1000 resultados para Función renal
Resumo:
We examined the effect of exercise training (Ex) without (Ex 0%) or with a 3% workload (Ex 3%) on different cardiac and renal parameters in renovascular hypertensive (2K1C) male Fisher rats weighing 150-200 g. Ex was performed for 5 weeks, 1 h/day, 5 days/week. Ex 0% or Ex 3% induced similar attenuation of baseline mean arterial pressure (MAP, 119 ± 5 mmHg in 2K1C Ex 0%, N = 6, and 118 ± 5 mmHg in 2K1C Ex 3%, N = 11, vs 99 ± 4 mmHg in sham sedentary (Sham Sed) controls, N = 10) and heart rate (HR, bpm) (383 ± 13 in 2K1C Ex 0%, N = 6, and 390 ± 14 in 2K1C Ex 3%, N = 11 vs 371 ± 11 in Sham Sed, N = 10,). Ex 0%, but not Ex 3%, improved baroreflex bradycardia (0.26 ± 0.06 ms/mmHg, N = 6, vs 0.09 ± 0.03 ms/mmHg in 2K1C Sed, N = 11). Morphometric evaluation suggested concentric left ventricle hypertrophy in sedentary 2K1C rats. Ex 0% prevented concentric cardiac hypertrophy, increased cardiomyocyte diameter and decreased cardiac vasculature thickness in 2K1C rats. In contrast, in 2K1C, Ex 3% reduced the concentric remodeling and prevented the increase in cardiac vasculature wall thickness, decreased the cardiomyocyte diameter and increased collagen deposition. Renal morphometric analysis showed that Ex 3% induced an increase in vasculature wall thickness and collagen deposition in the left kidney of 2K1C rats. These data suggest that Ex 0% has more beneficial effects than Ex 3% in renovascular hypertensive rats.
Resumo:
Animal models of gentamicin nephrotoxicity present acute tubular necrosis associated with inflammation, which can contribute to intensify the renal damage. Hydrogen sulfide (H2S) is a signaling molecule involved in inflammation. We evaluated the effect of DL-propargylglycine (PAG), an inhibitor of endogenous H2S formation, on the renal damage induced by gentamicin. Male Wistar rats (N = 8) were injected with 40 mg/kg gentamicin (im) twice a day for 9 days, some of them also received PAG (N = 8, 10 mg·kg-1·day-1, ip). Control rats (N = 6) were treated with saline or PAG only (N = 4). Twenty-four-hour urine samples were collected one day after the end of these treatments, blood samples were collected, the animals were sacrificed, and the kidneys were removed for quantification of H2S formation and histological and immunohistochemical studies. Gentamicin-treated rats presented higher sodium and potassium fractional excretion, increased plasma creatinine [4.06 (3.00; 5.87) mg%] and urea levels, a greater number of macrophages/monocytes, and a higher score for tubular interstitial lesions [3.50 (3.00; 4.00)] in the renal cortex. These changes were associated with increased H2S formation in the kidneys from gentamicin-treated rats (230.60 ± 38.62 µg·mg protein-1·h-1) compared to control (21.12 ± 1.63) and PAG (11.44 ± 3.08). Treatment with PAG reduced this increase (171.60 ± 18.34), the disturbances in plasma creatinine levels [2.20 (1.92; 4.60) mg%], macrophage infiltration, and score for tubular interstitial lesions [2.00 (2.00; 3.00)]. However, PAG did not interfere with the increase in fractional sodium excretion provoked by gentamicin. The protective effect of PAG on gentamicin nephrotoxicity was related, at least in part, to decreased H2S formation.
Resumo:
The objective of this study was to investigate renal function in a cohort of 98 patients with sickle cell disease (SCD) followed up at a tertiary hospital in Brazil. Clinical and laboratory characteristics at the time of the most recent medical examination were analyzed. Renal function was evaluated by the estimation of glomerular filtration rate (GFR) by the criteria of the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI). We compared patients with normal GFR to patients with decreased GFR (<60 mL·min-1·(1.73 m²)-1) and hyperfiltration (>120 mL·min-1·(1.73 m²)-1). Comparison between patients according to the use of hydroxyurea and comparison of clinical and laboratory parameters according to GFR were also carried out. Average patient age was 33.8 ± 13.3 years (range 19-67 years), and 57 (58.1%) patients were females. The comparison of patients according to GFR showed that patients with decreased GFR (<60 mL·min-1·(1.73 m²)-1) were older, had lower levels of hematocrit, hemoglobin and platelets and higher levels of urea and creatinine. Independent risk factors for decreased GFR were advanced age (OR = 21.6, P < 0.0001) and anemia (OR = 39.6, P < 0.0001). Patients with glomerular hyperfiltration tended to be younger, had higher levels of hematocrit, hemoglobin and platelets and lower levels of urea and creatinine, with less frequent urinary abnormalities. Hydroxyurea, at the dosage of 500-1000 mg/day, was being administered to 28.5% of the patients, and there was no significant difference regarding renal function between the two groups. Further studies are required to establish the best therapeutic approach to renal abnormalities in SCD.
Resumo:
Circulating microRNAs (miRNAs) may represent a potential noninvasive molecular biomarker for various pathological conditions. Moreover, the detection of circulating miRNAs can provide important novel disease-related information. In particular, inflammation-associated miR-155 and endothelial-enriched miR-126 are reported to be associated with vascular homeostasis. Vascular damage is a common event described in end-stage renal disease (ESRD). We hypothesized that miR-155 and miR-126 may be detectable in the circulation and serve as potential biomarkers for risk stratification. In this study, we assessed miR-155 and miR-126 in the plasma of 30 ESRD patients and 20 healthy controls using real-time quantification RT-PCR. The circulating levels of miR-155 and miR-126 were significantly reduced in patients with ESRD compared to healthy controls. However, there was no significant difference of circulating miR-155 and miR-126 levels between prehemodialysis and posthemodialysis patients. Furthermore, both circulating miR-126 and miR-155 correlated positively with estimated glomerular filtration rate (miR-126: r = 0.383, P = 0.037; miR-155: r = 0.494, P = 0.006) and hemoglobin (miR-126: r = 0.515, P = 0.004; miR-155: r = 0.598, P < 0.001) and correlated inversely with phosphate level (miR-126: r = -0.675, P < 0.001; miR-155: r = -0.399, P = 0.029). Pearson’s correlation was used to compare circulating levels of miRNAs with clinical parameters. These results suggested that circulating miR-155 and miR-126 might be involved in the development of ESRD. Further studies are needed to demonstrate the role of circulating miR-155 and miR-126 as candidate biomarkers for risk estimation.
Resumo:
The maintenance of extracellular Na+ and Cl- concentrations in mammals depends, at least in part, on renal function. It has been shown that neural and endocrine mechanisms regulate extracellular fluid volume and transport of electrolytes along nephrons. Studies of sex hormones and renal nerves suggested that sex hormones modulate renal function, although this relationship is not well understood in the kidney. To better understand the role of these hormones on the effects that renal nerves have on Na+ and Cl- reabsorption, we studied the effects of renal denervation and oophorectomy in female rats. Oophorectomized (OVX) rats received 17β-estradiol benzoate (OVE, 2.0 mg·kg-1·day-1, sc) and progesterone (OVP, 1.7 mg·kg-1·day-1,sc). We assessed Na+ and Cl-fractional excretion (FENa+ and FECl-, respectively) and renal and plasma catecholamine release concentrations. FENa+, FECl-, water intake, urinary flow, and renal and plasma catecholamine release levels increased in OVX vs control rats. These effects were reversed by 17β-estradiol benzoate but not by progesterone. Renal denervation did not alter FENa+, FECl-, water intake, or urinary flow values vs controls. However, the renal catecholamine release level was decreased in the OVP (236.6±36.1 ng/g) and denervated rat groups (D: 102.1±15.7; ODE: 108.7±23.2; ODP: 101.1±22.1 ng/g). Furthermore, combining OVX + D (OD: 111.9±25.4) decreased renal catecholamine release levels compared to either treatment alone. OVE normalized and OVP reduced renal catecholamine release levels, and the effects on plasma catecholamine release levels were reversed by ODE and ODP replacement in OD. These data suggest that progesterone may influence catecholamine release levels by renal innervation and that there are complex interactions among renal nerves, estrogen, and progesterone in the modulation of renal function.
Resumo:
Glycosaminoglycans (GAGs) participate in a variety of processes in the kidney, and evidence suggests that gender-related hormones participate in renal function. The aim of this study was to analyze the relationship of GAGs, gender, and proteinuria in male and female rats with chronic renal failure (CRF). GAGs were analyzed in total kidney tissue and 24-h urine of castrated (c), male (M), and female (F) Wistar control (C) rats (CM, CMc, CF, CFc) and after 30 days of CRF induced by 5/6 nephrectomy (CRFM, CRFMc, CRFF, CRFFc). Total GAG quantification and composition were determined using agarose and polyacrylamide gel electrophoresis, respectively. Renal GAGs were higher in CF compared to CM. CRFM presented an increase in renal GAGs, heparan sulfate (HS), and proteinuria, while castration reduced these parameters. However, CRFF and CRFFc groups showed a decrease in renal GAGs concomitant with an increase in proteinuria. Our results suggest that, in CRFM, sex hormones quantitatively alter GAGs, mainly HS, and possibly the glomerular filtration barrier, leading to proteinuria. The lack of this response in CRFMc, where HS did not increase, corroborates this theory. This pattern was not observed in females. Further studies of CRF are needed to clarify gender-dependent differences in HS synthesis.
Resumo:
Interest in the role of extracellular vesicles in various diseases including cancer has been increasing. Extracellular vesicles include microvesicles, exosomes, apoptotic bodies, and argosomes, and are classified by size, content, synthesis, and function. Currently, the best characterized are exosomes and microvesicles. Exosomes are small vesicles (40-100 nm) involved in intercellular communication regardless of the distance between them. They are found in various biological fluids such as plasma, serum, and breast milk, and are formed from multivesicular bodies through the inward budding of the endosome membrane. Microvesicles are 100-1000 nm vesicles released from the cell by the outward budding of the plasma membrane. The therapeutic potential of extracellular vesicles is very broad, with applications including a route of drug delivery and as biomarkers for diagnosis. Extracellular vesicles extracted from stem cells may be used for treatment of many diseases including kidney diseases. This review highlights mechanisms of synthesis and function, and the potential uses of well-characterized extracellular vesicles, mainly exosomes, with a special focus on renal functions and diseases.
Resumo:
Although radical nephrectomy alone is widely accepted as the standard of care in localized treatment for renal cell carcinoma (RCC), it is not sufficient for the treatment of metastatic RCC (mRCC), which invariably leads to an unfavorable outcome despite the use of multiple therapies. Currently, sequential targeted agents are recommended for the management of mRCC, but the optimal drug sequence is still debated. This case was a 57-year-old man with clear-cell mRCC who received multiple therapies following his first operation in 2003 and has survived for over 10 years with a satisfactory quality of life. The treatments given included several surgeries, immunotherapy, and sequentially administered sorafenib, sunitinib, and everolimus regimens. In the course of mRCC treatment, well-planned surgeries, effective sequential targeted therapies and close follow-up are all of great importance for optimal management and a satisfactory outcome.
Resumo:
Exercise training (Ex) has been recommended for its beneficial effects in hypertensive states. The present study evaluated the time-course effects of Ex without workload on mean arterial pressure (MAP), reflex bradycardia, cardiac and renal histology, and oxidative stress in two-kidney, one-clip (2K1C) hypertensive rats. Male Fischer rats (10 weeks old; 150–180 g) underwent surgery (2K1C or SHAM) and were subsequently divided into a sedentary (SED) group and Ex group (swimming 1 h/day, 5 days/week for 2, 4, 6, 8, or 10 weeks). Until week 4, Ex decreased MAP, increased reflex bradycardia, prevented concentric hypertrophy, reduced collagen deposition in the myocardium and kidneys, decreased the level of thiobarbituric acid-reactive substances (TBARS) in the left ventricle, and increased the catalase (CAT) activity in the left ventricle and both kidneys. From week 6 to week 10, however, MAP and reflex bradycardia in 2K1C Ex rats became similar to those in 2K1C SED rats. Ex effectively reduced heart rate and prevented collagen deposition in the heart and both kidneys up to week 10, and restored the level of TBARS in the left ventricle and clipped kidney and the CAT activity in both kidneys until week 8. Ex without workload for 10 weeks in 2K1C rats provided distinct beneficial effects. The early effects of Ex on cardiovascular function included reversing MAP and reflex bradycardia. The later effects of Ex included preventing structural alterations in the heart and kidney by decreasing oxidative stress and reducing injuries in these organs during hypertension.
Resumo:
HIV infection has a broad spectrum of renal manifestations. This study examined the clinical and histological manifestations of HIV-associated renal disease, and predictors of renal outcomes. Sixty-one (64% male, mean age 45 years) HIV patients were retrospectively evaluated. Clinical presentation and renal histopathology were assessed, as well as CD4 T-cell count and viral load. The predictive value of histological lesion, baseline CD4 cell count and viral load for end-stage renal disease (ESRD) or death were determined using the Cox regression model. The outcomes of chronic kidney disease (CKD) and ESRD or death were evaluated by baseline CD4 cell count. The percent distribution at initial clinical presentation was non-nephrotic proteinuria (54%), acute kidney injury (28%), nephrotic syndrome (23%), and chronic kidney disease (22%). Focal segmental glomerulosclerosis (28%), mainly the collapsing form (HIVAN), acute interstitial nephritis (AIN) (26%), and immune complex-mediated glomerulonephritis (ICGN) (25%) were the predominant renal histology. Baseline CD4 cell count ≥200 cells/mm3 was a protective factor against CKD (hazard ratio=0.997; 95%CI=0.994-0.999; P=0.012). At last follow-up, 64% of patients with baseline CD4 ≥200 cells/mm3 had eGFR >60 mL·min-1·(1.73 m2)-1 compared to the other 35% of patients who presented with CD4 <200 cells/mm3 (log rank=9.043, P=0.003). In conclusion, the main histological lesion of HIV-associated renal disease was HIVAN, followed by AIN and ICGN. These findings reinforce the need to biopsy HIV patients with kidney impairment and/or proteinuria. Baseline CD4 cell count ≥200 cells/mm3 was associated with better renal function after 2 years of follow-up.
Resumo:
The Banff classification was introduced to achieve uniformity in the assessment of renal allograft biopsies. The primary aim of this study was to evaluate the impact of specimen adequacy on the Banff classification. All renal allograft biopsies obtained between July 2010 and June 2012 for suspicion of acute rejection were included. Pre-biopsy clinical data on suspected diagnosis and time from renal transplantation were provided to a nephropathologist who was blinded to the original pathological report. Second pathological readings were compared with the original to assess agreement stratified by specimen adequacy. Cohen's kappa test and Fisher's exact test were used for statistical analyses. Forty-nine specimens were reviewed. Among these specimens, 81.6% were classified as adequate, 6.12% as minimal, and 12.24% as unsatisfactory. The agreement analysis among the first and second readings revealed a kappa value of 0.97. Full agreement between readings was found in 75% of the adequate specimens, 66.7 and 50% for minimal and unsatisfactory specimens, respectively. There was no agreement between readings in 5% of the adequate specimens and 16.7% of the unsatisfactory specimens. For the entire sample full agreement was found in 71.4%, partial agreement in 20.4% and no agreement in 8.2% of the specimens. Statistical analysis using Fisher's exact test yielded a P value above 0.25 showing that - probably due to small sample size - the results were not statistically significant. Specimen adequacy may be a determinant of a diagnostic agreement in renal allograft specimen assessment. While additional studies including larger case numbers are required to further delineate the impact of specimen adequacy on the reliability of histopathological assessments, specimen quality must be considered during clinical decision making while dealing with biopsy reports based on minimal or unsatisfactory specimens.
Resumo:
En este trabajo se determinó la vida útil de una fórmula dietética para niños con síndrome diarréico, empleando la disminución de lisina disponible como indicador de deterioro. Muestras del producto fueron empacadas en envases de material multilaminado (papel-plástico-aluminio) y almacenadas a 25, 30 y 35°C, por dos meses. La lisina disponible fue medida con una frecuencia semanal y los datos fueron analizados para determinar la cinética de la reacción de deterioro y su relación con la temperatura. Al finalizar el estudio, la cantidad de lisina disponible remanente fue de 38,5% (a 25°C); 15,3 % (a 30°C) y 14,1% (a 35°C). La cinética de la reacción de deterioro fue de orden uno, dependiente de la temperatura de almacenamiento, según la ecuación de interrelación de Arrhenius, con un valor de energía de activación de 15,17 kcal/mol, por lo que cae dentro del rango de las reacciones de oxidación de lípidos. De acuerdo a las características del producto [contenido de lípidos (17,5%), proteínas (17,3%) y una actividad de agua de 0,46], la disminución de lisina pudiera ser explicada por la interacción de productos de oxidación de lípidos con proteínas. Considerando un valor de 0,422g lis/100g producto como punto crítico, se predijo la vida útil del producto a temperaturas diferentes a las evaluadas. Condiciones de almacenamiento por debajo de 30°C, garantizan un mayor período de vida útil: hasta 9 meses a 15°C, 6 meses a 20°C y 3 meses a 28°C, en función del indicador de deterioro evaluado.
Resumo:
El conocimiento de las propiedades viscoelásticas de los alimentos es muy útil en el diseño y predicción de la estabilidad de muestras almacenadas. El trabajo tuvo como objetivos caracterizar las propiedades viscoelásticas de las muestras de pulpa de membrillo a diferentes concentraciones de sólidos solubles. El estudio reológico del pulpa de membrillo fue realizado en el rango de concentraciones de 12,3 a 28°Brix a la temperatura de 20°C. Las medidas viscoelásticas fueron realizadas con un reômetro Haake Rheostress RS100 y fue seleccionado el barrido de frecuencia entre 0,1 a 100 Hz. Los resultados demostraron que para la muestra de 28°Brix la pulpa se comportó como un semi-sólido en todo el rango de frecuencia estudiada. Para la concentración de 24°Brix, a bajas frecuencias, la pulpa se comportó como un semi-líquido (G">G') mientras que en frecuencias más altas se comportó como semi-sólido (G'>G"). Para la pulpa de 16 e 20°Brix hubo el predominio del carácter viscoso sobre el carácter elástico. Para la pulpa de 12,3°Brix no fue posible determinar los valores G' e G". Se observó todavía que la viscosidad compleja del pulpa de membrillo aumenta con la concentración para todo el rango de frecuencias estudiadas.
Resumo:
Lysinurinen proteiini-intoleranssi (LPI) on suomalaiseen tautiperintöön kuuluva kationisten aminohappojen, arginiinin, ornitiinin ja lysiinin, kuljetushäiriö suolen ja munuaistubulusten basolateraalisilla kalvoilla. Arginiinin ja ornitiinin puute aiheuttaa häiriöitä ureasyklin toiminnassa, aterian jälkeistä hyperammonemiaa ja proteiiniaversiota. Lysiinin puute vaikuttaa mm. kasvuun ja puolustusmekanismeihin. Hoidossa keskeistä on vähäproteiininen ruokavalio ja L-sitrulliinilisä, joka parantaa ureasyklin toimintaa. Koska LPI-tauti on kuvattu vasta 1960-luvulla, sen luonnollinen kulku tunnetaan vielä huonosti. Tautiin liittyvistä komplikaatioista vakavimmat ovat toistaiseksi tuntemattomalla mekanismilla kehittyvä keuhkojen alveolaarinen proteinoosi ja munuaisongelmat. Suomalaisista LPI-potilaista noin kolmanneksella on havaittu merkkejä munuaisten vajaatoiminnasta, ja muutamilla potilailla munuaisongelmat ovat edenneet loppuvaiheen munuaistautiin (ESRD) saakka. Potilaiden munuaisongelmia tutkittiin viimeksi vuonna 2007. Tämän tutkimuksen tarkoitus oli selvittää, onko LPI-potilaiden munuaisfunktio olennaisesti muuttunut seuranta-aikana 2007-2013. LPI-potilaiden seuranta on valtakunnallisesti keskitetty Turun yliopistollisen keskussairaalan (Tyks) lastenklinikan aineenvaihduntapoliklinikalle. Seurannassa on 41 potilasta, jotka käyvät Tyks:ssä 1—2 kertaa vuodessa. Tässä tutkimuksessa analysoitiin näiden LPI-potilaiden sairaskertomuksia ja laboratoriotutkimuksia. Kiinnostuksen kohteena olivat erityisesti verenpaine, munuaisten toimintatestit, virtsan proteiini- ja aminohappopitoisuudet ja plasman sitrulliinipituisuus. Munuaisten vajaatoiminnan kehitystä arvioitiin seuraamalla seerumin kystatiini C:n, kreatiniinipitoisuuksien ja virtsan beta2-mikroglobuliinipitoisuuksien muutoksia ajan funktiona. Tutkimuksessa havaittiin, että seuranta-ajan loppuun mennessä suurimmalla osalla potilaista oli merkkejä munuaisten vajaatoiminnasta ja osalle potilaista oli kehittynyt vakava munuaisvaurio, joka vaati dialyysihoitoa tai munuaissiirron. Munuaisongelmien määrä oli lisääntynyt seuranta-aikana, vaikka potilaiden munuaisfunktiota oli seurattu säännöllisesti ja riskitekijöitä hoidettu. Sitrulliiniannostuksella ei näyttänyt olevan yhteyttä munuaisten vajaatoiminnan kehittymiseen. Munuaissiirtopotilaista yksi potilas menetti siirrännäisen, muutoin elinsiirtopotilaiden munuaisfunktio on säilynyt tyydyttävänä. Lisäksi havaittiin, että virtsan beeta-2-mikroglobuliinimäärityksellä pystytään havaitsemaan munuaisten vajaatoiminta varhaisessa vaiheessa tässä potilasryhmässä.
Resumo:
INTRODUÇÃO: A insuficiência renal aguda (IRA) nefrotóxica é frequente e importante causa de morbimortalidade. OBJETIVO: Avaliar a prevalência, o curso clínico e o desfecho da IRA nefrotóxica. PACIENTES e MÉTODOS: Coorte histórica realizada em um hospital de ensino terciário, no período de fevereiro a novembro de 1997. Foram incluídos pacientes acima de 12 anos, com diagnóstico de IRA, acompanhados pela equipe de Interconsulta de Nefrologia. Foram excluídos transplantados renais, portadores de insuficiência renal crônica, dialisados por intoxicação exógena e aqueles transferidos de hospital durante o tratamento. RESULTADOS: Dos 234 pacientes acompanhados, 12% apresentaram IRA nefrotóxica e 24%, IRA multifatorial associada ao uso de drogas nefrotóxica. Entre as comorbidades mais prevalentes, estão hipertensão arterial, hepatopatias, neoplasias, insuficiência cardíaca congestiva e diabetes mellitus. Quinze por cento necessitaram de diálise, e o tipo mais frequentemente usado foi hemodiálise venovenosa contínua; 42% eram oligúricos, 44,7% evoluíram para óbito e 33% recuperaram a função renal. Antibióticos, AINH e contraste radiológico foram as drogas nefrotóxicas mais prevalentes.Os medicamentos nefrotóxicos implicados foram, em ordem de frequência, vancomicina, aminoglicosídeos, aciclovir, quimioterápicos e contraste radiológico. Hepatopatia foi a única variável com significância estatística (p = 0,03, IC = 1,08 a 6,49) em análise multivariada. Na comparação entre IRA nefrotóxica e não nefrotóxica, houve aumento da mortalidade proporcionalmente aos dias de internação. CONCLUSÃO: IRA nefrotóxica é frequente, grave e deve ser continuamente monitorada, tanto ambulatorialmente quanto no ambiente intra-hospitalar.