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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.
141

Preventing Progression of End Stage Renal Disease: A Systematic Review of Patient-Provider Communication in Primary Care

Prieto, Roseanne January 2016 (has links)
Background: Chronic kidney disease (CKD) affects approximately 26 million individuals in the United States and is a top priority in the objectives for Healthy People 2020. Despite efforts to improve awareness, discussion of CKD is often minimal or ineffective in the primary care setting. This leads to a lack of patient awareness and knowledge of self-care skills to prevent or slow progression of the disease. A lack of communication of has been attributed to the provider's lack of confidence and knowledge to discuss CKD and to avoid unnecessary stress. Purpose: The purpose of the DNP project is to provide a systematic review of patient-provider communication processes used to influence self-management or behavioral change in primary care and propose a tool to enhance communication and slow progression of CKD. Methods: A systematic review was conducted following the method guidelines of the Cochrane Collaboration. Six electronic databases were searched. Inclusion criteria were adult humans, primary research studies, systematic and literature reviews, focus on communication of self-management or behavioral change strategies, primary outcomes of improving self-management and/or patient outcomes and availability of full-text online or by request. Outcomes: Of the 5765 articles initially identified, 28 studies met inclusion criteria. The studies revealed a lack of evidence directed towards CKD and communication was not directly addressed in a majority of the studies. Interventions most successful in improving patient outcomes were individualized, elicited collaboration or interaction with the patient and provider, were motivational or encouraging and aided in barrier identification and problem solving. A communication tool was developed from the evidence in order to stimulate more meaningful conversation between the patient and provider.
142

Exercise in chronic kidney disease : impact on immunity and inflammation

Campos-Pereira-Da-Cruz-Viana, Joao January 2011 (has links)
Chronic kidney disease (CKD) is associated with a complex state of immune dysfunction characterised by immune depression, which predisposes CKD patients to infections, and by immune activation resulting in inflammation, which is associated with cardiovascular disease among these patients. It has been suggested that regular moderate exercise may enhance immune function and exert anti-inflammatory effects. However, such effects are still unclear in CKD. Therefore, we investigated the effects of acute and regular (1-month and 6-months) moderate intensity aerobic exercise (walking) on measures of immunity and inflammation in pre-dialysis CKD patients. A single bout of walking exercise induced an overall immune and inflammatory response that was comparable to that observed in healthy individuals, with no indication of harmful effects to patients underlying state of immune dysfunction. Acute exercise induced a normal pattern of mobilisation of immune cells. Concerning immune cell function, acute exercise had no effect on T lymphocyte and monocyte activation, while it actually improved neutrophil responsiveness to a bacterial challenge in the recovery period. In addition, acute exercise induced a systemic anti-inflammatory environment, evidenced by the marked elevation in plasma IL-10 levels after exercise, which was most likely mediated by the observed increase in plasma IL-6 levels. Regular walking exercise exerted anti-inflammatory effects, with no apparent detrimental effects to patients immune and inflammatory status. Regular exercise led to improvements in the systemic inflammatory status (ratio of pro-inflammatory IL-6 to anti-inflammatory IL-10 cytokine levels) that were accompanied, and most likely mediated, by the observed down-regulation of T lymphocyte (only evident at 6-months) and monocyte activation. In addition, a reduction in IL-6 production in PBMC and whole blood cultures was also observed (only assessed at 1-month). Regular exercise had no effect on circulating immune cell numbers and neutrophil degranulation responses. These findings provide compelling evidence that walking exercise is safe from an immune and inflammatory perspective and has the potential to be an effective anti- inflammatory therapy in pre-dialysis CKD patients.
143

Μεταβολή των λεμφοκυτταρικών τύπων στη νεφρική νόσο

Μαρινάκη, Ελένη 11 October 2013 (has links)
Κάθε χρόνο τα άτομα που υποφέρουν από κάποιας μορφής νεφρική νόσο αυξάνονται παρά τις εξελίξεις στον τομέα της ιατρικής. Έχει παρατηρηθεί ότι η νεφρική νόσος, στις περισσότερες περιπτώσεις μπορεί να εξελιχθεί σε νεφρική ανεπάρκεια, είτε με πιο αργούς είτε με πιο γρήγορους ρυθμούς. Η νεφρική ανεπάρκεια αντιμετωπίζεται είτε με αιμοκάθαρση είτε με μεταμόσχευση. Το ανοσοποιητικό σύστημα διαδραματίζει σημαντικό ρόλο τόσο στην αντιμετώπιση όσο και στη πρόοδο των διάφορων μορφών νεφρικής νόσου. Ωστόσο, οι διάφοροι λεμφοκυτταρικοί τύποι, και ιδιαίτερα αυτοί της φυσικής ανοσίας, δεν έχουν μελετηθεί ιδιαίτερα και πολλές φορές από τις λίγες μελέτες που υπάρχουν προκύπτουν αντικρουόμενα αποτελέσματα. Η μελέτη μας επικεντρώθηκε στα Τ, στα ΝΚ και στα ΝΚ-Τ λεμφοκύτταρα. Επιλέξαμε να ερευνήσουμε αρχικά και τελικά στάδια νεφρικής νόσου. Έτσι οι ασθενείς κατηγοριοποιούνται σε τρεις ομάδες: ασθενείς με σπειραμαρονεφρίτιδα (αρχικό στάδιο), ασθενείς που υποβάλλονται σε αιμοκάθαρση και μεταμοσχευμένοι ασθενείς (τελικά στάδια). Σε κάθε πείραμα γίνεται σύγκριση με μια ομάδα ελέγχου (control, που αποτελείται από υγιή άτομα). Στην περίπτωση της σπειραματονεφρίδας παρατηρήθηκαν φυσιολογικά ποσοστά των λεμφοκυτταρικών τύπων και της έκφρασης του NKG2D υποδοχέα. Παρατηρήθηκε, όμως, αυξημένη έκφραση του TNF-α. Στην περίπτωση της αιμοκάθαρσης αν και παρατηρήθηκε μειωμένο ποσοστό ΝΚ και Τ κυττάρων, βρέθηκε ότι παρουσιάζουν αυξημένη κυτταροτοξικότητα και λειτουργικότητα. Αυτό φαίνεται και από την αύξηση στην έκφραση του CD107α και από την αύξηση στη συγκέντρωση του TNF-α. Όσον αφορά τα ΝΚ-Τ κύτταρα, αν και το ποσοστό τους είναι φυσιολογικό, εμφανίζουν αυξημένη έκφραση του υποδοχέα NKG2D. Τέλος, όσον αφορά την ομάδα των μεταμοσχευμένων ασθενών, δεν παρατηρήθηκε μεταβολή στο ποσοστό των Τ και των ΝΚ-Τ κυττάρων. Όταν όμως οι ασθενείς κατηγοριοποιούνται με βάση την φαρμακευτική αγωγή, το ποσοστό των ΝΚ-Τ κυττάρων είναι αυξημένο σε ασθενείς που τους χορηγείται κυκλοσπορίνη. Επίσης, η έκφραση του υποδοχέα NKG2D είναι φυσιολογική και στις δύο κατηγορίες λεμφοκυττάρων. Από την άλλη, αν και το ποσοστό των ΝΚ κυττάρων μειώνεται, αυτά εμφανίζουν φυσιολογική λειτουργικότητα και κυτταροτοξικότητα, όπως φαίνεται από τη φυσιολογική έκφραση του NKG2D υποδοχέα, της πρωτεΐνης CD107α και του TNF-α. / Every year, people who suffer from some form of kidney disease are increasing despite advances in medicine. It has been observed that the kidney disease, in most cases might progress to renal failure, either slower or faster. The renal failure is treated either by hemodialysis or renal transplantation. The immune system plays an important role in the treatment and in the progression of various forms of renal disease. However, the various types of lymphocytes, and especially those of innate immunity have not been widely studied and often the few studies that exist result in conflicting results. Our study focused on T, NK and NK-T lymphocytes. We chose to investigate initial and final stages of renal disease. Patients were categorized into three groups: patients with glomerulonephritis (initial stage), patients on dialysis and transplanted patients (final stages). In each experiment patients were compared with a control group consisting of healthy individuals. In the case of glomerulonephritis, we observed normal percentages of the lymphocyte population examined and normal expression of the NKG2D receptor, as well as increased expression of TNF-α. In the case of hemodialysis, NK and T cell percentages were reduced, while NK cells exhibited enhanced cytotoxicity and functionality. This was shown by the increase in the expression of CD107α and by the increase in the concentration of TNF-α. Regarding the NK-T cells, although their percentage was normal, they showed increased expression of NKG2D receptor. Finally, concerning the group of transplanted patients, no change was observed in the percentage of T and NK-T cells. However, when patients were categorized based on the medication, the percentage of NK-T cells was increased in patients receiving cyclosporine. In addition, the expression of NKG2D receptor was normal on T and NK-T cells. On the other hand, although the percentage of NK cells was reduced, those cells exhibited normal functionality and cytotoxicity, as shown by the normal expression of NKG2D receptor, CD107α protein and TNF-α.
144

Cardiovascular disease and diabetes or renal insufficiency : the risk of ischemic stroke and risk factor intervention

Jakobsson, Stina January 2015 (has links)
Background In patients with diabetes mellitus (DM) or chronic kidney disease (CKD), established cardiovascular disease (CVD) is associated with an increased risk of recurrent events and poor outcome. Ischemic stroke after an acute myocardial infarction (AMI) is a devastating event that carries high risks of decreased patient independence and death. Among patients with DM or CKD, the risk of an ischemic stroke within a year following an AMI is not known. Improved risk factor control is required to reduce the likelihood of CVD recurrence. Guidelines recommend target lipid profile and blood pressure values; however, data show that these targets are often not met. Therefore, there remains an urgent need for improved cardiovascular secondary preventive follow- up. Aims The aims of the present studies were to define trends in the incidence and predictors of ischemic stroke after an AMI in patients with DM or CKD. Furthermore to assess whether secondary preventive follow-up with nurse-based telephone follow-up including medication titration after CVD improves risk factor values in patients with DM or CKD and to investigate if this method performs better than usual care to implement a new treatment guideline in diabetic patients. Methods To assess the risk of post-AMI ischemic stroke, patient data were obtained from the Swedish Register of Information and Knowledge about Swedish Heart Intensive Care Admissions (RIKS-HIA). In separate studies, we compared a total of 173 233 AMI patients with and without DM, and 118 434 AMI patients with and without CKD. Within the nurse-based age-independent intervention to limit evolution of disease (NAILED) trial, we investigated a nurse-based cardiovascular secondary preventive follow-up protocol. Patients with acute coronary syndrome, stroke, or transient ischemic attack were randomized to receive either nurse-based telephone follow-up (intervention) or usual care (control). Low-density lipoprotein (LDL-C) levels and blood pressure (BP) were measured at 1 month (baseline) and 12 months post- discharge. Intervention patients with above-target baseline values received medication titration to achieve treatment goals, while the measurements for control patients were forwarded to their general practitioners for assessment. We calculated the changes in LDL-C level and BP between baseline and 12 months post-discharge, and compared  these changes between 225 intervention patients and 215 control patients with concurrent DM or CKD. During the course of the NAILED trial, new secondary preventive guidelines for DM patients were released, including a new LDL-C target value. To assess adherence to the new guidelines within the NAILED trial, we compared LDL-C levels in the 101 intervention patients and 100 control patients with DM. Results Ischemic stroke after AMI The rates of ischemic stroke within one-year after admission for an AMI decreased over time, from 7.1% in 1998–2000 to 4.7% in 2007–2008 among DM patients, and from 4.2% to 3.7% during the same time periods for non-diabetic patients. Lower stroke risk was associated with percutaneous coronary intervention (PCI) and initiation of secondary preventive treatments in-hospital. In-hospital ischemic stroke occurred in 2.3% of CKD patients and 1.2% of non-CKD patients, with no change in these incidences over time. The rates of one-year post- discharge ischemic stroke decreased between 2003–2004 and 2009–2010 from 4.1% to 2.5% among CKD patients, and from 2.0% to 1.3% among non-CKD patients. Lower rates of post-discharge stroke were associated with PCI and statins. Cardiovascular secondary preventive follow-up Among DM and CKD patients with above-target baseline values in the NAILED trial, the median LDL-C value at 12 months was 2.2 versus 3.0 mmol/L (p<0.001) and median systolic BP was 140 versus 145 mmHg (p=0.26) for intervention and control patients, respectively. Before the guideline change, 96% of the intervention and 70% of the control patients reached the target LDL-C value (p<0.001). After the guideline change, the corresponding respective proportions were 65% and 36% (p<0.001). Conclusion Ischemic stroke is a fairly common post-AMI complication among patients with DM and CKD. This risk of stroke has decreased during recent years, possibly due to the increased use of evidence-based therapies. Compared with usual care, cardiovascular secondary prevention including nurse-based telephone follow-up improved LDL-C values at 12 months after discharge in patients with DM or CVD, and led to more efficient implementation of new secondary preventive guidelines.
145

Utilization patterns and economic impact of IV iron and Erythropoiesis Stimulating Agents in Chronic Kidney Disease patients: A multi-hospital study

Joshi, Avani 01 October 2010 (has links)
Background: Chronic kidney disease (CKD) affects approximately 20 million Americans and is the cause of significant morbidity and mortality. Anemia, common in CKD, develops early in the disease process. It contributes to increased risk of cardiovascular disease, hospitalization, mortality, and diminishes health-related quality of life. Intravenous iron and Erythropoiesis Stimulating Agents (ESAs) are recommended for anemia management in CKD. The utilization patterns of IV iron and ESA, and their impact on hospital costs and length of stay merits investigation. Objectives: There were five general objectives of this investigation. The rate and extent of utilization of IV iron in anemic CKD patients was quantified across teaching hospitals in the US. Patient characteristics of those receiving IV iron and ESA and ESA alone were evaluated in detail. Predictors of IV iron and ESA use were determined. The impact of IV iron and ESA use was examined separately for total hospital costs and length of stay (LOS) while adjusting for confounding. Methods: This is a retrospective cohort analysis within the University Health System Consortium data warehouse. Eligible patients are those who were admitted to a hospital and received either IV iron and ESA or both at least once during the period of January 1, 2006, and December 31, 2008. Inclusion criteria include age > 18 years old with a primary or secondary diagnosis of CKD. The exposure of interest was IV iron and ESA therapy, and the outcome was the difference in total hospital costs and length of stay between patients only on ESA, and those on ESA and IV iron. A clustered binomial logistic regression using the GEE methodology was used to identify predictors of IV iron utilization. Propensity scores were used to control for confounding. A generalized estimating equations (GEE) model using a gamma distribution and log link was used to determine the adjusted hospital cost and length of stay for the IV iron and ESA and ESA alone therapy groups. Results: During the study period, 82,947 patients met all the inclusion and exclusion criteria. Of the 82,947 CKD patients on ESA therapy, only 8% (n = 6678) patients were on IV iron supplementation. Age, race, primary payer, admission status, severity of illness, dialysis status and physician specialty were identified as strong predictors of IV iron use in CKD patients. According to the multivariate model, the overall mean hospital cost for all 82,947 patients was $31,674. For patients using both IV iron and ESA (n=6678), mean costs were $34,756 compared to $31,404 for ESA users alone (n=76,269) – a difference of $3,352. The overall mean LOS for all patients was 9.75 days. For those using IV iron, the LOS was 10.71 days, and for those only using ESA, the LOS was 9.66 days– a difference of approximately 1 day. Conclusions: This inquiry is the first large multi-center investigation to quantify the impact of IV iron and ESA use on total hospital costs and LOS. Our investigation showed significant reduction in ESA doses with the use of IV iron supplementation, however, the overall prevalence of IV iron usage was low. Intravenous iron users were associated with a higher total hospital cost and longer length of stay than ESA users.
146

Histoire naturelle de la maladie rénale : Analyse des facteurs physiopathologiques et évaluation pronostique de l’insuffisance rénale terminale et de ses complications / Natural history of chronic kidney disease : Analysis of pathophysiological and prognostic factors of renal failure and its complications

Duranton, Flore 17 December 2013 (has links)
L'insuffisance rénale chronique (IRC) et son stade terminal sont associés à diverses complications, parmi lesquelles de nombreuses modifications du milieu intérieur : urémie, anémie, hyperparathyroïdie, rétention urémique… Les taux d'urée plasmatique ont longtemps été utilisés comme critère diagnostique de l'IRC, malgré l'absence de caractéristiques essentielles à un tel marqueur. Ces caractéristiques ont été discutées au regard de l'utilisation historique des déterminations d'urée. La caractérisation des altérations plasmatiques des patients en IRC est essentielle à la compréhension de la maladie et de leur lien avec la morbi-mortalité. Nous avons alors étendu notre champ d'intérêt à l'ensemble des solutés de rétention urémique, et sommes parvenus à identifier 56 nouveaux solutés à partir des études cliniques récemment publiées. L'évaluation diagnostique s'est poursuivie par l'étude des concentrations plasmatiques et urinaires en acides aminés et de leur association avec le stade d'IRC et ses complications, permettant alors la génération d'hypothèses sur l'origine métabolique de ces altérations. D'autre part, la mise en place d'une méta-analyse à montré une réduction du risque de décès chez les patients traités par dérivés de la vitamine D. La correction des comorbidités (hypovitaminose, perturbations du métabolisme phosphocalcique) et d'autres effets néphroprotecteurs expliqueraient ces bénéfices. Enfin, l'évaluation du protéome urinaire et du score CKD273 qui en résulte s'est avérée très intéressante pour l'identification des patients à risque de progresser, ce qui est un enjeu de santé publique. Ces travaux d'analyse bibliographique et de recherche clinique s'intègrent dans une volonté d'amélioration de la caractérisation de l'IRC et de l'évaluation de sa progression dans le but de prévenir ses complications. Ils sont le socle d'un projet plus large d'observation et d'analyse des caractéristiques des patients en IRC et de leur évolution. / Chronic kidney disease (CKD) and end-stage renal disease (ESRD) are associated with various complications, many of which occur within the internal environment: uremia, anemia, hyperparathyroidism, uremic retention… Plasma urea concentrations have long been used as a diagnostic criterion of CKD, despite the absence of some key characteristics. We discussed these features with regards to the historical uses of urea determinations. It is essential to characterize the plasma changes which occur in CKD to understand the disease and the relationship with comorbidities. We expanded our focus to all of uremic retention solutes, and identified 56 new solutes from recently published clinical studies. The study of plasma and urinary concentrations of amino acids and their association with CKD stage and complications further extended the study of CKD diagnosis, and allowed to generate hypotheses on the metabolic origin of these alterations. On the other hand, by meta-analysis, we showed a reduced risk of death in patients treated with vitamin D derivatives. Correcting comorbidities (hypovitaminosis, disturbances of bone and mineral metabolism) and other renoprotective effects may explain these benefits. Finally, the determination of the urinary proteome and the resulting CKD273 score was proved to be very useful for identifying patients at risk of progression, which is a public health issue. This work based on clinical research and literature analyses is part of an effort to improve the characterization of CKD and the evaluation of progression in order to avoid complications. It is the basis for a wider observational project: analyzing the characteristics of CKD patients and their changes over time.
147

The role of SERPINA3 in the pathogenesis of kidney disease

Heilig, Elysia Othelia 12 June 2019 (has links)
Chronic kidney disease (CKD), defined as a decrease in renal function, is a global issue. The treatment of CKD and its comorbidities imparts a costly burden on the American healthcare system, therefore the need for therapeutics that prevent the progression of chronic kidney disease is urgent. Microarray studies have shown that the serine protease inhibitor clade A member 3 (SERPINA3) is transcriptionally upregulated in kidney injury. SERPINA3 is an extracellular protease inhibitor that maintains the homeostasis of extracellular matrix proteins. Our lab hypothesizes that SERPINA3 might not only be a transcriptional biomarker for kidney injury, but the SERPINA3 protein might act as a key upstream regulator in the advancement of renal inflammation and fibrosis. Our research characterizes the expression patterns of SERPINA3 in models of acute and chronic kidney injury through immunoblotting and immunohistochemistry. Our unilateral ureteral obstruction (UUO) model of chronic renal injury displays significant glomerular localization of SERPINA3. The adenine diet model of chronic kidney injury and the renal ischemic reperfusion injury (RIRI) model of acute kidney injury both display tubular upregulation of SERPINA3. The DOCA-salt hypertension model of chronic kidney injury was imposed on two strains of mice, C57BL/6 and 129/sv, both of which display tubular and glomerular upregulation of SERPINA3. However, the C57BL/6 strain, which is known for its resistance to glomerular sclerosis, displays higher renal localization of SERPINA3 when exposed to DOCA-salt hypertension, than does the 129/sv strain. In conclusion, our data suggests that SERPINA3 protein is upregulated in both acute and chronic kidney injury. The role of SERPINA3 in these models remains unknown, however, our lab theorizes that SERPINA3 protein may be renoprotective in certain instances of kidney injury. Functional assays must be performed to elucidate the role of SERPINA3 in these models of kidney injury. Characterizing the function of SERPINA3 in chronic and acute kidney injury might aid in the development of novel therapeutics to prevent the advancement of CKD.
148

Influência da doença renal crônica e da hemodiálise na farmacodinâmica e farmacocinética dos isômeros do nebivolol em pacientes hipertensos / Influence of chronic kidney disease and hemodialysis on the pharmacodynamics and pharmacokinetics of nebivolol isomers in hypertensive patients

Neves, Daniel Valente 20 May 2013 (has links)
A doença renal crônica (DRC) está associada com inibição de sistemas enzimáticos e de transportadores de fármacos. O nebivolol, um bloqueador de terceira geração, seletivo para receptores 1 adrenérgicos e com atividade vasodiladora, é metabolizado principalmente por hidroxilação aromática dependente do CYP2D6, hidroxilação alicíclica e por glicuronidação. O estudo avalia a influência da DRC estágios 3 e 4 e da hemodiálise na farmacodinâmica e na farmacocinética dos isômeros do nebivolol. Os pacientes investigados divididos nos Grupos controle (n=12), DRC estágios 3 e 4 (n=12) e Hemodiálise (n=11) receberam dose única p.o. de 10 mg de nebivolol racêmico. As amostras seriadas de sangue foram coletadas até 48h após a administração do fármaco. Em cada tempo de colheita de sangue, a frequência cardíaca foi avaliada na situação de exercício isométrico durante 2 min com o handgrip, a 30% da contratilidade voluntária máxima. Todos os pacientes foram fenotipados como metabolizadores rápidos do metoprolol, exceto um paciente do Grupo controle fenotipado como metabolizador lento. Os isômeros do nebivolol foram analisados em plasma como concentração total empregando LC-MS/MS e coluna de fase quiral. O método foi linear no intervalo de concentrações de 25-2500 pg de cada isômero do nebivolol/mL de plasma. Os parâmetros farmacocinéticos foram calculados empregando o programa WinNonlin. O teste de Wilcoxon foi empregado para avaliar as razões isoméricas diferentes da unidade (p<0,05) e o teste de Kruskal-Wallis foi empregado para comparar os parâmetros farmacocinéticos entre os três Grupos investigados. A disposição cinética do nebivolol nos pacientes do Grupo controle é enantiosseletiva com acúmulo plasmático (Cmax 1,32 vs 0,88 ng/mL e AUC0-¥ 8,02 vs 4,25 ng.h/mL), menores valores de clearance oral aparente (623,58 vs 1176,40 L/h) e menores valores de volume aparente de distribuição (5383,30 e 6397,70 L) para o isômero lnebivolol. Os parâmetros farmacocinéticos do l-nebivolol e d-nebivolol para os pacientes do Grupo DRC (n=12) permitem inferir, à semelhança do Grupo controle, maiores valores de Cmax e AUC (Cmax 2,40 vs 1,67 ng/mL e AUC0- 10,20 vs 8,37 ng.h/mL) e menores valores de clearance oral aparente (491,51 vs 604,58 L/h) e de volume aparente de distribuição (3527,00 e 5232,50 L) para o isômero l-nebivolol. Semelhante aos Grupos controle e DRC, o Grupo Hemodiálise também apresenta enantiosseletividade com acúmulo acúmulo plasmático (Cmax 1,35 vs 0,78 ng/mL e AUC0- 6,74 vs 4,50 ng.h/mL), menores valores de clearance oral aparente (742,26 vs 1112,10 L/h) e menores valores de volume aparente de distribuição (5704,70 vs 9477,10 L) para o isômero l-nebivolol. A farmacocinética dos isômeros do nebivolol no paciente investigado do Grupo controle, fenotipado como metabolizador lento, difere dos dados apresentados para os pacientes do Grupo controle (n=11), Grupo DRC (n=12) e Grupo Hemodiálise (n=11), fenotipados como metabolizadores rápidos, com observação de razão isomérica de AUC l/d de 4,77 e redução nos valores de clearance oral aparente de ambos os isômeros do nebivolol (67,24 vs 122,07 L/h, respectivamente para os isômeros l-nebivolol e d-nebivolol). Concluindo, a DRC estágios 3 e 4 e a Hemodiálise não alteram a farmacocinética de ambos os isômeros do nebivolol, o volume aparente de distribuição de ambos os isômeros do nebivolol não mostra correlação com o peso dos pacientes, assim como os valores de clearance aparente de ambos os isômeros não mostram correlação com o peso ou com os valores de clearance da creatinina dos pacientes investigados. No entanto, os valores de clearance aparente de ambos os isômeros do nebivolol mostram correlação significativa com a atividade do CYP2D6 avaliada através da RMplasma ix metoprolol/-hidroximetoprolol. A análise PK-PD foi realizada incluindo os 34 pacientes fenotipados como metabolizadores extensivos. O modelo Emax inibitório descreveu a análise PK-PD empregando a variação da frequência cardíaca como parâmetro farmacodinâmico em função das concentrações plasmáticas do d-nebivolol, resultando em valores de Emax de 15,42 bpm e de EC50 de 2,26 ng/mL, seguindo a administração de dose única oral de 10 mg de nebivolol racêmico. / Chronic kidney disease (CKD) is related to inhibition of enzyme systems and drug transporters. Nebivolol, a third generation -blocker, is a selective 1-adrenoceptor antagonist and has vasodilatory properties. It undergoes aromatic hydroxylation through the CYP2D6, alicyclic hydroxylation and glucuronidation. The study evaluates the influence of CKD stages 3 and 4 and hemodialysis on the pharmacodynamics and pharmacokinetics of nebivolol isomers. The investigated patients were divided into 3 groups: control group (n = 12), CKD stages 3 and 4 (n = 12) and hemodialysis (n = 11). They received a single oral dose of 10 mg of racemic nebivolol and serial blood samples were collected up to 48h. At each time of blood sampling, heart rate was assessed in the situation of isometric exercise during 2 min with handgrip at 30% of maximal voluntary contractility. All patients were phenotyped as extensive metabolizers (EM) of metoprolol, except one patient in the control group phenotyped as poor metabolizer (PM). The isomers of nebivolol were analyzed in plasma samples by LC-MS/MS using a chiral phase column. The method was linear over the concentration range of 25-2500 pg of each isomer of nebivolol/mL of plasma. Pharmacokinetic parameters were calculated using the WinNonlin program. The Wilcoxon test was used to assess isomeric ratios different from unit (p <0.05) and the Kruskal-Wallis test was used to compare the pharmacokinetic parameters among the 3 groups investigated. The kinetic disposition of nebivolol was stereoselective in control group with plasma accumulation (Cmax 1.32 vs 0.88 ng/mL and AUC0 0- 8.02 vs 4.25 ng.h/mL), lower values of apparent clearance (623.58 vs 1176.40 L/h) and apparent volume of distribution (5383.30 and 6397.70 L) for the l-nebivolol isomer. The kinetic disposition of nebivolol was also stereoselective in CKD group (n=12) showing higher Cmax and AUC (Cmax 2.40 vs 1.67 ng/mL and AUC0- 10.20 vs 8.37 ng.h/mL) and lower values of apparent clearance (491.51 vs 604.08 L/h) and apparent volume of distribution (3527.00 vs 5232.50 L) for the l-nebivolol isomer. Similarly to CKD and control groups, the Hemodialysis Group showed stereoselectivity with plasma accumulation (Cmax 1.35 vs 0.78 ng/mL and AUC0- 6.74 vs 4.50 ng.h/mL), lower values of apparent clearance (742.26 vs 1112.10 L/h) and apparent volume of distribution (5704.70 vs 9477.10 L) for the l-nebivolol isomer. The pharmacokinetics of nebivolol isomers in the patient phenotyped as PM differed from the data presented to the patients phenotyped as EM, with observation of isomeric ratios AUC l/d of 4.77 and reduced values of apparent clearance of both nebivolol isomers (67.24 vs 122.07 L/h, respectively for l- and d-nebivolol). Concluding, CKD stages 3 and 4 and Hemodialysis did not alter the pharmacokinetics of both nebivolol isomers (Kruskal-Wallis test, p> 0.05), the apparent volume of distribution of both nebivolol isomers showed no correlation with the weight of the patients, the apparent clearance of both isomers also showed no correlation with the weight or with the creatinine clearance of the investigated patients. However, the values for apparent clearance for both nebivolol isomers showed a significant correlation with the CYP2D6 activity evaluated by the metabolic ratios plasma metoprolol/-hidroximetoprolol. PK-PD analysis was evaluated including all the investigated patients phenotyped as EM (n=34). The inhibitory Emax model described the PK-PD analysis using heart rate variation as a pharmacodynamic parameter plotted against the plasma concentrations of the isomer dxi nebivolol, showing Emax values of 15.42 bpm and EC50 of 2.26 ng/mL, following administration of a single oral dose of 10 mg of racemic nebivolol.
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Biomarcadores para diagnóstico precoce de injúria renal em uropatias obstrutivas congênitas / Biomarkers for early detection of renal injury in congenital obstructive uropathies

Kostic, Dusan 19 June 2018 (has links)
Introdução: Os estudos com proteômica especificamente relacionada à nefrologia e urologia pediátrica são limitados. O diagnóstico do comprometimento da função renal e da sua deterioração na presença de uropatias obstrutivas congênitas (UOC) representa o desafio na rotina da nefro-urologia pediátrica. Novos biomarcadores com o potencial para detecção precoce da lesão renal surgiram recentemente, permitindo a escolha da melhor opção terapêutica no tempo hábil, e assim minimizando ou prevenindo o dano renal definitivo. Objetivos: Avaliar o perfil de dois biomarcadores renais séricos: creatinina (CrS) e cistatina C (CyCs); e seis biomaracadores renais urinários: lipocalina associada à gelatinase neutrofílica (NGAL), proteína ligadora de retinol (RBP), molécula de injúria renal 1 (KIM-1), cistatina C na urina (CyCu), fator transformador de crescimento-beta 1 (TGF-beta1) e microalbuminúria (uALB) durante o primeiro ano de vida em lactentes saudáveis; em relação à detecção precoce da lesão renal em lactentes com UOC; em relação à sua capacidade de prever a necessidade de intervenção cirúrgica em lactentes com UOC. Metodologia: 37 lactentes com UOC foram divididos em três subgrupos: 14/37 casos com hidroureteronefrose unilateral (HU), 13/37 com hidroureteronefrose bilateral (HB) e 10/37 com obstrução de vias urinárias baixas (OTUB); e comparados com 24 lactentes saudáveis. No grupo dos pacientes, as amostras de sangue e urina foram obtidas ao nascer e entre o 3º e 7º dia, 1º, 2º, 3º, 6º, 9º e 12º mês de vida. Grupo de controle seguia o mesmo cronograma, com exceção da coleta de sangue que ocorria ao nascer, entre o 3º e 7º dia, no 6º e 12º mês de vida. Todas as amostras foram armazenadas sob - 70 ºC, e analisadas posteriormente através de imunoensaio enzimático quantitativo (ELISA). Resultados: No grupo-controle, CrS, CyCs, CyCu e RBP refletiram a maturação glomerular e tubular. O ritmo de filtração glomerular pela CyCs atingiu os níveis estáveis no 6º mês de vida (93 ± 22 mL/min/1,73 m2). KIM-1 e TGF-beta1 mantiveram os níveis absolutos próximos ao limite de detecção pelo método. Os valores do NGAL no sexo feminino foram significativamente maiores (p=0,005) ao longo do 1º ano, quando comparados aos do sexo masculino. Em comparação aos controles, a coorte dos pacientes apresentou valores mais elevados para todos os biomarcadores urinários no 1º mês de vida (p <= 0,009), sendo que NGAL (p=0,005), TGF-betsa1 (p < 0,001) e ?ALB (p < 0,001) mostraram-se elevados desde o nascimento, em comparação aos controles. O RBP apresentou o melhor desempenho no subgrupo com HB e OTUB (AUC=0,844, sensibilidade >=83,3%, especificidade 94,3%), assim como o KIM-1 no HU (AUC=0,768, sensibilidade 70,7%, especificidade 82,7%). RBP em combinação com TGF-ß1 ou KIM- 1 e NGAL com CyCs e CyCu, atingiram os melhores resultados para detecção da lesão renal (AUC=0,934, sensibilidade 89,4%, especificidade 92,8%; AUC=0,896, sensibilidade 86,8%, especificidade 81,1%; AUC=0,867, sensibilidade 92,4%, especificidade 79,5%, respectivamente). Nos pacientes operados, os níveis elevados de RBP (p <= 0,043), NGAL (p <= 0,043), KIM-1 (p <= 0,03) e TGF-beta1 (p <= 0,034) baixaram significativamente após a cirurgia, no subgrupo com HU e OTUB. NGAL, isolado ou em combinação, com CyCs e CyCu demonstrou o melhor desempenho para determinar a necessidade cirúrgica (AUC=0,801, sensibilidade 63,6%, especificidade 96,7%; AUC=0,881, sensibilidade 87,7%, especificidade 82,2%, respectivamente). A analise do perfil dos biomarcadores indicou a necessidade da intervenção cirúrgica em 55,4% (7/13) dos casos não-operados e antecipou a decisão cirúrgica no mínimo 3 meses, em 58% (14/24) de todos os pacientes operados, baseada nas diretrizes atuais. Conclusão: A evolução dos valores normais dos biomarcadores no primeiro ano de vida, pode servir como a base para os próximos estudos de detecção precoce de afecções uro-nefrologicas. RBP, NGAL, KIM-1, TGF-beta1 e CyC, individualmente ou em combinação, demonstraram um forte potencial para identificar a lesão renal e servir como uma ferramenta de diagnóstico não-invasivo para diferenciar pacientes que necessitam de intervenção cirúrgica precoce daqueles que se beneficiariam de uma conduta conservadora / Introduction: The proteomics studies specifically related to pediatric nephrology and urology are limited. The diagnosis of renal function impairment and deterioration in congenital obstructive uropathies (COU) represents challenge in pediatric nephrourology routine. New renal biomarkers applied in this setting have potential for early renal injury detection, allowing reliable choice of optimal therapeutic options and thus preventing or minimizing definitive renal damage. Objectives: To analyze the first-year profiles of two serum renal biomarkers: Creatinine (CrS) and Cystatin C (CyCs); and six urinary renal biomarkers: Neutrophil Gelatinase-Associated Lipocalin (NGAL), Retinol- Binding Protein (RBP), Kidney Injury Molecule-1 (KIM-1), urine Cystatin C (CyCu), Transforming Growth Factor Beta 1 (TGF-beta1), and microalbuminuria (uALB) in a cohort of healthy infants; in relation to early detection of renal injury capability in a group of infants with COU; in relation to capability of predicting the need for surgery in a group of infants with COU. Methods: 37 infants with COU were divided in 3 subgroups: 14/37 cases with unilateral hydro(uretero)nephrosis (UH), 13/37 with bilateral hydro(uretero)nephrosis (BH) and 10/37 patients with lower urinary tract obstruction (LUTO), compared with 24 healthy infants matched by gestational age and birth weight. In the patient group, blood and urine samples were collected at birth, between 3rd-7th day, at 1st, 2nd, 3rd, 6th, 9th and 12th month of age. In the control group urine sampling followed the same routine with exception that blood sampling was obtained between 3rd-7th day, at 6th and 12th month of age. The samples were stored at -70 ºC, and thereafter analyzed by quantitative enzymatic immunoassay (ELISA). Results: In the group of healthy controls, the values of CrS, CyCs, CyCu and RBP reflected glomerular and tubular maturation. The glomerular filtration rate by CyCs reached steady-state levels at 6th month of life (93 ± 22 mL/min/1,73 m2). KIM-1 and TGF-beta1maintained very low absolute levels, near to the limit of detection by the method. NGAL levels in females were significantly higher (p=0,005) throughout the first year of life, when compared to male gender. In the cohort of patients, all the urinary biomarkers showed significantly higher values at the first month of life (p <= 0,009), while NGAL (p=0,005), TGF-beta1(p < 0,001) e uALB (p < 0,001) were high since birth, compared to control group. The best single biomarker performance was achieved by RBP in BH and LUTO subgroups (AUC=0,844, sensitivity >= 83,3%, specificity 94,3%), and by KIM-1 in UH subgroup (AUC=0,768, sensitivity 70,7%, specificity 82,7%). The best biomarker combination results for all subgroups were obtained by matching RBP with TGF-beta1 or KIM-1 and NGAL with CyC (AUC=0,934, sensitivity 89,4%, specificity 92,8%; AUC=0,896, sensitivity 86,8%, specificity 81,1%; AUC=0,867, sensitivity 92,4%, specificity 79,5%, respectively). In the operated group of patients, the levels of RBP (p <= 0,043), NGAL (p <= 0,043), KIM-1 (p <= 0,03) e TGF-beta1 (p <= 0,034) dropped significantly after surgery, in UH and LUTO subgroups. NGAL alone or in combination with CyCs and CyCu, demonstrated the best performance to determine the need for surgery (AUC=0,801, sensitivity 63,6%, specificity 96,7%; AUC=0,881, sensitivity 87,7%, specificity 82,2%, respectively). Biomarkers\' profile analysis indicated the need for surgical intervention in 55,4% (7/13) of non-operated cases and anticipated clinically based surgical decision for at least 3 months, in 58% (14/24) of all operated patients. Conclusions: The presented biomarkers\' normal values evolution during the first year of life can be of use as a base for future studies that will involve early detection of uronephrological disorders in infants. RBP, NGAL, KIM-1, TGF-beta1 and CyC, alone or in combination, demonstrated strong capability to identify renal injury and serve as a noninvasive diagnostic tool for differentiating between infants that require early surgical intervention from those who would benefit from conservative approach
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Estudo da ocorrência da doença renal crônica em gatos naturalmente infectados pelo vírus da imunodeficiência felina / Occurrence of chronic kidney disease in cats naturally infected with feline immunodeficiency virus

Avila, Andreza 30 June 2009 (has links)
Gatos infectados naturalmente pelo vírus da imunodeficiência felina (FIV) desenvolvem uma síndrome semelhante à causada pela infecção pelo vírus da imunodeficiência humana (HIV), sendo a espécie felina um modelo promissor de estudo da infecção pelo HIV. Em humanos a nefropatia associada à infecção pelo HIV é uma causa comum e preocupante de complicação por resultar em insuficiência renal progressiva nos pacientes acometidos. Achados clínico-patológicos identificados em gatos naturalmente infectados pelo FIV também sugerem um envolvimento renal. Com o intuito de determinar a ocorrência de doença renal crônica (DRC) em gatos infectados pelo FIV e uma possível associação entre essas doenças, foi estudada uma população de 44 gatos, sendo 20 animais naturalmente infectados e 24 animais não-infectados, submetidos às mesmas condições higiênico-sanitárias, de dieta e quanto à exposição a agentes infecciosos. Os animais foram acompanhados durante um período de 18 meses, durante o qual foram realizadas dosagens periódicas de creatinina sérica e mensuração da relação proteína:creatinina urinária (RPC-U). A ocorrência de DRC em gatos infectados pelo FIV foi de 45%, maior em comparação aos 25% referentes ao grupo não-infectado, embora não tenha havido diferença estatisticamente significativa entre esses grupos. A proteinúria em pelo menos um momento foi observada em 60% dos gatos infectados pelo FIV e em 26,1% dos gatos não infectados (p= 0,037). Considerando proteinúria persistente como aquela observada em pelo menos 3 momentos consecutivos, os gatos infectados tiveram ocorrência de 30,8% em comparação a 6,7% referente ao grupo não infectado (p> 0,05). Houve associação entre o óbito e a DRC apenas nos gatos infectados (p= 0,02). Concluiu-se que, apesar de a ocorrência de doença renal crônica e de proteinúria não ter sido estatisticamente maior diante da infecção pelo FIV, a associação entre o óbito e a DRC nos animais infectados sugere que o FIV pode contribuir para o agravamento da DRC, levando a rápida deterioração do organismo e considerável diminuição da sobrevida. / Cats naturally infected with the feline immunodeficiency virus (FIV) develop a syndrome that share common characteristics with the human immunodeficiency virus (HIV) infection. For this reason, felines are considered a promising model for the study of HIV infection. HIV associated nephropathy is a common and concerning complication in human beings, resulting in progressive renal insufficiency. Likewise clinico-pathological findings in naturally infected cats suggest a renal involvement. To evaluate the occurrence of chronic kidney disease (CKD) in cats infected with FIV and to verify a possible association between both diseases, a population of 44 cats submitted to the same sanitary handling, diet and exposure to infectious agents was studied. Of these cats, 20 were naturally infected with FIV and 24 were free of FIV infection. Animals were periodically accompanied for a 18-month period through serum creatinine and urinary protein:creatinine ratio measures. The occurrence of CKD in cats infected with FIV was 45%, a value higher than the observed in non-infected cats (25%), but no statistical difference was found. Proteinuria in at least one moment of evaluation was observed in 60% of infected cats and in 26,1% of non-infected cats (p=0,037). Considering the criterion of persistent proteinuria as the observation of urinary protein excretion in at least 3 consecutive moments, infected cats exhibited occurrence of 30,8% compared with 6,7% in the non-infected group (p>0,05). It was observed an association between death and CKD only in the cats infected with FIV (p=0,02). In conclusion, despite occurrence of CKD and proteinuria have not been statistically higher in infected cats than in non-infected one, the association between death and CKD in FIV-infected cats suggests FIV may contribute for the worsening of CKD, resulting in a quicker organic dysfunction and marked reduction of survival.

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