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The Effect Of Spinal Cord Injury On Vagal Afferents., April N. Herrity
The Effect Of Spinal Cord Injury On Vagal Afferents., April N. Herrity
Electronic Theses and Dissertations
Spinal cord injury (SCI) is a significant public health concern that leaves patients with a multitude of life-long disabilities. Major complications of SCI apart from paralysis, include deficits in bladder and bowel function. Lower urinary tract dysfunction continues to remain a top priority issue affecting quality of life for this population. The majority of visceral organs receive a dual sensory innervation from both spinal nerves as well as the vagus nerve. Following SCI, the vagus nerve is a potential pathway through which information from regions below the level of a spinal injury can travel directly to the brainstem, bypassing the …
Development Of Models For The Study Of The Molecular Mechanisms Of Host Restriction And Adaptation Of Hantaviruses., Ryan Carroll Mcallister 1988-
Development Of Models For The Study Of The Molecular Mechanisms Of Host Restriction And Adaptation Of Hantaviruses., Ryan Carroll Mcallister 1988-
Electronic Theses and Dissertations
Hantaviruses, family Bunyaviridae, are present throughout the globe in a variety of mouse, rat, mole, vole, shrew, or bat species. Hantaviruses persist for the lifetime of the animal reservoir, while causing no signs or symptoms of disease. Only the rodent-borne hantaviruses cause disease in humans. In contrast, a “spillover” infection of a hantavirus into a nonreservoir rodent species results in an asymptomatic acute infection. We and others in the field are interested in understanding the biology of these virus-host interactions and mechanisms that underlie these three very different outcomes. The second chapter of my thesis focused on probing the intrahost …
Craniodental Anatomy Of A New Late Cretaceous Multituberculate Mammal From Udan Sayr, Mongolia., Amir Subhash Sheth
Craniodental Anatomy Of A New Late Cretaceous Multituberculate Mammal From Udan Sayr, Mongolia., Amir Subhash Sheth
Electronic Theses and Dissertations
Multituberculates were the longest-lived group of early mammals, with a nearly worldwide distribution, and a temporal range from the Middle Jurassic to the Late Eocene. Multituberculates are typically represented by isolated teeth and jaw fragments; however, several localities in Mongolia revealed abundant, well-preserved multituberculate skulls and partial skeletons from the Late Cretaceous. This study is centered on two specimens of a new multituberculate taxon from a locality in the Gobi desert, Udan Sayr. Included is a (1) bone-by-bone description of the cranial and mandibular elements, as well as the dental features of both specimens, PSS-MAE 141 (holotype) and PSS-MAE 142, …
Effects Of Passive Immobilization On Locomotor Recovery After Spinal Cord Injury In Adult Rats., Kelsey Lee Stipp
Effects Of Passive Immobilization On Locomotor Recovery After Spinal Cord Injury In Adult Rats., Kelsey Lee Stipp
Electronic Theses and Dissertations
Background: Spontaneous locomotor recovery in spinal rats has been attributed to animals moving freely in-cage. Environmental enrichment has been shown to increase in-cage movement and functional recovery subsequently. Anxiety has been shown to decrease overnight activity in rats. Methods: Rats were double-housed in medium cages (MC) or single-housed in tiny sized cages (TC). Slotted dividers allowed for partial isolation in TC. Overnight activity was monitored bi-weekly. The open field test and BBB’s were taken weekly. Gait analysis was performed at weeks six and eight. Results: MC showed higher overnight activity and improved gait overtime. No differences were found in BBB …
Bdnf Maintains Adult Taste Innervation And Is Required For Taste Nerve Regeneration After Injury., Lingbin Meng
Bdnf Maintains Adult Taste Innervation And Is Required For Taste Nerve Regeneration After Injury., Lingbin Meng
Electronic Theses and Dissertations
Brain derived neurotropic factor (BDNF) is required for the gustatory neuron survival,target innervation, and taste bud maintenance during development. However, whether BDNF has any function in the adult gustatory system in normal conditions or after nerve injury is unclear. To address these issues, I inducibly removed BDNF in all cells expressing BDNF in adult mice. In the experimental animals, Bdnf expression decreased to 5% of control mice in the lingual epithelium and geniculate ganglion (p< 0.01) at both two weeks and ten weeks after tamoxifen administration. I found no effect on taste bud morphology at four weeks following Bdnf gene deletion. However, ten weeks following Bdnf gene deletion, P2X3-positive and TUJ1-positive gustatory innervation to individual taste buds was reduced by nearly half (each with p < 0.01) and both taste bud volume and taste cell number decreased 30% (each with p< 0.01). These experiments demonstrate that BDNF is required for maintenance of normal levels of taste innervation and normal taste bud morphology in adulthood. In addition, taste cells expressing PLCß2 (phospholipase C ß2), a marker for taste cells that respond to sweet, bitter and umami, did not decrease after Bdnf gene deletion in the adult. Thus, the missing taste cells are of another type. This indicates that taste cell loss is not uniform across the various taste cell types, even if nearly all taste cell types receive the P2X3 and TUJ1 innervation. Since BDNF is required for initial innervation of the taste system and supports taste bud innervation and size in adulthood, it could also be required for nerve reinnervation after injury. To determine if Bdnf is still expressed following nerve section, the chorda tympani nerve (taste nerve) was sectioned and Bdnf level was detected with Real Time RT-PCR. Bdnf continued to be expressed at normal levels from two days to two months post-surgery in both geniculate ganglion and tongue epithelium. Therefore, BDNF could be involved with chorda tympani regeneration. To determine if this was the case, the Bdnf gene was deleted in adult inducible transgenic mice (under the control of a Ubiquitin promoter) two weeks before chorda tympani nerve section. Taste bud number was reduced by half in all genotypes at two weeks post-surgery (p < 0.01). For the remaining taste buds, gustatory innervation was nearly gone with only a little innervation from the trigeminal nerve remaining in the taste bud (p < 0.01). Taste bud volume (p < 0.01) and taste cell number (p< 0.01) were reduced by half for both control and experimental genotypes. Eight weeks post-surgery, taste bud number recovered in mice without Bdnf gene deletion, but did not recover in mice following Bdnf gene deletion (p < 0.01). Gustatory nerve innervation returned in 70% of the taste buds in control mice (p< 0.01). For those reinnervated taste buds, both taste bud volume and taste cell number increased to normal levels. However, in mice lacking the Bdnf gene, gustatory fibers only reinnervated 7.8% of the taste buds (p < 0.01); for most uninnervated taste buds, both taste bud volume and taste cell number remained small. These experiments demonstrate that BDNF is crucial for promoting regeneration of gustatory nerve fibers in adulthood. Following gustatory nerve section, considerable adult plasticity has been observed on the contralateral side including enlarged taste buds with more cells (Guagliardo and Hill, 2007). To determine if this anatomical change was associated with alter Bdnf expression. I examined Bdnf level in the geniculate ganglion and tongue epithelium on the contralateral side following chorda tympani nerve section. Results showed Bdnf expression increased two fold at two weeks post-surgery in geniculate ganglion on the contralateral side (p < 0.05), indicating BDNF may involve with the observed plastic changes. To determine if the increase in taste bud size was associated with increased innervation and/or regulated by BDNF, the Bdnf gene was then deleted in inducible knockout mice before nerve surgery, and taste bud size and amount of innervation were measured on the contralateral side. The results showed taste bud volume, taste cell number and a marker for nerve fibers all increased on the contralateral side in mice without Bdnf gene deletion at eight weeks post-surgery. This indicates that larger taste buds could be supported by increased TUJ1 positive fibers from trigeminal nerve. In addition, in mice lacking Bdnf, taste bud volume, taste cell number and innervation did not increase on the contralateral side after surgery, which indicates that Bdnf may contribute to larger taste buds on the contralateral side following nerve section by supporting increased innervation to the larger taste buds.
Interactions Between Human Neutrophils And Mycobacterium Smegmatis : A Comparative General Analysis., Irina Miralda
Interactions Between Human Neutrophils And Mycobacterium Smegmatis : A Comparative General Analysis., Irina Miralda
College of Arts & Sciences Senior Honors Theses
Mycobacteria smegmatis is an abundant soil and water inhabitant with which humans are continuously in contact. Despite the fact that it is typically considered non-‐pathogenic, a few rare cases of M. smegmatis-‐caused infections have been reported and it has been shown that M. smegmatis is able to modulate inflammatory responses in macrophages. Neutrophils are the innate immune system’s first line of centralized defense against invading microbes, especially the frequently encountered M. smegmatis. However, very little information is known of the mechanism by which neutrophils eliminate environmental bacteria. In this study, the hypothesis that M. smegmatis regulates neutrophil functional responses, and …