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1.
Med Microbiol Immunol ; 211(1): 37-48, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35034207

RESUMO

Mechanisms underlying the SARS-CoV-2-triggered hyperacute thrombo-inflammatory response that causes multi-organ damage in coronavirus disease 2019 (COVID-19) are poorly understood. Several lines of evidence implicate overactivation of complement. To delineate the involvement of complement in COVID-19, we prospectively studied 25 ICU-hospitalized patients for up to 21 days. Complement biomarkers in patient sera and healthy controls were quantified by enzyme-linked immunosorbent assays. Correlations with respiratory function and mortality were analyzed. Activation of complement via the classical/lectin pathways was variably increased. Strikingly, all patients had increased activation of the alternative pathway (AP) with elevated levels of activation fragments, Ba and Bb. This was associated with a reduction of the AP negative regulator, factor (F) H. Correspondingly, terminal pathway biomarkers of complement activation, C5a and sC5b-9, were significantly elevated in all COVID-19 patient sera. C5a and AP constituents Ba and Bb, were significantly associated with hypoxemia. Ba and FD at the time of ICU admission were strong independent predictors of mortality in the following 30 days. Levels of all complement activation markers were sustained throughout the patients' ICU stays, contrasting with the varying serum levels of IL-6, C-reactive protein, and ferritin. Severely ill COVID-19 patients have increased and persistent activation of complement, mediated strongly via the AP. Complement activation biomarkers may be valuable measures of severity of lung disease and the risk of mortality. Large-scale studies will reveal the relevance of these findings to thrombo-inflammation in acute and post-acute COVID-19.


Assuntos
COVID-19 , Biomarcadores , Ativação do Complemento , Mortalidade Hospitalar , Humanos , Hipóxia , SARS-CoV-2
2.
Blood ; 128(13): 1766-76, 2016 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-27338096

RESUMO

The complement system plays a key role in innate immunity, inflammation, and coagulation. The system is delicately balanced by negative regulatory mechanisms that modulate the host response to pathogen invasion and injury. The serpin, C1-esterase inhibitor (C1-INH), is the only known plasma inhibitor of C1s, the initiating serine protease of the classical pathway of complement. Like other serpin-protease partners, C1-INH interaction with C1s is accelerated by polyanions such as heparin. Polyphosphate (polyP) is a naturally occurring polyanion with effects on coagulation and complement. We recently found that polyP binds to C1-INH, prompting us to consider whether polyP acts as a cofactor for C1-INH interactions with its target proteases. We show that polyP dampens C1s-mediated activation of the classical pathway in a polymer length- and concentration-dependent manner by accelerating C1-INH neutralization of C1s cleavage of C4 and C2. PolyP significantly increases the rate of interaction between C1s and C1-INH, to an extent comparable to heparin, with an exosite on the serine protease domain of the enzyme playing a major role in this interaction. In a serum-based cell culture system, polyP significantly suppressed C4d deposition on endothelial cells, generated via the classical and lectin pathways. Moreover, polyP and C1-INH colocalize in activated platelets, suggesting that their interactions are physiologically relevant. In summary, like heparin, polyP is a naturally occurring cofactor for the C1s:C1-INH interaction and thus an important regulator of complement activation. The findings may provide novel insights into mechanisms underlying inflammatory diseases and the development of new therapies.


Assuntos
Proteínas Inativadoras do Complemento 1/metabolismo , Proteínas do Sistema Complemento/metabolismo , Polifosfatos/metabolismo , Sítios de Ligação , Plaquetas/imunologia , Plaquetas/metabolismo , Células Cultivadas , Proteína Inibidora do Complemento C1 , Complemento C1s/química , Complemento C1s/metabolismo , Complemento C2/metabolismo , Complemento C4/metabolismo , Via Clássica do Complemento , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Heparina/metabolismo , Humanos , Técnicas In Vitro , Polifosfatos/química
3.
Blood ; 123(5): 768-76, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24335501

RESUMO

Polyphosphate, synthesized by all cells, is a linear polymer of inorganic phosphate. When released into the circulation, it exerts prothrombotic and proinflammatory activities by modulating steps in the coagulation cascade. We examined the role of polyphosphate in regulating the evolutionarily related proteolytic cascade complement. In erythrocyte lysis assays, polyphosphate comprising more than 1000 phosphate units suppressed total hemolytic activity with a concentration to reduce maximal lysis to 50% that was 10-fold lower than with monophosphate. In the ion- and enzyme-independent terminal pathway complement assay, polyphosphate suppressed complement in a concentration- and size-dependent manner. Phosphatase-treated polyphosphate lost its ability to suppress complement, confirming that polymer integrity is required. Sequential addition of polyphosphate to the terminal pathway assay showed that polyphosphate interferes with complement only when added before formation of the C5b-7 complex. Physicochemical analyses using native gels, gel filtration, and differential scanning fluorimetry revealed that polyphosphate binds to and destabilizes C5b,6, thereby reducing the capacity of the membrane attack complex to bind to and lyse the target cell. In summary, we have added another function to polyphosphate in blood, demonstrating that it dampens the innate immune response by suppressing complement. These findings further establish the complex relationship between coagulation and innate immunity.


Assuntos
Complemento C5/antagonistas & inibidores , Proteínas do Sistema Complemento/metabolismo , Polifosfatos/metabolismo , Coagulação Sanguínea , Complemento C5/metabolismo , Eritrócitos/citologia , Eritrócitos/metabolismo , Hemólise , Humanos
5.
BMC Cancer ; 14: 113, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24555435

RESUMO

BACKGROUND: CD248 is a cell surface glycoprotein, highly expressed by stromal cells and fibroblasts of tumors and inflammatory lesions, but virtually undetectable in healthy adult tissues. CD248 promotes tumorigenesis, while lack of CD248 in mice confers resistance to tumor growth. Mechanisms by which CD248 is downregulated are poorly understood, hindering the development of anti-cancer therapies. METHODS: We sought to characterize the molecular mechanisms by which CD248 is downregulated by surveying its expression in different cells in response to cytokines and growth factors. RESULTS: Only transforming growth factor (TGFß) suppressed CD248 protein and mRNA levels in cultured fibroblasts and vascular smooth muscle cells in a concentration- and time-dependent manner. TGFß transcriptionally downregulated CD248 by signaling through canonical Smad2/3-dependent pathways, but not via mitogen activated protein kinases p38 or ERK1/2. Notably, cancer associated fibroblasts (CAF) and cancer cells were resistant to TGFß mediated suppression of CD248. CONCLUSIONS: The findings indicate that decoupling of CD248 regulation by TGFß may contribute to its tumor-promoting properties, and underline the importance of exploring the TGFß-CD248 signaling pathway as a potential therapeutic target for early prevention of cancer and proliferative disorders.


Assuntos
Antígenos CD/metabolismo , Antígenos de Neoplasias/metabolismo , Neoplasias/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Ativinas/metabolismo , Animais , Antígenos CD/genética , Antígenos de Neoplasias/genética , Proteína Morfogenética Óssea 2/metabolismo , Linhagem Celular Tumoral , Citocinas/farmacologia , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neoplasias/genética , Proteínas Serina-Treonina Quinases/metabolismo , Estabilidade de RNA/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
J Biol Chem ; 287(47): 39412-8, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23038252

RESUMO

Bacillus subtilis can perform chemotaxis toward all 20 L-amino acids normally found in proteins. Loss of a single chemoreceptor, McpC, was previously found to reduce chemotaxis to 19 of these amino acids. In this study, we investigated the amino acid-sensing mechanism of McpC. We show that McpC alone can support chemotaxis to 17 of these amino acids to varying degrees. Eleven amino acids were found to directly bind the amino-terminal sensing domain of McpC in vitro. Sequence analysis indicates that the McpC sensing domain exhibits a dual Per-Arnt-Sim (PAS) domain structure. Using this structure as a guide, we were able to isolate mutants that suggest that four amino acids (arginine, glutamine, lysine, and methionine) are sensed by an indirect mechanism. We identified four candidate binding lipoproteins associated with amino acid transporters that may function in indirect sensing: ArtP, GlnH, MetQ, and YckB. ArtP was found to bind arginine and lysine; GlnH, glutamine; MetQ, methionine; and YckB, tryptophan. In addition, we found that ArtP, MetQ, and YckB bind the sensing domain of McpC, suggesting that the three participate in the indirect sensing of arginine, lysine, methionine, and possibly tryptophan as well. Taken together, these results further our understanding of amino acid chemotaxis in B. subtilis and gain insight into how a single chemoreceptor is able to sense many amino acids.


Assuntos
Aminoácidos/metabolismo , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Lipoproteínas/metabolismo , Receptores de Superfície Celular/metabolismo , Aminoácidos/genética , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Lipoproteínas/genética , Estrutura Terciária de Proteína , Receptores de Superfície Celular/genética
7.
J Immunol ; 187(11): 5887-900, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22068232

RESUMO

When lymphocytes encounter APCs bearing cognate Ag, they spread across the surface of the APC to scan for additional Ags. This is followed by membrane contraction and the formation of Ag receptor microclusters that initiate the signaling reactions that lead to lymphocyte activation. Breakdown of the submembrane cytoskeleton is likely to be required for the cytoskeleton reorganization that drives cell spreading and for removing physical barriers that limit Ag receptor mobility. In this report, we show that Ag receptor signaling via the Rap GTPases promotes the dephosphorylation and activation of the actin-severing protein cofilin and that this results in increased severing of cellular actin filaments. Moreover, we show that this cofilin-mediated actin severing is critical for the changes in actin dynamics that drive B and T cell spreading, for the formation of BCR microclusters, and for the increased mobility of BCR microclusters within the plasma membrane after BCR engagement. Finally, using a model APC, we show that activation of this Rap-cofilin signaling module controls the amount of Ag that is gathered into BCR microclusters and that this is directly related to the magnitude of the resulting BCR signaling that is initiated during B cell-APC interactions. Thus, Rap-dependent activation of cofilin is critical for the early cytoskeletal changes and BCR reorganization that are involved in APC-dependent lymphocyte activation.


Assuntos
Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Quimiotaxia de Leucócito/imunologia , GTP Fosfo-Hidrolases/metabolismo , Família Multigênica , Receptores de Antígenos de Linfócitos B/metabolismo , Fatores de Despolimerização de Actina/imunologia , Actinas/imunologia , Animais , Apresentação de Antígeno/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Citoesqueleto/imunologia , Citoesqueleto/metabolismo , Células Dendríticas/imunologia , Imunofluorescência , GTP Fosfo-Hidrolases/imunologia , Immunoblotting , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos B/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transfecção
8.
IDCases ; 33: e01831, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37484827

RESUMO

Introduction: Talaromyces marneffei causes a systemic fungal infection, referred to as talaromycosis, in immunocompromised individuals. Talaromycosis is an AIDS (acquired immunodeficiency syndrome) defining illness for patients living in the Southeast Asian region. Here we present two rarely reported cases of pulmonary talaromycosis in Southern California in patients with active cancer, negative HIV status, and no prior travel history to endemic regions. Case description: Case 1: A 76-year-old male with a past medical history of emphysema and latent tuberculosis status post rifampin treatment, presented with a necrotic lung mass. He was diagnosed with squamous cell lung carcinoma and bronchoalveolar lavage cultures grew Talaromyces marneffei. He had no animal exposure or prior travel history to Asia. Due to a transfusion reaction to liposomal amphotericin (the mainstay of treatment), he required a transition to posaconazole. He was HIV-negative and expired due to underlying cancer and infection complications.Case2: A 63-year-old male with a past medical history of tuberculosis, diabetes, and cavitary pneumonia with bronchoscopy positive for Talaromyces presented with worsening back pain and was found to have multiple sites of poorly differentiated adenocarcinoma likely originating from gastric adenocarcinoma. He was HIV-negative and expired due to complications from underlying cancer and infection. Conclusion: We demonstrate that patients with pulmonary Talaromyces are becoming more prominent outside of endemic areas even in the setting of no prior travel. In addition, since patients with this infection are severely immunosuppressed, they require extensive workup for other comorbidities such as possible underlying cancer or tuberculosis.

9.
Am J Med Qual ; 38(3): 129-136, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37017283

RESUMO

Peer comparison feedback is a promising strategy for reducing opioid prescribing and opioid-related harms. Such comparisons may be particularly impactful among underestimating clinicians who do not perceive themselves as high prescribers relative to their peers. But peer comparisons could also unintentionally increase prescribing among overestimating clinicians who do not perceive themselves as lower prescribers than peers. The objective of this study was to assess if the impact of peer comparisons varied by clinicians' preexisting opioid prescribing self-perceptions. Subgroup analysis of a randomized trial of peer comparison interventions among emergency department and urgent care clinicians was used. Generalized mixed-effects models were used to assess whether the impact of peer comparisons, alone or combined with individual feedback, varied by underestimating or overestimating prescriber status. Underestimating and overestimating prescribers were defined as those who self-reported relative prescribing amounts that were lower and higher, respectively, than actual relative baseline amounts. The primary outcome was pills per opioid prescription. Among 438 clinicians, 54% (n = 236) provided baseline prescribing self-perceptions and were included in this analysis. Overall, 17% (n = 40) were underestimating prescribers whereas 5% (n = 11) were overestimating prescribers. Underestimating prescribers exhibited a differentially greater decrease in pills per prescription compared to nonunderestimating clinicians when receiving peer comparison feedback (1.7 pills, 95% CI, -3.2 to -0.2 pills) or combined peer and individual feedback (2.8 pills, 95% CI, -4.8 to -0.8 pills). In contrast, there were no differential changes in pills per prescription for overestimating versus nonoverestimating prescribers after receiving peer comparison (1.5 pills, 95% CI, -0.9 to 3.9 pills) or combined peer and individual feedback (3.0 pills, 95% CI, -0.3 to 6.2 pills). Peer comparisons were more impactful among clinicians who underestimated their prescribing compared to peers. By correcting inaccurate self-perceptions, peer comparison feedback can be an effective strategy for influencing opioid prescribing.


Assuntos
Analgésicos Opioides , Médicos , Humanos , Analgésicos Opioides/uso terapêutico , Retroalimentação , Padrões de Prática Médica , Serviço Hospitalar de Emergência
10.
Subst Abuse Treat Prev Policy ; 17(1): 25, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361228

RESUMO

BACKGROUND: The British Columbia (BC) Take-Home Naloxone (THN) program provides naloxone to people at risk of experiencing or witnessing an opioid overdose for use in reversing suspected overdose events. This study seeks to examine trends and correlates of individuals obtaining a THN kit in BC between 2017 and 2020. METHODS: Records of THN kits distributed between 2017 and 2020 were the primary source of data for this analysis. Frequency tables were used to describe characteristics of people obtaining kits from THN sites. Correlates of individuals obtaining a THN kit to replace a previous kit reported as used to reverse an overdose were assessed with multivariate logistic regression. RESULTS: Between January 1, 2017, and December 31, 2020, 240,606 THN kits were reported distributed by registered sites to members of the public, with 90,011 records indicating that a kit was obtained to replace a previous kit that had been used to reverse an overdose. There was a significant trend in increasing kits reported used by year (p < 0.01). The kit recipient's risk of overdose was a significant predictor of having reported using a THN kit, and the strength of the association was dependent on gender (Male: Adjusted odds ratio (AOR) 5.37 [95% confidence interval (CI) 5.08 - 5.67]; Female: AOR 8.35 [95% CI 7.90 - 8.82]; Trans and gender expansive: AOR 3.68 [95% CI 2.82 - 4.79]). CONCLUSIONS: Between 2017 and 2020, THN kits were used to reverse tens of thousands of overdose events in BC, with people at risk of overdose (i.e. people who use drugs [PWUD]) having greater odds of using a kit to reverse an overdose than those not at risk. Thus, PWUD are responsible for reversing the vast majority of overdoses. THN kits are being distributed to the people who use them most. However, additional strategies in conjunction with community-based naloxone distribution programs are needed to address the rising number of illicit drug toxicity deaths.


Assuntos
Overdose de Drogas , Drogas Ilícitas , Colúmbia Britânica/epidemiologia , Overdose de Drogas/tratamento farmacológico , Overdose de Drogas/epidemiologia , Feminino , Humanos , Masculino , Naloxona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico
11.
Health Aff (Millwood) ; 41(3): 424-433, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35254932

RESUMO

An initial opioid prescription with a greater number of pills is associated with a greater risk for future long-term opioid use, yet few interventions have reliably influenced individual clinicians' prescribing. Our objective was to evaluate the effect of feedback interventions for clinicians in reducing opioid prescribing. The interventions included feedback on a clinician's outlier prescribing (individual audit feedback), peer comparison, and both interventions combined. We conducted a four-arm factorial pragmatic cluster randomized trial at forty-eight emergency department (ED) and urgent care (UC) sites in the western US, including 263 ED and 175 UC clinicians with 294,962 patient encounters. Relative to usual care, there was a significant decrease in pills per prescription both for peer comparison feedback (-0.8) and for the combination of peer comparison and individual audit feedback (-1.2). This decrease was sustained during follow-up. There were no significant changes for individual audit feedback alone, and no interventions changed the proportion of encounters with an opioid prescription.


Assuntos
Analgésicos Opioides , Padrões de Prática Médica , Analgésicos Opioides/uso terapêutico , Serviço Hospitalar de Emergência , Retroalimentação , Humanos , Prescrição Inadequada , Grupo Associado
12.
Obesity (Silver Spring) ; 29(8): 1338-1346, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34111329

RESUMO

OBJECTIVE: The purpose of this study was to determine whether patients who discuss bariatric surgery with their providers are more likely to undergo the procedure and to lose weight. METHODS: A retrospective cohort study of adults with BMI ≥ 35 kg/m2 treated between 2000 and 2015 was conducted to analyze the relationship between a discussion of bariatric surgery in the first year after study entry and weight changes (primary outcome) and receipt of bariatric surgery (secondary outcome) over 2 years after study entry. Natural language processing was used to identify the documentation of bariatric surgery discussion in electronic provider notes. RESULTS: Out of 30,560 study patients, a total of 2,659 (8.7%) discussed bariatric surgery with their providers. The BMI of patients who discussed bariatric surgery decreased by 2.18 versus 0.21 for patients who did not (p < 0.001). In a multivariable analysis, patients who discussed bariatric surgery with their providers lost more weight (by 1.43 [change in BMI]; 95% CI: 1.29-1.57) and had greater odds (10.2; 95% CI: 9.0-11.6; p < 0.001) of undergoing bariatric surgery. CONCLUSIONS: Clinicians rarely discussed bariatric surgery with their patients. Patients who did have this discussion were more likely to lose weight and to undergo bariatric surgery.


Assuntos
Cirurgia Bariátrica , Obesidade Mórbida , Adulto , Humanos , Estudos Retrospectivos
13.
J Thromb Haemost ; 19(8): 1932-1947, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33830628

RESUMO

BACKGROUND: CD248 is a pro-inflammatory, transmembrane glycoprotein expressed by vascular smooth muscle cells (VSMC), monocytes/macrophages, and other cells of mesenchymal origin. Its distribution and properties are reminiscent of those of the initiator of coagulation, tissue factor (TF). OBJECTIVE: We examined whether CD248 also participates in thrombosis. METHODS: We evaluated the role of CD248 in coagulation using mouse models of vascular injury, and by assessing its functional interaction with the TF-factor VIIa (FVIIa)-factor X (FX) complex. RESULTS: The time to ferric chloride-induced occlusion of the carotid artery in CD248 knockout (KO) mice was significantly longer than in wild-type (WT) mice. In an inferior vena cava (IVC) stenosis model of thrombosis, lack of CD248 conferred relative resistance to thrombus formation compared to WT mice. Levels of circulating cells and coagulation factors, prothrombin time, activated partial thromboplastin time, and tail bleeding times were similar in both groups. Proximity ligation assays revealed that TF and CD248 are <40 nm apart, suggesting a potential functional relationship. Expression of CD248 by murine and human VSMCs, and by a monocytic cell line, significantly augmented TF-FVIIa-mediated activation of FX, which was not due to differential expression or encryption of TF, altered exposure of phosphatidylserine or differences in tissue factor pathway inhibitor expression. Rather, conformation-specific antibodies showed that CD248 induces allosteric changes in the TF-FVIIa-FX complex that facilitates FX activation by TF-FVIIa. CONCLUSION: CD248 is a newly uncovered protein partner and potential therapeutic target in the TF-FVIIa-FX macromolecular complex that modulates coagulation.


Assuntos
Tromboplastina , Trombose Venosa , Animais , Antígenos CD , Antígenos de Neoplasias , Fator VIIa , Humanos , Camundongos , Camundongos Knockout , Tempo de Protrombina
14.
J Hosp Med ; 15(10): 581-587, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32966202

RESUMO

BACKGROUND/OBJECTIVE: Risk-stratification tools for cardiac complications after noncardiac surgery based on preoperative risk factors are used to inform postoperative management. However, there is limited evidence on whether risk stratification can be improved by incorporating data collected intraoperatively, particularly for low-risk patients. METHODS: We conducted a retrospective cohort study of adults who underwent noncardiac surgery between 2014 and 2018 at four hospitals in the United States. Logistic regression with elastic net selection was used to classify in-hospital major adverse cardiovascular events (MACE) using preoperative and intraoperative data ("perioperative model"). We compared model performance to standard risk stratification tools and professional society guidelines that do not use intraoperative data. RESULTS: Of 72,909 patients, 558 (0.77%) experienced MACE. Those with MACE were older and less likely to be female. The perioperative model demonstrated an area under the receiver operating characteristic curve (AUC) of 0.88 (95% CI, 0.85-0.92). This was higher than the Lee Revised Cardiac Risk Index (RCRI) AUC of 0.79 (95% CI, 0.74-0.84; P < .001 for AUC comparison). There were more MACE complications in the top decile (n = 1,465) of the perioperative model's predicted risk compared with that of the RCRI model (n = 58 vs 43). Additionally, the perioperative model identified 2,341 of 7,597 (31%) patients as low risk who did not experience MACE but were recommended to receive postoperative biomarker testing by a risk factor-based guideline algorithm. CONCLUSIONS: Addition of intraoperative data to preoperative data improved prediction of cardiovascular complication outcomes after noncardiac surgery and could potentially help reduce unnecessary postoperative testing.


Assuntos
Cardiopatias , Complicações Pós-Operatórias , Feminino , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Estados Unidos
15.
JAMA Netw Open ; 2(12): e1916921, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31808922

RESUMO

Importance: Acute kidney injury (AKI) is one of the most common complications after noncardiac surgery. Yet current postoperative AKI risk stratification models have substantial limitations, such as limited use of perioperative data. Objective: To examine whether adding preoperative and intraoperative data is associated with improved prediction of noncardiac postoperative AKI. Design, Setting, and Participants: A prognostic study using logistic regression with elastic net selection, gradient boosting machine (GBM), and random forest approaches was conducted at 4 tertiary academic hospitals in the United States. A total of 42 615 hospitalized adults with serum creatinine measurements who underwent major noncardiac surgery between January 1, 2014, and April 30, 2018, were included in the study. Serum creatinine measurements from 365 days before and 7 days after surgery were used in this study. Main Outcomes and Measures: Postoperative AKI (defined by the Kidney Disease Improving Global Outcomes within 7 days after surgery) was the primary outcome. The area under the receiver operating characteristic curve (AUC) was used to assess discrimination. Results: Among 42 615 patients who underwent noncardiac surgery, the mean (SD) age was 57.9 (15.7) years, 23 943 (56.2%) were women, 27 857 (65.4%) were white, and the most frequent surgery types were orthopedic (15 718 [36.9%]), general (8808 [20.7%]), and neurologic (6564 [15.4%]). The rate of postoperative AKI was 10.1% (n = 4318). The progressive addition of clinical data improved model performance across all modeling approaches, with GBM providing the highest discrimination by AUC. In GBM models, the AUC increased from 0.712 (95% CI, 0.694-0.731) using prehospitalization variables to 0.804 (95% CI, 0.788-0.819) using preoperative variables (inclusive of prehospitalization variables) (P < .001 for AUC comparison). The AUC further increased to 0.817 (95% CI, 0.802-0.832) when adding intraoperative variables (P < .001 for comparison vs model using preoperative variables). However, the statistically significant improvements in discrimination did not appear to be clinically significant. In particular, the AKI rate among patients classified as high risk improved from 29.1% to 30.0%, a net of 15 patients were appropriately reclassified as high risk, and an additional 15 patients were appropriately reclassified as low risk. Conclusions and Relevance: The findings of the study suggest that electronic health record data may be used to accurately stratify patients at risk of perioperative AKI, but the modest improvements from adding intraoperative data should be weighed against challenges in using intraoperative data.


Assuntos
Injúria Renal Aguda/etiologia , Creatinina/sangue , Complicações Pós-Operatórias/etiologia , Medição de Risco/métodos , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Idoso , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/estatística & dados numéricos , Valor Preditivo dos Testes , Período Pré-Operatório , Prognóstico , Curva ROC , Fatores de Risco
16.
Stud Health Technol Inform ; 264: 223-227, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31437918

RESUMO

We tested the value of adding data from the operating room to models predicting in-hospital death. We assessed model performance using two metrics, the area under the receiver operating characteristic curve (AUROC) and the area under the precision-recall curve (AUPRC), to illustrate the differences in information they convey in the setting of class imbalance. Data was collected on 74,147 patients who underwent major noncardiac surgery and 112 unique features were extracted from electronic health records. Sets of features were incrementally added to models using logistic regression, naïve Bayes, random forest, and gradient boosted machine methods. AUROC increased as more features were added, but changes were small for some modeling approaches. In contrast, AUPRC, which reflects positive predicted value, exhibited improvements across all models. Using AUPRC highlighted the added value of intraoperative data, not seen consistently with AUROC, and that with class imbalance AUPRC may serve as the more clinically relevant criterion.


Assuntos
Registros Eletrônicos de Saúde , Área Sob a Curva , Teorema de Bayes , Humanos , Modelos Logísticos , Curva ROC
17.
EBioMedicine ; 44: 489-501, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31221584

RESUMO

BACKGROUND: A positive energy balance promotes white adipose tissue (WAT) expansion which is characterized by activation of a repertoire of events including hypoxia, inflammation and extracellular matrix remodelling. The transmembrane glycoprotein CD248 has been implicated in all these processes in different malignant and inflammatory diseases but its potential impact in WAT and metabolic disease has not been explored. METHODS: The role of CD248 in adipocyte function and glucose metabolism was evaluated by omics analyses in human WAT, gene knockdowns in human in vitro differentiated adipocytes and by adipocyte-specific and inducible Cd248 gene knockout studies in mice. FINDINGS: CD248 is upregulated in white but not brown adipose tissue of obese and insulin-resistant individuals. Gene ontology analyses showed that CD248 expression associated positively with pro-inflammatory/pro-fibrotic pathways. By combining data from several human cohorts with gene knockdown experiments in human adipocytes, our results indicate that CD248 acts as a microenvironmental sensor which mediates part of the adipose tissue response to hypoxia and is specifically perturbed in white adipocytes in the obese state. Adipocyte-specific and inducible Cd248 knockouts in mice, both before and after diet-induced obesity and insulin resistance/glucose intolerance, resulted in increased microvascular density as well as attenuated hypoxia, inflammation and fibrosis without affecting fat cell volume. This was accompanied by significant improvements in insulin sensitivity and glucose tolerance. INTERPRETATION: CD248 exerts detrimental effects on WAT phenotype and systemic glucose homeostasis which may be reversed by suppression of adipocyte CD248. Therefore, CD248 may constitute a target to treat obesity-associated co-morbidities.


Assuntos
Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Antígenos CD/genética , Antígenos de Neoplasias/genética , Metabolismo Energético/genética , Hipóxia/metabolismo , Paniculite/genética , Paniculite/metabolismo , Adulto , Animais , Modelos Animais de Doenças , Matriz Extracelular , Feminino , Fibrose , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Doenças Metabólicas/etiologia , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Obesidade/genética , Obesidade/metabolismo , Obesidade/patologia , Paniculite/patologia , Transdução de Sinais
18.
Health Serv Res ; 53(2): 1110-1136, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28295260

RESUMO

OBJECTIVE: To evaluate the prevalence of seven social factors using physician notes as compared to claims and structured electronic health records (EHRs) data and the resulting association with 30-day readmissions. STUDY SETTING: A multihospital academic health system in southeastern Massachusetts. STUDY DESIGN: An observational study of 49,319 patients with cardiovascular disease admitted from January 1, 2011, to December 31, 2013, using multivariable logistic regression to adjust for patient characteristics. DATA COLLECTION/EXTRACTION METHODS: All-payer claims, EHR data, and physician notes extracted from a centralized clinical registry. PRINCIPAL FINDINGS: All seven social characteristics were identified at the highest rates in physician notes. For example, we identified 14,872 patient admissions with poor social support in physician notes, increasing the prevalence from 0.4 percent using ICD-9 codes and structured EHR data to 16.0 percent. Compared to an 18.6 percent baseline readmission rate, risk-adjusted analysis showed higher readmission risk for patients with housing instability (readmission rate 24.5 percent; p < .001), depression (20.6 percent; p < .001), drug abuse (20.2 percent; p = .01), and poor social support (20.0 percent; p = .01). CONCLUSIONS: The seven social risk factors studied are substantially more prevalent than represented in administrative data. Automated methods for analyzing physician notes may enable better identification of patients with social needs.


Assuntos
Documentação/estatística & dados numéricos , Registros Eletrônicos de Saúde/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Médicos , Acidentes por Quedas/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Depressão/epidemiologia , Feminino , Pessoas Mal Alojadas/estatística & dados numéricos , Humanos , Revisão da Utilização de Seguros/estatística & dados numéricos , Modelos Logísticos , Masculino , Massachusetts , Pessoa de Meia-Idade , Processamento de Linguagem Natural , Fatores de Risco , Fatores Sexuais , Apoio Social , Fatores Socioeconômicos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Fatores de Tempo , Adulto Jovem
19.
Spine J ; 18(11): 2025-2032, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29679730

RESUMO

BACKGROUND CONTEXT: Revision posterior decompression and fusion surgery for patients with symptomatic adjacent segment degeneration (ASD) is associated with significant morbidity and is technically challenging. The use of a stand-alone lateral lumbar interbody fusion (LLIF) in patients with symptomatic ASD may prevent many of the complications associated with revision posterior surgery. PURPOSE: The objective of this study was to assess the clinical and radiographic outcomes of patients who underwent stand-alone LLIF for symptomatic ASD. STUDY DESIGN: This is a retrospective case series. PATIENT SAMPLE: We retrospectively reviewed patients with a prior posterior instrumented fusion who underwent a subsequent stand-alone LLIF for ASD by a single surgeon. All patients had at least 18 months of follow-up. Patients were diagnosed with symptomatic ASD if they had a previous lumbar fusion with the subsequent development of back pain, neurogenic claudication, or lower extremity radiculopathy in the setting of imaging, which demonstrated stenosis, spondylolisthesis, kyphosis, or scoliosis at the adjacent level. OUTCOME MEASURES: Patient-reported outcomes were obtained at preoperative and final follow-up visits using the Oswestry Disability Index [ODI], visual analog scale (VAS)-back, and VAS-leg. Radiographic parameters were measured, including segmental and overall lordoses, pelvic incidence-lumbar lordosis mismatch, coronal alignment, and intervertebral disc height. METHODS: Clinical and radiographic outcomes were compared between preoperative and final follow-up using paired t tests. RESULTS: Twenty-five patients met inclusion criteria. The mean age was 62.0±11.3 years. The average follow-up was 34.8±22.4 months. Fifteen (60%) underwent stand-alone LLIF surgery for radicular leg pain, 7 (28%) for symptoms of claudication, and 25 (100.0%) for severe back pain. Oswestry Disability Index scores significantly improved from preoperative values (46.6±16.4) to final follow-up (30.4±16.8, p=.002). Visual analog scale-back (preop 8.4±1.0, postop 3.2±1.9; p<.001), and VAS-leg (preop 3.6±3.4, postop 1.9±2.6; p<.001) scores significantly improved following surgery. Segmental and regional lordoses, as well as intervertebral disc height, significantly improved (p<.001) and remained stable (p=.004) by the surgery. Pelvic incidence-lumbar lordosis mismatch significantly improved at the first postoperative visit (p=.029) and was largely maintained at the most recent follow-up (p=.45). Six patients suffered from new-onset thigh weakness following LLIF surgery, but all showed complete resolution within 6 weeks. Three patients required subsequent additional surgeries, all of which were revised to include posterior instrumentation. CONCLUSIONS: Stand-alone LLIF is a safe and effective approach with low morbidity and acceptable complication rates for patients with symptomatic ASD following a previous lumbar fusion.


Assuntos
Descompressão Cirúrgica/métodos , Degeneração do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Complicações Pós-Operatórias/cirurgia , Reoperação/métodos , Fusão Vertebral/métodos , Adulto , Idoso , Descompressão Cirúrgica/efeitos adversos , Feminino , Humanos , Disco Intervertebral/cirurgia , Masculino , Pessoa de Meia-Idade , Fusão Vertebral/efeitos adversos
20.
West J Nurs Res ; 39(1): 147-165, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27628125

RESUMO

This study developed an innovative natural language processing algorithm to automatically identify heart failure (HF) patients with ineffective self-management status (in the domains of diet, physical activity, medication adherence, and adherence to clinician appointments) from narrative discharge summary notes. We also analyzed the association between self-management status and preventable 30-day hospital readmissions. Our natural language system achieved relatively high accuracy ( F-measure = 86.3%; precision = 95%; recall = 79.2%) on a testing sample of 300 notes annotated by two human reviewers. In a sample of 8,901 HF patients admitted to our healthcare system, 14.4% ( n = 1,282) had documentation of ineffective HF self-management. Adjusted regression analyses indicated that presence of any skill-related self-management deficit (odds ratio [OR] = 1.3, 95% confidence interval [CI] = [1.1, 1.6]) and non-specific ineffective self-management (OR = 1.5, 95% CI = [1.2, 2]) was significantly associated with readmissions. We have demonstrated the feasibility of identifying ineffective HF self-management from electronic discharge summaries with natural language processing.

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