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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.
211

Effet protecteur des HDL en phase aiguë d’AVC ischémique en condition d’hyperglycémie / Protective effect of HDL during acute stroke under hyperglycemic condition

Couret, David 03 December 2018 (has links)
Les accidents vasculaires cérébraux (AVC) ischémiques sont un problème majeur de santé publique. Les thérapies actuellement disponibles se fondent sur une approche vasculaire de la prise en charge. L’arrivée de la thrombectomie mécanique comme traitement de routine de l’AVC, expose le patient à des lésions de reperfusion comme les transformations hémorragiques (TH). L’hyperglycémie aiguë, augmente ce risque. Nous avons mis au point un modèle préclinique pertinent et reproductible chez la souris permettant d’étudier les mécanismes de ces TH. Les lipoprotéines de haute densité (HDL) sont des complexes moléculaires ayant des propriétés protectrices. Nous avons démontré que lors de la phase aiguë de l’AVC, ces HDL subissaient des modifications structurelles et devenaient dysfonctionnelles. Un des mécanismes de cette altération est représenté par l’oxydation des protéines de surface notamment l’apoA-1 par la myéloperoxydase (MPO) libérée par les neutrophiles recrutés dans la zone ischémiée. Le dosage du taux plasmatique de MPO en phase aiguë d’AVC pourrait permettre de mieux caractériser ce mécanisme. L’injection de HDL a déjà prouvé son efficacité dans la diminution de la taille des infarctus cérébraux ainsi que dans la survenue des complications hémorragiques sur des modèles murin d’ischémie cérébrale. L’hypothèse d’un défaut d’efficacité des HDL dans cette condition pathologique particulière nous conduit à envisager une amélioration de leurs fonctions grâce à leur propriété de vecteur de molécules protectrices. Ces HDL seraient alors utilisées comme transporteur de molécules augmentant leur potentiel neuro- et endothélio-protecteur dans le traitement de l’AVC ischémique. / Ischemic stroke is a major public health problem. Currently, available therapies are based on a vascular approach. The advent of mechanical thrombectomy as a routine treatment for stroke exposes the patient to reperfusion injury such as hemorrhagic transformation (HT). Acute hyperglycemia increases this risk. We have developed a relevant and reproducible preclinical model in mice to study the mechanisms of these HT. High density lipoproteins (HDL) are molecular complexes with protective properties. We demonstrated that during the acute phase of stroke, these HDLs become dysfunctional. One of the mechanisms of this alteration is represented by the oxidation of surface proteins including apoA-1 by myeloperoxidase (MPO) released by neutrophils recruited into the ischemic zone. The MPO plasmatic level determination in the acute phase of stroke could be relevant. The injection of HDL has already proved effective in reducing the size of infarct and in the occurrence of HT in murine models of stroke. The hypothesis of a lack of efficiency of HDL in this particular pathological condition leads us to consider an improvement of their functions thanks to their vector property of protective molecules. These HDLs would then be used as a transporter of molecules increasing their neuro- and endothelio-protective potential in the treatment of ischemic stroke.
212

Leptina e ghrelina na fase aguda e de recuperação da cetoacidose diabética em crianças e adolescentes / Leptin and ghrelin during acute and recovery phases of diabetic ketoacidosis in children and adolescents

Roberta Diaz Savoldelli 26 September 2016 (has links)
INTRODUÇÃO: a ação dos hormônios contrarreguladores da insulina na cetoacidose diabética tem sido estudada desde a década 1970-80, e é sabido que seus níveis elevados, aumentando a resistência à insulina, têm papel importante na gênese da CAD. Leptina e ghrelina foram mais recentemente associadas à homeostase da glicose, no entanto, seu papel na CAD ainda é controverso. Os objetivos deste estudo foram: avaliar as alterações nas concentrações séricas de leptina e ghrelina presentes ao diagnóstico da CAD durante os primeiros três dias de seu tratamento e após a estabilização completa do quadro, as correlações com a insulina e outros contrarreguladores, comparando com indivíduos saudáveis. MÉTODOS: foram analisados 25 episódios de cetoacidose diabética em 22 pacientes admitidos no setor de emergência pediátrica de um hospital terciário em São Paulo, Brasil, entre março de 2010 e julho de 2013. Os episódios de cetoacidose foram manejados com reposição endovenosa de fluidos e eletrólitos e análogos de ação ultrarrápida de insulina subcutânea intermitente. Amostras para glicose, insulina, leptina, ghrelina, GH, cortisol e catecolaminas foram obtidas no momento da admissão (T0), durante o tratamento da cetoacidose (após 2, 4, 6, 12, 24 e 72 horas) e em um momento estável após a alta (TE). Os dados foram analisados utilizando-se os testes ANOVA ou Kruskal-Wallis para a comparação de variáveis contínuas durante o tratamento, Teste t de Student ou Mann Whitney para a comparação entre pacientes e grupo controle, e testes de Pearson ou Spearman para correlação entre as variáveis; p < 0.05 foi considerado significativo. RESULTADOS: observamos três fases distintas (a): o diagnóstico de CAD (T0) em que prevalecem hiperglicemia, insulinopenia e elevação de hormônios contrarreguladores; nesse momento, as concentrações de leptina foram menores que no grupo controle, provavelmente relacionadas à insuficiência de energia, estado hipercatabólico e elevação dos hormônios contrarreguladores; as concentrações de ghrelina foram menores que no grupo controle, apesar do hipercatabolismo, da hipoinsulinemia e da hiperglucagonemia, todas situações que fisiologicamente elevariam seus níveis, possivelmente devido à hiperglicemia marcante do momento; (b) durante o tratamento da CAD (T2 a T72): com redução gradual da glicemia até T24, elevação gradual da insulina, redução de glucagon, GH, cortisol e norepinefrina; nesse período, ocorreu elevação gradual da leptina após o início do tratamento com insulina, que atingiu níveis comparáveis ao GC no T72; redução da ghrelina (T4 menor que T72), provavelmente inibida pela hiperglicemia e por doses suprafisiológicas de insulina; e (c) após a resolução da CAD (TE): com hiperinsulinização; GH, cortisol e norepinefrina comparáveis ao GC, glucagon reduzido em relação ao GC, possivelmente supresso pelos altos níveis de insulina; as concentrações de leptina foram maiores que em T0 e comparáveis ao GC; os níveis de ghrelina, comparáveis ao diagnóstico e durante o tratamento da CAD, ainda significativamente menores que no GC, provavelmente influenciados pela hiperglicemia, hiperinsulinemia e baixos níveis de glucagon. CONCLUSÕES: as concentrações de leptina diminuídas ao diagnóstico de CAD tornam-se semelhantes em pacientes com DM1 estáveis em relação a indivíduos saudáveis, podendo ser um marcador de hipercatabolismo. As concentrações de ghrelina permaneceram baixas durante todo o estudo em pacientes diabéticos, independentemente da descompensação / INTRODUCTION: The role of glucoregulatory hormones in diabetic ketoacidosis have been investigated since 1970-80s and the elevation of growth hormone, cortisol and norepinephrine reduce the sensitivity to insulin. Leptin and Ghrelin have more recently been shown to regulate glucose and insulin metabolism; however, their functions in DKA are still controversial. The aims of this study were to analyze leptin, ghrelin and their relationships with other glucoregulatory hormones on diagnosis of diabetic ketoacidosis, during the first 72 hours of treatment and after recovery compared with healthy subjects. METHODS: We examined 25 DKA episodes in 22 patients who were admitted to the pediatric emergency department of a tertiary hospital in São Paulo, Brazil, from March 2010 to July 2013. These episodes were managed with fluids and electrolytes replacement and intermittent subcutaneous fast-acting insulin analogues. Samples for blood glucose, insulin, leptin, ghrelin, GH, cortisol, and catecholamines were obtained on admission (T0), during treatment (after 2, 4, 6, 12, 24 and 72 hours) and after discharge (TS). The control group (CG) was comprised by 21 healthy subjects, who submitted a single blood sample. Data were analyzed by ANOVA or Kruskal-Wallis to compare continuous variables during treatment, student t-test or Mann Whitney for comparisons between patients and controls, and Pearson or Spearman correlations between variables; p < 0.05 was considered to be significant. RESULTS: we observed three distinct phases: (a) on diagnosis of DKA (T0) where hyperglycemia, insulinopenia, and elevated glucoregulatory hormones prevail; leptin concentrations were lower than CG at this moment, probably related to energy insufficiency, hypercatabolic state, and elevated glucoregulatory hormones; ghrelin concentrations were lower than CG at this moment, despite hypercatabolism, hypoinsulinemia and hyperglucagonemia, situations that physiologically would increase them, possibly related to marked hyperglycemia at T0; (b) during DKA treatment (T2 to T72): with gradual reduction of blood glucose until T24, gradual rise of insulin; reduction of glucagon, GH, cortisol and norepinephrine. Leptin levels rises gradually after the start of insulin treatment and is comparable to control group at T72; reduction of ghrelin (T4 lower than T72), possibly inhibited by hyperglycemia and supraphysiological doses of insulin, all lower than CG; and (c) After DKA (TS), in an outpatient setting: with marked hyperinsulinization, GH, cortisol and norepinephrine were comparable to CG. Glucagon was lower than CG, possibly suppressed by high insulin levels; leptin was higher than T0 and comparable to CG; ghrelin levels were comparable to all samples during DKA treatment, and still significantly lower than CG, probably influenced by hyperglycemia, hyperinsulinemia and low glucagon levels. CONCLUSIONS: Low leptin levels were a marker of hypercatabolic state, with normalization of its concentrations with DKA resolution. Ghrelin was low in diabetic patients independent of metabolic derangements
213

ADRENERGIC STIMULATION IN ACUTE HYPERGLYCEMIA: EFFECTS ON CELLULAR AND TISSUE LEVEL MURINE CARDIAC ELECTROPHYSIOLOGY

Thyagarajan, Sridevi 01 January 2018 (has links)
Cardiovascular complications associated with elevated levels of glucose in the blood (Hyperglycemia, HG) is a growing health concern. HG is known to be associated with a variety of cardiovascular morbidities including higher incidence of electrical disturbances. Although effects of chronic HG have been widely investigated, electrophysiological effects of acute hyperglycemia are relatively less known. Further, hyperglycemic effects on adrenergic response is not widely investigated. We used excised ventricular tissues from mice to record trans-membrane potentials during a variety of pacing protocols to investigate cellular/tissue level electrophysiological effects of acute hyperglycemia and adrenergic stimulation (1µM Isoproterenol, a β-adrenergic agonist). A custom program was used to compute action potential durations (APD), maximal rates of depolarization (dv/dtmax), and action potential amplitudes (APA) from the recorded trans-membrane potentials. From these computed measures, electrical restitution and alternans threshold were quantified. Restitution was quantified using the Standard Protocol (SP; basic cycle length BCL= 200ms), Dynamic Protocol (DP; 200-40ms or until blockade) and a novel diastolic interval (DI) control protocol with Sinusoidal Changes in DI. Results from 6 mice show that acute hyperglycemia causes prolongation of the APD. Effects of adrenergic stimulation during acute hyperglycemia were partially blunted compared with non-hyperglycemic state, i.e. hyperglycemia minimized the decrease in APD that was produced by adrenergic stimulation. Similar, but less consistent (across animals) effects were seen in other electrophysiological parameters such as alternans threshold. These results show that acute hyperglycemia may itself alter cellular level electrophysiology of myocytes and importantly, modify adrenergic response. These results suggest that in addition to long term re-modeling that occurs in diabetes, acute changes in glucose levels also affect electrical function and further may contribute to systemically observed changes in diabetes by blunting adrenergic response. Therefore, further investigation into the electrophysiological effects of acute changes in glucose levels are warranted.
214

Index of Central Obesity as a Parameter to Evaluate Metabolic Syndrome for White, Black, and Hispanic Adults in the United States

Griesemer, Rebecca Lynn 25 July 2008 (has links)
Metabolic syndrome is a cluster of disorders including central obesity, hypertension, dyslipidemia, and hyperglycemia. Today's metabolic syndrome definitions identify central obesity by waist circumference (WC) measurements. A recent pilot study suggests that cut-points derived from a waist-to-height ratio (WHtR), or Index of Central Obesity (ICO), is a more accurate measurement of central obesity. This study compared the association between the metabolic syndrome components and central obese parameters (ICO and WC) among the white, black, and Hispanic adults in the United States. The subjects' data was obtained from the 2005-2006 National Health and Nutrition Examination Survey. ICO was highly correlated with metabolic syndrome components among white subjects and the least correlated in Hispanic subjects. Multivariate logistic regression analysis did not indicate that ICO was a better parameter for metabolic syndrome than WC. Other WHtR cut-points may be more sensitive in predicting metabolic syndrome components than the values used in this study.
215

Dissection du rôle fondamental de l'hyperglycémie sur la morphogenèse rénale

Tran, Stella Lê Minh January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
216

Drug use and side effects in the elderly : findings from the Kungsholmen Project /

Passare, Galina, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 5 uppsatser.
217

The association between glycaemic control and lifestyle habits in adults with Type 2 Diabetes Mellitus attending selected private health care practices in Thabazimbi, Limpopo Province.

Carstens, Maryke 12 1900 (has links)
Thesis (MNutr)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Introduction: Intensive lifestyle intervention in people with Type 2 Diabetes Mellitus (T2DM) is associated with weight loss, significant reductions in HbA1c% and a reduction in cardiovascular disease risk factors. Small towns unfortunately experience a deficit of dieticians, thus limiting access to lifestyle intervention. Furthermore, a limited number of South African studies have evaluated the effect of dietary habits, anthropometric status, activity level (AL) and dietician-led medical nutrition therapy (MNT) on glycaemic control in patients with T2DM. This study thus aimed to identify the association between glycaemic control and lifestyle habits in adults with T2DM living in Thabazimbi. The role of the dietician with regard to optimal glycaemic control was also investigated with great interest. Methods: Individuals (>18 years) with T2DM who had a recent HbA1c test result and no acute infection/illness were included in the study over a 7 month recruitment period. Weight, height and waist circumference were measured, AL and dietetic contact evaluated, and dietary habits assessed by means of a structured questionnaire. Six home-measured post-prandial glucose (PPG) measurements and HbA1c% were used to evaluate glycaemic control. Results: A total of 62 (59.7% males) patients were included. The mean age was 60.13 ±10.85 years and mean T2DM disease duration was 121 ±96.56 months. Only 6.45% of participants had a normal Body Mass Index classification. Most (90.32%) participants had a substantially increased waist circumference (WC). Half of the participants had a sedentary/low AL, whilst 48.39% had an active/moderately active AL. Almost all (95%) participants indicated it was necessary for persons with DM to consult a dietician for MNT, however only 63% of participants actually consulted one. Mean dietary compliance was 74.53 ±10.93%. The average HbA1c% and PPG of participants were respectively 7.50 ±1.62% and 8.90 ±3.21mmol/l. A significant negative association (r=-0.31; p=0.02) was found between HbA1c% and percentage dietary compliance. The number of dietetic sessions completed and average PPG were also significantly [(r=0.40; p=0.001), (r=-0.34; p=0.01)] associated with percentage dietary compliance. In turn PPG had a significant positive (r=0.30; p=0.02) association with DM disease duration. Both the good HbA1c and good PPG control groups had significantly (p=0.01, p=0.04) better dietary habits than the poor HbA1c and PPG control groups. When compared to the poor PPG group, the good PPG group made significantly (p=0.04) better dietary decisions with regard to the main meal’s carbohydrate quality and quantity. Body Mass Index, WC, AL and extent of dietetic contact didn’t play a significant role in the glycaemic classification (good vs. poor) of participants. Conclusion: The longer T2DM is present, the worse PPG control becomes. Optimal dietary habits play a significant positive role in both the long- and short term glycaemic control of people with T2DM in Thabazimbi. The choice and portion size of the main meal’s carbohydrates has been identified to be the most important dietary role-player in the glycaemic control of this study population. This study also shows that if individuals with DM spend enough time with a dietician, it could potentially contribute to better dietary compliance and subsequent better glycaemic control. / AFRIKAANSE OPSOMMING: Inleiding: Intensiewe leefstyl intervensie onder diegene met Tipe 2 Diabetes Mellitus (T2DM) word geassosieer met gewigsverlies, beduidende verlaging in HbA1c% asook ’n vermindering in verskeie kardiovaskulêre-siekte risiko faktore. Plattelandse dorpies beleef egter ’n tekort aan dieetkundiges, wat gevolglik toegang tot leefstyl intervensie beperk. Daar is ook ’n beperkte hoeveelheid Suid-Afrikaanse studies wat die impak van eetgewoontes, antropometriese status, aktiwiteitsvlak en dieetkundige-begeleide dieetterapie op glisemiese beheer in T2DM pasiënte evalueer. Die doel van die studie was dus om die verband tussen glisemiese beheer en leefstyl gewoontes in volwassenes met T2DM in Thabazimbi te bepaal. Die rol van die dieetkundige met betrekking tot optimale glisemiese beheer was ook met groot belangstelling nagevors. Metodes: Diegene (>18 jaar) met T2DM wat oor ’n onlangse HbA1c toets uitslag beskik het en nie enige akute siektes/infeksie gehad het nie, is oor ’n 7 maande werwingsperiode ingesluit. Gewig, lengte en middel-omtrek was gemeet, aktiwiteitsvlak en dieetkundig-kontak bepaal, en eetgewoontes geassesseer m.b.v. ’n gestruktueerde vraelys. Ses tuis-bepaalde na-ete bloedsuiker lesings en HbA1c% was gebruik om glisemiese beheer te evalueer. Resultate: Twee-en-sestig (59.7% mans) pasiënte het aan die studie deelgeneem. Die gemiddelde ouderdom was 60.13 ±10.85 jaar en die gemiddelde T2DM duurte 121 ±96.56 maande. Slegs 6.45% van die deelnemers het ’n gesonde Liggaam-Massa-Indeks gehad. Meeste (90.32%) deelnemers se middel-omtrek was ook ruimskoots verhoog. Die helfte van die deelnemers het ’n passiewe/lae aktiwiteitsvlak gehad, terwyl 48.39% ’n aktief/matig-aktiewe aktiwiteitsvlak gerapporteer het. Amper al (95%) die deelnemers het aangedui dat mense met T2DM ’n dieetkundige moet raadpleeg vir dieetterapie. Slegs 63% van die deelnemers het egter werklik ’n dieetkundige vir diabetes dieetterapie geraadpleeg. Gemiddelde dieet-gehoorsaamheid was 74.53 ±10.93% en die gemiddelde HbA1c % en na-ete bloedsuiker vlakke van deelnemers was onderskeidelik 7.50 ±1.62% en 8.90 ±3.21mmol/l. Daar was ’n beduidende negatiewe verband (r=-0.31; p=0.02) tussen HbA1c % en persentasie dieet-gehoorsaamheid. ’n Beduidende verband was ook tussen persentasie dieet-gehoorsaamheid en die hoeveelheid voltooide dieetterapie sessies (r=0.40; p=0.001) asook die gemiddelde na-ete bloedglukose vlak (r=-0.34; p=0.01) geïdentifiseer. Na-ete bloedglukose het ook ’n beduidende positiewe (r=0.30; p=0.02) verband met die duurte van diabetes getoon. Beide die goeie HbA1c en goeie na-ete glukose groepe het beduidend (p=0.01, p=0.04) beter eetgewoontes as die swak HbA1c en swak na-ete glukose groepe gehad. Die goeie na-ete glukose groep het veral beduidend (p=0.04) beter dieet keuses m.b.t die hoofmaal se koolhidraat kwaliteit en kwantiteit gemaak. Lengte-Massa-Indeks, middel-omtrek, aktiwiteitsvlak en die mate van dieetkundige kontak het nie ’n beduidende rol in die glisemiese klassifikasie (goed teenoor swak) van deelnemers gespeel nie. Gevolgtrekking: Na-ete bloedsuiker beheer word al hoe slegter hoe langer T2DM teenwoordig is. Optimale eetgewoontes speel ’n beduidende positiewe rol in beide die lang- en kort-termyn glisemiese beheer van mense met T2DM in Thabazimbi. Die keuse en porsie grootte van die hoofmaal se koolhidrate blyk die belangrikste dieet rolspeler in die glisemiese beheer van die studie populasie te wees. Die studie dui ook aan dat as mense met T2DM genoeg tyd saam met ’n dieetkundige deurbring, dit moontlik kan bydra tot beter dieet-gehoorsaamheid en gevolglik beter glisemiese beheer.
218

Diabète, inflammation et stress oxydatif : impact sur la barrière hémato-encéphalique, la neurogenèse et la réparation cérébrale / Diabetes, inflammation and oxidative stress : impact on blood-brain barrier, neurogenesis and brain repair

Dorsemans, Anne-Claire 13 September 2018 (has links)
Le diabète de type 2 est une pathologie complexe et multifactorielle caractérisée par une hyperglycémie chronique et une résistance à l’insuline. Actuellement, le diabète de type 2 est une préoccupation majeure et mondiale de santé publique. Les objectifs de cette thèse étaient d’étudier l’impact de l’hyperglycémie (aiguë, récurrente et chronique) sur des modèles complémentaires in vivo (poisson zèbre et souris) à un niveau périphérique et central. L’hyperglycémie aiguë et/ou chronique chez le poisson zèbre a altéré l’expression génique des cytokines pro-inflammatoires du cerveau, a modulé l’expression des gènes impliqués dans l’établissement de la barrière hémato-encéphalique, a diminué la prolifération des progéniteurs neuronaux de la plupart des niches neurogéniques et a impacté les mécanismes de réparation du télencéphale. L’hyperglycémie récurrente a induit un prédiabète caractéristique chez la souris avec des altérations périphériques et centrales que la glycine a atténuées en partie. L’ensemble des résultats indique que l’hyperglycémie contribue aux dysfonctionnements observés dans le diabète au niveau de l’inflammation, du stress oxydatif, de la barrière hémato-encéphalique, de la plasticité neuronale et des processus neurogéniques, ainsi que des fonctions cognitives, et souligne le potentiel antidiabétique intéressant de la glycine. En complément de ces résultats de recherche, une mission d’enseignement orientée santé a été menée auprès d’étudiants universitaires. Cette approche holistique de la pathologie diabétique pourrait contribuer, à terme, à l’élaboration de programmes de prévention adaptés, de dépistages précoces et de thérapies efficaces. / Type 2 diabetes is a complex and multifactorial disease characterized by chronic hyperglycemia and insulin resistance. Type 2 diabetes is currently a major and worldwide public health issue. The main objectives of this thesis were to investigate the peripheral and central impact of hyperglycemia (acute, recurrent and chronic) in vivo on complementary models (zebrafish and mouse). In zebrafish, acute and/or chronic hyperglycemia modulated cerebral expression of pro-inflammaty cytokines, as well as expression of genes involved in blood-brain barrier establishment. It also reduced neural progenitor proliferation in main neurogenic niches and impaired brain repair mechanisms. In the mouse, recurrent hyperglycemia induced a characterized prediabetes with central and peripheral alterations partially alleviated by glycine. All results suggest that, hyperglycemia contributes to related diabetes dysfunctions, through inflammation and oxydative stress, on blood-brain barrier integrity, neural plasticity including neurogenesis, and cognitive functions, and highlights the antidiabetic potential of glycine. In addition, a health-oriented teaching mission has been undertaken on university students. This holistic approach on diabetic disease could help in establishing effective prevention programs, early screenings and efficient therapies.
219

Efeito do tratamento com metformina sobre o desenvolvimento, potencial metastásico e vias de sinalização do câncer de endométrio in vitro

Machado, Amanda de Barros January 2017 (has links)
Endometriumkrebs ist eine der häufigsten gynäkologischen Malignomen weltweit und wird in einen Typ I eingeteilt, welcher östrogenabhängig ist, und in eine Typ-II-Östrogen-unabhängige Form. Typ I ist der häufigste Fall und kommt in etwa für 75% bis 85% aller diagnostizierten Fälle in Frage. Erhöhte Östrogenspiegel haben gezeigt, das Risiko von Gebärmutterkrebsentwicklung zu erhöhen, genauso wie Östrogen die Proliferation von Endometriumzellen stimuliert und die Apoptose hemmt. Die Insulinresistenz scheint eine zentrale Rolle in der endometrialen Karzinogenese zu spielen und darüber hinaus werden Erkrankungen mit Insulinresistenz, wie zum Beispiel das polyzystische Ovarialsyndrom (PCOS) und Adipositas, sowie Typ II-Diabetes mellitus (DM) als signifikantes Risiko angesehen, Faktoren für die Entwicklung und Progression von Typ-I-Endometrium-Krebs zu sein. Zusätzlich können PCOS-Patienten durch eine Fettleibigkeit in einem normoglykämischen Status eine unabhängige Insulin-Resistenz haben. In diesem Fall scheint die Hyperinsulinämie der fördernde Faktor zu sein, nicht nur für die Entwicklung als auch für die Tumorprogression.Aber auch erhöhte Blutzuckerspiegel tragen zum Wachstum und die Karzinogenese in Endometriumkarzinom bei und dienen als wichtige Verbindung zwischen dem beobachteten erhöhten Krebsrisiko bei Patienten mit Typ-II-DM. Die Behandlung mit einem Anti-Diabetikum, welches den Insulinspiegel senken kann, könnte einen allgemeinen Ansatz bieten gegen die Entwicklung von Krebs und zur Verringerung der Metastasierung. Das Ziel dieser Studie war es, die Wirkung einer 0,1 mM Metformin-Dosis auf das proliferative und metastatische Potential von Endometriumkrebszellen bewerten zu können, sowie die Analyse der Auswirkungen von kurz- und langfristigen Behandlungen auf intrazelluläre Signalwege der Endometriumkrebszellen.(Fortsetzung) (Fortsetzung)Ebenso soll der Zusammenhang der Entwicklung und der Progression von Krebszellen untersucht werden, wenn sie einer Umgebung mit unterschiedlichen Glucosekonzentrationen und hohen Insulinspiegeln ausgesetzt werden. Darüber hinaus ist eine endometriale dreidimensionale (3D) Cokultur zu standardisieren, für eine viabele Kultur bei 20 Tagen Kultivierung. Das proliferative Potential wurde unter Verwendung des CellTitle-Glo-Tests durchgeführt, und das metastatische Potential wurde unter Verwendung von Transwell-Migration und Invasion untersucht. Die mRNAExpression von MKI67, mTOR, NOTCH1, NOTCH3 und JAG1 Gene wurden durch real-time PCR gemessen. Die kumulative Populationsverdopplungsrate wurde durch das Replikationsverhalten einer Endometriumkrebszelllinie durchgehend von 20 Tagen nach einer Behandlungsdauer bestimmt. In allen Assays wurden die Zellen durch Medien mit normaler (5,5 mM) oder hoher (17 mM) Glucosekonzentration, sowie in verschiedenen Gruppen behandelt: Kontrolle, Insulin, Metformin und Insulin+Metformin. Das 3D-Kokulturmodell wurde unter Verwendung von endometrialen Primärzellen und einer Endometriumkrebszelllinie hergestellt, wobei die Modellkonstruktion durch Matrigel® als extrazelluläre Matrix verwendet wurde. In dieser Studie hemmte die 0,1 mM Metformin-Dosis die Insulinwirkung stark und verringerte die Fähigkeit der endometrialen Krebszelllinie, in einer hohen und normalen Glukoseumgebung zu migrieren und einzudringen.(Fortsetzung) (Fortsetzung) Auf das proliferative Potential wurde dieser Effekt nicht beobachtet, allerdings reagierte die relative Zellproliferation empfindlich auf Metformin im Bereich zwischen 1 und 5 mM, unabhängig von der vorliegenden Glucosekonzentration. In den intrazellulären molekularen Mechanismen wurde beobachtet, dass die hohe Glukosekonzentration eine optimale Umgebung für endometriale Krebszellen schafft, um einen aggressiveren Genotyp und eine Resistenz gegenüber Metformin während einer Langzeitbehandlung zu zeigen. Darüber hinaus blieb das endometriale 3DKokulturmodell über 20 Kulturtage lebensfähig. Daher zeigte sich, trotz der Endometriumkrebszellen, eine Resistenz gegenüber dem Metformin-Effekt, wenn sie einer hohen Glucoseumgebung ausgesetzt waren. Die 0,1 mM Metformin-Dosis war in der Lage, die Insulinwirkung zu hemmen und das metastatische Potential der Zellen zu verringern, was darauf hindeutet, dass Metformin klinisch in Verbindung mit Insulin wirkt, sowie die indirekten und direkten Effekte als potentieller Wirkstoff in der Krebstherapie eingesetzt werden könnten. / O câncer de endométrio é uma das neoplasias ginecológicas com maior incidência, classificado como tipo I, estrógeno dependente, e tipo II, estrógeno nãodependente. O tipo I é a forma mais comum, ocorrendo em torno de 75 – 85 % dos casos de câncer de endométrio. Altos níveis de estrogênio têm sido relacionados ao aumento do risco de desenvolvimento do câncer de endométrio, pois estimula a proliferação celular e inibe a apoptose. A resistência à insulina parece desempenhar um papel central nesta neoplasia, e as doenças associadas à resistência à insulina como obesidade, Diabetes Mellitus (DM) tipo II e Síndrome dos Ovários Policísticos (PCOS) também são consideradas fatores de risco significantes para o desenvolvimento e progressão do câncer de endométrio tipo I. Adicionalmente, pacientes com PCOS podem apresentar um quadro de resistência à insulina independente de obesidade, permanecendo em um estado glicêmico normal. Neste caso, a hiperinsulinemia isolada seria um fator tanto para a promoção, como também para a progressão do câncer. Entretanto, o aumento de níveis séricos de glicose, a hiperglicemia, também é considerada um fator independente para o desenvolvimento e progressão do câncer de endométrio sendo um elo crítico entre o aumento do risco do desenvolvimento de câncer observado em pacientes com DM tipo II Dessa forma, tratamento utilizando agentes insulino-sensibilizantes, que atuam diminuindo a resistência à insulina e consequentemente reduzindo seus níveis pode ser uma estratégia interessante para prevenir o câncer e reduzir a disseminação metastática. Os objetivos deste trabalho foram avaliar o efeito da dose de 0,1 mM de metformina sobre o potencial proliferativo e metastático das células de câncer de endométrio, assim como, avaliar o efeito do tratamento a curto e a longo prazo sobre vias de sinalização intracelular relacionadas ao desenvolvimento e progressão do câncer de endométrio quando exposta a um ambiente com diferentes concentrações de glicose e níveis elevados de insulina. Por fim, a padronização de um modelo tridimensional (3D) de cocultura de células de endométrio que permanecesse viável ao longo de 20 dias de cultivo. O potencial proliferativo foi determinado pelo método luminescente CellTitle Glo, e o potencial metastático pelo o ensaio transwell de migração e invasão. Análises de expressão do mRNA dos genes MKI67, mTOR, NOTCH1, NOTCH3 e JAG1 foram realizadas a partir da técnica de PCR em tempo real. O índice de duplicação populacional cumulativo das células determinou o comportamento de replicação da linhagem de câncer de endométrio ao longo do período de tratamento de 20 dias. Em todas os ensaios as células foram cultivadas em meio contendo concentrações normais (5,5 mM) ou altas (17 mM) de glicose, e divididas nos diferentes grupos de tratamento: controle, insulina, metformina e metformina associado a insulina. A padronização do modelo 3D de cocultura de células de endométrio foi realizado utilizando células primárias e células de linhagem de câncer de endométrio, a Matrigel® foi a matriz extracelular temporária utilizada para a construção do modelo. Neste estudo, a concentração de 0,1 mM de metformina inibiu a ação da insulina, diminuindo a habilidade de migração e invasão das células de câncer de endométrio independente da concentração de glicose presente no meio. Entretanto, este efeito não foi observado sobre o potencial proliferativo, sendo observada uma redução da proliferação das células de câncer de endométrio ao serem utilizadas concentrações maiores de metformina. Em relação aos mecanismos moleculares intracelulares, foi observado que na presença de altas concentrações de glicose as células de câncer de endométrio adquirem um genótipo mais agressivo e apresentam resistência ao efeito da metformina na dose de 0,1 mM durante o tratamento agudo. Além disso, foi possível a padronização de um modelo 3D de cocultura de células de câncer de endométrio que permanecesse viável ao longo dos 20 dias de cultivo. Contudo, apesar das células de câncer de endométrio apresentarem resistência ao efeito da metformina na presença de altas concentrações de glicose, a dose de 0,1 mM foi capaz de inibir o efeito da insulina e diminuir o potencial metastático dessas células, sugerindo que a metformina ao atuar clinicamente em combinação com seus efeitos indiretos e diretos pode ser um potencial agente adjuvante na terapia contra o câncer. / Endometrial cancer is one of the most common gynecological malignancies worldwide and is classified into a type I, which is estrogen-dependent, and a type II estrogen-independent form. The type I is the most common, accounting to 75%-85% of all cases of endometrial cancer. Elevated estrogen levels have been shown to increase the risk of endometrial cancer development, as estrogen stimulates endometrial cell proliferation and inhibits apoptosis. The insulin resistance seems to play a central role in endometrial carcinogenesis, furthermore, diseases associate with insulin resistance, as seen in polycystic ovary syndrome (PCOS), and obesity, as well as type II diabetes mellitus (DM) are considered as significant risk factors for the development and progression of type I endometrial cancer. Additionally, PCOS patients may have an insulin resistance independent of obesity remaining in a normoglycemic status. At this case, the hypeinsulinemia seems to be the promoter factor not only for the development but also for the cancer progression. However, also increased blood glucose levels are contributing to the growth and carcinogenesis in endometrial cancer and are acting as a critical link between the observed increased cancer risk in patients with type II DM. Therefore, the treatment with insulin-sensitizing agents that act through reducing insulin levels, could offer a general approach to prevent the development of cancer and reduce metastasis The aim of this study was to evaluate the effect of 0.1 mM metformin dose on the proliferative and metastatic potential of endometrial cancer cells, as well as, analyze the effects of short and long-term treatment on intracellular signaling pathways related to endometrial cancer development and progression when exposed to an environment with different glucose concentrations and high insulin levels. Additionally, the endometrial three-dimensional (3D) coculture standardization to remain viable over 20 culture days. The proliferative potential was performed by using CellTitle Glo assay, and the metastatic potential was performed by using transwell migration and invasion assay. The mRNA expression of MKI67, mTOR, NOTCH1, NOTCH3 and JAG1 genes were measured by real time PCR. The cumulative population doubling rate was evaluated to determine the replication behavior of an endometrial cancer cell line throughout 20 days of treatment period. In all assays the cells were cultured in medium containing normal (5.5 mM) or high (17 mM) glucose concentration, and treated in different groups: control, insulin,metformin or combined treatment The 3D coculture model was established by using endometrial primary cells and an endometrium cancer cell line, to the model construction Matrigel® was used as an extracellular matrix. In this study, the 0.1 mM metformin dose potently inhibited the insulin action, decreasing the ability of the endometrial cancer cell line to migrate and invade in a high and normal glucose environment. On the proliferative potential this effect was not observed, however, relative cell proliferation sensitivity to metformin was observed in the range between 1 and 5 mM regardless of the present glucose concentration. In the intracellular molecular mechanisms, it was observed that the high glucose concentration creates an optimal environment for endometrial cancer cells to exhibit a more aggressive genotype and resistance to metformin during a long-term treatment. Moreover, the endometrial 3D coculture model remained viable throughout 20 culture days. Therefore, despite of endometrial cancer cells show resistance to the metformin effect when exposed to high glucose environment, the 0.1 mM metformin dose was able to inhibit the insulin action and decrease the metastatic potential of the cells, suggesting that metformin is acting clinically in combination with indirectly and direct effects could emerge as a potential agent in cancer therapy.
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Knowledge of patients and family members regarding diabetes mellitus and its treatment

Shilubane, Hildah N. 30 November 2003 (has links)
Diabetes mellitus is a chronic disease affecting millions of people worldwide. The degenerative changes caused by diabetes can, however, be controlled through the correct treatment. The outcome of diabetes mellitus depends mainly on the patient's self-management. Health professionals therefore have a major responsibility to assist patients to acquire the essential knowledge, skills and attitudes for self-management. The purpose of this study was to identify diabetic patients and family members' knowledge and views about diabetes mellitus and its treatment regimen. A quantitative descriptive survey design was used. Questionnaires were used to collect data from a convenient sample of diabetic patients and family members. Data was analysed by a computer program called Statistical Package for Social Sciences. Findings revealed that patients and family members lack adequate knowledge on diabetes mellitus and its treatment. Recommendations regarding the required information and assistance to be given to diabetic patients and their family members were formulated. / Health Studies / (MA (Health Studies))

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