Engineered Protein-G variants for plug-and-play applications.

We have developed a portfolio of antibody-based modules that can be prefabricated as standalone units and snapped together in plug-and-play fashion to create uniquely powerful multifunctional assemblies. The basic building blocks are derived from multiple pairs of native and modified Fab scaffolds and protein G (PG) variants engineered by phage display to introduce high pair-wise specificity. The variety of possible Fab-PG pairings provides a highly orthogonal system that can be exploited to perform challenging cell biology operations in a straightforward manner. The simplest manifestation allows multiplexed antigen detection using PG variants fused to fluorescently labeled SNAP-tags. Moreover, Fabs can be readily attached to a PG-Fc dimer module which acts as the core unit to produce plug-and-play IgG-like assemblies, and the utility can be further expanded to produce bispecific analogs using the "knobs into holes" strategy. These core PG-Fc dimer modules can be made and stored in bulk to produce off-the-shelf customized IgG entities in minutes, not days or weeks by just adding a Fab with the desired antigen specificity. In another application, the bispecific modalities form the building block for fabricating potent Bispecific T-cell Engagers (BiTEs), demonstrating their efficacy in cancer cell-killing assays. Additionally, the system can be adapted to include commercial antibodies as building blocks, greatly increasing the target space. Crystal structure analysis reveals that a few strategically positioned interactions engender the specificity between the Fab-PG variant pairs, requiring minimal changes to match the scaffolds for different possible combinations. This plug-and-play platform offers a user-friendly and versatile approach to enhance the functionality of antibody-based reagents in cell biology research.

A Qualitative Analysis of Factors Influencing Critical Care Trial Enrollment Among Surrogates.

BACKGROUND: We sought to identify factors that influence surrogate decision makers' decisions to enroll patients into a critical care randomized controlled trial. METHODS: We conducted a qualitative study embedded within a randomized controlled trial testing the effect of a behavioral nudge intervention for surrogate decision makers on enrollment rate in a sham ventilatory weaning trial among patients with acute respiratory failure. Participants were adult surrogate decision makers of patients receiving mechanical ventilation for acute respiratory failure. The study was conducted in 10 ICUs across 2 urban hospitals within an academic medical center in Philadelphia, Pennsylvanaia, United States. Immediately following their trial enrollment decision, surrogate decision makers were asked to enter free-text responses about the factors that influenced their decision. Responses were analyzed using content analysis. RESULTS: Of the 90 (49%) participants who provided free-text responses, the mean age was 54.9 years (SD 14.3), 69 (79%) were Caucasian, and 48 (53%) were the spouse of the eligible patient. We identified 5 themes influencing enrollment decisions: (i) trial characteristics, (ii) patient clinical condition, (iii) decision making processes, (iv) altruism, and (v) enrollment attempt. Among surrogates who enrolled the patient in the trial (n = 40), the most commonly cited factors were helping future patients (n = 24, 60%) and following the patient's wishes (n = 11, 28%). In contrast, those who declined enrollment (n = 50) most commonly reported that the patient was too sick (n = 27, 54%) and that they feared complicating the patient's condition (n = 11, 22%). CONCLUSIONS: Surrogates who enroll patients into trials most often cite altruistic motivations, while those who decline enrollment are most often concerned with the severity of the patients' condition.

Valproate-induced fatal acute hyperammonaemia-related encephalopathy in late-onset ornithine transcarbamylase deficiency.

Ornithine transcarbamylase (OTC) deficiency is a genetic disorder of the urea cycle characterised by deficiency in the enzyme OTC, resulting in an accumulation of ammonia. Valproic acid (VPA), a commonly used medication in the treatment of neurologic and psychiatric conditions, has been known to cause episodes of acute hyperammonaemia in patients with OTC deficiency. We present the case of a 29-year-old man with a long history of non-specific psychiatric disorders, who suffered from a hyperammonaemic crisis following the administration of VPA, leading to the diagnosis of OTC deficiency. The patient's hospital course was complicated by progressive cerebral oedema, which resulted in worsening encephalopathy, seizures and death. We discuss the pathophysiology of hyperammonaemia in OTC deficiency, and various management strategies, including lactulose, levocarnitine, scavenger therapy and haemodialysis.

Baseline neuropsychological profiles in prion disease predict survival time.

OBJECTIVE: Few studies have captured the neuropsychological profile of sporadic Creutzfeldt-Jakob disease (sCJD) with neuropsychological testing, and little is known about cognitive predictors of survival. We characterized baseline neuropsychological performance in sCJD and investigated associations with survival. METHODS: sCJD participants who completed the MMSE (n = 118), 61 sCJD of whom also completed a neuropsychological battery at baseline, and 135 age-matched healthy controls, were included. Composite scores of global cognition, memory, executive functions, visuospatial, and language were derived. Cox proportional hazard models estimated survival time, controlling for age and education. Additional models adjusted for Barthel Index and PRNP codon 129 polymorphism. RESULTS: sCJD participants performed significantly worse than controls on all cognitive tasks and composites with most showing very large effect sizes. The three tests showing the largest group differences were delayed verbal recall (Hedges'g = 4.08, P < 0.0001), Stroop Inhibition (Hedges'g = 3.14, P < 0.0001), and Modified Trails (Hedges'g = 2.94, P < 0.0001). Memory (95%) and executive functioning (87%) composites were most commonly impaired. Poorer global (HR = 0.65, P < 0.0001), visuospatial (HR = 0.82, P < 0.0001), and memory (HR = 0.82, P = 0.01) composites predicted shorter survival. Visuospatial cognition remained a significant predictor even after adjusting for all other cognitive composites; each standard deviation decrease in visuospatial cognition was associated with an 18% higher chance of death (HR = 0.82, P < 0.003). Global (HR = 0.68, P = 0.03) and visuospatial (HR = 0.82, P = 0.001) composites remained significant predictors after controlling for Barthel Index and codon 129. INTERPRETATION: sCJD participants exhibit a broad range of cognitive impairments, with memory and executive functioning deficits in the vast majority. Neuropsychological assessment, particularly of visuospatial abilities, informs prognostication in sCJD.

A Randomized Controlled Trial of Behavioral Nudges to Improve Enrollment in Critical Care Trials.

Rationale: Low and slow patient enrollment remains a barrier to critical care randomized controlled trials (RCTs). Behavioral economic insights suggest that nudges may address some enrollment challenges.Objectives: To evaluate the efficacy of a novel preconsent survey consisting of nudges on critical care RCT enrollment.Methods: We conducted an RCT in 10 intensive care units (ICUs) among surrogate decision-makers (SDMs). The novel multicomponent behavioral nudge survey was administered immediately before soliciting SDMs' informed consent for their patients' participation in a sham trial of two mechanical ventilation weaning approaches in acute respiratory failure. The primary outcome was the enrollment rate for the sham trial. Secondary outcomes included undue and unjust inducements. We also explored SDM and patient predictors of enrollment using multivariate regression.Results: Among 182 SDMs, 93 were randomized to receive the intervention survey and 89 to receive standard informed consent. There was no statistically significant difference in enrollment rates between the intervention (29%) and standard consent (34%) groups (percentage difference, 5%; 95% confidence interval [CI], -9% to 18%; P = 0.50). There was no evidence of undue or unjust inducement. White SDMs were more likely to enroll the patient compared with non-white SDMs (odds ratio, 3.7; 95% CI, 1.1 to 12.2; P = 0.03). SDMs who perceived a higher risk of participation were less likely to enroll the patient (odds ratio, 0.57; 95% CI, 0.46 to 0.71; P < 0.001).Conclusions: A preconsent behavioral nudge survey among SDMs of patients with acute respiratory failure in the ICU did not increase enrollment rates for a sham RCT compared with standard informed consent procedures.Clinical trial registered with ClinicalTrials.gov (NCT03284359).

Update on stem cell technologies in congenital heart disease.

BACKGROUND: Congenital heart disease (CHD) continues to be among the most common birth defects, affecting an estimated 40 000 births annually in the United States. The most common complication of CHD is heart failure. With improved medical management and surgical outcomes, survival for complex congenital heart defects has dramatically improved, but consequentially there are more adults with CHD than children with CHD. Due to longer-term sequelae of CHD, surgical and medical treatment previously thought to be curative is now realized at best to be palliative, and there is a considerable burden of CHD-related heart failure. Stem cell therapy as an adjunct to current surgical and medical strategies is being explored in an effort to ameliorate CHD-related heart failure. This review aims to explore the current literature with regard to stem cell therapy for CHD as well as ongoing trials. METHODS: A MEDLINE (Ovid), MEDLINE (Pubmed), and clinicaltrials.gov search were performed using the medical subject headings congenital heart defects combined with hematopoietic stem cells, stem cell transplantation, mesenchymal stem cells (MSC), cell- or tissue-based therapy, or MSC transplantation. Articles must have been published after 2010. RESULTS: Twenty three articles and 9 ongoing trials met all inclusion criteria. CONCLUSIONS: Areas of interest include myocardiocyte regeneration, tissue graft development to minimize reoperations, and methods of stem cell delivery. While several small trials are showing promise, it is too soon to make definitive statements about the future of stem cell therapies in this field.

Electronic medical record in the simulation hospital: does it improve accuracy in charting vital signs, intake, and output?

Nursing care delivery has shifted in response to the introduction of electronic health records. Adequate education using computerized documentation heavily influences a nurse's ability to navigate and utilize electronic medical records. The risk for treatment error increases when a bedside nurse lacks the correct knowledge and skills regarding electronic medical record documentation. Prelicensure nursing education should introduce electronic medical record documentation and provide a method for feedback from instructors to ensure proper understanding and use of this technology. RN preceptors evaluated two groups of associate degree nursing students to determine if introduction of electronic medical record in the simulation hospital increased accuracy in documenting vital signs, intake, and output in the actual clinical setting. During simulation, the first group of students documented using traditional paper and pen; the second group used an academic electronic medical record. Preceptors evaluated each group during their clinical rotations at two local inpatient facilities. RN preceptors provided information by responding to a 10-question Likert scale survey regarding the use of student electronic medical record documentation during the 120-hour inpatient preceptor rotation. The implementation of the electronic medical record into the simulation hospital, although a complex undertaking, provided students a safe and supportive environment in which to practice using technology and receive feedback from faculty regarding accurate documentation.

A single blinded randomised controlled pilot trial of prism adaptation for improving self-care in stroke patients with neglect.

Prism adaptation has been shown to alleviate the symptoms of unilateral spatial neglect following stroke in single case and small group studies. The purposes of this single blinded pilot randomised controlled trial were to determine the feasibility of delivering prism adaptation treatment in a clinically valid sample and to assess its impact on self-care. Thirty seven right hemisphere stroke patients with unilateral spatial neglect were randomised into either prism adaptation (using 10 dioptre, 6 degree prisms) or sham treatment (using plain glasses) groups. Treatment was delivered each weekday for two weeks. Pointing accuracy, without vision of the finger, was recorded each day before treatment. Outcome was measured, by blinded assessors, four days and eight weeks after the end of treatment using the Catherine Bergego Scale (CBS) and the conventional neuropsychological tests from the Behavioural Inattention Test (BIT). Thirty four patients received treatment: 16 with prisms, 18 sham. Mean compliance was 99% and 97%, respectively. Over the treatment days only the prism treated group showed increased leftward bias in open loop pointing to targets on a touch screen. However, despite the group level changes in pointing behaviour no overall effect of the treatment on self-care or BIT were found.

Walking and wheelchair navigation in patients with left visual neglect.

Patients with neglect veer to one side when walking or driving a wheelchair, however there is a contradiction in the literature about the direction of this deviation. The study investigated the navigational trajectory of a sample of neglect patients of mixed mobility status in an ecological setting. Fifteen patients with left-sided neglect after right hemisphere stroke were recorded walking or driving a powered wheelchair along a stretch of corridor. Their position in the corridor and the number of collisions was recorded. The results showed that the patients' path was dependent on their mobility status: wheelchair patients with neglect consistently deviated to the left of the centre of the corridor and walking patients with neglect consistently deviated to the right. A further two ambulant patients with neglect were recorded both walking and using the wheelchair to determine whether the differences were task or patient dependent. These two patients also exhibited leftward deviation when driving the wheelchair, but a rightward deviation when walking. These results suggest that the direction of the deviation is task dependent. Further work will be required to identify what features of the two modes of navigation lead to this dissociation.

The effects and costs of intimate partner violence for work organizations.

This study examines the productivity-related effects and costs of intimate partner violence (IPV) on the workplace. Specifically, it explores whether IPV victims and nonvictims differ in the number of work hours missed due to absenteeism, tardiness, and work distraction and the costs for employers from these missed work hours. The research involved a Web-based survey of 823 male and 1,550 female employees in three midsized organizations. Employees who reported lifetime IPV victimization, but not current victimization, missed more hours of work because of absenteeism than did nonvictims. Current victims, but not lifetime victims, were more likely to be distracted at work than nonvictims. Organization costs due to absenteeism and tardiness were greater for lifetime victims than nonvictims; however, no difference in costs was found for current victims. Overall, we found that IPV has negative effects on organizations, but that the nature and cost of these effects vary by type of victimization.