Dissertations / Theses on the topic 'Kidneys – Diseases'

Background and objectives Chronic kidney disease (CKD) refers to a progressive and irreversible loss of kidney function, the key outcomes of which are end-stage kidney disease (ESKD), requiring dialysis or a kidney transplant, or premature death typically due to cardiovascular complications. CKD is identified either by evidence of kidney damage (especially proteinuria or albuminuria) or decreased kidney function, measured according to glomerular filtration rate (GFR). Prevention of CKD, and timely intervention where disease does occur, is an emerging public health priority. However, our understanding of the epidemiology of CKD is still limited, and the evidence base concerning potentially modifiable lifestyle-related risk factors is often deficient or contradictory. Awareness of CKD in the community is low, and informed public health approaches to the burden of disease rare. This thesis is presented as a collection of published works which explore the epidemiology of lifestyle-related and social risk factors for CKD in the general population, and consider potential strategic approaches to the burden of CKD in Australia and internationally. The majority of the analyses presented are based on data derived from the Australian Diabetes, Obesity and Lifestyle (AusDiab) study, a prospective national survey of diabetes, cardiovascular and kidney disease in Australians aged 25 years or older which completed 5-year follow—up in 2005.

The proximal tubule of the renal cortical nephron is highly susceptible to intoxication by chemical agents. An in vitro system was developed to study directly the effects of nephrotoxic chemicals on this renal sub-organ fraction without the complication of extrarenal factors. Segments of proximal tubules were isolated by a mechanical method from the kidneys of young rabbits. Tubules obtained by this method retained biochemical, functional, and morphological features comparable to those existing in vivo. Preliminary acute susceptibility studies demonstrated that the isolated proximal tubule segments were sensitive to a variety of known nephrotoxic agents that target the proximal tubule. These agents include halogenated hydrocarbons, heavy metals, and a halogenated vinyl cysteine conjugate. Incubation conditions were optimized to maintain the viability of proximal tubule suspensions for up to four hours. Longer incubation times made it possible to establish a chronology of early tubule responses to chemical intoxication. Long term incubation of proximal tubule suspensions with two model nephrotoxins, cadmium chloride and S-(trans-1,2-dichlorovinyl)-L-cysteine, produced in vitro tubule response patterns similar to those reported in vivo for these agents. While not entirely representative of in vivo exposure conditions, suspensions of isolated proximal tubules are an easily obtained system that proved equally applicable as a screening technique for nephrotoxic compounds or as an in vitro system for delineating proximal tubule response to chemical insult.

Factors Influencing Women's Adaptation to Hemodialysis When Renal Transplantation is not an Option The intent of this study was to explore and describe factors that influence adaptation from the perspective of women on hemodialysis for whom renal transplantation is not an option. Phenomenology was the research design selected for this study in order to understand the experience of these women clients. Data were collected during audio-taped interviews of eight women and were analyzed concurrently with data collection to identify common themes. Two central themes emerged: the adaptation process and the theme of connectedness. The adaptation process was described as a six-phase process. Connectedness was defined as being connected to others and/or sources of life's energy. Several key factors that either facilitated or interfered with adaptation were identified for each of these two themes. Key factors that facilitated adaptation throughout the adaptation process Included a first run on dialysis, experience with adversity, emotional and instrumental support, coping behaviors such as asserting control and reframing the situation, diversions, adequate rest and confidence in health-care professionals. Factors interfering with adaptation to hemodialysis throughout the adaptation process included the gradual and ambiguous nature of renal disease, increasing dependence, reduced energy, transportation to dialysis, compromised somatic health, difficulty with assertiveness, prolonged stressors and lack of confidence in health-care professionals. Specific factors that influenced connectedness were identified. The facilitating factors identified were satisfactory relationships, nurturing others, normalizing, a harmonious atmosphere on the hemodialysis unit and pleasurable activities. Key factors interfering with adaptation related to the connectedness theme were isolation from others, unsympathetic others, ineffective communication with health-care professionals, and exclusion from activities. The findings relative to the adaptation process were discussed in the light of the literature on adapting to illness and stress. Connectedness was discussed primarily in relation to the literature exploring the socialization of women. Implications for nursing practice, education and research arising from these findings were outlined.
Applied Science, Faculty of
Nursing, School of
Graduate

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Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

Nephrology nursing requires a specific set of clinical skills and knowledge. When a professional nurse with no previous dialysis experience enters the field of nephrology nursing he or she has no nephrology related paradigms from past experiences to use as a point of reference. As a result of the rapid growth of the private dialysis company experienced over the past 10 years, many management and support service positions became available. Internal promotions resulted in the movement of experienced professional nurses from the clinical field into management and support services positions, resulting in a sudden loss of skilled individuals from the clinical field. To mitigate this effect, a training intervention was started. The newly appointed managers were all required to work in the clinical field for sixteen hours per month to expose the less experienced professional nurses to the more experienced professional nurses in order to assist them with skill acquisition thus enabling the advanced beginner and competent nurse to become a proficient nurse and/or an expert in the field of nephrology nursing. Experiential learning is not a spontaneous process but depends on many factors that could either hinder or facilitate skill acquisition. This study aimed to explore and describe the aspects that facilitate or hinder skill acquisition during the training intervention that was implemented in private chronic haemodialysis units and to write guidelines to optimize skill acquisition during the training intervention. The study followed a quantitative, descriptive, exploratory, contextual, survey design. Data was collected using a tool based on the theory of nursing accompaniment by Kotze, Kolbs theory on experiential nursing, a framework of strategies that facilitate skill acquisition by King and a generalized tool, the Learning Transfer Skills Inventory (LTSI) that was developed by Holton and Bates to measure learning transfer and factors that contribute and hinder training interventions. Data was analysed with the support of a statistician. The findings were reported and discussed in relation to the current literature. Measures were put in place to ensure validity and reliability, and ethical principles were adhered to throughout the study. Guidelines to optimize skill acquisition were developed. The limitations of the study were the sample size and the response rate. There was a paucity in existing research regarding skill acquisition in Nephrology nursing and limited statistical variance amongst the aspects that facilitate or hinder skill acquisition. It is recommended that the guidelines be implemented to measure the impact they have in the organization.

The effects of the biological cross-linker transglutaminase, the neutrophil oxidant hydrogen peroxide, and neutrophil proteinases on glomerular basement membrane permeability have been examined using an in vitro model of glomerular ultrafiltration. The main focus of the study lies in determining whether any of the test agents were able to render glomerular basement membrane more permeable to protein. Guinea pig liver transglutaminase was used as a model enzyme to test for the effect of biological cross-linkers on glomerular basement membrane permeability. It cross-linked glomerular basement membrane proteins, caused membrane contraction, and rendered glomerular basement membrane less permeable both to water and the low molecular weight protein marker myoglobin but had no effect on the membrane permeability to the high molecular weight marker protein bovine serum albumin or serum protein. The pathophysiological relevance of the effect is discussed. Hydrogen peroxide increased glomerular basement membrane permeability to water and proteins but the effect depended on hydrogen peroxide concentration and incubation time. The minimum concentration needed to render glomerular basement membrane more permeable to bovine serum albumin and serum protein was 1 M and the minimum incubation time needed was 6 hrs. A respiratory burst analysis of activated neutrophils showed that the average concentration of hydrogen peroxide that could be generated by the neutrophils was less than 50 mM and the time taken for extracellular hydrogen peroxide concentration to fall off to zero was less than 1 hr. Therefore, neutrophils seemed unable to generate and sustain a sufficiently high hydrogen peroxide concentration to render glomerular basement membrane more permeable to protein in vivo. Proteinases extracted from pig neutrophil granules were used to assess their effect on glomerular basement membrane permeability. The extract showed activity against glomerular basement membrane and the activity was primarily attributed to the serine proteinases elastase and cathepsin G, judged from substrate and inhibitor analyses. The proteinase extract also contain latent metalloproteinases, activatable by the organomercurial 4-aminophenyl mercuric acetate and calcium ions. Once activated, they also showed activity against glomerular basement membrane. The extract rendered glomerular basement membrane more permeable to water, myoglobin, bovine serum albumin, and serum protein. The increase in membrane permeability to water and proteins was due to membrane thinning and an increase in the intrinsic porosity of the membrane. When the serine and metalloproteinases were allowed to act in concert, they synergistically degraded glomerular basement membrane and increased the membrane permeability to serum protein and water. The study provides the first direct evidence that pathophysiological amounts of serine and metalloproteinases are able to render glomerular basement membrane more permeable to protein and suggests they may be capable of promoting proteinuria in neutrophil-dependent forms of immune glomerulonephritis.

Data from dialysis units in the Northern Territory and, from a rural community screening program in South Australia, suggested there was a high prevalence of renal disease in Aboriginal Australians. This thesis documents the high prevalence of urinary abnormalities in three Aboriginal communities in the Northern Territory and examines factors of aetiological relevance. After ethical approval from the local institutional ethics committee which has Aboriginal representation, a randomly chosen group of 327 adults and 180 children consented to participate in pilot studies in three communities. Subsequently a family-based study of 16 families comprising all 219 persons over the age of 10 years was undertaken in the community with the highest prevalence of renal disease. Subjects with renal disease were identified on the basis of a urinary protein to creatinine ratio of > 50 mg/mmol; this measure was shown to be reproducible; urine was also examined by microscopy and culture. Anthropometric and blood pressure measurements were made under standard conditions. Biochemical parameters were assayed on a sample of blood collected 2 hours after a 75g glucose load (in adults) or at the time of collection of throat and skin swabs for streptococcal surveillance (in children). In the community with the highest frequency of renal disease, some of the renal disease was not associated with diabetes, but was familial and associated with glomerular haematuria; in this same community glomerular haematuria and significant proteinuria were seen also in children. In all three communities, renal disease was associated with obesity, diabetes mellitus and hypertension. In none of the communities was renal disease associated with HBsAG, or evidence of hepatic disease. Although urinary tract infection was detected in some subjects with diabetes, it was not frequent enough to account for the high prevalence of renal disease in diabetics, nor for the high prevalence of renal disease in the Aboriginal communities studied.

Surgical resection is the best option for both liver and kidney cancers, which providing the long term survival. However intraoperative blood loss can be a significant challenge, and is clearly associated with morbidity and mortality. Radiofrequency ablation (RFA) precoagulation has been introduced into liver and kidney surgery. Promising results have already achieved in reduction of intraoperative blood loss. In this thesis, a detailed explanation on precoagulation by RFA has been given. Our group developed a novel bipolar multi-array RFA device ??? InLine (ILRFA). In this thesis, we have investigated the performance in a variety of fields. In the study of ILRFA-assisted laparoscopic liver resection, ILRFA was easily employed through a hand port and achieved significant decrease of blood loss compared to control group (p < 0.05). In the liver trauma study, ILRFA produced a 63.88% reduction of blood loss in peripheral injury and 53.57% in central injury respectively. In postoperative evaluation of ILRFA-assisted liver resection, animals underwent an uneventful recovery, no complications occurred. Histological examination revealed a typical post RFA evolution. In ILRFA-assisted partial nephrectomy, the mean intraoperative blood loss 35 ?? 7 ml in the ILRFA and 152 ?? 94 ml in the control, a 77.0% reduction (P = 0.024). The mean blood loss per centimetre resection area was 2.09 ?? 1.41 ml/cm2 in the ILRFA compared with 12.79 ?? 1.68 ml/cm2 in controls, the reduction was 79.0% (P = 0.019). In ILRFAassisted laparoscopic partial nephrectomy, the mean intraoperative blood loss was 32 ?? 15 ml in the ILRFA and 187 ?? 69 ml in the control group, a 77.0% reduction (P = 0.043). The mean blood loss per centimetre resection area was 2.27 ?? 0.95 ml/cm2 in the ILRFA compared with 26.46 ?? 8.81 ml/cm2 in controls, the reduction was 79.0% (P = 0.047). In the renal trauma experiment, ILRFA also achieved promising results in haemostasis. We believe that ILRFA is a useful device which may help in the treatment of patients with liver and kidney illness.

Objective The goal of this study is to report on the linguistic validation and reliability of the Hong Kong Chinese version of the Pediatric Quality of Life Inventory™ (PedsQL™) End-stage Renal Disease Module for Children with end-stage renal disease (ESRD) in Hong Kong, and its use to assess health-related quality of life (HRQOL) in end-stage renal disease children receiving different treatment modalities: peritoneal dialysis, haemodialysis and renal transplantation. Methods In part 1, forward and backward translations following a stringent validation protocol produced the Chinese translation version. Content validity of the translated instrument was assessed. In part 2, internal consistency and reliability of the questionnaire was evaluated by 38 pairs of parents and children with end-stage renal disease aged 5 to 18. The data was further analysed according to different treatment modalities. Results The translated Hong Kong Chinese version of the Pediatric Quality of Life Inventory ™ (PedsQL™) End-stage Renal Disease Module (PedsQL™ 3.0 ESRD Module-HKC) was found to have good content validity and was acceptable to most patients and parents. Internal consistency was excellent (Cronbach’s α = 0.91 in Patient version and = 0.94 in Parent version). Test-retest reliability, determined with the intraclass correlation coefficients, was excellent (0.89 in Patient version and 0.93 in Parent version). It was found that there was significant better HRQOL in patient received renal transplantation compared with Dialysis (peritoneal dialysis or haemodialysis, p=0.006.) Conclusions This study suggested good content validity, internal consistency, and reliability of the Chinese version of the Pediatric Quality of Life Inventory ™ (PedsQL™) End-stage Renal Disease Module (PedsQL™ 3.0 ESRD Module-HKC). It opened a new dimension of health care assessment for end-stage renal disease children in Hong Kong. Transplantation was reported to have a significant better quality of life score. Further studies with larger samples should be performed to confirm the psychometric properties of this translated instrument.
published_or_final_version
Public Health
Master
Master of Public Health

Despite a better understanding of the pathogenesis and progression of chronic kidney disease (CKD), the functional decline of kidney function in patients with any form of nephropathy remains the greatest challenge to clinicians. Renal fibrosis is considered the ‘point of no return’ for any form of chronic kidney disease, including diabetic nephropathy, and renal dysfunction induced by inflammation, hypoxia, reactive oxygen species, and lipotoxicity. However, there are limited therapeutic options to mitigate against kidney fibrosis, and therefore novel agents are required to add to the armamentarium of therapies for slowing the progression of CKD. In this thesis HK-2 cells were used as an in vitro model to study the cellular response to known mediators of renal injury. HK-2 cells are derived from proximal tubular cells (PTCs) from normal adult human renal cortex. They retain phenotypic and functional characteristics indicative of well-differentiated PTCs. These cells were cultured in conditions inherent in diabetes mellitus (DM) mimicking the microenvironment of CKD. The functional relationship between transforming growth factor-Bl (TGF—Bl), bone morphogenetic protein-7 (BMP-7) and Kriippel-like factor—6 (KLF-6) in epithelial mesenchymal transition (EMT) was studied using recombinant human TGF-B] and BMP- 7. The BMP receptors and markers of EMT were assessed in HK-2 cells after exposure to 0.5 ng/ml of TGF-Bl for 48 hours. Overexpression of BMP-7 was induced and BMP receptor expression was assessed in KLF-6 overexpressing and silenced cells. TGF-Bl significantly down-regulated bone morphogenetic protein receptor-IA (BMPR-IA) expression. Cells overexpressing KLF-6 showed decreased expression of BMPR-IA and other type I BMP receptors, and silencing of KLF-6 increased BMPR—IA expression. Cells overexpressing BMP-7 had significantly higher E-cadherin and phosphorylated Smadl/5/8, which was not observed with concurrent TGF-Bl exposure. In vivo studies confirmed a reduction in BMP-7 and BMPR-IA but an increase in KLF-6 expression in established diabetic nephropathy. TGF-Bl and KLF-6 synergistically induced suppression of BMPRIA and downstream reduction of BMP-7 signalling. These findings suggest that the presence of TGF-Bl in multiple forms of nephropathy mitigates against the use of thMP- 7 as an antifibrotic therapeutic agent.

Cimetidine is a histamine H2-receptor antagonist that is among the most widely prescribed drugs in the world. In addition to its inhibitory action on gastric acid secretion, a possible role in kidney tubulointerstitial disease has been suggested. Isolated reports have also suggested an association between cimetidine administration and acute interstitial nephritis. The present study examined the effect of cimetidine on renal function in the rat. The nine rats used in this study had normal renal function and urinalyses before treatment with cimetidine. The cimetidine treated rats then developed a clinical picture of weakness, hematuria, proteinuria, casturia, oliguria, and increases in serum blood urea nitrogen and creatinine.Following the 6 weeks treatment period, all rats were sacrificed and their kidneys prepared for microscopic study. Histologically, the patchy, intense tubulointerstitial infiltration of lymphocytes, plasma cells, and other cells observed in the cortex of the rat kidneys is quite similar to findings described in human cases of drug-induce hypersensitivity tubulointerstitial disease. In addition, other pathologic conditions which can cause tubulointerstitial disease were adequately ruled out. Specifically, bacterial pyelonephritis was excluded as a result of the consistently sterile urine test. In conclusion, the author feels that the clinical, aboratory, and histologic findings in this study strongly suggests an association between of tubulointerstitial disease and the use of cimetidine.
Department of Physiology and Health Science

Introduction Chronic kidney disease (CKD) is a common and important public health problem, with significant impact on the person’s quality of life and chances of survival. Cardiovascular disease is major cause of morbidity and mortality among people with CKD. Cancer is also a well-recognised complication in people on dialysis and with kidney transplants, but has not been adequately assessed in people with mild to moderately reduced kidney function. It is uncertain whether the basis of such increased risk in the end-stage kidney and transplant populations is solely related to their immunocompromised health states, or there are plausible biological reasons to explain the association beyond current knowledge. Screening, which allows early detection and subsequent treatment, is effective in reducing cancer-related deaths for common cancer such as breast, colorectal and cervical cancers in the general population. Given the inherent differences in the overall cancer risk and life expectancy among people with CKD, it is plausible that the effects, costs, and harms of routine population cancer screening may be different to the general population. This thesis is presented as published work on the theme of cancer and chronic kidney disease. The first chapter summarises the existing epidemiological evidence of association between cancer and kidney transplantation. The second chapter, uses data from the Blue Mountain Eyes Study cohort and linkage with the New South Wales Central Cancer Registry, explores the hypothesis of increased cancer risk in people with mild to moderately reduced kidney function. The work presented in the last five chapters of this thesis have extrapolated, critically appraised, and synthesized the available evidence for cancer screening in the general, end-stage kidney disease and kidney transplant populations.

Regardless of the original cause and etiology, the progression of kidney disease follows a final common pathway associated with tubulointerstitial injury, in which proximal tubular epithelial cells (PTEC) are instrumental. Kidney injury molecule-1 (KIM-1) is an emerging biomarker of kidney tubular damage. It is markedly expressed and released into urine in various animal models and human kidney diseases. This study aimed to explore the underlying mechanism regulating the release of KIM-1 by PTEC. First, expression and release of KIM-1 by primary cultured human PTEC were examined. In quiescent PTEC, KIM-1 was detected at the plasma membrane and in the cytoplasm. A transwell system, in which PTEC were grown as monolayer on permeable membrane, was used to examine the polarized release of KIM-1. PTEC constitutively released KIM-1 from their apical surface, and the release was independent of gene expression or protein synthesis. The KIM-1 release process by PTEC was enhanced dose- and time-dependently by two important kidney injury mediators, human serum albumin (HSA) and tumor necrosis factor (TNF)-α, and was inhibited by the presence of broad-spectrum inhibitors of matrix metalloproteinases (MMP). Second, the potential sheddases responsible for KIM-1 shedding were identified by quantitative polymerase chain reaction (PCR) array system, in which the gene expression of a panel of MMP members was screened. The gene expression of MMP-3, MMP-7 and MMP-9 was up-regulated by PTEC under HSA or TNF-α activation. Blockade experiments with synthetic MMP inhibitors or MMP gene knockdown by small interfering RNA transfection, revealed that the constitutive or accelerated KIM-1 shedding was mediated by MMP-3, but not MMP-7 or MMP-9. The role of MMP-3 in KIM-1 shedding was further defined by additional data showing the enhanced MMP-3 synthesis by HSA- or TNF-α-stimulated PTEC, and the up-regulated KIM-1 shedding by PTEC following exogenous MMP-3 treatment. Third, the regulatory mechanism of MMP-3-mediated KIM-1 shedding was investigated. Treatment of PTEC with HSA or TNF-α up-regulated the reactive oxygen species (ROS) generation, and its kinetics ran parallel to the increase of KIM-1 shedding and MMP-3 synthesis. In addition, exogenous hydrogen peroxide dose-dependently induced KIM-1 shedding and MMP-3 synthesis, which were abolished by the presence of an oxidation inhibitor. These evidence suggest that ROS play an essential role in regulating the MMP-3-mediated KIM-1 shedding by PTEC. Finally, a mouse model of acute kidney injury induced by renal ischemia and reperfusion (I/R) was established to translate the in vitro findings. Reduced kidney function and increased urinary KIM-1 level were observed in mice after renal I/R treatment. Strikingly, the expression of MMP-3 and KIM-1 in the I/R treated mice was most profound in the S3 segments of the proximal tubules, where is the most susceptible area to oxidative stress. Taken together, these in vivo data have further strengthened the distinct roles of ROS and MMP-3 in KIM-1 shedding during PTEC injury. In conclusion, ROS generated by the injured PTEC activate MMP-3, which release the soluble KIM-1 through the ectodomain shedding process.
published_or_final_version
Medicine
Master
Master of Philosophy

Idiopathic Membranous nephropathy (MN) is a common cause of nephrotic syndrome in humans, and many patients progress to end-stage kidney disease. The best available animal model of MN is active Heymann nephritis (HN) in which rats are immunized with renal tubular antigen (RTA) in complete Freund's adjuvant (CFA). Rats develop heavy proteinuria, a key measure of glomerular damage, and the disease is histologically identical to human MN. It has been thought that HN is mediated by antibody-based mechanisms. More recent evidence demonstrates a critical role for cytotoxic T cells. This thesis aims to further examine the role of T cell responses in active HN. First, the effect of the anti-CD3 monocIonal antibody (mAb) G4.18 was investigated. Anti-CD3 given 4 weeks after immunization prevented the development of proteinuria, delayed anti-RTA antibody responses, and reduced glomerular infiltration of CD8+ T cells and macrophages, but did not affect glomerular deposition of IgG or complement. Increased mRNA expression of the Th2 cytokines IL-4 and IL-5 was detected in draining lymph nodes. These findings suggest that immune deviation to a Th2 response reduces glomerular injury in HN. Second, the role of CD4+ T cells in immune tolerance was examined. Rats were given RTA in incomplete Freund's adjnvant (lFA) to induce tolerance to RTA, and three weeks later were immunized with RTA in CFA. Anti-CD4 mAb therapy at the time of RTA1IFA treatment had no effect on subsequent proteinuria or anti-RTA autibodies. Third, the role of IL-4 in this model of immune tolerance was examined. Anti-IL-4 mAb therapy blocked the induction of tolerance, and led to the development of proteinuria. Finally, the effect of treatment with IL-4 and IL-5 was examined. Treatment with these cytokines separately or together after immunization blocked the development of proteinuria, without a consistent effect on anti-RTA antibodies. These results demonstrate a central role for T cell regulation in HN, and show that immune deviation to a Th2 response is protective against glomerular injury. The findings may have implications in the future for focused therapeutic intervention in human idiopathic MN.

Proteinuria has been recognized as a common feature in many forms of chronic kidney disease (CKD). As traditional medications for proteinuric nephropathy, such as blockade of the renin-angiotensin system (RAS), has only achieved limited clinical success, more effective renoprotective strategies need to be explored. Bone marrow-derived mesenchymal stem/stromal cells (BM-MSCs) have recently shown promise as a therapeutic tool in acute kidney injury (AKI) models. The therapeutic potential of bone marrow-derived mesenchymal stem cells (BM-MSCs) in proteinuric nephropathy models is unknown. Using a co-culture model of human proximal tubular epithelial cells (PTECs) and BM-MSCs, I first examined the potential effect of BM-MSCs in albumin-induced pro-inflammatory response and epithelial-to-mesenchymal transition (EMT) in PTECs. The unstimulated BM-MSCs exerted moderate suppressive effect on tubular inflammation as only albumin-induced CCL-2 and CCL-5 expression was attenuated in PTECs. When concomitantly stimulated by albumin excess, however, BM-MSCs remarkably suppressed albumin-induced tubular IL-6, IL-8, TNF-α, CCL-2, and CCL-5 expression, suggesting albumin overloaded milieu to be a prerequisite for them to fully exhibit their anti-inflammatory effects. This effect was mediated via deactivation of tubular NF-κB signaling as BM-MSCs prevented the overexpression of p-IκB and nuclear translocation of NF-κB. In addition, albumin-induced tubular EMT, as shown by the loss of E-cadherin and induction of α-SMA, FN-1 and collagen IV in PTECs, was also prevented by BM-MSC co-culture. To dissect the mechanism of action, I next explored the paracrine factors secreted by BM-MSCs under an albumin-overloaded condition and studied their contribution to the protective effect on tubular inflammation and EMT. Albumin-overloaded BM-MSCs per se overexpressed 34 paracrine factors, of which hepatocyte growth factor (HGF) and TNFα-stimulating gene (TSG)-6 were regulated by P38 and NF-κB signaling. These paracrine factors suppressed both the proinflammatory and profibrotic phenotypes in albumin-induced PTECs. Neutralizing HGF and TSG-6 abolished the anti-inflammatory and anti-EMT effects of BM-MSC co-culture in albumin-induced PTECs, respectively. Finally, in albumin-overloaded mice, a well established murine model reminiscent of human CKD, treatment with mouse BM-MSCs markedly reduced BUN, tubular CCL-2 and CCL-5 expression, interstitial macrophage, α-SMA and collagen IV accumulation independent of changes in proteinuria, together with upregulated renal cortical expression of HGF. Exogenous BM-MSCs were detected in their kidneys by PKH-26 staining. Collectively, these in vitro and in vivo data suggest a modulatory effect of BM-MSCs on albumin-induced tubular inflammation and fibrosis and underscore a therapeutic potential of BM-MSCs for CKD in the future.
published_or_final_version
Medicine
Doctoral
Doctor of Philosophy

Patients were selected for the study on the basis of 1: A diagnosis of systemic Lupus Erythematosus according to the 1982 revised American Rheumatology Association criteria47 and 2: An adequate biopsy defined as containing at least six glomeruli. Patients were biopsied at Groote Schuur Hospital during the period 1978 to 1988 and the indications for renal biopsy were clinical based on laboratory results of renal function. Patients were followed between 1 and 120 months with a mean observation period of 34 months. The clinical records were scrutinised and the following pa·rameters were noted at the time of biopsy: age, sex, race, time from diagnosis to biopsy, serum urea, creatinine, creatinine clearence and urinary 24 hour protein. Using the latest serum urea, creatinine, creatinine clearence and / or 24 hour urinary protein where available, outcome was graded as: 1: An improvement in renal function 2: A stable renal function 3: Deterioration in renal function 4: Patient on dialysis 5: Death due to disease

Publications 1-49 represent studies that I have undertaken myself or conjointly over a 34 year period to investigate a variety of issues relating to diseases of the kidney and urinary tract in children. The studies were carried out at the Royal Alexandra Hospital for Children, Camperdown when I was Clinical Superintendent from 1968 - 1970; The Department of Paediatrics, University of Minnesota, Minneapolis, USA when I was Overseas Research Fellow of the Post Graduate Foundation in Medicine, University of Sydney, 1970 - 1972, then as Staff Physician in Nephrology at the Royal Alexandra Hospital for Children, Camperdown, 1972 - 1977, and then Head of that Department at the Hospital until 1995 and then as an Honorary Staff Specialist at that hospital. Some of the studies were done conjointly with members of the Renal Unit of Royal Prince Alfred Hospital where I hold an Honorary appointment and others conjointly with members of the Renal Unit of Prince Henry Hospital, Little Bay. I was appointed Clinical Associate Professor to the Department of Paediatrics and Child Health, University of Sydney in 1993. In 1966 paediatric nephrology was in the early phase of development as a medical subspecialty. There was no definitive textbook, the first was published in 1975 (Pediatric Nephrology, Ed. Mitchell I. Rubin. Williams and Wilkins.). In the preface to the 2nd edition of Renal Disease (Blackwell) in 1967 the editor D.A.K. Black noted that he had included a chapter on paediatric aspects which had been planned for the 1st edition in 1962 but ”it could not be arranged”. In the chapter on Renal Disease in Children the author, D.Macauly, comments that the mortality rate of acute renal failure in children was 50%. When I joined the resident staff of the Royal Alexandra Hospital for Children in 1966, children with renal disease were managed by general paediatricians. There was no active program for the treatment of children with acute or chronic renal failure. A small number of kidney biopsies had been performed by Dr Trefor Morgan who, together with Dr Denis Wade, had taught me the technique while I was a resident medical officer at the Royal Prince Alfred Hospital in the preceding year. With the guidance and support of Dr S.E.J. Robertson and Dr C. Lee, Honorary Medical Officers, and Dr R.D.K. Reye, Head of the Department of Pathology, I began performing kidney biopsies on children at the request of the paediatrician in charge. In the same year, encouraged again by Doctors Robertson and Lee, and by J.C.M. Friend and J. Brown, I introduced peritoneal dialysis for the treatment of children with acute renal failure, a technique which I had also been taught by Dr Trefor Morgan whilst I was a resident at Royal Prince Alfred Hospital. Dr Robertson encouraged me to present my experience in percutaneous renal biopsy in children at the Annual Meeting of the Australian Paediatric Association in 1968 and this study became the first paper I published in relation to disease of the urinary tract in children (1). In 1970 I was granted an Overseas Research Fellowship by the Post Graduate Foundation in Medicine, University of Sydney, to enable me to undertake a fellowship in the Department of Paediatrics at the University of Minnesota. I had the great fortune in undertaking studies in the new discipline of paediatric nephrology and related research under the guidance of Dr A. F. Michael, Dr R.L.Vernier and Dr A. Fish. I acquired the techniques of immunopathology and electron microscopy. On my return to Australia I established a Department of Nephrology at the Royal Alexandra Hospital for Children. I introduced immunofluorescent and electron microscopic studies for the kidney biopsies that I continued to perform and, with the support of Dr R.D.K. Reye, I provided the official reports of these studies until 1990. As a result these studies became part of the histopathologic service provided by the hospital. I continue to be consulted concerning the interpretation of some electron microscopic findings in renal tissue. With the assistance of Dr J.D. Harley I set up a laboratory in the Children’s Medical Research Foundation to continue and expand the studies I had commenced during my Fellowship. Establishing a dialysis and transplant program for children with end stage renal disease (ESRD) was extremely time consuming. At that time most children with ESRD died. The program was initially established jointly with the Renal Unit at Royal Prince Alfred Hospital in 1972 and eventually dialysis facilities were established at the Children’s Hospital using predominantly peritoneal dialysis. By 1978 the existence of the Unit was well known in the general community and articles appeared in the press. One prompted the late Sir Lorimer Dods, the first Professor of Paediatrics in Australia to write to me congratulating me on what I had achieved. He remarked “I have just read with special interest Shaun’s review in the SMH of some of your recent achievements in the field of renal failure in infancy and childhood and want to offer you my personal congratulations on all that you have achieved and are achieving in this area of paediatrics which, in my little world of yesterday, meant nothing more than progressive and unrelenting fatal illness”. Taking part in the development of a relatively new discipline led me to study a number of areas. I encouraged trainees to write reports concerning clinical observations and eventually I was joined by Fellows whom I encouraged and supported to study a number of different areas to ensure that children were being cared for in an environment of strong and open enquiry. This led to studies on investigations of chronic renal failure which Dr Elisabeth Hodson pursued and studies on urinary tract infection in small children for which Dr Jonathon Craig was awarded a PhD. As I had been a contributor and co-author in a number of these studies they have been included in my list of publications. As a result of this diversity I have listed the publications in 9 sections. The overall theme is to study diseases of the renal tract in children and treatments used to understand the processes and ensure the most effective treatment. Some published abstracts of papers presented at scientific meetings have been included to clarify invitations I received to prepare reviews and chapters on various subjects and my involvement in some conjoint studies. I was author or coauthor of several book chapters, reviews, editorials and certain published studies to which I was invited to contribute as a result of my primary studies and these I have included as “Derivative References”numbered 50-76.

Doctor of Medicine
Publications 1-49 represent studies that I have undertaken myself or conjointly over a 34 year period to investigate a variety of issues relating to diseases of the kidney and urinary tract in children. The studies were carried out at the Royal Alexandra Hospital for Children, Camperdown when I was Clinical Superintendent from 1968 - 1970; The Department of Paediatrics, University of Minnesota, Minneapolis, USA when I was Overseas Research Fellow of the Post Graduate Foundation in Medicine, University of Sydney, 1970 - 1972, then as Staff Physician in Nephrology at the Royal Alexandra Hospital for Children, Camperdown, 1972 - 1977, and then Head of that Department at the Hospital until 1995 and then as an Honorary Staff Specialist at that hospital. Some of the studies were done conjointly with members of the Renal Unit of Royal Prince Alfred Hospital where I hold an Honorary appointment and others conjointly with members of the Renal Unit of Prince Henry Hospital, Little Bay. I was appointed Clinical Associate Professor to the Department of Paediatrics and Child Health, University of Sydney in 1993. In 1966 paediatric nephrology was in the early phase of development as a medical subspecialty. There was no definitive textbook, the first was published in 1975 (Pediatric Nephrology, Ed. Mitchell I. Rubin. Williams and Wilkins.). In the preface to the 2nd edition of Renal Disease (Blackwell) in 1967 the editor D.A.K. Black noted that he had included a chapter on paediatric aspects which had been planned for the 1st edition in 1962 but ”it could not be arranged”. In the chapter on Renal Disease in Children the author, D.Macauly, comments that the mortality rate of acute renal failure in children was 50%. When I joined the resident staff of the Royal Alexandra Hospital for Children in 1966, children with renal disease were managed by general paediatricians. There was no active program for the treatment of children with acute or chronic renal failure. A small number of kidney biopsies had been performed by Dr Trefor Morgan who, together with Dr Denis Wade, had taught me the technique while I was a resident medical officer at the Royal Prince Alfred Hospital in the preceding year. With the guidance and support of Dr S.E.J. Robertson and Dr C. Lee, Honorary Medical Officers, and Dr R.D.K. Reye, Head of the Department of Pathology, I began performing kidney biopsies on children at the request of the paediatrician in charge. In the same year, encouraged again by Doctors Robertson and Lee, and by J.C.M. Friend and J. Brown, I introduced peritoneal dialysis for the treatment of children with acute renal failure, a technique which I had also been taught by Dr Trefor Morgan whilst I was a resident at Royal Prince Alfred Hospital. Dr Robertson encouraged me to present my experience in percutaneous renal biopsy in children at the Annual Meeting of the Australian Paediatric Association in 1968 and this study became the first paper I published in relation to disease of the urinary tract in children (1). In 1970 I was granted an Overseas Research Fellowship by the Post Graduate Foundation in Medicine, University of Sydney, to enable me to undertake a fellowship in the Department of Paediatrics at the University of Minnesota. I had the great fortune in undertaking studies in the new discipline of paediatric nephrology and related research under the guidance of Dr A. F. Michael, Dr R.L.Vernier and Dr A. Fish. I acquired the techniques of immunopathology and electron microscopy. On my return to Australia I established a Department of Nephrology at the Royal Alexandra Hospital for Children. I introduced immunofluorescent and electron microscopic studies for the kidney biopsies that I continued to perform and, with the support of Dr R.D.K. Reye, I provided the official reports of these studies until 1990. As a result these studies became part of the histopathologic service provided by the hospital. I continue to be consulted concerning the interpretation of some electron microscopic findings in renal tissue. With the assistance of Dr J.D. Harley I set up a laboratory in the Children’s Medical Research Foundation to continue and expand the studies I had commenced during my Fellowship. Establishing a dialysis and transplant program for children with end stage renal disease (ESRD) was extremely time consuming. At that time most children with ESRD died. The program was initially established jointly with the Renal Unit at Royal Prince Alfred Hospital in 1972 and eventually dialysis facilities were established at the Children’s Hospital using predominantly peritoneal dialysis. By 1978 the existence of the Unit was well known in the general community and articles appeared in the press. One prompted the late Sir Lorimer Dods, the first Professor of Paediatrics in Australia to write to me congratulating me on what I had achieved. He remarked “I have just read with special interest Shaun’s review in the SMH of some of your recent achievements in the field of renal failure in infancy and childhood and want to offer you my personal congratulations on all that you have achieved and are achieving in this area of paediatrics which, in my little world of yesterday, meant nothing more than progressive and unrelenting fatal illness”. Taking part in the development of a relatively new discipline led me to study a number of areas. I encouraged trainees to write reports concerning clinical observations and eventually I was joined by Fellows whom I encouraged and supported to study a number of different areas to ensure that children were being cared for in an environment of strong and open enquiry. This led to studies on investigations of chronic renal failure which Dr Elisabeth Hodson pursued and studies on urinary tract infection in small children for which Dr Jonathon Craig was awarded a PhD. As I had been a contributor and co-author in a number of these studies they have been included in my list of publications. As a result of this diversity I have listed the publications in 9 sections. The overall theme is to study diseases of the renal tract in children and treatments used to understand the processes and ensure the most effective treatment. Some published abstracts of papers presented at scientific meetings have been included to clarify invitations I received to prepare reviews and chapters on various subjects and my involvement in some conjoint studies. I was author or coauthor of several book chapters, reviews, editorials and certain published studies to which I was invited to contribute as a result of my primary studies and these I have included as “Derivative References”numbered 50-76.

The aim of the experiments reported in the present work was: first, to generate a rat model of lithium-induced nephrogenic diabetes insipidus (NDI), and, second, to use this to test the hypothesis that the effects of lithium were far more reaching than merely the inhibition of vasopressin induced translocation and synthesis of the water channel protein AQP2. Specifically, the effect of lithium on the abundance and distribution of the other water channel proteins, AQP1, AQP3 and AQP4 was investigated. It was found that AQP3 protein abundance was significantly reduced in the renal medulla while AQP4 was not affected. In addition, it was further hypothesized that, given the known effects of lithium on the urea transporter UT-A1 and on sodium channels and transporters, the renal medullary osmotic gradient would be dissipated by lithium. This was examined indirectly by determining the amounts of organic osmolytes in the renal medulla of rats with lithium-induced NDI. Myo-inositol was found to be 85 � 9 mmol kg⁻1 protein in the NDI rats, a reduction of 38% compared with control values, sotbitol fell from 35� 9 mmol kg⁻� in the control rats to 2.5 � 0.5 mmol kg⁻�, and glycerophosphorylcholine levels in the experimental animals were 91 � 18 mmol kg⁻� protein compared with 372 � 72 mmol kg⁻� in the controls. In addition, betaine decreased to 38 � 2 mmol kg⁻� protein from 69 � 10 mmol kg⁻� protein in the control. The urea content of the medulla was found to have fallen from 2868 � 558 mmol kg⁻� protein to 480 � 105 mmol kg⁻� protein. These data indicated that indeed the medullary osmotic gradient, the driving force for AVP-dependent fluid reabsorption in the kidney was greatly reduced during lithium-induced NDI. Thirdly, it was proposed that the sodium-channel blocker, amiloride, by acting to prevent lithium entry into the cells of the collecting duct, should ameliorate or abolish the adverse effects of lithium on the kidney. Treatment of rats with established NDI, with amiloride, reversed to a large extent the reduction in aquaporin protein expression and re-established the medullary osmotic gradient, as assessed by the ability of treated rats to concentrate their urine, and by the rise in amounts of medullary osmolytes. Administration of 0.5 mmol l⁻� amiloride to lithium-treated rats led to medullary AQP2 and AQP3 protein abundance increasing by 82% � 16% and 110% � 4% of the control level respectively. The content of urea in the medulla also increased to 2474 � 557 mmol kg⁻� protein. Finally, since in humans it is known that the chronic effect of lithium on the kidney is to cause cortical fibrosis and renal failure, microarray studies were commenced to look for evidence of early changes in gene activity in response to lithium-administration. The results showed that 77 genes were either up- or down-regulated, in particular, genes that are involved in the apoptosis pathway. In the light of these results it is plausible to suggest that the acute renal effects of lithium to induce NDI can be effectively mitigated, and reversed, by administration of amiloride. Whether this can serve to offset the chronic effects of lithium on the kidney awaits further investigation.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Pacientes com Lesão Renal Aguda (LRA) em Diálise Peritoneal Contínua (DPC) ou Hemodiálise Diária (HD) podem apresentar alterações da função pulmonar relacionadas à hipóxia, retirada de líquidos ou toxinas uremias e, no caso da DPC, ao aumento da pressão intra-abdominal (PIA). Os objetivos deste estudo foram realizar avaliação respiratória de pacientes com LRA dialítica internados em Unidades de Terapia Intensiva (UTI) em Ventilação Mecânica Invasiva (VMI), submetidos à DPC e ou HD e avaliar a PIA nos pacientes em DPC. Foi realizado estudo prospectivo descritivo em que foram avaliadas complacência estática (Cest, expresso em mL/cmH2O), resistência do sistema respiratório (Rsr, expresso em cmH2O/L/s), relação PaO2/FiO2 e FiO2 (expresso em %) em pacientes submetidos a DPC e HD e PIA (expresso em mmHg) naqueles em DPC. Os pacientes do Grupo DPC foram avaliados nos momentos M0 (pré-diálise/cavidade vazia), M1(pós-infusão do dialisato da 1ª sessão de diálise/cavidade cheia), M2, M3 e M4 (após cada sessão de DP/cavidade vazia) e do Grupo HD nos momentos M1, M3 e M5 (pré-diálise) e M2, M4 e M6 (pós-diálise). Análise Estatística: Para comparar as variáveis de Cest, Rsr, PaO2/FiO2, FiO2 e PIA no tempo foi utilizado o modelo Anova de medidas repetidas e comparações múltiplas ajustado por Tukey ou o modelo de medidas repetidas usando uma distribuição assimétrica (Gama) através do procedimento GENMOD pela opção DIFF. Nível de significância de 5%. NO grupo DPC foram avaliados 20 pacientes em 44 sessões. A média de idade foi de 73,2± 11 anos, o APACHE II foi 24,1±4 e o ATN-ISS foi 0,64±23. A Cest diminuiu após a infusão do dialisato (cavidade abdominal cheia) em relação ao Pré- Diálise/cavidade abdominal vazia (M0= 36± 14,7 e M1= 33,85± 13,8 ml/cmH2O; p=ns) e após as trocas do dialisato...
Acute kidney injury (AKI) patients on continuous peritoneal dialysis (CPD) or daily hemodialysis (HD) may show changes in lung function related to hypoxia or removal of uremic toxins and fluids and in those undergoing PD also due to increased intraabdominal pressure (IAP). Objective of this study was to evaluate respiratory mechanic of critical AKI patients undergoing invasive mechanical ventilation (IMV) and treated by CPD or HD and assessment the IAP in patients on CPD. A prospective descriptive study was performed to determine static compliance (Cest expressed in mL/cmH2O), respiratory system resistance (Rsr expressed in cmH2O/L/s), PaO2/FiO2 ratio and Fi2O (expressed in %) in patients undergoing HD and CPD and PIA (expressed in mmHg) in those on CPD. CPD group was evaluated at M0 (pre dialysis/ empty cavity), M1 (post-infusion of the dialysate / filled cavity), M2, M3 and M4 (after each session of DP / empty cavity ) and the HD group at M1, M3 and M5 (pre-dialysis) and M2, M4 and M6 (post-dialysis). Statistical Analysis: To compare the variables Rsr, PaO2/FiO2, FiO2 and PIA was used ANOVA for repeated measures and Tukey adjusted for multiple comparisons or repeated measures model GENMOD procedure for the DIFF option. Significance level of 5%. Twenty patients (44 sessions) were evaluated in CPD group. Age was 73.2 ± 11 years, APACHE II was 24.1 ± 4 and ATN-ISS was 23 ± 0.64. Cest decreased after infusion of the dialysate (abdominal cavity filled) compared to the Pre-Dialysis / empty abdominal cavity (M0 = M1 and 36 ± 14.7 ± 13.8 mL/cmH2O = 33.85, p = ns) and increased progressively after exchanges of dialysate (empty abdominal cavity) (M2 = 38.42 ± 13.4; M3= 40.6± 13.5; and M4 = 53.4 ± 21.9 mL/cmH2O; M4 vs M0: p = 0.0018; M4 vs M1: p = 0.0004; M4 vs M2: p = 0.0017 M4 vs M3: p = 0.04). PIA... (Complete abstract click electronic access below)

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Introdução: A mortalidade de pacientes com sepse e lesão renal aguda (LRA) é inaceitavelmente elevada, com necessidade de medidas de prevenção. Faltam estudos brasileiros que mostrem esta incidência em salas de emergências clínicas (SEC) e identifiquem fatores de risco para o seu desenvolvimento, além de marcadores precoces de diagnóstico e prognóstico. Dentre eles, encontra-se o NGAL, que é um biomarcador sérico e urinário (u) promissor de detecção precoce de LRA. Objetivos: Este trabalho teve como objetivo principal avaliar a eficácia do NGALu como preditor diagnóstico e prognóstico da LRA associada à sepse em pacientes admitidos em SEC. Metodologia: Estudo prospectivo de pacientes admitidos na SEC com diagnóstico de sepse durante o período de 01 de fevereiro de 2013 a 31 de maio de 2014. Para cada paciente foi aplicado um protocolo com dados clínicos e laboratoriais. A avaliação da função renal foi realizada por dosagem de creatinina sérica e verificação de débito urinário desde a admissão até o desfecho do quadro (resolução ou óbito). O NGALu foi dosado nas primeiras 24h de admissão (1), entre 24-48h (2) e no momento do diagnóstico de LRA (3). Os resultados foram apresentados por regressão logística e área sob a curva roc para determinar a capacidade do NGALu discriminar o diagnóstico e prognóstico da LRA. Resultados: Foram incluídos 168 pacientes, sendo que 72% tiveram diagnóstico de LRA. Na regressão logística, a idade >65 anos, choque séptico, necessidade de ventilação mecânica (VM) e o NGALu 2 foram identificados como fatores associados à LRA. Quanto à precisão, NGALu 1 e 2, assim como a relação NGAL/Cru 1 e 2 apresentaram área sob a curva ROC para LRA >0,7, com sensibilidade entre 0,63 e 0,75. Os fatores de risco identificados para o óbito foram choque séptico, presença de LRA AKIN 3 e APACHE II > 20. Como preditores de óbito, NGALu 1 e 2 e a relação NGALu/Cru 1 e 2,...
Background: The mortality of septic patients and AKI is inaceptable high, showing the need for preventive measures. There are few Brazilian studies showing the incidence of AKI in clinical emergencies rooms (ER) and identify risk factors for its development, and early markers of diagnosis of AKI and prognosis of patients. NGAL is a serum and urinary (u) promising biomarker for early detection of AKI. Objectives: This study aimed to evaluate the efficacy of uNGAL as a diagnostic and prognostic predictor of AKI associated with sepsis in patients admitted to the ER. Methodology: We prospectively studied patients admitted to the ER diagnosed with sepsis during the period of February 1, 2013 to May 31, 2014. For each patient, a protocol was developed containing clinical and laboratory data from the patients admission to the discharge of the hospital (resolution or death). The assessment of renal function was performed daily by serum creatinine, urine output, and dosage of uNGAL within the first 24 hours after admission (1), between 24-48 h (2) and at moment of AKI diagnosis (3). The results were presented using descriptive statistics of the study population and different statistical tests according to the study objectives. Logistic regression and ROC area under curve was used to determine the ability of uNGAL to discriminate the AKI diagnosis and prognosis of septic patients. Results: One hundred eight patients were included, of which 72% were diagnosed with AKI. In logistic regression, age> 65 years, septic shock, need for mechanical ventilation (MV) and the uNGAL 2 were identified as factors associated with AKI. Regarding the accuracy, uNGAL 1 and 2, as well as uNGAL / uCr 1 and 2 showed an area under the ROC curve for AKI> 0.7, with sensibility between 0.63 and 0.75. The risk factors identified in the logistic regression for death were septic shock, presence of AKI AKIN 3 and APACHE II> 20. As predictors of death, the precision of uNGAL1, ...

Orientador: Daniela Ponce
Coorientador: André Luis Balbi
Banca: Luís Gustavo Modelli de Andrade
Banca: Ginivaldo Victor Ribeiro do Nascimento
Resumo: Introdução: A mortalidade de pacientes com sepse e lesão renal aguda (LRA) é inaceitavelmente elevada, com necessidade de medidas de prevenção. Faltam estudos brasileiros que mostrem esta incidência em salas de emergências clínicas (SEC) e identifiquem fatores de risco para o seu desenvolvimento, além de marcadores precoces de diagnóstico e prognóstico. Dentre eles, encontra-se o NGAL, que é um biomarcador sérico e urinário (u) promissor de detecção precoce de LRA. Objetivos: Este trabalho teve como objetivo principal avaliar a eficácia do NGALu como preditor diagnóstico e prognóstico da LRA associada à sepse em pacientes admitidos em SEC. Metodologia: Estudo prospectivo de pacientes admitidos na SEC com diagnóstico de sepse durante o período de 01 de fevereiro de 2013 a 31 de maio de 2014. Para cada paciente foi aplicado um protocolo com dados clínicos e laboratoriais. A avaliação da função renal foi realizada por dosagem de creatinina sérica e verificação de débito urinário desde a admissão até o desfecho do quadro (resolução ou óbito). O NGALu foi dosado nas primeiras 24h de admissão (1), entre 24-48h (2) e no momento do diagnóstico de LRA (3). Os resultados foram apresentados por regressão logística e área sob a curva roc para determinar a capacidade do NGALu discriminar o diagnóstico e prognóstico da LRA. Resultados: Foram incluídos 168 pacientes, sendo que 72% tiveram diagnóstico de LRA. Na regressão logística, a idade >65 anos, choque séptico, necessidade de ventilação mecânica (VM) e o NGALu 2 foram identificados como fatores associados à LRA. Quanto à precisão, NGALu 1 e 2, assim como a relação NGAL/Cru 1 e 2 apresentaram área sob a curva ROC para LRA >0,7, com sensibilidade entre 0,63 e 0,75. Os fatores de risco identificados para o óbito foram choque séptico, presença de LRA AKIN 3 e APACHE II > 20. Como preditores de óbito, NGALu 1 e 2 e a relação NGALu/Cru 1 e 2,...
Abstract: Background: The mortality of septic patients and AKI is inaceptable high, showing the need for preventive measures. There are few Brazilian studies showing the incidence of AKI in clinical emergencies rooms (ER) and identify risk factors for its development, and early markers of diagnosis of AKI and prognosis of patients. NGAL is a serum and urinary (u) promising biomarker for early detection of AKI. Objectives: This study aimed to evaluate the efficacy of uNGAL as a diagnostic and prognostic predictor of AKI associated with sepsis in patients admitted to the ER. Methodology: We prospectively studied patients admitted to the ER diagnosed with sepsis during the period of February 1, 2013 to May 31, 2014. For each patient, a protocol was developed containing clinical and laboratory data from the patients admission to the discharge of the hospital (resolution or death). The assessment of renal function was performed daily by serum creatinine, urine output, and dosage of uNGAL within the first 24 hours after admission (1), between 24-48 h (2) and at moment of AKI diagnosis (3). The results were presented using descriptive statistics of the study population and different statistical tests according to the study objectives. Logistic regression and ROC area under curve was used to determine the ability of uNGAL to discriminate the AKI diagnosis and prognosis of septic patients. Results: One hundred eight patients were included, of which 72% were diagnosed with AKI. In logistic regression, age> 65 years, septic shock, need for mechanical ventilation (MV) and the uNGAL 2 were identified as factors associated with AKI. Regarding the accuracy, uNGAL 1 and 2, as well as uNGAL / uCr 1 and 2 showed an area under the ROC curve for AKI> 0.7, with sensibility between 0.63 and 0.75. The risk factors identified in the logistic regression for death were septic shock, presence of AKI AKIN 3 and APACHE II> 20. As predictors of death, the precision of uNGAL1, ...
Mestre

The aim of this research was to perform exclusion on a rare form of hereditary autosomal dominant polycystic kidney disease (ADPKD). To-date, two genes for ADPKD have been identified: PKDI which has been localized to the short arm of chromosome 16 and PKD2 which has been localized to the long arm of chromosome 4. However, a small number of families have been reported that have not shown linkage to either of these two loci, thus suggesting the existence of at least one additional locus (PKD3). Two families that are affected with ADPKD and do not show linkage to PKDI or PKD2 have participated in this study. Both families are of Bulgarian origin and between them contain 9 affected individuals. Even though these families are small, they are large enough to exclude a large proportion of the genome as the location of the PKD3 gene. The availability of these families and the discovery of other non PKD1/PKD2 families has provided a rare opportunity to perform exclusion mapping of the PKD3 gene which will eventually lead to mapping and cloning of this gene. A systematic search of the human genome was performed using polymorphic markers (from the Research Genetics screening set version 4a) which span the human genome at an average distance of 16cM. The results were then analysed statistically using the computer programs EXCLUDE, LINKAGE and GENEHUNTER. From this study the highest Lod score obtained was a multipoint Lod score of 2.95 on 22q 11.21 at marker D22S446. Two other regions also produced relatively high Lod scores, the first being on 4q22.1 at marker D4S1647 which produced a Lod score of 1.42 and the second region being on 11p15.2 at marker D11S902 which produced a Lod score of 1.41. These results provide a strong indication as to the location of the PKD3 gene however, before linkage can be claimed with any degree of certainty the sample size must be increased with the addition of other non PKD1/PKD2 families. This increases the possibility of obtaining a Lod score of 3.00 or greater and thus proving linkage to the PKD3 gene.

Introduction et buts de la thèse

La survie du patient et du greffon se sont nettement améliorées depuis les débuts de la transplantation rénale. Les recommandations de pratiques cliniques basées sur l’évidence aident les cliniciens à améliorer la prise en charge standardisée des patients. Cependant, de nombreux programmes de recherche sont actuellement axés sur la découverte de biomarqueurs qui peuvent prédire les différents résultats chez les patients transplantés rénaux. Ces biomarqueurs sont nécessaires pour personnaliser la gestion et le traitement des patients.

Le but des travaux résumés dans cette thèse est d'évaluer l'impact potentiel de plusieurs facteurs biologiques acquis et génétiques spécifiques sur les résultats après la transplantation rénale, en particulier les facteurs de thrombophilie et les polymorphismes génétiques associés au diabète post-transplantation.

1. Facteurs de thrombophilie

Les patients en insuffisance rénale terminale présentent des anomalies complexes de la coagulation, dont les mécanismes sous-jacents ne sont pas connus à ce jour. La thrombose des vaisseaux du greffon et les événements thromboemboliques comme la thrombose veineuse profonde et / ou l’embolie pulmonaire sont des complications graves, mais relativement rares après transplantation rénale. Au cours de la dernière décennie, plusieurs études ont évalué l'impact des facteurs de thrombophilie sur les résultats après la transplantation rénale, tels que les événements thrombo-emboliques, y compris la thrombose de l’artère ou la veine du greffon, le rejet aigu, les événements cardiovasculaires ou la survie du greffon. Cependant, les limitations méthodologiques et l'hétérogénéité de ces études rendent les conclusions ou les recommandations difficiles. D’autre part, la prévalence exacte des facteurs de thrombophilie dans la population de patients en insuffisance rénale terminale et la correction éventuelle de ces facteurs après transplantation ne sont pas connues. Dans ce contexte, nous avons réalisé une étude prospective afin d’évaluer l’impact d’un panel de 11 facteurs de thrombophilie testés le jour de la transplantation et 1 mois plus tard, sur les événements thrombo-emboliques et le rejet aigu durant la première année de greffe [58]. Nous avons également évalué la prévalence de 7 facteurs de thrombophilie non-génétiques chez les patients en insuffisance rénale terminale et le taux de correction après la transplantation rénale dans une cohorte de 215 patients [59].

2. Diabète post-transplantation

Le diabète post-transplantation est une complication métabolique grave et fréquente après la transplantation. Les patients transplantés rénaux souffrant d’un diabète post-transplantation ont un risque plus élevé d'événements cardiovasculaires majeurs, de décès et d’échec de greffe. Une étude prospective rapporte une incidence de 20,5% durant les six premiers mois de greffe rénale, en utilisant les critères stricts de l'ADA (American Diabetes Association). La plupart des facteurs de risque identifiés sont communs avec le diabète de type 2 dans la population générale: l'âge, les antécédents familiaux, l’ethnie (africaine et hispanique), l'indice de masse corporelle élevé, une sérologie hépatite C positive et la présence d’un syndrome métabolique. Certains traitements immunosuppresseurs sont des facteurs de risque de diabète post-transplantation spécifiques et modifiables. Les inhibiteurs de la calcineurine sont diabétogènes et il a été clairement montré que le tacrolimus est plus diabétogène que la cyclosporine. En se basant sur ces données, nous avons remplacé le tacrolimus par la cyclosporine chez une série de patients ayant développé un diabète post-transplantation sous tacrolimus. Nous avons évalué rétrospectivement l’efficacité et la sécurité de cette approche [60]. Nous avons également élaboré des recommandations pour la prise en charge du diabète post-transplantation sur base de notre expérience et des études publiées [62].

La susceptibilité génétique du diabète post-transplantation a été étudiée par des approches «gènes candidats », mais les faibles effectifs et l'absence de réplication dans des cohortes indépendantes rendent les conclusions difficiles. Les études pan-génomiques de type « genome wide association study (GWAS) apportent un éclairage neuf sur les origines génétiques du diabète de type 2. Plus de 10 loci de susceptibilité ont été associés au diabète de type 2 dans la population générale, avec des odds ratio (OR) allant de 1.10 à 1.20, excepté un variant commun du gène TCF7L2 pour lequel le risque de la maladie augmente de 37% par allèle à risque. Nous avons utilisé une approche gène candidat en sélectionnant 11 variants génétiques associés au diabète de type 2 à travers ces GWAS et nous avons évalué leur association avec le risque de diabète post-transplantation durant les 6 premiers mois post-transplantation, dans une large cohorte de Caucasiens (N = 1076) [61].

Méthodologie générale

L’unité de transplantation rénale de l'Hôpital Erasme (Université Libre de Bruxelles) a créé une base de données clinique incluant les patients transplantés depuis 1964 dans l'institution et une biocollection (ADN et sérum) depuis 2001. En outre, depuis 2007, l'unité de transplantation rénale de l'Hôpital Erasme a développé une collaboration avec d'autres centres européens de transplantation rénale (CHU de Tours, CHU de Limoges, CHU de Brest, CHU de Saint-Étienne, CHRU de Lille, CHU de Poitiers et CHU de Bordeaux actuellement). Nous avons actuellement collecté les données cliniques et l’ADN de plus de 4000 receveurs d'allogreffe rénale.

Résultats

1. Facteurs de thrombophilie

Nous avons enrôlé prospectivement 320 greffes rénales consécutives correspondant à 317 patients greffés dans notre institution entre 2001 et 2006. Onze facteurs de thrombophilie ont étés dosés le jour de la transplantation. Dix patients ont étés exclus en raison de valeurs manquantes pour plus de 3 facteurs. Tous nos patients ont reçu de l’acide acétylsalicylique en prophylaxie, débuté juste avant la greffe. Le taux d'événements thromboemboliques et/ou de rejet aigu durant la première année post-transplantation (critère d’évaluation primaire composite) était de 16,7% chez les patients sans facteur de thrombophilie (N = 60) et de 17,2% chez ceux ayant au moins un facteur de thrombophilie (N = 250) (P=NS) le jour de la greffe. L'incidence du critère d’évaluation primaire était similaire chez les patients sans facteur de thrombophilie et ceux avec au moins deux (N = 135), ou au moins trois (n = 53) facteurs (16,3% et 15,1% respectivement, P=NS) et chez les patients avec au moins un facteur persistant 1 mois après la greffe (15,7%, P=NS). Aucun des facteurs de thrombophilie individuels présents le jour de la transplantation n’était associé au critère d’évaluation primaire. L'incidence des événements cardio-vasculaires à 1 an, la créatinine sérique à 1 an, la survie de greffe actuarielle à 4 ans n’étaient pas influencés par la présence d’au moins un facteur de thrombophilie le jour de la greffe (P= NS).

La prévalence des facteurs de thrombophilie était significativement plus élevée chez les patients dialysés que chez les patients non encore dialysés le jour de la greffe (74% vs 52,4%, P =0,03). La prévalence était similaire chez les patients hémodialysés et en dialyse péritonéale (P=NS). Un mois après la transplantation, la prévalence globale des facteurs de thrombophilie a chuté de 74,4% à 44,7% (P <0,001). La plupart des facteurs de thrombophilie avaient disparus après la transplantation.

2. Le diabète post-transplantation

Nous avons analysé rétrospectivement les paramètres du métabolisme glucidique chez 54 patients greffés rénaux traités par tacrolimus et développant un diabète post-transplantation. Trente-quatre patients ont été convertis à la cyclosporine alors que 20 patients ont poursuivi le tacrolimus (groupe contrôle). Après la conversion, le taux de rémission du diabète post-transplantation était de 42% (IC 95% :24-59%) 1 an après la conversion versus 0% dans le groupe contrôle (P=0,001). La conversion

était sûre en termes de fonction du greffon, de rejet aigu, de survie des patients et du greffon.

Dans notre étude multicentrique (Hôpital Erasme-Bruxelles, CHU de Tours, CHU de Limoges et CHRU de Lille), nous avons enrôlé 1477 patients greffés successivement. Parmi les 1229 patients éligibles pour l’étude, 1076 étaient Caucasiens (analyses primaires). Un total de 118 patients, soit 11% des Caucasiens ont développé un diabète post-transplantation durant les 6 premiers mois de greffe. En analyse multi-variée, le variant rs7903146 de TCF7L2 était indépendamment associé au diabète post-transplantation (OR = 1,60 pour chaque allèle T, P = 0,002). Les autres facteurs de risque indépendants étaient: l'âge du receveur, l’indice de masse corporelle au moment de la greffe, l'utilisation du tacrolimus et la survenue d'un épisode de rejet aigu traité par corticoïdes.

Conclusions

Les facteurs de thrombophilie sont très fréquents au stade terminal de l'insuffisance rénale et sont corrigés dans la grande majorité après la transplantation rénale. Cela suggère que la plupart des facteurs sont acquis et associés à l'urémie et / ou la dialyse. En outre, notre étude prospective n’a pas démontré d’impact des facteurs de thrombophilie détectés de manière systématique avant la transplantation sur les résultats après transplantation rénale, dans une population recevant un régime immunosuppresseur moderne et de l’acide acétylsalicylique en prophylaxie.

L’effet diabétogène du tacrolimus est réversible. Nos résultats suggèrent une amélioration significative du métabolisme glucidique après la conversion à la cyclosporine chez les patients transplantés rénaux atteints de diabète post-transplantation sous tacrolimus.

Le diabète post-transplantation et le diabète de type 2 partagent des facteurs de risque communs, dont un variant du gène TCF7L2. La place de ce type de biomarqueur dans la prédiction de la survenue du diabète post-transplantation et dans les stratégies de modification d’immunosuppression doit faire l’objet d’évaluations prospectives.

Doctorat en Sciences médicales
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O aumento sérico da creatinina em 0,3mg/dL define o termo lesão renal aguda (LRA) e associa-se a maior incidência de mortalidade pós-operatória em pacientes submetidos a revascularização do miocárdio. Os estudos clínicos quanto à influência da dexmedetomidina (DEX) sobre a função renal ainda são escassos. Avaliou-se a LRA no pós operatório de revascularização do miocárdio com e sem circulação extracorpórea (CEC) quando se anestesiou com DEX. Neste estudo, retrospectivo, fez-se análise seriada da creatinina sérica (CrS) até 48h de pós-operatório de 286 pacientes submetidos a revascularização do miocárdio para avaliar a incidência de LRA. Testou-se a homogeneidade entre os grupos, avaliando-se os pacientes separadamente quanto ao uso de CEC e de DEX. Cada paciente foi avaliado em relação à sua concentração sanguínea de creatinina nos períodos pré-operatório, pós-operatório imediato, de 24h e de 48h. Em cada período foi efetuada a comparação da concentração de creatinina com a concentração no pré-operatório. Se em pelo menos um dos períodos esta comparação indicou aumento de creatinina≥0,3 mg/dL, o paciente foi classificado como tendo LRA. Foi também avaliado o risco de LRA em pacientes com creatinina sanguínea pré-operatória alterada (valores entre 1,1 a 2,0mg/dL para mulheres ou 1,3 a 2,0mg/dL para homens) em comparação com os pacientes com creatinina normal.Os resultados foram homogêneos quanto a peso, idade e creatinina alterada no pré-operatório e os pacientes que fizeram uso de DEX e foram submetidos a CEC apresentaram maior incidência de LRA, com p=0,043. Dentre aqueles que não foram submetidos a CEC, houve maior incidência de LRA após DEX, porém com p=0,066.O uso da DEX no intraoperatório aumentou a incidência de LRA no pós-operatório de revascularização do miocárdio de pacientes submetidos a CEC
The increase of 0.3mg/dL in serum creatinine defines the term acute kidney injury (AKI) and is associated with higher incidence of postoperative mortality in patients undergoing coronary artery bypass grafting surgery (CABG). Clinical studies regarding the influence of dexmedetomidine (DEX) on renal function are scarce. We evaluated the LRA in postoperative of patients submitted to CABG with and without cardiopulmonary bypass (CPB) under anesthesia with DEX. In this retrospective study it was made serial analysis of serum creatinine (SCr) until 48h after the surgery of 286 patients undergoing CABG under DEX to evaluate the incidence of AKI. We tested the homogeneity among groups, evaluating patients separately for the use of CPB and DEX. Each patient was evaluated with respect to their blood concentration of creatinine in the preoperative and postoperative: early, 24h and 48h. In each period, it was compared the creatinine concentration with creatinine concentration preoperatively. If at least in one of the periods this comparison showed increased creatinine ≥ 0.3mg/dL, the patient was classified as having AKI. It has also assessed the risk of AKI in patients with preoperative blood creatinine changed: values between 1.1 to 2.0mg/dL for females or 1.3 to 2.0mg/dL for men compared with patients with normal creatinine concentration. The results were homogeneous for weight, age and creatinine concentration altered to 2.0mg/dL preoperatively. Patients who used DEX and underwent CPB had a higher incidence of AKI, with p = 0.043. Among those who were not undergoing CPB, there was a higher incidence of AKI after DEX, but with p = 0.066. Conclusion. The use of intraoperative DEX increased the incidence of AKI in the postoperative myocardial revascularization in patients undergoing CPB