The purpose of this study was to establish the perceived caregiving effects among thirty Cuban-born individuals caring for elderly relatives and the relationship of these effects with acculturation. Most common difficulties were lack of private time, or social life, and decreased emotional and physical health. Satisfactions were mostly derived from fostering the elders' welfare. A strong positive relationship was found between caregivers' difficulties and stability of the caregiving dyad (r= - 0.642, p< .001). Caregivers involved in more unstable caregiver-care receiver dyads had more stress associated with caregiving difficulties. The acculturation factors of language, electronic media, and social relations, and the stability of the caregiving dyad accounted for 54 percent of the variation in caregivers' difficulties (p< .001) but only 21 percent of the variation of caregivers' satisfaction (p<.221). These findings provided preliminary data of caregiving characteristics among Cuban-Americans and the importance of including acculturation in studies involving minorities.

The purpose of this dissertation was to investigate the influences of auditory information provided by the cochlear implant (CI) on the readings skills of children born with profound deafness. I investigated the relationship of access to the sound signal provided by the CI on a constellation of skills related to word-reading. In a preliminary study, I examined the relationship between the early speech production and perception skills of 72 CI users on later reading skills. Using regression analysis, I found I could explain 59% of the variance of later reading skills by early speech perception and production performance. Secondly, I examined the phonological processing skills of 29 children with prelingual, profound hearing loss with at least 4 years of CI experience. I compared this performance with 29 children with normal hearing, matched with regard to word-reading ability and Socio-Economic-Status. I also compared speech production and perception skills with phonological processing and reading skills. Results revealed that children with CIs were able to complete tasks measuring phonological processing, but there were performance differences between the two groups. Although the children with CIs had mean standard reading achievement standard scores that were about 12 points lower than the children with normal hearing, the mean standard scores for both groups was within the normal range. Finally, a regression analysis revealed that the Phonological Processing skills accounted for 50%, and 75% of the variance in word and paragraph reading scores for all the children. In conclusion early speech perception and production skills of children with profound hearing loss who receive CIs predict future reading achievement skills. Better early speech perception and production skills result in higher reading achievement. Furthermore, the early access to sound helps to build better phonological processing skills, which is one of the likely contributors to eventual reading success. Thus, it is reasonable, possible and important to assess the early speech production perception and subsequent phonological processing in children with profound hearing loss who receive CIs.

Background Injuries are the leading cause of death in the United States for children between the ages of 1 and 19 years. Weekend hospital admission has been associated with poor outcomes and higher mortality rates for a variety of diseases. We examined the impact of weekend versus weekday admission on in-hospital morbidity and case-fatality rates for pediatric trauma patients. Methods We performed a cross-sectional analysis on the 2016 Kids’ Inpatient Database. The study population included pediatric trauma patients under the age of 19 years which were stratified by weekend vs weekday admission. Weightings were used to produce national estimates. Multiple logistic regression analyses were performed to assess the odds of in-hospital complications and death after adjusting for a variety of potentially confounding demographic and clinical factors. Results Patients admitted on a weekend were older, more frequently male, White, and privately insured. Weekend admissions had a higher Injury Severity Score (6.7 vs 5.4, p<0.001), as well as higher rate of intensive care unit (ICU) admission (8.5% vs 7.1%, p<0.001) and in-hospital case-fatality rate (1.3% vs 1.1%, p=0.003), but lower rate of in-hospital complications (6.1% vs 6.8%, p<0.001). Unadjusted logistic regression demonstrated that weekend admission was associated with higher odds of in-hospital death as compared to weekday admission (odds ratio 1.20, 95% confidence interval [CI] 1.07 – 1.35), but in the multivariable adjusted model this was no longer statistically significant (adjusted odds ratio [aOR] 1.06, 95% CI 0.94 – 1.20). Weekend admission was associated with lower odds of in-hospital complications (aOR 0.90, 95% CI 0.86 - 0.95), but higher odds of ICU admission (aOR 1.12, 95% CI 1.06 – 1.18). Conclusions Weekend admission in pediatric trauma is associated with higher odds of ICU admission. There does not appear to be an association between weekend admission and odds of in-hospital death, however it may be associated with lower odds of in-hospital complications.

Respiratory motion poses significant problems in the radiotherapy of tumors located at sites (lung, liver, pancreas, breast) that are affected by such motion. Effects of respiratory motion on the different stages of the radiotherapy process (imaging, treatment planning and treatment delivery), has formed the focus of significant research over the last decade. Results from such research have revealed that respiratory motion affects the instantaneous position of almost all structures in the thorax and abdomen to different degrees based on their corresponding anatomic location and muscular attachments. As an example, diaphragm motion was found to be of the order of 1.5 cm, predominantly in the superior-inferior (SI) direction during normal breathing. This indicates a similar magnitude of motion for tumors located in the lower lobes of the lung and in the abdomen.The conventional method of accounting for such motion is to add a margin (based on an estimate of the expected range of organ motion) around the clinical target volume (CTV) that is delineated from the image data. This margin also includes errors due beam-bony anatomy alignment during radiation delivery and errors in patient position between simulation and subsequent treatment delivery sessions. Such a margin estimate may or may not encompass the "current" extent of motion exhibited by the tumor, resulting in either a higher dose to the surrounding normal tissue or a potential cold spot in the tumor volume. Several clinical studies have reported the existence of a direct relationship between the reduction in mean dose to the lung and the incidence of radiation induced pneumonitis. Therefore, subjecting additional normal lung tissue to high dose radiation by adding large margins based on organ motion estimates may result in an increased risk of radiation induced lung injury.Monitoring and accounting for respiratory motion can however potentate a reduction in the amount of normal tissue that receives high dose radiation, thereby decreasing the probability of normal tissue complication and also increasing the possibility for dose escalation to the actual tumor volume. The management (monitoring and accounting) of respiratory motion during radiation oncology forms the primary theme of this dissertation.Specific aims of this thesis dissertation include (a) identifying the deleterious effects of respiratory motion on conventional radiation therapy techniques (b) examining the different solutions that have been proposed to counter the deleterious effects of respiratory motion during radiotherapy (c) summarizing the relevant work conducted at our institution as part of this thesis in addressing the issue of respiratory motion and (d) visualizing the future direction of research in the management of respiratory motion in radiation oncology.Among the various techniques available to manage respiratory motion in radiation oncology such as respiratory gated and breath hold based radiotherapy, our research initially focused on respiratory gated radiotherapy, employing a commercially available external marker based real time position monitoring system. Multiple session recordings of simultaneous diaphragm motion and external marker motion revealed a consistent linear relationship between the two signals indicating that the external marker motion (along the anterior-posterior (AP) direction) could be used as a "surrogate" for motion of internal anatomy (along the SI direction). The predictability of diaphragm motion based on such external marker motion both within and between treatment sessions was also determined to be of the order of 0.1 cm.Analysis of the parameters that affected the accuracy and efficacy of respiratory gated radiotherapy revealed a direct relationship between the amount of residual motion and the width of the "gate" window. It also followed therefore that a trade-off existed between the width of the "gate" and the accuracy of gated treatments and also the overall "Beam ON" time. Further, gating during exhale was found to be more reproducible than gating during inhale. Although, it was evident that a reduction in the width of the "gate" implied a reduction in the margins added around the clinical target volume (CTV), such a reduction was limited by setup error.A study of the potential gains that could be derived from respiratory gating (based on motion phantom experimental set up) indicated a potential CTV-PTV margin reduction of 0.2-1.1 cm while employing gating alone in combination with an electronic portal imaging device, thus decreasing the amount of healthy tissue receiving radiation. In addition, gating also improved the quality of images obtained during simulation by reducing the amount of motion artifacts that are typically seen during conventional spiral CT imaging.Imparting some form of training was hypothesized to better enable patients to breathe in a reproducible fashion, which was further thought to increase the accuracy and efficacy of gated radiotherapy, especially when the "gate" was set close to the inhale portion of the breathing cycle. An analysis of breathing patterns recorded from five patients over several sessions under conditions of normal quiet breathing, breathing with audio instructions and breathing with visual feedback indicated that training improved the reproducibility of amplitude or frequency of patient breathing cycles.An initial exploration into respiration synchronized radiotherapy was thought to facilitate realization of reduced margins without having to hold the radiation beam delivery during a breathing cycle (as is the case with gating). A feasibility study based on superimposition of respiratory motion of a tumor (simulated by a sinusoidal motion oscillator) onto the initial beam aperture as formed by the multileaf collimator (MLC) revealed that tumor dose measurements obtained with such a set up were equivalent to those delivered to a static tumor by a static beam.Finally, a feasibility study for a method to acquire respiration synchronized images of a motion phantom and a patient (in order to perform respiration synchronized treatment planning and delivery) yielded success in the form of a 4D CT data set with reduced motion artifacts.In summary, respiratory gated radiotherapy and respiration synchronized are both viable approaches to account for respiratory motion during radiotherapy. While respiratory gated radiotherapy has been successfully implemented in some centers, several technical advances are required to enable similar success in the implementation of respiration synchronized radiotherapy. However, the potential clinical gains that can be obtained from either of the above approaches and their relative contributions to margin reduction will determine their future applicability as routine treatment procedures.

Cannabinoids, such as the marijuana derivative Δ9-THC, are known to have CBl receptor-mediated anticonvulsant effects in several animal models of seizures and epilepsy, including the rat pilocarpine model of acquired epilepsy. However, the distribution of CBl receptor expression and function in brains of epileptic rats has not been characterized. Therefore, this dissertation was initiated to evaluate the effect of epileptogenesis on the distribution and function of the endogenous CBI receptor system in the rat pilocarpine model, a well-established model of acquired temporal lobe epilepsy. Using immunohistochemistry, we demonstrated that chronically epileptic rats exhibit a unique, long-term, and specific redistribution of hippocampal CBl receptors when compared to controls, with concurrent layer-specific increases and decreases in CBl receptor expression within the hippocampus. In addition, studies in this dissertation demonstrated using [3H] WIN55,212-2 autoradiography and agonist-stimulated [35S]GTPγS autoradiography that this CBl receptor-specific reorganization results in corresponding functional changes manifested by alterations in CBl receptor binding and G-protein activation. These regionally selective changes were dependent on NMDA receptor activation during the initial insult of pilocarpine-induced status epilepticus (SE), and were independent of seizure suppression produced with phenobarbital administration in epileptic rats. Furthermore, time-course studies utilizing these techniques demonstrate that within a week following SE, a widespread loss of CBl receptor expression and function occurs throughout the hippocampus. The subsequent redistribution of CBl receptors that occurs temporally correlates with the emergence of spontaneous recurrent seizures, and is still observed up to 1 year following SE. Overall, the reorganization of cannabinoid receptors in epilepsy implicates the endocannabinoid system in modulating neuroexcitability in the epileptic state. This CBl receptor redistribution represents an essentially permanent neuronal plasticity change associated with epileptogenesis, and could account for the anticonvulsant effect of cannabinoids observed in this model.

Tonic arterial smooth muscle can produce strong contractions indefinitely by formation of slowly cycling crossbridges (latchbridges) that maintain force at a high energy economy. To fully understand the uniqueness of mechanisms regulating tonic arterial contraction, comparisons have been made to phasic visceral smooth muscles that do not sustain high forces. This study explored mechanisms of force maintenance in a phasic artery by comparing KCl-induced contractions in the tonic, femoral artery (FA) and its primary branch, the phasic saphenous artery (SA). KCl rapidly (5 N/m2) and [ca2+]i (250 nM) in FA and SA. By 10 min, [ca2+]i declined to 175 nM in both tissues but stress was sustained in FA (1.3 x 105N/m2) and reduced by 40% in SA (0.8 x l05 N/m2). Reduced tonic stress correlated with reduced myosin light chain (MLC) phosphorylation in SA (28% vs. 42% in FA). SA expressed more MLC phosphatase than FA, and permeabilized (β-escin) SA relaxed more rapidly than FA in the presence of MLC kinase blockade, suggesting that MLC phosphatase activity in SA was greater than that in FA. The reduction in MLC phosphorylation in SA was insufficient to account for reduced tonic force (latchbridge model), and SA expressed more "fast" myosin isoforms than did FA. Cytochalasin-D reduced force-maintenance more in FA than SA. These data support the hypothesis that strong force-maintenance is absent in SA because expressed motor proteins do not support latchbridge formation, and because actin polymerization is not stimulated.

Obesity is a known risk factor for preeclampsia, but the reason for this risk is unknown. We sought to demonstrate how obese individuals are predisposed to preeclampsia by mechanisms involving inflammation and the innate immune system. First, we used immunohistochemical studies to identify neutrophil infiltration, NF-κB activation and COX-2 expression in vascular tissue of obese women. We then demonstrated similar neutrophil infiltration and vascular inflammation in preeclamptic women.We used in vitro experiments to test if neutrophils and their products, reactive oxygen species (ROS) and tumor necrosis factor-alpha (TNFα) can activate NF-κB and cause expression of its inflammatory products, COX-2, thromboxane (TX) and IL-8. Co-culture of neutrophils or treatments of ROS or TNFα caused activation of NF-κB and expression of COX-2, TX and IL-8 in vascular smooth muscle cells.This investigation is the first to demonstrate activation of NF-κB and expression of COX-2 coincident with neutrophil infiltration in systemic vascular tissue of obese and preeclamptic women. These data implicate neutrophils as a cause of vascular inflammation. They also suggest that if an obese woman's vasculature was in an inflamed state she is at increased risk for preeclampsia when exposed to the additional burden of oxidative stress and neutrophil activation imposed by the placenta, causing her to develop vascular dysfunction and clinical symptoms of PE (hypertension and edema).

The purpose of this study was to determine the effects of needle play in reducing pre-school children's anxiety concerning injections. The Pre-school Observational Scale of Anxiety was used to measure the degree of anxiety experienced by the children. The hypothesis stated that there would be a significant decrease in anxiety of pre-school children who participated in needle play as compared with the anxiety scores of pre-school children who did not participate in needle play.The sample consisted of 20 pre-school children who were receiving routine health care and injections for immunizations or PPDs (purified protein derivative) at a county health department in the southeast. After obtaining informed consent, children were randomly assigned to either a control group (n = 10) or experimental group (n = 10). The control group was involved in putting together a puzzle with the investigator prior to their injection. The experimental group participated in needle play with the investigator prior to their injection. The Pre-school Observational Scale of Anxiety (POSA) which specifies behavioral indicators of anxiety in children was used on all subjects immediately prior to the actual needle penetration and a score was given to each subject.The scores on the Pre-school Observational Scale of Anxiety showed no statistically significant difference between the control group and the experimental group when analyzed using the Mann-Whitney U Test. On the basis of these findings, the hypothesis that pre-school children who participate in needle play immediately prior to receiving an injection would show a significant decrease in anxiety when compared to pre-school children who did not-participate in needle play prior to an injection was not accepted.

There are no reliable tools that evaluate pain in adult critical care patients who cannot communicate as a result of sedation or illness. This was an observational study in which postoperative cardiothoracic intensive care patients were assessed for pain using both the newly devised Corbett Pain Scale (CPS) and the Numerical Pain Scale (NPS). The CPS was evaluated for content validity, criterion validity, construct validity, test re-test reliability and internal consistency. Thirteen male and seven female patients (n=20) were enrolled and underwent a maximum of five pain assessments each. The mean total scores of the CPS (.740, SD+1.03) and the NRS (.000, SD+1.00) were compared using a paired t-test. No significant differences were found. There was poor internal consistency (-.1225) and there was insignificant correlation between the scales. Pain measurement of sedated, non-communicative patients continues to be problematic.

A large percentage of Americans own pets which may impact their health. This study examines pet ownership’s effect on well being in older adults looking at race/ethnicity. A sample of 6,565 older adults (>60) was selected from the Third National Health and Nutrition Survey. Pet owners comprised 28.3% of the sample. The theories of symbolic interaction and social integration were used to examine pet ownership’s effect on physical components of well-being. The descriptive results showed statistically significant differences in age, education, income, and marital status between pet owners and non-pet owners. Pet owners were younger, more educate, higher income and married. Similar results were found for Caucasians, African Americans and Mexican Americans. Logistic regression for the entire sample revealed pet owners were more likely to have a positive self perception of health, normal blood pressure, improved function, less chronic conditions, improved function and more falls. Multiple regression revealed pet owners had more hospital stays, but fewer physician visits and nursing home stays than non-pet owners. When examined by race/ethnicity differences were found between pet owners and non-pet owners that differed from the general sample results. This research revealed that pets overall positively impact their owners’ health but it appears to differ based on race/ethnicity. Further research is needed on pet ownership’s effect on older adults specifically in regards to race.