INTRODUÇÃO: A hipertensão renovascular (HRV) decorrente da estenose de artéria renal (EAR) é uma patologia potencialmente curável, mas os benefícios da revascularização não são alcançados por todos porque selecionar pacientes com base nos critérios clínicos ou angiográficos pode não ser suficiente para se obter o sucesso clínico. Existe um grande interesse em se desenvolver exames para detectar a presença de EAR e avaliar seu significado funcional. OBJETIVOS: avaliar se a redução da Taxa de Filtração Glomerular (TFG) medida com EDTA-51Cr após o uso de captopril consegue diferenciar pacientes hipertensos com EAR daqueles sem estenose da artéria e avaliar se existe correlação entre as variações da TFG e a evolução de pacientes submetidos a diferentes tratamentos. MÉTODOS: Foram estudados 41 pacientes com hipertensão arterial de difícil controle que foram divididos em dois grupos: GP: 21 pacientes com EAR e GH: 20 pacientes sem EAR. Os pacientes foram submetidos à medida de TFG com EDTA-51Cr pré e após a administração do captopril. Os pacientes do GP realizaram simultaneamente cintilografia com DMSA-99mTc para avaliação da função renal diferencial. Os pacientes com estenose de artéria renal foram subdivididos de acordo com o tratamento recebido: clínico (GP-CL) ou por intervenção (GP-I). As medidas das TFGs antes e após o captopril foram comparadas entre os grupos. Foi também, investigado se a relação pré/pós captopril tinha correlação com a resposta clínica dos pacientes. RESULTADOS: a média da TFG (ml/min./1,73m2) no total de pacientes estudados, foi de 56,7±26,5 na fase pré-captopril e 47,0±24,4 após o captopril. A modificação da TFG determinada pelo captopril,foi avaliada pela relação da filtração glomerular pré/pós-captopril. A média da relação TFG pré/pós-captopril foi 1,36 ±0,54 no grupo total de pacientes e quando foi feita a comparação entre a TFG pré e pós-captopril, houve uma redução significativa (p= 0,016). O GH mostrou relação média da TFG pré/pós-captopril de 1,13, valor significativamente menor que o GP que teve a relação média de 1,57 (p= 0,007). Quando foi avaliada a variação da TFG após o captopril nos dois grupos não foi observada diferença estatisticamente significativa no GH (p=0,68), mas observou-se diferença significativa no GP (p<0,001). No total, 15 pacientes apresentaram melhora dos seus níveis pressóricos, sendo oito do grupo de intervenção e sete do grupo clinico, não havendo diferença estatisticamente significativa em relação à melhora clínica entre os dois grupos (p=0,36). Quando comparamos os pacientes com e sem melhora clínica não se observou diferença significativa na TFG basal (p=0,09) ou na relação TFG pré/pós-captopril (p=0,74). A função renal diferencial obtida pelo DMSA-99mTc pré e pós captopril não mostrou diferença estatisticamente significativa nos rins com e sem estenose, (p=0.09). CONCLUSÃO: O captopril acarreta uma redução significativa da TFG e esta redução é mais acentuada em pacientes com EAR, mas não houve correlação entre as mediadas da TFG e a evolução clínica dos pacientes / INTRODUCTION: Renovascular hypertension (RVH) resulting from renal artery stenosis (RAS) is a potential curable pathology, but the revascularization benefits are not reached among all patients because selecting patients on the basis of clinical and angiographic criteria may not be sufficient to achieve clinical success. There has been increasing interest in developing screening tests capable of accurately detecting the presence of RAS and also of evaluating its functional consequences PURPOSE: the purpose of this study was to evaluate if captopril induced changes in 51Cr-EDTA clearance could be used to differentiate between hypertensive patients with and without renal artery stenosis and to investigate if there was a correlation between these changes and patients clinical response to therapy. METHODS: 41 patients with poor-controlled severe hypertension were studied. Patients were divided into two groups: GP=patients with renal artery stenosis (n=21), and GH=patients without renal artery stenosis (n=20). They were submitted to a Glomerular Filtration Rate (GFR) measurement with EDTA-51Cr pre and post captopril administration. The GP patients were submitted simultaneously to 99mTc-DMSA scintigraphies to estimate individual renal function. GP patients were further subdivided according to the treatment strategy: optimization of clinical treatment (GP-Cl) and interventional procedures (GP-I). The GFRs before and after captopril administration were compared between the groups. It was also investigated if baseline to post-captopril GFR ratio had a correlation to clinical response of patients. RESULTS: The GFR average (ml/min./1,73m2) on the total patients, was 56,7±26,5 on pre-captopril phase and 47,0±24,4 post captopril. The GFR alteration determinated by captopril was evaluated by Baseline/post-captopril GFR ratio. Baseline/post-captopril GFR mean ratio was 1,36 in total patients and the GFR had a significant decrease after captopril administration (p value 0.016). Baseline/post-captopril GFR mean ratio in GH was 1.13, value significantly lower than the GP which had the average relation of 1,57 (p= 0,007). When GFR pre and post-captopril was compared among the two groups separately, there was no significantly difference on the GH (p=0,68), but a expressive difference was observed on GP (p<0,001). 15 patients had a clinical response to the treatment. Clinical response was observed in 8/10 patients from GP-I and 7/11 from GP-Cl and there was not observed a significantly difference between the two groups (p=0,36). Comparing the groups with or without clinical improvement there was not a significantly difference on the GRF baseline (p=0,09) or on or baseline/post-captopril ratio (p=0,74). When evaluating the differential renal function obtained by pre and post-captopril DMSA-99mTc, significantly difference was not observed (p=0.09) for the kidneys with or without stenosis. CONCLUSION: captopril induced a decrease in GFR of hypertensive patients and it is more pronounced in patients with renal artery stenosis, but no correlation was observed between captopril induced decrease in GFR and clinical response of patients submitted to interventional or clinical treatment

Diabetes mellitus is a metabolic disease largely due to lifestyle and nutritional imbalance, resulting in insulin resistance, hyperglycemia and vascular complications. Diabetic kidney disease (DKD) is a major cause of end-stage renal failure contributing to morbidity and mortality worldwide. Therapeutic options to prevent or reverse DKD progression are limited. Endothelial and glomerular filtration barrier (GFB) dysfunction and sterile inflammation are associated with DKD. Neutrophil extracellular traps (NETs), originally identified as an innate immune mechanism to combat infection, have been implicated in sterile inflammatory responses in non-communicable diseases. However, the contribution of NETs in DKD remains unknown. Here, we show that biomarkers of NETs are increased in diabetic mice and diabetic patients and that these changes correlate with DKD severity. Mechanistically, NETs promote NLRP3 inflammasome activation and glomerular endothelial dysfunction under high glucose stress in vitro and in vivo. Inhibition of NETs (PAD4 inhibitor) ameliorate endothelial dysfunction and renal injury in DKD. Taken together, NET-induced sterile inflammation promotes diabetes-associated endothelial dysfunction, identifying a new pathomechanism contributing to DKD. Inhibition of NETs may be a promising therapeutic strategy in DKD.

La presente tesis tuvo como fin demostrar los cambios en la filtración glomerular y respuesta natriuretica, asociados a una dieta hiperprotéica crónica, con una exposición final de sobrecarga salina. Las variables a evaluar fueron los cambios en la reserva funcional renal y natriuresis. Se realizó un estudio analítico experimental en 18 ratas macho adultas Holtzman entre 8 y 14 semanas de vida en un periodo de estudio de 12 semanas. La distribución inicial fue de 3 grupos. El primer grupo recibió una dieta hiperprotéica de fuente animal de 30% (n:6) y fue comparado con una normoprotéica de fuente animal de 18% (n:6), un tercer grupo recibió una dieta hiperprotéica de fuente vegetal de 30% (n:6). Las dietas fueron isocalóricas y normosódicas (0.25%). Desde la semana 8, cada grupo fue dividido en 3 ratas cada uno, y recibió una dieta hipersódica (1.5%) y normosódica (0.25%) respectivamente. Se realizaron controles periódicos de natriuresis en 24 horas y filtración glomerular. Se utilizó la prueba estadística de Wilcoxon y de Friedman para evaluar los cambios de los resultados de cada grupo y las pruebas de U de Mann-Withney y de Kruskal Wallis, para evaluar los resultados entre los diferentes grupos. Los resultados mostraron que la dieta hiperprotéica de origen animal o vegetal incrementó la reserva funcional renal. Las de fuente de origen animal generaron un mayor incremento inicial en la natriuresis, en comparación a una de fuente de origen vegetal, que no incrementó la natriuresis. Sin embargo, un incremento sostenido de la reserva funcional renal o hiperfiltración asociado a la exposición de dieta hiperprotéica de origen animal o vegetal, no se asoció crónicamente a incrementos en la natriuresis. Luego de la sobrecarga sostenida de sal, la respuesta natriuretica estuvo conservada en los grupos sometidos previamente a dietas hiperprotéicas, y no hubo modificaciones a nivel de la filtración glomerular. La conclusión fue que una dieta hiperprotéica genera un incremento persistente en la reserva funcional renal asociado a un incremento agudo pero no crónico en la natriuresis; sin afectar la capacidad natriuretica luego de una sobrecarga de sal.

Introdução: A nefropatia crônica do enxerto permanece sendo a principal causa de perda tardia de enxertos renais. No momento, não existe uma estratégia terapêutica definida para minimizar ou reverter a perda da função renal. Diversas tentativas terapêuticas foram empregadas sem resultados definitivos. As estratégias de minimização de inibidores da calcineurina (CNI) com conversão para Micofenolato mofetil (MMF) e conversão para Sirolimo (SRL) são as mais promissoras. Este estudo avaliou a segurança e a eficácia dessas duas estratégias terapêuticas na progressão da nefropatia crônica do enxerto em pacientes transplantados renais. Métodos: Foram selecionados pacientes com filtração glomerular (RFG) medida por depuração de 51Cr-EDTA entre 25 e 60 ml/min/1,73 m2 que apresentaram alterações histológicas compatíveis com nefropatia crônica do enxerto e que não apresentaram proteinúria 24 h superior a 800 mg/24 h. Os pacientes foram randomizados para serem convertidos ao SRL ou manterem-se sob níveis baixos de CNI associados ao MMF e prednisona. O objetivo primário foi avaliar um objetivo composto pelos seguintes eventos: morte, perda do enxerto, rejeição aguda ou perda de RFG inicial superior a 20%. Os pacientes foram acompanhados por 12 meses e a uma análise por intenção de tratar foi realizada ao fim desse período. Resultados: Vinte e nove pacientes foram randomizados para os grupos SRL (n=14) e CNI (n=15). Não houve diferença entre os grupos quanto a os dados demográficos e imunológicos. Os valores de creatinina sérica e a TFG foram semelhantes no momento da randomização. A sobrevida dos pacientes e dos enxertos foi de 100%. Não foram observados episódios de rejeição aguda. Após 12 meses, não houve diferença significativa entre os grupos com relação à TFG. Houve maior número de eventos adversos não-graves no grupo SRL, destacandose, acne, edema, piora de dislipidemia e anemia. Entretanto, o número de eventos adversos graves não foi estatisticamente diferente entre os grupos. SRL foi descontinuado temporariamente em 1 paciente, mas não ocorreu descontinuação definitiva no estudo. Conclusão: Os dois esquemas terapêuticos apresentaram desempenhos rigorosamente semelhantes com relação à evolução da função renal e quanto à evolução histológica, mas houve um número maior de eventos adversos não-graves com o uso de sirolimo / Chronic allograft nephropathy is the main cause of late kidney graft loss. Several treatments have been proposed for this condition without conclusive results. Calcineurin inhibitors minimization and conversion to Sirolimus are the most promising alternatives. This study evaluated the safety and the efficacy of these therapeutic strategies on one-year progression of chronic allograft nephropathy in kidney transplant recipients. Patients with measured glomerular filtration rate (51Cr-EDTA plasmatic clearance) between 25 e 60 ml/min/1,73 m2 and histological findings of CAN, with proteinuria less than 800 mg/24 h were included. They were randomized either to Sirolimus or to low-level of CNI (both groups received MMF and prednisone). The primary end-point was a composite of first occurrence of death, graft loss, acute rejection or a 20% decrease of initial GFR. Patients were followed for 12 months and evaluated as intention-to-treat analysis. Twenty-nine patients were included in this study. Fourteen patients were randomized to SRL group and fifteen to CNI group. At baseline, no differences were detected in any of the demographic and immunologic group characteristics. Also, serum creatinine and GFR were not different at randomization. One year after conversion, patient and graft survival was 100%. At 12 months, there were no differences in GFR between two groups, in SRL group was 41,99 ± 13,48 ml/min/1,73 m2and in CNI group was 41,21 ± 9,10 ml/min/1,73 m2 (p=0,96). Non-serious adverse events, like anemia (p=0,006), acne (p=0,006), edema (p=0,005) and mouth ulcers (p=0,017) were more frequently found in the SRL group. No significant difference in serious adverse events was observed. SRL was temporarily interrupted in one patient. None of the patients dropped-out from the study and none required study drug discontinuation. In conclusion both regimens conferred equal beneficial in GFR preservation in CAN patients. However, SRL was associated with more adverse events

People of African ancestry (AA) are at greater risk of developing chronic kidney disease than those of non-AA. Much of this risk has been linked to specific genetic haplotypes on chromosome 22, near the genes APOL1, encoding apolipoprotein L1, and MYH9, encoding non-muscle myosin heavy chain IIA (NMHCIIA). The mechanisms by which the disease-associated chromosome 22 haplotypes promote kidney damage are unknown. Apolipoprotein L1 is a circulating protein with no known role in kidney function. However, the kidney disease-associated chromosome 22 haplotypes are protective against trypanosome infection, resulting in positive selective pressure for these haplotypes in western Africa, where trypanosome infection is endemic. In contrast, NMHCIIA may have an important role in glomerular function, and mutations in MYH9 are associated with glomerular disease, yet the disease-associated chromosome 22 haplotypes do not involve coding sequence variations in MYH9. With no clear disease-causing role for genes near the chromosome 22 risk locus, it is plausible that indirect mechanisms of gene regulation may be responsible for the increased disease risk. This study examines several potential pathways for kidney injury, including altered glomerular gene expression in carriers of chromosome 22 risk haplotypes, and the role of altered expression of MYH9 in podocyte cell biology and kidney disease. We found that carriers of chromosome 22 risk variants exhibited differential glomerular gene expression in pathways promoting kidney injury. We also found decreased glomerular NMHCIIA expression in human FSGS kidney biopsies, and altered cell structure and mechanical function when Myh9 is ablated in murine podocytes. Further, Myh9 podocyte deletion predisposed mice to glomerulopathy in response to injury by the DOCA-salt uninephrectomy model of hypertension. Taken together, these findings demonstrate direct and indirect effects of chromosome 22 risk variants on glomerular gene expression which promote kidney injury.

Wong Wai Lun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 119-125). / Abstract also in Chinese. / Acknowledgments --- p.i / Legend for Figures --- p.ii / Legend for Tables --- p.iv / Abstract --- p.v / Abstract in Chinese --- p.ix / Chapter Chapter I --- Introduction --- p.1 / Objective --- p.5 / Chapter Chapter II --- Literature Review / Chapter II.1. --- Anatomy of the urinary system --- p.6 / Chapter II.2. --- Physiology of the urinary system --- p.10 / Chapter II.3. --- Methods for investigating the urinary system --- p.12 / Chapter II.3.1. --- Plain film radiography --- p.12 / Chapter II.3.2. --- Excretory Urogram --- p.12 / Chapter II.3.3. --- Ultrasound --- p.13 / Chapter II.3.4. --- Computed Tomography --- p.15 / Chapter II.3.5. --- Renal Angiography --- p.16 / Chapter II.3.6. --- Magnetic Resonance Imaging (MRI) --- p.16 / Chapter II.3.7. --- Radionuclide Imaging --- p.17 / Chapter II.4. --- Radiopharmaceuticals for renal parenchyma imaging --- p.17 / Chapter II.4.1. --- Tc-99m GHA --- p.18 / Chapter II.4.1.1. --- Chemistry of Tc-99m GHA --- p.18 / Chapter II.4.1.2. --- Preparation --- p.18 / Chapter II.4.1.3. --- Doses --- p.18 / Chapter II.4.1.4. --- Biological behavior --- p.19 / Chapter II.4.2. --- Tc-99m DMSA / Chapter II.4.2.1. --- Chemistry of Technetium-99m Dimercaptosuccinic Acid (Tc-99m DMSA) --- p.20 / Chapter II.4.2.2. --- Chemical property of Tc-99m DMSA --- p.21 / Chapter II.4.2.3. --- Preparation --- p.22 / Chapter II.4.2.4. --- Radiochemical purity measurement --- p.22 / Chapter II.4.2.5. --- Doses --- p.23 / Chapter II.4.2.6. --- Pharmacokinetic of Tc-99m DMSA --- p.23 / Chapter II.4.2.7. --- Renal handling of injected Tc-99m DMSA --- p.25 / Chapter II.5. --- General consideration for quantitative uptake measurement in organs --- p.26 / Chapter II.5.1. --- Clinical significance of renal Tc-99m DMSA uptake --- p.28 / Chapter II.5.2. --- Special consideration and problems for quantitative renal Tc-99m uptake measurement --- p.29 / Chapter II.5.3. --- Suggestions and solutions for quantitative renal Tc-99m uptake measurement --- p.29 / Chapter II.5.3.1. --- Planar images Vs SPECT images for quantification --- p.29 / Chapter II.5.3.2. --- Background subtraction --- p.31 / Chapter II.5.3.3. --- Choice of location for background ROI --- p.32 / Chapter II.5.3.4. --- Attenuation --- p.35 / Chapter II.5.3.5. --- Principle of the conjugate view method --- p.36 / Chapter II.5.3.6. --- Body thickness and kidney depth measurement --- p.37 / Chapter II.6. --- Glomerular Filtration / Chapter II.6.1. --- Introduction --- p.39 / Chapter II.6.2. --- Gold standard for GFR measurement --- p.40 / Chapter II.6.3. --- Laboratory studies for the measurement of glomerular filtration : Serum Creatinine and Blood Urea Nitrogen (BUN) levels --- p.41 / Chapter II.6.3.1. --- Calculation of Creatinine Clearance Rate --- p.43 / Chapter II.6.3.2. --- Critique for using creatinine clearance as a measurement of renal function --- p.44 / Chapter II.6.3.3. --- Limitation of the serum creatinine concentration used alone as a measurement of renal function --- p.46 / Chapter II.6.4. --- Radionuclide technique for the assessment of the glomerular function --- p.48 / Chapter II.6.4.1. --- Diethylene Triamine Penta Acetic acid (DTPA) --- p.49 / Chapter II.6.4.2. --- Methods / Chapter II.6.4.2.1. --- Measurement of Glomerular Filtration Rate using Tc-99m DTPA with single injection techniques --- p.51 / Chapter II.6.4.2.2. --- Compartment model --- p.52 / Chapter II.6.4.2.2a. --- Two-compartment model --- p.52 / Chapter II.6.4.2.2b. --- Single-compartment model --- p.54 / Chapter II.6.4.2.3. --- Single blood sample technique: a modification of Tauxe's OIH method in which counts in a single plasma sample correlated with a GFR nomogram --- p.56 / Chapter II.6.4.2.4. --- Gamma camera based method --- p.58 / Chapter II.6.4.2.4a. --- Gates-modification of Schlegel's OIH technique --- p.58 / Chapter II.6.4.2.4b. --- Critique for the Gamma camera technique for measuring GFR --- p.62 / Chapter II.7. --- The relationship between the Tc-99m DMSA uptake and GFR --- p.67 / Chapter Chapter III --- Material and Methods --- p.69 / Chapter III.1. --- Subjects and Sampling Methods --- p.69 / Chapter III.2. --- Quantitation of Absolute DMSA uptake --- p.70 / Chapter III.2.1. --- Parameters for Tc-99m DMSA uptake study --- p.70 / Chapter III.2.1.1. --- Materials and methods --- p.70 / Chapter III.2.1.1.1. --- Instrumentation --- p.70 / Chapter III.2.1.1.2. --- Dosage --- p.70 / Chapter III.2.1.1.3. --- Optimum acquisition start time --- p.70 / Chapter III.2.1.1.4. --- Length of acquisition time --- p.71 / Chapter III.2.1.1.5. --- Acquisition parameter --- p.71 / Chapter III.3. --- Calculation of absolute renal DMSA uptake --- p.72 / Chapter III.3.1. --- Attenuation Coefficient factor(μ) --- p.73 / Chapter III.3.2. --- Table attenuation --- p.75 / Chapter III.3.3. --- Body thickness measurement --- p.77 / Chapter III.3.4. --- Decay correction --- p.78 / Chapter III.3.5. --- Calculation of DMSA uptake --- p.78 / Chapter III.3.6. --- Counting dose injected --- p.80 / Chapter III.3.7. --- Calculation of absolute quantitation of Tc-99m DMSA uptake --- p.80 / Chapter III.3.8. --- Dose infiltration --- p.81 / Chapter III.4. --- GFR measurement --- p.82 / Chapter III.4.1. --- Instrumentation --- p.82 / Chapter III.4.2. --- Methods --- p.82 / Chapter III.5. --- Statistical and analytical methods --- p.84 / Chapter Chapter IV --- Results --- p.87 / Chapter IV. 1. --- Characteristics of experimental subjects and their serum creatinine profile --- p.88 / Chapter IV.2. --- Absolute Tc-99m DMSA uptake / Chapter IV.2.1. --- The change of absolute Tc-99m uptake with time --- p.89 / Chapter IV.2.2. --- Absolute Tc-99m DMSA uptake measurement at 6 and 24 hours --- p.90 / Chapter IV.2.3. --- Gender difference in absolute Tc-99m uptake measurement at 6 hour --- p.92 / Chapter IV.3. --- GFR measurement --- p.93 / Chapter IV.3.1. --- GFR measurement by single (3hr) and double (1&3 hrs) plasma sampling --- p.93 / Chapter IV.3.2. --- Gender difference in GFR measurement using single plasma sampling --- p.96 / Chapter IV.4. --- Univariate Correlation --- p.97 / Chapter IV.4.1. --- Correlation between GFR using single plasma sampling and absolute Tc-99m uptake --- p.97 / Chapter IV.4.2. --- Correlation between GFR using single plasma sampling and plasma creatinine levels --- p.98 / Chapter IV.4.3. --- Correlation between anthropometric variables on GFR(3 hr) --- p.99 / Chapter IV.4.4. --- Correlation between anthropometric variables and serum creatinine plasma level on absolute Tc-99m DMSA uptake measurement at 6 hour --- p.101 / Chapter IV.4.5. --- Multiple linear stepwise regression --- p.103 / Chapter Chapter V. --- Discussion / Chapter V. 1 --- . Review of the study --- p.104 / Chapter V.1.1. --- Experimental subjects and their absolute Tc-99m DMSA uptake (%) at 6 hr --- p.104 / Chapter V.1.2. --- Experimental subjects and their GFR(3 hr) --- p.105 / Chapter V.2. --- Discussion on subject --- p.105 / Chapter V.2.1. --- Subject preparation --- p.106 / Chapter V.3. --- Discussion of method --- p.106 / Chapter V.3.1. --- Equipment --- p.106 / Chapter (a) --- Dose calibrator --- p.106 / Chapter (b) --- The sensitivity of the head 1 and 2 of the gamma camera --- p.106 / Chapter (c) --- Validation of quantification of injected activity by gamma camera method--------constancy of performance for gamma camera --- p.110 / Chapter (d) --- LEHR Collimator --- p.112 / Chapter (f) --- Dead time loss --- p.112 / Chapter V.4. --- Discussion on measurement --- p.113 / Chapter (a) --- Length of acquisition time --- p.113 / Chapter (b) --- Attenuation Coefficient factor (\x) --- p.113 / Chapter (c) --- "Body thickness, L, measurement" --- p.113 / Chapter (d) --- Optimum acquisition time for data collection --- p.115 / Chapter v.5. --- Discussion on overall error estimation --- p.115 / Chapter (a) --- Tc-99m DMSA uptake measurement at 6 hr --- p.115 / Chapter (b) --- GFR measurement by single (3 hr) sample --- p.116 / Chapter Chapter VI --- Conclusion --- p.117 / Reference --- p.119 / Appendix I --- p.126 / Appendix II --- p.128 / Appendix III --- p.134

Objetivo: O objetivo do presente estudo foi avaliar o impacto da doença periodontal sobre a função renal em pacientes pré–dialíticos nos estágios 3, 4 e 5 da doença renal crônica (DRC). Metodologia: Dados demográficos, socioeconômicos e de história médica de 139 pacientes do Serviço Nefrologia do Hospital de Clínicas de Porto Alegre (HCPA) foram obtidos por meio de entrevista e análise de prontuário. Exames clínicos periodontais completos foram realizados por examinadores treinados e calibrados. Foram realizadas associações entre a condição periodontal e os diferentes estágios da DRC e com a taxa de filtração glomerular (TFG). Resultados: Ter periodontite grave aumentou em, aproximadamente, 2,8 e 3,4 vezes a chance de estar nos estágios 4 e 5 da DRC quando comparado a estar no estágio 3 (referência), respectivamente (p<0,05). Além disso, ter dois ou mais dentes com perda de inserção maior ou igual a 6mm aumentou em 3,9 vezes a chance de estar no estágio 5 da DRC (p<0,05). Com relação à TFG, tanto o fato de ter periodontite grave quanto o de apresentar dois ou mais dentes com perda de inserção maior ou igual a 6mm estiveram significativamente associados a uma menor taxa de filtração glomerular (p=0,02 e p=0,01, respectivamente). Conclusão: A doença periodontal aumenta a chance de piores desfechos renais em pacientes com DRC pré-dialiticos, mesmo quando ajustado para importantes confundidores. / Aims: The aim of the present study was to evaluate the impact of periodontal disease on renal function in pre-dialytic patients in stages 3, 4 and 5 of chronic kidney disease (CKD). Materials and Methods: Demographic, socioeconomic and medical history data of 139 patients from the Nephrology Service at the Hospital de Clínicas de Porto Alegre (HCPA) were obtained through interview and clinical records. Complete periodontal clinical examinations were performed by trained and calibrated examiners. Associations between the periodontal condition and different stages of CKD, as well as with the glomerular filtration rate (GFR) were evaluated. Results: Severe periodontitis increased by 2.8 and 3.4 times the chance of being in stages 4 and 5 of CKD when compared to the reference (stage 3), respectively (p <0.05). In addition, having two or more teeth with clinical attachment loss ≥6mm increased by 3.9 times the probability of being in stage 5 of the CKD (p <0.05). Regarding GFR, severe periodontitis and having two or more teeth with clinical attachment loss ≥6mm were significantly associated with a lower glomerular filtration rate (p = 0.02 and p = 0.01, respectively). Conclusion: Periodontal disease increases the chance of worse renal outcomes in patients with pre-dialytic CKD, even when adjusted for major confounders.

Midline convergence of organ primordia is an important mechanism for shaping the vertebrate body-plan at various stages of development, such as the morphogenesis of the heart and endoderm. Down regulation of wnt or noncanonical wnt signalling components, such as dishelleved (Dvl) or RhoA GTPase (RhoA), impairs midline convergence of the heart primordia and endoderm in zebrafish. This suggests that wnt signaling plays an important role in regulating midline convergence. At the early patterning stage of the zebrafish kidney, the two pronephric-glomerular primodia (PGP), which derive from intermediate mesoderm, converge towards the midline and fuse to form a functional pronephros. In contrast, during development of the mammalian kidney, the pronephros degenerates as the mesonephros develops without midline convergence. The hypothesis is thus that there is/are mechanisms underlying midline convergence of PGP in zebrafish, which is/are in addition to the control of the non-canonical wnt/Dvl/RhoA pathway and specific to kidney morphogenesis. In this study, the aim was to identify genetic factors that are specifically involved in the mechanism of PGP midline convergence by establishing a cell lineage tracing transgenic system with Cre-loxP, followed by the analysis of selected mutant embryos using the cell lineage tracing system, whole-mount in situ hybridization (WISH) and immunostaining. The cell lineage tracing system was generated, and tested. Constructs, in which β-actin promoter drives the transcription of the reporter genes, were microinjected into zebrafish embryos at 1- to 4-cell stages. The mRNAs in microinjected embryos (5 dpf) were analyzed by RT-PCR. The results show that the constructs induced indiscriminate alternative splicing. RNA splicing mechanisms were not affected by transcription termination when the polyA signal was located in introns. To provide an alternative approach, three mutants were selected after screening of available ENU zebrafish mutants. These mutants were chosen not only because of their genetic importance in cell adhesion and motility but also because of their respective developmental defects in tissues surrounding the PGP, such as the notochord (no tail, ntl), somite (spadetail, spt), and endodermal tissues (zygotic oneeyed pinhead, Zoep). Spt and ntl are key targets of fibroblast growth factor (FGF) signalling in the trunk and tail respectively. EGP-CFC gene oep is a Nodal signalling cofactor. Firstly, a rapid genotyping technique was developed, which was applied in identifying the mutant alleles. Since the tools for tracing PGP using transgenes were unavailable, the three mutants were analyzed by WISH and immunostaining. Zygotic mutation of Zoep causes a PGP midline convergence phenotype of variable severity due to maternal Oep effects. In more than 90% of Zoep-/- embryos, PGP midline convergence was impaired. Even though the abnormality could be observed as early as 15 hpf, the differentiation of the PGP was not affected. Heart primordial phenotypes were also observed but they did not correlate with that of the PGP phenotypes. Embryos homozygous for mutations in T-box transcription factors, ntl or spt had normal heart midline convergence phenotypes. PGP midline convergence abnormality was observed in spt-/- but not in ntl-/- prior to 36 hpf. In addition the extracellular matrix (ECM) might play a key role in the mechanisms of PGP midline convergence. Furthermore, PGP midline convergence proceeds from 10 hpf (the specification of intermediate mesoderm) to 48 hpf (fused pronephric glomerulus) in wild type zebrafish embryos. The process was quantified by 2D image analysis of the PGP distance. Prior to 18 hpf, PGP midline convergence is closely correlated with the midline convergence of mesoderm but not at later stages in Zoep-/-. Spt is essential for PGP but not for cardiac primordium midline convergence. Data from this research suggests that there is not one universal mechanism, which controls all the midline convergence of organ primordia. Indeed, specific factors, which depend on tissues and development stages, are also required.

Publicación a texto completo no autorizada por el autor / En los últimos años se ha demostrado que la enfermedad renal crónica y la cardiopatía isquémica tienen diversos factores de riesgo y mecanismos de progresión en común. La determinación de cistatina C, un inhibidor de las cisteín-proteasas, está adquiriendo importancia como marcador de la función renal y como predictor del riesgo cardiovascular, sin embargo no se han encontrado estudios en la población peruana sobre la relación de estas variables. El objetivo de esta investigación es la de analizar los niveles de cistatina C y su relación con la función renal y el perfil de riesgo coronario en pacientes del Hospital Nacional Guillermo Almenara Irigoyen, EsSalud. Se realizó un estudio cuantitativo analítico, observacional de tipo transversal. Se tuvo como muestra para el modelo predictor la prevalencia estimada para insuficiencia renal de 3% con un error alfa de 0.05 y precisión deseada 0.05, resultó en un tamaño de muestra de 377. Los sujetos fueron seleccionados a través de muestreo aleatorio estratificado. Para la comparación de valores medios de variables paramétricas se aplicó la prueba t para muestras independientes. Para la comparación de medianas de variables no paramétricas se empleó Mann-Whitney. Para comparar proporciones utilizamos la prueba de chi-cuadrado. Se utilizó regresión múltiple para la identificación la relación entre las variables. Se realizó un modelo de análisis multivariante para confirmar la persistencia de la relación función renal y el perfil de riesgo coronario con los niveles de cistatina C ajustado a género y edad. Se consideró un nivel de significancia de p<.05. Los resultados fueron de 187 (48%) pacientes presentaron Cistatina C elevada (ajustada por edad). Se encontró correlación gradual y significativa entre los niveles elevados de cistatina C, el perfil renal (creatinina: p<0.001, úrea: p=0.002) y los componentes cLDL (p=0.021) y cVLDL (p=0.002) del perfil de riesgo coronario. Los resultados muestran que las variables creatinina, úrea, cLDL y el cVLDL están relacionadas significativamente con cistatina C y explican las variaciones en la concentración y los niveles elevados de esta proteína. / Tesis

C3 glomerulopathy (C3G) encompasses a group of severe renal diseases characterized by “dominant C3” deposition in the renal glomerulus. Patients typically present as nephritic nephrotics, with hematuria, hypertension, heavy proteinuria and edema. Within ten years of diagnosis, 50% of affected patients progress to end-stage renal disease and require dialysis or renal transplantation. No treatment is available to halt disease progression and thus both disease recurrence and allograft loss are common after transplantation. Genetic studies of C3G have firmly implicated dysregulation of the alternative pathway (AP) of complement in disease pathogenesis. In addition to genetic factors, acquired factors like autoantibodies can also exaggerate AP activity in the circulation to cause C3G. Although AP dysregulation in the circulation (i.e. fluid-phase dysregulation) has been well studied in these patients, AP activity in the glomerular microenvironment is not well understood. In this body of work, we used MaxGel, an ex-vivo surrogate for the glomerular extracellular matrix, to study AP activity and regulation. We showed that C3 convertase can be assembled on MaxGel and elucidated the dynamics of its formation and decay in the presence of complement regulators. We confirm that on MaxGel factor H (fH) inhibits C3 convertase formation and accelerates its decay, while properdin has a stabilizing effect. We also show that the complement factor H-related proteins (FHRs) are vital to the regulation of AP activity. Consistent with our MaxGel data, CFHR gene-fusion events have been reported as genetic drivers of disease in a few familial cases of C3G. One such familial case in which we identified and characterized the rearrangement event results from a novel CFHR5-CFHR2 fusion gene. The fusion gene is translated into a circulating FHR-5/-2 protein that consists of the first two SCRs of FHR-5 followed by all four SCRs of FHR-2. The structural repetition of SCR1-2 followed by another SCR1-2 motif facilitates the formation of complex FHR-1, FHR-2 and FHR-5 multimers, which have enhanced affinity for C3b and by out-competing fH, lead to impaired C3 convertase regulation in the glomerular microenvironment. Finally, we tested gene therapy as a tool to rescue the disease phenotype and restore fluid-phase AP complement control in a mouse model of C3G (Cfh-/-/huCR1-Tg mice). Using the piggyBac transposon system, we introduced a construct derived from complement regulator 1 (CR1) into Cfh-/-/huCR1-Tg mice. Delivery of sCR1-AC via hydrodynamic tail vein injection provided constitutive circulatory expression of sCR1-AC, and in animals followed for 6 months, we found that long-term expression of this complement regulator rescued the renal phenotype. These results suggest that sCR1 may be a potential therapy for patients with this disease.