Browsing by Author "Graham, James, advisor"
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Item Embargo Acute care rehabilitation utilization, access, and outcomes among hospitalized adults with traumatic brain injury(Colorado State University. Libraries, 2024) Bukhari, Rayyan A., author; Graham, James, advisor; Weaver, Jen, committee member; Davalos, Deana, committee member; Sharp, Julia, committee memberObjective: The purpose of this dissertation was to conduct three research studies aimed at gaining a comprehensive understanding of the barriers and facilitators to equitable access to and timing of rehabilitation services, community discharge, and unplanned 90-day post-discharge hospital readmission among individuals hospitalized with Traumatic brain injury (TBI). Introduction: There are approximately 2.5 million TBI-related emergency department visits, 288,000 TBI-related hospitalizations, and 61,000 TBI-related deaths reported each year (Centers for Disease Control and Prevention, 2019). TBI is associated with high rates of disability, including limitations in performing basic activities of daily living (ADLs), such as self-care, and/or in performing physical tasks, such as mobility (Klima et al., 2019; Jessica Lo et al., 2021; Whiteneck et al., 2016). Individuals who are hospitalized with TBI should receive equitable access to multidisciplinary care, including rehabilitation services (occupational therapy [OT], and physical therapy [PT]) to address potential self-care issues, physical limitations, and cognitive deficits (National Academies of Sciences & Medicine, 2022). Early onset of acute care rehabilitation services can have positive long-term benefits for patients, including improved function, increased mobility, and enhanced quality of life (Andelic et al., 2012; Bernhardt et al., 2017; C. Y. Wang et al., 2021). A primary focus of acute care rehabilitation services is to improve patients' functional performance (Ejlersen Wæhrens & Fisher, 2007). Following acute care stays, community discharge is generally viewed as quality care indicator in acute care settings (Department of Health and Human Services [HHS], 2019). Readmission is a common concern for those who have chronic illnesses or injuries, and it is associated with higher healthcare expenses and lower quality of care (Jencks et al., 2009). Readmission rates after TBI contribute considerably to these costs, making lowering readmission rates a universal goal (Canner et al., 2016). Despite research advances and policy changes, barriers and challenges remain facing individuals with TBI (National Academies of Sciences & Medicine, 2022). Not all individuals with TBI have early access to rehabilitation services, are discharged to the community, or can avoid hospital readmission. Although several studies have addressed these issues in general population, variability in community and personal level factors among individuals with TBI need to be addressed (Office of Disease Prevention and Health Promotion & Services., 2020). Therefore, these dissertation studies are aimed at providing empirical support, further understanding, and increasing our knowledge around factors that influence individuals with TBI acute care rehabilitation services utilization and outcomes. Method: This dissertation is comprised of three studies. In Study One, we investigated how Social Determinants of Health (SDoH) impact access to and timing of rehabilitation services. Multivariable logistic and Cox regression analyses (i.e., time-to-event analyses) were used to calculate odds ratios for the likelihood of receiving OT and PT services, and hazard ratios for the duration to initiation of services among those who received these services. In Study Two, we explored whether the relationship between acute care OT/PT utilization and community discharge is moderated by functional or physical performance at discharge. Multivariable moderation logistic regression models were used to calculate odds ratios for the likelihood of community discharge among those who utilized OT/PT services. In both OT and PT models, we computed the main effect of OT/PT utilization on community discharge, the main effect of functional/physical (ADL/Mobility) performance scores at discharge on community discharge, and the moderating effect of ADL/mobility scores on the relationship between OT/PT utilization and community discharge. In Study Three, we examined the association between discharge functional status and unplanned hospital readmission. Logistic regression was performed to calculate odds ratios for the likelihood of unplanned 90-day hospital readmission among those who received rehabilitation services during their acute care stay. Results: In Study One, all community-level SDoH such as education attainment, income, and rurality did not show significant associations with access to or timing of acute rehabilitation services (p-values= 0.09 – 0.95). In Study Two, both ADL/mobility performance scores at discharge significantly moderated the relationship between OT/PT utilization and community discharge (ORs= 0.99, 95% CIs [0.98, 1.00]). In Study Three, neither discharge functional nor mobility scores were associated with readmission (p-values= 0.14 – 0.17). Among the three dissertation studies, several covariates such as age, presence of a significant other, race/ethnicity, health insurance type, TBI severity, length of stay, and comorbidity burden showed significant associations with access to or timing of acute rehabilitation services, community discharge, and readmission status (p-values= 0.04 – <0.001). Conclusion: Further investigations are needed to 1) ascertain whether our community-level SDoH variables, based on the first three digits of zip codes, adequately capture individual experiences and their impact on healthcare, or if community-level education, income, and rurality genuinely do not affect access to and timing of therapy services for hospitalized patients with TBI; 2) determine whether the consideration of ADL/mobility scores at discharge alone limits our understanding of the relationship, failing to encompass other patient-level factors that could either facilitate or impede a safe community discharge; and 3) determine whether discharge functional and mobility scores were too restrictive in capturing the full benefits of acute care rehabilitation services in reducing the risk of unplanned 90-day readmission risk in hospitalized patients with TBI.Item Open Access Characterization of equine sperm attributes and selection for intracytoplasmic sperm injection(Colorado State University. Libraries, 2018) Gonzalez-Castro, Raul A., author; Carnevale, Elaine, advisor; Graham, James, advisor; Seidel, George, committee member; Gerrit, Bouma, committee member; Ann, Hess, committee memberWhen performing intracytoplasmic sperm injection (ICSI), many in vivo mechanisms for sperm selection are bypassed; however, sperm must still be capable of activating the oocyte for successful fertilization. Limited information is available for horses on the effect of sperm preparation method and sperm characteristics that affect ICSI outcome. The overall objectives of this dissertation were to: 1) study the association between sperm sorting methods, sperm population characteristics, and equine ICSI outcome, and 2) characterize sperm oocyte activating factors in stallion sperm, such as phospholipase C zeta (PLCz) and postacrosomal WW binding protein (PAWP). In Experiment 1, a microfluidic device was used to sort frozen-thawed sperm from stallions (n=19), which resulted in a sperm subpopulation with improved motility, morphology, viability and DNA integrity (P<0.05) compared to the original sample. Then, microfluidic sorting was compared with the swim-up procedure and density gradient centrifugation. Swim-up was the least effective method to separate equine sperm. Microfluidic sorting and density gradient centrifugation sorted a sperm subpopulation with similar parameters, improving motility, viability and DNA integrity. After ICSI (n=45), no differences (P>0.3) were observed for cleavage and embryo development among sorting methods. In Experiment 2, sperm population parameters from which individual sperm were selected for injection were analyzed immediately after ICSI and correlated with the outcome. Sperm morphology, viability, membrane integrity measurement of hypoosmotic swelling and DNA integrity were evaluated in frozen-thawed sperm (n=114) used for ICSI in a program. Among sperm parameters, viability correlated positively with normal morphology and membrane integrity (P<0.05). Normal sperm morphology and DNA integrity were not predictive of ICSI outcome. Viability was predictive of cleavage and blastocyst formation, and membrane integrity was predictive of early pregnancy (P<0.05). In Experiment 3, PLCz and PAWP were identified, localized and quantified in stallion sperm, and the relationship with other sperm parameters was investigated. PLCz was identified as a 71 kDa protein and located in the acrosomal and postacrosomal region, midpiece and principal piece of the tail. PAWP was identified by two bands of ~28 and ~32 kDa, located in the postacrosomal region, midpiece and principal piece of the tail. The expression of PLCz and PAWP correlated positively (P=0.04) when analyzed for sperm of 14 stallions. Flow cytometric assessment was feasible for PLCz, but not for PAWP. Expression and percentages of positive labeled sperm for PLCz varied among stallions (n=21). Expression of PLCz was higher in live than dead sperm (P<0.005), and DNA fragmentation correlated negatively with PLCz expression (P<0.04). In conclusion, microfluidic sorting and density gradient centrifugation resulted in a subpopulation of sperm with high quality parameters for ICSI. The probability of sperm-injected oocytes to develop into an embryo and to establish pregnancy improved when sperm were selected from a sample population with higher viability and membrane integrity. This is the first report that describes PAWP in equine sperm, which displayed a novel localization in the midpiece and principal piece of sperm tail in addition to the expected postacrosomal region. Protein levels of PLCz and PAWP were correlated in sperm heads. The expression of PLCz in sperm varied widely among stallions and was associated with DNA integrity. Sperm membrane integrity is indicative of well-maintained plasma membrane architecture, conserving sperm quality and membrane components that are required for oocyte activation and early embryo development. Assessment of PLCz in stallion sperm represents a potent feature to investigate sperm quality for equine ICSI, and potentially can serve as a prognostic biomarker for oocyte activation ability and male infertility. Further studies are needed to determine the relationship between PLCz and PAWP with fertility in horses.Item Open Access Identification of clathrin and dynamin II in the porcine ovary supports the presence of clathrin-mediated endocytosis(Colorado State University. Libraries, 2016) Bacon, Margaret Leese, author; Graham, James, advisor; Eckery, Douglas, advisor; Callahan, Gerald, committee member; Bruemmer, Jason, committee memberThe feral swine population in the United States has grown to 6 million animals located in 41 states, and causing an estimated $1.5 billion annually in damages and control. Feral swine are well-known for spoiling crops, preying on smaller wildlife, spreading disease, and damaging the land’s ecology. In 2014, the federal government initiated the Animal Plant and Health Inspection Services (APHIS) National Feral Swine Damage Management Program to combat this overabundant wildlife population. One of five research areas identified as a key component in the advancement and improvement of tools and methods to manage feral swine is the development of reproductive inhibitors that can cause permanent sterility. Successful reproduction in mammals depends on an adequate number of healthy oocytes present in primordial follicles within the ovaries. Maintenance of the primordial follicular pool requires the coordinated actions of both oocyte survival factors and factors that maintain the follicles in a non-growing state until they are activated to grow. There is a finite number of primordial follicles in the ovaries of mammals, which if destroyed would leave the animal permanently sterile. Relatively little is known about the cellular communication mechanisms utilized by primordial follicles. The purpose of this study was to investigate whether primordial follicles express components of clathrin-mediated endocytosis (CME), the most common form of receptor-mediated endocytosis used in eukaryotes. This process, if present, could be exploited as a method to deliver chemosterilants to the primordial follicle pool. This study focused on determining the expression and localization of two key components of this CME, clathrin and dynamin II. Ovaries from 6 piglets and 6 gilts were bisected longitudinally, fixed in formalin, embedded in paraffin, and cut into 5µm thick sections which were mounted on microscope slides. Fluorescent immunohistochemistry using specific antibodies labeled with fluorescein isothiocynate was performed to determine the expression and localization of clathrin and dynamin II on the mounted tissue sections. Expression of clathrin and dynamin II was revealed in the cytoplasm of oocytes of all follicular stages examined, suggesting that CME could be a mechanism of cell signaling in porcine oocytes. A second aim of this study was to establish methods to visualize and characterize the internalization process in pig oocytes. The isolation of primordial follicles and oocytes and the live cell imaging of FM1-43 membrane probe uptake was completed. Primordial follicle isolation was attempted in piglet ovaries using a combination of chemical and mechanical methods. This process used enzymatic digestion and filtration of chopped cortical tissue from porcine ovaries. Mature oocytes were imaged over time after the addition of FM1-43. This established a protocol for live cell handling and imaging that would be useful in future studies. In addition, several ligands and their receptors that may utilize CME were investigated in porcine oocytes. The development of tools and methods to characterize cellular communication mechanisms in oocytes can contribute to the formulation of a chemosterilant to be used to cause non-lethal permanent sterility in feral swine.Item Open Access Investigation of assisted reproductive technologies (ART) for conservation of Bovidae(Colorado State University. Libraries, 2022) Benham, Hayley Marie, author; Barfield, Jennifer, advisor; Graham, James, advisor; Krisher, Rebecca, committee member; Duncan, Colleen, committee memberThere is an ongoing loss in global biodiversity in both wildlife and domestic species, creating a need to protect and preserve valuable genetics for the maintenance and sustainability of these populations. One of the proposed strategies to combat this loss is through the use of assisted reproductive technologies (ART), not as a replacement to natural breeding but as a strategy to augment and increase the tools we have to preserve genetic diversity. Currently, the application of ARTs is not broadly used as there are gaps in knowledge of species-specific reproductive biology and gamete biology, hindering the ability to make fast progress in implementing these techniques for conservation purposes in species and populations that are rapidly declining. ARTs used in domestic species in the Bovidae family, including cattle, have been developing over the past century, and recently are being adapted for use in non-domestic Bovidae. Arguably, one of the most critical ARTs developed for genetic rescue and conservation goals has been the successful utilization of cryopreservation techniques, which has allowed for the creation of genetic resource banks (GRBs), which are biorepositories for gametes, embryos, and tissues. Through GRBs breeding programs can achieve similar or greater levels of heterozygosity and increase the effective population size as represented by embryos and germplasm, compared to captive populations. In this work, we describe studies developing in vitro oocyte maturation (IVM) and in vitro embryo production (IVP) techniques used for the preservation of valuable bison genetics using gametes collected post-mortem, and cryopreservation techniques of bovine oocytes and ovarian tissue for fertility preservation. Using oocytes collected post-mortem, from bison within the YNP herd (a population with endemic brucellosis) we created disease-free embryos for subsequent transfer into healthy surrogate bison. The transfer of brucellosis-free embryos resulted in the live birth of a healthy brucellosis-negative bison calf. Next, by assessing the follicle size and duration of in vitro maturation (IVM) of bison oocytes collected from abattoir ovaries, out of season, we determined that seasonality does impact oocyte competence and blastocyst production, although viable bison embryos can be created independent of seasonal effects. While cryopreservation of female gametes in bovid species remains experimental, vitrification of oocytes may provide an opportunity for infusing greater genetic diversity into future generations. By assessing mitochondrial function of bovine oocytes during vitrification, we found that germinal vesicle (GV) stage oocytes may require additional support through the vitrification process, as they demonstrated a reduced ability to handle cryo-induced oxidative stress post-vitrification. Additionally, vitrification of bovine ovarian cortical tissue coupled with techniques for vitro activation (IVA) of primordial follicles may be an alternative way to preserve female germplasm. Follicle viability in bovine ovarian cortical tissue was partially preserved after vitrification, making it feasible to biobank vitrified tissue from valuable domestic or wild Bovidae, while in vitro tissue culture and/or IVA treatments significantly reduced tissue and follicle viability was unsuccessful. Further investigation of germline preservation in Bovidae is needed before these techniques can be broadly implemented. These ARTs are a toolbox of approaches to conserve biodiversity and valuable genetics through production, use, and preservation of tissue, gametes and embryos.Item Open Access Localization of nerve growth factor-β in the stallion reproductive tract(Colorado State University. Libraries, 2020) Mickelson, Alison, author; McCue, Patrick, advisor; Graham, James, advisor; Magunda, Forgivemore, committee memberNerve growth factor-β (NGF-β) is a protein produced in the reproductive tract of camelids (camels, llamas, and alpacas) that has been identified as the ovulation inducing factor in seminal plasma. NGF-β from seminal plasma deposited into the reproductive tract of the female camelid acts systemically to stimulate secretion of luteinizing hormone (LH) from the anterior pituitary, which in turn induces follicle maturation and ovulation. The objectives of the present study were to 1) determine if NGF-β is present in the reproductive tract of the stallion and 2) identify the specific site(s) of production. The hypotheses were that NGF-β would be present in the stallion reproductive tract and would primarily be localized in Sertoli cells of the testis and the prostate gland. Immunohistochemistry on paraffin embedded paraformaldehyde fixed tissues was performed using a rabbit polyclonal anti-NGF-β antibody on a total of six male equine reproductive tracts, including a one-day old colt, a one-year old colt and 4 adult stallion tracts. Strong immunostaining was observed in the efferent ducts of the testis and the epithelial cells of the prostate, seminal vesicles, bulbourethral glands and ampullae. Weaker NGF-β staining was noted in Leydig cells, Sertoli cells and spermatogonia within the testes and in epithelial cells of the epididymis. In conclusion, immunohistochemistry revealed that NGF-β is present in the stallion reproductive tract and the protein is primarily present in the efferent ducts of the testes and in all accessory sex glands.Item Open Access Mucosal immunization of mice with a recombinant Salmonella choleraesuis that expresses a multimeric gonadotropin releasing hormone fusion protein(Colorado State University. Libraries, 2011) Kemp, Jeffrey M., author; Graham, James, advisor; Huyvaert, Kathryn P., committee member; Bowen, Richard, committee member; Miller, Lowell, committee member; Rhyan, Jack, committee memberTo view the abstract, please see the full text of the document.Item Open Access Relationships between the wellness of older adults, health status, participation, and social determinants of health: a cross-sectional analysis using the National Health and Aging Trends Study(Colorado State University. Libraries, 2022) Parenti, Victoria, author; Graham, James, advisor; Schoessow, Kim, committee member; Miller, Ray, committee memberObjectives: The primary objective of the current study is to explore the independent effects of different types of health and participation variables on subjective well-being among community-dwelling older adults. A secondary objective is to examine the roles that social determinants of health, including environmental, economic, and social factors, may play in mediating those relationships. Data Source: The National Health and Aging Trends Study (NHATS) includes survey data from a large, nationally representative sample of Medicare beneficiaries ages 65 and older. The data capture a snapshot of later-life functioning, including information on health conditions, self-care, well-being, participation, living arrangements, and many more. NHATS data were developed for public use and have been used in more than 400 scientific publications. Participants aged 65 and older were drawn from Round 9 of NHATS conducted in 2019. Methods: Participants were included in the final sample if they resided in the community and completed a sample person interview (no proxy person interviews were included). Main variables being assessed include the 11 items of Well-Being, hospitalizations, general self-rated health, depressive symptoms, and participation in social activities. Proxy variables from the NHATS were selected to represent the individual domains of the social determinants of health, including economic stability, education, healthcare access, social and community context, and neighborhood and built environment. Bivariate and regression analyses were conducted to explore independent relationships and mediation effects. Results: The data indicate that hospitalizations, self-rated health, depressive symptoms, and participation in social activities are independently associated with subjective well-being. Additionally, indicators for economic stability, education, health literacy, and community context were independently associated with well-being among the sample of Medicare beneficiaries. There was one mediating effect of an individual SDOH domain on the relationship between hospitalizations and subjective well-being after conducting the regression analysis. Conclusion: The results from the current study contribute to a growing body of literature examining relationships between several factors and well-being outcomes for community-dwelling older adults. Data from the current study provide substantial insight on how health status, participation, and SDOH indicators can be used in future research to explore these relationships, and identify populations at risk for occupational justice or health inequities. Future research is warranted to validate measures and indicators of SDOH to further explore their relationships with health and well-being outcomes using national data sets.