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Multidrug resistant organisms are a serious threat to human health1,2. Fast, accurate antibiotic susceptibility testing (AST) is a critical need in addressing escalating antibiotic resistance, since delays in identifying multidrug resistant organisms increase mortality3,4 and use of broad-spectrum antibiotics, further selecting for resistant organisms. Yet current growth-based AST assays, such as broth microdilution5, require several days before informing key clinical decisions. Rapid AST would transform the care of patients with infection while ensuring that our antibiotic arsenal is deployed as efficiently as possible. Growth-based assays are fundamentally constrained in speed by doubling time of the pathogen, and genotypic assays are limited by the ever-growing diversity and complexity of bacterial antibiotic resistance mechanisms. Here we describe a rapid assay for combined genotypic and phenotypic AST through RNA detection, GoPhAST-R, that classifies strains with 94–99% accuracy by coupling machine learning analysis of early antibiotic-induced transcriptional changes with simultaneous detection of key genetic resistance determinants to increase accuracy of resistance detection, facilitate molecular epidemiology and enable early detection of emerging resistance mechanisms. This two-pronged approach provides phenotypic AST 24–36 h faster than standard workflows, with

Background and Purpose— Both low serum calcium and magnesium levels have been associated with the extent of bleeding in patients with intracerebral hemorrhage, suggesting hypocalcemia- and hypomagnesemia-induced coagulopathy as a possible underlying mechanism. We hypothesized that serum albumin-corrected total calcium and magnesium levels are associated with ruptured intracranial aneurysms. Methods— The medical records of 4701 patients, including 1201 prospective patients, diagnosed at the Brigham and Women’s Hospital and Massachusetts General Hospital between 1990 and 2016 were reviewed and analyzed. One thousand two hundred seventy-five patients had available serum calcium, magnesium, and albumin values within 1 day of diagnosis. Individuals were divided into cases with ruptured aneurysms and controls with unruptured aneurysms. Univariable and multivariable logistic regression analyses were performed to determine the association between serum albumin-corrected total calcium and magnesium levels and ruptured aneurysms. Results— In multivariable analysis, both albumin-corrected calcium (odds ratio, 0.33; 95% confidence interval, 0.27–0.40) and magnesium (odds ratio, 0.40; 95% confidence interval, 0.28–0.55) were significantly and inversely associated with ruptured intracranial aneurysms. Conclusions— In this large case–control study, hypocalcemia and hypomagnesemia at diagnosis were significantly associated with ruptured aneurysms. Impaired hemostasis caused by hypocalcemia and hypomagnesemia may explain this association.

ObjectiveTo determine the association between ruptured saccular aneurysms and aspirin use/aspirin dose.MethodsFour thousand seven hundred one patients who were diagnosed at the Massachusetts General Hospital and Brigham and Women's Hospital between 1990 and 2016 with 6,411 unruptured and ruptured saccular intracranial aneurysms were evaluated. Univariable and multivariable logistic regression analyses were performed to determine the association between aneurysmal subarachnoid hemorrhage and aspirin use, including aspirin dose. Inverse probability weighting using propensity scores was used to adjust for potential differences in baseline characteristics between cases and controls. Additional analyses were performed to examine the association of aspirin use and rerupture before treatment.ResultsIn multivariate analysis with propensity score weighting, aspirin use (odds ratio [OR] 0.60, 95% confidence interval [CI] 0.45–0.80) was significantly associated with decreased risk of ruptured intracranial aneurysms. There was a significant inverse dose-response relationship between aspirin dose and aneurysmal subarachnoid hemorrhage (OR 0.65, 95% CI 0.53–0.81). In contrast, there was a significant association between aspirin use and increased risk of rerupture before treatment (OR 8.15, 95% CI 2.22–30.0).ConclusionsIn this large case-control study, aspirin therapy at diagnosis was associated with a significantly decreased risk of subarachnoid hemorrhage, with an inverse dose-response relationship among aspirin users. However, once rupture has occurred, aspirin is associated with an increased risk of rerupture before treatment.

Following ischemic stroke, the penumbra, at-risk neural tissue surrounding the core infarct, survives for a variable period of time before progressing to infarction. We investigated genetic determinants of the size of penumbra in mice subjected to middle cerebral artery occlusion (MCAO) using a genome-wide approach. 449 male mice from 33 inbred strains underwent MCAO for 6 hours (215 mice) or 24 hours (234 mice). A genome-wide association study using genetic data from the Mouse HapMap project was performed to examine the effects of genetic variants on the penumbra ratio, defined as the ratio of the infarct volume after 6 hours to the infarct volume after 24 hours of MCAO. Efficient mixed model analysis was used to account for strain interrelatedness. Penumbra ratio differed significantly by strain (F = 2.7, P Clint1, Nbea, Smtnl2, Rin3, Dclk1, and Slc24a4.

OBJECTIVEAlthough cigarette smoking is one of the strongest risk factors for cerebral aneurysm development and rupture, there are limited data evaluating the impact of smoking on outcomes after aneurysmal subarachnoid hemorrhage (SAH). Additionally, two recent studies suggested that nicotine replacement therapy was associated with improved neurological outcomes among smokers who had sustained an SAH compared with smokers who did not receive nicotine.METHODSPatients who underwent endovascular or microsurgical repair of a ruptured cerebral aneurysm were extracted from the Nationwide Inpatient Sample (NIS, 2009–2011) and stratified by cigarette smoking. Multivariable logistic regression analyzed in-hospital mortality, complications, tracheostomy or gastrostomy placement, and discharge to institutional care (a nursing or an extended care facility). Additionally, the composite NIS-SAH outcome measure (based on mortality, tracheostomy or gastrostomy, and discharge disposition) was evaluated, which has been shown to have excellent agreement with a modified Rankin Scale score greater than 3. Covariates included in regression constructs were patient age, sex, race/ethnicity, insurance status, socioeconomic status, comorbidities (including hypertension, drug and alcohol abuse), the NIS-SAH severity scale (previously validated against the Hunt and Hess grade), treatment modality used for aneurysm repair, and hospital characteristics. A sensitivity analysis was performed matching smokers to nonsmokers on age, sex, number of comorbidities, and NIS-SAH severity scale score.RESULTSAmong the 5784 admissions evaluated, 37.1% (n = 2148) had a diagnosis of tobacco use, of which 31.1% (n = 1800) were current and 6.0% (n = 348) prior tobacco users. Smokers were significantly younger (mean age 51.4 vs 56.2 years) and had more comorbidities compared with nonsmokers (p < 0.001). There were no significant differences in mortality, total complications, or neurological complications by smoking status. However, compared with nonsmokers, smokers had significantly decreased adjusted odds of tracheostomy or gastrostomy placement (11.9% vs 22.7%, odds ratio [OR] 0.63, 95% confidence interval [CI] 0.51–0.78, p < 0.001), discharge to institutional care (OR 0.71, 95% CI 0.57–0.89, p = 0.002), and a poor outcome (OR 0.65, 95% CI 0.55–0.77, p < 0.001). Similar statistical associations were noted in the matched-pairs sensitivity analysis and in a subgroup of poor-grade patients (the upper quartile of the NIS-SAH severity scale).CONCLUSIONSIn this nationwide study, smokers experienced SAH at a younger age and had a greater number of comorbidities compared with nonsmokers, highlighting the negative ramifications of cigarette smoking among patients with cerebral aneurysms. However, smoking was also associated with paradoxical superior outcomes on some measures, and future research to confirm and further understand the basis of this relationship is needed.

Although RNA-seq is a powerful tool, the considerable time and cost associated with library construction has limited its utilization for various applications. RNAtag-Seq, an approach to generate multiple RNA-seq libraries in a single reaction, lowers time and cost per sample, and it produces data on prokaryotic and eukaryotic samples that are comparable to those generated by traditional strand-specific RNA-seq approaches.