Digital Commons Network^™

Aging Of Florida Blue Crabs, Callinectes Sapidus, Through The Biochemical Extraction Of Lipofuscin, Claire Elizabeth Crowley

USF Tampa Graduate Theses and Dissertations

The blue crab, Callinectes sapidus, represents an ecologically and economically important component of marine and estuarine ecosystems. In Florida, blue crab landings accounted for $9.6 million dollars during the 2010 fishing season. Accurate stock assessments for this valuable fishery are essential. Age is a critical biological component of accurate stock assessments; however, blue crabs and other crustaceans are especially difficult to age because of the complex nature of discrete growth. Biochemical extraction of an aging pigment, lipofuscin, was developed using blue crab eyestalks. The current study investigated the effects of freezing preservation on lipofuscin extracts and examined whether the …

Optimal Control Of Human Running, Ross Herbert Miller

Open Access Dissertations

Humans generally use two modes of locomotion as adults. At slow speeds we walk, and at fast speeds we run. To perform either gait, we use our muscles. The central questions in this dissertation were: (1) Why do humans run the way they do, and (2) How do the mechanical properties of muscle influence running performance? Optimal control simulations of running were generated using a bipedal forward dynamics model of the human musculoskeletal system. Simulations of running and sprinting were posed as two-point boundary value problems where the muscle excitation signals were optimized to maximize an optimality criterion. In the …

Alternations In The Splenic Marginal Zone With Age, Shirin Z. Birjandi

Dissertations

Splenic marginal zones are architecturally organized to generate a rapid response against blood- borne antigens entering the spleen. The marginal zone is a distinct anatomical micro-environment whose main components include the marginal zone macrophages, the marginal zone B cells, the marginal zone sinus, and the metallophilic macrophages. Marginal zone macrophages, in partnership with marginal zone B cells, are particularly important in host defense against T-independent pathogens and are crucial for the prevention of diseases such as Streptococcus pneumonia. It has been widely reported that with the advancement of age there is a higher rate of mortality as a result of …

The Role Of Nogo-A In Memory And Neuronal Plasticity In The Aged Rodent Brain, Rebecca Lynn Gillani

Dissertations

The long-term effects of stroke often include cognitive impairments, but other than cognitive rehabilitation, which is often not fully successful, there is no intervention to treat cognitive impairments in stroke survivors. Our laboratory has previously shown that immunotherapy directed against the Nogo-A protein, which is enriched on oligodendrocytes, improves recovery of skilled forelimb sensorimotor function in adult and aged rats after an ischemic stroke lesion to the sensorimotor cortex. Furthermore, this recovery was correlated with axonal sprouting from intact pathways to denervated areas, as well as dendritic sprouting and increased dendritic spine density in the contralateral sensorimotor cortex. In the …

Gene Expression Regulators Lin-11 And Let-711, In Modulating The Rate Of Aging And Lifespan, In C. Elegans., Tseten Yeshi Jamling

University of Kentucky Doctoral Dissertations

lin-11 and let-711 are early-developmental gene expression regulators with no previously known roles in aging regulation. Yet, they show strong aging-correlated expression profiles (Lund, Tedesco et al. 2002). lin-11 is strongly upregulated in very old worm populations, and let-711 is progressively downregulated in aging worm populations. Microarray studies were performed to identify their genome-wide targets, which were then subjected to further lifespan and genetic analysis to investigate their role in C. elegans aging.

The results indicate that the target pools of both lin-11 and let-711 are enriched for aging genes, since a significant number of tested genes increased lifespan. This …

Role Of Pi3k-Akt Pathway In The Age Associated Decline In Tlr Mediated Activation Of Innate And Adaptive Immune Responses, Mosoka Papa Fallah

University of Kentucky Doctoral Dissertations

Immunosenescence results in reduced immune response to infections with Streptococcus pneumoniae as well as to pneumococcal polysaccharide vaccines. The antibody response to the capsular polysaccharide (CPS) provides protection against S. pneumoniae infection. CPS immunoresponse is T cell independent and needs the macrophage-derived cytokines such as IL-12, IL-6 and IL-1β to elicit an antibody response. We showed a cytokine dysregulation, i.e. a decrease in IL-12, IL-6 and TNF-α but an increase in IL-10, in the aged (18-24 months old comparable to >65 years in human) compared to young adult mouse (8-12 weeks less than 65 years old) splenic macrophages (SM) or …