Decreased humoral immunity to mumps in young adults immunized with MMR vaccine in childhood.

In the past decade, multiple mumps outbreaks have occurred in the United States, primarily in close-contact, high-density settings such as colleges, with a high attack rate among young adults, many of whom had the recommended 2 doses of mumps-measles-rubella (MMR) vaccine. Waning humoral immunity and the circulation of divergent wild-type mumps strains have been proposed as contributing factors to mumps resurgence. Blood samples from 71 healthy 18- to 23-year-old college students living in a non-outbreak area were assayed for antibodies and memory B cells (MBCs) to mumps, measles, and rubella. Seroprevalence rates of mumps, measles, and rubella determined by IgG enzyme-linked immunosorbent assay (ELISA) were 93, 93, and 100%, respectively. The index standard ratio indicated that the concentration of IgG was significantly lower for mumps than rubella. High IgG avidity to mumps Enders strain was detected in sera of 59/71 participants who had sufficient IgG levels. The frequency of circulating mumps-specific MBCs was 5 to 10 times lower than measles and rubella, and 10% of the participants had no detectable MBCs to mumps. Geometric mean neutralizing antibody titers (GMTs) by plaque reduction neutralization to the predominant circulating wild-type mumps strain (genotype G) were 6-fold lower than the GMTs against the Jeryl Lynn vaccine strain (genotype A). The majority of the participants (80%) received their second MMR vaccine ≥10 years prior to study participation. Additional efforts are needed to fully characterize B and T cell immune responses to mumps vaccine and to develop strategies to improve the quality and durability of vaccine-induced immunity.

Blastic plasmacytoid dendritic cell neoplasm presenting as violaceous forehead plaque.

A 72-year-old man with a history of squamous cell carcinoma presented to the Portland VA with forehead discoloration. He was initially diagnosed with actinic damage and prescribed topical treatment. However, he returned to clinic months later with a large, violaceous forehead plaque. Upon biopsy, he was diagnosed with blastic plasmacytoid dendritic cell neoplasm (BPDCN), a rare hematological malignancy. This case report illustrates the importance of keeping BPDCN in the differential diagnosis for ecchymotic plaques that fail to respond to first line therapy.

Bioengineered functional brain-like cortical tissue.

The brain remains one of the most important but least understood tissues in our body, in part because of its complexity as well as the limitations associated with in vivo studies. Although simpler tissues have yielded to the emerging tools for in vitro 3D tissue cultures, functional brain-like tissues have not. We report the construction of complex functional 3D brain-like cortical tissue, maintained for months in vitro, formed from primary cortical neurons in modular 3D compartmentalized architectures with electrophysiological function. We show that, on injury, this brain-like tissue responds in vitro with biochemical and electrophysiological outcomes that mimic observations in vivo. This modular 3D brain-like tissue is capable of real-time nondestructive assessments, offering previously unidentified directions for studies of brain homeostasis and injury.

The Frequency and Utility of Drug Cessation Trials in Older Adults With Chronic Eczematous Dermatitis of Unknown Etiology: A Retrospective Cohort Study.

Background: Eczematous dermatitis is a major cause of recalcitrant pruritic eruptions in older adults. Although some medications have been implicated, there are limited data demonstrating the utility of medication changes. Objective: To investigate the utility and possible harms of drug cessation trials (DCTs) in chronic eczematous eruptions in the aging (CEEA). Methods: This is a retrospective cohort study utilizing electronic health records of DCTs in adults older than 65 years with CEEA. Results: We identified 646 patients >65 years with new onset eczematous eruptions, 89 (14%) of whom had no identifiable etiology. In this cohort, 35 patients underwent a total of 40 DCTs. Although there was mention of improvement in 17.5% (7/40), all patients sought tertiary care for their persistent rash. Negative outcomes occurred in 45% (18/40), all of which were due to exacerbation of a comorbidity that the medication was prescribed to treat. Conclusion: Our experience suggests that patients with CEEA undergo DCTs that do not improve their dermatitis and can lead to dangerous worsening of underlying conditions. Further study of the etiology of CEEA is needed.

Genotypic investigation of a rotavirus cluster at a quaternary-care pediatric hospital.

Rotavirus (RV) was a common healthcare-associated infection prior to the introduction of the RV vaccine. Following widespread RV vaccination, healthcare-associated rotavirus cases are rare. We describe an investigation of a cluster of rotavirus infections in a pediatric hospital in which an uncommon genotype not typically circulating in the United States was detected.

3D in vitro modeling of the central nervous system.

There are currently more than 600 diseases characterized as affecting the central nervous system (CNS) which inflict neural damage. Unfortunately, few of these conditions have effective treatments available. Although significant efforts have been put into developing new therapeutics, drugs which were promising in the developmental phase have high attrition rates in late stage clinical trials. These failures could be circumvented if current 2D in vitro and in vivo models were improved. 3D, tissue-engineered in vitro systems can address this need and enhance clinical translation through two approaches: (1) bottom-up, and (2) top-down (developmental/regenerative) strategies to reproduce the structure and function of human tissues. Critical challenges remain including biomaterials capable of matching the mechanical properties and extracellular matrix (ECM) composition of neural tissues, compartmentalized scaffolds that support heterogeneous tissue architectures reflective of brain organization and structure, and robust functional assays for in vitro tissue validation. The unique design parameters defined by the complex physiology of the CNS for construction and validation of 3D in vitro neural systems are reviewed here.

The behavior of neuronal cells on tendon-derived collagen sheets as potential substrates for nerve regeneration.

Peripheral nervous system injuries result in a decreased quality of life, and generally require surgical intervention for repair. Currently, the gold standard of nerve autografting, based on the use of host tissue such as sensory nerves is suboptimal as it results in donor-site loss of function and requires a secondary surgery. Nerve guidance conduits fabricated from natural polymers such as collagen are a common alternative to bridge nerve defects. In the present work, tendon sections derived through a process named bioskiving were studied for their potential for use as a substrate to fabricate nerve guidance conduits. We show that cells such as rat Schwann cells adhere, proliferate, and align along the fibrous tendon substrate which has been shown to result in a more mature phenotype. Additionally we demonstrate that chick dorsal root ganglia explants cultured on the tendon grow to similar lengths compared to dorsal root ganglia cultured on collagen gels, but also grow in a more oriented manner on the tendon sections. These results show that tendon sections produced through bioskiving can support directional nerve growth and may be of use as a substrate for the fabrication of nerve guidance conduits.

Semi-automatic quantification of neurite fasciculation in high-density neurite images by the neurite directional distribution analysis (NDDA).

BACKGROUND: Bundling of neurite extensions occur during nerve development and regeneration. Understanding the factors that drive neurite bundling is important for designing biomaterials for nerve regeneration toward the innervation target and preventing nociceptive collateral sprouting. High-density neuron cultures including dorsal root ganglia explants are employed for in vitro screening of biomaterials designed to control directional outgrowth. Although some semi-automated image processing methods exist for quantification of neurite outgrowth, methods to quantify axonal fasciculation in terms of direction of neurite outgrowth are lacking. NEW METHOD: This work presents a semi-automated program to analyze micrographs of high-density neurites; the program aims to quantify axonal fasciculation by determining the orientational distribution function of the tangent vectors of the neurites and calculating its Fourier series coefficients ('c' values). RESULTS: We found that neurite directional distribution analysis (NDDA) of fasciculated neurites yielded 'c' values of ≥∼0.25 whereas branched outgrowth led to statistically significant lesser values of <∼0.2. The 'c' values correlated directly to the width of neurite bundles and indirectly to the number of branching points. COMPARISON WITH EXISTING METHODS: Information about the directional distribution of outgrowth is lost in simple counting methods or achieved laboriously through manual analysis. The NDDA supplements previous quantitative analyses of axonal bundling using a vector-based approach that captures new information about the directionality of outgrowth. CONCLUSION: The NDDA is a valuable addition to open source image processing tools available to biomedical researchers offering a robust, precise approach to quantification of imaged features important in tissue development, disease, and repair.

The career trajectories of health care professionals practicing with permanent disabilities.

PURPOSE: The authors sought to generate insights and hypotheses about the professional experiences of registered nurses and physicians with self-identified disabilities to inform local and national policy conversations on supporting a diverse health care workforce. METHOD: In 2009-2010, the authors conducted in-depth interviews in person and over the telephone with a sample of licensed registered nurses and physicians across the country who self-identified as having a permanent disability. They coded the interview transcripts to identify key themes across the participants' responses. RESULTS: The authors interviewed 10 registered nurses and 10 physicians. Five novel and consistent themes emerged from the data analysis: (1) Living and working with a physical/sensory disability narrows the career choices and trajectories of nurses and physicians, (2) nurses and physicians struggle with decisions regarding whether to disclose and discuss their disabilities at work, (3) nurses and physicians rarely seek legally guaranteed workplace accommodations, instead viewing patient safety as a personal responsibility, (4) interpersonal interactions often reflect the institutional climate and set the tone for how welcome nurses and physicians feel at work, and (5) reactions to workplace disability-related challenges run an emotional spectrum from anger and grief to resilience and optimism. CONCLUSIONS: The responses revealed several missed opportunities for supporting health care professionals with disabilities in the workplace. These findings should inform the continuing debate regarding what defines "reasonable accommodation" and how to create a workplace that is welcoming for nurses and physicians with disabilities.