Todd W. Sands

High cAMP in spores of Dictyostelium discoideum : association with spore dormancy and inhibition of germination

Signalling mechanisms involving cAMP have a well-documented role in the coordination of multicellular development and differentiation leading to spore formation in the social amoeba, Dictyostelium discoideum. The involvement of cAMP in the poorly understood developmental stages of spore dormancy and germination have been investigated in this study. Dormant spores contained up to 11-fold more cAMP than nascent amoebae. The spore cAMP levels were not constant, but typically underwent a surge at 14-18 d when spores acquired the ability to germinate spontaneously. The high cAMP levels decreased only during successful spore germination, i.e. emergence of nascent amoebae. The temporal pattern of cAMP decrease was complex and unique to the method of spore activation, supporting our hypothesis that exogenously (e.g. heat) activated and autoactivated spores germinate by different mechanisms. During heat-induced activation, transcription of acg (a gene encoding adenylyl cyclase associated with germination) correlated well with spore cAMP content. Young wild-type spores, incapable of spontaneous germination, maintained a uniformly high cAMP level, and spore cAMP levels also remained high if germination was inhibited. When activated spores were deactivated by applying increased osmotic pressure, cAMP concentrations rose and ultimately levelled off at the high levels typical of dormant spores. The correlation between high cAMP and failure to germinate was also evident when autoactivation was inhibited by the cAMP analogue, 8-bromo-cAMP. Also, spores from a strain (HTY217) with unrestrained protein kinase A activity were incapable of spontaneous germination. Overall, our experiments provide evidence for continued cAMP signalling in spores up to 18 d after sporulation and for linkages between elevated cAMP, spore deactivation and inhibition of spontaneous germination.

Development and pilot testing of a mobile health solution for asthma self-management: asthma action plan smartphone application pilot study.

BACKGROUND Collaborative self-management is a core recommendation of national asthma guidelines; the written action plan is the knowledge tool that supports this objective. Mobile health technologies have the potential to enhance the effectiveness of the action plan as a knowledge translation tool. OBJECTIVE To design, develop and pilot a mobile health system to support asthma self-management. METHODS The present study was a prospective, single-centre, nonrandomized, pilot preintervention-postintervention analysis. System design and development were guided by an expert steering committee. The network included an agnostic web browser-based asthma action plan smartphone application (SPA). Subjects securely transmitted symptoms and peak flow data daily, and received automated control assessment, treatment advice and environmental alerts. RESULTS Twenty-two adult subjects (mean age 47 years, 82% women) completed the study. Biophysical data were received on 84% of subject days (subject day = 1 subject × 1 day). Subjects viewed their action plan current zone of control on 54% and current air quality on 61% of subject days, 86% followed self-management advice and 50% acted to reduce exposure risks. A large majority affirmed ease of use, clarity and timeliness, and 95% desired SPA use after the study. At baseline, 91% had at least one symptom criterion for uncontrolled asthma and 64% had ≥2, compared with 45% (P=0.006) and 27% (P=0.022) at study close. Mean Asthma Quality of Life Questionnaire score improved from 4.3 to 4.8 (P=0.047). CONCLUSIONS A dynamic, real-time, interactive, mobile health system with an integrated asthma action plan SPA can support knowledge translation at the patient and provider levels.

Using a knowledge translation framework to implement asthma clinical practice guidelines in primary care

Quality problem International guidelines establish evidence-based standards for asthma care; however, recommendations are often not implemented and many patients do not meet control targets. Initial assessment Regional pilot data demonstrated a knowledge-to-practice gap. Choice of solutions We engineered health system change in a multi-step approach described by the Canadian Institutes of Health Research knowledge translation framework. Implementation Knowledge translation occurred at multiple levels: patient, practice and local health system. A regional administrative infrastructure and inter-disciplinary care teams were developed. The key project deliverable was a guideline-based interdisciplinary asthma management program. Six community organizations, 33 primary care physicians and 519 patients participated. The program operating cost was

Spirometry in Primary Care: An Analysis of Spirometry Test Quality in a Regional Primary Care Asthma Program

290/patient. Evaluation Six guideline-based care elements were implemented, including spirometry measurement, asthma controller therapy, a written self-management action plan and general asthma education, including the inhaler device technique, role of medications and environmental control strategies in 93, 95, 86, 100, 97 and 87% of patients, respectively. Of the total patients 66% were adults, 61% were female, the mean age was 35.7 (SD = ±24.2) years. At baseline 42% had two or more symptoms beyond acceptable limits vs. 17% (P< 0.001) post-intervention; 71% reported urgent/emergent healthcare visits at baseline (2.94 visits/year) vs. 45% (1.45 visits/year) (P< 0.001); 39% reported absenteeism (5.0 days/year) vs. 19% (3.0 days/year) (P< 0.001). The mean follow-up interval was 22 (SD = ±7) months. Lessons learned A knowledge-translation framework can guide multi-level organizational change, facilitate asthma guideline implementation, and improve health outcomes in community primary care practices. Program costs are similar to those of diabetes programs. Program savings offset costs in a ratio of 2.1:1

Comparison of Asthma Control Criteria: Importance of Spirometry

BACKGROUND Primary care office spirometry can improve access to testing and concordance between clinical practice and asthma guidelines. Compliance with test quality standards is essential to implementation. OBJECTIVE To evaluate the quality of spirometry performed onsite in a regional primary care asthma program (RAP) by health care professionals with limited training. METHODS Asthma educators were trained to perform spirometry during two 2 h workshops and supervised during up to six patient encounters. Quality was analyzed using American Thoracic Society (ATS) 1994 and ATS⁄European Respiratory Society (ERS) 2003 (ATS⁄ERS) standards. These results were compared with two regional reference sites: a primary care group practice (Family Medical Centre [FMC], Windsor, Ontario) and a teaching hospital pulmonary function laboratory (London Health Sciences Centre [LHSC], London, Ontario). RESULTS A total of 12,815 flow-volume loops (FVL) were evaluated: RAP - 1606 FVL in 472 patient sessions; reference sites - FMC 4013 FVL in 573 sessions; and LHSC - 7196 in 1151 sessions. RAP: There were three acceptable FVL in 392 of 472 (83%) sessions, two reproducible FVL according to ATS criteria in 428 of 469 (91%) sessions, and 395 of 469 (84%) according to ATS⁄ERS criteria. All quality criteria - minimum of three acceptable and two reproducible FVL according to ATS criteria in 361 of 472 (77%) sessions and according to ATS⁄ERS criteria in 337 of 472 (71%) sessions. RAP met ATS criteria more often than the FMC (388 of 573 [68%]); however, less often than LHSC (1050 of 1151 [91%]; P<0.001). CONCLUSIONS Health care providers with limited training and experience operating within a simple quality program achieved ATS⁄ERS quality spirometry in the majority of sessions in a primary care setting. The quality performance approached pulmonary function laboratory standards.

Development and implementation of an electronic asthma record for primary care: integrating guidelines into practice.

Aims. To compare the measurements of asthma control using Canadian Thoracic Society (CTS) Asthma Management Consensus Summary and Global Initiative for Asthma (GINA) guidelines composite indices with and without spirometry. Methods. Asthma control parameters were extracted from electronic medical records (EMRs) of patients ≥6 years old at two primary care sites. Asthma control ratings calculated according to CTS and GINA criteria were compared. Results. Data were available from 113 visits by 93 patients, aged 6–85 years (38.7 ± 24.8; mean ± SD). The proportion of visits at which individuals’ asthma was completely controlled was 22.1% for CTS symptoms only and 9.7% for CTS with spirometry (p < .01); and 17.7% versus 14.1% for GINA symptoms only versus symptoms with spirometry (p = .125). Conclusions. Asthma control ratings using GINA and CTS criteria are discordant in more than half of the patients deemed “in control” by at least one scale. Differences in the spirometry criterion threshold are primarily responsible for this discordance. Failure to include spirometry as part of the control index consistently overestimates asthma control and may underestimate future risk of exacerbations.

A computer program to assist in the choice of restriction endonucleases for use in DNA analyses

Abstract Rationale: Evidence-based practice may be enhanced by integrating knowledge translation tools into electronic medical records (EMRs). We examined the feasibility of incorporating an evidence-based asthma care map (ACM) into Primary Care (PC) EMRs, and reporting on performance indicators. Methods: Clinicians and information technology experts selected 69 clinical and administrative variables from the ACM template. Four Ontario PC sites using EMRs were recruited to the study. Certified Asthma Educators used the electronic ACM for patient assessment and management. De-identified data from consecutive asthma patients were automatically transmitted to a secure central server for analysis. Results: Of the four sites recruited, two sites using “stand-alone” EMR systems were able to incorporate the selected ACM variables into an electronic format and participate in the pilot. Data were received on 161 visits by 130 patients aged 36.5 ± 26.9 (mean ± SD) (range 2–93) years. Ninety-four percent (65/69) of the selected ACM variables could be analyzed. Reporting capabilities included: individual patient, individual site and aggregate reports. Reports illustrated the ability to measure performance (e.g. number of patients in control, proportion of asthma diagnoses confirmed by an objective measure of lung function), benchmark and use EMR data for disease surveillance (e.g. number of smokers and the individuals with suspected work-related asthma). Conclusions: Integration of this evidence-based ACM into different EMRs was successful and permitted patient outcomes monitoring. Standardized data definitions and terminology are essential in order for EMR data to be used for performance measurement, benchmarking and disease surveillance.

Comparisons of genetic variability detected among mouse blood proteins using one- and two-dimensional electrophoreses

Type II restriction endonucleases cleave double stranded DNA molecules at sites characterized by one or more sets of nucleotide pairs sequences. These digestions are essential in such procedures as DNA cloning, DNA sequencing and restriction fragment length polymorphism (RFLP) analyses. A large number of enzymes with different sequence specificities are available. To date, most choices of restriction endonucleases have been made by trial and error. A computer program, REDI, has been developed that predicts the ability of a particular restriction enzyme to detect mutations. Characteristics of both the restriction endonuclease used and the DNA being cut are incorporated as variables in the program. The program was tested using mouse mitochondrial DNA (mtDNA) and bacteriophage lambda DNA because these have been sequenced and are well characterized. REDI was strongly correlated (rs = +0.862, n = 11, P less than 0.001) with mouse mtDNA RFLP detected by Ferris et al. [1] (Genetics, 105 (1983) 681-721). Even though predictions may be altered by a non-random association of nucleotides, which varies among DNA molecules, the predictions increase the probability of selecting the most efficient enzymes for use in the analysis of a particular DNA molecule.

High Performance Computing Systems and Applications

Comparisons of the sensitivities of one-dimensional (1D) and two-dimensional (2D) electrophoreses to detect genetic variability have generally shown that the 2D approach appears to be two- to five-fold less sensitive than conventional 1D approaches. Concerns about the validity of this conclusion have arisen because such comparisons have involved mainly enzymic proteins in 1D approaches versus a complex mixture of soluble proteins in most 2D analyses. Comparisons involving the absolute number of variants detected, using 1D and 2D sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE), denatured mouse blood proteins isolated from C3HeB/FeJ and C57 B1/6J inbred strains of mice, and highly sensitive silver staining, indicate that the latter uncovers at least as much variability as the former. Although the relative percentage of variable bands (1D SDS-PAGE) was greater than the relative percentage of variable spots (2D SDS-PAGE) when proteins of intact erythrocytes were surveyed, both techniques uncovered approximately equal percentages of variable proteins when the mouse erythrocyte proteins were partitioned into membrane and lysate components. Therefore, the simpler 1D SDS-PAGE was found to be as effective as 2D SDS-PAGE in detecting protein variability. Since 1D SDS-PAGE separates proteins primarily on the basis of molecular weight and to a lesser degree on other primary protein sequence alterations, much of the variability observed by 2D SDS-PAGE may be due to these same features and unit charge differences may not play a significant role in detecting variability in the proteins studied. This differs from enzymic proteins, where such charge differences appear to be responsible for much of the variability. This study also indicated that decreasing the number of proteins in samples (membranes and lysates vs whole erythrocytes) increased the ability of both of these techniques to resolve differences. Mating studies indicated that most of the differences detected with both techniques were inherited and were not artifacts.

Network Access Capability to Systems as A Factor in Distributed and Cluster Computing

High Performance Computing Systems and Applications contains fully refereed papers from the 15th Annual Symposium on High Performance Computing. These papers cover both fundamental and applied topics in HPC: parallel algorithms, distributed systems and architectures, distributed memory and performance, high level applications, tools and solvers, numerical methods and simulation, advanced computing systems, and the emerging area of computational grids. High Performance Computing Systems and Applications is suitable as a secondary text for graduate level courses, and as a reference for researchers and practitioners in industry.