Mobilization and removing of cadmium from kidney by GMDTC utilizing renal glucose reabsorption pathway

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Tang, Xiaojiang, E-mail: river-t@126.com [Guangdong Medical Laboratory Animal Center (China); Zhu, Jinqiu [Department of Epidemiology and Environmental Health, The State University of New York, Buffalo, NY (United States); Zhong, Zhiyong; Luo, Minhui; Li, Guangxian [Guangdong Medical Laboratory Animal Center (China); Gong, Zhihong [Department of Epidemiology and Environmental Health, The State University of New York, Buffalo, NY (United States); Zhang, Chenzi; Fei, Fan [Guangdong Medical Laboratory Animal Center (China); Ruan, Xiaolin [Guangdong Poison Control Center (China); Zhou, Jinlin [Golden Health (Foshan) Technology Co., Ltd (China); Liu, Gaofeng [School of Chemistry and Chemical Engineering, Sun Yat-Sen University (China); Li, Guoding [Guangdong Medical Laboratory Animal Center (China); Olson, James [Department of Epidemiology and Environmental Health, The State University of New York, Buffalo, NY (United States); Department of Pharmacology and Toxicology, The State University of New York, Buffalo, NY (United States); Ren, Xuefeng, E-mail: xuefengr@buffalo.edu [Guangdong Medical Laboratory Animal Center (China); Department of Epidemiology and Environmental Health, The State University of New York, Buffalo, NY (United States); Department of Pharmacology and Toxicology, The State University of New York, Buffalo, NY (United States)

2016-08-15

Chronic exposure to cadmium compounds (Cd{sup 2+}) is one of the major public health problems facing humans in the 21st century. Cd{sup 2+} in the human body accumulates primarily in the kidneys which leads to renal dysfunction and other adverse health effects. Efforts to find a safe and effective drug for removing Cd{sup 2+} from the kidneys have largely failed. We developed and synthesized a new chemical, sodium (S)-2-(dithiocarboxylato((2S,3R,4R,5R)-2,3,4,5,6 pentahydroxyhexyl)amino)-4-(methylthio) butanoate (GMDTC). Here we report that GMDTC has a very low toxicity with an acute lethal dose (LD50) of more than 10,000 mg/kg or 5000 mg/kg body weight, respectively, via oral or intraperitoneal injection in mice and rats. In in vivo settings, up to 94% of Cd{sup 2+} deposited in the kidneys of Cd{sup 2+}-laden rabbits was removed and excreted via urine following a safe dose of GMDTC treatment for four weeks, and renal Cd{sup 2+} level was reduced from 12.9 μg/g to 1.3 μg/g kidney weight. We observed similar results in the mouse and rat studies. Further, we demonstrated both in in vitro and in animal studies that the mechanism of transporting GMDTC and GMDTC-Cd complex into and out of renal tubular cells is likely assisted by two glucose transporters, sodium glucose cotransporter 2 (SGLT2) and glucose transporter 2 (GLUT2). Collectively, our study reports that GMDTC is safe and highly efficient in removing deposited Cd{sup 2+} from kidneys assisted by renal glucose reabsorption system, suggesting that GMDTC may be the long-pursued agent used for preventive and therapeutic purposes for both acute and chronic Cd{sup 2+} exposure.

Angiotensin II AT1 receptor blockade decreases vasopressin-induced water reabsorption and AQP2 levels in NaCl-restricted rats

DEFF Research Database (Denmark)

Kwon, Tae-Hwan; Nielsen, Jakob; Knepper, M.A.

2005-01-01

Vasopressin and ANG II, which are known to play a major role in renal water and sodium reabsorption, are mainly coupled to the cAMP/PKA and phosphoinositide pathways, respectively. There is evidence for cross talk between these intracellular signaling pathways. We therefore hypothesized that vaso......Vasopressin and ANG II, which are known to play a major role in renal water and sodium reabsorption, are mainly coupled to the cAMP/PKA and phosphoinositide pathways, respectively. There is evidence for cross talk between these intracellular signaling pathways. We therefore hypothesized...

PGE2 receptor EP3 inhibits water reabsorption and contributes to polyuria and kidney injury in a streptozotocin-induced mouse model of diabetes.

Science.gov (United States)

Hassouneh, Ramzi; Nasrallah, Rania; Zimpelmann, Joe; Gutsol, Alex; Eckert, David; Ghossein, Jamie; Burns, Kevin D; Hébert, Richard L

2016-06-01

The first clinical manifestation of diabetes is polyuria. The prostaglandin E2 (PGE2) receptor EP3 antagonises arginine vasopressin (AVP)-mediated water reabsorption and its expression is increased in the diabetic kidney. The purpose of this work was to study the contribution of EP3 to diabetic polyuria and renal injury. Male Ep 3 (-/-) (also known as Ptger3 (-/-)) mice were treated with streptozotocin (STZ) to generate a mouse model of diabetes and renal function was evaluated after 12 weeks. Isolated collecting ducts (CDs) were microperfused to study the contribution of EP3 to AVP-mediated fluid reabsorption. Ep 3 (-/-)-STZ mice exhibited attenuated polyuria and increased urine osmolality compared with wild-type STZ (WT-STZ) mice, suggesting enhanced water reabsorption. Compared with WT-STZ mice, Ep 3 (-/-)-STZ mice also had increased protein expression of aquaporin-1, aquaporin-2, and urea transporter A1, and reduced urinary AVP excretion, but increased medullary V2 receptors. In vitro microperfusion studies indicated that Ep 3 (-/-) and WT-STZ CDs responded to AVP stimulation similarly to those of wild-type mice, with a 60% increase in fluid reabsorption. In WT non-injected and WT-STZ mice, EP3 activation with sulprostone (PGE2 analogue) abrogated AVP-mediated water reabsorption; this effect was absent in mice lacking EP3. A major finding of this work is that Ep 3 (-/-)-STZ mice showed blunted renal cyclooxygenase-2 protein expression, reduced renal hypertrophy, reduced hyperfiltration and reduced albuminuria, as well as diminished tubular dilation and nuclear cysts. Taken together, the data suggest that EP3 contributes to diabetic polyuria by inhibiting expression of aquaporins and that it promotes renal injury during diabetes. EP3 may prove to be a promising target for more selective management of diabetic kidney disease.

Effects of intravenous bumetanide administration on renal haemodynamics and proximal and distal tubular sodium reabsorption in conscious rats

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Shalmi, M.; Petersen, J.S.; Christensen, S. (Department of pharmacology, University of Copenhagen (Denmark))

1989-01-01

The renal effects of 0.02-62.5 mg/kg bumetanide given as intravenous bolus injections were studied in water diuretic conscious rats. Clearances of {sup 14}C-tetraethylammonium, {sup 3}H-inulin and lithium were used as markers for renal plasma flow (RPF), glomerular filtion rate (GFR) and proximal tubular output, respectively. Bumetanide caused biphasic, transient and dose-independent changes in the renal haemodynamics without significant alterations of the filtration fraction. At dose-levels above 0.02 mg/kg bumetanide increased urine flow, absolute and fractional Na excretion as well as the indices for fractional output of Na from the proximal tubules (C{sub Li}/C{sub I}n) and the distal nephron segments (C{sub Na}/C{sub Li}). The changes in C{sub Li}/C{sub In} became maximal at doses above 0.5 mg/kg, whereas C{sub Na}/C{sub Li} was increased with the dose up to 12.5 mg/kg. Paradoxically, doses above 12.5 mg/kg were less natriuretic due to a decrease of C{sub Na}/C{sub Li}. It is concluded that in rats bumetanide is an effective although short-acting diuretic when administered intravenously. When comparing peak responses bumetanide is equipotent to furosemide but has a lower maximal efficacy. Judged from the changes in fractional lithium excretion, the natriuretic effect of bumetanide is effected by inhibition of Na reabsorption in the proximal tubule in addition to the well-known effect on the distal nephron segment. (author).

Renal albumin absorption in physiology and pathology.

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Birn, H; Christensen, E I

2006-02-01

Albumin is the most abundant plasmaprotein serving multiple functions as a carrier of metabolites, hormones, vitamins, and drugs, as an acid/base buffer, as antioxidant and by supporting the oncotic pressure and volume of the blood. The presence of albumin in urine is considered to be the result of the balance between glomerular filtration and tubular reabsorption. Albuminuria has been accepted as an independent risk factor and a marker for renal as well as cardiovascular disease, and during the past decade, evidence has suggested that albumin itself may cause progression of renal disease. Thus, the reduction of proteinuria and, in particular, albuminuria has become a target in itself to prevent deterioration of renal function. Studies have shown albumin and its ligands to induce expression of inflammatory and fibrogenic mediators, and it has been hypothesized that increased filtration of albumin causes excessive tubular reabsorption, resulting in inflammation and fibrosis, resulting in the loss of renal function. In addition, it is known that tubular dysfunction in itself may cause albuminuria owing to decreased reabsorption of filtered albumin, and, recently, it has been suggested that significant amounts of albumin fragments are excreted in the urine as a result of tubular degradation. Thus, although both tubular and glomerular dysfunction influences renal handling of albumin, it appears that tubular reabsorption plays a central role in mediating the effects of albumin on renal function. The present paper will review the mechanisms for tubular albumin uptake and the possible implications for the development of renal disease.

Regulation of renal NaPi-2 expression and tubular phosphate reabsorption by growth hormone in the juvenile rat.

Science.gov (United States)

Woda, Craig B; Halaihel, Nabil; Wilson, Paul V; Haramati, Aviad; Levi, Moshe; Mulroney, Susan E

2004-07-01

Growth hormone (GH) is an important factor in the developmental adaptation to enhance P(i) reabsorption; however, the nephron sites and mechanisms by which GH regulates renal P(i) uptake remain unclear and are the focus of the present study. Micropuncture experiments were performed after acute thyroparathyroidectomy in the presence and absence of parathyroid hormone (PTH) in adult (14- to 17-wk old), juvenile (4-wk old), and GH-suppressed juvenile male rats. While the phosphaturic effect of PTH was blunted in the juvenile rat compared with the adult, suppression of GH in the juvenile restored fractional P(i) excretion to adult levels. In the presence or absence of PTH, GH suppression in the juvenile rat caused a significant increase in the fractional P(i) delivery to the late proximal convoluted (PCT) and early distal tubule, so that delivery was not different from that in adults. These data were confirmed by P(i) uptake studies into brush-border membrane (BBM) vesicles. Immunofluorescence studies indicate increased BBM type IIa NaP(i) cotransporter (NaPi-2) expression in the juvenile compared with adult rat, and GH suppression reduced NaPi-2 expression to levels observed in the adult. GH replacement in the [N-acetyl-Tyr(1)-d-Arg(2)]-GRF-(1-29)-NH(2)-treated juveniles restored high NaPi-2 expression and P(i) uptake. Together, these novel results demonstrate that the presence of GH in the juvenile animal is crucial for the early developmental upregulation of BBM NaPi-2 and, most importantly, describe the enhanced P(i) reabsorption along the PCT and proximal straight nephron segments in the juvenile rat.

Renal vein oxygen saturation in renal artery stenosis

DEFF Research Database (Denmark)

Nielsen, K; Rehling, M; Henriksen, Jens Henrik Sahl

1992-01-01

Renal vein oxygen-saturation was measured in 56 patients with arterial hypertension and unilateral stenosis or occlusion of the renal artery. Oxygen-saturation in blood from the ischaemic kidney (84.4%, range 73-93%) was significantly higher than that from the 'normal' contralateral kidney (81...... than its blood flow. This is probably due to decreased filtration fraction and filtered sodium with subsequent reduction in absolute tubular re-absorption of sodium ions....

Paracellular transport and energy utilization in the renal tubule.

Science.gov (United States)

Yu, Alan S L

2017-09-01

Paracellular transport across the tight junction is a general mechanism for transepithelial transport of solutes in epithelia, including the renal tubule. However, why paracellular transport evolved, given the existence of a highly versatile system for transcellular transport, is unknown. Recent studies have identified the paracellular channel, claudin-2, that is responsible for paracellular reabsorption of sodium in the proximal renal tubule. Knockout of claudin-2 in mice impairs proximal sodium and fluid reabsorption but is compensated by upregulation of sodium reabsorption in the loop of Henle. This occurs at the expense of increased renal oxygen consumption, hypoxia of the outer medulla and increased susceptibility to ischemic kidney injury. Paracellular transport can be viewed as a mechanism to exploit the potential energy in existing electrochemical gradients to drive passive transepithelial transport without consuming additional energy. In this way, it enhances the efficiency of energy utilization by transporting epithelia.

Hepatic, renal, and total body galactose elimination in the pig

DEFF Research Database (Denmark)

Winkler, K; Henriksen, Jens Henrik Sahl; Tygstrup, N

1993-01-01

Galactose elimination capacity is used as a quantitative measure of liver function on the assumption that galactose elimination outside the liver is negligible or easily corrected for. The relationship between hepatic and extrahepatic removal of galactose was studied in anesthetized pigs during...... reabsorption (Tm 178 +/- 3.0 mumol/min, Km 3.8 +/- 0.9 mmol/l, n = 20). Metabolic conversion of galactose in the kidney was not demonstrable. At all concentrations studied (0.4-5.8 mmol/l), total galactose elimination from the body exceeded the sum of hepatic and renal elimination by approximately 100 mumol....../min, independent of the concentration. At blood concentrations usually used for clinical estimation of the galactose elimination capacity (approximately 4 mmol/l), hepatic removal in the pig accounted for 55% and renal removal for 30% of total removal; 15% of removal occurred in other organs. We conclude...

Renal Blood Flow, Glomerular Filtration Rate, and Renal Oxygenation in Early Clinical Septic Shock.

Science.gov (United States)

Skytte Larsson, Jenny; Krumbholz, Vitus; Enskog, Anders; Bragadottir, Gudrun; Redfors, Bengt; Ricksten, Sven-Erik

2018-06-01

Data on renal hemodynamics, function, and oxygenation in early clinical septic shock are lacking. We therefore measured renal blood flow, glomerular filtration rate, renal oxygen consumption, and oxygenation in patients with early septic shock. Prospective comparative study. General and cardiothoracic ICUs. Patients with norepinephrine-dependent early septic shock (n = 8) were studied within 24 hours after arrival in the ICU and compared with postcardiac surgery patients without acute kidney injury (comparator group, n = 58). None. Data on systemic hemodynamics and renal variables were obtained during two 30-minute periods. Renal blood flow was measured by the infusion clearance of para-aminohippuric acid, corrected for renal extraction of para-aminohippuric acid. Renal filtration fraction was measured by renal extraction of chromium-51 labeled EDTA. Renal oxygenation was estimated from renal oxygen extraction. Renal oxygen delivery (-24%; p = 0.037) and the renal blood flow-to-cardiac index ratio (-21%; p = 0.018) were lower, renal vascular resistance was higher (26%; p = 0.027), whereas renal blood flow tended to be lower (-19%; p = 0.068) in the septic group. Glomerular filtration rate (-32%; p = 0.006) and renal sodium reabsorption (-29%; p = 0.014) were both lower in the septic group. Neither renal filtration fraction nor renal oxygen consumption differed significantly between groups. Renal oxygen extraction was significantly higher in the septic group (28%; p = 0.022). In the septic group, markers of tubular injury were elevated. In early clinical septic shock, renal function was lower, which was accompanied by renal vasoconstriction, a lower renal oxygen delivery, impaired renal oxygenation, and tubular sodium reabsorption at a high oxygen cost compared with controls.

Sodium glucose co-transporter 2 inhibitors: blocking renal tubular reabsorption of glucose to improve glycaemic control in patients with diabetes.

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Jabbour, S A; Goldstein, B J

2008-08-01

The kidney plays a central role in the regulation of plasma glucose levels, although until recently this has not been widely appreciated or considered a target for therapeutic intervention. The sodium glucose co-transporter type 2 (SGLT2) located in the plasma membrane of cells lining the proximal tubule mediates the majority of renal glucose reabsorption from the tubular fluid, which normally prevents the loss of glucose in the urine. Competitive inhibitors of SGLT2 that provoke the renal excretion of glucose have been discovered, thereby providing a unique mechanism to potentially lower the elevated blood glucose levels in patients with diabetes. To explore the physiology of SGLT2 action and discuss several SGLT2 inhibitors that have entered early clinical development. All publicly available data were identified by searching the internet for 'SGLT2' and 'SGLT2 inhibitor' through 1 November 2007. Published articles, press releases and abstracts presented at national and international meetings were considered. Sodium glucose co-transporter type 2 inhibition is a novel treatment option for diabetes, which has been studied in preclinical models and a few potent and selective SGLT2 inhibitors have been reported and are currently in clinical development. These agents appear to be safe and generally well tolerated, and will potentially be a beneficial addition to the growing battery of oral antihyperglycaemic agents.

Renal Control of Calcium, Phosphate, and Magnesium Homeostasis

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Chonchol, Michel; Levi, Moshe

2015-01-01

Calcium, phosphate, and magnesium are multivalent cations that are important for many biologic and cellular functions. The kidneys play a central role in the homeostasis of these ions. Gastrointestinal absorption is balanced by renal excretion. When body stores of these ions decline significantly, gastrointestinal absorption, bone resorption, and renal tubular reabsorption increase to normalize their levels. Renal regulation of these ions occurs through glomerular filtration and tubular reabsorption and/or secretion and is therefore an important determinant of plasma ion concentration. Under physiologic conditions, the whole body balance of calcium, phosphate, and magnesium is maintained by fine adjustments of urinary excretion to equal the net intake. This review discusses how calcium, phosphate, and magnesium are handled by the kidneys. PMID:25287933

Renoprotective Effects of SGLT2 Inhibitors: Beyond Glucose Reabsorption Inhibition.

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Tsimihodimos, V; Filippatos, T D; Filippas-Ntekouan, S; Elisaf, M

2017-01-01

Sodium-glucose co-transporter 2 (SGLT2) inhibitors are a new class of antidiabetic drugs that inhibit glucose and sodium reabsorption at proximal tubules. These drugs may exhibit renoprotective properties, since they prevent the deterioration of the glomerular filtration rate and reduce the degree of albuminuria in patients with diabetes-associated kidney disease. In this review we consider the pathophysiologic mechanisms that have been recently implicated in the renoprotective properties of SGLT2 inhibitors. The beneficial effects of SGLT2 inhibitors on the conventional risk factors for kidney disease (such as blood pressure, hyperglycaemia, body weight and serum uric acid levels) may explain, at least in part, the observed renal-protecting properties of these compounds. However, it has been hypothesized that the most important mechanisms for this phenomenon include the reduction in the intraglomerular pressure, the changes in the local and systemic degree of activation of the renin-aldosterone-angiotensin system and a shift in renal fuel consumption towards more efficient energy substrates such as ketone bodies. The beneficial effects of SGLT2 inhibitors on various aspects of renal function make them an attractive choice in patients with (and possibly without) diabetes-associated renal impairment. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Experimental dissociation of the effects of prostaglandins on renal sodium and water reabsorption by cyclo-oxygenase inhibitors in the rat.

Science.gov (United States)

Bartoli, E; Branca, G F; Faedda, R; Olmeo, N A; Satta, A; Soggia, G

1982-07-01

1 The relative importance of the effect of prostaglandins on renal sodium and water reabsorption was assessed in rats. 2 Clearance experiments were performed on 24 anaesthetized rats divided into 3 groups. Each group was infused throughout either with Ringer solution at 9 ml/h (Protocol I), or at 3 ml/h (Protocol II) or with hypotonic fluid at 5 ml/h (Protocol III). Clearance periods were performed before and after intravenous injection of indomethacin (5 mg/kg) and then of aspirin (20 mg/kg). The natriuretic response to different degrees of volume expansion was not modified during the action of the inhibitors. 3 When baseline urine osmolality (Uosm) was high (Protocol II) no further increase occurred in the presence of prostaglandin inhibition. Conversely, Uosm rose from 771 +/- 134 to 1356 +/- 414 and from 575 +/- 245 to 841 +/- 407 mosm/kg (P less than 0.05) in Protocol I and Protocol III respectively, when antidiuretic hormone secretion was inhibited by the higher degree of volume expansion. 4 There was a significant correlation between the change in urine flow rate induced by cyclooxygenase inhibitors and the attendant variations in Na excretion, r = 0.42, n = 41, P less than 0.01. 5 Thus, prostaglandins affect Na loss during saline load as a side effect of their action on water permeability. They could play an important role in volume depletion by counterbalancing the large secretion rate of renal vasoconstrictors.

Experimental dissociation of the effects of prostaglandins on renal sodium and water reabsorption by cyclo-oxygenase inhibitors in the rat.

Science.gov (United States)

Bartoli, E.; Branca, G. F.; Faedda, R.; Olmeo, N. A.; Satta, A.; Soggia, G.

1982-01-01

1 The relative importance of the effect of prostaglandins on renal sodium and water reabsorption was assessed in rats. 2 Clearance experiments were performed on 24 anaesthetized rats divided into 3 groups. Each group was infused throughout either with Ringer solution at 9 ml/h (Protocol I), or at 3 ml/h (Protocol II) or with hypotonic fluid at 5 ml/h (Protocol III). Clearance periods were performed before and after intravenous injection of indomethacin (5 mg/kg) and then of aspirin (20 mg/kg). The natriuretic response to different degrees of volume expansion was not modified during the action of the inhibitors. 3 When baseline urine osmolality (Uosm) was high (Protocol II) no further increase occurred in the presence of prostaglandin inhibition. Conversely, Uosm rose from 771 +/- 134 to 1356 +/- 414 and from 575 +/- 245 to 841 +/- 407 mosm/kg (P less than 0.05) in Protocol I and Protocol III respectively, when antidiuretic hormone secretion was inhibited by the higher degree of volume expansion. 4 There was a significant correlation between the change in urine flow rate induced by cyclooxygenase inhibitors and the attendant variations in Na excretion, r = 0.42, n = 41, P less than 0.01. 5 Thus, prostaglandins affect Na loss during saline load as a side effect of their action on water permeability. They could play an important role in volume depletion by counterbalancing the large secretion rate of renal vasoconstrictors. PMID:6809089

Inhibition of renal glucose reabsorption as a novel treatment for diabetes patients

Directory of Open Access Journals (Sweden)

Eugenio Cersosimo

2014-03-01

Full Text Available The importance of the kidney in glucose homeostasis has been recognized for many years. Recent observations indicating a greater role of renal glucose metabolism in various physiologic and pathologic conditions have rekindled the interest in renal glucose handling as a potential target for the treatment of diabetes. The enormous capacity of the proximal tubular cells to reabsorb the filtered glucose load entirely, utilizing the sodium-glucose co-transporter system (primarily SGLT-2, became the focus of attention. Original studies conducted in experimental animals with the nonspecific SGLT inhibitor phlorizin showed that hyperglycemia after pancreatectomy decreased as a result of forced glycosuria. Subsequently, several compounds with more selective SGLT-2 inhibition properties (“second-generation” were developed. Some agents made it into pre-clinical and clinical trials and a few have already been approved for commercial use in the treatment of type 2 diabetes. In general, a 6-month period of therapy with SGLT-2 inhibitors is followed by a mean urinary glucose excretion rate of ~80 g/day accompanied by a decline in fasting and postprandial glucose with average decreases in HgA1C ~1.0%. Concomitant body weight loss and a mild but consistent drop in blood pressure also have been reported. In contrast, transient polyuria, thirst with dehydration and occasional hypotension have been described early in the treatment. In addition, a significant increase in the occurrence of uro-genital infections, particularly in women has been documented with the use of SGLT-2 inhibitors. Conclusion: Although long-term cardiovascular, renal and bone/mineral effects are unknown SGLT-2 inhibitors, if used with caution and in the proper patient provide a unique insulin-independent therapeutic option in the management of obese type 2 diabetes patients.

Roles of renal ammonia metabolism other than in acid-base homeostasis.

Science.gov (United States)

Weiner, I David

2017-06-01

The importance of renal ammonia metabolism in acid-base homeostasis is well known. However, the effects of renal ammonia metabolism other than in acid-base homeostasis are not as widely recognized. First, ammonia differs from almost all other solutes in the urine in that it does not result from arterial delivery. Instead, ammonia is produced by the kidney, and only a portion of the ammonia produced is excreted in the urine, with the remainder returned to the systemic circulation through the renal veins. In normal individuals, systemic ammonia addition is metabolized efficiently by the liver, but in patients with either acute or chronic liver disease, conditions that increase the addition of ammonia of renal origin to the systemic circulation can result in precipitation and/or worsening of hyperammonemia. Second, ammonia appears to serve as an intrarenal paracrine signaling molecule. Hypokalemia increases proximal tubule ammonia production and secretion as well as reabsorption in the thick ascending limb of the loop of Henle, thereby increasing delivery to the renal interstitium and the collecting duct. In the collecting duct, ammonia decreases potassium secretion and stimulates potassium reabsorption, thereby decreasing urinary potassium excretion and enabling feedback correction of the initiating hypokalemia. Finally, the stimulation of renal ammonia metabolism by hypokalemia may contribute to the development of metabolic alkalosis, which in turn can stimulate NaCl reabsorption and contribute to the intravascular volume expansion, increased blood pressure and diuretic resistance that can develop with hypokalemia. The evidence supporting these novel non-acid-base roles of renal ammonia metabolism is discussed in this review.

Hypocapnic but not metabolic alkalosis impairs alveolar fluid reabsorption.

Science.gov (United States)

Myrianthefs, Pavlos M; Briva, Arturo; Lecuona, Emilia; Dumasius, Vidas; Rutschman, David H; Ridge, Karen M; Baltopoulos, George J; Sznajder, Jacob Iasha

2005-06-01

Acid-base disturbances, such as metabolic or respiratory alkalosis, are relatively common in critically ill patients. We examined the effects of alkalosis (hypocapnic or metabolic alkalosis) on alveolar fluid reabsorption in the isolated and continuously perfused rat lung model. We found that alveolar fluid reabsorption after 1 hour was impaired by low levels of CO2 partial pressure (PCO2; 10 and 20 mm Hg) independent of pH levels (7.7 or 7.4). In addition, PCO2 higher than 30 mm Hg or metabolic alkalosis did not have an effect on this process. The hypocapnia-mediated decrease of alveolar fluid reabsorption was associated with decreased Na,K-ATPase activity and protein abundance at the basolateral membranes of distal airspaces. The effect of low PCO2 on alveolar fluid reabsorption was reversible because clearance normalized after correcting the PCO2 back to normal levels. These data suggest that hypocapnic but not metabolic alkalosis impairs alveolar fluid reabsorption. Conceivably, correction of hypocapnic alkalosis in critically ill patients may contribute to the normalization of lung ability to clear edema.

Reactive Oxygen Species Modulation of Na/K-ATPase Regulates Fibrosis and Renal Proximal Tubular Sodium Handling

Directory of Open Access Journals (Sweden)

Jiang Liu

2012-01-01

Full Text Available The Na/K-ATPase is the primary force regulating renal sodium handling and plays a key role in both ion homeostasis and blood pressure regulation. Recently, cardiotonic steroids (CTS-mediated Na/K-ATPase signaling has been shown to regulate fibrosis, renal proximal tubule (RPT sodium reabsorption, and experimental Dahl salt-sensitive hypertension in response to a high-salt diet. Reactive oxygen species (ROS are an important modulator of nephron ion transport. As there is limited knowledge regarding the role of ROS-mediated fibrosis and RPT sodium reabsorption through the Na/K-ATPase, the focus of this review is to examine the possible role of ROS in the regulation of Na/K-ATPase activity, its signaling, fibrosis, and RPT sodium reabsorption.

Testosterone increases urinary calcium excretion and inhibits expression of renal calcium transport proteins.

NARCIS (Netherlands)

Hsu, Y.J.; Dimke, H.; Schoeber, J.P.H.; Hsu, S.C.; Lin, S.H.; Chu, P.; Hoenderop, J.G.J.; Bindels, R.J.M.

2010-01-01

Although gender differences in the renal handling of calcium have been reported, the overall contribution of androgens to these differences remains uncertain. We determined here whether testosterone affects active renal calcium reabsorption by regulating calcium transport proteins. Male mice had

Tick-Tock Chimes the Kidney Clock – from Biology of Renal Ageing to Clinical Applications

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Joshua Rowland

2018-01-01

Full Text Available Ageing of the kidney is a multi-dimensional process that occurs simultaneously at the molecular, cellular, histological, anatomical and physiological level. Nephron number and renal cortical volume decline, renal tubules become atrophic and glomeruli become sclerotic with age. These structural changes are accompanied by a decline in glomerular filtration rate, decreased sodium reabsorption and potassium excretion, reduced urinary concentrating capacity and alterations in the endocrine activity of the kidney. However, the pace of progression of these changes is not identical in everyone - individuals of the same age and seemingly similar clinical profile often exhibit stark differences in the age-related decline in renal health. Thus, chronological age poorly reflects the time-dependent changes that occur in the kidney. An ideal measure of renal vitality is biological kidney age – a measure of the age-related changes in physiological function. Replacing chronological age with biological age could provide numerous clinical benefits including improved prognostic accuracy in renal transplantation, better stratification of risk and identification of those who are on a fast trajectory to an age-related drop in kidney health.

Mathematical rationalization for the renal tubular transport: revised concepts.

Science.gov (United States)

Mioni, Roberto; Marega, Alessandra; Romano, Giulio; Montanaro, Domenico

2017-09-01

The current emphasis on kinetics and in situ control of molecular exchanges, across the tubular membrane, has not been paralleled by corresponding improvements in our understanding of tubular behaviour at the macroscopic level of classical physiology. In this paper, we propose a mathematical rationalization of macroscopic tubular transport by means of a principal transport equation, originating from the law of mass action between substrate and carrier. The other equations, derived from the main one, demonstrate the possibility of distinguishing between transporters with low affinity and high capacity and transporters with high affinity and low capacity. Moreover, our model formalizes both tubular reabsorption and tubular secretion. Regarding the renal calcium handling, our model confirms the two-compartment system proposed by Mioni in 1971, with some important variants, which are in agreement with the fractional reabsorptions of this cation along the tubule, as verified by micro-puncture technique. To obtain the frequency distribution of saturated tubules, we have utilized the infinitesimal analysis method, starting from the equations proposed by Smith in 1943, concluding that all titration curves result from the combined effect of enzymatic approach and anatomical heterogeneity of the nephrons. The theoretical equations included in our manuscript reflect substantial and palpable physiological mechanisms able to suggest diagnosis and therapy of some electrolyte and hormonal disorders. At the end of this paper, we highlight advantages and disadvantages detectable by comparing our mathematical approach with Marshall's and Bijvoet's methods, proposed, respectively, in 1976 and 1984.

Towards a system-based pharmacology approach to predict developmental changes in renal drug clearance in children

NARCIS (Netherlands)

De Cock, Roosmarijn Frieda Wilfried

2014-01-01

Renal clearance is responsible for the elimination of a large number of water-soluble drugs and metabolites and is therefore of large importance when characterizing the pharmacokinetics of drugs. Renal clearance includes glomerular filtration, tubular secretion and reabsorption and each of these

Albumin-derived peptides efficiently reduce renal uptake of radiolabelled peptides

International Nuclear Information System (INIS)

Vegt, Erik; Eek, Annemarie; Oyen, Wim J.G.; Gotthardt, Martin; Boerman, Otto C.; Jong, Marion de

2010-01-01

In peptide-receptor radionuclide therapy (PRRT), the maximum activity dose that can safely be administered is limited by high renal uptake and retention of radiolabelled peptides. The kidney radiation dose can be reduced by coinfusion of agents that competitively inhibit the reabsorption of radiolabelled peptides, such as positively charged amino acids, Gelofusine, or trypsinised albumin. The aim of this study was to identify more specific and potent inhibitors of the kidney reabsorption of radiolabelled peptides, based on albumin. Albumin was fragmented using cyanogen bromide and six albumin-derived peptides with different numbers of electric charges were selected and synthesised. The effect of albumin fragments (FRALB-C) and selected albumin-derived peptides on the internalisation of 111 In-albumin, 111 In-minigastrin, 111 In-exendin and 111 In-octreotide by megalin-expressing cells was assessed. In rats, the effect of Gelofusine and albumin-derived peptides on the renal uptake and biodistribution of 111 In-minigastrin, 111 In-exendin and 111 In-octreotide was determined. FRALB-C significantly reduced the uptake of all radiolabelled peptides in vitro. The albumin-derived peptides showed different potencies in reducing the uptake of 111 In-albumin, 111 In-exendin and 111 In-minigastrin in vitro. The most efficient albumin-derived peptide (peptide 6), was selected for in vivo testing. In rats, 5 mg of peptide 6 very efficiently inhibited the renal uptake of 111 In-minigastrin, by 88%. Uptake of 111 In-exendin and 111 In-octreotide was reduced by 26 and 33%, respectively. The albumin-derived peptide 6 efficiently inhibited the renal reabsorption of 111 In-minigastrin, 111 In-exendin and 111 In-octreotide and is a promising candidate for kidney protection in PRRT. (orig.)

Observations on the mechanism and location of ascites reabsorption in man

International Nuclear Information System (INIS)

Rector, W.G. Jr.; Ibarra, F.

1987-01-01

Animal data indicate that ascites is reabsorbed by a lymphatic mechanism and that these vessels are subdiaphragmatic in location. We evaluated the relative role of lymphatics in ascites reabsorption in man by comparing the ascites clearance and plasma appearance rates of intraperitoneally injected radiolabeled albumin to those of intraperitoneally injected labeled autologous red blood cells, which require, owing to their large size, lymphatic removal, in patients with cirrhosis and ascites. To evaluate the location of reabsorption, we repeated these measurements after replacing ascites in the subdiaphragmatic region with 500-1000 ml of intraperitoneally injected air, reasoning that this maneuver should slow or eliminate ascites reabsorption occurring at this site. We found that the transfer rates of albumin and red cells out of ascites were similar and that creation of pneumoperitoneum did not influence these rates. These data confirm that ascites protein reabsorption occurs via a lymphatic mechanism in man. They suggest, however, that these vessels may not be subdiaphragmatic in location

Roles of Akt and SGK1 in the Regulation of Renal Tubular Transport

Directory of Open Access Journals (Sweden)

Nobuhiko Satoh

2015-01-01

Full Text Available A serine/threonine kinase Akt is a key mediator in various signaling pathways including regulation of renal tubular transport. In proximal tubules, Akt mediates insulin signaling via insulin receptor substrate 2 (IRS2 and stimulates sodium-bicarbonate cotransporter (NBCe1, resulting in increased sodium reabsorption. In insulin resistance, the IRS2 in kidney cortex is exceptionally preserved and may mediate the stimulatory effect of insulin on NBCe1 to cause hypertension in diabetes via sodium retention. Likewise, in distal convoluted tubules and cortical collecting ducts, insulin-induced Akt phosphorylation mediates several hormonal signals to enhance sodium-chloride cotransporter (NCC and epithelial sodium channel (ENaC activities, resulting in increased sodium reabsorption. Serum- and glucocorticoid-inducible kinase 1 (SGK1 mediates aldosterone signaling. Insulin can stimulate SGK1 to exert various effects on renal transporters. In renal cortical collecting ducts, SGK1 regulates the expression level of ENaC through inhibition of its degradation. In addition, SGK1 and Akt cooperatively regulate potassium secretion by renal outer medullary potassium channel (ROMK. Moreover, sodium-proton exchanger 3 (NHE3 in proximal tubules is possibly activated by SGK1. This review focuses on recent advances in understanding of the roles of Akt and SGK1 in the regulation of renal tubular transport.

Localisation and mechanism of renal retention of radiolabelled somatostatin analogues

Energy Technology Data Exchange (ETDEWEB)

Melis, Marleen; Krenning, Eric P.; Bernard, Bert F.; Jong, Marion de [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands); Barone, Raffaella [UCL, Centre of Nuclear Medicine and Laboratory of PET, Brussels (Belgium); Visser, Theo J. [Erasmus MC, Department of Internal Medicine, Rotterdam (Netherlands)

2005-10-01

Radiolabelled somatostatin analogues, such as octreotide and octreotate, are used for tumour scintigraphy and radionuclide therapy. The kidney is the most important critical organ during such therapy owing to the reabsorption and retention of radiolabelled peptides. The aim of this study was to investigate in a rat model both the localisation and the mechanism of renal uptake after intravenous injection of radiolabelled somatostatin analogues. The multi-ligand megalin/cubilin receptor complex, responsible for reabsorption of many peptides and proteins in the kidney, is an interesting candidate for renal endocytosis of these peptide analogues. For localisation studies, ex vivo autoradiography and micro-autoradiography of rat kidneys were performed 1-24 h after injection of radiolabelled somatostatin analogues and compared with the renal anti-megalin immunohistochemical staining pattern. To confirm a role of megalin in the mechanism of renal retention of [{sup 111}In-DTPA]octreotide, the effects of three inhibitory substances were explored in rats. Renal ex vivo autoradiography showed high cortical radioactivity and lower radioactivity in the outer medulla. The distribution of cortical radioactivity was inhomogeneous. Micro-autoradiography indicated that radioactivity was only retained in the proximal tubules. The anti-megalin immunohistochemical staining pattern showed a strong similarity with the renal [{sup 111}In-DTPA]octreotide ex vivo autoradiograms. Biodistribution studies showed that co-injection of positively charged d-lysine reduced renal uptake to 60% of control. Sodium maleate reduced renal [{sup 111}In-DTPA]octreotide uptake to 15% of control. Finally, cisplatin pre-treatment of rats reduced kidney uptake to 70% of control. Renal retention of [{sup 111}In-DTPA]octreotide is confined to proximal tubules in the rat kidney, in which megalin-mediated endocytosis may play an important part. (orig.)

A new human NHERF1 mutation decreases renal phosphate transporter NPT2a expression by a PTH-independent mechanism.

Directory of Open Access Journals (Sweden)

Marie Courbebaisse

Full Text Available BACKGROUND: The sodium-hydrogen exchanger regulatory factor 1 (NHERF1 binds to the main renal phosphate transporter NPT2a and to the parathyroid hormone (PTH receptor. We have recently identified mutations in NHERF1 that decrease renal phosphate reabsorption by increasing PTH-induced cAMP production in the renal proximal tubule. METHODS: We compared relevant parameters of phosphate homeostasis in a patient with a previously undescribed mutation in NHERF1 and in control subjects. We expressed the mutant NHERF1 protein in Xenopus Oocytes and in cultured cells to study its effects on phosphate transport and PTH-induced cAMP production. RESULTS: We identified in a patient with inappropriate renal phosphate reabsorption a previously unidentified mutation (E68A located in the PDZ1 domain of NHERF1.We report the consequences of this mutation on NHERF1 function. E68A mutation did not modify cAMP production in the patient. PTH-induced cAMP synthesis and PKC activity were not altered by E68A mutation in renal cells in culture. In contrast to wild-type NHERF1, expression of the E68A mutant in Xenopus oocytes and in human cells failed to increase phosphate transport. Pull down experiments showed that E68A mutant did not interact with NPT2a, which robustly interacted with wild type NHERF1 and previously identified mutants. Biotinylation studies revealed that E68A mutant was unable to increase cell surface expression of NPT2a. CONCLUSIONS: Our results indicate that the PDZ1 domain is critical for NHERF1-NPT2a interaction in humans and for the control of NPT2a expression at the plasma membrane. Thus we have identified a new mechanism of renal phosphate loss and shown that different mutations in NHERF1 can alter renal phosphate reabsorption via distinct mechanisms.

Evidence of active transport of cadmium complexing dithiocarbamates into renal and hepatic cells in vivo

International Nuclear Information System (INIS)

Gale, G.R.; Smith, A.B.; Jones, M.M.; Singh, P.K.

1992-01-01

A study was made of the effects of certain inhibitors of transport systems on the actions of four cadmium (Cd) complexing N,N-disubstituted dithiocarbamates (DTCs) in mobilizing murine renal and hepatic Cd in vivo. Probenecid, the prototypical antagonist of organic anion transport in the kidney, when given 1 hr prior to each DTC, sharply suppressed the DTC-induced reduction of renal Cd but was virtually without effect on mobilization of Cd from liver. Sulfinpyrazone, which blocks tubular reabsorption of uric acid and also inhibits transport of a variety of organic acids, inhibited markedly the mobilization of both renal and hepatic Cd by DTCs. Phlorizin, an inhibitor of tubular sugar reabsorption, did not affect the Cd mobilizing actions of DTCs in any consistent fashion. We propose that the high degree of selectivity of DTCs in mobilizing renal hepatic Cd is dependent, at lest in part, upon active transport of DTCs into these tissues via the organic anion transport systems. This report presents the first evidence that compounds of the (R) 2 NCSS - class may gain access to intracellular space by an active, carrier-mediated process. (au)

Response of copper deficient rats to inhibitors of renal sodium reabsorption

Energy Technology Data Exchange (ETDEWEB)

Noordewier, B.; Saari, J.T. (Northwestern College, Orange City, IA (United States) USDA/ARS, Grand Forks, ND (United States))

1991-03-11

This study examined the effects of furosemide (Furo), a Loop diuretic, and amiloride (Am), a potassium (K)-sparing diuretic, on the excretion of sodium (Na) and K in copper-adequate (CuAdeq) and copper-deficient (CuDef) rats. Weanling male Sprague Dawley rats were fed a CuDef or CuAdeq diet ad libitum and given deionized water to drink. After 5 weeks on the diets, rats were assigned to one of four treatment regimens: Furo, Am or Furo + Am. Rats were anesthetized and electrolyte excretion was measured in 2 {times} 15 min control periods followed by 3 {times} 15 min treatment periods. Furo increased Na excretion in a dose dependent manner in both the CuAdeq and the CuDef rats. The response of the CuAdeq rats was slightly greater than that of the CuDef rats in each of the 3 treatment groups in which Furo was given. K excretion following Furo increased to the same extent in the CuAdeq and CuDef rats. The natriuretic response to Am alone was slightly greater in the CuDef than the CuAdeq rats. The antikaliuretic response of the CuDef rats was similar to that of the CuAdeq rats whether Am was given alone or in combination with Furo. These data show that CuDef rats respond to Furo and Am in a manner which is similar to that of CuAdeq rats, this indicates that the sensitivity of the Na reabsorption mechanisms to inhibition by diuretics is not markedly affected by copper deficiency.

Effects of renal denervation on tubular sodium handling in rats with CBL-induced liver cirrhosis

DEFF Research Database (Denmark)

Jonassen, T.E.; Brond, L.; Torp, M.

2003-01-01

This study was designed to examine the effect of bilateral renal denervation (DNX) on thick ascending limb of Henle's loop (TAL) function in rats with liver cirrhosis induced by common bile duct ligation (CBL). The CBL rats had, as previously shown, sodium retention associated with hypertrophy...... renal sympathetic nerve activity known to be present in CBL rats plays a significant role in the formation of sodium retention by stimulating sodium reabsorption in the TAL via increased renal abundance of NKCC2....

Recombinant erythropoietin acutely decreases renal perfusion and decouples the renin-angiotensin-aldosterone system.

Science.gov (United States)

Aachmann-Andersen, Niels J; Christensen, Soren J; Lisbjerg, Kristian; Oturai, Peter; Johansson, Pär I; Holstein-Rathlou, Niels-Henrik; Olsen, Niels V

2018-03-01

The effect of recombinant erythropoietin (rhEPO) on renal and systemic hemodynamics was evaluated in a randomized double-blinded, cross-over study. Sixteen healthy subjects were tested with placebo, or low-dose rhEPO for 2 weeks, or high-dose rhEPO for 3 days. Subjects refrained from excessive salt intake, according to instructions from a dietitian. Renal clearance studies were done for measurements of renal plasma flow, glomerular filtration rate (GFR) and the segmentel tubular handling of sodium and water (lithium clearance). rhEPO increased arterial blood pressure, total peripheral resistance, and renal vascular resistance, and decreased renal plasma flow in the high-dose rhEPO intervention and tended to decrease GFR. In spite of the decrease in renal perfusion, rhEPO tended to decrease reabsorption of sodium and water in the proximal tubule and induced a prompt decrease in circulating levels of renin and aldosterone, independent of changes in red blood cell mass, blood volumes, and blood pressure. We also found changes in biomarkers showing evidence that rhEPO induced a prothrombotic state. Our results suggest that rhEPO causes a direct downregulation in proximal tubular reabsorption that seems to decouple the activity of the renin-angiotensin-aldosterone system from changes in renal hemodynamics. This may serve as a negative feed-back mechanism on endogenous synthesis of EPO when circulating levels of EPO are high. These results demonstrates for the first time in humans a direct effect of rhEPO on renal hemodynamics and a decoupling of the renin-angiotensin-aldosterone system. © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Demeclocycline Attenuates Hyponatremia by Reducing Aquaporin-2 Expression in the Renal Inner Medulla

DEFF Research Database (Denmark)

Kortenoeven, Marleen L. A.; Sinke, Anne P.; Hadrup, Niels

2013-01-01

Binding of vasopressin to its type-2 receptor in renal collecting ducts induces cAMP signaling, transcription and translocation of aquaporin-2 (AQP2) water channels to the plasma membrane and water reabsorption from the pro-urine. Demeclocycline is currently used to treat hyponatremia in patients...

Effects of hyperventilation and hypocapnic/normocapnic hypoxemia on renal function and lithium clearance in humans

DEFF Research Database (Denmark)

Christensen, H; Klausen, T; Fogh-Andersen, N

1998-01-01

Using the renal clearance of lithium as an index of proximal tubular outflow, this study tested the hypothesis that acute hypocapnic hypoxemia decreases proximal tubular reabsorption to the same extent as hypocapnic normoxemia (hyperventilation) and that this response is blunted during normocapnic...

Effect of Cuscuta chinensis on renal function in ischemia/reperfusion-induced acute renal failure rats.

Science.gov (United States)

Shin, Sun; Lee, Yun Jung; Kim, Eun Ju; Lee, An Sook; Kang, Dae Gill; Lee, Ho Sub

2011-01-01

The kidneys play a central role in regulating water, ion composition and excretion of metabolic waste products in the urine. Cuscuta chinensis has been known as an important traditional Oriental medicine for the treatment of liver and kidney disorders. Thus, we studied whether an aqueous extract of Cuscuta chinensis (ACC) seeds has an effect on renal function parameters in ischemia/reperfusion-induced acute renal failure (ARF) rats. Administration of 250 mg/kg/day ACC showed that renal functional parameters including urinary excretion rate, osmolality, Na(+), K(+), Cl(-), creatinine clearance, solute-free water reabsorption were significantly recovered in ischemia/reperfusion-induced ARF. Periodic acid Schiff staining showed that administration of ACC improved tubular damage in ischemia/reperfusion-induced ARF. In immunoblot and immunohistological examinations, ischemia/reperfusion-induced ARF decreased the expressions of water channel AQP 2, 3 and sodium potassium pump Na,K-ATPase in the renal medulla. However, administration of ACC markedly incremented AQP 2, 3 and Na,K-ATPase expressions. Therefore, these data indicate that administration of ACC ameliorates regulation of the urine concentration and renal functions in rats with ischemia/reperfusion-induced ARF.

Distribution of glucose transporters in renal diseases

OpenAIRE

Szablewski, Leszek

2017-01-01

Kidneys play an important role in glucose homeostasis. Renal gluconeogenesis prevents hypoglycemia by releasing glucose into the blood stream. Glucose homeostasis is also due, in part, to reabsorption and excretion of hexose in the kidney. Lipid bilayer of plasma membrane is impermeable for glucose, which is hydrophilic and soluble in water. Therefore, transport of glucose across the plasma membrane depends on carrier proteins expressed in the plasma membrane. In humans, there are three famil...

Is nectar reabsorption restricted by the stalk cells of floral and extrafloral nectary trichomes?

Science.gov (United States)

Cardoso-Gustavson, P; Davis, A R

2015-01-01

Reabsorption is a phase of nectar dynamics that occurs concurrently with secretion; it has been described in floral nectaries that exude nectar through stomata or unicellular trichomes, but has not yet been recorded in extrafloral glands. Apparently, nectar reabsorption does not occur in multicellular secretory trichomes (MST) due to the presence of lipophilic impregnations - which resemble Casparian strips - in the anticlinal walls of the stalk cells. It has been assumed that these impregnations restrict solute movement within MST to occur unidirectionally and exclusively by the symplast, thereby preventing nectar reflux toward the underlying nectary tissues. We hypothesised that reabsorption is absent in nectaries possessing MST. The fluorochrome lucifer yellow (LYCH) was applied to standing nectar of two floral and extrafloral glands of distantly related species, and then emission spectra from nectary sections were systematically analysed using confocal microscopy. Passive uptake of LYCH via the stalk cells to the nectary tissues occurred in all MST examined. Moreover, we present evidence of nectar reabsorption in extrafloral nectaries, demonstrating that LYCH passed the stalk cells of MST, although it did not reach the deepest nectary tissues. Identical (control) experiments performed with neutral red (NR) demonstrated no uptake of this stain by actively secreting MST, whereas diffusion of NR did occur in plasmolysed MST of floral nectaries at the post-secretory phase, indicating that nectar reabsorption by MST is governed by stalk cell physiology. Interestingly, non-secretory trichomes failed to reabsorb nectar. The role of various nectary components is discussed in relation to the control of nectar reabsorption by secretory trichomes. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

Nutritional status, functional capacity and exercise rehabilitation in end-stage renal disease.

Science.gov (United States)

Mercer, T H; Koufaki, P; Naish, P F

2004-05-01

A significant percentage of patients with end-stage renal disease are malnourished and/or muscle wasted. Uremia is associated with decreased protein synthesis and increased protein degradation. Fortunately, nutritional status has been shown to be a modifiable risk factor in the dialysis population. It has long been proposed that exercise could positively alter the protein synthesis-degradation balance. Resistance training had been considered as the only form of exercise likely to induce anabolism in renal failure patients. However, a small, but growing, body of evidence indicates that for some dialysis patients, favourable improvements in muscle atrophy and fibre hypertrophy can be achieved via predominantly aerobic exercise training. Moreover, some studies tentatively suggest that nutritional status, as measured by SGA, can also be modestly improved by modes and patterns of exercise training that have been shown to also increase muscle fibre cross-sectional area and improve functional capacity. Functional capacity tests can augment the information content of basic nutritional status assessments of dialysis patients and as such are recommended for routine inclusion as a feature of all nutritional status assessments.

Increased Milk Protein Concentration in a Rehydration Drink Enhances Fluid Retention Caused by Water Reabsorption in Rats.

Science.gov (United States)

Ito, Kentaro; Saito, Yuri; Ashida, Kinya; Yamaji, Taketo; Itoh, Hiroyuki; Oda, Munehiro

2015-01-01

A fluid-retention effect is required for beverages that are designed to prevent dehydration. That is, fluid absorbed from the intestines should not be excreted quickly; long-term retention is desirable. Here, we focused on the effect of milk protein on fluid retention, and propose a new effective oral rehydration method that can be used daily for preventing dehydration. We first evaluated the effects of different concentrations of milk protein on fluid retention by measuring the urinary volumes of rats fed fluid containing milk protein at concentrations of 1, 5, and 10%. We next compared the fluid-retention effect of milk protein-enriched drink (MPD) with those of distilled water (DW) and a sports drink (SD) by the same method. Third, to investigate the mechanism of fluid retention, we measured plasma insulin changes in rats after ingesting these three drinks. We found that the addition of milk protein at 5 or 10% reduced urinary volume in a dose-dependent manner. Ingestion of the MPD containing 4.6% milk protein resulted in lower urinary volumes than DW and SD. MPD also showed a higher water reabsorption rate in the kidneys and higher concentrations of plasma insulin than DW and SD. These results suggest that increasing milk protein concentration in a beverage enhances fluid retention, which may allow the possibility to develop rehydration beverages that are more effective than SDs. In addition, insulin-modifying renal water reabsorption may contribute to the fluid-retention effect of MPD.

Nectar reabsorption and sugar translocation in male and female flowers of Cucurbita pepo

International Nuclear Information System (INIS)

Stpiczynska, M.; Nepi, M.

2005-01-01

Full text: The production and secretion of nectar has an energy cost that can be a substantial part of the energy economy of the plant. Plants may therefore recover part of the energy allocated to nectar secretion by reabsorbing nectar not collected by pollinators. This energy-saving strategy has been demonstrated by several authors by different methods. Here we demonstrate nectar reabsorption and sugar translocation in Cucurbita pepo by means of microautoradiography. Our results confirm that the dynamics of nectar reabsorption is different in male and female flowers. Differences in the dynamics of nectar reabsorption and sugar translocation were also found in pollinated and unpollinated female flowers. Pollinated female flowers reabsorbed sugar very quickly and translocated it to developing fruits in which ovules were the main sugar sink. Sugar translocation was slower and ovules did not label in unpollinated female flowers. (author)

Insulin resistance and hyperinsulinaemia in mild to moderate progressive chronic renal failure and its association with aerobic work capacity

DEFF Research Database (Denmark)

Eidemak, I; Feldt-Rasmussen, B; Kanstrup, I L

1995-01-01

Tissue sensitivity to insulin and aerobic work capacity was measured in patients with mild to moderate progressive chronic renal failure. Twenty-nine non-diabetic patients with a glomerular filtration rate of 25 ml.min-1.1.73 m-2 (11-43) (median, range) and 15 sex, age, and body mass index matched.......02) (M/I ratio 1.77 +/- 0.71 vs 2.57 +/- 0.70 (mg/(kgBW.min) per pmol/l.100, p aerobic work capacity was significantly lower in the patients than in the control subjects (24 +/- 8 vs 32 +/- 11 ml O2/(kg body weight.min), p .../I ratio in both groups. In conclusion, not only patients with end-stage chronic renal failure but also those with mild to moderate progressive chronic renal failure are insulin resistant and hyperinsulinaemic. The tissue sensitivity to insulin is correlated to the maximal aerobic work capacity suggesting...

Hemodynamic and renal implications of sodium-glucose cotransporter- 2 inhibitors in type 2 diabetes mellitus.

Science.gov (United States)

Tejedor Jorge, Alberto

2016-11-01

In DM2, there is increased expression of the proximal glucose transporter SGLT2. The increased glucose reabsorption from the urine to the proximal tubule and subsequently to the bloodstream, has three direct effects on the prognosis of patients with DM2: a) it increases the daily glucose load by raising the renal threshold for glucose, thus augmenting requirements for oral antidiabetics and insulin. This progressive increase occurs throughout the course of the disease and in parallel with the increase in renal mass (renal hypertrophy); b) because of the greater glucose reabsorption, glycosuria is lower than the level corresponding to glycaemia, decreasing the stimulus on the tubuloglomerular feedback system of the distal nephron. As a result, the glomerular vasodilation caused by hyperglycaemia is not arrested, maintaining glomerular hyperfiltration, and c) the excess glucose transported to the proximal tubular cells modifies their redox status, increasing local production of glycosylating products and activating local production of proinflammatory and profibrotic proliferative mediators. These mediators are responsible for the direct free radical damage to proximal tubular cells, for increased SGLT2 expression, increased production of collagen IV and extracellular matrix, and activation of monocyte/macrophages able to cause endothelial injury. The use of SGLT2 inhibitors not only reduces the reabsorption of glucose from the glomerular filtrate back into the circulationthus improving metabolic control in diabetesbut also restores tubuloglomerular feedback by increasing glycosuria and distal urinary flow. However, the most notable effect is due to inhibition of glucose entry to the proximal tubular cells. Glycosuria is toxic to the kidney: it harms glucosetransporting cells, that is, the proximal cells, which contain SGLT2. In animal models, SGLT2 inhibition reduces local production of oxygen-free radicals, the formation of mesangial matrix and collagen IV

Is the renal kallikrein-kinin system a factor that modulates hypercalciuria?

Directory of Open Access Journals (Sweden)

Armando Luis Negri

2017-01-01

Full Text Available Renal tubular calcium reabsorption is one of the principal factors that determine serum calcium concentration and calcium excretion. Calcium excretion is regulated by the distal convoluted tubule and connecting tubule, where the epithelial calcium channel TRPV5 can be found, which limits the rate of transcellular calcium transport. The dynamic presence of the TRPV5 channel on the surface of the tubular cell is mediated by an endosomal recycling process. Different intrarenal factors are involved in calcium channel fixation in the apical membrane, including the anti-ageing hormone klotho and tissue kallikrein (TK. Both proteins are synthesised in the distal tubule and secreted in the tubular fluid. TK stimulates active calcium reabsorption through the bradykinin receptor B2 that compromises TRPV5 activation through the protein kinase C pathway. TK-deficient mice show hypercalciuria of renal origin comparable to that seen in TRPV5 knockout mice. There is a polymorphism with loss of function of the human TK gene R53H (allele H that causes a marked decrease in enzymatic activity. The presence of the allele H seems to be common at least in the Japanese population (24%. These individuals have a tendency to greater calcium and sodium excretion in urine that is more evident during furosemide infusion. Future studies should analyse if manipulating the renal kallikrein-kinin system can correct idiopathic hypercalciuria with drugs other than thiazide diuretics.

Effects of positive end-expiratory pressure on renal function.

Science.gov (United States)

Järnberg, P O; de Villota, E D; Eklund, J; Granberg, P O

1978-01-01

The effects were studied positive end-expiratory pressure (PEEP) on renal function in eight patients with acute respiratory failure, requiring mechanical ventilation. On application of PEEP + 10 cm H2O, central venous pressure increased, systolic blood pressure decreased, urine flow and PAH-clearance were reduced, while inulin clearance remained stable. There was a marked increase in fractional sodium reabsorption and a concurrent decrease in fractional osmolal excretion. Fractional free-water clearance and the ratio UOsm/POsm did change.

Factors Influencing the Increase in Na-K-ATPase in Compensatory Renal Hypertrophy

Science.gov (United States)

Epstein, Franklin H.; Charney, Alan N.; Silva, Patricio

1978-01-01

An increase in Na-K-ATPase in kidney homogenates usually accompanies compensatory renal hypertrophy. While it may be evident in both the cortex and medulla of the kidney, it is most marked in the outer medulla and may be present only in that region. The increase in enzyme activity does not depend on an intact adrenal cortex and can be elicited in the absence of adrenal glucocorticoids. It is not seen in the form of renal hypertrophy produced by potassium depletion, in which the transport of sodium and potassium by the kidney is not increased. When present in compensatory renal growth, the enzyme change is correlated with an increase in the reabsorption of sodium, or the excretion of potassium, or both, per unit of renal tissue. It proceeds in the presence of either, but not in the absence of both. PMID:216164

Patterned dye structures limit reabsorption in luminescent solar concentrators

NARCIS (Netherlands)

Tsoi, S.; Broer, D.J.; Bastiaansen, C.W.M.; Debije, M.G.

2010-01-01

This work describes a method for limiting internal losses of a luminescent solar concentrator (LSC) due to reabsorption through patterning the fluorescent dye doped coating of the LSC. By engineering the dye coating into regular line patterns with fill factors ranging from 20 - 80%, the surface

Non-postural serial changes in renal function during the third trimester of normal human pregnancy.

Science.gov (United States)

Ezimokhai, M; Davison, J M; Philips, P R; Dunlop, W

1981-05-01

Seventeen healthy women were investigated near the beginning and again near the end of the third trimester of their normal pregnancies. Infusion studies were performed in the left lateral position. There was a highly significant decrease in effective renal plasma flow but not in glomerular filtration rate, measured as inulin clearance. Plasma creatinine concentration increased significantly, but the renal handling of creatinine was unchanged; simultaneous 24-hour creatinine clearance showed a tendency to decrease. Serum urate concentration also increased significantly, apparently due to an increase in net tubular reabsorption of urate.

Accurate determination of renal function in patients with intestinal urinary diversions

International Nuclear Information System (INIS)

McDougal, W.S.; Koch, M.O.

1986-01-01

The regular determination of renal function is a critical part of the management of patients who have had the urinary tract reconstructed with intestinal segments. These intestinal segments reabsorb urinary solutes and, thereby, complicate the determination of renal function by conventional methods. Urinary clearances of urea, creatinine and inulin were performed in patients with intestinal segments in the urinary tract and controls under varying diuretic conditions. Patients with intestinal diversions also underwent radioisotopic determination of renal function. The urinary clearances of urea, creatinine and inulin are highly dependent on the rate of urine flow in patients with intestinal segments in the urinary tract. Diuresis maximizes the urinary clearances of these solutes by minimizing intestinal reabsorption. Creatinine clearance prediction from the serum creatinine underestimates true glomerular filtration rate. Radioisotopic determination of renal function correlates poorly with true glomerular filtration rate. Only creatinine clearance measured under diuretic conditions correlates well with true renal function. Urine concentrating ability cannot be assessed accurately in patients with intestinal segments in the urinary tract, since osmolality rapidly equilibrates across the segments

Mineralocorticoid-induced sodium appetite and renal salt retention: Evidence for common signaling and effector mechanisms

Science.gov (United States)

Fu, Yiling; Vallon, Volker

2014-01-01

An increase in renal sodium chloride (salt) retention and an increase in sodium appetite is the body's response to salt restriction or depletion in order to restore salt balance. Renal salt retention and increased sodium appetite can also be maladaptive and sustain the pathophysiology in conditions like salt-sensitive hypertension and chronic heart failure. Here we review the central role of the mineralocorticoid aldosterone in both the increase in renal salt reabsorption and sodium appetite. We discuss the working hypothesis that aldosterone activates similar signaling and effector mechanisms in the kidney and brain, including the mineralocorticoid receptor, the serum-and-glucocorticoid-induced kinase SGK1, the ubiquitin ligase NEDD4-2, and the epithelial sodium channel ENaC. The latter also mediates the gustatory salt sensing in the tongue, which is required for the manifestation of increased salt intake. Effects of aldosterone on both brain and kidney synergize with the effects of angiotensin II. Thus, mineralocorticoids appear to induce similar molecular pathways in the kidney, brain, and possibly tongue, which could provide opportunities for more effective therapeutic interventions. Inhibition of renal salt reabsorption is compensated by stimulation of salt appetite and vice versa; targeting both mechanisms should be more effective. Inhibiting the arousal to consume salty food may improve a patient's compliance to reducing salt intake. While a better understanding of the molecular mechanisms is needed and will provide new options, current pharmacological interventions that target both salt retention and sodium appetite include mineralocorticoid receptor antagonists and potentially inhibitors of angiotensin II and ENaC. PMID:25376899

Renal hemodynamics and oxygenation in transient renal artery occluded rats evaluated with iron-oxide particles and oxygenation-sensitive imaging

International Nuclear Information System (INIS)

Pedersen, Michael; Aarhus Univ.; Univ. Victor Segalen Bordeaux 2; Laustsen, Christoffer; Perot, Vincent; Grenier, Nicolas; Basseau, Fabrice; Moonen, Chrit

2010-01-01

Mild or severe renal arterial occlusion is a phenomenon occasionally observed in daily clinical practice, potentially leading to renal ischemia and a general impairment of renal function. Secondly, closing the blood flow to the kidneys can also occur during kidney transplantation procedures. However, the exact physiological effects of these conditions on renal blood perfusion as well as the renal oxygen handling are poorly understood. The objectives of this study were therefore to measure the lateral changes of renal blood perfusion in rats subjected to transient unilateral arterial occlusion (RAS), and in addition, to measure the consequences on the intrarenal oxygenation. Experimental studies were performed using sixteen adolescent rats. The left renal artery was exposed through a flank incision and acute RAS for 45 min was achieved by placing a ligature around the renal artery. MRI was performed 3 days after the surgical procedure, where a blood oxygenation sensitive sequence (BOLD MRI) was performed, followed by a perfusion-weighted imaging sequence using a single bolus of the iron-oxide nanoparticle Sinerem. The renal oxygenation of blood was indirectly measured by the BOLD-parameter R2 * , and perfusion measures include relative renal blood flow, relative renal blood volume and mean transit time. Histopathologic changes through the outer stripe of the outer medulla showing typical histopathologic findings of ischemia. This study demonstrated that rats with transient renal arterial stenosis (for 45 min) showed a reduction in intrarenal oxygenation and intrarenal blood flow three days after the surgical procedure. A decreased R2 * was measured within the ipsilateral medulla in parallel with a decreased medullary blood flow, is probably related to a lower reabsorption load within the ipsilateral kidney. MRI may therefore be a promising tool in long-term evaluation of RAS. (orig.)

Renal hemodynamics and oxygenation in transient renal artery occluded rats evaluated with iron-oxide particles and oxygenation-sensitive imaging

Energy Technology Data Exchange (ETDEWEB)

Pedersen, Michael [Aarhus Univ. Hospital (Denmark). MR Research Centre; Aarhus Univ. (Denmark). Inst. of Experimental Clinical Medicine; Univ. Victor Segalen Bordeaux 2 (France). Lab. Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231; Laustsen, Christoffer [Aarhus Univ. Hospital (Denmark). MR Research Centre; Perot, Vincent; Grenier, Nicolas [Hopital Pellegrin, CHU Bordeaux (France). Service d' Imagerie Diagnostique et Therapeutique de l' Adulte; Basseau, Fabrice; Moonen, Chrit [Univ. Victor Segalen Bordeaux 2 (France). Lab. Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231

2010-07-01

Mild or severe renal arterial occlusion is a phenomenon occasionally observed in daily clinical practice, potentially leading to renal ischemia and a general impairment of renal function. Secondly, closing the blood flow to the kidneys can also occur during kidney transplantation procedures. However, the exact physiological effects of these conditions on renal blood perfusion as well as the renal oxygen handling are poorly understood. The objectives of this study were therefore to measure the lateral changes of renal blood perfusion in rats subjected to transient unilateral arterial occlusion (RAS), and in addition, to measure the consequences on the intrarenal oxygenation. Experimental studies were performed using sixteen adolescent rats. The left renal artery was exposed through a flank incision and acute RAS for 45 min was achieved by placing a ligature around the renal artery. MRI was performed 3 days after the surgical procedure, where a blood oxygenation sensitive sequence (BOLD MRI) was performed, followed by a perfusion-weighted imaging sequence using a single bolus of the iron-oxide nanoparticle Sinerem. The renal oxygenation of blood was indirectly measured by the BOLD-parameter R2{sup *}, and perfusion measures include relative renal blood flow, relative renal blood volume and mean transit time. Histopathologic changes through the outer stripe of the outer medulla showing typical histopathologic findings of ischemia. This study demonstrated that rats with transient renal arterial stenosis (for 45 min) showed a reduction in intrarenal oxygenation and intrarenal blood flow three days after the surgical procedure. A decreased R2{sup *} was measured within the ipsilateral medulla in parallel with a decreased medullary blood flow, is probably related to a lower reabsorption load within the ipsilateral kidney. MRI may therefore be a promising tool in long-term evaluation of RAS. (orig.)

Renal glucose metabolism in normal physiological conditions and in diabetes.

Science.gov (United States)

Alsahli, Mazen; Gerich, John E

2017-11-01

The kidney plays an important role in glucose homeostasis via gluconeogenesis, glucose utilization, and glucose reabsorption from the renal glomerular filtrate. After an overnight fast, 20-25% of glucose released into the circulation originates from the kidneys through gluconeogenesis. In this post-absorptive state, the kidneys utilize about 10% of all glucose utilized by the body. After glucose ingestion, renal gluconeogenesis increases and accounts for approximately 60% of endogenous glucose release in the postprandial period. Each day, the kidneys filter approximately 180g of glucose and virtually all of this is reabsorbed into the circulation. Hormones (most importantly insulin and catecholamines), substrates, enzymes, and glucose transporters are some of the various factors influencing the kidney's role. Patients with type 2 diabetes have an increased renal glucose uptake and release in the fasting and the post-prandial states. Additionally, glucosuria in these patients does not occur at plasma glucose levels that would normally produce glucosuria in healthy individuals. The major abnormality of renal glucose metabolism in type 1 diabetes appears to be impaired renal glucose release during hypoglycemia. Copyright © 2017 Elsevier B.V. All rights reserved.

Diminished renal urea excretion in the llama at reduced food intake

International Nuclear Information System (INIS)

Engelhardt, W.; Engelhardt, W. von

1976-01-01

Renal urea excretion was studied in three llamas under various feeding conditions. Glomerular filtration rate (GFR) was estimated from inulin clearance. Tubular reabsorbed urea was the difference between glomerular filtered and renal excreted urea. Plasma urea concentration increased significantly when feeding was reduced by 40% and 60%, not applicable to a straw diet. With reduced hay feeding and on a straw diet only a slight and insignificant decrease was observed in renal urea excretion, with only a 3% lowering in GFR and glomerular filtered urea. With a straw diet, the glomerular filtered urea was significantly below the controls. The fraction of filtered urea reabsorbed in the tubules was constant (36%-47%). Very high reabsorption (87%) on a supplemented straw dietwas observed in one llama which after nearly 6 months on this low protein diet - could be shown to have lost only 5% of its body weight

Reabsorption kinetics of albumin from pleural space of dogs

International Nuclear Information System (INIS)

Miniati, M.; Parker, J.C.; Pistolesi, M.; Cartledge, J.T.; Martin, D.J.; Giuntini, C.; Taylor, A.E.

1988-01-01

The reabsorption of albumin from the pleural space was measured in eight dogs receiving 0.5 ml intrapleural injection of 131 I-labeled albumin and a simultaneous intravenous injection of 125 I-labeled albumin. Plasma curves for both tracers were obtained over 24 h. The 125 I-albumin curve served as input function of albumin for interstitial spaces, including pleura, whereas the 131 I-albumin curve represented the output function from pleural space. The frequency function of albumin transit times from pleural space to plasma was obtained by deconvolution of input-output plasma curves. Plasma recovery of 131 I-albumin was complete by 24 h, and the mean transit time from pleura to plasma averaged 7.95 +/- 1.57 (SD) h. Albumin reabsorption occurred mainly via lymphatics as indicated by experiments in 16 additional dogs in which their right lymph ducts or thoracic ducts were ligated before intrapleural injection. A pleural lymph flow of 0.020 +/- 0.003 (SD) ml.kg-1.h-1 was estimated, which is balanced by a comparable filtration of fluid into the pleural space. This suggests that, under physiological conditions, the subpleural lymphatics represent an important control mechanism of pleural liquid pressure

Microinjection studies of phosphate permeability in rats during mild saline diuresis: influence of acute thyroparathyroidectomy and parathormone administration

International Nuclear Information System (INIS)

Poujeol, P.; Rouffignac, C. de.

1975-01-01

The tubular permeability to phosphate of the different segments of the rat nephron and the influence of parathyroid hormone on such a permeability were investigated. Tracer microinjections of 32 P and 3 H inulin were performed in control, acutely thyroparathyroidectomized (TPTX) and TPTX + PTH animals undergoing saline diuresis. In order to estimate the 32 P reabsorption capacity of the proximal convoluted tubule (PCT), the loop of Henle and the terminal part of the nephron, microinjections were performed in early proximal, late proximal and early distal tubules respectively. The results reported confirm that the renal phosphate reabsorption is under PTH control [fr

The plasma carnitine concentration regulates renal OCTN2 expression and carnitine transport in rats

OpenAIRE

Schürch, R; Todesco, L; Novakova, K; Mevissen, M; Stieger, B; Krähenbühl, S

2010-01-01

Previous findings in rats and in human vegetarians suggest that the plasma carnitine concentration and/or carnitine ingestion may influence the renal reabsorption of carnitine. We tested this hypothesis in rats with secondary carnitine deficiency following treatment with N-trimethyl-hydrazine-3-propionate (THP) for 2 weeks and rats treated with excess L-carnitine for 2 weeks. Compared to untreated control rats, treatment with THP was associated with an approximately 70% decrease in plasma car...

The influence of angiotensin-converting enzyme inhibition on renal tubular function in progressive chronic nephropathy

DEFF Research Database (Denmark)

Kamper, A L; Holstein-Rathlou, N H; Leyssac, P P

1996-01-01

The influence of angiotensin-converting enzyme (ACE) inhibition on renal tubular function in progressive chronic nephropathy was investigated in 69 patients by the lithium clearance (C(Li)) method. Studies were done repeatedly for up to 2 years during a controlled trial on the effect of enalapril...... on progression of renal failure. The pattern of proteinuria was followed over the first 9 months. At baseline, the glomerular filtration rate (GFR) was 5 to 68 mL/min. Absolute proximal tubular reabsorption rate of fluid (APR), estimated as the difference between GFR and C(Li), was 1 to 54 mL/min. Calculated...... in either treatment regimen was associated with a long-term slower progression of renal failure. Over 9 months, the 24-hour fractional clearance of albumin decreased in the ACE inhibitor group (P

The Association of Albuminuria With Tubular Reabsorption of Uric Acid: Results From a General Population Cohort

Science.gov (United States)

Scheven, Lieneke; Joosten, Michel M.; de Jong, Paul E.; Bakker, Stephan J. L.; Gansevoort, Ron T.

2014-01-01

Background Elevated albuminuria as well as an increased serum uric acid concentration is associated with poor cardiovascular outcome. We questioned whether these 2 variables (albuminuria and serum uric concentration) may be interrelated via tubular uric acid reabsorption. Methods and Results Included were 7688 participants of the PREVEND Study, an observational, general population‐based cohort study. Linear regression analyses were used to test associations of baseline albuminuria with baseline serum uric acid concentration and tubular uric acid reabsorption (calculated as [100−fractional uric acid excretion]%). Cox regression analyses were used to study the association of baseline serum uric acid and albuminuria with incident cardiovascular morbidity and mortality. In cross‐sectional analyses, albuminuria was associated positively with serum uric acid concentration, both crude and after adjustment for potential confounders (both Puric acid reabsorption, again both crude and after adjustment for potential confounders (both Puric acid were associated with incident cardiovascular events (Hazard Ratios 1.09 [1.03 to 1.17], P=0.01 and 1.19 [1.09 to 1.30], Puric acid being less predictive for cardiovascular morbidity and mortality in the presence of high albuminuria and vice versa. Conclusions Albuminuria is strongly associated with tubular uric acid reabsorption, and consequently with serum uric acid concentration. This phenomenon may explain in part why albuminuria is associated with cardiovascular outcome. PMID:24772520

Evaluation of oxidative stress status and antioxidant capacity in patients with renal cell carcinoma

OpenAIRE

Aldemir, Mustafa; Karaguzel, Ersagun; Okulu, Emrah; Gudeloglu, Ahmet; Ener, Kemal; Ozayar, Asim; Erel, Ozcan

2015-01-01

Introduction We evaluated and compared the serum oxidative stress and antioxidant enzymes in patients with renal cell carcinoma (RCC) and the control group. Material and methods The prospective study consisted of 97 patients with RCC (Group 1) and 80 age and sex matched healthy volunteers (Group 2). Group 1 and 2 were compared concerning serum mean total oxidant status (TOS), total antioxidant capacity (TAC), paraoxonase-1 (PON-1), arylesterase, total thiol, catalase (CAT), myeloperoxidase (M...

SGLT2 Inhibitors: Glucotoxicity and Tumorigenesis Downstream the Renal Proximal Tubule?

Science.gov (United States)

Bertinat, Romina; Nualart, Francisco; Yáñez, Alejandro J

2016-08-01

At present, diabetes mellitus is the main cause of end-stage renal disease. Effective glycaemic management is the most powerful tool to delay the establishment of diabetic complications, such as diabetic kidney disease. Together with reducing blood glucose levels, new anti-diabetic agents are expected not only to control the progression but also to restore known defects of the diabetic kidney. Sodium-glucose co-transporter 2 (SGLT2) inhibitors are promising anti-diabetic agents that reduce hyperglycaemia by impairing glucose reabsorption in proximal tubule of the kidney and increasing glucosuria. SGLT2 inhibitors have shown to reduce glucotoxicity in isolated proximal tubule cells and also to attenuate expression of markers of overall kidney damage in experimental animal models of diabetes, but the actual renoprotective effect for downstream nephron segments is still unknown and deserves further attention. Here, we briefly discuss possible undesired effects of enhanced glucosuria and albuminuria in nephron segments beyond the proximal tubule after SGLT2 inhibitor treatment, offering new lines of research to further understand the renoprotective action of these anti-diabetic agents. Strategies blocking glucose reabsorption by renal proximal tubule epithelial cells (RPTEC) may be protective for RPTEC, but downstream nephron segments will still be exposed to high glucose and albumin levels through the luminal face. The actual effect of constant enhanced glucosuria over distal nephron segments remains to be established. J. Cell. Physiol. 231: 1635-1637, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Role of the Sympathetic Nervous System and Its Modulation in Renal Hypertension.

Science.gov (United States)

Sata, Yusuke; Head, Geoffrey A; Denton, Kate; May, Clive N; Schlaich, Markus P

2018-01-01

The kidneys are densely innervated with renal efferent and afferent nerves to communicate with the central nervous system. Innervation of major structural components of the kidneys, such as blood vessels, tubules, the pelvis, and glomeruli, forms a bidirectional neural network to relay sensory and sympathetic signals to and from the brain. Renal efferent nerves regulate renal blood flow, glomerular filtration rate, tubular reabsorption of sodium and water, as well as release of renin and prostaglandins, all of which contribute to cardiovascular and renal regulation. Renal afferent nerves complete the feedback loop via central autonomic nuclei where the signals are integrated and modulate central sympathetic outflow; thus both types of nerves form integral parts of the self-regulated renorenal reflex loop. Renal sympathetic nerve activity (RSNA) is commonly increased in pathophysiological conditions such as hypertension and chronic- and end-stage renal disease. Increased RSNA raises blood pressure and can contribute to the deterioration of renal function. Attempts have been made to eliminate or interfere with this important link between the brain and the kidneys as a neuromodulatory treatment for these conditions. Catheter-based renal sympathetic denervation has been successfully applied in patients with resistant hypertension and was associated with significant falls in blood pressure and renal protection in most studies performed. The focus of this review is the neural contribution to the control of renal and cardiovascular hemodynamics and renal function in the setting of hypertension and chronic kidney disease, as well as the specific roles of renal efferent and afferent nerves in this scenario and their utility as a therapeutic target.

Kidney protection during peptide receptor radionuclide therapy with somatostatin analogues

Energy Technology Data Exchange (ETDEWEB)

Rolleman, Edgar J.; Melis, Marleen; Valkema, Roelf; Krenning, Eric P.; Jong, Marion de [Erasmus MC, Department of Nuclear Medicine, V 220, Rotterdam (Netherlands); Boerman, Otto C. [Radboud University Hospital, Department of Nuclear Medicine, Nijmegen (Netherlands)

2010-05-15

This review focuses on the present status of kidney protection during peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues. This treatment modality for somatostatin receptor-positive tumours is limited by renal reabsorption and retention of radiolabelled peptides resulting in dose-limiting high kidney radiation doses. Radiation nephropathy has been described in several patients. Studies on the mechanism and localization demonstrate that renal uptake of radiolabelled somatostatin analogues largely depends on the megalin/cubulin system in the proximal tubule cells. Thus methods are needed that interfere with this reabsorption pathway to achieve kidney protection. Such methods include coadministration of basic amino acids, the bovine gelatin-containing solution Gelofusine or albumin fragments. Amino acids are already commonly used in the clinical setting during PRRT. Other compounds that interfere with renal reabsorption capacity (maleic acid and colchicine) are not suitable for clinical use because of potential toxicity. The safe limit for the renal radiation dose during PRRT is not exactly known. Dosimetry studies applying the principle of the biological equivalent dose (correcting for the effect of dose fractionation) suggest that a dose of about 37 Gy is the threshold for development of kidney toxicity. This threshold is lower when risk factors for development of renal damage exist: age over 60 years, hypertension, diabetes mellitus and previous chemotherapy. A still experimental pathway for kidney protection is mitigation of radiation effects, possibly achievable by cotreatment with amifostine (Ethylol), a radiation protector, or with blockers of the renin-angiotensin-aldosterone system. Future perspectives on improving kidney protection during PRRT include combinations of agents to reduce renal retention of radiolabelled peptides, eventually together with mitigating medicines. Moreover, new somatostatin analogues with lower

Kidney protection during peptide receptor radionuclide therapy with somatostatin analogues

International Nuclear Information System (INIS)

Rolleman, Edgar J.; Melis, Marleen; Valkema, Roelf; Krenning, Eric P.; Jong, Marion de; Boerman, Otto C.

2010-01-01

This review focuses on the present status of kidney protection during peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues. This treatment modality for somatostatin receptor-positive tumours is limited by renal reabsorption and retention of radiolabelled peptides resulting in dose-limiting high kidney radiation doses. Radiation nephropathy has been described in several patients. Studies on the mechanism and localization demonstrate that renal uptake of radiolabelled somatostatin analogues largely depends on the megalin/cubulin system in the proximal tubule cells. Thus methods are needed that interfere with this reabsorption pathway to achieve kidney protection. Such methods include coadministration of basic amino acids, the bovine gelatin-containing solution Gelofusine or albumin fragments. Amino acids are already commonly used in the clinical setting during PRRT. Other compounds that interfere with renal reabsorption capacity (maleic acid and colchicine) are not suitable for clinical use because of potential toxicity. The safe limit for the renal radiation dose during PRRT is not exactly known. Dosimetry studies applying the principle of the biological equivalent dose (correcting for the effect of dose fractionation) suggest that a dose of about 37 Gy is the threshold for development of kidney toxicity. This threshold is lower when risk factors for development of renal damage exist: age over 60 years, hypertension, diabetes mellitus and previous chemotherapy. A still experimental pathway for kidney protection is mitigation of radiation effects, possibly achievable by cotreatment with amifostine (Ethylol), a radiation protector, or with blockers of the renin-angiotensin-aldosterone system. Future perspectives on improving kidney protection during PRRT include combinations of agents to reduce renal retention of radiolabelled peptides, eventually together with mitigating medicines. Moreover, new somatostatin analogues with lower

Recombinant human erythropoietin in humans down-regulates proximal renal tubular reabsorption and causes a fall in glomerular filtration rate

DEFF Research Database (Denmark)

Olsen, Niels Vidiendal; Aachmann-Andersen, Niels Jacob; Oturai, Peter

2010-01-01

HuEPO for 28 days in doses raising the hematocrit to 48.3 (4.1) %. Renal clearance studies with urine collections (N = 8) were done at baseline and at days 4, 11, 29, and 42. Glomerular filtration rate (GFR) was measured by (51)Cr-EDTA. Renal clearance of lithium (C(Li)) was used as an index of proximal...... tubular outflow and to assess segmental renal tubular handling of sodium and water. rHuEPO-induced increases in hematocrit occurred from day 10 onwards and was caused by both an increase in red cell volume and a fall in plasma volume. Well before that (from day 2 and throughout the treatment time), r...... and water (APR = GFR - C(Li), P

Renal Cu and Na excretion and hepatic Cu metabolism in both Cu acclimated and non acclimated rainbow trout (Oncorhynchus mykiss)

DEFF Research Database (Denmark)

Grosell, M.; Hogstrand, C.; Wood, C.M.

1998-01-01

protein depending on whether the Cu is derived from recent branchial uptake or is already present in the plasma prior to Cu-64 exposure. The plasma Cu pool derived from recent branchial uptake and the Cu pool present in the plasma prior to Cu-64 exposure is accessible to renal excretion to different...... Na+ efflux decreased by 40%, which was largely due to increased tubular Na+ reabsorption. Renal compensation for the impaired branchial Na+ uptake, seen during Cu exposure, thus seems to be involved in Cu acclimation in rainbow trout. (C) 1998 Elsevier Science B.V....

Urinary Excretion of Tetrodotoxin Modeled in a Porcine Renal Proximal Tubule Epithelial Cell Line, LLC-PK1

Directory of Open Access Journals (Sweden)

Takuya Matsumoto

2017-07-01

Full Text Available This study examined the urinary excretion of tetrodotoxin (TTX modeled in a porcine renal proximal tubule epithelial cell line, LLC-PK1. Time course profiles of TTX excretion and reabsorption across the cell monolayers at 37 °C showed that the amount of TTX transported increased linearly for 60 min. However, at 4 °C, the amount of TTX transported was approximately 20% of the value at 37 °C. These results indicate that TTX transport is both a transcellular and carrier-mediated process. Using a transport inhibition assay in which cell monolayers were incubated with 50 µM TTX and 5 mM of a transport inhibitor at 37 °C for 30 min, urinary excretion was significantly reduced by probenecid, tetraethylammonium (TEA, l-carnitine, and cimetidine, slightly reduced by p-aminohippuric acid (PAH, and unaffected by 1-methyl-4-phenylpyridinium (MPP+, oxaliplatin, and cefalexin. Renal reabsorption was significantly reduced by PAH, but was unaffected by probenecid, TEA and l-carnitine. These findings indicate that TTX is primarily excreted by organic cation transporters (OCTs and organic cation/carnitine transporters (OCTNs, partially transported by organic anion transporters (OATs and multidrug resistance-associated proteins (MRPs, and negligibly transported by multidrug and toxic compound extrusion transporters (MATEs.

Renal morphology of Bradypus torquatus

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Pedro Kastein Faria da Cunha Bianchi

2012-11-01

Full Text Available Among the Xenarthras, sloths present a hydric ingestion restricted to water from leaves, fruits, and vegetables. As a first approach to verify whether these animals have some morphophysiological difference which could justify or compensate this low hydric ingestion, the renal anatomy of these animals was investigated, particularly that of maned sloth (Bradypus torquatus. Kidneys from these animals were macroscopically analyzed, through light microscopy and scanning electron microscopy. The Bradypus torquatus kidneys are bean-shaped paired organs, located dorso-cranially to the pelvic girdle, between the peritoneum and the posterior abdominal wall. The use of histological techniques allowed us to identify, in the cortical region, the renal corpuscles and tubules, and, in the medullary region, a significant amount of interstitial tissue with a collecting duct. The results of this study showed that, although Bradypus torquatus doesn’t drink water directly, its kidneys doesn’t differ from that of most mammals, presenting the same anatomical structure, suggesting that these animals fully reach their hydric needs, basically by consuming leaves, fruits, and sprouts. Nevertheless, in order to confirm this hypothesis, studies on the effectiveness of water reabsorption, such as the renin-angiotensin-aldosterone system, must be carried out.

Effects of acute hypoxia on renal and endocrine function at rest and during graded exercise in hydrated subjects

DEFF Research Database (Denmark)

Olsen, Niels Vidiendal; Kanstrup, I L; Richalet, J P

1992-01-01

Renal effects of altitude hypoxia are unclear. Renal and hormonal function was investigated in eight males at rest and during graded exercise at sea level (SL) and 48 h after rapid ascent to 4,350 m (HA). HA did not change resting values of effective renal plasma flow (ERPF), glomerular filtration...... rate (GFR), sodium clearance (CNa), urine flow, or lithium clearance (CLi), which was used as an index of proximal tubular outflow. At rest, HA increased plasma norepinephrine concentration and decreased plasma concentrations of renin and aldosterone. Exercise decreased ERPF similarly in both...... environments. Normoxic exercise progressively reduced GFR, but at HA GFR only decreased during heavy exercise. This resulted in a higher filtration fraction during light and moderate hypoxic exercise. However, calculated absolute proximal reabsorption rate (GFR-CLi) at HA was higher during low...

Role of the Sympathetic Nervous System and Its Modulation in Renal Hypertension

Directory of Open Access Journals (Sweden)

Yusuke Sata

2018-03-01

Full Text Available The kidneys are densely innervated with renal efferent and afferent nerves to communicate with the central nervous system. Innervation of major structural components of the kidneys, such as blood vessels, tubules, the pelvis, and glomeruli, forms a bidirectional neural network to relay sensory and sympathetic signals to and from the brain. Renal efferent nerves regulate renal blood flow, glomerular filtration rate, tubular reabsorption of sodium and water, as well as release of renin and prostaglandins, all of which contribute to cardiovascular and renal regulation. Renal afferent nerves complete the feedback loop via central autonomic nuclei where the signals are integrated and modulate central sympathetic outflow; thus both types of nerves form integral parts of the self-regulated renorenal reflex loop. Renal sympathetic nerve activity (RSNA is commonly increased in pathophysiological conditions such as hypertension and chronic- and end-stage renal disease. Increased RSNA raises blood pressure and can contribute to the deterioration of renal function. Attempts have been made to eliminate or interfere with this important link between the brain and the kidneys as a neuromodulatory treatment for these conditions. Catheter-based renal sympathetic denervation has been successfully applied in patients with resistant hypertension and was associated with significant falls in blood pressure and renal protection in most studies performed. The focus of this review is the neural contribution to the control of renal and cardiovascular hemodynamics and renal function in the setting of hypertension and chronic kidney disease, as well as the specific roles of renal efferent and afferent nerves in this scenario and their utility as a therapeutic target.

Renal handling of technetium-99m DMSA: Evidence for glomerular filtration and peritubular uptake

International Nuclear Information System (INIS)

de Lange, M.J.; Piers, D.A.; Kosterink, J.G.; van Luijk, W.H.; Meijer, S.; de Zeeuw, D.; van der Hem, G.K.

1989-01-01

The finding of an enhanced excretion of [ 99m Tc]dimercaptosuccinic acid (DMSA) in patients with tubular reabsorption disorders prompted us to investigate the role of filtration in the renal handling of [ 99m Tc]DMSA. Our studies in human serum indicated that binding to serum proteins was approximately 90%. Chromatography of human urine and studies in rats showed that the complex was excreted unaltered into the urine. Renal extraction of [ 99m Tc]DMSA in a human volunteer was 5.8%. Continuous infusion of [ 99m Tc]DMSA in 13 individuals with normal renal function gave the following results (mean +/- s.d.): plasma clearance of [ 99m Tc]DMSA 34 +/- 4 ml/min, urinary clearance of [ 99m Tc]DMSA 12 +/- 3 ml/min. The calculated filtered load of [ 99m Tc]DMSA closely resembled the urinary clearance, whereas the plasma clearance was about three times faster. This indicates that peritubular uptake accounts for approximately 65% and filtration for approximately 35% of the renal handling of [ 99m Tc]DMSA

Mini-review: regulation of the renal NaCl cotransporter by hormones.

Science.gov (United States)

Rojas-Vega, Lorena; Gamba, Gerardo

2016-01-01

The renal thiazide-sensitive NaCl cotransporter, NCC, is the major pathway for salt reabsorption in the distal convoluted tubule. The activity of this cotransporter is critical for regulation of several physiological variables such as blood pressure, serum potassium, acid base metabolism, and urinary calcium excretion. Therefore, it is not surprising that numerous hormone-signaling pathways regulate NCC activity to maintain homeostasis. In this review, we will provide an overview of the most recent evidence on NCC modulation by aldosterone, angiotensin II, vasopressin, glucocorticoids, insulin, norepinephrine, estradiol, progesterone, prolactin, and parathyroid hormone. Copyright © 2016 the American Physiological Society.

Metabolic and hemodynamic effects of sodium-dependent glucose cotransporter 2 inhibitors on cardio-renal protection in the treatment of patients with type 2 diabetes mellitus.

Science.gov (United States)

Kashiwagi, Atsunori; Maegawa, Hiroshi

2017-07-01

The specific sodium-glucose cotransporter 2 inhibitors (SGLT2 inhibitors) inhibit glucose reabsorption in proximal renal tubular cells, and both fasting and postprandial glucose significantly decrease because of urinary glucose loss. As a result, pancreatic β-cell function and peripheral insulin action significantly improve with relief from glucose toxicity. Furthermore, whole-body energy metabolism changes to relative glucose deficiency and triggers increased lipolysis in fat cells, and fatty acid oxidation and then ketone body production in the liver during treatment with SGLT2 inhibitors. In addition, SGLT2 inhibitors have profound hemodynamic effects including diuresis, dehydration, weight loss and lowering blood pressure. The most recent findings on SGLT2 inhibitors come from results of the Empagliflozin, Cardiovascular Outcomes and Mortality in Type 2 Diabetes trial. SGLT2 inhibitors exert extremely unique and cardio-renal protection through metabolic and hemodynamic effects, with long-term durability on the reduction of blood glucose, bodyweight and blood pressure. Although a site of action of SGLT2 inhibitors is highly specific to inhibit renal glucose reabsorption, whole-body energy metabolism, and hemodynamic and renal functions are profoundly modulated during the treatment of SGLT2 inhibitors. Previous studies suggest multifactorial clinical benefits and safety concerns of SGLT2 inhibitors. Although ambivalent clinical results of this drug are still under active discussion, the present review summarizes promising recent evidence on the cardio-renal and metabolic benefits of SGLT2 inhibitors in the treatment of type 2 diabetes. © 2017 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

OBESITY-INDUCED HYPERTENSION: INTERACTION OF NEUROHUMORAL AND RENAL MECHANISMS

Science.gov (United States)

Hall, John E.; do Carmo, Jussara M.; da Silva, Alexandre A.; Wang, Zhen; Hall, Michael E.

2015-01-01

Excess weight gain, especially when associated with increased visceral adiposity, is a major cause of hypertension, accounting for 65–75% of the risk for human primary (essential) hypertension. Increased renal tubular sodium reabsorption impairs pressure natriuresis and plays an important role in initiating obesity hypertension. The mediators of abnormal kidney function and increased blood pressure during development of obesity hypertension include 1) physical compression of the kidneys by fat in and around the kidneys, 2) activation of the renin-angiotensin-aldosterone system (RAAS), and 3) increased sympathetic nervous system (SNS) activity. Activation of the RAAS system is likely due, in part, to renal compression as well as SNS activation. However, obesity also causes mineralocorticoid receptor activation independent of aldosterone or angiotensin II. The mechanisms for SNS activation in obesity have not been fully elucidated but appear to require leptin and activation of the brain melanocortin system. With prolonged obesity and development of target organ injury, especially renal injury, obesity-associated hypertension becomes more difficult to control, often requiring multiple antihypertensive drugs and treatment of other risk factors, including dyslipidemia, insulin resistance and diabetes, and inflammation. Unless effective anti-obesity drugs are developed, the impact of obesity on hypertension and related cardiovascular, renal and metabolic disorders is likely to become even more important in the future as the prevalence of obesity continues to increase. PMID:25767285

Receptor-mediated endocytosis of lysozyme in renal proximal tubules of the frog Rana temporaria

Directory of Open Access Journals (Sweden)

E.V. Seliverstova

2015-04-01

Full Text Available The mechanism of protein reabsorption in the kidney of lower vertebrates remains insufficiently investigated in spite of raising interest to the amphibian and fish kidneys as a useful model for physiological and pathophysiological examinations. In the present study, we examined the renal tubular uptake and the internalization rote of lysozyme after its intravenous injection in the wintering frog Rana temporaria using immunohisto- and immunocytochemistry and specific markers for some endocytic compartments. The distinct expression of megalin and cubilin in the proximal tubule cells of lysozyme-injected frogs was revealed whereas kidney tissue of control animals showed no positive immunoreactivity. Lysozyme was detected in the apical endocytic compartment of the tubular cells and colocalized with clathrin 10 min after injection. After 20 min, lysozyme was located in the subapical compartment negative to clathrin (endosomes, and intracellular trafficking of lysozyme was coincided with the distribution of megalin and cubilin. However, internalized protein was retained in the endosomes and did not reach lysosomes within 30 min after treatment that may indicate the inhibition of intracellular trafficking in hibernating frogs. For the first time, we provided the evidence that lysozyme is filtered through the glomeruli and absorbed by receptor-mediated clathrin-dependent endocytosis in the frog proximal tubule cells. Thus, the protein uptake in the amphibian mesonephros is mediated by megalin and cubilin that confirms a critical role of endocytic receptors in the renal reabsorption of proteins in amphibians as in mammals.

Renal tubular dysfunction nephrocalcinosis in a patient with BetaThalassemia Minor

International Nuclear Information System (INIS)

Prabahar, M.R.; Jain, M.; Chandrasekaran, V.; Indumathi, E.; Soundrarajan, P.

2008-01-01

Thalassemia is a hereditary anemia resulting from defect in hemoglobinproduction. Beta thalassemia is due to impaired production. Beta thalassemiais due to impaired production of beta globin chains, leading to a relativeexcess of alpha globin chains. The term beta thalassemia minor is used todescribe heterozygotes, who carry one normal beta globin and one betathalassemic allele. The vast majority of these patients are asymptomatic.However, a variety of renal tubular abnormalities including hypercaliuria,hypomagnesemia with renal magnesium wasting, decreased tubular absorption ofphosphorous, hypouricemia with renal uric acid wasting, renal glycosuria andtubular proteinuria have been described even in patients with betathalassemia minor. We here in report a 24-year old patient who was found tohave thalassemia minor and nephrocalcinosis with evidence of renal tubulardysfunction. Investigations revealed normal renal function, hypercalciuria,reduced tubular reabsorption of phosphorous, hypomagnesemia and renalmagnesium wasting. Screening for aminoaciduria was found to be negative. Anacid loading test revealed normal urinary acidification. Ultrasonogram of theabdomen revealed nephrocalcinosis and splenomegaly. Detailed work up foranemia showed normal white cell and platelet count while peripheral smearshowed microcytic hypochromic anemia with few target cells. Hemoglobinelectrophoresis revealed hemoglobin A of 92%, hemoglobin A2 of 6.2% andhemoglobin F of 1.8% consistent with beta thalassemia minor. Her parentalscreening was normal. A diagnosis of beta thalassemia minor with renaltubular dysfunction was made and the patient was started on thiazidediuretics to reduce hypercalciuria and advised regular follow-up. (author)

Adenosine contribution to normal renal physiology and chronic kidney disease.

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Oyarzún, Carlos; Garrido, Wallys; Alarcón, Sebastián; Yáñez, Alejandro; Sobrevia, Luis; Quezada, Claudia; San Martín, Rody

2017-06-01

Adenosine is a nucleoside that is particularly interesting to many scientific and clinical communities as it has important physiological and pathophysiological roles in the kidney. The distribution of adenosine receptors has only recently been elucidated; therefore it is likely that more biological roles of this nucleoside will be unveiled in the near future. Since the discovery of the involvement of adenosine in renal vasoconstriction and regulation of local renin production, further evidence has shown that adenosine signaling is also involved in the tubuloglomerular feedback mechanism, sodium reabsorption and the adaptive response to acute insults, such as ischemia. However, the most interesting finding was the increased adenosine levels in chronic kidney diseases such as diabetic nephropathy and also in non-diabetic animal models of renal fibrosis. When adenosine is chronically increased its signaling via the adenosine receptors may change, switching to a state that induces renal damage and produces phenotypic changes in resident cells. This review discusses the physiological and pathophysiological roles of adenosine and pays special attention to the mechanisms associated with switching homeostatic nucleoside levels to increased adenosine production in kidneys affected by CKD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Acute renal response to rapid onset respiratory acidosis.

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Ramadoss, Jayanth; Stewart, Randolph H; Cudd, Timothy A

2011-03-01

Renal strong ion compensation to chronic respiratory acidosis has been established, but the nature of the response to acute respiratory acidosis is not well defined. We hypothesized that the response to acute respiratory acidosis in sheep is a rapid increase in the difference in renal fractional excretions of chloride and sodium (Fe(Cl) - Fe(Na)). Inspired CO(2) concentrations were increased for 1 h to significantly alter P(a)CO(2) and pH(a) from 32 ± 1 mm Hg and 7.52 ± 0.02 to 74 ± 2 mm Hg and 7.22 ± 0.02, respectively. Fe(Cl) - Fe(Na) increased significantly from 0.372 ± 0.206 to 1.240 ± 0.217% and returned to baseline at 2 h when P(a)CO(2) and pH(a) were 37 ± 0.6 mm Hg and 7.49 ± 0.01, respectively. Arterial pH and Fe(Cl) - Fe(Na) were significantly correlated. We conclude that the kidney responds rapidly to acute respiratory acidosis, within 30 min of onset, by differential reabsorption of sodium and chloride.

Reduced reabsorption and enhanced propagation induced by large Stokes shift in quantum dot-filled optical fiber

Energy Technology Data Exchange (ETDEWEB)

Wu, Hua; Zhang, Yu, E-mail: yuzhang@jlu.edu.cn; Lu, Min; Liu, Wenyan [Jilin University, State Key Laboratory on Integrated Optoelectronics and College of Electronic Science and Engineering (China); Xu, Jian [The Pennsylvania State University, Department of Engineering Science and Mechanics (United States); Yu, William W., E-mail: wyu6000@gmail.com [Jilin University, State Key Laboratory on Integrated Optoelectronics and College of Electronic Science and Engineering (China)

2016-07-15

With tunable emission wavelength, high photoluminescence quantum yield, and broad absorption, colloidal quantum dots are attractive for the application in optical fiber as dopants. However, most of the quantum dots have a large overlap between their absorption and photoluminescence spectra, resulting in reabsorption loss which hinders the realization of long-distance waveguides. Therefore, ZnCuInS/ZnSe/ZnS quantum dots with large Stokes shift were proposed to fabricate a liquid-core optical fiber in this work. In this work, ZnCuInS/ZnSe/ZnS QDs with an average size of 3.3 nm were synthesized and the optical properties of the QD-filled fiber were also investigated as a function of fiber length and doping concentration. Compared to the control sample filled with CdSe/CdS/ZnS quantum dots, the ZnCuInS/ZnSe/ZnS quantum dot-based waveguides showed reduced reabsorption and enhanced signal propagation, which demonstrates great potential of large Stokes-shift quantum dots in optical waveguide devices.Graphical AbstractA reduced reabsorption and enhanced propagation of ZnCuInS/ZnSe/ZnS QDs-doped liquid-core optical fiber was achieved due to the large Stokes shift.

Lithium clearance and renal tubular sodium handling during acute and long-term nifedipine treatment in essential hypertension

DEFF Research Database (Denmark)

Bruun, N E; Ibsen, H; Skøtt, P

1988-01-01

1. In two separate studies the lithium clearance method was used to evaluate the influence of acute and long-term nifedipine treatment on renal tubular sodium reabsorption. 2. In the acute study, after a 4 week placebo period two doses of 20 mg of nifedipine decreased supine blood pressure from 155...... were also unchanged, as were potassium clearance, urine flow and body weight. 3. In the long-term study, lithium clearance, glomerular filtration rate, sodium clearance, potassium clearance, urine flow and body fluid volumes were measured after a 4 weeks placebo period and after 6 and 12 weeks....../101 (20.6/13.5) +/- 11/4 (1.5/0.5) to 139/88 (18.5/11.7) +/- 16/9 (2.1/1.2) mmHg (kPa) (means +/- SD; P less than 0.01). Lithium clearance, glomerular filtration rate and sodium clearance did not change. Therefore the calculated values of absolute proximal and absolute distal sodium reabsorption rates...

Human Sodium Phosphate Transporter 4 (hNPT4/SLC17A3) as a Common Renal Secretory Pathway for Drugs and Urate*

Science.gov (United States)

Jutabha, Promsuk; Anzai, Naohiko; Kitamura, Kenichiro; Taniguchi, Atsuo; Kaneko, Shuji; Yan, Kunimasa; Yamada, Hideomi; Shimada, Hidetaka; Kimura, Toru; Katada, Tomohisa; Fukutomi, Toshiyuki; Tomita, Kimio; Urano, Wako; Yamanaka, Hisashi; Seki, George; Fujita, Toshiro; Moriyama, Yoshinori; Yamada, Akira; Uchida, Shunya; Wempe, Michael F.; Endou, Hitoshi; Sakurai, Hiroyuki

2010-01-01

The evolutionary loss of hepatic urate oxidase (uricase) has resulted in humans with elevated serum uric acid (urate). Uricase loss may have been beneficial to early primate survival. However, an elevated serum urate has predisposed man to hyperuricemia, a metabolic disturbance leading to gout, hypertension, and various cardiovascular diseases. Human serum urate levels are largely determined by urate reabsorption and secretion in the kidney. Renal urate reabsorption is controlled via two proximal tubular urate transporters: apical URAT1 (SLC22A12) and basolateral URATv1/GLUT9 (SLC2A9). In contrast, the molecular mechanism(s) for renal urate secretion remain unknown. In this report, we demonstrate that an orphan transporter hNPT4 (human sodium phosphate transporter 4; SLC17A3) was a multispecific organic anion efflux transporter expressed in the kidneys and liver. hNPT4 was localized at the apical side of renal tubules and functioned as a voltage-driven urate transporter. Furthermore, loop diuretics, such as furosemide and bumetanide, substantially interacted with hNPT4. Thus, this protein is likely to act as a common secretion route for both drugs and may play an important role in diuretics-induced hyperuricemia. The in vivo role of hNPT4 was suggested by two hyperuricemia patients with missense mutations in SLC17A3. These mutated versions of hNPT4 exhibited reduced urate efflux when they were expressed in Xenopus oocytes. Our findings will complete a model of urate secretion in the renal tubular cell, where intracellular urate taken up via OAT1 and/or OAT3 from the blood exits from the cell into the lumen via hNPT4. PMID:20810651

Prevalence of renal dysfunction and its influence on functional capacity in elderly patients with stable chronic heart failure

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Stanojević Dragana

2012-01-01

Full Text Available Bacground/Aim. Chronic heart failure (CHF is highly prevalent and constitutes an important public health problem around the world. In spite of a large number of pharmacological agents that successfully decrease mortality in CHF, the effects on exercise tolerance and quality of life are modest. Renal dysfunction is extremely common in patients with CHF and it is strongly related not only to increased mortality and morbidity but to a significant decrease in exercise tolerance, as well. The aim of our study was to investigate the prevalence and influence of the renal dysfunction on functional capacity in the elderly CHF patients. Methods. We included 127 patients aged over 65 years in a stable phase of CHF. The diagnosis of heart failure was based on the latest diagnostic principles of the European Society of Cardiology. The estimated glomerular filtration rate (eGRF was determined by the abbreviated Modification of Diet in Renal Disease (MDRD2 formula, and patients were categorized using the Kidney Disease Outcomes Quality Initiative (K/DOQI classification system. Functional capacity was determined by the 6 minute walking test (6MWT. Results. Among 127 patients, 90 were men. The average age was 72.5 ± 4.99 years and left ventricular ejection fraction (LVEF was 40.22 ± 9.89%. The average duration of CHF was 3.79 ± 4.84 years. Ninty three (73.2% patients were in New York Heart Association (NYHA class II and 34 (26.8% in NYHA class III. Normal renal function (eGFR ≥ 90 mL/min had 8.9% of participants, 57.8% had eGFR between 60-89 mL/min (stage 2 or mild reduction in GFR according to K/DOQI classification, 32.2% had eGFR between 30-59 mL/min (stage 3 or moderate reduction in GFR and 1.1% had eGFR between 15-29 mL/min (stage 4 or severe reduction in GFR. We found statistically significant correlation between eGFR and 6 minute walking distance (6MWD (r = 0.390, p < 0.001, LVEF (r = 0.268, p < 0.05, NYHA class (ς = -0.269, p < 0.05 and age (r = - 0

Renal Proteome in Mice with Different Susceptibilities to Fluorosis

Science.gov (United States)

Peres-Buzalaf, Camila; Salvato, Fernanda; Labate, Carlos Alberto; Everett, Eric T.; Whitford, Gary Milton; Buzalaf, Marília Afonso Rabelo

2013-01-01

A/J and 129P3/J mouse strains have different susceptibilities to dental fluorosis due to their genetic backgrounds. They also differ with respect to several features of fluoride (F) metabolism and metabolic handling of water. This study was done to determine whether differences in F metabolism could be explained by diversities in the profile of protein expression in kidneys. Weanling, male A/J mice (susceptible to dental fluorosis, n = 18) and 129P3/J mice (resistant, n = 18) were housed in pairs and assigned to three groups given low-F food and drinking water containing 0, 10 or 50 ppm [F] for 7 weeks. Renal proteome profiles were examined using 2D-PAGE and LC-MS/MS. Quantitative intensity analysis detected between A/J and 129P3/J strains 122, 126 and 134 spots differentially expressed in the groups receiving 0, 10 and 50 ppmF, respectively. From these, 25, 30 and 32, respectively, were successfully identified. Most of the proteins were related to metabolic and cellular processes, followed by response to stimuli, development and regulation of cellular processes. In F-treated groups, PDZK-1, a protein involved in the regulation of renal tubular reabsorption capacity was down-modulated in the kidney of 129P3/J mice. A/J and 129P3/J mice exhibited 11 and 3 exclusive proteins, respectively, regardless of F exposure. In conclusion, proteomic analysis was able to identify proteins potentially involved in metabolic handling of F and water that are differentially expressed or even not expressed in the strains evaluated. This can contribute to understanding the molecular mechanisms underlying genetic susceptibility to dental fluorosis, by indicating key-proteins that should be better addressed in future studies. PMID:23308176

Renal glucose handling in diabetes and sodium glucose cotransporter 2 inhibition

Directory of Open Access Journals (Sweden)

Resham Raj Poudel

2013-01-01

Full Text Available The kidneys play a major role in glucose homeostasis through its utilization, gluconeogenesis, and reabsorption via sodium glucose cotransporters (SGLTs. The defective renal glucose handling from upregulation of SGLTs, mainly the SGLT2, plays a fundamental role in the pathogenesis of type 2 diabetes mellitus. Genetic mutations in a SGLT2 isoform that results in benign renal glycosuria, as well as clinical studies with SGLT2 inhibitors in type 2 diabetes support the potential of this approach. These studies indicate that inducing glycosuria by suppressing SGLT2 can reduce plasma glucose and A1c levels, as well as decrease weight, resulting in improved β-cell function and enhanced insulin sensitivity in liver and muscle. Because the mechanism of SGLT2 inhibition is independent of insulin secretion and sensitivity, these agents can be combined with other antidiabetic agents, including exogenous insulin. This class represents a novel therapeutic approach with potential for the treatment of both type 2 and type 1 diabetes.

Renal handling of sodium and water in the hypothyroid rat

Science.gov (United States)

Michael, Ulrich F.; Barenberg, Robert L.; Chavez, Rafaelita; Vaamonde, Carlos A.; Papper, Solomon

1972-01-01

Hypothyroid rats were examined with conventional renal clearance and micropuncture techniques to elicit the mechanism and site within the nephron responsible for the increased salt and water excretion observed in these animals. When compared with age-matched control rats, a decrease in inulin clearance of 30% (P < 0.001) and in Hippuran clearance of 32% (P < 0.005) was observed in the hypothyroid rats. Absolute excretion of sodium and water was increased 3-fold (P < 0.02) and 2-fold (P < 0.025), respectively, while fractional excretion of sodium and water was increased 4.3-fold (P < 0.02) and 2.9-fold (P < 0.05), respectively, in the hypothyroid animals. Fractional proximal reabsorption of sodium as assessed from proximal tubular fluid to plasma ratios of inulin ([TF/P]IN) was found to be decreased by 28% (P < 0.001) in the hypothyroid rats. Superficial single nephron filtration rate was reduced proportionately to the decrease in total filtration rate in the hypothyroid rats. These data indicate that the proximal tubule is one of the sites of diminished sodium and water reabsorption in the hypothyroid rat. The data also suggest that the observed decrease in glomerular filtration rate in the hypothyroid animals is not caused by a decrease in the number of functioning nephrons and that the observed increase in sodium and water excretion is not caused by a redistribution of filtrate from juxtamedullary to superficial nephrons. Although the exact mechanisms of the observed changes in proximal tubular function remain unknown, the data suggest that they are probably related to the lack of thyroid hormone. Whatever their mechanism, it appears that the enhanced sodium and water excretion observed in the hypothyroid animals must be determined by further reduction in tubular sodium reabsorption in the distal nephron. PMID:5024038

Renal acidification defects in medullary sponge kidney

DEFF Research Database (Denmark)

Osther, P J; Hansen, A B; Røhl, H F

1988-01-01

Thirteen patients with medullary sponge kidney underwent a short ammonium chloride loading test to investigate their renal acidification capacity. All but 1 presented with a history of recurrent renal calculi and showed bilateral widespread renal medullary calcification on X-ray examination. Nine...... of renal calculi in medullary sponge kidney, have considerable therapeutic implications....

Mechanistic insights of intestinal absorption and renal conservation of folate in chronic alcoholism.

Science.gov (United States)

Wani, Nissar Ahmad; Thakur, Shilpa; Najar, Rauf Ahmad; Nada, Ritambhara; Khanduja, Krishan Lal; Kaur, Jyotdeep

2013-03-01

Folate mediated one-carbon metabolism is of fundamental importance for various cellular processes, including DNA synthesis and methylation of biological molecules. Due to the exogenous requirement of folate in mammals, there exists a well developed epithelial folate transport system for regulation of normal folate homeostasis. The intestinal and renal folate uptake is tightly and diversely regulated and disturbances in folate homeostasis like in alcoholism have pathological consequences. The study was sought to delineate the regulatory mechanism of folate uptake in intestine and reabsorption in renal tubular cells that could evaluate insights of malabsorption during alcoholism. The folate transporters PCFT and RFC were found to be associated with lipid rafts of membrane surfaces in intestine and kidney. Importantly, the observed lower intestinal and renal folate uptake was associated with decreased levels of folate transporter viz. PCFT and RFC in lipid rafts of intestinal and renal membrane surfaces. The decreased association of folate transporters in lipid rafts was associated with decreased protein and mRNA levels. In addition, immunohistochemical studies showed that alcoholic conditions deranged that localization of PCFT and RFC. These findings could explain the possible mechanistic insights that may result in folate malabsorption during alcoholism. Copyright © 2013 Elsevier Inc. All rights reserved.

Insulin's acute effects on glomerular filtration rate correlate with insulin sensitivity whereas insulin's acute effects on proximal tubular sodium reabsorption correlate with salt sensitivity in normal subjects

NARCIS (Netherlands)

ter Maaten, JC; Bakker, SJL; Serne, EH; ter Wee, PM; Gans, ROB

1999-01-01

Background. Insulin induces increasing distal tubular sodium reabsorption. Opposite effects of insulin to offset insulin-induced sodium retention are supposedly increases in glomerular filtration rate (GFR) and decreases in proximal tubular sodium reabsorption. Defects in these opposing effects

Ectopic germinal center and megalin defect in primary Sjogren syndrome with renal Fanconi syndrome.

Science.gov (United States)

Wang, Jing; Wen, Yubing; Zhou, Mengyu; Shi, Xiaoxiao; Jiang, Lanping; Li, Mingxi; Yu, Yang; Li, Xuemei; Li, Xuewang; Zhang, Wen; Lundquist, Andrew L; Chen, Limeng

2017-06-02

This study reports the clinical and pathological features of 12 cases of primary Sjogren syndrome (pSS) with renal involvement presenting with proximal tubular dysfunction in a single center, and investigates the possible correlation of ectopic germinal center formation and megalin/cubilin down-expression. Clinical and pathological records were reviewed. Immunohistochemistry was carried out to detect megalin, cubilin, CD21 and IL-17 expression. Patients presented with different degrees of proximal renal tubule lesion and decreased estimated glomerular filtration rate (eGFR). Renal biopsy revealed tubulointerstitial nephritis, with tubular epithelial cell degeneration, tubular atrophy, interstitial inflammation and focal fibrosis. Immunohistochemistry revealed decreased expression of megalin and cubilin, two important multiligand protein receptors on the brush border of proximal tubular epithelial cells. IL-17 secreted by Th17 subtype effector T cells was diffusely detected in the renal proximal tubule, with a negative correlation of IL-17 and megalin expression. In addition, ectopic germinal centers characterized by CD21 + follicular dendritic cells were present in the renal interstitium. In patients with a decreased eGFR, treatment with 4 weeks of glucocorticoid therapy resulted in an improved eGFR in 75% of patients. We report 12 cases of pSS characterized by Fanconi syndrome. The decreased megalin and cubilin expression may contribute to the proximal tubular reabsorption defect, possibly secondary to Th17 infiltration and formation of ectopic germinal centers.

The Association of Albuminuria With Tubular Reabsorption of Uric Acid : Results From a General Population Cohort

NARCIS (Netherlands)

Scheven, Lieneke; Joosten, Michel M.; de Jong, Paul E.; Bakker, Stephan J. L.; Gansevoort, Ron T.

Background-Elevated albuminuria as well as an increased serum uric acid concentration is associated with poor cardiovascular outcome. We questioned whether these 2 variables (albuminuria and serum uric concentration) may be interrelated via tubular uric acid reabsorption. Methods and

The crosstalk between the kidney and the central nervous system: the role of renal nerves in blood pressure regulation.

Science.gov (United States)

Nishi, Erika E; Bergamaschi, Cássia T; Campos, Ruy R

2015-04-20

What is the topic of this review? This review describes the role of renal nerves as the key carrier of signals from the kidneys to the CNS and vice versa; the brain and kidneys communicate through this carrier to maintain homeostasis in the body. What advances does it highlight? Whether renal or autonomic dysfunction is the predominant contributor to systemic hypertension is still debated. In this review, we focus on the role of the renal nerves in a model of renovascular hypertension. The sympathetic nervous system influences the renal regulation of arterial pressure and body fluid composition. Anatomical and physiological evidence has shown that sympathetic nerves mediate changes in urinary sodium and water excretion by regulating the renal tubular water and sodium reabsorption throughout the nephron, changes in the renal blood flow and the glomerular filtration rate by regulating the constriction of renal vasculature, and changes in the activity of the renin-angiotensin system by regulating the renin release from juxtaglomerular cells. Additionally, renal sensory afferent fibres project to the autonomic central nuclei that regulate blood pressure. Hence, renal nerves play a key role in the crosstalk between the kidneys and the CNS to maintain homeostasis in the body. Therefore, the increased sympathetic nerve activity to the kidney and the renal afferent nerve activity to the CNS may contribute to the outcome of diseases, such as hypertension. © 2014 The Authors. Experimental Physiology © 2014 The Physiological Society.

Renal handling of technetium-99m DMSA in rats with proximal tubular dysfunction

International Nuclear Information System (INIS)

Provoost, A.P.; Van Aken, M.

1985-01-01

The renal handling of technetium-/sup 99m/ dimercaptosuccinic acid ([/sup 99m/Tc]DMSA) was studied in rats before and after treatment with Na-maleate (2 mmol/kg i.v.). In the control period, when measured 2 hr after the intravenous injection of [/sup 99m/Tc]DMSA, 39.9% of the injected dose was in the kidneys and 14.6% was in the bladder. After Na-maleate treatment, only 6.4% of the injected dose of [/sup 99m/Tc]DMSA was retained in the kidneys while 37.9% was found in the bladder. Subsequent studies revealed that Na-maleate produced a fall in the glomerular filtration rate, the effective renal plasma flow, and a generalized proximal tubular dysfunction. The latter was characterized by polyuria and an increased excretion of glucose, protein, albumin, calcium, and inorganic phosphate. It was concluded that proximal tubular dysfunction markedly alters the renal handling of [/sup 99m/Tc]DMSA. Whether this augmented urinary excretion is due to an inhibition of reabsorption or an enhanced cellular efflux of [/sup 99m/Tc]DMSA remains to be answered

Role of NH3 and NH4+ transporters in renal acid-base transport.

Science.gov (United States)

Weiner, I David; Verlander, Jill W

2011-01-01

Renal ammonia excretion is the predominant component of renal net acid excretion. The majority of ammonia excretion is produced in the kidney and then undergoes regulated transport in a number of renal epithelial segments. Recent findings have substantially altered our understanding of renal ammonia transport. In particular, the classic model of passive, diffusive NH3 movement coupled with NH4+ "trapping" is being replaced by a model in which specific proteins mediate regulated transport of NH3 and NH4+ across plasma membranes. In the proximal tubule, the apical Na+/H+ exchanger, NHE-3, is a major mechanism of preferential NH4+ secretion. In the thick ascending limb of Henle's loop, the apical Na+-K+-2Cl- cotransporter, NKCC2, is a major contributor to ammonia reabsorption and the basolateral Na+/H+ exchanger, NHE-4, appears to be important for basolateral NH4+ exit. The collecting duct is a major site for renal ammonia secretion, involving parallel H+ secretion and NH3 secretion. The Rhesus glycoproteins, Rh B Glycoprotein (Rhbg) and Rh C Glycoprotein (Rhcg), are recently recognized ammonia transporters in the distal tubule and collecting duct. Rhcg is present in both the apical and basolateral plasma membrane, is expressed in parallel with renal ammonia excretion, and mediates a critical role in renal ammonia excretion and collecting duct ammonia transport. Rhbg is expressed specifically in the basolateral plasma membrane, and its role in renal acid-base homeostasis is controversial. In the inner medullary collecting duct (IMCD), basolateral Na+-K+-ATPase enables active basolateral NH4+ uptake. In addition to these proteins, several other proteins also contribute to renal NH3/NH4+ transport. The role and mechanisms of these proteins are discussed in depth in this review.

Roles of estrogen and progesterone in modulating renal nerve function in the rat kidney

International Nuclear Information System (INIS)

Graceli, J.B.; Cicilini, M.A.; Bissoli, N.S.; Abreu, G.R.; Moysés, M.R.

2013-01-01

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 (FE Na + and FE Cl - , respectively) and renal and plasma catecholamine release concentrations. FE Na + , FE Cl - , 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 FE Na + , FE Cl - , 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

Inherited renal tubulopathies associated with metabolic alkalosis: effects on blood pressure.

Science.gov (United States)

Ariceta, Gema; Rodríguez-Soriano, Juan

2006-11-01

Inherited tubular disorders associated with metabolic alkalosis are caused by several gene mutations encoding different tubular transporters responsible for NaCl renal handling. Body volume and renin-angiotensin-aldosterone system status are determined by NaCl reabsorption in the distal nephron. Two common hallmarks in affected individuals: hypokalemia and normal / high blood pressure, support the differential diagnosis. Bartter's syndrome, characterized by hypokalemia and normal blood pressure, is a heterogenic disease caused by the loss of function of SLC12A1 (type 1), KCNJ1 (type 2), CLCNKB (type 3), or BSND genes (type 4). As a result, patients present with renal salt wasting and hypercalciuria. Gitelman's syndrome is caused by the loss of funcion of the SLC12A3 gene and may resemble Bartter's syndrome, though is associated with the very low urinary calcium. Liddle's syndrome, also with similar phenotype but with hypertension, is produced by the gain of function of the SNCC1B or SNCC1G genes, and must be distinguished from other entities of inherited hypertension such as Apparently Mineralocorticoid Excess, of glucocorticoid remediable hypertension.

Cellular transport of l-arginine determines renal medullary blood flow in control rats, but not in diabetic rats despite enhanced cellular uptake capacity.

Science.gov (United States)

Persson, Patrik; Fasching, Angelica; Teerlink, Tom; Hansell, Peter; Palm, Fredrik

2017-02-01

Diabetes mellitus is associated with decreased nitric oxide bioavailability thereby affecting renal blood flow regulation. Previous reports have demonstrated that cellular uptake of l-arginine is rate limiting for nitric oxide production and that plasma l-arginine concentration is decreased in diabetes. We therefore investigated whether regional renal blood flow regulation is affected by cellular l-arginine uptake in streptozotocin-induced diabetic rats. Rats were anesthetized with thiobutabarbital, and the left kidney was exposed. Total, cortical, and medullary renal blood flow was investigated before and after renal artery infusion of increasing doses of either l-homoarginine to inhibit cellular uptake of l-arginine or N ω -nitro- l-arginine methyl ester (l-NAME) to inhibit nitric oxide synthase. l-Homoarginine infusion did not affect total or cortical blood flow in any of the groups, but caused a dose-dependent reduction in medullary blood flow. l-NAME decreased total, cortical and medullary blood flow in both groups. However, the reductions in medullary blood flow in response to both l-homoarginine and l-NAME were more pronounced in the control groups compared with the diabetic groups. Isolated cortical tubular cells displayed similar l-arginine uptake capacity whereas medullary tubular cells isolated from diabetic rats had increased l-arginine uptake capacity. Diabetics had reduced l-arginine concentrations in plasma and medullary tissue but increased l-arginine concentration in cortical tissue. In conclusion, the reduced l-arginine availability in plasma and medullary tissue in diabetes results in reduced nitric oxide-mediated regulation of renal medullary hemodynamics. Cortical blood flow regulation displays less dependency on extracellular l-arginine and the upregulated cortical tissue l-arginine may protect cortical hemodynamics in diabetes. Copyright © 2017 the American Physiological Society.

Validation of phenol red versus gravimetric method for water reabsorption correction and study of gender differences in Doluisio's absorption technique.

Science.gov (United States)

Tuğcu-Demiröz, Fatmanur; Gonzalez-Alvarez, Isabel; Gonzalez-Alvarez, Marta; Bermejo, Marival

2014-10-01

The aim of the present study was to develop a method for water flux reabsorption measurement in Doluisio's Perfusion Technique based on the use of phenol red as a non-absorbable marker and to validate it by comparison with gravimetric procedure. The compounds selected for the study were metoprolol, atenolol, cimetidine and cefadroxil in order to include low, intermediate and high permeability drugs absorbed by passive diffusion and by carrier mediated mechanism. The intestinal permeabilities (Peff) of the drugs were obtained in male and female Wistar rats and calculated using both methods of water flux correction. The absorption rate coefficients of all the assayed compounds did not show statistically significant differences between male and female rats consequently all the individual values were combined to compare between reabsorption methods. The absorption rate coefficients and permeability values did not show statistically significant differences between the two strategies of concentration correction. The apparent zero order water absorption coefficients were also similar in both correction procedures. In conclusion gravimetric and phenol red method for water reabsorption correction are accurate and interchangeable for permeability estimation in closed loop perfusion method. Copyright © 2014 Elsevier B.V. All rights reserved.

Technique of experimental measurements of the optical thickness of a pulse discharge plasma channel in water on a contour reabsorption lines of hydrogen Hα

Directory of Open Access Journals (Sweden)

O. A. Fedorovich

2010-03-01

Full Text Available In this work the results of development and application of the technique of experimental definition of optical thickness (τ of the pulse discharge plasma channel in water which are based on the distribution of radiation intensities on contour reabsorption lines of hydrogen Ha (656.3 nm are given. Optical thickness of continues spectrum was defined by extrapolation of intensities in far wing of contour reabsorption lines of hydrogen Ha, where t value did not vary any more, and the line smoothly transferred in continuous spectrum. The atomic concentration Na, received on a method of definition of t on a contour reabsorption lines of hydrogen Ha., agreed with calculation obtained from the equation of the plasma state. The recommendations on the correct definition of optical thickness of plasma of pulse discharge in liquids are given.

Effect of metabolic acidosis on renal tubular sodium handling in rats as determined by lithium clearance

Directory of Open Access Journals (Sweden)

Menegon L.F.

1998-01-01

Full Text Available Systemic metabolic acidosis is known to cause a decrease in salt and water reabsorption by the kidney. We have used renal lithium clearance to investigate the effect of chronic, NH4Cl-induced metabolic acidosis on the renal handling of Na+ in male Wistar-Hannover rats (200-250 g. Chronic acidosis (pH 7.16 ± 0.13 caused a sustained increase in renal fractional Na+ excretion (267.9 ± 36.4%, accompanied by an increase in fractional proximal (113.3 ± 3.6% and post-proximal (179.7 ± 20.2% Na+ and urinary K+ (163.4 ± 5.6% excretion when compared to control and pair-fed rats. These differences occurred in spite of an unchanged creatinine clearance and Na+ filtered load. A lower final body weight was observed in the acidotic (232 ± 4.6 g and pair-fed (225 ± 3.6 g rats compared to the controls (258 ± 3.7 g. In contrast, there was a significant increase in the kidney weights of acidotic rats (1.73 ± 0.05 g compared to the other experimental groups (control, 1.46 ± 0.05 g; pair-fed, 1.4 ± 0.05 g. We suggest that altered renal Na+ and K+ handling in acidotic rats may result from a reciprocal relationship between the level of metabolism in renal tubules and ion transport.

Mechanisms controlling renal hemodynamics and electrolyte excretion during amino acids

International Nuclear Information System (INIS)

Woods, L.L.; Mizelle, H.L.; Montani, J.P.; Hall, J.E.

1986-01-01

Our purpose was to investigate the mechanisms by which increased plasma amino acids elevate renal blood flow (RBF) and glomerular filtration rate (GFR). Since transport of amino acids and Na + is linked in the proximal tubule, the authors hypothesized that increased amino acids might stimulate proximal tubular Na + reabsorption (PR/sub Na/) and thus increase RBF and GFR by a macula densa feedback mechanism. A solution of four amino acids (Ala, Ser, Gly, Pro) was infused intravenously into anesthetized dogs with normal kidneys (NK) and with kidneys in which the tubuloglomerular feedback mechanism was blunted by lowering renal artery pressure (LPK) or blocked by making the kidneys nonfiltering (NFK). In NK, RBF and GFR increased by 35 +/- 4% and 30 +/- 7% after 90 min of amino acid infusion, while PR/sub Na/ (estimated from lithium clearance) and O 2 consumption increased by 31 +/- 5% and 29 +/- 5% and distal Na + delivery remained relatively constant. Autoregulation of RBF and GFR in response to step deceases in renal artery pressure was impaired during amino acids in NK. The hemodynamic responses to amino acids were abolished in LPK and NFK. Infusion of the nonmetabolized α-aminoisobutyric acid into NK produced changes in renal hemodynamics that were similar to the responses observed with the four metabolizable amino acids. These data are consistent with the hypothesis that elevation of plasma amino acids increases RBF and GFR by a mechanism that requires an intact macula densa feedback. Metabolism of the amino acids does not appear to be necessary for these changes to occur

Mechanisms controlling renal hemodynamics and electrolyte excretion during amino acids

Energy Technology Data Exchange (ETDEWEB)

Woods, L.L.; Mizelle, H.L.; Montani, J.P.; Hall, J.E.

1986-08-01

Our purpose was to investigate the mechanisms by which increased plasma amino acids elevate renal blood flow (RBF) and glomerular filtration rate (GFR). Since transport of amino acids and Na is linked in the proximal tubule, the authors hypothesized that increased amino acids might stimulate proximal tubular Na reabsorption (PR/sub Na/) and thus increase RBF and GFR by a macula densa feedback mechanism. A solution of four amino acids (Ala, Ser, Gly, Pro) was infused intravenously into anesthetized dogs with normal kidneys (NK) and with kidneys in which the tubuloglomerular feedback mechanism was blunted by lowering renal artery pressure (LPK) or blocked by making the kidneys nonfiltering (NFK). In NK, RBF and GFR increased by 35 +/- 4% and 30 +/- 7% after 90 min of amino acid infusion, while PR/sub Na/ (estimated from lithium clearance) and O2 consumption increased by 31 +/- 5% and 29 +/- 5% and distal Na delivery remained relatively constant. Autoregulation of RBF and GFR in response to step deceases in renal artery pressure was impaired during amino acids in NK. The hemodynamic responses to amino acids were abolished in LPK and NFK. Infusion of the nonmetabolized -aminoisobutyric acid into NK produced changes in renal hemodynamics that were similar to the responses observed with the four metabolizable amino acids. These data are consistent with the hypothesis that elevation of plasma amino acids increases RBF and GFR by a mechanism that requires an intact macula densa feedback. Metabolism of the amino acids does not appear to be necessary for these changes to occur.

Effect of angiotensin II receptor blockade on proximal tubular fluid reabsorption

DEFF Research Database (Denmark)

Leyssac, P P; Karlsen, F M; Holstein-Rathlou, N H

1997-01-01

flow rate decreased by 2.0 +/- 0.8 nl/min, and early distal NaCl concentration decreased by 4.3 +/- 0.8 mM (mean +/- SE). No changes were observed after microperfusion with saline. Because the tubuloglomerular feedback mechanism was operating in the closed-loop mode, the decreased NaCl load...... to the macula densa will be compensated by an increase in the single-nephron glomerular filtration rate. In agreement with this, the early proximal flow rate, measured proximal to the site of losartan administration, increased by 5.7 +/- 1.3 nl/min. The increase in the rate of proximal reabsorption between...

Peritoneal transport in CAPD patients with permanent loss of ultrafiltration capacity

International Nuclear Information System (INIS)

Heimbuerger, O.W.; Waniewski, J.; Werynski, A.; Tranaeus, A.; Lindholm, B.

1990-01-01

During a 10 year period, 14 out of 227 patients (6.2%) undergoing continuous ambulatory peritoneal dialysis (CAPD) developed permanent loss of ultrafiltration capacity (UFC). The risk of UFC loss increased from 2.6% after one year to 30.9% after six years of treatment. A six hour, single dwell study with glucose 3.86% dialysis fluid was carried out in nine of the UFC loss patients and in 18 CAPD patients with normal UFC. Intraperitoneal dialysate volumes were calculated using 131I-tagged albumin (RISA) as volume marker with a correction applied for its elimination from the peritoneal cavity. The RISA elimination coefficient (KE), which can serve as an estimation of the upper limit of the lymphatic flow, was also calculated. Diffusive mass transport coefficients (KBD) for investigated solutes (glucose, creatinine, urea, potassium, total protein, albumin and beta 2-microglobulin) were calculated during a period of dialysate isovolemia. Two patterns of UFC loss were observed: (a) seven patients had high KBD values for small solutes resulting in rapid uptake of glucose, whereas KBD values for proteins were normal; (b) two patients had normal KBD values but a threefold increase both in the fluid reabsorption rate and KE. We conclude that loss of the osmotic driving force (due to increased diffusive mass transport for small solutes) and increased fluid reabsorption (possibly due to increased lymphatic reabsorption) are the two major causes of permanent loss of UFC in CAPD patients

A novel description of FDG excretion in the renal system: application to metformin-treated models

Science.gov (United States)

Garbarino, S.; Caviglia, G.; Sambuceti, G.; Benvenuto, F.; Piana, M.

2014-05-01

This paper introduces a novel compartmental model describing the excretion of 18F-fluoro-deoxyglucose (FDG) in the renal system and a numerical method based on the maximum likelihood for its reduction. This approach accounts for variations in FDG concentration due to water re-absorption in renal tubules and the increase of the bladder’s volume during the FDG excretion process. From the computational viewpoint, the reconstruction of the tracer kinetic parameters is obtained by solving the maximum likelihood problem iteratively, using a non-stationary, steepest descent approach that explicitly accounts for the Poisson nature of nuclear medicine data. The reliability of the method is validated against two sets of synthetic data realized according to realistic conditions. Finally we applied this model to describe FDG excretion in the case of animal models treated with metformin. In particular we show that our approach allows the quantitative estimation of the reduction of FDG de-phosphorylation induced by metformin.

A novel description of FDG excretion in the renal system: application to metformin-treated models

International Nuclear Information System (INIS)

Garbarino, S; Caviglia, G; Piana, M; Sambuceti, G; Benvenuto, F

2014-01-01

This paper introduces a novel compartmental model describing the excretion of 18F-fluoro-deoxyglucose (FDG) in the renal system and a numerical method based on the maximum likelihood for its reduction. This approach accounts for variations in FDG concentration due to water re-absorption in renal tubules and the increase of the bladder’s volume during the FDG excretion process. From the computational viewpoint, the reconstruction of the tracer kinetic parameters is obtained by solving the maximum likelihood problem iteratively, using a non-stationary, steepest descent approach that explicitly accounts for the Poisson nature of nuclear medicine data. The reliability of the method is validated against two sets of synthetic data realized according to realistic conditions. Finally we applied this model to describe FDG excretion in the case of animal models treated with metformin. In particular we show that our approach allows the quantitative estimation of the reduction of FDG de-phosphorylation induced by metformin. (paper)

The renal effects of SGLT2 inhibitors and a mini-review of the literature.

Science.gov (United States)

Andrianesis, Vasileios; Glykofridi, Spyridoula; Doupis, John

2016-12-01

Sodium-glucose linked transporter 2 (SGLT2) inhibitors are a new and promising class of antidiabetic agents which target renal tubular glucose reabsorption. Their action is based on the blockage of SGLT2 sodium-glucose cotransporters that are located at the luminal membrane of tubular cells of the proximal convoluted tubule, inducing glucosuria. It has been proven that they significantly reduce glycated hemoglobin (HbA1c), along with fasting and postprandial plasma glucose in patients with type 2 diabetes mellitus (T2DM). The glucosuria-induced caloric loss as well as the osmotic diuresis significantly decrease body weight and blood pressure, respectively. Given that SGLT2 inhibitors do not interfere with insulin action and secretion, their efficacy is sustained despite the progressive β-cell failure in T2DM. They are well tolerated, with a low risk of hypoglycemia. Their most frequent adverse events are minor: genital and urinal tract infections. Recently, it was demonstrated that empagliflozin presents a significant cardioprotective effect. Although the SGLT2 inhibitors' efficacy is affected by renal function, new data have been presented that some SGLT2 inhibitors, even in mild and moderate renal impairment, induce significant HbA1c reduction. Moreover, recent data indicate that SGLT2 inhibition has a beneficial renoprotective effect. The role of this review paper is to explore the current evidence on the renal effects of SGLT2 inhibitors.

Expression profiles of genes involved in xenobiotic metabolism and disposition in human renal tissues and renal cell models

Energy Technology Data Exchange (ETDEWEB)

Van der Hauwaert, Cynthia; Savary, Grégoire [EA4483, Université de Lille 2, Faculté de Médecine de Lille, Pôle Recherche, 59045 Lille (France); Buob, David [Institut de Pathologie, Centre de Biologie Pathologie Génétique, Centre Hospitalier Régional Universitaire de Lille, 59037 Lille (France); Leroy, Xavier; Aubert, Sébastien [Institut de Pathologie, Centre de Biologie Pathologie Génétique, Centre Hospitalier Régional Universitaire de Lille, 59037 Lille (France); Institut National de la Santé et de la Recherche Médicale, UMR837, Centre de Recherche Jean-Pierre Aubert, Equipe 5, 59045 Lille (France); Flamand, Vincent [Service d' Urologie, Hôpital Huriez, Centre Hospitalier Régional Universitaire de Lille, 59037 Lille (France); Hennino, Marie-Flore [EA4483, Université de Lille 2, Faculté de Médecine de Lille, Pôle Recherche, 59045 Lille (France); Service de Néphrologie, Hôpital Huriez, Centre Hospitalier Régional Universitaire de Lille, 59037 Lille (France); Perrais, Michaël [Institut National de la Santé et de la Recherche Médicale, UMR837, Centre de Recherche Jean-Pierre Aubert, Equipe 5, 59045 Lille (France); and others

2014-09-15

Numerous xenobiotics have been shown to be harmful for the kidney. Thus, to improve our knowledge of the cellular processing of these nephrotoxic compounds, we evaluated, by real-time PCR, the mRNA expression level of 377 genes encoding xenobiotic-metabolizing enzymes (XMEs), transporters, as well as nuclear receptors and transcription factors that coordinate their expression in eight normal human renal cortical tissues. Additionally, since several renal in vitro models are commonly used in pharmacological and toxicological studies, we investigated their metabolic capacities and compared them with those of renal tissues. The same set of genes was thus investigated in HEK293 and HK2 immortalized cell lines in commercial primary cultures of epithelial renal cells and in proximal tubular cell primary cultures. Altogether, our data offers a comprehensive description of kidney ability to process xenobiotics. Moreover, by hierarchical clustering, we observed large variations in gene expression profiles between renal cell lines and renal tissues. Primary cultures of proximal tubular epithelial cells exhibited the highest similarities with renal tissue in terms of transcript profiling. Moreover, compared to other renal cell models, Tacrolimus dose dependent toxic effects were lower in proximal tubular cell primary cultures that display the highest metabolism and disposition capacity. Therefore, primary cultures appear to be the most relevant in vitro model for investigating the metabolism and bioactivation of nephrotoxic compounds and for toxicological and pharmacological studies. - Highlights: • Renal proximal tubular (PT) cells are highly sensitive to xenobiotics. • Expression of genes involved in xenobiotic disposition was measured. • PT cells exhibited the highest similarities with renal tissue.

Long-term treatment with tenofovir in Asian-American chronic hepatitis B patients is associated with abnormal renal phosphate handling.

Science.gov (United States)

Tien, Connie; Xu, Jason J; Chan, Linda S; Chang, Mimi; Lim, Carolina; Lee, Sue; Huh, Brian; Shinada, Shuntaro; Bae, Ho S; Fong, Tse-Ling

2015-02-01

Increased risk of defective urinary phosphate reabsorption and osteoporosis has been reported in HIV and chronic hepatitis B (CHB) patients treated with tenofovir disoproxil fumarate (TDF). Goals of this study were to evaluate the prevalence of renal phosphate wasting and abnormal bone mineral density in CHB patients taking TDF compared to CHB patients treated with entecavir (ETV) and untreated CHB patients. This is a cross-sectional study of 146 consecutive Asian-American CHB patients who were treatment naïve (n = 60) or treated with either TDF (n = 42) or ETV (n = 44). Proximal tubular handling of phosphate was assessed by the maximal rate of tubular reabsorption of phosphate (TmPO4) divided by glomerular filtration rate (GFR) (TmPO4/GFR). Bone mineral density (BMD) was measured using dual X-ray absorptiometry. TmPO4/GFR was similar among CHB patients treated with TDF compared to untreated patients and patients taking ETV. However, among patients treated with ≥18 months of TDF or ETV, prevalence of abnormal TmPO4/GFR was higher among patients treated with TDF compared to ETV (48.5 % (16/33) vs. 12.5 % (3/24), p = 0.005). Overall prevalence of osteoporosis in this cohort of CHB patients was 14 %, with no significant difference between the three groups. Renal phosphate handling did not correlate with osteoporosis. Chronic hepatitis B patients treated with ≥18 months of TDF experienced an increased risk of proximal tubular dysfunction. TDF did not increase the risk of osteoporosis. Longitudinal studies are needed to confirm these findings.

Regulation of Mg2+ Reabsorption and Transient Receptor Potential Melastatin Type 6 Activity by cAMP Signaling.

NARCIS (Netherlands)

Blanchard, M.G.; Kittikulsuth, W.; Nair, A.V.; Baaij, J.H.F. de; Latta, F.; Genzen, J.R.; Kohan, D.E.; Bindels, R.J.M.; Hoenderop, J.G.J.

2016-01-01

The transient receptor potential melastatin type 6 (TRPM6) epithelial Mg(2+) channels participate in transcellular Mg(2+) transport in the kidney and intestine. Previous reports suggested a hormonal cAMP-dependent regulation of Mg(2+) reabsorption in the kidney. The molecular details of this process

Individual renal function study using dynamic computed tomography

International Nuclear Information System (INIS)

Fukuda, Yutaka; Kiya, Keiichi; Suzuki, Yoshiharu

1990-01-01

Dynamic CT scans of individual kindneys were obtained after an intravenous bolus injection of contrast agent. Time-density curves measured from the renal cortex, medulla and pelvis revealed the changes in density produced by the contrast agent reflecting the differential phase of renal function. Renal cortical density increased rapidly after bolus administration and then renal medullary and pelvic density increased continuously. In analyzing time-density curve, the cortico-medullary junction time, which is the time when the cortical and medullary curves cross was 57±8 seconds in patients with normal renal function. The cortico-medullary junction time was delayed in patient with decreased glomerular filtration rate. The cortico-pelvic junction time, which is the time when the cortical and pelvic curves cross was 104±33 seconds in patients with normal renal function. The cortico-pelvic junction time was delayed in patients with declined urinary concentrating capacity. In patients with unilateral renal agenesis and patients who were treated surgically by ureteral sprits, the relationship between individual renal functions and these junction times was examined. As a result of study there were inversely significant correlations between C-M junction time and unilateral GFR and between C-P junction time and urinary concentrating capacity. These studies indicate that dynamic CT scanning is an effective way that individual renal function can be monitored and evaluated. (author)

Zero-reabsorption doped-nanocrystal luminescent solar concentrators.

Science.gov (United States)

Erickson, Christian S; Bradshaw, Liam R; McDowall, Stephen; Gilbertson, John D; Gamelin, Daniel R; Patrick, David L

2014-04-22

Optical concentration can lower the cost of solar energy conversion by reducing photovoltaic cell area and increasing photovoltaic efficiency. Luminescent solar concentrators offer an attractive approach to combined spectral and spatial concentration of both specular and diffuse light without tracking, but they have been plagued by luminophore self-absorption losses when employed on practical size scales. Here, we introduce doped semiconductor nanocrystals as a new class of phosphors for use in luminescent solar concentrators. In proof-of-concept experiments, visibly transparent, ultraviolet-selective luminescent solar concentrators have been prepared using colloidal Mn(2+)-doped ZnSe nanocrystals that show no luminescence reabsorption. Optical quantum efficiencies of 37% are measured, yielding a maximum projected energy concentration of ∼6× and flux gain for a-Si photovoltaics of 15.6 in the large-area limit, for the first time bounded not by luminophore self-absorption but by the transparency of the waveguide itself. Future directions in the use of colloidal doped nanocrystals as robust, processable spectrum-shifting phosphors for luminescent solar concentration on the large scales required for practical application of this technology are discussed.

Kidney in diabetes: from organ damage target to therapeutic target.

Science.gov (United States)

Salvatore, Teresa; Carbonara, Ornella; Cozzolino, Domenico; Torella, Roberto; Nasti, Rodolfo; Lascar, Nadia; Sasso, Ferdinando Carlo

2011-09-01

Despite the growing of pharmacological options for the treatment of diabetes, epidemiological studies suggest that a substantial proportion of patients does not achieve glycemic goals and so suffers from the risk of chronic complications. This review explores the inhibition of renal glucose reabsorption as a novel approach to treat hyperglycemia. Sodium-glucose cotransporter 2 (SGLT2), a low-affinity high-capacity transporter located in the brush-border membrane of the early segment (S1) of the proximal renal tubule, accounts for about 90% of the reabsorption of glucose from tubular fluid. Competitive inhibitors of SGLT2 that are responsible for renal excretion of glucose provide a unique mechanism to potentially lower the elevated blood glucose levels in patients with diabetes. They act independently of insulin secretion, thereby minimizing the risk of hypoglycemia and weight gain, to control energy balance in a negative direction, a distinctive advantage of this class of drugs over existing oral hypoglycemic agents. Although this group of medications is still under investigation, it appears to be safe and generally well tolerated and it would be expected to improve the treatment of type 2 diabetes as monotherapy or in combination with other oral or parenteral agents. Dapagliflozin is the first agent within this class, which induces clinically meaningful reductions in FPG, PPG, HbA1c, and body weight in type 2 diabetes.

The cytochrome P-450 inhibitor cobalt chloride prevents inhibition of renal Na,K-ATPase and redistribution of apical NHE-3 during acute hypertension

DEFF Research Database (Denmark)

Zhang, Y B; Magyar, C E; Holstein-Rathlou, N H

1998-01-01

by cobalt chloride (CoCl2). Four groups of rats (n = 4 to 5) were studied: (1) sham-operated; (2) 50 mg of CoCl2/kg subcutaneously for 2 d; (3) acute hypertension by constricting arteries for 5 min; and (4) acute hypertension after CoCl2 treatment as in group 3. Renal cortex was analyzed after sorbitol...... reabsorption and diuresis and abolishes Na,K-ATPase inhibition and NHE-3 redistribution during acute hypertension, evidence that these responses may be mediated by cytochrome P-450 arachidonate metabolites....

Significant impact of transient deterioration of renal function on dosimetry in PRRT

International Nuclear Information System (INIS)

Van Binnebeek, S.; Baete, K.; Terwinghe, C.

2013-01-01

Peptide receptor radionuclide therapy (PRRT), with 90 Y-DOTATOC and 177 Lu-DOTATATE as most clinically used radiopeptides, is widely used in the management of metastatic neuroendocrine tumors. With respect to radiation dosimetry, the kidneys are the critical organ for 90 Y-DOTATOC. Renal irradiation is significant because of reabsorption of the radiopeptide from the proximal tubuli and the resulting retention in the interstitium, mainly in the inner cortical zone. The high energy and consequently wide range in tissue of the yttrium-90 beta particle result in high absorbed doses to the kidney cortex and medulla. Accurate renal dosimetry can help minimizing radiation nephropathy. We report a case of a 69-year-old candidate for PRRT with an acceptable kidney function at the time of screening. When performing 111 In-octreotide pretreatment dosimetry 3 weeks later, we observed a drastic deterioration in kidney function, caused by undisclosed non-steroidal anti-inflammatory drug intake. The calculated kidney biological effective dose (BED) was 153 Gy after four projected cycles. PRRT was canceled as our full-course BED limit is 37 Gy and the patient was switched to morphine analgesics. Renal function normalized after 3 months and repeated dosimetry yielded an acceptable kidney BED of 28 Gy after four projected cycles (7 Gy/cycle). This case emphasizes that acute kidney insufficiency can yield toxic kidney doses in a single therapy cycle, with an inherent risk of persistent renal insufficiency. All clinical factors which might influence kidney function should be verified at screening and before PRRT administration. (author)

Approaching to DM2 through sodium-glucose cotransporter-2: does it make sense?

Science.gov (United States)

Segura, Julián

2016-11-01

The kidney is involved in glucose homeostasis through three main mechanisms: renal gluconeogenesis, renal glucose consumption and glucose reabsorption in the proximal tubule. Glucose reabsorption is one of the most relevant physiological functions of the kidney, through which filtered glucose is fully recovered, urine is free of glucose, and calorie loss is prevented. Approximately 90% of the glucose is reabsorbed in the S1 segment of the proximal tubule, where GLUT2 and SGLT2 transporters are located, while the remaining 10% is reabsorbed in the S3 segment by SGLT1 and GLUT1 transporters. In patients with hyperglycaemia, the kidney continues reabsorbing glucose, and hyperglycaemia is maintained. Most renal glucose reabsorption is mediated by the SGLT2 transporter. Several experimental and clinical studies suggest that pharmacological blockade of this transporter might be beneficial in the management of hyperglycemia in patients with type 2 diabetes. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

[Contribution of the kidney to glucose homeostasis].

Science.gov (United States)

Segura, Julián; Ruilope, Luis Miguel

2013-09-01

The kidney is involved in glucose homeostasis through three major mechanisms: renal gluconeogenesis, renal glucose consumption, and glucose reabsorption in the proximal tubule. Glucose reabsorption is one of the most important physiological functions of the kidney, allowing full recovery of filtered glucose, elimination of glucose from the urine, and prevention of calorie loss. Approximately 90% of the glucose is reabsorbed in the S1 segment of the proximal tubule, where glucose transporter-2 (GLUT2) and sodium-glucose transporter-2 (SGLT2) are located, while the remaining 10% is reabsorbed in the S3 segment by SGLT1 and GLUT1 transporters. In patients with hyperglycemia, the kidney continues to reabsorb glucose, thus maintaining hyperglycemia. Most of the renal glucose reabsorption is mediated by SGLT2. Several experimental and clinical studies suggest that pharmacological blockade of this transporter might be beneficial in the management of hyperglycemia in patients with type 2 diabetes. Copyright © 2013 Elsevier España, S.L. All rights reserved.

TRPV5: an ingeniously controlled calcium channel.

NARCIS (Netherlands)

Groot, T. de; Bindels, R.J.M.; Hoenderop, J.G.J.

2008-01-01

Body Ca(2+) homeostasis is tightly controlled and slight disturbances in renal Ca(2+) reabsorption can lead to excessive urine Ca(2+) excretion and promote kidney stone formation. The epithelial Ca(2+) channel TRPV5 constitutes the rate-limiting step of active Ca(2+) reabsorption in the kidney.

Successful Management of Repetitive Urinary Obstruction and Anuria Caused by Double J Stent Calculi Formation after Renal Transplantation

Directory of Open Access Journals (Sweden)

Zongyao Hao

2014-01-01

Full Text Available This report firstly describes an extremely rare case of repetitive double J stent calculi formation after renal transplantation caused by the antihyperparathyroidism (HPT drug calcitriol. In 2012, a woman initially presented to our hospital for anuria with lower abdominal pain. She was diagnosed with allograft hydronephrosis and double J stents obstruction by calculi formation after transplantation and treated with triplicate stents replacements in another hospital without clinical manifestations improvements. Through detailed exploration of medical history, we conclude that the abnormal calculi formation is due to the calcitriol (1,25-dihydroxyvitamin D3 administration, a drug which can increase renal tubular reabsorption of calcium for treating posttransplant HPT bone disease. After discontinuing calcitriol, the patient was stone-free and had a good recovery without severe complications during the 9-month follow-up. Our novel findings may provide an important clue and approach to managing formidable repetitive double J stent calculi formation in the clinical trial.

A novel member of the trehalose transporter family functions as an H+-dependent trehalose transporter in the reabsorption of trehalose in Malpighian tubules.

Directory of Open Access Journals (Sweden)

Shingo eKikuta

2012-07-01

Full Text Available In insects, Malpighian tubules are functionally analogous to mammalian kidneys in that they not only are essential to excrete waste molecules into the lumen but also are responsible for the reabsorption of indispensable molecules, such as sugars, from the lumen to the principal cells. Among sugars, the disaccharide trehalose is highly important to insects because it is the main hemolymph sugar to serve as a source of energy and carbon. The trehalose transporter TRET1 participates in the transfer of newly synthesized trehalose from the fat body across the cellular membrane into the hemolymph. Although transport proteins must play a pivotal role in the reabsorption of trehalose in Malpighian tubules, the molecular context underlying this process remains obscure. Previously, we identified a Tret1 homolog (Nlst8 that is expressed principally in the Malpighian tubules of the brown planthopper (BPH. Here, we used the Xenopus oocyte expression system to show that NlST8 exerts trehalose transport activity that is elevated under low pH conditions. These functional assays indicate that Nlst8 encodes a proton-dependent trehalose transporter (H-TRET1. To examine the involvement of Nlst8 in trehalose reabsorption, we analyzed the sugar composition of honeydew by using BPH with RNAi gene silencing. Trehalose was detected in the honeydew as waste excreted from Nlst8-dsRNA-injected BPH under hyperglycemic conditions. However, trehalose was not expelled from GFP-dsRNA-injected BPH even under hyperglycemic conditions. We conclude that NlST8 could participate in trehalose reabsorption driven by a H+ gradient from the lumen to the principal cells of the Malpighian tubules.

Evaluation of oxidative stress status and antioxidant capacity in patients with renal cell carcinoma.

Science.gov (United States)

Aldemir, Mustafa; Karaguzel, Ersagun; Okulu, Emrah; Gudeloglu, Ahmet; Ener, Kemal; Ozayar, Asim; Erel, Ozcan

2015-01-01

We evaluated and compared the serum oxidative stress and antioxidant enzymes in patients with renal cell carcinoma (RCC) and the control group. The prospective study consisted of 97 patients with RCC (Group 1) and 80 age and sex matched healthy volunteers (Group 2). Group 1 and 2 were compared concerning serum mean total oxidant status (TOS), total antioxidant capacity (TAC), paraoxonase-1 (PON-1), arylesterase, total thiol, catalase (CAT), myeloperoxidase (MPO) and ceruloplasmin. Patients' mean age was 58.5 ±12.3 and 56.9 ±15.8 years, respectively, in Group 1 and 2. No statistically significant differences were detected between the groups in terms of oxidative stress parameters and antioxidant capacity measured in the serum of patients including, TOS, TAC, PON1, arylesterase, total thiol, CAT, MPO, and ceruloplasmin levels (p >0.05 for all parameters). The PON-1 value was significantly higher in patients with pT1 stage than pT3 stage (p = 0.007). The arylesterase value was significantly higher in patients with Fuhrman's nuclear grade 3 than grade 2 (p = 0.035). There was no correlation between these parameters level and Fuhrman's nuclear grade, stage, or histopathological tumor type. Our results demonstrated that evaluation of these parameters in the serum of patients with localized RCC may not be used as a marker to discriminate between patients with RCC and healthy people.

A bioartificial renal tubule device embedding human renal stem/progenitor cells.

Directory of Open Access Journals (Sweden)

Anna Giovanna Sciancalepore

Full Text Available We present a bio-inspired renal microdevice that resembles the in vivo structure of a kidney proximal tubule. For the first time, a population of tubular adult renal stem/progenitor cells (ARPCs was embedded into a microsystem to create a bioengineered renal tubule. These cells have both multipotent differentiation abilities and an extraordinary capacity for injured renal cell regeneration. Therefore, ARPCs may be considered a promising tool for promoting regenerative processes in the kidney to treat acute and chronic renal injury. Here ARPCs were grown to confluence and exposed to a laminar fluid shear stress into the chip, in order to induce a functional cell polarization. Exposing ARPCs to fluid shear stress in the chip led the aquaporin-2 transporter to localize at their apical region and the Na(+K(+ATPase pump at their basolateral portion, in contrast to statically cultured ARPCs. A recovery of urea and creatinine of (20±5% and (13±5%, respectively, was obtained by the device. The microengineered biochip here-proposed might be an innovative "lab-on-a-chip" platform to investigate in vitro ARPCs behaviour or to test drugs for therapeutic and toxicological responses.

Controlling reabsorption effect of bi-color CdSe quantum dots-based white light-emitting diodes

Science.gov (United States)

Siao, Cyuan-Bin; Chung, Shu-Ru; Wang, Kuan-Wen

2017-08-01

The colloidal semiconductor quantum dots (QDs) have the potentials to be used in white light-emitting diode (WLED) as a down-converting component to replace incandescent lamps, because the traditional WLED composed of Y3Al5O12:Ce3+ (YAG:Ce) phosphor lack of red color emissions and shows low color quality. Among various QDs, CdSe has been extensively studied because it possesses attractive characteristics such as high quantum yields (QYs), narrow emission spectral bandwidth, as well as size-tunable optical characteristics. However, in order to enhance the color rendering index (CRI) of WLED, blending materials with different emission wavelengths has been used frequently. Unfortunately, these procedures are complex and time-consuming, and the emission energy of smaller QDs can be reabsorbed by larger QDs, resulting in decreasing the excitation intensity in yellowish-green region. Therefore, in this study, in order to decrease the reabsorption effect and to simplify the procedures, we have demonstrated a facile thermal pyrolyzed route to prepare bicolor CdSe QDs with dual-wavelengths. The emission wavelengths, particle sizes, and QYs of QDs can be tuned from 537/595 to 537/602 nm, 2.59/3.92 to 2.59/4.01 nm, and 27 to 40 %, for GR1 to 3 samples, respectively when the amount of Se precursor is decreased from 1.5 to 0.75 mmol. Meanwhile, the area ratio of green to red (Ag/Ar) in fluorescence spectra is gradually increased, due to the increase in growth rate, and decrease in nuclei formation in red emission. The GR1, GR2, and GR3 QDs are then encapsulated by convert types to form the LED, in which the QDs are deposited on the blue-emitting InGaN LED chip (λem = 450 nm). After encapsulation, the devices properties of Commission International d'Eclairage (CIE) chromaticity and Ag/Ar area ratio are (0.40, 0.24), 0.28/1, (0.40, 0.31), 0.52/1, and (0.40, 0.38), 1.02/1, respectively for GR1, GR2, and GR3. The results show that the green emission intensity are strongly

Cyclophilin B expression in renal proximal tubules of hypertensive rats.

Science.gov (United States)

Kainer, D B; Doris, P A

2000-04-01

Rat cyclophilin-like protein (Cy-LP) is a candidate hypertension gene initially identified by differential hybridization and implicated in renal mechanisms of salt retention and high blood pressure. We report the molecular characterization of rat cyclophilin B (CypB) and demonstrate, through sequence analysis and an allele-specific polymerase chain reaction primer assay, that CypB but not Cy-LP is expressed in rat kidney. CypB is an endoplasmic reticulum-localized prolyl-isomerase that interacts with elongation initiation factor 2-beta, an important regulator of protein translation and a central component of the endoplasmic reticulum stress response to hypoxia or ATP depletion. Active renal transport of sodium is increased in the spontaneously hypertensive rat (SHR), and there is evidence that this coincides with hypoxia and ATP depletion in the renal cortex. In the present studies we have examined expression of CypB in rat proximal tubules, which contributes to the increased renal sodium reabsorption in this model of hypertension. We report that CypB transcript abundance is significantly elevated in proximal convoluted tubules from SHR compared with the control Wistar-Kyoto strain. This upregulation occurs in weanling animals and precedes the development of hypertension, indicating that it is not a simple response to hypertension in SHR. Further, CypB expression is also higher in a proximal tubule cell line derived from SHR compared with a similar line derived from Wistar-Kyoto rats, indicating that this difference is genetically determined. No sequence differences were observed in the CypB cDNA from these 2 strains. These observations suggest that a genetically determined alteration in proximal tubules from SHR occurs that leads to increased expression of CypB. In view of evidence linking CypB to the regulation of elongation initiation factor-2, the upregulation of CypB may result from metabolic stress.

Dynamic autoregulation and renal injury in Dahl rats

DEFF Research Database (Denmark)

Karlsen, F M; Andersen, C B; Leyssac, P P

1997-01-01

of hypertension, a gradual impairment of autoregulatory control of renal blood flow might expose the glomerular circulation to periods of elevated pressure, resulting in renal injuries in Dahl S rats. Dynamic autoregulatory capacity was assessed in Dahl S and Dahl salt-resistant (Dahl R) rats, SHR, and Sprague......-Dawley rats by inducing broad-band fluctuations in the arterial blood pressure and simultaneously measuring renal blood flow. Dynamic autoregulation was estimated by the transfer function using blood pressure as the input and renal blood flow as the output. Renal morphological injuries were evaluated in Dahl......The Dahl salt-sensitive (Dahl S) rat develops hypertension and renal injuries when challenged with a high salt diet and has been considered to be a model of chronic renal failure. Renal injuries appear very early in life compared with the spontaneously hypertensive rat (SHR). During the course...

Renal response to L-arginine in diabetic rats. A possible link between nitric oxide system and aquaporin-2.

Directory of Open Access Journals (Sweden)

María C Ortiz

Full Text Available The aim of this study was to evaluate whether L-Arginine (L-Arg supplementation modifies nitric oxide (NO system and consequently aquaporin-2 (AQP2 expression in the renal outer medulla of streptozotocin-diabetic rats at an early time point after induction of diabetes. Male Wistar rats were divided in four groups: Control, Diabetic, Diabetic treated with L-Arginine and Control treated with L-Arginine. Nitric oxide synthase (NOS activity was estimated by [14C] L-citrulline production in homogenates of the renal outer medulla and by NADPH-diaphorase staining in renal outer medullary tubules. Western blot was used to detect the expression of AQP2 and NOS types I and III; real time PCR was used to quantify AQP2 mRNA. The expression of both NOS isoforms, NOS I and NOS III, was decreased in the renal outer medulla of diabetic rats and L-Arg failed to prevent these decreases. However, L-Arg improved NO production, NADPH-diaphorase activity in collecting ducts and other tubular structures, and NOS activity in renal homogenates from diabetic rats. AQP2 protein and mRNA were decreased in the renal outer medulla of diabetic rats and L-Arg administration prevented these decreases. These results suggest that the decreased NOS activity in collecting ducts of the renal outer medulla may cause, at least in part, the decreased expression of AQP2 in this model of diabetes and constitute additional evidence supporting a role for NO in contributing to renal water reabsorption through the modulation of AQP2 expression in this pathological condition. However, we cannot discard that another pathway different from NOS also exists that links L-Arg to AQP2 expression.

Reversal of Proximal Renal Tubular Dysfunction after Nucleotide Analogue Withdrawal in Chronic Hepatitis B

Directory of Open Access Journals (Sweden)

Abhasnee Sobhonslidsuk

2017-01-01

Full Text Available Aims. Proximal renal tubular dysfunction (PRTD is an infrequent complication after nucleotide analogue therapy. We evaluated the outcomes of PRTD and nephrotoxicity after nucleotide analogue withdrawal in chronic hepatitis B (CHB. Methods. A longitudinal follow-up study was performed in patients with PRTD after nucleotide analogue discontinuation. Serum and urine were collected at baseline and every 3 months for one year. The fractional excretion of phosphate (PO4, uric acid (UA, and potassium and tubular maximal reabsorption rate of PO4 to glomerular filtration rate (TmPO4/GFR were calculated. Renal losses were defined based on the criteria of substance losses. Subclinical PRTD and overt PRTD were diagnosed when 2 and ≥3 criteria were identified. Results. Eight subclinical and eight overt PRTD patients were enrolled. After nucleotide analogue withdrawal, there were overall improvements in GFR, serum PO4, and UA. Renal loss of PO4, UA, protein, and β2-microglobulin reduced over time. At one year, complete reversal of PRTD was seen in 13 patients (81.2%. Improvements in PRTD were seen in all but one patient. Conclusion. One year after nucleotide analogue withdrawal, PRTD was resolved in most patients. Changes in TmPO4/GFR, urinary protein, and β2-microglobulin indicate that urinary biomarkers may represent an early sign of PRTD recovery.

Ion transporters for fluid reabsorption in the rooster (Gallus domesticus) epididymal region.

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Bahr, J M; Dalponte, M; Janssen, S; Bunick, D; Nakai, M

2006-10-01

Testicular fluid is highly condensed during its passage through the epididymal region in the avian species. In the present study, major ion transporters that are responsible for condensation mainly by water resorption in the reproductive tract as identified in the mammalian epididymis were localized within the rooster (Gallus domesticus) epididymis by immunohistochemistry. The results show that the efferent ductule epithelium expressed sodium-potassium ATPase (Na(+),K(+)-ATPase), carbonic anhydrase II (CAII) and sodium hydrogen exchanger isoform 3 (NHE3) and that the connecting ductule and epididymal duct epithelia expressed Na(+),K(+)-ATPase and CAII. These data suggest that a model proposed for reabsorption in mammalian efferent ductules can be applied to avian efferent ductules.

Effect of diuretics on renal tubular transport of calcium and magnesium.

Science.gov (United States)

Alexander, R Todd; Dimke, Henrik

2017-06-01

Calcium (Ca 2+ ) and Magnesium (Mg 2+ ) reabsorption along the renal tubule is dependent on distinct trans- and paracellular pathways. Our understanding of the molecular machinery involved is increasing. Ca 2+ and Mg 2+ reclamation in kidney is dependent on a diverse array of proteins, which are important for both forming divalent cation-permeable pores and channels, but also for generating the necessary driving forces for Ca 2+ and Mg 2+ transport. Alterations in these molecular constituents can have profound effects on tubular Ca 2+ and Mg 2+ handling. Diuretics are used to treat a large range of clinical conditions, but most commonly for the management of blood pressure and fluid balance. The pharmacological targets of diuretics generally directly facilitate sodium (Na + ) transport, but also indirectly affect renal Ca 2+ and Mg 2+ handling, i.e., by establishing a prerequisite electrochemical gradient. It is therefore not surprising that substantial alterations in divalent cation handling can be observed following diuretic treatment. The effects of diuretics on renal Ca 2+ and Mg 2+ handling are reviewed in the context of the present understanding of basal molecular mechanisms of Ca 2+ and Mg 2+ transport. Acetazolamide, osmotic diuretics, Na + /H + exchanger (NHE3) inhibitors, and antidiabetic Na + /glucose cotransporter type 2 (SGLT) blocking compounds, target the proximal tubule, where paracellular Ca 2+ transport predominates. Loop diuretics and renal outer medullary K + (ROMK) inhibitors block thick ascending limb transport, a segment with significant paracellular Ca 2+ and Mg 2+ transport. Thiazides target the distal convoluted tubule; however, their effect on divalent cation transport is not limited to that segment. Finally, potassium-sparing diuretics, which inhibit electrogenic Na + transport at distal sites, can also affect divalent cation transport. Copyright © 2017 the American Physiological Society.

Thiazolidinediones and Edema: Recent Advances in the Pathogenesis of Thiazolidinediones-Induced Renal Sodium Retention.

Science.gov (United States)

Horita, Shoko; Nakamura, Motonobu; Satoh, Nobuhiko; Suzuki, Masashi; Seki, George

2015-01-01

Thiazolidinediones (TZDs) are one of the major classes of antidiabetic drugs that are used widely. TZDs improve insulin resistance by activating peroxisome proliferator-activated receptor gamma (PPARγ) and ameliorate diabetic and other nephropathies, at least, in experimental animals. However, TZDs have side effects, such as edema, congestive heart failure, and bone fracture, and may increase bladder cancer risk. Edema and heart failure, which both probably originate from renal sodium retention, are of great importance because these side effects make it difficult to continue the use of TZDs. However, the pathogenesis of edema remains a matter of controversy. Initially, upregulation of the epithelial sodium channel (ENaC) in the collecting ducts by TZDs was thought to be the primary cause of edema. However, the results of other studies do not support this view. Recent data suggest the involvement of transporters in the proximal tubule, such as sodium-bicarbonate cotransporter and sodium-proton exchanger. Other studies have suggested that sodium-potassium-chloride cotransporter 2 in the thick ascending limb of Henle and aquaporins are also possible targets for TZDs. This paper will discuss the recent advances in the pathogenesis of TZD-induced sodium reabsorption in the renal tubules and edema.

Lithium clearance in chronic nephropathy

DEFF Research Database (Denmark)

Kamper, A L; Holstein-Rathlou, N H; Leyssac, P P

1989-01-01

1. Lithium clearance measurements were made in 72 patients with chronic nephropathy of different aetiology and moderate to severely reduced renal function. 2. Lithium clearance was strictly correlated with glomerular filtration rate, and there was no suggestion of distal tubular reabsorption...... of lithium or influence of osmotic diuresis. 3. Fractional reabsorption of lithium was reduced in most patients with glomerular filtration rates below 25 ml/min. 4. Calculated fractional distal reabsorption of sodium was reduced in most patients with glomerular filtration rates below 50 ml/min. 5. Lithium...... that lithium clearance may be a measure of the delivery of sodium and water from the renal proximal tubule. With this assumption it was found that adjustment of the sodium excretion in chronic nephropathy initially takes place in the distal parts of the nephron (loop of Henle, distal tubule and collecting duct...

alpha-Adducin mutations increase Na/K pump activity in renal cells by affecting constitutive endocytosis: implications for tubular Na reabsorption.

Science.gov (United States)

Torielli, Lucia; Tivodar, Simona; Montella, Rosa Chiara; Iacone, Roberto; Padoani, Gloria; Tarsini, Paolo; Russo, Ornella; Sarnataro, Daniela; Strazzullo, Pasquale; Ferrari, Patrizia; Bianchi, Giuseppe; Zurzolo, Chiara

2008-08-01

Genetic variation in alpha-adducin cytoskeletal protein is implicated in the polymerization and bundling of actin and alteration of the Na/K pump, resulting in abnormal renal sodium transport and hypertension in Milan hypertensive rats and humans. To investigate the molecular involvement of alpha-adducin in controlling Na/K pump activity, wild-type or mutated rat and human alpha-adducin forms were, respectively, transfected into several renal cell lines. Through multiple experimental approaches (microscopy, enzymatic assays, coimmunoprecipitation), we showed that rat and human mutated forms increased Na/K pump activity and the number of pump units; moreover, both variants coimmunoprecipitate with Na/K pump. The increased Na/K pump activity was not due to changes in its basolateral localization, but to an alteration of Na/K pump residential time on the plasma membrane. Indeed, both rat and human mutated variants reduced constitutive Na/K pump endocytosis and similarly affected transferrin receptor trafficking and fluid-phase endocytosis. In fact, alpha-adducin was detected in clathrin-coated vesicles and coimmunoprecipitated with clathrin. These results indicate that adducin, besides its modulatory effects on actin cytoskeleton dynamics, might play a direct role in clathrin-dependent endocytosis. The constitutive reduction of the Na/K pump endocytic rate induced by mutated adducin variants may be relevant in Na-dependent hypertension.

H+, Water and Urea Transport in the Inner Medullary Collecting Duct and Their Role in the Prevention and Pathogenesis of Renal Stone Disease

Science.gov (United States)

Wall, Susan M.; Klein, Janet D.

2008-09-01

The inner medullary collecting duct (IMCD) is the final site within the kidney for the reabsorption of urea, water and electrolytes and for the secretion of H+ before the luminal fluid becomes the final urine. Transporters expressed in the IMCD contribute to the generation of the large ion gradients that exist between the interstitium and the collecting duct lumen. Thus, the luminal fluid within the human IMCD can reach an osmolality of 1200 mOsm/kg H2O and a pH of 4. This ability of the human nephron to concentrate and acidify the urine might predispose to stone formation. However, under treatment conditions that predispose to stone formation, such as during hypercalciuria, the kidney mitigates stone formation by reducing solute concentration by reducing H2O reabsorption. Moreover, the kidney attenuates stone formation by tightly controlling acid-base balance, which prevents the bone loss, hypocitraturia and hypercalciuria observed during metabolic acidosis by augmenting net H+ excretion by tightly regulating H+ transporter function and through luminal buffering, particularly with NH3. This article will review the ion transporters present in the mammalian IMCD and their role in the prevention and in the pathogenesis of renal stone formation.

CD47 regulates renal tubular epithelial cell self-renewal and proliferation following renal ischemia reperfusion.

Science.gov (United States)

Rogers, Natasha M; Zhang, Zheng J; Wang, Jiao-Jing; Thomson, Angus W; Isenberg, Jeffrey S

2016-08-01

Defects in renal tubular epithelial cell repair contribute to renal ischemia reperfusion injury, cause acute kidney damage, and promote chronic renal disease. The matricellular protein thrombospondin-1 and its receptor CD47 are involved in experimental renal ischemia reperfusion injury, although the role of this interaction in renal recovery is unknown. We found upregulation of self-renewal genes (transcription factors Oct4, Sox2, Klf4 and cMyc) in the kidney of CD47(-/-) mice after ischemia reperfusion injury. Wild-type animals had minimal self-renewal gene expression, both before and after injury. Suggestive of cell autonomy, CD47(-/-) renal tubular epithelial cells were found to increase expression of the self-renewal genes. This correlated with enhanced proliferative capacity compared with cells from wild-type mice. Exogenous thrombospondin-1 inhibited self-renewal gene expression in renal tubular epithelial cells from wild-type but not CD47(-/-) mice, and this was associated with decreased proliferation. Treatment of renal tubular epithelial cells with a CD47 blocking antibody or CD47-targeting small interfering RNA increased expression of some self-renewal transcription factors and promoted cell proliferation. In a syngeneic kidney transplant model, treatment with a CD47 blocking antibody increased self-renewal transcription factor expression, decreased tissue damage, and improved renal function compared with that in control mice. Thus, thrombospondin-1 via CD47 inhibits renal tubular epithelial cell recovery after ischemia reperfusion injury through inhibition of proliferation/self-renewal. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

The angiotensin type 2 receptor and the kidney

DEFF Research Database (Denmark)

Peluso, Antonio A B; Santos, Robson A S; Unger, Thomas H

2017-01-01

by internalisation of these transporters, thus reducing reabsorption and increasing natriuresis/diuresis. Regarding renal pathology, several studies demonstrated an attenuation of renal injury caused by diabetes or by obesity with or without high-salt diet through anti-inflammatory, antifibrotic, and antioxidative...

Relaxation of atomic state multipoles by radiation re-absorption: Neon 2p2 atoms in a discharge plasma

International Nuclear Information System (INIS)

Nimura, M.; Imagawa, T.; Hasuo, M.; Fujimoto, T.

2005-01-01

In a positive column of a glow discharge in the magnetic field of 36.4G, a linearly polarized laser pulse or a circularly polarized laser pulse has produced polarized neon atoms (alignment or orientation) in the 2p 2 (Paschen notation) level from the 1s 3 level. The subsequent fluorescence to the 1s 2 level was observed with its polarized components resolved. Depopulation, disorientation and disalignment rates of the 2p 2 atom were measured and their discharge current dependences were examined for a discharge current from 0.4 to 2.0mA. The degrees of radiation re-absorption, or the optical thickness, of the transition lines from the 2p 2 level to the 1s 2 -1s 5 levels were measured as functions of the discharge current. A Monte Carlo simulation was performed by which the depopulation, disorientation and disalignment rates by the radiation re-absorption for these transitions were determined. The calculated rates were compared with the observed ones and found to reproduce the their discharge current dependences. D'Yankonov and Perel's analytical expression for these rates was quantified from comparison with the Monte Carlo results

Physical Exercise and Patients with Chronic Renal Failure: A Meta-Analysis.

Science.gov (United States)

Qiu, Zhenzhen; Zheng, Kai; Zhang, Haoxiang; Feng, Ji; Wang, Lizhi; Zhou, Hao

2017-01-01

Chronic renal failure is a severe clinical problem which has some significant socioeconomic impact worldwide and hemodialysis is an important way to maintain patients' health state, but it seems difficult to get better in short time. Considering these, the aim in our research is to update and evaluate the effects of exercise on the health of patients with chronic renal failure. The databases were used to search for the relevant studies in English or Chinese. And the association between physical exercise and health state of patients with chronic renal failure has been investigated. Random-effect model was used to compare the physical function and capacity in exercise and control groups. Exercise is helpful in ameliorating the situation of blood pressure in patients with renal failure and significantly reduces VO 2 in patients with renal failure. The results of subgroup analyses show that, in the age >50, physical activity can significantly reduce blood pressure in patients with renal failure. The activity program containing warm-up, strength, and aerobic exercises has benefits in blood pressure among sick people and improves their maximal oxygen consumption level. These can help patients in physical function and aerobic capacity and may give them further benefits.

Accounting for oxygen in the renal cortex: a computational study of factors that predispose the cortex to hypoxia.

Science.gov (United States)

Lee, Chang-Joon; Gardiner, Bruce S; Ngo, Jennifer P; Kar, Saptarshi; Evans, Roger G; Smith, David W

2017-08-01

We develop a pseudo-three-dimensional model of oxygen transport for the renal cortex of the rat, incorporating both the axial and radial geometry of the preglomerular circulation and quantitative information regarding the surface areas and transport from the vasculature and renal corpuscles. The computational model was validated by simulating four sets of published experimental studies of renal oxygenation in rats. Under the control conditions, the predicted cortical tissue oxygen tension ([Formula: see text]) or microvascular oxygen tension (µPo 2 ) were within ±1 SE of the mean value observed experimentally. The predicted [Formula: see text] or µPo 2 in response to ischemia-reperfusion injury, acute hemodilution, blockade of nitric oxide synthase, or uncoupling mitochondrial respiration, were within ±2 SE observed experimentally. We performed a sensitivity analysis of the key model parameters to assess their individual or combined impact on the predicted [Formula: see text] and µPo 2 The model parameters analyzed were as follows: 1 ) the major determinants of renal oxygen delivery ([Formula: see text]) (arterial blood Po 2 , hemoglobin concentration, and renal blood flow); 2 ) the major determinants of renal oxygen consumption (V̇o 2 ) [glomerular filtration rate (GFR) and the efficiency of oxygen utilization for sodium reabsorption (β)]; and 3) peritubular capillary surface area (PCSA). Reductions in PCSA by 50% were found to profoundly increase the sensitivity of [Formula: see text] and µPo 2 to the major the determinants of [Formula: see text] and V̇o 2 The increasing likelihood of hypoxia with decreasing PCSA provides a potential explanation for the increased risk of acute kidney injury in some experimental animals and for patients with chronic kidney disease. Copyright © 2017 the American Physiological Society.

Vasopressin, Copeptin, and Renal Concentrating Capacity in Patients with Autosomal Dominant Polycystic Kidney Disease without Renal Impairment

NARCIS (Netherlands)

Zittema, Debbie; Boertien, Wendy E.; van Beek, Andre P.; Dullaart, Robin P. F.; Franssen, Casper F. M.; de Jong, Paul E.; Meijer, Esther; Gansevoort, Ron T.

Background and objectives Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent hereditary renal disease, characterized by cyst formation in the kidneys leading to end stage kidney failure. It is clinically acknowledged that ADPKD patients have impaired urine concentrating

New insights on molecular mechanisms of renal aging.

Science.gov (United States)

Schmitt, R; Melk, A

2012-11-01

Long-term transplant outcome is importantly influenced by the age of the organ donor. The mechanisms how age carries out its pathophysiological impact on graft survival are still not understood. One major contributing factor for the observed poor performance of old donor kidneys seems in particular the age-related loss in renal regenerative capacity. In this review, we will summarize recent findings about the molecular basis of renal aging with specific focus on the potential role of somatic cellular senescence and mitochondrial aging in renal transplant outcome. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.

Thiazolidinediones and Edema: Recent Advances in the Pathogenesis of Thiazolidinediones-Induced Renal Sodium Retention

Directory of Open Access Journals (Sweden)

Shoko Horita

2015-01-01

Full Text Available Thiazolidinediones (TZDs are one of the major classes of antidiabetic drugs that are used widely. TZDs improve insulin resistance by activating peroxisome proliferator-activated receptor gamma (PPARγ and ameliorate diabetic and other nephropathies, at least, in experimental animals. However, TZDs have side effects, such as edema, congestive heart failure, and bone fracture, and may increase bladder cancer risk. Edema and heart failure, which both probably originate from renal sodium retention, are of great importance because these side effects make it difficult to continue the use of TZDs. However, the pathogenesis of edema remains a matter of controversy. Initially, upregulation of the epithelial sodium channel (ENaC in the collecting ducts by TZDs was thought to be the primary cause of edema. However, the results of other studies do not support this view. Recent data suggest the involvement of transporters in the proximal tubule, such as sodium-bicarbonate cotransporter and sodium-proton exchanger. Other studies have suggested that sodium-potassium-chloride cotransporter 2 in the thick ascending limb of Henle and aquaporins are also possible targets for TZDs. This paper will discuss the recent advances in the pathogenesis of TZD-induced sodium reabsorption in the renal tubules and edema.

Physical Exercise and Patients with Chronic Renal Failure: A Meta-Analysis

Science.gov (United States)

Qiu, Zhenzhen; Zheng, Kai; Zhang, Haoxiang; Feng, Ji; Wang, Lizhi

2017-01-01

Chronic renal failure is a severe clinical problem which has some significant socioeconomic impact worldwide and hemodialysis is an important way to maintain patients' health state, but it seems difficult to get better in short time. Considering these, the aim in our research is to update and evaluate the effects of exercise on the health of patients with chronic renal failure. The databases were used to search for the relevant studies in English or Chinese. And the association between physical exercise and health state of patients with chronic renal failure has been investigated. Random-effect model was used to compare the physical function and capacity in exercise and control groups. Exercise is helpful in ameliorating the situation of blood pressure in patients with renal failure and significantly reduces VO2 in patients with renal failure. The results of subgroup analyses show that, in the age >50, physical activity can significantly reduce blood pressure in patients with renal failure. The activity program containing warm-up, strength, and aerobic exercises has benefits in blood pressure among sick people and improves their maximal oxygen consumption level. These can help patients in physical function and aerobic capacity and may give them further benefits. PMID:28316986

Stimulation of renal afferent fibers leads to activation of catecholaminergic and non-catecholaminergic neurons in the medulla oblongata.

Science.gov (United States)

Nishi, Erika E; Martins, Beatriz S; Milanez, Maycon I O; Lopes, Nathalia R; de Melo, Jose F; Pontes, Roberto B; Girardi, Adriana C; Campos, Ruy R; Bergamaschi, Cássia T

2017-05-01

Presympathetic neurons in the rostral ventrolateral medulla (RVLM) including the adrenergic cell groups play a major role in the modulation of several reflexes required for the control of sympathetic vasomotor tone and blood pressure (BP). Moreover, sympathetic vasomotor drive to the kidneys influence natriuresis and diuresis by inhibiting the cAMP/PKA pathway and redistributing the Na + /H + exchanger isoform 3 (NHE3) to the body of the microvilli in the proximal tubules. In this study we aimed to evaluate the effects of renal afferents stimulation on (1) the neurochemical phenotype of Fos expressing neurons in the medulla oblongata and (2) the level of abundance and phosphorylation of NHE3 in the renal cortex. We found that electrical stimulation of renal afferents increased heart rate and BP transiently and caused activation of tyrosine hydroxylase (TH)-containing neurons in the RVLM and non-TH neurons in the NTS. Additionally, activation of the inhibitory renorenal reflex over a 30-min period resulted in increased natriuresis and diuresis associated with increased phosphorylation of NHE3 at serine 552, a surrogate for reduced activity of this exchanger, in the contralateral kidney. This effect was not dependent of BP changes considering that no effects on natriuresis or diuresis were found in the ipsilateral-stimulated kidney. Therefore, our data show that renal afferents leads to activation of catecholaminergic and non-catecholaminergic neurons in the medulla oblongata. When renorenal reflex is induced, NHE3 exchanger activity appears to be decreased, resulting in decreased sodium and water reabsorption in the contralateral kidney. Copyright © 2017 Elsevier B.V. All rights reserved.

Diminished renal urea excretion in the llama at reduced food intake

International Nuclear Information System (INIS)

Engelhardt, W.; Engelhardt, W. von

1976-01-01

At a low protein low-energy diet or during reduced food intake, the glomerular filtration rate and thereby the glomerular filtered urea was reduced by about 30%. During most experiments tubular reabsorption of filtered urea was rather constant (averaging 43%). A high reabsorption of 87% was observed in one llama for several weeks during a straw diet with moderate supplementation of some carbohydrates. (author)

Update on the renal toxicity of iodinated contrast drugs used in clinical medicine

Directory of Open Access Journals (Sweden)

Andreucci M

2017-05-01

Full Text Available Michele Andreucci,1 Teresa Faga,1 Raffaele Serra,2 Giovambattista De Sarro,3 Ashour Michael1 1Renal Unit, Department of Health Sciences, 2Interuniversity Center of Phlebolymphology (CIFL, International Research and Educational Program in Clinical and Experimental Biotechnology, Department of Medical and Surgical Sciences, 3Pharmacology Unit, Department of Health Sciences, Magna Graecia University, Catanzaro, Italy Abstract: An important side effect of diagnostic contrast drugs is contrast-induced acute kidney injury (CI-AKI; a sudden decrease in renal function occurring 48–72 hours after injection of a contrast drug that cannot be attributed to other causes. Its existence has recently been challenged, because of some retrospective studies in which the incidence of AKI was not different between subjects who received a contrast drug and those who did not, even using propensity score matching to prevent selection bias. For some authors, only patients with estimated glomerular filtration rate <30 mL/min/1.73 m2 are at significant risk of CI-AKI. Most agree that when renal function is normal, there is no CI-AKI risk. Many experimental studies, however, are in favor of the existence of CI-AKI. Contrast drugs have been shown to cause the following changes: renal vasoconstriction, resulting in a rise in intrarenal resistance (decrease in renal blood flow and glomerular filtration rate and medullary hypoxia; epithelial vacuolization and dilatation and necrosis of proximal tubules; potentiation of angiotensin II effects, reducing nitric oxide (NO and causing direct constriction of descending vasa recta, leading to formation of reactive oxygen species in isolated descending vasa recta of rats microperfused with a solution of iodixanol; increasing active sodium reabsorption in the thick ascending limbs of Henle’s loop (increasing O2 demand and consequently medullary hypoxia; direct cytotoxic effects on endothelial and tubular epithelial cells (decrease

Effects of aging on renal function and regenerative capacity.

Science.gov (United States)

Abdel-Rahman, Emaad M; Okusa, Mark D

2014-01-01

Along with the increase in aging of our population, the proportion of older patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD) is on the rise as a result of the accumulation of comorbidities as well as biological processes associated with aging. Older patients with acute kidney injury (AKI) comprise an increasing proportion of patients with CKD/ESRD as well. In this review, we will discuss biological processes of aging that predispose patients to AKI and CKD. 2014 S. Karger AG, Basel.

Increased renal adrenomedullin expression in rats with ureteral obstruction

DEFF Research Database (Denmark)

Nørregaard, Rikke; Bødker, Tina; Jensen, Boye L

2009-01-01

Ureteral obstruction is characterized by decreased renal blood flow that is associated with hypoxia within the kidney. Adrenomedullin (AM) is a peptide hormone with tissue-protective capacity that is stimulated through hypoxia. We tested the hypothesis that ureteral obstruction stimulates...... increases in response to ureteral obstruction in agreement with expected oxygen gradients. Hypoxia acting through HIF-1alpha accumulation may be an important pathway for the renal response to ureteral obstruction....

Endogenous versus exogenous lithium clearance for evaluation of dopamine-induced changes in renal tubular function

DEFF Research Database (Denmark)

Olsen, Niels Vidiendal; Fogh-Andersen, N; Strandgaard, S

1996-01-01

1. The present randomized, double-blind cross-over study compared endogenous and exogenous lithium clearance (CLi) for estimation of the effect of dopamine on tubular sodium reabsorption. Twelve normal, salt-repleted male subjects were investigated on three different occasions with either placebo...... or 450 mg or 600 mg of lithium given in random order at 22.00 hours. After an overnight fast, renal clearance studies were performed during a 1 h baseline period and subsequently during the second hour of an infusion of 3 micrograms min-1 kg-1 of dopamine. 2. Baseline values of endogenous CLi.......3-31.0)% (P lithium increased the baseline sodium clearance (CNa), but glomerular filtration rate and urine flow rate remained unchanged. 3. Dopamine increased CNa to similar values on the three study days. CLi increased to 40.9 (35.5-46.5) ml/min (endogenous lithium, P

The influence of diffusion and of reabsorption of radiation on the particle and energy balance of an infinitely long quasi-cylindrical discharge in hydrogen gas

International Nuclear Information System (INIS)

Goedheer, W.J.

1978-09-01

A numerical study of the pressure and temperature profiles of an infinitely long quasi-cylindrical discharge in hydrogen gas is presented. In particular the influence of the diffusion of atoms in the ground state and the reabsorption of Lyman-α and Lyman-β radiation on both the particle balance and the energy balance of the discharge is studied. Because the transport of the charged particles is corrected for toroidal effects in the regime of high collisionality which is present in the discharge, the model is quasi-cylindrical. The results obtained show an increase of the neutral density on the axis and of the ion and electron density near the wall of the discharge, as compared with earlier calculations in which both diffusion and reabsorption of radiation were neglected. The results are in agreement with measurements in the 'Ringboog' experiment. (Auth.)

Supra-Acetabular Brown Tumor due to Primary Hyperparathyroidism Associated with Chronic Renal Failure

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Rosaria M. Ruggeri

2010-01-01

Full Text Available A 63-year-old woman presented to the Orthopedic Unit of our hospital complaining of right hip pain of 6 months'duration associated with a worsening limp. Her past medical history included chronic renal insufficiency. Physical examination revealed deep pain in the iliac region and severe restriction of the right hip's articular function in the maximum degrees of range of motion. X-rays and CT scan detected an osteolytic and expansive lesion of the right supra-acetabular region with structural reabsorption of the right iliac wing. 99mTc-MDP whole-body bone scan showed an abnormal uptake in the right iliac region. Bone biopsy revealed an osteolytic lesion with multinucleated giant cells, indicating a brown tumor. Serum intact PTH was elevated (1020 pg/ml; normal values, 12 62 pg/ml, but her serum calcium was normal (total = 9.4 mg/dl, nv 8.5–10.5; ionized = 5.0 mg/dl, nv 4.2–5.4 due to the coexistence of chronic renal failure. 99mTc-MIBI scintigraphy revealed a single focus of sestamibi accumulation in the left retrosternal location, which turned out to be an intrathoracic parathyroid adenoma at surgical exploration. After surgical removal of the parathyroid adenoma, PTH levels decreased to 212 pg/ml. Three months after parathyroidectomy, the imaging studies showed complete recovery of the osteolytic lesion, thus avoiding any orthopedic surgery. This case is noteworthy because (1 primary hyperparathyroidism was not suspected due to the normocalcemia, likely attributable to the coexistence of chronic renal failure; and (2 it was associated with a brown tumor of unusual location (right supra-acetabular region.

The protective effects of tadalafil on renal damage following ischemia reperfusion injury in rats

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Bulent Erol

2015-09-01

Full Text Available Ischemia-reperfusion injury can cause renal damage, and phosphodiesterase inhibitors are reported to regulate antioxidant activity. We investigated the prevention of renal damage using tadalafil after renal ischemia reperfusion (I/R injury in rats. A total of 21 adult male Wistar albino rats were randomly divided into three groups of seven, including Group 1-control, Group 2-I/R, and Group 3-tadalafil + I/R group (I/R-T group received tadalafil intraperitoneally at 30 minutes before ischemia. Inducible nitric oxide synthase, endothelial nitric oxide synthase, malondialdehyde, and total antioxidant capacity levels were evaluated, and histopathological changes and apoptosis in the groups were examined. Tadalafil decreased malondialdehyde levels in the I/R group and increased the total antioxidant capacity level. Histopathological and immunohistochemical findings revealed that tadalafil decreased renal injury scores and the ratios of injured cells, as measured through apoptotic protease activating factor 1, inducible nitric oxide synthase, and endothelial nitric oxide synthase levels. We suggest that tadalafil has protective effects against I/R-related renal tissue injury.

Angiotensin II clamp prevents the second step in renal apical NHE3 internalization during acute hypertension

DEFF Research Database (Denmark)

Leong, Patrick K K; Yang, Li E; McDonough, Alicia A

2002-01-01

Acute hypertension inhibits proximal tubule (PT) sodium reabsorption. The resultant increase in NaCl delivery to the macula densa suppresses renin release. We tested whether the sustained pressure-induced inhibition of PT sodium reabsorption requires a renin-mediated decrease in ANG II levels. Pl...

Dietary supplementation with lish oil modifies renal reserve filtration capacity in postoperative, cyclosporin A-treated renal transplant recipients

NARCIS (Netherlands)

van der Heide, J. J. Homan; Bilo, H. J. G.; Donker, A. J. M.; Wilmink, J. M.; Sluiter, W. J.; Tegzess, Adam M.

The effect of a daily supplementation of 6 g fish oil (30% C20:5 omega-3 = EPA and 20% C22:6 omega-3 = DHA) for 1 month on renal function variables was investigated in a placebo-controlled (6 g coconut oil), prospective, randomized, double-blind study in acute postoperative cyclosporin A

Reduction of renal uptake of 111In-DOTA-labeled and A700-labeled RAFT-RGD during integrin αvβ3 targeting using single photon emission computed tomography and optical imaging.

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Briat, Arnaud; Wenk, Christiane H F; Ahmadi, Mitra; Claron, Michael; Boturyn, Didier; Josserand, Véronique; Dumy, Pascal; Fagret, Daniel; Coll, Jean-Luc; Ghezzi, Catherine; Sancey, Lucie; Vuillez, Jean-Philippe

2012-06-01

Integrin α(v)β(3) expression is upregulated during tumor growth and invasion in newly formed endothelial cells in tumor neovasculature and in some tumor cells. A tetrameric RGD-based peptide, regioselectively addressable functionalized template-(cyclo-[RGDfK])4 (RAFT-RGD), specifically targets integrin α(v)β(3) in vitro and in vivo. When labeled with indium-111, the RAFT-RGD is partially reabsorbed and trapped in the kidneys, limiting its use for further internal targeted radiotherapy and imaging investigations. We studied the effect of Gelofusine on RAFT-RGD renal retention in tumor-bearing mice. Mice were imaged using single photon emission computed tomography and optical imaging 1 and 24 h following tracer injection. Distribution of RAFT-RGD was further investigated by tissue removal and direct counting of the tracer. Kidney sections were analyzed by confocal microscopy. Gelofusine significantly induced a >50% reduction of the renal reabsorption of (111)In-DOTA-RAFT-RGD and A700-RAFT-RGD, without affecting tumor uptake. Injection of Gelofusine significantly reduced the renal retention of labeled RAFT-RGD, while increasing the tumor over healthy tissue ratio. These results will lead to the development of future therapeutic approaches. © 2012 Japanese Cancer Association.

Whites excrete a water load more rapidly than blacks.

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Weder, Alan B; Gleiberman, Lillian; Sachdeva, Amit

2009-04-01

A recent report demonstrated a racial difference in response to furosemide compatible with increased ion reabsorption in the thick ascending limb of the loop of Henle in blacks. Urinary dilution is another function of the loop-diuretic-sensitive Na,K,2Cl cotransporter in the thick ascending limb, and racial differences in urinary diluting capacity have not been reported previously. We assessed diluting segment (cortical thick ascending limb and distal convoluted tubule) function in black and white normotensives in 2 studies using a water-loading approach. In both studies, we found that whites excreted a water load more rapidly than blacks. In the first study, the final free water clearance rates (mean+/-SD) were 7.3+/-4.7 mL/min in whites (n=17, 7 females and 10 males) and 3.8+/-3.6 mL/min in blacks (n=14, 9 females and 5 males; Pwater clearance rates were 8.3+/-2.6 mL/min in whites (n=17, 8 females and 9 males) and 6.4+/-1.8 mL/min in blacks (n=11, 8 females and 3 males; Pwater excretion. We conclude that our observations are most consistent with a lower capacity of ion reabsorption in the renal diluting segment in blacks. Slower excretion of an acute water load may have been an advantage during natural selection of humans living in arid, hot climates.

Homer W. Smith's contribution to renal physiology.

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Giebisch, Gerhard

2004-01-01

Homer Smith was, for three decades, from the 1930s until his death in 1962, one of the leaders in the field of renal physiology. His contributions were many: he played a major role in introducing and popularizing renal clearance methods, introduced non-invasive methods for the measurement of glomerular filtration rate, of renal blood flow and tubular transport capacity, and provided novel insights into the mechanisms of excretion of water and electrolytes. Homer Smith's contributions went far beyond his personal investigations. He was a superb writer of several inspiring textbooks of renal physiology that exerted great and lasting influence on the development of renal physiology. Smith's intellectual insights and ability for critical analysis of data allowed him to create broad concepts that defined the functional properties of glomeruli, tubules and the renal circulation. A distinguishing feature of Homer Smith's career was his close contact and collaboration, over many years, with several clinicians of his alma mater, New York University. For initiating these pathophysiological investigations, he is justly credited to have advanced, in a major way, our understanding of altered renal function in disease. Smith's lasting scientific impact is also reflected by a whole school of investigators that trained with him and who applied his methods, analyses and concepts to the study of renal function all over the world. So great was his influence and preeminence that Robert Pitts, in his excellent tribute to Homer Smith in the Memoirs of the National Academy of Science states that his death brought an end to what might be aptly called the Smithian Era of renal physiology.

Alterações renais nas doenças falciformes Renal abnormalities in sickle cell disease

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Isis Q. Magalhães

2007-09-01

abnormalities, hemodynamic changes and renal hormone synthesis alterations (erythropoietin, renin, prostaglandins. These changes appear in childhood with consequences including chronic anemia, increased blood flow and vaso-occlusion, especially within the renal medulla. In SS disease, the glomerular filtration rate (GFR is markedly higher in young patients but this drops with age. As a consequence of abnormalities in the distal nephron function there is reduced capacity of urine acidification, potassium excretion and hyposthenuria. Among the clinical effects of the latter are polyuria, nocturia, enuresis and a susceptability for dehydration. Abnormalities of the proximal tubular function include increased reabsorption of phosphates and b2 microglobulin and incresed secretion of uric acid and creatinine. For this reason, creatinine clearance significantly overestimates the glomerular filtration rate making creatinine learance inappropriate to detect early renal function impairment. Proteinuria occurs in 29-50% of over 10-years-old SS patients with 2/3 progressing to chronic renal failure. The use of angiotensin-converting enzyme inhibitor proves to be successful to reduce proteinuria which may have an impact of the progression of renal failure. Microalbuminuria is a sensitive marker of sickle nephropathy that precedes proteinuria. In pediatric population a prevalence of 19% of microbuminuria was observed; a percentage that increases with age and has a positive association with lower hemoglobin levels, higher leucocyte counts and acute chest syndrome. Screening for microalbuminuria is recommended from the age of 10 years old. A multicentric trial is ongoing with the aim of demonstrate potential benefits of early hydroxyurea therapy in the prevention of chronic organic lesions. (BabyHUG.

Consideration on the diagnostic ability of various imaging techniques in relation to renal tumor

International Nuclear Information System (INIS)

Ike, Katsushi

1984-01-01

Radiological diagnosis of renal tumors is being improved with the increased imaging accuracy which has resulted from advancement in the various equipment used and improvement in techniques. However, at the clinical level, diagnostic procedures based on the characteristics of the delineated images are not yet established and the diverse diagnostic procedures are being conducted currently in a stereotyped manner. In this study, the images of 61 cases diagnosed as renal tumor were analysed retrospectively with the purpose of establishing the imaging accuracy, capacity for diagnosis based on image characteristics and a subseguent proper diagnostic procedure. It was found that CT and Angio gave similar diagnostic accuracy. It was further revealed that US images enabled to differentiate renal tumors from the more commonly experienced renal cystic disease. For determination of tunica involucrum infiltration, which is essential to diagnose Stage I and II renal tumors, CT was proved to be superior to Angio. CT and US were also to be so in the determination of metastasis to para-aortic lymph nodes which is a Stage III criterion. In recent years, CT and US imaging accuracies have increased, hence the improvement in the capacity to diagnose non-observable renal tumors is highly expected. (author)

Comorbid renal tubular damage and hypoalbuminemia exacerbate cardiac prognosis in patients with chronic heart failure.

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Otaki, Yoichiro; Watanabe, Tetsu; Takahashi, Hiroki; Funayama, Akira; Kinoshita, Daisuke; Yokoyama, Miyuki; Takahashi, Tetsuya; Nishiyama, Satoshi; Arimoto, Takanori; Shishido, Tetsuro; Miyamoto, Takuya; Konta, Tsuneo; Kubota, Isao

2016-02-01

Renal tubular damage (RTD) and hypoalbuminemia are risks for poor prognosis in patients with chronic heart failure (CHF). Renal tubules play a pivotal role in amino acid and albumin reabsorption, which maintain serum albumin levels. The aims of the present study were to (1) examine the association of RTD with hypoalbuminemia, and (2) assess the prognostic importance of comorbid RTD and hypoalbuminemia in patients with CHF. We measured N-acetyl-β-D-glucosamidase (NAG) levels and the urinary β2-microglobulin to creatinine ratio (UBCR) in 456 patients with CHF. RTD was defined as UBCR ≥ 300 μg/g or NAG ≥ 14.2 U/g. There were moderate correlations between RTD markers and serum albumin (NAG, r = -0.428, P < 0.0001; UBCR, r = -0.399, P < 0.0001). Multivariate logistic analysis showed that RTD was significantly related to hypoalbuminemia in patients with CHF. There were 134 cardiac events during a median period of 808 days. The comorbidity of RTD and hypoalbuminemia was increased with advancing New York Heart Association functional class. Multivariate Cox proportional hazard regression analysis showed that the presence of RTD and hypoalbuminemia was associated with cardiac events. The net reclassification index was significantly improved by adding RTD and hypoalbuminemia to the basic risk factors. Comorbid RTD and hypoalbuminemia are frequently observed and increase the risk for extremely poor outcome in patients with CHF.

Cystinuria in a maned wolf.

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Bush, M; Bovee, K C

1978-11-01

A renal calculus composed principally of the amino acid, cystine, was found in an 8-year-old male maned wolf (Chrysocyon brachyurus). Cystine crystals were found in the urine sediment. The renal clearance of 10 amino acids was abnormal, whereas reabsorption of others was normal. The renal clearance of cystine, lysine, ornithine, and arginine exceeded the filtered load. The renal tubular handling of glucose, phosphate, sodium, potassium, and uric acid was identical to that for the clinically normal dog. These findings indicated an isolated renal tubular defect for cystine and other amino acids.

Redesign of negatively charged 111In-DTPA-octreotide derivative to reduce renal radioactivity.

Science.gov (United States)

Oshima, Nobuhiro; Akizawa, Hiromichi; Kawashima, Hidekazu; Zhao, Songji; Zhao, Yan; Nishijima, Ken-Ichi; Kitamura, Yoji; Arano, Yasushi; Kuge, Yuji; Ohkura, Kazue

2017-05-01

Radiolabeled octreotide derivatives have been studied as diagnostic and therapeutic agents for somatostatin receptor-positive tumors. To prevent unnecessary radiation exposure during their clinical application, the present study aimed to develop radiolabeled peptides which could reduce radioactivity levels in the kidney at both early and late post-injection time points by introducing a negative charge with an acidic amino acid such as L-aspartic acid (Asp) at a suitable position in 111 In-DTPA-conjugated octreotide derivatives. Biodistribution of the radioactivity was evaluated in normal mice after administration of a novel radiolabeled peptide by a counting method. The radiolabeled species remaining in the kidney were identified by comparing their HPLC data with those obtained by alternative synthesis. The designed and synthesized radiolabeled peptide 111 In-DTPA-d-Phe -1 -Asp 0 -d-Phe 1 -octreotide exhibited significantly lower renal radioactivity levels than those of the known 111 In-DTPA-d-Phe 1 -octreotide at 3 and 24h post-injection. The radiolabeled species in the kidney at 24h after the injection of new octreotide derivative represented 111 In-DTPA-d-Phe-OH and 111 In-DTPA-d-Phe-Asp-OH as the metabolites. Their radiometabolites and intact 111 In-DTPA-conjugated octreotide derivative were observed in urine within 24h post-injection. The present study provided a new example of an 111 In-DTPA-conjugated octreotide derivative having the characteristics of both reduced renal uptake and shortened residence time of radioactivity in the kidney. It is considered that this kinetic control was achieved by introducing a negative charge on the octreotide derivative thereby suppressing the reabsorption in the renal tubules and affording the radiometabolites with appropriate lipophilicity. Copyright © 2017 Elsevier Inc. All rights reserved.

Redesign of negatively charged 111In-DTPA-octreotide derivative to reduce renal radioactivity

International Nuclear Information System (INIS)

Oshima, Nobuhiro; Akizawa, Hiromichi; Kawashima, Hidekazu; Zhao, Songji; Zhao, Yan; Nishijima, Ken-ichi; Kitamura, Yoji; Arano, Yasushi; Kuge, Yuji; Ohkura, Kazue

2017-01-01

Introduction: Radiolabeled octreotide derivatives have been studied as diagnostic and therapeutic agents for somatostatin receptor-positive tumors. To prevent unnecessary radiation exposure during their clinical application, the present study aimed to develop radiolabeled peptides which could reduce radioactivity levels in the kidney at both early and late post-injection time points by introducing a negative charge with an acidic amino acid such as L-aspartic acid (Asp) at a suitable position in 111 In-DTPA-conjugated octreotide derivatives. Methods: Biodistribution of the radioactivity was evaluated in normal mice after administration of a novel radiolabeled peptide by a counting method. The radiolabeled species remaining in the kidney were identified by comparing their HPLC data with those obtained by alternative synthesis. Results: The designed and synthesized radiolabeled peptide 111 In-DTPA-D-Phe −1 -Asp 0 -D-Phe 1 -octreotide exhibited significantly lower renal radioactivity levels than those of the known 111 In-DTPA-D-Phe 1 -octreotide at 3 and 24 h post-injection. The radiolabeled species in the kidney at 24 h after the injection of new octreotide derivative represented 111 In-DTPA-D-Phe-OH and 111 In-DTPA-D-Phe-Asp-OH as the metabolites. Their radiometabolites and intact 111 In-DTPA-conjugated octreotide derivative were observed in urine within 24 h post-injection. Conclusion: The present study provided a new example of an 111 In-DTPA-conjugated octreotide derivative having the characteristics of both reduced renal uptake and shortened residence time of radioactivity in the kidney. It is considered that this kinetic control was achieved by introducing a negative charge on the octreotide derivative thereby suppressing the reabsorption in the renal tubules and affording the radiometabolites with appropriate lipophilicity.

SGLT2 inhibitors: molecular design and potential differences in effect.

Science.gov (United States)

Isaji, Masayuki

2011-03-01

The physiological and pathological handling of glucose via sodium-glucose cotransporter-2 (SGLT2) in the kidneys has been evolving, and SGLT2 inhibitors have been focused upon as a novel drug for treating diabetes. SGLT2 inhibitors enhance renal glucose excretion by inhibiting renal glucose reabsorption. Consequently, SGLT2 inhibitors reduce plasma glucose insulin independently and improve insulin resistance in diabetes. To date, various SGLT2 inhibitors have been developed and evaluated in clinical studies. The potency and positioning of SGLT2 inhibitors as an antidiabetic drug are dependent on their characteristic profile, which induces selectivity, efficacy, pharmacokinetics, and safety. This profile decides which SGLT2 inhibitors can be expected for application of the theoretical concept of reducing renal glucose reabsorption for the treatment of diabetes. I review the structure and advancing profile of various SGLT2 inhibitors, comparing their similarities and differences, and discuss the expected SGLT2 inhibitors for an emerging category of antidiabetic drugs.

Functional and clinical evaluation of renal injury in patients treated with adjuvant chemoradiotherapy for gastric cancer: Low dose and comorbidity considerations

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Roman Ibrahimov

2016-01-01

Conclusion: Functional renal impairment without any clinical signs or symptoms can be observed in low doses after radiotherapy. Careful treatment planning and a detailed evaluation of the functional renal capacity before treatment may help to reduce late renal toxicity.

Activation of thiazide-sensitive co-transport by angiotensin II in the cyp1a1-Ren2 hypertensive rat.

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Ali Ashek

Full Text Available Transgenic rats with inducible expression of the mouse Ren2 gene were used to elucidate mechanisms leading to the development of hypertension and renal injury. Ren2 transgene activation was induced by administration of a naturally occurring aryl hydrocarbon, indole-3-carbinol (100 mg/kg/day by gastric gavage. Blood pressure and renal parameters were recorded in both conscious and anesthetized (butabarbital sodium; 120 mg/kg IP rats at selected time-points during the development of hypertension. Hypertension was evident by the second day of treatment, being preceded by reduced renal sodium excretion due to activation of the thiazide-sensitive sodium-chloride co-transporter. Renal injury was evident after the first day of transgene induction, being initially limited to the pre-glomerular vasculature. Mircoalbuminuria and tubuloinsterstitial injury developed once hypertension was established. Chronic treatment with either hydrochlorothiazide or an AT1 receptor antagonist normalized sodium reabsorption, significantly blunted hypertension and prevented renal injury. Urinary aldosterone excretion was increased ≈ 20 fold, but chronic mineralocorticoid receptor antagonism with spironolactone neither restored natriuretic capacity nor prevented hypertension. Spironolactone nevertheless ameliorated vascular damage and prevented albuminuria. This study finds activation of sodium-chloride co-transport to be a key mechanism in angiotensin II-dependent hypertension. Furthermore, renal vascular injury in this setting reflects both barotrauma and pressure-independent pathways associated with direct detrimental effects of angiotensin II and aldosterone.

Renal capsule for augmentation cystoplasty in canine model: a favorable biomaterial?

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Mehdi Salehipour

2016-04-01

Full Text Available ABSTRACT Purpose: To evaluate effectiveness of canine renal capsule for augmentation cystoplasty. Materials and Methods: Ten adult dogs participated in this study. After induction of anesthesia each animal underwent bed side urodynamic study, bladder capacity and bladder pressure was recorded. Then via mid line incision abdominal cavity was entered, right kidney was identified and its capsule was dissected. Bladder augmentation was done by anastomosing the renal capsule to the bladder. After 6 months bed side urodynamic study was performed again and changes in bladder volume and pressure were recorded. Then the animals were sacrificed and the augmented bladders were sent for histopathology evaluation. Results: Mean maximum anatomic bladder capacity before cystoplasty was 334.00±11.40cc which increased to 488.00±14.83cc post-operatively (p=0.039. Mean anatomic bladder pressure before cystoplasty was 19.00±1.58cmH2O which decreased to 12.60±1.14cmH2O post-operatively (p=0.039. Histopathology evaluation revealed epithelialization of the renal capsule with urothelium without evidence of fibrosis, collagen deposits or contracture. Conclusions: Our data shows that renal capsule is a favorable biomaterial for bladder augmentation in a canine model.

The influence of percutaneous nephrolithotomy on human systemic stress response, SIRS and renal function.

Science.gov (United States)

Shen, Pengfei; Wei, Wuran; Yang, Xiaochun; Zeng, Hao; Li, Xiong; Yang, Jie; Wang, Jia; Huang, Jiaoti

2010-10-01

The objective of this study is to investigate the influences of percutaneous nephrolithotomy (PNL) and open surgery nephrolithotomy on the systemic stress response, SIRS and renal function. Forty patients with kidney calculi were enrolled in the study. Twenty cases were randomized to the PNL group and the other twenty cases to the open surgery group. Levels of C-reactive protein (CRP), interleukin-6(IL-6), β(2)-microglobulin (β(2)-MG), respiration rate, heart rate, body temperature and white blood cell counts were examined. CRP and IL-6 were measured in all patients pre-operatively and on post-operative days 1, 3 and 6, respectively. There was significant difference in their pre- and post-operation levels (P PNL group and 12 cases in open surgery group; there was significant difference between the two groups (P 0.05). Urine β(2)-MG levels were also measured. There was significant difference between pre- and the first day post-PNL (P PNL (P > 0.05). There was significant difference between pre- and first and third day post-open surgery (P 0.05). There was significant difference between two groups at the first, third and sixth days (P PNL group and open surgery group to some extent. The degree of stress response of PNL is lower than that of open surgery, proving the advantages of PNL with reference to serum immunology. There were cases in both the groups with SIRS, but the degree of SIRS in PNL group was lesser than the other group. Both the groups have no obvious effect on glomerular filtration function after operation and have effect on renal tubular reabsorption in the early stage after operation; but the recovery of the PNL group is faster than the open surgery group. It is thus shown that PNL is much safer and more feasible and has lesser effect on renal function.

How Kidney Cell Death Induces Renal Necroinflammation.

Science.gov (United States)

Mulay, Shrikant R; Kumar, Santhosh V; Lech, Maciej; Desai, Jyaysi; Anders, Hans-Joachim

2016-05-01

The nephrons of the kidney are independent functional units harboring cells of a low turnover during homeostasis. As such, physiological renal cell death is a rather rare event and dead cells are flushed away rapidly with the urinary flow. Renal cell necrosis occurs in acute kidney injuries such as thrombotic microangiopathies, necrotizing glomerulonephritis, or tubular necrosis. All of these are associated with intense intrarenal inflammation, which contributes to further renal cell loss, an autoamplifying process referred to as necroinflammation. But how does renal cell necrosis trigger inflammation? Here, we discuss the role of danger-associated molecular patterns (DAMPs), mitochondrial (mito)-DAMPs, and alarmins, as well as their respective pattern recognition receptors. The capacity of DAMPs and alarmins to trigger cytokine and chemokine release initiates the recruitment of leukocytes into the kidney that further amplify necroinflammation. Infiltrating neutrophils often undergo neutrophil extracellular trap formation associated with neutrophil death or necroptosis, which implies a release of histones, which act not only as DAMPs but also elicit direct cytotoxic effects on renal cells, namely endothelial cells. Proinflammatory macrophages and eventually cytotoxic T cells further drive kidney cell death and inflammation. Dissecting the molecular mechanisms of necroinflammation may help to identify the best therapeutic targets to limit nephron loss in kidney injury. Copyright © 2016 Elsevier Inc. All rights reserved.

Associations between plasma tenofovir concentration and renal function markers in HIV-infected women

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Mwila Mulubwa

2016-07-01

Objective: To investigate the correlation between plasma tenofovir (TFV concentration and certain renal function markers in HIV-infected women on TDF antiretroviral therapy (ART.These markers were also compared to a HIV-uninfected control group. Methods: HIV-infected women (n = 30 on TDF-based ART were matched with 30 controls forage and body mass index. Renal markers analysed were estimated glomerular filtration rate (eGFR, creatinine clearance (CrCl, serum creatinine, albuminuria, glucosuria, serum urea, serum uric acid, urine sodium and maximum tubular reabsorption of phosphate. Baseline eGFR and CrCl data were obtained retrospectively for the HIV-infected women. Plasma TFV was assayed using a validated HPLC-MS/MS method. Step wise regression, Mann–Whitney test, unpaired and paired t-tests were applied in the statistical analyses. Results: TFV concentration was independently associated with albuminuria (adjusted r2 = 0.339; p = 0.001 in HIV-infected women. In the adjusted (weight analysis, eGFR (p = 0.038,CrCl (p = 0.032 and albuminuria (p = 0.048 were significantly higher in HIV-infected compared to the uninfected women, but eGFR was abnormally high in HIV-infected women. Both eGFR (p < 0.001 and CrCl (p = 0.008 increased from baseline to follow-up in HIV-infected women. Conclusion: Plasma TFV concentration was associated with increased albuminuria in HIV infected women in this sub-study. Both eGFR and CrCl were increased in HIV-infected women from baseline. These findings should be confirmed in larger studies, and hyperfiltration in HIV-infected women warrants further investigation.

Kidney protection during peptide receptor radionuclide therapy with somatostatin analogues.

NARCIS (Netherlands)

Rolleman, E.J.; Melis, M.; Valkema, R.; Boerman, O.C.; Krenning, E.P.; Jong, M. de

2010-01-01

This review focuses on the present status of kidney protection during peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues. This treatment modality for somatostatin receptor-positive tumours is limited by renal reabsorption and retention of radiolabelled peptides

sup(99m)Tc-DMSA renal scintigraphy in renal failure due to various renal diseases

Energy Technology Data Exchange (ETDEWEB)

Hosokawa, S; Daijo, K; Okabe, T; Kawamura, J; Hara, A [Kyoto Univ. (Japan). Hospital

1979-08-01

Renal contours in renal failure were studied by means of sup(99m)Tc-dimercaptosuccinic acid (DMSA) renoscintigraphy. Renal cortical images were obtained even in renal failure cases. Causes of renal failure were chronic glomerulonephritis in 7, bilateral renal tuberculosis in 2, chronic pyelonephritis in 3, bilateral renal calculi in 3, diabetic nephropathy in 2, polycystic kidney disease in 2 and stomach cancer in 1.

sup(99m)Tc-DMSA renal scintigraphy in renal failure due to various renal diseases

International Nuclear Information System (INIS)

Hosokawa, Shin-ichi; Daijo, Kazuyuki; Okabe, Tatsushiro; Kawamura, Juichi; Hara, Akira

1979-01-01

Renal contours in renal failure were studied by means of sup(99m)Tc-dimercaptosuccinic acid (DMSA) renoscintigraphy. Renal cortical images were obtained even in renal failure cases. Causes of renal failure were chronic glomerulonephritis in 7, bilateral renal tuberculosis in 2, chronic pyelonephritis in 3, bilateral renal calculi in 3, diabetic nephropathy in 2, polycystic kidney disease in 2 and stomach cancer in 1. (author)

Sensitivity of fibroblast growth factor 23 measurements in tumor-induced osteomalacia.

NARCIS (Netherlands)

Imel, E.A.; Peacock, M.; Pitukcheewanont, P.; Heller, H.J.; Ward, LM; Shulman, D.; Kassem, M.; Rackoff, P.; Zimering, M.; Dalkin, A.; Drobny, E.; Colussi, G.; Shaker, J.L.; Hoogendoorn, E.H.; Hui, S.L.; Econs, M.J.

2006-01-01

CONTEXT: Tumor-induced osteomalacia (TIO) is a paraneoplastic syndrome of hypophosphatemia, decreased renal phosphate reabsorption, normal or low serum 1,25-dihydryxyvitamin-D concentration, myopathy, and osteomalacia. Fibroblast growth factor 23 (FGF23) is a phosphaturic protein overexpressed in

Renal computed angiography. Part I: Renal CT phlebography. Renal veins variants

International Nuclear Information System (INIS)

Al-Amin, M.; Krupev, M.; Hadjidekov, V.; Plachkov, I.

2012-01-01

The changing trend in renal surgery, transplantation and minimal invasive urology implies preprocedure evaluation of renal veins. Development of imaging methods offers new possibilities for venographic visualization. The goal of this study is to present authors experience in visualization of renal veins using 64 MDCT and to evaluate the utility in assessments of their variants. 128 patients (68 females and 60 males, mean age 53,3) with urological complaints underwent 64MDCT examination including CT angiography. Contrast enhancement includes 3-4ml/sec injection flow of 90 ml contrast medium followed by 20 ml saline at the same rate. In 23 out of 128 examined patients some of the common variants of the renal vein is found. 64 MDCT angiography visualize very well renal veins and becomes method of choice in preoperative assessment of renal vein anatomy. (authors)

Analysis of the efficacy of SGLT2 inhibitors using semi-mechanistic model

Science.gov (United States)

Demin, Oleg; Yakovleva, Tatiana; Kolobkov, Dmitry; Demin, Oleg

2014-01-01

The Renal sodium-dependent glucose co-transporter 2 (SGLT2) is one of the most promising targets for the treatment of type 2 diabetes. Two SGLT2 inhibitors, dapagliflozin, and canagliflozin, have already been approved for use in USA and Europe; several additional compounds are also being developed for this purpose. Based on the in vitro IC50 values and plasma concentration of dapagliflozin measured in clinical trials, the marketed dosage of the drug was expected to almost completely inhibit SGLT2 function and reduce glucose reabsorption by 90%. However, the administration of dapagliflozin resulted in only 30–50% inhibition of reabsorption. This study was aimed at investigating the mechanism underlying the discrepancy between the expected and observed levels of glucose reabsorption. To this end, systems pharmacology models were developed to analyze the time profile of dapagliflozin, canagliflozin, ipragliflozin, empagliflozin, and tofogliflozin in the plasma and urine; their filtration and active secretion from the blood to the renal proximal tubules; reverse reabsorption; urinary excretion; and their inhibitory effect on SGLT2. The model shows that concentration levels of tofogliflozin, ipragliflozin, and empagliflozin are higher than levels of other inhibitors following administration of marketed SGLT2 inhibitors at labeled doses and non-marketed SGLT2 inhibitors at maximal doses (approved for phase 2/3 studies). All the compounds exhibited almost 100% inhibition of SGLT2. Based on the results of our model, two explanations for the observed low efficacy of SGLT2 inhibitors were supported: (1) the site of action of SGLT2 inhibitors is not in the lumen of the kidney's proximal tubules, but elsewhere (e.g., the kidneys proximal tubule cells); and (2) there are other transporters that could facilitate glucose reabsorption under the conditions of SGLT2 inhibition (e.g., other transporters of SGLT family). PMID:25352807

Analysis of efficacy of SGLT2 inhibitors using semi-mechanistic model

Directory of Open Access Journals (Sweden)

Oleg eDemin Jr

2014-10-01

Full Text Available Renal sodium-dependent glucose co-transporter 2 (SGLT2 is one of the most promising targets for the treatment of type 2 diabetes. Two SGLT2 inhibitors, dapagliflozin and canagliflozin, have already been approved for use in USA and Europe; several additional compounds are also being developed for this purpose. Based on the in vitro IC50 values and plasma concentration of dapagliflozin measured in clinical trials, the marketed dosage of the drug was expected to almost completely inhibit SGLT2 function and reduce glucose reabsorption by 90%. However, the administration of dapagliflozin resulted in only 30–50% inhibition of reabsorption. This study was aimed at investigating the mechanism underlying the discrepancy between the expected and observed levels of glucose reabsorption. To this end, systems pharmacology models were developed to analyze the time profile of dapagliflozin, canagliflozin, ipragliflozin, empagliflozin, and tofogliflozin in the plasma and urine; their filtration and active secretion from the blood to the renal proximal tubules; reverse reabsorption; urinary excretion; and their inhibitory effect on SGLT2. The model shows that concentration levels of tofogliflozin, ipragliflozin, and empagliflozin are higher than levels of other inhibitors following administration of marketed SGLT2 inhibitors at labeled doses and non-marketed SGLT2 inhibitors at maximal doses (approved for phase 2/3 studies. All the compounds exhibited almost 100% inhibition of SGLT2. Based on the results of our model, two explanations for the observed low efficacy of SGLT2 inhibitors were supported: 1 the site of action of SGLT2 inhibitors is not in the lumen of the kidney’s proximal tubules, but elsewhere (e.g., the kidneys proximal tubule cells; and 2 there are other transporters that could facilitate glucose reabsorption under the conditions of SGLT2 inhibition (e.g., other transporters of SGLT family.

Sensitivity of fibroblast growth factor 23 measurements in tumor-induced osteomalacia

DEFF Research Database (Denmark)

Imel, Erik A; Peacock, Munro; Pitukcheewanont, Pisit

2006-01-01

Tumor-induced osteomalacia (TIO) is a paraneoplastic syndrome of hypophosphatemia, decreased renal phosphate reabsorption, normal or low serum 1,25-dihydryxyvitamin-D concentration, myopathy, and osteomalacia. Fibroblast growth factor 23 (FGF23) is a phosphaturic protein overexpressed in tumors t...

Characterization of Organic Anion Transporter 2 (SLC22A7): A Highly Efficient Transporter for Creatinine and Species-Dependent Renal Tubular Expression.

Science.gov (United States)

Shen, Hong; Liu, Tongtong; Morse, Bridget L; Zhao, Yue; Zhang, Yueping; Qiu, Xi; Chen, Cliff; Lewin, Anne C; Wang, Xi-Tao; Liu, Guowen; Christopher, Lisa J; Marathe, Punit; Lai, Yurong

2015-07-01

The contribution of organic anion transporter OAT2 (SLC22A7) to the renal tubular secretion of creatinine and its exact localization in the kidney are reportedly controversial. In the present investigation, the transport of creatinine was assessed in human embryonic kidney (HEK) cells that stably expressed human OAT2 (OAT2-HEK) and isolated human renal proximal tubule cells (HRPTCs). The tubular localization of OAT2 in human, monkey, and rat kidney was characterized. The overexpression of OAT2 significantly enhanced the uptake of creatinine in OAT2-HEK cells. Under physiologic conditions (creatinine concentrations of 41.2 and 123.5 µM), the initial rate of OAT2-mediated creatinine transport was approximately 11-, 80-, and 80-fold higher than OCT2, multidrug and toxin extrusion protein (MATE)1, and MATE2K, respectively, resulting in approximately 37-, 1850-, and 80-fold increase of the intrinsic transport clearance when normalized to the transporter protein concentrations. Creatinine intracellular uptake and transcellular transport in HRPTCs were decreased in the presence of 50 µM bromosulfophthalein and 100 µM indomethacin, which inhibited OAT2 more potently than other known creatinine transporters, OCT2 and multidrug and toxin extrusion proteins MATE1 and MATE2K (IC50: 1.3 µM vs. > 100 µM and 2.1 µM vs. > 200 µM for bromosulfophthalein and indomethacin, respectively) Immunohistochemistry analysis showed that OAT2 protein was localized to both basolateral and apical membranes of human and cynomolgus monkey renal proximal tubules, but appeared only on the apical membrane of rat proximal tubules. Collectively, the findings revealed the important role of OAT2 in renal secretion and possible reabsorption of creatinine and suggested a molecular basis for potential species difference in the transporter handling of creatinine. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

Reversed polarized delivery of an aquaporin-2 mutant causes dominant nephrogenic diabetes insipidus.

NARCIS (Netherlands)

Kamsteeg, E.J.; Bichet, D.G.; Konings, I.B.M.; Nivet, H.; Lonergan, M.; Arthus, M.F.; Os, C.H. van; Deen, P.M.T.

2003-01-01

Vasopressin regulates body water conservation by redistributing aquaporin-2 (AQP2) water channels from intracellular vesicles to the apical surface of renal collecting ducts, resulting in water reabsorption from urine. Mutations in AQP2 cause autosomal nephrogenic diabetes insipidus (NDI), a disease

Continuous renal replacement therapy improves renal recovery from acute renal failure.

Science.gov (United States)

Jacka, Michael J; Ivancinova, Xenia; Gibney, R T Noel

2005-03-01

Acute renal failure (ARF) occurs in up to 10% of critically ill patients, with significant associated morbidity and mortality. The optimal mode of renal replacement therapy (RRT) remains controversial. This retrospective study compared continuous renal replacement therapy (CRRT) and intermittent hemodialysis (IHD) for RRT in terms of intensive care unit (ICU) and hospital mortality, and renal recovery. We reviewed the records of all patients undergoing RRT for the treatment of ARF over a 12-month period. Patients were compared according to mode of RRT, demographics, physiologic characteristics, and outcomes of ICU and hospital mortality and renal recovery using the Chi square, Student's t test, and multiple logistic regression as appropriate. 116 patients with renal insufficiency underwent RRT during the study period. Of these, 93 had ARF. The severity of illness of CRRT patients was similar to that of IHD patients using APACHE II (25.1 vs 23.5, P = 0.37), but they required significantly more intensive nursing (therapeutic intervention scale 47.8 vs 37.6, P = 0.0001). Mortality was associated with lower pH at presentation (P = 0.003) and increasing age (P = 0.03). Renal recovery was significantly more frequent among patients initially treated with CRRT (21/24 vs 5/14, P = 0.0003). Further investigation to define optimal timing, dose, and duration of RRT may be beneficial. Although further study is needed, this study suggests that renal recovery may be better after CRRT than IHD for ARF. Mortality was not affected significantly by RRT mode.

Gastrointestinal and renal responses to variable water intake in whitebellied sunbirds and New Holland honeyeaters.

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Purchase, Cromwell; Napier, Kathryn R; Nicolson, Susan W; McWhorter, Todd J; Fleming, Patricia A

2013-05-01

Nectarivores face a constant challenge in terms of water balance, experiencing water loading or dehydration when switching between food plants or between feeding and fasting. To understand how whitebellied sunbirds and New Holland honeyeaters meet the challenges of varying preformed water load, we used the elimination of intramuscular-injected [(14)C]-l-glucose and (3)H2O to quantify intestinal and renal water handling on diets varying in sugar concentration. Both sunbirds and honeyeaters showed significant modulation of intestinal water absorption, allowing excess water to be shunted through the intestine when on dilute diets. Despite reducing their fractional water absorption, both species showed linear increases in water flux and fractional body water turnover as water intake increased (both afternoon and morning), suggesting that the modulation of fractional water absorption was not sufficient to completely offset dietary water loads. In both species, glomerular filtration rate was independent of water gain (but was higher for the afternoon), as was renal fractional water reabsorption (measured in the afternoon). During the natural overnight fast, both sunbirds and honeyeaters arrested whole kidney function. Evaporative water loss in sunbirds was variable but correlated with water gain. Both sunbirds and honeyeaters appear to modulate intestinal water absorption as an important component of water regulation to help deal with massive preformed water loads. Shutting down glomerular filtration rate during the overnight fast is another way of saving energy for osmoregulatory function. Birds maintain osmotic balance on diets varying markedly in preformed water load by varying both intestinal water absorption and excretion through the intestine and kidneys.

Renal plasticity in response to feeding in the Burmese python, Python molurus bivittatus.

Science.gov (United States)

Esbaugh, A J; Secor, S M; Grosell, M

2015-10-01

Burmese pythons are sit-and-wait predators that are well adapted to go long periods without food, yet subsequently consume and digest single meals that can exceed their body weight. These large feeding events result in a dramatic alkaline tide that is compensated by a hypoventilatory response that normalizes plasma pH; however, little is known regarding how plasma HCO3(-) is lowered in the days post-feeding. The current study demonstrated that Burmese pythons contain the cellular machinery for renal acid-base compensation and actively remodel the kidney to limit HCO3(-) reabsorption in the post-feeding period. After being fed a 25% body weight meal plasma total CO2 was elevated by 1.5-fold after 1 day, but returned to control concentrations by 4 days post-feeding (d pf). Gene expression analysis was used to verify the presence of carbonic anhydrase (CA) II, IV and XIII, Na(+) H(+) exchanger 3 (NHE3), the Na(+) HCO3(-) co-transporter (NBC) and V-type ATPase. CA IV expression was significantly down-regulated at 3 dpf versus fasted controls. This was supported by activity analysis that showed a significant decrease in the amount of GPI-linked CA activity in isolated kidney membranes at 3 dpf versus fasted controls. In addition, V-type ATPase activity was significantly up-regulated at 3 dpf; no change in gene expression was observed. Both CA II and NHE3 expression was up-regulated at 3 dpf, which may be related to post-prandial ion balance. These results suggest that Burmese pythons actively remodel their kidney after feeding, which would in part benefit renal HCO3(-) clearance. Copyright © 2015 Elsevier Inc. All rights reserved.

Empagliflozin in the treatment of type 2 diabetes: evidence to date

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Shubrook JH

2015-10-01

Full Text Available Jay H Shubrook,1 Babak Baradar Bokaie,2 Sarah E Adkins31Primary Care Department, Clinical Research and Diabetes Services, Touro University College of Osteopathic Medicine, Vallejo, CA, USA; 2The Diabetes Institute at Ohio University, Ohio University, Athens, OH, USA; 3Pharmacy Practice and Administration, College of Pharmacy, Ohio State University, Athens, OH, USA Abstract: In the last decade, researchers have gained a greater understanding of the pathophysiologic mechanisms of type 2 diabetes as a chronic and progressive disease. One of the more recent treatment targets is the kidney. The kidneys become maladaptive in diabetes by increasing the reabsorption of glucose above the normal physiologic renal threshold. This discovery has led to the development of the sodium/glucose cotransporter 2 inhibitors (SGLT2. These agents readjust the renal threshold for glucose reabsorption to a lower level and decrease glucose reabsorption, while increasing urinary glucose when the glucose is above the renal threshold and subsequently lowering plasma glucose. The mechanism of action of the SGLT2 inhibitors is insulin independent, which makes them a novel treatment of diabetes. At the time of preparation of this manuscript, there were three SGLT2 inhibitors available in the US. This manuscript focuses on empagliflozin, the newest SGLT2 inhibitor, the trials in its development, and the clinical data available to date. Further, the authors propose future applications of empagliflozin, including in the treatment of type 1 diabetes, and its potential role in renoprotection. Keywords: SGLT-2 inhibitors, empagliflozin, type 2 diabetes, kidneys, type 1 diabetes, glucosuria

Renal cell carcinoma in patient with crossed fused renal ectopia

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Ozgur Cakmak

2016-01-01

Full Text Available Primary renal cell carcinomas have rarely been reported in patients with crossed fused renal ectopia. We presented a patient with right to left crossed fused kidney harbouring renal tumor. The most frequent tumor encountered in crossed fused renal ectopia is renal cell carcinoma. In this case, partial nephrectomy was performed which pave way to preservation of the uninvolved both renal units. Due to unpredictable anatomy, careful preoperative planning and meticulous delineation of renal vasculature is essential for preservation of the uninvolved renal units.

ER stress and basement membrane defects combine to cause glomerular and tubular renal disease resulting from Col4a1 mutations in mice

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Frances E. Jones

2016-02-01

Full Text Available Collagen IV is a major component of basement membranes, and mutations in COL4A1, which encodes collagen IV alpha chain 1, cause a multisystemic disease encompassing cerebrovascular, eye and kidney defects. However, COL4A1 renal disease remains poorly characterized and its pathomolecular mechanisms are unknown. We show that Col4a1 mutations in mice cause hypotension and renal disease, including proteinuria and defects in Bowman's capsule and the glomerular basement membrane, indicating a role for Col4a1 in glomerular filtration. Impaired sodium reabsorption in the loop of Henle and distal nephron despite elevated aldosterone levels indicates that tubular defects contribute to the hypotension, highlighting a novel role for the basement membrane in vascular homeostasis by modulation of the tubular response to aldosterone. Col4a1 mutations also cause diabetes insipidus, whereby the tubular defects lead to polyuria associated with medullary atrophy and a subsequent reduction in the ability to upregulate aquaporin 2 and concentrate urine. Moreover, haematuria, haemorrhage and vascular basement membrane defects confirm an important vascular component. Interestingly, although structural and compositional basement membrane defects occurred in the glomerulus and Bowman's capsule, no tubular basement membrane defects were detected. By contrast, medullary atrophy was associated with chronic ER stress, providing evidence for cell-type-dependent molecular mechanisms of Col4a1 mutations. These data show that both basement membrane defects and ER stress contribute to Col4a1 renal disease, which has important implications for the development of treatment strategies for collagenopathies.

Na/K-ATPase Signaling and Salt Sensitivity: The Role of Oxidative Stress

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Jiang Liu

2017-03-01

Full Text Available Other than genetic regulation of salt sensitivity of blood pressure, many factors have been shown to regulate renal sodium handling which contributes to long-term blood pressure regulation and have been extensively reviewed. Here we present our progress on the Na/K-ATPase signaling mediated sodium reabsorption in renal proximal tubules, from cardiotonic steroids-mediated to reactive oxygen species (ROS-mediated Na/K-ATPase signaling that contributes to experimental salt sensitivity.

Overall renal and tubular function during infusion of amino acids in normal man

DEFF Research Database (Denmark)

Olsen, Niels Vidiendal; Hansen, J M; Ladefoged, S D

1990-01-01

sodium concentration] increased by 40% (P less than 0.001). Plasma renin concentration did not change significantly. 4. The results suggest that amino acids increase GFR by a primary effect on renal haemodynamics or, less likely, by reducing the signal to the tubuloglomerular feedback mechanism......1. Amino acids have been used to test renal reserve filtration capacity. Previous studies suggest that amino acids increase glomerular filtration rate (GFR) by reducing distal tubular flow and tubuloglomerular feedback activity. 2. Glomerular function and the renal tubular handling of sodium during...... infusion of amino acids was studied in 12 normal volunteers. 3. Clearance of sodium (CNa) was unchanged. Effective renal plasma flow increased slightly, but significantly, by 9% (P less than 0.05). GFR was increased by 13% (P less than 0.001). Clearance of lithium (CLi) (used as an index of proximal...

Chronic renal failure due to unilateral renal agenesis and total renal dysplasia (=aplasia)

International Nuclear Information System (INIS)

Kroepelin, T.; Ziupa, J.; Wimmer, B.

1983-01-01

Three adult patients with unilateral renal agenesis/total dysplasia (= aplasia) and with an early chronic renal failure are presented. One patient had renal agenesis without ureter bud and ureteric ostium on one side, and reflux pyelonephritis on the other; one had small compact total renal dysplasia (= aplasia) on one side, while chronic uric acid nephropathy (chronic renal disease as a cause of gout) was diagnosed on the other; the third patient had a total large multicystic dysplasia on one side, and on the other a segmental large multicystic dysplasia. Radiological steps and radiodiagnostic criteria are discussed and the combination of urogenital and extraurogenital anomalies is referred to. (orig.)

Efficacy of ultrasonography-guided renal biopsy for the evaluation of renal dysfunction following renal transplantation

International Nuclear Information System (INIS)

Kim, Young Jae; Choi, Chul Soon; Min, Seon Jeong; Lee, Gyung Kyu; Lee, Eil Seong; Kang, Ik Won; Bae, Sang Hoon

2003-01-01

To evaluate the usefulness and complications of renal biopsy under ultrasonography-guidance in renal dysfunction after renal transplantation. Ultrasonography-guided renal biopsy was done in 47 patients with the transplanted kidney. The subjects consisted of 30 males and 17 females, age ranged from 16 to 66 years (average age=38 years). Biopsies were done once in 27 patients, twice in 17 patients, three times in 3 patients, a total of 70 biopsies. The success rate of renal biopsy for the accurate pathologic diagnosis and the incidence and types of complications following biopsy were evaluated. The success rate of renal biopsy for the accurate pathologic diagnosis was 96%(67/70). Pathologic diagnosis included 27 cases of acute rejection (39%), 8 cases of acute tubular necrosis (11%), 4 cases of acute rejection and acute tubular necrosis (6%), 4 cases of cyclosporin toxicity (6%), 4 cases of primary disease recurrence (6%), 4 cases of infection (6%) and others. Complications after renal biopsy included 15 cases of microscopic hematuria (21%), 1 case of gross hematuria with spontaneous cessation and 1 case of life threatening hemorrhage. Ultrasonography-guided renal biopsy is a safe and effective diagnostic method for the evaluation of renal dysfunction following renal transplantation.

RNA sequencing of kidney distal tubule cells reveals multiple mediators of chronic aldosterone action

DEFF Research Database (Denmark)

Poulsen, Søren Brandt; Limbutara, Kavee; Fenton, Robert Andrew

2018-01-01

The renal aldosterone-sensitive distal tubule (ASDT) is crucial for sodium reabsorption and blood pressure regulation. The ASDT consists of the late distal convoluted tubule (DCT2), connecting tubule (CNT) and collecting duct. Due to difficulties in isolating epithelial cells from the ASDT in lar...

“Transcollateral” Renal Angioplasty for a Completely Occluded Renal Artery

International Nuclear Information System (INIS)

Chandra, Subash; Chadha, Davinder S.; Swamy, Ajay

2011-01-01

Percutaneous transluminal renal angioplasty with stenting has been effective in the control of hypertension, renal function, and pulmonary edema caused by atherosclerotic renal artery stenosis. However, the role of the procedure has not been fully established in the context of chronic total occlusion of renal artery. We report the successful use of this procedure in 57-year-old male patient who reported for evaluation of a recent episode of accelerated hypertension. A renal angiogram in this patient showed ostial stenosis of the right renal artery, which was filling by way of the collateral artery. Renal angioplasty for chronic total occlusion of right renal artery was successfully performed in a retrograde fashion through a collateral artery, thereby leading to improvement of renal function and blood pressure control.

GPER Mediates Functional Endothelial Aging in Renal Arteries.

Science.gov (United States)

Meyer, Matthias R; Rosemann, Thomas; Barton, Matthias; Prossnitz, Eric R

2017-01-01

Aging is associated with impaired renal artery function, which is partly characterized by arterial stiffening and a reduced vasodilatory capacity due to excessive generation of reactive oxygen species by NADPH oxidases (Nox). The abundance and activity of Nox depends on basal activity of the heptahelical transmembrane receptor GPER; however, whether GPER contributes to age-dependent functional changes in renal arteries is unknown. This study investigated the effect of aging and Nox activity on renal artery tone in wild-type and GPER-deficient (Gper-/-) mice (4 and 24 months old). In wild-type mice, aging markedly impaired endothelium-dependent, nitric oxide (NO)-mediated relaxations to acetylcholine, which were largely preserved in renal arteries of aged Gper-/- mice. The Nox inhibitor gp91ds-tat abolished this difference by greatly enhancing relaxations in wild-type mice, while having no effect in Gper-/- mice. Contractions to angiotensin II and phenylephrine in wild-type mice were partly sensitive to gp91ds-tat but unaffected by aging. Again, deletion of GPER abolished effects of Nox inhibition on contractile responses. In conclusion, basal activity of GPER is required for the age-dependent impairment of endothelium-dependent, NO-mediated relaxation in the renal artery. Restoration of relaxation by a Nox inhibitor in aged wild-type but not Gper-/- mice strongly supports a role for Nox-derived reactive oxygen species as the underlying cause. Pharmacological blockers of GPER signaling may thus be suitable to inhibit functional endothelial aging of renal arteries by reducing Nox-derived oxidative stress and, possibly, the associated age-dependent deterioration of kidney function. © 2017 S. Karger AG, Basel.

Anaemia management in cardio renal disease.

Science.gov (United States)

Silverberg, Donald S; Wexler, Dov; Iaina, Adrian; Schwartz, Doron

2010-05-01

Anaemia is common in congestive heart failure (CHF) and is associated with increased mortality, morbidity and progressive renal failure. The common causes of the anaemia are the associated renal failure and excessive cytokine production, both of which can cause depression of the erythropoietin (EPO) production in the kidney and depression of EPO response in bone marrow. The cytokines can also induce iron deficiency by increasing hepcidin production from the liver, which both reduces gastrointestinal iron absorption and reduces iron release from iron stores located in the macrophages and hepatocytes. Attempts to control this anaemia will have to consider the use of both erythropoiesis stimulating agents (ESA) as well as oral and, probably more importantly, intravenous (IV) iron. Studies of anaemia in CHF with ESA and oral or IV iron and even with IV iron alone have shown a positive effect on hospitalisation, fatigue and shortness of breath, cardiac and renal function, quality-of-life, exercise capacity and reduced beta natriuretic peptide and have not demonstrated an increase in cardiovascular damage related to therapy. Although some studies and meta-analyses have revealed improvement in these parameters others have not. Adequately powered long-term placebo-controlled studies of ESA and of IV iron in CHF are needed and are currently being carried out.

The mythology of renal function measurement

International Nuclear Information System (INIS)

Britton, K.E.

2003-01-01

The kidney is a conservative organ. In principle it retains what the body needs, and what is not needed is excreted. It has a number of basic properties. It has the ability to take solutes up from the blood whether by filtration or secretion, which is best called its Uptake function. In the special circumstance where the kidneys are the only exit for the solute from the body, then the rate of loss from the blood is equal to the rate of uptake by the kidney. It has the ability to move solutes among its nephrons, which is its Transit function. The solutes may be absorbed in whole or part and be retained or returned to the blood, its Reabsorption function. In the special case where the solute is non- reabsorbable, then, if there is an increase in salt and water reabsorption as in functionally significant renovascular disease or obstructive nephropathy, the transit function is altered and the transit time through the parenchyme is prolonged. In renovascular disorder the transit time is prolonged through both cortical and juxta-medullary nephrons and collecting ducts. In obstructive nephropathy the transit time is prolonged through the cortical nephrons, but usually is shortened through the juxta-medullary nephrons and collecting ducts due to loss of medullary concentrating ability. After transit through the kidney, the solutes move through the pelvis and ureter, its Excretory function. No more can come out of the kidney then went in previously. If less comes out than what went in, then an increased resistance to outflow is predicted. The balance between excretory function and uptake function is measurable by the Output (Outflow) Efficiency. The kidney also has receptors for hormones, which may modify its reabsorptive functions, for example increased Vasopressin binding decreases the permeability of the collecting duct to water. The kidney also has the ability through enzymes to modify solutes, such as the activation of Vitamin D

Influences of renal stone surgeries on renal function; Evaluation of renal function with sup 99m Tc-DMSA renal scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Katayama, Yasushi (Niigata Univ. (Japan). School of Medicine)

1991-10-01

From 1984 to 1990, {sup 99m}Tc-DMSA renal scintigraphy was performed before and after nephrolithotomy (15 cases), pyelolithotomy (15 cases), percutaneous nephrolithotripsy (PNL: 15 cases) and extracorporeal shock wave lithotripsy (ESWL: 16 cases, 17 kidneys) in order to evaluate of influences of renal stone surgeries on split renal function. DMSA renal uptake change ratio of treated kidneys of nephrolithotomy (-24.94{+-}5.60%) was significantly lower than that of PNL (-0.06{+-}3.92%), pyelolithotomy (-4.08{+-}4.79%) (p<0.01) and ESWL (-7.72{+-}3.87%) (p<0.05). The average change ratios of contralateral kidneys were as follows: PNL 4.80{+-}4.21% nephrolithotomy 4.67{+-}4.73%, pyelolithotomy -1.46{+-}5.39% and ESWL -2.02{+-}4.44%. One to 3 weeks after PNL, the cold area on the renal image was found in 10 (66.7%) of 15 cases. In cases of ESWL, DMSA renal uptake decreased even 4-10 weeks (mean 7 weeks) after treatment. In conclusion, possibility of deterioration of renal function after ESWL was suggested. (author).

Renal Osteodystrophy

Directory of Open Access Journals (Sweden)

Aynur Metin Terzibaşoğlu

2004-12-01

Full Text Available Chronic renal insufficiency is a functional definition which is characterized by irreversible and progressive decreasing in renal functions. This impairment is in collaboration with glomeruler filtration rate and serum creatinine levels. Besides this, different grades of bone metabolism disorders develop in chronic renal insufficiency. Pathologic changes in bone tissue due to loss of renal paranchyme is interrelated with calcium, phosphorus vitamine-D and parathyroid hormone. Clinically we can see high turnover bone disease, low turnover bone disease, osteomalacia, osteosclerosis and osteoporosis in renal osteodystropy. In this article we aimed to review pathology of bone metabolism disorders due to chronic renal insufficiency, clinic aspects and treatment approaches briefly.

Early life stress sensitizes the renal and systemic sympathetic system in rats.

Science.gov (United States)

Loria, Analia S; Brands, Michael W; Pollock, David M; Pollock, Jennifer S

2013-08-01

We hypothesized that maternal separation (MS), an early life stress model, induces a sensitization of the sympathetic system. To test this hypothesis, we evaluated the renal and systemic sympathetic system in 12- to 14-wk-old male control or MS rats with the following parameters: 1) effect of renal denervation on conscious renal filtration capacity, 2) norepinephrine (NE) content in key organs involved in blood pressure control, and 3) acute systemic pressor responses to adrenergic stimulation or ganglion blockade. MS was performed by separating pups from their mothers for 3 h/day from day 2 to 14; controls were nonhandled littermates. Glomerular filtration rate (GFR) was examined in renal denervated (DnX; within 2 wk) or sham rats using I¹²⁵-iothalamate plasma clearance. MS-DnX rats showed significantly increased GFR compared with MS-SHAM rats (3.8 ± 0.4 vs. 2.4 ± 0.2 ml/min, respectively, P renal nerves regulate GFR in MS rats. NE content was significantly increased in organ tissues from MS rats (P renal and systemic sympathetic system. Conscious MS rats displayed a significantly greater increase in mean arterial pressure (MAP) in response to NE (2 μg/kg ip) and a greater reduction in MAP in response to mecamylamine (2 mg/kg ip, P renal and systemic sympathetic system ultimately impairing blood pressure regulation.

A study of nephron function in normal tropical residents using the creatinine and lithium clearances

Science.gov (United States)

Arthur, S. K.; Nyarko, A. K.; Asaku, J. Y.; Akyeampong, A. Y.

The kidney bears the brunt of the demands of a tropical climate for water and electrolyte homeostasis. We hypothesised that a tropical climate may cause adaptive changes in the entire organism leading to altered renal function in our subjects. Hence renal function data for residents of a temperate climate may not be applic- able to tropical residents. We therefore sought to elucidate renal function in subjects residing in a tropical climate. We used lithium clearance, CLi, a non-invasive tool for assessing proximal tubular function in humans, and endogenous creatinine clearance, CCr, to estimate proximal tubular function and glomerular function, respectively, in our subjects. We did this in order to establish whether or not nephron function in our subjects differs from that for residents of a temperate climate. Nineteen male and 12 female Ghanaian subjects aged between 15 and 48 years were studied. The estimated GCr was 117.3+/-6.6 ml/min for male subjects and 97+/-6.4 ml/min for female subjects. CLi was 20.3+/-1.6 ml/min for male and 19.1+/-0.4 ml/min for female subjects, respectively. The estimated absolute reabsorption rate of fluid of proximal tubules was 97.0+/-6.0 ml/min for males and 78.1+/-6.0 ml/min for females. The percentage proximal fluid reabsorption for male and female subjects was 81.2+/-1.4 and 79.5+/-1.6, respectively. The differences between male and female values (mean+/-SEM) were not statistically significant. The data suggest that the proximal tubule in residents of a tropical climate may reabsorb more fluid compared to that in residents of a temperate climate. Our values for proximal tubular reabsorption are higher than those reported for residents of a temperature climate. Our estimate of glomerular filtration, however, is similar to published data for Caucasians. The difference in proximal tubular function may reflect possible renal adaptation to a hot, humid climate. We conclude that renal function of tropical residents differs from that of

CT differentiation of infiltrating renal cell carcinoma and renal urothelial tumor

International Nuclear Information System (INIS)

Choi, Hyo Kyeong; Goo, Dong Erk; Bang, Sun Woo; Lee, Moon Gyu; Cho, Kyoung Sik; Auh, Yong Ho

1994-01-01

It may be difficult to differentiate renal cell carcinoma involving collecting system from renal urothelial tumor invading into renal parenchyma. The purpose of this study was to assess the differences of CT findings between two conditions. CT findings of 5 cases of renal cell carcinoma involving the renal collecting systems and 10 cases of renal urothelial tumors invading the renal parenchyma were compared, and analyzed about the presence or absence of hydronephrosis, normal or abnormal CT nephrogram, renal contour changes due to mass and tentative diagnosis. The diagnoses were confirmed at surgery. Renal cell carcinoma showed hydronephrosis in only 20% and normal CT nephrogram and outward contour bulging in all cases. In contrast, renal urothelial tumor showed hydronephrosis(70%), abnormal CT nephrogram(60%), and preservation of reinform shape(100%). Renal contour changes and CT nephrogram may be useful in distinguishing both disease entities

Urinary excretion of Tamm-Horsfall protein and epidermal growth factor in chronic nephropathy

DEFF Research Database (Denmark)

Torffvit, O; Jørgensen, P E; Kamper, A L

1998-01-01

rate (GFR) as an indicator for the general renal function, lithium clearance (C(Li)) as an indicator for proximal tubular function, and absolute distal reabsorption of sodium (ADR(Na)) as an indicator for distal tubular function. The excretion rate of EGF was rather closely correlated with GFR, C......(Li) and ADR(Na) (Spearman coefficients of variation 0.88, 0.69, and 0.74, respectively). The correlations between the excretion rate of THP and GFR, C(Li) and ADR(Na) were weaker (Spearman coefficients of variation 0.68, 0.42, and 0.44). When the effect of GFR had been accounted for by multiple variance...... analyses, the excretion rates of the two peptides were still associated with ADR(Na) but not with C(Li). In conclusion, the urinary excretion rates of especially EGF but also those of THP were correlated with renal function and distal tubular reabsorption of sodium in patients with chronic nephropathy....

Hyperactivation of Nrf2 in early tubular development induces nephrogenic diabetes insipidus

Science.gov (United States)

Suzuki, Takafumi; Seki, Shiori; Hiramoto, Keiichiro; Naganuma, Eriko; Kobayashi, Eri H.; Yamaoka, Ayaka; Baird, Liam; Takahashi, Nobuyuki; Sato, Hiroshi; Yamamoto, Masayuki

2017-01-01

NF-E2-related factor-2 (Nrf2) regulates cellular responses to oxidative and electrophilic stress. Loss of Keap1 increases Nrf2 protein levels, and Keap1-null mice die of oesophageal hyperkeratosis because of Nrf2 hyperactivation. Here we show that deletion of oesophageal Nrf2 in Keap1-null mice allows survival until adulthood, but the animals develop polyuria with low osmolality and bilateral hydronephrosis. This phenotype is caused by defects in water reabsorption that are the result of reduced aquaporin 2 levels in the kidney. Renal tubular deletion of Keap1 promotes nephrogenic diabetes insipidus features, confirming that Nrf2 activation in developing tubular cells causes a water reabsorption defect. These findings suggest that Nrf2 activity should be tightly controlled during development in order to maintain renal homeostasis. In addition, tissue-specific ablation of Nrf2 in Keap1-null mice might create useful animal models to uncover novel physiological functions of Nrf2. PMID:28233855

The renal scan in pregnant renal transplant patients

International Nuclear Information System (INIS)

Goldstein, H.A.; Ziessman, H.A.; Fahey, F.H.; Collea, J.V.; Alijani, M.R.; Helfrich, G.B.

1985-01-01

With the greater frequency of renal transplant surgery, more female pts are becoming pregnant and carrying to term. In the renal allograft blood vessels and ureter may be compressed resulting in impaired renal function and/or, hypertension. Toxemia of pregnancy is seen more frequently than normal. Radionuclide renal scan monitoring may be of significant value in this high risk obstetrical pt. After being maintained during the pregnancy, renal function may also deteriorate in the post partum period. 5 pregnant renal transplant pts who delivered live babies had renal studies with Tc-99m DTPA to assess allograft perfusion and function. No transplanted kidney was lost during or after pregnancy as a result of pregnancy. No congenital anomalies were associated with transplant management. 7 studies were performed on these 5 pts. The 7 scans all showed the uterus/placenta. The bladder was always distorted. The transplanted kidney was rotated to a more vertical position in 3 pts. The radiation dose to the fetus is calculated at 0.024 rad/mCi administered. This study demonstrates the anatomic and physiologic alterations expected in the transplanted kidney during pregnancy when evaluated by renal scan and that the radiation burden may be acceptable in management of these pts

Renal deterioration after spinal cord injury is associated with length of detrusor contractions during cystometry

DEFF Research Database (Denmark)

Elmelund, Marlene; Klarskov, Niels; Bagi, Per

2017-01-01

AIMS: To investigate which urodynamic parameters are associated with renal deterioration over a median of 41 years follow-up after traumatic spinal cord injury. METHODS: Medical records of patients with a traumatic spinal cord injury sustained 1944-1975 were reviewed from time of injury until 2012....... Patients who attended regular renography and/or renal clearance examinations and had minimum one cystometry and pressure-flow study were included. Renal deterioration was diagnosed as split renal function ≤30% in one kidney or relative glomerular filtration rate ≤51% of expected according to age and gender....... Detrusor function, presence of detrusor sphincter dyssynergia, maximum detrusor pressure, post-void residual volume, and cystometric bladder capacity were obtained. In patients with detrusor overactivity, a detrusor overactivity/cystometry ratio was calculated using duration of detrusor contraction...

Increased Urinary Extracellular Vesicle Sodium Transporters in Cushing's Syndrome with Hypertension.

Science.gov (United States)

Salih, Mahdi; Bovée, Dominique M; van der Lubbe, Nils; Danser, Alexander H J; Zietse, Robert; Feelders, Richard A; Hoorn, Ewout J

2018-05-02

Increased renal sodium reabsorption contributes to hypertension in Cushing's syndrome (CS). Renal sodium transporters can be analyzed non-invasively in urinary extracellular vesicles (uEVs). To analyze renal sodium transporters in uEVs of patients with CS and hypertension. Observational study. University hospital. uEVs were isolated by ultracentrifugation and analyzed by immunoblotting in 10 CS patients and 7 age-matched healthy subjects. In 7 CS patients uEVs were analyzed before and after treatment. uEV protein abundance. The 10 CS patients were divided in those with suppressed and non-suppressed renin-angiotensin-aldosterone system (RAAS, n = 5/group). CS patients with suppressed RAAS had similar blood pressure but significantly lower serum potassium than CS patients with non-suppressed RAAS. Compared to healthy subjects, only those with suppressed RAAS had higher phosphorylated Na+-K+-Cl- cotransporter type 2 (pNKCC2) and higher total and phosphorylated Na+-Cl- cotransporter (NCC) in uEVs. Serum potassium but not urinary free cortisol correlated with pNKCC2, pNCC, and NCC in uEVs. Treatment of CS reversed the increases in pNKCC2, NCC, and pNCC. CS increases renal sodium transporter abundance in uEVs especially in patients with hypertension and suppressed RAAS. As potassium has recently been identified as an important driver of NCC activity, low serum potassium may also contribute to increased renal sodium reabsorption and hypertension in CS. These results may also be relevant for hypertension induced by exogenous glucocorticoids.

Structure and chromosomal localization of the human renal kallikrein gene

International Nuclear Information System (INIS)

Evans, B.A.; Yun, Z.X.; Close, J.A.

1988-01-01

Glandular kallikreins are a family of proteases encoded by a variable number of genes in different mammalian species. In all species examined, however, one particular kallikrein is functionally conserved in its capacity to release the vasoactive peptide, Lys-bradykinin, from low molecular weight kininogen. This kallikrein is found in the kidney, pancreas, and salivary gland, showing a unique pattern of tissue-specific expression relative to other members of the family. The authors have isolated a genomic clone carrying the human renal kallikrein gene and compared the nucleotide sequence of its promoter region with those of the mouse renal kallikrein gene and another mouse kallikrein gene expressed in a distinct cell type. They find four sequence elements conserved between renal kallikrein genes from the two species. They have also shown that the human gene is localized to 19q13, a position analogous to that of the kallikrein gene family on mouse chromosome 7

Renal perfusion scintiscan

Science.gov (United States)

... Radionuclide renal perfusion scan; Perfusion scintiscan - renal; Scintiscan - renal perfusion Images Kidney anatomy Kidney - blood and urine flow Intravenous pyelogram References Rottenberg G, Andi AC. Renal ...

Probing SGLT2 as a therapeutic target for diabetes: Basic physiology and consequences

Science.gov (United States)

Gallo, Linda A; Wright, Ernest M; Vallon, Volker

2018-01-01

Traditional treatments for type 1 and type 2 diabetes are often associated with side effects, including weight gain and hypoglycaemia that may offset the benefits of blood glucose lowering. The kidneys filter and reabsorb large amounts of glucose, and urine is almost free of glucose in normoglycaemia. The sodium-dependent glucose transporter (SGLT)-2 in the early proximal tubule reabsorbs the majority of filtered glucose. Remaining glucose is reabsorbed by SGLT1 in the late proximal tubule. Diabetes enhances renal glucose reabsorption by increasing the tubular glucose load and the expression of SGLT2 (as shown in mice), which maintains hyperglycaemia. Inhibitors of SGLT2 enhance urinary glucose excretion and thereby lower blood glucose levels in type 1 and type 2 diabetes. The load-dependent increase in SGLT1-mediated glucose reabsorption explains why SGLT2 inhibitors in normoglycaemic conditions only excrete ~50% of the filtered glucose. The role of SGLT1 in both renal and intestinal glucose reabsorption provides a rationale for the development of dual SGLT1/2 inhibitors. SGLT2 inhibitors lower blood glucose levels independent of insulin and induce pleiotropic actions that may be relevant in the context of lowering cardiovascular risk. Ongoing long-term clinical studies will determine whether SGLT2 inhibitors have a safety profile and exert cardiovascular benefits that are superior to traditional agents. PMID:25616707

SGLT2 inhibition in the diabetic kidney – an update

Science.gov (United States)

Novikov, Aleksandra; Vallon, Volker

2016-01-01

Purpose of review The sodium glucose cotransporter SGLT2 reabsorbs most of the glucose filtered by the kidneys. SGLT2 inhibitors reduce glucose reabsorption thereby lowering blood glucose levels and have been approved as new anti-hyperglycemic drugs. While the therapeutic strategy is very promising, many questions remain. Recent findings Using validated antibodies SGLT2 expression was localized to the brush border of the early proximal tubule in human kidney and was found upregulated in genetic murine models of type 1 and 2 diabetes. SGLT2 may functionally interact with the Na/H exchanger NHE3 in the proximal tubule. SGLT1-mediated reabsorption explains the fractional glucose reabsorption of 40–50% during SGLT2 inhibition. SGLT2 is expressed on pancreatic alpha cells where its inhibition induces glucagon secretion. SGLT2 inhibition lowers GFR in hyperfiltering diabetic patients consistent with the tubular hypothesis of diabetic hyperfiltration. New data indicate a potential of SGLT2 inhibition for renal medullary hypoxia and ketoacidosis, but also for blood glucose effect-dependent and independent nephroprotective actions, renal gluconeogenesis inhibition, reduction in cardiovascular mortality, and cancer therapy. Summary The findings expand and refine our understanding of SGLT2 and its inhibition, have relevance for clinical practice, and will help interpret ongoing clinical trials on the long-term safety and cardiovascular effects of SGLT2 inhibitors. PMID:26575393

Study of acute renal insufficiency and chronic renal insufficiency using radioisotopes

International Nuclear Information System (INIS)

Raynaud, C.

1976-01-01

Radioisotopic renal function tests are of assistance to diagnose and follow-up the course of renal insufficiency. The radioisotopic renogram is useful in assessing the response to therapy of child obstructive uropathies and evaluating renal transplant function. The renal scan is helpful, in an emergency service, to differenciate chronic renal insufficiency from acute renal insufficiency. Hg renal uptake test provides informations on physiopathological problems. Among them, the following problems are emphasized: evolution of a nonfunctioning kidney, control of the success of a reparative surgery and of bilateral obstructive uropathies with unilateral symptoms [fr

Distal renal tubular acidosis in recurrent renal stone formers

DEFF Research Database (Denmark)

Osther, P J; Hansen, A B; Røhl, H F

1989-01-01

Renal acidification ability was examined in 90 recurrent renal stone formers, using fasting morning urinary pH levels followed by a short ammonium chloride loading test in subjects with pH levels above 6.0. Fifteen patients (16.6%) revealed a distal renal tubular acidification defect: one patient......, this has important therapeutic implications. The pathological sequence in renal stone formers with dRTA is discussed....

Screening renal stone formers for distal renal tubular acidosis

DEFF Research Database (Denmark)

Osther, P J; Hansen, A B; Røhl, H F

1989-01-01

A group of 110 consecutive renal stone formers were screened for distal renal tubular acidosis (RTA) using morning fasting urinary pH (mfUpH) levels followed by a short ammonium chloride loading test in patients with levels above 6.0. In 14 patients (12.7%) a renal acidification defect was noted...... RTA in renal stone formers. Regardless of whether the acidification defect is primary or secondary to stone formation, however, all renal stone formers with distal RTA can expect to benefit from prophylactic alkaline therapy and it is recommended that the screening procedure, which is easy to use...

Acute renal infarction Secondary to Atrial Fibrillation Mimicking Renal Stone Picture

International Nuclear Information System (INIS)

Salih, Salih Bin; Al-Durihim, H.; Al-Jizeeri, A.; Al-Maziad, G.

2006-01-01

Acute renal infarction presents in a similar clinical picture to that of a renal stone. We report a 55-year-old Saudi female, known to have atrial fibrillation secondary to mitral stenosis due to rheumatic heart disease. She presented with a two day history of right flank pain that was treated initially as renal stone. Further investigations confirmed her as a case of renal infarction. Renal infarction is under-diagnosed because the similarity of its presentation to renal stone. Renal infarction should be considered in the differential diagnosis of loin pain, particularly in a patient with atrial fibrillation. (author)

Results, meta-analysis and a first evaluation of UNOxR, the urinary nitrate-to-nitrite molar ratio, as a measure of nitrite reabsorption in experimental and clinical settings.

Science.gov (United States)

Tsikas, Dimitrios; Hanff, Erik; Bollenbach, Alexander; Kruger, Ruan; Pham, Vu Vi; Chobanyan-Jürgens, Kristine; Wedekind, Dirk; Arndt, Tanja; Jörns, Anne; Berbée, Jimmy F P; Princen, Hans M G; Lücke, Thomas; Mariotti, François; Huneau, Jean-François; Ückert, Stefan; Frölich, Jürgen C; Lenzen, Sigurd

2018-05-04

We recently found that renal carbonic anhydrase (CA) is involved in the reabsorption of inorganic nitrite (NO 2 - ), an abundant reservoir of nitric oxide (NO) in tissues and cells. Impaired NO synthesis in the endothelium and decreased NO bioavailability in the circulation are considered major contributors to the development and progression of renal and cardiovascular diseases in different conditions including diabetes. Isolated human and bovine erythrocytic CAII and CAIV can convert nitrite to nitrous acid (HONO) and its anhydride N 2 O 3 which, in the presence of thiols (RSH), are further converted to S-nitrosothiols (RSNO) and NO. Thus, CA may be responsible both for the homeostasis of nitrite and for its bioactivation to RSNO/NO. We hypothesized that enhanced excretion of nitrite in the urine may contribute to NO-related dysfunctions in the renal and cardiovascular systems, and proposed the urinary nitrate-to-nitrite molar ratio, i.e., U NOx R, as a measure of renal CA-dependent excretion of nitrite. Based on results from clinical and experimental animal studies, here, we report on a first evaluation of U NOx R. We determined U NOx R values in preterm neonates, healthy children, and adults, in children suffering from type 1 diabetes mellitus (T1DM) or Duchenne muscular dystrophy (DMD), in elderly subjects suffering from chronic rheumatic diseases, type 2 diabetes mellitus (T2DM), coronary artery disease (CAD), or peripheral arterial occlusive disease (PAOD). We also determined U NOx R values in healthy young men who ingested isosorbide dinitrate (ISDN), pentaerythrityl tetranitrate (PETN), or inorganic nitrate. In addition, we tested the utility of U NOx R in two animal models, i.e., the LEW.1AR1-iddm rat, an animal model of human T1DM, and the APOE*3-Leiden.CETP mice, a model of human dyslipidemia. Mean U NOx R values were lower in adult patients with rheumatic diseases (187) and in T2DM patients of the DALI study (74) as compared to healthy elderly adults

Role of bone marrow-derived stem cells, renal progenitor cells and stem cell factor in chronic renal allograft nephropathy

Directory of Open Access Journals (Sweden)

Hayam Abdel Meguid El Aggan

2013-09-01

Full Text Available Introduction: Chronic allograft nephropathy (CAN is a poorly understood clinico-pathological entity associated with chronic allograft loss due to immunologic and non-immunologic causes. It remains the leading cause of late allograft loss. Bone marrow derived stem cells are undifferentiated cells typically characterized by their capacity for self renewal, ability to give rise to multiple differentiated cellular population, including hematopoietic (HSCs and mesenchymal stem cells (MSCs. Characterization of HSCs includes their multipotency, expression of typical surface markers such as CD34 and CD45, while characterization of MSC includes their multipotency, expression of typical surface markers such as CD90 and CD105, and the absence of hemopoietic lineage markers. Aim & methods: The aim of the present work was to study the role of bone marrow-derived HSCs and MSCs, renal progenitor cells and SCF in chronic renal allograft nephropathy in relation to renal hemodynamics and histopathological changes. We studied 30 patients with kidney transplantation for more than 6 months, divided into 15 patients with stable serum creatinine and 15 patients who developed CAN. Detection of HSCs and MSCs in the peripheral blood using flow cytometry via detection of CD34, CD45, CD117 and CD106, as well as immunohistochemical detection of CD34, CD133, VEGF and αSMA in transplanted kidney biopsies of patients with CAN were done. Results: There was a significant increase in the levels of SCF, number of peripheral blood HSCs and MSCs in both transplanted patient groups than the controls and they were higher in patients of group Ia than patients of group Ib, (F = 39.73, P < 0.001, (F = 13.28, P < 0.001, (F = 11.94, P < 0.001, respectively and this was accompanied by evident expression of markers of renal repair. Conclusion: Stem cells might have a role in renal regeneration in CAN and this may pave the way toward the use of stem cells in correction of CAN. KEYWORDS

SGLT2 inhibitor empagliflozin reduces renal growth and albuminuria in proportion to hyperglycemia and prevents glomerular hyperfiltration in diabetic Akita mice

Science.gov (United States)

Gerasimova, Maria; Rose, Michael A.; Masuda, Takahiro; Satriano, Joseph; Mayoux, Eric; Koepsell, Hermann; Thomson, Scott C.; Rieg, Timo

2013-01-01

Our previous work has shown that gene knockout of the sodium-glucose cotransporter SGLT2 modestly lowered blood glucose in streptozotocin-diabetic mice (BG; from 470 to 300 mg/dl) and prevented glomerular hyperfiltration but did not attenuate albuminuria or renal growth and inflammation. Here we determined effects of the SGLT2 inhibitor empagliflozin (300 mg/kg of diet for 15 wk; corresponding to 60–80 mg·kg−1·day−1) in type 1 diabetic Akita mice that, opposite to streptozotocin-diabetes, upregulate renal SGLT2 expression. Akita diabetes, empagliflozin, and Akita + empagliflozin similarly increased renal membrane SGLT2 expression (by 38–56%) and reduced the expression of SGLT1 (by 33–37%) vs. vehicle-treated wild-type controls (WT). The diabetes-induced changes in SGLT2/SGLT1 protein expression are expected to enhance the BG-lowering potential of SGLT2 inhibition, and empagliflozin strongly lowered BG in Akita (means of 187–237 vs. 517–535 mg/dl in vehicle group; 100–140 mg/dl in WT). Empagliflozin modestly reduced GFR in WT (250 vs. 306 μl/min) and completely prevented the diabetes-induced increase in glomerular filtration rate (GFR) (255 vs. 397 μl/min). Empagliflozin attenuated increases in kidney weight and urinary albumin/creatinine ratio in Akita in proportion to hyperglycemia. Empagliflozin did not increase urinary glucose/creatinine ratios in Akita, indicating the reduction in filtered glucose balanced the inhibition of glucose reabsorption. Empagliflozin attenuated/prevented the increase in systolic blood pressure, glomerular size, and molecular markers of kidney growth, inflammation, and gluconeogenesis in Akita. We propose that SGLT2 inhibition can lower GFR independent of reducing BG (consistent with the tubular hypothesis of diabetic glomerular hyperfiltration), while attenuation of albuminuria, kidney growth, and inflammation in the early diabetic kidney may mostly be secondary to lower BG. PMID:24226524

The Effects of Renal Denervation on Renal Hemodynamics and Renal Vasculature in a Porcine Model.

Directory of Open Access Journals (Sweden)

Willemien L Verloop

Full Text Available Recently, the efficacy of renal denervation (RDN has been debated. It is discussed whether RDN is able to adequately target the renal nerves.We aimed to investigate how effective RDN was by means of functional hemodynamic measurements and nerve damage on histology.We performed hemodynamic measurements in both renal arteries of healthy pigs using a Doppler flow and pressure wire. Subsequently unilateral denervation was performed, followed by repeated bilateral hemodynamic measurements. Pigs were terminated directly after RDN or were followed for 3 weeks or 3 months after the procedure. After termination, both treated and control arteries were prepared for histology to evaluate vascular damage and nerve damage. Directly after RDN, resting renal blood flow tended to increase by 29±67% (P = 0.01. In contrast, renal resistance reserve increased from 1.74 (1.28 to 1.88 (1.17 (P = 0.02 during follow-up. Vascular histopathology showed that most nerves around the treated arteries were located outside the lesion areas (8±7 out of 55±25 (14% nerves per pig were observed within a lesion area. Subsequently, a correlation was noted between a more impaired adventitia and a reduction in renal resistance reserve (β: -0.33; P = 0.05 at three weeks of follow-up.Only a small minority of renal nerves was targeted after RDN. Furthermore, more severe adventitial damage was related to a reduction in renal resistance in the treated arteries at follow-up. These hemodynamic and histological observations may indicate that RDN did not sufficiently target the renal nerves. Potentially, this may explain the significant spread in the response after RDN.

The Effects of Renal Denervation on Renal Hemodynamics and Renal Vasculature in a Porcine Model

Science.gov (United States)

Verloop, Willemien L.; Hubens, Lisette E. G.; Spiering, Wilko; Doevendans, Pieter A.; Goldschmeding, Roel; Bleys, Ronald L. A. W.; Voskuil, Michiel

2015-01-01

Rationale Recently, the efficacy of renal denervation (RDN) has been debated. It is discussed whether RDN is able to adequately target the renal nerves. Objective We aimed to investigate how effective RDN was by means of functional hemodynamic measurements and nerve damage on histology. Methods and Results We performed hemodynamic measurements in both renal arteries of healthy pigs using a Doppler flow and pressure wire. Subsequently unilateral denervation was performed, followed by repeated bilateral hemodynamic measurements. Pigs were terminated directly after RDN or were followed for 3 weeks or 3 months after the procedure. After termination, both treated and control arteries were prepared for histology to evaluate vascular damage and nerve damage. Directly after RDN, resting renal blood flow tended to increase by 29±67% (P = 0.01). In contrast, renal resistance reserve increased from 1.74 (1.28) to 1.88 (1.17) (P = 0.02) during follow-up. Vascular histopathology showed that most nerves around the treated arteries were located outside the lesion areas (8±7 out of 55±25 (14%) nerves per pig were observed within a lesion area). Subsequently, a correlation was noted between a more impaired adventitia and a reduction in renal resistance reserve (β: -0.33; P = 0.05) at three weeks of follow-up. Conclusion Only a small minority of renal nerves was targeted after RDN. Furthermore, more severe adventitial damage was related to a reduction in renal resistance in the treated arteries at follow-up. These hemodynamic and histological observations may indicate that RDN did not sufficiently target the renal nerves. Potentially, this may explain the significant spread in the response after RDN. PMID:26587981

Renal pathological implications in type 2 diabetes mellitus patients with renal involvement.

Science.gov (United States)

Li, Li; Zhang, Xiuhui; Li, Zhicheng; Zhang, Rui; Guo, Ruikun; Yin, Qinghua; Yang, Lichuan; Yue, Rongzheng; Su, Baihai; Huang, Songmin; Xu, Huan; He, Cijiang; Liu, Fang

2017-01-01

To investigate the renal pathological implications in type 2 diabetes mellitus patients with renal involvement. A total of 328 type 2 diabetes mellitus (T2DM) patients with renal involvement who underwent a renal biopsy and received follow-up for at least one year were recruited in our study. The patients were divided into the diabetic nephropathy (DN), non-diabetic renal disease (NDRD), and NDRD superimposed on DN groups based on the pathological diagnosis. Renal outcomes were defined by the initiation of renal replacement therapy or doubling of the serum creatinine. Kaplan-Meier analysis was used to compare renal survival, and Cox proportional hazard analysis was used to determine the predictors of renal outcomes in the DN group. Renal biopsy findings revealed that 188 patients (57.32%) had pure DN, 121 patients (36.89%) had NDRD alone, and 19 patients (5.79%) had NDRD superimposed on DN. The most frequent subclassification of NDRD was membranous nephropathy (MN). Compared with the NDRD and NDRD superimposed on DN groups, patients with pure DN had poorer renal function and lower renal survival rates. In the DN group, the five-year renal survival rates of glomerular classes of I, IIa, IIb, III and IV were 100%, 84.62%, 60%, 47.5% and 33.33%, respectively. Multivariate Cox proportional hazard analysis showed that the glomerular lesions, proteinuria and serum creatinine were independent risk factors for renal outcomes, while interstitial fibrosis/inflammation and arteriolar hyalinosis were not independently associated with renal outcomes in the DN group. Making an accurate pathologic diagnosis by renal biopsy is crucial for diabetes mellitus (DM) patients with renal involvement. The findings of our present study indicated that patients with pure DN had poorer renal outcomes than patients with NDRD or NDRD superimposed on DN. The classification of glomerular lesions, proteinuria and serum creatinine were independent risk factors for renal outcomes in the DN group

Detection of acute renal allograft rejection by analysis of renal tissue proteomics in rat models of renal transplantation

Directory of Open Access Journals (Sweden)

Dai Yong

2008-01-01

Full Text Available At present, the diagnosis of renal allograft rejection requires a renal biopsy. Clinical management of renal transplant patients would be improved if rapid, noninvasive and reliable biomarkers of rejection were available. This study is designed to determine whether such protein biomarkers can be found in renal-graft tissue proteomic approach. Orthotopic kidney transplantations were performed using Fisher (F344 or Lewis rats as donors and Lewis rats as recipients. Hence, there were two groups of renal transplant models: one is allograft (from F344 to Lewis rats; another is syngrafts (from Lewis to Lewis rats serving as control. Renal tissues were collected 3, 7 and 14 days after transplantation. As many as 18 samples were analyzed by 2-D Electrophoresis and mass spectrometry (MALDI-TOF-TOF-MS. Eleven differentially expressed proteins were identified between groups. In conclusion, proteomic technology can detect renal tissue proteins associated with acute renal allograft rejection. Identification of these proteins as diagnostic markers for rejection in patients′ urine or sera may be useful and non-invasive, and these proteins might serve as novel therapeutic targets that also help to improve the understanding of mechanism of renal rejection.

Renal sympathetic denervation: MDCT evaluation of the renal arteries.

LENUS (Irish Health Repository)

Hutchinson, Barry D

2013-08-01

Percutaneous transluminal renal sympathetic denervation is a new treatment of refractory systemic hypertension. The purpose of this study was to assess the clinical utility of MDCT to evaluate the anatomic configuration of the renal arteries in the context of renal sympathetic denervation.

Patients with gout differ from healthy subjects in renal response to changes in serum uric acid.

Science.gov (United States)

Liu, Sha; Perez-Ruiz, Fernando; Miner, Jeffrey N

2017-03-01

Our objectives were to determine whether a change in serum uric acid (sUA) resulted in a corresponding change in the fractional excretion of uric acid (FEUA) and whether the renal response was different in patients with gout versus healthy subjects. FEUA was calculated from previously published studies and four new phase I studies in healthy subjects and/or patients with gout before and after treatment to lower or raise sUA. Treatments included xanthine oxidase inhibitors to lower sUA as well as infusion of uric acid and provision of a high-purine diet to raise sUA. Plots were created of FEUA versus sUA before and after treatment. For the phase I studies, percent change in FEUA per mg/dL change in sUA was calculated separately for healthy subjects and patients with gout, and compared using Student's t test. Analysis of previously published data and the new phase I clinical data indicates that changing sUA by a non-renal mechanism leads to a change in FEUA. The magnitude of change is greater in subjects with higher baseline FEUA versus patients with gout. Healthy subjects excrete more urate than do patients with gout at physiological urate-filtered load; this difference disappears when the urate-filtered load is decreased to ∼5000mg/24hours. These observations are consistent with a less saturated urate reabsorption system in patients with gout versus healthy subjects, resulting in elevated retention of uric acid. Further investigation could lead to the discovery of mechanisms responsible for the etiology of hyperuricemia/gout. Copyright © 2016 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

Relationship between renal cortex and parenchyma thickness and renal function: study with CT measurement

International Nuclear Information System (INIS)

Xu Yufeng; Tang Guangjian; Jiang Xuexiang

2006-01-01

Objective: To study the relationship between renal morphology and renal function, and to assess the value of CT as a criterion to grade renal function. Methods: Enhancement CT were performed in 89 patients with no local renal disease whose split renal glomerular filtration rates (GFR) were measured by renal dynamic imaging with 99 Tc m -DTPA. The 178 kidneys were divided into normal renal function, mild and severe renal impairment groups according to renal function. Differences between three groups respect to the mean thickness of renal cortex and parenchyma were assessed by ANOVA. Using Pearson's correlation test, the correlation between the renal cortex, parenchyma thicknesses and renal GFR were examined. The value of CT in predicting renal function was assessed by using ROC analysis. Results: The renal cortex thicknesses of normal renal function, mild and severe renal impairment groups were (5.9±1.1), (4.6± 1.1), and (3.3±1.0) mm respectively, and the renal parenchyma thicknesses were (26.3±4.2), (21.3±4.6), (16.2±4.6) mm. There were significant differences of renal cortex, parenchyma thicknesses between 3 groups (cortex F=54.78, P<0.01; parenehyma F=43.90, P<0.01). The thicknesses of renal cortex (r=0.752, P<0.01), parenchyma (r=0.738, P<0.01) had positive linear correlation with renal function. ROC analysis of the renal cortex thicknesses measured by CT in predicting mild and severe renal impairment showed that the Az was 0.860 and 0.905 respectively, whereas that of parenchyma was 0.868 and 0.884. Conclusion: The thicknesses of renal cortex, parenchyma measured by CT can reflect renal function. CT was a supplementary method to assess renal function. (authors)

Glomerular Filtration Rate Estimation in Renal and Non-Renal Solid Organ Transplantation

DEFF Research Database (Denmark)

Hornum, Mads; Feldt-Rasmussen, Bo

2017-01-01

Following transplantation (TX) of both renal and non-renal organs, a large proportion of patients have renal dysfunction. There are multiple causes for this. Chronic nephrotoxicity and high doses of calcineurin inhibitors are important factors. Preoperative and perioperative factors like...... or estimates of renal function in these patients, in order to accurately and safely dose immunosuppressive medication and perform and adjust the treatment and prophylaxis of renal dysfunction. This is a short overview and discussion of relevant studies and possible caveats of estimated glomerular filtration...... rate methods for use in renal and non-renal TX....

Superselective transcatheter renal arterial embolization for acute renal bleeding in patients with renal insufficiency: its clinical efficacy and safety

International Nuclear Information System (INIS)

Hu Tingyang; Zhou Bing; Yu Wenqiang; Luo Zuyan; Mao Yingmin; Chen Fanghong; Li Bo; Yuan Jianhua

2010-01-01

Objective: To discuss the clinical efficacy and complications of super selective renal arterial embolization in treating acute renal arterial bleeding in patients with renal insufficiency, and to evaluate the influence of the treatment on the renal function. Methods: During the period of January 2000 December 2009, super selective renal arterial embolization was performed in our institution for acute renal bleeding in 13 patients with renal insufficiency. The complete clinical and imaging materials of all patients were properly collected. The clinical effectiveness, the renal function, the extent of embolization and the complications were observed and the relationship between each other was analyzed. Results: The embolization procedure was successfully completed in all patients with a technical success rate of 100%. The mean embolized territory was 22% of a single kidney. Three days after the procedure, the hemoglobin level, hematocrit, blood pressure and heart rate were considerably improved in all patients. Compared to the corresponding preoperative data, all the differences were statistically significant (P 0.05), while the blood urea nitrogen was markedly decreased (P=0.011). Post embolization syndrome occurred in 5 patients and progressive aggravation of the renal function was observed in one patient, who had to receive hemodialysis finally. The embolized territory in patients occurring complications was larger than that in patients without occurring complications (U=1.500, P=0.006). Conclusion: Super selective renal arterial embolization is an effective and safe treatment for acute renal arterial bleeding in patients with renal insufficiency, the therapy will not significantly worsen the renal function. Appropriate and reasonable extent of embolization, as small as possible, is the key point for reducing the complications. (authors)

Secretory NaCl and volume flow in renal tubules.

Science.gov (United States)

Beyenbach, K W

1986-05-01

This review attempts to give a retrospective survey of the available evidence concerning the secretion of NaCl and fluid in renal tubules of the vertebrate kidney. In the absence of glomerular filtration, epithelial secretory mechanisms, which to this date have not been elucidated, are responsible for the renal excretion of NaCl and water in aglomerular fish. However, proximal tubules isolated from glomerular fish kidneys of the flounder, killifish, and the shark also have the capacity to secrete NaCl and fluid. In shark proximal tubules, fluid secretion appears to be driven via secondary active transport of Cl. In another marine vertebrate, the sea snake, secretion of Na (presumably NaCl) and fluid is observed in freshwater-adapted and water-loaded animals. Proximal tubules of mammals can be made to secrete NaCl in vitro together with secretion of aryl acids. An epithelial cell line derived from dog kidney exhibits secondary active secretion of Cl when stimulated with catecholamines. Tubular secretion of NaCl and fluid may serve a variety of renal functions, all of which are considered here. The occurrence of NaCl and fluid secretion in glomerular proximal tubules of teleosts, elasmobranchs, and reptiles and in mammalian renal tissue cultures suggests that the genetic potential for NaCl secretion is present in every vertebrate kidney.

Altered renal expression of angiotensin II receptors, renin receptor, and ACE-2 precede the development of renal fibrosis in aging rats.

Science.gov (United States)

Schulman, Ivonne Hernandez; Zhou, Ming-Sheng; Treuer, Adriana V; Chadipiralla, Kiranmai; Hare, Joshua M; Raij, Leopoldo

2010-01-01

The susceptibility to fibrosis and progression of renal disease is mitigated by inhibition of the renin-angiotensin system (RAS). We hypothesized that activation of the intrarenal RAS predisposes to renal fibrosis in aging. Intrarenal expression of angiotensin II type 1 (AT(1)R), type 2 (AT(2)R), and (pro)renin receptors, ACE and ACE-2, as well as pro- and antioxidant enzymes were measured in 3-month-old (young), 14-month-old (middle-aged), and 24-month-old (old) male Sprague-Dawley rats. Old rats manifested glomerulosclerosis and severe tubulointerstitial fibrosis with increased fibronectin and TGF-β expression (7-fold). AT(1)R /AT(2)R ratios were increased in middle-aged (cortical 1.6-fold, medullary 5-fold) and old rats (cortical 2-fold, medullary 4-fold). Similarly, (pro)renin receptor expression was increased in middle-aged (cortical 2-fold, medullary 3-fold) and old (cortical 5-fold, medullary 3-fold) rats. Cortical ACE was increased (+35%) in old rats, whereas ACE-2 was decreased (-50%) in middle-aged and old rats. NADPH oxidase activity was increased (2-fold), whereas antioxidant capacity and expression of the mitochondrial enzyme manganese superoxide dismutase (cortical -40%, medullary -53%) and medullary endothelial nitric oxide synthase (-48%) were decreased in old rats. Age-related intrarenal activation of the RAS preceded the development of severe renal fibrosis, suggesting that it contributes to the increased susceptibility to renal injury observed in the elderly. Copyright © 2010 S. Karger AG, Basel.

Detection of acute renal allograft rejection by analysis of Renal TissueProteomics in rat models of renal transplantation

International Nuclear Information System (INIS)

Dai, Y.; Lv, T.; Wang, K.; Li, D.; Huang, Y.; Liu, J.

2008-01-01

At present, the diagnosis of renal allograft rejection requires a renalbiopsy. Clinical management of renal transplant patients would be improved ifrapid, noninvasive and reliable biomarkers of rejection were available. Thisstudy is designed to determine whether such protein biomarkers can be foundin renal graft tissue proteomic approach. Orthotopic kidney transplantationswere performed using Fisher (F344) or Lewis rats as donors and Lewis rats asrecipients. Hence, there were two groups of renal transplant models: one isallograft (from F344 to Lewis rats); another is syngrafts (from Lewis toLewis rats) serving as control. Renal tissues were collected 3, 7 and 14 daysafter transplantation. As many 18 samples were analyzed by 2-DElectrophoresis and mass spectrometry (MALDI-TOF-TOF-MS). Elevendifferentially expressed proteins were identified between groups. Inconclusion, proteomic technology can detect renal tissue proteins associatedwith acute renal allograft rejection. Identification of these proteins asdiagnostic markers for rejection in patient's urine or sera may be useful andnon-invasive, and these proteins might serve as novel therapeutic targetsthat also help to improve the understanding of mechanisms of renal rejection.(author)

Anatomic Patterns of Renal Arterial Sympathetic Innervation: New Aspects for Renal Denervation.

Science.gov (United States)

Imnadze, Guram; Balzer, Stefan; Meyer, Baerbel; Neumann, Joerg; Krech, Rainer Horst; Thale, Joachim; Franz, Norbert; Warnecke, Henning; Awad, Khaled; Hayek, Salim S; Devireddy, Chandan

2016-12-01

Initial studies of catheter-based renal arterial sympathetic denervation to lower blood pressure in resistant hypertensive patients renewed interest in the sympathetic nervous system's role in the pathogenesis of hypertension. However, the SYMPLICITY HTN-3 study failed to meet its prespecified blood pressure lowering efficacy endpoint. To date, only a limited number of studies have described the microanatomy of renal nerves, of which, only two involve humans. Renal arteries were harvested from 15 cadavers from the Klinikum Osnabruck and Schuchtermann Klinik, Bad Rothenfelde. Each artery was divided longitudinally in equal thirds (proximal, middle, and distal), with each section then divided into equal superior, inferior, anterior, and posterior quadrants, which were then stained. Segments containing no renal nerves were given a score value = 0, 1-2 nerves with diameter 4 nerves or nerve diameter ≥600 µm a score = 3. A total of 22 renal arteries (9 right-sided, 13 left-sided) were suitable for examination. Overall, 691 sections of 5 mm thickness were prepared. Right renal arteries had significantly higher mean innervation grade (1.56 ± 0.85) compared to left renal arteries (1.09 ± 0.87) (P renal artery has significantly higher innervation scores than the left. The anterior and superior quadrants of the renal arteries scored higher in innervation than the posterior and inferior quadrants did. The distal third of the renal arteries are more innervated than the more proximal segments. These findings warrant further evaluation of the spatial innervation patterns of the renal artery in order to understand how it may enhance catheter-based renal arterial denervation procedural strategy and outcomes. The SYMPLICITY HTN-3 study dealt a blow to the idea of the catheter-based renal arterial sympathetic denervation. We investigated the location and patterns of periarterial renal nerves in cadaveric human renal arteries. To quantify the density of the

Estimation of rumen microbial protein production from urinary purine derivatives in zebu cattle and water buffalo

International Nuclear Information System (INIS)

Liang, J.B.; Pimpa, O.; Abdullah, N.; Jelan, Z.A.; Nolan, J.V.

1999-01-01

Two experiments were conducted in order to develop equations for predicting rumen microbial protein production for indigenous Kedah-Kelantan (KK) cattle and swamp buffaloes in Malaysia, using urinary purine derivatives (PD) excretion rates. Endogenous PD excretion rates determined by a fasting procedure for KK cattle and swamp buffalo were 275 and 370 μmol/kg W 0.75 /day, respectively. Urinary PD excretion rate per kg digestible organic matter intake (DOMI) for KK cattle was higher than that for swamp buffalo, reconfirming the earlier findings. Glomerular filtration rate, allantoin and uric acid tubular load and PD re-absorption rate for swamp buffalo were generally higher than those for KK cattle. However, due to the large variations among animals within species, these parameters were not significantly different between species. Nevertheless, the higher PD reabsorption in swamp buffalo provides support for the earlier postulation that the lower urinary PD excretion rate of swamp buffalo was due to their higher recycling of plasma PD as compared to KK cattle. Labelled 8- 14 C uric acid was used to estimate the ratio of renal to non-renal PD excretion. The recovery rates of the radioactive tracer via the renal route for both species were much lower than values reported previously for unlabelled PD for European cattle. (author)

[Nephrogenic diabetes insipidus].

Science.gov (United States)

Velásquez-Jones, Luis; Medeiros-Domingo, Mara

The anti-diuretic hormone arginine-vasopressin (AVP) is released from the pituitary and regulates water reabsorption in the principal cells of the kidney collecting duct. Binding of AVP to the arginine-vasopressin receptor type-2 in the basolateral membrane leads to translocation of aquaporin-2 water channels to the apical membrane of the principal cells of the collecting duct, inducing water permeability of the membrane. This results in water reabsorption in the collecting duct of the nephron following an osmotic gradient. Nephrogenic diabetes insipidus is caused by partial or complete renal resistance to the effects of AVP. Congenital nephrogenic diabetes insipidus is a disorder associated with mutations in either the AVPR2 or AQP2 gene, causing the inability of patients to concentrate their urine. Acquired nephrogenic diabetes insipidus can be caused by electrolyte imbalances (e.g., hypercalcemia, hypokalemia), renal/extra-renal diseases and drugs (e.g., lithium toxicity). This article reviews the causes, clinical manifestations, diagnosis and treatment of patients with nephrogenic diabetes insipidus. Based on more in-depth mechanistic understanding, new therapeutic strategies are current being explored. Copyright © 2014 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

Evaluation of renal uptake on 111InCl3 bone marrow scintigraphy in patients with aplastic anemia and myelodysplastic syndrome

International Nuclear Information System (INIS)

Koizumi, Mitsuru; Goto, Masafumi; Nomura, Toshiharu; Watari, Tsutomu; Saito, Kenji

1993-01-01

High renal uptake on bone marrow scan with indium-111 chloride is often shown in patients with bone marrow abnormality. We evaluated the renal uptake on bone marrow scan in 27 cases of aplastic anemia, 20 cases of myelodysplastic syndrome (MDS) and 10 cases of other diseases. The high renal uptake was observed in patients not only with aplastic anemia but also with MDS. The renal uptake correlated with blood transfusion units, unsaturated iron binding capacity (UIBC), blood pool imaging and bone marrow uptake. The renal uptake correlated with UIBC better than with the blood transfusion units. Following mechanism of the renal uptake is proposed that frequent blood transfusion makes low UIBC, and the low UIBC causes the failure to chelate indium with transferrin. The fast blood clearance of un-chelated indium via kidneys is followed. Hypoplastic bone marrow may also play an important role for the high renal uptake because all patients with the high renal uptake could not be explained by above mentioned mechanism. Caution should be paid to the scans with the high renal uptake because both aplastic anemia and MDS patients show the high renal uptake. (author)

The 64-MSCT study of relationship between renal corticomedullary differentiation, contrast between renal cortex and medulla, renal cortex and medulla CT peak value with the single renal function in hydronephrotic kidney

International Nuclear Information System (INIS)

Wang Yunhua; Hou Weiwei; Liu Ruihong; He Jianjun; Zhi Ke

2009-01-01

Objective: To study 64-MSCT perfusion imaging features about renal corticomedullary differentiation, contrast between renal cortex and medulla (CMC), renal cortex and medulla CT peak value in normal and hydronephrotic kidneys, and to explore the relationship between them and the unilateral renal function. Methods: Thirty-six patients with obstructive nephrohydrosis underwent 64-MSCT perfusion scanning. The split renal glomerular filtration rates (GFR) of their kidneys were measured by SPECT renal dynamic imaging. The 72 kidneys were divided into groups of normal renal function group, mild and severe renal impairment groups according to GFR. Renal corticomedullary differentiation on CT images was graded as clear, obscure, part clear. The CT intensity of cortex and medulla was measured in order to calculate contrast between renal cortex and medulla (CMC). Using Pearson correlation test, the correlation between them and renal GFR were examined. Results: (1) In the 24 kidneys of normal group, all kidneys showed clear CMD. In the 21 kidneys of mild renal impairment group, 14 kidneys showed clear CMD, 2 showed obscure CMD and 5 showed part clear of CMD. In the 27 kidneys of severe renal impairment group, 7 kidneys showed clear CMD, 5 showed obscure CMD and 15 showed part clear of CMD. (2)The CMC of normal group was 0.62 ± 0.20, while it was 0.52 ± 0.14 and 0.37 ± 0.11 for mild renal impairment group and severe renal impairment group CMC respectively. The CMC had positive linear correlation with GFR (r=0.536,P<0.05). (3) The renal cortex and medulla CT peak value of normal group were (133 ± 22) and (104 ± 16) HU; The renal cortex and medulla CT peak value of mild renal impairment group were (91 ± 29) and (76 ± 25) HU; The renal cortex and medulla CT peak value of severe renal impairment group were (68 ± 24) and (57 ± 21) HU(F=42.76 and 32.68,P<0.05). The renal cortex and medulla CT peak value had positive linear correlation with GFR (r=0.672 and 0.623, P<0

The intrarenal distribution of 125I-albumin in the syrian hamster

International Nuclear Information System (INIS)

Moeller, P.

1977-01-01

The intrarenal distribution of radioiodinated human serum albumin ( 125 RISA) after intravenous injection was studied in Syrian hamsters by scintillation counting and frozen section autoradiogrpahy. After 15, 30, and 60 min the virtual plasma albumin space in the renal cortex of the hamster represented 6.49, 7.13, and 8.06% respectively of the kidney tissue volume. From the cortex to the renal papilla the albumin space increased to about 30% of the tissue volume. In comparison to this the albumin space in the renal cortex of the rat was about 20%, and in the renal papilla about 33% (11). Frozen section autoradiography indicated that the distribution of radioalbumin in the renal cortex if the Syrian hamster is limited mainly to the kidney vessels, being especially noticeable in the glomerular capillaries. Toward the papilla increasingly greater (mainly extratubular) activity could be observed not only intravascularly but also interstitially. In the cortex of the rat kidney, on the other hand, radioactive albumin was accumulated (probably by filtration and reabsorption) predominantly in the proximal tubular epithelium. Within 30 min the kidneys of the rat excreted more than 10 times as much 125 I than the hamster kidneys. These results (substantially less cortical accumulation and urinary excretion of radioalbumin in the Syrian hamster) indicate that, in contrast to the rat, obviously much less albumin is filtered (and then accumulated by proximal reabsorption) by the Syrian hamster glomeruli. This suggests that the Syrian hamster kidney is more suitable than the rat kidney for determining the interstitial, cortical, albumin space. (orig./AJ) [de

Multiple Renal Artery Pseudoaneurysms in Patients Undergoing Renal Artery Embolization Following Partial Nephrectomy: Correlation with RENAL Nephrometry Scores

International Nuclear Information System (INIS)

Gupta, Nakul; Patel, Anish; Ensor, Joe; Ahrar, Kamran; Ahrar, Judy; Tam, Alda; Odisio, Bruno; Huang, Stephen; Murthy, Ravi; Mahvash, Armeen; Avritscher, Rony; McRae, Stephen; Sabir, Sharjeel; Wallace, Michael; Matin, Surena; Gupta, Sanjay

2017-01-01

PurposeTo describe the incidence of multiple renal artery pseudoaneurysms (PSA) in patients referred for renal artery embolization following partial nephrectomy and to study its relationship to RENAL nephrometry scores.Materials and MethodsThe medical records of 25 patients referred for renal artery embolization after partial nephrectomy were retrospectively reviewed for the following parameters: size and number of tumors, RENAL nephrometry scores, angiographic abnormalities, technical and clinical outcomes, and estimated glomerular filtration rates (eGFRs) after embolization.ResultsTwenty-four patients had primary renal tumors, while 1 patient had a pancreatic tumor invading the kidney. Multiple tumors were resected in 4 patients. Most patients (92 %) were symptomatic, presenting with gross hematuria, flank pain, or both. Angiography revealed PSA with (n = 5) or without (n = 20) AV fistulae. Sixteen patients (64 %) had multiple PSA involving multiple renal vessels. Higher RENAL nephrometry scores were associated with an increasing likelihood of multiple PSA. Multiple vessels were embolized in 14 patients (56 %). Clinical success was achieved after one (n = 22) or two (n = 3) embolization sessions in all patients. Post-embolization eGFR values at different time points after embolization were not significantly different from the post-operative eGFR.ConclusionA majority of patients requiring renal artery embolization following partial nephrectomy have multiple pseudoaneurysms, often requiring selective embolization of multiple vessels. Higher RENAL nephrometry score is associated with an increasing likelihood of multiple pseudoaneurysms. We found transarterial embolization to be a safe and effective treatment option with no long-term adverse effect on renal function in all but one patient with a solitary kidney.

Multiple Renal Artery Pseudoaneurysms in Patients Undergoing Renal Artery Embolization Following Partial Nephrectomy: Correlation with RENAL Nephrometry Scores

Energy Technology Data Exchange (ETDEWEB)

Gupta, Nakul [Houston Methodist Hospital (United States); Patel, Anish [The University of Texas Southwestern Medical Center (United States); Ensor, Joe [Houston Methodist Research Institute, The Houston Methodist Cancer Center (United States); Ahrar, Kamran; Ahrar, Judy; Tam, Alda; Odisio, Bruno; Huang, Stephen; Murthy, Ravi; Mahvash, Armeen; Avritscher, Rony; McRae, Stephen; Sabir, Sharjeel; Wallace, Michael [The University of Texas MD Anderson Cancer Center, Department of Interventional Radiology (United States); Matin, Surena [The University of Texas MD Anderson Cancer Center, Department of Urology (United States); Gupta, Sanjay, E-mail: sgupta@mdanderson.org [The University of Texas MD Anderson Cancer Center, Department of Interventional Radiology (United States)

2017-02-15

PurposeTo describe the incidence of multiple renal artery pseudoaneurysms (PSA) in patients referred for renal artery embolization following partial nephrectomy and to study its relationship to RENAL nephrometry scores.Materials and MethodsThe medical records of 25 patients referred for renal artery embolization after partial nephrectomy were retrospectively reviewed for the following parameters: size and number of tumors, RENAL nephrometry scores, angiographic abnormalities, technical and clinical outcomes, and estimated glomerular filtration rates (eGFRs) after embolization.ResultsTwenty-four patients had primary renal tumors, while 1 patient had a pancreatic tumor invading the kidney. Multiple tumors were resected in 4 patients. Most patients (92 %) were symptomatic, presenting with gross hematuria, flank pain, or both. Angiography revealed PSA with (n = 5) or without (n = 20) AV fistulae. Sixteen patients (64 %) had multiple PSA involving multiple renal vessels. Higher RENAL nephrometry scores were associated with an increasing likelihood of multiple PSA. Multiple vessels were embolized in 14 patients (56 %). Clinical success was achieved after one (n = 22) or two (n = 3) embolization sessions in all patients. Post-embolization eGFR values at different time points after embolization were not significantly different from the post-operative eGFR.ConclusionA majority of patients requiring renal artery embolization following partial nephrectomy have multiple pseudoaneurysms, often requiring selective embolization of multiple vessels. Higher RENAL nephrometry score is associated with an increasing likelihood of multiple pseudoaneurysms. We found transarterial embolization to be a safe and effective treatment option with no long-term adverse effect on renal function in all but one patient with a solitary kidney.

Active lithium transport by rat renal proximal tubule: a micropuncture study

DEFF Research Database (Denmark)

Leyssac, P P; Frederiksen, O; Holstein-Rathlou, N H

1994-01-01

We tested the hypothesis that proximal tubular Li+ reabsorption is due to passive transport. Clearances of [14C]inulin (CIn) and Li+ (CLi), proximal transepithelial electrical potential difference (PD), and tubular fluid-to-plasma Li+ concentration ratios [(TF/P)Li] were measured in anesthetized ...

The renal quantitative scintillation camera study for determination of renal function

International Nuclear Information System (INIS)

Thompson, I.M. Jr.; Boineau, F.G.; Evans, B.B.; Schlegel, J.U.

1983-01-01

The renal quantitative scintillation camera study assesses glomerular filtration rate and effective renal plasma flow based upon renal uptake of 99mtechnetium-iron ascorbate and 131iodine-hippuran, respectively. The method was compared to inulin, para-aminohippuric acid and creatinine clearance studies in 7 normal subjects and 9 patients with various degrees of reduced renal function. The reproducibility of the technique was determined in 15 randomly selected pediatric patients. The values of glomerular filtration rate and effective renal plasma flow were not significantly different from those of inulin and para-aminohippuric acid studies. The reproducibility of the technique was comparable to that of inulin and para-aminohippuric acid studies. Patient acceptance of the technique is excellent and the cost is minimal. Renal morphology and excretory dynamics also are demonstrated. The technique is advocated as a clinical measure of renal function

Inhibiting aerobic glycolysis suppresses renal interstitial fibroblast activation and renal fibrosis.

Science.gov (United States)

Ding, Hao; Jiang, Lei; Xu, Jing; Bai, Feng; Zhou, Yang; Yuan, Qi; Luo, Jing; Zen, Ke; Yang, Junwei

2017-09-01

Chronic kidney diseases generally lead to renal fibrosis. Despite great progress having been made in identifying molecular mediators of fibrosis, the mechanism that governs renal fibrosis remains unclear, and so far no effective therapeutic antifibrosis strategy is available. Here we demonstrated that a switch of metabolism from oxidative phosphorylation to aerobic glycolysis (Warburg effect) in renal fibroblasts was the primary feature of fibroblast activation during renal fibrosis and that suppressing renal fibroblast aerobic glycolysis could significantly reduce renal fibrosis. Both gene and protein assay showed that the expression of glycolysis enzymes was upregulated in mouse kidneys with unilateral ureter obstruction (UUO) surgery or in transforming growth factor-β1 (TGF-β1)-treated renal interstitial fibroblasts. Aerobic glycolysis flux, indicated by glucose uptake and lactate production, was increased in mouse kidney with UUO nephropathy or TGF-β1-treated renal interstitial fibroblasts and positively correlated with fibrosis process. In line with this, we found that increasing aerobic glycolysis can remarkably induce myofibroblast activation while aerobic glycolysis inhibitors shikonin and 2-deoxyglucose attenuate UUO-induced mouse renal fibrosis and TGF-β1-stimulated myofibroblast activation. Furthermore, mechanistic study indicated that shikonin inhibits renal aerobic glycolysis via reducing phosphorylation of pyruvate kinase type M2, a rate-limiting glycolytic enzyme associated with cell reliance on aerobic glycolysis. In conclusion, our findings demonstrate the critical role of aerobic glycolysis in renal fibrosis and support treatment with aerobic glycolysis inhibitors as a potential antifibrotic strategy. Copyright © 2017 the American Physiological Society.

RENAL CRYOABLATION

Directory of Open Access Journals (Sweden)

A. V. Govorov

2012-01-01

Full Text Available Renal cryoablation is an alternative minimally-invasive method of treatment for localized renal cell carcinoma. The main advantages of this methodology include visualization of the tumor and the forming of "ice ball" in real time, fewer complications compared with other methods of treatment of renal cell carcinoma, as well as the possibility of conducting cryotherapy in patients with concomitant pathology. Compared with other ablative technologies cryoablation has a low rate of repeat sessions and good intermediate oncological results. The studies of long-term oncological and functional results of renal cryoablation are presently under way.

Renal artery pulsatility index and renal volume: Normal fetuses versus growth-retarded fetuses

International Nuclear Information System (INIS)

Lee, Kyung Soon; Woo, Bock Hi

2001-01-01

To evaluate the blood flow velocity waveform of the renal artery and renal volume of growth-retarded fetuses and to compare them with those of normal fetuses. Pulsatility index of the renal artery and renal volume measured by three-dimensional ultrasonography were obtained from seventy eight normal fetuses at the gestational age from twenty five to thirty nine weeks and eighteen intrauterine growth retarded fetuses whose weight was below ten percentile at birth. We studied changes of the pulsatility index of the renal artery and renal volume according to the gestational age and compared with those of growth-retarded fetuses. Pulsatility index (PI) of the fetal renal artery decreased throughout the gestational period (r=0.703, p<0.0001). In growth-retarded fetuses, despite of abnormal doppler velocity waveform of the middle cerebral artery, which was showing fetal hypoxia, the renal PI was not increased significantly. The fetal renal volume increased throughout the gestational period (r=0.834, p<0.0001) whereas in growth-retarded fetuses, all renal volume was below fifth percentile of normal fetuses. In growth-retarded fetuses, fetal renal volume was decreased significantly without change of the renal vascular flow. Therefore, the fetal renal volume measured by three-dimensional ultrasonography may be a helpful parameter in the diagnosis of growth-retarded fetuses.

Renal artery pulsatility index and renal volume: Normal fetuses versus growth-retarded fetuses

Energy Technology Data Exchange (ETDEWEB)

Lee, Kyung Soon; Woo, Bock Hi [Ewha Womans University College of Medicine, Seoul (Korea, Republic of)

2001-06-15

To evaluate the blood flow velocity waveform of the renal artery and renal volume of growth-retarded fetuses and to compare them with those of normal fetuses. Pulsatility index of the renal artery and renal volume measured by three-dimensional ultrasonography were obtained from seventy eight normal fetuses at the gestational age from twenty five to thirty nine weeks and eighteen intrauterine growth retarded fetuses whose weight was below ten percentile at birth. We studied changes of the pulsatility index of the renal artery and renal volume according to the gestational age and compared with those of growth-retarded fetuses. Pulsatility index (PI) of the fetal renal artery decreased throughout the gestational period (r=0.703, p<0.0001). In growth-retarded fetuses, despite of abnormal doppler velocity waveform of the middle cerebral artery, which was showing fetal hypoxia, the renal PI was not increased significantly. The fetal renal volume increased throughout the gestational period (r=0.834, p<0.0001) whereas in growth-retarded fetuses, all renal volume was below fifth percentile of normal fetuses. In growth-retarded fetuses, fetal renal volume was decreased significantly without change of the renal vascular flow. Therefore, the fetal renal volume measured by three-dimensional ultrasonography may be a helpful parameter in the diagnosis of growth-retarded fetuses.

Obesity and renal hemodynamics

NARCIS (Netherlands)

Bosma, R. J.; Krikken, J. A.; van der Heide, J. J. Homan; de Jong, P. E.; Navis, G. J.

2006-01-01

Obesity is a risk factor for renal damage in native kidney disease and in renal transplant recipients. Obesity is associated with several renal risk factors such as hypertension and diabetes that may convey renal risk, but obesity is also associated with an unfavorable renal hemodynamic profile

Does the presence of accessory renal arteries affect the efficacy of renal denervation?

Science.gov (United States)

Id, Dani; Kaltenbach, Benjamin; Bertog, Stefan C; Hornung, Marius; Hofmann, Ilona; Vaskelyte, Laura; Sievert, Horst

2013-10-01

This study sought to assess the efficacy of catheter-based renal sympathetic denervation in patients with accessory renal arteries and to compare the blood pressure (BP)-lowering effect with that observed in patients with bilateral single renal arteries after renal denervation. Catheter-based renal sympathetic denervation causes significant BP reductions in patients with resistant hypertension. Seventy-four patients were included in this study. Patients were assigned to 2 main groups: a bilateral single renal arteries group I (n = 54) and an accessory renal arteries group II (n = 20). Group II consisted of 9 patients whose accessory renal arteries were all denervated (group IIa), and 11 patients whose accessory renal arteries were not, or only incompletely, denervated (group IIb). The primary endpoint was the change in office systolic BP after 6 months. The procedure was successful in all patients. Group I: mean BP at baseline was 166.2/89.4 ± 20.5/14.6 mm Hg and decreased by -16.6 (p renal denervation in patients with accessory renal arteries is less pronounced than in patients with bilateral single renal arteries. Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Radiopharmaceuticals for renal studies

International Nuclear Information System (INIS)

Verdera, Silvia

1994-01-01

Between the diagnostic techniques using radiopharmaceuticals in nuclear medicine it find renal studies.A brief description about renal glomerular filtration(GFR) and reliability renal plasma flux (ERPF),renal blood flux measurement agents (RBF),renal scintillation agents and radiation dose estimates by organ physiology was given in this study.tabs

Glomerular Filtration Rate Estimation in Renal and Non-Renal Solid Organ Transplantation

DEFF Research Database (Denmark)

Hornum, Mads; Feldt-Rasmussen, Bo

2017-01-01

Following transplantation (TX) of both renal and non-renal organs, a large proportion of patients have renal dysfunction. There are multiple causes for this. Chronic nephrotoxicity and high doses of calcineurin inhibitors are important factors. Preoperative and perioperative factors like hyperten......Following transplantation (TX) of both renal and non-renal organs, a large proportion of patients have renal dysfunction. There are multiple causes for this. Chronic nephrotoxicity and high doses of calcineurin inhibitors are important factors. Preoperative and perioperative factors like...... hypertension, hypotension, drugs and infections may play a causative role as well. Organ-specific causes include hepatorenal syndrome, cirrhosis, low cardiac function, low respiratory function and diabetes developed both before and after TX. It is important to be able to perform precise and valid measurements...... rate methods for use in renal and non-renal TX....

Treatment of non-neoplastic renal hemorrhage with segmental embolization of renal artery

International Nuclear Information System (INIS)

Zhu Bing

2007-01-01

Objective: To explore the value of segmental embolization of renal artery in dealing with non- neoplastic renal hemorrhage. Methods: Four cases of non-neoplastic hemorrhage, including 2 with bleeding after renal acupuncture biopsy, 2 with bleeding after nephrolithotomy and 1 with congenital renal arteriovenous malformation, were treated with superselective segmental embolization of renal artery. 2 were embolized with coil, 1 with alcohol plus coil and 1 with PVA parcels. Results: Hematuria disappeared in 1-3 days. There was no recurrence in 7-45 months follow up and no complications induced by embolization. Conclusion: It is a safe and reliable therapy to treat non-neoplastic renal hemorrhage with segmental embolization of renal artery. (authors)

Pharmacokinetics, pharmacodynamics, and tolerability of verinurad, a selective uric acid reabsorption inhibitor, in healthy adult male subjects

Directory of Open Access Journals (Sweden)

Shen Z

2017-07-01

Full Text Available Zancong Shen,1 Michael Gillen,2 Jeffrey N Miner,1 Gail Bucci,1 David M Wilson,1 Jesse W Hall1 1Ardea Biosciences, Inc., San Diego, CA, 2AstraZeneca, Gaithersburg, MD, USA Purpose: Verinurad (RDEA3170 is a selective uric acid reabsorption inhibitor in clinical development for the treatment of gout and asymptomatic hyperuricemia. The aim of this study was to evaluate the pharmacokinetics, pharmacodynamics, and tolerability of verinurad in healthy adult males.Subjects and methods: This was a Phase I, randomized, double-blind, placebo-controlled, single and multiple ascending dose study. Panels of eight male subjects received a single oral dose of verinurad or placebo in either a fasted or fed state; panels of 10–12 male subjects received ascending doses of once-daily verinurad or placebo in a fasted state for 10 days. Serial blood and urine samples were assayed for verinurad and uric acid. Safety was assessed by adverse event (AE reports, laboratory tests, vital signs, and electrocardiograms (ECGs.Results: A total of 81 adult males completed the study. Following single doses of verinurad, maximum observed plasma concentration (Cmax and area under the plasma concentration–time curve (AUC increased in a dose-proportional manner; Cmax occurred at 0.5–0.75 hours and 1.25 hours in the fasted and fed states, respectively. Food decreased AUC by 23% and Cmax by 37%-53%. There was a modest accumulation of verinurad following multiple daily doses. Verinurad reduced serum urate levels by up to 62% (40 mg, single dose and 61% (10 mg, multiple dose. The increase in urinary excretion of uric acid was greatest in the first 6 hours after dosing and was still evident ≥24 hours for verinurad doses ≥2 mg. Verinurad was well tolerated at all doses. No serious AEs, severe AEs, discontinuations due to AEs, or clinically significant laboratory or ECG abnormalities were reported.Conclusion: Single and multiple doses of verinurad were well tolerated

Scleroderma renal crisis and ovarian hyperstimulation syndrome related to the use of clomiphene in a patient with scleroderma.

Science.gov (United States)

Kobak, Senol; Hacivelioglu, Servet; Gungor, Selen

2014-01-01

This paper presented a 28-year-old female with systemic sclerosis who developed scleroderma renal crisis and ovarian hyperstimulation syndrome following clomiphene administration. Urgent therapy including angiotensin-converting enzyme (ACE) inhibitors and supportive care resulted in regression and eventually resolution of all the clinical and laboratory symptoms. Although scleroderma renal crisis is a fatal complication of high-dose corticosteroids, rarely is this seen with the use of ACE inhibitors. This case report aimed to investigate the potential capacity of the selective oestrogen receptor modulator clomiphene to induce scleroderma renal crisis as well as corticosteroids. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Bilateral renal artery variation

OpenAIRE

Üçerler, Hülya; Üzüm, Yusuf; İkiz, Z. Aslı Aktan

2014-01-01

Each kidney is supplied by a single renal artery, although renal artery variations are common. Variations of the renal arteryhave become important with the increasing number of renal transplantations. Numerous studies describe variations in renalartery anatomy. Especially the left renal artery is among the most critical arterial variations, because it is the referred side forresecting the donor kidney. During routine dissection in a formalin fixed male cadaver, we have found a bilateral renal...

[Aortic dissection spread to the renal arteries: role of renal volumetry after angioplasty].

Science.gov (United States)

Vautrin, E; Thony, F; Chavanon, O; Hannachi, I; Barone-Rochette, G; Pierre, H; Baguet, J-P

2012-06-01

Type A or B aortic dissection can extend to renal arteries, causing a renal ischemia which treatment is usually endovascular. The aim of our study is to show the interest of the renal volumetry in the follow-up of these patients. Twenty-two patients (16 men, mean age 63.4±11.8years, BMI 25.2±3.4kg/m(2)) with a type A or B aortic dissection spread to one or to both renal arteries and followed at Grenoble university hospital were consecutively included. All patients underwent renal angiography with aorto-renal pressure gradients measurements and follow-up by renal volumetry (scanner Siemens(®)). A renal ischemia was defined by a decrease of 20% or more of the volumetry. Sixteen patients (73%) were hypertensive before the aortic dissection among which ten (62%) were treated. Eight patients (36%) have a significant renal pressure gradient among which five (62%) underwent renal endovascular therapy. The renal volumetry of these five patients remained unchanged while six of 17 patients (36%) without angioplasty have a decreasing volumetry. Renal volumetry appeared an effective and attractive option for the follow-up of the patients with aortic dissection spread to the renal arteries. These results should be taken into account to put the indication of an endovascular treatment. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

BILATERAL DUPLICATION OF RENAL ARTERIES

OpenAIRE

Prajkta A Thete; Mehera Bhoir; M.V.Ambiye

2014-01-01

Routine dissection of a male cadaver revealed the presence of bilateral double renal arteries. On the right side the accessory renal artery originated from the abdominal aorta just above the main renal artery. On the left side the accessory renal artery originated from the abdominal aorta about 1 cm above the main renal artery. Knowledge of the variations of renal vascular anatomy has importance in exploration and treatment of renal trauma, renal transplantation, renal artery embolization, su...

Oxidative stress and hemoglobin-cholesterol adduct in renal patients with different LDL phenotypes.

Science.gov (United States)

Miljkovic, Milica; Kotur-Stevuljevic, Jelena; Stefanovic, Aleksandra; Zeljkovic, Aleksandra; Vekic, Jelena; Gojkovic, Tamara; Bogavac-Stanojevic, Natasa; Nikolic, Milan; Simic-Ogrizovic, Sanja; Spasojevic-Kalimanovska, Vesna; Jelic-Ivanovic, Zorana

2016-10-01

Unfavorable lipid profile is a major risk factor for cardiovascular disease in renal pathology. In this study, we compared chronic renal patients and healthy controls with different LDL phenotypes (A or B) in respect of various biochemical parameters related to cardiovascular disease. Oxidative stress and anti-oxidative defense parameters [thiobarbituric acid-reacting substances (TBARS), total oxidative status (TOS), total anti-oxidative status (TAS), total protein sulfhydryl (-SH) groups], as well as red blood cell cholesterol distribution were assessed in 40 renal patients and 40 control subjects by standardized assays. LDL particle diameters were determined by polyacrylamide gradient gel electrophoresis. LDL particles are subdivided according to their size into large LDL A phenotype (diameter >25.5 nm) and small LDL B phenotype (diameter ≤25.5 nm). Renal patients with LDL A phenotype had increased oxidative stress (TOS: p LDL phenotype. A notable decrease in hemoglobin-cholesterol adduct was detected in patients with LDL A phenotype (p LDL B phenotype (p LDL B phenotype was characterized with increased TBARS (p LDL A phenotype in control group. Increased oxidative stress, decreased anti-oxidative defense followed with unfavorable changes in hemoglobin-cholesterol binding capacity, could have important influence on cardiovascular disease risk in renal patients regardless of LDL phenotype.

Computed tomography of renal cell carcinoma in patients with terminal renal impairment

International Nuclear Information System (INIS)

Ferda, Jiri; Hora, Milan; Hes, Ondrej; Reischig, Tomas; Kreuzberg, Boris; Mirka, Hynek; Ferdova, Eva; Ohlidalova, Kristyna; Baxa, Jan; Urge, Tomas

2007-01-01

Purpose: An increased incidence of renal tumors has been observed in patients with end-stage-renal-disease (ESRD). The very strong association with acquired renal cystic disease (ACRD) and increased incidence of the renal tumors (conventional renal cell carcinoma (CRCC), papillary renal cell carcinoma (PRCC) or papillary renal cell adenoma (PRCA)) was reported. This study discusses the role of computed tomography (CT) in detecting renal tumors in patients with renal impairment: pre-dialysis, those receiving dialysis or with renal allograft transplants. Materials and methods: Ten patients (nine male, one female) with renal cell tumors were enrolled into a retrospective study; two were new dialysis patients, three on long-term dialysis, and five were renal transplant recipients with history of dialysis. All patients underwent helical CT, a total of 11 procedures were performed. Sixteen-row detector system was used five times, and a 64-row detector system for the six examinations. All patients underwent nephrectomy of kidney with suspected tumor, 15 nephrectomies were performed, and 1 kidney was assessed during autopsy. CT findings were compared with macroscopic and microscopic assessments of the kidney specimen in 16 cases. Results: Very advanced renal parenchyma atrophy with small cysts corresponding to ESRD was found in nine patients, chronic pyelonephritis in remained one. A spontaneously ruptured tumor was detected incidentally in one case, patient died 2 years later. In the present study, 6.25% (1/16) were multiple PRCA, 12.5% (2/16) were solitary PRCC, 12.5% tumors (2/16) were solitary conventional renal cell carcinomas (CRCC's), 12.5% tumors (2/16) were multiple conventional renal cell carcinomas (CRCC's), 25% (4/16) were CRCC's combined with multiple papillary renal cell carcinomas with adenomas (PRCC's and PRCA's), and 25% (4/16) of the tumors were multiple PRCC's combined with PRCA's without coexisting CRCC's. Bilateral renal tumors were found in our study

Traumatic renal infarction

International Nuclear Information System (INIS)

Yashiro, Naobumi; Ohtomo, Kuni; Kokubo, Takashi; Itai, Yuji; Iio, Masahiro

1986-01-01

Four cases of traumatic renal artery occlusion were described and illustrated. In two cases, direct blows to the abdomen compressed the renal artery against the vertebral column. Clinically, they were severely injured with macroscopic hematuria. Aortograms showed abrupt truncation of renal arteries. In the other two, rapid deceleration caused sudden displacement of the kidney producing an intimal tear with resultant thrombosis. Although they showed little injury without macrohematuria, aortograms revealed tapered occlusion of renal arteries. One of them developed hypertension. ''Rim sign'' of post-contrast CT and hypertension resulted from traumatic renal artery occlusion were reviewed. (author)

Imaging chronic renal disease and renal transplant in children

International Nuclear Information System (INIS)

Carmichael, Jim; Easty, Marina

2010-01-01

At Great Ormond Street Hospital we have the highest number of paediatric renal transplant patients in Europe, taking cases from across the United Kingdom and abroad. Our caseload includes many children with rare complicating medical problems and chronic renal failure related morbidity. This review aims to provide an overview of our experience of imaging children with chronic renal failure and transplants. (orig.)

Renal sodium-glucose cotransporter inhibition in the management of type 2 diabetes mellitus

Science.gov (United States)

Abdul-Ghani, Muhammad A.; Norton, Luke

2015-01-01

Hyperglycemia is the primary factor responsible for the microvascular, and to a lesser extent macrovascular, complications of diabetes. Despite this well-established relationship, approximately half of all type 2 diabetic patients in the US have a hemoglobin A1c (HbA1c) ≥7.0%. This is associated in part with the side effects, i.e., weight gain and hypoglycemia, of currently available antidiabetic agents and in part with the failure to utilize medications that reverse the basic pathophysiological defects present in patients with type 2 diabetes. The kidney has been shown to play a central role in the development of hyperglycemia by excessive production of glucose throughout the sleeping hours and enhanced reabsorption of filtered glucose by the renal tubules secondary to an increase in the threshold at which glucose spills into the urine. Recently, a new class of antidiabetic agents, the sodium-glucose cotransporter 2 (SGLT2) inhibitors, has been developed and approved for the treatment of patients with type 2 diabetes. In this review, we examine their mechanism of action, efficacy, safety, and place in the therapeutic armamentarium. Since the SGLT2 inhibitors have a unique mode of action that differs from all other oral and injectable antidiabetic agents, they can be used at all stages of the disease and in combination with all other antidiabetic medications. PMID:26354881

Radionuclide evaluation of renal transplants

International Nuclear Information System (INIS)

Yang Hong; Zhao Deshan

2000-01-01

Radionuclide renal imaging and plasma clearance methods can quickly quantitate renal blood flow and function in renal transplants. They can diagnose acute tubular necrosis and rejection, renal scar, surgical complications such as urine leaks, obstruction and renal artery stenosis after renal transplants. At the same time they can assess the therapy effect of renal transplant complications and can also predict renal transplant survival from early post-operative function studies

Rapid redistribution and inhibition of renal sodium transporters during acute pressure natriuresis

DEFF Research Database (Denmark)

Zhang, Y; Mircheff, A K; Hensley, C B

1996-01-01

and basolateral Na+ pumps to internal membranes. Arterial pressure was increased 50 mmHg by constricting various arteries. We also tested whether transporter internalization occurred when PT Na+ reabsorption was inhibited with the carbonic anhydrase inhibitor benzolamide. Five minutes after initiating either...

[Prescribing diuretics: what a practitioner needs to know].

Science.gov (United States)

Richard, C; Saudan, P; Ernandez, T

2015-02-25

Diuretics are among the most frequently prescribed drugs. Most of them act by inhibiting sodium reabsorption in various nephron segments. By understanding their pharmacological characteristics, it is possible to adapt the type of diuretic to different clinical situations. Practical aspects of their use, including in heart failure, cirrhosis, the nephrotic syndrome and renal failure, are discussed.

Renal Replacement Therapy Modality in the ICU and Renal Recovery at Hospital Discharge.

Science.gov (United States)

Bonnassieux, Martin; Duclos, Antoine; Schneider, Antoine G; Schmidt, Aurélie; Bénard, Stève; Cancalon, Charlotte; Joannes-Boyau, Olivier; Ichai, Carole; Constantin, Jean-Michel; Lefrant, Jean-Yves; Kellum, John A; Rimmelé, Thomas

2018-02-01

Acute kidney injury requiring renal replacement therapy is a major concern in ICUs. Initial renal replacement therapy modality, continuous renal replacement therapy or intermittent hemodialysis, may impact renal recovery. The aim of this study was to assess the influence of initial renal replacement therapy modality on renal recovery at hospital discharge. Retrospective cohort study of all ICU stays from January 1, 2010, to December 31, 2013, with a "renal replacement therapy for acute kidney injury" code using the French hospital discharge database. Two hundred ninety-one ICUs in France. A total of 1,031,120 stays: 58,635 with renal replacement therapy for acute kidney injury and 25,750 included in the main analysis. None. PPatients alive at hospital discharge were grouped according to initial modality (continuous renal replacement therapy or intermittent hemodialysis) and included in the main analysis to identify predictors of renal recovery. Renal recovery was defined as greater than 3 days without renal replacement therapy before hospital discharge. The main analysis was a hierarchical logistic regression analysis including patient demographics, comorbidities, and severity variables, as well as center characteristics. Three sensitivity analyses were performed. Overall mortality was 56.1%, and overall renal recovery was 86.2%. Intermittent hemodialysis was associated with a lower likelihood of recovery at hospital discharge; odds ratio, 0.910 (95% CI, 0.834-0.992) p value equals to 0.0327. Results were consistent across all sensitivity analyses with odds/hazards ratios ranging from 0.883 to 0.958. In this large retrospective study, intermittent hemodialysis as an initial modality was associated with lower renal recovery at hospital discharge among patients with acute kidney injury, although the difference seems somewhat clinically limited.

Technical aspects of renal denervation in end-stage renal disease patients with challenging anatomy.

Science.gov (United States)

Spinelli, Alessio; Da Ros, Valerio; Morosetti, Daniele; Onofrio, Silvia D; Rovella, Valentina; Di Daniele, Nicola; Simonetti, Giovanni

2014-01-01

We describe our preliminary experience with percutaneous renal denervation in end-stage renal disease patients with resistant hypertension and challenging anatomy, in terms of the feasibility, safety, and efficacy of this procedure. Four patients with end-stage renal disease patients with resistant hypertension (mean hemodialysis time, 2.3 years) who had been taking at least four antihypertensive medications underwent percutaneous renal denervation. Renal artery eligibility included the absence of prior renal artery interventions, vessel stenosis renal denervation is a feasible approach for end-stage renal disease patients with resistant hypertension with encouraging short-term preliminary results in terms of procedural efficacy and safety.

Renal rescue of dopamine D2 receptor function reverses renal injury and high blood pressure

Science.gov (United States)

Konkalmatt, Prasad R.; Asico, Laureano D.; Zhang, Yanrong; Yang, Yu; Drachenberg, Cinthia; Zheng, Xiaoxu; Han, Fei; Jose, Pedro A.; Armando, Ines

2016-01-01

Dopamine D2 receptor (DRD2) deficiency increases renal inflammation and blood pressure in mice. We show here that long-term renal-selective silencing of Drd2 using siRNA increases renal expression of proinflammatory and profibrotic factors and blood pressure in mice. To determine the effects of renal-selective rescue of Drd2 expression in mice, the renal expression of DRD2 was first silenced using siRNA and 14 days later rescued by retrograde renal infusion of adeno-associated virus (AAV) vector with DRD2. Renal Drd2 siRNA treatment decreased the renal expression of DRD2 protein by 55%, and DRD2 AAV treatment increased the renal expression of DRD2 protein by 7.5- to 10-fold. Renal-selective DRD2 rescue reduced the expression of proinflammatory factors and kidney injury, preserved renal function, and normalized systolic and diastolic blood pressure. These results demonstrate that the deleterious effects of renal-selective Drd2 silencing on renal function and blood pressure were rescued by renal-selective overexpression of DRD2. Moreover, the deleterious effects of 45-minute bilateral ischemia/reperfusion on renal function and blood pressure in mice were ameliorated by a renal-selective increase in DRD2 expression by the retrograde ureteral infusion of DRD2 AAV immediately after the induction of ischemia/reperfusion injury. Thus, 14 days after ischemia/reperfusion injury, the renal expression of profibrotic factors, serum creatinine, and blood pressure were lower in mice infused with DRD2 AAV than in those infused with control AAV. These results indicate an important role of renal DRD2 in limiting renal injury and preserving normal renal function and blood pressure. PMID:27358912

Evaluation of kidney repair capacity using 99mTc-DMSA in ischemia/reperfusion injury models.

Science.gov (United States)

Kwak, Wonjung; Jang, Hee-Seong; Belay, Takele; Kim, Jinu; Ha, Yeong Su; Lee, Sang Woo; Ahn, Byeong-Cheol; Lee, Jaetae; Park, Kwon Moo; Yoo, Jeongsoo

2011-03-04

Quantitative (99m)Tc-DMSA renal uptake was studied in different renal ischemia/reperfusion (I/R) mice models for the assessment of renal repair capacity. Mice models of nephrectomy, uni- and bi-lateral I/R together with sham-operated mice were established. At 1h, 1d, 4d, 1, 2 and 3 wk after I/R, (99m)Tc-DMSA (27.7 ± 1.3 MBq) was injected via tail vein and after 3h post-injection, the mice were scanned for 30 min with pinhole equipped gamma camera. Higher uptake of (99m)Tc-DMSA was measured in normal kidneys of uni-lateral I/R model and nephrectomized kidney I/R model at 3 wk post-surgery. Comparing the restoration capacities of the affected kidneys of nephrectomy, uni- and bi-lateral I/R models, higher repair capacity was observed in the nephrectomized model followed by bi-lateral then uni-lateral models. The normal kidney may retard the restoration of damaged kidney in uni-lateral I/R model. Moreover, 3 wk after Uni-I/R, the size of injured kidney was significantly smaller than non-ischemic contralateral and sham operated kidneys, while nephrectomy I/R kidneys were significantly enlarged compared to all others at 3 wk post-surgery. Very strong correlation between (99m)Tc-DMSA uptake and weight of dissected kidneys in I/R models was observed. Consistent with (99m)Tc-DMSA uptake results, all histological results indicate that kidney recovery after injury is correlated with the amount of intact tubules and kidney sizes. In summary, our study showed good potentials of (99m)Tc-DMSA scan as a promising non-invasive method for evaluation of kidney restoration after I/R injuries. Interestingly, mice with Bi-I/R injury showed faster repair capacity than those with uni-I/R. Copyright © 2011 Elsevier Inc. All rights reserved.

Tc-99m-DMSA renal uptake rate and renal volume of elderly persons

International Nuclear Information System (INIS)

Ohishi, Yukihiko; Machida, Toyohei; Kido, Akira

1987-01-01

Renal function of erderly persons was evaluated by the radionuclide renal function test based on the renal uptake rate and the renal volume determined by Tc-99m-DMSA transectional tomographic images using single photon emission computed tomography (SPECT). Forty-three erderly cases (13 healthy persons and 30 patients with various types of renal disorders) aged between 60 and 87 on an average of 70 were studied and compared with results obtained from 20 healthy adults (18 - 45 years old). Renal volume was calculated from the summation of voxels in the region districted by equi-count threshold level (percentage to maximum count) on each section of the SPECT image. Attenuation correction was made by GE-STAR protocol utilizing Sorrenson's precorrection method. The renal uptake rate was expressed as a percentage of the total radioactivity detected within the renal volume, against an amount of dose injected. In the 26 kidneys of 13 healthy elderly persons, Tc-99m-DMSA renal uptake was 23 ± 5 %, which was significantly lower (p < 0.01) than that of healthy adults being 27 ± 2 %. A correlation coefficient between renal volume and uptake of 79 kidneys of 43 elderly persons was 0.5081 (p < 0.01). Creatinine clearance (Ccr) was better correlated with the total renal uptake (r = 0.6471, p < 0.01) than with the total renal volume (r = 0.3592, p < 0.01). This method is considered to be useful for clinical purpose as a test of renal function for elderly persons since it requires neither blood nor urine samples. (author)

Evaluation of renal uptake on [sup 111]InCl[sub 3] bone marrow scintigraphy in patients with aplastic anemia and myelodysplastic syndrome

Energy Technology Data Exchange (ETDEWEB)

Koizumi, Mitsuru; Goto, Masafumi; Nomura, Toshiharu; Watari, Tsutomu; Saito, Kenji (Dokkyo Univ. School of Medicine, Mibu, Tochigi (Japan))

1993-04-01

High renal uptake on bone marrow scan with indium-111 chloride is often shown in patients with bone marrow abnormality. We evaluated the renal uptake on bone marrow scan in 27 cases of aplastic anemia, 20 cases of myelodysplastic syndrome (MDS) and 10 cases of other diseases. The high renal uptake was observed in patients not only with aplastic anemia but also with MDS. The renal uptake correlated with blood transfusion units, unsaturated iron binding capacity (UIBC), blood pool imaging and bone marrow uptake. The renal uptake correlated with UIBC better than with the blood transfusion units. Following mechanism of the renal uptake is proposed that frequent blood transfusion makes low UIBC, and the low UIBC causes the failure to chelate indium with transferrin. The fast blood clearance of un-chelated indium via kidneys is followed. Hypoplastic bone marrow may also play an important role for the high renal uptake because all patients with the high renal uptake could not be explained by above mentioned mechanism. Caution should be paid to the scans with the high renal uptake because both aplastic anemia and MDS patients show the high renal uptake. (author).

PET imaging and biodistribution analysis of the effects of succinylated gelatin combined with L-lysine on renal uptake and retention of ⁶⁴Cu-cyclam-RAFT-c(-RGDfK-)₄ in vivo.

Science.gov (United States)

Jin, Zhao-Hui; Furukawa, Takako; Sogawa, Chizuru; Claron, Michael; Aung, Winn; Tsuji, Atsushi B; Wakizaka, Hidekatsu; Zhang, Ming-Rong; Boturyn, Didier; Dumy, Pascal; Fujibayashi, Yasuhisa; Saga, Tsuneo

2014-04-01

(64)Cu-cyclam-RAFT-c(-RGDfK-)4, an αVβ3 integrin-targeting tetrameric cyclic RGD peptide probe, is a potential theranostic compound for positron emission tomography (PET) of tumor angiogenesis and for internal radiotherapy owing to the multiple decay modes of (64)Cu. Since kidneys are dose-limiting organs in internal radiotherapy, we aimed to reduce the renal accumulation of (64)Cu-cyclam-RAFT-c(-RGDfK-)4 by co-injection with Gelofusine (GF), a succinylated gelatin solution, and/or L-lysine (Lys), and to explore, for the first time, the related mechanisms using the noninvasive and quantitative PET imaging technology. Biodistribution assays, dynamic and static PET scans, and metabolism studies with radio-thin-layer chromatography (radio-TLC) were performed in healthy or αVβ3-positive tumor-bearing mice. In the results, co-injection with GF markedly reduced the renal uptake and slightly increased the tumor uptake of (64)Cu-cyclam-RAFT-c(-RGDfK-)4. L-Lysine alone had no effect on the probe biodistribution, but the combined use of Lys and GF tended to enhance the effect of GF. Dynamic PET and metabolite analysis by radio-TLC highly revealed that GF blocks the renal reabsorption of (64)Cu-cyclam-RAFT-c(-RGDfK-)4, but does not interfere with its metabolism and excretion. In conclusion, administration of GF and Lys is a useful strategy for kidney protection in (64)Cu-cyclam-RAFT-c(-RGDfK-)4-based internal radiotherapy. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

Blood Pressure Response to Main Renal Artery and Combined Main Renal Artery Plus Branch Renal Denervation in Patients With Resistant Hypertension.

Science.gov (United States)

Fengler, Karl; Ewen, Sebastian; Höllriegel, Robert; Rommel, Karl-Philipp; Kulenthiran, Saaraaken; Lauder, Lucas; Cremers, Bodo; Schuler, Gerhard; Linke, Axel; Böhm, Michael; Mahfoud, Felix; Lurz, Philipp

2017-08-10

Single-electrode ablation of the main renal artery for renal sympathetic denervation showed mixed blood pressure (BP)-lowering effects. Further improvement of the technique seems crucial to optimize effectiveness of the procedure. Because sympathetic nerve fibers are closer to the lumen in the distal part of the renal artery, treatment of the distal main artery and its branches has been shown to reduce variability in treatment effects in preclinical studies and a recent randomized trial. Whether this optimized technique improves clinical outcomes remains uncertain. We report a 2-center experience of main renal artery and combined main renal artery plus branches renal denervation in patients with resistant hypertension using a multielectrode catheter. Twenty-five patients with therapy-resistant hypertension underwent renal sympathetic denervation with combined main renal artery and renal branch ablation and were compared to matched controls undergoing an ablation of the main renal artery only. BP change was assessed by ambulatory measurement at baseline and after 3 months. At baseline, BP was balanced between the groups. After 3 months, BP changed significantly in the combined ablation group (systolic/diastolic 24-hour mean and daytime mean BP -8.5±9.8/-7.0±10.7 and -9.4±9.8/-7.1±13.5 mm Hg, P renal artery and branches appears to improve BP-lowering efficacy and should be further investigated. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Renal angiographic and computed tomographic evaluation of local extension of renal cell carcinoma

International Nuclear Information System (INIS)

Masuda, Fujio; Onishi, Tetsuro; Sasaki, Tadamasa; Arai, Yoshikazu; Shoji, Ryo

1981-01-01

In 23 cases of renal cell carcinoma, the degree of local invasion of carcinoma was diagnosed using renal angiography and CT, and compared with the findings obtained by operation or autopsy. Among 5 cases in which the tumor was confined to the renal capsule, accurate diagnosis could be established with renal angiography in 4 cases and with CT in all of 5 cases. Both renal angiography and CT provided correct diagnosis in 7 of 8 cases in which the tumor showed infiltration extending to the perinephric fat. Out of 5 cases with tumor invasion of renal vein or inferior vena cava, diagnosis could be established correctly by renal angiography and CT in 3 cases. Among the remaining 2 cases the diagnosis could be established by renal angiography and CT in one each case. Among 5 cases with metastases to the regional lymph nodes, diagnosis could be established by renal angiography in only 2 cases, while all of 5 cases could be diagnosed by CT. In 3 cases where the tumor invaded an ajacent organ beyond Gerota's fastia, renal angiography could diagnose in none of the 3 cases while with CT all of 3 cases could successfully be diagnosed. The consistency of degree of local invasion as revealed by renal angiography and CT was seen in 15 of 23 cases (65%) for renal agniography and 20 of 23 cases (87%) for CT, indicating superiority of CT in this respect. In particular, CT appears to be more superior to renal angiography for determining whether the tumor confined to Gerota's fastia or it infiltrated over it. Both combined use of renal angiography and CT, the degree of infiltration of tumor could be diagnosed correctly in 22 of 23 cases (96%). (author)

Clinical application of calculated split renal volume using computed tomography-based renal volumetry after partial nephrectomy: Correlation with technetium-99m dimercaptosuccinic acid renal scan data.

Science.gov (United States)

Lee, Chan Ho; Park, Young Joo; Ku, Ja Yoon; Ha, Hong Koo

2017-06-01

To evaluate the clinical application of computed tomography-based measurement of renal cortical volume and split renal volume as a single tool to assess the anatomy and renal function in patients with renal tumors before and after partial nephrectomy, and to compare the findings with technetium-99m dimercaptosuccinic acid renal scan. The data of 51 patients with a unilateral renal tumor managed by partial nephrectomy were retrospectively analyzed. The renal cortical volume of tumor-bearing and contralateral kidneys was measured using ImageJ software. Split estimated glomerular filtration rate and split renal volume calculated using this renal cortical volume were compared with the split renal function measured with technetium-99m dimercaptosuccinic acid renal scan. A strong correlation between split renal function and split renal volume of the tumor-bearing kidney was observed before and after surgery (r = 0.89, P volumetry had a strong correlation with the split renal function measured using technetium-99m dimercaptosuccinic acid renal scan. Computed tomography-based split renal volume measurement before and after partial nephrectomy can be used as a single modality for anatomical and functional assessment of the tumor-bearing kidney. © 2017 The Japanese Urological Association.

Assessment of relative individual renal function based on DMSA uptake corrected for renal size

International Nuclear Information System (INIS)

Estorch, M.; Camacho, V.; Tembl, A.; Mena, I.; Hernandez, A.; Flotats, A.; Carrio, I.; Torres, G.; Prat, L.

2002-01-01

Decreased relative renal DMSA uptake can be a consequence of abnormal kidney size, associated with normal or impaired renal function. The quantification of relative renal function based on DMSA uptake in both kidneys is an established method for the assessment of individual renal function. Aim: To assess relative renal function by means of quantification of renal DMSA uptake corrected for kidney size. Results were compared with relative renal DMSA uptake without size correction, and were validated against the absolute renal DMSA uptake. Material and Methods: Four-hundred-forty-four consecutive patients (147 adults, mean age 14 years) underwent a DMSA study for several renal diseases. The relative renal function, based on the relative DMSA uptake uncorrected and corrected for renal size, and the absolute renal DMSA uptake were calculated. In order to relate the relative DMSA uptake uncorrected and corrected for renal size with the absolute DMSA uptake, subtraction of uncorrected (SU) and corrected (SC) relative uptake percentages of each pair of kidneys was obtained, and these values were correlated to the matched subtraction percentages of absolute uptake (SA). If the individual relative renal function is normal (45%-55%), the subtraction value is less or equal to 10%. Results: In 227 patients (51%) the relative renal DMSA uptake value was normal either uncorrected or corrected for renal size (A), and in 149 patients (34%) it was abnormal by both quantification methods (B). Seventy-seven patients (15%) had the relative renal DMSA uptake abnormal only by the uncorrected method (C). Subtraction value of absolute DMSA uptake percentages was not significantly different of subtraction value of relative DMSA uptake percentages corrected for renal size when relative uncorrected uptake was abnormal and corrected normal. where * p<0.0001, and p=NS. Conclusion: When uncorrected and corrected relative DMSA uptake are abnormal, the absolute uptake is also impaired, while when

Alteraciones renales en la drepanocitosis Renal disorders in sickle cell disease

Directory of Open Access Journals (Sweden)

Aramís Núñez-Quintana

2011-06-01

Full Text Available La drepanocitosis está asociada con un amplio espectro de alteraciones renales que tienen su base en la falciformación de los eritrocitos en los vasos de la médula renal, que conduce a fenómenos de isquemia, microinfartos y anomalías de la función tubular. Se producen también alteraciones glomerulares funcionales reversibles de la autorregulación renal (hiperfiltración, que pueden conducir a cambios anatómicos irreversibles con glomeruloesclerosis segmentaria focal. Estas anomalías se expresan tempranamente como microalbuminuria, proteinuria y de forma mas tardía, como síndrome nefrótico e insuficiencia renal crónica. Medidas terapéuticas como el uso de inhibidores de la enzima convertidora de la angiotensina II, de los bloqueadores del receptor de la angiotensina II, asociados o no con la hidroxiurea, pueden prevenir o retardar el daño glomerular. En el presente trabajo se exponen de forma resumida aspectos relacionados con la fisiopatología del daño renal en la drepanocitosis y su tratamiento.Sickle cell disease is associated with a wide range of renal disorders resulting from the falciformation of erythrocytes in vessels of the renal medulla, leading to ischemia, microinfarctions and tubular function abnormalities. Reversible glomerular functional renal self-regulation disorders (hyperfiltration also occur, which may lead to irreversible anatomical changes with focal segmental glomerular sclerosis. These anomalies are expressed at an early stage as microalbuminuria and proteinuria, and at a later stage as nephrotic syndrome and chronic renal failure. Therapeutic measures such as the use of angiotensin-II converting enzyme inhibitors and angiotensin-II receptor blockers, associated or not with hydroxyurea, may either prevent or delay glomerular damage. The paper succinctly presents the physiopathology of renal damage in drepanocytosis and its treatment.

[Renal transplantation program at the Centenario Hospital Miguel Hidalgo in Aguascalientes, Mexico].

Science.gov (United States)

Reyes-Acevedo, Rafael; Romo-Franco, Luis; Delgadillo-Castañeda, Rodolfo; Orozco-Lozano, Iraida; Melchor-Romo, Miriam; Gil-Guzmán, Enrique; Lupercio-Luévano, Salvador; Cervantes, Sandra; Dávila, Imelda; Chew-Wong, Alfredo

2011-09-01

Miguel Hidalgo Hospital in Aguascalientes is dependent from the Federal Secretary of Health and operates in integrity with State health system in Aguascalientes. It capacity is based on 132 censored beds and 71 no censored beds. Is considered a specialty hospital in the region of Bajío. Renal transplant program activity was initiated in 1990 and gives care for adult and pediatric population. Retrospective, comparative and longitudinal study to describe and analyze our experience. Data base and clinical charts of renal transplant recipients were reviewed. Age, gender, date of transplant, etiology of renal disease, type of donor, HLA compatibility and PRA, immunosuppressive therapy, acute rejection, serum creatinina, graft loss and mortality were registered. Statistical analysis included 2, unpaired Student T test and Kaplan-Meier survival analysis with Log Rank test. Cox Analysis was also done. 1050 renal transplants were done from November 1990 to June 2011. 50 were excluded because follow-up was not longer than 3 months. 1000 consecutive renal transplant patients from January 1995 to June 2011 were included for analysis. Patients were divided in 2 groups: group A transplanted January 1995 to December 2004; group B transplanted January 2005 to June 2011. Etiology for end stage renal disease is unknown in 61% of cases, 11% developed renal disease to diabetes mellitus. 93% patient survival was observed at median follow-up and 84.9% graft survival at median follow-up (6 years). Biopsy proven acute rejection in group A 19.9 vs. 10% in group B. Two haplotype matching shows 92% graft survival. Diabetic patients exhibit 73% graft survival vs. other as hypertension (87%). PRA >0 and serum creatinine > 2.0 mg/dL increase risk for graft loss according to Cox analysis. CONCLUSION. Results are comparable to international data. Importance of developing regional transplant centers is emphasized.

Changes in the renin-angiotensin-aldosterone system in response to dietary salt intake in normal and hypertensive pregnancy. A randomized trial

DEFF Research Database (Denmark)

Nielsen, Lise Hald; Ovesen, Per; Hansen, Mie R

2016-01-01

It was hypothesized that primary renal sodium retention blunted the reactivity of the renin-angiotensin-aldosterone system to changes in salt intake in preeclampsia (PE). A randomized, cross-over, double-blinded, dietary intervention design was used to measure the effects of salt tablets or place...... of plasma renin and angiotensin II in response to changes in dietary salt intake compatible with a primary increase in renal sodium reabsorption in hypertensive pregnancies.......It was hypothesized that primary renal sodium retention blunted the reactivity of the renin-angiotensin-aldosterone system to changes in salt intake in preeclampsia (PE). A randomized, cross-over, double-blinded, dietary intervention design was used to measure the effects of salt tablets or placebo...

A Renal Perforating Artery Mistaken for Arterial Bleeding after Percutaneous Renal Biopsy: A Case Report

International Nuclear Information System (INIS)

Kim, Ye Lim; Lee, Chang Hee; Kim, Kyeong Ah; Park, Cheol Min

2009-01-01

Perirenal hematoma after a renal biopsy is a common complication that usually resolves spontaneously, but this rarely requires transfusions or surgical/radiological intervention. We report here on a case of a renal perforating artery that was mistaken for renal arterial bleeding in a 53-year-old woman who was complicated with perirenal hematoma after undergoing a percutaneous renal biopsy. On the color and pulsed wave Doppler ultrasonography, linear blood flow was seen in the perirenal hematoma, which extended perpendicularly from the renal parenchyma into the perirenal space, and this linear blood flow exhibited an arterial pulse wave. On CT angiography, the renal perforating artery was demonstrated as a curvilinear vessel coursing tangentially to the renal margin and we decided that it was a pseudolesion caused by the renal perforating artery. A renal perforating artery may be mistaken for renal arterial bleeding after a percutaneous renal biopsy. A renal perforating artery and arterial bleeding can be differentiated by the location and shape seen on a color Doppler examination and the pulse waves characteristics

A Renal Perforating Artery Mistaken for Arterial Bleeding after Percutaneous Renal Biopsy: A Case Report

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Kim, Ye Lim; Lee, Chang Hee; Kim, Kyeong Ah; Park, Cheol Min [Korea University College of Medicine, Seoul (Korea, Republic of)

2009-12-15

Perirenal hematoma after a renal biopsy is a common complication that usually resolves spontaneously, but this rarely requires transfusions or surgical/radiological intervention. We report here on a case of a renal perforating artery that was mistaken for renal arterial bleeding in a 53-year-old woman who was complicated with perirenal hematoma after undergoing a percutaneous renal biopsy. On the color and pulsed wave Doppler ultrasonography, linear blood flow was seen in the perirenal hematoma, which extended perpendicularly from the renal parenchyma into the perirenal space, and this linear blood flow exhibited an arterial pulse wave. On CT angiography, the renal perforating artery was demonstrated as a curvilinear vessel coursing tangentially to the renal margin and we decided that it was a pseudolesion caused by the renal perforating artery. A renal perforating artery may be mistaken for renal arterial bleeding after a percutaneous renal biopsy. A renal perforating artery and arterial bleeding can be differentiated by the location and shape seen on a color Doppler examination and the pulse waves characteristics

Renal venogram

Science.gov (United States)

... be black. Other structures will be shades of gray. Veins are not normally seen in an x- ... Venogram - kidney; Renal vein thrombosis - venogram Images Kidney anatomy Kidney - blood and urine flow Renal veins References ...

Lower pole renal cut injury due to the iliac wing fracture: A rare case report

Directory of Open Access Journals (Sweden)

Çaglar Yildirim

2015-07-01

Full Text Available The most frequent causes of blunt genitourinary injuries are falls from heights, motor vehicle accidents and sports injuries. Firearm injuries and penetrating stab wounds are also frequently encountered. Skeletal system traumas in the vicinity of the urogenital system can cause urological organ injuries. Though rarely, renal traumas can be dependent on the kinetic energy of the trauma and the retroperitoneal movement capacity of the kidneys and cannot be explained with the proximity of the kidney to the skeletal system. In cases with high-energy decelerations, renal pedicle and ureteropelvic junction traumas are more frequently observed. Herein, we presented a grade 3 left kidney lower pole injury developed secondary to A2 type pelvic fracture following a high energy deceleration trauma. It should not be forgotten that especially in this type of fractures, injuries of the lower renal pole can occur.

[Anatomy character of renal artery and treatment of living-donor renal transplantation].

Science.gov (United States)

Zhang, Lei; Fei, Ji-guang; Chen, Li-zhong; Wang, Chang-xi; Deng, Su-xiong; Qiu, Jiang; Li, Jun; Chen, Guo-dong; Huang, Gang

2009-12-15

To study the anatomy characters of renal artery and the treatment of multiple arteries in living donor renal grafts. Records of 142 living donors were analyzed in our center. We analyzed the anatomic structure of renal arteries by DSA and CTA pre-transplantation. Thirty-one kidneys with multiple arteries were transplanted after reconstruction. Then clinical effects were compared between multiple-renal-arteries group (n=31) and single-renal-artery group (n=111). The incidence of multiple renal artery was 30.99%, and there was no difference between both sides (left kidney 22.54%, right kidney 22.13%). If the multiple artery occurred in left or right kidney, the incidence of the multiple artery occurred in the other side was 56.25% and 60.00%, respectively. The diameter of left main renal artery was more magnanimous (P=0.001) and the first branch was more closed to abdominal aorta (P=0.004). Operation time and warm/cool ischemia time were longer in the multiple-renal-arteries group. However, estimated blood loss, delayed graft function, acute rejection and flow rate of arcuate artery were similar in both groups, the same as serum creatinine and serum creatinine clearance rate on day 7, 1 month and 3 month post-operation. It was shown by repeated measures ANOVA that graft with multiple arteries didn't affect the tendency of renal function at early time post-operation. Comprehending the character of renal artery and accurate treatment of multiple artery anastomosis are critical for the effect of the living kidney transplantation.

Preemptive Renal Transplantation-The Best Treatment Option for Terminal Chronic Renal Failure.

Science.gov (United States)

Arze Aimaretti, L; Arze, S

2016-03-01

Renal transplantation is the best therapeutic option for end-stage chronic renal disease. Assuming that it is more advisable if performed early, we aimed to show the clinical, social, and economic advantages in 70% of our patients who were dialyzed only for a short period. For this purpose, we retrospectively collected data over 28 years in 142 kidney transplants performed in patients with renal transplantation with renal failure, especially in developing countries such as Bolivia, where until last year, full public support for renal replacement therapy was unavailable. Copyright © 2016 Elsevier Inc. All rights reserved.

Albumin uptake by renal lymphatics with and without obstruction of the renal vein

International Nuclear Information System (INIS)

Threefoot, S.A.; Pearson, J.E. Jr.; Georgiardis, A.

1989-01-01

Experiments involving injection of radio-iodinated albumin into the left renal arteries or left ureters of dogs indicate that the renal lymphatics are capable of a major contribution in returning to the circulation albumin (or other large molecules) escaping from renal capillaries. I-131-albumin was injected into the jugular vein of controls or into the left renal artery or in retrograde manner into the left ureter of female dogs. Experimental groups included those with no obstruction, occlusion of left renal veins or left renal lymphatics, or both. Collections were made from the right femoral artery, both renal veins, thoracic duct and both ureters at frequent intervals for 2 to 4 hours. Data analysis included I-131 concentration, specific activity, rate of recovery and selected ratios. After renal arterial injection, the percentage of I131 recovered in thoracic duct lymph of dogs without renal venous obstruction was 5 to 10 times that recovered in those that received injections into the jugular vein. In dogs with renal venous obstruction, recovery from the thoracic duct was 10 to 1,000 times that in control dogs. Most of the differences occurred during the first hour, after which time as recirculation and redistribution occurred the rates of appearance in thoracic duct lymph in each group were similar. The differences in the ratios of concentration in thoracic duct lymph to concentration in femoral arterial blood were also much greater when the renal vein was obstructed than in dogs with no obstruction. The greater return of albumin through the thoracic duct in those with impeded renal venous outflow was probably related to both sequestered concentration and increased intrarenal pressure

Incidental renal neoplasms

DEFF Research Database (Denmark)

Rabjerg, Maj; Mikkelsen, Minne Nedergaard; Walter, Steen

2014-01-01

On the basis of associations between tumor size, pathological stage, histological subtype and tumor grade in incidentally detected renal cell carcinoma vs symptomatic renal cell carcinoma, we discussed the need for a screening program of renal cell carcinoma in Denmark. We analyzed a consecutive...... series of 204 patients with renal tumors in 2011 and 2012. The tumors were classified according to detection mode: symptomatic and incidental and compared to pathological parameters. Eighty-nine patients (44%) were symptomatic, 113 (55%) were incidental. Information was not available in two patients...

Renal function study assessed by 99mTc-DMSA renal scintigraphy before and after PNL

International Nuclear Information System (INIS)

Sakurai, Masaki; Hioki, Takuichi; Okuno, Toshiyuki; Sugimura, Yoshiki; Yamakawa, Kensuke; Yanagawa, Makoto; Tajima, Kazuhiro; Tochigi, Hiromi; Kawamura, Juichi

1990-01-01

99m Tc-DMSA renal scintigraphy was carried out in 54 patients with unilateral renal stones before and after PNL. Four to 8 weeks after PNL the DMSA renal uptake significantly decreased to 17.2±6.0% from 18.2±6.7% before PNL. DMSA renal uptake did not change in the contralateral side. Since in some patients changes in the DMSA renal uptake of 5-7% were observed after PNL not only in the PNL side but also in the contralateral side, the renal function was assessed by the formula: DMSA renal uptake in the PNL side/DMSA renal uptake in the contralateral side, and the change of this ratio was evaluated in 44 patients, in whom the renal DMSA uptake in the PNL side was less than two times that in the contralateral side. The DMSA renal uptake ratio decreased to 95.6±8.7% from the base line 4-8 weeks after PNL. This change was statistically significant. Some functional risks such as massive bleeding with PNL, the fever after PNL and the number of nephrostomy tract did not affect the decrease in the renal function. In 29 patients in whom renal function was reevaluated one year after PNL, the DMSA renal uptake ratio significantly decreased to 94.2±9.6% from the base line 4-8 weeks after PNL. But the ratio significantly improved to 99.6±11.6% about one year after PNL. In two patients with a cold area on the renal image, the renal function of the operated side still remained at about 80% levels from the base line even one year after PNL. It is concluded that although renal function slightly decreased 4-8 weeks after PNL, it is expected to improve within one year after PNL. But in the case with a cold area on the renal image, the complete functional recovery would not be expected. 99m Tc-DMSA renal scintigraphy is a useful adjunct to evaluate the renal function before and after PNL. (author)

Renal artery and parenchymal changes after renal denervation: assessment by magnetic resonance angiography

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Sanders, Margreet F.; Vink, Eva E.; Blankestijn, Peter J. [University Medical Center Utrecht, Department of Nephrology and Hypertension, PO Box 85500, Utrecht (Netherlands); Doormaal, Pieter Jan van; Habets, Jesse; Vonken, Evert-Jan; Leiner, Tim [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Beeftink, Martine M.A.; Verloop, Willemien L.; Voskuil, Michiel [University Medical Center Utrecht, Department of Cardiology, Utrecht (Netherlands); Bots, Michiel L. [University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); Fadl Elmula, Fadl Elmula M. [Oslo University Hospital, Department of Internal Medicine and Department of Cardiology, Ullevaal, Oslo (Norway); Hammer, Frank [Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Department of Radiology, Brussels (Belgium); Hoffmann, Pavel [Oslo University Hospital, Section for Interventional Cardiology, Department of Cardiology, Ullevaal, Oslo (Norway); Jacobs, Lotte; Staessen, Jan A. [University of Leuven, Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, KU Leuven Department of Cardiovascular Sciences, Leuven (Belgium); Mark, Patrick B.; Taylor, Alison H. [University of Glasgow, Institute of Cardiovascular and Medical Sciences, Glasgow, Scotland (United Kingdom); Persu, Alexandre; Renkin, Jean [Universite Catholique de Louvain, Pole of Cardiovascular Research, Institut de Recherche Experimentale et Clinique, Brussels (Belgium); Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Cardiology Department, Brussels (Belgium); Roditi, Giles [Glasgow Royal Infirmary, Department of Radiology, Glasgow (United Kingdom); Spiering, Wilko [University Medical Centre Utrecht, Department of Vascular Medicine, Utrecht (Netherlands); Collaboration: on behalf of the European Network COordinating research on Renal Denervation (ENCOReD) Consortium

2017-09-15

Relatively little is known about the incidence of long-term renal damage after renal denervation (RDN), a potential new treatment for hypertension. In this study the incidence of renal artery and parenchymal changes, assessed with contrast-enhanced magnetic resonance angiography (MRA) after RDN, is investigated. This study is an initiative of ENCOReD, a collaboration of hypertension expert centres. Patients in whom an MRA was performed before and after RDN were included. Scans were evaluated by two independent, blinded radiologists. Primary outcome was the change in renal artery morphology and parenchyma. MRAs from 96 patients were analysed. Before RDN, 41 renal anomalies were observed, of which 29 mostly mild renal artery stenoses. After a median time of 366 days post RDN, MRA showed a new stenosis (25-49% lumen reduction) in two patients and progression of pre-existing lumen reduction in a single patient. No other renal changes were observed and renal function remained stable. We observed new or progressed renal artery stenosis in three out of 96 patients, after a median time of 12 months post RDN (3.1%). Procedural angiographies showed that ablations were applied near the observed stenosis in only one of the three patients. (orig.)

Hyperglycemia induced damage to mitochondrial respiration in renal mesangial and tubular cells: Implications for diabetic nephropathy

Directory of Open Access Journals (Sweden)

Anna Czajka

2016-12-01

Full Text Available Damage to renal tubular and mesangial cells is central to the development of diabetic nephropathy (DN, a complication of diabetes which can lead to renal failure. Mitochondria are the site of cellular respiration and produce energy in the form of ATP via oxidative phosphorylation, and mitochondrial dysfunction has been implicated in DN. Since the kidney is an organ with high bioenergetic needs, we postulated that hyperglycemia causes damage to renal mitochondria resulting in bioenergetic deficit. The bioenergetic profiles and the effect of hyperglycemia on cellular respiration of human primary mesangial (HMCs and proximal tubular cells (HK-2 were compared in normoglycemic and hyperglycemic conditions using the seahorse bio-analyzer. In normoglycemia, HK-2 had significantly lower basal, ATP-linked and maximal respiration rates, and lower reserve capacity compared to HMCs. Hyperglycemia caused a down-regulation of all respiratory parameters within 4 days in HK-2 but not in HMCs. After 8 days of hyperglycemia, down-regulation of respiratory parameters persisted in tubular cells with compensatory up-regulated glycolysis. HMCs had reduced maximal respiration and reserve capacity at 8 days, and by 12 days had compromised mitochondrial respiration despite which they did not enhance glycolysis. These data suggest that diabetes is likely to lead to a cellular deficit in ATP production in both cell types, although with different sensitivities, and this mechanism could significantly contribute to the cellular damage seen in the diabetic kidney. Prevention of diabetes induced damage to renal mitochondrial respiration may be a novel therapeutic approach for the prevention/treatment of DN.

Renal Function in Hypothyroidism

International Nuclear Information System (INIS)

Khalid, S.; Khalid, M; Elfaki, M.; Hassan, N.; Suliman, S.M.

2007-01-01

Background Hypothyroidism induces significant changes in the function of organ systems such as the heart, muscles and brain. Renal function is also influenced by thyroid status. Physiological effects include changes in water and electrolyte metabolism, notably hyponatremia, and reliable alterations of renal hemodynamics, including decrements in renal blood flow, renal plasma flow, glomerular filtration rate (GFR). Objective Renal function is profoundly influenced by thyroid status; the purpose of the present study was to determine the relationship between renal function and thyroid status of patients with hypothyroidism. Design and Patients In 5 patients with primary hypothyroidism and control group renal functions are measured by serum creatinine and glomerular filtration rate (GFR) using modified in diet renal disease (MDRD) formula. Result In hypothyroidism, mean serum creatinine increased and mean estimated GFR decreased, compared to the control group mean serum creatinine decreased and mean estimated GFR Increased. The hypothyroid patients showed elevated serum creatinine levels (> 1.1mg/dl) compared to control group (p value .000). In patients mean estimated GFR decreased, compared to mean estimated GFR increased in the control group (p value= .002).

The Swedish infant high-grade reflux trial: UTI and renal damage.

Science.gov (United States)

Nordenström, Josefin; Sjöström, Sofia; Sillén, Ulla; Sixt, Rune; Brandström, Per

2017-04-01

High-grade vesicoureteral reflux (VUR) in children is associated with recurrent urinary tract infection (UTI) and renal damage. Breakthrough UTI despite continuous antibiotic prophylaxis (CAP) during the first years of life is a matter of concern and evokes early intervention. We investigated whether early endoscopic treatment (ET) of VUR grade 4-5 can reduce the risk of UTI recurrence and renal scarring. This prospective, randomized, controlled, multicentre, 1-year follow-up trial comprised 77 infants, UTIs were reported. There were 27 recurrent febrile UTIs in 6 (16%) children in the ET group and in 10 (26%) in the CAP group (p = 0.43), in eight (36%) girls and eight (15%) boys (p = 0.039). Successful VUR outcome (VUR 0-2) was seen in 22 (59%) in the ET and eight (21%) in the CAP group (p = 0.0014). Multiple recurrences were only seen in patients with persistent dilating reflux at follow-up (p = 0.019). Deterioration on scintigraphy was seen in eight children (9 kidneys) with no difference between treatment groups (p = 0.48) or sex (p = 0.17). Renal deterioration was associated with high bladder capacity (BC) and large residual volume (PVR) at 1 year (p = 0.0092 and p = 0.041). Six of the eight children with renal deterioration had a recurrent UTI (p = 0.0032). Seven of nine renal units with deterioration were seen in children with persistent VUR 3-5 at follow-up. Univariable logistic regression identified female sex and high PVR as positive predictors for recurrent UTI (p = 0.039 and 0.034) and high PVR tended to predict renal deterioration (p = 0.053). No differences between the treatment groups regarding recurrent UTI and renal deterioration could be found. Increased PVR and female sex were positive predictors for UTI recurrences. VUR grade at follow-up was correlated to UTI recurrence and renal deterioration. This study did not show any difference between ET and CAP in reducing the risk of UTI recurrence or renal deterioration. The rate

Phytate (IP6) is a powerful agent for preventing calcifications in biological fluids: usefulness in renal lithiasis treatment.

Science.gov (United States)

Grases, F; Costa-Bauzá, A

1999-01-01

The extraordinary capacity of phytate (myo-inositol hexaphosphate), a substance present in blood, urine, interstitial and intracellular fluids, to inhibit crystallization of calcium salts (oxalate and phosphate) is discussed. Its role in preventing calcium renal stone formation is specifically presented and discussed. "In vitro" and "in vivo" experiments, as well as clinical studies clearly demonstrated that phytate plays an important role as a crystallization inhibitor of calcium salts in biological fluids and becomes a clear alternative in the treatment of calcium oxalate renal lithiasis.

Renal Sinus Fat Invasion and Tumoral Thrombosis of the Inferior Vena Cava-Renal Vein: Only Confined to Renal Cell Carcinoma

OpenAIRE

Turker Acar; Mustafa Harman; Serkan Guneyli; Sait Sen; Nevra Elmas

2014-01-01

Epithelioid angiomyolipoma (E-AML), accounting for 8% of renal angiomyolipoma, is usually associated with tuberous sclerosis (TS) and demonstrates aggressive behavior. E-AML is macroscopically seen as a large infiltrative necrotic tumor with occasional extension into renal vein and/or inferior vena cava. However, without history of TS, renal sinus and venous invasion E-AML would be a challenging diagnosis, which may lead radiologists to misinterpret it as a renal cell carcinoma (RCC). In this...

Acute renal failure in children

International Nuclear Information System (INIS)

Vergesslich, K.A.; Balzar, E.; Weninger, M.; Ponhold, W.; Sommer, G.; Wittich, G.R.; Vienna Univ.

1987-01-01

Acute renal failure (ARF) may be due to obstructive uropathy or renal parenchymal disease. Twenty-five children with acute renal failure secondary to renal parenchymal disease underwent ultrasonographic examination of the kidneys. Changes of renal size and cortical echogenicity were correlated with renal function. All patients presented with bilaterally enlarged kidneys with the exception in renal function resulted in normalization of renal size. With regard to cortical echogenicity two groups were formed. Group A comprised 11 patients whose kidneys had the same echogenicity as the liver, while in group B the kidneys were more echogenic (14 patients). Cortical echogenicity was always increased. Determination of creatinine levels showed a statistically significant difference between group A (3.32 mg% ± 1.40 S.D.) and group B (5.95 mg% ± 1.96 S.D.), p < 0.001. Changes in renal function were paralleled by rapid changes in renal size and cortical echogenicity. (orig.)

Renal tolerance for iopromide (ultravist) in patients with chronic renal failure. Preliminary report

International Nuclear Information System (INIS)

Golebiowski, M.; Pruszynski, B.

1993-01-01

The authors present the renal tolerance for nonionic low-osmotic contrast agent iopromide (ultravist) on the ground of literature and of angiographic examinations in 10 patients with chronic renal failure. One patient only had significant temporary deterioration of renal function. The presented results showed that analyzed agent is less nephrotoxic than high osmolality contrast agents. The use of iopromide is strongly recommended in patients with chronic renal failure. The risk of depression of renal function after administration of contrast material is minimized. (author)

Effect of Shenkang injection combined with hemodialysis treatment on renal function, renal anemia and cytokine levels in patients with chronic renal failure

Directory of Open Access Journals (Sweden)

Rui Liu

2016-10-01

Full Text Available Objective: To study the effect of Shenkang injection combined with hemodialysis treatment on renal function, renal anemia and cytokine levels in patients with chronic renal failure. Methods: A total of 68 patients with chronic renal failure who received hemodialysis treatment in our hospital during between October 2013 and February 2016 were selected and randomly divided into two groups, the observation group received Shenkang injection treatment in the process of dialysis, and the control group only received conventional symptomatic and supportive treatment. 8 weeks after treatment, serum was collected to determine the levels of renal function indexes, nutritional status indexes, anemia indexes and cytokines, and urine was collected to determine renal function indexes. Results: β2-MG, UA, Cr, phosphorus, IL-17, IL-23, CTGF, TGF-β1, FGF-2 and FGF-23 levels in serum as well as NGAL, KIM-1 and RBP levels in urine of observation group were significantly lower than those of control group, and TP, Alb, PA, calcium, Hb, EPO, Fe, TRF and FER levels in serum were significantly higher than those of control group. Conclusion: Shenkang injection combined with hemodialysis treatment helps to improve renal function, nutritional status and renal anemia, and reduce the synthesis of inflammation and renal interstitial fibrosis-related cytokines in patients with chronic renal failure.

Anatomic variations of the renal vessels: focus on the precaval right renal artery.

Science.gov (United States)

Bouali, Ourdia; Labarre, David; Molinier, François; Lopez, Raphaël; Benouaich, Vincent; Lauwers, Frédéric; Moscovici, Jacques

2012-07-01

The aim of this study was to determine the prevalence of precaval right renal artery and to investigate the distribution of renal arteries and veins. We discuss a theory of development of renal vascular variants. We retrospectively reviewed 120 arterial phase contrast material-enhanced spiral computerized tomography scans of the abdomen (1- to 2-mm section thickness) performed during a two-month period. Forty percent of the study group (48 patients) had one artery and one vein on each side, with typical course. There was a 9.17% prevalence of precaval right renal artery: 10 patients had a lower pole accessory artery in precaval position and one patient had the main and the accessory arteries that pass anterior to the inferior vena cava. In these cases, associated variations of renal vessels were higher than in the patients without precaval artery variant. There were multiple arteries in 28.3% of the right kidneys and in 26.7% of the left ones. Variants of the right renal vein consisted in multiple veins in 20% (24 cases). We detected no case of multiple left renal veins, but we described variations of its course (circum- or retroaortic vein) in 9.17% (11 cases). Twenty-six patients (21.7%) had associated variations of the renal pedicle. The current technical support allows for a minimally invasive study of vessels anatomy. In our study the prevalence of a precaval right renal artery appears to be higher than previously reported (9.17%). Knowledge on anatomical variations of right renal artery and associated renal vessels variations has major clinical implications.

Renal shear wave velocity by acoustic radiation force impulse did not reflect advanced renal impairment.

Science.gov (United States)

Takata, Tomoaki; Koda, Masahiko; Sugihara, Takaaki; Sugihara, Shinobu; Okamoto, Toshiaki; Miyoshi, Kenichi; Matono, Tomomitsu; Hosho, Keiko; Mae, Yukari; Iyama, Takuji; Fukui, Takeaki; Fukuda, Satoko; Munemura, Chishio; Isomoto, Hajime

2016-12-01

Acoustic radiation force impulse is a noninvasive method for evaluating tissue elasticity on ultrasound. Renal shear wave velocity measured by this technique has not been fully investigated in patients with renal disease. The aim of the present study was to compare renal shear wave velocity in end-stage renal disease patients and that in patients without chronic kidney disease and to investigate influencing factors. Renal shear wave velocities were measured in 59 healthy young subjects (control group), 31 subjects without chronic kidney disease (non-CKD group), and 39 end-stage renal disease patients (ESRD group). Each measurement was performed 10 times at both kidneys, and the mean value of eight of 10 measurements, excluding the maximum and minimum values, was compared. Renal shear wave velocity could be measured in all subjects. Renal shear wave velocity in the control group was higher than in the non-CKD group and in the ESRD group, and no difference was found between the non-CKD group and the ESRD group. Age and depth were negatively correlated to the renal shear wave velocity. In multiple regression analysis, age and depth were independent factors for renal shear wave velocity, while renal impairment was not. There was no difference between the non-CKD group and the ESRD group, even when ages were matched and depth was adjusted. Renal shear wave velocity was not associated with advanced renal impairment. However, it reflected alteration of renal aging, and this technique may be useful to detect renal impairment in the earlier stages. © 2015 Asian Pacific Society of Nephrology.

Renal parenchyma thickness: a rapid estimation of renal function on computed tomography

International Nuclear Information System (INIS)

Kaplon, Daniel M.; Lasser, Michael S.; Sigman, Mark; Haleblian, George E.; Pareek, Gyan

2009-01-01

Purpose: To define the relationship between renal parenchyma thickness (RPT) on computed tomography and renal function on nuclear renography in chronically obstructed renal units (ORUs) and to define a minimal thickness ratio associated with adequate function. Materials and Methods: Twenty-eight consecutive patients undergoing both nuclear renography and CT during a six-month period between 2004 and 2006 were included. All patients that had a diagnosis of unilateral obstruction were included for analysis. RPT was measured in the following manner: The parenchyma thickness at three discrete levels of each kidney was measured using calipers on a CT workstation. The mean of these three measurements was defined as RPT. The renal parenchyma thickness ratio of the ORUs and non-obstructed renal unit (NORUs) was calculated and this was compared to the observed function on Mag-3 lasix Renogram. Results: A total of 28 patients were evaluated. Mean parenchyma thickness was 1.82 cm and 2.25 cm in the ORUs and NORUs, respectively. The mean relative renal function of ORUs was 39%. Linear regression analysis comparing renogram function to RPT ratio revealed a correlation coefficient of 0.48 (p * RPT ratio. A thickness ratio of 0.68 correlated with 20% renal function. Conclusion: RPT on computed tomography appears to be a powerful predictor of relative renal function in ORUs. Assessment of RPT is a useful and readily available clinical tool for surgical decision making (renal salvage therapy versus nephrectomy) in patients with ORUs. (author)

Human Urine-Derived Renal Progenitors for Personalized Modeling of Genetic Kidney Disorders.

Science.gov (United States)

Lazzeri, Elena; Ronconi, Elisa; Angelotti, Maria Lucia; Peired, Anna; Mazzinghi, Benedetta; Becherucci, Francesca; Conti, Sara; Sansavini, Giulia; Sisti, Alessandro; Ravaglia, Fiammetta; Lombardi, Duccio; Provenzano, Aldesia; Manonelles, Anna; Cruzado, Josep M; Giglio, Sabrina; Roperto, Rosa Maria; Materassi, Marco; Lasagni, Laura; Romagnani, Paola

2015-08-01

The critical role of genetic and epigenetic factors in the pathogenesis of kidney disorders is gradually becoming clear, and the need for disease models that recapitulate human kidney disorders in a personalized manner is paramount. In this study, we describe a method to select and amplify renal progenitor cultures from the urine of patients with kidney disorders. Urine-derived human renal progenitors exhibited phenotype and functional properties identical to those purified from kidney tissue, including the capacity to differentiate into tubular cells and podocytes, as demonstrated by confocal microscopy, Western blot analysis of podocyte-specific proteins, and scanning electron microscopy. Lineage tracing studies performed with conditional transgenic mice, in which podocytes are irreversibly tagged upon tamoxifen treatment (NPHS2.iCreER;mT/mG), that were subjected to doxorubicin nephropathy demonstrated that renal progenitors are the only urinary cell population that can be amplified in long-term culture. To validate the use of these cells for personalized modeling of kidney disorders, renal progenitors were obtained from (1) the urine of children with nephrotic syndrome and carrying potentially pathogenic mutations in genes encoding for podocyte proteins and (2) the urine of children without genetic alterations, as validated by next-generation sequencing. Renal progenitors obtained from patients carrying pathogenic mutations generated podocytes that exhibited an abnormal cytoskeleton structure and functional abnormalities compared with those obtained from patients with proteinuria but without genetic mutations. The results of this study demonstrate that urine-derived patient-specific renal progenitor cultures may be an innovative research tool for modeling of genetic kidney disorders. Copyright © 2015 by the American Society of Nephrology.

Renal ornithine decarboxylase activity, polyamines, and compensatory renal hypertrophy in the rat

International Nuclear Information System (INIS)

Humphreys, M.H.; Etheredge, S.B.; Lin, Shanyan; Ribstein, J.; Marton, L.J.

1988-01-01

The authors determined the role of ornithine decarboxylase (ODC) in compensatory renal hypertrophy (CRH) by relating renal ODC activity and polyamine content to kidney size, expressed as a percent of body weight, 1 wk after unilateral nephrectomy (UN). In normal rats, renal ODC activity increased after UN; 1 wk later the remaining kidney weight had increased. Renal concentration of putrescine, the product of ODC's decarboxylation of ornithine, was increased 3, 8, and 48 h after UN, but concentrations of polyamines synthesized later in the pathway, spermidine and spermine, were not appreciably affected. Pretreatment with difluoromethylornithine (DFMO), an irreversible inhibitor of ODC inhibited both base-line renal ODC activity and putrescine concentration as well as increases stimulated by UN, although concentrations of spermidine and spermine were not decreased. In hypophysectomized rats, both increased renal ODC activity and CRH occurred as well, indicating that these two consequences of UN do not require intact pituitary function. Thus stimulation of renal ODC activity and putrescine content do not appear critical to the process of CRH after UN

The rise and fall of novel renal magnesium transporters.

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Schäffers, Olivier J M; Hoenderop, Joost G J; Bindels, René J M; de Baaij, Jeroen H F

2018-06-01

Body Mg 2+ balance is finely regulated in the distal convoluted tubule (DCT), where a tight interplay among transcellular reabsorption, mitochondrial exchange, and basolateral extrusion takes place. In the last decades, several research groups have aimed to identify the molecular players in these processes. A multitude of proteins have been proposed to function as Mg 2+ transporter in eukaryotes based on phylogenetic analysis, differential gene expression, and overexpression studies. However, functional evidence for many of these proteins is lacking. The aim of this review is, therefore, to critically reconsider all putative Mg 2+ transporters and put their presumed function in context of the renal handling of Mg 2+ . Sufficient experimental evidence exists to acknowledge transient receptor potential melastatin (TRPM) 6 and TRPM7, solute carrier family 41 (SLC41) A1 and SLC41A3, and mitochondrial RNA splicing 2 (MRS2) as Mg 2+ transporters. TRPM6/7 facilitate Mg 2+ influx, SLC41A1 mediates Mg 2+ extrusion, and MRS2 and SLC41A3 are implicated in mitochondrial Mg 2+ homeostasis. These proteins are highly expressed in the DCT. The function of cyclin M (CNNM) proteins is still under debate. For the other proposed Mg 2+ transporters including Mg 2+ transporter subtype 1 (MagT1), nonimprinted in Prader-Willi/Angelman syndrome (NIPA), membrane Mg 2+ transport (MMgT), Huntingtin-interacting protein 14 (HIP14), and ATP13A4, functional evidence is limited, or functions alternative to Mg 2+ transport have been suggested. Additional characterization of their Mg 2+ transport proficiency should be provided before further claims about their role as Mg 2+ transporter can be made.

Renal pelvis urothelial carcinoma of the upper moiety in complete right renal duplex: a case report.

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Zhang, Yiran; Yu, Quanfeng; Zhang, Zhihong; Liu, Ranlu; Xu, Yong

2015-01-01

Urothelial carcinoma (UC) originated from renal pelvis is the common tumor of the urinary system, however, neoplasia of the renal pelvis in duplex kidneys is extremely rare, especially in the complete renal and ureteral duplex cases. We present the first case of renal pelvis UC of the upper moiety in a complete right renal duplex. This male patient has bilateral complete renal and ureteral duplex. To the best of our knowledge, this is the first reported case of renal pelvis UC in a complete renal duplex system. After this experience we feel that the diagnosis of renal pelvis UC in duplex kidneys is not so easy, and once the diagnosis is determined, the whole renal duplex units and bladder cuff or ectopic orifice should be excised radically.

Photon Reabsorption in Mixed CsPbCl3:CsPbI3 Perovskite Nanocrystal Films for Light-Emitting Diodes

KAUST Repository

Davis, Nathaniel J. L. K.

2017-01-24

Cesium lead halide nanocrystals, CsPbX3 (X = Cl, Br, I), exhibit photoluminescence quantum efficiencies approaching 100% without the core–shell structures usually used in conventional semiconductor nanocrystals. These high photoluminescence efficiencies make these crystals ideal candidates for light-emitting diodes (LEDs). However, because of the large surface area to volume ratio, halogen exchange between perovskite nanocrystals of different compositions occurs rapidly, which is one of the limiting factors for white-light applications requiring a mixture of different crystal compositions to achieve a broad emission spectrum. Here, we use mixtures of chloride and iodide CsPbX3 (X = Cl, I) perovskite nanocrystals where anion exchange is significantly reduced. We investigate samples containing mixtures of perovskite nanocrystals with different compositions and study the resulting optical and electrical interactions. We report excitation transfer from CsPbCl3 to CsPbI3 in solution and within a poly(methyl methacrylate) matrix via photon reabsorption, which also occurs in electrically excited crystals in bulk heterojunction LEDs.

Krogh’s principle or a multiple fish model approach to phosphate balance: is there a centrally regulated intestinal-skeletal-renal axis?

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Pedro Miguel Guerreiro

2015-10-01

Full Text Available Inorganic phosphate (Pi is a crucial ion for vertebrate life. In addition to many physiological roles it is, together with calcium, the major element forming the internal skeleton and Pi balance has been considered a secondary consequence of calciotropic endocrine factors. However, contrary to calcium which can be readily obtained from even Ca-poor environments, Pi is not available in water, and fish can only obtain it via the food. Intestinal absorption drives Pi into the blood stream, but a central part of Pi balance is renal excretion and conservation. Recently, several Pi specific regulatory factors have been brought to light, and we use fish models to investigate their role and the hypothesis of a centrally controlled intestinal-skeletal-renal Pi axis. Using tissues mounted in Ussing chambers under symmetrical and asymmetrical short-circuited conditions we measure unidirectional 33Pi fluxes and test PTHrP, but also STC and FGF23 as regulatory factors, as well as specific drugs to unveil the functional transporting mechanisms. Pi absorption is modified in starved and fed sea bass, an effect dependent on Pi availability in diet, which modifies gene expression of uptake mechanisms. Phosphate secretion across flounder primary renal cell cultures is increased by PTHrP, which reduces the expression of reabsorption mechanisms such as NaPiII and evokes an increase in GFR in cannulated fish, thus resulting in net Pi excretion. A similar effect occurs in the toadfish urinary bladder, which displays moderate Pi transport that is abolished by the drug ouabain and modified by endocrines. Finally we used the shark choroid plexus (CP to show active CSF-to-blood transport with biochemical properties consistent with PiT Na+-dependent transporters. RT-PCR revealed the PiT1/2, but no NaPiII gene expression and we localized PiT2 in CP apical membranes while PiT1 occurred in vascular endothelial cells. Shark CP expresses both PTHrP and its receptor. Could

Impact of arterial occlusion during partial nephrectomy on residual renal function. An evaluation with {sup 99m}technetium-dimercaptosuccinic acid scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Kondo, Tsunenori; Nakazawa, Hayakazu; Ito, Fumio; Onitsuka, Shiro; Ryoji, Osamu; Yago, Rie; Hashimoto, Yasunobu; Toma, Hiroshi [Tokyo Women' s Medical Coll. (Japan)

2002-08-01

Partial nephrectomy (PNx) has been performed with temporary renal arterial occlusion and in situ renal hypothermia (conventional PNx). However, the impact of temporary renal arterial occlusion on residual renal function has not been well assessed. To address this question, we performed renal scintigraphy with {sup 99m}technetium-dimercaptosuccinic acid (DMSA) for the quantitative measurement of postoperative residual renal function after conventional PNx and partial nephrectomy without arterial occlusion (non-clamping PNx). Thirty-four patients underwent postoperative DMSA scintigraphy after PNx for renal cell carcinoma. No obvious difference in preoperative renal function between the diseased kidney and the contralateral kidney was found in any of the patients. Of these patients, 24 underwent conventional PNx, and 10 underwent non-clamping PNx. Residual renal function was evaluated using the relative DMSA uptake of the operated kidney. The relative DMSA uptake of the operated kidney was 39.9{+-}7.3% (25.1-58.8) after conventional PNx compared to 34.8{+-}8.9% (13.5-45.5) after non-clamping PNx. This difference was not statistically significant (P=0.15). Total ischemic time during conventional PNx had no adverse influence on the residual renal function. In the analysis of the other determinant factors influencing residual renal function, tumor size was the only significant factor that inversely correlated with the relative DMSA uptake. Our results showed that arterial clamping during PNx has no negative impact on the functional residual capacity as long as in situ renal hypothermia is adequately performed. (author)

OBSTETRIC RENAL FAILURE

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Rajeshwari

2015-11-01

Full Text Available Renal failure in obstetrics is rare but important complication, associated with significant mortality and long term morbidity.1,2 It includes acute renal failure due to obstetrical complications or due to deterioration of existing renal disease. AIMS AND OBJECTIVES: To evaluate the etiology and outcome of renal failure in obstetric patients. METHODS: We prospectively analyzed 30 pregnant and puerperal women with acute renal failure or pre-existing renal disease developing renal failure during pregnancy between November 2007 to sep-2009. Patients who presented/developed ARF during the hospital stay were included in this study. RESULTS: Among 30 patients, mean age was 23 years and 33 years age group. 12 cases (40% patients were primigravidae and 9(30% patients were multigravidae and 9 cases (30% presented in post-partum period. Eighteen cases (60% with ARF were seen in third trimester, followed by in postpartum period 9 cases (30%. Most common contributing factors to ARF were Pre-eclampsia, eclampsia and HELLP syndrome 60%, sepsis 56.6%, post abortal ARF 10%. DIC 40%. Haemorrhage as the aetiology for ARF was present 46%, APH in 20% and PPH in 26.6%. The type of ARF was renal in (63% and prerenal (36%; Oliguric seen in 10 patients (33% and high mortality (30%. Among the 20 pregnant patients with ARF, The average period of gestation was 33±2 weeks (30 -36 weeks, 5 cases (25% presented with intrauterine fetal demise and 18 cases (66% had preterm vaginal delivery and 2 cases (10% had induced abortion. And the average birth weight was 2±0.5 kg (1.5 kg. Eight cases (26% required dialysis. 80% of patients recovered completely of renal functions. 63% patients recovered without renal replacement therapy whereas 17% required dialysis. the maternal mortality was 20%, the main reason for mortality was septic shock and multi organ dysfunction (66%. CONCLUSION: ARF related pregnancy was seen commonly in the primigravidae and in the third trimester, the most

Renal nerves dynamically regulate renal blood flow in conscious, healthy rabbits.

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Schiller, Alicia M; Pellegrino, Peter R; Zucker, Irving H

2016-01-15

Despite significant clinical interest in renal denervation as a therapy, the role of the renal nerves in the physiological regulation of renal blood flow (RBF) remains debated. We hypothesized that the renal nerves physiologically regulate beat-to-beat RBF variability (RBFV). This was tested in chronically instrumented, healthy rabbits that underwent either bilateral surgical renal denervation (DDNx) or a sham denervation procedure (INV). Artifact-free segments of RBF and arterial pressure (AP) from calmly resting, conscious rabbits were used to extract RBFV and AP variability for time-domain, frequency-domain, and nonlinear analysis. Whereas steady-state measures of RBF, AP, and heart rate did not statistically differ between groups, DDNx rabbits had greater RBFV than INV rabbits. AP-RBF transfer function analysis showed greater admittance gain in DDNx rabbits than in INV rabbits, particularly in the low-frequency (LF) range where systemic sympathetic vasomotion gives rise to AP oscillations. In the LF range, INV rabbits exhibited a negative AP-RBF phase shift and low coherence, consistent with the presence of an active control system. Neither of these features were present in the LF range of DDNx rabbits, which showed no phase shift and high coherence, consistent with a passive, Ohm's law pressure-flow relationship. Renal denervation did not significantly affect nonlinear RBFV measures of chaos, self-affinity, or complexity, nor did it significantly affect glomerular filtration rate or extracellular fluid volume. Cumulatively, these data suggest that the renal nerves mediate LF renal sympathetic vasomotion, which buffers RBF from LF AP oscillations in conscious, healthy rabbits. Copyright © 2016 the American Physiological Society.

Cardio-renal syndrome

OpenAIRE

Gnanaraj, Joseph; Radhakrishnan, Jai

2016-01-01

Cardio-renal syndrome is a commonly encountered problem in clinical practice. Its pathogenesis is not fully understood. The purpose of this article is to highlight the interaction between the cardiovascular system and the renal system and how their interaction results in the complex syndrome of cardio-renal dysfunction. Additionally, we outline the available therapeutic strategies to manage this complex syndrome.

Renal hemodynamic effects of activation of specific renal sympathetic nerve fiber groups.

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DiBona, G F; Sawin, L L

1999-02-01

To examine the effect of activation of a unique population of renal sympathetic nerve fibers on renal blood flow (RBF) dynamics, anesthetized rats were instrumented with a renal sympathetic nerve activity (RSNA) recording electrode and an electromagnetic flow probe on the ipsilateral renal artery. Peripheral thermal receptor stimulation (external heat) was used to activate a unique population of renal sympathetic nerve fibers and to increase total RSNA. Total RSNA was reflexly increased to the same degree with somatic receptor stimulation (tail compression). Arterial pressure and heart rate were increased by both stimuli. Total RSNA was increased to the same degree by both stimuli but external heat produced a greater renal vasoconstrictor response than tail compression. Whereas both stimuli increased spectral density power of RSNA at both cardiac and respiratory frequencies, modulation of RBF variability by fluctuations of RSNA was small at these frequencies, with values for the normalized transfer gain being approximately 0.1 at >0.5 Hz. During tail compression coherent oscillations of RSNA and RBF were found at 0.3-0.4 Hz with normalized transfer gain of 0.33 +/- 0.02. During external heat coherent oscillations of RSNA and RBF were found at both 0.2 and 0.3-0.4 Hz with normalized transfer gains of 0. 63 +/- 0.05 at 0.2 Hz and 0.53 +/- 0.04 to 0.36 +/- 0.02 at 0.3-0.4 Hz. Renal denervation eliminated the oscillations in RBF at both 0.2 and 0.3-0.4 Hz. These findings indicate that despite similar increases in total RSNA, external heat results in a greater renal vasoconstrictor response than tail compression due to the activation of a unique population of renal sympathetic nerve fibers with different frequency-response characteristics of the renal vasculature.

Renal computed angiography. Part I: Renal CT arteriography in hypertension

International Nuclear Information System (INIS)

Al-Amin, M.; Hadjidekov, V.

2012-01-01

Visualization of renal vasculature is needed in several clinical condition among which hypertension is dominant. CT angiography now day replaces catheter angiography as non-invasive method. The goal of this study is to present initial authors experience in visualization of renal arteries using 64 MDCT and to evaluated the utility in hypertensive patients. MDCT assures excellent assessment of renal arteries conditions. Multiplanar reconstruction and allow better delineation in tortuous vessels course and anatomic variants. (authors)

Renal sympathetic nervous system and the effects of denervation on renal arteries.

Science.gov (United States)

Kannan, Arun; Medina, Raul Ivan; Nagajothi, Nagapradeep; Balamuthusamy, Saravanan

2014-08-26

Resistant hypertension is associated with chronic activation of the sympathetic nervous system resulting in various comorbidities. The prevalence of resistant hypertension is often under estimated due to various reasons. Activation of sympathetic nervous system at the renal- as well as systemic- level contributes to the increased level of catecholamines and resulting increase in the blood pressure. This increased activity was demonstrated by increased muscle sympathetic nerve activity and renal and total body noradrenaline spillover. Apart from the hypertension, it is hypothesized to be associated with insulin resistance, congestive heart failure and obstructive sleep apnea. Renal denervation is a novel procedure where the sympathetic afferent and efferent activity is reduced by various techniques and has been used successfully to treat drug-resistant hypertension improvement of various metabolic derangements. Renal denervation has the unique advantage of offering the denervation at the renal level, thus mitigating the systemic side effects. Renal denervation can be done by various techniques including radiofrequency ablation, ultrasound guided ablation and chemical ablation. Various trials evaluated the role of renal denervation in the management of resistant hypertension and have found promising results. More studies are underway to evaluate the role of renal denervation in patients presenting with resistant hypertension in different scenarios. Appropriate patient selection might be the key in determining the effectiveness of the procedure.

Resolving an 80-yr-old controversy: the beginning of the modern era of renal physiology.

Science.gov (United States)

Jamison, Rex L

2014-12-01

Marcello Malpighi discovered the glomerulus that bears his name in the 17th century, but it was not until the middle of the 19th century, in 1842, that William Bowman in London published his studies of the histological structure of the glomerulus and proposed that urine formation begins with glomerular secretion. At nearly the same time in Marburg, Carl Ludwig, unaware of Bowman's findings, proposed that urine formation begins with glomerular filtration followed by tubule reabsorption. The controversy lasted 80 yr. Prominent investigators weighed in on both sides. Rudolph Heidenhain's findings in 1874 swung the pendulum toward Bowman's theory until Arthur Cushny published his book, The Secretion of Urine, in 1917, in which he found the evidence insufficient to prove either theory. In 1921, a young physician, Joseph Wearn, began his postresidency training in the laboratory of Alfred N. Richards. He read Cushny's book and learned how to expose the glomerulus of a living frog. Richards proposed that Wearn use that experimental preparation to inject epinephrine into the glomerulus. Wearn proposed a different experiment: instead of using injection, collect fluid from the glomerulus and analyze it. Richards agreed, and the landmark results of that experiment, published in 1924, settled the controversy. The modern era of renal physiology was born. Copyright © 2014 The American Physiological Society.

Zeeman effect on disalignment of excited atoms by radiation re-absorption: neon 2p2 atoms in a discharge plasma

International Nuclear Information System (INIS)

Deguchi, K; Imagawa, T; Shikama, T; Hasuo, M

2009-01-01

We have measured the relaxation rate of alignment of neon atoms in a 2p 2 (in Paschen notation) level, which were excited by a linearly polarized laser pulse in a glow discharge plasma at 77 K, in a magnetic field of up to 3 T in the Voigt configuration. The relaxation rate decreased with an increase in the magnetic field strength of up to 0.5 T and showed no magnetic field dependence above 0.5 T. We developed a Monte Carlo simulation method to calculate alignment relaxation, or disalignment, by radiation re-absorption of atomic resonance lines in a magnetic field. The simulated result was found to be consistent with the observed magnetic field dependence. We analysed the results of the simulation from a point of competition between the Zeeman splitting and the Doppler broadening of the transition lines from the 2p 2 level.

ERK Regulates Renal Cell Proliferation and Renal Cyst Expansion in inv Mutant Mice

International Nuclear Information System (INIS)

Okumura, Yasuko; Sugiyama, Noriyuki; Tanimura, Susumu; Nishida, Masashi; Hamaoka, Kenji; Kohno, Michiaki; Yokoyama, Takahiko

2009-01-01

Nephronophthisis (NPHP) is the most frequent genetic cause of end-stage kidney disease in children and young adults. Inv mice are a model for human nephronophthisis type 2 (NPHP2) and characterized by multiple renal cysts and situs inversus. Renal epithelial cells in inv cystic kidneys show increased cell proliferation. We studied the ERK pathway to understand the mechanisms that induce cell proliferation and renal cyst progression in inv kidneys. We studied the effects of ERK suppression by administering PD184352, an oral mitogen-activated protein kinase kinase (MEK) inhibitor on renal cyst expansion, extracellular signal-regulated protein kinase (ERK) activity, bromo-deoxyuridine (BrdU) incorporation and expression of cell-cycle regulators in invΔC kidneys. Phosphorylated ERK (p-ERK) level increased along with renal cyst enlargement. Cell-cycle regulators showed a high level of expression in invΔC kidneys. PD184352 successfully decreased p-ERK level and inhibited renal cyst enlargement. The inhibitor also decreased expression of cell-cycle regulators and BrdU incorporation in renal epithelial cells. The present results showed that ERK regulated renal cell proliferation and cyst expansion in inv mutants

Renal artery stenosis

International Nuclear Information System (INIS)

Desberg, A.; Paushter, D.M.; Lammert, G.K.; Hale, J.; Troy, R.; Novic, A.; Nally, J. Jr.

1989-01-01

Renal artery disease is a potentially correctable cause of hypertension. Previous studies have suggested the utility of duplex sonography in accurately detecting and grading the severity of renal artery stenosis. The purpose of this paper is to evaluate color flow Doppler for this use. Forty-three kidneys were examined by color-flow Doppler and conventional duplex sampling in patients with suspected renovascular hypertension or those undergoing aortography for unrelated reasons. Doppler tracings were obtained from the renal arteries and aorta with calculation of the renal aortic ratio (RAR) and resistive index (RI). Results of Doppler sampling with color flow guidance were compared with aortograms in a blinded fashion

Analysis of accumulation of 99mTc-octreotide and 99mTc-EDDA/HYNIC-Tyr3-octreotide in the rat kidneys.

Science.gov (United States)

Kopecky, Martin; Semecky, Vladimir; Trejtnar, Frantisek; Laznicek, Milan; Laznickova, Alice; Nachtigal, Petr; Decristoforo, Clemens; Mather, Stephen J; Mäcke, Helmut R

2004-02-01

The aim of this study was to compare renal handling and distribution of (99m)Tc-octreotide and (99m)Tc-EDDA/HYNIC-Tyr(3)-octreotide (HYNIC-TOC) in rats. In kidney perfusion experiments, the renal clearance value of (99m)Tc-octreotide was three times lower than that of (99m)Tc-EDDA/HYNIC-TOC. The predominant renal excretion of (99m)Tc-EDDA/HYNIC-TOC was associated with a high and long-term renal accumulation up to 48 hrs. Microautoradiographic results indicated that (99m)Tc-EDDA/HYNIC-TOC was retained mainly in the renal medulla within the cells of the collecting ducts and in the surrounding tissue. Lower positivity was found in the proximal and distal tubular cells. We conclude that the mechanism of renal accumulation of somatostatin analogues renal accumulation is complex and that proximal tubular reabsorption is probably not the main mechanism for uptake of (99m)Tc-EDDA/HYNIC-TOC in the kidneys. The presence of the somatostatin receptors, differences in the tonicity level within kidneys and other possible mechanisms could participate in their renal accumulation.

Analysis of accumulation of 99mTc-octreotide and 99mTc-EDDA/HYNIC-Tyr3-octreotide in the rat kidneys

International Nuclear Information System (INIS)

Kopecky, Martin; Semecky, Vladimir; Trejtnar, Frantisek; Laznicek, Milan; Laznickova, Alice; Nachtigal, Petr; Decristoforo, Clemens; Mather, Stephen J.; Maecke, Helmut R.

2004-01-01

The aim of this study was to compare renal handling and distribution of 99m Tc-octreotide and 99m Tc-EDDA/HYNIC-Tyr 3 -octreotide (HYNIC-TOC) in rats. In kidney perfusion experiments, the renal clearance value of 99m Tc-octreotide was three times lower than that of 99m Tc-EDDA/HYNIC-TOC. The predominant renal excretion of 99m Tc-EDDA/HYNIC-TOC was associated with a high and long-term renal accumulation up to 48 hrs. Microautoradiographic results indicated that 99m Tc-EDDA/HYNIC-TOC was retained mainly in the renal medulla within the cells of the collecting ducts and in the surrounding tissue. Lower positivity was found in the proximal and distal tubular cells. We conclude that the mechanism of renal accumulation of somatostatin analogues renal accumulation is complex and that proximal tubular reabsorption is probably not the main mechanism for uptake of 99m Tc-EDDA/HYNIC-TOC in the kidneys. The presence of the somatostatin receptors, differences in the tonicity level within kidneys and other possible mechanisms could participate in their renal accumulation

Cystinuria in the maned wolf of South America.

Science.gov (United States)

Bovée, K C; Bush, M; Dietz, J; Jezyk, P; Segal, S

1981-05-22

Of 42 maned wolves in zoos or live-trapped in Brazil, 34 had excessive cystine in their urine. Renal clearance studies of five of the affected wolves revealed a variable defect for the reabsorption of cystine and dibasic amino acids. The renal tubular handling of other solutes including glucose, phosphate, sodium, potassium, and uric acid was considered normal. Urinary calculi composed of cystine were found in four wolves and proved fatal in three of them. With the exception of the high incidence in this species, this hereditary disease resembles the disorder described in dogs and humans.

Hypophosphatemic osteomalacia in von Recklinghausen neurofibromatosis: Case report and literature review

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Aman Gupta

2015-01-01

Full Text Available Osteomalacia in neurofibromatosis is a rare entity and distinct from more common dysplastic skeletal affections of this disease. As a rule, it is characterized by later onset in adulthood. There is renal phosphate loss with hypophosphatemia and multiple pseudofractures in the typical cases. The hypophosphatemic conditions that interfere in bone mineralization comprise many hereditary or acquired diseases, all of them sharing the same pathophysiological mechanism-reduction in phosphate reabsorption by the renal tubuli. This process leads to chronic hyperphosphaturia and hypophosphatemia, associated with inappropriately normal or low levels of calcitriol, causing rickets in children and osteomalacia in adults.

Predictors of renal recovery in patients with pre-orthotopic liver transplant (OLT) renal dysfunction.

Science.gov (United States)

Iglesias, Jose; Frank, Elliot; Mehandru, Sushil; Davis, John M; Levine, Jerrold S

2013-07-13

Renal dysfunction occurs commonly in patients awaiting orthotopic liver transplantation (OLT) for end-stage liver disease. The use of simultaneous liver-kidney transplantation has increased in the MELD scoring era. As patients may recover renal function after OLT, identifying factors predictive of renal recovery is a critical issue, especially given the scarcity of available organs. Employing the UNOS database, we sought to identify donor- and patient-related predictors of renal recovery among 1720 patients with pre-OLT renal dysfunction and transplanted from 1989 to 2005. Recovery of renal function post-OLT was defined as a composite endpoint of serum creatinine (SCr) ≤1.5 mg/dL at discharge and survival ≥29 days. Pre-OLT renal dysfunction was defined as any of the following: SCr ≥2 mg/dL at any time while awaiting OLT or need for renal replacement therapy (RRT) at the time of registration and/or OLT. Independent predictors of recovery of renal function post-OLT were absence of hepatic allograft dysfunction, transplantation during MELD era, recipient female sex, decreased donor age, decreased recipient ALT at time of OLT, decreased recipient body mass index at registration, use of anti-thymocyte globulin as induction therapy, and longer wait time from registration. Contrary to popular belief, a requirement for RRT, even for prolonged periods in excess of 8 weeks, was not an independent predictor of failure to recover renal function post-OLT. These data indicate that the duration of renal dysfunction, even among those requiring RRT, is a poor way to discriminate reversible from irreversible renal dysfunction.

Evaluation of plasma concentrations of homocysteine, IL-6, TNF-alpha, hs-CRP, and total antioxidant capacity in patients with end-stage renal failure.

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Mahin Babaei

2014-12-01

Full Text Available It has been proved that hyperhomocysteinemia has a high prevalence in patients with end-stage renal disease (ESRD, which may contribute to the high cardiovascular risk in these patients. Cardiovascular disease is the first cause of high mortality rate in ESRD patients. The aim of the present study was to assess five important factors in patients with ESRD (the amount of homocysteine, IL-6, TNF-alpha, hs-CRP, and Total Antioxidant Capacity. These factors were surveyed in ESRD patients to compare with healthy subjects. In a cross-sectional study, we enrolled 80 patients on maintenance hemodialysis and measured the inflammatory and oxidative stress indicators. The plasma samples were assayed for five above mentioned variables using standard protocols. Two-hour post hemodialysis plasma samples were also assayed for TAC. Plasma levels of inflammation markers, IL-6 and hs-CRP, homocysteine were significantly increased in ESRD group versus control group. This increase was also found in TNF-α levels as compared to the controls, but the differences were not statistically significant. Also, the post dialysis samples had significantly lower levels of TAC as compared to predialysis ones.

[Immunoglobulin filtration and reabsorption as possible factors in the pathogenesis of chronic glomerulonephritis. Clinical, immunomorphological and histoenzymological research].

Science.gov (United States)

Nabokov, A V; Travkina, E S; Zel'tser, G L; Nevorotin, A I

1992-01-01

Kidney biopsy specimens obtained from a group of individuals with chronic glomerulonephritis (CGN) have been processed for light and electron microscopic immunolocalization of total immunoglobulins (Igs). In a few cases, acid phosphatase (ACPase), a lysosomal enzyme marker, was ultrastructurally visualized. In the glomeruli, horseradish peroxidase-stained Igs were revealed in capillary lumina, urinary spaces and in transit through occasional loci of the glomerular basal membranes while ACPase-containing lysosomes resided both within and outside the cells. In the proximal tubules, Igs were traced in the endocytic vesicles and vacuoles, the latter also being positive for ACPase. Statistically significant relationships have been revealed between the number of IGs-labeled proximal tubules and some clinical or pathomorphological stigmata of CGN, in particular, proteinuria and arterial hypertension levels, marked interstitial sclerosis, etc. The data obtained are discussed in regard to the mechanisms of increased macromolecular filtration and the different proteinuria selectivity levels as well as the development of interstitial sclerosis as a result of the elevated reabsorption and incomplete lysosomal degradation of Igs in CGN.

Dynamic renal scintigraphy in aortic disorders

International Nuclear Information System (INIS)

Terae, Satoshi; Itoh, Kazuo; Tsukamoto, Eriko; Nakada, Kunihiro; Fujimori, Kenji; Hashimoto, Masato; Tanabe, Tatsuzo; Furudate, Masayori; Irie, Goro

1986-01-01

Dynamic renal scintigraphy has been reviewed for evaluation of renal arterial involvement in aortic disorders such as arteriosclerosis obliterans, abdominal aortic aneurysm and dissecting aneurysm. As a diagnostic finding and parameters, we used blood perfusion images of both kidneys and relative split renal function index obtained with analysis of the time-activity curves which were generated using a renal region of interest. In the diagnosis of unilateral renal arterial involvement, sensitivity and specificity of blood perfusion images were 100 % (9/9) and 77 % (10/13) and those of relative split renal function index were 78 % (7/9) and 92 % (12/13), respectively. Dynamic renal scintigraphy was useful for evaluating unilateral renal arterial involvement in aortic diseases. However, scintigraphic diagnosis of bilateral renal arterial involvement were difficult. And in a severe case, we could not differentiate renal parenchymal damage due to renovascular involvement from senile renal dysfunction or hypertensive renal disease which is often a cause of aortic disorders. (author)

Renal Function in Hypothyroidism

International Nuclear Information System (INIS)

Khalid, A. S; Ahmed, M.I; Elfaki, H.M; Hassan, N.; Suliman, S. M.

2006-12-01

Background hypothyroidism induces significant changes in the function of organ systems such as the heart, muscles and brain. Renal function is also influenced by thyroid status. Physiological effects include changes in water and electrolyte metabolism, notably hyponatraemia, and reliable alterations of renal hemodynamics, including decrements in renal blood flow, renal plasma flow, glomerular filtration rate (GFR). Objective renal function is profoundly influenced by thyroid status, the purpose of the present study was to determine the relationship between renal function and thyroid status of patients with hypothyroidism. Design and patients in 5 patients with primary hypothyroidism and control group renal functions are measured by serum creatinine and glomerular filtration rate(GFR) using modified in diet renal disease (MDRD) formula. Result in hypothyroidism, mean serum creatinine increased and mean estimated GFR decreased, compared to the control group mean serum creatinine decreased and mean estimated GFR increased. The hypothyroid patients showed elevated serum creatinine levels(>1.1 mg/d1) compared to control group (p value= 000). In patients mean estimated GFR increased in the control group (p value=.002).Conclusion thus the kidney, in addition to the brain, heart and muscle, is an important target of the action of thyroid hormones.(Author)

Perioperative acute renal failure.

LENUS (Irish Health Repository)

Mahon, Padraig

2012-02-03

PURPOSE OF REVIEW: Recent biochemical evidence increasingly implicates inflammatory mechanisms as precipitants of acute renal failure. In this review, we detail some of these pathways together with potential new therapeutic targets. RECENT FINDINGS: Neutrophil gelatinase-associated lipocalin appears to be a sensitive, specific and reliable biomarker of renal injury, which may be predictive of renal outcome in the perioperative setting. For estimation of glomerular filtration rate, cystatin C is superior to creatinine. No drug is definitively effective at preventing postoperative renal failure. Clinical trials of fenoldopam and atrial natriuretic peptide are, at best, equivocal. As with pharmacological preconditioning of the heart, volatile anaesthetic agents appear to offer a protective effect to the subsequently ischaemic kidney. SUMMARY: Although a greatly improved understanding of the pathophysiology of acute renal failure has offered even more therapeutic targets, the maintenance of intravascular euvolaemia and perfusion pressure is most effective at preventing new postoperative acute renal failure. In the future, strategies targeting renal regeneration after injury will use bone marrow-derived stem cells and growth factors such as insulin-like growth factor-1.

Spiral CT in kidney: assumption of renal function by objective evaluation of renal cortical enhancement

International Nuclear Information System (INIS)

Choi, Bo Yoon; Lee, Jong Seok; Lee, Joon Woo; Myung, Jae Sung; Sim, Jung Suk; Seong, Chang Kyu; Kim, Seung Hyup; Choi, Guk Myeong; Chi, Seong Whi

2000-01-01

To correlate the degree of renal cortical enhancement, objectively evaluated by means of spiral CT with the serum level of creatinine, and to determine the extent to which this degree of enhancement may be used to detect renal parenchymal disease. Eighty patients (M:F = 50:30; age + 25-19, (mean 53) years) with available serum level of creatinine who underwent spiral CT between September and October 1999 were included in this study. In fifty patients the findings suggested hepatic or biliary diseases such as hepatoma, biliary cancer, or stone, while in thirty, renal diseases such as cyst, hematoma, or stone appeared to be present. Spiral CT imaging of the cortical phase was obtained at 30-40 seconds after the injection of 120 ml of non-ionic media at a rate of 3 ml/sec. The degree of renal cortical enhancement was calculated by dividing the CT attenuation number of renal cortex at the level of the renal hilum by the CT attenuation number of aorta at the same level. The degree of renal cortical enhancement was compared with the serum level of creatinine, and the degree of renal cortical enhancement in renal parenchymal disease with that of the normal group. Among eighty patients there were five with renal parenchymal disease and 75 with normal renal function. The ratio of the CT attenuation number of renal cortex to that of aorta at the level of the renal hilum ranged between 0.49 and 0.99 (mean, 0.79; standard deviation, 0.15). while the serum level of creatinine ranged between 0.6 and 3.2 mg/dl. There was significant correlation (coefficient of -0.346) and a statistically significant probability of 0.002 between the ratio of the CT attenuation numbers and the serum level of creatinine. There was a significant difference (statistically significant probability of less than 0.01) between those with renal parenchymal disease and the normal group. The use of spiral CT to measure the degree of renal cortical enhancement provides not only an effective index for

The effects of sodium-glucose co-transporter 2 inhibitors in patients with type 2 diabetes

DEFF Research Database (Denmark)

Storgaard, Heidi; Gluud, Lise Lotte; Christensen, Mikkel

2014-01-01

INTRODUCTION: Sodium-glucose co-transporter 2 inhibitors (SGLT-2i) increase urinary glucose excretion through a reduced renal glucose reabsorption. We plan to perform a systematic review of SGLT-2i for treatment of type 2 diabetes. METHODS AND ANALYSIS: A systematic review with meta-analyses of r......INTRODUCTION: Sodium-glucose co-transporter 2 inhibitors (SGLT-2i) increase urinary glucose excretion through a reduced renal glucose reabsorption. We plan to perform a systematic review of SGLT-2i for treatment of type 2 diabetes. METHODS AND ANALYSIS: A systematic review with meta......-analyses of randomised clinical trials on SGLT-2i versus placebo, other oral glucose lowering drugs or insulin for patients with type 2 diabetes will be performed. The primary end point will be the glycated haemoglobin. Secondary end points will include changes in body weight, body mass index, fasting plasma glucose......, plasma cholesterol, kidney and liver blood tests, blood pressure and adverse events. Electronic (the Cochrane Library, MEDLINE, EMBASE and the Science Citation Index) and manual searches will be performed. Meta-analyses will be performed and the results presented as mean differences for continuous...

Studies on the evaluation of renal function in urological renal disorders with 99mTc-DMSA renal uptake, 1

International Nuclear Information System (INIS)

Takeda, Masayuki

1987-01-01

The change of normal value of 99m Tc-dimercaptosuccinic acid (DMSA) renal uptake with age was investigated, and the correlation between total renal uptake of 99m Tc-DMSA and 24-hour endogenous creatinine clearance was studied in each age group separately. (1) 99m Tc-DMSA renal uptake was measured in 107 normal controls without renal or urinary tract diseases between 0 and 67 years old and normal values were analyzed in each age group. The normal value was highest in the age group of 0 ∼ 9 years old and was gradually decreased with age. Over 20 years old, the normal value hardly changed. (2) The lower limit of normal values of 99m Tc-DMSA renal uptake in each kidney was 19.62, 13.89, 13.18, 11.58, 12.00, 10.24 % in the age groups of 0 ∼ 9, 10 ∼ 19, 20 ∼ 29, 30 ∼ 39, 40 ∼ 49, 50 ∼ 59 years old, respectively. (3) Correlations between total renal uptake and 24-hour endogenous creatinine clearance were investigated in each age group in 248 patients between 0 and 79 years old. Positive linear correlations were found in the age groups of 0 ∼ 9, 10 ∼ 19, 20 ∼ 29, 30 ∼ 39, 40 ∼ 49, 50 ∼ 59, 60 ∼ 69, 70 ∼ 79 years old, and especially above 50 years old closer correlations were found. It is concluded that although 99m Tc-DMSA renal uptake is a useful method for renal function test through life, the change with age must be considered in the evaluation of its value. (author)

Eppur Si Muove: The dynamic nature of physiological control of renal blood flow by the renal sympathetic nerves.

Science.gov (United States)

Schiller, Alicia M; Pellegrino, Peter Ricci; Zucker, Irving H

2017-05-01

Tubuloglomerular feedback and the myogenic response are widely appreciated as important regulators of renal blood flow, but the role of the sympathetic nervous system in physiological renal blood flow control remains controversial. Where classic studies using static measures of renal blood flow failed, dynamic approaches have succeeded in demonstrating sympathetic control of renal blood flow under normal physiological conditions. This review focuses on transfer function analysis of renal pressure-flow, which leverages the physical relationship between blood pressure and flow to assess the underlying vascular control mechanisms. Studies using this approach indicate that the renal nerves are important in the rapid regulation of the renal vasculature. Animals with intact renal innervation show a sympathetic signature in the frequency range associated with sympathetic vasomotion that is eliminated by renal denervation. In conscious rabbits, this sympathetic signature exerts vasoconstrictive, baroreflex control of renal vascular conductance, matching well with the rhythmic, baroreflex-influenced control of renal sympathetic nerve activity and complementing findings from other studies employing dynamic approaches to study renal sympathetic vascular control. In this light, classic studies reporting that nerve stimulation and renal denervation do not affect static measures of renal blood flow provide evidence for the strength of renal autoregulation rather than evidence against physiological renal sympathetic control of renal blood flow. Thus, alongside tubuloglomerular feedback and the myogenic response, renal sympathetic outflow should be considered an important physiological regulator of renal blood flow. Clinically, renal sympathetic vasomotion may be important for solving the problems facing the field of therapeutic renal denervation. Copyright © 2016 Elsevier B.V. All rights reserved.

Leiomyosarcoma of the renal pelvis

Directory of Open Access Journals (Sweden)

Dhamne Sagar

2009-10-01

Full Text Available Leiomyosarcomas are rare malignant tumors of the kidney. They may arise from the renal capsule, renal vein, renal pelvic musculature or renal parenchyma. Renal pelvis is an uncommon site of occurrence, with around 10 cases reported in the literature so far. Here we present a 60-year-old male who presented with increased urinary frequency, lower limb weakness, anorexia and weight loss. Imaging showed a right renal mass. A renal cell carcinoma was suspected clinically. A right nephrectomy was performed, which showed a large circumscribed mass in the hilar region. Histology revealed a tumor mass arising from the renal pelvis. The tumor was composed of spindle cells arranged in fascicles. Immunohistochemistry showed tumor cells to be positive for smooth muscle actin (SMA and desmin (Des and negative for cytokeratin (CK, HMB 45, CD117 (C-kit, and CD34. That confirmed the diagnosis of leiomyosarcoma.

Renal and post-renal causes of acute renal failure in children

International Nuclear Information System (INIS)

Jamal, A.; Ramzan, A.

2004-01-01

Objective: To identify the causes of acute renal failure (ARF) in pediatric population along with the identification of the age and gender most affected by the failure. Subjects and Methods: The study included children under the age of 12 years who presented with signs and symptoms suggestive of ARF (oliguria/anuria, vomiting, acidotic breathing etc.) along with raised blood urea nitrogen (BUN) serum creatinine and metabolic acidosis as shown by arterial blood gases (ABGs). Patients were divided into two group on the basis of age; group A consisting of 0-2 years and group B from >2 years. Patients presenting with transient pre-renal azotaemia were excluded from the study. After providing initial emergency cover, detailed history, physical examination and investigations were carried out according to a proforma specially designed to ascertain the cause of ARF. Patients were managed for ARF as per standard recommendations and investigations completed or repeated as and when required. Results: A total of 119 patients with ARF were admitted in the ward over a period of two years constituting 1.36% of the total admissions and 16.39% of the admissions due to renal pathology. Mean age of presentation was 4.5 years 16.7% of the patients under the age of 5 years. Male predominance was noted in all ages with an overall male to female ratio of 2.3:1. Most common cause leading to ARF in younger age group was found to be hemolytic uremic syndrome [25(54.34%)] followed by septicemia [7(15.21 %)]. In older patients renal calculus disease was the most common [22(30.13%)] underlying pathology followed by pre-existing, undiagnosed chronic renal failure [16(21.91 %)]. Conclusion: ARF is fairly cotton in children especially under the age of 5 years showing a male predominance. More than 90% of the cases can be prevented by improving primary health care and by early and prompt treatment of infections. (author)

Dependence of renal blood flow on renal artery stenosis measured using CT angiography

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Luedemann, Lutz [Charite - Universitaetsmedizin Berlin (Germany). Dept. of Radiotherapy; Nafz, B.; Persson, P. [Charite - Universitaetsmedizin Berlin (Germany). Inst. for Vegetative Physiology; Elsner, F. [Krankenhaus am Urban, Berlin (Germany). Dept. of Anesthesiology; Grosse-Siestrup, C.; Meissler, M. [Charite - Universitaetsmedizin Berlin (Germany). Experimental Animal Unit; Gutberlet, M. [Charite - Universitaetsmedizin Berlin (Germany). Dept. of Diagnostic and Interventional Radiology; Univ. Leipzig/ Leipzig Heart Center (Germany). Dept. of Diagnostic and Interventional Radiology; Lengsfeld, P.; Voth, M. [Bayer-Schering Pharma AG, Berlin (Germany). Global Medical Affairs Diagnostic Imaging

2011-03-15

The present study investigates the suitability of computed tomography angiography (CTA) depicting the degree of renal artery stenosis for estimating renal blood flow (RBF) in a kidney. Materials and Methods: We investigated renal artery stenosis assessment by CTA in eight adult female hybrid pigs with an ultrasound probe implanted at the renal vein for RBF measurement. An inflatable metal-free cuff was placed around the renal artery to control the RBF. The RBF was then reduced in four steps. For each reduced RBF value and baseline RBF, CTA with a reconstructed slice thickness of 0.625 mm was performed in the arterial phase following injection of 80 ml of nonionic intravenous contrast medium. The radius of the stenotic and non-stenotic renal artery segment was measured in the reconstructed images. Results: A significant linear correlation (p < 0.0001) was found between the relative apparent stenosis (calculated as the ratio of the radii of the actual stenotic segment and a non-stenotic renal artery segment) and RBF. The linear regression yielded a slope of 0.57 and a y-axis of 24.1 %. A significant linear correlation (p < 0.0001) was also found between the relative true stenosis (the ratio of the radii of the actual stenotic segment and a non-stenotic renal artery segment at baseline) and the RBF. The linear regression yielded a slope of 0.67 and a y-axis of 13.8 %. Conclusion: The results show that the relative stenosis apparent on CTA differs from the true degree of renal artery stenosis. Nevertheless, the degree of renal artery stenosis determined by CTA provides a reliable estimate of the resulting RBF reduction. (orig.)

Dependence of renal blood flow on renal artery stenosis measured using CT angiography

International Nuclear Information System (INIS)

Luedemann, Lutz; Nafz, B.; Persson, P.; Elsner, F.; Grosse-Siestrup, C.; Meissler, M.; Gutberlet, M.; Univ. Leipzig/ Leipzig Heart Center; Lengsfeld, P.; Voth, M.

2011-01-01

The present study investigates the suitability of computed tomography angiography (CTA) depicting the degree of renal artery stenosis for estimating renal blood flow (RBF) in a kidney. Materials and Methods: We investigated renal artery stenosis assessment by CTA in eight adult female hybrid pigs with an ultrasound probe implanted at the renal vein for RBF measurement. An inflatable metal-free cuff was placed around the renal artery to control the RBF. The RBF was then reduced in four steps. For each reduced RBF value and baseline RBF, CTA with a reconstructed slice thickness of 0.625 mm was performed in the arterial phase following injection of 80 ml of nonionic intravenous contrast medium. The radius of the stenotic and non-stenotic renal artery segment was measured in the reconstructed images. Results: A significant linear correlation (p < 0.0001) was found between the relative apparent stenosis (calculated as the ratio of the radii of the actual stenotic segment and a non-stenotic renal artery segment) and RBF. The linear regression yielded a slope of 0.57 and a y-axis of 24.1 %. A significant linear correlation (p < 0.0001) was also found between the relative true stenosis (the ratio of the radii of the actual stenotic segment and a non-stenotic renal artery segment at baseline) and the RBF. The linear regression yielded a slope of 0.67 and a y-axis of 13.8 %. Conclusion: The results show that the relative stenosis apparent on CTA differs from the true degree of renal artery stenosis. Nevertheless, the degree of renal artery stenosis determined by CTA provides a reliable estimate of the resulting RBF reduction. (orig.)

Acute renal dysfunction in liver diseases

OpenAIRE

Betrosian, Alex P; Agarwal, Banwari; Douzinas, Emmanuel E

2007-01-01

Renal dysfunction is common in liver diseases, either as part of multiorgan involvement in acute illness or secondary to advanced liver disease. The presence of renal impairment in both groups is a poor prognostic indicator. Renal failure is often multifactorial and can present as pre-renal or intrinsic renal dysfunction. Obstructive or post renal dysfunction only rarely complicates liver disease. Hepatorenal syndrome (HRS) is a unique form of renal failure associated with advanced liver dise...

Assessment of renal function with 99Tcm-DTPA renal dynamic imaging in neonatal hydronephrosis

International Nuclear Information System (INIS)

Jiang Lixin; Guo Zongyuan; Wu Rongde; Yu Qihai; Liu Zhanfeng

2004-01-01

Objective: To assess the renal function in neonatal hydronephrosis with 99 Tc m -DTPA renal imaging. Methods: Eighteen unilateral hydronephrotic kidneys and 12 normal kidneys were studied by 99 Tc m -DTPA renal dynamic imaging , and glomerular filtration rate (GFR) quantitative analysis was also performed. Blood urea nitrogen (BUN), serum creatinine (SCr) and hemoglobin (Hb) were determined simultaneously and the correlations between GFR and each of these parameters were analyzed. Results: Positive correlation was discovered between GFR and Hb in neonates with moderate or severe hydronephrosis (r=0.414, 0.667, P 0.05). The renal function was decreased significantly in moderate and severe neonatal hydronephrosis (P 99 Tc m -DTPA renal dynamic imaging GFR is an ideal marker for estimating renal function in neonatal hydronephrosis; SCr could be a marker for renal damage especially in moderate and severe neonatal hydronephrosis; BUN could not be a marker for evaluating renal function in neonatal hydronephrosis. Neonates with hydronephrosis should be referred for surgical procedures as soon as possible in the early stage

Development and preclinical characterisation of 99mTc-labelled Affibody molecules with reduced renal uptake

International Nuclear Information System (INIS)

Ekblad, Torun; Karlstroem, Amelie Eriksson; Tran, Thuy; Orlova, Anna; Feldwisch, Joachim; Widstroem, Charles; Abrahmsen, Lars; Wennborg, Anders; Tolmachev, Vladimir

2008-01-01

Affibody molecules are low molecular weight proteins (7 kDa), which can be selected to bind to tumour-associated target proteins with subnanomolar affinity. Because of rapid tumour localisation and clearance from nonspecific compartments, Affibody molecules are promising tracers for molecular imaging. Earlier, 99m Tc-labelled Affibody molecules demonstrated specific targeting of tumour xenografts. However, the biodistribution was suboptimal either because of hepatobiliary excretion or high renal uptake of the radioactivity. The goal of this study was to optimise the biodistribution of Affibody molecules by chelator engineering. Anti-HER2 Z HER2:342 Affibody molecules, carrying the mercaptoacetyl-glutamyl-seryl-glutamyl (maESE), mercaptoacetyl-glutamyl-glutamyl-seryl (maEES) and mercaptoacetyl-seryl-glutamyl-glutamyl (maSEE) chelators, were prepared by peptide synthesis and labelled with 99m Tc. The tumour-targeting capacity of these conjugates was compared with each other and with the best previously available conjugate, 99m Tc-maEEE-Z HER2:342, in nude mice bearing SKOV-3 xenografts. The tumour-targeting capacity of the most promising conjugate, 99m Tc-maESE-Z HER2:342, was compared with radioiodinated Z HER2:342 . All novel conjugates demonstrated successful tumour targeting and a low degree of hepatobiliary excretion. The renal uptakes of serine-containing conjugates, 33±5, 68±21 and 71±10%IA/g, for 99m Tc-maESE-Z HER2:342 , 99m Tc-maEES-Z HER2:342 and 99m Tc-maSEE-Z HER2:342 , respectively, were significantly reduced in comparison with 99m Tc-maEEE-Z HER2:342 (102 ± 13%IA/g). For 99m Tc-maESE-Z HER2:342 , a tumour uptake of 9.6±1.8%IA/g and a tumour-to-blood ratio of 58±6 were reached at 4 h p.i. A combination of serine and glutamic acid residues in the chelator sequence confers increased renal excretion and relatively low renal uptake of 99m Tc-labelled Affibody molecules. In combination with preserved targeting capacity, this improved imaging of targets

Renal Function Outcomes for Multifocal Renal Neoplasms Managed by Radiofrequency Ablation

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Gupta, Pushpender, E-mail: pugupta@wakehealth.edu; Allen, Brian C., E-mail: bcallen2@wakehealth.edu; Chen, Michael Y., E-mail: mchen@wakehealth.edu; Childs, David D., E-mail: dchilds@wakehealth.edu; Kota, Gopi, E-mail: gkota@wakehealth.edu; Zagoria, Ronald J., E-mail: rzagoria@wakehealth.edu [Wake Forest University School of Medicine, Department of Radiology (United States)

2013-10-15

Purpose: To evaluate renal function changes related to radiofrequency ablation (RFA) for the treatment of multifocal renal neoplasms. Methods: This is an institutional review board-approved, Health Insurance Portability and Accountability Act compliant retrospective study of all patients treated with computed tomography guided RFA for multifocal renal neoplasms at one institution. Fifty-seven subjects, mean age 70 (range 37-88) years, underwent RFA of 169 renal neoplasms (average size 2.0 cm). Subjects had between 2 and 8 (mean 2.96) neoplasms ablated. Estimated glomerular filtration rate (eGFR) was measured before and after RFA. Complications related to RFA were recorded. Results: eGFR decreased on average of 4.4 % per tumor treated and 6.7 % per ablation session (average 1.76 tumors treated per session). For subjects with the largest neoplasm measuring >3 cm, eGFR decreased an average of 14.5 % during the course of their treatment. If the largest neoplasm measured 2-3 cm, eGFR decreased an average of 7.7 %, and if the largest neoplasm measured <2 cm, eGFR decreased an average of 3.8 %. Subjects with reduced baseline renal function were more likely to have a greater decline in eGFR after RFA. There was a minor complication rate of 6.3 % (6 of 96 sessions), none of which required treatment, and a major complication rate of 4.2 % (4 of 96 sessions). Conclusion: RFA for the treatment of multifocal renal neoplasms results in mild decline of renal function.

Renal papillary necrosis

Science.gov (United States)

... asking your provider. Alternative Names Necrosis - renal papillae; Renal medullary necrosis Images Kidney anatomy Kidney - blood and urine flow References Bushinsky DA, Monk RD. Nephrolithiasis and nephrocalcinosis. ...

Imaging of renal osteodystrophy

Energy Technology Data Exchange (ETDEWEB)

Jevtic, V. E-mail: vladimir.jevtic@mf.uni-lj.si

2003-05-01

Chronic renal insufficiency, hemodialysis, peritoneal dialysis, renal transplantation and administration of different medications provoke complex biochemical disturbances of the calcium-phosphate metabolism with wide spectrum of bone and soft tissue abnormalities termed renal osteodystrophy. Clinically most important manifestation of renal bone disease includes secondary hyperparathyroidism, osteomalacia/rickets, osteoporosis, adynamic bone disease and soft tissue calcification. As a complication of long-term hemodialysis and renal transplantation amyloid deposition, destructive spondyloarthropathy, osteonecrosis, and musculoskeletal infections may occur. Due to more sophisticated diagnostic methods and more efficient treatment classical radiographic features of secondary hyperparathyroidism and osteomalacia/rickets are now less frequently seen. Radiological investigations play an important role in early diagnosis and follow-up of the renal bone disease. Although numerous new imaging modalities have been introduced in clinical practice (scintigraphy, CT, MRI, quantitative imaging), plain film radiography, especially fine quality hand radiograph, still represents most widely used examination.

Imaging of renal osteodystrophy

International Nuclear Information System (INIS)

Jevtic, V.

2003-01-01

Chronic renal insufficiency, hemodialysis, peritoneal dialysis, renal transplantation and administration of different medications provoke complex biochemical disturbances of the calcium-phosphate metabolism with wide spectrum of bone and soft tissue abnormalities termed renal osteodystrophy. Clinically most important manifestation of renal bone disease includes secondary hyperparathyroidism, osteomalacia/rickets, osteoporosis, adynamic bone disease and soft tissue calcification. As a complication of long-term hemodialysis and renal transplantation amyloid deposition, destructive spondyloarthropathy, osteonecrosis, and musculoskeletal infections may occur. Due to more sophisticated diagnostic methods and more efficient treatment classical radiographic features of secondary hyperparathyroidism and osteomalacia/rickets are now less frequently seen. Radiological investigations play an important role in early diagnosis and follow-up of the renal bone disease. Although numerous new imaging modalities have been introduced in clinical practice (scintigraphy, CT, MRI, quantitative imaging), plain film radiography, especially fine quality hand radiograph, still represents most widely used examination

CT findings of renal abscess

International Nuclear Information System (INIS)

Lee, Myung Jun; Kim, Mi Young; Woo, Jung Ju; Kim, Ho Kyun; Kim, Won Hong; Jeon, Jeong Dong; Jeon, Woo Ki; Han, Chang Yul

1996-01-01

The purpose of this study is to determine characteristic CT findings in renal abscess. Twenty cases of renal abscess were retrospectively analyzed for CT findings relating to the shape and extent of the abscess, change of nephrogram, peripheral rim enhancement, wedge-shaped enhancement on delayed scans, enlargement of the kidney involved and associated findings. Seven patients had a renal abscess at the right kidney, nine at the lift kidney and two bilaterally. The abscesses were round in 18 cases and finger-like in two. Rim enhancement around renal abscess was seen in four cases (20%). Changes in the nephrogram around the abscess were seen in 12 cases (60%). In all six patients who had undergone delayed postcontrast scans, wedge-shaped enhancement was shown around the abscess (100%). In the observation of the extent of renal abscesses, 14 cases were within the kidney, six cases extended the beyond renal capsule, and two were loculated in the renal fascia itself. Renal enlargement was seen in nine cases (45%). These results suggest that CT findings such as delayed wedge-shaped enhancement, change of nephrogram, peripheral rim enhancement, renal enlargement, and associated findings are valuable for diagnosis, and that CT also gives information concerning the extent, evolution and complication of a renal abscess

[Clinical study of influential factors on renal scarring after ESWL monotherapy for renal stone disease].

Science.gov (United States)

Ishito, Noritaka; Takamoto, Hitoshi; Kunitomi, Kimito; Satoh, Eiichi; Ishii, Ayano; Shiotuka, Youichi; Sako, Shinichi; Ohta, Naoki; Araki, Tohru

2002-11-01

ESWL is now widely used for the treatment of renal stone disease. Although ESWL has many advantages for patients' quality of life, few reports have demonstrated the long-term outcomes of the alterations of renal morphology after ESWL. We reported renal scarring after ESWL monotherapy in patients with renal calyceal stones. In this study, we evaluated a large series of patients' cohort treated at our institution, and assessed the causal effect of ESWL on the late occurrence of renal scar formation. ESWL was performed with EDAP (LT-01,02) that generates shock wave energy by piezoelectric discharge. We analyzed the records of 285 kidneys treated between Dec. 1986 and Nov. 1998. Renal scarring was noted in 44 kidneys and not in 241 kidneys with periodical ultrasonography. We compared the backgrounds of the two groups using chi-square or non-parametric analysis. The Kaplan-Meier method and Cox regression model determined the analysis of renal scar formation. Univariate and multiple regression analysis revealed that the total amount of ESWL emission and hyperuricemia independently affected the probability of renal scar formation. Over-emission of ESWL (over 10,000 shots) must be care for the prevention of renal scarring in patients with renal calyceal calculi, especially when associated with hyperuricemia. After ESWL, periodical checkups with ultrasonography will provide useful information for the clinical diagnosis of renal scarring.

Análise renal de ultramaratonista em prova de 75 km Análisis renal de corredora en la prueba de 75 kilómetros Renal analysis in 75 km ultra-marathon participants

Directory of Open Access Journals (Sweden)

Thiago Ribeiro Lopes

2009-01-01

Full Text Available OBJETIVO: Identificar alterações urinárias compatíveis com comprometimento renal em ultramaratonista e "pacer" (ciclista de apoio ao longo de uma prova de 75 quilômetros. MÉTODOS: Para tal, utilizou-se teste de urina com fita reagente em quatro tempos diferentes, além de avaliação antropométrica. RESULTADOS: As medidas concernentes a ultramaratonista a classificaram como eutrófica, assim como o "pacer". Observou-se, assim, associação entre os momentos de esforço físico máximo e a detecção de alterações urinárias, definidas pela presença de hematúria e, por vezes, positivação da proteinúria. CONCLUSÃO: Foi possível ilustrar alteração transitória em dois indivíduos saudáveis submetidos a exercício intenso.OBJETIVO: Identificar alteraciones urinarias compatibles con compromiso renal en una corredora y un "pacer" (ciclista de apoyo a lo largo de una prueba de 75 Kilómetros. MÉTODOS: Para tal efecto, se utilizó un test de orina con cinta reactiva aplicado en cuatro tiempos diferentes, además de una evaluación antropométrica. RESULTADOS: Las medidas concernientes a la corredora la clasificaron como eutrófica, así como el "pacer". Se observó que existe asociación entre los momentos de esfuerzo físico máximo y la detección de alteraciones urinarias, definidas por la presencia de hematuria y, a veces, proteinuria. CONCLUSIÓN: Fue posible demostrar la alteración transitoria en dos individuos saludables sometidos a ejercicio intenso.OBJECTIVE: To identify urinary abnormalities, indicative of renal involvement, in 75 km ultra-marathon racer and pacer (cyclist that gives support to the racer. METHODS: Renal analysis consisted of urine dipstick tests in four different times and anthropometric measures. RESULTS: Both the racer and the pacer were in eutrophic conditions. There was an association between the capacity for maximum physical effort and detection of urinary abnormalities determined by the presence of

Acute renal haemodynamic and renin-angiotensin system responses to graded renal artery stenosis in the dog.

Science.gov (United States)

Anderson, W P; Johnston, C I; Korner, P I

1979-01-01

1. The acute renal haemodynamic and renin-angiotensin system responses to graded renal artery stenosis were studied in chronically instrumented, unanaesthetized dogs. 2. Stenosis was induced over 30 sec by inflation of a cuff around the renal artery to lower distal pressure to 60, 40 or 20 mmHg, with stenosis maintained for 1 hr. This resulted in an immediate fall in renal vascular resistance, but over the next 5--30 min both resistance and renal artery pressure were restored back towards prestenosis values. Only transient increases in systemic arterial blood pressure and plasma renin and angiotensin levels were seen with the two milder stenoses. Despite restoration of renal artery pressure, renal blood flow remained reduced at all grades of stenosis. 3. Pre-treatment with angiotensin I converting enzyme inhibitor or sarosine1, isoleucone8 angiotensin II greatly attenuated or abolished the restoration of renal artery pressure and renal vascular resistance after stenosis, and plasma renin and angiotensin II levels remained high. Renal dilatation was indefinitely maintained, but the normal restoration of resistance and pressure could be simulated by infusing angiotensin II into the renal artery. 4. The effective resistance to blood flow by the stenosis did not remain constant but varied with changes in the renal vascular resistance. PMID:219182

Value of renal cortical thickness as a predictor of renal function impairment in chronic renal disease patients

Directory of Open Access Journals (Sweden)

Samia Rafael Yamashita

2015-02-01

Full Text Available Objective: To determine the presence of linear relationship between renal cortical thickness, bipolar length, and parenchymal thickness in chronic kidney disease patients presenting with different estimated glomerular filtration rates (GFRs and to assess the reproducibility of these measurements using ultrasonography. Materials and Methods: Ultrasonography was performed in 54 chronic renal failure patients. The scans were performed by two independent and blinded radiologists. The estimated GFR was calculated using the Cockcroft-Gault equation. Interobserver agreement was calculated and a linear correlation coefficient (r was determined in order to establish the relationship between the different renal measurements and estimated GFR. Results: The correlation between GFR and measurements of renal cortical thickness, bipolar length, and parenchymal thickness was, respectively, moderate (r = 0.478; p < 0.001, poor (r = 0.380; p = 0.004, and poor (r = 0.277; p = 0.116. The interobserver agreement was considered excellent (0.754 for measurements of cortical thickness and bipolar length (0.833, and satisfactory for parenchymal thickness (0.523. Conclusion: The interobserver reproducibility for renal measurements obtained was good. A moderate correlation was observed between estimated GFR and cortical thickness, but bipolar length and parenchymal thickness were poorly correlated.

Cadmium and renal cancer

International Nuclear Information System (INIS)

Il'yasova, Dora; Schwartz, Gary G.

2005-01-01

Background: Rates of renal cancer have increased steadily during the past two decades, and these increases are not explicable solely by advances in imaging modalities. Cadmium, a widespread environmental pollutant, is a carcinogen that accumulates in the kidney cortex and is a cause of end-stage renal disease. Several observations suggest that cadmium may be a cause of renal cancer. Methods: We performed a systematic review of the literature on cadmium and renal cancer using MEDLINE for the years 1966-2003. We reviewed seven epidemiological and eleven clinical studies. Results: Despite different methodologies, three large epidemiologic studies indicate that occupational exposure to cadmium is associated with increased risk renal cancer, with odds ratios varying from 1.2 to 5.0. Six of seven studies that compared the cadmium content of kidneys from patients with kidney cancer to that of patients without kidney cancer found lower concentrations of cadmium in renal cancer tissues. Conclusions: Exposure to cadmium appears to be associated with renal cancer, although this conclusion is tempered by the inability of studies to assess cumulative cadmium exposure from all sources including smoking and diet. The paradoxical findings of lower cadmium content in kidney tissues from patients with renal cancer may be caused by dilution of cadmium in rapidly dividing cells. This and other methodological problems limit the interpretation of studies of cadmium in clinical samples. Whether cadmium is a cause of renal cancer may be answered more definitively by future studies that employ biomarkers of cadmium exposure, such as cadmium levels in blood and urine

Renal endothelial function and blood flow predict the individual susceptibility to adriamycin-induced renal damage

NARCIS (Netherlands)

Ochodnicky, Peter; Henning, Robert H.; Buikema, Hendrik; Kluppel, Alex C. A.; van Wattum, Marjolein; de Zeeuw, Dick; van Dokkum, Richard P. E.

2009-01-01

Susceptibility to renal injury varies among individuals. Previously, we found that individual endothelial function of healthy renal arteries in vitro predicted severity of renal damage after 5/6 nephrectomy. Here we hypothesized that individual differences in endothelial function in vitro and renal

[Hypertension and renal disease

DEFF Research Database (Denmark)

Kamper, A.L.; Pedersen, E.B.; Strandgaard, S.

2009-01-01

Renal mechanisms, in particular the renin-angiotensin system and renal salt handling, are of major importance in blood pressure regulation. Co-existence of hypertension and decreased renal function may be due to nephrosclerosis secondary to hypertension, or primary renal disease with secondary...... hypertension. Mild degrees of chronic kidney disease (CKD) can be detected in around 10% of the population, and detection is important as CKD is an important risk factor for atherosclerotic cardiovascular disease. Conversely, heart failure may cause an impairment of renal function. In chronic progressive...... nephropathy, effective blood pressure lowering is of paramount importance, and angiotensin converting enzyme inhibitors and angiotensin receptor blockers are agents of choice Udgivelsesdato: 2009/6/15...

Bilateral triple renal arteries

International Nuclear Information System (INIS)

Pestemalci, Turan; Yildiz, Yusuf Zeki; Yildirim, Mehmet; Mavi, Ayfer; Gumusburun, Erdem

2009-01-01

Knowledge of the variations of the renal artery has grown in importance with increasing numbers of renal transplants, vascular reconstructions and various surgical and radio logic techniques being performed in recent years. We report the presence of bilateral triple renal arteries, discovered on routine dissection of a male cadaver. On the right side, one additional renal artery originated from the abdominal aorta (distributed to superior pole of the kidney) and one other originated from the right common iliac artery (distributed to lower pole of the kidney). On the left side, both additional renal arteries originated from the abdominal aorta. Our observation has been compared with variations described in the literature and their clinical importance has been emphasized. (author)

Radiology of renal failure

International Nuclear Information System (INIS)

Griffiths, H.J.

1990-01-01

This book covers most aspects of imaging studies in patients with renal failure. The initial chapter provides basic information on contrast agents, intravenous urography, and imaging findings in the urinary tract disorders responsible for renal failure and in patients who have undergone transplantation. It illustrates common gastro-intestinal abnormalities seen on barium studies in patients with renal failure. It illustrates the cardiopulmonary complications of renal failure and offers advice for radiologic differentiation. It details different aspects of skeletal changes in renal failure, including a basic description of the pathophysiology of the changes; many excellent illustrations of classic bone changes, arthritis, avascular necrosis, and soft-tissue calcifications; and details of bone mineral analysis

The cell engineering construction and function evaluation of multi-layer biochip dialyzer.

Science.gov (United States)

Zhu, Wen; Li, Jiwei; Liu, Jianfeng

2013-10-01

We report the fabrication and function evaluation of multi-layer biochip dialyzer. Such device may potentially be applied to the wearable hemodialysis systems. By merging the advantages of microfluidic chip technology with cell engineering, both functions of glomerular filtration and renal tubule physiological activity are integrated in the same device. This device is designed into a laminated structure, in which the chip number of the superimposed layer can be arbitrarily tailored in accordance with the requirements of dialysis capacity. We propose that such structure can overcome the obstacles of large size and detached structure of the traditional hollow fiber dialyzer. To construct this multilayer biochips dialyzer, two types of dialyzer device with two-layered and six-layered chips are assembled, respectively. Cell adhesion and proliferation on three different dialysis membrane materials under static and dynamic conditions are investigated and compared. The filtration capability, re-absorption function and excrete ammonia function of the resulting multi-layer biochip dialyzer are evaluated. The results reveal that the constructed device can perform higher filtration efficiency and also play a role of renal tubule. This methodology may be useful in developing "scaling down" artificial kidneys that can act as wearable or even implantable hemodialysis systems.

Renal sinus fat invasion and tumoral thrombosis of the inferior vena cava-renal vein: only confined to renal cell carcinoma.

Science.gov (United States)

Acar, Turker; Harman, Mustafa; Guneyli, Serkan; Sen, Sait; Elmas, Nevra

2014-01-01

Epithelioid angiomyolipoma (E-AML), accounting for 8% of renal angiomyolipoma, is usually associated with tuberous sclerosis (TS) and demonstrates aggressive behavior. E-AML is macroscopically seen as a large infiltrative necrotic tumor with occasional extension into renal vein and/or inferior vena cava. However, without history of TS, renal sinus and venous invasion E-AML would be a challenging diagnosis, which may lead radiologists to misinterpret it as a renal cell carcinoma (RCC). In this case presentation, we aimed to report cross-sectional imaging findings of two cases diagnosed as E-AML and pathological correlation of these aforementioned masses mimicking RCC.

Diagnostic use of angiotensin converting enzyme (ACE)-inhibited renal scintigraphy in the identification of selective renal artery stenosis in the presence of multiple renal arteries: A case report

International Nuclear Information System (INIS)

Morton, K.A.; Rose, S.C.; Haakenstad, A.O.; Handy, J.E.; Scuderi, A.J.; Datz, F.L.

1990-01-01

In patients with renovascular hypertension, it is unknown whether the angiotensin converting enzyme-(ACE) inhibited renal scan will identify stenosis of a segmental branch of a single renal artery or of an accessory artery where multiple renal arteries are present. Since multiple renal arteries may be present in approximately 25% of all individuals, it will be important to establish whether the ACE-inhibited renal scan is useful in this population. We report a case of stenosis involving a renal artery in a patient with multiple renal arteries, successfully identified by ACE-inhibited renal scintigraphy

Renal inflammatory myofibroblastic tumor

DEFF Research Database (Denmark)

Heerwagen, S T; Jensen, C; Bagi, P

2007-01-01

Renal inflammatory myofibroblastic tumor (IMT) is a rare soft-tissue tumor of controversial etiology with a potential for local recurrence after incomplete surgical resection. The radiological findings in renal IMT are not well described. We report two cases in adults with a renal mass treated...

Does complete renal denervation translate into superior clinical outcomes? Lessons learned from denervation of accessory renal arteries

OpenAIRE

Mendelsohn, Farrell O.

2014-01-01

Pre-clinical studies of renal denervation would suggest that the extent of renal nerve injury correlates with outcomes. The “completeness” of renal nerve injury following renal denervation correlates with treatment-based variables such as the depth of ablation, the number of ablations along the length of the artery, and the number of renal arteries successfully ablated. Renal denervation techniques targeting only main renal arteries may lead to suboptimal results in patients with accessory re...

Renal haemodynamic in essential hypertension assessed by 133Xe washout and selective renal angiography

International Nuclear Information System (INIS)

Gatta, A.; Merkel, C.; Pessina, A.C.; Milani, L.; Sacerdoti, D.; Zuin, R.

1982-01-01

The renal and intrarenal haemodynamic pattern in 17 patients with essential hypertension of different severity and duration was studied by means of the 133-Xenon washout technique and the selective renal angiography. The mean and the cortical renal blood flows were on average significantly decreased as compared to the controls. A good agreement was found between the reduction in renal perfusion and the degree of vascular abnormalities as shown by angiography; on the contrary no correlation was found between the impairment in renal blood flow and the degree and/or duration of hypertension

Exaggerated natriuresis and lithium clearance in spontaneously hypertensive rats

DEFF Research Database (Denmark)

Holstein-Rathlou, N H; Kanters, J K; Leyssac, P P

1988-01-01

Since hypertension is associated with changes in the handling of various cations (including sodium and lithium) across the cell membrane, the present study investigated the validity of the lithium clearance method in hypertension by comparing two measures of proximal reabsorption. Thus, fractional...... lithium excretion and transit time (TT)-occlusion time (OT; e-TT/T) were determined successively in the same spontaneously hypertensive rat (SHR, Okamoto strain). The rats were examined both before and after an acute saline load. The results show that the lithium clearance method can be used...... for the determination of proximal reabsorption in SHR. Utilizing the lithium clearance method, the changes in renal sodium handling underlying the exaggerated natriuresis were investigated in unanaesthetized catheterized rats. It was found that the exaggerated natriuresis was associated with an increased output from...

99mtechnetium-dimercapto-succinic acid renal scanning and excretory urography in diagnosis of renal scars in children

International Nuclear Information System (INIS)

McLorie, G.A.; Aliabadi, H.; Churchill, B.M.; Ash, J.M.; Gilday, D.L.

1989-01-01

We compared the ability of excretory urography (without tomography) and 99mtechnetium-dimercapto-succinic acid renal scanning to detect renal scars in 32 children with primary vesicoureteral reflux. These children did not have hydronephrosis, renal failure or urinary tract obstruction. In all cases both studies were conducted within a 10-month period. The findings from both modalities were in agreement for 51 of the 64 renal units evaluated (80%). Evaluation of the excretory urogram indicated 6 cases of diffuse and 2 of focal scarring that were not detected by evaluation of the renal scan. The sensitivity of excretory urography to detect renal scars was 84% and the specificity was 83%. The 99mtechnetium-dimercapto-succinic acid renal scan showed 5 cases of focal renal scarring not detected by excretory urography. The sensitivity of the renal scan to detect renal scars was 77% and the specificity was 75%. We conclude that neither study alone could effectively replace the other for the detection of renal scars, and recommend that both be included in the initial evaluation and followup of patients with renal scars

Evaluation of allograft perfusion by radionuclide first-pass study in renal failure following renal transplantation

International Nuclear Information System (INIS)

Baillet, G.; Ballarin, J.; Urdaneta, N.; Campos, H.; Vernejoul, P. de; Fermanian, J.; Kellershohn, C.; Kreis, H.

1986-01-01

To assess the diagnostic value of indices measured on a first-pass curve, we performed 72 radionuclide renal first-pass studies (RFP) in 21 patients during the early weeks following renal allograft transplantation. The diagnosis was based on standard clinical and biochemical data and on fine needle aspiration biopsy (FNAB) of the transplant. Aortic and renal first-pass curves were filtered using a true low-pass filter and five different indices of renal perfusion were computed, using formulae from the literature. Statistical analysis performed on the aortic and renal indices indicated excellent reproducibility of the isotopic study. Although renal indices presented a rather large scatter, they all discriminated well between normal and rejection. Three indices have a particularly good diagnostic value. In the discrimination between rejection and Acute Tubular Necrosis (ATN), only one index gave satisfying results. The indices, however, indicate that there are probably ATN with an alternation of renal perfusion and rejection episodes where perfusion is almost intact. We conclude that radionuclide first-pass study allows accurate and reproducible quantitation of renal allograft perfusion. The measured parameters are helpful to follow up the course of a post-transplantation renal failure episode and to gain more insight into renal ischemia following transplantation. (orig.)

CT features of renal infarction

International Nuclear Information System (INIS)

Suzer, Okan; Shirkhoda, Ali; Jafri, S. Zafar; Madrazo, Beatrice L.; Bis, Kostaki G.; Mastromatteo, James F.

2002-01-01

Purpose: To demonstrate the different patterns of renal infarction to avoid pitfalls. To present 'flip-flop enhancement' pattern in renal infarction. Materials and methods: Retrospective review of a total of 41 renal infarction in 37 patients were done. These patients underwent initial CT and the diagnosis of renal infarction was confirmed with either follow up CT or at surgery. Results: Twenty-three patients had wedge-shaped focal infarcts, nine patients had global and five patients had multifocal infarcts of the kidneys. Cortical rim sign was seen predominantly with global infarcts. In five patients, a 'flip-flop enhancement' pattern was observed. In two patients, planned renal biopsies due to tumefactive renal lesions were cancelled because of 'flip-flop enhancement' pattern on follow up CTs. Conclusion: Although most of our cases were straightforward for the diagnosis of renal infarction, cases with tumefactive lesions and global infarctions without the well-known cortical rim sign were particularly challenging. We describe a new sign, flip-flop enhancement pattern, which we believe solidified the diagnosis of renal infarction in five of our cases. The authors recommend further investigations for association of flip-flop enhancement and renal infarction

[Small renal mass].

Science.gov (United States)

Prokofiev, D; Kreutzer, N; Kress, A; Wissing, F; Pfeifer, H; Stolzenburg, J-U; Dietel, A; Schwalenberg, T; Do, M; Truß, M C

2012-10-01

The frequent application of ultrasound and radiological imaging for non-urological indications in recent years has resulted in an increase in the diagnosis of small renal masses. The treatment options for patients with a small renal mass include active surveillance, surgery (both open and minimally invasive) as well as ablative techniques. As there is a risk for metastatic spread even in small renal masses surgical extirpation remains the treatment of choice in most patients. Ablative procedures, such as cryoablation and radiofrequency ablation are appropriate for old and multi-morbid patients who require active treatment of a small renal mass. Active surveillance is an alternative for high-risk patients. Meticulous patient selection by the urologist and patient preference will determine the choice of treatment option in the future.

An experimental study on renal arterial and parenchymal change caused by selective renal infusion of epinephrine

International Nuclear Information System (INIS)

Jeon, Seok Chol; Yeon, Kyung Mo; Han, Man Chung

1981-01-01

Selective infusion of the epinephrine into the renal artery has been used in the field of the diagnostic and the therapeutic radiology for correct diagnosis and effective treatment, respectively. However, administration of overdose of epinephrine may cause serious complication, renal infarction. The study was undertaken to evaluate the sequential change of renal arterial constrictive effect of selective infusion of epinephrine into renal artery and to determine the critical doses of epinephrine producing irreversible renal infarct. A total of 25 rabbits are used, which are divided into 5 groups. Under the general anesthesia is made the selective infusion of various doses of epinephrine into the right renal artery of the rabbits. At the various time interval during and after the epinephrine infusion, renal angiography was done, and 24 hrs. later, gross and microscopic findings of the kidney were observed. The results are as follows; 1. Vasoconstriction of renal artery occurred within 2 mins. infusion, and maximum effect within 5 mins. 2. It seems that there is correlation between the amount of infused epinephrine and the time taken to recover from constriction of renal artery. 3. When epinephrine is infused into the renal artery in the rate of 1 ug/min., renal infarct is not noticed below the level of 10 mins., but correlation between the amount of infused epinephrine and the frequency of renal infarct occurs above 20 mins. infusion

Chemical renal denervation in the rat.

Science.gov (United States)

Consigny, Paul M; Davalian, Dariush; Donn, Rosy; Hu, Jie; Rieser, Matthew; Stolarik, Deanne

2014-02-01

The recent success of renal denervation in lowering blood pressure in drug-resistant hypertensive patients has stimulated interest in developing novel approaches to renal denervation including local drug/chemical delivery. The purpose of this study was to develop a rat model in which depletion of renal norepinephrine (NE) could be used to determine the efficacy of renal denervation after the delivery of a chemical to the periadventitial space of the renal artery. Renal denervation was performed on a single renal artery of 90 rats (n = 6 rats/group). The first study determined the time course of renal denervation after surgical stripping of a renal artery plus the topical application of phenol in alcohol. The second study determined the efficacy of periadventitial delivery of hypertonic saline, guanethidine, and salicylic acid. The final study determined the dose-response relationship for paclitaxel. In all studies, renal NE content was determined by liquid chromatography-mass spectrometry. Renal NE was depleted 3 and 7 days after surgical denervation. Renal NE was also depleted by periadventitial delivery of all agents tested (hypertonic saline, salicylic acid, guanethidine, and paclitaxel). A dose response was observed after the application of 150 μL of 10(-5) M through 10(-2) M paclitaxel. We developed a rat model in which depletion of renal NE was used to determine the efficacy of renal denervation after perivascular renal artery drug/chemical delivery. We validated this model by demonstrating the efficacy of the neurotoxic agents hypertonic saline, salicylic acid, and guanethidine and increasing doses of paclitaxel.

Infarction of renal transplant with extrarenal excretion of Tc-99m MAG3 demonstrated by renal scintigraphy

International Nuclear Information System (INIS)

Lim, Seok Tae; Kim, Min Woo; Sohn, Myung Hee

2003-01-01

A 38-year-old woman with end stage renal disease received a living related donor-renal transplant to the right iliac fossa. She developed anuria a week later. Tc-99m MAG 3 renal scintigraphy demonstrated no perfusion, uptake, or excretion of the radioactive tracer from the renal transplant. The expected area of the renal allograft appeared as a photopenic area with increased rim activity. The gallbladder and bowel activities were observed on delayed images at 24 hours. There was no blood flow within the renal artery on renal doppler examination. This case shows total absence of perfusion and function in the infarcted renal transplant with extrarenal excretion of Tc-99m MAG 3 caused by acute renal artery thrombosis

Intra-renal localised reno-renal collaterals in the dog after tying of the main renal artery

International Nuclear Information System (INIS)

Rosenbusch, G.; Vincent, J.; Douveren, W. van; Sktonicki, S.; Arts, T.H.M.; Katholieke Univ. Nijmegen; Katholieke Univ. Nijmegen

1984-01-01

In 7 kidneys of 6 dogs one of the main stem of the renal artery was ligated. The development of the renorenal collaterals could be followed in 5, as two dogs died after the operation. In all cases intrarenal collaterals could be demonstrated, even in the postoperative dead dogs. The vessels responsible for the collateral circulation are preformed interarterial anastomoses, belonging to the extraglomerular arterial system. From the results of these and former experimental studies it can be concluded, that the renal artery of the dog when entering the renal sinus cannot be regarded as an anatomic, but at most as a functional end artery. (orig.) [de

Intra-renal localised reno-renal collaterals in the dog after tying of the main renal artery

Energy Technology Data Exchange (ETDEWEB)

Rosenbusch, G.; Vincent, J.; Douveren, W. van; Sktonicki, S.; Arts, T.H.M.

1984-01-01

In 7 kidneys of 6 dogs one of the main stem of the renal artery was ligated. The development of the renorenal collaterals could be followed in 5, as two dogs died after the operation. In all cases intrarenal collaterals could be demonstrated, even in the postoperative dead dogs. The vessels responsible for the collateral circulation are preformed interarterial anastomoses, belonging to the extraglomerular arterial system. From the results of these and former experimental studies it can be concluded, that the renal artery of the dog when entering the renal sinus cannot be regarded as an anatomic, but at most as a functional end artery.

Protective effect of theophylline on renal functions in experimental pneumoperitoneum model.

Science.gov (United States)

Ozturk, Sefa Alperen; Ceylan, Cavit; Serel, Tekin Ahmet; Doluoglu, Omer Gokhan; Soyupek, Arap Sedat; Guzel, Ahmet; Özorak, Alper; Uz, Efkan; Savas, Hasan Basri; Baspinar, Sirin

2015-07-01

Our objective in this experimental study is to research the effect of the intra-abdominal pressure which rises following pneumoperitoneum and whether Theophylline has a possible protective activity on this situation. In our study, 24 Wistar Albino rats were used. Rats were divided into two groups. The first group was set for only pneumoperitoneum model. The second group was given 15 mg/kg of Theophylline intraperitoneally before setting pneumoperitoneum model. Then urea, creatinine, cystatin-C, tissue and serum total antioxidant capacity, total oxidant capacity and oxidative stress index in two groups were measured and compared with each other. Apoptosis and histopathological conditions in the renal tissues were examined. The differences between the groups were analyzed with the Mann-Whitney U test. Results were considered significant at p OSI values (p > 0.05). The mean value of urea were similar in pneumoperitoneum and pneumoperitoneum + theophylline groups (p = 0.12). The mean cystatin-C value was 2.2 ± 0.3 µg/mL in pneumoperitoneum, 1.74 ± 0.33 µg/mL in pneumoperitoneum + theophylline (p = 0.002). According to our study, lower cystatin-C levels in the group, where Theophylline was given, are suggestive of lower renal injury in this group. However, this opinion is interrogated as there is no difference in terms of tissue and serum TAS, TOS, OSI and urea values between the groups.

Influence of renal shielding on the incidence of late renal dysfunction associated with bone marrow transplantation

International Nuclear Information System (INIS)

Lawton, C.A.; Ash, R.C.; Murray, K.J.; Cohon, E.P.; Barher-Derus, S.W.; Moulder, J.E.

1991-01-01

This paper reports that late renal dysfunction following bone marrow transplantation has been described by a number of centers including the authors own. Total body irradiation seems to play a major causative role. In an effort to decrease the incidence of this renal toxicity, the authors have added customized partial transmission renal blocking to their total body irradiation regimen. The purpose of this study is to evaluate the effect of the renal blocking. The authors total body irradiation dose is 14 Gy. With the shielding used, the kidneys received approximately 12 Gy. Fifty-five adult patients have received total body irradiation with this renal shielding, compared with 73 adult patients who were treated without renal shielding. Eighteen percent (13 of 73) of patients who did not have renal shielding compared with only 7% (4 of 55) of patients with renal shielding have developed late renal dysfunction. Median follow-up in the non-blocked patients is 451 days after transplantation versus 282 days for the blocked patients

Accessory renal arteries: Prevalence in resistant hypertension and an important role in nonresponse to radiofrequency renal denervation

Energy Technology Data Exchange (ETDEWEB)

VonAchen, Paige [Minneapolis Heart Institute and Foundation at Abbott Northwestern Hospital, Minneapolis, MN (United States); Hamann, Jason [Boston Scientific Corporation, Maple Grove, MN (United States); Houghland, Thomas; Lesser, John R.; Wang, Yale; Caye, David; Rosenthal, Kristi; Garberich, Ross F. [Minneapolis Heart Institute and Foundation at Abbott Northwestern Hospital, Minneapolis, MN (United States); Daniels, Mary [Vital Images/Toshiba, Minnetonka, MN (United States); Schwartz, Robert S., E-mail: rss@rsschwartz.com [Minneapolis Heart Institute and Foundation at Abbott Northwestern Hospital, Minneapolis, MN (United States)

2016-10-15

Objective: The aim of this study was to understand the role of accessory renal arteries in resistant hypertension, and to establish their role in nonresponse to radiofrequency renal denervation (RDN) procedures. Background: Prior studies suggest a role for accessory renal arteries in hypertensive syndromes, and recent clinical trials of renal denervation report that these anomalies are highly prevalent in resistant hypertension. This study evaluated the relationships among resistant hypertension, accessory renal arteries, and the response to radiofrequency (RF) renal denervation. Methods: Computed Tomography Angiography (CTA) and magnetic resonance imaging (MRI) scans from 58 patients with resistant hypertension undergoing RF renal denervation (RDN) were evaluated. Results were compared with CT scans in 57 healthy, normotensive subjects undergoing screening as possible renal transplant donors. All scans were carefully studied for accessory renal arteries, and were correlated with long term blood pressure reduction. Results: Accessory renal arteries were markedly more prevalent in the hypertensive patients than normotensive renal donors (59% vs 32% respectively, p = 0.004). RDN had an overall nonresponse rate of 29% (response rate 71%). Patients without accessory vessels had a borderline higher response rate to RDN than those with at least one accessory vessel (83% vs 62% respectively, p = 0.076) and a higher RDN response than patients with untreated accessory arteries (83% vs 55%; p = 0.040). For accessory renal arteries and nonresponse, the sensitivity was 76%, specificity 49%, with positive and negative predictive values 38% and 83% respectively. Conclusions: Accessory renal arteries were markedly over-represented in resistant hypertensives compared with healthy controls. While not all patients with accessory arteries were nonresponders, nonresponse was related to both the presence and non-treatment of accessory arteries. Addressing accessory renal arteries in

Accessory renal arteries: Prevalence in resistant hypertension and an important role in nonresponse to radiofrequency renal denervation

International Nuclear Information System (INIS)

VonAchen, Paige; Hamann, Jason; Houghland, Thomas; Lesser, John R.; Wang, Yale; Caye, David; Rosenthal, Kristi; Garberich, Ross F.; Daniels, Mary; Schwartz, Robert S.

2016-01-01

Objective: The aim of this study was to understand the role of accessory renal arteries in resistant hypertension, and to establish their role in nonresponse to radiofrequency renal denervation (RDN) procedures. Background: Prior studies suggest a role for accessory renal arteries in hypertensive syndromes, and recent clinical trials of renal denervation report that these anomalies are highly prevalent in resistant hypertension. This study evaluated the relationships among resistant hypertension, accessory renal arteries, and the response to radiofrequency (RF) renal denervation. Methods: Computed Tomography Angiography (CTA) and magnetic resonance imaging (MRI) scans from 58 patients with resistant hypertension undergoing RF renal denervation (RDN) were evaluated. Results were compared with CT scans in 57 healthy, normotensive subjects undergoing screening as possible renal transplant donors. All scans were carefully studied for accessory renal arteries, and were correlated with long term blood pressure reduction. Results: Accessory renal arteries were markedly more prevalent in the hypertensive patients than normotensive renal donors (59% vs 32% respectively, p = 0.004). RDN had an overall nonresponse rate of 29% (response rate 71%). Patients without accessory vessels had a borderline higher response rate to RDN than those with at least one accessory vessel (83% vs 62% respectively, p = 0.076) and a higher RDN response than patients with untreated accessory arteries (83% vs 55%; p = 0.040). For accessory renal arteries and nonresponse, the sensitivity was 76%, specificity 49%, with positive and negative predictive values 38% and 83% respectively. Conclusions: Accessory renal arteries were markedly over-represented in resistant hypertensives compared with healthy controls. While not all patients with accessory arteries were nonresponders, nonresponse was related to both the presence and non-treatment of accessory arteries. Addressing accessory renal arteries in

Renal Sinus Fat Invasion and Tumoral Thrombosis of the Inferior Vena Cava-Renal Vein: Only Confined to Renal Cell Carcinoma

Directory of Open Access Journals (Sweden)

Turker Acar

2014-01-01

Full Text Available Epithelioid angiomyolipoma (E-AML, accounting for 8% of renal angiomyolipoma, is usually associated with tuberous sclerosis (TS and demonstrates aggressive behavior. E-AML is macroscopically seen as a large infiltrative necrotic tumor with occasional extension into renal vein and/or inferior vena cava. However, without history of TS, renal sinus and venous invasion E-AML would be a challenging diagnosis, which may lead radiologists to misinterpret it as a renal cell carcinoma (RCC. In this case presentation, we aimed to report cross-sectional imaging findings of two cases diagnosed as E-AML and pathological correlation of these aforementioned masses mimicking RCC.

Renal artery pseudoaneurysm

Directory of Open Access Journals (Sweden)

Luiz Inácio Roman

Full Text Available Abstract The renal artery pseudoaneurysm embody a rare vascular complication coming of percutaneous procedures, renal biopsy, nephrectomy, penetrating traumas and more rarely blunt traumas. The clinical can be vary according the patient, the haematuria is the symptom more commom. Is necessary a high level of clinical suspicion for your diagnosis, this can be elucidated by through complementary exams as the eco-color Doppler and the computed tomography scan (CT. This report is a case of a patient submitted a right percutaneous renal biopsy and that, after the procedure started with macroscopic haematuria, urinary tenesmus and hypogastric pain. The diagnosis of pseudoaneurysm was given after one week of evolution when the patient was hospitalized because gross haematuria, tachycardia, hypotension and hypochondrium pain. In the angiotomography revealed a focal dilation of the accessory right renal inferior polar artery, dilation of renal pelvis and all the ureteral course with presence hyperdenso material (clots inside the middle third of the ureter. The treatment for the majority of this cases are conservative, through arterial embolization, indicated for thouse of smaller dimensions in patients who are hemodynamically stable. However, it was decided by clinical treatment with aminocaproic acid 1 g, according to previous studies for therapy of haematuria. The patient received discharge without evidence of macroscopic haematuria and with normal renal ultrasound, following ambulatory care.

Role of H2O2 on the kinetics of low-affinity high-capacity Na+-dependent alanine transport in SHR proximal tubular epithelial cells

International Nuclear Information System (INIS)

Pinto, Vanda; Pinho, Maria Joao; Jose, Pedro A.; Soares-da-Silva, Patricio

2010-01-01

Research highlights: → H 2 O 2 in excess is required for the presence of a low-affinity high-capacity component for the Na + -dependent [ 14 C]-L-alanine uptake in SHR PTE cells only. → It is suggested that Na + binding in renal ASCT2 may be regulated by ROS in SHR PTE cells. -- Abstract: The presence of high and low sodium affinity states for the Na + -dependent [ 14 C]-L-alanine uptake in immortalized renal proximal tubular epithelial (PTE) cells was previously reported (Am. J. Physiol. 293 (2007) R538-R547). This study evaluated the role of H 2 O 2 on the Na + -dependent [ 14 C]-L-alanine uptake of ASCT2 in immortalized renal PTE cells from Wistar Kyoto rat (WKY) and spontaneously hypertensive rat (SHR). Na + dependence of [ 14 C]-L-alanine uptake was investigated replacing NaCl with an equimolar concentration of choline chloride in vehicle- and apocynin-treated cells. Na + removal from the uptake solution abolished transport activity in both WKY and SHR PTE cells. Decreases in H 2 O 2 levels in the extracellular medium significantly reduced Na + -K m and V max values of the low-affinity high-capacity component in SHR PTE cells, with no effect on the high-affinity low-capacity state of the Na + -dependent [ 14 C]-L-alanine uptake. After removal of apocynin from the culture medium, H 2 O 2 levels returned to basal values within 1 to 3 h in both WKY and SHR PTE cells and these were found stable for the next 24 h. Under these experimental conditions, the Na + -K m and V max of the high-affinity low-capacity state were unaffected and the low-affinity high-capacity component remained significantly decreased 1 day but not 4 days after apocynin removal. In conclusion, H 2 O 2 in excess is required for the presence of a low-affinity high-capacity component for the Na + -dependent [ 14 C]-L-alanine uptake in SHR PTE cells only. It is suggested that Na + binding in renal ASCT2 may be regulated by ROS in SHR PTE cells.

No effect of dietary fish oil on renal hemodynamics, tubular function, and renal functional reserve in long-term renal transplant recipients

DEFF Research Database (Denmark)

Hansen, J M; Løkkegaard, H; Høy, Carl-Erik

1995-01-01

Dietary supplementation with fish oil rich in n-3 polyunsaturated fatty acids has been suggested to protect the kidney against cyclosporin A (CsA) toxicity. This study investigated the effects of a 10-wk dietary supplementation with fish oil on renal function and renal functional reserve in healt...... transplant recipients treated with a low maintenance dose of CsA had a well-preserved renal functional reserve, and dietary supplementation with fish oil in these patients did not improve renal function.......Dietary supplementation with fish oil rich in n-3 polyunsaturated fatty acids has been suggested to protect the kidney against cyclosporin A (CsA) toxicity. This study investigated the effects of a 10-wk dietary supplementation with fish oil on renal function and renal functional reserve in healthy...... volunteers (N = 9) and two groups of stable long-term kidney-transplanted patients treated with maintenance low-dose CsA (3.0 +/- 0.6 mg/kg; N = 9) or without CsA (N = 9). After an overnight fast, the subjects were water loaded, and clearance studies were performed, postponing morning medication. GFR...

Ultrasonography in chronic renal failure

International Nuclear Information System (INIS)

Buturovic-Ponikvar, Jadranka; Visnar-Perovic, Alenka

2003-01-01

Many chronic renal diseases lead to the final common state of decrease in renal size, parenchymal atrophy, sclerosis and fibrosis. The ultrasound image show a smaller kidney, thinning of the parenchyma and its hyperechogenicity (reflecting sclerosis and fibrosis). The frequency of renal cysts increases with the progression of the disease. Ultrasound generally does not allow for the exact diagnosis of an underlying chronic disease (renal biopsy is usually required), but it can help to determine an irreversible disease, assess prognosis and avoid unnecessary diagnostic or therapeutic procedures. The main exception in which the ultrasound image does not show a smaller kidney with parenchymal atrophy is diabetic nephropathy, the leading cause of chronic and end-stage renal failure in developed countries in recent years. In this case, both renal size and parenchymal thickness are preserved until end-stage renal failure. Doppler study of intrarenal vessels can provide additional information about microvascular and parenchymal lesions, which is helpful in deciding for or against therapeutic intervention and timely planning for optimal renal replacement therapy option

Chemical Renal Denervation in the Rat

Energy Technology Data Exchange (ETDEWEB)

Consigny, Paul M., E-mail: paul.consigny@av.abbott.com; Davalian, Dariush, E-mail: dariush.davalian@av.abbott.com [Abbott Vascular, Innovation Incubator (United States); Donn, Rosy, E-mail: rosy.donn@av.abbott.com; Hu, Jie, E-mail: jie.hu@av.abbott.com [Abbott Vascular, Bioanalytical and Material Characterization (United States); Rieser, Matthew, E-mail: matthew.j.rieser@abbvie.com; Stolarik, DeAnne, E-mail: deanne.f.stolarik@abbvie.com [Abbvie, Analytical Pharmacology (United States)

2013-12-03

Introduction: The recent success of renal denervation in lowering blood pressure in drug-resistant hypertensive patients has stimulated interest in developing novel approaches to renal denervation including local drug/chemical delivery. The purpose of this study was to develop a rat model in which depletion of renal norepinephrine (NE) could be used to determine the efficacy of renal denervation after the delivery of a chemical to the periadventitial space of the renal artery. Methods: Renal denervation was performed on a single renal artery of 90 rats (n = 6 rats/group). The first study determined the time course of renal denervation after surgical stripping of a renal artery plus the topical application of phenol in alcohol. The second study determined the efficacy of periadventitial delivery of hypertonic saline, guanethidine, and salicylic acid. The final study determined the dose–response relationship for paclitaxel. In all studies, renal NE content was determined by liquid chromatography–mass spectrometry. Results: Renal NE was depleted 3 and 7 days after surgical denervation. Renal NE was also depleted by periadventitial delivery of all agents tested (hypertonic saline, salicylic acid, guanethidine, and paclitaxel). A dose response was observed after the application of 150 μL of 10{sup −5} M through 10{sup −2} M paclitaxel. Conclusion: We developed a rat model in which depletion of renal NE was used to determine the efficacy of renal denervation after perivascular renal artery drug/chemical delivery. We validated this model by demonstrating the efficacy of the neurotoxic agents hypertonic saline, salicylic acid, and guanethidine and increasing doses of paclitaxel.

Chemical Renal Denervation in the Rat

International Nuclear Information System (INIS)

Consigny, Paul M.; Davalian, Dariush; Donn, Rosy; Hu, Jie; Rieser, Matthew; Stolarik, DeAnne

2014-01-01

Introduction: The recent success of renal denervation in lowering blood pressure in drug-resistant hypertensive patients has stimulated interest in developing novel approaches to renal denervation including local drug/chemical delivery. The purpose of this study was to develop a rat model in which depletion of renal norepinephrine (NE) could be used to determine the efficacy of renal denervation after the delivery of a chemical to the periadventitial space of the renal artery. Methods: Renal denervation was performed on a single renal artery of 90 rats (n = 6 rats/group). The first study determined the time course of renal denervation after surgical stripping of a renal artery plus the topical application of phenol in alcohol. The second study determined the efficacy of periadventitial delivery of hypertonic saline, guanethidine, and salicylic acid. The final study determined the dose–response relationship for paclitaxel. In all studies, renal NE content was determined by liquid chromatography–mass spectrometry. Results: Renal NE was depleted 3 and 7 days after surgical denervation. Renal NE was also depleted by periadventitial delivery of all agents tested (hypertonic saline, salicylic acid, guanethidine, and paclitaxel). A dose response was observed after the application of 150 μL of 10 −5  M through 10 −2  M paclitaxel. Conclusion: We developed a rat model in which depletion of renal NE was used to determine the efficacy of renal denervation after perivascular renal artery drug/chemical delivery. We validated this model by demonstrating the efficacy of the neurotoxic agents hypertonic saline, salicylic acid, and guanethidine and increasing doses of paclitaxel

Renal cancer.

NARCIS (Netherlands)

Corgna, E.; Betti, M.; Gatta, G.; Roila, F.; Mulder, P.H.M. de

2007-01-01

In Europe, renal cancer (that is neoplasia of the kidney, renal pelvis or ureter (ICD-9 189 and ICD-10 C64-C66)) ranks as the seventh most common malignancy in men amongst whom there are 29,600 new cases each year (3.5% of all cancers). Tobacco, obesity and a diet poor in vegetables are all

Renal cancer

NARCIS (Netherlands)

Corgna, Enrichetta; Betti, Maura; Gatta, Gemma; Roila, Fausto; De Mulder, Pieter H. M.

2007-01-01

In Europe, renal cancer (that is neoplasia of the kidney, renal pelvis or ureter (ICD-9 189 and ICD-10 C64-C66)) ranks as the seventh most common malignancy in men amongst whom there are 29,600 new cases each year (3.5% of all cancers). Tobacco, obesity and a diet poor in vegetables are all

Effect of magnesium deficiency on renal magnesium and calcium transport in the rat.

OpenAIRE

Carney, S L; Wong, N L; Quamme, G A; Dirks, J H

1980-01-01

Recollection of micropuncture experiments were performed on acutely thyroparathyroidectomized rats rendered magnesium deficient by dietary deprivation. Urinary magnesium excretion fell from a control of 15 to 3% of the filtered load after magnesium restriction. The loop of Henle, presumably the thick ascending limb, was the major modulator for renal magnesium homeostasis. The transport capacity for magnesium, however, was less in deficient rats than control animals. Absolute magnesium reabsor...

Renal osteodystrophy in non-dialysed patients with chronic renal failure

International Nuclear Information System (INIS)

Andresen, J.; Nielsen, H.E.

1980-01-01

Radiologic bone lesions in 92 non-dialysed patients with chronic renal failure are described. The bone disease increased with the severity of renal failure. In a prospective series of 20 patients progression of osteodystrophy and decrease in metacarpal bone mass were demonstrated. (Auth.)

Stages of Renal Cell Cancer

Science.gov (United States)

... Tumors Treatment Genetics of Kidney Cancer Research Renal Cell Cancer Treatment (PDQ®)–Patient Version General Information About Renal Cell Cancer Go to Health Professional Version Key Points Renal ...

Ultrasonography assessment of renal size and its correlation with body mass index in adults without known renal disease

International Nuclear Information System (INIS)

Raza, M.; Hameed, A.; Khan, M.I.

2012-01-01

Many conditions affect renal size. To evaluate abnormalities in renal size, knowledge of standardised values for normal renal dimensions is essential as it shows variability in the values of normal renal size depending on body size, age and ethnicity. Ultrasound, being an easily available, non-invasive, safe and less expensive modality, is widely used for evaluation of renal dimensions and repeated follow-ups. The objectives of this study were to determine renal size by ultrasound in adults without any known renal disease, and to determine the relationship of renal size with body mass index. Methods: Study was conducted in the Department of Diagnostic Radiology, Shifa International Hospital and PIMS Islamabad. Renal size was assessed by ultrasound in 4,035 adult subjects with normal serum creatinine and without any known renal disease, between November 2002 and December 2010. Renal length, width, thickness and volume were obtained and mean renal length and volume were correlated with body mass index and other factors like age, side, gender, weight and height of the subjects. Results: Mean renal length on right side was 101.6+-8.9 mm, renal width 42.7+-7.1 mm, and parenchymal thickness 14.4+-2.9 mm. On left side, mean renal length was 102.7+-9.2 mm, width 47.6+-7.0 mm, and parenchymal thickness 15.1+-3.1 mm. Mean renal volume on right was 99.8+-37.2 cm/sup 3/ and on left was 124.4+-41.3 cm/sup 3/. Left renal size was significantly larger than right in both genders. Relationship of mean renal length was significant when correlated with age, side, gender, height and weight, and body mass index. Renal volumes also showed a similar relationship with side, gender, height and weight, and body mass index; but with age such a relationship was seen only for left kidney. Conclusion: Pakistani population has mean renal size smaller than reference values available in international literature. Renal length and volume have a direct relationship with body mass index. Mean renal

Renal denervation prevents long-term sequelae of ischemic renal injury

Science.gov (United States)

Kim, Jinu; Padanilam, Babu J.

2014-01-01

Signals that drive interstitial fibrogenesis after renal ischemia reperfusion injury remain undefined. Sympathetic activation is manifest even in the early clinical stages of chronic kidney disease and is directly related to disease severity. A role for renal nerves in renal interstitial fibrogenesis in the setting of ischemia reperfusion injury has not been studied. In male 129S1/SvImJ mice, ischemia reperfusion injury induced tubulointerstitial fibrosis as indicated by collagen deposition and profibrotic protein expression 4 to 16 days after the injury.. Leukocyte influx, proinflammatory protein expression, oxidative stress, apoptosis, and cell cycle arrest at G2/M phase were enhanced after ischemia reperfusion injury. Renal denervation at the time of injury or up to 1 day post-injury improved histology, decreased proinflammatory/profibrotic responses and apoptosis, and prevented G2/M cell cycle arrest in the kidney. Treatment with afferent nerve-derived calcitonin gene-related peptide (CGRP) or efferent nerve-derived norepinephrine in denervated and ischemia reperfusion injury-induced kidneys mimicked innervation, restored inflammation and fibrosis, induced G2/M arrest, and enhanced TGF-β1 activation. Blocking norepinephrine or CGRP function using respective receptor blockers prevented these effects. Consistent with the in vivo study, treatment with either norepinephrine or CGRP induced G2/M cell cycle arrest in HK-2 proximal tubule cells, whereas antagonists against their respective receptors prevented G2/M arrest. Thus, renal nerve stimulation is a primary mechanism and renal nerve-derived factors drive epithelial cell cycle arrest and the inflammatory cascade causing interstitial fibrogenesis after ischemia reperfusion injury. PMID:25207878

Biopsia Renal en receptores de Trasplante Renal: cuidados de enfermería y complicaciones

Directory of Open Access Journals (Sweden)

Esther Sanz Izquierdo

Full Text Available Introducción: La biopsia renal percutánea es una herramienta fundamental para el manejo del paciente trasplantado renal. La prueba es primordial para detectar y/o prevenir cualquier disfunción en el injerto, siendo un procedimiento tanto diagnóstico como preconizador. Objetivo: Describir los cuidados de enfermería e identificar las complicaciones derivadas de la biopsia renal en los receptores de Trasplante Renal. Material y métodos: Estudio cuantitativo, descriptivo y transversal realizado en la Unidad de Trasplante Renal, Servicio de Nefrología, del 2008 al 2014. La población objeto de estudio son los receptores de Trasplante Renal (TR. La muestra está compuesta por 368 biopsias renales de seguimiento que ingresan para someterse a una biopsia renal. Los criterios de inclusión son ser mayores de 18 años, trasplantados y que han firmado el consentimiento informado. Se recogen datos sociodemográficos, clínico-asistenciales y complicaciones post-biopsia renal. Resultados: Desde 1980 hasta el 2014 se han llevado a cabo 1868 TR, de 2008 a 2014 se estudiaron 368 biopsias de seguimiento. Se monitoriza la Tensión Arterial y la coagulación pre biopsia. Tras el procedimiento, se controla la presencia de sangrado por micción y constantes vitales. Inicialmente el reposo absoluto era de 24 h, a partir de 2014 se reduce a 6 horas, recomendando reposo relativo al alta, las complicaciones fueron mínimas. Conclusiones: Los resultados indican que la biopsia renal es un procedimiento eficaz, con escasas complicaciones. Destacar el papel de enfermería en la detección precoz de complicaciones.

Renal damage detected by DMSA, despite normal renal ultrasound, in children with febrile UTI.

Science.gov (United States)

Bush, N C; Keays, M; Adams, C; Mizener, K; Pritzker, K; Smith, W; Traylor, J; Villanueva, C; Snodgrass, W T

2015-06-01

2011 American Academy of Pediatrics guidelines recommended renal-bladder ultrasound (RBUS) as the only evaluation after febrile urinary tract infection (FUTI) in infants aged 2-24 months. We determined the sensitivity, specificity, and false negative rate of RBUS to identify DMSA-detected renal damage in this age group as well as in older children. Consecutive patients referred to pediatric urology with a history of FUTI underwent DMSA ≥ 3 months after FUTI. Abnormal RBUS was defined as: Society of Fetal Urology hydronephrosis grades I-IV; hydroureter ≥ 7 mm; renal scar defined as focal parenchymal thinning; and/or size discrepancy ≥ 1 cm between kidneys. Abnormal DMSA was presence of any focal uptake defects and/or split renal function 24 months. RBUS had poor sensitivity (34%) and low positive predictive value (47%) to identify patients with renal damage. 99/149 (66%) children with renal damage on DMSA had normal RBUS. After FUTI, 66% of children with reduced renal function and/or renal cortical defects found by DMSA scintigraphy had a normal RBUS. Since abnormal DMSA may correlate with increased risk for VUR, recurrent FUTI and renal damage, our data suggest RBUS alone will fail to detect a significant proportion of patients at risk. The data suggest that imaging after FUTI should include acute RBUS and delayed DMSA, reserving VCUG for patients with abnormal DMSA and/or recurrent FUTI. Copyright © 2015 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

CT diagnosis of simple renal cysts

International Nuclear Information System (INIS)

Nanakawa, Seito; Yasunaga, Tadamasa; Tsuchigame, Tadatoshi; Kawano, Shoji; Takahashi, Mutsumasa; Fukui, Koutaro.

1987-01-01

CT is indispensable in the evaluation of renal masses, providing noninvasive and clear transverse images. With wider clinical application of CT, renal cysts have been found more frequently. CT examinations on 500 patients, who underwent CT for the diagnosis of renal diseases except for renal cysts, have been reviewed and analysed. The incidence of renal cysts was 9.6 % without prediction for sexes, but the incidence and sizes of the cysts increased with the advancing age. The upper portion of the kidneys was more frequently involved, but there was no relationship between number, sex and age of the patients. Since renal cysts produce mass effect in the kidneys, understanding of the nature and incidence of the renal cysts is important in diagnosing renal mass lesions. (author)

Renal function after prolonged hypotensive anesthesia and surgery in dogs with reduced renal mass.

Science.gov (United States)

Stone, E A; Rawlings, C A; Finco, D R; Crowell, W A

1981-10-01

The effect of prolonged hypotensive anesthesia and surgery on renal function was studied in 8 dogs with decreased renal mass. Renal mass was reduced by unilateral nephrectomy and ligation of 4 of the 6 terminal renal artery branches of the opposite kidney. One week after reduction in renal mass, the dogs were azotemic with a serum urea nitrogen (SUN) value of 65.8 +/- 11.5 mg/dl. Glomerular filtration rate, as estimated by 14C-inulin clearance, was 0.66 +/- 0.19 ml/kg of body weight/hour. A mean arterial pressure of less than 75 mm of Hg was maintained for 4 hours in dogs given 2.3 +/- 0.7% halothane. An exploratory laparotomy lasting 1 hour was performed. The day after the hypotensive episode, 3 dogs began vomiting, became dehydrated, and had SUN values greater than 100 mg/dl. The SUN values returned to base-line values after the dogs were rehydrated. Eight days after the hypotensive episode, 14C-inulin clearance decreased 15.2 +/- 8.2% (P less than 0.005) compared with base-line clearance values. Light microscopic and electron microscopic observations of the kidneys did not demonstrate acute renal failure. Prolonged hypotensive anesthesia can cause a decrease in renal function, and may cause prerenal uremia and/or acute renal failure.

Renal artery anatomy affects the blood pressure response to renal denervation in patients with resistant hypertension.

Science.gov (United States)

Hering, Dagmara; Marusic, Petra; Walton, Antony S; Duval, Jacqueline; Lee, Rebecca; Sata, Yusuke; Krum, Henry; Lambert, Elisabeth; Peter, Karlheinz; Head, Geoff; Lambert, Gavin; Esler, Murray D; Schlaich, Markus P

2016-01-01

Renal denervation (RDN) has been shown to reduce blood pressure (BP), muscle sympathetic nerve activity (MSNA) and target organ damage in patients with resistant hypertension (RH) and bilateral single renal arteries. The safety and efficacy of RDN in patients with multiple renal arteries remains unclear. We measured office and 24-hour BP at baseline, 3 and 6 months following RDN in 91 patients with RH, including 65 patients with single renal arteries bilaterally (group 1), 16 patients with dual renal arteries on either one or both sides (group 2) and 10 patients with other anatomical constellations or structural abnormalities (group 3). Thirty nine out of 91 patients completed MSNA at baseline and follow-up. RDN significantly reduced office and daytime SBP in group 1 at both 3 and 6 months follow-up (Pkidney function in any group. While RDN can be performed safely irrespective of the underlying renal anatomy, the presence of single renal arteries with or without structural abnormalities is associated with a more pronounced BP and MSNA lowering effect than the presence of dual renal arteries in patients with RH. However, when patients with dual renal arteries received renal nerve ablation in all arteries there was trend towards a greater BP reduction. Insufficient renal sympathetic nerve ablation may account for these differences. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Respiratory Syncytial Virus Aggravates Renal Injury through Cytokines and Direct Renal Injury

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Songhui Zhai

2016-09-01

Full Text Available The purpose of this study was to investigate the relationship between renal injury and reinfection that is caused by respiratory syncytial virus (RSV and to analyze the mechanism of renal injury. Rats were repeatedly infected with RSV on days 4, 8, 14, and 28, then sacrificed and examined on day 56 after the primary infection. Renal injury was examined by transmission electron microscopy and histopathology. The F protein of RSV was detected in the renal tissue by indirect immunofluorescence. Proteinuria and urinary glycosaminoglycans (GAGs, serum levels of albumin, urea nitrogen, and creatinine, secretion of cytokines, T lymphocyte population and subsets, and dendritic cell (DC activation state were examined. The results showed that renal injury was more serious in the reinfection group than in the primary infection group. At a higher infection dose, 6×106 PFU, the renal injury was more severe, accompanied by higher levels of proteinuria and urinary GAGs excretion, and lower levels of serum albumin. Podocyte foot effacement was more extensive, and hyperplasia of mesangial cells and proliferation of mesangial matrix were observed. The maturation state of DCs was specific, compared with the primary infection. There was also a decrease in the ratio of CD4+ to CD8+T lymphocytes, due to an increase in the percentage of CD8+T lymphocytes and a decrease in the percentage of CD4+T lymphocytes, and a dramatic increase in the levels of IL-6 and IL-17. In terms of the different reinfection times, the day 14 reinfection group yielded the most serious renal injury and the most significant change in immune function. RSV F protein was still expressed in the glomeruli 56 days after RSV infection. Altogether, these results reveal that RSV infection could aggravate renal injury, which might be due to direct renal injury caused by RSV and the inflammatory lesions caused by the anti-virus response induced by RSV.

Sodium-glucose co-transporter 2 (SGLT2 inhibitors: a growing class of anti-diabetic agents

Directory of Open Access Journals (Sweden)

Eva M Vivian

2014-12-01

Full Text Available Although several treatment options are available to reduce hyperglycemia, only about half of individuals with diagnosed diabetes mellitus (DM achieve recommended glycemic targets. New agents that reduce blood glucose concentrations by novel mechanisms and have acceptable safety profiles are needed to improve glycemic control and reduce the complications associated with type 2 diabetes mellitus (T2DM. The renal sodium-glucose co-transporter 2 (SGLT2 is responsible for reabsorption of most of the glucose filtered by the kidney. Inhibitors of SGLT2 lower blood glucose independent of the secretion and action of insulin by inhibiting renal reabsorption of glucose, thereby promoting the increased urinary excretion of excess glucose. Canagliflozin, dapagliflozin, and empagliflozin are SGLT2 inhibitors approved as treatments for T2DM in the United States, Europe, and other countries. Canagliflozin, dapagliflozin, and empagliflozin increase renal excretion of glucose and improve glycemic parameters in patients with T2DM when used as monotherapy or in combination with other antihyperglycemic agents. Treatment with SGLT2 inhibitors is associated with weight reduction, lowered blood pressure, and a low intrinsic propensity to cause hypoglycemia. Overall, canagliflozin, dapagliflozin, and empagliflozin are well tolerated. Cases of genital infections and, in some studies, urinary tract infections have been more frequent in canagliflozin-, dapagliflozin-, and empagliflozin-treated patients compared with those receiving placebo. Evidence from clinical trials suggests that SGLT2 inhibitors are a promising new treatment option for T2DM.

Effects of adenosine infusion into renal interstitium on renal hemodynamics

International Nuclear Information System (INIS)

Pawlowska, D.; Granger, J.P.; Knox, F.G.

1987-01-01

This study was designed to investigate the hemodynamic effects of exogenous adenosine in the interstitium of the rat kidney. Adenosine or its analogues were infused into the renal interstitium by means of chronically implanted capsules. In fusion of adenosine decreased glomerular filtration rate (GFR) from 0.81 +/- 0.06 to 0.37 +/- 0.06 ml/min while having no effect on renal blood flow (RBF). The metabolically stable analogue, 2-chloradenosine (2-ClAdo), decreased GFR from 0.73 +/- 0.07 to 021 +/- 0.06 ml/min. Interstitial infusion of theophylline, an adenosine receptor antagonist, completely abolished the effects of adenosine and 2-ClAdo on GFR. The distribution of adenosine, when infused into the renal interstitium, was determined using radiolabeled 5'-(N-ethyl)-carboxamidoadenosine (NECA), a metabolically stable adenosine agonist. After continuous infusion, [ 3 H]NECA was distributed throughout the kidney. The effects of NECA to reduce GFR were similar to those of adenosine and 2-ClAdo. They conclude that increased levels of adenosine in the renal interstitium markedly decrease GFR without affecting RBF in steady-state conditions. The marked effects of adenosine agonists during their infusion into the renal interstitium and the complete blockade of these effects by theophylline suggest an extracellular action of adenosine

Índice de resistividade renal como preditor da revascularização renal para hipertensão renovascular Índice de resistividad renal como predictor de la revascularización renal para hipertensión renovascular Renal resistance index predicting outcome of renal revascularization for renovascular hypertension

Directory of Open Access Journals (Sweden)

Simone N. Santos

2010-04-01

Full Text Available FUNDAMENTO: A estenose arterial renal (EAR é uma causa potencialmente reversível de hipertensão arterial sistêmica (HAS e nefropatia isquêmica. Apesar da revascularização bem sucedida, nem todos os pacientes (pt apresentam melhora clínica e alguns podem piorar. OBJETIVO: O presente estudo se destina a avaliar o valor do índice de resistividade renal (IR como preditor dos efeitos da revascularização renal. MÉTODOS: Entre janeiro de 1998 e fevereiro de 2001, 2.933 pacientes foram submetidos ao duplex ultrassom renal. 106 desses pacientes apresentaram EAR significativa e foram submetidos a angiografia e revascularização renal. A pressão arterial (PA foi medida antes e depois da intervenção, em intervalos de até 2 anos e as medicações prescritas foram registradas. Antes da revascularização, o IR foi medido em 3 locais do rim, sendo obtida uma média dessas medições. RESULTADOS: Dos 106 pacientes, 81 tiveram IR80. A EAR foi corrigida somente por angioplastia (PTA em 25 pts, PTA + stent em 56 pts e cirurgicamente em 25 pts. Dos pacientes que se beneficiaram da revascularização renal; 57 dos 81 pacientes com IR 80. Usando um modelo de regressão logística múltipla, o IR esteve significativamente associado à evolução da PA (p = 0,001, ajustado de acordo com os efeitos da idade, sexo, PAS, PAD, duração da hipertensão, o tipo de revascularização, número de fármacos em uso, nível de creatinina, presença de diabete melito, hipercolesterolemia, volume sistólico, doença arterial periférica e coronariana e tamanho renal (OR 99,6-95%CI para OR 6,1-1.621,2. CONCLUSÃO: A resistividade intrarrenal arterial, medida por duplex ultrassom, desempenha um papel importante na predição dos efeitos pós revascularização renal para EAR.FUNDAMENTO: La estenosis arterial renal (EAR es una causa potencialmente reversible de hipertensión arterial sistémica (HAS y nefropatía isquémica. Pese a que la revascularización sea

Role of RENAL nephrometry scoring system in planning surgical intervention in patients with localized renal mas

OpenAIRE

Mohamed Samir Shaaban; Tamer Mohammed Abou Youssif; Ahmed Mostafa; Hossam Eldin Hegazy; Mohammed Adel Atta

2015-01-01

Purpose: The study was designed to validate the value of preoperative planning using RENAL nephrometry scoring system in patients having organ confined renal tumors and undergoing surgical intervention and to assess its correlation with the surgical technique. Patient and methods: Forty patients with organ-confined renal masses underwent RENAL nephrometry scoring which was correlated with the surgical technique either radical or nephron-sparing surgery. Result: RENAL nephrometry scoring...

Ultrasound scan in the diagnosis of neonatal renal candidiasis; Ecografia en el diagnostico de la candidiasis renal neonatal

Energy Technology Data Exchange (ETDEWEB)

Muro, D.; Sanguesa, C.; Torres, D.; Berbel, O.; Andres, V. [Hospital Infantil La Fe. Valencia (Spain)

2003-07-01

To describe the most pertinent echographic findings regarding systemic and renal candidiasis in high-risk neonates. Echographic findings and clinical histories of 40 neonates in the neonatal intensive care unit were retrospectively analyzed. Thirty-eight presented systemic candidiasis with renal participation, while two showed only renal candidiasis. Ultrasound scans were performed using 7.5 MHz probes. Alterations in renal echo structure, presence of echogenic material without acoustic shadowing in the excretory system (mycetoma), presence of lithiasis, pyonephrosis and associated renal malformations were all evaluated. Ten patients presented renal alterations in ultrasound scan. Six children had originally shown increased eye-catching in the renal parenchyma which was resolved after medical treatment. Four children presented renal mycetoma, and in two there were renal malformations. Both of these exhibited a profile for pyonephrosis. One patient with renal mycetoma without urological abnormalities developed a lithiasis. Surgical intervention was unnecessary in all cases. The most common echographic findings in immature high-risk low-weight patients with systemic and renal candidiasis were alterations in the eye-catching of renal parenchyma and the presence of mycetoma. (Author) 22 refs.

Three-dimensional renal CT angiography for guiding segmental renal artery clamping during laparoscopic partial nephrectomy

International Nuclear Information System (INIS)

Xu, Yi; Shao, Pengfei; Zhu, Xiaomei; Lv, Qiang; Liu, Wangyan; Xu, Hai; Zhu, Yinsu; Yang, Guangyu; Tang, Lijun; Yin, Changjun

2013-01-01

Aim: To evaluate the effectiveness of three-dimensional (3D) renal computed tomography angiography (CTA) in guiding segmental renal artery clamping during laparoscopic partial nephrectomy (LPN). Materials and methods: Forty-three patients with renal tumours undergoing renal CTA before LPN were retrospectively enrolled in this study. 3D arteriogram reconstructed images were created to identify the renal tumour-supplying arteries. The number and location of these targeted vessels were annotated on 3D images preoperatively and compared with the clamped vessels during LPN. The consistency between target vessels annotated at CTA and clamped arteries at LPN was compared both using a patient-based analysis and vessel-based analysis. The χ 2 test was applied to analyse the influence of tumour size, location, and growth pattern on the number of clamped segmental renal branches. Results: On patient-based analysis, the number of targeted vessels was consistent with the clamped vessels during LPN in 33 of 43 patients. On vessel-based analysis, 56 of 65 target vessels annotated at CTA were clamped during LPN. More segmental renal branches (p = 0.04) were clamped in patients with tumours of larger size. Tumour location and growth pattern had no association with the number of clamped segmental branches during LPN. Conclusion: High-quality CTA images and 3D reconstruction images can detect detailed information of tumour-supplying arteries to renal tumours. 3D renal CTA is an effective way to guide segmental renal artery clamping during LPN

Impaired renal allograft function is associated with increased arterial stiffness in renal transplant recipients

DEFF Research Database (Denmark)

Kneifel, M; Scholze, A; Burkert, A

2006-01-01

It is important whether impairment of renal allograft function may deteriorate arterial stiffness in renal transplant recipients. In a cross-sectional study, arterial vascular characteristics were non-invasively determined in 48 patients with renal allograft using applanation tonometry and digital...

Renal involvement in behcet's disease

International Nuclear Information System (INIS)

Ardalan, Mohammad Reza; Noshad, Hamid; Sadreddini, Shahram; Ebrahimi, Aliasghar; Molaeefard, Mahsheed; Somi, Mohammad Hossein; Shoja, Mohammadali Mohajel

2009-01-01

There are conflicting reports about the renal involvement in Behcet's disease (BD). In this study we aimed to study the frequency and type of renal involvement in a group of patients with BD in Azerbaijan province that is one of the prevalent areas of BD in Iran. All cases of BD were prospectively followed between June 2004 and January 2007, and evaluated for renal dys-function (serum creatinine > 1.7 mg/dL), glomerular hematuria and proteinuria. Those patients with proteinuria > 500 mg/day and serum creatinine level > 2 mg/dL, underwent renal biopsy. From a total number of 100 patients, six patients (6%) had obvious renal involvements. Four patients had glomerular hematuria and proteinuria. Renal biopsy in two of them revealed measangial proliferative glumerulonephritis with IgA deposit in one of them and membranoproliferative glumerolonephritis in another one. Two remaining patients had serum creatinine > 2 mg/dL without any hematuria or proteinuria. Serologic study for viral agents and collagen vascular disease were negative in all patients with renal involvements. In conclusion, renal involvement in BD is not infrequent, although in most cases it is mild in nature and may be missed. (author)

THE NEPHROTOXICITY RISK IN RATS SUBJECTED TO HEAVY MUSCLE ACTIVITY

Directory of Open Access Journals (Sweden)

Gülsen Öner

2009-09-01

Full Text Available When the body is exposed to insults, the kidneys exhibit adaptive changes termed renal cytoresistance, characterized by cholesterol accumulation in the membranes of the tubule cells. However, heavy muscle activity has not yet been accepted as one of the stressors that could lead to cytoresistance. In order to study the renal functional characteristics of animals exposed to heavy muscle activity, rats were subjected to exhaustive treadmill exercise for 5 days and their data was compared to those of sedentary controls. It was found that in exercised rats, blood lactate, muscle citrate synthase and proximal tubule peroxynitrite levels were all elevated, suggesting the presence of oxidative stress in the proximal tubule segments. However, mean arterial pressure, renal blood flow, glomerular filtration rate, fractional excretion of sodium and potassium, and organic anion excretion remained normal. Despite unchanged blood cholesterol levels, cholesterol loading in the proximal tubule segments, especially the free form, and decreased lactate dehydrogenase release from cytoresistant proximal tubule segments indicated the development of renal cytoresistance. However, this resistance did not seem to have protected the kidneys as expected because organic anion accumulation associated with glycosuria and proteinuria, in addition to the elevated urinary cholesterol levels, all imply the presence of an impaired glomerular permeability and reabsorption in the proximal tubule cells. Therefore, we suggest that in response to heavy muscle activity the tubular secretion may remain intact, although cytoresistance in the proximal tubule cells may affect the tubular reabsorptive functions and basolateral uptake of substances. Thus, this differential sensitivity in the cytoresistance should be taken into account during functional evaluation of the kidneys

Diagnosis of renal disease in rabbits.

Science.gov (United States)

Harcourt-Brown, Frances Margaret

2013-01-01

There are differences in renal anatomy and physiology between rabbits and other domestic species. Neurogenic renal ischemia occurs readily. Reversible prerenal azotemia may be seen in conjunction with gut stasis. Potentially fatal acute renal failure may be due to structural kidney damage or post-renal disease. Chronic renal failure is often associated with encephalitozoonosis. Affected rabbits cannot vomit and often eat well. Weight loss, lethargy, and cachexia are common clinical signs. Polydypsia/polyuria may be present. Derangements in calcium and phosphorus metabolism are features of renal disease. Radiography is always indicated. Urolithiasis, osteosclerosis, aortic and renal calcification are easily seen on radiographs. Copyright © 2013 Elsevier Inc. All rights reserved.

Renal denervation in a patient with Alport syndrome and rejected renal allograft

Directory of Open Access Journals (Sweden)

Narayana Raju

2015-12-01

Full Text Available Renal denervation is a new intervention to treat resistant hypertension. By applying radiofrequency (RF to renal arteries, sympathetic nerves in adventitia layer of vascular wall can be denervated. Sympathetic hyperactivity is an important contributory factor in hypertension of hemodialysis patients. Hyperactive sympathetic nervous system aggravates hypertension and it can cause complications like left ventricular hypertrophy, heart failure, arrhythmias and atherogenesis. Our report illustrates the use of renal denervation using conventional RF catheter for uncontrolled hypertension in a patient with Alport syndrome and rejected renal allograft. Progressive and sustained reduction of blood pressure was obtained post-procedure and at 24 months follow-up with antihypertensives decreased from 6 to 2 per day, thereby demonstrating the safety, feasibility, and efficacy of the procedure. There are some reports available on the usefulness of this technique in hemodialysis patients; however, there are no studies of renal denervation in patients with Alport syndrome and failed allograft situation.

Renal denervation in a patient with Alport syndrome and rejected renal allograft.

Science.gov (United States)

Raju, Narayana; Lloyd, Vincent; Yalagudri, Sachin; Das, Bharati; Ravikishore, A G

2015-12-01

Renal denervation is a new intervention to treat resistant hypertension. By applying radiofrequency (RF) to renal arteries, sympathetic nerves in adventitia layer of vascular wall can be denervated. Sympathetic hyperactivity is an important contributory factor in hypertension of hemodialysis patients. Hyperactive sympathetic nervous system aggravates hypertension and it can cause complications like left ventricular hypertrophy, heart failure, arrhythmias and atherogenesis. Our report illustrates the use of renal denervation using conventional RF catheter for uncontrolled hypertension in a patient with Alport syndrome and rejected renal allograft. Progressive and sustained reduction of blood pressure was obtained post-procedure and at 24 months follow-up with antihypertensives decreased from 6 to 2 per day, thereby demonstrating the safety, feasibility, and efficacy of the procedure. There are some reports available on the usefulness of this technique in hemodialysis patients; however, there are no studies of renal denervation in patients with Alport syndrome and failed allograft situation. Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Radionuclide renal dynamic and function study

International Nuclear Information System (INIS)

Guan Liang

1991-01-01

The radionuclide dynamic and function study, glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were reported in 14 cases of renal and ureteral calculi patients before and after extracorporeal shock wave lithotripsy (ESWL). In 12 cases with normal renal blood flow, within 3 months after ESWL, the GFR of shock and non-shock side decreased with different extent, while the individual ERPF had little change. In 5 cases followed up 1 year after ESWL, the individual GFR and ERPF were normal. In 2 cases of severe renal function insufficiency, there was no improvement in renal function in shock side, after 5 months and 1 year, the renal function was still at low level. Thereby it is considered that ESWL is not suitable for the renal calculi patients with severe renal function insufficiency

Superselective renal artery embolization with lipiodol and absolute alcohol emulsion for renal tumor

International Nuclear Information System (INIS)

Yu Miao; Li Jiakai; Sun Minglu; Wang Huixian

2008-01-01

Objective: To evaluate the efficacy of the renal arterial embolization with lipidol and absolute alcohol emulsion in the treatment of renal tumors. Methods: The superselective renal arterial embolization by using coaxial-cathaterization with infusion of lipiodol and absolute alcohol (in proportion of 2 :1) emulsion was performed in twenty patients with malignant and benign kidney tumors. 4 weeks later, the renal arteriography was taken routinely and repeated embolization was performed in case of necessary; and follow up was carried out periodically. Results: The imaging findings showed thorough tumor necrosis and feeding vessel abruption in 18 cases after one session of treatment. The volume of tumors decreased more than a half in 13 patients (82.25%, 13/18) associated with a well-distributed lipidol inside the tumors. The second session of treatment was performed in other 2 patients and the clinical symptoms relieved obviously. Conclusions: The superselective renal artery embolization with lipidol and absolute alcohol emulsion can permanently embolize all tumor feeding arteries in capillary vessel level with maximum reservation of renal function, providing definitively efficacy and worthwhile to be recommended widely. (authors)

Bilateral papillary renal cell carcinoma

International Nuclear Information System (INIS)

Gossios, K.; Vazakas, P.; Argyropoulou, M.; Stefanaki, S.; Stavropoulos, N.E.

2001-01-01

Papillary renal cell carcinoma is a subgroup of malignant renal epithelial neoplasms. We report the clinical and imaging findings of a case with multifocal and bilateral renal cell carcinoma which are nonspecific. (orig.)

Nuclear localization and transactivating capacities of the papillary renal cell carcinoma-associated TFE3 and PRCC (fusion) proteins

NARCIS (Netherlands)

Weterman, M. A. J.; van Groningen, J. J.; Jansen, A.; van Kessel, A. G.

2000-01-01

The papillary renal cell carcinoma-associated t(X;1)(p11;q21) leads to fusion of the transcription factor TFE3 gene on the X-chromosome to a novel gene, PRCC, on chromosome 1. As a result, two putative fusion proteins are formed: PRCCTFE3, which contains all known domains for DNA binding,

Blunt renal trauma in children: healing of renal injuries and recommendations for imaging follow-up

International Nuclear Information System (INIS)

Abdalati, H.; Bulas, D.I.; Sivit, C.J.; Majd, M.; Rushton, H.G.; Eichelberger, M.R.

1994-01-01

Initial CT grading of renal injury was correlated with the frequency of complications and the time course of healing in 35 children. All renal contusions (grade 1, 8) and small parenchymal lacerations (grade 2, 8) healed without complications. All lacerations extending to the collecting system (grade 3, 9) resulted in mild to severe loss of renal function with progressive healing over 4 months. One of four segmental infarcts (grade 4 A), and five of six vascular pedicle injuries (grade 4 B) resulted in severe loss of renal function. Complications, including urinoma (2), sepsis (1), hydronephrosis (1), and persistent hypertension (2), were limited to grade 3 and 4 injuries. Our results suggest that mild renal injuries do not require follow-up imaging. Major renal lacerations and vascular pedicle injuries, however, often result in loss of renal function and should be followed up closely due to the risk of delayed complications. Follow-up examinations should continue for 3-4 months until healing is documented. (orig.)

Renal contrast-enhanced MR angiography: timing errors and accurate depiction of renal artery origins.

Science.gov (United States)

Schmidt, Maria A; Morgan, Robert

2008-10-01

To investigate bolus timing artifacts that impair depiction of renal arteries at contrast material-enhanced magnetic resonance (MR) angiography and to determine the effect of contrast agent infusion rates on artifact generation. Renal contrast-enhanced MR angiography was simulated for a variety of infusion schemes, assuming both correct and incorrect timing between data acquisition and contrast agent injection. In addition, the ethics committee approved the retrospective evaluation of clinical breath-hold renal contrast-enhanced MR angiographic studies obtained with automated detection of contrast agent arrival. Twenty-two studies were evaluated for their ability to depict the origin of renal arteries in patent vessels and for any signs of timing errors. Simulations showed that a completely artifactual stenosis or an artifactual overestimation of an existing stenosis at the renal artery origin can be caused by timing errors of the order of 5 seconds in examinations performed with contrast agent infusion rates compatible with or higher than those of hand injections. Lower infusion rates make the studies more likely to accurately depict the origin of the renal arteries. In approximately one-third of all clinical examinations, different contrast agent uptake rates were detected on the left and right sides of the body, and thus allowed us to confirm that it is often impossible to optimize depiction of both renal arteries. In three renal arteries, a signal void was found at the origin in a patent vessel, and delayed contrast agent arrival was confirmed. Computer simulations and clinical examinations showed that timing errors impair the accurate depiction of renal artery origins. (c) RSNA, 2008.

Renal embolic protection devices improve blood flow after stenting for atherosclerotic renal artery stenosis.

Science.gov (United States)

Paul, Timir K; Lee, John H; White, Christopher J

2012-11-15

We sought to measure angiographic renal frame counts (RFC), as a quantitative angiographic assessment of renal blood flow, to evaluate microvascular compromise due to atheroembolism associated with RAS. Atheroembolism associated with renal artery stenting (RAS) has been implicated as a cause for worsening renal function following successful intervention. Use of a distal embolic protection device (EPD) during RAS has been shown to be safe with debris capture in a high percentage of cases. However, objective benefit for renal function with EPD has been difficult to demonstrate. A control group of 30 consecutive patients (33 kidneys) who underwent RAS without EPD were compared with 33 consecutive patients (33 kidneys) who underwent RAS with EPD using RFC measurement. The prestent and poststent mean RFC for the control group was 30.4 ± 12.1 vs. 23.7 ± 9.9 (P = 0.002) and for the EPD group it was 42.6 ± 12.6 vs. 28.3 ± 9.2 (P renal blood flow, manifested by a greater reduction of the RFC (Δ RFC) 14.2 ± 15.2 vs. 6.7 ± 11.7 (P = 0.03) compared with the control group. The use of an EPD was associated with a much larger improvement in renal blood flow (lower RFC) following RAS. This suggests that EPD's may be effective in preventing renal atheroembolic injury and that a controlled trial measuring the impact of EPD's on renal blood flow following RAS should be performed. Copyright © 2012 Wiley Periodicals, Inc.

Hypogonadism and renal failure: An update.

Science.gov (United States)

Thirumavalavan, Nannan; Wilken, Nathan A; Ramasamy, Ranjith

2015-01-01

The prevalence of both hypogonadism and renal failure is increasing. Hypogonadism in men with renal failure carries with it significant morbidity, including anemia and premature cardiovascular disease. It remains unclear whether testosterone therapy can affect the morbidity and mortality associated with renal failure. As such, in this review, we sought to evaluate the current literature addressing hypogonadism and testosterone replacement, specifically in men with renal failure. The articles chosen for this review were selected by performing a broad search using Pubmed, Embase and Scopus including the terms hypogonadism and renal failure from 1990 to the present. This review is based on both primary sources as well as review articles. Hypogonadism in renal failure has a multifactorial etiology, including co-morbid conditions such as diabetes, hypertension, old age and obesity. Renal failure can lead to decreased luteinizing hormone production and decreased prolactin clearance that could impair testosterone production. Given the increasing prevalence of hypogonadism and the potential morbidity associated with hypogonadism in men with renal failure, careful evaluation of serum testosterone would be valuable. Testosterone replacement therapy should be considered in men with symptomatic hypogonadism and renal failure, and may ameliorate some of the morbidity associated with renal failure. Patients with all stages of renal disease are at an increased risk of hypogonadism that could be associated with significant morbidity. Testosterone replacement therapy may reduce some of the morbidity of renal failure, although it carries risk.

The valuation of 99Tcm-DMSA renal cortical scintigraphy for prediction of renal scarring in children with acute pyelonephritis

International Nuclear Information System (INIS)

Zhao Ruifang; Ji Zhiying; Lv Xiaomei; Wu Ha; Li Yiwei; Gu Fanlei; Zhao Xiaofei

2009-01-01

Objective: Acute pyelonephritis (APN) is a common infectious disease in childhood. APN may result in ineversible renal scarring. 99 Tc m -dimercaptsuccinic (DMSA) renal cortical scintigraphy was reported to be highly sensitive and specific for detection APN and renal scarring. The aim of this study was to determine the incidence of renal scarring in a group of children with APN and to evaluate the relative factors at risk of scarring using 99 Tc m -DMSA renal cortical scintigraphy. Methods: One hundred and eighteen patients (44 males, 74 females, age range: 1 month to 14 years) with APN underwent DMSA renal cortical scan before treatment and six month after treatment to identify renal damage and renal scarring. The degree of renal damage was divided to grade I to IV. A directed radionuclide cystography (DRC) was performed in 72 cases to evaluate vesicoureteric reflux (VUR). Statistical analysis between all those relative factors was performed using Spearman grading relational analysis. The software was SPSS 11.5. Results: The follow-up renal cortical scan revealed that 79 normal kidneys on first scan remained normal; of 64 kidneys with grade I damage, 7.81% (5/64) developed renal scar; of 51 kidneys with grade II, 49.02% (25/51) developed renal scar; of 19 with grade III, 68.42% (13/19) developed renal scar; of 23 with grade IV, 100.00% (23/23) developed renal scar. There was a significant relationship between the incidence of renal scar on follow-up and the grade of renal damage on first scan (r=0.877, P<0.01). VUR was found in 54.17% (78/144) per renal unit. Only 4.55% (3/66) of those with non-refluxing ureters developed renal scars on follow-up. One of four patients with mild-refluxing ureters developed renal scars. 46.51% (20/43) of those with moderate-refluxing ureters developed renal scars. 87.10% (27/31) of those with severe-refluxing ureters developed renal scars. There was a significant relationship between the incidence of renal scarring in follow-up and

Relationship between renal hemodynamic status and aging in patients without diabetes evaluated by renal Doppler ultrasonography.

Science.gov (United States)

Kawai, Tatsuo; Kamide, Kei; Onishi, Miyuki; Hongyo, Kazuhiro; Yamamoto-Hanasaki, Hiroko; Oguro, Ryosuke; Maekawa, Yoshihiro; Yamamoto, Koichi; Takeya, Yasushi; Sugimoto, Ken; Ohishi, Mitsuru; Rakugi, Hiromi

2012-10-01

Aging is well known as one of the major causes of a reduced glomerular filtration rate (GFR). The resistive index (RI) measured by renal Doppler ultrasonography (RDU) is thought to be a good indicator of renal vascular resistance induced by arteriosclerosis. In this study, we investigated whether RI could be used to evaluate the pathogenesis of renal damage or the mechanisms of reduction of renal function by aging. We investigated the correlation between RI and multiple clinical parameters and the influence of aging on the renal hemodynamic status of 194 in-patients (mean age 66.2 years) who underwent RDU at our hospital between February 2009 and July 2010. RI was significantly correlated with the age, estimated GFR (eGFR), diastolic blood pressure, pulse pressure, and degree of albuminuria. Subjects aged ≥75 years showed a significantly higher correlation coefficient between eGFR and RI. RI showed a stronger correlation with age in subjects aged ≥75 years compared to eGFR. The present study showed that renal vascular resistance and intra-renal arteriosclerosis had a greater impact on renal function in older than younger subjects, reflecting the possible mechanisms of renal function reduction due to aging.