Circumstances and consequences of falls among people with chronic stroke

Falls are common after stroke; however, circumstances and consequences are relatively unknown. Our objectives were to identify the differences between fallers and non-fallers among people with chronic stroke, identify the circumstances of fall events, and examine the consequences of the falls. This is a secondary data analysis; all participants included sustained a stroke. Variables included demographics, stroke characteristics, and comorbidities. Falls were collected via self-report, and circumstances and consequences were derived from participant description of the event and categorized as appropriate. Among 160 participants, 53 (33%) reported a fall during the 1 yr period. Circumstances of falls were categorized as intrinsic or extrinsic. Location and circumstance of the fall were included: 70% occurred at home and 40% were associated with impaired physical or mental state (e.g., inattention to tying shoes). Additionally, 21% of falls were associated with activities of daily living and mobility and 34% with slips or trips. The majority who fell sustained an injury (72%). Injuries ranged from bruising to fractures, and 55% of those with an injury sought medical care (32% to emergency department). Poststroke falls are associated with an alarming rate of injury and healthcare utilization. Targeting mental and physical states may be key to fall prevention

Diagnosing and managing sleep apnea in patients with chronic cerebrovascular disease: a randomized trial of a home-based strategy

Background Obstructive sleep apnea is common and associated with poor outcomes after stroke or transient ischemic attack (TIA). We sought to determine whether the intervention strategy improved sleep apnea detection, obstructive sleep apnea (OSA) treatment, and hypertension control among patients with chronic cerebrovascular disease and hypertension. Methods In this randomized controlled strategy trial intervention, patients received unattended polysomnography at baseline, and patients with OSA (apnea-hypopnea index ≥5 events/h) received auto-titrating continuous positive airway pressure (CPAP) for up to 1 year. Control patients received usual care and unattended polysomnography at the end of the study, to identify undiagnosed OSA. Both groups received 24-h blood pressure assessments at baseline and end of the study. “Excellent” CPAP adherence was defined as cumulative use of ≥4 h/night for ≥70% of the nights. Results Among 225 randomized patients (115 control; 110 intervention), 61.9% (120/194) had sleep apnea. The strategy successfully diagnosed sleep apnea with 97.1% (102/105) valid studies; 90.6% (48/53, 95% CI 82.7–98.4%) of sleep apnea was undiagnosed among control patients. The intervention improved long-term excellent CPAP use: 38.6% (22/57) intervention versus 0% (0/2) control (p < 0.0001). The intervention did not improve hypertension control in this population with well-controlled baseline blood pressure: intervention, 132.7 mmHg (±standard deviation, 14.1) versus control, 133.8 mmHg (±14.0) (adjusted difference, −1.1 mmHg, 95% CI (−4.2, 2.0)), p = 0.48). Conclusions Patients with cerebrovascular disease and hypertension have a high prevalence of OSA. The use of portable polysomnography, and auto-titrating CPAP in the patients’ homes, improved both the diagnosis and the treatment for sleep apnea compared with usual care but did not lower blood pressure

Signal Processing Research Program

Contains table of contents for Part III, table of contents for Section 1, an introduction and reports on fourteen research projects.Charles S. Draper Laboratory Contract DL-H-404158U.S. Navy - Office of Naval Research Grant N00014-89-J-1489National Science Foundation Grant MIP 87-14969Battelle LaboratoriesTel-Aviv University, Department of Electronic SystemsU.S. Army Research Office Contract DAAL03-86-D-0001The Federative Republic of Brazil ScholarshipSanders Associates, Inc.Bell Northern Research, Ltd.Amoco Foundation FellowshipGeneral Electric FellowshipNational Science Foundation FellowshipU.S. Air Force - Office of Scientific Research FellowshipU.S. Navy - Office of Naval Research Grant N00014-85-K-0272Natural Science and Engineering Research Council of Canada - Science and Technology Scholarshi

c-di-GMP Turn-Over in Clostridium difficile Is Controlled by a Plethora of Diguanylate Cyclases and Phosphodiesterases

Clostridium difficile infections have become a major healthcare concern in the last decade during which the emergence of new strains has underscored this bacterium's capacity to cause persistent epidemics. c-di-GMP is a bacterial second messenger regulating diverse bacterial phenotypes, notably motility and biofilm formation, in proteobacteria such as Vibrio cholerae, Pseudomonas aeruginosa, and Salmonella. c-di-GMP is synthesized by diguanylate cyclases (DGCs) that contain a conserved GGDEF domain. It is degraded by phosphodiesterases (PDEs) that contain either an EAL or an HD-GYP conserved domain. Very little is known about the role of c-di-GMP in the regulation of phenotypes of Gram-positive or fastidious bacteria. Herein, we exposed the main components of c-di-GMP signalling in 20 genomes of C. difficile, revealed their prevalence, and predicted their enzymatic activity. Ectopic expression of 31 of these conserved genes was carried out in V. cholerae to evaluate their effect on motility and biofilm formation, two well-characterized phenotype alterations associated with intracellular c-di-GMP variation in this bacterium. Most of the predicted DGCs and PDEs were found to be active in the V. cholerae model. Expression of truncated versions of CD0522, a protein with two GGDEF domains and one EAL domain, suggests that it can act alternatively as a DGC or a PDE. The activity of one purified DGC (CD1420) and one purified PDE (CD0757) was confirmed by in vitro enzymatic assays. GTP was shown to be important for the PDE activity of CD0757. Our results indicate that, in contrast to most Gram-positive bacteria including its closest relatives, C. difficile encodes a large assortment of functional DGCs and PDEs, revealing that c-di-GMP signalling is an important and well-conserved signal transduction system in this human pathogen

Delineation of the integrase-attachment and origin-of-transfer regions of the symbiosis island ICEMlSymR7A.

Integrative and conjugative elements (ICEs) are chromosomally-integrated mobile genetic elements that excise from their host chromosome and transfer to other bacteria via conjugation. ICEMlSymR7A is the prototypical member of a large family of "symbiosis ICEs" which confer upon their hosts the ability to form a nitrogen-fixing symbiosis with a variety of legume species. Mesorhizobial symbiosis ICEs carry a common core of mobilisation genes required for integration, excision and conjugative transfer. IntS of ICEMlSymR7A enables recombination between the ICEMlSymR7A attachment site attP and the 3' end of the phe-tRNA gene. Here we identified putative IntS attP arm (P) sites within the attP region and demonstrated that the outermost P1 and P5 sites demarcated the minimal region for efficient IntS-mediated integration. We also identified the ICEMlSymR7A origin-of-transfer (oriT) site directly upstream of the relaxase-gene rlxS. The ICEMlSymR7A conjugation system mobilised a plasmid carrying the cloned oriT to Escherichia coli in an rlxS-dependent manner. Surprisingly, an in-frame, markerless deletion mutation in the ICEMlSymR7A recombination directionality factor (excisionase) gene rdfS, but not a mutation in intS, abolished mobilisation, suggesting the rdfS deletion tentatively has downstream effects on conjugation or its regulation. In summary, this work defines two critical cis-acting regions required for excision and transfer of ICEMlSymR7A and related ICEs