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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Kvinnors upplevelse av att hantera egenvården vid typ 2 diabetes : En systematisk litteraturstudie

Liljeqvist Åström , Åsa, Lundström, Anna January 2009 (has links)
<p>Både nationellt och internationellt ses en stark ökning av typ 2 diabetes vilket har bidragit till att sjukdomen blivit en av de huvudsakliga orsakerna till för tidig sjukdom och död i de flesta länder. Sjukdomsdebuten kryper allt lägre ned i åldrarna och kräver att individen utför en adekvat egenvård för att undvika att drabbas av komplikationer. Syftet med denna systematiska litteraturstudie var att beskriva kvinnors upplevelse av att hantera egenvården vid typ 2 diabetes. Studien baseras på tio vetenskapliga artiklar som analyserats med kvalitativ induktiv analysmetod. Analysen resulterade i fem kategorier som visade sig påverka kvinnors upplevelse av att hantera sin egenvård: Upplevelsen av att tvingas anpassa sig, Upplevelsen av motivation, Upplevelsen av vårdgivares stöd, Upplevelsen av omgivningens förståelse och Upplevelsen av att hantera sina känslor. Kvinnor påverkas i stor utsträckning av den information och det bemötande de får av vårdgivare både efter att ha fått diagnosen och vidare. För att kvinnor ska stärkas i sin egenvårdskapacitet bör stöd och information anpassas till kvinnans aktuella livssituation. Familjen har stor betydelse för kvinnors upplevelse av att hantera egenvården vilket kräver att omvårdnaden även bör innefatta familjen. Vidare forskning bör fokusera på familjens upplevelse när någon i familjen drabbas av typ 2 diabetes.</p><p> </p>
372

Protein Profiling and Type 2 Diabetes

Sundsten, Tea January 2008 (has links)
<p>Type 2 diabetes mellitus (T2DM) is a heterogeneous disease affecting millions of people worldwide. Both genetic and environmental factors contribute to the pathogenesis. The disease is characterized by alterations in many genes and their products. Historically, genomic alterations have mainly been studied at the transcriptional level in diabetes research. However, transcriptional changes do not always lead to altered translation, which makes it important to measure changes at the protein level. Proteomic techniques offer the possibility of measuring multiple protein alterations simultaneously.</p><p>In this thesis, the proteomic technique surface enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF MS) has been applied and evaluated in the context of T2DM research. Protocols for pancreatic islet and serum/plasma protein profiling and identification have been developed. In addition, the technique was used to analyze the influence of genetic background versus diabetic environment by determining serum protein profiles of individuals with normal glucose tolerance (NGT) and T2DM with or without family history of diabetes. In total thirteen serum proteins displayed different levels in serum from persons with NGT versus patients with T2DM. Among these proteins, apolipoprotein CIII, albumin and one yet unidentified protein could be classified as being changed because of different genetic backgrounds. On the other hand, ten proteins for instance transthyretin, differed as a result of the diabetic environment.</p><p>When plasma protein patterns of NGT and T2DM individuals characterized by differences in early insulin responses (EIR) were compared, nine proteins were found to be varying between the two groups. Of these proteins five were identified, namely two forms of transthyretin, hemoglobin α-chain, hemoglobin β-chain and apolipoprotein H. However no individual protein alone could explain the differences in EIR. In conclusion, SELDI-TOF MS has been successfully used in the context of T2DM research to identify proteins associated with family history of diabetes and β-bell function. </p>
373

Mental health and chronic medical conditions: schizophrenia, its treatment, risk of metabolic complications, and health care utilization

Bresee, Lauren 11 1900 (has links)
Objective - To assess the relationship between schizophrenia and cardiovascular disease by evaluating metabolic risk associated with treatment for schizophrenia, prevalence of cardiovascular risk factors (CV-RF) and disease (CV-D), and health care utilization in people with schizophrenia compared to the non-schizophrenic population. Methods Four studies were completed to evaluate the dissertation objectives. A systematic review was completed to quantify the change in metabolic parameters associated with use of atypical antipsychotic agents. The second study utilized a period prevalence design to compare prevalence of CV-RF (diabetes, hypertension, dyslipidemia) and CV-D in people with and without schizophrenia using the administrative databases of Alberta Health and Wellness. General and cardiac specialist health care utilization was evaluated in people with schizophrenia using data from Alberta Health and Wellness. Lastly, results from the Canadian Community Health Survey were used to evaluate prevalence of CV-RF and CV-D while controlling for important lifestyle and demographic variables unavailable in the databases of Alberta Health and Wellness. Results Use of atypical agents, particularly clozapine, resulted in statistically significant weight gain and increases in total cholesterol and blood glucose compared to typical agents. Having schizophrenia was associated with a significantly higher prevalence of diabetes, obesity, smoking, and CV-D compared to people without schizophrenia. Individuals with schizophrenia visited a general practitioner and the emergency department more often, and were more likely to be hospitalized than those without schizophrenia. Despite having a higher prevalence of coronary artery disease, individuals with schizophrenia were significantly less likely to visit a cardiologist or undergo revascularization compared to people with coronary artery disease who did not have schizophrenia. Conclusion Individuals with schizophrenia have a considerable burden of cardiovascular disease compared to people without schizophrenia. This is likely a result of a number of factors, including medications used to treat schizophrenia, the increased prevalence of smoking and other unhealthy lifestyle factors, and the increased prevalence of cardiovascular risk factors in people with schizophrenia. Individuals with schizophrenia utilize the general health care system more frequently than their non-schizophrenic counterparts, therefore the opportunity exists for monitoring for and management of modifiable cardiovascular risk factors in this vulnerable population.
374

Protein Profiling and Type 2 Diabetes

Sundsten, Tea January 2008 (has links)
Type 2 diabetes mellitus (T2DM) is a heterogeneous disease affecting millions of people worldwide. Both genetic and environmental factors contribute to the pathogenesis. The disease is characterized by alterations in many genes and their products. Historically, genomic alterations have mainly been studied at the transcriptional level in diabetes research. However, transcriptional changes do not always lead to altered translation, which makes it important to measure changes at the protein level. Proteomic techniques offer the possibility of measuring multiple protein alterations simultaneously. In this thesis, the proteomic technique surface enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF MS) has been applied and evaluated in the context of T2DM research. Protocols for pancreatic islet and serum/plasma protein profiling and identification have been developed. In addition, the technique was used to analyze the influence of genetic background versus diabetic environment by determining serum protein profiles of individuals with normal glucose tolerance (NGT) and T2DM with or without family history of diabetes. In total thirteen serum proteins displayed different levels in serum from persons with NGT versus patients with T2DM. Among these proteins, apolipoprotein CIII, albumin and one yet unidentified protein could be classified as being changed because of different genetic backgrounds. On the other hand, ten proteins for instance transthyretin, differed as a result of the diabetic environment. When plasma protein patterns of NGT and T2DM individuals characterized by differences in early insulin responses (EIR) were compared, nine proteins were found to be varying between the two groups. Of these proteins five were identified, namely two forms of transthyretin, hemoglobin α-chain, hemoglobin β-chain and apolipoprotein H. However no individual protein alone could explain the differences in EIR. In conclusion, SELDI-TOF MS has been successfully used in the context of T2DM research to identify proteins associated with family history of diabetes and β-bell function.
375

Sagittal abdominal diameter is a more independent measure compared with waist circumference to predict arterial stiffness in subjects with type 2 diabetes - a prospective observational cohort study

Dahlén, Elsa, Bjarnegård, Niclas, Länne, Toste, Nyström, Fredrik H., Östgren, Carl Johan January 2013 (has links)
Background Anthropometric measurements are useful in clinical practice since they are non-invasive and cheap. Previous studies suggest that sagittal abdominal diameter (SAD) may be a better measure of visceral fat depots. The aim of this study was to prospectively explore and compare how laboratory and anthropometric risk markers predicted subclinical organ damage in 255 patients, with type 2 diabetes, after four years. Methods Baseline investigations were performed in 2006 and were repeated at follow-up in 2010. Carotid intima-media thickness (IMT) was evaluated by ultrasonography and aortic pulse wave velocity (PWV) was measured with applanation tonometry over the carotid and femoral arteries at baseline and at follow-up in a cohort of subjects with type 2 diabetes aged 55–65 years old. Results There were significant correlations between apolipoprotein B (apoB) (r = 0.144, p = 0.03), C - reactive protein (CRP) (r = 0.172, p = 0.009) at baseline and IMT measured at follow-up. After adjustment for sex, age, treatment with statins and Hba1c, the associations remained statistically significant. HbA1c, total cholesterol or LDL-cholesterol did not correlate to IMT at follow-up. Baseline body mass index (BMI) (r = 0.130, p = 0.049), waist circumference (WC) (r = 0.147, p = 0.027) and sagittal Abdominal Diameter (SAD) (r = 0.184, p = 0.007) correlated to PWV at follow-up. Challenged with sex, SBP and HbA1c, the association between SAD, not WC nor BMI, and PWV remained statistically significant (p = 0.036). In a stepwise linear regression, entering both SAD and WC, the association between SAD and PWV was stronger than the association between WC and PWV. Conclusions We conclude that apoB and CRP, but not LDL-cholesterol predicted subclinical atherosclerosis. Furthermore, SAD was more independent in predicting arterial stiffness over time, compared with WC, in middle-aged men and women with type 2 diabetes. / <p>Funding Agencies|Medical Research Council of Southeast Sweden||Center for Medical Image Science and Visualization (CMIV)||Linkoping University||Futurum||King Gustaf V and Queen Victoria Freemason Foundation||GE Healthcare||Swedish Heart-Lung Foundation||Swedish Research Council Grant|12661|</p>
376

Mechanisms of Fatty Acid Induced Decrease in β-cell Function

Oprescu, Andrei Ioan 25 September 2009 (has links)
An important mechanism involved in the pathogenesis of type 2 diabetes is elevation of plasma free fatty acids which induce insulin resistance and may impair both β-cell function and mass (β-cell lipotoxicity). The objective of my thesis was to investigate the role of oxidative stress in β-cell lipotoxicity, using in vivo, ex vivo, and in vitro models. I used in vivo models of 48h i.v. oleate or olive oil infusion in Wistar rats followed by hyperglycemic clamps, or islet secretion studies ex vivo, and in vitro models of 48h exposure to oleate in isolated islets. My first study showed that 48h oleate infusion decreased the insulin response to a hyperglycemic clamp, an effect prevented by coinfusion of the antioxidants N-acetylcysteine and taurine. Similar to the findings in vivo, 48h infusion of oleate decreased glucose stimulated insulin secretion (GSIS) ex vivo, and induced oxidative stress in isolated islets, effects prevented by coinfusion of the antioxidants N-acetylcysteine, taurine, or tempol. Islets exposed to oleate or palmitate showed a decreased insulin response to high glucose and increased levels of oxidative stress, effects prevented by taurine. Therefore, my data are the first demonstration that oxidative stress plays a role in the decrease in β-cell secretory function induced by prolonged exposure to FFA, in vitro and in vivo. My second study addressed downstream effects of oxidative stress involving inflammation. A 48h infusion of oleate or olive oil decreased β-cell function during a hyperglycemic clamp, an effect prevented by coinfusion of the IKKβ inhibitor salicylate. GSIS in isolated islets was impaired by olive oil or oleate and restored by salicylate. These results suggest a potential role for both oxidative stress and inflammation in lipid-induced β-cell dysfunction. My third study addressed downstream effects of oxidative stress involving β-cell insulin signalling. A 48h infusion of oleate or olive oil decreased β-cell function during a hyperglycemic clamp, an effect prevented by coinfusion of the tyrosine phosphatase inhibitor bisperoxovanadate. GSIS in isolated islets was impaired by olive oil or oleate and restored by bisperoxovanadate, suggesting a role of FFA in decreasing β-cell function by induction of β-cell insulin resistance.
377

Mechanisms of High Glucose-induced Decrease in β-cell Function

Tang, Christine 23 February 2011 (has links)
Chronic hyperglycemia, a hallmark of type 2 diabetes, can decrease β-cell function and mass (β-cell glucotoxicity); however, the mechanisms are incompletely understood. The objective was to examine the mechanisms of β-cell glucotoxicity using in vivo and ex vivo models. The hypothesis is that oxidative stress plays a causal role in high glucose-induced β-cell dysfunction in vivo via pathways that involve endoplasmic reticulum (ER) stress and JNK. The model of β-cell glucotoxicity was achieved by prolonged i.v. glucose infusion (to achieve hyperglycemia). In Study 1, 48h glucose infusion increased total and mitochondrial superoxide levels in islets, and impaired β-cell function in vivo and ex vivo. Co-infusion of the superoxide dismutase mimetic Tempol decreased total and mitochondrial superoxide, and prevented high glucose-induced β-cell dysfunction in vivo and ex vivo. These results suggest that increased superoxide generation plays a role in β-cell glucotoxicity. In Study 2, 48h glucose infusion increased activation of the unfolded protein response (XBP-1 mRNA splicing and phospho-eIF2α levels). This was partially prevented by Tempol. Co-infusion of the chemical chaperone 4-phenylbutyrate with glucose decreased spliced XBP-1 levels, and prevented high glucose-induced β-cell dysfunction in vivo and ex vivo. Co-infusion of 4-phenylbutyrate also decreased total and mitochondrial superoxide induced by high glucose. These results suggest that 1) ER stress plays a causal role in high glucose-induced β-cell dysfunction, and 2) there is a link between oxidative stress and ER stress in high glucose-induced β-cell dysfunction in vivo. In Study 3, JNK inhibition using the inhibitor SP600125 in rats or JNK-1 null mice prevented high glucose-induced β-cell dysfunction ex vivo and in vivo. SP600125 prevented high-glucose-induced β-cell dysfunction without decreasing total and mitochondrial superoxide levels. Both Tempol and 4-phenylbutyrate prevented JNK activation induced by high glucose. These results suggest a role of JNK activation in high glucose-induced β-cell dysfunction downstream of increased superoxide generation and ER stress in vivo. Together, the results suggest that 1) oxidative stress, ER stress and JNK activation are causally involved in β-cell glucotoxicity, and 2) High glucose-induced oxidative stress and ER stress are linked, and both impair β-cell dysfunction via JNK activation in vivo.
378

The Role of PTEN in Pancreatic Beta Cells and Insulin Promoter-expressing Neurons in Modulating Glucose Metabolism and Energy Homeostasis

Wang, Linyuan 06 December 2012 (has links)
PI3K signaling in pancreatic β cells has been shown to be important in modulating β cell mass and function under basal condition. Evidence suggests that a specific group of insulin promoter-expressing neurons also modulates glucose metabolism and energy homeostasis through their PI3K signaling. Thus we hypothesize that PI3K activation via PTEN deletion under the control of rat insulin promoter (RIP) in pancreatic β cells and RIP-expressing neurons will protect against hyperglycemia and diabetes in experimentally induced mouse models of type 2 diabetes. In Chapter IV, we showed that RIP-mediated PTEN deletion in pancreatic β cells led to PI3K activation and subsequent increased β cell mass and function, thus protected the mice from high fat diet (HFD)-induced diabetes. Furthermore in the absence of global leptin signaling, β cell-specific PTEN deletion maintained β cell function in the setting of severe insulin resistance, therefore prevented diabetes development. Interestingly, RIP-mediated PTEN deletion also resulted in increased peripheral insulin sensitivity due to PI3K activation in central nervous system. In Chapter V, we showed this increased insulin sensitivity was maintained after HFD feeding, which also contributed to the protection against diabetes. These mice also showed increased visceral adipogenesis and subcutaneous adiposity on HFD, which were dramatically attenuated in the absence of leptin signaling, indicated the essential role of peripheral leptin action in mediating the insulin sensitive phenotype from neuronal RIP PTEN deletion. Finally, we demonstrated that the insulin sensitizing phenotype in these mice was not mediated through ventromedial hypothalamic nuclei (VMH), such that VMH-specific PTEN deletion did not alter energy homeostasis or glucose metabolism. Together, the data from this thesis points to an inhibitory role of PTEN in both central nervous system and pancreatic β cells in glycemic control. Therefore, PTEN may represent a potential target for diabetes prevention and treatment.
379

Examination of Expression and Function of TCF Genes in the Pancreatic Islets

Columbus, Joshua 17 December 2010 (has links)
Specific SNPs in intronic regions of the human TCF7L2 gene are associated with an elevated risk of T2D development and progression. Several investigations have suggested a role of TCF7L2 in pancreatic β-cells. Whether this transcription factor is indeed expressed in the pancreatic islets of rodent species, however, has been a controversial issue. Here, we found that TCF7L2 mRNA level was significantly lower in the pancreas compared to the gut or Ins-1 cell line. In addition, TCF7L2 mRNA abundance in the pancreas was decreased by insulin. Finally, both TCF7 and TCF7L1 but not LEF-1 could be detected in the mouse pancreas. mRNA abundance for these two transcription factors was also decreased by insulin, and the level of TCF7, TCF7L1, and TCF7L2 mRNAs could be down-regulated by HFD. We speculate that reduced expression of these TCF genes during hyperinsulinemia may alter the Wnt signalling pathway and therefore impair the function of β-cells.
380

Examining the Role of Herp in the ER Stress Response of Pancreatic Beta Cells

Siva, Madura 11 January 2011 (has links)
The unfolded protein response, which is activated during ER stress, counteracts stress conditions by increasing folding capacity and by increasing the degradation of misfolded ER proteins by the ER-Associated Degradation (ERAD) system. Studies using an engineered insulinoma cell line with inducible expression of the Akita folding-deficient insulin have shown a large induction of Herp, a protein that has been implicated in the ERAD pathway. We hypothesized that Herp is an essential protein that regulates the degradation of misfolded insulin during the ER stress response. Indeed, we found that the degradation of mutant insulin is Herp-dependent and that maintaining Herp expression is vital for maintaining cell survival. We have also observed that the expression of Herp mRNA and protein is induced in various cell culture and animal models of diabetes. These results suggest that Herp is an important ER stress response protein that is induced under diabetic conditions in pancreatic β-cells.

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