Exploring Cell Differentiation Vs. Localization in Engineered Ligament-to-Bone Entheses

The anterior cruciate ligament (ACL) connects to bone via structurally complex insertions known as entheses that translate load from elastic ligament and stiff bone via gradients in organization, composition, and cell phenotype [1]. These gradients are not recreated in graft repair or engineered replacements, yielding limited repair options and high failure rates [2]. Previously, we developed a culture system that uses a tensile-compressive interface to guide ligament fibroblasts to develop early postnatal-like entheses by 6 weeks [3]; however, cells used were isolated from the entirety of the neonatal bovine ACL from bone to bone and likely contained multiple cell phenotypes and progenitor cells [3]. This study explored how ligament fibroblasts from ACL mid-substance and fibrochondrocytes from ACL entheses respond to mechanical cues in our system to assess if cells localize to specific tissue regions or remain mixed and differentiate in response to the local mechanical environment over 6 weeks. Confocal microscopy revealed at 0 weeks all regions begin unorganized with an even distribution of ligament (green) and enthesis (violet) cells for 50/50 ligament/enthesis co-culture (Fig 1). By 6 weeks, 50/50 co-culture resulted in early postnatal-like organization [1,3] with mixed cell distribution; however, ligament cells appear to undergo zonal morphological changes with elongated cells in the middle and larger rounded cells under the clamp. Zonal cell morphology, biochemical, and mechanical analysis of 100% ligament, 100% enthesis, and 50/50 co-culture are ongoing. References: [1] Lu+ 2013, [2] Patel+ 2018, [3] Brown+ 2022.https://scholarscompass.vcu.edu/uresposters/1420/thumbnail.jp

Waiting for shelter: Perspectives on a homeless shelter’s procedures

Research on homeless shelter implementation is limited. Some shelters have lengthy waitlists, which raises important questions about implications of waitlists for individuals with immediate shelter needs. This study used qualitative methods to understand the experiences of shelter seekers who were on a shelter waitlist (N = 59), including individuals who entered the shelter from the waitlist, and those removed from the shelter waitlist for procedural reasons. The average waitlist time was nearly 3 weeks, and 22.0% stayed at least one night on the street or another public place while on the waitlist. Responses to open‐ended questions regarding barriers and effectiveness of the shelter referral procedures revealed 4 themes: procedural challenges, procedural benefits, benefits of the temporary stay, and communication challenges. Further research is needed to inform shelter implementation on a larger scale in accordance with current community‐wide efforts to coordinate shelter services.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138221/1/jcop21896_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138221/2/jcop21896.pd

Psychosocial Measures and Outcomes Among Caregivers of Children With Tracheostomies: A Systematic Review.

OBJECTIVE: Children with tracheostomies have complex medical issues that require long-term technology dependence and continuous medical care at home. Parents of tracheostomy-dependent children often assume the majority of their child\u27s home care leading to a shift in family dynamics and a decrease in caregiver quality of life. This systematic review sought to identify instruments to measure caregiver psychosocial outcomes after their child\u27s tracheostomy and report on the findings. DATA SOURCES: A systematic review was performed using Medline, CINAHL, and EMBASE. REVIEW METHODS: Studies that evaluated psychosocial outcomes in caregivers of tracheostomy-dependent children were included. RESULTS: We screened a total of 1286 nonduplicate records to include a total of 12 studies assessing the psychosocial outcomes of parents of tracheostomy-dependent children. Fourteen instruments were identified. Caregivers reported lower quality of life when compared to other chronic caregiver groups. They experienced high degrees of stress, struggled to cope individually and as a family unit, and experienced decision regret and conflict. CONCLUSION: Findings from this review suggest a significant impact on caregiver psychosocial well-being, but few quantitative studies investigated this dynamic with measures validated in this caregiver population. This review demonstrates the need for longitudinal studies using validated tools to assess the long-term impacts and outcomes of caregivers of the tracheostomy-dependent child

A Three Monoclonal Antibody Combination Potently Neutralizes Multiple Botulinum Neurotoxin Serotype E Subtypes.

Human botulism is most commonly caused by botulinum neurotoxin (BoNT) serotypes A, B, and E. For this work, we sought to develop a human monoclonal antibody (mAb)-based antitoxin capable of binding and neutralizing multiple subtypes of BoNT/E. Libraries of yeast-displayed single chain Fv (scFv) antibodies were created from the heavy and light chain variable region genes of humans immunized with pentavalent-toxoid- and BoNT/E-binding scFv isolated by Fluorescence-Activated Cell Sorting (FACS). A total of 10 scFv were isolated that bound one or more BoNT/E subtypes with nanomolar-level equilibrium dissociation constants (KD). By diversifying the V-regions of the lead mAbs and selecting for cross-reactivity, we generated three scFv that bound all four BoNT/E subtypes tested at three non-overlapping epitopes. The scFvs were converted to IgG that had KD values for the different BoNT/E subtypes ranging from 9.7 nM to 2.28 pM. An equimolar combination of the three mAbs was able to potently neutralize BoNT/E1, BoNT/E3, and BoNT/E4 in a mouse neutralization assay. The mAbs have potential utility as therapeutics and as diagnostics capable of recognizing multiple BoNT/E subtypes. A derivative of the three-antibody combination (NTM-1633) is in pre-clinical development with an investigational new drug (IND) application filing expected in 2018

Reliability of Two Alternative Methods for the Standard Mid-thigh Isometric Pull

The purpose of this study was to determine the reliability of two new alternative portable methods for measuring maximal isometric force measures while performing the standard mid-thigh pull. One method, the bar grip method, required the use of the trunk and upper extremity muscles, while the second method, the pelvic belt method, did not. Both methods demonstrated good test-retest reliability via randomized repeated measures over 24-36 hours. Interestingly, the pelvic belt method generally demonstrated average maximal forces up to 65% higher than the bar method. There was a good relationship between both methods. These new alternative methods could provide strength coaches an option for a more efficient, cost-effective, portable means for the mid-thigh pull test

Fetal MRI in the Identification of a Fetal Ventral Wall Defect Spectrum

Objective  To ascertain if useful criteria for prenatal diagnosis of fetal ventral body wall defects (VBWDs) exists by reviewing published literature on diagnosis of VBWD as compared with our own diagnostic experience. Study Design  A comprehensive literature review of diagnostic criteria of fetal VBWD including pentalogy of Cantrell (POC), omphalocele, exstrophy, imperforate anus, spina bifida (OEIS), cloacal exstrophy, limb-body wall complex (LBWC), and body stalk anomaly was performed followed by a retrospective review of all fetal magnetic resonance imaging (MRI) examinations from our medical center over a 2-year period. Results  Classically, OEIS is omphalocele, bladder exstrophy, imperforate anus, and spina bifida. POC is defects of the supraumbilical abdomen, sternum, diaphragm, pericardium, and heart. LBWC is two of the following: exencephaly or enencephaly with facial clefts, thoracoschisis or abdominoschisis, and limb defects. Twenty-four cases of VBWD on MRI over a 24-month period were identified with seven cases involving defects of additional organ systems. Six of these seven cases demonstrated findings from two or more of the traditional diagnoses POC, OEIS, and LBWC making diagnosis and counseling difficult. Conclusion  There is a lack of consensus on useful diagnostic criteria within the published literature which is reflected in our own diagnostic experience and poses a challenge for accurate prenatal counseling

Seasonal variation in effects of herbivory on foliar nitrogen of a threatened conifer

Invasive herbivores can dramatically impact the nitrogen (N) economy of native hosts. In deciduous species, most N is stored in stem tissues, while in evergreen conifer species N is stored in needles, making them potentially more vulnerable to herbivory. In eastern forests of the USA, the long-lived, foundational conifer eastern hemlock (Tsuga canadensis) is under the threat of extirpation by the invasive hemlock woolly adelgid (HWA: Adelges tsugae). We assessed the impact of HWA infestation on the patterns of seasonal foliar N availability in hemlock planted in a deciduous forest understory. Over the course of a year, we sampled needles and twigs and measured N, carbon (C), C:N ratio, and total protein concentrations. Tissue sampling events were timed to coincide with key life-history transitions for HWA to determine the association between HWA development and feeding with these foliar nutrients. In uninfested trees, needle and twig N concentrations fluctuated across seasons, indicating the potential importance of N storage and remobilization for the N economy of eastern hemlock. Although N levels in HWA-infested trees also cycled annually, the degree to which N concentrations fluctuated seasonally in tissues was significantly affected by HWA feeding. These fluctuations exceeded N levels observed in control trees and coincided with HWA feeding. HWA feeding generally increased N concentrations but did not affect protein levels, suggesting that changes in N do not occur via adelgid-induced protein breakdown. Herbivore-induced mobilization of N to feeding sites and its rapid depletion may be a significant contributor to eastern hemlock mortality in US forests