bluuebunny/crossref_metadata_2025 huggingface dataset:
66. Innovation in the academic half-day CanMEDS medical expert competency for residency educations
Authors: Rajani H. R. , Good C.
Published: May 2017

Over the past decade we have attempted various iterations of the academic half-day, but recurring trainee complaints of only didactic sessions, a parallel resident-directed “Nelsons” rounds, and low attendance necessitated a reconsideration of the approach.

After discussion with the postgraduate trainees we divided the academic year into two blocks. An initial 8 week “summer program” with 24 student contact hours, focuses on the introduction to and review of common, critical care and emergency pediatric issues. The following 40 weeks has 120 student contact hours. Two thirds of the time is directed at the CanMEDS Medical Expert Core Competency. The postgraduate trainees have developed a three year core knowledge curriculum. The 200 “core” topics are mapped onto four international curricula; the RCPSC’s Objectives of Training and Specialty Training Requirements in Pediatrics using the Systems-Based Educational Objectives in the Core Program in Pediatrics, the American Board of Pediatrics – General Pediatrics Outline, and the Royal College of Pediatrics & Child Health (RCPCH) Framework of Competencies for Basic Specialist Training, and Core Higher Specialist Training in Paediatrics.

The two hour Medical Expert session is divided equally into a postgraduate trainee didactic presentation, and a collaborator case-based learning session. Six weeks prior to the scheduled session the trainee and the assigned faculty collaborator receive the core Medical Expert topic mapped to the four international curricula. The pediatric trainee develops a didactic presentation along with a two page summary. The collaborator, a resource for the trainee’s didactic presentation, develops three clinical cases that emphasize core knowledge, and attends as a Medical Expert resource person.

We are currently surveying the postgraduate trainees and faculty about this international-based core medical expert program of study.
67. Loving your child to death: Considerations of the care of chronically-ill children and euthanasia in Emil Sher's Mourning Dove and implications for medical educations
Authors: Mukhida K.
Published: May 2017

How do parents cope when their child is ill or dying, when he or she experiences constant pain or suffering? What do parents think of the contributions that medical professionals make to the care of their chronically or terminally ill child? Is it possible for a parent to love a child so much that the child is wished dead? The purpose of this paper is to explore those questions and aspects of the care of chronically or terminally ill children using Mourning Dove’s portrayal of one family’s attempt to care for their ill daughter. A play written by Canadian playwright Emil Sher, Mourning Dove is based on the case of Saskatchewan wheat farmer Robert Latimer who killed his 12 year old daughter Tracy who suffered with cerebral palsy and lived in tremendous pain. Rather than focusing on the medical or legal aspects of the care of a chronically ill child, the play offers a glimpse into how a family copes with the care of such a child and the effects the child’s illness has on a family. Reading and examination of non-medical literature, such as Mourning Dove, therefore serve as a useful means for medical professionals to better understand how illness affects and is responded to by patients and their families. This understanding is a prerequisite for them to be able to provide complete care of children with chronic or terminal illnesses and their families.

Nuutila L, Salanterä S. Children with long-term illness: parents’ experiences of care. J Pediatr Nurs 2006; 21(2):153-160.

Sharman M, Meert KL, Sarnaik AP. What influences parents’ decisions to limit or withdraw life support? Pediatr Crit Care Med 2005; 6(5):513-518.

Steele R. Strategies used by families to navigate uncharted territory when a child is dying. J Palliat Care 2005; 21(2):103-110.
68. The resident experience in a large urban teaching setting: Results of the 2005-2006 resident exit survey, University of Torontos
Authors: Tenn-Lyn N. , Verma S. , Zulla R.
Published: May 2017

We developed and implemented an annual online survey to administer to residents exiting residency training in order to (1) assess the quality of the residency experience and (2) identify areas of strength and areas requiring improvement. Long-term goals include program planning, policy-making and maintenance of quality control. Survey content was developed from an environmental scan, pre-existing survey instruments, examination of training criteria established by the CFPC and the CanMEDS criteria established by the RCPSC. The survey included evaluation benchmarks and satisfaction ratings of program director and faculty, preparation for certification and practice, quality of life, quality of education, and work environment.

The response rate was 28%. Seventy-five percent of respondents were exiting from Royal College training programs. Results of descriptive statistics determined that the overall educational experience was rated highly, with 98.9% of respondents satisfied or very satisfied with their overall patient care experience. Ninety-six percent of respondents were satisfied or very satisfied with the overall quality of teaching. Preparation for practice was identified as needing improvement, with 26% and 34% of respondents giving an unsatisfactory rating to career guidance and assistance with finding employment, respectively. Although 80% of respondents reported receiving ongoing feedback and 84% discussed their evaluations with their supervisors, only 38% of evaluations were completed by the end of the rotation.

The results indicate that residents are generally satisfied with their experiences during residency training, especially with their overall educational experience. Areas of improvement include preparation for practice and timeliness of evaluations. Further iterations of this survey are needed to refine the instrument, identify data trends and maintain quality control in residency training programs.

Frank JR (ed.). The CanMEDS competency framework: better standards, better physicians, better care. Ottawa: The Royal College of Physicians and Surgeons of Canada, 2005.

Merritt, Hawkins and Associates. Summary Report: 2003 Survey of final-year medical residents. http://www.merritthawkins.com/pdf/MHA2003residentsurv.pdf. Accessed May 1, 2006.

Regnier K, Kopelow M, Lane D, Alden A. Accreditation for learning and change: Quality and improvement as the outcome. The Journal of Continuing Education in the Health Professions 2005; 25:174-182.
72. Evaluatation of an innovative mentorship program - Multilevel mentorship model - Does it meet the needs of residents?
Authors: Elliott C. T.J. , Buxton J. , Froese S.
Published: May 2017

The UBC community medicine mentorship program was established in 2003 and is continually evaluated. In response to resident feedback, we developed an innovative mentorship model that involves mentorship of junior residents by both mentors from the professional community and senior residents. This new multilevel mentorship model (MMM) was implemented in 2005. It was evaluated for its ability to (1) foster professional and personal relationships among mentors and mentees, (2) help residents develop career goals and (3) support residents who were having challenges in the program.

The program was evaluated using an on-line survey, with both Likert scale and short-answer responses. The survey was completed by 10/13 (77%) residents, 7/13 (54%) community medicine professionals (CMPs). For the first level, CMP-resident mentorship, 9/10 residents and 5/7 CMPs agreed that a positive relationship was maintained, and that they benefited from the relationship; 8/10 residents agreed that career counseling occurred. Two of the three residents who had conflict in the program felt that they were supported by their CMP mentor. Mentorship was a positive experience even for two residents who left the program. For the second level, senior-junior resident mentorship, all relationships started within the first month of the program and all residents agreed that a positive relationship was maintained throughout the year. Career counseling occurred in 2/3 junior-senior resident pairs. All three residents agreed that their resident mentor supported them during a conflict. Several resident- and CMP-mentors described heightened awareness of issues that residents face in training.

The multilevel mentorship model has considerable potential for fostering mentoring relationships, career planning, and helping residents overcome the challenges of residency.

Barondess JA. Mentoring in biomedicine. J Lab Clin Med 1197; 129:487-91.

Jackson VA, Palepu A, Szalacha L, Caswell C, Carr PL, Inui T. “Having the right chemistry”: a qualitative study of mentoring in academic medicine. Acad Med 2003; 78:328-334.

Williams LL, Levine JB, Malhotra S, Holtzheimer P. The good-enough mentoring relationship. Academic Psychiatry 2004; 28:111-115.
73. "I just don't want to kill anybody": The first six months of postgraduate trainings
Authors: Martin D. , Takahashi S. Glover
Published: May 2017

This paper describes a qualitative study that used focus groups and individual interviews to explore newly graduated medical students’ experience of the first six months of a postgraduate training programme. This study explored the residents’ concerns, changes that occurred and the influences the residents attributed to those changes during the first six months, this paper focuses on the residents’ experience of responsibility during this initial training period. Residents felt there was a huge leap in responsibility when they made the transition from being a medical student to being a doctor, specifically in the areas of knowledge, practice management, and relationships. This paper describes how the residents felt there was a disconnect between their experience of responsibility as a medical student and their experience of responsibility as a doctor. Residents were concerned they lacked the necessary medical experience and expertise for someone wearing the title “doctor”. It was not until residents felt relatively confident that they were not going to harm patients with their knowledge that they were able to begin the process of understanding what it meant to be the family physician, which allowed them to begin identifying with the role of family medicine resident. This process took weeks for some residents and several months for others. This study lays the groundwork for better understanding the transition experience from undergraduate to postgraduate training from the resident’s perspective. This paper focuses specifically on the concerns residents had adjusting to their new responsibilities and the implications this might have for medical educators and curriculum developers.

Hirsh DA., Ogur B, Thibault GE, Cox M. “Continuity” as an Organizing Principle for Clinical Education Reform. The New England Journal of Medicine 2007 (Feb):858-866.

Kendall ML, Hesketh EA, Macpherson SG. The learning environment for junior doctor training – what hinders, what helps. Medical Teacher 2005; 25:619 – 24.

Luthy C, Perrier A, Perrin E, Cedrascht C, Allaz AF. Exploring the major difficulties perceived by residents in training: a pilot study. Swiss Medical Weekly 2004; 134:612-17.
Atomoxetine, but not paroxetine, blocks norepinephrine reuptake in depressed patientss
Authors: Aldosary F. , Tremblay P. , Hébert C. , Blier P.
Published: May 2017

Purpose: Paroxetine is a potent serotonin (5-HT) reuptake inhibitor. However, a purported norepinephrine (NE) reuptake blockade action remains to be established. Atomoxetine is a potent NE reuptake inhibitor with the indication of attention deficit hyperactivity disorder (ADHD). The present study was aimed at confirming a NE reuptake inhibitory action with ascending doses of atomoxetine and possibly with paroxetine in depressed patients.

Methods: Patients were randomized to escalating doses of either paroxetine (20 to 50 mg/day), or atomoxetine (25-80 mg/day) in a four to six week period. Inhibition of NE reuptake was assessed using the attenuation of systolic blood pressure (SBP) elevations produced by intravenous injections of tyramine. Tyramine penetrates into peripheral NE terminals via the NE reuptake transporter and releases NE. Then, NE acts on the vascular adrenoceptors, which causes an elevation of SBP. Drugs that block NE reuptake attenuate the pressor effects of tyramine. Two-way ANOVA for repeated measures for doses of tyramine and treatments were used to assess the effects of the different drug regimens on the pressor response to loads of 3–6 mg of tyramine. Sixteen patients with unipolar major depressive disorder were assessed weekly after increasing the dose of paroxetine (9 patients) and atomoxetine (7 patients).

Results: Atomoxetine exerted a robust inhibition of the tyramine response, starting at the dose of 25mg/day in a dose-dependent pattern. Neither the low nor the high doses of paroxetine altered the tyramine pressor response.

Conclusions: These results provide evidence that atomoxetine started significantly inhibiting NE reuptake at subtherapeutic dose for ADHD, whereas paroxetine leaves the activity of the NE transporter unaltered, even at the highest recommended dose for depression.
The role of AMP-activate protein kinase (AMPK) in the regulation of cardiac hypertrophy
Authors: Chan Anita Y M , Soltys Carrie-Lynn M , Dyck Jason RB
Published: May 2017

Backgrond: The polyphenol resveratrol has been attributed to some of the cardioprotective effects of red wine consumption, including the ability to inhibit hypertrophy via its antioxidant properties. A recent discovery in hepatocytes showed that resveratrol can activate AMP-activated protein kinase (AMPK), a key regulator of cellular energy homeostasis. However, it is currently unknown whether resveratrol can also activate cardiac AMPK and the functional consequence of this. As we have shown that activation of AMPK inhibits protein synthesis associated with cardiac hypertrophy, we hypothesized that an additional mechanism by which resveratrol inhibits hypertrophy is via AMPK activation.

Methods: To investigate this, neonatal rat cardiac myocytes were treated with vehicle (Veh) or 50 µM resveratrol (Resv) for 24 hours and 10 µM phenylephrine (PE) to induce hypertrophy. Contributors of the hypertrophic response, such as protein synthesis and specific intracellular signalling pathways, were measured using [3H]-phenylalanine incorporation and immunoblot analysis, respectively.

Results: Activation of AMPK was achieved with resveratrol even in the presence of phenylephrine, as shown by increased AMPK phosphorylation (Veh+PE = 0.69±0.06 vs Resv+PE = 1.57±0.29 arbitrary units, p < 0.01). Resveratrol also significantly decreased protein synthesis induced by phenylephrine (Veh+PE = 45702.5±5252.9 vs Resv+PE = 32929.0±4512.9 disintegrations per minute, p < 0.05). This was associated with reduced activities of regulators of protein synthesis, namely p70S6 kinase and eukaryotic elongation factor-2 (eEF2). Specifically, resveratrol countered the effects of phenylephrine by blunting the increase in p70S6 kinase phosphorylation while partially restoring eEF2 phosphorylation. Furthermore, resveratrol dramatically decreased nuclear factor of activated T-cells (NFAT) promoter activity, as shown by reduced luciferase activity driven by a NFAT-responsive promoter (Veh+PE = 171100±7881 vs Resv+PE = 27530±5975 luciferase activity, p < 0.001).

Conclusions: As the calcineurin-NFAT pathway is thought to be involved in pathological hypertrophy, this provides further evidence that AMPK activation has therapeutic potential, and shows another mechanism by which resveratrol can prevent hypertrophic growth.
A JNK-dependent switch determines the oncogenic or tumor suppressor activity of ILKs
Authors: Durbin A D , Somers G R , Forrester M , Hannigan G E , Malkin D
Published: May 2017

Background: Integrin-linked kinase (ILK) is a potent intracellular kinase involved in the regulation of multiple proliferation and survival kinases, including protein kinase B/Akt, glycogen synthase kinase-3β (GSK3β) and extracellular signal-regulated kinases 1 and 2 (ERK1/2). Evidence suggests ILK is overexpressed and acts oncogenically in a wide variety of primary tumors and genetic models, resulting in induction of tumor cell proliferation, migration, adhesion and angiogenic behaviours. Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma of childhood. Histological subclassification of RMS yields two major variants, embryonal (ERMS) and alveolar (ARMS). ERMS, as well as multiple other tumors including breast and lung carcinoma, are commonly associated with loss of heterozygosity at 11p15.5, a region harboring the ILK locus.

Methods: We utilized cell culture and primary tumors to examine the expression and function of ILK.

Results: We demonstrate differential expression of ILK between ERMS and ARMS tumors in vitro and in vivo. RNAi to ILK induces potent gene silencing, with decreases in the phosphorylation of multiple ILK targets. ILK silencing induced inhibition of ARMS, and a contrasting potent stimulation of ERMS cell growth in survival and proliferation assays. These effects were reversed by adenoviral overexpression of ILK in multiple RMS and other tumor cell lines. Moreover, ILK silencing has multiple signaling effects, including induction of cell cycle progression through bmi-1and p16INK4a in ERMS with repression in ARMS, and phosphorylation of c-Jun NH2 terminal kinase (JNK) and c-Jun in ERMS and repression in ARMS cells. Coupling of JNK inhibition with ILK knockdown in ERMS cells inverted the ILK knockdown phenotype, resulting in a significant loss of cell proliferation.

Conclusions: Together, these data confirm the oncogenic role of ILK in alveolar rhabdomyosarcoma, and suggest a novel tumor-suppressive role for ILK signaling in embryonal rhabdomyosarcoma, mediated through the novel ILK target axis, JNK-c-Jun.
Abnormal neurogensis in the hippocampus of a mouse model of fragile X syndromes
Authors: Eadie B , Christie B
Published: May 2017

Fragile X syndrome is the most common inherited form of mental retardation. It is a neurodevelopmental disorder that is similar in clinical presentation to autism spectrum disorder. However, unlike autism, Fragile X syndrome is caused by the silencing of a single gene, and in recent years, a mouse model of Fragile X syndrome has been generated by deletion of the Fmr1 gene. Surprisingly, a clear neurobiological basis for the learning impairment observed in both these knockout mice and patients has been difficult to elucidate. We hypothesized that neurogenesis, a process that continues into adulthood in the hippocampus, may be abnormal in this syndrome. Support for such a hypothesis comes from the findings that these new neurons may disproportionately contribute to synaptic plasticity in networks engaged during learning and memory. We have shown that the survival of new cells in the hippocampus of young Fmr1 knockout mice is significantly decreased in the ventral hippocampus, a sub-region which may be more involved with emotional, rather than, spatial memory. Further experiments are being conducted to assess the differentiation of these new cells into neurons and glia. We are also characterizing the normal expression of the Fmr1 gene product, FMRP, across the phases of neurogenesis in control mice. In conclusion, we have discovered a clear impairment in a process that may be critical to emotionally-significant learning and memory in a mouse model of Fragile X syndrome.
Targeted deletion of discoidin domain receptor 1 (Ddr1) decreases atherosclerosis, reduces inflammation and accelerates matrix accumulation in LDL receptor deficient mices
Authors: Franco Christopher , Hou Guangpei , Vogel Wolfgang , Bendeck Michelle
Published: May 2017

Background: Collagens are abundant within the atherosclerotic plaque where they contribute to lesion volume, mechanical stability, and influence cellular behaviour. The discoidin domain receptor 1 (DDR1), a receptor tyrosine kinase that binds multiple collagen subtypes, has been observed in atheromata of non-human primates, but its function during atherogenesis is unclear.

Methods: To examine the role of DDR1 during atherosclerotic plaque development, we generated Ddr1+/+;Ldlr-/- and Ddr1-/-;Ldlr-/- mice and fed them an atherogenic diet for 12 or 24 weeks.

Results: Targeted deletion of Ddr1 resulted in a 50-60% reduction in atherosclerotic lesion area in the descending aorta at both 12 and 24 weeks. Atherosclerotic plaques from Ddr1-/-;Ldlr-/- mice demonstrated a 49% decrease in the area occupied by macrophages at 12 weeks, however, plaque SMC content was unchanged. We also observed accelerated deposition of fibrillar collagen and elastin in Ddr1-/-;Ldlr-/- plaques with a 36% and 45% increase at 12 weeks, respectively. Ddr1-/-;Ldlr-/- mice also demonstrated an early reduction in situ gelatinolytic activity in lesions and gelatin zymography revealed reduced MMP-2 activity at 12 weeks. Finally, mRNA expression analysis of laser microdissected plaques demonstrated enhanced expression of type I collagen and elastin, and reduced collagenase expression at 12 weeks. Moreover, mRNA expression of both MCP-1 and VCAM-1 was reduced in Ddr1-/-;Ldlr-/- plaques suggesting a novel role for DDR1 in the regulation of vascular inflammation.

Conclusion: Our data support a role for DDR1 as a positive regulator of atherosclerosis; capable of influencing both inflammation and matrix turnover early in plaque development, and when inhibited can result in a persistent reduction in atherosclerosis.
A screen for suppressors of apoptosis identifies a novel gain of function mutation in drosphilia RAS1s
Authors: Gafuik C , Agapite J , Steller H
Published: May 2017

Background: Apoptosis is a morphologically distinct, genetically programmed form of cell death that is evolutionarily highly conserved amongst multi-cellular eukaryotes. Correct regulation of apoptosis is critical for normal development and the prevention of diseases, such as cancer. Genetic analysis of invertebrate model organisms has proven invaluable for the identification and study of key molecules involved in apoptosis. In Drosophila, the proteins Reaper (Rpr), Head involution defective (Hid) and Grim induce cell death in a caspase dependent manner by inhibiting the anti-apoptotic function of diap1.

Methods: To further elucidate the molecular mechanisms underlying the control of apoptosis, we conducted a dominant modifier screen for genes that could suppress the strong eye ablation phenotype caused by expressing hid under the control of an eye-specific promoter.

Results: As previously reported, we identified several loss of function mutants in components of the EGFR/Ras/MAPK pathway that could dominantly suppress hid-induced apoptosis. These mutants proved to be alleles of either sprouty or gap1, two negative regulators of the RTK/Ras1 signaling. Here we report the identification and characterization of the first gain of function mutation in the Drosophila RAS1 gene.

Conclusions: Taken together, these findings provide a molecular paradigm for the anti-apoptotic function of ras oncogenes.
Golgi-bound Rab34 is a novel member of the secretory pathways
Authors: Goldenberg Neil M. , Grinstein Sergio , Silverman Mel
Published: May 2017

Background: Golgi-localized Rab34 has been implicated in repositioning of lysosomes and activation of macropinocytosis.

Methods: Using HeLa cells we undertook a detailed investigation of Rab34 involvement in intracellular vesicle transport.

Results: Immunoelectron microscopy and immunocytochemistry confirmed that Rab34 is localized to the Golgi stack and that active Rab34 shifts lysosomes to the cell centre. Contrary to a previous report, we found that Rab34 is not concentrated at membrane ruffles and is not involved in macropinocytosis. Also, Rab34 induced repositioning of lysosomes does not affect transport of the mannose 6-phosphate receptor to endosomes. Most strikingly, HeLa cells depleted of Rab34 by transfection with dominant-negative Rab34, or following RNA interference, failed to transport the temperature-sensitive Vesicular Stomatitis Virus G-protein fused to GFP (VSVG-GFP) from the Golgi to the plasma membrane. Transfection with mouse Rab34 rescued this defect. Using endogenous MHC class I (MHC) as a marker, an endoglycosidase H resistance assay showed that ER to medial Golgi traffic remains intact in knock-down cells indicating that Rab34 specifically functions in post-Golgi transport. Further, brefeldin A treatment revealed that Rab34 acts at the Golgi, not the trans-Golgi network.

Conclusion: Collectively, these results define Rab34 as a novel member of the secretory pathway acting at the Golgi.
Relative value of plasma nitrotyrosine for predicting mortality in patients with coronary artery diseases
Authors: Heslop C L , Frohlich J J , Hill J S
Published: May 2017

Background: Reactive oxygen species (ROS) mediate the signalling of chief inflammatory pathways throughout all stages of atherosclerosis from endothelial dysfunction to plaque rupture. Activated leukocytes within the atherosclerotic lesion produce ROS, causing local and systemic oxidative injury; however, contributions of ROS production to the clinical features atherosclerosis have not yet been clearly established. Markers of oxidative stress include nitrotyrosine (N-tyr), a post-translational modification generated by reactive nitrogen species. N-tyr is enriched in atherosclerotic lesions, where it activates interstitial metalloproteases, which destabilize the lesion and induce plaque rupture. Recent findings associate circulating N-tyr levels with CAD pathogenesis: N-tyr levels are elevated in patients with established CAD, increased by risk factors associated with atherosclerosis, and reduced by statin therapy. The value circulating N-tyr may have for predicting outcome in CAD patients has not yet been determined.

Study Design: We tested the hypothesis that elevated N-tyr predicts mortality in patients with coronary artery disease. Plasma levels of N-tyr were measured using an enzyme-linked immunoassay (Hycult) in a cohort of 619 patients with angiographic evidence of coronary artery disease. After a mean follow-up time of 8.5 years, cases of all-cause mortality (145 cases) and cardiovascular mortality (76 cases) were collected using BC Vital Statistics Agency. The relative value of plasma N-tyr for prediction of mortality was determined using Cox proportional hazards model with adjustment for the following covariates: age, sex, smoking status, hypertension, BMI, LDL-cholesterol, total:HDL-cholesterol, plasma c-reactive protein, personal or known family history of CAD, and reported use of lipid-lowering or antioxidant therapies.

Interpretation: Patients whose plasma N-tyr levels were above the cohort median (71.75 nmol/L) had an increased risk of mortality, however this increased risk did not reach conventional statistical significance after covariate adjustment [HR(CI):1.39(0.96-2.01) p=0.07]. No significant association was observed between N-tyr levels and risk of cardiovascular mortality. While this investigation did not reveal a strong association between elevated N-tyr levels and cardiovascular mortality, the trend for increased risk of all-cause mortality indicates that this marker of oxidative stress could be used to identify patients for whom oxidative processes contribute significantly to disease pathogenesis. Further studies are warranted to establish the clinical value of N-tyr and other oxidative stress biomarkers, with the ultimate goal of improving patient risk assessment, and monitoring primary and secondary cardiovascular risk-reduction strategies.
High affinity IL-2 receptor (CD25) expression among Chronic Lymphocytic leukemia (CLL) patients is independent of mutational status and ZAP-70 positivitys
Authors: Howell J M , Luider J , Wong H , Perrizolo M , Demetrick D , Auer I , Mansoor A
Published: May 2017

Background: Recent studies have suggested promising roles for immunotherapy through CD40 ligand /IL-2 signaling pathway in CLL patients. Differential expression of the IL-2 receptor (IL-2 R) has been reported in CLL and other B-cell malignancies. Because CLL is divided into two distinct prognostic groups (based on the level of somatic hypermutation or alternatively on the presence or absence of ZAP-70), it is important to determine the correlation of IL-2 R expression with mutational status and/or ZAP-70 positivity in CLL for better patient group stratification in clinical trials.

Methods: In this study, 132 pts (82 M/50F; M: F 1.6) with an age range of 33-91 yrs (median 66 yrs) were included. Of these, 67/132 (51%) were found to be CD25+, 44/132 (33%) CD25- and 16% were CD25 dim (not further analyzed). In terms of ZAP positivity, 19/132 (14%) pts were ZAP-70+ and 113 (86%) were ZAP-70-.

Results: Mutational data (n=93) revealed 60/93 (65%) patients with SHM and 33/ 93 (35%) without. Correlation between ZAP-70+ and absence of SHM was highly significant (p< 0.0001), however, no statistically significant correlation was noted between CD25 expression and SHM (p= 0.331) or ZAP positivity (p= 0.785).

Conclusions: This data suggests that IL-2 R expression, although noted among a significant proportion of patients with B-CLL, is independent of somatic hypermutation or ZAP-70 expression. This observation will be important in evaluation of clinical efficacy of immunotherapy among CLL patients, and points to the existence of another mechanism for the presence of IL-2 R in these patients.

Abbreviations: B-CLL (B-cell Chronic Lymphocytic Leukemia), SHM (Somatic Hypermutation)
Spatial localization of unknown proteins in the endoplasmic reticulum predicts functions
Authors: Jain Michael D. , Nagaya Hisao , Gilchrist Annalyn , Cygler Miroslaw , Bergeron John J.M.
Published: May 2017

Protein synthesis, folding and degradation functions are spatially segregated in the endoplasmic reticulum (ER) with respect to the membrane and the ribosome (rough and smooth ER). Interrogation of a proteomics resource characterizing rough and smooth ER membranes subfractionated into cytosolic, membrane, and soluble fractions gives a spatial map of known proteins involved in ER function. The spatial localization of 224 identified unknown proteins in the ER is predicted to give insight into their function. Here we provide evidence that the proteomics resource accurately predicts the function of new proteins involved in protein synthesis (nudilin), protein translocation across the ER membrane (nicalin), co-translational protein folding (stexin), and distal protein folding in the lumen of the ER (erlin-1, TMX2). Proteomics provides the spatial localization of proteins and can be used to accurately predict protein function.
Modulation of NMDA receptors by prion proteins
Authors: Khosravani Houman , Zhang Yunfeng , Tsutsui Shigeki , Hameed Shahid , Hamid Jawed , Altier Christophe , Jirik Frank R. , Zamponi Gerald W.
Published: May 2017

Background: The precise physiological function of endogenous cellular prion protein (PrPC) remains unclear. It has been shown that PrP-null mice exhibit reduced LTP and greater susceptability to seizure mortality in several in vivo (e.g. kainic acid) models of epilepsy. In addition, PrP-null mice exhibit greater exctitotoxic cell death in response to kainic acid exposure. Methods: In our study we investigated the synaptic properties of WT and PrP-null mice.

Results: Recordings in the CA1 layer of adult hippocampal slices showed that PrP-null mice exhibit a reduced threshold to evoked responses and no difference in paired-pulse facilitation relative to WT animals. In addition, greater excitability was observed in PrP-null slices in response to zero-Mg2+ induced seizure-like events. Recordings from mature hippocampal cultures showed slightly altered AMPA and GABAA miniature synaptic currents. NMDA mEPSCs were observed to be increased in amplitude and significantly prolonged in decay time. NMDA-evokved currents also exhibited markedly prolonged deactivation kinetics. This effect on evoked NMDA currents was reproduced in WT neurons by PrP-RNAi transfection, and eliminated by PrPC transfection into PrP-null neurons.

Conclusions: These data suggest enhanced NMDA activity in PrP-null neurons. Consistent with this finding, in vitro and in vivo excitotoxicity assays demonstrated increased neuronal cell death in PrP-null cultures and animals upon transient exposure to NMDA. The prolonged deactivation kinetics were most consistent with functional activity/augmentation of NR2D NMDA receptor subunits, and PrP coimmunoprecipiated with NR2D NMDA receptor subunits. This enhanced NMDA receptor function was paralleleld by increased excitotoxicy in Prp-null mice. Our findings demonstrate a novel functional role for PrP as a modulator of synaptic NMDA currents and attributes a neuroprotective function to PrP.
A genome-wide linkage scan for familial partial lipodystrophy susceptibility genes in a German kindreds
Authors: Lanktree M. , Robinson J. , Creider J. , Cao H. , Carter D. , Horsch D. , Hegele R.
Published: May 2017

Background: In Dunnigan-type familial partial lipodystrophy (FPLD) patients are born with normal fat distribution, but subcutaneous fat from extremities and gluteal regions are lost during puberty. The abnormal fat distribution leads to the development of metabolic syndrome (MetS), a cluster of phenotypes including hyperglycemia, dyslipidemia, hypertension, and visceral obesity. The study of FPLD as a monogenic model of MetS may uncover genetic risk factors of the common MetS which affects ~30% of adult North Americans. Two molecular forms of FPLD have been identified including FPLD2, resulting from heterozygous mutations in the LMNA gene, and FPLD3, resulting from both heterozygous dominant negative and haploinsufficiency mutations in the PPARG gene. However, many patients with clinically diagnosed FPLD have no mutation in either LMNA or PPARG, suggesting the involvement of additional genes in FPLD etiology.

Methods: Here, we report the results of an Affymetrix 10K GeneChip microarray genome-wide linkage analysis study of a German kindred displaying the FPLD phenotype and no known lipodystrophy-causing mutations.

Results: The investigation identified three chromosomal loci, namely 1q, 3p, and 9q, with non-parametric logarithm of odds (NPL) scores >2.7. While not meeting the criteria for genome-wide significance, it is interesting to note that the 1q and 3p peaks contain the LMNA and PPARG genes respectively.

Conclusions: Three possible conclusions can be drawn from these results: 1) the peaks identified are spurious findings, 2) additional genes physically close to LMNA, PPARG, or within 9q, are involved in FPLD etiology, or 3) alternative disease causing mechanisms not identified by standard exon sequencing approaches, such as promoter mutations, alternative splicing, or epigenetics, are also responsible for FPLD.
Modulating hedgehog and beta-catenin signaling in osteoarthritiss
Authors: Lin A. C. , Alman B. A.
Published: May 2017

Osteoarthritis (OA) is a common degenerative disease of the joints, characterized by cartilage deterioration and subchondral bone changes. Interestingly, these changes to the joint phenotype in OA are influenced by signalling pathways that are normal to limb development. For example, chondrocytes found in the articular cartilage of joints are under influence of beta-catenin signalling, chondrocytes of growth plate cartilage are regulated by hedgehog signalling, and bone formation involves both beta-catenin and hedgehog signalling. We hypothesize that modulating these signalling pathways in OA can alter the joint phenotype, thereby reversing the cartilage and bone pathologies and improving articular cartilage regeneration. We aim to test our hypothesis using human OA samples, murine OA models, transgenic mice dysregulated for hedgehog and beta-catenin signalling, and limb explants cultures. The data generated will not only elucidate a fundamental understanding of cartilage fate regulation at the joint, but will also suggest novel treatments of osteoarthritis.
Determinating the role of the E3 Ubiquitin Ligase Ariadne 2 in mammalian systemss
Authors: Lin A. E. , Wakeham A. , You-Ten A. , Wood G. , Mak T. W.
Published: May 2017

Ubiquitination is a eukaryotic process of selective proteolysis, where a highly conserved ubiquitin protein is selectively added as a chain to the targeted to a protein for degradation. In recent years, the process of ubiquitination has been shown to be a critical mechanism that can affect essential signalling pathways, including apoptosis, cell cycle arrest and induction of the inflammatory response. Thus, alterations in the ubiquitination process can alter signalling pathways pivotal to numerous disease pathologies. This is clearly demonstrated in perturbations of ubiquitination in the NFκB giving rise to cancer and other immunological disease processes. To gain insight into pathways that require regulation by ubiquitination, our lab has directed focus on the highly conserved E3 ligase, Ariadne 2. Ariadne 2 is characterized as a putative RING finger E3 ligase and is part of the family of highly conserved RBR (RING-B-Box-RING) superfamily. The role of Ariadne 2 has been well studied in Drosophila melanogaster, however, little is known of the function of Ariadne 2 in mammalian systems. Therefore, the main objectives of the project are as follows: To determine the biological role of Ariadne 2, the role of Ariadne 2 in development and differentiation, and the consequences of in vivo loss of Ariadne 2 expression. We are currently investigating the role of Ariadne 2 as an E3 ligase and its involvement in the immune response. To date, we have shown that Ariadne 2 is ubiquitously expressed, especially in the brain, heart, spleen and thymus. For in vivo loss of function analysis, mice were generated by homologous recombination to be deficient for Ariadne 2. These deficient mice die prematurely soon after birth, suggesting a critical role for Ariadne 2 in development and survival. We are currently focusing on the role of Ariadne 2 in development and it’s role in immune pathologies, in particular, spontaneous autoimmunity, using both in vitro studies and in vivo models.
Attention and grasping in Parkinson's disease: Effects of treatment and disease stages
Authors: Lu Cathy , Suchowersky Oksana , Kiss Zelma , Haffenden Angela M
Published: May 2017

Objective: To compare the attentional resources devoted to reach-to-grasp movements at different stages of Parkinson’s disease (PD), on and off treatment, relative to intact controls.

Background: Reach-to-grasp movements are a critical component of activities of daily living. The grasping movements of patients with PD are characterized by a reliance on cues and visual feedback, not seen in the very automatic movements of intact controls (Azulay et al, 2006). PD patients appear to devote significant attentional resources to their movements; dual-task performance is a well-known area of difficulty for PD patients. To date, the role of attention in everyday reach-to-grasp movements has not been examined, though the implications for performance of activities of daily living are clearly considerable.

Methods: The performance of three patient groups [de novo (n=11); moderate (n=24); and surgical (STN DBS; n=14)] was compared with age matched controls (n=24) on a dual task paradigm involving grasping and a concurrent cognitive task designed to consume attention. Attentional resources were measured with standardized tests. Participants reached to grasp functional objects with handles (e.g. a comb). Handles were turned away from participants; an appropriate grasp was scored if they successfully picked up the object by the handle. Between and within group comparisons were made using ANOVA and t-tests.

Results: The control group and the de novo group not yet on medication displayed strong evidence of automaticity in their movements; when performing a challenging spatial imagery task, they made the same number of appropriate grasps as when they picked up the objects without a concurrent task. In contrast, for the moderate and the surgical groups, performing the concurrent task resulted in fewer appropriate grasps, and there was no improvement while on treatment (medication and stimulation, respectively). Only the surgical group showed decreased divided attention on standardized measures (>-0.7 SD below their normative group).

Conclusions: Grasping appears to shift from an automatic to an attention demanding process by the moderate stages of PD. This may be a coping mechanism designed to safely adapt to reduced motor function, or it may reflect pathology in the mechanisms underlying grasping movements.

References:

Azulay JP, Mesure S, and Blin O. 2006. J Neurol Sci, 248(1-2): 192-195.
Memory from one-trial training is resistant to extinction in Lymnaea Stagnaliss
Authors: Murias Kara , Amarell Martin , Lukowiak Ken
Published: May 2017

Background: Memories that follow a traumatic event or extreme stress have been shown in some cases, to be particularly resistant to therapies meant to reduce their impact on patients. Two methods shown to decrease memories in laboratory tests are disruption after reactivation and extinction training. Newly formed memories undergo a period of stabilization, during which they are susceptible to amnesia treatments. Over a period of time memories become stabilized and can no longer be disrupted. However memories that are retrieved are returned to a labile state that must undergo a process of ‘reconsolidation’. Also, many memories can be occluded by ‘extinction training’, which consists of withholding the training stimulus in the training environment resulting in a new memory that overshadows the original training.

Methods and Results: Using the Lymnaea stagnalis model system we show that memories following an extreme aversive stimulus demonstrate resistance to manipulation by these methods. Lymnaea stagnalis are fresh-water pond snails that can breathe either cutaneously or aerially through an orifice (pneumostome). Snails can form a long-term memory (LTM) to suppress pneumostome opening after operant conditioning consisting of either multiple sessions of repeated tactile stimulation to the orifice area each time the snail attempts to open its pneumostome or a single applications of 25mM KCl stimulus contingent with pneumostome opening (one-trial training; 1TT). The LTM formed following one-trial training has many of the same characteristics as memory formed following repetitive tactile training. Specifically, both are dependent on new mRNA synthesis in the circuit that controls aerial respiration and both can be blocked by cooling immediately after training. However, we show that memories in Lymnaea that form after a single, highly aversive stimulus, unlike LTM after repetitive training, aren’t disrupted after reactivation. We also attempted to extinguish the 1TT memory by placing the snails in the training beaker and not applying the KCl stimulus when they opened their pneumostome. When repetitive training was employed, extinction sessions such as these resulted in naïve levels of aerial respiration i.e. occlusion of the operantly trained memory.

Conclusions: Therefore, memory after 1TT is more resistant to suppression by extinction training than memories formed after less aversive stimuli. Further research will attempt to determine the cellular mechanism that causes the memory to be particularly resilient.
Intestinal microbiota balance modulates host susceptibility to infection with enteric pathogenss
Authors: Sekirov I , Tam N , Robertson M , Lupp C , Finlay B
Published: May 2017

Background: During our lifetimes we develop a very complex set of interactions with the multitude of microorganisms colonizing our bodies. In the gastrointestinal system, the microbiota is highly important for morphological development, nutrition, and protection against infectious diseases. The gastrointestinal pathogens, enterohemorrhagic and enteropathogenic Escherichia coli (EHEC and EPEC) and Salmonella enterica serovar Typhimurium (ST) are food-borne pathogens that cause much morbidity and mortality worldwide. Citrobacter rodentium (Cr) is a mouse pathogen that is used in small animal models to mimic EHEC and EPEC infections.

Methods: We began to characterize the contribution of intestinal microbiota to the progression of these infections. Two main phyla comprise the majority of mouse intestinal microbiota: Bacteroidetes and Firmicutes. Bacteria from a number of additional phyla are also present in smaller numbers; among them γ-Proteobacteria class, belonging to Proteobacteria phylum, is note-worthy as this class harbours many intestinal pathogens, such as ST and Cr. The mouse intestinal microbiota was perturbed using tetracycline (Tet) and streptomycin (Sm) to increase the proportion of Bacteroidetes in the colonic microbiota, and using vancomycin (Vanc) to create a predominance of Firmicutes. The mice with this perturbed microbiota were infected with ST to investigate the resultant pathology and virulence characteristics, and any additional shifts in microbiota as a result of infection.

Results: Treatment of mice with Sm and Vanc was found to decrease the resistance of mice to colonization with ST, while Tet-treated mice exhibited unchanged colonization resistance. Treatment of mice with gradually increasing doses of Sm, which gradually augmented the proportion of CFB bacteria in the microbiota, resulted in progressively increasing colonization of mice by ST, as well as a step-wise increase in the ST-induced typhlitis, associated with higher levels of inflammatory markers IL-6 and KC. The increasing levels of ST colonization following both Sm and Vanc treatment were associated with an increase in the proportion of γ-Proteobacteria in the cecal and colonic microbiota, as well as a decrease in the total bacterial numbers in both organs.

Conclusions: It is evident that the intestinal microbiota plays a significant role in the host’s response to infection with enteric pathogens, and its composition and numbers are also affected by the offending bacteria. Elucidation of the details regarding the contribution of the microbiota to infectious disease progression will offer novel targets for the future design of superior prevention and treatment methods.
The Dynactome-investigating dynamic network motifs of kinasess
Authors: So Jonathan , Elder Kelly , Colwill Karen , Linding Rune , Pawson Tony
Published: May 2017

Network motifs of kinases phosphorylating other kinases represent a unique control system for cellular functions. Recently, we described the bioinformatics tool NetworKIN (Linding et al, Cell in press) which accurately predicts kinase-substrate pairs. With these predicted feedback and feed-forward motifs of kinases, we characterize their effect through over-expression and monitoring of the phosphorylation of downstream signalling targets, such as MAP kinases. To understand the behaviour of this system in signal integration and cellular decision-making, we stimulate cells over-expressing a kinase with orthogonal signals, such as apoptosis promoting vs. growth-inducing cytokines, allowing for a more comprehensive coverage of signalling space (Janes et al., Science 2005). We present some feedback and feed-forward motifs found in the kinase-kinase network, and describe efforts to characterize dynamic phosphorylation sites in the context of orthogonal signals.