INTRODUCTION: Fractures represent a common orthopaedic injury and create a large financial burden for the health care system. Non-union fractures often require surgery to assist the healing process. Understanding the origin of the postnatal skeletal stem cells will allow for locally delivered therapeutic treatments to be more exactly spatially targeted for fracture healing. Two forms of post-natal bone formation were studied, callus formation after fracture and ectopic bone growth. Both forms of bone formation closely follow the mechanisms of endochondral ossification. The Prx1 gene that is known to be expressed by skeletal stem/progenitor cells within the periosteal tissues was used to spatially follow this cell population during ectopic and fracture induced bone formation. OBJECTIVES: The purpose of this study was to define the cell lineages that arise from Prx1 expressing cells in fracture and ectopic bone models. METHODS: Prx1 expressing cells were tracked using Prx1CreER-GFP x RosaAi14 (dTomato indicator) and Prx1CreER-GFP x Ai14i (dTomato indicator) in the Rag1tm strain of transgenic mice. These mice strains respectively received a closed stabilized fracture or human demineralized bone matrix (DBM) that was surgically implanted onto the periosteal surface of the femur to initiate the development of ectopic bone. Tissue was collected at either day 10 or 14 post-fracture surgery or day 8 post-DBM implantation. Prx1CreER-GFP expression was induced by tamoxifen or control animals received no injection or corn oil. Three different tamoxifen induction protocols (30 days prior to surgery to allow for washout, three days prior to, or continuously after either fracture or ectopic bone induction were used. Fluorescent microscopy of the histological images were performed to assess the cell populations that expressed Prx1 and cell counting was used to quantify the percentages of Prx1 positive cells in specific regions of interest. qRT-PCR of Prx-1 mRNA expression was used to provide the relative gene expression of Prx1 in a variety of different tissues. RESULTS: Control animals that received corn oil or no Tamoxifen showed low levels (~5-15%) labeled cells, however there was a ~2 fold increase in labeling with Tamoxifen washout. Labeled cells were present within calvaria, femur, tibia, and forelimb bones, while very low amounts were located at the sternum rib junction but were absent in the vertebra. Up to 55-65% of the cells within fracture callus and ectopic bone models showed Prx1 labeled in both cartilage and bone cells. Most interestingly however was the increased presence of Prx1 positive cells throughout the skeletal muscle, growth plate, medial layers of blood vessels, and adipose tissue of appendiculum. Labeling was not in muscles of the chest and back. Upon investigation of several different organs very low levels of Prx1 positive cells in the kidney, aorta and brain.. However, no Prx1 cells were located in the heart, spleen or liver tissues. CONCLUSIONS: While a population of Prx1 cells was shown previously to be localized to the periosteum and contribute to fracture repair this study showed these cells in multiple tissue types throughout the appendiculum. Our results are the first in vivo demonstration to suggest that there is a multi-potential post natal mesenchymal stem population. This Prx1 positive cell population was not seen in ectopic bone that was induced outside the appendiculum indicating that these cells retained their original embryonic specification into the adult animal.

Neurodegenerative diseases generally correlate with age; as the US population’s average age increases, neurodegenerative ailments will contribute a greater burden on the health care system. One of the most prevalent, Alzheimer’s disease, is known to associate with tau proteins with evidence suggestive that abnormal function may initiate neurodegeneration. The entorhinal cortex is one of the earliest regions found to exhibit neuronal atrophy in Alzheimer’s disease. This study analyzed two major neuron types in the entorhinal cortex, fan cells and stellate cells, using the P301S mouse model for tauopathy. Laser-scanning confocal microscopy and software were used to reconstruct and analyze dendrite morphology between the two neuron types. Our results found that stellate cells of transgenic mice exhibited dendritic atrophy, with decreases in morphological parameters such as dendritic length, dendritic complexity, and number of primary dendrites in comparison to wild-type stellate cells. On the other hand, fan cells of transgenic mice did not show decreases in these parameters. Instead, fan cells of transgenic mice showed increases in surface area and volume in a convex hull model, as well as an increase in total Sholl radius from soma in comparison to wild type fan cells. These results suggest that neurons may respond differently to tauopathic stress. Additionally, noting distinct morphological differences between wild type fan cells and stellate cells, such as stellate cells having greater spine density and basal dendritic extensions, our data hints that morphological characteristics may predict susceptibility to pathogenic effects of tau.

Glioblastoma multiforme (GBM) represents the deadliest brain cancer pathology. Current therapeutic treatment focuses on surgical resection of tumors, followed by adjuvant radiation and/or chemotherapy. The invasive nature of GBM however limits the effectiveness of such therapy. Drug development for GBM has centered on attempts to manage this infiltrative capacity. One avenue of such development focuses on aberrant cellular signaling pathways characteristic of malignancies. This study sought to understand the mechanism by which glycogen synthase kinase 3 (GSK-3) inhibitors differentially regulate GBM migration. Measurement of in vitro cellular migration has traditionally utilized Boyden chamber (transwell) assays and collagen migration assays. Administration of known GSK-3 inhibitors demonstrate a differential effect, whereby migration is inhibited in transwell assays, but maintained in the collagen assay. Cell aggregates from 4 different GBM cell lines were utilized in comparison of GSK-3 inhibitor effects in both the transwell and collagen assays. Contrary to previous findings, GSK-3 inhibitors demonstrated limited effect in reducing migration in the transwell assay, while demonstrating modest effects in the collagen assay. A mechanistic understanding of GSK-3 inhibitor function remains elusive. Previous studies have demonstrated GSK-3 effects on various cytoskeletal proteins, including the WAVE-2 complex, vital for cytoskeletal stability. Administration of GSK-3 inhibitors had previously led to a downregulation of WAVE2 levels. After administration of known GSK-3 inhibitors, this study failed to reproduce previous differences in total WAVE2 protein levels compared to control untreated samples. This evidence indicates a different mode of cytoskeletal regulation must be driving GSK-3 inhibition’s effect on GBM migration. GSK-3 inhibitors represent one promising class of chemotherapeutic agents for treatment of GBM. This study corroborated previous findings about the effect of classical GSK-3 inhibitors (BIO, CHI99021) in reducing GBM migration. Further investigation is necessary to isolate the specific cellular mechanisms responsible for GSK-3’s effects. With rapid development of other therapeutic strategies, GSK-3 inhibitors present one class of drugs available to clinicians for effective therapeutic management of GBM.

For the past 40 years, most patients with Primary Hyperparathyroidism (PHPT) have presented with the asymptomatic form of PHPT. Despite the dominance of the asymptomatic PHPT phenotype, current National Institutes of Health (NIH) indications for parathyroidectomy fail to identify as many as 80% of patients afflicted with asymptomatic PHPT. To date, studies of the therapeutic benefits of parathyroidectomy among asymptomatic PHPT patients have relied on general health questionnaires and patient reports of their satisfaction with the surgery. The purpose of the present study was to implement objective, quantifiable metrics in assessing whether or not asymptomatic PHPT patients experience improvements in domains salient to them such as mobility and cognitive function following parathyroidectomy. This information may help set the foundation for more accurately identifying patients who would benefit from parathyroidectomy. We hypothesized that asymptomatic patients would exhibit improvement in motor-cognitive outcomes following successful parathyroidectomy. We performed a single-center prospective assessment of gait, frailty, and motor-cognitive function among patients diagnosed with PHPT. Demographics, medical history, and perioperative labs were recorded. Pre- and post-surgical measures included the Fried frailty criteria, the PROMIS 10 Global Health Scale, and gait analysis under habitual (ST), walking while performing working memory test (dual-task: DT), and fast-walking conditions, an upper extremity frailty (UEF) test, and an interactive trail-making task (iTMT) . Descriptive statistics, Chi-squared, 2-sample t tests, and repeated measures analysis of variance were applied where appropriate. 22 parathyroidectomy patients (male 7; 31.8%); median age of 54.9 (standard deviation=15.5) years participated. The prevalence of frailty/pre-frailty was 60% at baseline and reduced to 33% at 3 weeks post-op. PROMIS 10 physical health improved significantly by 3 months post-op (d=0.93, p=0.010). DT and fast walk velocities were significantly increased by 3 weeks post-op (p<0.050) with highest effect size observed during DT conditions (24%, Cohen's effect size d=1.30 , p=0.017). ST velocity increased but not significantly (17.5%, d=0.46, p=0.422). Results from UEF tests and iTMT did not achieve statistical significance at any visit date. Asymptomatic PHPT patients experience significant resolution of motor-cognitive symptoms as measured by DT gait and PROMIS 10 Global Health Scale following parathyroidectomy performed by a skilled surgeon.

Irritable bowel syndrome (IBS) is the most common chronic functional gastrointestinal disorder that affects approximately 11% of the global population with a higher prevalence in women and those under the age of 50. IBS is characterized and diagnosed by the presence of a group of symptoms including abdominal pain, bloating or distension accompanied by altered bowel movements. A positive diagnosis of IBS can be made in the presence of well-defined, validated diagnostic criteria and in addition to the exclusion of organic disease with minimal testing. The lack of specific therapeutic targets makes treatment of IBS very difficult and its management is focused on symptom relief. IBS has a well-established high comorbidity with anxiety, depression, and psychosomatic disorders which contributes significantly to a substantial burden of illness. IBS patients exhibit a markedly decreased quality of life, decreased work productivity and increased absenteeism from work, and increased direct healthcare utilization (such as office visits, medical tests, and specialty referrals), resulting in a large economic burden for society. Despite this, effective pharmacologic and non-pharmacologic treatment options are limited and many patients with IBS do not achieve complete symptom relief long term and continue to suffer from IBS symptoms. Early pioneering in the study of this disease has called for a biopsychosocial model, a model in which psychological and social factors are also considered in IBS treatment. Through consideration of this model, it has been discovered that the disease has strong ties with early life environment, daily stress, and coping skills. Research in the past decades has established IBS as a disease of neurogastroenterology and involves disturbances in the brain-gut axis, the connection between the central nervous system and enteric nervous system. The brain-gut axis is organized in hierarchies with the first control level consisting of the enteric nervous system (ENS) sensory, muscular, and interneurons, all of which form reflex circuitry to control gastrointestinal (GI) motility and sensation among other functions. The central nervous system (CNS) synapses onto these circuits via vagal and spinal afferents. Information from the luminal GI tract is processed in the higher cortical structures of the brain, particularly in the hypothalamus, amygdala, anterior cingulage cortex (ACC) and prefrontal cortex (PFC). These structures are also important for homeostasis and regulation of attention, emotion, and behavior. Disturbances of these pathways result in peripheral and eventually central sensitization, the subject of this thesis. Sensitization in IBS includes visceral hypersensitivity, increased pain perception, and increased GI motility. Due to the cortical regions where this information is processed, these physical symptoms often have a complex interplay with psychological symptoms including anxiety, fear, and stress. The connection between the physical symptoms and psychological symptoms lies in the pain matrix and emotional motor system. This has been confirmed by many brain imaging studies comparing normal individuals with IBS patients testing visceral, somatic and cutaneous pain as well as anxiety and depression levels. IBS patients, unlike control subjects, have been found to have increased pain perception localizing to all these regions and they also rate the pain as more unpleasant, a psychological factor, than normal patients. In addition to increased cortical activation, IBS patients have increased corticotropin releasing factor in the amygdala promoting anxiety and increasing stress levels and GI symptoms. Of note is the fact that stress is both a cause and effect of IBS symptoms and often compounds symptoms due to the cyclical nature of stress and chronic pain. Because stress ties in with both the physical and psychological symptoms faced by IBS patients, implementation of psychological treatment in IBS management is of great importance and have demonstrated improved outcomes in IBS patients. Psychological treatments with empirical evidence are discussed in this thesis and include cognitive behavioral therapy, psychodynamic psychotherapy, hypnotherapy, and mindfulness/relaxation exercises. Whether these all treatments tie into the alterations in cortical processing in brain-gut function is a topic that is yet to be explored.

OBJECTIVE: We assessed the impact of paid family and medical leave durations on the health outcomes of employees and their families. Using previous literature and relevant studies, we aimed to formulate evidence-based recommendations for the duration of paid family and medical leave that would promote optimal health outcomes. METHODS: PubMed was utilized to identify relevant literature. The concept of paid leave was organized into four main categories: maternity leave, parental leave, personal medical leave, and leave for children’s health needs. Literature searching, data abstraction, and analyses were performed. Weekly discussions with the Medical Decision Points team were also conducted to finalize article selection, organization, and data analysis. RESULTS: Maternal mental health and breastfeeding continuation were positively associated with maternity (i.e., maternal disability) leave durations of 12 to 16 weeks and longer. Infant morbidity and mortality, vaccination uptake rate, breastfeeding continuation all improved with up to six months of parental (i.e., parent bonding) leave. There was limited evidence regarding personal medical leave and leave for children’s health needs. Typical durations of hospitalization, recovery, work and school absence were analyzed to formulate appropriate paid leave durations. CONCLUSION: Evidence suggests that the 12 weeks of unpaid leave offered by the Family and Medical Leave Act (FMLA) is inadequate in providing employees and their families with health sustaining benefits. We recommend at least four months of paid maternity leave and six months of paid parental leave for each new child. We also recommend up to six months of paid personal medical leave for each serious illness and at least six weeks (for up to six months) of paid family leave for each child’s serious illness, with substantial flexibility to account for both acute illness requiring sustained care and recovery periods requiring more intermittent care.

BACKGROUND: Chronic kidney disease is an insidious, long-term disease, characterized by progressive decline in kidney function over time. It currently affects millions of Americans, and millions more are at risk to develop the disease in the future. There is no cure-all treatment for chronic kidney disease. Current management involves slowing the progression in the decline of kidney function, managing associated comorbidities that contribute to the disease, including hypertension and type 2 diabetes mellitus, and treating disease complications. The overall goal of treatment is to delay the time to dialysis and reduce the risk of cardiovascular events. Current management also involves a set of dietary restrictions. LITERATURE REVIEW: Studies that have been conducted using the current dietary recommendations have been shown to have some benefit. However, other studies have demonstrated no advantage using these dietary guidelines. Few studies have looked at how the source of food affects renal function over time. A review of the literature will highlight the importance of the source of food consumption for patients with chronic kidney disease. PROPOSED PROJECT: The study being proposed is a randomized-controlled trial comparing current dietary recommendations with a plant-based diet for patients with chronic kidney disease. The study participants will have a baseline assessment of renal function with follow-up throughout. The trial will last for 36 months. The primary outcome being measured is the change in estimated glomerular filtration rate over time with secondary outcomes being urinary albumin levels, serum bicarbonate, and serum phosphorus. CONCLUSION: The data from this trial will help conclude if a plant-based diet is more effective than a traditionally recommended diet at delaying the decline in glomerular filtration rate for patients with chronic kidney disease.

Corneal injury, accompanied by improper wound repair, is the 4th highest cause of preventable blindness according to the World Health Organization. The cornea, which is the most densely innervated structure in the human body, serves to protect the delicate internal environment of the eye from damage. The integrity of this intricate nerve structure is critical in our ability to sense even the slightest insult to the corneal surface, with reduced sensitivity leading to increased susceptibility to trauma. In diabetes, decreased corneal sensitivity secondary to diabetic peripheral neuropathy can lead to increased corneal abrasion, ulceration, and even blindness. The P2X7 purinoreceptor is an ion channel that is expressed by the epithelium along with the intra-epithelial nerves and stromal nerves. The goal of our study was to use a type 2 diabetic mouse model (DIO) to characterize the changes in P2X7 localization and potentially correlate our results with changes in trafficking and sensory nerve loss. We hypothesized that the P2X7 receptor acts to sense changes at the leading edge and this fine tuned regulation is altered during the diabetic disease state. Further understanding of the corneal changes that occur in diabetes can help us better monitor progression of diabetic complications as well as develop new therapeutics for the treatment of diabetic corneal dysfunction.

BACKGROUND: Chronic, non-communicable diseases (NCD), such as cardiovascular disease and cancer, have overtaken communicable disease as the leading cause of morbidity and mortality worldwide. However, despite the substantial toll these diseases have on populations, patients suffering from these illnesses are often overlooked in the aftermath of an environmental disaster. Without proper disaster preparedness, these populations are often left vulnerable: without access to disease-modifying treatments or life-saving therapies. OBJECTIVE: This is a proposed disaster event health initiative for incorporating oncology care into disaster relief services worldwide. This study hypothesizes that with increased access to providers, resources, and cancer therapies during a disaster event, interruptions in patient oncology care will be minimized. METHODS: This disaster event health initiative consists of a detailed proposal for deploying a specialized oncology unit alongside traditional disaster response teams in an effort to decrease interruptions in patient oncology care. Depending on the severity of the disaster, available adjunct healthcare facilities, potential length of stay, most commonly used cancer therapies, and traditional patient: provider ratios, this proposal will inform the oncology unit assembly. Study measurables, such as how many patients seen, cancer diagnoses encountered, and most frequently used cancer therapies, will be collected using a standardized form. In addition, information regarding perceived patient satisfaction will be collected. System variable measures will be analyzed using frequency and average means whereas qualitative information will be coded for emerging themes. These measures of initiative efficacy will be used to revise and optimize future unit deployments. CONCLUSION: Worldwide morbidity and mortality from non-communicable diseases, such as cancer, are steadily increasing. When acute environmental disasters strike, access to essential healthcare resources is disrupted, leaving these vulnerable populations without life-saving therapies they desperately need. These interruptions in cancer treatment plans result in poorer, long-term patient outcomes, compounding the effects of the disaster situation. By deploying a specialized oncology unit with disaster response teams during the initial recovery process, interruptions in cancer care will be minimized, ultimately decreasing long-term morbidity and mortality outcomes in this vulnerable patient population.

BACKGROUND: Children with autism spectrum disorder (ASD) are at high-risk for being obese. Little is known about how pediatricians address weight management in children with ASD. OBJECTIVE: To examine the attitudes, self-efficacy, practices and barriers to obesity management in children with ASD among pediatricians. METHOD: We conducted an anonymous survey of a random sample of 1500 pediatricians using the American Medical Association Masterfile. We used Likert-scale items to examine attitudes, self-efficacy, practices and barriers to obesity management in ASD. The survey included a fictional clinical vignette of a clinic visit for an obese child. Participants were randomized to a vignette with a child with ASD or a child without ASD. We compared responses by survey vignette type using chi-square tests and used logistic regression to examine the association between self-efficacy and counseling frequency. RESULTS: 327 respondents completed the survey (24% response rate). Respondents were mostly female (65%) and worked in private practice (61%). Although 62% of respondents agreed pediatricians should be the main providers to manage obesity in children with ASD, few reported receiving adequate training to do so. Pediatricians were more likely to refer to specialists for a child with ASD compared to a child without ASD. Higher self-efficacy was associated with increased counseling frequency (aOR: 2.58 [1.57, 4.24]). Top reported barriers were lack of caregiver concern and lack of physician time. CONCLUSION: Pediatricians report obesity in children with ASD as challenging to manage. Training programs may result in increased counseling frequency around obesity for children with ASD. / 2019-11-08T00:00:00Z