Bridging the Gap: Comparison of Outpatient Clinic and Emergency Department Patients Undergoing Cholecystectomy.

INTRODUCTION: Literature shows failure of the outpatient clinic (OC) pathway after emergency department (ED) ultrasound diagnosis of symptomatic cholelithiasis (SC). We hypothesized SC to be more prevalent on final surgical pathology (FSP) in patients who successfully completed OC pathway. METHODS: This retrospective single-institution chart review compared OC and ED patients with right upper quadrant (RUQ) pain and cholelithiasis whom underwent cholecystectomy. Clinical evaluation was considered positive if RUQ pain >4 h, or + Murphy's sign. Ultrasound was positive if two of these three were present: sonographic Murphy's, wall thickness > 4 mm, or pericholecystic fluid. Results were compared with FSP. RESULTS: Six hundred-seven patients underwent cholecystectomy, 299 OC and 308 ED. OC was more likely to SC (23% versus 4.6%) (P < 0.0001) and ED acute cholecystitis (39.3% versus 4.7%). Chronic cholecystitis was the most common FSP in both OC (72%) and ED (56%) populations, of these, 73% of OC denied pain >4 h versus only 10% of ED (P < 0.001). Median time from evaluation to cholecystectomy was 14 d versus 14 h in the OC and ED respectively (P < 0.0001). CONCLUSIONS: While chronic cholecystitis was the most common FSP in both OC and ED, the majority of OC reported RUQ pain <4 h delineating these presentations. Duration of pain should be utilized as algorithm triage. We recommend patients with pain episode <4 h should complete OC algorithm with expedited cholecystectomy within 14 d.

Newborn Skin: Part I. Common Rashes and Skin Changes.

Rashes in the newborn period are common and most are benign. Infections should be suspected in newborns with pustules or vesicles, especially in those who are not well-appearing or have risk factors for congenital infection. Congenital cytomegalovirus infection can cause sensorineural hearing loss and neurodevelopmental delay. Skin manifestations of cytomegalovirus may include petechiae due to thrombocytopenia. The most common skin manifestations of early congenital syphilis are small, copper-red, maculopapular lesions located primarily on the hands and feet that peel and crust over three weeks. Erythema toxicum neonatorum and neonatal pustular melanosis are transient pustular rashes with characteristic appearance and distribution. Neonatal acne is self-limited, whereas infantile acne may benefit from treatment. Milia can be differentiated from neonatal acne by their presence at birth. Cutis marmorata and harlequin color change are transient vascular phenomena resulting from inappropriate or exaggerated dilation of capillaries and venules in response to stimuli.

Newborn Skin: Part II. Birthmarks.

Birthmarks in newborns can be classified as vascular, melanocytic or pigmented, or markers of underlying developmental abnormalities of the nervous system. A nevus simplex is a benign capillary malformation. Newborns with a nevus flammeus can be safely treated before one year of age with a pulsed dye laser to reduce the visibility of lesions. Infantile hemangiomas should be treated with systemic beta blockers if there is a risk of life-threatening complications, functional impairment, ulceration, underlying abnormalities, permanent scarring, or alteration of anatomic landmarks. Dermal melanocytosis is a benign finding that is easily recognized and does not warrant further evaluation. A solitary congenital melanocytic nevus that is less than 20 cm in diameter may be observed in primary care; children with larger or multiple nevi should be referred to pediatric dermatology due to the risk of melanoma. Newborns with skin markers of occult spinal dysraphism (other than a simple, solitary dimple) should have lumbar spine imaging using ultrasonography or magnetic resonance imaging.

Perforated Appendicitis in Children: Management, Microbiology, and Antibiotic Stewardship.

Although appendicitis has been described for more than 300 years, its optimal management remains a topic of active investigation. Acute appendicitis is the most common cause of peritonitis in children, and rates of perforated appendicitis are much higher in children than in adults. Increased risk for perforated appendicitis in children is related to a delay in diagnosis due to age, size, access to care, and more. Surgical options include immediate appendectomy versus nonoperative management with intravenous antibiotics ± a drainage procedure, with a subsequent interval appendectomy. Microbiota of perforated appendicitis in children most often includes Escherichia coli, Bacteroides fragilis, Streptococcus, and more. Even though the most common organisms are known, there is a large variety of practice when it comes to postoperative antibiotic management in these patients. Studies discuss the benefits of mono- versus dual or triple therapy without a particular consensus regarding what to use. This is reflected across differing practices at various institutions. In this review, we aim to explore the implications of perforated appendicitis in pediatrics, common organisms seen, antibiotic regimen coverage, and the implications of variations of practice. Resistance to commonly used broad-spectrum antibiotics is evolving, therefore minimization of care variability is needed for improved patient outcomes and proper antibiotic stewardship.

Pediatric Traumatic Lumbar Hernias and Associated Injuries: A Case Series.

OBJECTIVE: Traumatic lumbar hernias are a rare entity mostly seen with high-impact, blunt abdominal trauma. This injury occurs when there is disruption of the posterior musculature along with bony structures, allowing for herniation of abdominal contents. There are minimal cases of this entity reported in adults, but even fewer in the pediatric population. METHODS: We describe 3 cases of traumatic lumbar hernia at our institution as well as provide a review of the literature to elucidate the most common mechanisms, severity of injury, and associated injuries. RESULTS: Traumatic lumbar hernia is most commonly seen in restrained passengers involved in motor vehicle collisions. A majority of cases are diagnosed using computed tomography imaging and less frequently during primary surgical exploration. The most common associated injuries were mesenteric and bowel injuries, followed by spinal and chest trauma. Traumatic lumbar hernia often leads to prolonged hospital stays and increased need for posthospital rehabilitation because of associated traumatic comorbidities. CONCLUSIONS: Traumatic lumbar hernia is a rare entity in children, and early suspicion and identification of associated injuries is necessary in the management of these patients.

Despite Recovery from Necrotizing Enterocolitis Infants Retain a Hyperinflammatory Response to Injury.

Background: Necrotizing enterocolitis (NEC) is the leading gastrointestinal cause of death of premature neonates. NEC is associated with prematurity, a hyperinflammatory response, and dysregulation of intestinal barrier function. We hypothesize that patients with NEC will have, and continue to have after recovery, an increased hyperinflammatory intestinal response compared to those patients without NEC. Methods: Neonates with NEC, those that have recovered from NEC, and those without NEC undergoing intestinal resections had specimens collected and snap frozen or generated into enteroids. The enteroids were treated with 100ug/mL lipopolysaccharide (LPS) and subjected to 24 hr of hypoxia together, then compared with untreated controls. Expression of Tumor Necrosis Factor (TNF-α) and interleukin 8 (IL-8) were evaluated via RT-qPCR and ELISA to measure inflammatory response. ANOVA determined statistical significance (p<0.05). Results: There was no difference in inflammatory markers in recovered NEC tissue compared to non-NEC tissue on RTqPCR (p=0.701 TNF-α and 0.861 IL-8). However, recovered NEC enteroids demonstrate elevated levels of inflammatory markers after treatment compared to non-NEC enteroids after treatment on RTqPCR (p=0.0485 TNF-α, p=0.0057 IL-8) and ELISA (p=0.0354 TNF-α, p=0.0011 IL-8). Recovered NEC enteroids that underwent treatment demonstrated increased inflammatory markers compared to recovered NEC enteroids without treatment on RTqPCR (p=0.0045 TNF-α, p=0.0002 IL-8) and ELISA (p=0.034 TNF-α, p=0.0002 IL-8) suggesting a heightened inflammatory response to a second hit. Conclusion: Intestinal tissue resected from neonates with NEC has an elevated hyperinflammatory response compared to neonates recovered from NEC and neonates without NEC. Enteroids generated from patients that have recovered from NEC have a heightened inflammatory response in response to NEC inducing stimuli compared to controls. This tendency towards an increased hyperinflammatory state may be correlated with an infant's proclivity to develop NEC and demonstrates the significance of a second hit on this tissue creating a heightened inflammatory response. This could be correlated with the impact and trajectory of an illness post recovery from NEC.

Not all cholecystitis is created equal: Disparities contributing to ED presentation and failure of the outpatient algorithm.

BACKGROUND: The majority of final surgical pathology (FSP) from both emergency department (ED) and outpatient clinic (OC) patients is chronic cholecystitis. We aimed to differentiate these presentations and identify disparities associated with ED utilization and OC failure. METHODS: Retrospective chart review of single institution ED and OC cholecystectomies for cholelithiasis. Clinical presentation, FSP, demographics, and zip code poverty (ZCP) levels were evaluated. Data analysis by summary statistics, bivariate comparisons, and logistic regression. RESULTS: Of 299 OC and 308 ED patients, OC was more likely to be Caucasian (78% vs 46%, p < 0.0001) and insured (89% vs. 32%, p < 0.0001). 71.8% of OC with ZCP <10% had insurance versus only 32.5% in ZCP >20%. Uninsured ED OR was 13.1 (95% CI 8.7-22.9). CONCLUSION: Uninsured ED patients are vulnerable to fail the outpatient algorithm, especially when misdiagnosed by US. Clinical diagnosis of cholecystitis in this population should warrant offering of urgent cholecystectomy.

Response of the Glutathione (GSH) Antioxidant Defense System to Oxidative Injury in Necrotizing Enterocolitis.

Necrotizing enterocolitis (NEC) is a neonatal intestinal disease associated with oxidative stress. The targets of peroxidation and the role of the innate intestinal epithelial antioxidant defense system are ill-defined. We hypothesized that oxidative stress in NEC correlates with oxidized GSH redox potentials, lipid peroxidation, and a dysfunctional antioxidant system. Methods: Intestinal samples from infants +/- NEC were generated into enteroids and incubated with lipopolysaccharide (LPS) and hypoxia to induce experimental NEC. HPLC assayed GSH redox potentials. Lipid peroxidation was measured by flow cytometry. Immunoblotting measured glutathione peroxidase 4 (Gpx4) expression. Results: GSH redox potentials were more oxidized in NEC intestinal tissue and enteroids as compared to controls. Lipid radicals in NEC-induced enteroids were significantly increased. Human intestinal tissue with active NEC and treated enteroid cultures revealed decreased levels of Gpx4. Conclusions: The ability of neonatal intestine to mitigate radical accumulation plays a role in its capacity to overcome oxidative stress. Accumulation of lipid radicals is confirmed after treatment of enteroids with NEC-triggering stimuli. Decreased Gpx4 diminishes a cell's ability to effectively neutralize lipid radicals. When lipid peroxidation overwhelms antioxidant machinery, cellular death ensues. Identification of the mechanisms behind GSH-dependent enzyme dysfunction in NEC may provide insights into strategies for reversing radical damage.

Anecdotes Drive Attitudes, Data Drives Decisions: Optimizing the Emergency Department Workup Prior to Surgical Consultations.

PURPOSE: Emergency department (ED) wait times and ED length of stay (LOS) have a significant impact on patient morbidity and mortality and patient satisfaction. Consultation-to-decision time can contribute to increased wait times and LOS in the ED. Up to 40% of patients presenting to the ED require consultation from subspecialty services. We hypothesize that in surgical patients, completion of workup prior to consultation will decrease consultation-to-decision time, ED wait times, and LOS in the ED. METHODS: A retrospective review was conducted at a single site including all overnight general surgery consultations from the ED over 2-months. Data collected included wait times, LOS, and workup completed prior to consultation. Summary statistics were calculated and bivariate tests were performed using t-tests for continuous variables. RESULTS: Time to final surgical plan and LOS in ED were evaluated for 137 patients comparing "complete" and "incomplete" workups at time of consultation. It was considered a "complete" workup if labs and imaging were resulted prior to time of consult. If any baseline tests were not ordered prior to time of consult, it was considered an "incomplete" workup. Analysis demonstrated an average time of 4.9 and 2.5 hours for consultation-to-decision time for "incomplete" and "complete" workups respectively (p < 0.0001). For LOS in ED, there was an average of 11.4 and 7.9 hours for "incomplete" and "complete" workups respectively (p < 0.0001). CONCLUSIONS: There is a significant difference in consultation-to-decision time and LOS in the ED when consultation is performed following a complete versus incomplete workup for surgical patients independent of inherent wait times for testing to result and the need for additional testing requested from consulting services. Developing strategies to optimize workups from the ED prior to surgical consultation, including the development of care pathways, could significantly decrease patient wait times and LOS in the ED.

Examining the association between blood-based biomarkers and human post mortem neuropathology in the University of Kentucky Alzheimer's Disease Research Center autopsy cohort.

INTRODUCTION: Clinically, detection of disease-causing pathology associated with Alzheimer's disease (AD) and vascular contributions to cognitive impairment and dementia (VCID) is limited to magnetic resonance imaging and positron emission tomography scans, which are expensive and not widely accessible. Here, we assess angiogenic, inflammatory, and AD-related plasma biomarkers to determine their relationships with human post mortem neuropathology. METHOD: Plasma samples were analyzed using a digital immunoassay and pathological evaluation was performed by University of Kentucky Alzheimer's Disease Research Center neuropathologists. The association of plasma markers with neuropathology was estimated via proportional odds and logistic regressions adjusted for age. RESULTS: Included cases (N = 90) showed increased tau/amyloid beta (Aß)42 ratio, glial fibrillary acidic protein (GFAP), vascular endothelial growth factor A (VEGF-A), and placental growth factor (PlGF) were positively associated with higher level of AD neuropathological change, while higher Aß42/Aß40 ratio was inversely associated. Higher PlGF, VEGF-A, and interleukin 6 were inversely associated with chronic cerebrovascular disease, while Aß42/Aß40 ratio was positively associated. DISCUSSION: Our results provide support for the continued study of plasma biomarkers as a clinical screening tool for AD and VCID pathology.

Enhancing grant-writing expertise in BUILD institutions: Building infrastructure leading to diversity.

BACKGROUND: The lack of race/ethnic and gender diversity in grants funded by the National Institutes of Health (NIH) is a persistent challenge related to career advancement and the quality and relevance of health research. We describe pilot programs at nine institutions supported by the NIH-sponsored Building Infrastructure Leading to Diversity (BUILD) program aimed at increasing diversity in biomedical research. METHODS: We collected data from the 2016-2017 Higher Education Research Institute survey of faculty and NIH progress reports for the first four years of the program (2015-2018). We then conducted descriptive analyses of data from the nine BUILD institutions that had collected data and evaluated which activities were associated with research productivity. We used Poisson regression and rate ratios of the numbers of BUILD pilots funded, students included, abstracts, presentations, publications, and submitted and funded grant proposals. RESULTS: Teaching workshops were associated with more abstracts (RR 4.04, 95% CI 2.21-8.09). Workshops on grant writing were associated with more publications (RR 2.64, 95% CI 1.64-4.34) and marginally with marginally more presentations. Incentives to develop courses were associated with more abstracts published (RR 4.33, 95% CI 2.56-7.75). Workshops on research skills and other incentives were not associated with any positive effects. CONCLUSIONS: Pilot interventions show promise in supporting diversity in NIH-level research. Longitudinal modeling that considers time lags in career development in moving from project development to grants submissions can provide more direction for future diversity pilot interventions.

Child Abuse Recognition Training for Prehospital Providers Using Deliberate Practice.

BACKGROUND: In most states, prehospital professionals (PHPs) are mandated reporters of suspected abuse but cite a lack of training as a challenge to recognizing and reporting physical abuse. We developed a learning platform for the visual diagnosis of pediatric abusive versus non-abusive burn and bruise injuries and examined the amount and rate of skill acquisition. METHODS: This was a prospective cross-sectional study of PHPs participating in an online educational intervention containing 114 case vignettes. PHPs indicated whether they believed a case was concerning for abuse and would report a case to child protection services. Participants received feedback after submitting a response, permitting deliberate practice of the cases. We describe learning curves, overall accuracy, sensitivity (diagnosis of abusive injuries) and specificity (diagnosis of non-abusive injuries) to determine the amount of learning. We performed multivariable regression analysis to identify specific demographic and case variables associated with a correct case interpretation. After completing the educational intervention, PHPs completed a self-efficacy survey on perceived gains in their ability to recognize cutaneous signs of abuse and report to social services. RESULTS: We enrolled 253 PHPs who completed all the cases; 158 (63.6%) emergency medical technicians (EMT), 95 (36.4%) advanced EMT and paramedics. Learning curves demonstrated that, with one exception, there was an increase in learning for participants throughout the educational intervention. Mean diagnostic accuracy increased by 4.9% (95% CI 3.2, 6.7), and the mean final diagnostic accuracy, sensitivity, and specificity were 82.1%, 75.4%, and 85.2%, respectively. There was an increased odds of getting a case correct for bruise versus burn cases (OR = 1.4; 95% CI 1.3, 1.5); if the PHP was an Advanced EMT/Paramedic (OR = 1.3; 95% CI 1.1, 1.4) ; and, if the learner indicated prior training in child abuse (OR = 1.2; 95% CI 1.0, 1.3). Learners indicated increased comfort in knowing which cases should be reported and interpreting exams in children with cutaneous injuries with a median Likert score of 5 out of 6 (IQR 5, 6). CONCLUSION: An online module utilizing deliberate practice led to measurable skill improvement among PHPs for differentiating abusive from non-abusive burn and bruise injuries.

Baseline Characteristics of the 2015-2019 First Year Student Cohorts of the NIH Building Infrastructure Leading to Diversity (BUILD) Program.

Objective: The biomedical/behavioral sciences lag in the recruitment and advancement of students from historically underrepresented backgrounds. In 2014 the NIH created the Diversity Program Consortium (DPC), a prospective, multi-site study comprising 10 Building Infrastructure Leading to Diversity (BUILD) institutional grantees, the National Research Mentoring Network (NRMN) and a Coordination and Evaluation Center (CEC). This article describes baseline characteristics of four incoming, first-year student cohorts at the primary BUILD institutions who completed the Higher Education Research Institute, The Freshmen Survey between 2015-2019. These freshmen are the primary student cohorts for longitudinal analyses comparing outcomes of BUILD program participants and non-participants. Design: Baseline description of first-year students entering college at BUILD institutions during 2015-2019. Setting: Ten colleges/universities that each received <$7.5mil/yr in NIH Research Project Grants and have high proportions of low-income students. Participants: First-year undergraduate students who participated in BUILD-sponsored activities and a sample of non-BUILD students at the same BUILD institutions. A total of 32,963 first-year students were enrolled in the project; 64% were female, 18% Hispanic/Latinx, 19% African American/Black, 2% American Indian/Alaska Native and Native Hawaiian/Pacific Islander, 17% Asian, and 29% White. Twenty-seven percent were from families with an income <$30,000/yr and 25% were their family's first generation in college. Planned Outcomes: Primary student outcomes to be evaluated over time include undergraduate biomedical degree completion, entry into/completion of a graduate biomedical degree program, and evidence of excelling in biomedical research and scholarship. Conclusions: The DPC national evaluation has identified a large, longitudinal cohort of students with many from groups historically underrepresented in the biomedical sciences that will inform institutional/national policy level initiatives to help diversify the biomedical workforce.

Dusk to Dawn: Evaluating the effect of a hospital-based youth violence prevention program on youths' perception of risk.

BACKGROUND: Historically, youth violence prevention strategies used deterrence-based programming with limited success. We developed a youth violence prevention program, Dusk to Dawn (D2D), intended to improve youths' recognition of high-risk situations and teach new skills in conflict resolution. The aim of this study was to evaluate the effect of D2D on youths' perceptions of personal risk factors and high-risk situations. METHODS: Youth ages 12 years to 18 years were referred to D2D by community-based organizations, probation, or youth detention center. The youth completed a self-report survey before and after participating in D2D. RESULTS: One hundred eight youth participated in D2D. Pretest and posttest results for self-reported personal risk factors and high-risk situations for violence are presented. For personal risk factors, a statistically significant increase in the perception that family (p < 0.01) and other issues (p < 0.05), and a decrease in the perception that school problems (<0.05) were seen as important personal risk factors. For high-risk situations, increases in the perception that peer violence and substance use as high-risk situations were seen as significant at the trend level (p < 0.10). Of the 60% of participants who answered questions regarding satisfaction with D2D, 83.3% agreed or strongly agreed that D2D helped them to better understand violence and 83.3% would recommend D2D to others. CONCLUSION: Youth violence prevention programming including an explicit discussion of how violence is learned and the role of family, friends, school, and a community in shaping youths' attitudes toward violence can effectively raise awareness of one's own risk factors. Risk factors for youth violence are often preventable or modifiable, making awareness of one's own risk factors a realistic target for youth violence prevention programs. LEVEL OF EVIDENCE: Therapeutic/Care Management, Level III.

Epidemiology of abusive head trauma in West Virginia children <24 months: 2000-2010.

BACKGROUND: Few states have published statewide epidemiology of abusive head trauma (AHT). OBJECTIVE: To examine the statewide epidemiology of AHT in West Virginia (WV), with the primary objective of establishing AHT incidence for comparison to national data, and to use as a baseline for comparison to incidence post-implementation of a statewide AHT prevention program. PARTICIPANTS AND SETTING: AHT cases in children less than 2 years old were identified from the 3 tertiary pediatric centers in WV. METHODS: Cases were identified by using ICD-9 codes for initially identifying those with injuries which might be consistent with AHT, followed by medical record review to determine which of these met the criteria for inclusion as a case. Medical examiner data was used to find additional cases of AHT. Using the number of cases identified along with relevant census data, incidence of AHT was calculated. RESULTS: There were 120 cases of AHT treated in WV hospitals from 2000 to 2010, 100 of which were WV residents. The incidence was 36.1/100,000 children <1 year of age and was 21.9 cases per 100,000 children <2 years of age. Incidence in infants increased during the latter years (2006-2010) of the study to 51.8/100,000 compared to the incidence during 2000-2005, which was 24.0/100,000 (p < .01). CONCLUSIONS: Compared to US national, state and regional figures, the WV incidence of AHT was among the highest. In addition, the incidence of AHT increased significantly over the study period. Possible factors contributing to the rise in incidence are discussed.

Control of cellular adhesion and myofibroblastic character with sub-micrometer magnetoelastic vibrations.

The effect of sub-cellular mechanical loads on the behavior of fibroblasts was investigated using magnetoelastic (ME) materials, a type of material that produces mechanical vibrations when exposed to an external magnetic AC field. The integration of this functionality into implant surfaces could mitigate excessive fibrotic responses to many biomedical devices. By changing the profiles of the AC magnetic field, the amplitude, duration, and period of the applied vibrations was altered to understand the effect of each parameter on cell behavior. Results indicate fibroblast adhesion depends on the magnitude and total number of applied vibrations, and reductions in proliferative activity, cell spreading, and the expression of myofibroblastic markers occur in response to the vibrations induced by the ME materials. These findings suggest that the subcellular amplitude mechanical loads produced by ME materials could potentially remotely modulate myofibroblastic activity and limit undesirable fibrotic development.

Bioactive vapor deposited calcium-phosphate silica sol-gel particles for directing osteoblast behavior.

Silica-based materials are being developed and used for a variety of applications in orthopedic tissue engineering. In this work, we characterize the ability of a novel silica sol vapor deposition system to quickly modify biomaterial substrates and modulate surface hydrophobicity, surface topography, and composition. We were able to show that surface hydrophobicity, surface roughness, and composition could be rapidly modified. The compositional modification was directed towards generating apatitic-like surface mineral compositions (Ca/P ratios ∼1.30). Modified substrates were also capable of altering cell proliferation and differentiation behavior of preosteoblasts (MC3T3) and showed potential once optimized to provide a simple means to generate osteo-conductive substrates for tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2135-2148, 2016.

Primary Care of the Solid Organ Transplant Recipient.

The advancing science of transplantation has led to more transplants and longer survival. As a result, primary care physicians are more involved in the care of transplant recipients. Immunosuppressive therapy has significantly decreased rates of transplant rejection but accounts for more than 50% of transplant-related deaths, often due to infections and other risks related to long-term use. Cardiovascular disease is the leading cause of non-transplant-related mortality. Aggressive risk factor management is recommended for transplant recipients, including a blood pressure goal of less than 130/80 mm Hg and statin therapy in kidney, liver, and heart recipients. Fertility typically increases posttransplant, and female transplant recipients should avoid pregnancy for one year after surgery. The best contraceptive choice is usually an intrauterine device. Because of the increased risk of infection, patients should be tested for graft dysfunction or infection if suspicion arises. Testing should be coordinated with the transplant center. Malignancies are a common cause of death in transplant recipients, requiring careful attention to screening recommendations and informed discussions with patients. Family physicians should maintain an ongoing relationship with the transplant team to discuss medication changes and the risk of infection or graft rejection.

Application of sub-micrometer vibrations to mitigate bacterial adhesion.

As a prominent concern regarding implantable devices, eliminating the threat of opportunistic bacterial infection represents a significant benefit to both patient health and device function. Current treatment options focus on chemical approaches to negate bacterial adhesion, however, these methods are in some ways limited. The scope of this study was to assess the efficacy of a novel means of modulating bacterial adhesion through the application of vibrations using magnetoelastic materials. Magnetoelastic materials possess unique magnetostrictive property that can convert a magnetic field stimulus into a mechanical deformation. In vitro experiments demonstrated that vibrational loads generated by the magnetoelastic materials significantly reduced the number of adherent bacteria on samples exposed to Escherichia coli, Staphylococcus epidermidis and Staphylococcus aureus suspensions. These experiments demonstrate that vibrational loads from magnetoelastic materials can be used as a post-deployment activated means to deter bacterial adhesion and device infection.

S-nitroso-N-acetylpenicillamine (SNAP) derivatization of peptide primary amines to create inducible nitric oxide donor biomaterials.

An S-nitroso-N-acetylpenicillamine (SNAP) derivatization approach was used to modify existing free primary amines found in fibrin (a natural protein-based biomaterial) to generate a controlled nitric oxide (NO) releasing scaffold material. The duration of the derivatization reaction affects the NO release kinetics, the induction of controlled NO-release, hydrophobicity, swelling behavior, elastic moduli, rheometric character, and degradation behavior. These properties were quantified to determine changes in fibrin hydrogels following covalent attachment of SNAP. NO-releasing materials exhibited minimal cytotoxicity when cultured with fibroblasts or osteoblasts. Cells maintained viability and proliferative character on derivatized materials as demonstrated by Live/Dead cell staining and counting. In addition, SNAP-derivatized hydrogels exhibited an antimicrobial character indicative of NO-releasing materials. SNAP derivatization of natural polymeric biomaterials containing free primary amines offers a means to generate inducible NO-releasing biomaterials for use as an antimicrobial and regenerative support for tissue engineering.