory VF/VT. All models performed comparably and were moderately well-calibrated. ROC-AUC were 0.732 (95% CI, 0.695 - 0.769) for MVR, 0.738 (95% CI, 0.701 - 0.774) for LASSO, and 0.731 (95% CI, 0.690 - 0.773) for RF. The shared important predictors across all models included male gender and public location. Conclusion: The machine learning models developed have potential clinical utility to improve outcomes in cases of refractory VF/VT OHCA. Prediction of refractory VF/VT prior to arrival at patient's side may allow for increased options for intervention both by EMS and tertiary care centres.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38503628

RESUMO

OBJECTIVES: To determine the impact of pressure recovery (PR) adjustment on disease severity grading in patients with severe aortic stenosis. The authors hypothesized that accounting for PR would result in echocardiographic reclassification of aortic stenosis severity in a significant number of patients. DESIGN: A retrospective observational study between October 2013 and February 2021. SETTING: A single-center, quaternary-care academic center. PARTICIPANTS: Adults (≥18 years old) who underwent transcatheter aortic valve implantation (TAVI). INTERVENTIONS: TAVI. MEASUREMENTS AND MAIN RESULTS: A total of 342 patients were evaluated in this study. Left ventricle mass index was significantly greater in patients who continued to be severe after PR (100.47 ± 28.77 v 90.15 ± 24.03, p = < 0.000001). Using PR-adjusted aortic valve area (AVA) resulted in the reclassification of 81 patients (24%) from severe to moderate aortic stenosis (AVA >1.0 cm2). Of the 81 patients who were reclassified, 23 patients (28%) had sinotubular junction (STJ) diameters >3.0 cm. CONCLUSION: Adjusting calculated AVA for PR resulted in a reclassification of a significant number of adult patients from severe to moderate aortic stenosis. PR was significantly larger in patients who reclassified from severe to moderate aortic stenosis after adjusting for PR. PR appeared to remain relevant in patients with STJ ≥3.0 cm. Clinicians need to be aware of PR and how to account for its effect when measuring pressure gradients with Doppler.

18.
Cell Rep ; 43(4): 113839, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38507409

RESUMO

Homeostatic regulation of synapses is vital for nervous system function and key to understanding a range of neurological conditions. Synaptic homeostasis is proposed to operate over hours to counteract the destabilizing influence of long-term potentiation (LTP) and long-term depression (LTD). The prevailing view holds that synaptic scaling is a slow first-order process that regulates postsynaptic glutamate receptors and fundamentally differs from LTP or LTD. Surprisingly, we find that the dynamics of scaling induced by neuronal inactivity are not exponential or monotonic, and the mechanism requires calcineurin and CaMKII, molecules dominant in LTD and LTP. Our quantitative model of these enzymes reconstructs the unexpected dynamics of homeostatic scaling and reveals how synapses can efficiently safeguard future capacity for synaptic plasticity. This mechanism of synaptic adaptation supports a broader set of homeostatic changes, including action potential autoregulation, and invites further inquiry into how such a mechanism varies in health and disease.

19.
JAMA Surg ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477914

RESUMO

Importance: National data on the development of competence during training have been reported using the Accreditation Council for Graduate Medical Education (ACGME) Milestones system. It is now possible to consider longitudinal analyses that link Milestone ratings during training to patient outcomes data of recent graduates. Objective: To evaluate the association of in-training ACGME Milestone ratings in a surgical specialty with subsequent complication rates following a commonly performed operation, endovascular aortic aneurysm repair (EVAR). Design, Setting, and Participants: This study of patient outcomes followed EVAR in the Vascular Quality Initiative (VQI) registry (4213 admissions from 208 hospitals treated by 327 surgeons). All surgeons included in this study graduated from ACGME-accredited training programs from 2015 through 2019 and had Milestone ratings 6 months prior to graduation. Data were analyzed from December 1, 2021, through September 15, 2023. Because Milestone ratings can vary with program, they were corrected for program effect using a deviation score from the program mean. Exposure: Milestone ratings assigned to individual trainees 6 months prior to graduation, based on judgments of surgical competence. Main Outcomes and Measures: Surgical complications following EVAR for patients treated by recent graduates during the index hospitalization, obtained using the nationwide Society for Vascular Surgery Patient Safety Organization's VQI registry, which includes 929 participating centers in 49 US states. Results: The study included outcomes for 4213 patients (mean [SD] age, 73.25 [8.74] years; 3379 male participants [80.2%]). Postoperative complications included 9.5% major (400 of 4213 cases) and 30.2% minor (1274 of 4213 cases) complications. After adjusting for patient risk factors and site of training, a significant association was identified between individual Milestone ratings of surgical trainees and major complications in early surgical practice in programs with lower mean Milestone ratings (odds ratio, 0.50; 95% CI; 0.27-0.95). Conclusions and Relevance: In this study, Milestone assessments of surgical trainees were associated with subsequent clinical outcomes in their early career. Although these findings represent one surgical specialty, they suggest Milestone ratings can be used in any specialty to identify trainees at risk for future adverse patient outcomes when applying the same theory and methodology. Milestones data should inform data-driven educational interventions and trainee remediation to optimize future patient outcomes.

20.
J Pediatr ; : 113923, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38492913

RESUMO

OBJECTIVE: To describe parents' motivations for and against participation in neonatal research, including the views of those who declined participation. STUDY DESIGN: We performed 44 semi-structured, qualitative interviews of parents approached for neonatal research. Here we describe their motivations for and against participation. RESULTS: Altruism was an important reason parents chose to participate. Some hoped participation in research would benefit their infant. Burdens of participation to the family, such as transportation to follow up (distinct from risks/burdens to the infant), were often deciding factors among those who declined participation. Perceived risks to the infant were reasons against participation, but parents often did not differentiate between baseline risks and incremental risk of study participation. Concerns regarding their infant being treated like a "guinea pig" were common among those who declined. Finally, historical abuses and institutional racism were reported as important concerns by some research decliners from minoritized populations. CONCLUSIONS: Within a diverse sample of parents approached to enroll their infant in neonatal research, motivations for and against participation emerged, which may be targets of future interventions. These motivations included reasons for participation which we may hope to encourage, such as altruism. They also included reasons against participation, which we may hope to, as feasible, eliminate, mitigate, or at least acknowledge. These findings can help clinical trialists, regulators, and funders attempting to improve neonatal research recruitment processes.

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