RESUMO
Elucidating the cellular architecture of the human cerebral cortex is central to understanding our cognitive abilities and susceptibility to disease. Here we used single-nucleus RNA-sequencing analysis to perform a comprehensive study of cell types in the middle temporal gyrus of human cortex. We identified a highly diverse set of excitatory and inhibitory neuron types that are mostly sparse, with excitatory types being less layer-restricted than expected. Comparison to similar mouse cortex single-cell RNA-sequencing datasets revealed a surprisingly well-conserved cellular architecture that enables matching of homologous types and predictions of properties of human cell types. Despite this general conservation, we also found extensive differences between homologous human and mouse cell types, including marked alterations in proportions, laminar distributions, gene expression and morphology. These species-specific features emphasize the importance of directly studying human brain.
Assuntos
Astrócitos/classificação , Evolução Biológica , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Neurônios/classificação , Adolescente , Adulto , Idoso , Animais , Astrócitos/citologia , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Inibição Neural , Neurônios/citologia , Análise de Componente Principal , RNA-Seq , Análise de Célula Única , Especificidade da Espécie , Transcriptoma/genética , Adulto JovemRESUMO
Single-cell genomics is rapidly advancing our knowledge of the diversity of cell phenotypes, including both cell types and cell states. Driven by single-cell/-nucleus RNA sequencing (scRNA-seq), comprehensive cell atlas projects characterizing a wide range of organisms and tissues are currently underway. As a result, it is critical that the transcriptional phenotypes discovered are defined and disseminated in a consistent and concise manner. Molecular biomarkers have historically played an important role in biological research, from defining immune cell types by surface protein expression to defining diseases by their molecular drivers. Here, we describe a machine learning-based marker gene selection algorithm, NS-Forest version 2.0, which leverages the nonlinear attributes of random forest feature selection and a binary expression scoring approach to discover the minimal marker gene expression combinations that optimally capture the cell type identity represented in complete scRNA-seq transcriptional profiles. The marker genes selected provide an expression barcode that serves as both a useful tool for downstream biological investigation and the necessary and sufficient characteristics for semantic cell type definition. The use of NS-Forest to identify marker genes for human brain middle temporal gyrus cell types reveals the importance of cell signaling and noncoding RNAs in neuronal cell type identity.
Assuntos
Perfilação da Expressão Gênica , Análise de Célula Única , Biomarcadores , Perfilação da Expressão Gênica/métodos , Aprendizado de Máquina , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodosRESUMO
Non-HLA antibodies against heterogeneous targets on endothelial cells have been associated with allograft injuries. The endothelial cell crossmatch (ECXM) is used in the detection of non-HLA antibodies but remains non-discriminatory for specific antibody identification. The primary objective of this study was to delineate the specific non-HLA antibody signatures associated with ECXM positivity and to determine the correlation of ECXM status and non-HLA antibody signatures on allograft health. Serum specimens from 25 lung transplant recipients (LTRs) and 13 renal transplant recipients (RTRs) were collected as part of clinical evaluation, and testing for angiotensin II receptor type 1 (AT1R) and donor-specific MHC class I chain-related gene A (MICA) antibodies and ECXM was performed. Remnant sera were tested for non-HLA antibodies using the LABScreen™ Autoantibody (LSAUT) Group 1, 2, and 3 kits (One Lambda, Inc., Los Angeles, CA, USA). In both cohorts, the concordance of AT1R and MICA together or individually with ECXM+ status was poor (<0.7), suggesting the presence of other unaccounted antibodies. Autoantibody profiling revealed three distinct clusters targeting fibrotic products, cytoskeletal proteins, and cell signaling molecules. A comparative analysis of ECXM+ and ECXM- specimens identified nine and five differentially expressed antibodies in the LTR and RTR cohorts, respectively. Employing machine learning techniques (variable importance, feature selection, ROC-AUC), we derived a five-antibody panel (TNFα, collagen V, CXCL11, GDNF, GAPDH) and a two-antibody panel (TNFα, CXCL9) that effectively discriminated between ECXM+ and ECXM- status in the LTR and RTR cohorts, respectively. Distinct antibody signatures were identified in LTR and RTR cohorts that correlated with ECXM+ status and were associated with allograft dysfunction.
Assuntos
Autoanticorpos , Antígenos de Histocompatibilidade Classe I , Transplante de Rim , Transplante de Pulmão , Humanos , Transplante de Rim/efeitos adversos , Transplante de Pulmão/efeitos adversos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Antígenos de Histocompatibilidade Classe I/imunologia , Autoanticorpos/imunologia , Autoanticorpos/sangue , Receptor Tipo 1 de Angiotensina/imunologia , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Teste de Histocompatibilidade/métodos , Transplantados , Antígenos HLA/imunologia , Idoso , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/sangueRESUMO
OBJECTIVE: Waitlist time for United Network for Organ Sharing Status 2 heart transplant candidates has steadily increased. We compared a bridging strategy using either the Impella 5.0/5.5 ("Impella") or intra-aortic balloon pump with a durable left ventricular assist device in patients with blood type O stratified by body habitus. METHODS: The United Network for Organ Sharing registry was queried for adults listed for de novo heart transplantation (without dialysis) supported by the Impella, an intra-aortic balloon pump, or the HeartMate 3 left ventricular assist device. The primary outcome was 1-year postlisting survival, defined as the sum of waitlist time and post-heart transplant survival time if the candidate underwent heart transplantation. RESULTS: In total, 2942 candidates were included (Impella: 214; intra-aortic balloon pump: 1326; HeartMate 3: 1402). Listing with the Impella or intra-aortic balloon pump was associated with worse postlisting survival compared with the HeartMate 3 left ventricular assist device in type O candidates (Impella: hazard ratio, 2.90 [95% CI, 1.48-5.67], P = .002; intra-aortic balloon pump: hazard ratio, 2.42 [95% CI, 1.59-3.68], P < .001) but less so in non-type O candidates. Further analysis of type O candidates demonstrated that the Impella and intra-aortic balloon pump were associated with a lower risk of postlisting mortality among those with normal height (25-75th percentile) and nonobese (body mass index <30) (Impella: hazard ratio, 1.78 [95% CI, 0.61-5.18], P = .292; intra-aortic balloon pump: hazard ratio, 1.28 [95% CI, 0.67-2.45], P = .455); among those not of normal height and nonobese, the Impella and intra-aortic balloon pump were associated with an elevated risk of postlisting mortality (Impella: hazard ratio, 3.65 [95% CI, 1.68-7.95], P = .001; intra-aortic balloon pump: hazard ratio, 3.01 [95% CI, 1.95-4.67], P < .001). CONCLUSIONS: Blood type O candidates listed with the Impella or intra-aortic balloon pump are at increased risk of postlisting mortality compared with a durable left ventricular assist device in the current organ allocation era. These effects are diminished among those with normal height and body habitus.
RESUMO
Veno-venous extracorporeal membrane oxygenation (VV ECMO) is used as a treatment modality in those who fail to respond to conventional care. Hypoxia and medications used in the intensive care unit may increase risk for atrial arrhythmias (AA). This study aims to evaluate the impact of AA on post-VV ECMO outcome. A retrospective review of patients who were placed on VV ECMO between October 2016 and October 2021. One hundred forty-five patients were divided into two groups, AA and no AA. Baseline characteristic and potential risk factors were assessed. Uni- and multivariate analysis using logistic regression models were constructed to evaluate the predictors of mortality between groups. Survival between groups was estimated by the Kaplan-Meier method using the log-rank test. Advanced age with history of coronary artery disease and hypertension were associated with increased risk to develop AA post-VV ECMO placement ( p value < 0.05). Length on ECMO, time intubated, hospital length of stay, and sepsis were significantly increased in patients in the AA group ( p value < 0.05). There was no difference in the overall mortality between the two groups. AAs were associated with worse hospital course and complications but no difference in overall mortality rate. Age and cardiovascular disease seem to be predisposing risk factors for this. Further studies are needed to investigate potential strategies to prevent AAs development in this population.
Assuntos
Fibrilação Atrial , Oxigenação por Membrana Extracorpórea , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Estudos Retrospectivos , Fatores de Risco , Análise MultivariadaRESUMO
BACKGROUND: Thromboembolic complications are common post-lung transplant, leading to significant morbidity. We instituted multiple interventions because of an observed 36.8% incidence of venous thromboembolism (VTE) (Incidence rate (IR) 5.74/1000 pt days) in our recipients. METHODS: Our initiative commenced January 2015 with enoxaparin initiation within 6-8 hours of intensive care unit arrival and continuation for 4-6 weeks. We evaluated the IR of VTE in lung transplant recipients within 90 days of transplant. In 2017, the protocol was modified to extend the time to initiation of prophylaxis to within 72 hours of ICU arrival. In 2019, we further amended our intraoperative vascular access strategy. RESULTS: Eighteen of 26 lung transplant recipients (LTR) met inclusion criteria in the 2015 cohort. Six of 18 (33.3%) developed VTE, 50% of which were upper extremity (UE), line associated. Fifty two of 75 LTR were eligible for enoxaparin prophylaxis in the 2017 cohort. Fifteen of 52 subjects (28.8%) developed VTE, 77.8% of which were UE and line associated. Despite improved adherence in 2017, there was little change in VTE IR (3.90/1000 pt days compared with 3.85/1000 pt days). Twenty six of 43 LTR met protocol inclusion criteria in the 2019 cohort. Ten subjects (38.5%) developed VTE, 67% of which were UE and line associated (IR 5.18/1000 pt days). CONCLUSION: Our prospective study found that LTR remain at high risk for VTE despite aggressive prophylaxis with 4-6 weeks of enoxaparin and adjustment of vascular access approach. Alternative interventions should be investigated to minimize VTE development in this vulnerable population.