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1.
N Engl J Med ; 389(26): 2446-2456, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-37952133

RESUMO

BACKGROUND: A strategy of administering a transfusion only when the hemoglobin level falls below 7 or 8 g per deciliter has been widely adopted. However, patients with acute myocardial infarction may benefit from a higher hemoglobin level. METHODS: In this phase 3, interventional trial, we randomly assigned patients with myocardial infarction and a hemoglobin level of less than 10 g per deciliter to a restrictive transfusion strategy (hemoglobin cutoff for transfusion, 7 or 8 g per deciliter) or a liberal transfusion strategy (hemoglobin cutoff, <10 g per deciliter). The primary outcome was a composite of myocardial infarction or death at 30 days. RESULTS: A total of 3504 patients were included in the primary analysis. The mean (±SD) number of red-cell units that were transfused was 0.7±1.6 in the restrictive-strategy group and 2.5±2.3 in the liberal-strategy group. The mean hemoglobin level was 1.3 to 1.6 g per deciliter lower in the restrictive-strategy group than in the liberal-strategy group on days 1 to 3 after randomization. A primary-outcome event occurred in 295 of 1749 patients (16.9%) in the restrictive-strategy group and in 255 of 1755 patients (14.5%) in the liberal-strategy group (risk ratio modeled with multiple imputation for incomplete follow-up, 1.15; 95% confidence interval [CI], 0.99 to 1.34; P = 0.07). Death occurred in 9.9% of the patients with the restrictive strategy and in 8.3% of the patients with the liberal strategy (risk ratio, 1.19; 95% CI, 0.96 to 1.47); myocardial infarction occurred in 8.5% and 7.2% of the patients, respectively (risk ratio, 1.19; 95% CI, 0.94 to 1.49). CONCLUSIONS: In patients with acute myocardial infarction and anemia, a liberal transfusion strategy did not significantly reduce the risk of recurrent myocardial infarction or death at 30 days. However, potential harms of a restrictive transfusion strategy cannot be excluded. (Funded by the National Heart, Lung, and Blood Institute and others; MINT ClinicalTrials.gov number, NCT02981407.).


Assuntos
Anemia , Transfusão de Sangue , Infarto do Miocárdio , Humanos , Anemia/sangue , Anemia/etiologia , Anemia/terapia , Transfusão de Sangue/métodos , Transfusão de Eritrócitos/efeitos adversos , Transfusão de Eritrócitos/métodos , Hemoglobinas/análise , Infarto do Miocárdio/sangue , Infarto do Miocárdio/complicações , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/terapia , Recidiva
2.
Proc Natl Acad Sci U S A ; 120(26): e2220343120, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37339196

RESUMO

In bacterial voltage-gated sodium channels, the passage of ions through the pore is controlled by a selectivity filter (SF) composed of four glutamate residues. The mechanism of selectivity has been the subject of intense research, with suggested mechanisms based on steric effects, and ion-triggered conformational change. Here, we propose an alternative mechanism based on ion-triggered shifts in pKa values of SF glutamates. We study the NavMs channel for which the open channel structure is available. Our free-energy calculations based on molecular dynamics simulations suggest that pKa values of the four glutamates are higher in solution of K+ ions than in solution of Na+ ions. Higher pKa in the presence of K+ stems primarily from the higher population of dunked conformations of the protonated Glu sidechain, which exhibit a higher pKa shift. Since pKa values are close to the physiological pH, this results in predominant population of the fully deprotonated state of glutamates in Na+ solution, while protonated states are predominantly populated in K+ solution. Through molecular dynamics simulations we calculate that the deprotonated state is the most conductive, the singly protonated state is less conductive, and the doubly protonated state has significantly reduced conductance. Thus, we propose that a significant component of selectivity is achieved through ion-triggered shifts in the protonation state, which favors more conductive states for Na+ ions and less conductive states for K+ ions. This mechanism also suggests a strong pH dependence of selectivity, which has been experimentally observed in structurally similar NaChBac channels.


Assuntos
Bactérias , Canais de Sódio Disparados por Voltagem , Íons , Bactérias/metabolismo , Simulação de Dinâmica Molecular , Glutamatos , Potássio/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(40): e2305292120, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37751551

RESUMO

Failure of contextual retrieval can lead to false recall, wherein people retrieve an item or experience that occurred in a different context or did not occur at all. Whereas the hippocampus is thought to play a crucial role in memory retrieval, we lack understanding of how the hippocampus supports retrieval of items related to a target context while disregarding related but irrelevant information. Using direct electrical recordings from the human hippocampus, we investigate the neural process underlying contextual misattribution of false memories. In two large datasets, we characterize key physiological differences between correct and false recalls that emerge immediately prior to vocalization. By differentiating between false recalls that share high or low contextual similarity with the target context, we show that low-frequency activity (6 to 18 Hz) in the hippocampus tracks similarity between the current and retrieved context. Applying multivariate decoding methods, we were able to reliably predict the contextual source of the to-be-recalled item. Our findings elucidate one of the hallmark features of episodic memory: our ability to distinguish between memories that were formed on different occasions.


Assuntos
Memória Episódica , Rememoração Mental , Humanos , Eletricidade , Hipocampo
4.
Biophys J ; 123(12): 1648-1653, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38733082

RESUMO

DNA primase is an iron sulfur enzyme in DNA replication responsible for synthesizing short RNA primers that serve as starting points for DNA synthesis. The role of the [4Fe-4S] cluster is not well determined. Here, we calculate the redox potential of the [4Fe-4S] with and without DNA/RNA using continuum electrostatics. In addition, we identify the structural changes coupled to the oxidation/reduction. Our calculations show that the DNA/RNA primer lowers the redox potential by 110 and 50 mV for the [4Fe-4S]+ and [4Fe-4S]2+ states, respectively. The oxidation of the cluster is coupled to structural changes that significantly reduce the binding energies between the DNA and the nearby residues. The negative charges accumulated by the DNA and the RNA primers induce the oxidation of the [4Fe-4S] cluster. This in turn stimulates structural changes on the DNA-protein interface that significantly reduce the binding energies.


Assuntos
DNA Primase , Proteínas Ferro-Enxofre , Oxirredução , Ligação Proteica , RNA , DNA Primase/metabolismo , DNA Primase/química , RNA/metabolismo , RNA/química , Proteínas Ferro-Enxofre/química , Proteínas Ferro-Enxofre/metabolismo , DNA/metabolismo , DNA/química , Termodinâmica , Modelos Moleculares
5.
J Comput Chem ; 45(10): 633-637, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38071482

RESUMO

The grid inhomogeneous solvation theory (GIST) method requires the often time-consuming calculation of water-water and water-solute energy on a grid. Previous efforts to speed up this calculation include using OpenMP, GPUs, and particle mesh Ewald. This article details how the speed of this calculation can be increased by parallelizing it with MPI, where trajectory frames are divided among multiple processors. This requires very little communication between individual processes during trajectory processing, meaning the calculation scales well to large processor counts. This article also details how the entropy calculation, which must happen after trajectory processing since it requires information from all trajectory frames, is parallelized via MPI. This parallelized GIST method has been implemented in the freely-available CPPTRAJ analysis software.

6.
Rheumatology (Oxford) ; 63(3): 594-607, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37725352

RESUMO

Biologic and targeted synthetic DMARDs (b/tsDMARDs) have revolutionized the management of multiple rheumatic inflammatory conditions. Among these, polyarticular JIA (pJIA) and RA display similarities in terms of disease pathophysiology and response pattern to b/tsDMARDs. Indeed, the therapeutic efficacy of novel targeted drugs is variable among individual patients, in both RA and pJIA. The mechanisms and determinants of this heterogeneous response are diverse and complex, such that the development of true 'precision'-medicine strategies has proven highly challenging. In this review, we will discuss pathophysiological, patient-specific, drug-specific and environmental factors contributing to individual therapeutic response in pJIA in comparison with what is known in RA. Although some biomarkers have been identified that stratify with respect to the likelihood of either therapeutic response or non-response, few have proved useful in clinical practice so far, likely due to the complexity of treatment-response mechanisms. Consequently, we propose a pragmatic, patient-centred and clinically based approach, i.e. personalized instead of biomarker-based precision medicine in JIA.


Assuntos
Antirreumáticos , Artrite , Adulto , Humanos , Medicina de Precisão , Inflamação , Antirreumáticos/uso terapêutico
7.
J Acoust Soc Am ; 155(3): 2181-2191, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38512016

RESUMO

Data captured by a Synthetic Aperture Sonar (SAS) near Mobile Bay during the 2021 Undersea Remote Sensing experiment funded by the Office of Naval Research reveals near surface bubble clouds from wave breaking events and a large aggregation of fish. Tools developed for using SAS data to image hydrodynamic features in the water column were applied to observations of the bubble clouds and fish aggregation. Combining imagery and height data captured by the sonar array with a detection and tracking algorithm enables the trajectories, velocities, and behavior of fish in the aggregation to be observed. Fitting the velocity and height data of the tracked objects to a Gaussian mixture model and performing cluster analysis enables an estimate of the near-surface ambient velocity via observation of the movement of the bubble traces and the general direction of motion of the fish aggregation. We find that the velocity traces associated with bubbles are consistent with ambient currents as opposed to the direction of propagating wave crests while velocities of fish indicate relatively large, pelagic species.


Assuntos
Algoritmos , Movimento , Animais , Movimento (Física) , Peixes , Hidrodinâmica
8.
N Engl J Med ; 382(17): 1619-1628, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32227754

RESUMO

BACKGROUND: In the ISCHEMIA-CKD trial, the primary analysis showed no significant difference in the risk of death or myocardial infarction with initial angiography and revascularization plus guideline-based medical therapy (invasive strategy) as compared with guideline-based medical therapy alone (conservative strategy) in participants with stable ischemic heart disease, moderate or severe ischemia, and advanced chronic kidney disease (an estimated glomerular filtration rate of <30 ml per minute per 1.73 m2 or receipt of dialysis). A secondary objective of the trial was to assess angina-related health status. METHODS: We assessed health status with the Seattle Angina Questionnaire (SAQ) before randomization and at 1.5, 3, and 6 months and every 6 months thereafter. The primary outcome of this analysis was the SAQ Summary score (ranging from 0 to 100, with higher scores indicating less frequent angina and better function and quality of life). Mixed-effects cumulative probability models within a Bayesian framework were used to estimate the treatment effect with the invasive strategy. RESULTS: Health status was assessed in 705 of 777 participants. Nearly half the participants (49%) had had no angina during the month before randomization. At 3 months, the estimated mean difference between the invasive-strategy group and the conservative-strategy group in the SAQ Summary score was 2.1 points (95% credible interval, -0.4 to 4.6), a result that favored the invasive strategy. The mean difference in score at 3 months was largest among participants with daily or weekly angina at baseline (10.1 points; 95% credible interval, 0.0 to 19.9), smaller among those with monthly angina at baseline (2.2 points; 95% credible interval, -2.0 to 6.2), and nearly absent among those without angina at baseline (0.6 points; 95% credible interval, -1.9 to 3.3). By 6 months, the between-group difference in the overall trial population was attenuated (0.5 points; 95% credible interval, -2.2 to 3.4). CONCLUSIONS: Participants with stable ischemic heart disease, moderate or severe ischemia, and advanced chronic kidney disease did not have substantial or sustained benefits with regard to angina-related health status with an initially invasive strategy as compared with a conservative strategy. (Funded by the National Heart, Lung, and Blood Institute; ISCHEMIA-CKD ClinicalTrials.gov number, NCT01985360.).


Assuntos
Angiografia Coronária , Ponte de Artéria Coronária , Nível de Saúde , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/cirurgia , Intervenção Coronária Percutânea , Insuficiência Renal Crônica/complicações , Idoso , Teste de Esforço , Feminino , Seguimentos , Estilo de Vida Saudável , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Isquemia Miocárdica/mortalidade , Razão de Chances , Modelos de Riscos Proporcionais , Inquéritos e Questionários
9.
N Engl J Med ; 382(17): 1608-1618, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32227756

RESUMO

BACKGROUND: Clinical trials that have assessed the effect of revascularization in patients with stable coronary disease have routinely excluded those with advanced chronic kidney disease. METHODS: We randomly assigned 777 patients with advanced kidney disease and moderate or severe ischemia on stress testing to be treated with an initial invasive strategy consisting of coronary angiography and revascularization (if appropriate) added to medical therapy or an initial conservative strategy consisting of medical therapy alone and angiography reserved for those in whom medical therapy had failed. The primary outcome was a composite of death or nonfatal myocardial infarction. A key secondary outcome was a composite of death, nonfatal myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. RESULTS: At a median follow-up of 2.2 years, a primary outcome event had occurred in 123 patients in the invasive-strategy group and in 129 patients in the conservative-strategy group (estimated 3-year event rate, 36.4% vs. 36.7%; adjusted hazard ratio, 1.01; 95% confidence interval [CI], 0.79 to 1.29; P = 0.95). Results for the key secondary outcome were similar (38.5% vs. 39.7%; hazard ratio, 1.01; 95% CI, 0.79 to 1.29). The invasive strategy was associated with a higher incidence of stroke than the conservative strategy (hazard ratio, 3.76; 95% CI, 1.52 to 9.32; P = 0.004) and with a higher incidence of death or initiation of dialysis (hazard ratio, 1.48; 95% CI, 1.04 to 2.11; P = 0.03). CONCLUSIONS: Among patients with stable coronary disease, advanced chronic kidney disease, and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of death or nonfatal myocardial infarction. (Funded by the National Heart, Lung, and Blood Institute and others; ISCHEMIA-CKD ClinicalTrials.gov number, NCT01985360.).


Assuntos
Angiografia Coronária , Ponte de Artéria Coronária , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/cirurgia , Intervenção Coronária Percutânea , Insuficiência Renal Crônica/complicações , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Bloqueadores dos Canais de Cálcio/uso terapêutico , Teste de Esforço , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/prevenção & controle , Isquemia Miocárdica/complicações , Isquemia Miocárdica/mortalidade , Fatores de Risco
10.
N Engl J Med ; 382(15): 1395-1407, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32227755

RESUMO

BACKGROUND: Among patients with stable coronary disease and moderate or severe ischemia, whether clinical outcomes are better in those who receive an invasive intervention plus medical therapy than in those who receive medical therapy alone is uncertain. METHODS: We randomly assigned 5179 patients with moderate or severe ischemia to an initial invasive strategy (angiography and revascularization when feasible) and medical therapy or to an initial conservative strategy of medical therapy alone and angiography if medical therapy failed. The primary outcome was a composite of death from cardiovascular causes, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. A key secondary outcome was death from cardiovascular causes or myocardial infarction. RESULTS: Over a median of 3.2 years, 318 primary outcome events occurred in the invasive-strategy group and 352 occurred in the conservative-strategy group. At 6 months, the cumulative event rate was 5.3% in the invasive-strategy group and 3.4% in the conservative-strategy group (difference, 1.9 percentage points; 95% confidence interval [CI], 0.8 to 3.0); at 5 years, the cumulative event rate was 16.4% and 18.2%, respectively (difference, -1.8 percentage points; 95% CI, -4.7 to 1.0). Results were similar with respect to the key secondary outcome. The incidence of the primary outcome was sensitive to the definition of myocardial infarction; a secondary analysis yielded more procedural myocardial infarctions of uncertain clinical importance. There were 145 deaths in the invasive-strategy group and 144 deaths in the conservative-strategy group (hazard ratio, 1.05; 95% CI, 0.83 to 1.32). CONCLUSIONS: Among patients with stable coronary disease and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of ischemic cardiovascular events or death from any cause over a median of 3.2 years. The trial findings were sensitive to the definition of myocardial infarction that was used. (Funded by the National Heart, Lung, and Blood Institute and others; ISCHEMIA ClinicalTrials.gov number, NCT01471522.).


Assuntos
Cateterismo Cardíaco , Ponte de Artéria Coronária , Doença das Coronárias/tratamento farmacológico , Doença das Coronárias/cirurgia , Revascularização Miocárdica/métodos , Intervenção Coronária Percutânea , Idoso , Angina Instável/epidemiologia , Teorema de Bayes , Doenças Cardiovasculares/mortalidade , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/terapia , Qualidade de Vida
11.
Am Heart J ; 257: 120-129, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36417955

RESUMO

BACKGROUND: Accumulating evidence from clinical trials suggests that a lower (restrictive) hemoglobin threshold (<8 g/dL) for red blood cell (RBC) transfusion, compared with a higher (liberal) threshold (≥10 g/dL) is safe. However, in anemic patients with acute myocardial infarction (MI), maintaining a higher hemoglobin level may increase oxygen delivery to vulnerable myocardium resulting in improved clinical outcomes. Conversely, RBC transfusion may result in increased blood viscosity, vascular inflammation, and reduction in available nitric oxide resulting in worse clinical outcomes. We hypothesize that a liberal transfusion strategy would improve clinical outcomes as compared to a more restrictive strategy. METHODS: We will enroll 3500 patients with acute MI (type 1, 2, 4b or 4c) as defined by the Third Universal Definition of MI and a hemoglobin <10 g/dL at 144 centers in the United States, Canada, France, Brazil, New Zealand, and Australia. We randomly assign trial participants to a liberal or restrictive transfusion strategy. Participants assigned to the liberal strategy receive transfusion of RBCs sufficient to raise their hemoglobin to at least 10 g/dL. Participants assigned to the restrictive strategy are permitted to receive transfusion of RBCs if the hemoglobin falls below 8 g/dL or for persistent angina despite medical therapy. We will contact each participant at 30 days to assess clinical outcomes and at 180 days to ascertain vital status. The primary end point is a composite of all-cause death or recurrent MI through 30 days following randomization. Secondary end points include all-cause mortality at 30 days, recurrent adjudicated MI, and the composite outcome of all-cause mortality, nonfatal recurrent MI, ischemia driven unscheduled coronary revascularization (percutaneous coronary intervention or coronary artery bypass grafting), or readmission to the hospital for ischemic cardiac diagnosis within 30 days. The trial will assess multiple tertiary end points. CONCLUSIONS: The MINT trial will inform RBC transfusion practice in patients with acute MI.


Assuntos
Anemia , Doença da Artéria Coronariana , Infarto do Miocárdio , Isquemia Miocárdica , Humanos , Anemia/etiologia , Anemia/terapia , Transfusão de Sangue , Doença da Artéria Coronariana/complicações , Hemoglobinas/metabolismo , Isquemia/etiologia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/terapia , Isquemia Miocárdica/complicações , Isquemia Miocárdica/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Ann Rheum Dis ; 82(12): 1538-1546, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37507201

RESUMO

OBJECTIVES: Transcriptomic profiling of synovial tissue from patients with early, untreated rheumatoid arthritis (RA) was used to explore the ability of unbiased, data-driven approaches to define clinically relevant subgroups. METHODS: RNASeq was performed on 74 samples, with disease activity data collected at inclusion. Principal components analysis (PCA) and unsupervised clustering were used to define patient clusters based on expression of the most variable genes, followed by pathway analysis and inference of relative abundance of immune cell subsets. Histological assessment and multiplex immunofluorescence (for CD45, CD68, CD206) were performed on paraffin sections. RESULTS: PCA on expression of the (n=894) most variable genes across this series did not divide samples into distinct groups, instead yielding a continuum correlated with baseline disease activity. Two patient clusters (PtC1, n=52; PtC2, n=22) were defined based on expression of these genes. PtC1, with significantly higher disease activity and probability of response to methotrexate therapy, showed upregulation of immune system genes; PtC2 showed upregulation of lipid metabolism genes, described to characterise tissue resident or M2-like macrophages. In keeping with these data, M2-like:M1-like macrophage ratios were inversely correlated with disease activity scores and were associated with lower synovial immune infiltration and the presence of thinner, M2-like macrophage-rich synovial lining layers. CONCLUSION: In this large series of early, untreated RA, we show that the synovial transcriptome closely mirrors clinical disease activity and correlates with synovial inflammation. Intriguingly, lower inflammation and disease activity are associated with higher ratios of M2:M1 macrophages, particularly striking in the synovial lining layer. This may point to a protective role for tissue resident macrophages in RA.


Assuntos
Artrite Reumatoide , Sinovite , Humanos , Transcriptoma , Sinovite/patologia , Membrana Sinovial/metabolismo , Inflamação
13.
Mol Phylogenet Evol ; 188: 107890, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37517508

RESUMO

African-Malagasy species of the bat genus Miniopterus are notable both for the dramatic increase in the number of newly recognized species over the last 15 years, as well as for the profusion of new taxa from Madagascar and the neighboring Comoros. Since 2007, seven new Malagasy Miniopterus species have been described compared to only two new species since 1936 from the Afrotropics. The conservative morphology of Miniopterus and limited geographic sampling in continental Africa have undoubtedly contributed to the deficit of continental species. In addition to uncertainty over species limits, phylogenetic relationships of Miniopterus remain mostly unresolved, particularly at deeper backbone nodes. Previous phylogenetic studies were based on limited taxon sampling and/or limited genetic sampling involving no more than five loci. Here, we conduct the first phylogenomic study of the Afrotropical Miniopteridae by analyzing up to 3772 genome-wide ultraconserved elements (UCEs) from historic and modern samples of 70 individuals from 25 Miniopterus species/lineages. We analyze multiple datasets of varying degrees of completeness (70, 90, and 100 percent complete) using partitioned concatenated maximum likelihood and multispecies coalescent methods. Our well-supported, species-level phylogenies resolved most (6/8 or 7/8) backbone nodes and strongly support for the first time the monophyly of the Malagasy radiation. We inferred the crown age of African Miniopteridae in the late Miocene (10.4 Ma), while the main lineages of Miniopterus appear to have contemporaneously diversified in two sister radiations in the Afrotropics and Madagascar. Species-level divergence of 23 of 25 African + Malagasy Miniopterus were estimated to have 95 % HPDs that overlap with the late Miocene (5.3-10.4 Ma). We present ancestral range estimates that unambiguously support a continental African radiation that originated in the Zambezian and Somalian/Ethiopian biogeographic regions, but we cannot rule out back colonization of Africa from Madagascar. The phylogeny indicates genetic support for up to seven new species.


Assuntos
Quirópteros , Humanos , Animais , Filogenia , Quirópteros/genética , África , Madagáscar
14.
Neurosurg Rev ; 46(1): 260, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37779135

RESUMO

Extracranial vertebral artery aneurysms are rare complications resulting from trauma and multiple different diseases. However, the difference between clinical and surgical profiles is well understood. To investigate the clinical and interventional outcomes following extracranial vertebral artery aneurysms (VAA) treatment through a systematic review of the literature to date, an electronic database search for full-text English articles was conducted following PRISMA guidelines. The search yielded results on clinical and surgical outcomes for extracranial VAAs. These results included patient-specific risk factors, indications, and techniques. Our literature search resulted in 561 articles, of which 36 studies were qualified to be included in the analysis. A total of 55 patients with multiple various extracranial VAA incidents were included. The mean age of subjects was 42 years (ranging from 13.0 to 76.0 years), and the majority of patients were males (71%, n =39). Blunt trauma was the most frequent risk factor for extracranial VAA formation (35%, n = 19). The majority of aneurysms (60%) were dissected in nature. The most common form of treatment for extracranial VAAs was the use of a flow diverter (24%, n=13). Overall, five (9%) patients had long-term adverse neurological complications following intervention with 5% (n=3) mortality, 2% (n=1) resulting in unilateral vocal cord paralysis, and 2% (n=1) resulted in a positive Romberg sign. The mortality rate is 15.7% in the surgical group, whereas the endovascular treatment did not result in any mortality. The endovascular approach is a safe and effective treatment of extracranial VAAs due to its relatively low overall complication rate and lack of resulting mortality. This is in contrast to the surgical approach which results in a higher rate of complications, recurrence, and mortality outcomes. An understanding of the factors and clinical outcomes associated with the incidence of extracranial VAAs is essential for the future improvement of patient outcomes.


Assuntos
Aneurisma , Procedimentos Endovasculares , Masculino , Humanos , Adulto , Feminino , Artéria Vertebral/cirurgia , Procedimentos Endovasculares/efeitos adversos , Estudos Retrospectivos , Aneurisma/cirurgia , Aneurisma/diagnóstico , Resultado do Tratamento
15.
Neurosurg Rev ; 46(1): 284, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37882896

RESUMO

Flow diversion with the pipeline embolization device (PED) is increasingly used to treat intracranial aneurysms with high obliteration rates and low morbidity. However, long-term (≥ 1 year) angiographic and clinical outcomes still require further investigation. The aim of this study was to compare the occlusion and complication rates for small (< 10 mm) versus large (10-25 mm) aneurysms at long-term following treatment with PED. A systematic review and meta-analysis were performed in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. We conducted a comprehensive search of English language databases including Ovid MEDLINE and Epub Ahead of Print, In-Process, and Daily, Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus. Our studies included a minimum of 10 patients treated with PED for small vs. large aneurysms and with at least 12 months of follow-up. The primary safety endpoint was the rate of clinical complications measured by the occurrence of symptomatic stroke (confirmed clinically and radiographically), intracranial hemorrhage, or aneurysmal rupture. The primary efficacy endpoint was the complete aneurysm occlusion rate. Our analysis included 19 studies with 1277 patients and 1493 aneurysms. Of those, 1378 aneurysms met our inclusion criteria. The mean age was 53.9 years, and most aneurysms were small (89.75%; N = 1340) in women (79.1%; N = 1010). The long-term occlusion rate was 73% (95%, CI 65 to 80%) in small compared to 84% (95%, CI 76 to 90%) in large aneurysms (p < 0.01). The symptomatic thromboembolic complication rate was 5% (95%, CI 3 to 9%) in small compared to 7% (95%, CI 4 to 13%) in large aneurysms (p = 0.01). The rupture rate was 2% vs. 4% (p = 0.92), and the rate of intracranial hemorrhage was 2% vs. 4% (p = 0.96) for small vs. large aneurysms, respectively; however, these differences were not statistically significant. The long-term occlusion rate after PED treatment is higher in large vs. small aneurysms. Symptomatic thromboembolic rates with stroke are also higher in large vs. small aneurysms. The difference in the rates of aneurysm rupture and intracranial hemorrhage was insignificant. Although the PED seems a safe and effective treatment for small and large aneurysms, further studies are required to clarify how occlusion rate and morbidity are affected by aneurysm size.


Assuntos
Aneurisma Roto , Aneurisma Intracraniano , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Aneurisma Roto/cirurgia , Aneurisma Intracraniano/cirurgia , Hemorragias Intracranianas , Angiografia
16.
Neurosurg Focus ; 54(6): E15, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37552641

RESUMO

OBJECTIVE: Chordomas are rare tumors from notochordal remnants and account for 1%-4% of all primary bone malignancies, often arising from the clivus and sacrum. Despite margin-negative resection and postoperative radiotherapy, chordomas often recur. Further, immunohistochemical (IHC) markers have not been assessed as predictive of chordoma recurrence. The authors aimed to identify the IHC markers that are predictive of postoperative long-term (≥ 1 year) chordoma recurrence by using trained multiple tree-based machine learning (ML) algorithms. METHODS: The authors reviewed the records of patients who had undergone treatment for clival and spinal chordomas between January 2017 and June 2021 across the Mayo Clinic enterprise (Minnesota, Florida, and Arizona). Demographics, type of treatment, histopathology, and other relevant clinical factors were abstracted from each patient record. Decision tree and random forest classifiers were trained and tested to predict long-term recurrence based on unseen data using an 80/20 split. RESULTS: One hundred fifty-one patients diagnosed and treated for chordomas were identified: 58 chordomas of the clivus, 48 chordomas of the mobile spine, and 45 chordomas sacrococcygeal in origin. Patients diagnosed with cervical chordomas were the oldest among all groups (58 ± 14 years, p = 0.009). Most patients were male (n = 91, 60.3%) and White (n = 139, 92.1%). Most patients underwent resection with or without radiation therapy (n = 129, 85.4%). Subtotal resection followed by radiation therapy (n = 51, 33.8%) was the most common treatment modality, followed by gross-total resection then radiation therapy (n = 43, 28.5%). Multivariate analysis showed that S100 and pan-cytokeratin are more likely to predict the increase in the risk of postoperative recurrence (OR 3.67, 95% CI 1.09-12.42, p= 0.03; and OR 3.74, 95% CI 0.05-2.21, p = 0.02, respectively). In the decision tree analysis, a clinical follow-up > 1897 days was found in 37% of encounters and a 90% chance of being classified for recurrence (accuracy = 77%). Random forest analysis (n = 500 trees) showed that patient age, type of surgical treatment, location of tumor, S100, pan-cytokeratin, and EMA are the factors predicting long-term recurrence. CONCLUSIONS: The IHC and clinicopathological variables combined with tree-based ML tools successfully demonstrated a high capacity to identify recurrence patterns with an accuracy of 77%. S100, pan-cytokeratin, and EMA were the IHC drivers of recurrence. This shows the power of ML algorithms in analyzing and predicting outcomes of rare conditions of a small sample size.


Assuntos
Cordoma , Neoplasias da Coluna Vertebral , Humanos , Resultado do Tratamento , Cordoma/cirurgia , Radioterapia Adjuvante , Neoplasias da Coluna Vertebral/cirurgia , Fossa Craniana Posterior/cirurgia , Estudos Retrospectivos , Recidiva Local de Neoplasia/cirurgia , Recidiva Local de Neoplasia/patologia
17.
Eur Heart J ; 43(2): 148-149, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-34514494

RESUMO

AIMS: The International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) trial prespecified an analysis to determine whether accounting for recurrent cardiovascular events in addition to first events modified understanding of the treatment effects. METHODS AND RESULTS: Patients with stable coronary artery disease (CAD) and moderate or severe ischaemia on stress testing were randomized to either initial invasive (INV) or initial conservative (CON) management. The primary outcome was a composite of cardiovascular death, myocardial infarction (MI), and hospitalization for unstable angina, heart failure, or cardiac arrest. The Ghosh-Lin method was used to estimate mean cumulative incidence of total events with death as a competing risk. The 5179 ISCHEMIA patients experienced 670 index events (318 INV, 352 CON) and 203 recurrent events (102 INV, 101 CON). A single primary event was observed in 9.8% of INV and 10.8% of CON patients while ≥2 primary events were observed in 2.5% and 2.8%, respectively. Patients with recurrent events were older; had more frequent hypertension, diabetes, prior MI, or cerebrovascular disease; and had more multivessel CAD. The average number of primary endpoint events per 100 patients over 4 years was 18.2 in INV [95% confidence interval (CI) 15.8-20.9] and 19.7 in CON (95% CI 17.5-22.2), difference -1.5 (95% CI -5.0 to 2.0, P = 0.398). Comparable results were obtained when all-cause death was substituted for cardiovascular death and when stroke was added as an event. CONCLUSIONS: In stable CAD patients with moderate or severe myocardial ischaemia enrolled in ISCHEMIA, an initial INV treatment strategy did not prevent either net recurrent events or net total events more effectively than an initial CON strategy. CLINICAL TRIAL REGISTRATION: ISCHEMIA ClinicalTrials.gov number, NCT01471522, https://clinicaltrials.gov/ct2/show/NCT01471522.


Assuntos
Doença da Artéria Coronariana , Isquemia Miocárdica , Angina Instável , Tratamento Conservador/métodos , Doença da Artéria Coronariana/terapia , Humanos , Isquemia , Isquemia Miocárdica/terapia
18.
Circulation ; 144(13): 1024-1038, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34496632

RESUMO

BACKGROUND: The ISCHEMIA trial (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) postulated that patients with stable coronary artery disease (CAD) and moderate or severe ischemia would benefit from revascularization. We investigated the relationship between severity of CAD and ischemia and trial outcomes, overall and by management strategy. METHODS: In total, 5179 patients with moderate or severe ischemia were randomized to an initial invasive or conservative management strategy. Blinded, core laboratory-interpreted coronary computed tomographic angiography was used to assess anatomic eligibility for randomization. Extent and severity of CAD were classified with the modified Duke Prognostic Index (n=2475, 48%). Ischemia severity was interpreted by independent core laboratories (nuclear, echocardiography, magnetic resonance imaging, exercise tolerance testing, n=5105, 99%). We compared 4-year event rates across subgroups defined by severity of ischemia and CAD. The primary end point for this analysis was all-cause mortality. Secondary end points were myocardial infarction (MI), cardiovascular death or MI, and the trial primary end point (cardiovascular death, MI, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest). RESULTS: Relative to mild/no ischemia, neither moderate ischemia nor severe ischemia was associated with increased mortality (moderate ischemia hazard ratio [HR], 0.89 [95% CI, 0.61-1.30]; severe ischemia HR, 0.83 [95% CI, 0.57-1.21]; P=0.33). Nonfatal MI rates increased with worsening ischemia severity (HR for moderate ischemia, 1.20 [95% CI, 0.86-1.69] versus mild/no ischemia; HR for severe ischemia, 1.37 [95% CI, 0.98-1.91]; P=0.04 for trend, P=NS after adjustment for CAD). Increasing CAD severity was associated with death (HR, 2.72 [95% CI, 1.06-6.98]) and MI (HR, 3.78 [95% CI, 1.63-8.78]) for the most versus least severe CAD subgroup. Ischemia severity did not identify a subgroup with treatment benefit on mortality, MI, the trial primary end point, or cardiovascular death or MI. In the most severe CAD subgroup (n=659), the 4-year rate of cardiovascular death or MI was lower in the invasive strategy group (difference, 6.3% [95% CI, 0.2%-12.4%]), but 4-year all-cause mortality was similar. CONCLUSIONS: Ischemia severity was not associated with increased risk after adjustment for CAD severity. More severe CAD was associated with increased risk. Invasive management did not lower all-cause mortality at 4 years in any ischemia or CAD subgroup. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01471522.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/patologia , Feminino , Humanos , Isquemia , Masculino , Resultado do Tratamento
19.
Circulation ; 143(8): 790-804, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33267610

RESUMO

BACKGROUND: In the ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches), an initial invasive strategy did not significantly reduce rates of cardiovascular events or all-cause mortality in comparison with a conservative strategy in patients with stable ischemic heart disease and moderate/severe myocardial ischemia. The most frequent component of composite cardiovascular end points was myocardial infarction (MI). METHODS: ISCHEMIA prespecified that the primary and major secondary composite end points of the trial be analyzed using 2 MI definitions. For procedural MI, the primary MI definition used creatine kinase-MB as the preferred biomarker, whereas the secondary definition used cardiac troponin. Procedural thresholds were >5 times the upper reference level for percutaneous coronary intervention and >10 times for coronary artery bypass grafting. Procedural MI definitions included (1) a category of elevated biomarker only events with much higher biomarker thresholds, (2) new ST-segment depression of ≥1 mm for the primary and ≥0.5 mm for the secondary definition, and (3) new coronary dissections >National Heart, Lung, and Blood Institute grade 3. We compared MI type, frequency, and prognosis by treatment assignment using both MI definitions. RESULTS: Procedural MIs accounted for 20.1% of all MI events with the primary definition and 40.6% of all MI events with the secondary definition. Four-year MI rates in patients undergoing revascularization were more frequent with the invasive versus conservative strategy using the primary (2.7% versus 1.1%; adjusted hazard ratio [HR], 2.98 [95% CI, 1.87-4.73]) and secondary (8.2% versus 2.0%; adjusted HR, 5.04 [95% CI, 3.64-6.97]) MI definitions. Type 1 MIs were less frequent with the invasive versus conservative strategy using the primary (3.40% versus 6.89%; adjusted HR, 0.53 [95% CI, 0.41-0.69]; P<0.0001) and secondary (3.48% versus 6.89%; adjusted HR, 0.53 [95% CI, 0.41-0.69]; P<0.0001) definitions. The risk of subsequent cardiovascular death was higher after a type 1 MI than after no MI using the primary (adjusted HR, 3.38 [95% CI, 2.03-5.61]; P<0.001) or secondary MI definition (adjusted HR, 3.52 [2.11-5.88]; P<0.001). CONCLUSIONS: In ISCHEMIA, type 1 MI events using the primary and secondary definitions during 5-year follow-up were more frequent with an initial conservative strategy and associated with subsequent cardiovascular death. Procedural MI rates were greater in the invasive strategy and with the use of the secondary MI definition. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01471522.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Infarto do Miocárdio/patologia , Intervenção Coronária Percutânea/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Creatina Quinase Forma MB/sangue , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/mortalidade , Isquemia Miocárdica/terapia , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco , Índice de Gravidade de Doença , Análise de Sobrevida
20.
Circulation ; 144(17): 1380-1395, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34521217

RESUMO

BACKGROUND: Among patients with diabetes and chronic coronary disease, it is unclear if invasive management improves outcomes when added to medical therapy. METHODS: The ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) trials (ie, ISCHEMIA and ISCHEMIA-Chronic Kidney Disease) randomized chronic coronary disease patients to an invasive (medical therapy + angiography and revascularization if feasible) or a conservative approach (medical therapy alone with revascularization if medical therapy failed). Cohorts were combined after no trial-specific effects were observed. Diabetes was defined by history, hemoglobin A1c ≥6.5%, or use of glucose-lowering medication. The primary outcome was all-cause death or myocardial infarction (MI). Heterogeneity of effect of invasive management on death or MI was evaluated using a Bayesian approach to protect against random high or low estimates of treatment effect for patients with versus without diabetes and for diabetes subgroups of clinical (female sex and insulin use) and anatomic features (coronary artery disease severity or left ventricular function). RESULTS: Of 5900 participants with complete baseline data, the median age was 64 years (interquartile range, 57-70), 24% were female, and the median estimated glomerular filtration was 80 mL·min-1·1.73-2 (interquartile range, 64-95). Among the 2553 (43%) of participants with diabetes, the median percent hemoglobin A1c was 7% (interquartile range, 7-8), and 30% were insulin-treated. Participants with diabetes had a 49% increased hazard of death or MI (hazard ratio, 1.49 [95% CI, 1.31-1.70]; P<0.001). At median 3.1-year follow-up the adjusted event-free survival was 0.54 (95% bootstrapped CI, 0.48-0.60) and 0.66 (95% bootstrapped CI, 0.61-0.71) for patients with diabetes versus without diabetes, respectively, with a 12% (95% bootstrapped CI, 4%-20%) absolute decrease in event-free survival among participants with diabetes. Female and male patients with insulin-treated diabetes had an adjusted event-free survival of 0.52 (95% bootstrapped CI, 0.42-0.56) and 0.49 (95% bootstrapped CI, 0.42-0.56), respectively. There was no difference in death or MI between strategies for patients with diabetes versus without diabetes, or for clinical (female sex or insulin use) or anatomic features (coronary artery disease severity or left ventricular function) of patients with diabetes. CONCLUSIONS: Despite higher risk for death or MI, chronic coronary disease patients with diabetes did not derive incremental benefit from routine invasive management compared with initial medical therapy alone. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01471522.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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