VictorJuiz/thesis huggingface dataset:
High glucose alters mesangial cell protein kinase C activity and isoform cellular content and localization, role of the polyol pathway

High glucose causes diacylglycerol (DAG) accumulation and protein kinase C (PKC) activation in mesangial cells. Our purpose was to determine which of the DAG-sensitive PKC isoforms are affected by high glucose, and whether the polyol pathway plays a role. Primary cultured rat mesangial cells were growth-arrested and cultured in glucose 5.6 mM (NG) or 30 mM glucose (HG) for 48 h, with or without the aldose reductase inhibitor tolrestat or ARI-509. Total PKC activity was measured by an in situ phosphorylation assay. Activation of specific PKC isoforms was inferred by translocation from the cytosol to other cellular compartments, determined by immunoblotting and confocal immunofluorescence microscopy. HG increased total PKC activity; total levels of PKC-$\alpha$, -$\beta\sb2,$ and -$\varepsilon ;$ membrane and particulate PKC-$\alpha ,$ membrane PKC-$\delta$ and PKC-$\varepsilon .$ These HG effects were not due to the increase in osmolality, demonstrated by the L-glucose control. In HG, confocal imaging confirmed an increase in all four PKC isoforms and indicated translocation to the plasma membrane and nucleus of PKC-$\alpha ,$ -$\delta ,$ and -$\varepsilon .$ ARI-509, but not tolrestat, normalized total PKC activity in HG. In HG, both drugs prevented the increase in total PKC-$\varepsilon$ and membrane PKC-$\alpha ,$ -$\delta ,$ and -$\varepsilon .$ In conclusion, we found that HG causes an increase in total PKC activity, accumulation and cellular redistribution of DAG-sensitive PKC isoforms. HG-induced changes in PKC-$\varepsilon$ content and membrane-association of PKC-$\delta ,$ and -$\varepsilon ,$ and possibly PKC-$\alpha ,$ are polyol pathway-dependent.
Characterization of human endothelin converting enzyme (ECE-1) promoter diversity in vasular endothelial cells

Endothelin converting enzyme-1 (ECE-1) catalyzes the conversion of big endothelin-1 to the potent vasoconstrictor endothelin-1 (ET-1) and is a key regulator for the modulated expression of ET-1 in health and disease. To gain further insight into the molecular basis of ET-1 regulation, the structures of ECE-1 mRNA transcripts in vascular endothelial cells were defined. A remarkable degree of mRNA complexity was evident. Five unique ECE-1 mRNA variants which diverged at their 5$\sp\prime$-termini were detected in vascular endothelial cells and designated ECE-1a, -1b, -1c, -1d and -1e. Three of these variants (ECE-1c, -1d, -1e) are novel. This structural mRNA diversity was also observed in various human tissues although expression of certain ECE-1 variants exhibited relative tissue-specificity. To determine the molecular mechanisms underlying this diversity, the structural organization of human ECE-1 5$\sp\prime$-flanking genomic regions was characterized using sequence analysis and restriction mapping of human genomic ECE-1 PAC clones. Five unique examples of exon 1 were evident with distinct 5$\sp\prime$-flanking regions. Each 5$\sp\prime$-flanking region exhibited functional promoter activity in endothelial cells confirming that alternate promoters direct the expression of each ECE-1 variant. The 5$\sp\prime$-flanking region of ECE-1c exhibited robust promoter activity and possessed arrays of potential functionally significant cis-acting DNA elements including Sp1, Krox24/Egr-1, CCAAT-binding, E2A, AP-2 and Ets family member recognition motifs. 5$\sp\prime$-3$\sp\prime$-nested deletion analysis of ECE-1c promoter sequence identified both functionally important positive and negative regulatory domain. Furthermore, an extraordinary degree of allelic diversity was present in the proximal promoter of exon 1c. Taken together, ECE-1c represents a new and major endothelial isoform. Determining the mechanisms by which the ECE-1 isoforms are regulated in endothelial cells may shed light on how gene expression is modulated in this cell type.
Organ injury following ruptured abdominal aortic aneurysm is mediated by oxidants

Mortality following successful RAAA repair remains near 50% and is correlated with the development of progressive organ failure (renal, pulmonary, and hepatic failure). Although the mechanisms responsible for this organ failure are not well characterized, there is growing clinical evidence suggesting that repair of a RAAA induces an inflammatory state which contributes to MOF and death [9]. A rat model of RAAA was employed to examine the role of oxidants in the development of remote organ failure. The synergistic nature of sequential I/R events (HS and aortic occlusion) was confirmed by the development of significant pulmonary dysfunction. Additional experiments examined the ability of a novel anti-oxidant, EUK 134, to reduce organ injury. Administration of EUK 134 following the period of HS resulted in a dramatic reduction in both local and remote organ injury. EUK 134 also markedly reduced tissue PMN leukosequestration. However, despite the significant protection from organ injury afforded by EUK 134, no reduction in F2-isoprostanes was observed. (Abstract shortened by UMI.)
The role of glucoregulation in alcohol intake

The glucostatic theory has been implicated in controlling feeding behavior in experimental animals. Since alcohol is a food substance, alcohol intake may also be regulated by a glucostatic mechanism. Naive Wistar rats drinking alcohol and water under the limited access procedure provide a model of human alcohol consumption used in this thesis to explore the role of glucoregulatory processes in alcohol intake. Peripheral glucose injections and ATP did not reduce alcohol consumption. Although glucose utilization was increased after glucose injections in the chronically food-deprived rats, glucose injections again did not attenuate alcohol intake. Endogenously elevated blood glucose had no effect on alcohol consumption in the streptozotocin-induced diabetes. The glycogenolytic inhibitor, trifluoperazine and the ATP synthesis inhibitor, 2,4-dinitrophenol were found to have no effect on the naltrexone-induced reduction of alcohol intake. Although an inverse relationship was found between the blood glucose and alcohol intake using two $\alpha\sb2$-adrenoceptor antagonists, the results from idazoxan were not robust. Taken together, these findings suggest that glucoregulatory processes do not play a role in the control of alcohol intake.
A study of premorbid diet and prostate cancer survival

207 population-based cases of prostate cancer from Toronto and 201 cases of prostate cancer from Vancouver answered diet histories at diagnosis between 1989 and 1992 and were passively followed for survival from prostate cancer. After adjustment for energy, stage, grade, and other factors, significantly lower risks of dying from prostate cancer for cases in the highest compared with the lowest tertiles of monounsaturated fat intakes were observed in each city and in the combined city analyses (results for the latter: Cox hazard ratio = 0.26; p value for trend = 0.01). A significant, inverse relation between energy intake and survival from prostate cancer corresponding to the highest tertile was observed in Toronto (adjusted hazard ratio = 0.09; p value for trend = 0.005) but not in Vancouver (adjusted hazard ratio = 2.64; p value for trend = 0.1). Given the low response rate of the Toronto cases, the observed energy association in Toronto was potentially attributable to non-respondent bias.
Development of radioligands for imaging phosphodiesterase-4 in the human brain using positron emission tomography

Phosphodiesterase-4 (PDE4) is one of the main enzymes responsible for metabolizing cyclic 3',5'-adenosine monophosphate (cAMP) following stimulation of at least ß-adrenergic, A2-adenosine, and H2-histamine receptors in the brain. PDE4 expression is regulated in concert with cAMP-mediated signaling in the short-term via phosphorylation (within 15 min) and in the long term ' via de novo' protein synthesis (within hours to days). Disturbances in cAMP-mediated signaling may occur in depression, and the activation of components in this pathway, including PDE4, is a potential mechanism of action of antidepressants. We developed a radioligand with the future aim of imaging PDE4 in the brain of living depressed patients, using positron emission tomography (PET). The selective PDE4 inhibitor 'R'-rolipram was successfully labeled with carbon-11 and displayed the best 'in vivo' pharmacological profile in rats as compared to the racemic form or to another PDE4 inhibitor, [11C]Ro 20-1724. 'R'-[11C]Rolipram showed higher brain uptake in PDE4-rich areas (e.g., frontal cortex) over the brain stem (poor in PDE4), and selectivity for PDE4 over PDE1, another abundant PDE in the brain. 'R'-[11C]Rolipram yielded a favorable metabolism profile, with no radioactive metabolites crossing the blood-brain barrier, and was considered safe for injection in humans. Acute and chronic challenges with drugs expected to increase PDE4 regulation in neurotransmitter systems linked to PDE4, including the noradrenaline reuptake inhibitor desipramine (DMI) and the serotonin reuptake inhibitor fluoxetine, augmented 'R'-[11C]Rolipram binding in rat brain. DMI and fluoxetine increased 'R'-[11C]rolipram ' specific binding' by 10-41% across brain regions. 'In vitro' validation with 'R'/'S'-[ 3H]rolipram supported these findings, since acute and chronic DMI, and acute fluoxetine, significantly increased the Bmax in rat frontal cortex by 27-54%. In contrast, activation of dopamine-D1 receptors (likely linked to PDE1) by SKF 81297 had no significant effect on ' R'-[11C]rolipram brain retention, showing that the radioligand discriminates among different systems in detecting the regulation of PDE4. 'R'-[11C]Rolipram is unlike [ 18F]fluorodeoxyglucose or [15O]water, which monitor variations in neuronal activity regardless of the systems involved. PET imaging with 'R'-[11C]rolipram in normal human volunteers showed a high signal in gray matter areas of the brain. These studies demonstrated that 'R'-[11C]rolipram has potential for imaging PDE4 in the living human brain using PET.
Monte Carlo inference for belief networks using coupling from the past

A common method of inference for belief networks is Gibbs sampling, in which a Markov chain to the desired distribution is simulated. In practice, however, the distribution obtained with Gibbs sampling differs from the desired distribution by an unknown error, since the simulation time is finite. Coupling from the past selects states from exactly the desired distribution by starting chains in every state at a time far enough back in the past that they reach the same state at time 't' = 0. To track every chain is an intractable procedure for large state spaces. The method proposed in this thesis uses a summary chain to approximate the set of chains. Transitions of the summary chain are efficient for noisy-or belief networks, provided that sibling variables of the network are not directly connected, but often require more simulation time steps than would be needed if chains were tracked exactly. Testing shows that the method is a potential alternative to ordinary Gibbs sampling, especially for networks that have poor Gibbs sampling convergence, and when the user has a low error tolerance.
Aging and Shiftwork Tolerance

This field research examined the effects of age on the ability to tolerate shiftwork and evaluated the effect of coping with shiftwork on age-related differences. The former was studied by examining the age-related differences in sleep, circadian, social factors and health. The latter was examined (a) by comparing these age-related differences among shift- and dayworkers and (b) by studying sleep and circadian changes among shiftworkers as a function of the length of previous experience of shiftwork. The sensitivity of older shiftworkers to sleep loss was examined by determining whether with increasing age less sleep is needed or the ability to obtain the needed sleep declines. Older workers' susceptibility to the circadian disruptions of shiftwork was also investigated by examining the age-related differences in the phase and amplitude of the circadian rhythms. Subjective sleep need did not decline with age among shift- or dayworkers although shiftworkers needed more sleep. The predicted sleep needed for best performance increased with age. This increase was larger in shiftworkers than in dayworkers. Older participants were less able to obtain the sleep they needed subjectively, or which was associated with best performance. This ability, and the quality of sleep, was inferior among shiftworkers than dayworkers, particularly on workdays and at older age levels. With increasing age, the circadian phase advanced and the sleeping habits became more rigid, but such impact of age did not differ between shift and non-shiftworkers. An age-related decline was also observed in the amplitude, which was greater among shiftworkers than dayworkers, particularly in old age. However, this decline was associated with poor sleep and health and thus might not be purely age-related. Although health generally deteriorated with age, shiftworkers, had more health problems than dayworkers, particularly at older age levels and on workdays. Longer experience with shiftwork was found to be associated with deterioration in sleep, circadian and health variables, particularly at older age levels. The results of this study suggest that shiftwork becomes less tolerable beyond the age of 40. Age and length of shiftwork experience seem to interactively affect older shiftworkers ability to cope with shiftwork. A descriptive model is proposed for further research on this interaction.
Over-expression of the serine elastase inhibitor elafin in vein grafts, insight into the mechanism of neointimal formation and a potential therapeutic strategy against atherosclerotic degeneration

In previous studies, we used the selective serine elastase inhibitor elafin to attenuate experimental transplant coronary arteriopathy, thereby establishing an association between leukocyte infiltration, elastase activity, and neointimal formation. We now investigate whether vein grafts are also associated with leukocyte infiltration and elevated serine elastase activity and determine if this contributes to neointimal formation by using a gene transfer approach to anti-elastase therapy. Our results suggest that a gene transfer approach to serine elastase inhibition modifies the early phase of vein graft remodeling associated with inflammation and this appears not only to delay neointimal formation but to protect against late atherosclerotic degeneration.
Are you better? Describing and explaining changes in health status in persons with upper-extremity musculoskeletal disorders

"Are you better?" is a fundamental question for both clinical practice and clinical research. Measuring changes in health status questionnaire scores is one way we attempt to answer the question in a standardized way, but how do we know if they do it well? The ability of a questionnaire to accurately detect change when it has occurred is called responsiveness. This is tested by examining change score in patients deemed to be improved by some reasonable indicator of true change. This thesis shows that the description of an instruments responsiveness is dependent on the indicator used. Measures are not "responsive" but are "responsive to ... ". A taxonomy is developed describing different types of change (i.e., important change) and different perspectives that can be taken (patient, clinician). Each category is a different kind of responsiveness. One perspective, the patient's, is examined in detail in a qualitative study. The results show that being "better" is highly individualized, and may have little to do with a change in health state. This perspective is operationalized in a cohort study evaluating if different categories of change (cells in the taxonomy) result in different descriptions of an instruments responsiveness. The results show a high degree of variability. "Are you better?" is challenging to measure, but it is usually the question we are trying to answer when health status questionnaires are used in evaluative manners. Responsiveness studies need to be designed with attention to the indicator being used for change, which should reflect the target application.
The use of hair analysis to qualitatively and quantitatively assess cocaine use in adult users and neonates exposed in utero

Accurate and objective drug use assessment is needed to ensure appropriate and adequate treatment. However, it is limited by COC's illicit nature. The objectives were to: (a) corroborate use status by urinalysis and hair analysis of proximal and distal ends, (b) correlate avg [COC] & [BZ] in 1.5cm. sections to the corresponding self-reported COC use and, (c) evaluate the clinical utility of the hair test in neonates. ' Admitted Adult Users'. Hair analysis confirmed historical COC use and characterized historical use patterns, where urinalysis was ineffective. Analysis of hair clippings at each end confirmed use in 95% of the participants. Qualitatively, sectional analysis (1.5cm sections) corroborated reported use patterns in 53% of participants. Quantitatively, the relationship between average [COC] & [BZ], and the average reported use over the full length of the hair shaft was weak but significant (COC Rho = 0.34; BZ Rho = 0.42). Confounders including ethnicity, natural hair colour, cosmetic hair treatment, and external contamination weakened the correlation. Darker coloured hair, particularly black hair, incorporated more COC & BZ, despite reporting the use of substantially less COC. Whereas, blonde hair incorporated the least COC, supporting a significant role for melanin in COC incorporation. Also, higher [COC] & [BZ] were observed in women, in those who did not treat their hair, and in those who were Black. Although external contamination can be significant, coanalysis of COC & BZ provided an indication of systemic COC burden. 'Neonates'. 192 samples were referred to HSC. 55 (30%) were positive, 5-fold higher than the rate in a Toronto population study (p < 0.001) and [BZ] was 2-fold higher (p = 0.0001). Hair analysis confirmed clinical suspicions of fetal exposure to COC in s subgroup of heavy COC users, who are probably at higher perinatal risks.
Anchoring of maternal RNAs in the oocyte of the clawed frog, Xenopus laevis

The body plan of the embryo is established by a polarized source of developmental information in the oocyte. The 'X. laevis' oocyte creates polarity by anchoring mRNAs in the vegetal cortex, including ' Vg1', which may function in body plan specification, and ' Xwnt-11' and 'Xcat-2', which may function in germ cell development. To identify components of the RNA anchoring mechanism, I used manually isolated vegetal cortices (IVC) to assay loss or change in spatial arrangement of RNAs caused by disruption of cortical elements. The role of cytoskeleton in RNA anchoring was tested by treating oocytes with inhibitors that selectively disrupted actin filaments and cytokeratin filaments, and by using the IVC to assay for RNAs. Treatment of oocytes with cytochalasin B caused clumping of 'Vg1' and 'Xwnt-11' as revealed by 'in situ' hybridization of IVCs, but did not cause their release as confirmed by RT-PCR analysis. These RNA clumps did not match the distribution of actin filament clumps, but they appeared to be similarly distributed as the remnant cytokeratin filaments. Treatment of oocytes with anti-cytokeratin antibody C11 released these RNAs from the cortex. C11 altered the texture of the cytokeratin network, but did not affect the actin meshwork. From these results, I concluded that 'Vg1' and 'Xwnt-11 ' are retained by a cytokeratin filament-dependent mechanism, and that organization of the cytokeratin network depended on an intact actin meshwork. Colcemid did not disrupt 'Vg1' and 'Xwnt-11' retention by the IVC, so anchoring of these RNAs are independent of microtubules. Membrane disruption in the IVC by Triton X-100 decreased 'Vg1 ' and 'Xwnt-11'. The disappearance of these RNAs was mainly due to degradation by ribonuclease activity released from membrane components. However, more 'Vg1' and 'Xwnt-11' were recovered in the supernatant upon treatment of IVCs on ice, which diminished ribonuclease activity. This suggested that a fraction of these RNAs required membranes to be retained in the cortex. Cytochalasin B, C11, colcemid, and Triton X-100 on ice neither released nor degraded 'Xcat-2' mRNA, so no cortical element could be implicated in its anchoring. 'Xcat-2' was also more resistant to endogenous ribonuclease activity compared to 'Vg1 ' and ' Xwnt-11'.
A few laced genes, sociology, the women's movement and the work of Dorothy E. Smith

This dissertation examines the productive forces which gave rise to a sociological method called the Social Organization of Knowledge (SOK), formulated by the Canadian sociologist Dorothy E. Smith. The method is used to study the organizing power of objectified knowledge found in textually-mediated forms of discourse. It was created as a subversive response to the traditional canon of the sociology of knowledge. Smith has a feminist ancestry, in that her direct foremother is Margaret Fell. The thesis begins with Fell's life from her conversion to Quakerism in 1652, and continues with the militant Suffragette experience of Lucy Ellison Abraham and Dorothy Foster Abraham, Smith's mother and grandmother. It then proceeds with Smith's early life in England and the development of the SOK is traced through her doctoral studies at the University of California at Berkeley, the Vancouver Women's Movement, 1968-1977, and the Toronto Women's Movement from 1977 to the present. A central argument in this dissertation is that the women's movement, in its ongoing historical manifestations acts as a productive force for change. Women's movements are represented in a way as to reflect the empirical reality of Smith's feminist lineage, lived life, and her lifework. Historical materialism is used to reproduce women's lives, employing the term, appropriated from Marx's 'The German Ideology', of 'productive forces', defined as the innovative ways which women, over time, have used household labour to advance their work for women's equality. I argue that through the qualities that were offered to Smith in an intergenerational experience of feminism, and the imaginative use of the historical moment in the Vancouver Women's Movement, she created an identity for herself as a feminist sociologist, shaping, over her sociological career, a new contribution to the sociology of knowledge, the SOK method. The dissertation is categorized as interpretive historical sociology. Data were collected by: (1) indepth interviews; (2) participant observation; and (3) library, archival, and database research.