Introduction: The presence of an endotracheal tube (ETT) increases the risk for microaspiration of secretions around the ETT. Biomarkers of pepsin and salivary amylase may be used to identify microaspiration in intubated patients because of their naturally occurring presence in the stomach or oral cavity and non-occurrence in the respiratory tract. Microaspiration may be difficult to detect until pulmonary complications, such as lung injury or infection, occur. This study assessed the presence of pepsin and salivary amylase in oral and tracheal secretions of ventilated adults. Method(s): This is a secondary analysis of data collected from 11 critically ill, adult patients on mechanical ventilation (MV) enrolled in a study to identify cues for ETT suctioning. Two paired samples of oral and tracheal secretions were suctioned when clinically indicated. Tracheal secretions were suctioned with a closed system, and oral secretions were obtained with an oropharyngeal catheter. Specimens were analyzed for total pepsin, pepsin A, pepsin C, and salivary amylase according to established assays. Results: Of 11 subjects, the majority were men (n=8), on enteral feedings (n=9) via a feeding tube placed in the stomach (n=7), and intubated with a continuous subglottic suction ETT (n=8). Median values: age, 62 years; duration of MV, 5.5 days; ETT cuff pressure 24 cm H2O; head of bed, 30degrees]. Pepsin was in measured in both oral (30.5 ng/mL; n=8) and tracheal secretions (11.1 ng/mL; n=7); Similar findings were noted for pepsin A (oral 14.7 ng/mL, n=7; sputum 7.4 ng/mL, n=6) and pepsin C (oral 14.7, n=7; tracheal 7.4, n=6). Salivary amylase (mean micro]mol/min/mL) was present in all oral secretions (359.8) and in the sputum of 6 subjects (1.8). Discussion & Conclusions: The majority of intubated patients on MV had both pepsin and salivary amylase in their sputum, likely due to microaspiration of secretions.; This finding suggests greater efforts are needed to reduce patients' risk. Ongoing strategies to prevent gastric reflux are important such as head of bed elevation and monitoring residuals. Presence of salivary amylase within tracheal secretions may indicate a need for more frequent oropharyngeal suctioning as part of routine care of intubated patients. Analysis shows no variations of the presence of pepsin or salivary amylase in relation to feeding tube placement or type of ETT. Generalizability is limited by the small sample size.

The aspiration of oral and gastric substances is a well-known risk for ventilator associated pneumonia (VAP) in the intubated, mechanically ventilated (MV), patient of the intensive care unit (ICU) population. The gastric biomarker pepsin and the oral biomarker salivary amylase have been identified as evidence of aspiration prior to the manifestation of acute pulmonary illness. In an effort to decrease the risk for aspiration, several evidence based nursing practices are in place. Actions include 30 degree head of the bed positioning, oral care, suctioning, and circuit change interval protocols, as well as the administration of medication with the objective of reducing acid reflux. Additional recommendations concern the type of endotracheal tube (ETT) used to ventilate the intubated patient. The continuous subglottic suctioning endotracheal tube (CSS-ETT) features an additional port which continually suctions secretions that accumulate above the inflated endotracheal cuff. Patients with standard endotracheal tubes (S-ETT) receive manual, as needed suctioning of accumulated secretions in the mouth and the oropharynx per agency protocol. Research of the critical care population has demonstrated a decreased instance of VAP using CSS-ETT as compared to S-ETT utilization. This study sought to compare the incidence of the biomarkers pepsin and salivary amylase in the suctioned oral and tracheal secretions of patients with S-ETT compared to patients with CSS-ETT. Part of the protocol of a descriptive, comparative study of the clinical indicators for suctioning established the collection of the paired suctioned oral and tracheal aspirates. Those collected aspirates were analyzed for a pilot study of pepsin and amylase analysis. This study compares the incidence of aspirates in oral and tracheal secretions by endotracheal tube type.; The intention of this study was that it would assist in demonstrating beneficial aspects of the selection of the CSS-ETT. It is considered that further investigation with a larger population group could add statistical significance.; Tracheal aspirates were obtained with a closed tracheal suction device while oral secretions were obtained with a suction catheter designed to reach the oropharynx. Biomarkers assayed were the gastric marker pepsin and the oropharyngeal marker salivary amylase. Assays of pepsin and salivary amylase were performed using standard procedures in a specialty diagnostic laboratory. Specimens were obtained from 11 subjects: 8 male and 3 female. The majority were Caucasian (n=9), had a CSS-ETT (n=8), were on mechanical ventilation in the synchronized intermittent mandatory ventilation mode, and on tube feedings (n=9) located in the stomach (n=7). The mean age was 56 years. Feeding tubes were placed in 9 patients, and the majority of the tubes were Dobbhoff. Pepsin was found in the oral secretions of 62.5% (n = 5) of the CSS-ETT subjects, while 50.0% (n = 4) had pepsin in the tracheal aspirate. Pepsin was found in the oral secretions of 66.7% (n = 2) of the S-ETT subjects, and 66.7% (n = 2) had pepsin in their tracheal aspirate. All subjects of both groups (n = 11) had oral salivary amylase detected. Salivary amylase was detected in the tracheal aspirate of 100% (n = 3) of the S-ETT subjects versus 62.5% (n = 5) in CSS-ETT group. Based on the results of this study, there was a reduction in the number of subjects who had oral compared to tracheal aspirate pepsin in the CSS-ETT group (n = 5 oral versus n = 4 tracheal) tube type. The S-ETT group had equal number of subjects with oral (n = 2) and tracheal pepsin detected (n = 2). However, the results when comparing the S-ETT and the CSS-ETT groups were not statistically significant (p = 0.898 pepsin oral and 0.621 tracheal pepsin). There may be clinical significance. It appears that the CSS-ETT was beneficial in that group; two fewer subjects had pepsin in their tracheal aspirate (n = 5 oral versus n = 4 tracheal aspirate pepsin).

Emotion processing and regulatory deficits have been well established in individuals diagnosed with bipolar disorder (BD). Both structural and functional neural deficits have been associated with the presence of psychiatric symptoms in BD. In Chapter 2, we reviewed cortical thickness deficits found in patients with BD. It is unclear however, how early these deficits appear; whether they contribute to risk, or whether these deficits develop as a consequence of the onset of symptoms. To address this, many researchers have turned to high-risk offspring populations. These high-risk offspring are at much greater risk of developing BD by virtue of having a parent diagnosed with BD. Moreover, the presence of anxiety, depression or ADHD related symptoms in this population suggest these children are at even greater risk to develop BD. By comparing high-risk offspring with and without the symptoms can help to elicudate neural correlates associated with risk and resilience for BD. It was the aim of this thesis research to investigate the behavioural, structural and functional correlates of risk. Specifically, presented in this thesis, we compared the gray matter integrity, through volume (Chapter 3) and cortical thickness (Chapter 4) techniques, in symptomatic and asymptomatic high-risk offspring to healthy children of healthy parents. We also compared the ability of these offspring to perform an emotion-labelling task (Chapter 5) and engage in emotional conflict monitoring and conflict adaptation during an fMRI scan (Chapter 6). Altogether, our results provide evidence for the presence of gray matter volume, emotion labelling, and conflict monitoring and conflict adaptation functional deficits in high-risk offspring compared to healthy children of healthy parents. With the exception of cortical thickness, we found that the deficits between symptomatic and asymptomatic high-risk offspring were comparable. This suggests that behavioural, structural and functional deficits may reflect neural correlates of risk and are not associated with the presence of symptoms. / Thesis / Doctor of Philosophy (PhD)

Objective: Alcohol use disorder (AUD) remains a leading cause of worldwide mortality and morbidity. The development of neuroanatomical biomarkers offers the potential of novel clinical indicators to guide prevention, early diagnosis, and treatment. Methods: In 76 participants with DSM-5 diagnosed AUD (Mage = 35.75; 51.3% female) and 79 controls (Mage = 34.71; 59.5% female), we utilized magnetic resonance imaging (MRI) to investigate four novel measures: hippocampal and amygdalar subregion volumes, sulcal morphology (SM), and fractal dimensionality (FD). MRI processing, segmentation, and SM and FD quantification were completed using FreeSurfer v6.0 and v7.0, and MATLAB toolboxes, respectively. A significance value of p < .05 was employed for analysis and sex, age, and intracranial volume were included as covariates. Results: Volumes of the right presubiculum, subiculum, and molecular layer head; left lateral and accessory basal nuclei; and corticoamygdaloid transition area were significantly lower in AUD participants relative to healthy controls. Widths of the left occipito-temporal, right middle occipital and lunate, and right marginal part of the cingulate sulci and depth of the post-central sulci were significantly increased in AUD participants relative to controls. Finally, decreased left caudate, left thalamus, right putamen and right pallidum FD and greater inferior lateral and third ventricle FD were observed in AUD participants relative to controls. Each novel measure’s reliability was assessed using test-retest data from the Human Connectome Project and indicated high reliability with median intraclass correlations of .93, .91, .88, and .93 for the hippocampal subfields, amygdalar nuclei, SM, and FD, respectively. Conclusion: These results indicate selectively decreased hippocampal and amygdala subregion volume, increased sulcal depth and width, and differences in FD as promising neuroanatomical biomarkers for AUD. / Thesis / Master of Health Sciences (MSc)

No description available.

Objective: To evaluate whether abnormal concentrations in cardiac and inflammatory biomarkers could predict reductions in left ventricular ejection fraction (LVEF) for cancer patients undergoing curative treatment. Materials and Methods: Longitudinal testing was performed for high-sensitivity cardiac troponin I (hs-cTnI), N-terminal pro-B-type natriuretic peptide (NT-proBNP), heart-type fatty acid binding protein (H-FABP) and C-reactive protein (CRP) in HER2+ breast cancer (BC) patients receiving adjuvant trastuzumab treatment (n=22) and in lymphoma patients treated with radiotherapy (n=4). Sex-specific and overall upper limit of normal (ULN) cutoffs were used to identify abnormal results with a reduction in LVEF (<50% and decrease of ≥10% from baseline) indicative of cardiotoxicity. A secondary analysis was performed on the BC patients with normal LVEFs (n=12 with baseline prior to chemotherapy through to 6-months on trastuzumab) with 15 blood collections spaced between 6- and 254-days post-baseline LVEF measurement. Results: A majority of the BC patients had evidence of myocardial injury (hs-cTnI >female ULN=90%) or myocardial dysfunction (NT-proBNP >overall ULN=91%) at any timepoint with fewer patients having abnormal CRP or H-FABP concentrations (H-FABP >ULN=14%; CRP >ULN=45%). Myocardial injury and dysfunction were most evident during the first two cycles of trastuzumab treatment, with myocardial injury also evident during this early timeframe in the female lymphoma patients (3 with hs-cTnI >ULN). In the 12 patients who completed trastuzumab with normal LVEFs (median=60% at 6-months), myocardial injury (hs-cTnI >ULN) and dysfunction (NT-proBNP >ULN) was evident in >50% of patients. Four of the 22 patients did develop cardiotoxicity, but there was no difference in biomarker concentrations between patients with or without cardiotoxicity. Conclusion: The use of the recommended ULN cutoffs identified myocardial injury and dysfunction in a majority of cancer patients in this setting. Biomarker assessments did not relate to cardiac functional imaging studies. Future studies are warranted to assess different cutoffs or biomarker combinations for predicting cardiotoxicity. / Thesis / Master of Science (MSc)

Dilated cardiomyopathy (DCM) or round heart disease is a muscle disease of the heart characterized by left ventricular dilatation and abnormal systolic and diastolic ventricular function. In animals, including turkeys and humans, DCM is a major cause of morbidity and mortality that results in heart failure. In the turkey, DCM can be idiopathic or induced. Since idiopathic or spontaneous DCM occurs in about 2-4 % of normal turkeys, it is of significant concern to the poultry industry. This dissertation was designed to increase our understanding of the pathophysiology of DCM in commercial turkeys. Specific objectives included: evaluating the influence of dietary selenium (Se) and vitamin E on poults fed toxic levels of furazolidone (Fz). Evaluating differences among reciprocal crosses of turkey varieties in susceptibility to a toxic level of Fz that induces DCM were used to assess the role of genetics in DCM. Using glutathione (GSH), glutathione peroxidase (GPx), malondialdehyde (MDA), and plasma uric acid (PUA) as biomarkers, oxidative stress (OS) levels were evaluated. Oxidative stress was also evaluated in poults fed diets containing varying concentration and combinations of vitamin E (0, 50 and 100 IU/kg) and Se (0.0, 0.3 and 0.5 mg/kg). Results from echocardiography measurements at four weeks of age, for poults fed toxic levels of Fz, showed the Narragansett x Bourbon Red reciprocal cross had the lowest internal-diastolic (LVIDd) and systolic dimensions (LVISd), while the Bourbon Red x Narragansett reciprocal cross had the largest LVIDd and LVISd. Left ventricular internal-diastolic and systolic dimension were lower for cross bred than parental poults. In treatment poults, heterosis for ventricular dilation was most significant for Bourbon Red x Narragansett cross. The data suggest that reciprocal crosses respond differently to toxin that induces DCM and genetics may influence a turkey's response to toxic levels of Fz that causes DCM. Results from OS measurements in poults fed normal and those fed normal diets with Fz at two weeks of age, showed no significant differences in MDA and GPx levels. PUA and GSH levels were however significantly increased for poults fed Fz-containing diets. At four weeks of age, no differences were observed for MDA and GPx measurements between poults fed normal and Fz-containing diets. PUA levels increased for poults fed normal diets with Fz, while GSH levels increased only for those fed normal diets. Differences between poults fed normal and Fz-containing diets were significant for GPx measurements. Results of this study showed that, feeding diets with Fz does not increase OS. Measure of the influence of feeding diets supplemented with different concentrations and combinations of Se and vitamin E to poults fed either normal or normal diets with Fz at two and four wks of age, showed higher MDA levels for poults fed Fz-containing diets supplemented with 0.3 mg/kg Se and 100 IU/kg vitamin E. For antioxidant biomarkers, GPx activity were increased for poults fed normal diets with Fz supplemented with 0.5 mg/kg Se and those fed 100 IU/kg vitamin E. Poults fed normal diets supplemented with 100 IU/kg vitamin E had the highest GPx. PUA levels were higher for poults fed normal diets with Fz supplemented with 0.5 mg/kg Se at two wks of age. At four wks of age, PUA concentrations were higher for poults fed Fz-containing diets supplemented with 100 IU/kg vitamin E. Increased PUA were also observed for poults fed diets supplemented with 0.5 mg/kg Se and 50 IU/kg vitamin E and 0.5 mg/kg and 100 IU/kg vitamin E. Poults fed diets supplemented with 50 and 100 IU/kg vitamin E had the highest GSH at two wks of age. Measurements taken at 2 wks of age, for poults fed normal diets supplemented with different concentrations and combinations of Se and vitamin E had increased GSH levels when compared with those fed diets with Fz at four wks of age. In this study, we showed that supplementation of poults fed normal diets with Fz with different concentrations and combinations of Se and vitamin E did not reduce DCM at 2 wks of age. However, at 4 wks of age, though DCM was not decreased by feeding diets supplemented with different concentrations and combinations of Se and vitamin E, reduced oxidant and antioxidant biomarkers were observed. / Ph. D.

The relationship among oxidative stress, mitochondrial DNA integrity, and longevity continues to be without a general consensus. Here, we hypothesize that short- and long-lived birds, including the budgerigar (Melopsittacus undulatus), guineafowl (Numida meleagris), quail (Corturnix japonica), and turkey (Meleagris gallopavo) differ in oxidative stress measured by blood markers and that this difference correlates with mitochondrial genomic integrity both within and among species. In preliminary studies and to establish a reference and standard for the search for single nucleotide polymorphisms (SNPs), we used a combination of experimental and in silico tools for genome analysis to screen selected regions of the chicken (Gallus gallus) mitochondrial genome (mtGenome) for SNPs. A total of 113 SNPs was identified which formed 17 haplotypes. The length of the turkey mtGenome sequence developed was 16,967 bp in length, while that of the budgie was 18,193 bp. Annotation of both sequences revealed a total of 13 genes and 24 RNA (22 tRNA and 2 rRNA). Within the budgie mtGenome sequence, a duplicated control region was observed, and there was an additional nucleotide in the NADH dehydrogenase subunit 3 sequence of both the turkey and budgie. The total number of SNPs within the D-loop and 16S rRNA in each of the four species ranged from zero in the quail to 22 in the budgie. The new mtGenome sequences revealed that the turkey was most closely related to the chicken and quail, and the budgie was closest to kakabo (Strigops habroptilus). Oxidative stress, estimated by biomarkers thiobarbiturate acid reacting substance (TBARS), plasma uric acid (PUA), and glutathione (GSH) and at 10, 30, 55, and 80 wks-of-age within each species, was not consistent. The level of GSH was highest in guineafowl, but lowest in budgie. While PUA, an antioxidant, exhibited a significantly (P<0.05) decrease as birds grew order, TBARS, a lipid peroxidation index, increased with age. In general, oxidant and antioxidant status appeared to vary among species and to be significantly affected by age, unlike mutations in the mtDNA which remained the same in younger and older birds. This primary findings and discoveries of this dissertation research include the large scale SNP discovery in previously described and novel avian mtGenomes including the chicken and turkey, the two main poultry species, and the determination that oxidative stress in birds appears to vary with age but that this does not affect mitochondrial DNA variation. Recent evidence of work in mice appears to support results described in this dissertation that mitochondrial DNA mutations do not increase with age, the central paradigm of the "Free Radical Theory of Aging". The dissertation also described resources and data that will be a foundation for the use of birds, especially the budgie, as a model for testing this theory that remains of interest to both agricultural and biomedical sciences. / Ph. D.

Work-related musculoskeletal disorders (WMSDs) continue to present a substantial personal and economic burden. Biomarkers, in providing objective measures of physiological changes, may offer advantages over current tools for WMSD risk assessment. Existing work has identified biomarkers of cartilage and muscle damage, and demonstrated responsiveness to various forms of physical activity and biomechanical loading. Here, three studies were complete to further assess the occupational relevance/utility of three selected biomarkers: Cartilage Oligomeric Matrix Protein (COMP), Interleukin-6 (IL6), and Creatine Kinase (CK). First, the effects of age, obesity, gender, and diurnal variation was investigated. Significant effects of time, age, and gender were evident, as well as some interactive effects, for COMP and CK, but not IL6. Second, biomarker levels were compared between individuals in occupations having relatively high and low WMSD risk. IL6 levels were greater in the high-risk group, while COMP levels demonstrated an oscillatory pattern, and CK levels did not vary between groups. Third, physical demands were imposed on the lumbar spine during a repetitive flexion/extension task, under conditions with different loading and frequency. IL6 levels varied significantly over time and between added load levels, while CK levels varied over time and was influenced by load and frequency. These studies demonstrate important features of biomarkers; that personal confounding factors need to be considered, that select biomarkers may be sensitive to occupational risk factor exposure, and particularly to task parameters in lifting activities involving the lower back. Further, these studies reveal important information concerning the relevance of the selected biomarkers, favorable time points for biomarker collection, and approximate biomarker levels expected between occupations and exposure to common risk factors. These results support the use of biomarkers in occupational settings for assessing exposure and WMSD risk imposed by common risk factors. Sensitivity to exposure levels is an important precursor to risk prediction, however prospective work is needed to verify predictive validity. / Ph. D.

The discovery of cancer biomarkers is crucial in the clinical setting to facilitate early diagnosis and treatment, thereby increasing survival rates. Proteomic technologies with mass spectrometry detection (MS) have the potential to affect the entire spectrum of cancer research by identifying these biomarkers. Simultaneously, microfabricated devices have evolved into ideal analysis platforms for minute amounts of sample, with promising applications for proteomic investigations and future biomarker screening. This thesis reports on the analysis of the proteomic constituents of the MCF7 breast cancer cell line using a shotgun 2-D strong cationic exchange/reversed phase liquid chromatography electrospray ionization tandem mass spectrometry (SCX/RP-LC-ESI-MS/MS) protocol. A series of optimization strategies were performed to improve the LC-MS experimental set-up, sample preparation, data acquisition and database searching parameters, and to enable the detection and confident identification of a large number of proteins. Over ~4,500 proteins were identified using conventional filtering parameters, and >2000 proteins using a combination of filters and p-value sorting. Of these, ~1,950 proteins had p<0.001 (~90%) and more than half were identified by &#8805; 2 unique peptides. About 220 proteins were functionally involved in cancer related cellular processes, and over 100 proteins were previously described in the literature as potential cancer markers. Biomarkers such as PCNA, cathepsin D, E-cadherin, 14-3-3-sigma, antigen Ki-67, TP53RK, and calreticulin were identified. These data were generated by subjecting to mass spectrometric analysis ~42 µg of protein digest, analyzing 16 SCX peptide fractions, and interpreting ~55,000 MS2 spectra. Total MS time required for analysis was 40 h. Selective SCX fractions were also analyzed by using a microfluidic LC platform. The performance of the microchip LC was comparable to that obtained with bench-top instrumentation when similar experimental conditions were used. The identification of 5 cancer biomarkers was enabled by using the microchip LC platform. Furthermore, this device was also capable to analyze phosphopeptides. / Master of Science