Hyperexcitable Phenotypes in Induced Pluripotent Stem Cell-Derived Neurons From Patients With 15q11-q13 Duplication Syndrome, a Genetic Form of Autism.

BACKGROUND: Chromosome 15q11-q13 duplication syndrome (Dup15q) is a neurogenetic disorder caused by duplications of the maternal copy of this region. In addition to hypotonia, motor deficits, and language impairments, patients with Dup15q commonly meet the criteria for autism spectrum disorder and have a high prevalence of seizures. It is known from mouse models that synaptic impairments are a strong component of Dup15q pathophysiology; however, cellular phenotypes that relate to seizures are less clear. The development of patient-derived induced pluripotent stem cells provides a unique opportunity to study human neurons with the exact genetic disruptions that cause Dup15q. METHODS: Here, we explored electrophysiological phenotypes in induced pluripotent stem cell-derived neurons from 4 patients with Dup15q compared with 6 unaffected control subjects, 1 patient with a 15q11-q13 paternal duplication, and 3 patients with Angelman syndrome. RESULTS: We identified several properties of Dup15q neurons that could contribute to neuronal hyperexcitability and seizure susceptibility. Compared with control neurons, Dup15q neurons had increased excitatory synaptic event frequency and amplitude, increased density of dendritic protrusions, increased action potential firing, and decreased inhibitory synaptic transmission. Dup15q neurons also showed impairments in activity-dependent synaptic plasticity and homeostatic synaptic scaling. Finally, Dup15q neurons showed an increased frequency of spontaneous action potential firing compared with control neurons, in part due to disruption of KCNQ2 potassium channels. CONCLUSIONS: Together, these data point to multiple electrophysiological mechanisms of hyperexcitability that may provide new targets for the treatment of seizures and other phenotypes associated with Dup15q.

Abundance and localization of human UBE3A protein isoforms.

Loss of UBE3A expression, a gene regulated by genomic imprinting, causes Angelman syndrome (AS), a rare neurodevelopmental disorder. The UBE3A gene encodes an E3 ubiquitin ligase with three known protein isoforms in humans. Studies in mouse suggest that the human isoforms may have differences in localization and neuronal function. A recent case study reported mild AS phenotypes in individuals lacking one specific isoform. Here we have used CRISPR/Cas9 to generate isogenic human embryonic stem cells (hESCs) that lack the individual protein isoforms. We demonstrate that isoform 1 accounts for the majority of UBE3A protein in hESCs and neurons. We also show that UBE3A predominantly localizes to the cytoplasm in both wild type and isoform-null cells. Finally, we show that neurons lacking isoform 1 display a less severe electrophysiological AS phenotype.

Compartmental and Spatial Rule-Based Modeling with Virtual Cell.

In rule-based modeling, molecular interactions are systematically specified in the form of reaction rules that serve as generators of reactions. This provides a way to account for all the potential molecular complexes and interactions among multivalent or multistate molecules. Recently, we introduced rule-based modeling into the Virtual Cell (VCell) modeling framework, permitting graphical specification of rules and merger of networks generated automatically (using the BioNetGen modeling engine) with hand-specified reaction networks. VCell provides a number of ordinary differential equation and stochastic numerical solvers for single-compartment simulations of the kinetic systems derived from these networks, and agent-based network-free simulation of the rules. In this work, compartmental and spatial modeling of rule-based models has been implemented within VCell. To enable rule-based deterministic and stochastic spatial simulations and network-free agent-based compartmental simulations, the BioNetGen and NFSim engines were each modified to support compartments. In the new rule-based formalism, every reactant and product pattern and every reaction rule are assigned locations. We also introduce the rule-based concept of molecular anchors. This assures that any species that has a molecule anchored to a predefined compartment will remain in this compartment. Importantly, in addition to formulation of compartmental models, this now permits VCell users to seamlessly connect reaction networks derived from rules to explicit geometries to automatically generate a system of reaction-diffusion equations. These may then be simulated using either the VCell partial differential equations deterministic solvers or the Smoldyn stochastic simulator.

Variability of staffing and staff mix across acute care units in Alberta, Canada.

BACKGROUND: The health workforce has a crucial position in healthcare, and effective distribution of the workforce is one of the critical areas for healthcare improvement. This requires a proper understanding of the allocation of healthcare providers including staffing levels and staffing variability within a healthcare system. High variability may imply significant differences in outcomes and greater opportunity to better distribute staffing and improve patient outcomes. The objective of this study was to examine staffing variation across acute care units in a large and integrated healthcare system. METHODS: We used survey and administrative data on full time equivalencies of Registered Nurses, Licensed Practical Nurses, Health Care Aides, and allied health staff for 287 acute care units to examine staffing levels across multiple unit types. We used a subsample of 157 units in a more detailed analysis of staffing levels and staff distribution. RESULTS: Results from the full sample indicate that staffing levels, particularly for Registered Nurses, vary substantially across unit types. Subsample analyses showed that the highest variation in staffing levels occurred in rural units, which also had higher average staffing for licensed practical nurses and allied health staff. Rural units had fewer Health Care Aides than did other units. The majority of units were staffed with a combination of all three nursing providers, but the most common arrangement in rural units was staffing of Registered Nurses and Licensed Practical Nurses only. We also found that units with the highest number Registered Nurses also tended to have higher numbers of other staff, particularly allied health providers. CONCLUSIONS: We observed significant variation in staffing levels and mix in acute care units. Some of the differences might be attributable to differences in patient needs and unit types. However, we also observed high variability in units with similar services and patient populations. As other research has shown that staffing is linked to differences in patient outcomes, there is an important opportunity to improve staffing for greater efficiency and higher quality care.

Introduction of a team-based care model in a general medical unit.

BACKGROUND: Alberta Health Services is a provincial health authority responsible for healthcare for more than four million people. The organization recognized a need to change its care delivery model to make care more patient- and family-centred and use its health human resources more effectively by enhancing collaborative practice. A new care model including changes to how providers deliver care and skill mix changes to support the new processes was piloted on a medical unit in a large urban acute care hospital Evidence-based care processes were introduced, including an initial patient assessment and orientation, comfort rounds, bedside shift reports, patient whiteboards, Name Occupation Duty, rapid rounds, and team huddles. Small teams of nurses cared for a portion of patients on the unit. The model was intended to enhance safety and quality of care by allowing providers to work to full scope in a collaborative practice environment. METHODS: We evaluated the new model approximately one year after implementation using interviews with staff (n = 15), surveys of staff (n = 25 at baseline and at the final evaluation) and patients (n = 26 at baseline and 37 at the final evaluation), and administrative data pulled from organizational databases. RESULTS: Staff interviews revealed that overall, the new care processes and care teams worked quite well. Unit culture and collaboration were improved, as were role clarity, scope of practice, and patient care. Responses from staff surveys were also very positive, showing significant positive changes in most areas. Patient satisfaction surveys showed a few positive changes; scores overall were very high. Administrative data showed slight decreases in overall length of stay, 30-day readmissions, staff absenteeism, staff vacancies, and the overtime rate. We found no changes in unit length of stay, 30-day returns to emergency department, or nursing sensitive adverse events. CONCLUSIONS: Conclusions from the evaluation were positive, providing initial support for the idea of the collaborative practice model vision for adult medical units across Alberta. There were also a few positive effects on patient care suggesting that models such as this one could improve the organization's ability to deliver sustainable, high-quality, patient- and family-centred care without compromising quality.

Development of an interactive model for planning the care workforce for Alberta: case study.

INTRODUCTION: In common with other jurisdictions, Alberta faces challenges in ensuring a balance in health worker supply and demand. As the provider organization with province-wide responsibility, Alberta Health Services needed to develop a forecasting tool to inform its position on key workforce parameters, in the first instance focused on modeling the situation for Registered Nurses, Licensed Practical Nurses and health care aides. This case study describes the development of the model, highlighting the choices involved in model development. CASE DESCRIPTION: A workforce planning model was developed to test the effect of different assumptions (for instance about vacancy rates or retirement) and different policy choices (for example about the size of intakes into universities and colleges, different composition of the workforce). This case study describes the choices involved in designing the model. The workforce planning model was used as part of a consultation process and to develop six scenarios (based on different policy choices). DISCUSSION AND EVALUATION: The model outputs highlighted the problems with continuation of current workforce strategies and the impact of key policy choices on workforce parameters. CONCLUSIONS: Models which allow for transparency of the underlying assumptions, and the ability to assess the sensitivity of assumptions and the impact of policy choices are required for effective workforce planning.

Planning to meet the care need challenge in Alberta, Canada.

The Canadian province of Alberta faces challenges in ensuring an adequate supply of nurses to meet care needs. This paper describes the approach adopted by Alberta Health Services (the public health care provider in Alberta) to address this challenge. Planning was undertaken on the basis of care needs rather than starting from a particular professional perspective and highlighted that the needs could be met by Registered Nurses, Licensed Practical Nurses or Healthcare Aides. Six scenarios, representing different potential mixes of Registered Nurses, Licensed Practical Nurses and Healthcare Aides were identified and used as the basis of stakeholder consultations. The paper identifies the workforce outcomes and needs for the different scenarios and the outcomes of the workforce planning process.

The impact of gown-use requirement on hand hygiene compliance.

BACKGROUND: Hand hygiene compliance remains low, despite its effectiveness in preventing infections. Gowns are routinely used to reduce dissemination of organisms within hospitals. Use of gowns is time consuming and costly, and their effectiveness, compared with that of hand hygiene alone, is debated. Among the arguments supporting a gown-use requirement is the potential to boost awareness of infection control, leading to improved hand hygiene compliance. METHODS: Hand hygiene compliance was recorded in a 14-month crossover trial comparing compliance at 2 intensive care units during periods with and without a gown-use requirement. RESULTS: During 170 h of observation, 1619 hand hygiene opportunities were recorded. Compliance was 10% before care was given and 36% after care was given. Compliance with glove and gown use was 62% and 63%, respectively. After-care hand hygiene compliance for nurses, physicians, and therapists was 40%, 38%, and 22%, respectively. Compliance after patient contact, body fluid contact, and other in-room activity was 42%, 48%, and 22%, respectively. For periods with and without a gown-use requirement, overall after-care compliance (37% vs. 34%) and rates by personnel and activity type were similar. In the subgroup of patients on contact precautions, hand hygiene compliance during the period with a gown-use requirement versus the period without a gown-use requirement was 11% versus 10% (P=.85) before care was given and 45% versus 39% (P=.09) after care was given. In this subgroup, after adjustment for type of in-room activity, medical personnel, intensive care unit, and observer, the predicted after-care hand hygiene compliance during periods with and without a gown-use requirement was 48% versus 41% (P=.02). CONCLUSIONS: The hypothesis that a gown-use requirement might improve hand hygiene compliance in the intensive care unit could not be confirmed. In the subgroup of patients on contact precautions, improvement in hand hygiene compliance associated with the gown-use requirement was small and did not affect precare rates.

Impact of cytomegalovirus prophylaxis on rejection following orthotopic liver transplantation.

With improved cytomegalovirus (CMV) prophylaxis, CMV disease after liver transplantation has decreased dramatically, and patient and graft survival have improved. We examined the impact of CMV prophylaxis on biopsy proven rejection after orthotopic liver transplantation by analyzing data on 192 liver recipients over 5 years (1994-1999). Risk factors assessed for biopsy proven rejection including donor and recipient age, CMV serostatus; CMV prophylaxis; immunosuppression; bacteremia and blood product use were examined over a 2-year follow-up. Multivariate analysis of risk factors for rejection showed that bacteremia (HR 3.57, 95% CI 1.39-9.36, P=0.008), donor age (HR 1.20, 95% CI 1.06-1.36, per 10 year increase, P=0.004), and use of cyclosporine as initial immunosuppression compared to tacrolimus (HR 1.98, 95% CI 1.27-3.09, P=0.003) were associated with increased risk; ganciclovir prophylaxis for 3 months (HR 0.51, 95% CI 0.33 to 0.79, P=0.003) and recipient age (HR 0.78; 95% CI 0.63-0.96, for each 10 year increase, P=0.03) were associated with decreased risk. We conclude that, the use of CMV prophylaxis with ganciclovir significantly reduces the incidence of biopsy proven rejection in liver transplant recipients.

The clinical impact of ganciclovir prophylaxis on the occurrence of bacteremia in orthotopic liver transplant recipients.

BACKGROUND: Cytomegalovirus (CMV) infection or receipt of a CMV-seropositive donor liver has been shown to be an independent predictor of bacteremia in orthotopic liver transplant (OLT) recipients. However, prevention of CMV infection through use of intense CMV prophylaxis has not been examined to assess the impact on bacteremia in liver transplant recipients. METHODS: We analyzed the impact of CMV prophylaxis on rates of bacteremia by examining 192 consecutive OLT recipients during a 2-year follow-up period. RESULTS: There were 29 episodes of bacteremia. Univariate analysis of risk factors for bacteremia showed that invasive fungal disease, initial anti-lymphocyte immunosuppression, treatment for rejection, and use of solumedrol were significantly associated with increased risk. Receipt of >or=14 days of ganciclovir prophylaxis (hazard ratio [HR], 0.40; 95% CI [confidence interval], 0.18-0.87; P=.02), end-to-end biliary anastomosis, and receipt of <10 units of red blood cells (RBCs) were significantly associated with a decreased risk. Three-variable analysis controlling for end-to-end anastomosis and use of <10 units of RBCs, showed that use of >or=14 days of ganciclovir was still associated with a reduced risk of bacteremia (HR, 0.44; 95% CI, 0.20-0.98; P=.0437). CONCLUSIONS: Among factors associated with bacteremia, use of prophylactic ganciclovir is independently associated with a significant reduction of bacteremia in OLT recipients.