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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117445, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31382229

RESUMO

Quantum cascade laser (QCL) based photoacoustic spectroscopic technique has been developed for detection of hazardous molecules contaminants/adsorbed on surfaces such as plastic and cloth from short standoff distances. The laser source and detection system is integrated together in a single unit. Spectra were recorded for traces of various molecules in mid-infrared spectral band (1130-1430 cm-1) from distance of 0.5 m. Pulsed quantum cascade laser source, modulated at 25 kHz and 42 kHz frequency was used to detect molecular species adsorbed on surfaces of cloth and plastic. Ultrasonic microphones operating at 25 and 42 kHz resonant frequencies were used as detectors. The photoacoustic spectra of hazardous chemicals, explosive materials and bio-chemicals such as acetic acid, PETN (pentaerythritol tetranitrate), DPA (dipicolinic acid) in very low quantities were recorded. Sensitivities of 5 and 10 µg/cm2 of these analytes were achieved with frequencies of 25 and 42 kHz respectively at distance of 0.5 m. In the present technique there was no interference of audio frequency (20 Hz to 20 kHz) and bright sunlight. The technique can be applied for screening of suspicious objects for homeland security and forensic applications. The present spectroscopic technique can be developed in man portable standalone product.

3.
J Am Coll Cardiol ; 74(15): 1924-1925, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31601372
4.
JAMA Neurol ; 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31524941

RESUMO

Importance: The COMPASS (Cardiovascular Outcomes for People Using Anticoagulation Strategies) randomized clinical trial was stopped early owing to the efficacy of low-dose rivaroxaban plus aspirin in preventing major cardiovascular events. The main reason for early trial termination was the effect of combination therapy on reducing ischemic strokes. Objective: To analyze the association between low-dose rivaroxaban with or without aspirin and different ischemic stroke subtypes. Design, Setting, and Participants: This is a secondary analysis of a multicenter, double-blind, randomized, placebo-controlled study that was performed in 33 countries from March 12, 2013, to May 10, 2016. Patients with stable atherosclerotic vascular disease were eligible, and a total of 27 395 participants were randomized and followed up to February 6, 2017. All first ischemic strokes and uncertain strokes that occurred by this date were adjudicated using TOAST (Trial of Org 10172 in Acute Stroke Treatment) criteria. The analysis of ischemic stroke subtypes was evaluated using an intention-to-treat principle. Statistical analysis was performed from March 12, 2013, to February 6, 2017. Interventions: Participants received rivaroxaban (2.5 mg twice a day) plus aspirin (100 mg once a day), rivaroxaban (5 mg twice a day), or aspirin (100 mg once a day). Main Outcomes and Measures: Risk of ischemic stroke subtypes during follow-up. Results: A total of 291 patients (66 women; mean [SD] age, 69.4 [8.5] years; 43 [14.8%] had a previous nonlacunar stroke) experienced an ischemic stroke. During the study, 49 patients (16.8%) received a diagnosis of atrial fibrillation. Applying TOAST criteria, 59 strokes (20.3%) were cardioembolic, 54 strokes (18.6%) were secondary to greater than 50% stenosis of the ipsilateral internal carotid artery, 42 strokes (14.4%) had a negative evaluation that met criteria for embolic stroke of undetermined source, and 21 strokes (7.2%) were secondary to small vessel disease. There were significantly fewer cardioembolic strokes (hazard ratio [HR], 0.40 [95% CI, 0.20-0.78]; P = .005) and embolic strokes of undetermined source (HR, 0.30 [95% CI, 0.12-0.74]; P = .006) in the combination therapy group compared with the aspirin-only group. A trend for reduction in strokes secondary to small vessel disease (HR, 0.36 [95% CI, 0.12-1.14]; P = .07) was not statistically significant. No significant difference was observed between the 2 groups in strokes secondary to greater than 50% carotid artery stenosis (HR, 0.85 [95% CI, 0.45-1.60]; P = .61). Rivaroxaban, 5 mg, twice daily showed a trend for reducing cardioembolic strokes compared with aspirin (HR, 0.57 [95% CI, 0.31-1.03]; P = .06) but was not associated with reducing other stroke subtypes. Conclusions and Relevance: For patients with systemic atherosclerosis, low-dose rivaroxaban plus aspirin was associated with large, significant reductions in cardioembolic strokes and embolic strokes of undetermined source. However, these results of exploratory analysis need to be independently confirmed before influencing clinical practice. Trial Registration: ClinicalTrials.gov identifier: NCT01776424.

5.
J Water Health ; 17(4): 622-632, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313999

RESUMO

Drinking water quality plays a remarkable role in human infections and diseases. This study used polymerase chain reaction (PCR) techniques to detect bacterial pathogens. In addition, a physicochemical analysis was performed on drinking water samples from several sources. A total of 123 drinking water samples were collected from different areas in the Jazan region in Saudi Arabia: ground water (40 samples), bottled water (15 samples), tap water (52 samples), and water purification shops (16 samples). To isolate the bacterial pathogens, the water samples were spread on Nutrient and MacConkey agar media, and the grown pathogens were then identified by the 16S ribosomal RNA technique. In 87 (70.7%) of the 123 drinking water samples, there was no pathogen growth on the two-culture medium. However, 36 (29.3%) of the samples were found to be contaminated with bacteria. The physicochemical analysis indicated that the water samples were within the Saudi drinking water standards. The bacteria were resistant to Cefotaxime, Cefotaxime/Clavulanic acid, Erythromycin, Penicillin G, Rifampin and Sulfamethoxazole-Trimethoprim, respectively. The findings suggest that in Jazan, bottled water is a safer source of potable water than tap water. The contamination in the water may be occurring at the reservoirs rather than the water sources.


Assuntos
Água Potável , Humanos , Arábia Saudita , Microbiologia da Água , Qualidade da Água , Recursos Hídricos
6.
Trials ; 20(1): 313, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31151483

RESUMO

BACKGROUND: Successful stroke trials require adequate recruitment. In this observational study, we assessed reasons for refusal to provide informed consent in eligible patients approached for clinical trial participation at the Vancouver Stroke Program. METHODS: We assessed screening logs from four trials that were actively recruiting at our center: three randomized trials, two of which investigated different antithrombotic strategies for secondary prevention (NAVIGATE-ESUS, NCT02313909 12/2014; DATAS-II, NCT02295826 11/2014) and one that investigated surgery plus medical management versus medical management alone for primary prevention (CREST-2, NCT02089217 03/2014). The fourth study was observational and non-randomized; all participants received an external monitoring device (PROPHECY, NCT03712865 10/2018). Screening logs from June 2015 to April 2017 were reviewed retrospectively. Subsequently, we used a prospective structured case report form for screening (May 2017-March 2018). We assessed and compared refusal rates between trials, demographics of those refusing consent, and their reasons for doing so. We used descriptive statistics, chi-square and Fisher's exact tests as appropriate for non-parametric data, and t-tests for parametric data. We examined likelihood of refusal by sex using multivariable logistic regression models including age and trial intervention as co-variables. RESULTS: A total of 235 patients (43% women) were approached for consent. More patients refused the surgical (59%) and antithrombotic trials (53%) compared with the non-randomized external monitoring device study (13%) (p < 0.001). Surgical trial refusals were primarily due to a desire for certainty in receiving a particular intervention (39%), with the majority of those patients wanting surgery. Refusals for the antithrombotic trials were mainly due to concerns with the potential side effects of the study drug (41%); refusals in the device trial were mainly due to disinterest (46%). Women refused participation more often than men (48% vs 33%). Women remained less likely to consent than men, even after adjustment for age and trial intervention (OR 0.46, 95% CI 0.26-0.82, p = 0.009). CONCLUSIONS: Concern surrounding drug safety, randomization, and disinterest were the chief deterrents to enrolment; there were also differences in rates of consent by gender. A better understanding of why patients refuse participation in stroke trials may help to develop future patient-directed communication strategies to improve enrolment. Further research is required to better understand the reasons underlying gender disparities in consent rates.

7.
J Stroke Cerebrovasc Dis ; 28(8): 2273-2279, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31160218

RESUMO

BACKGROUND: Embolic stroke of undetermined source (ESUS) identifies patients with cryptogenic ischemic stroke presumed due to embolism from several unidentified sources. Among patients with recent ESUS, we sought to determine independent predictors of recurrent ischemic stroke during treatment with aspirin or rivaroxaban and to assess the relative effects of these treatments according to risk. METHODS: Exploratory analyses of 7213 participants in the NAVIGATE ESUS international trial who were randomized to aspirin 100 mg/day or rivaroxaban 15 mg/day and followed for a median of 11 months, during which time there were 309 first recurrent ischemic strokes (4.6% per year). Baseline features were correlated with recurrent stroke by multivariate analysis. RESULTS: The 7 independent predictors of recurrent stroke were stroke or transient ischemic attack (TIA) prior to the qualifying stroke (hazard ratio [HR] 2.03 95% confidence internal [CI] 1.58-2.60), current tobacco user (HR 1.62, 95% CI 1.24-2.12), age (HR 1.02 per year increase, 95%CI 1.01-1.03), diabetes (HR 1.28, 95% CI 1.01-1.64), multiple acute infarcts on neuroimaging (HR 1.49, 95% CI 1.09-2.02), aspirin use prior to qualifying stroke (HR 1.34, 95% CI 1.02-1.70), and time from qualifying stroke to randomization (HR .98, 95% CI .97-.99). The rate of recurrent stroke rate was 2.6% per year for participants without any of these risk factors, and increased by an average of 45% for each independent predictor (P < .001). There were no significant interactions between treatment effects and independent stroke predictors or stroke risk status. CONCLUSIONS: In this large cohort of ESUS patients, several features including prior stroke or TIA, advanced age, current tobacco user, multiple acute infarcts on neuroimaging, and diabetes independently identified those with an increased risk of ischemic stroke recurrence. The relative effects of rivaroxaban and aspirin were similar across the spectrum of independent stroke predictors and recurrent stroke risk status.


Assuntos
Anticoagulantes/uso terapêutico , Aspirina/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Inibidores do Fator Xa/uso terapêutico , Embolia Intracraniana/tratamento farmacológico , Rivaroxabana/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Anticoagulantes/efeitos adversos , Aspirina/efeitos adversos , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/etiologia , Método Duplo-Cego , Inibidores do Fator Xa/efeitos adversos , Feminino , Humanos , Embolia Intracraniana/diagnóstico , Embolia Intracraniana/etiologia , Masculino , Pessoa de Meia-Idade , Recidiva , Medição de Risco , Fatores de Risco , Rivaroxabana/efeitos adversos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/etiologia , Fatores de Tempo , Resultado do Tratamento
9.
J Nerv Ment Dis ; 207(2): 100-105, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30672872

RESUMO

Cognitive deficits have been demonstrated in people in the euthymic phase of bipolar disorder. This cross-sectional study compared euthymic bipolar disorder patients (n = 30) with never psychiatrically ill controls (n = 30) on a neuropsychological test battery containing tasks of executive function, the Wisconsin Card Sorting Test (WCST), attention and working memory, digits forward and backward, and speed of information processing digit symbol. Scores on the Mini-Mental State Examination (MMSE) and vocabulary test did not differ between the groups. The bipolar group was significantly impaired compared with controls on various indices of executive function on the WCST and on the digit tests. The impaired performance on the digit tests, but not the WCST, was significantly associated with medication status, notably prescribed benzodiazepines. There was no significant effect of severity or course of illness on performance. The findings support the hypothesis that impairments in executive function are present between illness episodes in bipolar disorder, and so they are not simply state markers.


Assuntos
Transtorno Bipolar/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Função Executiva/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Transtorno Bipolar/complicações , Disfunção Cognitiva/etiologia , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Adulto Jovem
10.
Circulation ; 139(9): 1134-1145, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30667279

RESUMO

BACKGROUND: Strokes were significantly reduced by the combination of rivaroxaban plus aspirin in comparison with aspirin in the COMPASS trial (Cardiovascular Outcomes for People Using Anticoagulation Strategies). We present detailed analyses of stroke by type, predictors, and antithrombotic effects in key subgroups. METHODS: Participants had stable coronary artery or peripheral artery disease and were randomly assigned to receive aspirin 100 mg once daily (n=9126), rivaroxaban 5 mg twice daily (n=9117), or rivaroxaban 2.5 mg twice daily plus aspirin (n=9152). Patients who required anticoagulation or had a stroke within 1 month, previous lacunar stroke, or intracerebral hemorrhage were excluded. RESULTS: During a mean follow-up of 23 months, fewer patients had strokes in the rivaroxaban plus aspirin group than in the aspirin group (83 [0.9% per year] versus 142 [1.6% per year]; hazard ratio [HR], 0.58; 95% CI, 0.44-0.76; P<0.0001). Ischemic/uncertain strokes were reduced by nearly half (68 [0.7% per year] versus 132 [1.4% per year]; HR, 0.51; 95% CI, 0.38-0.68; P<0.0001) by the combination in comparison with aspirin. No significant difference was noted in the occurrence of stroke in the rivaroxaban alone group in comparison with aspirin: annualized rate of 0.7% (HR, 0.82; 95% CI, 0.65-1.05). The occurrence of fatal and disabling stroke (modified Rankin Scale, 3-6) was decreased by the combination (32 [0.3% per year] versus 55 [0.6% per year]; HR, 0.58; 95% CI, 0.37-0.89; P=0.01). Independent predictors of stroke were prior stroke, hypertension, systolic blood pressure at baseline, age, diabetes mellitus, and Asian ethnicity. Prior stroke was the strongest predictor of incident stroke (HR, 3.63; 95% CI, 2.65-4.97; P<0.0001) and was associated with a 3.4% per year rate of stroke recurrence on aspirin. The effect of the combination in comparison with aspirin was consistent across subgroups with high stroke risk, including those with prior stroke. CONCLUSIONS: Low-dose rivaroxaban plus aspirin is an important new antithrombotic option for primary and secondary stroke prevention in patients with clinical atherosclerosis. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01776424.


Assuntos
Aspirina/administração & dosagem , Doença da Artéria Coronariana , Doença Arterial Periférica , Rivaroxabana/administração & dosagem , Acidente Vascular Cerebral , Idoso , Idoso de 80 Anos ou mais , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/epidemiologia , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/tratamento farmacológico , Doença Arterial Periférica/epidemiologia , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle
11.
Biochem Biophys Res Commun ; 509(3): 779-783, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30616886

RESUMO

Repair of DNA alkylation damage is essential for maintaining genome integrity and Fe(II)/2-oxoglutarate(2OG)-dependent dioxygenase family of enzymes play crucial role in repairing some of the alkylation damages. Alkylation repair protein-B (AlkB) of Escherichia coli belongs to Fe(II)/2OG-dependent dioxygenase family and carries out DNA dealkylation repair. We report here identification of a hypothetical Mycobacterium leprae protein (accession no. ML0190) from the genomic database and show that this 615-bp open reading frame encodes a protein with sequence and structural similarity to Fe(II)/2OG-dependent dioxygenase AlkB. We identified mRNA transcript of this gene in the M. leprae infected clinical skin biopsy samples isolated from the leprosy patients. Heterologous expression of ML0190 in methyl methane sulfonate (MMS) sensitive and DNA repair deficient strain of Saccharomyces cerevisiae and Escherichia coli resulted in resistance to alkylating agent MM. The results of the present study imply that Mycobacterium leprae ML0190 is involved in protecting the bacterial genome from DNA alkylation damage.


Assuntos
Proteínas de Bactérias/genética , Escherichia coli/efeitos dos fármacos , Metanossulfonato de Metila/toxicidade , Mutagênicos/toxicidade , Mycobacterium leprae/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Alquilação/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Escherichia coli/genética , Genes Bacterianos , Genoma Bacteriano/efeitos dos fármacos , Humanos , Hanseníase/microbiologia , Modelos Moleculares , Mycobacterium leprae/efeitos dos fármacos , Saccharomyces cerevisiae/genética
12.
Lancet Neurol ; 17(12): 1053-1060, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30274772

RESUMO

BACKGROUND: Patent foramen ovale (PFO) is a contributor to embolic stroke of undetermined source (ESUS). Subgroup analyses from previous studies suggest that anticoagulation could reduce recurrent stroke compared with antiplatelet therapy. We hypothesised that anticoagulant treatment with rivaroxaban, an oral factor Xa inhibitor, would reduce the risk of recurrent ischaemic stroke compared with aspirin among patients with PFO enrolled in the NAVIGATE ESUS trial. METHODS: NAVIGATE ESUS was a double-blinded, randomised, phase 3 trial done at 459 centres in 31 countries that assessed the efficacy and safety of rivaroxaban versus aspirin for secondary stroke prevention in patients with ESUS. For this prespecified subgroup analysis, cohorts with and without PFO were defined on the basis of transthoracic echocardiography (TTE) and transoesophageal echocardiography (TOE). The primary efficacy outcome was time to recurrent ischaemic stroke between treatment groups. The primary safety outcome was major bleeding, according to the criteria of the International Society of Thrombosis and Haemostasis. The primary analyses were based on the intention-to-treat population. Additionally, we did a systematic review and random-effects meta-analysis of studies in which patients with cryptogenic stroke and PFO were randomly assigned to receive anticoagulant or antiplatelet therapy. FINDINGS: Between Dec 23, 2014, and Sept 20, 2017, 7213 participants were enrolled and assigned to receive rivaroxaban (n=3609) or aspirin (n=3604). Patients were followed up for a mean of 11 months because of early trial termination. PFO was reported as present in 534 (7·4%) patients on the basis of either TTE or TOE. Patients with PFO assigned to receive aspirin had a recurrent ischaemic stroke rate of 4·8 events per 100 person-years compared with 2·6 events per 100 person-years in those treated with rivaroxaban. Among patients with known PFO, there was insufficient evidence to support a difference in risk of recurrent ischaemic stroke between rivaroxaban and aspirin (hazard ratio [HR] 0·54; 95% CI 0·22-1·36), and the risk was similar for those without known PFO (1·06; 0·84-1·33; pinteraction=0·18). The risks of major bleeding with rivaroxaban versus aspirin were similar in patients with PFO detected (HR 2·05; 95% CI 0·51-8·18) and in those without PFO detected (HR 2·82; 95% CI 1·69-4·70; pinteraction=0·68). The random-effects meta-analysis combined data from NAVIGATE ESUS with data from two previous trials (PICSS and CLOSE) and yielded a summary odds ratio of 0·48 (95% CI 0·24-0·96; p=0·04) for ischaemic stroke in favour of anticoagulation, without evidence of heterogeneity. INTERPRETATION: Among patients with ESUS who have PFO, anticoagulation might reduce the risk of recurrent stroke by about half, although substantial imprecision remains. Dedicated trials of anticoagulation versus antiplatelet therapy or PFO closure, or both, are warranted. FUNDING: Bayer and Janssen.

13.
Microb Pathog ; 124: 316-321, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30172902

RESUMO

Mycobacterium leprae is an unculturable obligate pathogen and causative agent for debilitating human disease leprosy. Due to reductive genome evolution M leprae genome harbours large number of pseudogenes and small number of genes (∼1600 genes and ∼1300 pseudogenes). How M leprae remained a successful human parasite with small set of genes remains poorly understood and provided us the impetus to investigate the intergenic regions of M leprae genome for the presence of possible open reading frames (ORFs). In this work, we have manually scanned all the intergenic regions of M leprae genome and identified 106 potential ORFs. Among these, 12 are large ORFs: encoding hypothetical proteins (HP) of more than 100 amino acids. We have also found 67 ORFs encoding 50-100 amino acids proteins and another 27 ORFs for 30-50 amino acids peptides. We have validated the presence of transcripts for large HPs by quantitative reverse transcriptase PCR (qRT-PCR). Our results suggest that some of the M leprae large HPs are indeed expressed at low level in leprosy patients. The present results will shed light on the intergenic ORFs of M leprae and further our understanding of the pathogenesis of leprosy.

14.
Int J Stroke ; 13(7): 743-758, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30021491

RESUMO

The Canadian Stroke Best Practice Consensus Statement Acute Stroke Management during Pregnancy is the second of a two-part series devoted to stroke in pregnancy. The first part focused on the unique aspects of secondary stroke prevention in a woman with a prior history of stroke who is, or is planning to become, pregnant. This document focuses on the management of a woman who experiences an acute stroke during pregnancy. This consensus statement was developed in recognition of the need for a specifically tailored approach to the management of this group of patients in the absence of any broad-based, stroke-specific guidelines or consensus statements, which do not exist currently. The foundation for the development of this document was the concept that maternal health is vital for fetal well-being; therefore, management decisions should be based first on the confluence of two clinical considerations: (a) decisions that would be made if the patient wasn't pregnant and (b) decisions that would be made if the patient hadn't had a stroke, then nuanced as needed. While empirical research in this area is limited, this consensus document is based on the best available literature and guided by expert consensus. Issues addressed in this document include initial emergency management, diagnostic imaging, acute stroke treatment, the management of hemorrhagic stroke, anesthetic management, post stroke management for women with a stroke in pregnancy, intrapartum considerations, and postpartum management. These statements are appropriate for healthcare professionals across all disciplines and system planners to ensure pregnant women who experience a stroke have timely access to both expert neurological and obstetric care.

15.
BMJ Open ; 8(7): e021521, 2018 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-29982215

RESUMO

OBJECTIVES: Covert stroke after non-cardiac surgery may have substantial impact on duration and quality of life. In non-surgical patients, covert stroke is more common than overt stroke and is associated with an increased risk of cognitive decline and dementia. Little is known about covert stroke after non-cardiac surgery.NeuroVISION is a multicentre, international, prospective cohort study that will characterise the association between perioperative acute covert stroke and postoperative cognitive function. SETTING AND PARTICIPANTS: We are recruiting study participants from 12 tertiary care hospitals in 10 countries on 5 continents. PARTICIPANTS: We are enrolling patients ≥65 years of age, requiring hospital admission after non-cardiac surgery, who have an anticipated length of hospital stay of at least 2 days after elective non-cardiac surgery that occurs under general or neuraxial anaesthesia. PRIMARY AND SECONDARY OUTCOME MEASURES: Patients are recruited before elective non-cardiac surgery, and their cognitive function is measured using the Montreal Cognitive Assessment (MoCA) instrument. After surgery, a brain MRI study is performed between postoperative days 2 and 9 to determine the presence of acute brain infarction. One year after surgery, the MoCA is used to assess postoperative cognitive function. Physicians and patients are blinded to the MRI study results until after the last patient follow-up visit to reduce outcome ascertainment bias.We will undertake a multivariable logistic regression analysis in which the dependent variable is the change in cognitive function 1 year after surgery, and the independent variables are acute perioperative covert stroke as well as other clinical variables that are associated with cognitive dysfunction. CONCLUSIONS: The NeuroVISION study will characterise the epidemiology of covert stroke and its clinical consequences. This will be the largest and the most comprehensive study of perioperative stroke after non-cardiac surgery. TRIAL REGISTRATION NUMBER: NCT01980511; Pre-results.

16.
Int J Stroke ; : 1747493018784478, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30058959

RESUMO

Background Covert vascular disease of the brain manifests as infarcts, white matter hyperintensities, and microbleeds on MRI. Their cumulative effect is often a decline in cognition, motor impairment, and psychiatric disorders. Preventive therapies for covert brain ischemia have not been established but represent a huge unmet clinical need. Aims The MRI substudy examines the effects of the antithrombotic regimens in COMPASS on incident covert brain infarcts (the primary outcome), white matter hyperintensities, and cognitive and functional status in a sample of consenting COMPASS participants without contraindications to MRI. Methods COMPASS is a randomized superiority trial testing rivaroxaban 2.5 mg bid plus acetylsalicylic acid 100 mg and rivaroxaban 5 mg bid against acetylsalicylic acid 100 mg per day for the combined endpoint of MI, stroke, and cardiovascular death in individuals with stable coronary artery disease or peripheral artery disease. T1-weighted, T2-weighted, T2*-weighted, and FLAIR images were obtained close to randomization and near the termination of assigned antithrombotic therapy; biomarker and genetic samples at randomization and one month, and cognitive and functional assessment at randomization, after two years and at the end of study. Results Between March 2013 and May 2016, 1905 participants were recruited from 86 centers in 16 countries. Of these participants, 1760 underwent baseline MRI scans that were deemed technically adequate for interpretation. The mean age at entry of participants with interpretable MRI was 71 years and 23.5% were women. Coronary artery disease was present in 90.4% and 28.1% had peripheral artery disease. Brain infarcts were present in 34.8%, 29.3% had cerebral microbleeds, and 93.0% had white matter hyperintensities. The median Montreal Cognitive Assessment score was 26 (interquartile range 23-28). Conclusions The COMPASS MRI substudy will examine the effect of the antithrombotic interventions on MRI-determined covert brain infarcts and cognition. Demonstration of a therapeutic effect of the antithrombotic regimens on brain infarcts would have implications for prevention of cognitive decline and provide insight into the pathogenesis of vascular cognitive decline.

17.
Lancet ; 391(10137): 2325-2334, 2018 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-29900874

RESUMO

BACKGROUND: Myocardial injury after non-cardiac surgery (MINS) increases the risk of cardiovascular events and deaths, which anticoagulation therapy could prevent. Dabigatran prevents perioperative venous thromboembolism, but whether this drug can prevent a broader range of vascular complications in patients with MINS is unknown. The MANAGE trial assessed the potential of dabigatran to prevent major vascular complications among such patients. METHODS: In this international, randomised, placebo-controlled trial, we recruited patients from 84 hospitals in 19 countries. Eligible patients were aged at least 45 years, had undergone non-cardiac surgery, and were within 35 days of MINS. Patients were randomly assigned (1:1) to receive dabigatran 110 mg orally twice daily or matched placebo for a maximum of 2 years or until termination of the trial and, using a partial 2-by-2 factorial design, patients not taking a proton-pump inhibitor were also randomly assigned (1:1) to omeprazole 20 mg once daily, for which results will be reported elsewhere, or matched placebo to measure its effect on major upper gastrointestinal complications. Research personnel randomised patients through a central 24 h computerised randomisation system using block randomisation, stratified by centre. Patients, health-care providers, data collectors, and outcome adjudicators were masked to treatment allocation. The primary efficacy outcome was the occurrence of a major vascular complication, a composite of vascular mortality and non-fatal myocardial infarction, non-haemorrhagic stroke, peripheral arterial thrombosis, amputation, and symptomatic venous thromboembolism. The primary safety outcome was a composite of life-threatening, major, and critical organ bleeding. Analyses were done according to the intention-to-treat principle. This trial is registered with ClinicalTrials.gov, number NCT01661101. FINDINGS: Between Jan 10, 2013, and July 17, 2017, we randomly assigned 1754 patients to receive dabigatran (n=877) or placebo (n=877); 556 patients were also randomised in the omeprazole partial factorial component. Study drug was permanently discontinued in 401 (46%) of 877 patients allocated to dabigatran and 380 (43%) of 877 patients allocated to placebo. The composite primary efficacy outcome occurred in fewer patients randomised to dabigatran than placebo (97 [11%] of 877 patients assigned to dabigatran vs 133 [15%] of 877 patients assigned to placebo; hazard ratio [HR] 0·72, 95% CI 0·55-0·93; p=0·0115). The primary safety composite outcome occurred in 29 patients (3%) randomised to dabigatran and 31 patients (4%) randomised to placebo (HR 0·92, 95% CI 0·55-1·53; p=0·76). INTERPRETATION: Among patients who had MINS, dabigatran 110 mg twice daily lowered the risk of major vascular complications, with no significant increase in major bleeding. Patients with MINS have a poor prognosis; dabigatran 110 mg twice daily has the potential to help many of the 8 million adults globally who have MINS to reduce their risk of a major vascular complication [corrected]. FUNDING: Boehringer Ingelheim and Canadian Institutes of Health Research.


Assuntos
Dabigatrana/farmacologia , Hemorragia/complicações , Infarto do Miocárdio/tratamento farmacológico , Doença Arterial Periférica/complicações , Acidente Vascular Cerebral/complicações , Tromboembolia Venosa/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antitrombinas/farmacologia , Dabigatrana/administração & dosagem , Dabigatrana/efeitos adversos , Feminino , Hemorragia/tratamento farmacológico , Hemorragia/prevenção & controle , Humanos , Masculino , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/mortalidade , Omeprazol/administração & dosagem , Omeprazol/uso terapêutico , Período Perioperatório/mortalidade , Doença Arterial Periférica/tratamento farmacológico , Doença Arterial Periférica/prevenção & controle , Efeito Placebo , Inibidores da Bomba de Prótons/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle , Trombose/patologia , Resultado do Tratamento , Troponina/efeitos dos fármacos , Troponina/metabolismo , Tromboembolia Venosa/prevenção & controle
18.
Am Heart J ; 201: 160-163, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29764671

RESUMO

BACKGROUND: The Asymptomatic Atrial Fibrillation and Stroke Evaluation in Pacemaker Patients and the Atrial Fibrillation Reduction Atrial Pacing Trial (ASSERT) demonstrated that subclinical atrial fibrillation (SCAF) was associated with a 2.5-fold increased risk of stroke. However, the absolute stroke rate was only 1.7% per year and fewer than 20% patients with stroke had SCAF in the preceding 30 days. This raises the possibility that SCAF is merely a risk marker for stroke rather than the cause. Systematic characterization of stroke subtypes among patients with SCAF would help clarify this issue. METHODS: All ischemic strokes that occurred in the ASSERT trial were blindly adjudicated by stroke neurologists, classified as cortical versus subcortical, and subtyped using modified TOAST criteria. Stroke severity was measured using the modified Rankin Score. RESULTS: Of the 44 participants who had an ischemic stroke, 14 had SCAF before stroke. Among patients with SCAF who had stroke, 57% of strokes (n = 8) were judged to be cardioembolic, 36% to be lacunar (n = 5), and 7% (n = 1) to be large artery disease. However, of 5 patients who had SCAF detected within 30 days before their index stroke, 4 patients had a cardioembolic stroke. The average duration of SCAF in these 4 patients was 6.0 ± 6.1 h/d. The modified Rankin score at 30 days was similar between patients with (2.7 ± 2.3) and without SCAF (2.3 ± 2.0; P = .68). CONCLUSIONS: In patients with SCAF and stroke, SCAF seems probably causal in many cases; however, in more than 40%, it seems to be acting only as a risk marker.

19.
N Engl J Med ; 378(23): 2191-2201, 2018 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-29766772

RESUMO

BACKGROUND: Embolic strokes of undetermined source represent 20% of ischemic strokes and are associated with a high rate of recurrence. Anticoagulant treatment with rivaroxaban, an oral factor Xa inhibitor, may result in a lower risk of recurrent stroke than aspirin. METHODS: We compared the efficacy and safety of rivaroxaban (at a daily dose of 15 mg) with aspirin (at a daily dose of 100 mg) for the prevention of recurrent stroke in patients with recent ischemic stroke that was presumed to be from cerebral embolism but without arterial stenosis, lacune, or an identified cardioembolic source. The primary efficacy outcome was the first recurrence of ischemic or hemorrhagic stroke or systemic embolism in a time-to-event analysis; the primary safety outcome was the rate of major bleeding. RESULTS: A total of 7213 participants were enrolled at 459 sites; 3609 patients were randomly assigned to receive rivaroxaban and 3604 to receive aspirin. Patients had been followed for a median of 11 months when the trial was terminated early because of a lack of benefit with regard to stroke risk and because of bleeding associated with rivaroxaban. The primary efficacy outcome occurred in 172 patients in the rivaroxaban group (annualized rate, 5.1%) and in 160 in the aspirin group (annualized rate, 4.8%) (hazard ratio, 1.07; 95% confidence interval [CI], 0.87 to 1.33; P=0.52). Recurrent ischemic stroke occurred in 158 patients in the rivaroxaban group (annualized rate, 4.7%) and in 156 in the aspirin group (annualized rate, 4.7%). Major bleeding occurred in 62 patients in the rivaroxaban group (annualized rate, 1.8%) and in 23 in the aspirin group (annualized rate, 0.7%) (hazard ratio, 2.72; 95% CI, 1.68 to 4.39; P<0.001). CONCLUSIONS: Rivaroxaban was not superior to aspirin with regard to the prevention of recurrent stroke after an initial embolic stroke of undetermined source and was associated with a higher risk of bleeding. (Funded by Bayer and Janssen Research and Development; NAVIGATE ESUS ClinicalTrials.gov number, NCT02313909 .).


Assuntos
Aspirina/uso terapêutico , Inibidores do Fator Xa/uso terapêutico , Embolia Intracraniana/tratamento farmacológico , Inibidores da Agregação de Plaquetas/uso terapêutico , Rivaroxabana/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Idoso , Aspirina/efeitos adversos , Isquemia Encefálica/prevenção & controle , Inibidores do Fator Xa/efeitos adversos , Feminino , Hemorragia/induzido quimicamente , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação de Plaquetas/efeitos adversos , Rivaroxabana/efeitos adversos , Prevenção Secundária/métodos , Acidente Vascular Cerebral/etiologia
20.
Anal Chem ; 90(9): 5781-5787, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29627976

RESUMO

Here we use two chemical separation procedures to determine exceptionally low Os concentrations (∼10-15 g g-1) and Os isotopic composition in polar snow/ice. Approximately 50 g of meltwater is spiked with 190Os tracer solution and frozen at -20 °C in quartz-glass ampules. A mixture of H2O2 and HNO3 is then added, and the sample is heated to 300 °C at 100 bar. This allows tracer Os to be equilibrated with the sample as all Os species are oxidized to OsO4. The resulting OsO4 is separated using either distillation (Method-I) or solvent-extraction (Method-II), purified, and measured using negative thermal ionization mass spectrometry (N-TIMS). A new technique is presented that minimizes Re and Os blanks of the Pt filaments used in N-TIMS. We analyze snow collected from Summit, Greenland during 2009, 2014, and 2017. We find that the average Os concentration of the snow is 0.459 ± 0.018 (95% C.I.) fg g-1 corresponding to an Os flux of 0.0579 ± 0.0023 (95% C.I.) fmol cm-2 yr-1. The average R(187Os/188Os) ratio of the Summit snow is 0.264 ± 0.026 (95% C.I.). Assuming that the volcanic source is negligible, the average ratio indicates that about 0.0518 ± 0.0040 (95% C.I.) fmol cm-2 yr-1 of Os is of cosmic derivation, corresponding to an accretion rate of extra-terrestrial Os to the Earth of 264 ± 21 mol yr-1.

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