Dawn L. MacLellan
Dalhousie University
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Featured researches published by Dawn L. MacLellan.
The Journal of Urology | 2011
Ashley Cox; Lynn M. Breau; Liette Connor; P. Daniel McNeely; Peter Anderson; Dawn L. MacLellan
PURPOSE Transitioning care of patients with spina bifida to adult centers poses a challenge. We sought patient and parent perspectives on the transition process at our center and correlated these perspectives with medical outcomes. MATERIALS AND METHODS Patients who attended the adult spina bifida clinic at our institution were invited to complete SF-36®, the Ambulatory Care Experience Survey and a Transition of Care Survey. Urological and neurosurgical medical outcomes were correlated with health status, clinic experience and perspectives on the transition process. Statistical analysis was done using SPSS®, version 16.0. RESULTS Of 105 patients with spina bifida 24 participated in the study. SF-36 results showed that the physical health domain correlated with lack of employment (p = 0.006). Patients whose parents completed the surveys on their behalf were more likely to have physical limitations than the patients who completed surveys (p = 0.011). Urological and neurosurgical outcomes did not significantly affect SF-36, Ambulatory Care Experience Survey or Transition of Care Survey scores in this patient population. Patients and caregivers identified similar key elements and barriers in the transition process. Satisfaction with care at the pediatric center was higher than at the adult center. CONCLUSIONS Transitioning care of patients with spina bifida from pediatric to adult care poses challenges for the health care system. Medical outcomes do not impact the patient perspective of the transition process. To optimize the transition of care we must address the barriers identified by patients and their caregivers.
Journal of Pediatric Urology | 2009
William H. Carlson; Stephen Kisely; Dawn L. MacLellan
OBJECTIVE To determine maternal and fetal demographic factors which predict the risk of increasing severity of hypospadias. PATIENTS AND METHODS A population-based study using the Nova Scotia Atlee Perinatal Database was performed. Demographic variables of mothers and boys with hypospadias were obtained from 1980 to 2007 inclusive. Hypospadias was graded by the position of the urinary meatus as glanular, coronal, shaft, or proximal to shaft. Maternal and fetal risk factors for hypospadias severity were compared using logistic regression. RESULTS The total number of male pregnancy and birth records during the study period was 130,796. The total number of cases of hypospadias was 995, yielding an incidence of 0.76%. The severity of hypospadias was graded as glanular in 428 (77.8%); coronal in 77 (14%); penile shaft in 34 (6.2%); and proximal to the penile shaft in 12 (2.2%). The severity of hypospadias was not graded in 445 cases. Low birth weight, low gestational age and maternal age were associated with increased severity of hypospadias, but only maternal age (P<0.03) when logistic regression was performed. Limitations included self-reporting for some parameters, such as smoking, and lack of data, such as for the use of assisted reproductive technologies. CONCLUSIONS Advanced maternal age was associated with increased severity of hypospadias in our population.
Molecular BioSystems | 2011
Dawn L. MacLellan; Diane Mataija; Alan A. Doucette; Weei Yuarn Huang; Chantale Langlois; Greg Trottier; Ian W. Burton; John A. Walter; Tobias K. Karakach
Urinary tract obstruction (UTO) results in renal compensatory mechanisms and may progress to irrecoverable functional loss and histologic alterations. The pathophysiology of this progression is poorly understood. We identified urinary metabolite alterations in a rodent model of partial and complete UTO using (1)H nuclear magnetic resonance ((1)H-NMR) spectroscopy. Principal component analysis (PCA) was used for classification and discovery of differentiating metabolites. UTO was associated with elevated urinary levels of alanine, succinate, dimethylglycine (DMG), creatinine, taurine, choline-like compounds, hippurate, and lactate. Decreased urinary levels of 2-oxoglutarate and citrate were noted. The patterns of alteration in partial and complete UTO were similar except that an absence of elevated urinary osmolytes (DMG and hippurate) was noted in complete UTO. This pattern of metabolite alteration indicates impaired oxidative metabolism of the mitochondria in renal proximal tubules and production of renal protective osmolytes by the medulla. Decreased production of osmolytes in complete obstruction better elucidates the pathophysiology of progression from renal compensatory mechanisms to irrecoverable changes. Further confirmation of these potential biomarkers in children with UTO is necessary.
Proteomics Clinical Applications | 2009
Diane Mataija‐Botelho; Patrick Murphy; Devanand M. Pinto; Dawn L. MacLellan; Chantale Langlois; Alan A. Doucette
Inherent to the biomarker discovery process is a comparative analysis of physiological states. It is therefore critical that the proteome detection protocol does not bias the analysis. With urine, the sediment portion, obtained upon thawing frozen urine, is routinely discarded prior to proteome analysis. However, our results demonstrate that such a practice inadvertently induces bias, having significant implications in the biomarker discovery process. We present the first proteome investigation of human urinary sediments, identifying 60 proteins in this phase by MS. Many sediment proteins were also detected in the urinary supernatant, indicating that several proteins partition between the two phases. This partitioning is dependant on the pH of the sample, as well as the degree of sample agitation. As a consequence of discarding the sediment portion of urine, the concentration of potential candidate biomarkers in the supernatant phase will be altered or, in other instances, may be completely removed from the sample. To minimize this, the pH of all samples should first be normalized, and the samples vigorously vortexed prior to discarding the sediments. For more comprehensive biomarker investigations, we suggest that urinary sediments be analyzed along with the supernatant proteins.
Journal of Proteomics | 2015
Andrew M.J. Crowell; Dawn L. MacLellan; Alan A. Doucette
UNLABELLED Protein precipitation with organic solvent is an effective means of depleting contaminants such as sodium dodecyl sulfate (SDS), while maintaining high analyte recovery. Here, we report the use of a disposable two-stage spin cartridge to facilitate isolation of the precipitated protein, with subsequent enzyme digestion and peptide cleanup in the cartridge. An upper filtration cartridge retains over 95% of the protein (10 μg BSA), with 99.75% detergent depleted from a sample initially containing 2% SDS. Following precipitation, a plug attached to the base of the filtration cartridge retains the solution to enable tryptic digestion in the vial, while a solid phase extraction cartridge attached to the base of the filter facilitates peptide cleanup post-digestion. A GELFrEE fractionated Escherichia coli proteome extract processed with the spin cartridge yields similar protein identifications compared to controls (226 vs 216 for control), and with an increased number of unique peptides (1753 vs 1554 for control). The device is applied to proteome characterization of rat kidneys experiencing a surgically induced ureteral tract obstruction, revealing several statistically altered proteins, consistent with the morphology and expected pathophysiology of the disease. BIOLOGICAL SIGNIFICANCE Conventionally, protein precipitation involves extended centrifugation to pellet the sample, with careful pipetting to remove the supernatant without disturbing the pellet. The method is not only time consuming but is highly subject to the skill of the individual, particularly at lower protein concentrations where the pellet may not be visible. As such, protein precipitation is often overlooked in proteomics, favoring column-based approaches to concentrate or purify samples. Here, all aspects of sample manipulation are integrated into a simple disposable cartridge. The device enables SDS depletion, sample preconcentration, resolubilization, derivatization, digestion, and peptide cleanup in a highly repeatable and easily multiplexed format. The device is ideally suited for comparative proteome studies. Antenatal hydronephrosis is a congenital disorder affecting 1-5% of all pregnancies, and can require surgical intervention to avoid loss of renal function. Using our device, we investigated the impact of hydronephrosis on the kidneys in a surgically induced animal model of the disease. Proteome analysis points to decreased metabolic activity in the obstructed kidney, with upregulation of proteins involved in cytoskeletal organization. This article is part of a Special Issue entitled: Protein dynamics in health and disease. Guest Editors: Pierre Thibault and Anne-Claude Gingras.
Journal of Proteomics | 2014
Dennis J. Orton; Alan A. Doucette; Geoffrey N. Maksym; Dawn L. MacLellan
UNLABELLED Urinary tract obstruction (UTO) is a commonly noted disorder on prenatal ultrasound that has the potential to lead to permanent loss of renal function. To study the molecular processes of the disease, an in vitro model has been developed which involves mechanical stretch of proximal tubule cells grown on flexible plates which mimics the physiological conditions during UTO. This study employs a one dimensional SDS-PAGE fractionation procedure, followed by in-gel digest and LC-MS/MS analysis in a semi-quantitative experiment using spectral counting to relatively quantify changes in protein expression following the established model of UTO. Quantitative analysis shows 317 of the 1630 identified proteins express altered abundance, with 135 increased and 182 decreased in abundance as a result of stretch. Gene ontology (GO) and KEGG annotations implicate a number of physiological processes that have been previously shown in addition to some potentially novel processes in UTO. The quantitative proteomic analysis we performed here provides a more complete characterization of changes in protein abundance as a result of stretch than previous studies, and provides a number of previously undescribed proteins in proximal tubule cells that may play a role in UTO. BIOLOGICAL SIGNIFICANCE Urinary tract obstruction (UTO) is a commonly noted abnormality on prenatal ultrasound that can either resolve spontaneously or require surgical intervention to prevent permanent renal damage or loss of function. While targeted studies of UTO have shown a number of pathological responses in proximal tubule cells, there are currently no large-scale quantitative studies that aim to elucidate a global cellular response. This study uses a semi-quantitative approach and applies a well characterized model of UTO to determine a number of cellular processes affected by UTO simulation and identifies a number of proteins with altered abundance that have not been noted previously in UTO. This article is part of a Special Issue entitled: Can Proteomics Fill the Gap Between Genomics and Phenotypes?
Urology | 2016
Jon J. Duplisea; Rodrigo L.P. Romao; Dawn L. MacLellan; Ashley Cox; Peter Anderson
OBJECTIVE To establish the time to development of urological issues over time in adult spina bifida (SB) patients. MATERIALS AND METHODS This is a retrospective study of adult patients attending a multidisciplinary adult SB clinic from 2000 to 2013. Patient age, sex, number of clinic visits, and length of follow-up were recorded. For each unique visit, presence of symptoms, type of urological issue (if any), and time lapsed since last appointment were obtained. The interval between the development of urological issues was assessed using a time-to-event analysis. RESULTS One hundred twenty-three patients (46% male, 54% female, median age 26.8years) were followed for a median of 48 months, contributing to 586 unique clinic visits. Urological issues were identified in 109 patients (88.5%) during 267 visits (46%), and of those 21% were asymptomatic. In symptomatic patients, the median time to present with a urological issue was 12 months. Among the asymptomatic cases, 12%, 23%, and 34% had developed a urological issue at 12, 24, and 36 months of follow-up, respectively. Eighty-one percent of the urological issues seen in the clinic required some form of treatment or intervention. The treatment or intervention in 56% of asymptomatic urological issues was surgery. CONCLUSION Most adult SB patients with urological issues are symptomatic by 2 years of follow-up; however, over time the proportion of asymptomatic patients with urological issues rises steadily, reaching a worrisome 34% at 3 years. Closer follow-up seems warranted.
Canadian Medical Association Journal | 2017
Alexandra Hudson; Rodrigo L.P. Romao; Dawn L. MacLellan
In children less than two years of age, a fever (> 39°C) without an apparent source is the most common sign of urinary tract infection (likelihood ratio 4.0).[1][1] Abnormal or strong urinary odour has poor predictive accuracy (i.e., sensitivity 43%, specificity 48%; Appendix 1, available at [www.
Urology | 2008
Marie-Claude Grégoire; Dawn L. MacLellan; G. Allen Finley
Pediatric Clinics of North America | 2006
Dawn L. MacLellan; David A. Diamond