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1.
Artículo en Inglés | MEDLINE | ID: mdl-37592963

RESUMEN

Objective: To determine the prevalence of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) IgG nucleocapsid (N) antibodies among healthcare personnel (HCP) with no prior history of COVID-19 and to identify factors associated with seropositivity. Design: Prospective cohort study. Setting: An academic, tertiary-care hospital in St. Louis, Missouri. Participants: The study included 400 HCP aged ≥18 years who potentially worked with coronavirus disease 2019 (COVID-19) patients and had no known history of COVID-19; 309 of these HCP also completed a follow-up visit 70-160 days after enrollment. Enrollment visits took place between September and December 2020. Follow-up visits took place between December 2020 and April 2021. Methods: At each study visit, participants underwent SARS-CoV-2 IgG N-antibody testing using the Abbott SARS-CoV-2 IgG assay and completed a survey providing information about demographics, job characteristics, comorbidities, symptoms, and potential SARS-CoV-2 exposures. Results: Participants were predominately women (64%) and white (79%), with median age of 34.5 years (interquartile range [IQR], 30-45). Among the 400 HCP, 18 (4.5%) were seropositive for IgG N-antibodies at enrollment. Also, 34 (11.0%) of 309 were seropositive at follow-up. HCP who reported having a household contact with COVID-19 had greater likelihood of seropositivity at both enrollment and at follow-up. Conclusions: In this cohort of HCP during the first wave of the COVID-19 pandemic, ∼1 in 20 had serological evidence of prior, undocumented SARS-CoV-2 infection at enrollment. Having a household contact with COVID-19 was associated with seropositivity.

2.
Infect Control Hosp Epidemiol ; 44(9): 1472-1480, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36924218

RESUMEN

OBJECTIVE: Dental healthcare personnel (DHCP) are at high risk of exposure to coronavirus disease 2019 (COVID-19). We sought to identify how DHCP changed their use of personal protective equipment (PPE) as a result of the COVID-19 pandemic, and to pilot an educational video designed to improve knowledge of proper PPE use. DESIGN: The study comprised 2 sets of semistructured qualitative interviews. SETTING: The study was conducted in 8 dental clinics in a Midwestern metropolitan area. PARTICIPANTS: In total, 70 DHCP participated in the first set of interviews; 63 DHCP participated in the second set of interviews. METHODS: In September-November 2020 and March-October 2021, we conducted 2 sets of semistructured interviews: (1) PPE use in the dental community during COVID-19, and (2) feedback on the utility of an educational donning and doffing video. RESULTS: Overall, 86% of DHCP reported having prior training. DHCP increased the use of PPE during COVID-19, specifically N95 respirators and face shields. DHCP reported real-world challenges to applying infection control methods, often resulting in PPE modification and reuse. DHCP reported double masking and sterilization methods to extend N95 respirator use. Additional challenges to PPE included shortages, comfort or discomfort, and compatibility with specialty dental equipment. DHCP found the educational video helpful and relevant to clinical practice. Fewer than half of DHCP reported exposure to a similar video. CONCLUSIONS: DHCP experienced significant challenges related to PPE access and routine use in dental clinics during the COVID-19 pandemic. An educational video improved awareness and uptake of appropriate PPE use among DHCP.


Asunto(s)
COVID-19 , Humanos , COVID-19/prevención & control , Pandemias/prevención & control , Equipo de Protección Personal , Control de Infecciones/métodos , Instituciones de Salud , Personal de Salud
3.
Artículo en Inglés | MEDLINE | ID: mdl-36483341

RESUMEN

In this prospective, longitudinal study, we examined the risk factors for severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection among a cohort of chronic hemodialysis (HD) patients and healthcare personnel (HCPs) over a 6-month period. The risk of SARS-CoV-2 infection among HD patients and HCPs was consistently associated with a household member having SARS-CoV-2 infection.

4.
Artículo en Inglés | MEDLINE | ID: mdl-36483363

RESUMEN

In a prospective cohort of healthcare personnel (HCP), we measured severe acute respiratory syndrome coronavirus virus 2 (SARS-CoV-2) nucleocapsid IgG antibodies after SARS-CoV-2 infection. Among 79 HCP, 68 (86%) were seropositive 14-28 days after their positive PCR test, and 54 (77%) of 70 were seropositive at the 70-180-day follow-up. Many seropositive HCP (95%) experienced an antibody decline by the second visit.

5.
Int J Clin Pract ; 2022: 7786174, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36540065

RESUMEN

Methods: Using information from electronic health records in Germany and the United Kingdom (UK) in a common data model, we followed adults with ≥2 low-dose aspirin prescriptions (75-100 mg) during 2007-2018 for up to 10 years. Included individuals had no low-dose aspirin prescriptions in the year before the follow-up started (date of first low-dose aspirin prescription) and ≥12 months' observation. Adherence was determined using the medication possession ratio (MPR), and persistence was defined as continuous treatment disregarding gaps between prescriptions of <60 days; analyses were undertaken according to indication (primary/secondary CVD prevention). Results: We identified 144,717 low-dose aspirin users from Germany and 190,907 from the UK. Among patients with 5-10 years' follow-up, median adherence among secondary CVD prevention users was 60% in Germany and 75% in the UK. Among primary prevention users, median adherence was 50% for both countries. Persistence among secondary CVD prevention users was 58.3% at 2 years, 47.0% at 5 years, 35.2% at 10 years (Germany), and 67.5% at 2 years, 58.0% at 5 years, and 46.8% at 10 years (UK). Among primary CVD prevention users, persistence was 52.8% at 2 years, 41.6% at 5 years, 32.1% at 10 years (Germany), 56.3% at 2 years, 45.4% at 5 years, and 33.8% at 10 years (UK). Conclusions: Long-term adherence and persistence to low-dose aspirin are suboptimal; efforts for improvement could translate into a lower CVD burden in the general population.


Asunto(s)
Enfermedades Cardiovasculares , Adulto , Humanos , Enfermedades Cardiovasculares/prevención & control , Enfermedades Cardiovasculares/tratamiento farmacológico , Estudios de Cohortes , Aspirina/uso terapéutico , Reino Unido/epidemiología , Alemania/epidemiología , Cumplimiento de la Medicación
6.
Ann Intern Med ; 175(11): 1515-1524, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36315950

RESUMEN

BACKGROUND: Current guidelines recommend using direct oral anticoagulants (DOACs) over warfarin in patients with atrial fibrillation (AF), but head-to-head trial data do not exist to guide the choice of DOAC. OBJECTIVE: To do a large-scale comparison between all DOACs (apixaban, dabigatran, edoxaban, and rivaroxaban) in routine clinical practice. DESIGN: Multinational population-based cohort study. SETTING: Five standardized electronic health care databases, which covered 221 million people in France, Germany, the United Kingdom, and the United States. PARTICIPANTS: Patients who were newly diagnosed with AF from 2010 through 2019 and received a new DOAC prescription. MEASUREMENTS: Database-specific hazard ratios (HRs) of ischemic stroke or systemic embolism, intracranial hemorrhage (ICH), gastrointestinal bleeding (GIB), and all-cause mortality between DOACs were estimated using a Cox regression model stratified by propensity score and pooled using a random-effects model. RESULTS: A total of 527 226 new DOAC users met the inclusion criteria (apixaban, n = 281 320; dabigatran, n = 61 008; edoxaban, n = 12 722; and rivaroxaban, n = 172 176). Apixaban use was associated with lower risk for GIB than use of dabigatran (HR, 0.81 [95% CI, 0.70 to 0.94]), edoxaban (HR, 0.77 [CI, 0.66 to 0.91]), or rivaroxaban (HR, 0.72 [CI, 0.66 to 0.79]). No substantial differences were observed for other outcomes or DOAC-DOAC comparisons. The results were consistent for patients aged 80 years or older. Consistent associations between lower GIB risk and apixaban versus rivaroxaban were observed among patients receiving the standard dose (HR, 0.72 [CI, 0.64 to 0.82]), those receiving a reduced dose (HR, 0.68 [CI, 0.61 to 0.77]), and those with chronic kidney disease (HR, 0.68 [CI, 0.59 to 0.77]). LIMITATION: Residual confounding is possible. CONCLUSION: Among patients with AF, apixaban use was associated with lower risk for GIB and similar rates of ischemic stroke or systemic embolism, ICH, and all-cause mortality compared with dabigatran, edoxaban, and rivaroxaban. This finding was consistent for patients aged 80 years or older and those with chronic kidney disease, who are often underrepresented in clinical trials. PRIMARY FUNDING SOURCE: None.


Asunto(s)
Anticoagulantes , Fibrilación Atrial , Humanos , Administración Oral , Anticoagulantes/efectos adversos , Fibrilación Atrial/tratamiento farmacológico , Estudios de Cohortes , Dabigatrán/efectos adversos , Embolia/epidemiología , Embolia/etiología , Embolia/prevención & control , Accidente Cerebrovascular Isquémico , Insuficiencia Renal Crónica/complicaciones , Rivaroxabán/efectos adversos , Estados Unidos , Ensayos Clínicos como Asunto
7.
J Am Dent Assoc ; 153(11): 1070-1077.e1, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36175202

RESUMEN

BACKGROUND: Dental health care personnel (DHCP) may be at increased risk of exposure to severe acute respiratory syndrome coronavirus 2, the virus that causes COVID-19, as well as other clinically important pathogens. Proper use of personal protective equipment (PPE) reduces occupational exposure to pathogens. The authors performed an assessment of PPE donning and doffing practices among DHCP, using a fluorescent marker as a surrogate for pathogen transmission. METHODS: Participants donned PPE (that is, disposable gown, gloves, face mask, and eye protection) and the fluorescent marker was applied to their palms and abdomen. DHCP then doffed PPE according to their usual practices. The donning and doffing processes were video recorded, areas of fluorescence were noted, and protocol deviations were assessed. Statistical analyses included frequency, type, and descriptions of protocol deviations and factors associated with fluorescence. RESULTS: Seventy DHCP were enrolled. The donning and doffing steps with the highest frequency of protocol deviations were hand hygiene (66% of donning and 78% of doffing observations involved a deviation) and disposable gown use (63% of donning and 60% of doffing observations involved a deviation). Fluorescence was detected on 69% of DHCP after doffing, most frequently on hands. An increasing number of protocol deviations was significantly associated with increased risk of fluorescence. DHCP with a gown doffing deviation, excluding doffing out of order, were more likely to have fluorescence detected. CONCLUSIONS: DHCP self-contamination was common with both donning and doffing PPE. PRACTICAL IMPLICATIONS: Proper use of PPE is an important component of occupational health.


Asunto(s)
COVID-19 , Equipo de Protección Personal , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Personal de Salud , SARS-CoV-2 , Atención a la Salud
8.
Int J Clin Pract ; 2022: 6707985, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35685531

RESUMEN

Background: Data directly comparing trends in the use of different oral anticoagulants (OACs) among patients with atrial fibrillation (AF) from different countries are limited. We addressed this using a large-scale network cohort study in the United States (US), Belgium, France, Germany, and the United Kingdom (UK). Methods: We used nine databases (claims or electronic health records) that had been converted into the Observational Medical Outcomes Partnership Common Data Model with analysis performed using open-source analytical tools. We identified adults with AF and a first OAC prescription, either vitamin K antagonist (VKA) or direct oral anticoagulant (DOAC), from 2010 to 2017. We described time trends in use, continuation, and switching. Results: In 2010, 87.5%-99.8% of patients started on a VKA. By 2017, the majority started on a DOAC: 87.0% (US), 88.3% (Belgium), 93.1% (France), 88.4% (Germany), and 86.1%-86.7% (UK). In the UK, DOACs became the most common starting OAC in 2015, 2-3 years later than elsewhere. Apixaban was the most common starting OAC by 2017, 50.2%-57.8% (US), 31.4% (Belgium), 45.9% (France), 39.5% (Germany), and 49.8%-50.5% (UK), followed by rivaroxaban, 24.8%-32.5% (US), 25.7% (Belgium), 38.4% (France), 24.9% (Germany), and 30.2%-31.2% (UK). Long-term treatment was less common in the US than in Europe, especially the UK. A minority of patients switched from their index OAC in the short and long term. Conclusions: From 2010 to 2017, VKA use had significantly declined and DOAC use had significantly increased in the US and Europe. Apixaban was the most prescribed OAC in 2017, followed by rivaroxaban.


Asunto(s)
Fibrilación Atrial , Accidente Cerebrovascular , Administración Oral , Adulto , Anticoagulantes/uso terapéutico , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/epidemiología , Estudios de Cohortes , Dabigatrán/uso terapéutico , Francia , Humanos , Rivaroxabán/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Estados Unidos/epidemiología
9.
Semin Arthritis Rheum ; 56: 152050, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35728447

RESUMEN

BACKGROUND: Identification of rheumatoid arthritis (RA) patients at high risk of adverse health outcomes remains a major challenge. We aimed to develop and validate prediction models for a variety of adverse health outcomes in RA patients initiating first-line methotrexate (MTX) monotherapy. METHODS: Data from 15 claims and electronic health record databases across 9 countries were used. Models were developed and internally validated on Optum® De-identified Clinformatics® Data Mart Database using L1-regularized logistic regression to estimate the risk of adverse health outcomes within 3 months (leukopenia, pancytopenia, infection), 2 years (myocardial infarction (MI) and stroke), and 5 years (cancers [colorectal, breast, uterine] after treatment initiation. Candidate predictors included demographic variables and past medical history. Models were externally validated on all other databases. Performance was assessed using the area under the receiver operator characteristic curve (AUC) and calibration plots. FINDINGS: Models were developed and internally validated on 21,547 RA patients and externally validated on 131,928 RA patients. Models for serious infection (AUC: internal 0.74, external ranging from 0.62 to 0.83), MI (AUC: internal 0.76, external ranging from 0.56 to 0.82), and stroke (AUC: internal 0.77, external ranging from 0.63 to 0.95), showed good discrimination and adequate calibration. Models for the other outcomes showed modest internal discrimination (AUC < 0.65) and were not externally validated. INTERPRETATION: We developed and validated prediction models for a variety of adverse health outcomes in RA patients initiating first-line MTX monotherapy. Final models for serious infection, MI, and stroke demonstrated good performance across multiple databases and can be studied for clinical use. FUNDING: This activity under the European Health Data & Evidence Network (EHDEN) has received funding from the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement No 806968. This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation programme and EFPIA.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Accidente Cerebrovascular , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Estudios de Cohortes , Humanos , Metotrexato/uso terapéutico , Evaluación de Resultado en la Atención de Salud , Accidente Cerebrovascular/etiología
11.
Front Cell Infect Microbiol ; 12: 804175, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35186791

RESUMEN

Immunocompromised adults can have prolonged acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive RT-PCR results, long after the initial diagnosis of coronavirus disease 2019 (COVID-19). This study aimed to determine if SARS-CoV-2 virus can be recovered in viral cell culture from immunocompromised adults with persistently positive SARS-CoV-2 RT-PCR tests. We obtained 20 remnant SARS-CoV-2 PCR positive nasopharyngeal swabs from 20 immunocompromised adults with a positive RT-PCR test ≥14 days after the initial positive test. The patients' 2nd test samples underwent SARS-CoV-2 antigen testing, and culture with Vero-hACE2-TMPRSS2 cells. Viral RNA and cultivable virus were recovered from the cultured cells after qRT-PCR and plaque assays. Of 20 patients, 10 (50%) had a solid organ transplant and 5 (25%) had a hematologic malignancy. For most patients, RT-PCR Ct values increased over time. There were 2 patients with positive viral cell cultures; one patient had chronic lymphocytic leukemia treated with venetoclax and obinutuzumab who had a low viral titer of 27 PFU/mL. The second patient had marginal zone lymphoma treated with bendamustine and rituximab who had a high viral titer of 2 x 106 PFU/mL. Most samples collected ≥7 days after an initial positive SARS-CoV-2 RT-PCR had negative viral cell cultures. The 2 patients with positive viral cell cultures had hematologic malignancies treated with chemotherapy and B cell depleting therapy. One patient had a high concentration titer of cultivable virus. Further data are needed to determine risk factors for persistent viral shedding and methods to prevent SARS-CoV-2 transmission from immunocompromised hosts.


Asunto(s)
COVID-19 , SARS-CoV-2 , Técnicas de Cultivo de Célula , Humanos , Huésped Inmunocomprometido , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
13.
Rheumatology (Oxford) ; 60(7): 3222-3234, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33367863

RESUMEN

OBJECTIVES: Concern has been raised in the rheumatology community regarding recent regulatory warnings that HCQ used in the coronavirus disease 2019 pandemic could cause acute psychiatric events. We aimed to study whether there is risk of incident depression, suicidal ideation or psychosis associated with HCQ as used for RA. METHODS: We performed a new-user cohort study using claims and electronic medical records from 10 sources and 3 countries (Germany, UK and USA). RA patients ≥18 years of age and initiating HCQ were compared with those initiating SSZ (active comparator) and followed up in the short (30 days) and long term (on treatment). Study outcomes included depression, suicide/suicidal ideation and hospitalization for psychosis. Propensity score stratification and calibration using negative control outcomes were used to address confounding. Cox models were fitted to estimate database-specific calibrated hazard ratios (HRs), with estimates pooled where I2 <40%. RESULTS: A total of 918 144 and 290 383 users of HCQ and SSZ, respectively, were included. No consistent risk of psychiatric events was observed with short-term HCQ (compared with SSZ) use, with meta-analytic HRs of 0.96 (95% CI 0.79, 1.16) for depression, 0.94 (95% CI 0.49, 1.77) for suicide/suicidal ideation and 1.03 (95% CI 0.66, 1.60) for psychosis. No consistent long-term risk was seen, with meta-analytic HRs of 0.94 (95% CI 0.71, 1.26) for depression, 0.77 (95% CI 0.56, 1.07) for suicide/suicidal ideation and 0.99 (95% CI 0.72, 1.35) for psychosis. CONCLUSION: HCQ as used to treat RA does not appear to increase the risk of depression, suicide/suicidal ideation or psychosis compared with SSZ. No effects were seen in the short or long term. Use at a higher dose or for different indications needs further investigation. TRIAL REGISTRATION: Registered with EU PAS (reference no. EUPAS34497; http://www.encepp.eu/encepp/viewResource.htm? id=34498). The full study protocol and analysis source code can be found at https://github.com/ohdsi-studies/Covid19EstimationHydroxychloroquine2.


Asunto(s)
Antirreumáticos/efectos adversos , Tratamiento Farmacológico de COVID-19 , Depresión/inducido químicamente , Depresión/epidemiología , Hidroxicloroquina/efectos adversos , Psicosis Inducidas por Sustancias/epidemiología , Psicosis Inducidas por Sustancias/etiología , Ideación Suicida , Suicidio/estadística & datos numéricos , Adolescente , Adulto , Anciano , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Estudios de Cohortes , Femenino , Alemania , Humanos , Hidroxicloroquina/uso terapéutico , Masculino , Persona de Mediana Edad , Medición de Riesgo , Reino Unido , Estados Unidos , Adulto Joven
14.
Lancet Rheumatol ; 2(11): e698-e711, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32864627

RESUMEN

BACKGROUND: Hydroxychloroquine, a drug commonly used in the treatment of rheumatoid arthritis, has received much negative publicity for adverse events associated with its authorisation for emergency use to treat patients with COVID-19 pneumonia. We studied the safety of hydroxychloroquine, alone and in combination with azithromycin, to determine the risk associated with its use in routine care in patients with rheumatoid arthritis. METHODS: In this multinational, retrospective study, new user cohort studies in patients with rheumatoid arthritis aged 18 years or older and initiating hydroxychloroquine were compared with those initiating sulfasalazine and followed up over 30 days, with 16 severe adverse events studied. Self-controlled case series were done to further establish safety in wider populations, and included all users of hydroxychloroquine regardless of rheumatoid arthritis status or indication. Separately, severe adverse events associated with hydroxychloroquine plus azithromycin (compared with hydroxychloroquine plus amoxicillin) were studied. Data comprised 14 sources of claims data or electronic medical records from Germany, Japan, the Netherlands, Spain, the UK, and the USA. Propensity score stratification and calibration using negative control outcomes were used to address confounding. Cox models were fitted to estimate calibrated hazard ratios (HRs) according to drug use. Estimates were pooled where the I 2 value was less than 0·4. FINDINGS: The study included 956 374 users of hydroxychloroquine, 310 350 users of sulfasalazine, 323 122 users of hydroxychloroquine plus azithromycin, and 351 956 users of hydroxychloroquine plus amoxicillin. No excess risk of severe adverse events was identified when 30-day hydroxychloroquine and sulfasalazine use were compared. Self-controlled case series confirmed these findings. However, long-term use of hydroxychloroquine appeared to be associated with increased cardiovascular mortality (calibrated HR 1·65 [95% CI 1·12-2·44]). Addition of azithromycin appeared to be associated with an increased risk of 30-day cardiovascular mortality (calibrated HR 2·19 [95% CI 1·22-3·95]), chest pain or angina (1·15 [1·05-1·26]), and heart failure (1·22 [1·02-1·45]). INTERPRETATION: Hydroxychloroquine treatment appears to have no increased risk in the short term among patients with rheumatoid arthritis, but in the long term it appears to be associated with excess cardiovascular mortality. The addition of azithromycin increases the risk of heart failure and cardiovascular mortality even in the short term. We call for careful consideration of the benefit-risk trade-off when counselling those on hydroxychloroquine treatment. FUNDING: National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, NIHR Senior Research Fellowship programme, US National Institutes of Health, US Department of Veterans Affairs, Janssen Research and Development, IQVIA, Korea Health Industry Development Institute through the Ministry of Health and Welfare Republic of Korea, Versus Arthritis, UK Medical Research Council Doctoral Training Partnership, Foundation Alfonso Martin Escudero, Innovation Fund Denmark, Novo Nordisk Foundation, Singapore Ministry of Health's National Medical Research Council Open Fund Large Collaborative Grant, VINCI, Innovative Medicines Initiative 2 Joint Undertaking, EU's Horizon 2020 research and innovation programme, and European Federation of Pharmaceutical Industries and Associations.

15.
PLoS One ; 15(1): e0226718, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31910437

RESUMEN

BACKGROUND AND PURPOSE: Hemorrhagic transformation (HT) after cerebral infarction is a complex and multifactorial phenomenon in the acute stage of ischemic stroke, and often results in a poor prognosis. Thus, identifying risk factors and making an early prediction of HT in acute cerebral infarction contributes not only to the selections of therapeutic regimen but also, more importantly, to the improvement of prognosis of acute cerebral infarction. The purpose of this study was to develop and validate a model to predict a patient's risk of HT within 30 days of initial ischemic stroke. METHODS: We utilized a retrospective multicenter observational cohort study design to develop a Lasso Logistic Regression prediction model with a large, US Electronic Health Record dataset which structured to the Observational Medical Outcomes Partnership (OMOP) Common Data Model (CDM). To examine clinical transportability, the model was externally validated across 10 additional real-world healthcare datasets include EHR records for patients from America, Europe and Asia. RESULTS: In the database the model was developed, the target population cohort contained 621,178 patients with ischemic stroke, of which 5,624 patients had HT within 30 days following initial ischemic stroke. 612 risk predictors, including the distance a patient travels in an ambulance to get to care for a HT, were identified. An area under the receiver operating characteristic curve (AUC) of 0.75 was achieved in the internal validation of the risk model. External validation was performed across 10 databases totaling 5,515,508 patients with ischemic stroke, of which 86,401 patients had HT within 30 days following initial ischemic stroke. The mean external AUC was 0.71 and ranged between 0.60-0.78. CONCLUSIONS: A HT prognostic predict model was developed with Lasso Logistic Regression based on routinely collected EMR data. This model can identify patients who have a higher risk of HT than the population average with an AUC of 0.78. It shows the OMOP CDM is an appropriate data standard for EMR secondary use in clinical multicenter research for prognostic prediction model development and validation. In the future, combining this model with clinical information systems will assist clinicians to make the right therapy decision for patients with acute ischemic stroke.


Asunto(s)
Isquemia Encefálica/complicaciones , Hemorragia Cerebral/diagnóstico , Modelos Estadísticos , Medición de Riesgo/métodos , Accidente Cerebrovascular/complicaciones , Hemorragia Cerebral/etiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Estudios Retrospectivos , Factores de Riesgo
16.
Nano Lett ; 15(3): 2006-10, 2015 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-25692995

RESUMEN

By means of hybrid DFT calculations and the deformation potential approximation, we show that bilayer phosphorene under slight compression perpendicular to its surface exhibits extraordinary room temperature electron mobility of order 7 × 10(4) cm(2) V(-1) s(-1). This is approximately 2 orders of magnitude higher than is widely reported for ground state phosphorenes and is the result of the emergence of a new conduction band minimum that is decoupled from the in-plane acoustic phonons that dominate carrier scattering.

17.
Nano Lett ; 14(8): 4607-14, 2014 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-24992160

RESUMEN

Passivated phosphorene nanoribbons, armchair (a-PNR), diagonal (d-PNR), and zigzag (z-PNR), were investigated using density functional theory. Z-PNRs demonstrate the greatest quantum size effect, tuning the bandgap from 1.4 to 2.6 eV when the width is reduced from 26 to 6 Å. Strain effectively tunes charge carrier transport, leading to a sudden increase in electron effective mass at +8% strain for a-PNRs or hole effective mass at +3% strain for z-PNRs, differentiating the (mh*/me*) ratio by an order of magnitude in each case. Straining of d-PNRs results in a direct to indirect band gap transition at either -7% or +5% strain and therein creates degenerate energy valleys with potential applications for valleytronics and/or photocatalysis.

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